bluuebunny/crossref_metadata_2025_split huggingface dataset:
Contribution of NLRP3 Inflammasome Activation to Glomerular Injury during Hyperhomocysteinemia with and without Enhanced Exosome Secretion
Authors: Huang Dandan , Li Guangbi , Camus Sarah , Li Ningjun , Ritter Joseph K. , Li Pin-Lan 
Published: April 2020

Hyperhomocysteinemia (hHcy) has been demonstrated to activate NLRP3 inflammasome leading to podocyte injury and glomerular sclerosis. However, it remains unknown whether exosome‐mediated secretion of NLRP3 inflammasome products is involved in the development of glomerular injury during hHcy. In the present study, we examined the possible role of increased exosome secretion during NLRP3 activation in the inflammatory response and tested whether without robust release of exosomes, inflammatory response and glomerular injury still occur. Exosome biogenesis inhibitor‐GW4869, lysosome trafficking stimulator‐rapamycin or ASM inhibitor‐amitriptyline were used in mice to answer this question. By nanoparticle tracking analysis, it was found that hHcy significantly increased urinary exosome release in WT/WT mice. In Smpd1trg/Podocre (podocyte‐specific ASM transgenic) mice, this hHcy‐induced increase in urinary exosomes was significantly enhanced. Pretreatments of WT/WT mice and Smpd1trg/Podocre mice with amitriptyline (Ami), GW4869 (GW) and rapamycin (Rap) all prevented increases in urinary exosomes during hHcy. In podocytes isolated from WT/WT mice and Smpd1trg/Podocre mice, similar results were obtained when we measured exosomes released from these cells after different treatments. Confocal microscopy demonstrated that Ami not only prevented hHcy‐induced NLRP3 inflammasome formation and activation in glomeruli, but also decreased exosome release in podocytes of WT/WT mice and Smpd1trg/Podocre mice. However, GW and Rap only blocked exosome‐mediated IL‐1β secretion from podocytes, but had no effect on inflammasome formation or activation in glomeruli during hHcy. However, all 3 treatments attenuated the inflammatory response in glomeruli and associated injury as shown by reduced immune cell aggregation, decreased proteinuria and ameliorated glomerular sclerosis. These results suggest that without enhanced exosome release NLRP3 inflammasome activation in podocytes may not produce local glomerular inflammatory response and associated injury during hHcy.Support or Funding InformationThis study was supported by NIH grants DK54927 and DK102539.
Assessing Bioavailability of Alaskan Blueberry Botanicals in vitro
Authors: Owen Savanah Renee , Collin Aline , Kuhn Thomas 
Published: April 2020

Prevalence of type II diabetes, a loss of insulin sensitivity, is rapidly increasing in rural Alaskan communities likely due to increasing obesity rates. However, there is a lower percentage of cases when compared to the incidence of type II diabetes in the contiguous US. This phenomenon could possibly be a consequence of berry‐rich diets as part of the traditional subsistence lifestyle of rural Alaskan populations. Wild Alaska blueberries, specifically, have been shown to improve or rescue insulin sensitivity in vitro. However, it is imperative to understand bioavailability, efficient uptake from the intestinal lumen into the bloodstream, to correlate these in vitro findings to in vivo situations. For this project, we modified an in vitro Caco‐2 bioavailability assay in order to mimic botanical transport by the intestinal lining. Caco‐2 monolayers used in these assays were tested for accuracy and intactness using both microscopy and transport studies. Transport studies were used to ensure monolayer integrity both prior to and after botanical transport, using 3kDa fluorescent dextran and Lucifer yellow as the control reporter molecule respectively. Results from this study provided insight into cell culture and cytotoxicity of botanical extracts, which can be used to improve upon the botanical bioavailability assay. Transported botanical extract from successful transport studies will be analyzed via LC‐MS and compared to a full, untransported extract control.Support or Funding InformationResearch reported in this publication was supported by the National Institute Of General Medical Sciences of the National Institutes of Health under Award Numbers UL1GM118991, TL4GM118992, or RL5GM118990. The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Institutes of Health.Research reported in this publication was supported by an Institutional Development Award (IDeA) from the National Institute of General Medical Sciences of the National Institutes of Health under grant number P20GM103395. The content is solely the responsibility of the authors and does not necessarily reflect theofficial views of the NIH.
Genetic Testing of a Puerto Rican Family Trio with Oculocutaneous Albinism Type 1B Reveals a Misdiagnosis of Hermansky‐Pudlak Syndrome
Authors: Serrano Joseline , Montes Ingrid M. , Renta Jessicca Y. , Rojas Ricardo , Cadilla Carmen L. 
Published: April 2020

