Hibiscus extract inhibits the lipid droplet accumulation and adipogenic transcription factors expression of 3T3-L1 preadipocytes.

Objectives: This study was designed to investigate the effect of hibiscus (Hibiscus sabdariffa) on adipogenic differentiation of 3T3-L1 cells at the cellular and molecular levels. Design: Various concentrations of hibiscus extract were added to confluent 3T3-L1 preadipocytes at the outset of the differentiation program and further incubated for 36 hours. Cells were maintained in postdifferentiation medium containing insulin with hibiscus extract in complete culture medium. Results: Hibiscus extract inhibited the adipocyte differentiation of 3T3-L1 preadipocytes induced by insulin, dexamethasone, and isobutylmethylxanthine (IBMX) in a dose-dependent manner. Hibiscus blocked the cytoplasmic lipid accumulation when administered at the onset of differentiation and 4 days after induction of differentiation. The inhibitory effect of hibiscus on adipogenic lipid accumulation of preadipocytes was significant (p < 0.01) between control cells and cells treated with hibiscus. Hibiscus extract significantly attenuated the expression of key adipogenic transcription factors, including CCAAT element binding protein (C/EBP)alpha and peroxisome proliferator-activated receptor (PPAR)gamma at protein levels. Conclusion: These results suggest that hibiscus extract blocks adipogenesis, in part, by its suppression on the expression of adipogenic transcription factors, including C/EBPalpha and PPARgamma.