Aminzadeh Mohammad A, Reisman Scott A, Vaziri Nosratola D, Shelkovnikov Stan, Farzaneh Seyed H, Khazaeli Mahyar, Meyer Colin J
Division of Nephrology and Hypertension, Schools of Medicine and Biological Science, University of California-Irvine, 101 The City Drive, City Tower, Suite 400, Orange, CA 92868, USA.
Reata Pharmaceuticals, Inc., 2801 Gateway Dr. Ste 150, Irving, TX 75063, USA.
Redox Biol. 2013 Oct 31;1(1):527-31. doi: 10.1016/j.redox.2013.10.007. eCollection 2013.
Chronic kidney disease (CKD) is associated with endothelial dysfunction and accelerated cardiovascular disease, which are largely driven by systemic oxidative stress and inflammation. Oxidative stress and inflammation in CKD are associated with and, in part, due to impaired activity of the cytoprotective transcription factor Nrf2. RTA dh404 is a synthetic oleanane triterpenoid compound which potently activates Nrf2 and inhibits the pro-inflammatory transcription factor NF-κB. This study was designed to test the effects of RTA dh404 on endothelial function, inflammation, and the Nrf2-mediated antioxidative system in the aorta of rats with CKD induced by 5/6 nephrectomy. Sham-operated rats served as controls. Subgroups of CKD rats were treated orally with RTA dh404 (2 mg/kg/day) or vehicle for 12 weeks. The aortic rings from untreated CKD rats exhibited a significant reduction in the acetylcholine-induced relaxation response which was restored by RTA dh404 administration. Impaired endothelial function in the untreated CKD rats was accompanied by significant reduction of Nrf2 activity (nuclear translocation) and expression of its cytoprotective target genes, as well as accumulation of nitrotyrosine and upregulation of NAD(P)H oxidases, 12-lipoxygenase, MCP-1, and angiotensin II receptors in the aorta. These abnormalities were ameliorated by RTA dh404 administration, as demonstrated by the full or partial restoration of the expression of all the above analytes to sham control levels. Collectively, the data demonstrate that endothelial dysfunction in rats with CKD induced by 5/6 nephrectomy is associated with impaired Nrf2 activity in arterial tissue, which can be reversed with long term administration of RTA dh404.
慢性肾脏病(CKD)与内皮功能障碍和心血管疾病加速相关,这在很大程度上是由全身氧化应激和炎症驱动的。CKD中的氧化应激和炎症与细胞保护性转录因子Nrf2活性受损相关,且部分归因于此。RTA dh404是一种合成的齐墩果烷三萜类化合物,可有效激活Nrf2并抑制促炎转录因子NF-κB。本研究旨在测试RTA dh404对5/6肾切除诱导的CKD大鼠主动脉内皮功能、炎症和Nrf2介导的抗氧化系统的影响。假手术大鼠作为对照。CKD大鼠亚组口服RTA dh404(2mg/kg/天)或赋形剂,持续12周。未经治疗的CKD大鼠的主动脉环对乙酰胆碱诱导的舒张反应显著降低,而给予RTA dh404后恢复。未经治疗的CKD大鼠内皮功能受损,同时Nrf2活性(核转位)及其细胞保护靶基因的表达显著降低,主动脉中硝基酪氨酸积累以及NAD(P)H氧化酶、12-脂氧合酶、单核细胞趋化蛋白-1和血管紧张素II受体上调。给予RTA dh404后,这些异常得到改善,上述所有分析物的表达全部或部分恢复到假手术对照水平即可证明。总体而言,数据表明,5/6肾切除诱导的CKD大鼠的内皮功能障碍与动脉组织中Nrf2活性受损相关,长期给予RTA dh404可逆转这一情况。