Resveratrol directly affects in vitro lipolysis and glucose transport in human fat cells

Resveratrol is a naturally occurring polyphenol found in many dietary sources and red wine. Recognized as a cancer chemoprevention agent, an anti-inflammatory factor and an antioxidant molecule, resveratrol has been proposed as a potential anti-obesity compound and to be beneficial in diabetes. Most of the studies demonstrating the anti-adipogenic action of resveratrol were performed as long-term treatments on cultured preadipocytes. The aim of this study was to analyse the acute effects of resveratrol on glucose uptake and lipolysis in human mature adipocytes. Samples of subcutaneous abdominal adipose tissue were obtained from overweight humans and immediately digested by liberase. Fat cells were incubated (from 45 min to 4 h) with resveratrol 1 mu M-1 mM. Then, glycerol release or hexose uptake was determined. Regarding lipolysis, the significant effects of resveratrol were found at 100 mu M, consisting in a facilitation of isoprenaline stimulation and an impairment of insulin antilipolytic action. At 1 and 10 mu M, resveratrol only tended to limit glucose uptake. Resveratrol 100 mu M did not change basal glucose uptake but impaired its activation by insulin or by benzylamine. This inhibition was not found with other antioxidants. Such impairment of glucose uptake activation in fat cells may led to a reduced availability of glycerol phosphate and then to a decreased triacylglycerol assembly. Therefore, resveratrol increased triacylglycerol breakdown triggered by beta-adrenergic activation and impaired lipogenesis. Consequently, our data indicate that resveratrol can be considered as limiting fat accumulation in human fat cells and further support its use for the mitigation of obesity.