Saeng-Kankunbi-Tang (cYe,eayene3/4ae±currency sign) protects liver against oxidative damage through activation of ERK/Nrf2 pathway

To investigate the cytoprotective effects of Saeng-kankunbi-tang (cYe,eayene3/4ae +/- currency sign, SKT), a herbal prescription consisting of Artemisia capillaris and Alisma canaliculatum, and its underlying mechanism involved. In mice, blood biochemistry and histopathology were assessed in carbon tetrachloride (CCl4)-induced oxidative hepatic injury in vivo. The animal groups included vehicle-treated control, CCl4, SKT 500 mg/(kg day) CCl4+SKT 200 or 500 mg/(kg day). In HepG2 cell, tert-butyl hydroperoxide (tBHP) induced severe oxidative stress and mitochondrial dysfunction in vitro. The cyto-protective effects of SKT were determined by 3-(4,5-dimethylthiazol)-2,5-diphenyltetrazolium bromide (MTT) assay, flfluorescence activated cell sorting analysis and western blotting. The administration of SKT prevented liver damage induced by CCl4 in mice, by inhibition of hepatocyte degeneration and inflflammatory cell infifiltration as well as plasma parameters such as alanine aminotransferase (P < 0.01). Moreover, treatment with tBHP induced hepatocyte death and cellular reactive oxygen species production in hepatocyte cell line. However, SKT pretreatment (30-300 mu g/mL) reduced this cell death and oxidative stress (P < 0.01). More importantly, SKT inhibited the ability of tBHP to induce changes in mitochondrial membrane transition in cell stained with rhodamine 123 P < 0.01). Furthermore, treatment with SKT induced extracellular signal-regulated kinases-mediated nuclear factor erythroid-2-related factor 2 (Nrf2) activation as well as the expressions of heme oxygenase 1 and glutamate- cystein ligase catalytic, Nrf2 target genes. SKT has the ability to protect hepatocyte against oxidative stress and mitochondrial damage mediated by Nrf2 activation.