Effect of gemfibrozil on composition of lipoproteins and distribution of LDL subspecies

We studied the effect of gemfibrozil on the compositions of VLDL, LDL and distribution of LDL subspecies in type II hyperlipidemic patients. Gemfibrozil significantly lowered serum triglyceride levels in this group of patients who had normal to moderately elevated triglyceride prior to therapy. Gemfibrozil also changed the composition of VLDL by lowering its free cholesterol, cholesterol ester and raising the protein content. In contrast, no measurable changes in LDL chemical composition were found following gemfibrozil therapy. Changes in LDL, however, can be detected using ultracentrifugal and electrophoretic methods. Peak densities of LDL were lowered and LDL subspecies shifted to larger, slower-moving bands on gradient gel electrophoresis in patients receiving gemfibrozil treatment. These results suggest that gemfibrozil treatment resulted in qualitative changes in both VLDL and LDL even in patients with moderately elevated baseline serum triglyceride levels.