SLC2A4 and type 2 diabetes mellitus: Transcriptome analysis indicated that FYGL could increase the expression of thermogenesis genes (Cd81 and Slc25a4) in beige adipose, as indicated by the transition from blue to red in Fig. 4B. Furthermore, FYGL and metformin increased the mRNA levels of Akt2 (encoding AKT2 [51]) and Slc2a4 (encoding GLUT-4, glucose transporter-4 [52]), as shown in Fig. 3B. Deficiency of AKT2 and GLUT-4 leads to type 2 diabetes and insulin resistance [51, 53].