Populus balsamifera L. (Salicaceae) mitigates the development of obesity and improves insulin sensitivity in a diet-induced obese mouse model

Ethnobotanical relevance: : In previous in vitro bioassay studies, Populus balsamifera L (Salicaceae), a medicinal plant ethnobotanically identified from the traditional pharmacopoeia of the Cree of Eeyou Istchee (Eastern James Bay area of Canada), exhibited a strong anti-obesity potential by potently inhibiting adipogenesis in 3T3-L1 adipocytes. The aim of the study is to evaluate the effectiveness of this plant extract in mitigating the development of obesity and the metabolic syndrome in diet-induced obese (DIO) C57BL/6 mice. Materials and methods: Mice were subjected for eight weeks to a standard diet (CHOW), a high fat diet (HFD; DID group), or HFD to which Populus balsamifera was incorporated at 125 and 250 mg/kg. Results: The results showed that Populus balsamifera decreased in a dose-dependent manner the weight gain of whole body, retroperitoneal fat pad and liver as compared to DID controls and reduced the severity of hepatic macrovesicular steatosis and triglyceride accumulation. This plant extract also decreased glycemia in the second half of the feeding period and improved insulin sensitivity by diminishing insulin levels and the leptin/adiponectin ratio, as well as augmenting adiponectin levels. These effects were associated with slightly but significantly reduced food intake with 250 mg/kg Populus balsamifera as well as with an increase in energy expenditure (increase in skin temperature and increased expression of uncoupling protein-1; UCP-1). Data also suggest other mechanisms, such as inhibition of adipocyte differentiation, decrease of hepatic inflammatory state and potential increase in hepatic fatty acid oxidation. Conclusion: Taken together, these results confirm the potential of Populus balsamifera as a culturally adapted therapeutic approach for the care and treatment of obesity and diabetes among the Cree. (C) 2012 Elsevier Ireland Ltd. All rights reserved.