Calcitriol modulates cholesteryl ester transfer protein (CETP) levels and lipid profile in hypercholesterolemic male rabbits: A pilot study.

Vitamin D3 efficacy against cardiovascular disease prevention has been reported in many experimental studies. We aimed to investigate the effect of the calcitriol or active form of Vitamin D3 (1, 25(OH) 2D3) on serum cholesteryl ester transfer protein (CETP) levels in a rabbit model of atherosclerosis. New Zealand white male rabbits were fed with 1% cholesterol diet and randomly assigned into two groups (n = 6). The case group was administrated with 50000 calcitriol (IU/kg/per wk) and the control group which administrated with calcitriol solvent (sesame oil) for 2 months. Then, after two months the lipid profile, CETP and 25OHD3 levels were measured. The serum concentration of CETP was increased after treatment with calcitriol in case group as compared to the control group (41.75 ± 3.19 vs. 34.5 ± 2.3, ng/ml, P < 0.05). We also observed higher levels of the 25OHD3 in the calcitriol group at the 1 month (16.3 ± 1.64 vs. 12.8 ± 1.33 ng/ml) and the 2 month (19.5 ± 2.14 vs. 12.5 ± 1.25 ng/ml) as compared with the control group. the significant increase in the level of HDL-C was observed in the case group than the control group (P < 0.01). In addition, serum levels of LDL- Cholesterol (LDL-C), Triglyceride (TG) were reduced after assessment at 1 and 2 month after administration of calcitriol. Our research indicated the significant anti-atherogenic effects of calcitriol in the rabbit model of atherosclerosis. However, increased in CETP levels by calcitriol may know as an additional way, which interfere with the anti-atherogenic effects of calcitriol.