Motterlini R, Foresti R, Intaglietta M, Winslow R M
Department of Bioengineering, University of California at San Diego, La Jolla 92093, USA.
Am J Physiol. 1996 Jan;270(1 Pt 2):H107-14. doi: 10.1152/ajpheart.1996.270.1.H107.
We investigated the effect of nitric oxide (NO) on the induction of the stress protein heme oxygenase and its protective role in vascular endothelial cells exposed to hydrogen peroxide. Treatment of porcine aortic endothelial cells for 6 h with the NO-releasing compounds (0.1-1 mM) sodium nitroprusside (SNP), S-nitroso-N-acetylpenicillamine (SNAP), and 3-morpholinosydnonimine (SIN-1) resulted in a concentration-dependent increase in heme oxygenase activity. At 1 mM, the activity of heme oxygenase was augmented 8.5-fold with SNP, 5.8-fold with SNAP, and 5.7-fold with SIN-1 over the control value. In contrast, endothelial cells exposed to 100 microM S-bromoguanosine 3',5'-cyclic monophosphate, a tissue-permeable analogue that mimics the action of guanosine 3',5'-cyclic monophosphate, did not show any change in heme oxygenase activity. Activation of the inducible NO synthase by the synergistic action of bacterial lipopolysaccharide (250 ng/ml) and interferon-gamma (100 U/ml) also increased endothelial heme oxygenase activity by 3.2-fold (P < 0.05 vs control). Methylene blue (1 microM), an inhibitor of both NO synthase and guanylate cyclase activities, completely abolished this effect. Cells previously exposed to SNAP and SIN-1 exhibited a significant protection against the cytotoxicity mediated by hydrogen peroxide (250 microM) (P < 0.05). Conversely, SNP did not show any protective effects, possibly because of catalytic iron released during its chemical decomposition. In fact, the iron chelator deferoxamine (5 mM) completely suppressed the SNP-mediated cytotoxicity and partially attenuated the activity of heme oxygenase to a level equal to that mediated by SIN-1 and SNAP. These results indicate that NO is a determinant in the modulation of the activity of heme oxygenase leading to a major resistance of the endothelium to oxidative stress.
我们研究了一氧化氮（NO）对应激蛋白血红素加氧酶诱导的影响及其在暴露于过氧化氢的血管内皮细胞中的保护作用。用释放NO的化合物（0.1 - 1 mM）硝普钠（SNP）、S - 亚硝基 - N - 乙酰青霉胺（SNAP）和3 - 吗啉代 sydnonimine（SIN - 1）处理猪主动脉内皮细胞6小时，导致血红素加氧酶活性呈浓度依赖性增加。在1 mM时，与对照值相比，SNP使血红素加氧酶活性增强8.5倍，SNAP增强5.8倍，SIN - 1增强5.7倍。相比之下，暴露于100 microM S - 溴鸟苷3'，5' - 环磷酸，一种模拟鸟苷3'，5' - 环磷酸作用的组织可渗透类似物的内皮细胞，血红素加氧酶活性未显示任何变化。细菌脂多糖（250 ng/ml）和干扰素 - γ（100 U/ml）的协同作用激活诱导型NO合酶，也使内皮血红素加氧酶活性增加3.2倍（与对照相比，P < 0.05）。一氧化氮合酶和鸟苷酸环化酶活性的抑制剂亚甲蓝（1 microM）完全消除了这种作用。先前暴露于SNAP和SIN - 1的细胞对过氧化氢（250 microM）介导的细胞毒性表现出显著的保护作用（P < 0.05）。相反，SNP未显示任何保护作用，可能是因为其化学分解过程中释放的催化铁。事实上，铁螯合剂去铁胺（5 mM）完全抑制了SNP介导的细胞毒性，并部分减弱了血红素加氧酶的活性，使其达到与SIN - 1和SNAP介导的水平相当。这些结果表明，NO是调节血红素加氧酶活性的决定因素，导致内皮细胞对氧化应激产生主要抗性。
