title: Proteomic and redox-proteomic evaluation of homogentisic acid and ascorbic acid effects on human articular chondrocytes.
abstract: Alkaptonuria (AKU) is a rare genetic disease associated with the accumulation of homogentisic acid (HGA) and its oxidized/polymerized products in connective tissues up to the deposition of melanin-like pigments (ochronosis). Since little is known on the effects of HGA and its metabolites on articular cells, we carried out a proteomic and redox-proteomic analysis to investigate how HGA and ascorbic acid (ASC) affect the human chondrocytic protein repertoire. We settled up an in vitro model using a human chondrocytic cell line to evaluate the effects of 0.33 mM HGA, alone or combined with ASC. We found that HGA and ASC significantly affect the levels of proteins with specific functions in protein folding, cell organization and, notably, stress response and cell defense. Increased protein carbonyls levels were found either in HGA or ASC treated cells, and evidences produced in this paper support the hypothesis that HGA-induced stress might be mediated by protein oxidation. Our finding can lay the basis towards the settling up of more sophisticated models to study AKU and ochronosis.
authors.affiliation: Dipartimento di Biologia Molecolare, Università degli Studi di Siena, via Fiorentina 1, 53100 Siena (SI), Italy.
authors.forename: Daniela
authors.initials: D
authors.lastname: Braconi
authors.forename: Marcella
authors.initials: M
authors.lastname: Laschi
authors.forename: Adam M
authors.initials: AM
authors.lastname: Taylor
authors.forename: Giulia
authors.initials: G
authors.lastname: Bernardini
authors.forename: Adriano
authors.initials: A
authors.lastname: Spreafico
authors.forename: Laura
authors.initials: L
authors.lastname: Tinti
authors.forename: James A
authors.initials: JA
authors.lastname: Gallagher
authors.forename: Annalisa
authors.initials: A
authors.lastname: Santucci
mesh_terms: D001205:Ascorbic Acid / Q000494:pharmacology*; D002358:Cartilage, Articular / Q000166:cytology*; D002460:Cell Line; D002470:Cell Survival / Q000187:drug effects; D019902:Chondrocytes / Q000187:drug effects* / Q000378:metabolism*; D004591:Electrophoresis, Polyacrylamide Gel; D006713:Homogentisic Acid / Q000494:pharmacology*; D006801:Humans; D010084:Oxidation-Reduction; D050050:Protein Carbonylation / Q000187:drug effects; D011506:Proteins / Q000378:metabolism; D040901:Proteomics / Q000379:methods*
chemical_list: D011506:Proteins; D006713:Homogentisic Acid; D001205:Ascorbic Acid