bluuebunny/crossref_metadata_2025_split huggingface dataset:
Central and Peripheral Respiratory Disturbances in a Mice Model of Parkinson's Disease
Authors: Oliveira Luiz M. , Oliveira Maria A. , Moriya Henrique T. , Moreira Thiago S. , Takakura Ana C. 
Published: June 2021

Parkinson's disease (PD) is a neurodegenerative motor disorder characterized by dopaminergic deficits in the brain. PD patients may experience shortness of breath, dyspnea and breathing difficulty. Breathing abnormalities have been recognized as a cause of morbidity and mortality of PD patients. It is well known that PD patients have a predisposition to develop pneumonia, embolism and allergic reactions compared to general population. However, it's not clear if an animal model of PD could develop lung properties changes. The aim of the present study is to confirm the role of neurodegenerative processes in brainstem regions involved in breathing control and to investigate lung properties in a mouse model of PD. Experiments were performed in adult male C57BL/6 mice (20–25 g, N = 14). The animals received bilateral injection of 6‐hydroxydopamine hydrochloride (6‐OHDA; 10 μg/μL; 0.5 μL) or vehicle into the striatum. The ventilatory parameters were assessed by whole body plethysmograph and measurements of respiratory mechanics by a mouse ventilator (flexiVent) 40 days after PD induction. 6‐OHDA reduced the number of tyrosine hydroxilase (TH+) neurons in the SNpc 40 days after the toxin injection. No changes in TH+ were observed in C1 and Locus coeruleus regions in PD mice. We also noticed a reduction in the immunoreactivity of neurokinin‐1 receptors (NK1R) in the pre‐Bötzinger complex (preBötC) and in the number of Phox2b neurons in the retrotrapezoid nucleus (RTN). Physiological experiments were conducted in the same animals. Resting respiratory frequency (fR) in PD animals was reduced (156.3 ± 3.4 vs. control: 176.1 ± 3.5 breaths/min) leading to an increase of expiratory time (TE) (0.36 ± 0.02 vs. control: 0.28 ± 0.03 ms). In respect to mechanical properties, PD animals with preserved thorax elicited an increase in airway resistance (0.33 ± 0.02 vs. control: 0.27 ± 0.01 cmH2O.s/ml) and elastance (31.3 ± 2.1 vs. control: 25.3 ± 0.6 cmH2O/ml, p<0.019). However, after open the thorax, PD animals did not show changes in airway resistance, but still have an increase in elastance (30.8 ± 2.1 vs. control: 24.0 ± 1.4 cmH2O/ml, p<0.017), indicating that the ribcage could be stiffened in PD. PD animals presented collagen deposition in alveolar septa (18.3 ± 1.5 vs. control: 12.5 ± 1.4 %). Our data showed that PD animals presented neurodegeneration in respiratory brainstem areas and a disruption of lung properties, suggesting that central and peripheral deficiencies can contribute to the respiratory changes observed in this model.Support or Funding InformationFAPESP, CNPq, CAPES/PROEXThis abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Cystic Fibrosis Transmembrane Conductance Regulator Regulates Pannexin 1 Channel Opening for Acidosis‐induced ATP Release from Cardiomyocytes
Authors: wang yongshun , Ballard Heather Janet 
Published: June 2021

ATP is released in the heart under a variety of conditions, including hypoxia, ischaemia and catecholamine stimulation. Under physiological conditions, extracellular ATP, and its breakdown product, adenosine, contribute to local vasodilation and regulation of coronary blood flow. We investigated the mechanism of ATP release in cardiomyocytes isolated from adult rat heart.Treatment with lactic acid produced pH depression and enhanced ATP release from cardiomyocytes. On the other hand, simulated ischaemia (metabolic inhibition plus anoxia) lowered ATP release. The acidosis‐induced ATP release was abolished by the specific CFTR inhibitor, CFTRinh‐172, CFTR pore blocker, GlyH‐101, or CFTR siRNA, suggesting that CFTR was involved. Forskolin and IBMX, agents that activate CFTR by elevating the intracellular cAMP, also increased ATP release, confirming the role of CFTR. However, blockade of Pannexin1 channels by Fast Green FCF, Brilliant Blue FCF, or pannexin1 siRNA, attenuated the ATP release during acidosis or forskolin treatment, and further lowered the ATP release during simulated