bluuebunny/crossref_metadata_2025_split huggingface dataset:
Locally formed Peroxynitrite inhibits endothelial TRPV4 channels and elevates blood pressure in obesity
Authors: Ottolini Matteo , Hong Kwangseok , Cope Eric Lee , Daneva Zdravka , Johnstone Scott R. , Isakson Brant , Sonkusare Swapnil K. 
Published: April 2020

Impaired endothelium‐dependent vasodilation is a hallmark finding of obesity‐induced hypertension. Recognition that Ca2+ signaling in endothelial cells promotes vasodilation has led to the hypothesis that endothelial Ca2+ signaling is compromised during obesity, but the underlying abnormality is unknown. Here, we show that Ca2+ influx through TRPV4 channels at myoendothelial projections (MEPs) to smooth muscle cells lowers resting blood pressure in non‐obese mice, a response that is diminished in obese mice. Counter‐intuitively, release of nitric oxide (NO) from endothelial cells attenuates TRPV4 channel activity and TRPV4‐mediated vasodilation in the obese animals. Increased activities of iNOS and NOX1 correlated with elevated levels of NO and superoxide radicals at the MEPs in obese mice, ultimately reacting to form peroxynitrite. Subsequent findings revealed that peroxynitrite causes cysteine oxidation of the regulatory protein AKAP150 to inhibit TRPV4 channel activity at the MEPs. TRPV4 channel activity and vasodilation are also impaired in the arteries from obese patients, and are restored by strategies that lower peroxynitrite levels. These data suggest that defective TRPV4 channel–mediated vasodilation may contribute to obesity‐induced hypertension, and imply that inhibiting peroxynitrite may represent a strategy to normalize endothelial TRPV4 channel activity, vasodilation and blood pressure during obesity.Support or Funding InformationHL121484‐01, HL138496
Enalapril‐associated combined training is most effective in reducing SBP in spontaneously hypertensive rats
Authors: de Araujo Amanda Aparecida , Shecaira Tânia Plens , Paixão Camila , da Silva Dias Danielle , Irigoyen Maria Cláudia , De Angelis Kátia 
Published: April 2020

High blood pressure is the leading risk factor to development of cardiovascular disease worldwide. Diuretic and angiotensin‐converting enzyme blockers treatment is widely used for its efficiency in reducing blood pressure (BP). Combined physical training (aerobic + resistance) is recommended for hypertensive patients, however, it is not yet clear whether the combination of antihypertensive treatment with this training modality results in additional benefits. Therefore, the aim of this study was to compare the effects of combined training with different drug treatments on systolic BP (SBP) of spontaneously hypertensive rats. Twenty‐eight SHR rats were divided into four groups (n=7/group): HSM (hydrochlorothiazide sedentary males), HTM (hydrochlorothiazide trained males), ESM (enalapril sedentary males) and ETM (enalapril trained males). Drugs were administered in drinking water at the following doses: enalapril 10 mg/kg/day and hydrochlorothiazide 30 mg/kg/day. All groups underwent exercise testing before and after 2 months. The trained groups performed combined training 3 times a week, being aerobic and resistance at same session, moderate intensity. The SBP was analyzed by caudal plethysmography before starting the drugs and 24h after the last training session. As a result, only HTM group increased the body weight (HTM vs. HSM, p=0.001). Both trained groups increased maximal aerobic exercise test (p<0.0001) and resistance exercise test (HTM vs. HSM, p=0.02; ETM vs. ESM, p<0,0001) versus the group control. We observed that there was no difference in the initial SBP between the groups (HSM 176±4.3, HTM 175±3, ESM 173±1.4 and ETM 183±3 mmHg) and there was a reduction in the HTM (161±1.3 mmHg), ESM (159 ± 4.4 mmHg) and ETM (147 ± 3.3 mmHg) groups. In addition, the trained group associated with enalapril treatment further reduced SBP when compared to the hydrochlorothiazide‐trained group (ETM vs. HTM, p=0.02). Therefore, the data support that the combination of drug treatment with enalapril and combined physical training in the same training session is more effective in reducing blood pressure than the combination with hydrochlorothiazide. It is noteworthy that the training proposed in this study was performed three times a week, getting closer to human reality and being enough for additional benefits in the control of blood pressure of spontaneously hypertensive rats.Support or Funding InformationCAPES
GPER Contributes to the Development of Pulmonary Hypertension in Female Rats
Authors: Ahmadian Rosstin , Sheak Joshua R. , Weise-Cross Laura , Jernigan Nikki L. , Arterburn Jeffrey B. , Prossnitz Eric R. , Snow Jessica B. , Resta Thomas C. 
Published: April 2020

