Biology subjects

Tang, W. H. W.

Publications and source records attributed to Tang, W. H. W..

7 recordsLinked to original sources

bioRxiv2024

Dysregulation of Nitrosylation Dynamics Promotes Nitrosative Stress and Contributes to Cardiometabolic Heart Failure with Preserved Ejection Fraction

BackgroundRecent reports suggest increased myocardial iNOS expression leads to excessive protein s-nitrosylation, contributing to the pathophysiology of HFpEF. However, the relationship between NO bioavailability, dynamic regulation of protein s-nitrosylation by trans- and de-nitrosylases, and HFpEF pathophysiology has not been elucidated. Here, we provide novel insights into the delicate interplay between NO bioavailability and protein s-nitrosylation in HFpEF. MethodsPlasma nitrite, nitrosothiols (RsNO), and 3-nitrotyrosine (3-NT) were measured in HFpEF patients and in controls. Studies in WKY or ZSF1 obese rats were performed to evaluate HFpEF severity, NO signaling, and total nitroso-species (Rx(s)NO) levels. snRNA sequencing was performed to identify key genes involved in NO signaling and s-nitrosylation regulation. ResultsIn HFpEF patients, circulating RsNO and 3-NT were significantly elevated while nitrite, a biomarker for NO bioavailability, remained unchanged. In ZSF1 obese rats, NO bioavailability was significantly reduced while Rx(s)NO levels exhibited an age-dependent increase as HFpEF progressed. snRNA seq highlighted significant upregulation of a trans-nitrosylase, hemoglobin-beta subunit (HBb), which was corroborated in human HFpEF hearts1. Subsequent experiments confirmed HBb upregulation and revealed significant reductions in enzyme activity of two major de-nitrosylases, Trx2 and GSNOR in ZSF1 obese hearts. Further, elevated RxNO levels, increased HBb expression, and reduced activity of Trx2 and GSNOR were identified in the kidney and liver of the ZSF1 obese rats. ConclusionsOur data reveal circulating markers of nitrosative stress (RsNO and 3-NT) are significantly elevated in HFpEF patients. Data from the ZSF1 obese rat model mirror the results from HFpEF patients and reveal that pathological accumulation of RxNO/nitrosative stress in HFpEF may be in part, due to the upregulation of the trans-nitrosylase, HBb, and impaired activity of the de-nitrosylases, Trx2 and GSNOR. Our data suggest that dysregulated protein nitrosylation dynamics in the heart, liver, and kidney contribute to the pathogenesis of cardiometabolic HFpEF. Translational PerspectiveOur findings describe for the first time that circulating RsNO and 3-NT are significantly upregulated in HFpEF patients suggesting systemic nitrosative stress in HFpEF, and demonstrate a profound disconnect between insufficient physiological NO signaling and pathological nitrosative stress in HFpEF, which is in stark contrast to HFrEF in which both NO bioavailability and protein s-nitrosylation are attenuated. Further, this study provides novel mechanistic insights into a critical molecular feature of HFpEF in humans and animal models: nitrosative stress arises predominantly from imbalance of trans-nitrosylases and de-nitrosylases, thereby leading to impaired NO bioavailability concomitant with increased protein s-nitrosylation. Importantly, these perturbations extend beyond the heart to the kidney and liver, suggesting HFpEF is characterized by a systemic derangement in trans- and de-nitrosylase activity and providing a unifying molecular lesion for the systemic presentation of HFpEF pathophysiology. These findings have direct clinical implications for the modulation of NO levels in the HFpEF patient, and indicate that restoring the balance between trans- and denitrosylases may be novel therapeutic targets to ameliorate disease symptoms in HFpEF patients.

physiology↗

bioRxiv2024

Reduced Hydrogen Sulfide Bioavailability Contributes to Cardiometabolic Heart Failure with Preserved Ejection Fraction

