bluuebunny/crossref_metadata_2025_split huggingface dataset:
Autophagy Induction Via κ‐Opioid Receptor is Implicated in Stress‐Driven Synaptic Alterations
Authors: Georgoussi Zafiroula , Karoussiotis Christos , Sotiriou Aggeliki , Polissidis Alexia V. , Papavranoussi‐Daponte Danae , Symeonof Alexandra , Nikoletopoulou Vassiliki 
Published: May 2022

Neuronal autophagy controls the quality of cytoplasmic proteins through degradation of important synaptic proteins and modulates synaptic organization and morphogenesis (1). Evidence has shown that G protein coupled receptors are direct sensors regulating the autophagic machinery (2) and opioid receptors regulate neuronal plasticity and neurotransmission with as yet unclarified mechanism (3,4). Using in vitro and in vivo studies, we demonstrated that κ‐opioid receptor (κ‐OR) agonists induce autophagy via a PTX‐sensitive G protein manner and identified the downstream components involved (5). Our molecular analysis also revealed a κ‐OR‐driven upregulation of becn1 gene through ERK1,2‐dependent activation of the transcription factor CREB in neuronal cells. Moreover, our studies demonstrated that sub‐chronic U50,488H administration in mice causes profound increases of specific autophagic markers exclusively in the hippocampus with a concomitant decrease of several pre‐ and post‐synaptic proteins such as spinophilin, PSD‐95 and SNAP25. Finally, using acute stress, a stimulus known to increase the levels of the endogenous κ‐OR ligand dynorphin, we are demonstrating that administration of the κ‐ΟR selective antagonist, nor‐binaltorhimine, blocks the induction of autophagy and the stress‐evoked reduction of synaptic proteins in the hippocampus. These findings provide novel insights about the essential role of autophagic machinery into the mechanisms through which κ‐OR and its signaling regulates brain plasticity.References1. Nikoletopoulou V, Papandreou ME, Tavernarakis N (2015) Cell Death Differ 22: 398‐4072. Wauson EM, Dbouk HA, Ghosh AB, Cobb MH (2014) Trends Endocrinol Metab 25: 274‐2823.3. Georganta EM, Tsoutsi L, Gaitanou M, Georgoussi Z (2013) J Neurochem 127: 329‐3414. Kibaly C, Xu C, Cahill CM, Evans CJ, Law PY (2019) Nat Rev Neurosci 20: 5‐185. Georgoussi Z and Karoussiotis C (2019) FASEB J. Supplement Issue Vol.33
Transitioning from In Person to Online Human Anatomy: Student Perspectives from the COVID‐19 Pandemic
Authors: Kaufman Rachel E. , Patel Kush , Edmondson Anna 
Published: May 2022

Introduction & ObjectiveIn March 2020, medical schools around the country had to quickly transition from in person cadaveric anatomy curricula to an online distance learning format due to the COVID‐19 pandemic. This posed a challenge for students who had acclimated to learning anatomy inside the laboratory for the majority of their first year of medical school. The purpose of this study was to assess student perceptions of the abrupt transition from in person anatomy dissections and practical exams to an exclusively online format.Materials and MethodsAn anonymous survey was distributed to medical students from the Class of 2023 at the Medical College of Georgia at Augusta University (n=191) in February 2021. The survey assessed student perceptions of the impact of COVID‐19 shutdowns on their medical education. In total, 45 responses were recorded, and survey data was analyzed using SPSS software. Nonparametric methods were used due to the ordinal nature of the Likert scale responses. A Wilcoxon signed rank test was performed. In addition, focus groups were conducted with 11 medical students who had completed the survey.ResultsA majority of respondents (82.55%) stated that their learning and understanding of anatomy was worse after cancellation of in person anatomy lab dissections. In contrast, understanding of didactic lecture material was split, with 37.5% stating that online lectures had no impact on their learning and understanding of the material, 31.25% stating understanding was worse, and 25% stating it was better following transition to online‐only lectures. The results from the Wilcoxon signed rank test of Likert scale responses indicated that students perceived impact of cancelling in person anatomy lab as significantly worse compared to the impact of cancelling in person lectures (p<0.001). Focus group responses echoed this theme, with the loss of 3‐dimensional visual and tactile learning in laboratory cited most frequently by participants as a challenge with the transition to online anatomy.ConclusionMedical student respondents in the class of 2023 perceived online anatomy as inferior to in person laboratory sessions after the COVID‐19 shut‐down in March 2020. The transition from in person to online anatomy was more impactful on student understanding of material than the transition from in person to online didactic lectures. Of note, the students surveyed had completed the majority of their anatomy curriculum in person prior to the transition online.Significance/ImplicationThe medical school shutdowns that occurred in March 2020 due to the COVID‐19 pandemic highlighted the importance of in person interaction with cadaveric specimens in anatomy education, especially in the context of how students were initially exposed to content. When possible, consideration should be given to learning approaches that students are familiar with and how changes to the curriculum will impact them.
