Synovial fluid collagenase in patients with destructive arthritis of the shoulder joint

Biochemical markers in the synovial fluid of glenohumeral joints from patients with rotator cuff tear

It is known that rotator cuff tears are sometimes accompanied by joint destruction. Our purpose was to elucidate the pathology with this condition. Thirty-two synovial fluid (SF) samples aspirated from the glenohumeral joints of patients with rotator cuff tears, including 7 with partial-thickness and 25 with full-thickness tears of the rotator cuff (10 massive and 15 isolated supraspinatus tendon (SSp) tears), were examined. Collagenase (MMP-1), stromelysin 1 (MMP-3), tissue inhibitor of metalloproteinases-1 (TIMP-1) and carboxy-terminal type II procollagen peptide (pCOL Il-C) were measured in the SF using the respective sandwich enzyme immunoassays. Glycosaminoglycan (GAG) was also quantified with a cationic dye binding method using 1,9-dimethylmethylene blue. Levels of any molecules except pCOL II-C in the SF appeared to be higher in full-thickness tears than those in partial-thickness tears. Moreover, levels of MMP-1, MMP-3 and GAG in the SF were significantly higher in massive tears of the rotator cuff in comparison with those in isolated SSp tears. Such significance was not observed in the levels of TIMP-1 or pCOL II C in the SF. We examined the relation of those levels with operative findings or clinical parameters from full-thickness tears, and observed significant correlations of the tear size with the levels of MMP-1, MMP-3 and GAG in the SF. Although these marker molecules in SF do not always originate from cartilage, our results may indicate the potential for accelerated cartilage-degrading activity in the glenohumeral joint in massive tears of the rotator cuff.

Can non-steroidal anti-inflammatory drugs act as metalloproteinase modulators? An in-vitro study of inhibition of collagenase activity

The in-vitro effects of some non-steroidal anti-inflammatory drugs and some analgesic drugs on collagenase activity were studied by use of a self-quenched fluorogenic esapeptide as substrate. The increased fluorescence signal arising as a result of peptide cleavage by collagenase was recorded and related to the inhibitory potency of the drugs. The effective concentrations in collagenase modulation were also correlated with the levels of the drugs in the plasma and synovial fluids of patients receiving therapeutic doses. Six of the tested drugs, nimesulide, piroxicam, tolmetin, meloxicam, sulindac and sodium meclofenamate, inhibited enzyme activity with IC50 values (concentrations resulting in 50% inhibition) ranging from 1.9 to 28.2 microM and Ki (apparent inhibition constant) ranging from 0.83 to 21.8 microM. Much of the activity was restored after dialysis of the enzyme-drug complex, demonstrating the reversibility of the effect. Although these results indicate that some anti-inflammatory drugs could modulate enzymatic activity involved in the degradation of the extracellular matrix, their possible pharmacological involvement as collagenase inhibitors in collagen degradative diseases remains to be assessed by clinical studies.

Crystals and arthritis

Monosodium urate, calcium pyrophosphate dihydrate, and basic calcium phosphate (carbonate-substituted hydroxyapatite and octacalcium phosphate) crystal aggregates are associated with gout, pseudogout, and cartilage degeneration (osteoarthritis, Milwaukee Shoulder/Knee Syndrome), respectively. Hyperuricemia is a frequent but nonspecific and inconstant feature of gout just as an elevated synovial fluid inorganic pyrophosphate level is an inconstant feature of pseudogout. Monosodium urate, calcium pyrophosphate dihydrate, or basic calcium phosphate crystals can cause acute inflammation associated with phagocytosis by neutrophilic leukocytes. Each induces neutral protease synthesis and secretion and arachidonic acid metabolism by synoviocytes and macrophages in a dose-dependent fashion, postulated to produce the damage to bone, cartilage, and other joint tissues that is perceived clinically as tophaceous destruction or degenerative joint disease. Crystals containing calcium are potent mitogens. All three types of crystals are more common in older persons and will attract additional attention as the mean age of our population increases. Gout is perhaps the most treatable disease in medicine, although mistakes in diagnosis and in choice of appropriate therapy are very common. Acute pseudogout and acute calcific periarthritis are readily treated medically, but the chronic effects of crystals containing calcium are not. New approaches using drugs derived from scientific study of the biologic effects of these crystals may become useful therapeutically.

The measurement of collagenase, tissue inhibitor of metalloproteinases (TIMP), and collagenase-TIMP complex in synovial fluids from patients with osteoarthritis and rheumatoid arthritis

OBJECTIVE

To compare the levels of collagenase, tissue inhibitor of metalloproteinases (TIMP), and collagenase-TIMP complex in synovial fluid (SF) from patients with rheumatoid arthritis (RA) and patients with osteoarthritis (OA). This study aims to clarify existing data from previously used enzyme or inhibitor activity assays performed following separation by gel filtration, by using a 1-step enzyme-linked immunosorbent assay (ELISA) for each component.

