bluuebunny/crossref_metadata_2025_split huggingface dataset:
Akt/PI3K signaling sustains the chronic alcoholic effects on the heart (862.6)
Authors: Umoh Nsini , Jeffress Miara , Haddad Georges 
Published: June 2021

Cardiovascular diseases are the leading causes of increased mortality and morbidity rates. Specifically, alcohol induced cardiomyopathy is a preventable dysfunction that is associated with premature deaths. High alcohol (HA) intake has been shown to negatively impact the heart function into having reduced contractility with dilated cardiomyopathy. However, low alcohol (LA) intake has been clinically shown to be beneficial. Prior studies in our lab have linked the Akt/PI3K pathway to cardiac dysfunction. In this study, we investigate the role of Akt activity (western blot) that contributes to changes in cardiac contraction and calcium mobilization (Ionoptix), cell survival (Cell Viability Assay), caspase activity (caspase 3/7 assay) and oxidative stress associated with chronic LA (0.02%) and HA (0.45%) consumption using Lieber‐DeCarli alcohol diet (4 months). Our results demonstrate that rats on a LA liquid diet experienced decreased caspase activity and increased calcium mobilization and cellular/sarcomere contraction. However, the above Akt‐mediated effects are diminished with rats on a HA diet. Our results also show that the inhibition of NFkB causes further aggravation of alcohol‐induced cardiomyopathy. Our data suggests that Akt signaling plays an important role in supporting the beneficial effects of LA which is diminished with HA exposure having detrimental effects on cardiac function.Grant Funding Source: This work was supported in part by grants NIH/NIAAA/1R15AAA019816‐01A1, and 2G12 RR003048 RCMI/NCRR/
Cardiac mitochondrial disruption in response to hypothermia and rewarming (864.1)
Authors: Schaible Niccole , Han Young Soo , Arteaga Grace , Tveita Torkjel , Sieck Gary 
Published: June 2021

Recovery from accidental hypothermia followed by rewarming (H/R) is often unsuccessful due to heart failure. Although the causes for H/R‐induced heart failure remain elusive, studies at the cellular level suggest alterations in both cytoplasmic and mitochondrial Ca2+ regulation. We hypothesize that H/R is associated with mitochondrial Ca2+ overload, which leads to: 1) excessive reactive oxygen species (ROS) generation, 2) mitochondrial membrane depolarization, and 3) mitochondrial cytochrome c release. To test this hypothesis, isolated cardiomyocytes from adult male Sprague‐Dawley rats were subjected to an in vitro H/R protocol (1 h cooling to 15oC held for 30 min followed by 1 h rewarming to 37oC). Cytoplasmic (CM‐H2DCFDA fluorescence) and mitochondrial (MitoSOX fluorescence) ROS generation increased during cooling and remained elevated throughout the H/R protocol. Mitochondrial membrane potential (TMRM fluorescence) depolarized during rewarming suggesting mitochondrial permeability transition pore opening. After rewarming, cytochrome c content (Western blot) in cytoplasmic to mitochondrial fractions increased indicating release. These results suggest that Ca2+ overload associated with H/R induces ROS generation leading to mitochondrial disruption.Grant Funding Source: Supported by NIH Grant 5T32HL105355‐02 (GCS)
Mutation of Kvβ2 active site attenuates cardiac injury: role of repolarization reserve (864.2)
Authors: Chapalamadugu Kalyan , Panguluri Siva , Tur Jared , Tipparaju Srinivas 
Published: June 2021