BackgroundHeart failure with preserved ejection fraction (HFpEF) is a significant public health concern with limited treatment options. Dysregulated nitric oxide-mediated signaling has been implicated in HFpEF pathophysiology, however, little is known about the role of endogenous hydrogen sulfide (H2S) in HFpEF. ObjectivesThis study evaluated H2S bioavailability in patients and two animal models of cardiometabolic HFpEF and assessed the impact of H2S on HFpEF severity through alterations in endogenous H2S production and pharmacological supplementation. We also evaluated the effects of the H2S donor, diallyl trisulfide (DATS) in combination with the GLP-1/glucagon receptor agonist, survodutide, in HFpEF. MethodsHFpEF patients and two rodent models of HFpEF ("two-hit" L-NAME + HFD mouse and ZSF1 obese rat) were evaluated for H2S bioavailability. Two cohorts of two-hit mice were investigated for changes in HFpEF pathophysiology: (1) endothelial cell cystathionine-{gamma}-lyase (EC-CSE) knockout; (2) H2S donor, JK-1, supplementation. DATS and survodutide combination therapy was tested in ZSF1 obese rats. ResultsH2S levels were significantly reduced (i.e., 81%) in human HFpEF patients and in both preclinical HFpEF models. This depletion was associated with reduced CSE expression and activity, and increased SQR expression. Genetic knockout of H2S -generating enzyme, CSE, worsened HFpEF characteristics, including elevated E/e ratio and LVEDP, impaired aortic vasorelaxation and increased mortality. Pharmacologic H2S supplementation restored H2S bioavailability, improved diastolic function and attenuated cardiac fibrosis corroborating an improved HFpEF phenotype. DATS synergized with survodutide to attenuate obesity, improve diastolic function, exercise capacity, and reduce oxidative stress and cardiac fibrosis. ConclusionsH2S deficiency is evident in HFpEF patients and conserved across multiple preclinical HFpEF models. Increasing H2S bioavailability improved cardiovascular function, while knockout of endogenous H2S production exacerbated HFpEF pathology and mortality. These results suggest H2S dysregulation contributes to HFpEF and increasing H2S bioavailability may represent a novel therapeutic strategy for HFpEF. Furthermore, our data demonstrate that combining H2S supplementation with GLP-1/glucagon receptor agonist may provide synergistic benefits in improving HFpEF outcomes. HighlightsO_LIH2S deficiency is evident in both human HFpEF patients and two clinically relevant models. C_LIO_LIReduced H2S production by CSE and increased metabolism by SQR impair H2S bioavailability in HFpEF. C_LIO_LIPharmacological H2S supplementation improves diastolic function and reduces cardiac fibrosis in HFpEF models. C_LIO_LITargeting H2S dysregulation presents a novel therapeutic strategy for managing HFpEF. C_LIO_LIH2S synergizes with GLP-1/glucagon agonist and ameliorates HFpEF C_LI

pharmacology and toxicology↗

bioRxiv2023

FAM210A Regulates Mitochondrial Translation and Maintains Cardiac Mitochondrial Homeostasis

AimsMitochondria play a vital role in cellular metabolism and energetics and support normal cardiac function. Disrupted mitochondrial function and homeostasis cause a variety of heart diseases. Fam210a (family with sequence similarity 210 member A), a novel mitochondrial gene, is identified as a hub gene in mouse cardiac remodeling by multi-omics studies. Human FAM210A mutations are associated with sarcopenia. However, the physiological role and molecular function of FAM210A remain elusive in the heart. We aim to determine the biological role and molecular mechanism of FAM210A in regulating mitochondrial function and cardiac health in vivo. Methods and ResultsTamoxifen-induced MHCMCM-driven conditional knockout of Fam210a in the mouse cardiomyocytes induced progressive dilated cardiomyopathy and heart failure, ultimately causing mortality. Fam210a deficient cardiomyocytes exhibit severe mitochondrial morphological disruption and functional decline accompanied by myofilament disarray at the late stage of cardiomyopathy. Furthermore, we observed increased mitochondrial reactive oxygen species production, disturbed mitochondrial membrane potential, and reduced respiratory activity in cardiomyocytes at the early stage before contractile dysfunction and heart failure. Multi-omics analyses indicate that FAM210A deficiency persistently activates integrated stress response (ISR), resulting in transcriptomic, translatomic, proteomic, and metabolomic reprogramming, ultimately leading to pathogenic progression of heart failure. Mechanistically, mitochondrial polysome profiling analysis shows that FAM210A loss of function compromises mitochondrial mRNA translation and leads to reduced mitochondrial encoded proteins, followed by disrupted proteostasis. We observed decreased FAM210A protein expression in human ischemic heart failure and mouse myocardial infarction tissue samples. To further corroborate FAM210A function in the heart, AAV9-mediated overexpression of FAM210A promotes mitochondrial-encoded protein expression, improves cardiac mitochondrial function, and partially rescues murine hearts from cardiac remodeling and damage in ischemia-induced heart failure. ConclusionThese results suggest that FAM210A is a mitochondrial translation regulator to maintain mitochondrial homeostasis and normal cardiomyocyte contractile function. This study also offers a new therapeutic target for treating ischemic heart disease. Translational PerspectiveMitochondrial homeostasis is critical for maintaining healthy cardiac function. Disruption of mitochondrial function causes severe cardiomyopathy and heart failure. In the present study, we show that FAM210A is a mitochondrial translation regulator required for maintaining cardiac mitochondrial homeostasis in vivo. Cardiomyocyte-specific FAM210A deficiency leads to mitochondrial dysfunction and spontaneous cardiomyopathy. Moreover, our results indicate that FAM210A is downregulated in human and mouse ischemic heart failure samples and overexpression of FAM210A protects hearts from myocardial infarction induced heart failure, suggesting that FAM210A mediated mitochondrial translation regulatory pathway can be a potential therapeutic target for ischemic heart disease.

