bluuebunny/crossref_metadata_2025_split huggingface dataset:
G Protein‐coupled Estrogen Receptor Protects Against Aging‐Induced Vascular Dysfunction in Females but Not Males.
Authors: Zimmerman Margaret , Ogola Benard , Lindsey Sarah 
Published: April 2020

G protein‐coupled estrogen receptor (GPER) promotes the vasoprotective effects of estrogen, and we previously published that resistance vessels from middle‐aged female rodents are less responsive to selective GPER activation compared with adult vessels. Therefore, we hypothesized that aging or global GPER deletion would induce similar dysfunction in the vasculature. Mesenteric resistance arteries were isolated from adult (21–25 weeks old) and middle‐aged (52–57 weeks old) male and female wildtype (WT) and GPER knockout (KO) mice. Vessel reactivity was measured via wire myography in response to increasing doses of vasoconstrictors phenylephrine (PE) and prostaglandin F2α (PGF2α) and vasodilators acetylcholine (Ach) and sodium nitroprusside (SNP). PGF2α‐induced constriction was significantly decreased with aging in WT males (446 ± 15% vs. 378 ± 14%; P=0.02) but not in vessels from KO males (434 ± 24% vs. 416 ± 30%; ns). PE‐induced constriction was comparable between male middle‐aged and adult WT (401 ± 19% vs. 416 ± 22%; ns) and KO vessels (416 ± 22% vs. 398 ± 19%; ns). Relaxation to SNP in male animals was comparable between age groups and unaltered by GPER deletion (WT Middle‐Aged: 26 ± 6% vs. Adult: 15 ± 4%; ns; KO Middle‐Aged: 14 ± 3% vs. Adult: 11 ± 2%; ns). However, GPER deletion enhanced relaxation to Ach in middle‐aged males (WT: 42 ± 7% vs. KO: 18 ± 5%; P<0.01) but not adult males (WT: 37 ± 9% vs. KO: 28 ± 12%; ns). In females, PGF2α‐induced vasoconstriction was significantly greater in middle‐aged versus adult WT vessels (446 ± 18% vs. 388 ± 32%; ns) and abolished with GPER deletion (463 ± 12% vs. 413 ± 25%; ns). PE‐induced constriction was comparable between female middle‐aged and adult WT vessels (454 ± 17% vs. 387 ± 18%; ns) and unaltered by GPER deletion (474 ± 25% vs. 412 ± 26%; ns). In females, relaxation to SNP was not altered by aging or GPER deletion (WT Middle‐Aged: 8 ± 1% vs. Adult: 11 ± 3%; ns; KO Middle‐Aged: 13 ± 3% vs. Adult: 20 ± 6%; ns). However, relaxation to Ach was impaired by GPER deletion in adult female vessels (WT: 7 ± 1% vs. KO: 26 ± 10%; P=0.01) but not in middle‐aged vessels (WT: 6 ± 1% vs. KO: 20 ± 5%; ns). The current study demonstrates that the role of GPER in resistance artery function is dependent on sex and age. In males, GPER deletion enhanced vasoconstriction in adult animals but improved endothelial‐dependent vasodilation in middle‐age. In females, GPER deletion was detrimental for endothelial function in adulthood and enhanced vasoconstriction in middle‐age. Therefore, GPER function may contribute to vascular protection in aging women but not men.Support or Funding InformationThis study was funded by NIH grants HL133619 and U54 GM104940.
Identification of potential agonist of human and mouse FFAR2 by homology modeling and molecular docking study approach
Authors: Karunakar Prashantha , Mishra Sidharth P. , Razazan Atefeh P. , Sharma Shailesh , Yadav Hariom 
Published: April 2020