Hermansky‐Pudlak syndrome (HPS) is a rare autosomal recessive disorder where the biogenesis of lysosomal‐related organelles is affected. Clinical manifestations depend on the type of HPS, and frequently include a hemorrhagic diathesis, oculocutaneous albinism and a lysosomal storage disease. Some types of HPS manifest with pulmonary fibrosis, granulomatous colitis, neutropenia, immunodeficiency and neurological symptoms. Up to date, 10 types of HPS have been reported, each arising from mutations in different genes. In Puerto Rico, HPS is caused primarily by founder mutations in the HPS1 and HPS3 genes. The present study aims to determine the genetic defects in a Puerto Rican family trio that does not harbor the HPS1 and HPS3 founder mutations. The proband presented with ocular albinism, reduced number on platelet dense bodies, neutropenia, and gastroesophageal reflux disease, which led clinicians to diagnose her with HPS. Exome sequencing was performed for the family trio using blood samples, where single nucleotide variants in several HPS genes as well as the Tyrosinase gene (TYR) were found. The proband carries three TYR gene amino acid changes: G47D, S192Y, and R402Q. The pathological G47D mutation has been previously detected in Puerto Rican oculocutaneous albinism type 1 (OCA1) patients who were homozygous for these mutations. The proband’s father carries the G47D and S192Y variants, but the R402Q is a de novo mutation in the proband. The R402Q amino acid change is frequently found in Caucasians (MAF=.252) and Puerto Ricans (MAF=0.183) and makes TYR a temperature‐sensitive enzyme. The TYR gene mutations detected would imply that the proband has very low TYR activity. Both the S192Y and the R402Q variants have been proposed to have combinatory variant effects with other more severe OCA1 mutations. Our findings suggest that the combination of common and pathological TYR alleles may be the cause of the proband’s albinism, and that the other clinical manifestations may be unrelated or due to the other mutations found in HPS genes. This study supports previous work that proposed that the common S192Y and R402Q TYR alleles combined with a deleterious mutation can cause OCA1B, but their clinical relevance still need to be investigated further since there is also evidence that homozygosity for R402Q does not cause OCA. The clinical relevance of supposedly benign HPS gene SNPs also deserves further studies.Support or Funding InformationThis research was supported in part by RCMI grants U54 MD007600 and U54MD007587 (National Institute on Minority Health and Health Disparities), RISE grant R25GM061838 and PR INBRE grant P20GM103475 (National Institute of General Medical Sciences).
Essential Anatomy for Anesthesiology in the Undergraduate Medical Curriculum
Authors: Harmon Derek , Hankin Mark , Martindale Jim , Davies David , McNary Thomas , Sanky Charles , Laitman Jeffrey , Reidenberg Joy S , Keim Sarah , Miriyala Sumitra , Pratt Rebecca , Lopez Lisa , Doroudi Majid , Topping Daniel , Royer Danielle , Cotter Meghan 
Published: April 2020

IntroductionTo prepare medical students for clinical training and practice, it is critical to understand the anatomical knowledge considered most important for different clinical specialties.AimTo address this issue, a consortium of anatomists in the US and Canada is collecting data from clinical educators in Anesthesiology clerkships and electives to identify the anatomy they consider essential.MethodsAn IRB‐approved, online survey (Qualtrics, Seattle, WA) was used to assess the importance of 98 anatomical topics in seven body regions. The study first examined the percentage of Anesthesiology clinical educators (clerkship/elective directors and attending physicians) that considered each anatomical region important to their specialty. Second, the study examined the rank assigned to each anatomical topic using an ordinal scale from 1 (not important) to 4 (essential).ResultsAt the time of abstract submission, data had been collected from 21 Anesthesiology clinical educators at 14 medical schools. The percentage of Anesthesiology clinical educators that considered each anatomical region important to their specialty were (highest‐to‐lowest): Back (100%), Head & Neck (100%), Thorax (95%), Upper Limb (86%), Lower Limb (86%), Abdomen (80%), and Pelvis & Perineum (50%). Further data analysis has identified the highest ranked anatomical topics in each body region for the Anesthesiology clerkship/elective.Discussion and ConclusionThis database provides detailed information regarding the most clinically relevant anatomical topics as identified by Anesthesiology clinical educators. This information can aid in focusing preclinical learning to best prepare medical students for success in their undergraduate and graduate clinical experiences.
Characterization of Sodium Bicarbonate Transporters NBCe1 and NBCn1 as CO2 channels
Authors: Wang Dengke , Boron Walter F. 
Published: April 2020

