Comparing the Protective Effect of L-carnitine, Chromium, and Vitamin D with Metformin on Kidney Parameters, Lipid Profiles, and Antioxidant Indices in Streptozotocin-diabetic Rat

Type 1 diabetes mellitus is believed to be caused by decline of insulin secretion because of destruction of the pancreatic β cell, which is characterized with symptoms such as hyperglycemia, polyuria, polydipsia, weight loss, and other symptoms. Due to the lack of sufficient data about protective effect of L-carnitine, chromium, and vitamin D as compared with metformin on biochemical indices in streptozotocin-diabetic rats, it seems necessary to determine the effects of these medications on diabetes.

Sixty Wistar rats were divided into 12 diabetic and healthy groups, and 10 groups of witness, metformin )150 mg/kg(, L-carnitine )200 mg/kg(, and chromium )2 mg/kg(, vitamin D (0.06 µg) and a group treated with simultaneous combined therapy of L-carnitine, chromium, and vitamin D. Diabetes mellitus was induced by streptozotocin. Rats with glucose levels of more than 300 mg/dL were considered as diabetic. After 30 days of treatment, the serum concentrations of renal parameters, lipid profile, malondialdehyde, and activity of superoxide dismutase were measured in the studied groups.

Malondialdehyde had a significant decrease in all diabetic groups but an increase in nondiabetic metformin and L-carnitine groups (P < 0.05). In all groups, a significant reduction of triglyceride was observed (P < 0.05). Urea increased in the diabetic metformin and chromium treatment groups, whereas in the other groups it decreased (P < 0.05). Among diabetic metformin groups, a significant increase in serum creatinine was found (P < 0.05). High-density lipoprotein also decreased in the combined group of L-carnitine, chromium, and vitamin D (P < 0.05). Cholesterol in diabetic L-carnitine, chromium treatment, and combined group showed a significant decrease (P < 0.05).

These data showed that all three drugs of L-carnitine, chromium, and vitamin D such as metformin seemed appropriate, which had the hypoglycemic, antilipidemic, and antioxidant effects.