Weighted Gene Co-Expression Network Analysis Identifies ANGPTL4 as a Key Regulator in Diabetic Cardiomyopathy via FAK/SIRT3/ROS Pathway in Cardiomyocyte

Abstract

BackgroundDiabetic cardiomyopathy (DbCM) is characterized by initial impairment of left ventricular relaxation followed by contractile dysfunction. Despite intensive research, the exact mechanism remains so far unsolved.MethodsWe constructed weighted gene co-expression network analysis (WGCNA) to screen gene modules that were closely related with DbCM based on the GSE5606 dataset, which contained expression data of the cardiac left ventricle in a rodent model of streptozotocin (STZ)-induced DbCM. Then, the most related hub gene, angiopoietin-like 4 (ANGPTL4), was selected for functional ex vivo and in vitro assays. In our experiments, STZ-induced diabetic mice (C57BL/6J) and human cardiomyocytes (AC16) were used to study the functional roles and potential mechanisms of ANGPTL4 in DbCM.ResultsWGCNA analysis revealed the yellow and green modules were most correlated with DbCM, and identified ANGPTL4 as one of the most significantly upregulated hub genes (ANGPTL4, ACOT1, DECR1, HMGCS2, and PDK4). Consistent with the bioinformatic analysis, the amount of ANGPTL4 was significantly upregulated in diabetic mouse heart. DbCM group, compared with the control group, had increased phosphorylation of focal adhesion kinase (FAK), reduced SIRT3 expression, increased SOD2 acetylation, upregulated NADPH oxidase activation, elevated reactive oxygen species (ROS) produciton, and enhanced apoptosis in the diabetic mouse heart. Moreover, ANGPTL4 induced apoptosis via FAK/SIRT3/ROS pathway in human cardiomyocytes (AC16) under high glucose condition in vitro.These effects were abrogated by treatment of two independent siRNA for ANGPTL4, whereas exogenous recombinant ANGPLT4 protein treatment exacerbated those effects in AC16.ConclusionWe found ANGPTL4, ACOT1, DECR1, HMGCS2, and PDK4 were significantly increased in diabetic heart. ANGPTL4 could promote cardiac apoptosis via a FAK/SIRT3/ROS dependent signaling pathway in DbCM.

ANGPTL4 Regulates Psoriasis via Modulating Hyperproliferation and Inflammation of Keratinocytes

“…ANGPTL4 regulates inflammation, proliferation, lipid metabolism, vessel permeability, and tumor progression. Our previous study has found ANGPTL4 as a key regulator in diabetic cardiomyopathy via FAK/SIRT3/ROS pathway in cardiomyocyte ( Dai et al, 2021 ). ANGPTL4 also stimulates STAT3-mediated iNOS expression and enhances angiogenesis to accelerate wound healing in diabetic mice ( Chong et al, 2014 ).…”

“…Unassigned background genes that belonged to none of the modules were denoted with the grey section. The module eigengenes (MEs) and module significance (MS) were defined as previously described ( Dai et al, 2021 ). We applied the MEs and MS to identify the significant module related to psoriasis.…”

Identification of Hub Genes Associated with Diabetic Cardiomyopathy Using Integrated Bioinformatics Analysis

“…A recent study by Reichelt et al also predicted that high fructose-induced myocardial TG and glycogen accumulation is attributable to increased Pdk4 38 . Furthermore, Pdk4 was identi ed as a DCM susceptibility gene in a previous WGCNA on diabetic heart 39 .…”

Cardiac Acetylation in Metabolic Diseases

“…Moreover, in a model of sucrose-fed rats, cardiac dysfunction is associated with a decreased SIRT3 protein expression (despite an increase at RNA level) and an increased GCN5L1 (protein and RNA) and mitochondrial protein acetylation [ 11 , 17 ]. Decreased SIRT3 levels are also associated with an increased acetylation of SOD2, and an increased oxidative stress and apoptosis in heart of diabetic mice [ 79 ]. Interestingly, exposure of cardiomyoblasts H9c2 to high glucose concentration decreased SIRT3 [ 78 ] and increased GCN5L1, oxidative stress and autophagy mediated by cytoplasmic Forkhead box O1 (FOXO1) acetylation [ 11 , 76 ].…”