Effect of cold exposure on browning of white adipose tissues in mice fed with high fat diet / 中国药理学通报

ABSTRACT

Aim: To observe the effect of cold exposure on browning of white adipose tissues in mice fed with high fat diet. Methods: Male 8-week-old C57BL/6J mice were randomly divided into HFD + 5 °C group and HFD + RT group, after 8 weeks of high-fat diet. Male 8-week-old C57BL/6J mice were randomly divided into normal + 5 °C group and normal + RT group, after 8 weeks of normal diet. Each group of mice were intervened for 2 h at different temperatures in the same time period for 8 weeks. Parameters, including body weight, food intake, inguinal white adipose tissue (iWAT) mass, brown adipose tissue (BAT) mass, blood glucose, blood lipids, leptin, adiponectin, adipose tissue pathology and in situ expression of uncoupling protein 1(UCP1) and prohibitin protein (PHB) in iWAT and BAT. Results: Compared with HFD + RT group, cold exposure not only significantly reduced body weight, blood glucose, iWAT weight/body weight ratio, TC, TG, LDL-C and leptin, but also increased food intake and BAT weight in high-fat diet mice. HE staining showed that iWAT and BAT cells became smaller and had multiple compartments. The iWAT had a browning trend. Immunohistochemistry showed that UCP1 and PHB protein in iWAT and BAT significantly increased. Conclusions: Cold exposure can counteract the weight gain caused by a high-fat diet, which may be related to the activation of brown adipose tissue and the induction of browning of white adipose tissues, increasing heat production and reducing white fat accumulation.