Extracellular matrix remodelling in response to venous hypertension: proteomics of human varicose veins

Abstract

AimsExtracellular matrix remodelling has been implicated in a number of vascular conditions, including venous hypertension and varicose veins. However, to date, no systematic analysis of matrix remodelling in human veins has been performed.Methods and resultsTo understand the consequences of venous hypertension, normal and varicose veins were evaluated using proteomics approaches targeting the extracellular matrix. Varicose saphenous veins removed during phlebectomy and normal saphenous veins obtained during coronary artery bypass surgery were collected for proteomics analysis. Extracellular matrix proteins were enriched from venous tissues. The proteomics analysis revealed the presence of >150 extracellular matrix proteins, of which 48 had not been previously detected in venous tissue. Extracellular matrix remodelling in varicose veins was characterized by a loss of aggrecan and several small leucine-rich proteoglycans and a compensatory increase in collagen I and laminins. Gene expression analysis of the same tissues suggested that the remodelling process associated with venous hypertension predominantly occurs at the protein rather than the transcript level. The loss of aggrecan in varicose veins was paralleled by a reduced expression of aggrecanases. Chymase and tryptase β1 were among the up-regulated proteases. The effect of these serine proteases on the venous extracellular matrix was further explored by incubating normal saphenous veins with recombinant enzymes. Proteomics analysis revealed extensive extracellular matrix degradation after digestion with tryptase β1. In comparison, chymase was less potent and degraded predominantly basement membrane-associated proteins.ConclusionThe present proteomics study provides unprecedented insights into the expression and degradation of structural and regulatory components of the vascular extracellular matrix in varicosis.

Comparative proteomic assessment of matrisome enrichment methodologies

“…In the deep proteomic study of mouse lung ECM by Schiller et al [16], only 53 of a total 264 matrisome-associated proteins were found to be enriched in the insoluble fraction after quantitative detergent solubility profiling. Similarly, in a study of the human ventricle ECM performed by Barallobre-Barreiro et al [46], a higher abundance of matrisome-associated proteins such as S100 proteins or ECM peptidases was found in the soluble fraction. Our data highlight that in-depth proteomic analysis of non-enriched samples is currently the best available tool for the analysis of this class of proteins; however, further development of new enrichment strategies to better isolate matrisome-associated proteins with improved sequence coverage is necessary.…”

Short‐ and long‐term outcomes of laser haemorrhoidoplasty for grade II–III haemorrhoidal disease

“…The two time points of 30 and 60 days did not differ significantly when considering all categories of improvement ( P = 0.29). However, results suggest a tendency of improvement between 30 and 60 days which might be due to the prolonged time necessary for remodelling of initial pathological changes in the extracellular matrix in varicose veins .…”

Systems biology—opportunities and challenges: the application of proteomics to study the cardiovascular extracellular matrix

“…Over the past years our group has focused on ECM remodelling in cardiac 2 , 52 , 60 , 61 and vascular tissues 3 , 4 , 57 , 59 using proteomics. In a previous review, we highlighted the potential of proteomics when applied to systems biology 62 .…”

“…demonstrated in a study that also included ECM biomarkers of fibrosis. Moreover, targeted proteomics constitutes a robust method to validate findings obtained from discovery experiments ( Figure 4 ) 3 Figure 4MS strategies for ECM characterisation.…”

“…The specifics of lysine hydroxylation are beyond the scope of this review, and are discussed elsewhere 80 . Adding hydroxylation as a variable modification, improves identification and quantification of collagen levels in disease 3 , 68 . Ascorbic acid (vitamin C) is a key cofactor for prolyl-4-hydroxylase, and its deficiency causes defects in collagen assembly 81 .…”