Time‐dependent effect of conjugated linoleic acid‐induced body fat loss and lipolysis in coconut oil fed mice

Abstract

Dietary conjugated linoleic acid (CLA) causes a body fat loss that is enhanced when mice are fed coconut oil (CO). The objective was to determine if there is a time-dependent effect of CLA feeding on lipolysis. Male mice (ICR; n=80; 3wk-old) were fed 7% SO or CO diets for 6wk then 0 or 0.5% CLA for 3, 7, 10 or 14d. A body fat index (BFI) was calculated and lipolysis was determined ex vivo by NEFA and glycerol release from adipose tissue. The relative expression of perilipin and phosphorylated perilipin (P-perilipin) were determined by western blotting. The BFI was reduced by CO on d7 (P<0.01), and by both CLA (P<0.05) and CO (P<0.05) on d14. NEFA release was increased by CLA in CO-fed mice (1.84 vs 7.93 μmol/g; P<0.01) but not in SO-fed mice (1.64 vs 2.03 μmol/g) on d7 but on d14 CLA increased NEFA release in both CO (2.83 vs 6.16 μmol/g) and SO-fed mice (2.01 vs 4.99 μmol/g). Glycerol release was increased by CLA in CO-fed mice but not in SO-fed mice on d3 and d7 (P<0.05). P-perilipin was not altered by diet but total perilipin tended to be increased by CLA in CO-fed mice (P=0.055) on d7. Therefore CLA-induced lipolysis may occur more rapidly in CO vs SO-fed mice but appears to be transitory.