Qiao Panshuang, Sun Yi, Wang Yiming, Lin Simei, An Yongpan, Wang Liang, Liu Jihan, Huang Yajun, Yang Baoxue, Zhou Hong
State Key Laboratory of Natural and Biomimetic Drugs, Department of Pharmacology, School of Basic Medical Sciences, Peking University, Beijing 100191, China.
Department of Pharmacology, School of Pharmacy, China Pharmaceutical University, Nanjing 210009, China.
Antioxidants (Basel). 2023 Apr 28;12(5):1022. doi: 10.3390/antiox12051022.
Hyperuricemia (HUA)-induced oxidative stress is a crucial contributor to hyperuricemic nephropathy (HN), but the molecular mechanisms underlying the disturbed redox homeostasis in kidneys remain elusive. Using RNA sequencing, together with biochemical analyses, we found that nuclear factor erythroid 2-related factor 2 (NRF2) expression and nuclear localization levels were increased in early HN progression and then gradually declined below the baseline level. We identified the impaired activity of the NRF2-activated antioxidant pathway as a driver of oxidative damage in HN progression. Through deletion, we further confirmed aggravated kidney damage in knockout HN mice compared with HN mice. In contrast, the pharmacological agonist of NRF2 improved kidney function and alleviated renal fibrosis in mice. Mechanistically, the activation of NRF2 signaling reduced oxidative stress by restoring mitochondrial homeostasis and reducing NADPH oxidase 4 (NOX4) expression in vivo or in vitro. Moreover, the activation of NRF2 promoted the expression levels of heme oxygenase 1 (HO-1) and quinone oxidoreductase 1 (NQO1) and enhanced the antioxidant capacity of cells. Furthermore, the activation of NRF2 ameliorated renal fibrosis in HN mice through the downregulation of the transforming growth factor-beta 1 (TGF-β1) signaling pathway and ultimately delayed the progression of HN. Collectively, these results suggested NRF2 as a key regulator in improving mitochondrial homeostasis and fibrosis in renal tubular cells by reducing oxidative stress, upregulating the antioxidant signaling pathway, and downregulating the TGF-β1 signaling pathway. The activation of NRF2 represents a promising strategy to restore redox homeostasis and combat HN.
高尿酸血症(HUA)诱导的氧化应激是高尿酸血症肾病(HN)的关键促成因素,但肾脏中氧化还原稳态紊乱的分子机制仍不清楚。通过RNA测序以及生化分析,我们发现核因子红细胞2相关因子2(NRF2)的表达和核定位水平在HN早期进展过程中升高,然后逐渐下降至基线水平以下。我们确定NRF2激活的抗氧化途径活性受损是HN进展中氧化损伤的驱动因素。通过基因敲除,我们进一步证实与HN小鼠相比,敲除NRF2的HN小鼠肾脏损伤加重。相反,NRF2的药理激动剂改善了小鼠的肾功能并减轻了肾纤维化。从机制上讲,NRF2信号的激活通过在体内或体外恢复线粒体稳态并降低NADPH氧化酶4(NOX4)的表达来降低氧化应激。此外,NRF2的激活促进了血红素加氧酶1(HO-1)和醌氧化还原酶1(NQO1)的表达水平,并增强了细胞的抗氧化能力。此外,NRF2的激活通过下调转化生长因子-β1(TGF-β1)信号通路改善了HN小鼠的肾纤维化,并最终延缓了HN的进展。总的来说,这些结果表明NRF2是通过降低氧化应激、上调抗氧化信号通路和下调TGF-β1信号通路来改善肾小管细胞线粒体稳态和纤维化的关键调节因子。NRF2的激活是恢复氧化还原稳态和对抗HN的一种有前景的策略。