Studies from our group and others demonstrate a protective role of estrogen in attenuating the progression of chronic hypoxia (CH)‐induced pulmonary hypertension. Physiological responses to estrogen are mediated by the nuclear estrogen receptors a and b, as well as by the membrane‐bound G protein‐coupled estrogen receptor (GPER). However, the role of GPER in the development of pulmonary hypertension resulting from CH is unknown. We hypothesized that GPER acts to limit the severity of CH‐induced pulmonary hypertension.To test this hypothesis, we evaluated indices of pulmonary hypertension in control and CH (4 wk, PB = 0.5 atm) female rats administered the GPER antagonist G36 via osmotic pumps (1 mg/kg/day, s.c.) during the entire 4 wk exposure period (n=7–8/group). Right ventricular systolic pressure (RVSP) was measured using a fluid‐filled catheter advanced through the right jugular vein into the right ventricle (RV) during isoflurane anesthesia. Additionally, RV hypertrophy was determined from Fulton’s index [RV/(LV+S)], and the polycythemic response to CH was assessed by measuring hematocrit.CH increased RVSP, Fulton’s Index, and hematocrit in vehicle‐treated rats (P<0.0001), indicative of pulmonary hypertension and associated polycythemia. Unexpectedly, RVSP was lower in G36‐treated CH rats compared to control animals (P<0.05), with a downward trending Fulton’s Index (not significant). However, hematocrit was unaltered by GPER inhibition. We conclude that GPER mediates a novel effect to facilitate the development of pulmonary hypertension resulting from CH exposure.Support or Funding InformationNIH Grants R01 HL132883, T32 HL007736, and P20 GM103451. AHA Grant 18AIREA33960020
Mathematical model of oncolytic virotherapy with Myxoma virus infection in cancer cells
Authors: Ortegon Sofia , Franco Lina S. , McFadden Grant , Cordovez Juan 
Published: April 2020

Oncolytic virotherapy is an innovative alternative to more conventional cancer therapies that is based on the ability of oncolytic viruses to specifically target and kill tumor cells. This therapy can activate the innate and adaptive immune response of the body achieving the destruction of cancer cells by the immune system. Myxoma virus is a poxvirus that infects in European rabbits, can also replicate in a variety of human cancer cells lines, which makes it an ideal candidate for oncolytic virotherapy. However, the dynamic mechanisms between the virus and the cancer cells are not completely understood. Mathematical models are useful tools to provide relevant insights about the dynamics that govern the interplay between normal and cancer cells and their viral parasites. In this study murine melanoma cancer cells were infected with a Myxoma virus expressing GFP (vMyx GFP) at low multiplicity of infection and pictures were taken in a fluorescence microscope every 30 minutes to determine infected cells. To understand the process of infection, namely the susceptible to infected conversion rates and the spatial effects of cell culture, we developed a mathematical model parameterized with the experiments described above that spatially explicitly simulates the process of infection. The model is an stochastic spatially explicit SI formulation that considers cancer cells and viral particles. With the model we were able to quantify and better understand this complex network of interactions. We were able to estimate important parameters concerning infection, proliferation and spatial dependency. We hope that the model will contribute to accelerate the development of a functional and effective oncolytic virotherapy with Myxoma virus.Support or Funding InformationOffice of the vice‐presidency of research at los Andes University
TMEM184A: Evidence for a Potential Link Between HSPGs and Mechanotransduction
Authors: Talotta-Altenburg Leanna M. , Ciabattoni Grace O. , Laessig Minuette A. , Lowe-Krentz Linda J. 
Published: April 2020

