1. Academic Validation
  2. Roles of AhR/CYP1s signaling pathway mediated ROS production in uremic cardiomyopathy

Roles of AhR/CYP1s signaling pathway mediated ROS production in uremic cardiomyopathy

  • Toxicol Lett. 2024 Apr 24:396:81-93. doi: 10.1016/j.toxlet.2024.04.005.
Wei Lu 1 Shi Cheng 1 Jiarui Xu 1 Zilong Xiao 2 Yong Yu 2 Qiwen Xie 3 Yi Fang 1 Ruizhen Chen 2 Bo Shen 4 Yeqing Xie 5 Xiaoqiang Ding 6
Affiliations

Affiliations

  • 1 Division of Nephrology, Zhongshan Hospital, Fudan University, Shanghai 200032, China; Shanghai Medical Center of Kidney Disease, China; Kidney and Dialysis Institute of Shanghai, China; Kidney and Blood Purification Key Laboratory of Shanghai, China.
  • 2 Division of Cardiology, Zhongshan Hospital, Fudan University, Shanghai 200032, China.
  • 3 Department of Nephrology, Xiamen Branch, Zhongshan hospital, Fudan University; Nephrology, China; Clinical Quality Control Center of Xiamen, No.668 Jinhu Road, Xiamen, Fujian 361006, China.
  • 4 Division of Nephrology, Zhongshan Hospital, Fudan University, Shanghai 200032, China; Shanghai Medical Center of Kidney Disease, China; Kidney and Dialysis Institute of Shanghai, China; Kidney and Blood Purification Key Laboratory of Shanghai, China. Electronic address: shen.bo@zs-hospital.sh.cn.
  • 5 Division of Nephrology, Zhongshan Hospital, Fudan University, Shanghai 200032, China; Shanghai Medical Center of Kidney Disease, China; Kidney and Dialysis Institute of Shanghai, China; Kidney and Blood Purification Key Laboratory of Shanghai, China. Electronic address: xie.yeqing@zs-hospital.sh.cn.
  • 6 Division of Nephrology, Zhongshan Hospital, Fudan University, Shanghai 200032, China; Shanghai Medical Center of Kidney Disease, China; Kidney and Dialysis Institute of Shanghai, China; Kidney and Blood Purification Key Laboratory of Shanghai, China. Electronic address: ding.xiaoqiang@zs-hospital.sh.cn.
Abstract

Purpose: Uremic cardiomyopathy (UCM) is the leading cause of chronic kidney disease (CKD) related mortality. Uremic toxins including indoxyl sulfate (IS) play important role during the progression of UCM. This study was to explore the underlying mechanism of IS related myocardial injury.

Methods: UCM rat model was established through five-sixths nephrectomy to evaluate its effects on blood pressure, cardiac impairment, and histological changes using echocardiography and histological analysis. Additionally, IS was administered to neonatal rat cardiomyocytes (NRCMs) and the human cardiomyocyte cell line AC16. DHE staining and peroxide-sensitive dye 2',7'-dichlorofluorescein diacetate (H2DCFDA) was conducted to assess the Reactive Oxygen Species (ROS) production. Cardiomyocyte hypertrophy was estimated using wheat germ agglutinin (WGA) staining and immunofluorescence. Aryl Hydrocarbon Receptor (AhR) translocation was observed by immunofluorescence. The activation of AhR was evaluated by immunoblotting of Cytochrome P450 1 s (CYP1s) and quantitative Real-Time PCR (RT-PCR) analysis of AHRR and PTGS2. Additionally, the pro-oxidative and pro-hypertrophic effects were evaluated using the AhR inhibitor CH-223191, the CYP1s inhibitor Alizarin and the ROS scavenger N-Acetylcysteine (NAC).

Results: UCM rat model was successfully established, and cardiac hypertrophy, accompanied by increased blood pressure, and myocardial fibrosis. Further research confirmed the activation of the AhR pathway in UCM rats including AhR translocation and downstream protein CYP1s expression, accompanied with increasing ROS production detected by DHE staining. In vitro experiment demonstrated a translocation of AhR triggered by IS, leading to significant increase of downstream gene expression. Subsequently study indicated a close relationship between the production of ROS and the activation of AhR/CYP1s, which was effectively blocked by applying AhR inhibitor, CYP1s inhibitor and siRNA against AhR. Moreover, the inhibition of AhR/CYP1s/ROS pathway collectively blocked the pro-hypertrophic effect of IS-mediated cardiomyopathy.

Conclusion: This study provides evidence that the AhR/CYP1s pathway is activated in UCM rats, and this activation is correlated with the uremic toxin IS. In vitro studies indicate that IS can stimulate the AhR translocation in cardiomyocyte, triggering to the production of intracellular ROS via CYP1s. This process leads to prolonged oxidative stress stimulation and thus contributes to the progression of uremic toxin-mediated cardiomyopathy.

Keywords

Aryl hydrocarbon receptor; Cytochrome P450s; End-stage renal disease; Indoxyl sulfate; Uremic cardiomyopathy.

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