FNDC5 and type 2 diabetes mellitus: However, our study found no correlation between betatrophin and irisin in women with newly diagnosed T2DM, which might be due to the following reasons: exercise involved in irisin expression and secretion was not evaluated in this study, and diabetes mellitus is a group of metabolic diseases influenced by many factors (such as obesity, blood lipids, insulin, dietary and so on), and we only excluded the confounding factor of obesity in our study.