Student / Faculty Presentations

28TH PUERTO RICO NEUROSCIENCE CONFERENCE

Poster Presentation

Presenter: Gabriel Rojas-Bowe
Institution: University of Puerto Rico School of Medicine
Title: Prelimbic neurons signal approach-avoidance conflict
Authors: Gabriel Rojas-Bowe, Albit Caban-Murillo, Hector Bravo-Rivera, Shantee Ayala-Rosario, Jose Pérez-Torres, Viviana Valentín-Valentín, Arturo Rivera-Rivera, Christian Bravo-Rivera, P.I. Gregory J. Quirk

Abstract: In nature, animals must carefully evaluate when to approach rewards or avoid threats in risky environments. The neural mechanisms that underlie the resolution of approach/avoidance conflict remain unknown. We recently developed an approach/avoidance conflict task (Bravo-Rivera et al., in review) that pits food reward approach against threat (foot-shock) avoidance. In brief, male rats learn to avoid a tone-signaled foot-shock by stepping onto a platform and to seek a light-signaled reward by pressing a lever (located far from the platform). When the tone and light cues are co-presented, rats initially engage in lever pressing and then move onto the platform at the late phase of the trial to timely avoid the foot-shock. Pharmacological inactivation of the prelimbic (PL) cortex accelerated cue-induced avoidance, suggesting that PL delays avoidance to accommodate food-seeking under conflict conditions (t(18) = 2.71, p = 0.014). Single-unit recordings revealed that populations of PL neurons distinguished the combined tone and light (conflict trials) stimulus from the tone-alone and light-alone (non-conflict) stimuli: 26.5% of all responsive cells (n = 207) responded exclusively to conflict trials, whereas 21.4% exclusively responded to the tone-alone trials and 15% responded to the light-alone trials exclusively. Moreover, a subset of PL neurons signaled lever presses during the conflict trials, but not during the light-alone trials, whereas another subset displayed opposite responses. Whereas 28.8% of all responsive cells (n = 208) responded exclusively to pressing within the conflict trials, 38.0% exclusively responded to pressing within the light-alone trials. Furthermore, whereas a subset of PL neurons (47.4% of 78 responsive cells) signaled platform mounts occurring exclusively under conflict trials, another subset (37.2%) exclusively responded to mounting under the tone-alone trials. These findings suggest that PL signals conflict-relevant stimuli and the appropriate behavioral response.

Presenter: Osmarie Martínez
Institution: University of Puerto Rico-Medical Science Campus
Title: Effects of closed-head injury on fear and anxiety-like behaviors in rats
Authors: Osmarie Martínez-Guzmán, Melissa Rivera-López, Mauricio Cáceres-Chacón, Hector Haddock-Martínez, PI: Demetrio Sierra-Mercado

Abstract: Concussion, the most common form of brain injury, is frequently seen in contact sports and military combat. Although human studies show a correlation between suffering a concussion and enhanced fear, animal studies show conflicting results. For example, rodent studies suggest that brain injury may enhance (Reger et al., 2012) or reduce fear expression, (Palmer et a., 2016), or have no effect (Sierra-Mercado et al., 2015). Something that may contribute to these conflicting results in animal studies is the timing of injury when examining fear-related behaviors. Most animal studies assess the effects of injury on fear behaviors by giving the injury prior to fear learning (Davies et al., 2016). However, less is known about the effects of injury on fear memory, which would require giving the injury after fear learning. We hypothesize that concussive-like injury after fear learning will decrease fear memory in rats. To test this hypothesis, we mimicked concussion in rats using closed head injury (CHI) and examined fear behaviors using Pavlovian fear conditioning. During conditioning (fear learning) a tone was paired with a foot shock. This was followed by CHI or sham injury. After a month, fear memory was tested by exposing the animals to the tone without the shock, and freezing behavior was measured as an index of fear. Results showed no significant difference in percent freezing during memory test (Sham: 79%, n=8; CHI: 77%, n=9). This suggests that CHI does not affect the consolidation or expression of fear memory. Future studies will focus on examining brain tissue for changes in neuronal activity and also neuroinflammation to determine how CHI contributes to the neurobiology of learned fear.

Presenter: Claudia Ramos
Institution: University of Puerto Rico- Rio Piedras Campus
Title: Gene ontology analysis of long-term alcohol-induced neuroadaptation.
Authors: Claudia Ramos, Corinne Croslyn, Dr. Alfredo Ghezzi

Abstract: In this study we were aiming to uncover the networks of genes that are actively expressed when flies are exposed to ethanol vapor. Clustering them by gene ontology which further subdivides them in three sub-categories. It is divided into three GO types: biological process, molecular function, and cellular component. Gene Ontology (GO) is a system of classification in which genes are sorted by their functional characteristics. It serves to essentially acquire biological meaning from our random set of fruit fly RNA-sequences. GO works by performing an enrichment analysis on particular gene sets, it will determine which genes are being overrepresented or underrepresented within that gene set. We used DAVID, a web-accessible program, to group the genes based on their biological function. Known categories such as sex differentiation were confirmed but new categories of genes were discovered which can be studied soon.

Presenter: Alexdiel Figueroa
Institution: University of Puerto Rico Río Piedras
Title: The Effect of Glyphosate on Recognition Memory in Rats.
Authors: Mauricio Cáceres-Chacón Héctor Haddock-Martínez Osmarie Martínez-Guzmán Melissa Rivera-López PI: Demetrio Sierra-Mercado

Abstract: Glyphosate was initially considered safe because it acts by inhibiting a metabolic route that is not present in mammals. However, case studies have highlighted its neurotoxic effect on memory. Moreover, studies have shown that rats exposed to glyphosate display decreased working memory. Few studies have evaluated the effect of glyphosate on recognition memory. Therefore, we aimed to evaluate the effect of intraperitoneal glyphosate on recognition memory. To test this, rats were intraperitoneally injected every two days with 100mg/kg of glyphosate for two weeks. We then tested the rats in a novel object recognition task. This task consists of two phases, the first is a familiarization phase where the animals are presented with two identical objects and allowed to explore them. The second phase consists of reexposing the animals to the objects with one being replaced with a new object. During the familiarization phase, both glyphosate and control animals spent similar amount of time exploring both objects, expressed as percent time with object 1 (control: 61% n=5, glyphosate: 60% n=6; p=0.913). One hour later, animals were tested for recognition memory. Here, animals treated with glyphosate were not able to discern the novel object and spent a similar amount of time exploring both objects, expressed as a percent time with the novel object (control: 0.71 n=5, glyphosate: 0.47 n=6; p=0.059). Moreover, glyphosate decreased the calculated recognition index (novel-familiar/novel+familiar) (control: 0.487 n=5, glyphosate: -0.062 n=6; p=0.059). In conclusion, intraperitoneal glyphosate may affect recognition memory, however, studies with a larger sample size are required. Future directions include increasing our sample size and performing immunohistochemistry on brain regions important for memory.

Presenter: Kiara M Cardona Jordán
Institution: UPR-School of Medicine
Title: Effects of BPA exposure on Anxiety Behaviors Necessary for Survival.
Author: Eliezer Cartagena, Katherine Cordero, Cristina Velázquez, Ph.D.

Abstract: Bisphenol- A (BPA) is an anthropogenic stressor mass produced to assist in the manufacturing of almost all plastics and resins since the 1960s. Plastic pollution has become an increasing concern over the past six decades with BPA production surpassing 7 billion kilograms per year. It is common to encounter BPA in air, dust, food and water. Heat and changes in pH cause this chemical to leach out of products and spread throughout the environment. Important environmental organizations like EPA, has declared BPA as the third highest priority environmental hazard. The concentrations of BPA in the environment varies depending on location, its temperature, pH, source and time of sampling. For example, BPA has been detected in the effluents in the United States at concentrations of 12 µg/L.

The current U.S. EPA (Environmental Protection Agency) reference for Lowest Observed Adverse Effect Level (LOAEL) is 50 mg/kg/d, of BPA5. Previous studies have shown that at low BPA concentrations, i.e. 2 mg/kg/day, there are some effects on the development of secondary sexual characteristics and neurotoxic effects in brain and behavior. Specifically, neurologic effects have been noted after early life exposure to BPA in the rodent brain, producing deficits in social behavior, cognitive impairment and increases in anxiety and depression-like behavior. All of these deficits compromise the innate ability to face challenges and limits chances for survival. Furthermore, current research has determined a link between BPA-induced epigenetic changes in early childhood, leading to altered expression and DNA methylation of Fkbp5 gene, associated to increasing sensitivity to stress and the risk of developing PTSD and anxiety behaviors.Despite these potential indicators, there has been no research directly addressing the development of anxiety-like behavior in response to BPA exposure in early stages of development. Preliminary data with adult male mice, had showed that expression of fear is significantly less in Bisphenol-A exposed mice (50ppm) than control group during conditioned learning. Therefore, our hypothesis states that early exposure to BPA increases the likelihood of developing stress response correlated to anxiety-like disorders. I propose to study the effects of physiologically relevant concentrations of BPA on adolescent mice and using the open field test in order to continue establishing a relationship of this anthropogenic stressor with anxiety-like behaviors.

Presenter: Katherine Cordero Padilla
Institution: University of Puerto Rico - MSC
Title: Lead-induced hippocampal changes in BDNF gene expression and neuronal survival.
Author: Katherine Cordero Padilla PI: Dr. Cristina Velazquez

Abstract: Lead, a non-biodegradable metal, is one of the most ubiquitous persistent toxicants present in the environment. It spread in the environment by the many industrial uses the metal has, for example: manufacturing of pipes, lead-based paints, ceramic glazes, batteries, pottery, and ammunition. Developmental exposure to lead (Pb) causes deficits in cognitive functions, IQ, behavioral effects, and attention deficit hyperactivity disorder (ADHD). Despite growing research interest, the molecular mechanisms responsible for the effects of lead in the central nervous system are still largely unknown. For decades, Puerto Rico’s tap water has often gone untested, raising fears about lead contamination. A publication by NPR (National Public Radio) and EPA (Environmental Protection Agency) revealed the crisis that Puerto Rico has regarding water maintenance and according to data reported by the island's water systems between January 2015 and March 2018; “97 percent of Puerto Rico's population is served by a local drinking water system with at least one recent violation of the Safe Drinking Water Act's lead and copper testing requirements. As contamination of our water supply increases so have the incidences of deficits in cognitive functions, behavioral effects, and ADHD in our overall population increasing the urgency of further understanding the possible links between contaminants and neuronal changes in gene expression underlying many of these pathologies.

Previous studies showed that the hippocampus was the area where gene expression changes due to Pb exposure were most pronounced during childhood. Studies using primary neuronal cultures with lead exposure during childhood showed that it may negatively modify important neuronal pathways in the hippocampus, cortex, and thalamus implicated in synaptic plasticity, cell survival and expression and translocation of brain-derived neurotrophic factor (BDNF). BDNF is a protein known for promoting the development and survival of nerve cells within the hippocampus by playing a role in the growth, differentiation and maintenance of these cells. Although much of the information points towards possible transcriptional dysregulation of BDNF in the hippocampus [1] and separately BDNF’s role in neuronal survival, there have been no studies addressing directly the possibility of lead induced, BDNF abnormal transcriptional regulation within the hippocampus leading to deficiencies in neuronal survival. Therefore, we hypothesize that changes in BDNF gene expression are key in determining known changes in neuronal survival due to physiologically relevant concentrations of Pd exposure.

