Effect of the combination of metformin hydrochloride and melatonin on oxidative stress before and during pregnancy, and biochemical and histopathological analysis of the livers of rats after treatment for polycystic ovary syndrome

The aim of the present study was to analyze the effect of a combination of metformin hydrochloride and melatonin on oxidative stress together with a biochemical and histopathological analysis of the livers of Wistar rats induced with PCOS. The results indicated that a combination of the drugs was more effective in the reduction of plasmatic levels of liver enzyme alanine aminotransferase, nitric oxide and total glutathione, and decreased the inflammatory response and histopathological damage, producing results that were significantly similar to animals from the control group. A mixture of the drugs produced more effective results against liver toxicity caused by PCOS, encouraging the normalization of biochemical parameters. During pregnancy, there was reduced oxidative stress compared to monotherapeutic use of these drugs. Interestingly, the combination of the drugs caused a physiological reaction similar to responses identified in healthy rats without induction of the PCOS control group. However, the clinical and physiological effectiveness of the combination should be further explored, especially with respect to the possible side effects on offspring. [Display omitted] •Studies have documented increased oxidative stress in patients with PCOS.•It has been noted that women with PCOS have a high prevalence of liver alterations.•Liver disease in pregnancy may be pre-existing increasing the newborn mortality.•Metformin/melatonin associated reduced oxidative stress in liver in pregnant rats.•Association of metformin/melatonin normalizes hepatic biochemical parameters.