Determination of MMP-2 and -9 activities in synovial fluid of horses with osteoarthritic and arthritic joint diseases using gelatin zymography and immunocapture activity assays.

This research examines the presence and activity levels of two enzymes — matrix metalloproteinases (MMPs)-2 and -9 — in joint fluid of horses affected by two different types of joint diseases. The researchers used testing methods to find that these enzymes may serve as markers for specific joint conditions.

Objective and Methodology

• This research purposed to explore the clinical relevance of MMP-2 and -9 enzyme activities in synovial fluid (joint fluid) of horses suffering from varied forms of joint diseases.
• To pursue this objective, the researchers used two specific techniques – gelatin zymography (a method for detecting enzyme activity) and MMP-2 and -9 immunocapture activity assays (tests that are used to capture and detect these enzymes).
• The researchers studied synovial fluid from healthy joints (controls) and joints with two different types of joint disease: aseptic joint disease (AJD, inflammation not caused my microorganisms) and septic arthritis (SA, inflammation caused by infection).
• The activities of MMP-2 and -9 were also measured in samples from cases of SA to scrutinize the disease’s progress.

Results

• Zymographic analysis disclosed considerably higher latent MMP-2 activity in samples from AJD and SA when compared to healthy joints.
• Similarly, samples from SA showed significantly higher monomeric latent MMP-9 activity than controls and all other affected joints.
• MMP-9 activity was found in small amounts due to the active and dimer form in samples from SA, whereas no such bands were present in AJD and control samples.
• The immunocapture activity assay analysis demonstrated markedly elevated MMP-2 and -9 activity in joints from SA cases compared to healthy control and AJD samples.
• MMP-2 activity was also noticeably increased in AJD samples when compared to control samples.
• The action of both MMPs decreased in SA-affected joints over the course of successful therapy.

Conclusions

• The research data confirmed the elevated levels of MMP-2 and -9 in equine joint diseases.
• The study showed that immunocapture activity assays were an effective tool for quantitative measurement of MMP-2 and -9 activity levels in synovial fluid of horses.
• MMP-2 and -9 activities may be useful clinical indicators of SA, while MMP-2 activity could serve as a marker for AJD.
• The results of this study suggest potential clinical use of MMP-2 and -9 as additional diagnostic tools.
• However, more research is necessary to validate the clinical significance of MMP activity in the progression of various horse joint diseases.