Study of the effect of metformin in small doses on the behavioral characteristics and biochemical parameters of rats

Introduction. Metformin is an oral antidiabetic drug with a known efficacy and safety profile. Currently, there is more data on the effect of metformin on central nervous system functions in small doses, not associated with hypoglycemic effects to influence the aging process and concomitant age-related diseases. However, there is insufficient information about the effect of metformin on the behavioral characteristics and cognitive functions of a healthy body.

Aim. Investigation of the effect of metformin in small doses on behavioral characteristics and some biochemical parameters of blood serum (glucose, cholesterol, and low-density lipoprotein (LDL) levels) in rats.

Materials and methods. The study was performed on 72 male rats weighing 200–250 g of the Wistar line. Behavioral testing was performed after 30 days of metformin administration at doses of 35 and 70 mg/kg. The «T-maze test» installation was used to study the effects on learning and memory processes, and the «Water maze test» was used to study spatial memory. The «Elevated plus-maze test» and «Extrapolation escape task» settings were used to assess the effect of metformin on anxiety in rats. «The Rotarod» complex was used to assess the effect on the physical activity of rats. The biochemical parameters of rat blood serum were measured using an automatic DIRUI CS-300B biochemical analyzer.

Results and discussion. It was found that 30-day administration of metformin in both doses (35 and 70 mg/kg) improved learning and memory processes in «T-maze test» test (p < 0.05). In addition, administration of metformin in small doses (35 and 70 mg/kg) It contributed to the development of the anxiolytic effect in «Elevated plus-maze» test and «Extrapolation escape task» tests (p < 0.05). It was shown that the administration of metformin (70 mg/kg) improved muscle endurance in «Rotarod» test (p < 0.05) against the background of unchanged glucose levels.

Conclusion. The results of the conducted studies determine the direction of further research on the possibility of using metformin in small doses that do not have a hypoglycemic effect for the correction of anxiety and cognitive disorders in pathological conditions of the CNS, including in the process of physiological aging.

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