The known “gas channels” are members of the AQP and Rh families, and appear to conduct CO2 mainly through the stable hydrophobic central pores of these multimeric proteins. The present work helps to define a new class of gas‐conduction pathway: transporters that may conduct CO2 through cracks that form transiently as the protein cycles through various conformations—much like H2O can leak through certain membrane proteins. To identify CO2 channels, we developed a novel tool—expressing AQP5 in Xenopus oocytes, followed by injection of small amounts of carbonic anhydrase II (CAII), and then exposure of the cell to CO2/HCO3− solutions. Cytosolic CAII promotes the consumption of incoming CO2, thereby maintaining a low [CO2] at the inner surface of the cell membrane, and maximizing the gradient for CO2 influx. A semiquantitative measure of this CO2 influx is the spiking increase in surface pH (DpHS) that occurs as CO2 enters the cell, lowers [CO2] at the outer surface of the cell membrane, causes some HCO3− in the vicinity of the membrane to undergo the reaction HCO3− + H+ ® H2O + CO2, and thereby replenishes some of the lost CO2. The pHS spike is greatest near time‐zero, when the inward CO2 gradient—and thus the reaction HCO3− + H+ ® H2O + CO2—is greatest, and then exponentially wanes as CO2 equilibrates across the cell membrane. Oocytes expressing AQP5 and then injected with Tris buffer (but not CAII) have a much greater DpHS than controls injected with H2O (not cRNA) and Tris (not CAII), confirming that AQP5 is an excellent CO2 channel. Injecting a small amount of CAII (dissolved in Tris) into oocytes not expressing AQP5 produces only a slight increase in DpHS because the rate‐limiting step is membrane CO2 permeability. However, for AQP5‐expressing oocytes, injecting this same small amount of CAII produces a very large increase in DpHS. In other words, the CAII‐dependent change in spike height—D(DpHS)—is much greater in AQP5‐expressing oocytes than H2O‐injected controls. We conclude that the measured D(DpHS) in ±CAII experiments is a powerful tool for assessing CO2 conductance. We applied this method to measuring the CO2 conductance of Na/HCO3 co‐transporters, NBCe1‐A and NBCn1‐G. Preliminary data show that, in the presence of cytosol CAII, D(DpHS) is >1.5‐fold greater in the oocytes expressing NBCe1‐A than the H2O‐injected controls, supporting the hypothesis that NBCe1‐A has a CO2 conductance. Similarly, D(DpHS) is >5‐fold greater in the oocytes expressing NBCn1‐G than the H2O‐injected controls, supporting the hypothesis that NBCn1‐G has a CO2 conductance.Support or Funding InformationSupported by grants GM111251 (the U grant) and N000141612535 (the MURI grant)
Chronic Stress Alters Expression of Vomiting‐related Receptors in CNS in SD Rats
Authors: Li Zhuman , Xu Feng 
Published: April 2020

Chemotherapy‐induced nausea and vomiting (CINV) are extremely painful side effects that occur frequently in cancer patients during chemotherapy. Our previous study found that cancer patients have high incidence of depression that correlate positively with CINV. However, whether depression aggravate the CINV is not clear up to now. In this report, we established chronic unpredictable mild stress‐induced depression model in SD male rats. The vomiting‐related receptors including serotonin 3 receptor (5‐HT3R), dopamine receptor (DA2R), endogenous cannabinoid receptor (CB1R) and substance P receptor (NK1R) in the posterior region of the fourth ventricle and in the medulla were studied by qRT‐PCT and Western blotting analysis. Blood levels of 5‐HT, DA, AEA and substance P were measured by ELISA. There were significant difference in behavioral evaluation scores between the model rats and control rats, indicating depression model was successfully built up in model rats. Compared with control rats, blood levels of 5‐HT, DA and substance P were significantly decreased while AEA was significantly increased in model rats, the mRNA and protein of expression levels of 5‐HT3R, DA2R, NK1R were increased while CB1R were decreased in model rats. In conclusion, chronic stress altered expression of vomiting‐related receptors in CNS in SD rats.Support or Funding InformationShanghai Science and Technology Commision Plan Project (No. 19411971700)
Mechano‐Electric Coupling and Arrhythmogenic Current Generation in a Multi‐Scale Computational Model of Coupled Myocytes
Authors: Timmerman Viviane 
Published: April 2020

