Methylprednisolone Acetate Mitigates Il1 Beta Induced Changes In Matrix Metalloproteinase Gene Expression In Skeletally Immature Ovine Explant Knee Tissues

Objective and design This study aimed at evaluating the effect of methylprednisolone (MPA) on messenger ribonucleic acid (mRNA) expression levels in immature ovine knee joint tissue explants following interleukin (IL)1 beta induction and to assess responsiveness of the explants. Material or subjects Explants were harvested from the articular cartilage, synovium, and infrapatellar fat pad (IPFP) from immature female sheep. Treatment Methylprednisolone. Methods The samples were allocated into six groups: (1) control, (2) MPA (10(-3) M), (3) MPA (10(-4) M), (4) IL1 beta, (5) IL1 beta + 10(-3) M MPA, or (6) IL1 beta + 10(-4) M MPA. mRNA expression levels for molecules relevant to inflammation, cartilage degradation/anabolism, activation of innate immunity, and adipose tissue/hormones were quantified. Fold changes with MPA treatment were compared via the comparative C-T method. Results Methylprednisolone treatment significantly suppressed MMPs consistently across the cartilage (MMP1, MMP3, and MMP13), synovium (MMP1 and MMP3), and IPFP (MMP13) (all p < 0.05). Other genes that were less consistently suppressed include endogenous IL1 beta (cartilage) and IL6 (IPFP) (all p < 0.05), and others not affected either by IL-1 exposure or subsequent MPA include TGF beta 1, TLR4, and adipose-related molecules. Conclusions Methylprednisolone significantly mitigated IL1 beta induced mRNA expression for MMPs in the immature cartilage, synovium, and IPFP, but the extent of the responsiveness was tissue-, location-, and gene-specific.