Heparin is a known anticoagulant that, with cellular uptake, contributes to a variety of physiological conditions, including experimentally observed decreases in vascular cell proliferation and inflammation. The fact that heparin is endocytosed and decreases cellular responses rather than blocking them entirely suggested a receptor mediated model, which has been previously identified in our laboratory as TMEM184A. Our data suggest that TMEM184A associates with vascular endothelial‐cadherin (VE‐Cadherin) and heparan sulfate proteoglycans (HSPGS), modulating mechanotransduction events in response to heparin treatment and fluid shear stress (FSS), which replicates the stress induced by blood flow under physiological conditions. TMEM184A seems to play a role in trafficking HSPGs such as syndecan‐1 (SDC1) and glypican‐1 (GPC1), both of which have been characterized as mechanosensing proteoglycans. In recent studies it has been demonstrated that VE‐Cadherin may interact with HS chains. Data in the literature have shown that when HS chains are degraded by Heparinase III treatment, the strain induced decrease in VE‐Cadherin is abolished, indicating that the HSPGS are crucial in sensing the strain. Given these findings, as well as our preliminary evidence that TMEM184A associates with HSPGs, we hypothesize that TMEM184A acts as an interface in the mediation of mechanosignaling events on the extracellular surface of adherens junctions. Co‐immunoprecipitation pull down of TMEM184A followed by subsequent western blotting and immunostaining showed both VE‐Cadherin and TMEM184A in the bound supernatant, indicating that the two may colocalize at endothelial adherens junctions and associate in a mechanosensing complex. Using a GFP‐TMEM184A plasmid construct to overexpress TMEM184A in bovine aortic endothelial cells (BAOECS), our research team observed increased surface levels of VE‐Cadherin in adherens junctions under static flow conditions. These overexpressing cells were subjected to FSS, which increases TMEM184A associations with HSPGs. Our team observed an additive increase in VE‐Cadherin in adherens junctions when compared to overexpression alone in static conditions. An additional experiment done to elucidate the role of endogenous heparin (HSPGs) revealed that BAOECs washed with a concentrated salt buffer to remove HPSG‐protein interactions demonstrated decreased colocalization of VE‐Cadherin, TMEM184A, and various vesicle associated membrane proteins. The addition of heparin rescued these colocalization events, implicating HSPGs in this complex. Our ongoing work aims to elucidate how associations of TMEM184A with VE‐cadherin and HSPGs facilitate activation of mechanically induced signals and mediate the trafficking of adherens junctions’ surface proteins.Support or Funding InformationHL54269 to LJLK
Investigating the Role of Introns in Transcription‐Associated Mutagenesis in Budding Yeast
Authors: Lansangan Cedric Kier , Kim Jane 
Published: April 2020

A key feature required for cell survival is genomic stability, which is the ability of a cell to prevent mutations in its genome and repair them if they do occur. Genomic mutations can be generated in several ways, including transcription of a gene via transcription‐associated mutagenesis (TAM). Introns are known to be able to enhance transcription in vivo, but the influence of introns on TAM is not well‐understood. Here, our work investigates whether introns modulate the rate of TAM in a URA3 reporter gene using budding yeast as a model organism. Our preliminary results suggest that the presence of introns in the natively‐intronless URA3 gene is associated with elevated mutation rates of that gene. Interestingly, there appears to be an intron‐length‐dependent effect on this trend (i.e. the yeast strain with a long intron in the URA3 reporter demonstrated elevated URA3 gene mutation rates compared to the other two strains with either a short intron or no intron). Our findings suggest that the length and presence of introns in a gene are associated with increased mutagenesis of that gene. Furthermore, the long‐intron‐containing strains in our study grew slower in the absence of uracil than the short‐intron strains and no‐intron controls, possibly indicating an effect of intron length on splicing of the URA3 primary transcript. We are currently investigating if elevated transcription rate of a URA3 gene containing an intron causes an increase in TAM rate. In addition, URA3 reporter gene expression levels are being quantitated in each strain. We expect that URA3 mRNA transcript levels will be elevated in the intron‐containing URA3 yeast strains relative to those of the no‐intron controls. In future work for this study, we will determine the effect of the presence of an intron located near the promoter of an induced URA3 gene on the rate of TAM. Our future results will contribute to better understanding the impact of introns on the mutagenesis of highly‐expressed genes, which may play a role in mechanisms underlying mutagenesis in the human genome.Support or Funding InformationDr. Jane Kim’s research is supported by an NIH SCORE Grant (SC3GM127198).
Characterization of Extracellular Vesicle LINE‐1 mRNA, Protein, and Reverse Transcriptase Activity Profiles
Authors: Bowers Emma , Cavalcante Alexandre , McKay Brian , Ramos Kenneth 
Published: April 2020

