The mechanisms of type 2 diabetic skeletal muscle atrophy and the effects of commonly used hypoglycemic drugs: a review / 药学学报

ABSTRACT

Type 2 diabetes is a hypermetabolic disease characterized with disorders of glucose/lipid metabolism, absolute or relative lack of insulin, and can induce skeletal muscle atrophy. Hyperglycemia, hyperlipidemia, insulin resistance, and abnormal release of inflammatory factors can lead to abnormal signal transduction in skeletal muscle, thus make protein synthesis and degradation imbalance and eventually causing muscle atrophy. Under normal conditions, insulin-like growth factor 1 (IGF-1)/insulin can activate phosphoinositide 3-kinase (PI3K)/protein kinase B (AKT). AKT not only increases protein synthesis through mammalian target protein of rapamycin (mTOR), but also phosphorylates forkhead box O (FoxO) transcription factor and then inhibits the transcription of several ubiquitin ligases (such as MAFbx/atrogin-1 and MuRF1), or autophagy related genes. The weakened IGF-1/PI3K/AKT pathway in type 2 diabetes is an important factor leading to skeletal muscle atrophy. Studies have shown that the commonly used anti-type 2 diabetic drugs have different effects in regulating the synthesis and degradation of skeletal muscle protein. Studies reported that drugs with effect of anti-diabetic muscle atrophy include thiazolidinediones, glucagon-like peptide analogs, glucose-sodium cotransporter 2 inhibitors, etc.; drugs that are still in controversial or even promote skeletal muscle atrophy include metformin, and some sulfonylurea or non-sulfonylurea insulin secretagogues. This article overviewed and analyzed the currently commonly used drugs for type 2 diabetes and summarized the related mechanisms, with the aim to provide references for the rational applications of drugs for type 2 diabetes.