Comparative study of the atherogenecity of dietary trans, saturated and unsaturated fatty acids on swine coronary arteries.

Effects of specific fatty acids (8:0,14:0, cis-18:1, trans-18:1) on plasma lipoproteins, early atherogenic potential, and LDL oxidative properties in the hamster

“…The finding that trans-18:1-and cis-18:1-fed animals had less severe atherosclerosis than the saturated 14:0 group is consistent with several animal studies (15)(16)(17)(18)(19)(20), and may be related to the lower plasma LDL-C levels of the latter relative to the former, although a recent atherosclerosis study in monkeys did not show a protective effect of cis-18:1 versus SFA (47). The finding that feeding trans-18:1 to hamsters was not associated with increased early atherosclerosis is consistent with some human studies of trans fatty acid intake and cardiovascular disease in humans, but not with others as reviewed by Zock and Katan (57).…”

“…Our finding that feeding TAG enriched in trans-18:1 did not significantly elevate plasma TC, VLDL-C, and LDL-C relative to cis-18:1 is in disagreement with several human studies (7)(8)(9), one rabbit study (15), and the recent hamster studies of Woollett et al (14). On the other hand, our findings of comparable plasma lipid responses between cis unsaturated fatty acids and trans-18:1 are similar to other studies in hamsters (45), rabbits (17), swine (19), and monkeys (20). While an explanation for the disparity in results is not readily apparent, one possibility is that most animal and human studies substitute the cholesterol-lowering cis unsaturated fatty acids for trans-18:1 making it difficult to determine whether the effects of trans-fatty acids on plasma lipids occur independently or are the result of reducing the dietary content of cholesterol-lowering unsaturated fatty acids.…”

“…While the plasma lipid and lipoprotein effects of trans fatty acids have been evaluated to a great degree, very few well-controlled systematic studies have been conducted to establish whether they play a role in the atherogenic process or influence other end-points associated with the development of atherosclerosis such as the oxidative susceptibility of LDL. Early studies with rabbits (15)(16)(17), swine (18,19) and vervet monkeys (20) showed no effect of trans fatty acids on atherosclerosis. However, a lack of systematic control over the fatty acid composition of the diet, as well as inconsistent demonstration of elevated plasma cholesterol, which is an essential component for inducing experimental atherosclerosis, prevented drawing meaningful conclusions from these studies.…”

Decreased aortic early atherosclerosis and associated risk factors in hypercholesterolemic hamsters fed a high- or mid-oleic acid oil compared to a high-linoleic acid oil

“…This protective finding for a MUFA-enriched diet is not supported by one study in monkeys [7], a study in LDL receptor-null, human apolipoproteinB-overexpressing transgenic mice [43] and one study in LDL receptor-deficient mice [44]. On the other hand, the antiatherosclerotic properties of MUFA-enriched diets have been demonstrated in rabbits [45][46][47][48] and monkeys [49,50], our own previous studies in hamsters [13], and in swine [51,52]. There are several possible mechanisms derived from both in vitro and in vivo studies that might explain the beneficial effects of MUFA-containing diets as they relate to early atherosclerosis.…”

Screening for malnutrition in dwelling elderly

“…As to whether TFA influence the severity of atherosclerosis in animal studies, seven different studies were reported by Nicolosi 32 in rabbits, pigs and vervet monkeys. In none of these studies there was any increase in the risk of atherosclerosis whatever was the level of TFA included in the diet (from 3.2% or 6.0% trans in the diet with 14% fat given to vervet monkeys 33 to 50% TFA in the 17% fat diet given to pigs) 34 . Thus in experimental models of atherosclerosis tested, there was little evidence that dietary TFA caused the development of atherosclerosis, even fatty streaks.…”