Background. Diabetes mellitus and hyperglycemia both are independent risk factors for coronary atherosclerosis, which is a major cause of death worldwide. The aim of this study is to elucidate the effects of some hypoglycemic drugs on serum lipid profile in hyperlipidemic, non- hyperglycemic rats, and to see whether these effects are related to their hypoglycemic effects.
Materials and Methods: This study included 50 rats which have been randomly allocated into five groups, 10 for each group. One of these groups was put on normal diet, and considered as a control group, the remaining four groups were feed with fat-rich diet for eight weeks.
Before starting treatment with hypoglycemic drugs, blood samples were collected form these five groups, and serum lipid profile namely, triglycerides(TG), total cholesterol (TC), low density lipoprotein (LDL), very low density lipoproteins(VLDL), and high density lipoproteins (HDL), were measured. The results have revealed that the four groups have become hyperlipidemic. Then one group out of the four hyperlipidemic groups received distilled water, while the other three received one of the following hyperglycemic drugs: Metformin, Rosiglitazone, and Acarbose. The four groups were kept on fat-rich diet four eight weeks.
Results: 1). All three hypoglycemic agents produced a highly significant reduction in the level of TG compared to control. However, the magnitudes of reduction varied from one drug to another. 2). Metformin and Rosiglitazon produced a significant reduction in the level of total serum cholesterol (TC) compared to control . Acarbose produced non-significant reduction in the level of TC compared to control. 3). Metformin produced a highly significant reduction in the level of LDL , Rosiglitazone produced reduction in the level of LDL, however this reduction is not significant. Acarbose, on the other hand, produced a highly significant increase in the level of LDL. 4). Metformin, Rosiglitasone, and Acarbose all produced a highly significant reduction in the level of VLDL . 5). Metformin produced a highly significant increase in the level of HDL (P<0.01), while Rosiglitazone and Acarbose produced a significant reduction in the level of HDL (P<0.05).
Conclusions: Metformin reduced serum levels of Triglycerides TG, total serum cholesterol TC, low density lipoprotein LDL, and very low density lipoprotein VLDL, but increases serum level of high density lipoprotein HDL. These effects may share in decreasing the risk of atherosclerosis. Rosiglitazone reduces serum TG, TC, VLDL, and HDL levels, but has no effect on serum LDL level. Rosiglitazone therefore, should be cautiously prescribed for patients with cardiac problems. Acarbose reduces serum TG, VLDL, HDL, and increases LDL levels, but has no effect on TC. Acarbose should also be used cautiously in patient with cardiac problems. |