Simone S, Rascio F, Castellano G, Divella C, Chieti A, Ditonno P, Battaglia M, Crovace A, Staffieri F, Oortwijn B, Stallone G, Gesualdo L, Pertosa G, Grandaliano G
Nephrology, Dialysis, and Transplantation Unit, Department of Emergency and Organ Transplantation, University of Bari "Aldo Moro," 70121 Bari, Italy.
Nephrology, Dialysis, and Transplantation Unit, Department of Medical and Surgical Sciences, University of Foggia, 71100 Foggia, Italy.
Free Radic Biol Med. 2014 Sep;74:263-73. doi: 10.1016/j.freeradbiomed.2014.07.003. Epub 2014 Jul 10.
NADPH oxidase plays a central role in mediating oxidative stress during heart, liver, and lung ischemia/reperfusion injury, but limited information is available about NADPH oxidase in renal ischemia/reperfusion injury. Our aim was to investigate the activation of NADPH oxidase in a swine model of renal ischemia/reperfusion damage. We induced renal ischemia/reperfusion in 10 pigs, treating 5 of them with human recombinant C1 inhibitor, and we collected kidney biopsies before ischemia and 15, 30, and 60 min after reperfusion. Ischemia/reperfusion induced a significant increase in NADPH oxidase 4 (NOX-4) expression at the tubular level, an upregulation of NOX-2 expression in infiltrating monocytes and myeloid dendritic cells, and 8-oxo-7,8-dihydro-2'-deoxyguanosine synthesis along with a marked upregulation of NADPH-dependent superoxide generation. This burden of oxidative stress was associated with an increase in tubular and interstitial expression of the myofibroblast marker α-smooth muscle actin (α-SMA). Interestingly, NOX-4 and NOX-2 expression and the overall NADPH oxidase activity as well as α-SMA expression and 8-oxo-7,8-dihydro-2'-deoxyguanosine synthesis were strongly reduced in C1-inhibitor-treated animals. In vitro, when we incubated tubular cells with the anaphylotoxin C3a, we observed an enhanced NADPH oxidase activity and α-SMA protein expression, which were both abolished by NOX-4 silencing. In conclusion, our findings suggest that NADPH oxidase is activated during ischemia/reperfusion in a complement-dependent manner and may play a potential role in the pathogenesis of progressive renal damage in this setting.
NADPH氧化酶在介导心脏、肝脏和肺缺血/再灌注损伤期间的氧化应激中起核心作用，但关于NADPH氧化酶在肾脏缺血/再灌注损伤中的信息有限。我们的目的是研究猪肾脏缺血/再灌注损伤模型中NADPH氧化酶的激活情况。我们对10头猪诱导肾脏缺血/再灌注，其中5头用重组人C1抑制剂治疗，在缺血前以及再灌注后15、30和60分钟采集肾脏活检组织。缺血/再灌注导致肾小管水平的NADPH氧化酶4（NOX-4）表达显著增加，浸润单核细胞和髓样树突状细胞中NOX-2表达上调，以及8-氧代-7,8-二氢-2'-脱氧鸟苷合成，同时NADPH依赖性超氧化物生成显著上调。这种氧化应激负担与成肌纤维细胞标志物α-平滑肌肌动蛋白（α-SMA）的肾小管和间质表达增加有关。有趣的是，在C1抑制剂治疗的动物中，NOX-4和NOX-2表达以及总体NADPH氧化酶活性以及α-SMA表达和8-氧代-7,8-二氢-2'-脱氧鸟苷合成均显著降低。在体外，当我们用过敏毒素C3a孵育肾小管细胞时，我们观察到NADPH氧化酶活性和α-SMA蛋白表达增强，而这两者都被NOX-4沉默所消除。总之，我们的研究结果表明，NADPH氧化酶在缺血/再灌注期间以补体依赖性方式被激活，并可能在这种情况下进行性肾损伤的发病机制中发挥潜在作用。
