Research has found that the intraperitoneal injection of Apelin-13 (200 μg/kg/day, 4 weeks) can enhance the expression of Apelin-12, glucose transporter 4 (GLUT4), and AMP-activated protein kinase (AMPK) α-2 in the serum, as well as in the myocardial and aortic tissues of rats with DM. This evidence concerns the gene APLN and diabetes mellitus.