Heterogeneous mechanical activity during acute myocardial ischemia is thought to contribute to arrhythmogenic alterations in cardiac electrophysiology. Stretch‐induced perturbations to cardiomyocyte electrophysiology may trigger arrhythmias via a variety of mechano‐electric coupling (MEC) mechanisms. While the role of stretch‐activated ionic currents has been investigated intensively using computational models, experimental studies have shown that mechanical strain can also trigger intra‐ and inter‐cellular calcium waves. To assess whether the inherent stretch dependence of myofilament calcium affinity may promote ischemia‐induced arrhythmogenic intra‐ and inter‐cellular calcium waves, we coupled a mathematical model of excitation‐contraction coupling in rabbit ventricular myocytes to a model of myofilament activation and force development. The model was modified to mimic observed electrophysiological alterations during ischemia, and was subjected to systolic stretch.We compared a zero‐dimensional (0D) and one‐dimensional (1D) compartmental analysis, for which multiple myocytes were electrically and mechanically coupled in series. In the 1D model each myocyte consisted of 50 bi‐directionally coupled electromechanical models in addition to calcium diffusion and strain transfer between adjacent units. Both, the 0D and 1D model, were fitted to calcium alterations during homogeneous stretch transient. The addition of end‐to‐end mechanical interactions of inter‐ and/or intracellular sarcomeres enabled the model to capture: (1) the effects of MEC on intracellular calcium dynamics at the sarcomeric scale; and (2) the effects of mechanical heterogeneities on calcium dynamics at the cellular scale.The simulation results suggest that in the 0D only the triggers of calcium‐mediated delayed after depolarizations (DADs) could be observed. In the 1D model, in conditions of calcium overload and only for the non‐ischemic myocytes, an increase in stretch or an increase in sarcomere heterogeneity increase the susceptibility for myofilament triggered calcium waves causing DADs. Additionally, the specific sarcomere heterogeneity can modulate intracellular calcium dynamics which may increase susceptibility to pro‐arrhythmic intra‐ and inter‐cellular calcium wave propagation, but only for spatially explicit myocyte models.
Codeine Reconfigures The Respiratory Network In The Cat
Authors: Bolser Donald C. , Segers Lauren S. , Nuding Sarah C. , Baekey David M. , Morris Kendall F. 
Published: April 2020

The mechanisms responsible for depression of breathing by opioids are poorly understood. Multiple regions of the brainstem have been implicated in respiratory depression, including the pre‐Bötzinger complex and pons. At the network scale, evidence exists that opioids act at sites that are presynaptic to medullary premotor and motoneurons. We speculated that opioids reconfigure the respiratory network at doses that are subthreshold for depression of breathing. Cats (n=11) were decerebrated, paralyzed, and artificially ventilated. Extracellular action potentials of neurons in the region of the nucleus of the tractus solitarius (NTS), raphe and ventral respiratory column (VRC) were recorded in the brainstem from multiple electrode arrays. Codeine (0.009–4.9 mg/kg) was administered via the vertebral artery. The discharge identity (pattern of discharge during breathing) of 63/148 recorded neurons changed after codeine administration relative to control. Of the 56/168 neurons that were not breathing modulated, 31/56 (55%) became respiratory modulated after codeine. Ninety‐two neurons were respiratory modulated in the control period and 32 (35%) of these either were not modulated during breathing or altered their respiratory pattern after administration of codeine. Cross correlation analysis indicated that functional correlations consisting of offset peaks/troughs or central peaks were detected during the control period between 56 pairs of neurons whereas 75 pairs were correlated after codeine. Feature maps of putative circuits in each experiment suggested significant reorganization of the respiratory network after codeine. Clusters of VRC inspiratory neurons exhibited significant alterations in functional correlations consistent with altered synchrony. Features in cross correlation histograms during codeine administration typically appeared early in the dose response rather than being restricted to the highest dose, consistent with a high sensitivity to the drug. Most of the features in cross correlation histograms appeared at doses that were lower than those that produced significant depression of breathing. These results support opioid‐induced reconfiguration of the respiratory network. Alternate hypotheses regarding the functional manifestation of this reconfiguration include a) compensatory responses of the network as sensitive neuron populations are affected by increasing doses of opioids, and b) dysregulation of synchrony as a prerequisite to respiratory depression.Support or Funding InformationSupported by HL131716
Neuronostatin Induces C‐FOS Response and Gluconeogenic Enzymes in HEPG2 Cells: A Potential Role of Neuronostatin in the Liver
Authors: Mahmood Ammar , Grote Stephen , Samson Willis , Yosten Gina 
Published: April 2020

