Persimmon tannin represses 3T3-L1 preadipocyte differentiation via up-regulating expression of miR-27 and down-regulating expression of peroxisome proliferator-activated receptor-γ in the early phase of adipogenesis

Currently, obesity has become a worldwide health problem. Adipocyte differentiation is closely associated with the onset of obesity. Our previous studies suggested that persimmon tannin might be a potent anti-adipogenic dietary bioactive compound. However, the mechanism of persimmon tannin on adipocyte differentiation is still unknown. The purpose of this study was to investigate the effect of persimmon tannin on adipogenic differentiation in 3T3-L1 preadipocytes and the underlying mechanisms. Adipogenic differentiation was induced by cocktail in the presence or absence of persimmon tannin. Intracellular lipid accumulation was determined by Oil red O staining and enzymatic colorimetric methods. Gene expression and protein levels were measured by real time RT-PCR and Western blot. Persimmon tannin inhibited intracellular lipid accumulation markedly, and the inhibitory effect was largely limited to the early stage of adipocyte differentiation. Persimmon tannin suppressed the expression of C/EBPα and peroxisome proliferator-activated receptor-γ (PPARγ), significantly. Furthermore, genes related to lipogenesis, such as sterol regulatory element-binding protein 1, were down-regulated by persimmon tannin. In addition, adipocyte fatty acid binding protein (aP2), which is a target gene of PPARγ, was suppressed by persimmon tannin notably. Correspondingly, the expression of miR-27a and miR-27b were up-regulated by persimmon tannin from Day 2 to Day 8 significantly. Persimmon tannin inhibited adipocyte differentiation through regulation of PPARγ, C/EBPα and miR-27 in early stage of adipogenesis.