Presenter: Sian Rodríguez
Institution: University of Puerto Rico at  Río Piedras
Title: The Utility of SPECT-CT and PET-CT in the diagnosis of Traumatic Brain Injury at the VA Caribbean Healthcare System (VACHS): Retrospective Descriptive Study.
Authors: Marleni Pagán-Ramos Gerardo Jovet, MS Clara Dismuke, MD Ivette M. Freytes, MD Keryl Motta, MD PI: Irma L. Molina-Vicenty, MD

Abstract: Traumatic Brain Injury (TBI) is a neurological impairment where the patient suffers damage to the brain by mechanical forces such as an impact to an object and the waves of a blast, among others. The effects of the impairment happen over time, with subjects showing behavioural and anatomical deficits. This is of importance for Veterans Affairs since approximately 20% of Iraq veterans have suffered TBI. Because of this, the study’s purpose is to characterize brain injuries among Operation Enduring Freedom (OEF), Operation Iraqi Freedom (OIF) and Operation New Dawn (OND) VACHS Veterans using Nuclear Medicine neuron-imaging and to create a sociodemographic and health characteristic profile. We want to make a description of TBI lesions in veteran patients with TBI using Single photon emission computed tomography (SPECT-CT) and Positron emission tomography (PET-CT). We also want to evaluate the physical, cognitive, and psychological symptomatology with patients with TBI and the association between magnitude of brain injury and said symptomatology. We will make approximations of association between the neuro-imaging parameters and cognitive and motor assessment scores. And finally, we want to make a socio demographic and health characteristics profile of the VACHS TBI patients. We predict that Nuclear Medicine neuroimaging will classify veterans returning from OEF/OIF/OND into different brain impairment groups depending on the anatomical region. We also predict that these different impairment groups will correlate with different physical, cognitive and/or psychological symptomatology. We worked with medical records of males and females that returned from OEF, OIF or OND between the ages of 21 and 89 that were diagnosed with TBI by the VACHS who had a PET-CT and/or SPECT-CT between January 2007 and September 2015. Preliminary results on the first 100 subjects show that most of the study population were male between 23 and 62 years old, the majority were married, white, Hispanic and had some college experience. Neuroimaging results show that 96 had SPECT/CT, 4 had PET/CT, and 3 had both neuro-images. Most common location for TBI lesions using SPECT/CT and PET CT was the frontal lobe. We found that most patients suffered from mild TBI which was caused by a blast/explosion. Symptomatology results showed that irritability, forgetfulness, and headaches were the most common psychological, cognitive, and physical defects, respectively. Data on service utilization presented that 31% had a hospital admission with an average of 15 bed days of care, 88% went to Occupational Therapy, 85% to Physical Therapy and 46% to Speech Therapy. The average outpatient visits were 53 per year. These patterns of data back up the expected results from what we predicted. The groups were divided into five major brain impairment groups and we were able to make inverse correlations between TBI severity and cognistat score. We also saw a positive correlation between depression and number of comorbidities.

Presenter: Lindsey Williams
Institution: Veterans Affairs Puget Sound Health Care System
Title: Evaluation of Blood-to-Brain Glucose Transport Kinetics and GLUT-1 Regulation in a Human iPSC-derived In Vitro Blood-Brain Barrier System.
Authors: Lindsey M. Williams PI: Michelle A. Erickson William A. Bank

Abstract: The blood-brain barrier (BBB) is an important brain interface that regulates the transport of molecules into and out of the brain. The primary units comprising the BBB are brain endothelial cells (BECs). Human stem cell-derived in vitro models of brain endothelial cells (iBECs) have attracted much attention in recent years, in part, because they overcome some disadvantages of primary and immortalized human BECs such as limited availability and difficulty maintaining strong barrier properties. iBECs can achieve strong barrier properties representative of in vivo barrier function, and thus offer a robust platform for studying BBB transporters with minimal confounds from leakage. GLUT-1 is a vital BBB transporter that facilitates the bidirectional diffusion of glucose between the blood and brain compartments. GLUT-1 deficiency is detrimental for normal brain functions, and GLUT-1 dysfunction has been implicated in neurodegenerative conditions such as Alzheimer’s disease. We have developed a robust assay to examine the kinetics and regulation of glucose transport across brain endothelial-like cell monolayers derived from human iPSCs. Our main findings show that GLUT-1 transporter function decreases over time as iBECs are maintained in culture, while GLUT-1 protein expression increases and barrier properties strengthen. We further show that inhibition of Notch signaling, which increases GLUT-1 transporter function in BECs, decreases GLUT-1 transport in iBECs. Our findings support that iBECs are a highly scalable and translatable model that affords the opportunity to investigate the physiological regulation of GLUT-1, as well as its dysfunction in pathological contexts.

Presenter: Amanda Anqueira
Institution: University of Puerto Rico at Rio Piedras
Title: The Molecular Mechanisms of Ethanol Neuroadaptations
Authors: Nicolás Fuenzalida José Agosto PI: Alfredo Ghezzi

Abstract: The Molecular Mechanisms of Cognitive Ethanol Neuroadaptations Alcohol consumption is known to induce cognitive impairments mainly affecting executive functions, episodic memory, and other capacities related to brain function. Nevertheless, the cellular and molecular mechanisms underlying such interactions is still unknown. Recent evidence has uncovered a similar interaction between ethanol exposure and cognitive function in the fruit fly, Drosophila melanogaster, which opens the way for molecular studies in a genetically tractable model system. Using an olfactory conditioning assays where an odorant is used as a conditioned stimulus (CS) and is paired with a heat shock used as an unconditioned stimulus (US), it was shown that Drosophila larvae can learn to avoid the odor in future exposures. However, when the animals are exposed to a short acute dose of alcohol, they are no longer able to learn this association. Interestingly, larvae that have undergone prolonged chronic ethanol exposure seem to successfully avoid the odorant paired with the heat shock just as well as control ethanol-naive larvae, which is suggestive of ethanol-induced neuroadaptations. Our aim is to understand the genetic and cellular components responsible for this adaptation. For this, we employ RNA Sequencing technology to evaluate differences in gene expression in the brain of larvae chronically exposed to ethanol and in control larvae. Results from RNA sequencing suggest neuroadaptations are modulated by a diverse array of synaptic proteins within the larvae brain. With the knowledge obtained from this study, we could be able to understand ethanol’s effect on learning and memory and gain an insight into how addiction may be contributing to damages in this behavior.

Presenter: Mauricio Caceres-Chacón
Institution: University of Puerto Rico School of Medicine
Title: Effects of glyphosate on anxiety-like behaviors and fear in rats
Authors: Héctor Haddock-Martínez Osmarie Martínez-Guzmán, PhD Melissa Rivera-López
PI: Demetrio Sierra-Mercado, PhD

Abstract: Glyphosate, the active ingredient in several commercial herbicides, was initially considered safe for humans since it exerts its effect by inhibiting a metabolic route not present in mammals. However, case studies highlight glyphosate’s potential neurotoxicity in patients exposed to high doses of glyphosate (Menkes, et. al. 1991, Sato, et. al. 2011). Moreover, epidemiological studies have shown that the increased use of glyphosate-based herbicides strongly correlates with the development of neurological and emotional disorders (Seneff et al., 2015). Rodent studies have demonstrated that glyphosate exposure can lead to increased expression of anxiety-like behaviors, and cellular changes in brain regions important for anxiety such as the prefrontal cortex and basolateral amygdala (Baier et al., 2017, Ait Bali et al., 2017). However, despite the similarity between the brain circuitry of anxiety and that of fear, the effect of glyphosate on the expression of fear has not been studied. To assess this, rats were intraperitoneally injected every two days with either 100mg/kg of glyphosate (Gly) or saline for controls, for three weeks. After two weeks of exposure, rats were evaluated for anxiety-like behaviors in the open field test (OFT) and the light/dark box, and for fear expression using Pavlovian fear conditioning. In the OFT, glyphosate reduced time spent in the center (Gly: 65.45, Controls: 126.5; n=4; p=0.0268) and number of entries to the center (Gly: 19.75, Controls: 37.0; n=4, p=0.0329), suggesting increased anxiety-like behaviors. Moreover, when animals were evaluated in the light/dark box, glyphosate decreased the time required to exit the light (Gly: 0.75, Controls: 5.175; n=4; p=0.0439) and showed a tendency to decrease the time spent in the light (Gly: 10.88, Controls: 41.18; n=4; p=0.0579). During conditioning (fear learning) a tone was paired with a foot shock in an operant chamber. To test for fear memory, the animals were exposed to the tone without a shock, and the percent of time freezing was measured as an index of fear. Glyphosate did not affect neither fear learning as noted by identical levels of freezing at the end of conditioning (avg. of last two trials; Gly: 60.5%, Controls: 59.2%; n=4, p=0.8), nor fear memory (avg. of first two trials; Gly: 92.0%, Controls: 86.5%; n=4, p=0.1). Overall, it does not appear that glyphosate affects the expression of fear. Our future directions include increasing our sample size, assessing neuronal activity in the prefrontal cortex and basolateral amygdala, and considering a method of exposure that is less stressful than repeat intraperitoneal injections.

Presenter: Melissa Rivera-López
Institution: University of Puerto Rico, Medical Sciences Campus
Title: The Effects of Atrazine on Fear Behaviors in Rodents.
Authors:Gabriela N. Hernández-Busot, Osmaries Martínez-Guzmán Mauricio Cáceres-Chacón Héctor Haddock-Martínez PI: Demetrio Sierra-Mercado

Abstract: Atrazine (ATR) is a widely used herbicide in agriculture. Unfortunately, excessive use of ATR has led to the contamination of food and drinking sources (Mosquin et al., 2012; Whitmore and Chen, 2013). Subsequently, this has led to humans becoming exposed to ATR in their daily life. Animal studies have shown that ATR can influence emotionally relevant behaviors such as anxiety in rodents (Ma et al., 2018; Chavez-Pichardo et al., 2020). However, other emotional behaviors such as fear remain unexplored. To address this gap, rats were exposed to ATR in their drinking water at a dose considered safe for ingestion (0.035mg/kg; Environmental Protection Agency), whereas control animals received filtered water. Both groups had ad libitum access to water for four months. Following exposure, fear was assessed using Pavlovian fear conditioning where rats learn that a tone predicts a shock by exhibiting freezing behavior to the tone. Anxiety-like behavior was also examined using the open field test. During fear conditioning no differences were observed in freezing behavior between groups (ATR: 66%, Controls: 68%; n=6; p=0.8577). In the open field test, ATR rats spent more time in the center compared to controls (ATR: 29.4 s, Controls: 17.6 s; n=6, p=0.0198). These results suggest that ATR does not affect fear behaviors, but it can decrease anxiety-like behaviors. Future directions include increasing our sample size and examining brain regions key to emotional behaviors, such as the amygdala, using immunohistochemistry. Our findings may help elucidate how prolonged ingestion of atrazine at a dose considered safe for humans may influence emotionally relevant behaviors.

