Pathophysiological basis of sarcopenia — a chronic complication of diabetes

Abstract

The review considers the problem of sarcopenia, a muscle weakness and loss of mass, quality and strength of skeletal muscles, which often accompanies type 2 diabetes, especially in the elderly. Recently, sarcopenia has been considered as one of the complications of diabetes, which is associated with an increase in the frequency of cardiovascular complications, the need for hospitalization, and patient mortality. The molecular mechanisms of muscle atrophy in sarcopenia are associated with a violation of the anabolic-catabolic balance in muscles and their energy supply, fatty infiltration and shifts in proteostasis (decreasing the synthesis of muscle proteins and increasing their degradation), mitochondrial dysfunction. Insulin resistance, oxidative stress, accumulation of abdominal and ectopic fat, local inflammation play a key role in the pathogenesis of both sarcopenia and dysmetabolic diabetic complications, i.e., there is a bidirectional relationship between these pathological conditions, which mutually reinforce each other’s negative consequences. According to clini­cal observations, the risk of sarcopenia in patients with diabetes is 3–4 times higher than in people without diabetes, while the presence of sarcopenia increases the risk of reduced work capaci­ty, disability, mortality, and worsening of diabetes control. These data indicate the feasibility of screening for signs of sarcopenia in patients with type 2 diabetes, especially in the older age group, using dynamic tests, as well as bone monitoring, to prevent the risk of falls and fractures. Antidiabetic therapy for such patients should include drugs that help preserve muscle and bone tissue (have an anabolic effect), do not increase the risk of hypoglycemia and gastrointestinal disorders. According to the literature, the safest preparations include the biguanide metformin, dipeptidyl peptidase inhibitors, and insulin. Sulfonylurea derivatives, thiazolidinediones, glucagon-like peptide-1 receptor agonists, sodium-glucose cotransporter-2 inhibitors are not recommended, as they can cause undesirable effects in weakened elderly people. Timely diagnosis of sarcopenia is important to prevent the deterioration of muscle function (through the rehabilitation of the musculoskeletal system using adaptive physical exercises and diet modification) and to improve the quality of life of patients with type 2 diabetes. In turn, improving the prevention and treatment of diabetes in the early stages can also help prevent the development of sarcopenia and its complications.

Keywords

• sarcopenia
• diabetes
• insulin resistance
• hypoglycemic therapy
• review