INS and type 2 diabetes mellitus: The liver, as a 'metabolic workhorse', performs a diverse array of biochemical functions necessary for whole-body metabolic homeostasis, which is related to alterations in glucose, fatty acid, bile acid, insulin resistance, lipoprotein metabolism and inflammation in obese people, and is a major target of clinical anti-type 2 diabetes mellitus (T2DM) drugs like metformin (Foretz, et al., 2019; Yang, et al., 2018).