Trans-8,cis-10+cis-9,trans-11-conjugated linoleic acid mixture alters body composition in Syrian golden hamsters fed a hypercholesterolaemic diet

Abstract

The effectiveness of conjugated linoleic acid (CLA) as a weight-loss nutraceutical continues to be debatable, suggesting that there may be value in exploring the physiological effects of the lesser-known isomers. The effects of the minor isomer,trans-8,cis-10 (t8,c10)-CLA, in the form of an equimolar mixture with thecis-9,trans-11 (c9,t11) isomer, on body weight and body composition, circulating glucose and lipid concentrations, and liver weights were studied in sixty male Syrian golden hamsters. Animals were randomised to receive for 28 d a semi-purified, hypercholesterolaemic diet (5 % dietary fat and 0·25 % cholesterol) supplemented at the 2 % level with either thet8,c10+c9,t11-CLA mixture,c9,t11-CLA ortrans-10,cis-12 (t10,c12)-CLA replacing lard and safflower-seed oil (control). Results show that compared with control, thet8,c10+c9,t11-CLA mixture andt10,c12-CLA-fed animals had lower (P < 0·0001) fat mass following supplementation. Animals consumingt10,c12-CLA also possessed higher lean mass compared with control andc9,t11-CLA groups (P < 0·001). However, the livers of these animals were larger (P < 0·0001) compared with those in the control and other CLA groups. Body weights of the hamsters did not differ across the experimental groups. CLA treatments had no effect on serum glucose or lipid profile, except for inducing higher (P < 0·05) non-HDL-cholesterol concentration witht10,c12-CLA compared with thec9,t11 isomer. Overall, these results indicate that in male hamsters fed a hypercholesterolaemic diet, thet8,c10+c9,t11-CLA mixture does not have an impact on blood lipid profile, but is able to effectively reduce fat mass, without incurring an accompanying liver enlargement.