Increased Oxidative Stress and Hypoxia Inducible Factor-1 Expression during Arteriovenous Fistula Maturation.
BACKGROUND
The poor clinical results that are frequently reported for arteriovenous fistulae (AVF) for hemodialysis are typically due to failure of AVF maturation. We hypothesized that early AVF maturation is associated with generation of reactive oxygen species and activation of the hypoxia-inducible factor-1 (HIF-1) pathway, potentially promoting neointimal hyperplasia. We tested this hypothesis using a previously reported mouse AVF model that recapitulates human AVF maturation.


METHODS
Aortocaval fistulae were created in C57Bl/6 mice and compared with sham-operated mice. AVFs or inferior vena cavas were analyzed using a microarray, Amplex Red for extracellular H2O2, quantitative polymerase chain reaction, immunohistochemistry, and immunoblotting for HIF-1α and immunofluorescence for NOX-2, nitrotyrosine, heme oxygenase-1 (HO-1), and vascular endothelial growth factor (VEGF)-A.


RESULTS
Oxidative stress was higher in AVF than that in control veins, with more H2O2(P = 0.007) and enhanced nitrotyrosine immunostaining (P = 0.005). Immunohistochemistry and immunoblot showed increased HIF-1α immunoreactivity in the AVF endothelium; HIF-1 targets NOX-2, HO-1 and VEGF-A were overexpressed in the AVF (P < 0.01). AVF expressed increased numbers of HIF-1α (P < 0.0001) and HO-1 (P < 0.0001) messenger RNA transcripts.


CONCLUSIONS
Oxidative stress increases in mouse AVF during early maturation, with increased expression of HIF-1α and its target genes NOX-2, HO-1, and VEGF-A. These results suggest that clinical strategies to improve AVF maturation could target the HIF-1 pathway.
Vascular Biology and Therapeutics Program, Yale University School of Medicine, New Haven, CT; Department of Vascular Surgery, University Hospital of Nice-Sophia Antipolis, Nice, France. Electronic address: sadaghianloo.n@chu-nice.fr.
Nirvana
N
Sadaghianloo
Vascular Biology and Therapeutics Program, Yale University School of Medicine, New Haven, CT; Department of Surgery, Yale University School of Medicine, New Haven, CT; Division of Vascular Surgery, Department of Surgery, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan.
Kota
K
Yamamoto
Vascular Biology and Therapeutics Program, Yale University School of Medicine, New Haven, CT; Department of Vascular Surgery, First Affiliated Hospital of Zhengzhou University, Henan, China.
Hualong
H
Bai
National Cancer Center Research Institute, Tokyo, Japan; Department of Pathology, Yale University School of Medicine, New Haven, CT.
Masayuki
M
Tsuneki
Vascular Biology and Therapeutics Program, Yale University School of Medicine, New Haven, CT; Department of Surgery, Yale University School of Medicine, New Haven, CT.
Clinton D
CD
Protack
Vascular Biology and Therapeutics Program, Yale University School of Medicine, New Haven, CT; Department of Surgery, Yale University School of Medicine, New Haven, CT.
Michael R
MR
Hall
Department of Vascular Surgery, University Hospital of Nice-Sophia Antipolis, Nice, France.
Serge
S
Declemy
Department of Vascular Surgery, University Hospital of Nice-Sophia Antipolis, Nice, France.
Réda
R
Hassen-Khodja
Department of Pathology, Yale University School of Medicine, New Haven, CT.
Joseph
J
Madri
Vascular Biology and Therapeutics Program, Yale University School of Medicine, New Haven, CT; Department of Surgery, Yale University School of Medicine, New Haven, CT; Veterans Affairs Connecticut Healthcare Systems, West Haven, CT.
Alan
A
Dardik
D000818:Animals; D001011:Aorta / Q000378:metabolism / Q000473:pathology / Q000503:physiopathology / Q000601:surgery*; D001166:Arteriovenous Shunt, Surgical / Q000009:adverse effects; D005786:Gene Expression Regulation; D051547:Heme Oxygenase-1 / Q000235:genetics / Q000378:metabolism; D006861:Hydrogen Peroxide / Q000378:metabolism; D006965:Hyperplasia; D051795:Hypoxia-Inducible Factor 1, alpha Subunit / Q000235:genetics / Q000378:metabolism*; D008297:Male; D008565:Membrane Proteins / Q000235:genetics / Q000378:metabolism; D008810:Mice, Inbred C57BL; D000074662:NADPH Oxidase 2 / Q000378:metabolism; D058426:Neointima; D018384:Oxidative Stress; D017382:Reactive Oxygen Species / Q000378:metabolism*; D015398:Signal Transduction; D013997:Time Factors; D014443:Tyrosine / Q000031:analogs & derivatives / Q000378:metabolism; D042461:Vascular Endothelial Growth Factor A / Q000235:genetics / Q000378:metabolism; D014654:Vascular Patency; D014682:Vena Cava, Inferior / Q000378:metabolism / Q000473:pathology / Q000503:physiopathology / Q000601:surgery*
C497443:Hif1a protein, mouse; D051795:Hypoxia-Inducible Factor 1, alpha Subunit; D008565:Membrane Proteins; D017382:Reactive Oxygen Species; D042461:Vascular Endothelial Growth Factor A; C467480:vascular endothelial growth factor A, mouse; C002744:3-nitrotyrosine; D014443:Tyrosine; D006861:Hydrogen Peroxide; D051547:Heme Oxygenase-1; C496542:Hmox1 protein, mouse; C488842:Cybb protein, mouse; D000074662:NADPH Oxidase 2