THE ACTIVATION OF MATRIX METALLOPROTEINASES AND CHONDROCYTE DIFFERENTIATION, WHICH ACCOMPANIES THE INDUCTION OF COLLAGEN DECOMPOSITION UNDER THE ACTION OF COLLAGEN PEPTIDE IN THE CARTILAGE OFHEALTHY INDIVIDUALS

• Main Authors: Elena Vasil'evna Chetina, Elena Vasilyevna Chetina
• Format: Article
• Language: Russian
• Published: IMA-PRESS LLC 2010-10-01
• Series: Научно-практическая ревматология
• Subjects: articular cartilage; gene expression; chondrocyte hypertrophy; collagenase; type ii collagen; peptide
• Online Access: https://rsp.mediar-press.net/rsp/article/view/868

Objective: To study the effect of type II collagen peptide (CB12-2) that is able to induce the collagen decomposition in the knee articular cartilage explants, which activates matrix metalloproteinase (MMP) and articular chondrocyte differentiation. Material and methods. Human cartilage explants were cultured in the presence of CB12-2 (amino acid residues 195-218) at a concentration of 10 μM. Type II collagen decomposition was evaluated by enzyme immunoassay. Immunohistochemical assay of type X collagen (C0L10A1) used frozen cartilage sections. Apoptotic activity was measured by terminal deoxynucleotidyl transferase-mediated dUPTnick end-labeling method (TUNEL). Gene expressions were determined by semiquantitative reverse transcription polymerase chain reaction (RT-PCR). Results. CB12-2 at high, but naturally occurring concentrations (10 μM) induced type II collagen decomposition by collagenase in the cartilage explants from a healthy individual. The peptide caused an increase in the expression of MMP 13, 1, 9, MT1-MMP, and the genes associated with the differentiation of embryo chondrocytes in the growth plate - transforming growth factor (TGF) β1/2, sex-determining region Y-box 9 (Sox9), Indian hedgehog (Ihh), parathyroid hormone-related peptide (PTHrP), fibroblast growth factor (FGF-2); a marker for proliferation of cyclin B2 and cytokines of tumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1Я). At the same time the increased expression of the chondrocyte hypertrophy marker C0L10A1 was accompanied by enhanced staining for type X collagen in the frozen cartilage sections whereas the number of TUNEL-positive cells increased in the cartilage surface area as the expression of the apoptotic marker caspase 3 became higher. Conclusion. This study has shown that the induction of collagenase activity by CB12-2 in the human articular cartilage chondrocytes is attended by terminal differentiation/hypertrophy of these cells. The terminal differentiation of chondrocytes may be one of the mechanisms of chondrolysis in osteoarthrosis since it naturally occurs not only in endochondrial ossification, but also in the development of pathology.