Results:

VSG led to a reduction in body weight and fat mass in both Clock Δ19 mutant and constant-light mouse models (P< 0.05), resulting in an overall metabolic improvement independent of circadian disruption. Interestingly, the decrease in body weight occurred without altering diurnal feeding or activity patterns (P> 0.05). Within circadian-disrupted models, VSG also led to improved glucose tolerance and lipid handling (P< 0.05).

Conclusions:

Together these data demonstrate that VSG is an effective treatment for the obesity associated with circadian disruption, and that the potent effects of bariatric surgery are orthogonal to circadian biology. However, as the effects of bariatric surgery are independent of circadian disruption, VSG cannot be considered a cure for circadian disruption. These data have important implications for circadian-disrupted obese patients. Moreover, these results reveal new information about the metabolic pathways governing the effects of bariatric surgery as well as of circadian disruption.