101. Characterization of cytotoxic effects of aristolochic acids on the vascular endothelium
- Author
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Estelle N. H. Youl, Salma El Mere, Marie-Hélène Antoine, Stéphanie Pochet, Cécile Husson, Charaf El Khattabi, Anne-Emilie Decleves, and Joëlle Nortier
- Subjects
0301 basic medicine ,Male ,medicine.medical_specialty ,Endothelial cells ,Aristolochic acid ,chemistry.chemical_element ,Aorta, Thoracic ,Aortic ring ,Calcium ,AMP-Activated Protein Kinases ,Toxicology ,Calcium in biology ,Cell Line ,Superoxide dismutase ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Internal medicine ,medicine ,Animals ,Humans ,Viability assay ,Rats, Wistar ,Intracellular calcium ,Calcium metabolism ,biology ,Chemistry ,Superoxide Dismutase ,AMPK ,Endothelial Cells ,General Medicine ,Sciences bio-médicales et agricoles ,Endothelial stem cell ,030104 developmental biology ,Endocrinology ,Oxidative stress ,030220 oncology & carcinogenesis ,biology.protein ,Aristolochic Acids ,Endothelium, Vascular ,Reactive Oxygen Species - Abstract
Aristolochic acid nephropathy (AAN) is characterized by interstitial fibrosis, proximal tubular atrophy, and hypoxia. A correlation between a reduced peritubular capillary density and the severity of fibrosis has been demonstrated. As calcium, redox and energetic homeostasis are crucial in maintaining endothelial cell function and survival, we aimed to investigate AA-induced disturbances involved in endothelial cell injury. Our results showed a cytotoxic effect of AA on EAhy926 endothelial cells. Exposure of aortic rings to AA impaired vascular relaxation to Acetylcholine (ACh). Increased levels of intracellular reactive oxygen species (ROS) were observed in cells exposed to AA. Pre-treatment with antioxidant N-acetyl cysteine inhibited AA-induced cell death. Superoxide dismutase resulted in restoring ACh-induced relaxation. An increase in intracellular calcium level ([Ca2+]i) was observed on endothelial cells. Calcium chelators BAPTA-AM or APB, a specific inhibitor of IP3R, improved cell viability. Moreover, AA exposure led to reduced AMP-activated protein kinase (AMPK) expression. AICAR, an activator of AMPK, improved the viability of AA-intoxicated cells and inhibited the rise of cytosolic [Ca2+]i levels. This study provides evidence that AA exposure increases ROS generation, disrupts calcium homeostasis and decreases AMPK activity. It also suggests that significant damage observed in endothelial cells may enhance microcirculation defects, worsening hypoxia and tubulointerstitial lesions., info:eu-repo/semantics/published
- Published
- 2019