INS and metabolic syndrome: AMP-activated protein kinase (AMPK) is a key regulator of cellular glucose and lipid metabolism, and its activation enhances insulin sensitivity in various tissues, promotes energy generation (glucose transport and fatty acid oxidation), inhibits energy expenditure (lipid synthesis, protein synthesis, and gluconeogenesis), inhibits fatty acid release in adipocytes, promotes fatty acid degradation, and thus plays a role in the therapeutic effect on metabolic syndrome, diabetes, etc. (Daval et al., 2006).