Purpose: To use proteomic analysis to identify up- and downregulated proteins in early venous stenosis formation in a porcine model of hemodialysis graft failure.
Materials and methods: Pigs had chronic renal insufficiency created by subtotal renal infarction caused by renal artery embolization. Arteriovenous polytetrafluoroethylene grafts were placed 28 days later and the animals were killed after a further 3 days (n = 4), 7 days (n = 4), or 14 days (n = 4). Proteomic analysis with isotope-coded affinity tags and multidimensional liquid chromatography followed by tandem mass spectrometry was performed on the venous stenosis and control vessels. Expression of proteins was further confirmed by Western blot analysis. The blood urea nitrogen (BUN) and creatinine levels were determined before renal artery embolization and at the time of graft placement.
Results: At graft placement, mean BUN and creatinine levels were significantly higher than before embolization (P < .05). Six proteins were identified that were common to all four animals at the same time point. Five proteins (alpha-fetoprotein, fetuin A, macrophage migration inhibitory factor, pyruvate dehydrogenase E1 component, and lactoferrin) were upregulated and one protein (decorin) was downregulated. Expression of macrophage migration inhibitory factor, alpha-fetoprotein, and lactoferrin was further validated with Western blotting. By day 14, lactoferrin and fetuin-A expression were increased significantly in early venous stenosis formation.
Conclusions: Significantly increased expression of lactoferrin and fetuin-A were observed in early venous stenosis by day 14. Understanding the role of lactoferrin and fetuin-A in hemodialysis vascular access failure could help in improving outcomes in patients undergoing hemodialysis.