Long non‐coding ribonucleic acid zinc finger E‐box binding homeobox 1 antisense RNA 1 regulates myocardial fibrosis in diabetes through the Hippo–Yes‐associated protein signaling pathway

AIMS/INTRODUCTION: Fibrosis is the principle reason for heart failure in diabetes. Regarding the involvement of long non‐coding ribonucleic acid zinc finger E‐box binding homeobox 1 antisense 1 (ZEB1‐AS1) in diabetic myocardial fibrosis, we explored its specific mechanism. MATERIALS AND METHODS: Human cardiac fibroblasts (HCF) were treated with high glucose (HG) and manipulated with plasmid cloning deoxyribonucleic acid 3.1‐ZEB1‐AS1/microribonucleic acid (miR)‐181c‐5p mimic/short hairpin RNA specific to sirtuin 1 (sh‐SIRT1). ZEB1‐AS1, miR‐181c‐5p expression patterns, cell viability, collagen I and III, α‐smooth muscle actin (α‐SMA), fibronectin levels and cell migration were assessed by reverse transcription quantitative polymerase chain reaction, cell counting kit‐8, western blot and scratch tests. Nuclear/cytosol fractionation assay verified ZEB1‐AS1 subcellular localization. The binding sites between ZEB1‐AS1 and miR‐181c‐5p, and between miR‐181c‐5p and SIRT1 were predicted and verified by Starbase and dual‐luciferase assays. The binding of SIRT1 to Yes‐associated protein (YAP) and YAP acetylation levels were detected by co‐immunoprecipitation. Diabetic mouse models were established. SIRT1, collagen I, collagen III, α‐SMA and fibronectin levels, mouse myocardium morphology and collagen deposition were determined by western blot, and hematoxylin–eosin and Masson trichrome staining. RESULTS: Zinc finger E‐box binding homeobox 1 antisense 1 was repressed in HG‐induced HCFs. ZEB1‐AS1 overexpression inhibited HG‐induced HCF excessive proliferation, migration and fibrosis, and diminished collagen I, collagen III, α‐SMA and fibronectin protein levels in cells. miR‐181c‐5p had targeted binding sites with ZEB1‐AS1 and SIRT1. SIRT1 silencing/miR‐181c‐5p overexpression abrogated ZEB1‐AS1‐inhibited HG‐induced HCF proliferation, migration and fibrosis. ZEB1‐AS1 suppressed HG‐induced HCF fibrosis through SIRT1‐mediated YAP deacetylation. ZEB1‐AS1 and SIRT1 were repressed in diabetic mice, and miR‐181c‐5p was promoted. ZEB1‐AS1 overexpression improved myocardial fibrosis in diabetic mice, and reduced collagen I, collagen III, α‐SMA and fibronectin protein levels in myocardial tissues. CONCLUSION: Long non‐coding ribonucleic acid ZEB1‐AS1 alleviated myocardial fibrosis through the miR‐181c‐5p–SIRT1–YAP axis in diabetic mice.