Tn. Trumble et al., Synovial fluid gelatinase concentrations and matrix metalloproteinase and cytokine expression in naturally occurring joint disease in horses, AM J VET RE, 62(9), 2001, pp. 1467-1477
Objectives-To determine concentrations of matrix metalloproteinase (MMP)-2
and -9 in synovial fluid; and mRNA expression of MMP-1, -13, and -3; interl
eukin[IL]-1 alpha and beta; and tumor necrosis factor(TNF)-alpha in synovia
l membrane and articular cartilage from horses with naturally occurring joi
nt disease.
Sample Population-Synovial fluid (n=76), synovial membrane (59), and articu
lar cartilage (45) from 5 clinically normal horses and 55 horses with joint
disease categorized as traumatic (acute [AT] or chronic [CT]), osteochondr
itis dissecans (OCD), or septic (S).
Procedure-Synovial fluid gelatinase concentrations were analyzed, using zym
ography. Synovial membrane and articular cartilage mRNA expression for MMP-
1, -3, and -13, IL-1 alpha and beta, TNF-alpha, type-II collagen, and aggre
can were analyzed, using quantitative reverse transcriptase-polymerase chai
n reaction.
Results-Synovial fluid pro-MMP-2 concentration was significantly higher in
diseased joints than normal joints. Septic joints had significantly higher
concentrations of pro and active MMP-9. Stromelysin-1 was expressed in grea
ter than or equal to 80% of synovial membrane and articular cartilage sampl
es and was strongly influenced by age. Collagenases were rarely expressed,
with MMP-13 expressed only in diseased joints. Interleukin-1 beta expressio
n was significantly higher In all OCD samples and was influenced by age. Tu
mor necrosis factor-alpha expression was significantly higher in cartilage
from joints with AT and OCD. There was no correlation between MMP or cytoki
nes and type-II collagen or aggrecan expression.
Conclusions and Clinical Relevance-Matrix metalloproteinase-2 and -3 are ab
undant in naturally occurring joint disease and normal joints. Interleukin-
1 beta and TNF-alpha may be Important in the pathogenesis of OCD. Age affec
ts MMP and IL-1 beta concentrations.