Cardiac Kvβ2 subunit alters gating and expression of potassium channels. However, the physiological significance remains unknown. Therefore, we evaluated the role of Kvβ2 in cardiac injury. We used 14 week male wild type (Wt) or mutant Kvβ2:PM (active site mutant; Y90F) mice, infused with saline or isoproterenol (Iso, 30mg/kg; bw/day) for 14 days. Iso treatment resulted in cardiac hypertrophy in both mice as noted by histomorphological analysis. Echocardiographic assessment revealed significant decrease (p <0.05) in EF% and FS% upon Iso stress in both Wt (71.1±1.7 vs. 55.9±1.7; 40±1.4 vs. 29.0±1.2) and PM (66.3±2.7 vs. 57 ± 2.8; 36.2 ± 2.0 vs. 30.0 ± 1.9), mice. Ex vivo recording of action potential durations (APD) showed repolarization depletion in Wt saline vs. Iso infused mouse hearts at APD60 (11.9±0.7 vs. 31.6±1.1) and APD80, 43.1 ± 1.9 vs. 51.9 ± 1.9), respectively. However, in PM mice Iso did not induce APD prolongation (APD60, 19.7±1.1 vs. 24.2±1.8 or APD80, 49.8±1.8 vs. 49.3±2.0) suggesting protection. Similarly, ECG analysis showed QTc interval (59.7±2.4 vs. 68.6±2.0, ms) change in Wt saline vs. Wt Iso groups, which is not observed in PM mice (70±1.7 vs. 68.9±0.6). Expression of key ion channels (Kv4.2, Kv1.4 and Kv1.5) was unaltered in PM mice, but significantly depleted in Wt with Iso treatment. Together, Kvβ2 active site mutant restores repolarization reserves and offers protection against cardiac injury.Grant Funding Source: HL102171
Cellular and molecular characterization of type II diabetic bladder dysfunction (865.12)
Authors: Klee Nicole , Moreland Robert 
Published: June 2021

In a rat model of Type II diabetes (T2D), cellular and molecular alterations in muscarinic and purinergic receptor stimulation and associated downstream signaling molecules in bladder smooth muscle was examined over time. T2D was induced in Sprague Dawley rats using the combination of a high fat diet and low dose streptozotocin (HFD/STZ). A 40% HFD was initiated in 14 week old rats; after one month, rats were administered two low doses of STZ (30 mg/kg) one week apart. This model results in obesity, hyperglycemia, insulin resistance, and has been shown to induce diabetic bladder dysfunction (DBD); although this model has rarely been used to characterize DBD or determine mechanistic changes in the regulation of the bladder. DBD is a common complication of T2D, a non‐life threatening complication of diabetes that has a significant negative impact on quality of life. Bladder smooth muscle was isolated and isometric force was recorded in response to the cumulative and non‐cumulative addition of carbachol, bethanechol, ATP, and KCl in both control and HFD/STZ rats. Urodynamic profile, body weight, and glucose measurements were recorded over time pre and post STZ injections. The results of these studies can then be used to determine the efficacy of current and novel therapeutic interventions aimed specifically at the site of dysfunction induced by T2D as well as potential sites of dysfunction affected by aging.Grant Funding Source: NIH DK 85734
Smooth muscle‐targeted overexpression of peroxisome proliferator‐activated receptor gamma disrupts vascular wall structure and function (866.4)
Authors: Sutliff Roy , Kleinhenz Jennifer , Murphy Tamara , Pokutta‐Paskaleva Anastassia , Gleason Rudolph , Lyle Alicia , Taylor W. , Yang Qinglin , Hart C. 
Published: June 2021

