Copper ions stimulate the proliferation of hepatic stellate cells via oxygen stress in vitro
This study examined the effect of copper ions on the proliferation of hepatic stellate cells (HSCs) and the role of oxidative stress in this process in order to gain insight into the mechanism of hepatic fibrosis in Wilson’s disease. LX-2 cells, a cell line of human HSCs, were cultured in vitro and treated with different agents including copper sulfate, N-acetyl cysteine (NAC) and buthionine sulfoximine (BSO) for different time. The proliferation of LX-2 cells was measured by non-radioactive cell proliferation assay. Real-time PCR and Western blotting were used to detect the mRNA and protein expression of platelet-derived growth factor receptor β subunit (PDGFβR), ELISA to determine the level of glutathione (GSH) and oxidized glutathione (GSSG), dichlorofluorescein assay to measure the level of reactive oxygen species (ROS), and lipid hydroperoxide assay to quantify the level of lipid peroxide (LPO). The results showed that copper sulfate over a certain concentration range could promote the proliferation of LX-2 cells in a time- and dose-dependent manner. The effect was most manifest when LX-2 cells were treated with copper sulfate at a concentration of 100 μmol/L for 24 h. Additionally, copper sulfate could dose-dependently increase the levels of ROS and LPO, and decrease the ratio of GSH/GSSG in LX-2 cells. The copper-induced increase in mRNA and protein expression of PDGFβR was significantly inhibited in LX-2 cells pre-treated with NAC, a precursor of GSH, and this phenomenon could be reversed by the intervention of BSO, an inhibitor of NAC. It was concluded that copper ions may directly stimulate the proliferation of HSCs via oxidative stress. Anti-oxidative stress therapies may help suppress the copper-induced activation and proliferation of HSCs.
Key wordscopper ions hepatic stellate cells oxidative stress hepatic fibrosis
Unable to display preview. Download preview PDF.
- 5.Wan XH, Li YW, Luo XP. Curcumin attenuated the lipid peroxidation and apoptotic liver injury in copper-overloaded rats. Chin J Pediatr (Chinese), 2007,45(8): 604–608Google Scholar
- 9.Sun YL, Zhao JM, Li WS, et al. Clinical pathological features of child Wilson’s disease and the mechanism of hepatic fibrosis. Med J Chin PLA (Chinese), 2005,30(4): 300–302Google Scholar
- 11.Tian Y, Yang X, Jiang YF, et al. 4 cases of fulminant Wilson’s disease: the clinical features and treatments. Chin J Hepatol (Chinese), 2010,18(9):717–718Google Scholar
- 16.Urtasun R, Nieto N. Hepatic stellate cells and oxidative stress. Rev Esp Enferm Dig, 2007,(4):223–230Google Scholar