Effect of resveratrol on visceral white adipose tissue inflammation and insulin sensitivity in a mouse model of sleep apnea

BACKGROUND: Sleep fragmentation (SF) increases food intake and the risk of obesity, and recruits macrophages to visceral white adipose tissue (VWAT) promoting tissue inflammation and insulin resistance. Administration of resveratrol (Resv) has been associated with significant improvements in high-fat diet-induced obesity, inflammation and insulin resistance. METHODS: Male mice were subjected to SF or sleep control conditions for 8 weeks, and treated with either Resv or vehicle (Veh). Fasting plasma levels of glucose, insulin and leptin were obtained and VWAT insulin sensitivity tests were performed (phosphorylated AKT/total AKT), along with flow-cytometric assessments for VWAT macrophages (M1 and M2) and T-cell lymphocytes (CD4+, CD8+ and T regulatory cell (Treg)). RESULTS: SF-Veh and SF-Resv mice showed increased food consumption and weight gain. However, although SF-Veh mice exhibited increased fasting insulin and leptin levels, and reduced VWAT p-AKT/AKT responses to insulin, such alterations were abrogated in SF-Resv-treated mice. Increases in M1, reduced M2 counts and increased tumor necrosis factor-alpha release emerged in SF-Veh macrophages compared with all other three groups. Similarly, increased CD8+ and reduced Treg lymphocyte counts were apparent in SF-Veh. CONCLUSIONS: Resveratrol does not reverse the SF-induced increases in food intake and weight gain, but markedly attenuates VWAT inflammation and insulin resistance, thereby providing a potentially useful adjunctive therapy in the context of sleep disorders manifesting metabolic morbidity.