ischaemia, suggesting that Pannexin1 functions as the ATP release channel. Immunofluorescence imaging suggested that CFTR and Pannexin1 were not co‐localized. Inhibition of either the Na+/H+ exchanger (NHE) with amiloride or the Na+/Ca2+ exchanger (NCX) with SN6 or KB‐R7943 abolished acidosis‐induced ATP release. FAK inhibitor 14, FAK autophosphorylation inhibitor, can attenuate the forskolin or lactic‐acid‐stimulated ATP release. Furthermore, forskolin or lactic‐acid‐stimulated ATP release was abolished by bicarbonate free medium or caspase inhibitor. Thus, we have demonstrated that the acidosis‐induced ATP release was involved in calcium induced CFTR open. The cyclic AMP, which activates mitochondrial PKA, is generated within mitochondria by the bicarbonate‐regulated soluble adenylyl cyclase (sAC). Hence, we propose that the CFTR Cl channel opens during acidosis, allowing the movement of bicarbonate into the cell, which activate the HCO3‐sAC‐cAMP‐PKA (mito‐sAC) signaling cascade and indirectly modulates Pannexin1 gating by activation of caspase.This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Glypican‐1 Mediates Endothelial Hyper‐permeability in a Model of Acute Heart Failure
Authors: Chignalia Andreia , Isbatan Ayman , Patel Milan , Borlaug Barry , Dull Randal 
Published: June 2021

Accumulating evidence indicates that the lungs are active participants in the pathogenesis of heart failure (HF). Increases in left ventricular end diastolic pressure (LVEDP) leads to elevated pulmonary capillary pressure (PCP) that causes fluid filtration resulting in dyspnea and, ultimately, frank pulmonary edema (PE). However, the severity of dyspnea does not directly relate to the increase in PCP indicating that the clinical manifestation of HF cannot be solely explained by changes in Starling forces. Acute increases in PCP activate glycocalyx‐dependent signaling (endothelial mechanotransduction) that result in oxidative stress, eNOS activation and endothelial hyper‐permeability. Herein we sought to investigate if glypican‐1, a component of the glycocalyx, contributes to pressure‐dependent hyper‐permeability and PE in a model of acute HF. The isolated perfused lung preparation was used to simulate acute HF in male CD‐1 (wild type, WT) and glypican‐1 knockout (Gpc‐1 KO) mice (6 weeks old). Briefly, mice were anesthetized with isoflurane, tracheostomized and mechanically ventilated. Pulmonary artery and left atria were cannulated and in‐line pressure transducers recorded arterial and left atrial pressure; lungs were perfused at 2 mL/min with a Krebs‐Ringer 3% BSA buffer. Control experiments were done setting left atria pressure (PLA) at 3 cm H2O for 10 minutes; acute heart failure was simulated by setting PLA at 10 cm H2O for 10 minutes. Lung edema was assessed by lung wet‐to‐dry ratio; reactive oxygen species (ROS) production and eNOS activation were assessed as indices of mechanotransduction activation by lucigenin enhanced chemiluminescence and immunoblotting, respectively. NADPH oxidase activity was measured by dihydroethidium fluorescence in isolated membrane‐fracions. WT and Gpc‐1 KO mice had similar increase in pulmonary artery pressure (from 8 to 10 mmHg). Deletion of glypican‐1 protected mice from pressure‐induced PE (wet‐to dry ratio [high and low pressure, respectfully] in WT: 7.3±0.3 vs 4.9±0.3 and in Gpc‐1 KO: 4.8±0.3 vs 4.8±0.2), prevented pressure‐dependen increase in NADPH oxidase activity (15% increase in WT) and in ROS production (80% increase in WT). Moreover, while WT mice showed increased eNOS activation (2‐fold) during acute HF, Gpc‐1 KO mice showed reduced eNOS activation (0.5 fold) indicating that Gpc‐1 is a determinant for mechanotransduction signaling. Taken together, these results suggest that Gpc‐1 activation by pressure leads to endothelial hyper‐permeability due to ROS and NO‐dependent pathways and contributes to PE in an in situ model of acute HF.This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
The Acute Inotropic Effect of the Uremic Metabolite, Trimethylamine‐N‐Oxide (TMAO), on Human Cardiac Muscle
Authors: Oakley Carlee I. , Sanborn David , Rafie Nikita , Hendrix Matt , Stubbs Jason R. , Shawgo Tilitha , Daon Emmanuel , Zorn George , Wacker Michael J. 
