Aortic atherosclerosis in rabbits

Table I. Serum Lipids and Aortic Atherosclerosis in Rabbits fed Casein, Soy Protein, Casein Arginine, or Soy Lysine...

Shaish A, Pape M, Rea T, et al. Alcohol increases plasma levels of cholesterol diet-induced atherogenic lipoproteins and aortic atherosclerosis in rabbits. Arterioscler Thromb Vase Biol 1997 17 1091-1097. 

YAMAKOSHi J, KTAOKA s, KOGA T, ARiGA T (1999) Proanthocyanidin-rich extract from grape seed attenuates the development of aortic atherosclerosis in cholesterol-fed rabbits, Atherosclerosis, 142, 139-49. 

Nordestgaard, B.G. and Lewis, B. (1991) Intermediate density lipoprotein levels are strong predictors of the extent of aortic atherosclerosis in the St. Thomas s Hospital rabbit strain. Atherosclerosis 87, 39 6. 

The results of these studies indicated that CLA at levels of 0.1% in the diet inhibited atherogenesis and at levels of 1.0% caused significant regression of atherosclerosis in rabbits. In addition to a reduction in aortic plaque formation and modulating liver and serum lipid levels, CLA has also been demonstrated to reduce systolic blood pressure in OLETF rats, a strain developed as a model of non-insulin-dependent diabetes mellitus (NIDDM) with mild obesita (59). 

The increased levels of blood and aortic tissue malondialdehyde and chemiluminescence of polymorphonuclear leucocytes, which were associated with development of atherosclerosis in rabbits, suggest a role of reactive oxygen species in the pathogenesis of hypercholesterolemia-induced atherosclerosis (Prasad and Kalra 1993). The protection afforded by vitamin E, which was associated with a decrease in blood and aortic tissue malondialdehyde concentrations in spite of hypercholesterolemia, supports the hypothesis that reactive oxygen species are involved in the development of hy-percholesterolemic atherosclerosis. 

The pyrazolosteroid CLXXIX (stanazolol, Win-14,833) is also an anabohc agent which has been found to decrease serum hpids in man [403]. The same steroid with a Ta-SCgHg substituent (CLXXX, PS-179) has been reported to exert a prophylactic effect on aortic atherosclerosis in male rabbits fed cholesterol-coconut oil [404]. 

Beetens, J. R., Coene, M.-C., Verheyen, A., Zonnekeyn, L., and Herman, A. G., 1984, Influence of vitamin C on the metabolism of arachidonic acid and the development of aortic lesions during experimental atherosclerosis in rabbits, Biomed. Biochim. Acta 43 8273-8276. 

Mortensen A, Hansen BF, Hansen JF, et al. Comparison of the effects of fish oil and olive oil on blood lipids and aortic atherosclerosis in Watanabe heritable hyperlipidaemic rabbits. BrJ Nutr 1998 80 565-573. 

Mortensen, A., Breinholt, V., Frandsen, H., Lund, C.O., Ottesen, B., and Larsen, J.J. 2003. Dietary soy supplement reduces aortic atherosclerosis in ovariectomized Watanabe heritable hyperlip-idemic rabbits. Atherosclerosis Supplements 4, 276. 

CN125 Vas Dias, F. W., M. J. Gibney, and T. G. Taylor. The effect of polyunsatu-rated fatty acids on the n-3 and n-6 series on platelet aggregation and platelet and aortic fatty acid composi-tion in rabbits. Atherosclerosis 1982 43(2-3) 245-257. 

Rabbits fed a 0.5% cholesterol diet had atherosclerotic plaques on over 50%i of the aorta surface whereas the 0.5% cholesterol plus 40 mg lignan complex/kg body/per day reduced atherosclerosis by 34.4% (Prasad, 2005). Furthermore, the added lignan complex lowered the total cholesterol, LDL cholesterol, serum, and aortic malondialdehyde by 20%, 14%, 35%, and 58%, respectively. Unlike previous studies, the lignan enhanced HDL cholesterol by 25% and 30% in normocholesterolemic and hypercholesterolemic rabbits, respectively. Slightly higher (33% and 35%) reductions in total cholesterol and LDL cholesterol, respectively, were observed in rabbits on a 1% cholesterol diet containing 15 mg SDG/kg/day (Prasad, 1999). A 73% reduction in atherosclerosis was observed in the rabbits given the SDG diets compared to the 1% cholesterol diets. 

Kritchevsky (1999) reviewed studies conducted with colleagues, which demonstrated that dietary CLA could inhibit the development of cholesterol-induced atherosclerosis in hamsters and in rabbits. Reduction in the severity of pre-existing lesions was also noted. Recently, Kritchevsky (2003) fed rabbits a diet containing 1% of relatively pure RA. This diet significantly inhibited the formation of atherosclerotic lesions in the aortic arch and thoracic aorta, compared to a diet without RA. 

Ming-Peng et al. (1990) studied high density lipoproteins and prevention of experimental atherosclerosis in tree shrews (Tupaia belangera yunalis). In contrast to rabbits, no increased lipid deposition in aortic intima after cholesterol feeding was found in tree shrews. 

Stender, S., P.Astrup, and K.Kjeldsen. 1977. The effect of carbon monoxide on cholesterol in the aortic wall of rabbits. Atherosclerosis 28(4) 357—367. 

Fig. 3. (A) Intracellular unesterified cholesterol accumulation in a lesional foam cell. Electron micrograph of the cytoplasm of a foam cell isolated ftom an advanced aortic atherosclerotic lesion in a cholesterol-fed rabbit. The cell was treated with filipin, which forms spicules with unesterified cholesterol. Multiple spicules are observed in vesicles, shown to be lysosomes (depicted by arrows). D , neutral lipid droplet. Bar 0.5 pm. From [34]. Lab. Invest. 41 160-167. (B) Extracellular cholesterol crystals in an advanced atherosclerotic lesion. The section is from the proximal aorta of a fat-fed apolipoprotein E knockout mouse. This mouse model is often used to study atherosclerosis in vivo because the high plasma levels of remnant lipoproteins resulting from absence of apolipoprotein E leads to a much greater degree of atherosclerosis lesion development than observed in wild-type mice. The arrows depict the areas of cholesterol crystals. Reproduced with permission from the publisher.

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