Conjugated linoleic acid isomer effects in atherosclerosis: Growth and regression of lesions

Abstract

Conjugated linoleic acid (CLA), a mixture of positional and geometric isomers of octadecadienoic acid, has been shown to inhibit experimentally induced atherosclerosis in rabbits and also to cause significant regression of pre-established atheromatous lesions in rabbits. The two major CLA isomers (cis9,trans11 and trans10,cis12), now available at 90% purity, have been tested individually for their anti-atherogenic or lesion regression potency. The two major isomers and the mixture were fed for 90 d to rabbits fed 0.2% cholesterol. Atherosclerosis was inhibited significantly by all three preparations. The two CLA isomers and the isomer mix were also fed (1.0%) as part of a cholesterol-free diet for 90 d to rabbits bearing atheromatous lesions produced by feeding an atherogenic diet. A fourth group was maintained on a cholesterol-free diet. On the CLA-free diet atherosclerosis was exacerbated by 35%. Reduction of severity of atheromatous lesions was observed to the same extent in all three CLA-fed groups. The average reduction of severity in the three CLA-fed groups was 26 +/- 2% compared with the first control (atherogenic diet) and 46 +/- 1% compared with the regression diet. Insofar as individual effects on atherosclerosis were concerned, there was no difference between the CLA mix and the cis9,trans11 and trans10,cis12 isomers. They inhibit atherogenesis by 50% when fed as a component of a semipurified diet containing 0.2% cholesterol; and when fed as part of a cholesterol-free diet, they reduce established lesions by 26%. Reduction of atheromata to the observed extent by dietary means alone is noteworthy.

Adverse effects of conjugated alpha-linolenic acids (CLnA) on lipoprotein profile on experimental atherosclerosis in hamsters

“…Similar data were also reported using hamsters (Nicolosi et al, 1997;Gavino et al, 2000;Wilson et al, 2000 andDorfman et al, 2003). CLA may also decrease the formation of fatty streaks in hamsters and rabbits (Lee et al, 1994;Kritchevsky et al, 2004) and may help to attenuate atherosclerosis by inducing apoptosis in the atherosclerotic lesion in mice (Toomey et al, 2006). However, a recent study on hamsters reported that there may be an isomer-dependent CLA effect in this rodent model (Macarulla et al, 2005).…”

“…For example, in rabbits, Lee et al (1994) demonstrated that a mixture of CLA isomers reduces both low-density lipoprotein (LDL) cholesterol and arterial lipid accumulation. These effects were also later shown in rabbits fed a CLA mixture or single CLA isomers (such as RA or 18:2 trans-10, cis-12) provided in a semi-purified diet (Kritchevsky et al, 2004). Similar data were also reported using hamsters (Nicolosi et al, 1997;Gavino et al, 2000;Wilson et al, 2000 andDorfman et al, 2003).…”

Reporting of trans-fat on labels of Brazilian food products

“…Lambert (33) reported that natural and man-made trans-fats have different structures and functions and distinct effects on blood lipids: natural trans-fat is beneficial to health (34)(35)(36)(37)(38) while man-made trans-fat is not. In the present study, none of the dairy products made claims of no trans-fat on the packaging.…”

Incorporation of conjugated linoleic acid (CLA) and α-linolenic acid (LNA) in pacu fillets

“…Among the health benefits attributed to the CLA, anticarcinogenesis (Ha et al, 1987;Ip et al, 1996), reduction in the development of arteriosclerosis (Chouinard et al, 1999;Kritchevsky et al, 2004), immunomodulation (Cook & Pariza, 1998), and the capacity to change lipid metabolism in humans (Gaullier et al, 2004) stand out.…”