Individual and combined effects of exercise training and dietary fat on myocardial triglycerides in obese mice

Epicardial Fat;Myocardial Triglycerides;Exercise

Cortez, Filand ; Wilund ; Kenneth R.

关键词: Epicardial Fat;    Myocardial Triglycerides;    Exercise;   

Others  :  https://www.ideals.illinois.edu/bitstream/handle/2142/30944/Cortez_Filand.pdf?sequence=1&isAllowed=y

美国|英语

来源: The Illinois Digital Environment for Access to Learning and Scholarship

【 摘 要 】

Visceral adipose tissue has been suggested to have a stronger association with disease than subcutaneous adipose tissue.This is primarily due to its inflammatory nature.Epicardial adipose tissue is a type of visceral fat located on the exterior of the heart.Recent evidence suggests an association between atherosclerosis, epicardial fat, and hepatic triglyceride deposition.PURPOSE -The purpose of this study was to determine the individual and combined effects of endurance exercise training and changes in dietary fat intake on myocardial triglyceride, a marker of epicardial fat, as well as hepatic triglycerides, another visceral fat depot implicated in CVD and diabetes risk, in a mouse model of dietary induced obesity. METHODS – Male c57BL/6 mice (n=73) fed a 45% high-fat diet for 6-weeks to induce obesity were randomly assigned into four groups: exercise high-fat, exercise low-fat, sedentary high-fat, sedentary low-fat.Exercise intervention consisted of treadmill running for 5 days/week, 40 min/day, at an intensity of 65-70% VO2max for 12 weeks.After the 12 weeks, animals were sacrificed and both hearts and liver were removed.Using a triglyceride assay, myocardial and liver triglycerides levels were determined.RESULTS – Exercise training significantly lowered liver triglycerides in both high fat and low fat fed mice(p < 0.001 for both groups).However, dietary fat intake did not have a significant effect on liver triglycerides within activity groups.Exercise training also lowered myocardial triglycerides in mice fed a high fat diet (p = 0.005), but had no effect on myocardial triglycerides in mice fed a low fat diet.By contrast, mice fed a low fat diet had significantly lower myocardial triglycerides than high fat fed mice, regardless of activity group (p < 0.01 for both groups). CONCLUSION – Exercise training can attenuate epicardial/myocardial and hepatic fat accumulation in obese mice.Low fat diets can decrease myocardial fat accumulation in obese mice.