Objective To investigate activation of brown adipose tissue （BAT） stimulated by medium-chain triglyceride （MCT）. Methods 30 Male C57BL/6J obese mice induced by fed high fat diet （HFD） were divided into 2 groups, and fed another HFD with 2% MCT or long-chain triglyceride （LCT） respectively for 12 weeks. Body weight, blood biochemical variables, interscapular brown fat tissue （IBAT） mass, expressions of mRNA and protein of beta 3-adrenergic receptors （β3-AR）, uncoupling protein-1 （UCP1）, hormone sensitive lipase （HSL）, protein kinase A （PKA）, and adipose triglyceride lipase （ATGL） in IBAT were measured. Results Significant decrease in body weight and body fat mass was observed in MCT group as compared with LCT group （P〈O.05） after 12 weeks. Greater increases in IBAT mass was observed in MCT group than in LCT group （P〈O.05）. Blood TG, TC, LDL-C in MCT group were decreased significantly, meanwhile blood HDL-C, ratio of HDL-C/LDL-C and norepinephrine were increased markedly. Expressions of mRNA and protein of β3-AR, UCP1, PKA, HSL, ATGL in BAT were greater in MCT group than in LCT group （P〈O.05）. Conclusion Our results suggest that MCT stimulated the activation of BAT, possible via norepinephrine pathway, which might partially contribute to reduction of the body fat mass in obese mice fed high fat diet.
