Modulation of matrix metalloprotease 13 (collagenase 3) gene expression in equine chondrocytes by interleukin 1 and corticosteroids.

The research explored the production of Matrix Metalloprotease 13 (MMP-13), also known as collagenase 3, in equine (horse) chondrocytes (cartilage cells), and how its production is influenced by the human protein Interleukin 1 beta (rhIL-1 beta) and corticosteroids. The findings suggest a possible role for this enzyme in cartilage degradation in horses suffering from arthritis.

Experimental Procedure

• Researchers isolated chondrocytes from horses and cultured them in a laboratory setup.
• The chondrocytes were stimulated with rhIL-1 beta, a protein active in inflammation and immune responses.
• The resultant RNA was extracted, purified, and then converted back into DNA.
• Using a specific set of primers, the DNA was tested for the presence of MMP-13 by amplifying it using polymerase chain reaction (PCR).
• The DNA sequence of interest was then cloned into bacterial vectors for further analysis and sequencing, and to make a probe labeled with digoxigenin (a steroid used for immunochemical detection in labeling antibodies and nucleic acids).
• Similarly cultured chondrocytes were then treated with rhIL-1 beta in the presence or absence of dexamethasone or methylprednisolone acetate (types of corticosteroids), alongside controls.
• The cellular RNA was consequently extracted, laid out on agarose gels, and subjected to northern blot analysis using the equine-specific MMP-13 probe. Northern blotting is a technique used to detect specific RNA molecules among a mixture of RNA.

Results

• The research team successfully isolated a fragment of the equine MMP-13 gene that had a high percentage of homology (93%) with the human MMP-13 gene, indicating significant similarity.
• The study showed that the presence of rhIL-1 significantly increased the production of MMP-13 by the equine cartilage cells.
• Conversely, methylprednisolone acetate was found to inhibit the stimulatory effects of rhIL-1 in a dose-dependent manner. This inhibitory effect was found to be significant at a concentration of 10(-5)M.

Conclusion

• The study presents novel information about the existence and level of expression of the MMP-13 gene within equine chondrocytes.
• These findings further suggest a potential role for MMP-13 in the degradation of cartilage matrix in horses affected by arthritis, thereby providing targets for future investigation and potential drug development.