Presenter: Gabriela Hernández-Busot
Institution: University of Puerto Rico, Medical Sciences Campus
Title: The Effect of Atrazine on Locomotion in Rats.
Authors: Melissa Rivera-López Osmarie Martínez-Guzmán Mauricio Cáceres-Chacón Héctor Haddock-Martínez PI: Demetrio Sierra-Mercado

Abstract: Atrazine (ATR) is a herbicide widely used in agriculture across the globe. The excessive use of ATR has led to the contamination of food and drinking sources, and the subsequent exposure of humans. (Kale et al., 2018). Animal studies have shown that ATR given at high doses can increase or decrease locomotion in rodents (Li et al.,2018). However, the effect of ATR at the oral reference dose (0.035mg/kg) established by the Environmental Protection Agency has not been evaluated. To test this, rats were given ATR-containing drinking water or filtered water ad libitum for three months. Following exposure, locomotion was assessed using the open field test. Here we saw an increase in total distance traveled (Control: 21.67m, ATR: 33.87m; n=6; p=0.00039), and in mean speed (ATR: 0.11 m/s, Control: 0.07 m/s; n=6, p=0.00041). However, we saw no difference in maximum speed. Future directions include increasing our n, increasing the exposure time, as well as assessing brain regions important for locomotion using immunohistochemistry. These results may help elucidate if prolonged consumption of oral atrazine at doses considered safe, affects normal locomotion.

Presenter: Yamil Miranda
Institution: University of Puerto Rico
Title: Establishing Effective Parameters for Electroporation of Echinoderm Radial Nerve Cord Explants.
Authors: Yamil D. Miranda-Negrón Eduardo Quesada-Días Paola Figueroa-Delgado Christian Castro-Ruiz PI: José García-Arrarás, PhD

Abstract: Life expectancy has greatly increased in the last century and, as a result, neurodegenerative diseases have escalated, becoming one of the leading causes of death in the USA. Since most of the nervous system failings depend on the balance between degeneration and regeneration, the basic biology behind these processes is being increasingly studied. Holothuria glaberrima serves as a powerful organism to study the neuroregeneration process. This organism has extraordinary regeneration capabilities, which are still to be elucidated. Cell de-differentiation is a central process during nerve regeneration in these organisms. To study the de-differentiation process in H. glaberrima we have established an explant culture of the radial nerve cords (RNC) and studied cellular events such as cell proliferation, cell de-differentiation and apoptosis. More recently we have established an electroporation protocol in order to explore potential de-differentiation factors using RNAi loss of function techniques. RNC explant electroporation using non-membrane permeable Tetramethylrhodamine (TMRAD) dye using 2 pulses at 5 volts for 15ms at 950ms intervals demonstrated to be most effective in allowing entrance of the dye into the cell. Significant morphological RNC explant damage was not observed even when electroporated at 15 volts, suggesting this a safe delivery method for nerve explants. Double Stranded RNA (dsRNA) sequence of Myc which is a known dedifferentiation modulator was also delivered to RNC explants and endogenous RNA levels of Myc will be measured thus demosntrating if electroporation delivery of RNAi can effectively downregulate endogenous RNA Myc levels. Successful electroporation of RNC explant has never been achieve in echinoderms thus, the establishment of this RNA delivery technique would provide a major tool for ours, and others, studies of echinoderm neurobiology and in particular for the study of their regenerative properties.

Presenter: Héctor Haddock-Martínez
Institution: University of Puerto Rico, Rio Piedras Campus
Title: Reaching a general audience through an animated video that explains the connection between mental and cardiovascular health.
Authors: Ximena Leon Davin Means Madelyn Terhune Alexander Martínez Joey Barnett, PhD
PI: Kendra Oliver, PhD

Abstract: Reaching a general audience through an animated video that explains the connection between mental and cardiovascular health Mental health can influence cardiovascular health via the autonomic nervous system. Thus, proper mental health can help reduce the risk of cardiovascular disease. However, many people are not aware of this. This is especially true among minorities and socioeconomically disadvantaged groups, who tend to have low health literacy. To address this issue, we prepared an animated video targeted towards a general audience that highlights the interaction between mind and heart. To measure the impact and reach of our video, we also prepared a survey that allowed us to collect data regarding viewer demographics. Results from our survey showed that our video failed to reach a heterogonous audience based on racial distribution amongst viewers. Thus, a stronger promotional campaign is needed in order to increase the reach of our video.

Presenter: Mario Lloret
Institution: University of Puerto Rico Medical Sciences Campus
Title: Hippocampal, Amygdalar and Accumbal BDNF Expression in Morphine Extinction
Authors: Mario E. Lloret Torres Roxsana N. Ayala Pagan Freddyson J. Martinez-Rivera
PI: Jennifer L. Barreto Estrada

Abstract: Opiate addiction has quickly become a health crisis in the United States. The Council of economic advisors estimates that the opioid crisis will have a cost of 2.5 trillion dollars from 2018 to 2022. Efforts to reduce the number of opiate addicts have led to the development of new treatment options, such as medication replacement therapies (methadone, buprenorphine) and behavioral (exposure) therapies. Despite their relative success, a high number of opiate addicts’ relapse, and many die of drug-related overdoses. We used preclinical models of addiction to understand the molecular mechanisms underlying opioid-seeking behaviors. Previously, we created an mRNA profile of the Ventral Striatum/ Nucleus Accumbens (VS/NAc) of rats who had undergone morphine extinction. We found an increase in bdnf mRNA in animals who successfully extinguished morphine place preference. Although BDNF has been associated with extinction of addictive behaviors, whether this increase at the messenger level could be translated into active protein expression, remains to be determined. Here, we measured BDNF expression in the VS/NAc of animals that underwent extinction of morphine place preference by using Western blots. In accordance with our previous finding, we found an increase in BDNF protein expression in VS/NAc of animals in the extinction group. Given that BDNF expression in VS/NAc is naturally low, we questioned whether this BDNF could be axonally transported as well, from other brain regions of the reward circuit ie., hippocampus and amygdala. In the hippocampus we found a significant increase of BDNF in animals that successfully extinguished morphine place preference, while in the amygdala, we found this increase not only in animals of the extinction group, but also in animals showing extinction failure. The observed increase in BDNF expression in the VS/NAc validates our previous findings and suggests BDNF’s viability as a potential future pharmacological target for the extinction of opioids.

Presenter: Wilfred Fonseca-Ferrer
Institution: Ponce Health University
Title: Infusion of C20 Ceramides into the Ventral Hippocampus Induces Anhedonia-like Behavior without Neuroinflammation in Rats.
Authors: Lubriel Sambolin-Escobales, MS Lizmarie Tirado-Castro, MD Kimberly Santos-Aviles, MS Norman Haughey, PhD Maria Colon, BS Anixa Hernandez, BS Gladys Chompre, PhD
PI: James Porter, PhD

Abstract: The development of major depressive disorder (MDD) is characterized by symptoms such as depressed mood, insomnia, and anhedonia. The ventral hippocampus (VH) is related to the regulation of mood and emotions disturbed in depressed patients. Previous data showed that rats with depressive-like behavior consuming high-fat diet showed increased long-chain C20 ceramides in serum. However, it is unclear if C20 ceramides are sufficient to induce depressive-like behaviors. We hypothesized that infusion of these long-chain C20 ceramides into the VH of rats would induce depressive-like behaviors and develop a neuroinflammatory profile. To test this, P60 male and female rats received seven infusions of C20 ceramides directly into the VH, one infusion every 48 hours. Twenty-four hours after each infusion, a sucrose preference test was performed to assess the anhedonia-like behavior. Rats that received C20 infusions showed a reduction for sucrose preference suggesting the development of anhedonia. In  contrast, C20 infusions did not affect behavior in a sucrose grooming or a forced swim test. After sacrifice, VH tissue was extracted to perform immunofluorescence to assess cannula placement in the VH. Moreover, VH tissue was used to assess the neuroinflammatory profile performing quantitative Real-Time PCR to measure the mRNA expression of the microglia marker Iba-1 and the inflammatory markers TNF-α, NLRP3, HMGB-1, and TLR-4. The results show that the ventral hippocampal infusion of C20 ceramides did not cause the development of neuroinflammation. In conclusion, the direct infusion of C20 ceramides in the VH causes anhedonia-like behavior without further development of depressive-like behavior nor neuroinflammation in the VH. (Supported by: NIH-NIGMS 5R25GM082406 (PHSU RISE

Graduate Training Program), U54 MD007579 (B.R.A.I.N. and M.A.G.I.C. Core), NIGMS/INBRE P20GM103475, and NIH-NIGMS R25GM096955 (UPR-Ponce PRISE Program).

Presenter: Sebastián Castano-Pesante
Institution: San Juan Bautista School of Medicine
Title: Angiotensin II Stimulation in Microglial Cell Pro-Inflammatory Response: Role in Multiple Sclerosis.
Authors:

Abstract: Background: Angiotensin II (AngII) is the principal effector molecule of the renin-angiotensin-aldosterone system (RAAS). Its effects on the cardiovascular and renal system have been well-documented. AngII acts mainly by interacting with the AngII type-1 receptor (AT1R). Dysregulated levels of AngII lead to hypertension and cardiovascular disease. Increasing evidence suggests that AngII may also play a role in the pathophysiology of neurodegenerative diseases, such as multiple sclerosis (MS), through unclear mechanisms.

Objectives: Demonstrate that high levels of AngII contribute to the progression of MS by studying the activation of microglial cells in vitro.

Methods: To study AngII, AT1R, and AT2R levels in MS we used C57BL/6 mice with or without induced experimental autoimmune encephalomyelitis (EAE) and measured brain AngII and AT1R levels by Quantitative Polymerase Chain Reaction (qPCR). To investigate AngII's role in microglia activation, HMC3 cells were treated with AngII in presence or absence of AT1R antagonist, Losartan. The expression of the Inducible form of Nitric Oxide Synthase (iNOS) was measured using real time-PCR. Interleukin-6 (IL-6) and Tumor Necrosis Factor-α (TNF-α) levels were measured using ELISA. Nitric Oxide (NO) production was measured using Griess Reagent. ROS production was measured using the MUSE Oxidative Stress kit.

Results: In EAE mice, AngII and AT1R gene expression in brain tissue were significantly increased when compared to control mice (3.2 folds ±1.9, p<0.05, n=5; and 2.6 folds ±1.1, p<0.01, n=5 respectively). In addition, iNOS mRNA expression was likewise upregulated in EAE mice compared to their control counterparts (3.4 ± 1.4 folds, p<0.01, n=5). In HMC3 cells, treatment with AngII upregulated the gene expression of IL-6 (3.9 folds ± 1.2, p<0.01, n=4) and increased IL-6 concentrations by 83% (p<0.05, n=4). The changes in IL-6 were blocked by the AT1R antagonist, Losartan. Also, AngII induced the production of TNF-α, increasing its concentration by 90% (p<0.05, n=4), an increase that was also blocked by Losartan. In addition, NO and ROS production were significantly increased by AngII (p<0.05, n=4) and treatment with Losartan blunted their production (p<0.05, n=4). Finally, AngII treatment induced iNOS overexpression (2.5 folds ±0.8, p<0.05, n=4); results that are consistent with the increases seen in EAE mice.

Conclusions: These results suggest that AngII can activate microglial cell pro-inflammatory responses, which may contribute to the pathophysiology of CNS inflammation and MS.

