Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
8
pubmed:dateCreated
2003-7-22
pubmed:abstractText
An increasing body of evidence suggests that proteases may play a key role in the pathogenesis of tissue fibrosis. Protease-activated receptor-2 (PAR-2) is cleaved and activated by trypsin-like proteolytic enzymes, including tryptase and activated coagulation factor X (FXa). Both these soluble mediators have been demonstrated, directly or indirectly, at the interstitial level in progressive renal diseases, including IgA nephropathy (IgAN). PAR-2 mRNA and protein levels were investigated by RT-PCR and immunohistochemistry, respectively, in 17 biopsies from IgAN patients and 10 normal kidneys. PAR-2 expression was also evaluated, by RT-PCR and western blotting, in cultured human mesangial and proximal tubular cells. Finally, gene expression of plasminogen activator inhibitor-1 (PAI-1) and TGF-beta, two powerful fibrogenic factors, was evaluated in FXa-, trypsin-, and PAR-2 activating peptide-stimulated human proximal tubular cells by Northern blot. In normal kidneys, PAR-2 gene expression was barely detectable, whereas in IgAN biopsies the mRNA levels for this protease receptor were strikingly increased and directly correlated with the extent of interstitial fibrosis. Immunohistochemical staining demonstrated that PAR-2 protein expression in IgAN biopsies was mainly localized in the proximal tubuli and within the interstitial infiltrate. Proximal tubular cells in culture expressed PAR-2. Activation of this receptor by FXa in tubular cells induced a striking increase in intracellular calcium concentration. In addition, incubation of both cell lines with trypsin, FXa, or PAR-2 activating peptide caused a marked upregulation of PAI-1 gene expression that was not counterbalanced by an increased expression of plasminogen activators. Finally, PAR-2 activation induced a significant upregulation of TGF-beta gene and protein expression in both mesangial and tubular cells. On the basis of our data, we can suggest that PAR-2 expressed by renal resident cells and activated by either mast cell tryptase or FXa may induce extracellular matrix deposition modifying the PAI-1/PA balance and inducing TGF-beta expression. These molecular mechanisms may underlie interstitial fibrosis in IgAN.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
http://linkedlifedata.com/resource/pubmed/chemical/Calcium, http://linkedlifedata.com/resource/pubmed/chemical/Factor Xa, http://linkedlifedata.com/resource/pubmed/chemical/Plasminogen, http://linkedlifedata.com/resource/pubmed/chemical/Plasminogen Activator Inhibitor 1, http://linkedlifedata.com/resource/pubmed/chemical/RNA, Messenger, http://linkedlifedata.com/resource/pubmed/chemical/RNA, Ribosomal, 18S, http://linkedlifedata.com/resource/pubmed/chemical/RNA, Ribosomal, 28S, http://linkedlifedata.com/resource/pubmed/chemical/Receptor, PAR-2, http://linkedlifedata.com/resource/pubmed/chemical/Serine Endopeptidases, http://linkedlifedata.com/resource/pubmed/chemical/Thrombin, http://linkedlifedata.com/resource/pubmed/chemical/Transforming Growth Factor beta, http://linkedlifedata.com/resource/pubmed/chemical/Trypsin, http://linkedlifedata.com/resource/pubmed/chemical/Tryptases
pubmed:status
MEDLINE
pubmed:month
Aug
pubmed:issn
1046-6673
pubmed:author
pubmed:issnType
Print
pubmed:volume
14
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
2072-83
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed-meshheading:12874461-Biopsy, pubmed-meshheading:12874461-Blotting, Northern, pubmed-meshheading:12874461-Blotting, Western, pubmed-meshheading:12874461-Calcium, pubmed-meshheading:12874461-Cell Line, pubmed-meshheading:12874461-Enzyme-Linked Immunosorbent Assay, pubmed-meshheading:12874461-Extracellular Matrix, pubmed-meshheading:12874461-Factor Xa, pubmed-meshheading:12874461-Fibrosis, pubmed-meshheading:12874461-Glomerular Mesangium, pubmed-meshheading:12874461-Glomerulonephritis, pubmed-meshheading:12874461-Glomerulonephritis, IGA, pubmed-meshheading:12874461-Humans, pubmed-meshheading:12874461-Immunohistochemistry, pubmed-meshheading:12874461-Kidney, pubmed-meshheading:12874461-Kidney Diseases, pubmed-meshheading:12874461-Kidney Tubules, pubmed-meshheading:12874461-Plasminogen, pubmed-meshheading:12874461-Plasminogen Activator Inhibitor 1, pubmed-meshheading:12874461-RNA, Messenger, pubmed-meshheading:12874461-RNA, Ribosomal, 18S, pubmed-meshheading:12874461-RNA, Ribosomal, 28S, pubmed-meshheading:12874461-Receptor, PAR-2, pubmed-meshheading:12874461-Reverse Transcriptase Polymerase Chain Reaction, pubmed-meshheading:12874461-Serine Endopeptidases, pubmed-meshheading:12874461-Thrombin, pubmed-meshheading:12874461-Time Factors, pubmed-meshheading:12874461-Transforming Growth Factor beta, pubmed-meshheading:12874461-Trypsin, pubmed-meshheading:12874461-Tryptases, pubmed-meshheading:12874461-Up-Regulation
pubmed:year
2003
pubmed:articleTitle
Protease-activated receptor-2 expression in IgA nephropathy: a potential role in the pathogenesis of interstitial fibrosis.
pubmed:affiliation
Division of Nephrology, Department of Emergency and Transplantation, University of Bari, Policlinico, Bari. g.grandaliano@nephro.uniba.it
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't