Angiogenesis

, Volume 16, Issue 3, pp 609–624

In acute kidney injury, indoxyl sulfate impairs human endothelial progenitor cells: modulation by statin

  • Vin-Cent Wu
  • Guang-Huar Young
  • Po-Hsun Huang
  • Shyh-Chyi Lo
  • Kuo-Chuan Wang
  • Chiao-Yin Sun
  • Chan-Jung Liang
  • Tao-Ming Huang
  • Jou-Han Chen
  • Fan-Chi Chang
  • Yuh-Lien Chen
  • Yih-Shing Kuo
  • Jin-Bor Chen
  • Jaw-Wen Chen
  • Yung-Ming Chen
  • Wen-Jo Ko
  • Kwan-Dun Wu
  • The NSARF group
Original Paper

DOI: 10.1007/s10456-013-9339-8

Cite this article as:
Wu, V., Young, G., Huang, P. et al. Angiogenesis (2013) 16: 609. doi:10.1007/s10456-013-9339-8

Abstract

Renal ischemia rapidly mobilizes endothelial progenitor cells (EPCs), which provides renoprotection in acute kidney injury (AKI). Indoxyl sulfate (IS) is a protein-binding uremic toxin with a potential role in endothelial injury. In this study, we examined the effects and mechanisms of action of IS on EPCs in AKI. Forty-one consecutive patients (26 male; age, 70.1 ± 14.1 years) diagnosed with AKI according to the AKIN criteria were enrolled. The AKI patients had higher serum IS levels than patients with normal kidney function (1.35 ± 0.94 × 10−4M vs. 0.02 ± 0.02 × 10−4M, P < 0.01). IS levels were negatively correlated to the number of double-labeled (CD34+KDR+) circulating EPCs (P < 0.001). After IS stimulation, the cells displayed decreased expression of phosphorylated endothelial nitric oxide (NO) synthase, vascular cell adhesion molecule-1, increased reactive oxygen species, decreased proliferative capacity, increased senescence and autophagy, as well as decreased migration and angiogenesis. These effects of IS on EPCs were reversed by atorvastatin. Further, exogenous administration of IS significantly reduced EPC number in Tie2-GFP transgenic mice and attenuated NO signaling in aortic and kidney arteriolar endothelium after kidney ischemia–reperfusion injury in mice, and these effects were restored by atorvastatin. Our results are the first to demonstrate that circulating IS is elevated in AKI and has direct effects on EPCs via NO-dependent mechanisms both in vitro and in vivo. Targeting the IS-mediated pathways by NO-releasing statins such as atorvastatin may preempt disordered vascular wall pathology, and represent a novel EPC-rescued approach to impaired neovascularization after AKI.

Keywords

Indoxyl sulfateStatinEndothelial nitric oxide synthaseEndothelial progenitor cellsAutophagy

Abbreviations

AKI

Acute kidney injury

APO

Apocynin

ATO

Atorvastatin

CKD

Chronic kidney disease

CASP3

Activated caspase 3

Ctrl

Control

DAPI

DNA fluorochrome 4′-6-diamidine-2-phenyl indole

DCFDA

Dichlorofluorescin diacetate

eNOs

Endothelial nitric oxide synthase

EPC

Endothelial progenitor cells

ESRD

End stage renal disease

FITC

Fluorescein isothiocyanate

GAM

Generalized additive model

ICAM-1

Intercellular adhesion molecule 1

IS

Indoxyl sulfate

LC3

Light Chain 3

MTT

3-(4,5-cimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide

NAC

N-acetylcsyteine

NO

Nitric oxide

NOx

Reactive nitrogen species

NSARF

National Taiwan University Hospital Study Group on Acute Renal Failure

OAT

Organic anion transporter

ROS

Reactive oxygen species

SNP

Sodium nitroprusside

Prob

Probenecid

TNF

Transforming growth factor

TUNEL

Terminal deoxyribonucleotidyl transferase (TDT)-mediated dUTP-digoxigenin nick end labeling

VCAM

Vascular cell adhesion molecule

VWF

Von Willebrand factor

Supplementary material

10456_2013_9339_MOESM1_ESM.docx (2.7 mb)
Supplementary material 1 (DOCX 2727 kb)

Copyright information

© Springer Science+Business Media Dordrecht 2013

Authors and Affiliations

  • Vin-Cent Wu
    • 1
  • Guang-Huar Young
    • 2
  • Po-Hsun Huang
    • 3
  • Shyh-Chyi Lo
    • 4
  • Kuo-Chuan Wang
    • 5
  • Chiao-Yin Sun
    • 6
  • Chan-Jung Liang
    • 7
  • Tao-Ming Huang
    • 8
  • Jou-Han Chen
    • 1
  • Fan-Chi Chang
    • 9
  • Yuh-Lien Chen
    • 7
  • Yih-Shing Kuo
    • 10
  • Jin-Bor Chen
    • 11
  • Jaw-Wen Chen
    • 3
  • Yung-Ming Chen
    • 1
  • Wen-Jo Ko
    • 2
  • Kwan-Dun Wu
    • 1
  • The NSARF group
  1. 1.Department of Internal MedicineNational Taiwan University HospitalTaipeiTaiwan
  2. 2.Department of SurgeryNational Taiwan University HospitalTaipeiTaiwan
  3. 3.Division of Cardiology, Department of Internal MedicineTaipei Veterans General HospitalTaipeiTaiwan
  4. 4.Department of Laboratory MedicineNational Taiwan University HospitalTaipeiTaiwan
  5. 5.Department of NeurologyNational Taiwan University HospitalTaipeiTaiwan
  6. 6.Division of NephrologyChang Gung Memorial HospitalKeelungTaiwan
  7. 7.Department of Anatomy and Cell Biology, College of MedicineNational Taiwan University HospitalTaipeiTaiwan
  8. 8.Yun-Lin BranchNational Taiwan University HospitalTaipeiTaiwan
  9. 9.Chu-Tung BranchNational Taiwan University HospitalTaipeiTaiwan
  10. 10.Bei-Hu branchNational Taiwan University HospitalTaipeiTaiwan
  11. 11.Division of NephrologyChang Gung Memorial HospitalKaohsiungTaiwan