Matrix metalloproteinase-2 and -9 are activated in joint diseases.

The research article talks about a study conducted to examine the levels and activation of enzymes MMP-2 and MMP-9 in healthy and diseased horse joints, and the influence of IL-1beta concentrations on these enzymes. The idea was to verify if activation of these enzymes plays a key role in development of joint diseases.

Study on Gelatinase MMPs

• The key subjects of this study were Matrix Metalloproteinases (MMPs -2 and -9), which are enzymes capable of breaking down extracellular matrix. Specifically, the researchers wanted to understand their activation status in healthy and diseased horse joint tissues.
• The study also sought to understand how the levels and activation status of the enzymes reacted to increasing levels of IL-1beta, a pro-inflammatory cytokine believed to influence the activity of these enzymes.

Test Hypothesis

• The hypothesis wasn’t vague; it proposed that activation of MMPs is a fundamental stage in the development of joint diseases. The hypothesis further suggested that this activation is probably triggered by the cytokine IL-1.

Key Findings of the Research

• Chemistry work and experimentation allowed determining the molecular weights of the dormant and active versions of MMP -2 and -9.
• Experimentation revealed that normal equine joint tissues produced only inactive MMP-2, while joint tissues from diseased joints produced both inactive and activated MMP-2 along with the MMP-9 enzyme in both its single and double forms. However, activated MMP-9 was found inconsistently.
• Different samples of tissue and isolated cells reacted differently to IL-1beta treatment. The most consistent finding was a mild increase in both inactive and active forms of MMP-2. Notably, tissues and cells from the synovial membrane and chondrocyte cell cultures demonstrated a dose-dependent increase in the levels of MMP-2 and MMP-9.

Results of the Study

• This research supports the original hypothesis that the activation of MMPs is occurring in joint disease. Not only there was an increase in MMP production on exposure to IL-1beta, but there was also an increase in the amount of activated enzyme released.
• This study forms the basis for more detailed research into the role of MMP activation in joint diseases. With these findings, potential therapeutic agents that inhibit MMP activation may be explored for the treatment and prevention of joint diseases.