Caffeine Induces Spontaneous Ventricular Tachyarrhythmias and Bidirectional Ventricular Tachycardia: Increased Vulnerability with Aging
Authors: Chen Victor , Choudhury Nibras , Zhang Youhua 
Published: May 2022

IntroductionCaffeine is generally suspected to trigger or exacerbate cardiac arrhythmias in patients, but so far clinical data have been conflicting. We have demonstrated previously that caffeine plus dobutamine challenge can induce ventricular tachyarrhythmias in normal rats (Heart Rhythm O2 2020;1:359‐367). However, whether caffeine alone can induce cardiac arrhythmias has not been investigated. We hypothesize that caffeine alone could trigger spontaneous cardiac arrhythmias, which may be affected by aging and sexes. In this study we have investigated the effect of caffeine on spontaneous cardiac arrhythmias in younger and older adult rats of both sexes.MethodsThis study used Sprague‐Dawley rats. Younger (5‐month‐old) and older (1‐year‐old) adult rats of both sexes were enrolled. The study consisted of the following groups: 5‐month‐old male rats (younger male, n=8) and 1‐year‐old male rats (older male, n=9), 5‐month‐old female rats (younger female, n=6) and 1‐year‐old female rats (older female, n=5). These rats received caffeine (80mg/kg, IP) injection. In addition, a group of 5‐month‐old rats (both sexes, n=8) receiving saline injection without caffeine served as the control group. Surface electrocardiogram (ECG, standard Lead II) was continuously monitored and recorded during the experiments.ResultsNo arrhythmia was induced in the control group with saline injection. Caffeine injection induced ventricular tachyarrhythmias in 8/9 older male rats, while only in 2/8 younger male rats (younger versus older male rats, p=0.0152, Fisher's exact test). Similarly, ventricular arrhythmias were induced in 5/5 older female rats, and only in 1/6 younger female rats (older versus younger female rats, p=0.0152). There were no significant differences in male versus female rats in both age groups. Induced ventricular arrhythmias include various premature ventricular contractions (PVC, Figure‐Panel A) in all rats, monomorphic ventricular tachycardia (VT, Panel B) in 3 rats and polymorphic VT and bidirectional VT (Panel C) in all rats. No atrial arrhythmia was observed.ConclusionCaffeine can induce spontaneous ventricular arrhythmias in normal rats, and the younger rats are more resistant to arrhythmia induction. Arrhythmia inducibility increases significantly in older rats. There is no sex difference in caffeine induced ventricular arrhythmias. Although different types of ventricular arrhythmias are induced, the characteristic bidirectional VT is highly prevalent among the caffeine induced arrhythmias and no atrial arrhythmia was observed.
