Transforming Growth Factor-β۱ Preserves Bovine Nasal Cartilage against Degradation Induced by Interleukin-۱α in Explant Culture

Background and Aims: Chondrocytes and their differentiation play a central role in joint diseases. Effect of the transforming growth factor (TGF)-β۱ on chondrocyte characteristics and differentiation is not clearly understood. This study was undertaken to investigate the effects of TGF-β۱ on tissue characteristics and morphology of chondrocytes against degradation induced by interleukin (IL)-lα in bovine nasal cartilage (BNC) explant culture. Materials and Methods: BNC explants were cultured in DMEM and samples were divided into four groups. In group A (control); samples were only cultured in DMEM and group B; was treated with IL-۱α (۱۰ ng/ml), group C; treated with TGF-β۱ (۱۰ ng/ml) and group D; treated with IL-۱α (۱۰ ng/ml) + TGF-β۱ (۱۰ ng/ml) for ۱۴ days. At days ۳, ۷ and ۱۴ the media were collected and replaced with fresh media. Then, samples were harvested on days ۳, ۷ and ۱۴ and chondrocyte morphology was assessed by invert microscopy. We used Masson's Trichrome stain to visualize collagen distribution and synthesis, and Safranin O and Alician blue to highlight the proteoglycan content. Results: In the presence of IL-lα, most of the chondrocytes were transformed into fibroblast-like morphology with pyknotic nuclei at day ۱۴ and proteoglycan and collagen in extracellular matrix (ECM) were destructed at this time. In the presence of TGF-β۱, chondrocytes preserved their ordinary normal features. Also, TGF-β۱ inhibited collagen and proteoglycan destruction and cartilage ECM showed normal characteristics. Conclusions: IL-۱α induced significant morphological changes in chondrocytes and increased the destruction of ECM. TGF-β۱ could strongly preserves cartilage from IL-۱α degradation effects.

Keywords:

Bovine nasal cartilage , Chondrocyte , IL-۱α , TGF-β , کندروسیت , اینترلوکین ۱ آلفا , فاکتور رشد تغییر دهنده β , غضروف بینی گاو