Inhibition of cholesterol biosynthesis in freshly isolated blood mononuclear cells from normolipidemic subjects and hypercholesterolemic patients treated with bezafibrate.

Bezafibrate was given for 15 days at a dose of 200 mg t.i.d. to 4 normolipidemic subjects, to 5 patients with putative heterozygous familial hypercholesterolemia, and to 6 patients with primary hypercholesterolemia of the non-familial type. At the end of the treatment, the rate of incorporation of labelled acetate into non-saponifiable lipids in freshly isolated blood mononuclear cells decreased in all subjects. On the average, acetate incorporation decreased by 31% in cells from normolipidemic subjects, 41% in cells from familial, and 45% in cells from non-familial hypercholesterolemia patients. Results of the present study suggest that the lowering effect of bezafibrate on serum cholesterol is mainly due to the inhibition of cholesterol synthesis through the suppression of HMG-CoA reductase as was demonstrated in rat hepatocytes and in cultured human blood mononuclear cells.