SIRT1 and injury: In addition, previous studies also indicated that quercetin can up-regulate the sirtuin 1/extracellular signal regulated kinase (SIRT1/ERK) pathway, up-regulate the expression of Bcl-2, and down-regulate the expression of cleaved caspase-3 and cleaved caspase-9 to alleviate cell apoptosis during isoniazid-induced liver injury (41, 42).