Objective: Development of brown-like/beige adipocytes in white adipose tissue (WAT) helps to reduce obesity. Thus we investigated the effects of resveratrol, a dietary polyphenol capable of preventing obesity and related complications in humans and animal models, on brown-like adipocyte formation in inguinal WAT (iWAT).
Methods: CD1 female mice (5-month old) were fed a high-fat diet with/without 0.1% resveratrol. In addition, primary stromal vascular cells separated from iWAT were subjected to resveratrol treatment. Markers of brown-like (beige) adipogenesis were measured and the involvement of AMP-activated protein kinase (AMPK) α1 was assessed using conditional knockout.
Results: Resveratrol significantly increased mRNA and/or protein expression of brown adipocyte markers, including uncoupling protein 1 (UCP1), PR domain-containing 16, cell death-inducing DFFA-like effector A, elongation of very long-chain fatty acids protein 3, peroxisome proliferator-activated receptor-γ coactivator 1α, cytochrome c and pyruvate dehydrogenase, in differentiated iWAT stromal vascular cells (SVCs), suggesting that resveratrol induced brown-like adipocyte formation in vitro. Concomitantly, resveratrol markedly enhanced AMPKα1 phosphorylation and differentiated SVC oxygen consumption. Such changes were absent in cells lacking AMPKα1, showing that AMPKα1 is a critical mediator of resveratrol action. Resveratrol also induced beige adipogenesis in vivo along with the appearance of multiocular adipocytes, increased UCP1 expression and enhanced fatty acid oxidation.
Conclusions: Resveratrol induces brown-like adipocyte formation in iWAT via AMPKα1 activation and suggest that its beneficial antiobesity effects may be partly due to the browning of WAT and, as a consequence, increased oxygen consumption.