ABSTRACT
Objective To detect steroidogenic acute regulatory protein (StAR) expression in apolipoprotein E-deficient mice at different ages and serum lipid levels. Methods Nighty-six C57BL/6J and apoE-/- mice were enrolled, which were divided into 16 groups with 6 mice per group according to age (1 day, 1, 3, 5 months), sex and genotype (C57BL/6J and apoE-/-). The serum lipid levels in C57BL/6J and apoE-/- mice were detected by commercial kits. StAR mRNA and protein expressions in liver were detected by Real-time PCR and Western blot respectively. Results ApoE-/- mice had higher LDL-cholesterol and lower HDL-cholesterol compared with C57BL/6J mice of the same age and sex. StAR mRNA and protein expressions were decreased following with aging in C57BL/6J mice. However, in apoE-/- mice with higher lipid levels, StAR mRNA and protein expressions were changed with the lipid levels other than ages. StAR mRNA and protein increased in the early stage, and then decreased with the increasement of lipids levels. Conclusions StAR could affect lipids levels and may be an effective regulator for atherosclerosis and other cardiovascular diseases.
ABSTRACT
Background Rare studies on the effect of statin on early stage of atherosclerosis have been repor- ted.Oxidative stress induced endothelial dysfunction may be the initiative factor for the development of atheroscle- rotic plague.Objective To investigate the mechanisms by which simvastatin,prevents atheroselerosis independ- ently of its lipid-lowering effect in Apolipoprotein E deficient mice.Methods Twenty-four 6 week old male apoE- deficient mice were randomly to receive placebo or simvastatin 5 mg/(kg?d)by gavage for 4 weeks.Total choles- terol(TC),super oxide dismutase(SOD),malondialdehyde(MDA)and serum nitric oxide(NO)were measured by biochemical analysis.Endothelium was observed by HE dyeing.The expression of caveolin-1 in aortic wall was detected by immunohistochemistry.Results There was no significant difference in serum TC between control and simvastatin treatment groups.Simvastatin caused less damaged endothelium(33.33% vs control's:75%,P