A Translational Model for Diet-related Atherosclerosis: Effect of Statins on Hypercholesterolemia and Atherosclerosis in a Minipig.

Models of atherosclerosis are used in preclinical studies but often fail to translate to humans. A model that better reflects human atherosclerosis is necessary. We recently engineered the ExeGen™ low-density lipoprotein receptor (LDLR) miniswine, in which the LDL receptor gene is modified to drive hypercholesterolemia and atherosclerosis, and showed diet-related exacerbation of these phenotypes. Five groups of animals, either wild type (+/+) or heterozygous (+/-), were fed either a normal or high-fat diet for 6 months. One group of heterozygous pigs fed a high-fat diet was also administered atorvastatin at 3 mg/kg/day. Clinical chemistry and anatomic pathology parameters were measured biweekly and at termination. The high-fat diet resulted in increased adiposity and interspersion of adipocytes within the salivary glands. The heterozygous pigs on the high-fat diet gained more weight and had significant increases in total cholesterol, high-density lipoprotein, and LDL compared to wild-type animals or heterozygous animals fed a normal diet. Atorvastatin attenuated these parameters, indicating the statin had a beneficial effect, even in a high-fat diet scenario. Atorvastatin treatment also reduced the intensity of Oil Red O staining in pigs on high-fat diet. Atorvastatin-related amelioration of several indices of cardiovascular pathophysiology in this model underscores its utility for drug discovery.