Lung cancer has the highest mortality rate among all cancers, making early detection of this malignancy imperative for survival. Ongoing studies in our laboratory have focused on developing Long Interspersed Nuclear Element‐1 (LINE‐1) in circulating lung extracellular vesicles (EVs) as a novel mechanism‐based ‘liquid biopsy’ for lung cancer. LINE‐1 is a mammalian retroelement that can ‘copy and paste’ itself and other DNAs into different loci via a reverse transcriptase‐mediated mechanism. While LINE‐1 is epigenetically silenced in most healthy cells, its activity can be initiated by harmful environmental exposures and is strongly associated with cancer risk and mortality. Evidence is presented here that LINE‐1 mRNA and protein are present in EVs isolated from H460 lung cancer cells and human plasma and are segregated into distinct EV populations. Because reverse transcription (RT) of LINE‐1 requires formation of a ribonucleoprotein complex containing LINE‐1 mRNA and proteins, we hypothesize that this segregation has been engineered to control RT. In support of this hypothesis, we found that RT activity is only present when these two EV populations are lysed and combined. We then isolated EVs from ostensibly healthy plasma donors and found substantial inter‐individual variability with respect to LINE‐1 protein, mRNA, and RT activity. The variability between individuals and the ease of measurement from clinical samples further supports the use of these LINE‐1 metrics as health‐related biomarkers. After characterizing EV LINE‐1, we sought to determine whether EV LINE‐1 levels could serve as a proxy of cellular LINE‐1 content, which is critical to our overall goal of using isolated lung EVs as a liquid biopsy of the lung epithelium. Using a panel of six different lung epithelial cell lines, we compared baseline LINE‐1 expression between cells and EVs. We also treated lung epithelial cells with different concentrations of benzo(a)pyrene (BaP), a cigarette smoke carcinogen known to induce LINE‐1, and compared LINE‐1 levels in cells and EVs. Thus far we discovered that, in both baseline and toxicant‐induced scenarios, EV LINE‐1 mRNA levels mirror cellular levels. Together, these data demonstrate that EV LINE‐1 content and RT activity can be quantified in cultured cells and clinical samples and supports the use of EV LINE‐1 cargo as a biomarker of lung epithelial cell status.Support or Funding InformationThis work was funded in part by grants from the University of Arizona Health Sciences, the Southwest Environmental Health Sciences Center (P30 ES006694), the National Cancer Institute Cancer Center Support Grant (P30CA023074), the UAZ Bio5 Fellowship and GURI Texas.
A Flexible and Reproducible Framework for Modelling Renal Tubules
Authors: Nickerson David Phillip , Sarwar Dewan , Noroozbabaee Leyla , Kalbasi Reza , Atalag Koray , Hunter Peter 
Published: April 2020

We have developed a new framework for defining renal tubule models utilising a repository of existing models from the literature. The CellML format (
https://cellml.org) is an XML format for encoding mathematical models ‐ typically used for lumped parameter, non‐spatial models of physiological systems. We have previously demonstrated how models of epithelial transport processes can be discovered in public model repositories such as the Physiome Model Repository (
https://models.physiomeproject.org) and reused in building novel models at the epithelial cellular spatial scale.In this work we present a novel Python‐based framework in which we extend our previous work to now look at solute transport and flow in generic tubule segments. The Python code captures the standard equations for flow and solute transport and we link to CellML descriptions of transport mechanisms to define the transport of solutes between the lumen, intracellular space, and interstitial fluid.By linking to models of, for example, epithelial transport proteins encoded in the CellML format we are able to configure the generic tubule segment to represent known physiology of the various nephron segments in the kidney. As the number and variety of suitable models in the model repository grows, we will be able to “automatically” discover and utilize them in this framework.In future work, we will are attempting to utilize clinical data captured in semantic knowledge frameworks, such as openEHR, to guide the discovery and parameterization of the epithelial cellular transport processes based on clinical or experimental observations.Support or Funding InformationWe gratefully acknowledge funding from the Aotearoa Foundation, Medical Technologies Centre of Research Excellence, and the Auckland Bioengineering Institute.
Regional Effects of Monoamine Transporter Blockers on Extracellular Monoamine Levels
Authors: Harris Sharonda , Green Sara M. , Garber Lexi , Urs Nikhil M. 
Published: April 2020

