Inhibitory effects of oxyresveratrol and cyanomaclurin on adipogenesis of 3T3-L1 cells

• Oxyresveratrol and cyanomaclurin led to a dose-dependent decrease in triglyceride accumulation in 3T3-L1 cells.
• Oxyresveratrol and cyanomaclurin inhibited differentiation through inducing cell cycle arrest.
• Oxyresveratrol and cyanomaclurin down-regulated the protein expression of major transcriptional factors in adipogenesis.

Many phenolics are known to possess anti-obesity properties through mechanisms that inhibit adipogenesis, stimulate lipolysis or induce apoptosis. This study aimed to examine the anti-adipogenic effects of two phenolics, oxyresveratrol and cyanomaclurin in 3T3-L1 cells. At doses that they did not induce cytotoxicity (based on the lactate dehydrogenase assay), the exposure of oxyresveratrol (0–100 µM) or cyanomaclurin (0–600 µM) in the first three days of differentiation led to a dose-dependent decrease of triacylglycerol accumulation on day 9 post-confluent. Results of cell proliferation and cell cycle study demonstrated that both compounds inhibited differentiation through inducing cell cycle arrest by retaining the preadipocytes in the G1 phase during the first two days post-confluent. Their anti-adipogenic properties were also attributed to the down-regulation of protein expression of major transcriptional factors in adipogenesis, including peroxisome proliferator-activated receptor γ (PPAR γ) and CCAAT/Enhancer-binding proteins α (C/EBP α), and the induction of cell cycle arrest through regulating cyclin D1, cyclin-dependent kinase 4 (CDK4) and cyclin-dependent kinase inhibitor 1B (P27/kip1) expression during the mitotic clonal expansion period.