Hepatic glucose production (HGP) and output are regulated by a complex system of hormones, receptors, signaling mechanisms, glycolytic and gluconeogenic enzymes, and many overlapping transcription factors. The proteins involved in HGP are attractive targets for antidiabetic therapy, yet better pharmacological interventions are still needed for treatment. Therefore, it is critical to identify and characterize new targets within HGP regulation. We identified a novel peptide, neuronostatin, encoded in the somatostatin prohormone that exerts effects in the central nervous system, the heart, and the pancreas. Neuronostatin is produced in the delta cells of the pancreatic islets and plays an important role in maintaining glucose homeostasis through enhancing glucagon secretion from the α cell and reducing insulin release from the β cell. In male rats, a bolus injection of neuronostatin significantly increased blood glucose over 30 minutes after administration. Likewise, the peptide delayed glucose clearance and diminished the insulin response to hyperglycemia in a glucose tolerance test. Our group also identified the orphan GPCR, GPR107, as a cognate receptor for the peptide. GPR107 is expressed in numerous tissues, including the liver.In searching for the role of neuronostatin in hepatic physiology, we observed that hepatocellular carcinoma cell line HEPG2 expressed GPR107. Thus, we hypothesized that neuronostatin would elicit a biologic effect on the liver using HEPG2 cell line as in‐vitro model. We found that treatment of HEPG2 cells with neuronostatin significantly elevated cFos mRNA expression, indicating that HEPG2 cells respond to the peptide. In addition, neuronostatin induced expression of gluconeogenic enzymes, such as phosphoenolpyruvate carboxykinase and glucose‐6‐phosphatase. These results indicate potential effects of neuronostatin on HGP, so we sought to determine if the effects of neuronostatin on blood glucose were due to increased glucagon secretion or due to a direct effect in the liver. In rats treated with a glucagon receptor antagonist, neuronostatin increased blood glucose, supporting a glucagon‐independent action on HGP. Thus, our results suggest that neuronostatin could play a physiologically relevant role in the liver and that GPR107 may be a new target in hepatic glucose production.Support or Funding InformationNational Institute of Health
Pulmonary microvascular dysfunction develops in rodent models of HFpEF
Authors: Czikora Istvan , Davila Alec C. , Tian Yanna , Belanger Kasey , O'Connor Paul , Sullivan Jennifer C. , Bagi Zsolt 
Published: April 2020

Pulmonary complications are common in patients with diastolic heart failure, also known as heart failure with preserved ejection fraction (HFpEF). We tested the hypothesis that pulmonary microvascular dysfunction develops in HFpEF. We employed two different rodent models of HFpEF, uninephrectomized and DOCA (UNX‐DOCA) salt treated rats as well as uninephrectomized aldosterone (UNX‐Aldo) infused mice. Left ventricle (LV) diastolic function was assessed by transthoracic echocardiography (E/A ratio and deceleration time). Microvascular vasodilator function in rats was examined in isolated small pulmonary arteries (3rd or 4th order) using wire myography, whereas pulmonary vascular resistance (PVR) was measured in isolated perfused lungs in mice. Our results showed that LV diastolic dysfunction and increased pulmonary edema formation was accompanied by a reduced acetylcholine‐induced pulmonary artery relaxation and increased PVR in UNX‐DOCA rats and UNX‐Aldo mice, respectively, when compared to corresponding controls. Responses to the direct nitric oxide donor, sodium nitroprusside were maintained and found to be similar in the magnitude in the different groups. We also found that these functional changes were accompanied by a reduced artery lumen diameter and increased wall thickness in UNX‐DOCA rats and UNX‐Aldo mice. We concluded that both functional and morphological changes develop in the pulmonary microcirculation that could contribute to pulmonary complications, such as edema formation and pulmonary artery hypertension in HFpEF.Support or Funding Information1R01AG054651‐0117SDG33680024