PDF(Pubmed)
Abstract：
Aristolochic acid I (AAI) is a well established nephrotoxin and human carcinogen. Cytosolic NAD(P)H quinone oxidoreductase 1 (NQO1) plays an important role in the nitro reduction of aristolochic acids, leading to production of aristoloactam and AA-DNA adduct. Application of a potent NQO1 inhibitor dicoumarol is limited by its life-threatening side effect as an anticoagulant and the subsequent hemorrhagic complications. As traditional medicines containing AAI remain available in the market, novel NQO1 inhibitors are urgently needed to attenuate the toxicity of AAI exposure. In this study, we employed comprehensive 2D NQO1 biochromatography to screen candidate compounds that could bind with NQO1 protein. Four compounds, i.e., skullcapflavone II (SFII), oroxylin A, wogonin and tectochrysin were screened out from Scutellaria baicalensis. Among them, SFII was the most promising NQO1 inhibitor with a binding affinity (KD = 4.198 μmol/L) and inhibitory activity (IC50 = 2.87 μmol/L). In human normal liver cell line (L02) and human renal proximal tubular epithelial cell line (HK-2), SFII significantly alleviated AAI-induced DNA damage and apoptosis. In adult mice, oral administration of SFII dose-dependently ameliorated AAI-induced renal fibrosis and dysfunction. In infant mice, oral administration of SFII suppressed AAI-induced hepatocellular carcinoma initiation. Moreover, administration of SFII did not affect the coagulation function in short term in adult mice. In conclusion, SFII has been identified as a novel NQO1 inhibitor that might impede the risk of AAI to kidney and liver without obvious side effect.
摘要：
马兜铃酸I（AAI）是一种公认的肾毒素和人类致癌物。胞质NAD（P）H醌氧化还原酶1（NQO1）在马兜铃酸的硝基还原中起重要作用，导致产生马斯特洛内酰胺和AA-DNA加合物。有效的NQO1抑制剂双香豆醇的应用受到其作为抗凝剂的危及生命的副作用和随后的出血性并发症的限制。由于含有AAI的传统药物在市场上仍然可用，迫切需要新型NQO1抑制剂来减轻AAI暴露的毒性。在这项研究中,我们采用了全面的2DNQO1生物色谱来筛选可以与NQO1蛋白结合的候选化合物。四种化合物,即，黄芩黄酮II(SFII),奥木精A,从黄芩中筛选出汉黄芩素和曲素。其中,SFII是最有前途的NQO1抑制剂，具有结合亲和力（KD=4.198μmol/L）和抑制活性（IC50=2.87μmol/L）。在人正常肝细胞系（L02）和人肾近端肾小管上皮细胞系（HK-2）中，SFII显著减轻AAI诱导的DNA损伤和细胞凋亡。在成年小鼠中，口服SFII剂量依赖性改善AAI诱导的肾纤维化和功能障碍。在幼鼠中，口服SFII抑制AAI诱导的肝细胞癌发生。此外，SFII的给药在短期内不会影响成年小鼠的凝血功能。总之,SFII已被确定为一种新型NQO1抑制剂，可能会阻止AAI对肾脏和肝脏的风险，而不会产生明显的副作用。