The contribution of gut microbiome and its metabolites like short chain fatty acids (SCFAs; such as acetate, propionate, butyrate) became apparent to impact human health. SCFAs not only feed the intestinal cells, but also function as gut microbiome sensors on distinct cell types through activating G‐couple protein receptors like free fatty acid receptor 2 and 3 (FFAR2&3). FFAR2 is widely expressed in intestine, immune cells, adipose tissues, pancreas and others, and plays important role in several human diseases like diabetes, obesity and immune disorders. FFAR2 plays an important role in the regulation of homeostasis and in the intestine immunity. SCFAs are strong agonists of FFAR2, but they are often found decreased in the gut of diseased host, therefore, developing agonists that can enhance FFAR2 activity could of therapeutic importance of several human diseases. In the present study, we screened 125,000 natural compound library with human FFAR2 docking patterns, and selected 14 compounds. These selected compounds were further docked with the homology modeled human and mouse FFAR2 to identify the potential agonist and antagonist using molecular docking approach. The interaction of the ligands with the key residues of human FFAR2 namely His242, Arg180 and Arg255 found to be the determining molecules to identify the agonist and antagonist nature of molecules. Using AutoDock Vina and hydrogen bonding scores, ZINC00388198 showed a potential agonist probability against human FFAR2 and mouse FFAR2. Compound ZINC00968099 and ZINC00403588 showed a potential antagonist probability against human FFAR2 and mouse FFAR2, respectively. Further studies are underway to will demonstrate the direct activation of FFAR2 signaling in cell culture and mouse models of selected molecules, and their biological functions such as anti‐aging and anti‐diabetic effects in C. elegans and mice. Results of these studies will uncover novel natural compounds that can activate FFAR2 to exhibit beneficial functions against several human diseases, associated with microbiota dysbiosis and decreased SCFAs levels.Support or Funding InformationWe thank for the Department of Defense, the National Institutes of Health and resources from Wake Forest School of Medicine.
Insights into the mechanisms of inflammatory acidification within the mucosa
Authors: Cartwright Ian Michael , Lanis Jordi M. , Alexeev Erica E. , Schaefer Rachael E.M. , Welch Nichole , Kostelecky Rachael , Gao Rachel , Onyiah Joseph C. , Colgan Sean P. 
Published: April 2020

Tissue acidification is commonly associated with a number of inflammatory states. The primary mechanism of extracellular acidification is thought to be increased accumulation of lactic acid resulting from enhanced glycolysis. Like other chronic inflammatory diseases, tissue acidification has been observed in inflammatory bowel disease patients, with reports of colonic pH as low as 4. We have recently demonstrated that neutrophil (PMN) transepithelial migration rapidly acidifies the microenvironment resulting in inflammatory acidification in the mucosa. Very little is known with regard to the mechanism(s) involved in this acidification or the impact of such acidification on the intestinal epithelial cell (IEC) function. Initial observations showed that physical interaction between IEC and PMN was required for inflammatory acidification; however, when transmigration was blocked using anti‐CD11b antibodies, we observed significant extracellular acidification in the absence of PMN transepithelial migration. This observation suggests that binding of the CD11b receptor plays a crucial role promoting extracellular acidification. Expanding upon these observations, we analyzed extracellular lactate secretion. We observed that lactic acid was released by IEC 4 to 5 hours after the addition of PMN and in quantities not high enough to account for the extracellular acidification observed. Additionally, the concentration of lactic acid released in the anti‐CD11b treated cells was similar to control IEC in the absence of PMN. When combined, these data indicate lactate is not a significant mediator of extracellular acidification following PMN transmigration. Given the large number of PMNs present and chronic tissue acidification observed during active inflammation, we investigated the impact of extracellular acidification on the regulation of epithelial derived pro‐inflammatory markers. When T84 IEC were cultured in pH 6.0 media for 3 or 6 hours we observed increases in pro‐inflammatory markers, including IL‐8. To better understand how extracellular acidification alters IEC gene regulation, we utilized a transcription factor array to examine changes in transcription factor expression under acidic conditions. This screen identified CREB as one of the major transcription factors controlling responses to acidification. Further examination revealed that CREB phosphorylation occurs rapidly, is cAMP independent, and requires MSK1. Inhibition of MSK1 prevents the induction of IL‐8 and other acidification associated gene transcription. Theses result identified extracellular acidification as a significant signaling mechanism during tissue inflammation. Targeted regulation of MSK1 may serve as a new therapeutic approach to limit pro‐inflammatory signaling during mucosal inflammation.Support or Funding InformationR01 DK095491, NIH
The Roles of Essential Proteins Prp6 and Dib1 During Pre‐mRNA Splicing in Saccharomyces cerevisiae
Authors: Embry Addie , Jameson Danielle , Turner Caitlyn , Maeder Corina 
Published: April 2020