Presenter: Francisco Rodríguez-Matos
Institution: Harvad Medical School
Title: Hypoxia and Endothelin-1 in Microglial Cell Activation.
Authors:Francisco Rodíguez-Matos, Sebastian Castaño-Presente, Jose R. Romero, PhD, Yaritza Inostroza-ieves, PhD

Abstract: Microglial cells are rapidly activated in response to injury and stressful stimuli, including hypoxia following ischemic brain injury. Endothelin-1 (ET-1), a potent vasoconstrictor, has been associated with cerebrovascular disease. Hypoxia stimulates endothelial ET-1 production. However, the role of ET-1 in microglia under hypoxia is not clear. The aim of this project was to characterize the effect of hypoxia in a human microglial cell line, HCM3. We induced hypoxia for 4h and measured effects 0h, 24h, and 48h after treatment. Immunofluorescence staining was performed to visualize ET-1 expression in hypoxic and control cells. MUSE Oxidative Stress Assay, ELISA, and qPCR were performed to compare ET-1 gene expression and ROS, TNF-α, and IL-6 production. It was observed that, when compared to normoxic HMC3 cells, hypoxic HMC3 exposure increased ROS production 2.5 times (p<0.001, n=3), TNF-α 3.8 times (p<0.01, n=4), and IL-6 1.6 times (p<0.01, n=4). In addition, hypoxia stimulated ET-1 gene expression 5.0-fold (p<0.001, n=4), and protein products 1.3 times (p<0.01, n=4). Consequently, treatment with exogenous ET-1 increased the amount of ROS, TNF-α, and IL-6 in normoxic HMC3 cells by a factor of 1.4 (p<0.05, n=4), 1.6 (p<0.001, n=4), and 1.9 (p<0.05, n=4), respectively. These events were blocked by ET-1 receptor antagonist (ETRA), BQ788. Our results suggest that hypoxic conditions create a cycle of microglial cell activation, leading to increased ROS and ET-1 production that further stimulate microglial cells. Thus, we posit that the ET-1 receptor blockade represents a promising therapeutic approach to regulate microglial cell responses in hypoxic-ischemic brain injury.

Presenter: Andrea Edwards Cintrón
Institution: Institute of Neurobiology at University of Puerto Rico, Medical Sciences Campus
Title: The Effects of Musical Education in Rhythmic Perception and Production in Puerto Rican Adults.
Authors: Mariana Rodríguez; Danilo Pérez; Andrea Ravignani; PI: Amaya Miquelajáuregui

Abstract: Our remarkable musical abilities seem to be rooted in biological principles and the inherent capacities of the human brain. In this study, we seek to understand the intrinsic rhythmic capabilities in Puerto Rican adults, as well as consider how musical education influences these abilities. To account for these skills, Puerto Rican adults (over 21 years of age), with or without musical training, participated in a series of rhythmic perception and production tests. The tests were the following: Metronome Synchronization, Free Tapping and the Montreal Battery of Evaluation of Musical Abilities (MBEMA). The rhythmic outputs were quantified by measuring the Inter Beat Intervals (IBI). We expect that musicians will display less variability and more accuracy in both rhythmic perception and production. Although all participants reflected a consistent rhythmic output, preliminary data reflects less variability in musicians during the rhythmic production tests when compared to non-musicians. In addition, the participants obtained an overall score of 85% or higher in the rhythmic perception test. This supports that although there seems to be inherent capabilities for rhythmic abilities, musical training may enhance these skills. In the future, we will assess these parameters in a group of children to shed light on the maturation of rhythmic abilities and the influence of musical training.


Presenter: Yancy Ferrer-Acosta, Ph.D.
Institution: Universidad Central del Caribe
Title: The Natural Compound 4R-Cembranoid and Memantine Share Similar Cholinergic Pathways to Induce Neuroprotection.
Authors:

Abstract: Memantine is an FDA-approved drug designed to treat patients with moderate to severe Alzheimers disease. Studies show that memantine is an uncompetitive antagonist of moderate affinity to the N-methyl-D-aspartate (NMDA) receptor. However, memantine's therapeutic role cannot be exclusively attributed to its effect on the NMDA receptor. Several studies have demonstrated its effectiveness as a neuroprotective agent by its ability to inhibit nicotinic receptors. In this study, we show additional evidence that memantines mechanism of action contains a cholinergic component. The pharmacological profile of memantines neuroprotective pathway was examined using ex-vivo hippocampal slices exposed to an excitotoxic NMDA insult and compared to the cyclic diterpene [(1S, 2E, 4R, 6R, 7E, 11E)-cembra-2,7,11-triene-4,6-diol], abbreviated here as 4R. 4R has a similar neuroprotective mechanism of action to memantine, although it is not an NMDA receptor antagonist, but a nicotinic modulator. In the ex-vivo paradigm, memantine induced neuroprotection when added before or after an NMDA insult. Interestingly, in the presence of the NMDA receptor antagonist APV, there was still 30% of neuroprotection from memantine that was not dependent on the NMDA receptor. This led us to further investigate the possible cholinergic neuroprotective mechanisms of memantine. The neuroprotection of both memantine and 4R against NMDA was completely inhibited in the presence of DHβE, an α4β2 nicotinic receptor antagonist. In the presence of the cholinergic vesicle release inhibitor vesamicol, memantine’s neuroprotection was significantly reduced by 25%. Therefore, the cholinergic component of both drugs was shown to be critical in their abilities to elicit neuroprotection. The neuroprotection by either drug was not affected when co-applied with a MEK1/2 inhibitor. Both 4R and memantine mediated neuroprotection through Akt/PI3K; however, after PI3K inhibition, 4R neuroprotection was blocked entirely, and memantines effect was 30% reduced. Memantine has a narrow neuroprotective range [1µM] against NMDA excitotoxicity, while 4R neuroprotection extends from 2 µM up to 40 µM. Having a similar mechanism of neuroprotection, we propose that the 4R cembranoid is potentially a better alternative than memantine to ameliorate the symptoms of Alzheimer’s Disease.

Presenter: Nadezhda Sabeva
Institution: Universidad Central del Caribe
Title: A toxicity study of (1S,2E,4R,6R,7E,11E)-cembratriene-4,6-diol in subcutaneously exposed Sprague Dawley rats.
Authors: Oné R. Pagán; Yancy Ferrer-Acosta;  Vesna A. Eterović; PI: P.A. Ferchmin

Abstract:

Presenter: Amanda Marie Díaz García
Institution: Universidad Central del Caribe
Title: HIV-1 Tat-mediated changes in the blood-retinal barrier.
Authors: Jadier Colón Vázquez PI; Astrid Zayas-Santiago

Abstract: In the eye's retinal tissue, inflammation during HIV-1 can cause visual impairment in 73% of patients, despite antiretroviral therapy's success. The HIV viral load is often detected in patients' ocular fluids and retinal tissue. Therefore, understanding HIV's effect on the blood-retinal barrier (BRB), which could allow for its retinal invasion, is of great importance. The BRB is a selective barrier regulating fluids and nutrients between the vascular bed and the retina, and it is divided into inner-BRB (iBRB) and outer-BRB (oBRB). The iBRB consists of a continuous endothelial cell layer resting on a basal lamina covered by pericytes and Müller glial cell processes and the oBRB consists of retinal pigment epithelial cells (RPE) held by tight junctions resting on an underlying membrane. The junctional integrity of the BRB can be affected by many factors when targeted by HIV. HIV-Tat is a transactivator protein essential in both HIV replication and infection pathogenesis. Studies in vitro revealed that HIV-Tat affects the RPE/oBRB's permeability and tight junction expression. Also, HIV-Tat induces apoptosis and activates proinflammatory cytokines in retinal cells in vitro. Still, the exact mechanism underlying the role of Tat in the invasion of HIV in the retina remains unknown. The purpose of our study was to investigate how HIV-Tat affects the iBRB and the oBRB. We used a localized HIV eye model developed by injecting 2.5ng/μL of HIV-Tat B protein into a rats' vitreous, maintained for five days. After HIV-Tat treatment, we evaluated physiological changes in the BRB with immunohistochemical analysis of glial cell markers: glial fibrillary acidic protein (GFAP), glutamine synthetase (GS), aquaporin 4 (AQP4), and potassium (K+) channel Kir4.1; BRB marker: intercellular adhesion molecule (ICAM-1); and inflammation markers: interleukin-1 beta (IL-1β) and tumor necrosis factor-alpha (TNFα) visualized with confocal microscopy. A membrane-based antibody array was also performed to measure cytokines and chemokines in the treated retinal tissues compared to control. The goal was to characterize both BRB components in response to HIV-Tat since most studies have concentrated on changes in the tight junctions and validate our model for this study. Results show an increase in proinflammatory cytokines IL-1β and TNFα by immunofluorescence and thymus and fractalkine chemokines by proteome array. Also, the upregulation of intercellular adhesion molecule-1 (ICAM-1), a vital ligand for monocytes' recruitment into the tissues, was observed with both immunofluorescence and proteome array. In the iBRB, changes included enlargement of blood vessels and overexpression of potassium channel Kir4.1 and GFAP, demonstrating changes and reactivity in Müller-glial cells. In conclusion, inflammatory mediators present because of HIV-Tat treatment seem to induce ICAM-1 upregulation in RPE/oBRB). These results suggest that ICAM-1 could be a promoter of HIV-infected monocytes to the RPE cells, facilitating viral load invasion into the ocular tissues during HIV. However, it still needs to be further investigated. Additionally, the malfunction of glial cells in the iBRB could also play a role in this event.

Presenter: Karl Y. Bosque-Cordero
Institution: University of Puerto Rico Rio Piedras Campus
Title: Ih blocker (ZD7288) reduces cocaine-induced firing patterns on putative dopaminergic neurons of the ventral tegmental area.
Authors: Rafael Vazquez-Torres Cristhian Calo-Guadalupe Daisy Consuegra-Garcia Giulia Fois Francois PI: Georges Carlos A. Jimenez-Rivera

Abstract: The hyperpolarization-activated cation current (Ih) is a determinant of intrinsic neuronal excitability in various cells, including dopaminergic neurons (DA) of the ventral tegmental area (VTA). In contrast to other cellular conductances, the Ih activates through hyperpolarizing voltage steps to potentials negative to -55mV and depolarizes the membrane potential. Our laboratory demonstrated that cocaine sensitization, a chronic cocaine behavioral model, significantly reduces Ih amplitude in VTA DA neurons (Arencibia-Albite et al., 2012). After the development of cocaine sensitization, the spontaneous firing of VTA DA cells remains similar to control groups. Suggesting that Ih reduction could reduce cocaine-induced excitability as a homeostatic adaptation for neuronal excitability, although this relationship is still poorly understood. Through in vivo anesthetized single-unit extracellular electrophysiology, we explore the contribution of the Ih on VTA DA neurons spontaneous firing patterns. A key feature of evaluating spontaneous excitability is the detection of bursting activity. Bursting is defined as trains of two or more spikes occurring within a short interval and followed by a prolonged period of inactivity. Burst formation increases the reliability of information transfer. Rhythmic burst firing in thalamic relay neurons arises mainly from the interaction of two dominant currents, Ih and T type Calcium Channels (lt) (McCormick & Pape, 1990). The Ih activation depolarizes the membrane potential towards threshold activating It and generating a low-threshold Ca2+ spike.  The generation of this Ca2+ spike activates a burst of fast Na+ and K+ dependent action potentials. This provides a possible mechanism on how Ih could influence burst firing in VTA DA neurons. To elucidate the contribution of Ih on VTA DA neurons spontaneous firing patterns, we perfused Ih blocker (ZD 7288, 8.3 μM) and evaluated its effect. Ih blockade significantly reduced firing rate, bursting frequency, and percent of spikes within a burst on VTA DA neurons. Using whole-cell patch-clamp, we determine the progressive reduction of the Ih after acute and chronic cocaine administration (15mg/k.g). In addition, Ih blockade significantly reduced acute cocaine-induced firing rate, bursting frequency, and percent of spikes within a burst on the low firing/high bursting VTA DA neuron group. These data suggest that the progressive reduction of Ih could serve as a homeostatic regulator of cocaine-induced spontaneous firing patterns related to VTA DA excitability. Support: National Institute of General Medical Sciences (2SC1GM084854) National Center for Research Resources (5R25GM061838-15, 2G12-RR003051) National Institute on Minority Health and Health Disparities (8G12-MD007600) NSF Partnerships in International Research and Education (PIRE) program Neural Mechanisms of Reward & Decision (OISE-1545803) Research initiative for Scientific Enhancement RISE (5R25GM061151-18)

