Antidiabetic Drugs in Combination with Hydroxychloroquine Improve Glycemic Control in Alloxan Induced Diabetic Rats

Worldwide prevalence of diabetes mellitus has become an issue of great concern in current decades. This life threatening disease is associated with worsening of glycemic control and progressive metabolic dysfunctions. Objective: Current study aimed to investigate the effect of hydroxychloroquine (HCQ) as an adjunct to glibenclamide or metformin on glycemic control in alloxan induced diabetic rats. Methods: HCQ was combined separately with two conventional anti-diabetic drugs; glibenclamide and metformin. At first, alloxan (120 mg/kg) induced diabetic rats were treated with single dose of metformin (850 mg/70 kg BW), glibenclamide (10 mg/70 kg BW) and HCQ (300 mg/70 kg BW) intraperitoneally once daily for two weeks. Then non fixed dose combinations of glibenclamide (5 mg/70 kg BW) with HCQ (150 mg/70 kg BW) and metformin (425 mg/70 kg BW) with HCQ (150 mg/70 kg BW) were injected along with those of the three drugs alone once daily for four weeks. Results: In alloxan induced diabetic rats, glibenclamide, metformin and their combination therapies reduced blood glucose level significantly but combination therapies are the most effective. Glibenclamide or metformin in combination with HCQ also significantly (P < 0.05) reduced the elevated levels of total cholesterol, triglycerides, and low density lipoprotein cholesterol (LDL-C) level and increased high density lipoprotein cholesterol (HDL-C) level. Moreover, HCQ potentiates the liver glycogen synthesis of metformin or glibenclamide. Conclusion: Outcomes of this investigation indicate that combination of glibenclamide or metformin with HCQ improves glycemic control and provides additional metabolic benefits, not achieved with either glibenclamide or metformin alone.