Objective: To explore the role of PPARγ in vascular regulation, smooth muscle VP16‐PPARγ‐overexpressing mice were subjected to studies of systemic vascular function, biomechanical testing, histological analysis, and molecular characterization. Methods: Mice with a flox‐controlled VP16‐PPARγ gene were crossed with mice containing a tamoxifen‐inducible Cre recombinase driven by a smooth muscle myosin heavy chain promoter. All mice received tamoxifen injections at 6 weeks of age. Experiments were performed at 10‐16 weeks of age. Results: Compared to littermate controls, transgenic mice displayed: 1) aortic dilation (by histology, echocardiography, and microCT), 2) increased aortic compliance, 3) reduced blood pressure, 4) 80% reduction in aortic ring contractile forces in response to KCl or phenylephrine, 5) lipid accumulation in the aortic media (Oil Red O staining), and 6) reduction in aortic contractile markers and extra‐cellular matrix components with increased expression of adipose markers and selected mitochondrial proteins (by qPCR).Conclusion: These results demonstrate that targeted overexpression of activated PPARγ in smooth muscle disrupts vascular wall structure and function in part by driving medial smooth muscle towards an adipocyte phenotype.Grant Funding Source: Supported by grants from NIH (R01 HL102167) and VA (Merit Review Award 1I01BX001910)
Less intimal thickening and impaired elastic fiber formation in the chicken ductus arteriosus (867.14)
Authors: Omori Eriko , Akike Toru , Kajimura Ichige , Minamisawa Susumu , Goda Nobuhito 
Published: June 2021

Object: We investigate the vascular remodeling of the chick ductus arteriosus in order to investigate the new mechanism of its closure.. Experiments and Results: We isolated the DAs from chicken embryos and neonates. Histological analysis with Elastica van‐Gieson staining demonstrated that the sparse and fragmented elastic fibers in the medium from embryo day 16, and impairment became more apparent with development. Intimal cushion formation was not clearly observed even after external hatching. Real‐time PCR analysis revealed that the expression levels of elastin and lysyl oxidase mRNAs were significantly lower in the DA than in the aorta. Genes related with the PGE2‐EP4 signal pathway were not predominantly expressed in the chicken DA.Conclusion: Internal cushion formation was less prominent in the chicken DA than in the mammalian DA. On the other hand, elastic fiber formation was severely impaired in the chicken DA, which was unlikely due to the PGE2‐EP4 signal pathway.
GPER activation ameliorates vascular remodeling in salt‐sensitive mRen2.Lewis rats (867.7)
Authors: Lindsey Sarah , Liu Liu , Chappell Mark 
Published: June 2021

The mRen2.Lewis female rat is an estrogen‐ and salt‐sensitive model of hypertension which may reflect the higher pressure and salt sensitivity associated with menopause. In salt‐loaded mRen2.Lewis, activation of the novel estrogen receptor GPER reduces renal hypertrophy, proteinuria, and oxidative stress but not blood pressure (Lindsey et al. 2011). The current study hypothesized that vascular remodeling is also improved by GPER activation in the absence of changes in blood pressure. Intact mRen2.Lewis females were fed a normal (0.5% Na+) or high salt diet (4% Na+) for 10 weeks and treated with vehicle or the selective GPER agonist G‐1 for the last two weeks of the study. Systolic blood pressure was measured by tail cuff plethysmography, and aortic sections were mounted on a wire myograph or formalin‐fixed for histological analysis. Systolic blood pressure increased with the high salt diet (137 ± 2 mmHg, n=7 to 224 ± 8, n=9; P<0.001) and remained unchanged with G‐1 (216 ± 4, n=9; P>0.05). While aortic reactivity to phenylephrine and acetylcholine were not different between groups (P>0.05), chronic G‐1 treatment reduced vasoconstriction to angiotensin II (P<0.05) and enhanced G‐1 vasorelaxation ex vivo (P<0.01) in both endothelium‐intact and denuded aortic rings. Analysis of aortic sections revealed that while the high salt diet significantly increased the media to lumen ratio (0.43 ± 0.02, n=6 vs. 0.83 ± 0.05, n=7; P<0.001), two‐week G‐1 treatment partially reversed the salt effect (0.62 ± 0.02, n=6, P<0.005). We conclude that GPER exerts vascular protective actions in the aorta of salt‐loaded mRen2.Lewis females independently of blood pressure. The anti‐remodeling actions of this novel estrogen receptor may be effective in postmenopausal cardiovascular disease by targeting the vascular renin‐angiotensin system.Grant Funding Source: Supported by NIH (HL56973, HL51952, HL103974) and the American Heart Association (25515E, 3080005)
Overexpression of miRNA‐195 induced by hyperthyroidism is attenuated by the AT1 receptor blockage (868.6)
Authors: Diniz Gabriela , Barreto‐Chaves Maria Luiza 
Published: June 2021

