den Hartog Gertjan J M, Qi Shufan, van Tilburg Jonathan H O, Koek Ger H, Bast Aalt
Maastricht University, Faculty of Health, Medicine and Life Sciences, Department of Toxicology, Maastricht, The Netherlands.
Maastricht University, Faculty of Health, Medicine and Life Sciences, Department of Toxicology, Maastricht, The Netherlands.
Eur J Pharmacol. 2014 Feb 5;724:140-4. doi: 10.1016/j.ejphar.2013.12.033. Epub 2013 Dec 28.
It is generally accepted that reactive oxygen species (ROS) play an important role in the pathogenesis of liver fibrosis. ROS, however, constitute a group of species with varying properties making it likely that their contribution to the pathological mechanism varies. LX-2 hepatic stellate cells (HSCs) were exposed to superoxide anion radicals (O2(·-)) generated by xanthine and xanthine oxidase. To rule out that the activation of HSCs is due to hydrogen peroxide derived from O2(·-), control incubations with copper, zinc-superoxide dismutase and tempol were studied as well. Influx of O2(·-) activated HSCs, evidenced by the expression of α-smooth muscle actin and the secretion of transforming growth factor β1 and collagen. We further found that blockade of chloride channels with 4,4'-diisothiocyanatostilbene-2,2'-disulfonic acid (DIDS), 5-nitro-2-(3-phenylpropyl-amino) benzoic acid (NPPB) or indanyloxyacetic acid (IAA-94) prevented the increase of intracellular O2(·-) levels as well as the activation of HSCs. These findings suggest that O2(·-) is involved in the development of liver fibrosis and that entry of O2(·-), through chloride channels, in stellate cells is critical for their activation. This study provides new insight into the mechanism by which ROS induce liver fibrosis. Furthermore, our data suggest that chloride channels constitute a potential target for new anti-fibrotic drugs.
一般认为，活性氧（ROS）在肝纤维化的发病机制中起重要作用。然而，ROS是一组性质各异的物质，这使得它们对病理机制的贡献可能有所不同。将LX-2肝星状细胞（HSCs）暴露于由黄嘌呤和黄嘌呤氧化酶产生的超氧阴离子自由基（O2(·-)）中。为了排除HSCs的激活是由于源自O2(·-)的过氧化氢所致，还研究了用铜锌超氧化物歧化酶和Tempol进行的对照孵育。O2(·-)的流入激活了HSCs，α-平滑肌肌动蛋白的表达以及转化生长因子β1和胶原蛋白的分泌证明了这一点。我们进一步发现，用4,4'-二异硫氰酸根合芪-2,2'-二磺酸（DIDS）、5-硝基-2-(3-苯基丙基氨基)苯甲酸（NPPB）或茚满氧基乙酸（IAA-94）阻断氯离子通道可防止细胞内O2(·-)水平的升高以及HSCs的激活。这些发现表明，O2(·-)参与了肝纤维化的发展，并且O2(·-)通过氯离子通道进入星状细胞对其激活至关重要。这项研究为ROS诱导肝纤维化的机制提供了新的见解。此外，我们的数据表明氯离子通道构成了新型抗纤维化药物的潜在靶点。