Monoamine transporter inhibitors are used in the treatment of a number of psychiatric disorders, including major depression and ADHD, and have high abuse potential. These drugs increase extracellular levels of monoamines by blocking the reuptake of monoamines through their respective transporters. Although selective norepinephrine (NE), dopamine (DA) and serotonin (5‐HT) transporter inhibitors increase NE, DA and 5‐HT, respectively, through blockade of their cognate transporter, there is substantial evidence showing that these selective inhibitors can also block the reuptake of monoamines from non‐cognate transporters. For example, studies have shown that norepinephrine transporter (NET) inhibitors can increase extracellular NE and DA levels in the PFC and hippocampus. Studies have also shown increased extracellular NE, DA and 5‐HT levels in the PFC by administration of a selective serotonin reuptake inhibitor (SSRI). Moreover, studies from dopamine transporter (DAT) and serotonin transporter (SERT) KO mice have also shown that selective NET and SERT blockers can increase extracellular DA levels in both the PFC and striatum. Although these non‐selective effects have been reported, there has not been a systematic investigation of brain‐region specific effects of selective monoamine transporter inhibitors on extracellular monoamine levels. We therefore sought to determine the effects of selective inhibitors of monoamine transporters on extracellular monoamine levels in the prefrontal cortex (PFC), nucleus accumbens (NAcc) and dorsal striatum (dStr). We used an ex vivo neurotransmitter release assay to determine the dose‐dependent effects of a NET inhibitor, desipramine, a DAT inhibitor, GRB 12909 and a SERT inhibitor, fluoxetine, on extracellular NE, DA and 5‐HT from PFC, NAcc, and dStr slices of wild‐type (WT) mice. We also examined the dose‐dependent effects of amphetamine on extracellular monoamine levels in the brain regions of interest of WT mice. The findings from WT mice were subsequently compared to those obtained from DAT and NET knockout mice. The results show that selective blockade of NET, DAT and SERT increase extracellular levels of NE, DA, and 5‐HT respectively, as well as alter the extracellular levels of non‐selective monoamines in a brain‐region and genotype specific manner. These findings will guide future studies exploring how region‐specific changes in monoamine levels affect the activity of neuronal circuits, physiology and behavior.Support or Funding InformationBBRF/NARSAD Young Investigator award to Nikhil Urs
Connexin/gap junctions and cytoskeletons synergistically control lens fiber cell morphogenesis and metabolism
Authors: Gong Xiaohua , Li Rachel , Xia Chun-hong 
Published: April 2020

We have investigated the underlying mechanisms for how a loss of the Gja3 gene (encoding Cx46) leads to variable nuclear cataracts between the C57BL/6J (B6), 129SvJae (129) and B6/129 strain backgrounds, and determined how the genetic variances of periaxin (encoding a cytoskeletal scaffold protein) and CP49 (encoding an intermediate filament protein) modulate the cataract formation. We hypothesize that the Cx46 gap junctions and cytoskeletons synergistically support lens transparency by not only controlling the fiber cell morphogenesis during development but also regulating the exchanges of metabolites between fiber cells to maintain lens homeostasis. Using genetic manipulation and confocal imaging analysis, we have found that both B6‐CP49 and B6‐periaxin inhibit the severity of nuclear cataracts and that the 129‐periaxin proteins are predominantly colocalized with F‐actin and associated with abnormal protrusions on fiber cell surface. The degree of disrupted inner fiber cell surface topology is correlated with the severity of nuclear cataract formation. Metabolite profiling has revealed changes of antioxidants, glycolysis pathway intermediates and lipids compositions in Gja3 knockout (KO) lenses of different strain backgrounds. The Gja3 KO lenses have significant lower levels of glutathione (GSH) than wild‐type controls. Combined effects of gap junctions, CP49‐intermediate filament and periaxin‐mediated cytoskeleton synergistically regulate the interdigitation structures and metabolism of lens inner fiber cells, which modulate lens transparency, homeostasis and cataractogenesis.Support or Funding InformationSupported by EY013849 grant from the National Eye Institute