Published: June 2021

BackgroundCardiovascular disease is endemic among patients with chronic kidney disease (CKD). Growing evidence suggests the gut microbiome plays an obligatory role in cardiovascular pathogenesis. TMAO is a downstream byproduct of intestinal microbe metabolism of phosphatidylcholine and L‐carnitine that may directly promote atherosclerosis formation. Since clearance of this uremic metabolite is dependent on urinary excretion, plasma levels of TMAO increase with decrements in kidney function. Association studies have linked plasma levels of TMAO to adverse cardiovascular outcomes in patients with renal dysfunction; however, to our knowledge, we are the first to investigate whether TMAO alone has any direct effect on cardiac contractility. In prior studies, we found TMAO to acutely increase contractile force in mouse hearts ex vivo. The objective of the current investigation was to determine if our findings translated to human heart tissue.MethodsHuman right atrial appendage biopsy tissue was retrieved during cardiopulmonary bypass procedures, prior to cannula placement. The cardiac muscle samples were attached to a force transducer and bubbled with oxygen inside an organ bath. Changes in contractility were measured after treatment with TMAO or vehicle (Ringer's solution).ResultsIn our previous studies using mouse hearts, we found acute treatment with TMAO in the organ bath increased average contraction amplitude 20% and 41% at 300 μM and 3000 μM, respectively (P < 0.05, n = 6–7 animals). Langendorff reverse perfusion of hearts with 300 μM TMAO generated an even greater response than incubation and increased isometric force 32% (P < 0.05, n = 2–3). Consistent with what we observed in the animal model, incubation of human atrial muscle tissue with TMAO at 3,000 μM increased isometric tension 31% compared to vehicle (P < 0.05, n = 4–5).ConclusionsTMAO, at pathological concentrations, directly increases cardiac contractility in both animal and human hearts. Initially, this inotropic effect may be beneficial or adaptive during CKD; however, chronic increases in cardiac contractility can promote cardiac remodeling and left ventricular hypertrophy. Further in vivo studies are needed to determine how chronic exposure to TMAO may contribute to cardiac pathology in CKD and to examine if TMAO represents a therapeutic target for reducing cardiovascular mortality in CKD patients.This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
The Role Of P62 On Chronic Oxidative Stress‐Induced Myocytes Ca handling
Authors: Koh Yeojung , Jung Yooyeon , Lee Kwangjun , Salazar Gloria , Hwang Hyun Seok 
Published: June 2021

IntroductionRecent studies have shown that the activity of autophagy impairs, and the accumulation of p62 protein, autophagy substrate, in the heart observes in heart failure patients and mouse models of cardiomyopathy. Accumulations of p62 protein are known to activate the intrinsic cellular stress. Abnormal Ca release is partly responsible for oxidative stress‐induced contractile dysfunction of myocytes in ischemic heart disease. Myocytes Ca release is controlled by a function of sarcoplasmic reticulum (SR) Ca store. However, the role of p62 protein on myocytes Ca regulation in the ischemic heart is not clear.PurposeTo investigate the role of p62 on SR Ca regulation in myocytes isolated from mice with the Isoproterenol‐induced myocardial injury.MethodsTo test our hypothesis, both wild‐type (WT) and p62 knockout (KO) mice were used at 10–12 weeks of age. Myocytes isolated from WT and p62 KO mice (n=3 per group) injected with 200 mg/kg Isoproterenol (ISO; beta agonist, twice per day) for 0 (Base), 5 days, and 10 days. SR Ca handling and contractility measured in field‐stimulated single myocytes loaded with fluorescent Ca indicators (Fura‐2AM; cytosolic Ca loading). Amplitudes of caffeine (10 mM, 5 sec)‐induced Ca transients used as estimates of SR Ca store. Sets of heart from WT and p62 mice were processed for western blot (n=3 per group).ResultsThe p62‐deficient myocytes had no difference of myocytes contractility, and SR Ca handling at the baseline compared to WT myocytes (n=35–45 cells per group). After acute ISO exposure (1μM for 1 min), WT myocytes increased systolic Ca release whereas p62‐deficient myocytes did not. An exposure of