Presenter: Valeria De La Rosa-Reyes
Institution: University of Puerto Rico- Medical Sciences Campus
Title: Retinoic acid application transiently increases microglia and macrophages populations after optic nerve injury in Rana pipiens.
Authors: Mildred V. Duprey-Díaz Jonathan M. Blagburn PI: Rosa E. Blanco

Abstract: Retinoic acid (RA) plays major roles during nervous system development, and during regeneration of the adult nervous system. We have previously shown that RA signaling pathway components are upregulated after optic nerve injury and that exogenous application of RA greatly increases the survival of axotomized retinal ganglion cells (RGCs). The objective of the present study elucidate the role of RA application on macrophages and microglia populations as well as axonal regrowth in the optic nerve after injury. We performed optic nerve crush and applied to the nerve either saline solution, retinoic acid or clodronate liposomes. We examined the optic nerves at one week, and two weeks, after axotomy with immunocytochemistry and electron microscopy. Our results show that application of RA to the optic nerve causes a significant increase in the number of macrophages and microglia one week after optic nerve injury. The macrophages present have considerable phagocytic activity and are consistently labeled with M2-type macrophage markers. Numbers of activated microglia also increase near the injury site. Two weeks after axotomy and RA treatment there are fewer macrophages, and their ultrastructure shows less phagocytic activity. Clodronate liposome treatment at the time of axotomy apparently eliminates the macrophages present in the nerve at one week. We measured RGC survival at six weeks after axotomy and clodronate treatment and found no obvious effect of this treatment. We have seen that RA application has an effect improving axonal regrowth at 2 weeks after injury. In conclusion, the application of retinoic acid increases the number of macrophages and microglia present in the nerve after optic nerve injury. Further studies will explore if this effect plays a role in the success of optic nerve regeneration.

Presenter: Orlando Iván Torres-Rodríguez
Institution: Ponce Health Sciences University/Ponce Research Institute
Title: ICV administration of P2X7 antagonist prevents SPS-induced PTSD-related behavior in male and female rats.
Authors: Orlando Iván Torres-Rodríguez, PI: James T. Porter

Abstract: Clinical evidence has linked increased peripheral levels of pro-inflammatory cytokines with the severity of PTSD symptoms. Since microglia are known as a major producer of pro-inflammatory cytokines in the brain, the inflammatory manifestation mediated by microglia may contribute to PTSD-related behaviors. We hypothesized that stress exposure induces a microglial-mediated inflammation that precedes the PTSD behavioral manifestations. To test this, we exposed rats to single prolonged stress (SPS) one week before measuring fear discrimination, extinction, and anxiety-like behaviors. Consistent with the literature, our data show that exposing rats to SPS produces a PTSD-like phenotype of impaired fear extinction and increased anxiety in male and female rats. Additionally, SPS-exposed animals showed increased expression of Iba-1, and P2X7R by microglia in the ventral hippocampus (VH), a structure that regulates fear extinction and anxiety. Furthermore, VH microglial increased their expression of IL-1β and TNF-α genes three days following SPS suggesting an increased inflammatory-state before behavioral testing. Although our data suggest that SPS induces an inflammatory manifestation mediated by microglia, it is not clear whether inhibition of the inflammation will prevent the SPS-induced PTSD-related behaviors. Since P2X7R are primarily expressed by microglia, we hypothesized that inhibition of inflammatory P2X7R signaling would prevent the SPS-induced PTSD-related behaviors. To test this hypothesis, we implanted Intracerebroventricular (ICV) cannulas into the animals 2 weeks before SPS exposure for the administration of the P2X7R antagonist, A-438079. Animals were randomly assigned and received one week of daily infusions of the vehicle or A-438079 starting the day of SPS exposure. Then, animals were subjected to a behavioral paradigm to examine cue-associated fear discrimination, fear extinction, and anxiety. Our results indicate that animals that received A-438079 showed improved extinction and less anxiety-like behaviors. Consistent with our hypothesis, inhibition of the P2X7R prevented the SPS-induced impaired fear extinction and increased anxiety-like behaviors in male and female rats. Altogether, these data suggest that inhibiting inflammatory responses, such as P2X7R signaling in microglia, following trauma exposure might prevent the development of trauma-associated neuropsychiatric disorders such as PTSD.

Presenter: Felix Rivera Moctezuma
Institution: Universidad Central del Caribe
Title: A cyclic diterpenoid has a neuroprotective effect against Gulf War Illness involved neurotoxicants.
Authors: Rivera-Moctezuma Félix G. Perez Dinely Ferchmin Pedro PhD. PI: Sabeva Nadezhda PhD.

Abstract: Organophosphate (OP) compounds have been widely used as agricultural and household pesticides, jet engine lubricants, and warfare nerve agents. Therefore, the general population and military personnel could be exposed to OPs not only during combat or terroristic attacks but also during the routine military, industrial or private activities. Delayed neuronal damage of the OP intoxication is thought to contribute to neuronal death and various neurological illnesses. Gulf War Illness (GWI) is one of them. GWI is a currently untreatable multi-symptom disorder experienced by more than 250,000 veterans from the Persian Gulf War (1990-1991). The distinctive hallmark of GWI includes chronic fatigue, migraine, muscle and joint pain, gastrointestinal problems, and cognitive disturbances such as depression and anxiety. Various studies have consistently linked these symptoms to exposure to pyridostigmine, DEET, permethrin, and traces of sarin (the most commonly used nerve agent). There is no effective cure for the GWI or the chronic effect of other neurotoxicants. Our group demonstrated ex vivo that exposure to diisopropylfluorophosphate (DFP, a surrogate of sarin) and the above-mentioned neurotoxicants reduce the number of functionally active neurons in hippocampal slices. This loss of neuronal functionality can be reversed by the application of a 4R-cembranotrienes-diol (4R), a cyclic diterpenoid, with anti-inflammatory and anti-apoptotic properties. The cembranoid is not toxic and reaches higher concentrations in the brain than plasma. We took advantage of our ex vivo GWI model (rat hippocampal slices) to investigate whether 4R has a protective effect on synaptic integrity and neuronal survival in the presence of DFP. We combined electrophysiological recordings with molecular and histological ultrastructural analysis on acute hippocampal slices. Our results suggest that 4R protects the integrity of dendrites and activates AKT/PI3K cell survival pathway. Thus, this cembranoid is a promising compound to protect the nervous system against neurotoxicants.

Presenter: Orlando Iván Torres-Rodríguez
Institution: Ponce Health Sciences University/Ponce Research Institute
Title: ICV administration of P2X7 antagonist prevents SPS-induced PTSD-related behavior in male and female rats.
Authors: Orlando Iván Torres-Rodríguez        
PI: ames T. Porter

Abstract: Clinical evidence has linked increased peripheral levels of pro-inflammatory cytokines with the severity of PTSD symptoms. Since microglia are known as a major producer of pro-inflammatory cytokines in the brain, the inflammatory manifestation mediated by microglia may contribute to PTSD-related behaviors. We hypothesized that stress exposure induces a microglial-mediated inflammation that precedes the PTSD behavioral manifestations. To test this, we exposed rats to single prolonged stress (SPS) one week before measuring fear discrimination, extinction, and anxiety-like behaviors. Consistent with the literature, our data show that exposing rats to SPS produces a PTSD-like phenotype of impaired fear extinction and increased anxiety in male and female rats. Additionally, SPS-exposed animals showed increased expression of Iba-1, and P2X7R by microglia in the ventral hippocampus (VH), a structure that regulates fear extinction and anxiety. Furthermore, VH microglial increased their expression of IL-1β and TNF-α genes three days following SPS suggesting an increased inflammatory-state before behavioral testing. Although our data suggest that SPS induces an inflammatory manifestation mediated by microglia, it is not clear whether inhibition of the inflammation will prevent the SPS-induced PTSD-related behaviors. Since P2X7R are primarily expressed by microglia, we hypothesized that inhibition of inflammatory P2X7R signaling would prevent the SPS-induced PTSD-related behaviors. To test this hypothesis, we implanted Intracerebroventricular (ICV) cannulas into the animals 2 weeks before SPS exposure for the administration of the P2X7R antagonist, A-438079. Animals were randomly assigned and received one week of daily infusions of the vehicle or A-438079 starting the day of SPS exposure. Then, animals were subjected to a behavioral paradigm to examine cue-associated fear discrimination, fear extinction, and anxiety. Our results indicate that animals that received A-438079 showed improved extinction and less anxiety-like behaviors. Consistent with our hypothesis, inhibition of the P2X7R prevented the SPS-induced impaired fear extinction and increased anxiety-like behaviors in male and female rats. Altogether, these data suggest that inhibiting inflammatory responses, such as P2X7R signaling in microglia, following trauma exposure might prevent the development of trauma-associated neuropsychiatric disorders such as PTSD.

Presenter: Cristina Suárez-Gómez
Institution: Ponce Research Institute
Title: The effects of early-life neglect and adolescent cocaine use on PTSD-related behaviors in adult rats.
Authors: Keudes Roldán-Rodríguez Anixa Hernández-López María C. Colón-Romero
PI; Dr. James T. Porter

Abstract: Studies suggest that childhood abuse, cocaine addiction, and posttraumatic stress disorder (PTSD) may interact in minority populations and likely contribute to worse outcomes and health disparities. Most animal studies focus individually on models of cocaine use or PTSD to study these disorders. However, the clinical population frequently shows comorbid PTSD and cocaine use. In this project, we combined an animal model of early-life neglect with models of cocaine use and PTSD to examine whether these factors interact to increases the severity of PTSD-like phenotypes. Male and female Sprague Dawley rats were exposed to maternal separation from P1 to P14 and then received cocaine conditioned place preference (CPP) during adolescence. In adulthood rats received auditory fear conditioning and extinction. We hypothesized that the early life neglect and adolescent cocaine use would interact to increase PTSD-like behaviors in adulthood. We found that maternal separation impaired cocaine CPP in both sexes. Therefore, this short-duration early-life neglect impaired reward learning during adolescence. However, when tested as adults, maternal separation or adolescent cocaine CPP alone or combined did not alter anxiety-like behavior in the open field test in either sex. Similarly, all groups showed similar acquisition and extinction of auditory fear conditioning in males and females. Therefore, we did not find any lasting effects of the short-term early-life neglect or the adolescent cocaine exposure on either anxiety or fear learning and extinction. We also examined the expression of basic fibroblast growth factor (FGF-2) in infralimbic cortex of these groups. Consistent with the behavior data, we did not find any differences in FGF-2 expression. Overall, our finds suggest that PTSD-related behaviors in adult rats of both sexes are resilient to mild early-life neglect even if combine with mild adolescent cocaine use.

