Deleterious vascular effects of indoxyl sulfate and reversal by oral adsorbent AST-120. Issue 1 (November 2015)

• Record Type: Journal Article
• Authors: Six, Isabelle; Gross, Priscilla; Rémond, Mathieu C.; Chillon, Jean Marc; Poirot, Sabrina; Drueke, Tilman B.; Massy, Ziad A.
• Is Part Of: Atherosclerosis. Volume 243:Issue 1(2015)
• Page Start: 248
• Page End: 256
• Publication Date: 2015-11
• Subjects: Indoxyl sulfate -- Endothelial dysfunction -- CKD -- Mouse -- AST-120; Arteriosclerosis -- Periodicals; Electronic journals; 616.136
• DOI: 10.1016/j.atherosclerosis.2015.09.019
• Languages: English
• ISSNs: 0021-9150

Abstract

Abstract: Background: In chronic kidney disease (CKD), blood vessels are permanently exposed to uremic toxins such as indoxyl sulfate (IS). We hypothesized that IS could alter vascular tone and that reducing its serum concentration could be beneficial. Design: We studied acute and longer-term effects of IS and AST-120, an oral charcoal adsorbent, on vascular reactivity, endothelium integrity and expression of adhesion molecules VCAM-1 and ICAM-1 in aortic rings of normal and uremic wild type (WT) mice in vitro, and the cardiovascular effects of AST-120 in both WT and apoE−/− mice with CKD in vivo . Results: In vitro, 1.0 mM IS acutely reduced vascular relaxation (64% for IS 1.0 mM vs. 80% for control, p < 0.05). The effect was more marked after 4 days exposure (39% for IS 1.0 mM 4 days; p < 0.001, prolonged vs. acute exposure), and was associated with endothelial cell loss and upregulation of ICAM-1/VCAM-1 expression. In vitro, AST-120 restored normal vascular function and prevented IS induced endothelial cell loss and ICAM-1/VCAM-1 upregulation. In vivo, AST-120 treatment of CKD mice (1) improved vascular relaxation (72% vs. 48% maximal relaxation in treated vs. untreated mice, p < 0.001), (2) reduced aortic VCAM-1 and ICAM-1 expression, (3) decreased aorta systolic expansion rate (9 ± 3% CKD vs. 14 ± 3% CKD + AST-120, p < 0.02), and (4) prevented the increase in pulse wave velocity (3.56 ± 0.17 m/s CKD vs. 3.10 ± 0.08 m/s CKD + AST-120, p < 0.006). Similar changes were observed in apoE−/− mice. Conclusion: IS appears to be an important contributor to the vascular dysfunction associated with CKD. AST-120 treatment ameliorates this dysfunction, possibly via a decrease in serum IS concentration. Highlights: Indoxyl sulfate reduces vascular relaxation and induces endothelial cell loss. AST-120 treatment improves cardiovascular dysfunction associated with CKD. Indoxyl sulfate plays a role in cardiovascular dysfunction associated with CKD. The cardiovascular dysfunction associated with CKD is overcome by AST-120 treatment.