[Metformin reduces the signs of sarcopenia in old OXYS rats].

The increasing prevalence of sarcopenia (with the gradually aging population) necessitates the development of effective prophylactic strategies. As promising geroprotectors that comprehensively influence the processes of aging, mimetics of caloric restriction are being actively studied, for example, the antidiabetic agent biguanide Metformin (MF). We tested the influence of MF on the signs of sarcopenia in senescence-accelerated OXYS rats during oral administration (100 or 300 mg per kilogram of body weight per day, with feed) from age 19 to 24 months: the period when the signs of sarcopenia are present. We analyzed the effects of MF on muscular strength of the rats and on structural and functional parameters of skeletal muscle by means of light microscopy. MF slowed down the age-related atrophy of muscle fiber bundles because it slowed the necrosis of some fibers, sclerotic changes in skeletal muscle, and hypertrophy of connective tissue of the perimysium (with a greater effect on the endomysium). MF also substantially improved the blood supply and metabolism in the fibers. As a result of MF treatment, the structure of skeletal muscle of OXYS rats approached that of Wistar rats (healthy control) in terms of qualitative and quantitative parameters; this improvement increased the muscle strength of OXYS rats and abrogated the weight loss that is characteristic of old age.