pathology↗

bioRxiv2020

The IgG3 Subclass of β1-adrenergic receptor autoantibody is an endogenous biaser of β1AR signaling

Autoantibodies recognizing human {beta}1ARs generated due to dysregulation in autoimmune response are generally associated with deleterious cardiac outcomes. However, cellular studies show that isolates of {beta}1AR autoantibody from patients differentially modulate {beta}1AR function. {beta}1AR autoantibodies belong to the IgG class of immunoglobulins, however it is not known whether the IgG sub-classes mediate variability in {beta}1AR responses. To determine whether the IgG3 subclass of {beta}1AR autoantibodies uniquely modulate {beta}1AR function, HEK293 cells stably expressing human {beta}1ARs were utilized. Treatment of cells with IgG3(-) serum resulted in significant increase of cAMP compared to IgG3(+) serum. Pre-treatment of cells with IgG3(+) serum impaired dobutamine-mediated Adenylate Cyclase (AC) activity and cAMP generation whereas, it surprisingly increased AC activity and cAMP generation with {beta}-blocker metoprolol. Consistently, purified IgG3(+) {beta}1AR autoantibodies impaired dobutamine-mediated cAMP while elevating metoprolol-mediated AC activity and cAMP. Despite IgG3(+) autoantibodies reducing cAMP response to dobutamine, they mediate significant ERK activation upon dobutamine. IgG3(+) {beta}1AR autoantibodies did not alter {beta}2AR function, reflecting their specificity. The study shows that IgG3(+) {beta}1AR autoantibody impairs agonist-mediated G-protein coupling while preferentially mediating G-protein-independent ERK activation. Furthermore, it uniquely biases {beta}-blocker towards G-protein coupling. This unique biasing capabilities of IgG3(+) {beta}1AR autoantibodies may underlie the beneficial outcomes in patients.

pharmacology and toxicology↗

bioRxiv2020

MicroRNA-574 Regulates FAM210A Expression and Influences Pathological Cardiac Remodeling

Aberrant synthesis of mitochondrial proteins impairs cardiac function and causes heart disease. However, the mechanism of regulation of mitochondria encoded protein expression during cardiac disease remains underexplored. Here, we have shown that multiple pathogenic cardiac stressors induce the expression of miR-574 guide and passenger strands (miR-574-5p/3p) in both humans and mice. miR-574 knockout mice exhibit severe cardiac disorder under heart disease-triggering stresses. miR-574-5p/3p mimics that are delivered systematically using nanoparticles reduce cardiac pathogenesis under disease insults. Transcriptome analysis of miR-574-null hearts uncovers FAM210A as a common target mRNA for both strands of miR-574. The interactome capture and translational state analyses suggest that FAM210A interacts with mitochondrial translation factors and regulates the protein expression of mitochondrial encoded electron transport chain genes. Using a human cardiomyocyte cell culture system, we discover that miR-574 regulates FAM210A expression and modulates mitochondrial encoded protein expression, which influences cardiac remodeling in heart failure.

pathology↗

bioRxiv2019

EPRS Regulates Proline-rich Pro-fibrotic Protein Synthesis during Cardiac Fibrosis

