Prohibitin (PHB) has been reported to play a crucial role in adipocyte differentiation and mitochondrial function. However, the regulative mechanism of PHB during adipogenesis remains unclear. In this study, we determined that the levels of both microRNA (miR)-27a and miR-27b were down-regulated following adipogenic induction of human adipose-derived stem cells, whereas the mRNA level of PHB was up-regulated. Overexpression of miR-27a or miR-27b inhibited PHB expression and adipocyte differentiation. Using PHB 3'-UTR luciferase reporter assay, we observed that miR-27a and miR-27b directly targeted PHB in human adipose-derived stem cells. A compensation of PHB partially restored the adipogenesis inhibited by miR-27. Moreover, we demonstrated the novel finding that ectopic expression of miR-27a or miR-27b impaired mitochondrial biogenesis, structure integrity, and complex I activity accompanied by excessive reactive oxygen species production. Our data suggest that miR-27 is an anti-adipogenic microRNA partly by targeting PHB and impairing mitochondrial function. Pharmacological modulation of miR-27 function may provide a new therapeutic strategy for the treatment of obesity.
Keywords: Adipogenesis; Cell Differentiation; MicroRNA; Mitochondria; Prohibitin; Stem Cells; miR-27.