Effects of conjugated linoleic acid (CLA) on tissue composition parameters in a murine cachexia model

Abstract

CLA alleviates cachectic symptoms in some experimental models. In a 2x2 factorial design, 12 female 1 mo old C57BL/6 mice were injected with LP-BM5 murine retrovirus (to induce cachexia) and 12 were used as controls. Mice were fed diets containing 0 or 1.68% CLA (50/50 cis-9, trans-11 and trans-10, cis-12) (BASF AG, Germany) for 88 d. CLA increased the content (41%) and mass (14%) of carcass protein in healthy mice but had no effect on the protein yield in cachectic mice. Both CLA and cachexia markedly reduced the content (72 and 51%, respectively) and amount (83 and 60%, respectively) of carcass fat and CLA decreased carcass fat (>50%) in cachectic mice. Carcass water was increased by the main effects of cachexia and CLA, but in cachectic mice, CLA had no effect on water variables. Cachexia decreased heart weight (34%), kidney weight (29%) and increased spleen weight (94%) while CLA had no effect on these organs. CLA increased liver weight by 69% in healthy and 33% in cachectic mice and increased hepatic lipid content by 65% in healthy and 37% in cachectic mice. CLA increased the carcass and liver content of cis-9, trans-11 (<0.1 vs. 2.3% and <0.1 vs. 1.7%, respectively) and trans-10, cis-12 CLA (<0.1 vs. 1.6% and <0.1 vs. 0.5% respectively). CLA decreased 18:2 content in carcass (46%) and liver (66%) lipids but differentially regulated 20:4 levels in carcass and liver lipids (66 increase and 65% decrease, respectively). Cachexia increased the content of most LCPUFA (i.e. ≥20:2) in both carcass and liver lipids. In conclusion, CLA reduced body fat in cachectic animals but was unable to increase muscle mass as it did in healthy mice.