Ethanol extracts of unroasted Coffea canephora robusta beans suppress adipogenesis in preadipocytes and fat accumulation in rats fed a high-fat diet

Anti-adipogenic and anti-obesity effects of a green coffee been extract (GCE) from unroasted Coffea canephora Robusta beans were investigated in vitro and in vivo. Insulin-induced adipogenesis in 3T3-L1 preadipocytes was inhibited by 25.6 and 87.9% following treatment with 100 and 500 μg/mL GCE, respectively. Expression of adipogenesis-specific genes was down-regulated. Body weight gains of C57BL/6 mice fed a high-fat diet (HFD) were suppressed in a concentration-dependent manner using GCE (0.3 or 1% in the diet), exhibiting a marked lower gain in 1% GCE-fed mice than in normal diet-fed animals. Decreases in body fat weights and the size of adipocytes were confirmed. GCE supplementation reduced concentrations of blood lipids and leptin, and attenuated hepatic steatosis. GCE inhibits adipogenesis by modulating cell signaling and improves dietary obesity by reducing lipid accumulation and the size of adipocytes.