Introduction: miRNA‐195 is increased during cardiac hypertrophy, and it´s overexpression is sufficient to drive cardiac growth. We demonstrated that the AT1 receptor (AT1R) participates of the thyroid hormone (TH)‐induced cardiac hypertrophy. However, the potential modulation of the miRNA‐195 in TH‐mediated cardiac growth, as well as the possible contribution of the AT1R in this event is unknown.Objective: The aim of this study was to investigate the cardiac miRNA‐195 levels in TH‐induced cardiac hypertrophy, as well as the potential role of the AT1R in this response.Methods: The hyperthyroidism was induced by injections of T4 for 14 days. The T4 group was subdivided into two groups: T4 and T4 plus Losartan (an AT1R blocker). Cardiac hypertrophy was assessed by heart weight (HW) to tibia length (TL) ratio and by the ANF and skeletal‐alpha actin gene expression. The analysis of the miRNA levels was assessed by miRNA Stem Loop RT‐PCR. Data are presented as mean±SD (n=5).Results: The hyperthyroid group presented cardiac hypertrophy, as evaluated by the higher HW to TL length ratio, as well as by the increased ANF and skeletal‐alpha actin mRNA levels. However, the AT1R blocker prevented the cardiac hypertrophy induced by T4. In addition, the cardiac growth in response to TH was accompanied by higher cardiac levels of miRNA‐195 (4.9±0.7, P<0.01 vs control), which were attenuated by the use of the AT1R blocker (2.1±0.5, P<0.01 vs T4).Conclusions: These results evidence for the first time that T4‐induced cardiac hypertrophy is accompanied by a cardiac overexpression of miRNA‐195, and that the AT1R participates at least in part of this response.Grant Funding Source: Supported by FAPESP (Foundation for the Support of Research in the State of Sao Paulo) and by CNPq.
Cardiac specific TIMP‐4 dictates cardiomyocyte contractility through Serca‐2a in cardiac dysfunction: a novel mechanism (868.7)
Authors: Chaturvedi Pankaj , Metreveli Naira , Tyagi Suresh 
Published: June 2021

Although previous studies show MMP9 (Matrix Metalloprotease 9) dysregulation in cardiac disorders, the mechanisms how an MMP9 modulator (TIMP4‐Tissue Inhibitor of Matrix Metalloprotease 4) regulates contractility and regeneration remain elusive. Providing an insight into this mechanism, we hypothesize that TIMP4 regulates cardiomyocyte contractility by regulating the expression of Serca‐2a (Sarcoplasmic Reticulum Calcium ATPase) through microRNAs. To check this hypothesis, we overexpressed TIMP4 in cardiomyocytes along with its inhibition through siRNA, to elucidate the contractility profiles and establish regulatory effects of TIMP4. We checked the expression of serca‐2a and microRNA 122 with Western, RT‐PCR, qRT‐PCR. DesRed2 plasmid carrying the TIMP4 gene was used to overexpress TIMP4 in mouse cardiomyocytes while GFP plasmid was used as control to standardize transfections. Contractility measurements were executed by ION OPTIX instrument and transfection studies were done by confocal microscopy. The expression studies of TIMP4 were performed by Western, RT‐PCR, qRT‐PCR and additionally confirmed in HL‐1 cardiomyocyte cell line. We found increased contractility with increase in the amplitude and peak height with TIMP4 overexpression while with siRNA, the results were reversed. Intrestingly, we found increased expression of serca‐2a along with downregulation of microRNA 122. The data suggested a novel regulatory effect of TIMP4 on contractile function by regulating serca‐2a through microRNA 122.Grant Funding Source: NIH grant HL‐74185 and HL‐108621
Stimulation of mitochondrial superoxide in lung epithelial cells using a novel stretching device (869.5)
Authors: Rapalo Gabriel , Roan Esra , Schwingshakl Andreas , Eckstein Eugene , Waters Christopher 
Published: June 2021

