Abstract

BACKGROUND: Arteriovenous fistula (AVF) stenosis is the major cause of vascular access failure in hemodialysis. Adventitial remodeling has been suggested to play a role in the pathogenesis of AVF stenosis. This study aimed to evaluate adventitial fibrosis in stenotic AVF and investigate the underlying molecular mechanisms. METHODS: Forty-four patients undergoing surgery for AVF creation were examined; ten presented AVF failure, with histological-proven AVF stenosis. RESULTS: In stenotic AVF we observed a significant increase of adventitia extracellular matrix deposition and alpha-smooth muscle actin (α-SMA)+ cell numbers; most of these cells were myofibroblast (α-SMA+/vimentin+). Phosphorylated platelet-derived growth factor β receptor (p-PDGFRβ) was significantly increased within the adventitia of stenotic compared to native AVF, along with a marked increase in the phosphorylation of Akt and ERK, two key kinases in PDGFRβ signalling. Myofibroblasts were the main cell type associated with the activation of p-PDGFRβ. At the same time, we observed a significant adventitial vessels rarefaction in stenotic AVF, as demonstrated by a reduced CD34 expression. This event was associated with a marked reduction in the expression of KDR/fetal liver kinase-1, the main vascular endothelial growth factor receptor. The degree of adventitial fibrosis was directly correlated with the extent of adventitial α-SMA and inversely associated with adventitial CD34 expression. Finally, we observed an increase in CD34+/α-SMA+ cells within the adventitia of failed AVF. CONCLUSION: This study suggests that AVF failure is associated with an increased adventitial fibrosis, myofibroblast activation and capillary rarefaction, potentially linked with endothelial-to-mesenchymal transition. In this scenario, our data suggest that PDGF may play a pathogenic role.

Autore Pugliese

• Pertosa Giovanni Battista , Castellano Giuseppe , Gesualdo Loreto

Tutti gli autori

• LOVERRE A.;DIVELLA C.;PERTOSA G.B.;CASTELLANO G.;GESUALDO L.;CARIELLO M.;SIMONE S.

Titolo volume/Rivista

Non Disponibile

Anno di pubblicazione

2014

ISSN

1121-8428

ISBN

Non Disponibile

Numero di citazioni Wos

Nessuna citazione

Ultimo Aggiornamento Citazioni

Non Disponibile

Numero di citazioni Scopus

11

Ultimo Aggiornamento Citazioni

Non Disponibile

Settori ERC

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Codici ASJC

Non Disponibile