Pre‐mRNA splicing is a conserved biological process essential to all eukaryotes. Splicing defects lead to a variety of disorders in humans including Retinitis Pigmentosa and Burn‐McKeown Syndrome, defining the importance of splicing in health science fields. Pre‐mRNA splicing requires complex machinery composed of five small nuclear RNAs (snRNAs) complexed with numerous proteins that form five small nuclear ribonucleoproteins (snRNPs). Spliceosome assembly occurs over several dynamic steps to form a pre‐catalytic B complex before splicing reactions can occur (Will, et al. 2011; Plaschka, et al. 2017).Splicing cannot occur until the pre‐mRNA can interact with the Prp8 protein and the U5 snRNA in the catalytic center of the spliceosome. Analysis of cryo‐EM structures reveal that the essential proteins Dib1 and Prp6 in the B complex block pre‐mRNA from interaction with the catalytic site. Dib1, a 17‐kDa protein with a thioredoxin‐like (TRXL) domain, sits at the center of the catalytic site (Plaschka, et al. 2017). Although small, Dib1 contains distinct features that includes a solvent‐exposed hydrophobic groove which appears to interact with the N‐terminus of Prp6, a large, 102‐kDa U4/U6.U5 triple‐snRNP protein (Reuter, et al. 1999; Plaschka et al. 2017). Studies of S. pombe and human splicing proteins demonstrated interactions between Prp6 and Dib1 orthologs, and deletion of at least the first 50 amino acids of the Prp6 N‐terminal region halted pre‐mRNA splicing in S. pombe (Liu, et al. 2006; Lutzelberger, et al. 2010).Prp6 and Dib1 must depart the spliceosome before splicing can occur. The interactions between these proteins and the catalytic site of the B complex may serve to stabilize the spliceosome and prevent premature pre‐mRNA splicing. Interactions between Prp6 and Dib1 may also mediate assembly of the spliceosomal B complex. We previously reported that a temperature‐sensitive (ts) mutation in the Dib1 hydrophobic pocket impaired pre‐mRNA splicing, and preliminary assembly assays run on native polyacrylamide gels suggest the Dib1 mutation affects spliceosome assembly. Additionally, we reported that a N‐terminal deletion of Prp6 also halted splicing. Here, we will report new (ts) growth mutants in the N‐terminus of Prp6 that may interact with the Dib1 hydrophobic groove and determine if they inhibit splicing. We will also report continued studies of the effects of existing Prp6 and Dib1 mutants and how they affect splicing and spliceosome B complex assembly.Support or Funding InformationNIH‐NIGMS R15GM120720 and The Welch Foundation
Identification of Patent Foramen Ovale Channel Related Morphometric Features Increasing the Risk of Cerebrovascular Accidents: a Systematic Review and Meta‐analysis
Authors: Holda Jakub Piotr 
Published: April 2020

IntroductionIt is still disputable whether specific morphometric features of the patent foramen ovale (PFO) channel may stratify patients by the related probability that a discovered PFO is incidental or stroke related. Thus, we aimed to determine this using a meta‐analytical approach.Materials and MethodsWe performed a systematic review of electronic databases for studies that compared morphometric parameters of PFO channel assessed by transesophageal echocardiography in subjects with cryptogenic cerebrovascular accidents (Group 1) and control (Group 2). Data were extracted and pooled into a meta‐analysis.ResultsA total of 895 patients with PFO channel were reported (Group 1: 493, Group 2: 402). No difference was found in the PFO channel length (Group 1: 10.8 [8.6–12.9] mm vs. Group 2: 10.4 [9.1–11.7] mm), as well as in PFO height measured at rest (Group 1: 2.4 [1.5–3.3] mm vs. Group 2: 1.8 [1.4–2.2] mm). The PFO height measured during Valsalva was larger in Group 1 (3.5 [2.8–4.1] mm) than in Group 2 (1.7 [1.2–2.2] mm). Also, the septal excursion distance was larger in Group 1 (6.4 [5.1–7.8] mm) than in Group 2 (3.1 [1.8–4.4] mm). The risk of cerebrovascular accident was higher in patients with PFO and concomitant septal aneurysm (OR=4.00; 95%CI: 2.63–6.09; p<0.001) and large right‐to‐left shunt PFO (more than 20 microbubbles) (OR=3.81; 95%CI: 2.21–6.55; p<0.001).ConclusionsLarger PFO height during Valsalva, larger septal excursion distance, concomitant atrial septal aneurysm and large right‐to‐left shunt are stroke high‐risk echocardiographic features of the PFO channel.
Neuroprotective Effects of N,N′bis‐(2‐mercaptoethyl) Isophthalamide (NBMI) Against Lead Induced Toxicity in U‐87 MG Cells
Authors: Gadde Rajitha , Betharia Swati 
Published: April 2020