Presenter: Maria Elisa Ramírez Román
Institution: University of Puerto Rico, Rio Piedras Campus
Title: Effect of alcohol on sleep patterns in Drosophila melanogaster.
Authors: Genesis A. Ayala-Santiago, José L. Agosto, PI: Dr. Alfredo Ghezzi

Abstract: Alcohol consumption is known to affect many physiological processes necessary for the proper functioning of the organism. In the brain, alcohol binds to several molecular targets to produce an overall suppression of neuronal activity. This leads to a series of neuroadaptive mechanisms implemented to counterbalance ethanol-induced neuronal suppression and help the system restore homeostasis. These neuroadaptive changes have been associated with the development of alcohol tolerance, dependence and ultimately addiction. In addition, these adaptations are also believed to be the root of a series of sleep disturbances, which often manifest during the development of alcoholism. As both, alcohol addiction and sleep regulation are under homeostatic control, we hypothesize that these processes share a common mechanism. Here, we use Drosophila melanogaster as a biological model to study alcohol-sleep responses. After exposing flies to ethanol vapor until they are sedated and analyzing their sleep pattern with the DAM system, we observe that alcohol increases sleep during the day but diminishes sleep during the night. In a 24 hour interval that includes both day and night, we observe no change in total sleep after ethanol exposure. We believe that these results reflect a homeostatic mechanism where the effect of ethanol on sleep during the day is counterbalanced to the effect during the night. For future studies, we think that integrating the use of genetic analyses with physiological modulation of neural activity within specific sleep circuits has tremendous potential to uncover the functionally relevant molecular targets whose action contributes to the deleterious effect of alcohol on sleep.

Presenter: Andrea Maldonado Santiago
Institution: University of Puerto Rico-Rio Piedras Campus
Title: The Role of Microglia of Aging Niemann Pick Type C Disease Mice.
Authors: Andrea Maldonado Santiago; PI: Rosa E. Blanco ; Valeria de la Rosa Reyes; Illeana Soto ;Clarissa del Cueto

Abstract: Niemann Pick-Type C disease is an inherited lysosomal storage disease caused by Npc1 and Npc2 deficient genes. It is typically observed in infants who present symptoms involving loss of brain functions or abilities and can lead to dementia or early death. Previous work has shown that the Npc1 mutation produces retinal degeneration including vision impairment and an increase in autophagy markers in the ganglion cell layer.2 Also it has been demonstrated that microglia and macrophages are activated in certain parts of the brain of mutant animals. In general, phagocytic cells play a crucial role in neuroinflammation and neuro-regeneration. However, their role in the degeneration of the retina in Npc1 mutants is not well understood. The objectives of this investigation are to describe the changes in microglial cells in the retina of Npc1 mice with increasing age and describe the interactions with retinal ganglion cells (RGCs). Immunofluorescence staining with specific antibody markers was used to identify microglia and macrophages. Cell counting and data analysis were carried out with ImageJ/Fiji to compare phagocytic cell populations between retinas of Npc1 mutant mice and wildtype mice. Our preliminary results show that RGCs labelled with Thy antibody decreased in number in the retina of old Npc1 mice. A large increase in microglia labelled with Iba1 was also observed in the retinas of older mutant mice. Our preliminary conclusion is that the death of RGCs in retinas of old Npc1 mice correlates with an increase in microglia, which we hypothesize are phagocytosing the neurons. Further ultrastructural studies are necessary to confirm this.

Presenter: Dariangelly Pacheco Cruz
Institution:Pontifical Catholic University of Puerto Rico
Title: MeHg exposure downregulates GABAA receptor subunit expression in rat forebrain.
Authors: Alexandra Colón-Rodríguez, PhD Kimberly Rivera-Caraballo
PI; William Atchsion, PhD

Abstract: Methylmercury (MeHg) is the most toxic form of mercury (Hg). It affects the central nervous system in acute and chronic exposure and has been associated with epileptogenesis (generation of seizures). MeHg impairs GABAA receptor function leading to hyperexcitability in different neuronal populations, and GABAA impaired function leads to seizure susceptibility. However, it is not known if MeHg leads to changes in gene expression of this receptor, presenting a possible way by which MeHg could be leading to hyperexcitability and epileptogenesis. The goal of this project was to identify if MeHg exposure leads to an alteration on gene expression of the most common GABAA receptor subunits in the forebrain. We hypothesized that MeHg exposure would cause downregulation of all GABAA receptor subunits studied. To address this we exposed postnatal day 4 male Sprague Dawley rats to 0, 0.75, or 1.5 mg/kg/day MeHg via subcutaneous injection. Exposure occurred for 15 or 30 days, and a treated group of 30 day was left untreated for an additional 30 days (60 days). RNA extraction was performed on forebrain tissue, then RT-PCR and qPCR were performed. Our results show significant differences (p value = 0.0024) between the groups of 15, 30 and 60 days, where it was noted that there was a downregulation of the ɑ1 and β1,3 subunits at 30 days. Although we observed that MeHg causes downregulation of the GABAA receptors, more studies are needed to elucidate if this downregulation is expressed at the protein expression levels, and the mechanisms involved. Our results contribute to the understanding of MeHg-induced impaired function of GABAA receptors and the underlying mechanisms by which MeHg could be contributing to seizure susceptibility.

Presenter: Emmanuel Cruz
Institution:Pontifical Catholic University of Puerto Rico
Title: CIM6P/IGF-2 Receptor Ligands Reverse Deficits in Angelman Syndrome Model Mice.
Authors: Emmanuel Cruz Giannina Descalzi Adam Steinmetz Helen E. Scharfman Aaron Katzman PI: Cristina M. Alberini

Abstract: Abstract: Angelman syndrome (AS), a genetic disorder that primarily affects the nervous system, is characterized by delayed devel- opment, intellectual disability, severe speech impairment, and problems with movement and balance (ataxia). Most affected children also have recurrent seizures (epilepsy). No existing therapies are capable of comprehensively treating the deficits in AS; hence, there is an urgent need to identify new treatments. Here we show that insulin-like growth factor 2 (IGF-2) and mannose-6-phosphate (M6P), ligands of two independent binding sites of the cation-independent M6P/IGF-2 receptor (CIM6P/IGF-2R), reverse most major deficits of AS modeled in mice. Subcutaneous injection of IGF-2 or M6P in mice modeling AS restored cognitive impairments as assessed by measurements of contextual and recognition memories, motor deficits assessed by rotarod and hindlimb clasping, and working memory/flexibility measured by Y- maze. IGF-2 also corrected deficits in marble burying and significantly attenuated acoustically induced seizures. An obser- vational battery of tests confirmed that neither ligand changed basic functions including physical characteristics, general behavioral responses, and sensory reflexes, indicating that they are relatively safe. Our data provide strong preclinical evi- dence that targeting CIM6P/IGF-2R is a promising approach for developing novel therapeutics for AS. Funding: This work was supported by the Foundation for Angelman Syndrome Therapeutics (FAST), NIH grant MH065635 to C.M.A., NIH grant T32MH019524 and T32AG052909 to E.C., a Canadian Institutes of Health Research Fellowship to G.D., and F31MH116585 to A.K.

Presenter: Yesenia Castillo-Ocampo
Institution: Ponce Health Sciences University
Title: GluN3B expression at vHPC-IL after fear-related behavior.
Authors:

Abstract: The fear circuit involves connections between the ventral hippocampus (vHPC) and the infralimbic cortex (IL). The vHPC routes information about the environment to IL which modulates the expression of fear via the amygdala. Although IL is not thought to play a role in fear conditioning, recent experiments suggests that synaptic plasticity is occurring in IL during auditory fear acquisition as measured by changes in the NMDA receptor-mediated currents in male rats. Based on our laboratory's previous electrophysiological studies, wehypothesized that fear conditioning alters NMDA receptors on vHPC-to-IL synapses in rats. To evaluate synaptic changes in NMDA receptors at this specific synapse, we injected AAV particles expressing EYFP into the vHPC of male and female rats to label vHPC projections with EYFP. Since less is known about the GluN3B subunit of NMDA receptors we evaluated changes in GluN3B. To test for NMDA receptor changes in the vHPC-to-IL synapses after fear learning, we used fluorescence active cell sorting (FACS) to quantify synaptosomes isolated from IL tissue punches that were positive for EYFP and GluN3B. We compared rats exposed to auditory fear conditioning, extinction, or pseudoconditioning. Females and males showed similar freezing behavior and similar levels of EYFP+/GluN3B+ IL synaptosomes that did not vary with behavior. EYFP+/GluN3B+ synaptosomes were more abundant in larger synaptosomes. These findings suggest that GluN3B is in the post-synaptic membrane of vHPC-to-IL synapses but is not altered by auditory fear conditioning or extinction.  

Presenter: Dianiris Astacio Rodríguez
Institution: Pontifical Catholic University of Puerto Rico
Title: Effects of stress and exercise on CRH levels in a Sprague Dawley rat model of endometriosis
Authors: Dariangelly Pacheco Cruz, Myrella L. Cruz, Gladys Chompre
PI: Caroline Appleyard

Abstract: Endometriosis is a debilitating disease, characterized by growth of endometrial tissue in areas outside the uterus, that can cause painful cramps, vomiting, and infertility. 1 out of every 10 women of reproductive age have endometriosis. Environmental factors, such as stress, can exacerbate endometriosis through impact on the Hypothalamic-Pituitary-Adrenal (HPA) axis. One of the main signaling peptides from the HPA axis is corticotropin releasing hormone (CRH). The aim of this project is to study the variations in CRH levels in the brains of rats with endometriosis exposed to stress and exercise, and their effect on the development of endometriotic lesions. We hypothesize that exercise alleviates endometrial lesions by the inhibition of central gonadotropin releasing hormone via CRH mechanisms. CRH levels will be measured in different cells in the brain using immunofluorescence and immunohistochemistry staining. We expect to find reduced endometriotic lesions in the rats exposed to stress and exercise, larger lesions in rats exposed only to stress, and significantly lower lesions in rats that were only exercising. In the brain we expect to see reduced levels of CRH in the endometriosis rats exposed to stress and exercise with endometriosis, higher levels of CRH in those exposed only to stress, and lower levels of CRH in rats that were only exercising. Supported in part by R15AT009915

Project Presentation

Presenter: Carmen Maldonado-Vlaar, Ph.D.
Institution: University of Puerto Rico, Rio Piedras Campus
Title: A multidimensional and virtual summer research training program in the Neurosciences for undergraduate students from underrepresented backgrounds at a Hispanic Serving Institution.
Authors: Carmen Maldonado-Vlaar, José García-Arrarás, Edjean M. Calderón-Cruz and John J. Ramiréz-Leiton.

Abstract: NeuroID is a program designed to increase diversity in Neuroscience by providing opportunities to undergraduate students interested in this area and enhance their scientific knowledge, research capability, and social responsibility. This Summer we will have available a  multidimensional and virtual summer research training program in the Neurosciences for undergraduate students. The presentation will allow you to learn more about this very valuable program.

