INS and type 2 diabetes mellitus: Reduced glucose transporter 4 (GLUT4) in subcutaneous adipocytes, impaired insulin clearance in the liver, mitochondrial functional abnormalities, and serine kinase stimulation in the mitogen-activated protein kinase/extracellular signal-regulated kinase (MAPK-ERK) pathway are some alternate mechanisms of IR that can lead to an increased risk of T2DM [18].