Selective mGlu1 Potentiation Reverses Cortical Disinhibition and Schizophrenia‐like Social and Cognitive Deficits
Authors: Gallinger Isabel G. , Luessen Deborah , Conn Jeffrey 
Published: May 2022

There is a critical need to develop novel therapeutic strategies for addressing the negative and cognitive symptom domains in schizophrenia (SCZ). Multiple clinical and preclinical studies support the hypothesis that loss of GABAergic inhibitory transmission in the prefrontal cortex (PFC) and other forebrain regions may play a critical role in the pathophysiological changes underlying cognitive and social behavioral deficits in SCZ patients. Recently, we demonstrated that activation of the mGlu1 subtype of metabotropic glutamate receptor increases inhibitory transmission in the PFC by selective excitation of somatostatin‐expressing GABA interneurons. Genetic studies in humans reveal an association between deleterious non‐synonymous single nucleotide polymorphisms (nsSNPS) in of the human gene encoding mGlu1 (GRM1) and SCZ, raising the possibility that mGlu1 signaling is critical to the function of brain circuits underlying symptoms associated with this disorder.Here, we examine whether novel positive allosteric modulators (PAMs) selective for mGlu1 reverse electrophysiological effects and behavioral deficits in an MK‐801‐induced animal model of SCZ. We used ex vivo whole‐cell patch‐clamp electrophysiology to show that MK‐801 decreased the frequency of spontaneous inhibitory postsynaptic currents onto layer V pyramidal cells of the PFC, and this cortical disinhibition was reversed by mGlu1 activation. Furthermore, acute MK‐801 treatment induces inhibitory deficits onto PFC‐basolateral amygdala (BLA), but not PFC‐nucleus accumbens, projecting layer V pyramidal cells that can be reversed by selective mGlu1 activation. PFC‐BLA projections are known to contribute functionally to social‐approach behavior, while the BLA plays a critical role in object recognition and cognition broadly. We found that the mGlu1 PAM VU6004909 effectively reversed MK801‐induced deficits in social interaction and social novelty preference in a three‐chamber assay. Additionally, VU6004909 restored novel object recognition following MK‐801 treatment. In combination with our previous reports that mGlu1 PAMs reverse deficits in inhibitory transmission in the PFC, the current study provides strong evidence for mGlu1 PAMs as a promising novel approach for the treatment of social and cognitive deficits in SCZ patients.
Using Google Tools to Increase Student Learning, Engagement, and Collaboration in Remote, Hybrid, and In‐person Courses
Authors: Stokes Jennifer A. 
Published: May 2022

The COVID‐19 global pandemic turned the educational community upside‐down. As all in person coursework quickly transitioned to online delivery, faculty had to formulate new ways to not only disseminate course content but also assess student learning and engage students in the virtual classroom. As the pandemic state continues to affect higher education, the use of online collaborative tools has become essential to many college classrooms. This poster reviews the implementation of a selection of Google tools (e.g. Docs, Forms, Jamboard) in remote, hybrid, and in‐person courses.Initially, these online tools were added to engage students when strict COVID‐19 guidelines were in place in the hybrid and remote classroom setting as a way to promote student collaboration and group learning. In class activities, homework, and other group assignments were modified such that both in‐person and remote students could collaborate in real time during the synchronous class session and outside of scheduled class time. Student feedback on course evaluations indicate that the learning environment was positive, collaborative, and engaging. Student comments specifically pointed to the success of these activities. Students ranked the course greater than 4.0 (out of 5.0) across all evaluative questions.In the spring 2020 hybrid version of the course, summative assessments were modified to include open‐book take‐home case studies in addition to the timed objective exam. Required biweekly virtual small group sessions allowed students to collaborate on these challenging case‐based critical thinking problems. The case study exams were designed in Google Docs and a template file (copy function) was created for student use. Overall student perception of the case study exams was very high as indicated by the students' ranking of this activity on a survey and written feedback. Additionally, student performance improved on the case study exams (p < 0.001) as their critical thinking, analytical, and scientific writing skills improved, while their performance on the timed objective exams remained relatively consistent (p = 0.157).Examples of how these online tools can be set‐up for use as formative and summative assessments as well as interactive, collaborative activities will be presented and shared using QR codes at the poster session. As coursework has returned to in‐person learning, many of these tools are still used due to ease of use, positive feedback, and benefits to student learning.
