Search bioRxiv⌕ Search

Biology subjects

Tang, W. W.

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

3 recordsLinked to original sources

Gut microbiome shifts in chronic systolic heart failure are associated with disease severity and clinical improvement

Chronic systolic heart failure (HF) is a prevalent and morbid disease with marked variability in its progression and response to therapies. The gut microbiome may play a role in pathophysiology and progression of chronic HF, but clinical studies investigating relationships between the two are lacking. We analyzed the gut microbiome in a cohort of adults with chronic systolic HF caused by non-ischemic cardiomyopathy (n=59) using multi-omics profiling and, in some cases, longitudinal sampling. We identified microbiome differences compared to healthy subjects (n=50) and associated these differences with host metabolites, inflammatory markers and physiology. We found depletion of the anti-inflammatory probiotic Bifidobacterium and the associated short chain fatty acid producing and formaldehyde detoxifying pathways in the chronic HF cohort. We also discovered HF-specific microbiome-host immunome interactions. In addition to identifying several taxa and microbial pathways broadly associated with HF disease severity, we found significant links between Bifidobacterium and clinical HF improvement over time. Gut microbiome-host multi-omic data integration revealed a close association between Bifidobacterium and circulating metabolites previously implicated in cardiovascular physiology (e.g., malonic acid), thus pointing to potential mechanisms through which Bifidobacterium may affect chronic HF physiology. Our results suggest that Bifidobacterium may serve as a biomarker for chronic HF trajectory as well as suggest potential novel therapeutic interventions strategies.

microbiology↗

FAM114A1 Influences Cardiac Fibrosis by Regulating Angiotensin II Signaling in Cardiac Fibroblasts

Cardiac fibrosis, a primary contributor to heart failure (HF) and sudden death, is considered as an important target for HF therapy. However, the signaling pathways that govern cardiac fibroblast (CF) function during cardiac fibrosis have not been fully elucidated. Here, we found that a functionally unannotated human myocardial infarction (MI) associated gene, family with sequence similarity 114 member A1 (FAM114A1), is induced in failing human and mouse hearts compared to non-failing hearts. Homozygous knockout of Fam114a1 (Fam114a1-/-) in the mouse genome reduces cardiac hypertrophy and fibrosis while significantly restores cardiac function in angiotensin (Ang) II- and MI-induced HF mouse models. Fam114a1 deletion antagonizes Ang II induced inflammation and oxidative stress. Using isolated mouse primary CFs in wild type and Fam114a1-/- mice, we found that FAM114A1 is a critical autonomous factor for CF proliferation, activation, and migration. We discovered that FAM114A1 interacts with angiotensin receptor associated protein (AGTRAP) and regulates the expression of angiotensin type 1 receptor (AT1R) and downstream Ang II signaling transduction, and subsequently influences pro-fibrotic response. Using RNA-Seq in mouse primary CFs, we identified differentially expressed genes including extracellular matrix proteins such as Adamts15. RNAi-mediated inactivation of Adamts15 attenuates CF activation and collagen deposition. Our results indicate that FAM114A1 regulates Ang II signaling and downstream pro-fibrotic and pro-inflammatory gene expression, thereby activating cardiac fibroblasts and augmenting pathological cardiac remodeling. These findings provide novel insights into regulation of cardiac fibrosis and identify FAM114A1 as a new therapeutic target for treatment of cardiac disease. SignificanceCardiac fibrosis is a hallmark of heart failure and angiotensin II signaling promotes pro-fibrotic response in the heart. This study is a pioneering investigation of the role of a functionally unknown protein FAM114A1. We show that FAM114A1 expression is induced in human and mouse failing hearts. Genetic ablation of FAM114A1 can effectively reduce cardiac fibrosis and pathological remodeling. Isolated cardiac fibroblasts from Fam114a1 knockout mice show reduced response to Ang II stimulation and compromised myofibroblast activation. Mechanistically, FAM114A1 binds to AGTRAP and influences AT1R protein expression, thereby enhancing angiotensin II signaling and pro-fibrotic response. Thus, FAM114A1 is a novel factor that modulates cardiac fibrosis and pharmacological inhibition of FAM114A1 may be a therapeutic strategy for the treatment of heart disease.

pathology↗

Transposable elements resistant to epigenetic resetting in the human germline are epigenetic hotspots for development and disease

Despite the extensive erasure of DNA methylation in the early human germline, nearly eight percent of CpGs are resistant to the epigenetic resetting in the acutely hypomethylated primordial germ cells (week 7-9 hPGCs). Whether this occurs stochastically or represents relatively conserved layer of epigenetic information is unclear. Here we show that several predominantly hominoid-specific families of transposable elements (TEs) consistently resist DNA demethylation (henceforth called hPGC-methylated TEs or escapees) during the epigenetic resetting of hPGCs. Some of them undergo subsequent dynamic epigenetic changes during embryonic development. Our analysis of the fetal cerebral cortex also revealed multiple classes of young hPGC-methylated TEs within putative and established enhancers. Remarkably, specific hPGC-methylated TE subfamilies were associated with a multitude of adaptive human traits, including hair color and intelligence, and diseases including schizophrenia and Alzheimers disease. We postulate that hPGC-methylated TEs represent potentially heritable information within the germline with a role in human development and evolution.

developmental biology↗