Blood Lipid Distribution, Aortic Cholesterol Concentrations, and Selected Inflammatory and Bile Metabolism Markers in Syrian Hamsters Fed a Standard Breeding Diet

Abstract

Hamsters are often used to determine the effects of various dietary ingredients on the development of cardiovascular disease (CVD). The study was conducted to obtain baseline data on CVD risk factors and mRNA expression of selected genes in hamsters fed a standard maintenance diet (STD) for 24 wk, beginning when animals were 7 wk old. Plasma triacylglycerol and aortic cholesteryl ester concentrations did not significantly change during the study. Total plasma cholesterol (75.9-127.9 mg/dL), LDL- (3.2-12.2 mg/dL), and HDL- (53.8-98.9 mg/dL) cholesterols increased over the 24wk study. Aortic total cholesterol increased from 9.72 to 12.20 μg/mg protein, whereas aortic cholesteryl ester, a measure of atherosclerosis development, was less than 0.18 μg/mg protein throughout the study. The expression of hepatic endothelin 1, peroxisome proliferator-activated receptor α, and hepatic cholesterol 7-α-hydroxylase mRNA did not change throughout the study, indicating that fatty acid β-oxidation and cholesterol metabolism remained consistent. The mRNA expression of ATP-binding cassette, subfamily B member 11 increased between wk 0 and 8 but then remained unchanged, suggesting increased requirements for cholesterol in early growth. These results indicate that the consumption of a STD does not increase atherosclerotic disease risk factors in golden Syrian hamsters through 31 wk of age.

Figure 1.

Composition of the standard diet.

Figure 2.

Sequences and annealing temperatures of PCR primers

Figure 3.

Hepatic expression of endothelin 1 (ET1) mRNA in hamsters (n = 6) that consumed a standard diet for 24 wk. Means did not differ significantly (P > 0.05).

Figure 4.

Hepatic expression of peroxisome proliferator-activated receptor α (PPARα) mRNA in hamsters (n = 6) that consumed a standard diet for 24 wk. Means did not differ significantly (P > 0.05).

Figure 5.

Hepatic expression of cholesterol 7-α-hydroxylase (CYP7A1) mRNA in hamsters (n = 6) that consumed a standard diet for 24 wk. Means did not differ significantly (P > 0.05).

Figure 6.

Hepatic expression of ATP-binding cassette subfamily B member 11 (ABCB11) mRNA in hamsters (n = 6) that consumed a standard diet for 24 wk. *, Value is significantly greater (P < 0.05) than those at other time points.