a submaximal oxidative stress (1μM; H2O2) in p62‐deficient myocytes, however, increased myocytes contractility and the fraction of Ca released from the SR during each beat (fractional Ca release; systolic Ca release over SR Ca store) after acute ISO stimulation (p<0.05). In WT mice injected with ISO for 5 days and 10 days, myocytes had a biphasic effect on myocytes contractility and fractional Ca release (n=15–45 cells per group, p<0.05). Interestingly, in p62‐deficient myocytes further increased myocytes contractility and fractional Ca release (Figure) on chronic ISO injections from 5 days to 10 days. WT mice hearts with chronic exposure to ISO for 10 days increased p62 protein expressions and suppressed the conversion of LC3 I to LC3 II.ConclusionTaken together, our results suggest that accumulations of p62 protein may directly cause SR Ca defects via beta‐adrenergic signaling in myocytes under chronic myocardial injury.This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Antiarrhythmic Activity of NMDA Receptor Antagonists in Humans Versus Animal Models
Authors: Elnakish Mohammad T. , Repas Steven J. , Whitson Bryan A. , Mohler Peter J. , Janssen Paul M.L. 
Published: June 2021

Understanding of cardiac ion channels as well as inventive ways to intend compound screening will allow a novel expectation for imminent discovery of antiarrhythmic remedies. In this regard, N‐methyl D‐aspartate receptor (NMDAR) antagonists, such as memantine, which are clinically approved for the treatment of Alzheimer's disease (AD), Huntington's disease, and dementia have displayed promising protective effects against cardiac arrhythmia in several animal models. However, our current data revealed that maximal ex‐vivo β‐adrenergic stimulation of the right ventricular (RV) papillary muscles, but not in‐vivo ECG analysis of thyroxine‐treated mice, exhibited arrhythmia in undoubtedly higher number (~ 62 %) compared to the control, and this even reached a greater level (~ 73 %) following memantine treatment. Transformation of outcomes acquired in animal models to human pathophysiology is frequently hampered by species‐dependent dissimilarities. Thus, it is critical to keep investigating the ex‐vivo effects of prospective attractive drugs on initiated arrhythmia and contractility in the ventricular human myocardium to confirm data that was exclusively acquired from animal models. Interestingly, our preliminary data illustrate that arrhythmia elicited by 100 nmol/L isoproterenol and 0.5 mmol/L caffeine in isolated RV muscles of non‐failing human hearts is inhibited by memantine in a concentration‐dependent manner with a full reserve at 50 μM. However, the exact IC50, mechanism, possibility of pro‐arrhythmia at a higher concentration as well as its impact on the contractile profile of cardiac muscle, which represents an important complementary safety measure to therapeutic efficacy is currently unknown. We have previously reported that zacopride; a moderate IK1 channel activator shows promising antiarrhythmic effects against generated arrhythmia in human ventricular myocardium using the same protocol. This opens the door for further investigation of the possible correlation between NMDAR‐IK1 channel‐Ca2+ signaling pathways in ventricular tachycardia, which is the leading cause of sudden arrhythmic death in the U.S.Support or Funding InformationThis study was supported by American Heart Association Great Rivers Affiliate Post‐doctoral Fellowship 16POST27760155 to M.T. Elnakish and National Heart, Lung, and Blood Institute Grant R01 HL‐113084 to P. M. L. Janssen.This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
The Structure‐function Remodeling and Therapeutic Effect of Tongxinluo Capsule in Rabbit Hearts of Myocardial Infarction
Authors: LI LI , Yunlong Huo 
Published: June 2021

