Inhibition of the Na+/H+ exchanger reduces rat hepatic stellate cell activity and liver fibrosis:: An in vitro and in vivo study
Inhibition of the Na+/H+ exchanger reduces rat hepatic stellate cell activity and liver fibrosis:: An in vitro and in vivo study
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DOI：
10.1053/gast.2001.21203
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发表时间：
2001-02-01
期刊：
影响因子：
29.4
通讯作者：
Svegliati-Baroni, G
中科院分区：
文献类型：
--
作者：
Benedetti, A;Di Sario, A;Svegliati-Baroni, G
背景与目的：Na+/H+交换器是肝星状细胞（HSC）中主要的细胞内pH（pH(i)）调节剂，在调节增殖和基因表达中发挥关键作用。我们在体内和体外评估了这种交换剂的特异性抑制对 HSC 增殖和胶原蛋白合成的影响。方法：在血小板衍生生长因子 (PDGF)、转化生长因子 (TGF)-β1 抗坏血酸铁 (FeAsc) 和次氮基三乙酸铁溶液 (FeNTA) 存在下，在有或没有 Na+/H+ 交换抑制剂 5-N-乙基-N-异丙基阿米洛利 (EIPA) 的情况下，培养大鼠 HSC。 pH(i) 和 Na+/H+ 交换活性、细胞增殖和 I 型胶原积累分别通过使用荧光染料 2',7'-双-(羧乙基)-5(6)-羧基荧光素、溴脱氧尿苷免疫组织化学和酶联免疫吸附测定来测量。通过在用阿米洛利处理或未处理的大桶中给予二甲基亚硝胺和胆管结扎（BDL）来诱导体内肝纤维化。结果：PDGF、FeAsc 和 FeNTA 增加 Na+/H+ 交换活性并诱导 HSC 增殖。 TGF-β1 对 Na+/H+ 交换器没有影响，并且能够像 FeAsc 和 FeNTA 一样诱导 I 型胶原蛋白积累。 EIPA 抑制 PDGF、FeAsc 和 FeNTA 确定的所有作用，并且对 TGF-β1 诱导的胶原蛋白积累没有影响。在体内，阿米洛利减少 HSC 增殖、活化、胶原蛋白沉积和胶原蛋白合成。结论：Na+/H+交换体在肝纤维化的发生和体内HSC活化中发挥关键作用。
Background & Aims: The Na+/H+ exchanger is the main intracellular pH (pH(i)) regulator in hepatic stellate cells (HSCs) and plays a key role in regulating proliferation and gene expression. We evaluated the effect of specific inhibition of this exchanger on HSC proliferation and collagen synthesis in vivo and in vitro. Methods: Rat HSCs were incubated in the presence of platelet-derived growth factor (PDGF), transforming growth factor (TGF)-beta1 iron ascorbate (FeAsc), and ferric nitrilotriacetate solution (FeNTA) with or without the Na+/H+ exchanger inhibitor 5-N-ethyl-N-isopropyl-amiloride (EIPA). pH(i) and Na+/H+ exchanger activity, cell proliferation, and type I collagen accumulation were measured by using the fluorescent dye 2',7'-bis-(carboxyethyl)-5(6)-carboxyfluorescein, by immunohistochemistry for bromodeoxyuridine, and by enzyme-linked immunosorbent assay, respectively. In vivo liver fibrosis was induced by dimethylnitrosamine administration and bile duct ligation (BDL) in vats treated or not treated with amiloride. Results: PDGF, FeAsc, and FeNTA increased Na+/H+ exchange activity and induced HSC proliferation. TGF-beta1 had no effect on the Na+/H+ exchanger and was able, as for FeAsc and FeNTA, to induce type I collagen accumulation. EIPA inhibited all the effects determined by PDGF, FeAsc, and FeNTA and had no effect on TGF-beta1-induced collagen accumulation. In vivo, amiloride reduced HSC proliferation, activation, collagen deposition, and collagen synthesis. Conclusions: The Na+/H+ exchanger can play a key role in the development of liver fibrosis and in HSC activation in vivo.