Atherosclerosis: aortic lipid changes induced by diets suggest diffuse disease with focal severity in primates that model human atheromas.

Atherosclerosis in Vervet or African Green monkeys (Cercopithecus aethiops) models the morphology and cytology of the disease of humans, and it is well established that the rate of atherogenesis in Vervets is influenced by diet. Aortic intimal concentrations of lipids and phospholipids known to be major components of atheromas were determined in female Vervets fed for 4 years on either an atherogenic (AD) or a prudent Western diet (PD). Lipid concentrations detectable microscopically as cholesterol crystals and foam cells were confirmed biochemically. In addition, the AD was associated with diffuse, invisible accumulation of lipids throughout aortic tissue to the extent that tissue with no fatty streaks or plaque (AD) contained the same or more lipids than visible fatty streaks (PD). Correlations between lipid concentrations and atherosclerosis were highly positive, which supports known correlations between aortic, plasma, and dietary lipids during atherogenesis, and validates the aortic lipid analysis. These aortic lipid concentration results imply that atherosclerosis is not confined to focal pathologic anatomy, but in terms of lipid components of the disease, it develops throughout the arterial system of Old World omnivorous primates. If the results are applicable to people, they provide new insight and emphasize the need to minimize dietary sources of atherogenic lipids.