Key Laboratory for Biotechnology on Medicinal Plants of Jiangsu Province, School of Life Science, Xuzhou Normal University, No. 101, Shanghai Road, Tangshan New Area, Xuzhou City 221116, Jiangsu, PR China.
Environ Toxicol Pharmacol. 2010 Mar;29(2):158-66. doi: 10.1016/j.etap.2009.12.006. Epub 2010 Jan 7.
Quercetin, a flavonoid, effectively improved the lead-induced histology changes including structure damage and leukocyte infiltration in rat liver. The present study was designed to explore the protective mechanism of quercetin against lead-induced hepatic injury. We found that quercetin markedly decreased the MDA and H(2)O(2) levels and lowered the GSH/GSSG ratio in the liver of lead-treated rat. Moreover, quercetin markedly restored Cu/Zn-SOD, Mn-SOD, CAT and GPx activities and upregulated mRNA expression levels of these proteins in the liver of lead-treated rat. Western blot analysis showed that quercetin significantly inhibited apoptosis by modulating the ratio of Bax to Bcl-2 expression and suppressing the expression of phosphorylated JNK1/2 and cleaved caspase-3 in the liver of lead-treated rat. In conclusion, these data suggest that quercetin protects the rat liver from lead-induced injury by attenuating lipid peroxidation, renewing the activities of antioxidant enzymes and inhibiting apoptosis.
槲皮素是一种类黄酮，能有效改善铅诱导的大鼠肝脏组织学变化，包括结构损伤和白细胞浸润。本研究旨在探讨槲皮素对铅诱导肝损伤的保护机制。我们发现，槲皮素显著降低了铅处理大鼠肝脏中的 MDA 和 H(2)O(2)水平，并降低了 GSH/GSSG 比值。此外，槲皮素显著恢复了 Cu/Zn-SOD、Mn-SOD、CAT 和 GPx 活性，并上调了铅处理大鼠肝脏中这些蛋白的 mRNA 表达水平。Western blot 分析表明，槲皮素通过调节 Bax 与 Bcl-2 表达的比值，抑制磷酸化 JNK1/2 和裂解 caspase-3 的表达，显著抑制了铅处理大鼠肝脏中的细胞凋亡。总之，这些数据表明，槲皮素通过减轻脂质过氧化、恢复抗氧化酶活性和抑制细胞凋亡来保护大鼠肝脏免受铅诱导的损伤。
