LncRNA MEG3 aggravates palmitate-induced insulin resistance by regulating miR-185-5p/Egr2 axis in hepatic cells.

Abstract

Long non-coding RNA (LncRNA) has been reported to play an important role in type 2 diabetes (T2D). We investigated the role of LncRNA maternally expressed gene 3 (MEG3) and its potential interaction with miR-185-5p in palmitate-induced hepatocyte insulin resistance. High-fat diet (HFD) mice and insulin resistant hepatocyte were employed. Relative mRNA expressions of MEG3, miR-185-5p, and early growth response proteins-2 (Egr2) were measured by qRT-PCR. Western blot was performed to evaluate Egr2 protein expression levels. Glycogen contents and plasma insulin levels were tested by the corresponding assay. MEG3 and Egr2 were upregulated, but miR-185-5p was downregulated in palmitate-treated insulin resistance hepatocytes and HFD mice. MEG3 knockdown alleviated the influence of palmitate on insulin resistance in vitro and in vivo. miR-185-5p expression was upregulated upon MEG3 knockdown. Expression of Egr2 was positively correlated with MEG3 knockdown or overexpression, which could be negatively managed by abnormal expression of miR-185-5p. Our data demonstrated that LncRNA MEG3 aggravated palmitate-induced insulin resistance by regulating miR-185-5p/Egr2 axis, providing new insights into T2D therapeutic strategies.