Lipolysis by downregulating miR-92a activates the Wnt/β-catenin signaling pathway in hypoxic rats

Biomed Rep. 2020 Oct;13(4):33. doi: 10.3892/br.2020.1340. Epub 2020 Aug 4.

Abstract

The aim of the present study was to investigate the role of miR-92a in lipid metabolism in hypoxic rats. Microarray analysis and reverse transcription-quantitative (RT-q)PCR were used to detect changes in the mRNA expression levels of miR-92a in the epididymal fat of hypoxic and normoxic rats. The downstream target mRNA of miR-92a was predicted using bioinformatics analysis and verified using a dual luciferase reporter assay. Changes in the expression of frizzled (Fzd)10 and c-Myc in the epididymal fat were detected using RT-qPCR and western blotting. Microarray analysis and RT-qPCR results showed that the expression of miR-92a was significantly lower in the fat tissues of the hypoxic rats compared with the normoxic rats. The results of the dual luciferase reporter assay showed that the target gene of miR-92a was Fzd10, which is an acceptor in the Wnt pathway. Fzd10 expression was upregulated in the hypoxic rats. The mRNA expression levels of c-Myc, which is located downstream of the Wnt pathway, was increased significantly. The increase in the mRNA and protein expression levels of Fzd10 and c-Myc may be associated with miR-92a downregulation. Downregulation of miR-92a in-turn may result in lipolysis through the regulation of the Wnt/β-catenin signaling pathway, and thus weight loss in the rats.

Keywords: Wnt/β-catenin signaling pathway; frizzled 10; hypoxic training; lipolysis; microRNA-92a.