Differential Effects of Indoxyl Sulfate and Inorganic Phosphate in a Murine Cerebral Endothelial Cell Line (bEnd.3)

Toxins

Andrບ E. M. Stinghen¹  Jean-Marc Chillon¹  Ziad A. Massy¹ 

[1] Inserm U1088, Department of Pharmacy, 1 rue des Louvels, Amiens F-80037 Cédex 1, France; E-Mails:

关键词: chronic kidney disease;    uremic toxins;    endothelial dysfunction;    nitric oxide;    reactive oxygen species;   

DOI  :  10.3390/toxins6061742

来源: mdpi

【 摘 要 】

Endothelial dysfunction plays a key role in stroke in chronic kidney disease patients. To explore the underlying mechanisms, we evaluated the effects of two uremic toxins on cerebral endothelium function. bEnd.3 cells were exposed to indoxyl sulfate (IS) and inorganic phosphate (Pi). Nitric oxide (NO), reactive oxygen species (ROS) and O₂•^– were measured using specific fluorophores. Peroxynitrite and eNOS uncoupling were evaluated using ebselen, a peroxide scavenger, and tetrahydrobiopterin (BH₄), respectively. Cell viability decreased after IS or Pi treatment (p < 0.01). Both toxins reduced NO production (IS, p < 0.05; Pi, p < 0.001) and induced ROS production (p < 0.001). IS and 2 mM Pi reduced O₂•^– production (p < 0.001). Antioxidant pretreatment reduced ROS levels in both IS- and Pi-treated cells, but a more marked reduction of O₂•^– production was observed in Pi-treated cells (p < 0.001). Ebselen reduced the ROS production induced by the two toxins (p < 0.001); suggesting a role of peroxynitrite in this process. BH₄ addition significantly reduced O₂•^– and increased NO production in Pi-treated cells (p < 0.001), suggesting eNOS uncoupling, but had no effect in IS-treated cells. This study shows, for the first time, that IS and Pi induce cerebral endothelial dysfunction by decreasing NO levels due to enhanced oxidative stress. However, Pi appears to be more deleterious, as it also induces eNOS uncoupling.

【 授权许可】

CC BY   
© 2014 by the authors; licensee MDPI, Basel, Switzerland.