SIRT1 and Insulin resistance: SIRT1 expression is reported to be increased in the liver during fasting to upregulate the expression of gluconeogenic genes by facilitating SIRT1 binding to PGC-1α in a NAD-dependent fashion as well as by deacetylating lysine residue mainly at 13 points in PGC-1α.40 Later, SIRT1 has also been shown to deacetylate PGC-1α, thus regulating fatty acid oxidation in the skeletal muscle.79 As mentioned above, it is shown that once directly phospholyrated by AMPK, PGC-1α becomes activated and improves insulin resistance in the skeletal muscle.