Mechanical ventilation of patients with acute lung injury can cause further damage to the lung epithelium, leading to ventilator‐associated lung injury. We and others have previously demonstrated that cyclic stretch of bronchial and alveolar epithelial cells stimulates increased production of reactive oxygen species (ROS) and other proinflammatory cytokines, but the mechanism is not completely understood. To investigate, we designed a motor‐driven device to apply linear strains up to 20% on cells grown on an elastic substrate while imaging under a confocal microscope. We hypothesized that distention of the lung epithelium triggers an oxidative stress response of mitochondrial superoxide through deformation of the mitochondria and actin filaments. Cultures of an immortalized human airway epithelial cell line (16HBE) and human alveolar type II cell line (A549) were tonically stretched while the production of mitochondrial superoxide was measured using MitoSox. Stretch in 16HBE cells caused a significant increase in production of superoxide, while treatment with Tiron or Cytochalasin D both prevented the stretch‐induced increase in superoxide. A549 cells did not show a significant increase in production of superoxide compared to treatment with the inhibitors. A single tonic deformation of the mitochondria via actin filaments directly stimulated the release of superoxide.Grant Funding Source: Supported by NIH grant HL094366 (CMW)
Expression of BMP‐2 in the pulmonary neuroepithelial body microenvironment (869.7)
Authors: Verckist Line , Lembrechts Robrecht , Schnorbusch Kathy , Pintelon Isabel , Timmermans Jean‐Pierre , Brouns Inge , Adriaensen Dirk 
Published: June 2021

Recently, members of the bone morphogenetic protein (BMP) family, in particular BMP‐2, have been reported to promote adult lung tissue repair after injury. Following severe experimental intrapulmonary airway epithelial damage, the neuroepithelial body (NEB) microenvironment (ME) has been shown to be involved in epithelial regeneration, and today may be regarded as an airway stem cell niche. The NEB ME consists of highly innervated groups of pulmonary neuroepithelial endocrine cells, which are specifically covered by Clara‐like cells with supposed stem cell characteristics.Here we studied the expression of BMP‐2 in the NEB ME of healthy postnatal mouse lungs. After collection of ‘NEB sample’ by selective isolation of GFP‐fluorescent NEBs via laser microdissection from frozen sections of GAD67‐GFP mouse lungs, (q)RT‐PCR revealed a significantly higher expression of BMP‐2 in the NEB ME, compared to control airway epithelium. Localization of the BMP‐2 protein in postnatal mouse lungs by multiple immunofluorescence, revealed that BMP‐2 was expressed by vagal sensory nerve fiber endings that selectively contact NEB cells.The presented data reveal a strong expression of BMP‐2 in the NEB ME and strengthen the suggestion of an important role in postnatal airway epithelial repair after injury.Grants: FWO (G.0589.11), Hercules Foundation (AUAH‐09‐001); UA (GOA BOF 2007)
IgE and H. pylori titers in severe asthmatic subjects versus controls: antigen hyperreactivity or etiology? (870.1)
Authors: Varanasi Laalasa , Lankala Shreya , Quinn Tim , Herndon Betty 
Published: June 2021