Mapping myocyte microdomains with optogenetic cAMP signaling
Authors: Haar Lauren , Kinney William , Lawrence David 
Published: May 2022

Recent advances in biosensor and optically based techniques have provided a map of the subcellular regions that dictate myocyte behavior. Microdomain level changes of cyclic adenosine 3’5’ monophosphate (cAMP) signaling are known to impact the progression of cardiovascular disease. Yet, tools to direct these site‐specific interactions are limited. To address this issue, we have applied a set of optogenetic protein species with the spatiotemporal resolution necessary to direct cAMP signaling at distinct intracellular sites. We hypothesize that applying these proteins to a cardiac cell system will help resolve the relationship between cAMP microdomain signaling and cardiac cell behavior.Photoactivation studies have been conducted using optogenetic analogues of adenylate cyclase and protein kinase A (PKA) in the H9c2 cell model. Expression and subcellular localization of these light responsive proteins is characterized by live cell microscopy in this cardiac cell line. Site‐specific impacts of signaling are quantified using a genetically encoded PKA activity biosensor as well as pharmacological agonists/antagonists for cAMP signaling mediators and effectors.Results indicate that global cAMP production, through a light activatable adenylate cyclase (bPAC), leads to phosphorylation of a PKA reporter anchored at the outer mitochondrial membrane and plasma membrane. Reporters with nuclear localization do not show this phosphorylation. Experiments validate the expression and recruitment of a light directed protein kinase A ‘optogenetic switch’ analog in cardiac cells. The expression and recruitment are confirmed with live cell microscopy and demonstrate a unique ability to direct PKA activity and retention to specific intracellular subdomains. The impact of this signaling on microdomain organization as well as the site‐specific impacts of light directed PKA microdomain recruitment on cell proliferation, size as a function of biomass, and cell viability compared are considered. This is done in relationship to non illuminated (dark) and catalytically dead optogenetic protein analog controls.We conclude from these results that light directed signaling in cardiac myocytes can provide a site‐specific view of intracellular signaling cascades. The application of this approach represents a ‘first step’ in creating therapies that address the microdomain signaling disruptions associated with cardiac disease.
Inhibition of SUMO‐mediated Protein‐Protein Interactions in DNA Damage Repair
Authors: Jones Emily E. , Thu Yee Mon 
Published: May 2022

Maintenance of genomic integrity requires functional repair mechanisms. Some mechanisms include the use of sumoylation, a process in which proteins are post‐translationally modified with a small peptide SUMO (small ubiquitin‐like modifier). In response to DNA damage, multiple proteins become sumoylated. Current evidence suggests that sumoylation in this context mediates protein‐protein interactions to promote DNA damage repair. SUMO‐interacting motifs (SIMs) play an essential role in SUMO‐mediated protein‐protein interactions. The SIM on a protein is a region that allows it to recognize and bind the SUMO attached to another protein. Previous studies have shown that inhibiting this type of interaction can lead to sensitized cancer cells by impairing DNA damage repair and response. Thus, this project aims to study a similar inhibition by overexpressing SIMs naturally found in two proteins, Slx5 and Sgs1, in the eukaryotic model organism, Saccharomyces cerevisiae. Both proteins are a part of their respective protein complexes, and their SIMs serve as a functional way for the complexes to interact with sumoylated proteins during DNA repair. We hypothesize that overexpressed SIMs will disrupt endogenous SUMO‐SIM interactions important for DNA damage repair and that cells with overexpression of the SIM would be sensitized to DNA damaging agents. We observed that cells overexpressing SIMs from Slx5 exhibited a growth defect compared to cells without overexpression. However, when treated with DNA damaging agents, such as methyl methanesulfonate and UV, cells with SIM overexpression exhibited little to no sensitivity compared to the wild type.To further explore the effect of SUMO‐SIM interaction, we have designed another protein containing the DNA‐binding (SAP) domain of Siz2, a SUMO protein ligase specific to DNA damage, and the SUMO‐binding domain of Ulp1, a SUMO isopeptidase, to potentially disrupt SUMO:SIM interactions involved in DNA repair. Inclusion of the SAP domain along with a nuclear localization signal (NLS) is hypothesized to increase the nuclear localization of the protein during DNA repair, which will be observed using fluorescent microscopy of a GFP tag incorporated into the protein. With increased nuclear localization and inclusion of the SUMO‐binding domain, we hypothesize that there will be disruption to the SUMO:SIM interactions involved in DNA damage repair, resulting in an increase in the cells’ sensitivity to DNA damaging agents.
