In chronic liver disease, hepatic stellate cells (HSCs) are activated, highly proliferative and produce excessive amounts of extracellular matrix, leading to liver fibrosis. Elevated levels of toxic reactive oxygen species (ROS) produced during chronic liver injury have been implicated in this activation process. Therefore, activated hepatic stellate cells need to harbor highly effective anti-oxidants to protect against the toxic effects of ROS.To investigate the protective mechanisms of activated HSCs against ROS-induced toxicity.Culture-activated rat HSCs were exposed to hydrogen peroxide. Necrosis and apoptosis were determined by Sytox Green or acridine orange staining, respectively. The hydrogen peroxide detoxifying enzymes catalase and glutathione-peroxidase (GPx) were inhibited using 3-amino-1,2,4-triazole and mercaptosuccinic acid, respectively. The anti-oxidant glutathione was depleted by L-buthionine-sulfoximine and repleted with the GSH-analogue GSH-monoethylester (GSH-MEE).Upon activation, HSCs increase their cellular glutathione content and GPx expression, while MnSOD (both at mRNA and protein level) and catalase (at the protein level, but not at the mRNA level) decreased. Hydrogen peroxide did not induce cell death in activated HSCs. Glutathione depletion increased the sensitivity of HSCs to hydrogen peroxide, resulting in 35

作者：Sandra, Dunning；Atta, Ur Rehman；Marjolein H, Tiebosch；Rebekka A, Hannivoort；Floris W, Haijer；Jannes, Woudenberg；Fiona A J, van den Heuvel；Manon, Buist-Homan；Klaas Nico, Faber；Han, Moshage

来源：Biochimica et biophysica acta 2013 年 1832卷 12期