The possibilities of metformin efficacy enhancment by goutweed tincture on the model of complicated dyslpidemia

Abstract

Introduction. Numerous ways of obesity overcoming are under consideration now. In this context the role of the phytotherapy may be rethinked. Substances of herbal origin with highly specific mechanisms of action (from leptin sensitezers to PPAR agonists) were isolated from the herbal raw material. The other way is to combine herbal drugs with the conventional antihyperglycemic medicines enhancing their efficacy (with the decrease in the dose) or favourably broadening pharmacodynamics. At the same time verification of such combinations efficacy is strongly needed. Among the drugs normalizing carbohydrate and lipid metabolism, metformin attracts attention because of additional benefits (improvements in endothelial dysfunction, insulin resistance, and, possibly life extension). Our work is focused on the pharmacological study of goutweed (Aegopodium podagraria L., GW) preparations and their combinations with conventional drugs. GW tincture partially increases the efficacy of metformin: after combined use of these agents in dexamethasone-treated rats, normalizing activity of metformin in regards to glucose and lipid metabolism was manifested at respectively low dose. The aim of this study is to determine the efficacy of Aegopodium podagraria L. tincture and its combination with metformin in rats with the primary disorders of lipid metabolism. Materials and methods. Combined use of atherogenic diet with additional cholesterol and protamine sulfate administration was used. Oral glucose tolerance test was performed after the treatment with metformin, GW tincture or their combination. Lipid spectrum of blood plasma and content of lipids in the liver were determined. Results. GW tincture combined with the respectively low dose of metformin increased its efficacy in glucose tolerance test with the significant reduction in area under glucose curve. All the studied agents normalized the level of cholesterol, triglycerides and lipids in the liver but did not influence significantly on the lipid spectrum in plasma. It can be supposed that the effects of GW active substances, especially hydroxicinnamic acids and flavonoids, are directed to carbohydrate metabolism processes. Conclusion. Permissive effect of GW tincture on the action of metformin (that has been demonstrated on dexamethasone-treated animals) is confirmed in dyslipidemic animals. The mechanisms of GW tincture influence on carbohydrate metabolism and its interaction with antiobesity and antidiabetic drugs are worth further studies.