MCFAs Induced Differentiation And Proliferation Of Brown Adipocytes And Their Roles In Obesity Control

Objective1. To investigate the effect of six kinds of oil mixed with MCFAs on body fat and blood lipids in C57BJ/6L obese mice induced by high fat diet.2. To investigate the effect of MCFAs on body fat and blood lipids in C57BJ/6L obese mice with interscapular brown adipose tissue depletion.3. To investigate the effect of MCFAs on differentiation and proliferation of brown adipocytes in C57BL/6J obese mice induced by high fat diet.Methods1. One hundred and five obese mice were divided into 7 groups, and fed high fat diet with six kinds of oil mixed with MCFAs or high fat diet with soybean oil for 16 weeks,respectively. Body weight, body fat mass, Lee’s index, blood lipids, fat accumulation in liver and size of white adipocytes were recorded and measured.2. Thirty obese mice with interscapular brown adipose tissue depletion were divided into 2 groups, and fed high fat diet with MCT or high fat diet with LCT for 12 weeks, respectively.Body weight, body fat mass, blood lipids, fat accumulation in liver, size of white adipocytes,and mRNA expression of UCP1 in abdominal subcutaneous adipose tissue were recorded and measured.3. Thirty obese mice were divided into 2 groups, and fed high fat diet with MCT or high fat diet with LCT for 12 weeks, respectively. Body weight, body fat mass, blood lipids,micro-PET imaging of BAT, and mRNA expression and protein expression of UCP1, BMP7,CIDEA, PRDM16, Cebp-alpha, Cebp-beta, Dio2, Fabpl, Fabp3, Fabp4, FOXC2, Gyk,PPAR-alpha, PPAR-gamma, PGC1-alpha, PGC1-beta, COX2 in brown adipose tissue and abdominal subcutaneous adipose tissue were recorded and measured.Results1.After 16 weeks, significant decreases in body weight, body fat mass, Lee’s index, blood triglyceride and total cholesterol levels, fat accumulation in liver and size of white adipocytes were observed in six kinds of oil mixed with MCFAs groups as compared with soybean oil group (P<0.05).2. After 12 weeks, no significant differences in body weight, body fat mass, blood lipids, fat accumulation in liver and size of white adipocytes in obese mice with interscapular brown adipose tissue depletion were noted between MCT and LCT groups (P>0.05). Greater increases in mRNA expression of UCP1 in abdominal subcutaneous adipose tissue was observed in MCT group than in LCT group (P<0.05).3. After 12 weeks, significant decrease in body weight, body fat mass and blood triglyceride levels was observed in MCT group as compared with LCT group (P<0.05). Greater increases in brown fat mass and metabolic activity (micro-PET) were observed in MCT group than in LCT group (P<0.05). Greater increases in mRNA expression and protein expression of UCP1, CIDEA, Fabp4, PPAR-gamma, PRDM16, BMP7 in BAT were observed in MCT group than in LCT group (P<0.05). Greater increases in mRNA expression of PGC1-alpha, FOXC2, COX2, Dio2, PGC1-beta, PPAR-alpha, CEBP-alpha,CEBP-beta in BAT were observed in MCT group than in LCT group (P<0.05). Greater increases in mRNA expression and protein expression of UCP1, CIDEA, Fabp4,PGC1-alpha, PPAR-gamma, PRDM16, FOXC2, BMP7 in abdominal subcutaneous adipose tissue were observed in MCT group than in LCT group (P<0.05). Greater increases in mRNA expression of COX2, Fabp1, Fabp3, Dio2, Gyk, PGC1-beta, PPAR-alpha,CEBP-alpha, CEBP-beta in abdominal subcutaneous adipose tissue were observed in MCT group than in LCT group (P<0.05).Conclusion1. Oil mixed with 10%-16% MCFAs can effectively reduce body weight, body fat accumulation and blood lipids levels of obese mice.2. BAT is an important target organ that MCFAs reduce body weight, body fat accumulation and blood lipids levels of obese mice.3. MCFAs can promote the differentiation, proliferation of BAT, and enhance the function of BAT, and promote the white fat browning.