Presenter: Aaron Matos
Institution: Polytechnic University of Puerto Rico
Title: Development of a transradial myoelectric prosthesis controlled by EMG
Authors: Rafael A. Álvarez González
PI: Aaron Matos

Abstract: Electromyography (EMG) is a bioelectric recording technique of the skeletal muscle. This technique allows the diagnosis and analysis of neuromuscular diseases, rehabilitation, the control of active devices and allows giving functional electrical stimulation schemes. In the development of active devices are myoelectric prostheses. Myoelectric prostheses are systems driven by servomotors; these are controlled by electromyography signals (EMG) which are intramuscular. There are sensors that can used by means of needles or electrodes placed in the residual area of the patient and thus allowing them to capture the signal superficially. This work shows the development of a trans radial myoelectric prosthesis that will be developed with the implementation of a vacuum assisted suspension (VAS). The electronic part of the project will be carried out with the Arduino microprocessor to control the muscular electrical activity.

Presenter: Loyra B Rodríguez Muñoz
Institution:Carlos Albizu University
Title: Correlation between Adverse Childhood Experiences and Alcohol Use Among College Students in Puerto Rico.
Authors: Loyra B Rodríguez Muñoz and Cristina Velázquez-Marrero, Ph.D.

Abstract: Adverse childhood experiences (ACE) are a set of negative experiences prior to 18 years old that determine possible development of adulthood risk factors (Felitti et al., 1998). Hispanics have been known to be susceptible to ACE exposure. This research project aims to study ACEs as a possible predictor to excessive alcohol use in Puerto Rican college students. We predict that the higher the ACE count is for a participant, the higher the probability for substance abuse, as sustained by literature.

Presenter: Wickensonn Norze
Institution: University of Puerto Rico Rio Piedras
Title: A crosstalk between Transient Receptor Potential Vanilloid 1 and Cannabinoid receptor 1within the limbic system regulates anxiety and depression-like behaviors triggered by stress in rats.

Abstract: Clinical studies provide strong evidence that stress is an environmental risk factor that can trigger the onset of several neuropsychiatric disorders such as anxiety and depression in humans. Pre-clinical evidence suggests that the endocannabinoid and endovanilloid system within the brain are important neuronal substrates involved in emotional responses to stress. Specifically, studies have proposed that the Transient Receptor Potential Vanilloid 1 (TRPV1) a member of the Transient Receptor Potential (TRP) superfamily, within the brain regulate anxiety and depression behaviors through its interactions with the cannabinoid receptor 1 (CB1R). However, little is known about the cellular mechanisms that regulate these receptors’ interactions across the brain and its impact in neuropsychiatric disorders. We investigated the role of TRVP1R and CB1R within several brain regions including the medial prefrontal cortex as part of the dopamine mesocorticolimbic system, the hippocampus and the amygdala in anxiety and depression like-behaviors using rats as animal model. To modulate depression like-behavior, male Sprague Dawley rats were experienced a pretest session for 15 min, followed 24 h later by a 6 min test session in order to examine the effects of blockade of FAHH and its association with the olvanil in depression-like behaviors. One group of animals (acute exposure) received a single dose of URB597 [ 0; 0.1 ;0.2mg/kg/ip] 2 hours before testing in the FST for 6 min. The other group were treated for 4 days (repeated exposure) at the same doses. In order to examine the effects of the association of blockade of FAHH and the olvanil in depression like-behaviors, animals were treated for 4 days (repeated exposure) with URB597 [ 0; 0.1 ;0.2mg/kg/ip] and Olvanil [0; 0.3; 0.5 mg/kg/ip] only the last day (day 4th ) 2 hours before testing in the FST for 6 min to evaluate time spend in floating and swimming. However, to evaluate anxiety behavior, rats will be exposed to a repeat exposure for 4 days with either vehicle or URB597 at dose [0; 0.1mg;0.2mg/kg/ip] and Olvanil at dose [0; 0.3; 0.5 mg/kg/ip] only the last day (day 4th) 90 min before exposed to 30 min acute restraint stress followed by 15 min light dark box test in order to measure the anxiety response. Our results suggest that the repeated exposure of URB597 significantly decreased depression like-behavior and tend to increase depression like-behavior when URB597 is associated with the olvanil. Ongoing biochemical analysis of the changes in expression of TRPV1 and CB1 receptors following treatment with URB597 alone and when it is associated with the olvanil will support mechanistic explanations for the present behavioral results. Keywords: CB1 receptors,TRPV1 receptors,Anxiety,Depression,Endocannabinoids Funding support: This research was supported by NIDA, Grant# 1R15 DA044500-01A1 to CS Maldonado Vlaar, No financial interests or potential conflicts of interests have biased these studies

Presenter: Julienn Rodriguez
Institution:Pontifical Catholic University of Puerto Rico, Ponce Campus
Title: Methylmercury Alters Gene Expression of AMPA Receptors Subunits on hiPSC-MNs
Authors:
PI: Dr. Alexandra Colón-Rodríguez; Kimberly Rivera-Caraballo; Dr. William Atchison

Abstract: Methylmercury (MeHg), is the most encountered form of mercury. Hg widespread use, environmental sources, and its biomethylation by sulfate-reducing bacteria in bodies of water, generate MeHg. Then it enters the food chain and humans are exposed through contaminated fish consumption. MeHg causes sensory and motor dysfunction, and it is known that α-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid receptor (AMPAR) is associated with the MeHg induced cell death possibly due to excitotoxicity. AMPAR are responsible for primary depolarization in glutamate-mediated neurotransmission. It has been reported that MeHg affects motor neurons (MNs) by increasing the intracellular [Ca2+] which occurs through AMPAR. To explore this possibility, we used human-induced pluripotent stem cell derived motor neurons (hiPSC-MNs). We specifically aimed to determine whether acute MeHg exposure, at toxicologically relevant concentrations, increased or decreased gene expression of AMPAR subunits. To achieve this, we exposed hiPSC-MNs to 0.1, 0.2, 0.5, 1.0 and 1.5 μM MeHg for 1 hour. To assess gene expression, we carried out reverse transcription and quantitative real-time PCR on RNA isolated from hiPSC-MNs either immediately or 24 hours after exposure. Immediate expression after exposure shows that there is an increase of expression of all the subunits at 0.1 μM through 1.5 μM MeHg exposure. Gene expression measured 24hr after a 1hr MeHg exposure shows a decrease in expression at all concentrations, except the lowest concentrations (0.1 μM) . In summary, our results demonstrate that MeHg causes a differential effect in the expression of the AMPAR subunits in a human cell model. These preliminary results are relevant because this is the first study that demonstrates that MeHg affects gene expression of AMPA receptors in a concentration-dependent manner a human cell model.

Presenter: Eduardo Díaz Vega
Institution: Escuela Superior Vocacional Bernandino Cordero Bernard
Title: Designing, Fabrication and Characterization of a Feedback SmartSock Neurobionic Sensor
Authors: Alexaida Mercado, P.I. Eduardo Díaz Vega

Abstract: Human gait monitoring by means of plantar foot pressure measurements could have numerous applications, such as postoperative rehabilitation and recovery assessment, detection of abnormal gait conditions, monitoring of foot surface pressure for diabetic patients and many more.

Presenter: Eliezer Cartagena
Institution: Institute of Neurobiology
Title: Ethanol modulation of surface expression of the BK channel is isoform specific.
Authors: Eliezer Cartagena and Cristina Velázquez-Marrero, Ph.D.

Abstract: Alcohol increases the activity of the large conductance Ca2+ - and voltage-activated K+ channel (BK) at physiologically relevant concentrations. We have previously described two membrane trafficking components that lead to the development of molecular tolerance to EtOH: 1) de-clustering and 2) internalization of the BK channel. Both of these components are seen in neurons and transfected HEK 293 cells. Our laboratory has found that after 6-hrs of ethanol exposure the mRNA of the EtOH-insensitive isoform, STREX, replaces the EtOH-sensitive isoform, ZERO. Here, we extend our studies performed at the level of RNA message to the protein level. We test the hypothesis that the surface expression of BK channel isoforms (Zero and STREX) is differently modulated by exposure to EtOH. We use TIRF imaging, along with electrophysiological techniques, to examine the internalization and de-clustering of these two protein isoforms after incubation with EtOH. First, we observed that in stably transfected HEK 293 cells expressing the ZERO isoform, the channel is internalized and de-clustered after EtOH exposure when compared to controls. In contrast, HEK cells expressing the STREX isoform show no significant internalization or de-clustering of the channel. To determine whether these EtOH-induced changes in membrane expression of the BK channel occur in a neuronal preparation, we used hippocampal neurons, which endogenously express the ZERO and STREX isoforms. We performed immunofluorescence against all endogenous BK channel isoforms, and live-cell imaging experiments using GFP-tagged constructs with particular BK channel isoforms, enabling us to monitor changes in isoform-specific membrane expression. The immunofluorescence results revealed a time-dependent modulation in the surface expression of the endogenous population of BK by EtOH. The data showed a significant decrease in surface expression after 6-hrs of EtOH incubation. By contrast, this reduction was not seen in the GFP-tagged STREX isoform. These results indicate that protein expression of different isoforms of the BK channel are distinctively regulated in the plasma membrane after EtOH exposure in both heterologous expression systems and neuronal preparations. Interestingly, our results suggest that in addition to isoform specificity in response to acute ethanol exposure, plasticity in the response to longer-term ethanol treatment also differs as a function of isoform identity.

Presenter: Paula Muñoz-Rodríguez
Institution: University of Puerto Rico-Rio Piedras Campus
Title: The effects of oxytocin intranasal administration in exercise and anxiety-like behaviors in rats.
Authors: Paula A. Muñoz-Rodríguez, Lester G. Rodríguez-Santos, Astrid Ramos-Rolón, Wickensonn Norzé, Valerie S. Encarnación-Cortés, Laura L. Méndez-Santacruz, Jesús M. Padilla-Escalona and Eladdie M. Olmedo-López. P.I. Carmen S. Maldonado-Vlaar

Abstract: Oxytocin (OT) is a neuropeptide primarily synthesized in the hypothalamus associated with social behaviors, stress responses and drug-addiction. A previous study showed a cross-talk between the CB1R of the endocannabinoid system (ECS) and OTR within the mesolimbic system to modulate anxiety behavior. Several studies support that intranasal oxytocin administration and voluntary wheel running are treatments endowed with anxiolytic properties. Additionally, other studies demonstrated that ECS is crucial for voluntary wheel running performance. For this reason and because the presence of OT and endocannabinoids in the limbic, mesolimbic and endocrine systems has been associated with the anxiolytic response, the purpose of the present study was: (i) to examine whether OT intranasal pretreatment enhances voluntary wheel running behavior and potentiates the anxiolytic properties of exercise in adults male Sprague-Dawley rats, and (ii) to characterize the OTR and CB1R expression within the endocrine regions. Rats were divided in two groups, the first group received intranasal infusions of OT 1 μg /μl, 10 μl or vehicle in each nostril before being exposed to the running wheel two hours daily for 10 consecutive days. The second group received the same dose of OT or vehicle and was not exposed to the running wheel. Results showed that rats treated with OT, exercised more than those treated with vehicle. The results indicated that the rats that received OT exercised more. Using the Light and dark box as a behavioral paradigm, we found that OT potentiated the anxiolytic effect of exercise. Western blots showed that OT treatment significantly increased OT receptors within the pituitary gland of rats exposed to the running wheel. These findings suggest that when both treatments are provided, exercise upregulates OT receptor expression in specific regions related to OT regulation. Future biochemical studies are required to examine the potential cross-talk between OT and the ECS as mediators of the anxiolytic response and exercise performance. We are currently examining OTR’s and CB1R’s expression in other brain regions associated with anxiety-like behaviors to better understand the neurocircuitry underlying the anxiolytic response, and the implications it can have as a treatment for drug addiction, sedentary lifestyle and anxiety disorders.