Background and ObjectiveLead is one of the most dangerous and ubiquitous environmental toxins with no levels safe for human exposure. Lead causes neurotoxicity primarily by inducing oxidative stress. After crossing the blood brain barrier, lead is taken up by glial cells which serve as protective lead‐binding proteins. While chelation is the mainstay of therapy for lead poisoning, currently FDA approved chelators such as dimercaptosuccinic acid (DMSA) are associated with many adverse effects and safety concerns. N,N′bis‐(2‐mercaptoethyl) isophthalamide (NBMI) is a newer lipophilic water insoluble compound with potential metal chelating and antioxidant properties. The purpose of this study was to determine whether NBMI displayed neuroprotective effects in U‐87 malignant glioblastoma (U‐87 MG) cells exposed to lead acetate (PbAc).Materials and MethodsU‐87 MG cells were treated with either vehicle, NBMI (0–100 μM), or DMSA (0–100 μM) for 24 hours followed by PbAc (0–300 μM) for 48 hours. Cell viability (CellTiter‐Glo® Assay), cell morphology (trypan blue staining), degree of oxidative stress (GSH‐GloTM Glutathione Assay), and impact on apoptosis (Bax and Bcl‐2 protein levels using Western blotting) were determined. Comparisons between multiple groups were performed using one‐way or two‐way analysis of variance (ANOVA) followed by a post‐hoc Tukey’s test. Results with a p value <0.05 were considered statistically significant.ResultsExposure of U‐87 MG cells to PbAc decreased cell viability in both a concentration and time‐dependent manner. Trypan blue staining revealed that PbAc negatively altered the cell morphology. In addition, PbAc exposure led to an increase in total glutathione levels, as well as the Bax/Bcl‐2 ratio, indicating increased oxidative stress and initiation of the cell apoptotic pathway. Pretreatment with NBMI diminished PbAc‐induced cell death, morphology changes, increase in total GSH, and increase in the Bax/Bcl‐2 ratio. Interestingly, the effects of NBMI were more prominent compared to DMSA in attenuating PbAc‐induced cell death.ConclusionLead exposure induces cell death and oxidative stress which are reversed by pretreatment with NBMI implying that NBMI is a new and promising chelator for treating PbAc‐induced neurotoxicity.
Predator scent stress induces anxiety and sensitizes the angiotensin II‐elicited hypertensive response
Authors: Xue Jiarui , Beltz Terry G. , Xue Baojian , Johnson Alan Kim 
Published: April 2020

Post‐traumatic stress disorder (PTSD) is associated with increased risk of cardiovascular diseases. In the present study, we examined the cardiovascular, biochemical and behavioral consequences of exposing animals to a predatory scent paradigm. After exposures, we measured factors associated with stress responses in a standardized behavioral test. We also determined the hypertensive response to angiotensin (ANG) II and expression levels of the renin‐angiotensin system (RAS) and proinflammatory cytokines (PICs) in the lamina terminalis (LT), paraventricular nucleus (PVN) and amygdala (Amy). Rats (male Sprague‐Dawley) were placed in a plastic‐shoebox cage and exposed to coyote urine in three 20‐minute sessions on alternating days (stressed). A second group served as home‐cage controls. Three days after the last exposure, three separate cohorts of animals following an identical experimental protocol were studied for 1) sensitization of the hypertensive response, 2) performance in the elevated “plus” maze in order to assess anxiety and 3) changes in expression of mRNA for components of the RAS and markers of inflammation in the LT, PVN and Amy. Stressed rats, compared to the controls, had a significantly greater hypertensive response when challenged with a slow‐pressor dose of ANG II (sensitization), exhibited a significant preference to the closed arms as well as general immobility (i.e. enhanced anxiety) and an upregulated expression of several components of the RAS and PICs in the LT, PVN and amygdala. The results suggest that the predatory scent paradigm, a model for PTSD, sensitizes ANG II‐induced hypertension and induces behavioral signs of anxiety in rats, probably through upregulation of RAS and PICs components in key brain areas associated with fear and the central sympathetic control of blood pressure.Support or Funding InformationNIH HL139575
Enteric Glia Contribute to Visceral Hypersensitivity Through Interactions with Nociceptors
Authors: Morales-Soto Wilmarie , Gulbransen Brian D. 
Published: April 2020