RationaleIncreased protein synthesis of pro-fibrotic genes is a common feature of cardiac fibrosis, a major manifestation of heart failure. Despite this important observation, critical factors and molecular mechanisms for translational control of pro-fibrotic genes during cardiac fibrosis remain unclear.\n\nObjectiveThis study aimed to test the hypothesis that cardiac stress-induced expression of a bifunctional aminoacyl-tRNA synthetase (ARS), glutamyl-prolyl-tRNA synthetase (EPRS), is preferentially required for the translation of proline codon-rich (PRR) pro-fibrotic mRNAs in cardiac fibroblasts during cardiac fibrosis.\n\nMethods and ResultsBy analyses of multiple available unbiased large-scale screening datasets of human and mouse heart failure, we have discovered that EPRS acts as an integrated node among all the ARSs in various cardiac pathogenic processes. We confirmed that EPRS was induced at both mRNA and protein level ([~]1.5-2.5 fold increase) in failing hearts compared with non-failing hearts using our cohort of human and mouse heart samples. Genetic knockout of one allele of Eprs globally (Eprs+/-) using CRISPR-Cas9 technology or in a myofibroblast-specific manner (Eprsflox/+; PostnMCM/+) strongly reduces cardiac fibrosis ([~]50% reduction) in isoproterenol- and transverse aortic constriction-induced heart failure mouse models. Inhibition of EPRS by a prolyl-tRNA synthetase (PRS)-specific inhibitor, halofuginone (Halo), significantly decreased the translation efficiency of proline-rich collagens in cardiac fibroblasts. Furthermore, using transcriptome-wide RNA-Seq and polysome profiling-Seq in Halo-treated fibroblasts, we identified multiple novel Pro-rich genes in addition to collagens, such as Ltbp2 and Sulf1, which are translationally regulated by EPRS. As a major EPRS downstream effector, SULF1 is highly enriched in human and mouse myofibroblast. siRNA-mediated knockdown of SULF1 attenuates cardiac myofibroblast activation and collagen deposition.\n\nConclusionsOur results indicate that EPRS preferentially controls the translational activation of proline codon-rich pro-fibrotic genes in cardiac fibroblasts and augments pathological cardiac remodeling.\n\nNovelty and SignificanceO_ST_ABSWhat is known?C_ST_ABSO_LITGF-{beta} and IL-11 increase synthesis of pro-fibrotic proteins during cardiac fibrosis.\nC_LIO_LIMany pro-fibrotic genes contain Pro genetic codon rich motifs such as collagens.\nC_LIO_LIEPRS is an essential house-keeping enzyme required for ligating Pro to tRNAPro for the synthesis of Pro-containing proteins.\nC_LI\n\nWhat New Information Does This Article Contribute?O_LIThis study is a pioneering investigation of translational control mechanisms of pro-fibrotic gene expression in cardiac fibrosis.\nC_LIO_LIEPRS mRNA and protein expression are induced in failing human hearts and mouse hearts undergoing pathological cardiac remodeling.\nC_LIO_LIThe first demonstration of the in vivo function of EPRS in cardiac remodeling. Heterozygous Eprs global knockout and myofibroblast-specific tamoxifen-inducible Eprs conditional knockout mice show reduced pathological cardiac fibrosis under stress, suggesting that the reduction of EPRS is cardioprotective.\nC_LIO_LIIdentification of novel preferential translational target genes of EPRS. We found that EPRS regulates translation of Pro-rich (PRR) transcripts, which comprise most of the ECM and secretory signaling molecules. Among those targets, we identified multiple novel PRR genes such as LTBP2 and SULF1.\nC_LIO_LISULF1 is validated as a myofibroblast marker protein in human and mouse heart failure and a potential anti-fibrosis target gene.\nC_LI\n\nIn cardiac fibroblasts, the synthesis of pro-fibrotic proteins is upregulated by cardiac stressors to activate extracellular matrix deposition and impair cardiac function. In this study, we have discovered an EPRS-PRR gene axis that influences translational homeostasis of pro-fibrotic proteins and promotes pathological cardiac remodeling and fibrosis. EPRS is identified as a common node downstream of multiple cardiac stressors and a novel regulatory factor that facilitates pro-fibrotic mRNA translation in cardiac fibrosis. Global and myofibroblast-specific genetic ablation of EPRS can effectively reduce cardiac fibrosis. This study reveals a novel translational control mechanism that modulates cardiac fibrosis and heart function. Mild inhibition of PRR mRNA translation could be a general therapeutic strategy for the treatment of heart disease. These findings provide novel insights into the translational control mechanisms of cardiac fibrosis and will promote the development of novel therapeutics by inhibiting pro-fibrotic translation factors or their downstream effectors.

pathology↗

bioRxiv2019

The circulating lipidome is largely defined by sex descriptors in the GOLDN, GeneBank and the ADNI studies

Biological sex is one of the major anthropometric factors which influences physiology, metabolism and health status. We have investigated the effect of sexual dimorphism on the blood lipidome profile in three large population level studies - the Alzheimers disease neuroimaging initiative - ADNI (n =806), the GeneBank Functional Cardio-Metabolomics cohort (n= 1015) and the Genetics of Lipid lowering Drugs and Diet Network - GOLDN (n=422). In total, 355 unique lipids from 15 lipid classes were detected across all three studies using LC-MS. Sixty percent of these lipids differed between men and women in all three cohorts, and up to 87% of all lipids demonstrated sex differences in at least one cohort. ChemRICH enrichment statistics on lipid classes showed that phosphatidylcholines, phosphatidylethanolamines, phosphatidylinositols, ceramides, sphingomyelins and cholesterol esters were found at higher levels in female subjects while triacylglycerols and lysophosphatidylcholines were found at higher levels in male participants across the three cohorts. This strong sex effect on the blood lipidome suggests that specific regulatory mechanisms may exist that regulate lipid metabolism in a different manner between men and women. Cohort studies involving blood lipidomics should consider separate analyses for male and female participants instead of combined analyses treating sex as a confounding factor.

biochemistry↗