Several studies have demonstrated that
matrix metalloproteinases (
MMPs) are frequently implicated in the destruction of articular cartilage in
arthritis. The control of
MMP activity is dependent on the local concentration of tissue inhibitors of
metalloproteinases (TIMPs), and the imbalance of the
enzyme-to-inhibitor ratios plays an important role in the remodeling of articular tissues. Some
cytokines such as
interleukin (IL)-1 and
tumor necrosis factor (
TNF)-alpha which regulate leukocyte activities, promote
MMP secretion and, as a consequence, cartilage degradation. The aim of the present study was to investigate whether a natural treatment is effective in reducing cartilage
inflammation and degradation by influencing
MMP and TIMP serum levels. Eighty patients with
osteoarthritis (OA) were enrolled in the trial and were divided into group A (30 patients who did not undergo
mud bath therapy), group B (28 patients repeating
mud bath therapy more than 5 times and less than 10) and group C (22 patients repeating
mud bath therapy more than 10 times). Blood samples were obtained from all the patients for assay of MMP-1, -2, -3, -8 and -9 and
TIMP-1 and -2. The parameters were determined by an ELISA technique. Statistical indexes were calculated for each parameter and mean values were compared. The differences between mean values of MMP-3, -8 and -9 were statistically significant between group A and the treated groups (B and C). Analysis of variance established a significant difference (p < 0.05) between groups A and C in mean serum levels of MMP-8, MMP-9 showed a statistically significant difference (p < 0.05) in mean serum concentration between groups A and B. Regression analysis showed a very high R2 between MMP-2 and
TIMP-2. One of the most interesting findings in this study was that MMP-3 serum levels were significantly lower in the treated groups, since this
enzyme plays an important role in cartilage degradation, suggesting that
mud bath therapy contributes to matrix integrity in OA cartilage. In contrast, MMP-8 and -9 were higher in the treated subjects and no correlation with TIMPs was evident. One possible explanation is that these
enzymes are required for the efficient degradation and removal of already compromised cartilage matrix and that they operate as part of a matrix turnover and repair process. In conclusion, our data suggest that
mud bath therapy alone is not able to influence chondrocyte metabolic activity in the advanced phases of OA. There could be a synergic and sequential association with pharmacologic
therapy and/or interventions.