Enteric glia regulate gut motility, secretions, and neuroinflammation through intercellular signaling mechanisms that involve connexin‐43 (Cx43) hemichannels. Glial Cx43 signaling is active during the acute phase of colitis when the sensitization of nociceptors occurs, but how glia contribute to nociceptor sensitization is not known. Here, we tested the hypothesis that alterations to intercellular signaling between glia and nociceptors mediated by Cx43 contribute to the sensitization of nociceptors during gut inflammation. We used the dinitrobenzene sulfonic acid (DNBS) model of acute colitis and tested the effects on enteric glia using immunohistochemistry, multiplex immunoassays, and ethidium bromide dye uptake to measure glial Cx43 channel activity. Specific interactions between glia and nociceptors were assessed using the glial specific GFAP::hM3Dq DREADD mouse model in combination with visceromotor reflex recordings and pERK expression, and by directly recording nociceptor nerve fiber activity in TRPV1‐GCaMP5g‐tdT mice. DNBS colitis drove an increase in proinflammatory cytokines including IL6, TNFα, and IL17, and IL1β showed a 5‐fold increase (p<0.05) at peak inflammation. Enteric glia contribute to IL1β production and immunolabeling data showed a 40% increase in glial IL1β (p<0.05) that was confirmed by RNAseq data (2‐fold, p<0.05). The pro‐inflammatory mediators IL1β, IL6, INFy, and TNFα increased glial dye uptake under basal conditions and IL1β and IL6 potentiated ADP‐stimulated dye uptake by 24% and 53%, respectively (p<0.0001), in a Cx43‐dependent manner. The selective activation of glial cells with clozapine‐N‐oxide in GFAP::hM3Dq mice increased visceromotor responses to colorectal distensions (p<0.05) and drove pERK expression in TRPV1+ sensory nerve fibers in the myenteric plexus. Neither IL1β nor glial activation alone significantly affected Ca2+ responses to capsaicin in TRPV1+ nerve fibers in the colon. However, glial activation in the presence of IL1β significantly potentiated nociceptor Ca2+ responses to capsaicin and this effect required signaling through Cx43 hemichannels. Our data show that enteric glia can affect the sensitivity visceral nociceptors in the context of inflammation through mechanisms that include the potentiation of glial Cx43 hemichannel function by IL1β and the subsequent sensitization of TRPV1 channels expressed by sensory neurons.Support or Funding InformationNational Institute of Health through NIDDK: R01DK103723, R01DK120862
Comparison of Student Perceptions of Flipped Teaching in Undergraduate STEM Courses Across Two Institutions
Authors: Dickey Paige E , Fickas Julie , Bartels Lynn , Bracey Georgia , Locke Sharon , Gopalan Chaya 
Published: April 2020

Flipped teaching (FT) creates an environment to actively engage the learner as opposed to the often passive learning experience of traditional lecture‐based teaching (TT). Evidence has shown that FT can increase student engagement when lecture is shifted outside of the classroom through pre‐class activities while spending in‐class time working on activities at higher Bloom’s taxonomy levels. Research is lacking on which student population would benefit most from the FT. Six faculty from a four‐year institution and six faculty from a two‐year community college from STEM disciplines were selected to complete faculty development training on FT techniques. Upon completion of their training, faculty implemented FT in their classrooms the following semester. Student surveys were administered in each of these classes at the end of the semester. Students’ perception of engagement in the university STEM classes was significantly higher (p<0.0001) compared to community college STEM classes. Similarly, the university students’ level of confidence with the course material was significantly higher (p=0.0002) compared to the community college students. When overall attitude toward FT was assessed, the university students had a significantly more favorable attitude (p<0.0001) than the community college students. University students were significantly more likely to take another flipped course (p=0.0001) as well as recommend another student to take a flipped course (p<0.0001) than the community college students. Based on these results we conclude that students in the university setting have a more positive and receptive attitude toward FT compared to community college students.Support or Funding InformationNational Science Foundation
Musculature of the head and neck in naked mole‐rats (Heterocephalus glaber)
Authors: Thurber Mikaela , Diogo Rui , Sarko Diana 
Published: April 2020

Naked mole‐rats (Heterocephalus glaber) are eusocial, subterranean rodents from the family Bathyergidae. Their unusual anatomical and physiological traits, including a number of adaptations to their fossorial and eusocial niche, have been relatively under‐studied compared to other rodent species. They have large incisors that are used for social interactions (as well as defense); for navigation and object manipulation; for feeding; and for digging complex tunnel systems. In addition, naked mole‐rats have unusual oral folds that close caudal to their incisors, preventing dirt from entering their oral cavity while digging. They are functionally blind and have reduced pinnae. However, their well‐developed tactile system ‐ relying on their incisors as well as tactile hairs covering the entire body ‐ compensates for their reduced visual and auditory systems.Naked mole‐rat head and neck musculature might also be expected to have adapted to a subterranean niche and present with neotenic features. However, few studies to date have characterized naked mole‐rat musculature. To address this, we performed detailed anatomical dissections on adult naked mole‐rats in order to investigate the presence and attachment sites of the head and neck musculature. We found adaptations to a subterranean niche. For example, musculature associated with ear and eye movements was reduced. Overall, our findings provide insight into head and neck musculature as they relate to ecological and evolutionary adaptations, which can be placed within a comparative anatomical context based on what is present in other species.