ObjectiveAnimal models are important to study basic mechanism of ischemic heart failure (HF). The objective of the study was to create rabbit models of myocardial infarction to investigate the structure‐function remodeling of the left ventricle (LV) and coronary arterial trees and the therapeutic effects of Tongxinluo Capsule.MethodNew Zealand white rabbits were randomly divided into sham group, model group and therapeutic group. The rabbit models were created through multiple coronary artery ligations. Echocardiographic, Micro‐CT and histological measurements were performed at postoperative 6 weeks and postoperative 12 weeks, respectively.ResultEchocardiographic measurements of the model group showed an approximately monotonic slope of ejection fraction and fractional shortening from 73% and 40% to 58% and 28% as well as persistent enlargement of LV cavity and slight mitral regurgitation at postoperative 12 weeks. Measurements of micro‐CT and histology revealed that coronary vascular sparseness and cardiac fibrosis related to inflammation occurred concurrently in adjacent zone of MI at postoperative 12 weeks although there was compensatory vascular growth at postoperative 6 weeks. Compared with the model group, the therapeutic group presented significant improvements in ejection fraction, fractional shortening, LV end‐systolic dimension and volume of cardiac output. The number of capillary vessels increased distinctly, while the infarct area decreased correspondingly.ConclusionsIn conclusion, these findings validate the proposed rabbit model and prove that the interaction of the degenerated coronary vasculature and increased ventricle wall stress relevant to cardiac fibrosis in vicinity of myocardial infarction (MI) facilitates the occurrence and development of ischemic HF. Furthermore, Tongxinluo Capsule has been proved in our study to play an essential role in protecting myocardium, improving blood supply of myocardium and relieving myocardial injury. To summarize, the post‐MI rabbit model can serve as a reference to test various drugs for treatment of ischemic HF, and contributes to the clinical application of Tongxinluo Capsule in the future.Support or Funding InformationThis research is supported in part by the National Natural Science Foundation of China Grant 11372010, 11672006 (Y Huo); Shenzhen Science and Technology Innovation Institution (China) Grant JCYJ20160427170536358 (Y Huo); and Hebei University (China) Grant 2015A1002 (Y Huo).This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Enhanced NLRP3 Inflammasome Activation in the Arterial Endothelium with Acid Sphingomyelinase Transgene in Mice
Authors: Yuan Xinxu , Bhat Owais M. , Lohner Hannah , Li Pin‐Lan 
Published: June 2021

Endothelial NLPR3 inflammasome activation during hypercholesterolemia triggers arterial inflammation and neointima formation leading to atherosclerosis. However, the mechanisms activating and regulating NLRP3 inflammasomes remain poorly understood. The present study investigated whether endothelial acid sphingomyelinase (ASM) and its product, ceramide are required for endothelial NLRP3 inflammasome activation and atherosclerotic lesions during hypercholesterolemia. We fed Smpd1trg/ECcre mice, a mouse strain with endothelial (EC)‐specific ASM transgene (Smpd1 is the code for mouse ASM gene) and their control littermates (Smpd1trg/WT and WT/WT mice) with the Western diet (WD) and then performed partial left carotid ligation (PLCA). With such animal model, we found that the neointima formation in the carotid artery with ligation was more remarkably increased by 2.6 folds in Smpd1trg/ECcre mice than their control littermates. Using confocal microscopy, enhanced colocalization of NLRP3 with ASC or with caspase‐1 was found in the endothelium of the carotid arteries in WD‐treated Smpd1trg/ECcre mice, which was much less in their control littermates. IL‐1β levels in the carotid intima also more significantly increased by 2.2 folds in Smpd1trg/ECcre mice, which was accompanied by overexpression of ASM and elevated ceramide level. In addition, flotilin‐1 as a membrane raft (MR) marker was found to be aggregated with ASM, ceramide, gp91phox and p47phox more in the intima of Smpd1trg/ECcre mice than their control littermates. Carotid intimal O2.− levels as measured by in situ dihydroethidium (DHE) staining was much higher in WD‐treated Smpd1trg/ECcre mice than their controls. These results suggest that ASM or ceramide‐mediated MR redox signaling platform formation and NADPH oxidase activation are essential for endothelial NLRP3 inflammasome activation and consequent atherogenic changes in the arterial wall during hypercholesterolemia.Support or Funding InformationNIH grants HL057244, HL075316 and HL122937).This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.