title: Basic aminopeptidase activity is an emerging biomarker in collagen-induced rheumatoid arthritis.
abstract: The objective of this study was to investigate the catalytic activity of basic aminopeptidase (APB) and its association with periarticular edema and circulating tumor necrosis factor (TNF)-alpha and type II collagen (CII) antibodies (AACII) in a rat model of rheumatoid arthritis (RA) induced by CII (CIA). Edema does not occur in part of CII-treated, even when AACII is higher than in control. TNF-alpha is detectable only in edematous CII-treated. APB in synovial membrane is predominantly a membrane-bound activity also present in soluble form and with higher activity in edematous than in non-edematous CII-treated or control. Synovial fluid and blood plasma have lower APB in non-edematous than in edematous CII-treated or control. In peripheral blood mononuclear cells (PBMCs) the highest levels of APB are found in soluble form in control and in membrane-bound form in non-edematous CII-treated. CII treatment distinguishes two categories of rats: one with arthritic edema, high AACII, detectable TNF-alpha, high soluble and membrane-bound APB in synovial membrane and low APB in the soluble fraction of PBMCs, and another without edema and with high AACII, undetectable TNF-alpha, low APB in the synovial fluid and blood plasma and high APB in the membrane-bound fraction of PBMCs. Data suggest that APB and CIA are strongly related.
authors.affiliation: Laboratory of Pharmacology, Instituto Butantan, Av. Vital Brasil, 1500, 05503-900 São Paulo, SP, Brazil.
authors.forename: Mariana Trivilin
authors.initials: MT
authors.lastname: Mendes
authors.forename: Stephanie
authors.initials: S
authors.lastname: Murari-do-Nascimento
authors.forename: Isis Rossetti
authors.initials: IR
authors.lastname: Torrigo
authors.forename: Rafaela Fadoni
authors.initials: RF
authors.lastname: Alponti
authors.forename: Simone Cristina
authors.initials: SC
authors.lastname: Yamasaki
authors.forename: Paulo Flavio
authors.initials: PF
authors.lastname: Silveira
mesh_terms: D000626:Aminopeptidases / Q000097:blood / Q000378:metabolism*; D000818:Animals; D001169:Arthritis, Experimental / Q000201:enzymology*; D015415:Biomarkers / Q000378:metabolism; D008297:Male; D051381:Rats; D013582:Synovial Fluid / Q000201:enzymology / Q000378:metabolism; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism
chemical_list: D015415:Biomarkers; D014409:Tumor Necrosis Factor-alpha; D000626:Aminopeptidases