Acer okamotoanum inhibits adipocyte differentiation by the regulation of adipogenesis and lipolysis in 3T3‑L1 cells.

Acer okamotoanum is reported to have various antioxidant, anti‑inflammatory and beneficial immune system effects. The anti‑adipocyte differentiation effects and mechanisms of the ethyl acetate (EtOAc) fraction of an A. okamotoanum extraction was investigated in 3T3‑L1 adipocyte cells. Treatment with differentiation inducers increased the level of triglycerides (TGs) in 3T3‑L1 adipocyte cells compared with an untreated control. However, the EtOAc fraction of A. okamotoanum significantly decreased TGs. Treatment with 1, 2.5 and 5 µg/ml showed weak activity, but TG production was inhibited at 10 µg/ml compared with the control. In addition, A. okamotoanum caused a significant downregulation of proteins related to adipogenesis, such as γ‑cytidine‑cytidine‑adenosine‑adenosine‑thymidine/enhancer binding protein‑α, ‑β and peroxisome proliferator‑activated receptor‑γ, compared with the untreated control. Furthermore, A. okamotoanum significantly upregulated lipolysis related protein, hormone‑sensitive lipase and the phosphorylation of adenosine monophosphate‑activated protein kinase (AMPK). Therefore, these results indicate that A. okamotoanum suppressed adipogenesis and increased lipolysis and the activation of AMPK, suggesting a protective role in adipocyte differentiation.