MiR-378a-3p enhances adipogenesis by targeting mitogen-activated protein kinase 1

• MiR-378a-3p is up-regulated in adipose tissues of HFD-fed mice, as well as during the differentiation of 3T3-L1 preadipocytes.
• MiR-378a-3p enhances adipogenesis in 3T3-L1 cells.
• MiR-378a-3p induces adipogenesis by directly targeting MAPK1 which markedly decreases at the later stage of adipogenesis.

Previous studies showed that miR-378a plays important roles in adipogenesis and obesity; however, the precise mechanisms of action remain unknown. Here, we found that miR-378a-3p expression is up-regulated in adipose tissues of high fat diet-induced obese mice, as well as during the differentiation of 3T3-L1 preadipocytes. Mir-378a-3p induced adipogenesis by targeting mitogen-activated protein kinase 1 (MAPK1). Overexpression of miR-378a-3p or silencing MAPK1 reduced MAPK1 expression and enhanced adipogenesis, whereas blockage of endogenous miR-378a-3p had the opposite effect, suggesting that miR-378a-3p promotes the adipogenesis of 3T3-L1 cells by targeting MAPK1.