Presenter: Ingrid De León
Institution: University of Puerto Rico in Cayey
Title: Comparison of potential anxiolytic effect of an organic extract of the brown macroalgae Stypopodium zonale in male and female Drosophila melanogaster using the Dark Light Box Test.
Authors: Liliana A. Pastrana Cruz, Alondra Rosario Valdes, Yaneris M. Alvarado Cartagena,
P.I. Ricardo Chiesa

Abstract: In this study we aim to determine the effects of a Stypopodium zonale crude organic extract that induces anxiolytic-related behavior in female Drosophila melanogaster. Using the Dark/Light Box test as the behavioral assay. We have already reported that a concentration of 1 m/mL of food has anxiolytic effects in Drosophila males. Therefore, we want to assess if hormonal sexual dimorphism is a factor that influences the anxiolytic properties of a crude extract of this brown macroalgae. As happens in other species of invertebrates and vertebrates, the biochemical response to stress differs from male to female due to the hormonal microenvironment. A crude organic extract of Stypopodium zonale will be obtained using a combination of dichloromethane/methanol (1:1) as solvents, and the crude solids will be dissolved in 15% dimethyl sulfoxide (DMSO). The extract will be administered (1 mg/mL, 0.5 mg/mL, and 0.1 mg/mL) to the experimental group in the food since oviposition, while the control group will be fed with regular food. Based on previous results published by our laboratory, we predict an anxiolytic effect of the extract if female flies, though the effective concentration in females may be different.

Presenter: Jaysen Lara-Jiménez
Institution: University of Puerto Rico Rio Piedras
Title: Effect of galactic cosmic radiation and the neuroprotective antioxidant CDDO-EA on the acquisition of stimulus-response and extinction learning in female mice
Authors:Jaysen A. Lara-Jiménez, Frederico C. Kiffer, P.I.  Amelia J. Eisch

Abstract: Effects of galactic cosmic radiation and the neuroprotective antioxidant CDDO-EA on the acquisition of stimulus response and extinction learning in female mice NASA’s aims to send humans to Mars in the 2030s. However, long-term, deep spaceflight as will occur during a Mars mission presents major obstacles, such as exposure to potentially harmful space radiation, or galactic cosmic radiation (GCR), and its high-energy charged particles (Nelson., et al 2016). GCR is composed of 90% protons, 9% He ions, and 1% heavier ions which are referred to as HZE particles. Earth’s radioprotective magnetic field prevents human exposure to space radiation, prompting the need for laboratory animal studies. One issue in the lab animal central nervous system (CNS) space radiation literature is that it is heavily biased towards males. A select percentage of this research area has assessed radiation effects on female CNS endpoints, an important underrepresentation, considering the astronaut population is increasingly sexually diverse. Recent findings suggest the female rodent brain may be less susceptible to radiation-induced immune and cognitive deficits than the male rodent brain, warranting further study of space radiation on mature female mice (Krukowski., et al 2018). Another issue with the literature is that CNS radiation risks have been informed by ‘classical’ open arena-based behavioral tests. Such tests introduce a confound in rodents who, as prey species, are endogenously anxious in open areas. To address this, we exposed female C57BL/6J mice to either Sham irradiation (IRR) or 750mGy of a ground-based, multi-energetic, 33-beam GCR at NASA’s space radiation laboratory in Upton, NY. A subset of mice were also given either control Chow or the countermeasure CDDO-EA, a spaceflight compatible, potent antioxidant (Stack., et al 2010). 9 months post-IRR, mice were assessed for CNS function by performance on two cognitive tasks in an operant touchscreen platform.

Presenter: Jesús Rosario-Claudio
Institution: University of Puerto Rico at Cayey
Title: Association Of White Matter Integrity With Salivary Cortisol Levels And Depression Severity In Women
Authors: Jesús M. Rosario, Claudio Charlene Rivera Bonet, P.I. Dr. Heather Abercrombie

Abstract: Depression is among the most treatable of mental disorders, and almost all patients gain some relief from their symptoms. Unfortunately, approximately 10%-20% of patients don't respond well to present-day treatments or don't respond at all (Parekh, 2017). In this experiment, we will analyze the relationship between depression severity, cortisol levels, and white matter integrity of women with depression and healthy controls. In order to determine depression severity, we will be using the Beck Depression Inventory (BDI). To measure cortisol levels, we will apply a cortisol saliva test. To determine the neural correlates of depression, we will use Diffusion Tensor Imaging (DTI) and Tract-based spatial statistics to measure fractional anisotropy (FA) of the entire brain, using BDI and cortisol levels as continuous variables. We expect that the results showcase a pattern in which we can associate that the higher the severity of the depression, the higher the cortisol levels and as a result, the more FA dysregulation. A greater understanding of the mechanism of depression can, potentially, be used for the development of new treatments and the modification of present-day treatments to help and assist the community of untreatable patients with present-day treatments.

Presenter: Andrea López
Institution: Universidad de Puerto Rico en Arecibo/ NB UPRA
Title: Visual Neuroprosthetic
Authors: Andrea M. López Tomasini; Yahdiel Ayala Arocho
Mentor: Paola Morales Carvajal

Abstract: About 86 million people are blind, sadly the options for these are limited and even more so for people who have suffered from enucleations. That is why our research project is aimed at creating a visual neuroprosthetic for those who have lost the eyeball. Our goal is to help the patient have better and cheaper options when opting for a visual prosthesis. In addition, is to help the patient have better and cheaper options when opting for a visual prosthesis. In addition, that it is not only to cover the affected area, but also that they can take advantage of it and that it makes their daily living a little easier, not only for aesthetic reasons. On the other hand, existing visual neuroprostheses depend on the use of glasses and our team intends to eliminate their use by replacing them with an ocular implant, so that the patient feels that it is more one of his limbs than a garment on which he will depend to see.

Presenter: Andrea N. Rivera Vélez
Institution: Neurobiology Institute
Title: The Use of Open Field Tests as an Assay of Anxiety Behavior in Mice.
Authors: Andrea N. Rivera Vélez
P.I.:  Cristina Velázquez-Marrero, Ph.D.

Abstract: The following presentation proposes that when mice are exposed to Bisphenol A (BPA) injections, we will be able to see profound effects which will cause deficits in their anxiety levels. Since there have been previous reports of BPA effects on cognition, learning and behavior, we first collected preliminary data which shows the effects of BPA on mice in Fear Conditioning Learning paradigms. We saw that BPA showed learning deficits in mice during extinction sessions. Since this paradigm is involved in hippocampal learning and the basolateral amygdala circuits, we concluded that BPA affects these areas. In order to better understand where BPA exerts its effects in the brain, we will compliment these results using the Open Field Tests to further characterize the circuitry involved in BPA effects on anxiety behaviors.

Presenter: Jaseph Soto
Institution: University of Connecticut
Title: Potential roles of KCNQ2 in Respiratory Homeostasis
Authors:Daniel K. Mulkey, PhD, Anastasios Tzingounis, PhD.

Abstract: Potassium channels are critical for normal brain function. In particular, KCNQ2/3 channels have emerged as critical regulators of neonatal brain excitability. A key feature for some patients with KCNQ2 Gain-of-Function variants is chronic hypoventilation, however the mechanisms by which KCNQ2 variants lead to hypoventilation is completely unknown. Currently, the role of KCNQ2 channels in control of breathing is not clear. Although mutations in KCNQ2 are rare, respiratory phenotypes associated with KCNQ2 mutations provide unique insight into the importance of this channel in control of breathing. The present project aims to systematically investigate how loss of KCNQ2 affects respiratory control across multiple levels of the respiratory circuit.

Presenter: Jannay Pacheco Torres
Institution: Pontifical Catholic University of Puerto Rico
Title: Baroreceptor's Role In The Cardiovagal Control In POTS Patients.
Authors: José Criado Del Valle, PhD Marisol Camacho Santiago, PsyD, P.I. Jannay Marie Pacheco Torres

Abstract: Postural Orthostatic Tachycardia Syndrome (POTS) is defined as the presence of chronic symptoms with intolerance of the regulation of blood pressure at a rapid rate accompanied by a high heart rate of 30 beats per minute between the 10 minutes in which the person is in a vertical position. Baroreceptors are the sensors that provide information about the blood flow to the Central Nervous System. The nervous system, through the vagus nerve, regulates cardiac function. The purpose is to describe the role of the baroreceptors in the mechanism of actions of the cardiovagal control in patients with POTS. This study uses data of 90 subjects that include systolic blood pressure, diastolic blood pressure, heart rate (resting - supine position, 1 min tilt, 10 min tilt at 70°), electrocardiogram (EKG), and an evidence of presentation of POTS. All participants performed standardized testing protocol of the Autonomic Reflex Screen used in the Autonomic Laboratory at Scripps Clinic at La Jolla, California. All measurements were obtained while patients were in supine position before HUT, during HUT (at 1 min, 5 min and 10 min of HUT), and at 1 min after patient returned to supine position. Patients were in resting supine position for at least 30 minutes and baseline recordings were obtained for 5 minutes. Respiration rate will be determined by calculating the number of breaths for 1 minute while the patient was in supine position and then after 9 minutes in head-up tilt. Currently, statistical analyses are being done.

NeuroBlitz

Alexaida Mercado and Eduardo Díaz
Title: Designing, Fabrication and Characterization of a Feedback SmartSock Neurobionic Sensor.
Institution: Polytechnic University of Puerto Rico 

Arturo Rivera
Title: PL delays avoidance in high conflict.
Institution: University of Puerto Rico School Rio Piedras  and University of Puerto Rico School of Medicine

Jonathan Morán
Title:Characterizing the role of the prefrontal cortex in timing behavior during approach-avoidance conflict.
Institution:  University of Puerto Rico School Rio Piedras  and University of Puerto Rico School of Medicine

Christian Bravo Rivera
Title: Stimulation of GABAergic neurons in the ventral pallidum promotes risky reward seeking.
Institution:  University of Puerto Rico School of Medicine

Enrique Billoch
Title: Measurement of medium spiny neurons Sodium and Potassium electrical currents and their relationship with alcohol induced Synaptic Plasticity.
Institution: Institute of Neurobiology 

Carolina Dasta-Cruz
Title: The Role of Tip60 in the Development of Alcohol Tolerance.
Institution: University of Puerto Rico at Rio Piedras

Jadier Colon Vazquez
Title: Amyloid-beta (Aβ) oligomeric aggregation in glaucoma.
Institution: Universidad Central de Caribe

Alberto Díaz de Jesus
Title: Changes in Gene Expression in Response to Alcohol Exposure Mediating Molecular Alcohol Tolerance.
Institution: Institute of Neurobiology

Jessalyn Pla-Tenorio
Title: Feasibility of lentiviral vector expressing HIV-1 Nef in astrocytes.
Institution: Ponce Health Sciences University

28TH PUERTO RICO
NEUROSCIENCE CONFERENCE
Institute of Neurobiology
© Copyright 2020 - Puerto Rico Neuroscience - All Rights Reserved
Institute of Neurobiology
Attn: Dr. Cristina Velazquez-Marrero
201 Blvd del Valle
San Juan, PR 00901
Phone: 787-721-4149 Ext. 237
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