Deletion of Myostatin Resolves Myosteatosis and Improves Angiogenesis in Obese Mice
Authors: Speese Andrew , Padgett Caleb , Bridgewater Cody , Mintz James , Corley Zachary , Fulton David , Stepp David 
Published: May 2022

Andrew C. Speese, B.S.1, Caleb A. Padgett M.S.1, Cody L. Rosewater M.S.1, Zachary L. Corley B.S.1, James D. Mintz M.B.A.1, David J. Fulton Ph.D.1,2, and David W. Stepp Ph.D.1,31Vascular Biology Center, 2Department of Pharmacology and Toxicology, and 3Department of Physiology, Medical College of Georgia, Augusta University, Augusta, GAObjectiveTo test the hypothesis that increased muscle mass achieved through deletion of myostatin improves ischemic angiogenesis in obese mice.Methodsdb/db mice, a well‐described model of obesity, were crossed with mice lacking myostatin (MSTN KO), a myokine that negatively regulates muscle differentiation and growth, to generate lean and obese mice with and without elevated muscle mass (MSTN KO). We utilized confocal and electron microscopy (EM) and nuclear magnetic resonance (NMR) spectroscopy to assess morphology and histology in the skeletal muscle (SKM) of db +/‐_MSTN +/‐ mice. Muscle lipid contents were assessed via mass spectrometry. Femoral artery ligation was used to stimulate in vivo angiogenesis in response to ischemia. Gene expression was assessed by RNA‐Seq with mRNA and protein expression follow‐up in isolated gastrocnemius skeletal muscle via RT‐qPCR and western blotting.ResultsAs previously described, myostatin deletion results in significantly increased muscle mass without altering whole‐body mass, fat percentage, or activity levels in obese db/db mice. Blood glucose is markedly improved but plasma lipids remain elevated. In parallel with these improvements, we observed that obesity inhibits and MSTN deletion restores vascularization following hind limb ischemia. Despite persistent plasma lipedema, ectopic lipid deposition in skeletal muscle was largely ameliorated in obese mice lacking myostatin, a reduction largely explained by a decrease in tissue triglyceride levels. EM and confocal microscopy revealed accumulation of lipid in obese muscle cells that was lacking in obese mice with MSTN KO. The resolved deposition occurred predominantly inside muscle cells with fat cell infiltration in external spaces largely unaffected. RNA‐Seq analysis of skeletal muscle revealed marked upregulation of lipogenesis pathways, notably the expression of stearoyl Co‐A desaturase 1 (SCD1), the rate limiting enzyme for the oleate synthesis and subsequent triglyceride production. SCD1 was elevated in muscle from normal obese mice but not those lacking myostatin at both the protein and RNA level.ConclusionIn summary, increased muscle mass in obese mice provides potent protection to vascular and metabolic health. A potent correlate of this improvement is the resolution of myosteatosis in obese, hypermuscular mice. These data suggest that resolution of myosteatosis, independent of muscle mass, may afford similar protection, possibly by targeted deletion or blockade of SCD1.