Binda D, Nicod L, Viollon-Abadie C, Rodriguez S, Berthelot A, Coassolo P, Richert L
Laboratoire de Biologie Cellulaire, UFR Médecine-Pharmacie, Besançon, France.
Mol Cell Biochem. 2001 Feb;218(1-2):139-46. doi: 10.1023/a:1007268825721.
We assessed the hepatic antioxidant status of spontaneously (SHR) and desoxicorticosterone acetate (DOCA)-induced hypertensive rats and that of respective normotensive Wistar Kyoto (WKY) and Sprague-Dawley (SPRD) rats. For this we evaluated, ex vivo in liver cytosols, reduced glutathione (GSH) content, glutathione-related enzyme (peroxidase, reductase and transferase) activities as well as the rate of lipid peroxidation in 9-11 week-old rats. The antioxidant status and the cytotoxicity of acetaminophen, a radical- and hydrogen peroxide-mediated hepatotoxic compound, were also assessed in vitro in cultured hepatocytes isolated from hypertensive (SHR, DOCA) and normotensive control (WKY, SPRD) rats. Our results suggest that a difference exists in the hepatic antioxidant status between rat strains, with GSH levels being lower (-15%) and lipid peroxidation rate higher (+30%) in WKY compared to SPRD rats. In hepatocyte cultures from WKY rats, both GSH content and catalase activity were lower (-30 and -70% respectively) compared to hepatocyte cultures from SPRD rats. This was associated with a 35% higher cytotoxicity of acetaminophen in cultured hepatocytes from WKY rats compared to that in hepatocytes from SPRD rats. Hypertension in DOCA rats (mmHg: 221+/-9 vs. 138+/-5 in control SPRD rats) was associated with decreases (about 30%) in both glutathione peroxidase (GSH-Px) and catalase activities, ex vivo in livers and in vitro in hepatocyte cultures. Hypertension in SHR (mmHg: 189+/-7 vs. 130+/-5 in control WKY rats) was also associated with decreases (about 50%) in GSH-Px activity, ex vivo in livers and in vitro in hepatocyte cultures but catalase activity was not modified. The IC50 of acetaminophen was also lower in hepatocytes from hypertensive rats compared to respective controls, which could be related to the weakened antioxidant status in hepatocytes from hypertensive rats. Our data thus suggest that hepatocyte cultures are appropriated tools in which to assess hepatotoxicity and hepatoprotection in hypertension.
我们评估了自发性高血压大鼠（SHR）和醋酸去氧皮质酮（DOCA）诱导的高血压大鼠以及各自的正常血压Wistar Kyoto（WKY）和Sprague-Dawley（SPRD）大鼠的肝脏抗氧化状态。为此，我们在9至11周龄大鼠的肝脏胞质溶胶中进行了体外评估，检测了还原型谷胱甘肽（GSH）含量、谷胱甘肽相关酶（过氧化物酶、还原酶和转移酶）活性以及脂质过氧化速率。还在从高血压（SHR、DOCA）和正常血压对照（WKY、SPRD）大鼠分离的培养肝细胞中进行了体外评估，检测了对乙酰氨基酚（一种由自由基和过氧化氢介导的肝毒性化合物）的抗氧化状态和细胞毒性。我们的结果表明，大鼠品系之间肝脏抗氧化状态存在差异，与SPRD大鼠相比，WKY大鼠的GSH水平较低（-15%），脂质过氧化速率较高（+30%）。在WKY大鼠的肝细胞培养物中，与SPRD大鼠的肝细胞培养物相比，GSH含量和过氧化氢酶活性均较低（分别降低-30%和-70%）。这与WKY大鼠培养肝细胞中对乙酰氨基酚的细胞毒性比SPRD大鼠肝细胞高35%有关。DOCA大鼠的高血压（血压：221±9 mmHg，而对照SPRD大鼠为138±5 mmHg）与肝脏离体和肝细胞培养物体外谷胱甘肽过氧化物酶（GSH-Px）和过氧化氢酶活性均降低（约30%）有关。SHR的高血压（血压：189±7 mmHg，而对照WKY大鼠为130±5 mmHg）也与肝脏离体和肝细胞培养物体外GSH-Px活性降低（约50%）有关，但过氧化氢酶活性未改变。与各自的对照相比，高血压大鼠肝细胞中对乙酰氨基酚的半数抑制浓度（IC50）也较低，这可能与高血压大鼠肝细胞中抗氧化状态减弱有关。因此，我们的数据表明，肝细胞培养物是评估高血压中肝毒性和肝保护作用的合适工具。