Nearly 25 million Americans are asthmatic, and several triggers have been implicated for producing symptoms. Gastroesophageal reflux (GER), often caused by H. pylori, is common and may trigger asthma exacerbations. The hyperreactivity to antigens in atopic asthma may have effects on H. pylori‐associated GER. The rationale for this study was to determine, in a population of asthmatics and controls, if the H. pylori serum titer is related to elevated IgE (atopy). Sera from 58 severe asthma subjects and 24 control sera were used for IgE and H. pylori specific ELISAs to test for titer based on a 450 nm read of 2.000 or greater (high) or a read below 0.25 (low). Asthmatic IgE samples were 44.83% high, 12.06% low while controls were 8.3% high and 16.7% low. Asthmatic sera H. pylori titers, read on the same scoring system, showed 16.07% high and 26.7% low. Control sera had no H. pylori high values and 61.9% low. 77.8% of the asthmatic subjects with high serum H. pylori titers had high serum IgE titers also. Only 11.1% of the asthmatic subjects with low H. pylori titers also had low IgE. No steroid use data were available for either group. We conclude that, in this patient population diagnosed as severe asthmatics by our hospital pulmonology dept, H. pylori is significantly more prevalent than in controls, although total IgE in asthmatics appears higher than H. pylori‐specific IgE.Grant Funding Source: Supported by Student Sarah Morrison grant to LV
Visualization of dynamic airway bronchoconstriction in live rats (870.6)
Authors: Phung Thien‐Khoi , Sinclair Scott , Makena Patrudu , Molthen Robert , Waters Christopher 
Published: June 2021

Airway hyperresponsiveness severely limits gas exchange in patients with asthma. Imaging studies have shown that bronchoconstriction causes patchy patterns of ventilation defects throughout the lungs, and computational models have predicted that these regions are due to constriction of small airways. Since these imaging approaches are limited in their ability to capture dynamic changes in small airways, we utilized tantalum dust and microfocal X‐ray imaging of rat lungs to obtain dynamic images of airways in an intact animal model. The flexiVent system was used to simultaneously measure airway resistance. Custom software was used to track changes in airway diameters up to 13 generations (~0.3 mm to 3 mm in diameter). The objective of the study was to identify the size and location of airways with changes in diameter during bronchoconstriction in response to methacholine. In contrast with the model predictions, we observed significantly greater percent constriction in larger airways in response to methacholine challenge. Although there was a dose‐dependent increase in airway resistance, the percent change in airway diameters was similar for increasing doses. Paradoxically, a deep inspiration following methacholine caused greater percent constriction in smaller airways. These measurements allow us to directly quantify dynamic changes in airways during bronchoconstriction.Grant Funding Source: Supported by NIH HL094366 (CMW) and APS UGSRF (TNP)
Loss of M2 and M3 muscarinic receptor function in double mutant mice eliminates ovalbumin‐induced airway hyperresponsiveness (870.7)
Authors: Fisher John , Vincent Sandra , Wannas Paul , Wess Jurgen 
Published: June 2021

Mutant murine models lacking specific muscarinic receptor (MR) subtypes are a primary tool to explore MR biology in health and disease, due to the lack of selective antagonists. Since both M2R and M3R subtypes are involved in the vagal control of airway responsiveness (AR; FASEB J 18:711,2004), we examined the impact of combined loss of M2R and M3R function on the development of AHR in M2R‐/‐/M3R‐/‐ double mutant mice. AR was assessed in 12 mutant mice divided into an ovalbumin (OVA) sensitization group (n=6; OVA‐Alum adjuvant i.p. day 0 and 7 plus aerosol exposure days14‐16) and an Alum adjuvant control group (n=6; Alum). Since M2R‐/‐/M3R‐/‐ double mutants show no cholinergic contractile responses, we performed a 5‐hydroxytryptamine (5‐HT) i.v. dose‐response challenge (5‐100 ug/kg) for respiratory system resistance (Rrs) to assess AR and bronchioalveolar lavage (BAL) to assess inflammatory cells. The Rrs response was not different between groups (max increase OVA 339%+32 sem vs Alum 301%+28; p>0.05), although the BAL eosinophil count was significantly greater in the OVA group (25% + 5) compared to the Alum (0.1% + 0.08). Our results suggest that M2R/M3R functions are critically involved in the development of OVA‐induced AHR.Grant Funding Source: Supported by Canadian Institutes for Health Research (MOP81211), Intramural Research Pgm NIDDKD, NIH