METHODS

Total collagenase, free TIMP, and collagenase-TIMP complex were measured using a newly developed, specific double-antibody sandwich ELISA:

RESULTS

Levels of both collagenase and TIMP were significantly higher in RA patients (collagenase 1,560 +/- 150 ng/ml [mean +/- SEM], TIMP 1,610 +/- 130 ng/ml; n = 80) than OA patients (collagenase 420 +/- 90 ng/ml, TIMP 1,050 +/- 60 ng/ml; n = 80), with the difference being especially striking for collagenase. Sixteen RA fluids had detectable levels of collagenase-TIMP complex, compared with only 3 OA fluids.

CONCLUSION

The level of total collagenase in SF is greater in RA than OA, while levels of free TIMP show more overlap between the 2 diseases; this may simply reflect the increased inflammation seen in RA, or it may reflect a different disease mechanism.

Basic calcium phosphate crystals cause coordinate induction and secretion of collagenase and stromelysin

Synovial fluid basic calcium phosphate crystals (BCP) are often found in severely degenerated joints. Crystalline BCP is a growth factor stimulating fibroblast mitogenesis and acting as a competence factor similar to platelet-derived growth factor. In human fibroblasts (HF), the synthesis of collagenase and stromelysin is coordinately induced after stimulation with a variety of cytokines and growth factors. We sought to determine whether BCP, like other growth factors, might induce proteases that would damage articular tissue. Northern blot analysis of mRNA for collagenase and stromelysin in HF stimulated with BCP was performed. Secreted enzymes were analyzed by immunoblot using a monoclonal antibody to collagenase and by immunoprecipitation using a polyclonal antibody to stromelysin. Stromelysin activity was confirmed using casein substrate gels. A significant, dose-dependent accumulation of collagenase and stromelysin message was evident after 4 h and continued for at least 24 h in BCP-stimulated cultures. Forty-nine and 54 kD proteins immunoreacting with collagenase antibody were identified in the conditioned media (CM) from BCP-stimulated cultures while 50 and 55 kD proteins were identified by immunoprecipitation with stromelysin antibody. Collagenase activity was increased significantly in the CM from BCP treated cells; casein substrate gels showed casein degrading bands at molecular weights consistent with stromelysin. BCP stimulates coordinate induction of collagenase and stromelysin which may mediate the joint destruction associated with these crystals.

Basic calcium phosphate crystals stimulate cell proliferation and collagenase message accumulation in cultured adult articular chondrocytes

OBJECTIVE

To investigate BCP (basic calcium phosphate) crystal-stimulated mitogenesis and collagenase gene transcription in primary cultures of porcine chondrocytes.

METHODS

The role of protein kinases in BCP crystal-stimulated DNA synthesis was investigated using thymidine incorporation, kinase inhibitors, and protein kinase C (PKC) assays. Northern blot analysis was used to determine the levels of collagenase c-fos and c-jun message.

RESULTS

BCP crystals stimulated chondrocyte proliferation in a PKC-dependent manner. Increased levels of collagenase message were preceded by an increased accumulation of c-fos, but not c-jun.

CONCLUSION

BCP crystals could contribute to the abnormal chondrocyte proliferation and collagenase secretion observed in some rheumatic diseases.

Detection of Stromelysin and Collagenase in Synovial Fluid From Patients with Rheumatoid Arthritis and Posttraumatic Knee Injury

OBJECTIVE

To quantify stromelysin and collagenase in synovial fluid (SF) from patients with rheumatoid arthritis (RA) or traumatic knee injury.

METHODS

Stromelysin and collagenase were measured in the SF of 33 patients with RA or posttraumatic knee injury, using specific double-antibody sandwich enzyme-linked immunosorbent assays. Stromelysin was fractionated from representative SF, and the molecular form was identified by immunoblot analysis.

RESULTS

The stromelysin concentration was approximately 20-fold higher than the collagenase concentration in the fluids from patients with RA and approximately 8-fold higher in the fluids from patients with traumatic injury. For both metalloproteinases, there was a higher enzyme concentration in RA SF than in the SF from patients with trauma (stromelysin 40.1 +/- 26 micrograms/ml [mean +/- SD] in RA SF, 8.5 +/- 15 micrograms/ml in trauma SF; collagenase 2.2 +/- 3.3 micrograms/ml in RA SF, 1.1 +/- 2.3 micrograms/ml in trauma SF). The majority of the stromelysin within the SF bound to reactive red-agarose and was identified as prostromelysin based on electrophoretic mobility and immunoblotting with monospecific antibodies.

CONCLUSION

The finding of high levels of stromelysin in SF from patients with RA supports the proposal that this enzyme may play a role in the connective tissue degradation observed in this disease.

The mitogenic response to stimulation with basic calcium phosphate crystals is accompanied by induction and secretion of collagenase in human fibroblasts

Synovial fluid basic calcium phosphate (BCP) crystals are associated with severe destructive arthropathies that are characterized by synovial proliferation and digestion of articular collagenous structures. BCP crystals are potent mitogens, which may account for this proliferation. The role of collagenase in articular degradation is controversial because, despite the massive loss of collagen, no studies have confirmed collagenolytic activity in synovial fluid, as originally reported. We investigated collagenase messenger RNA induction and enzyme activity in human foreskin fibroblasts proliferating in response to stimulation with BCP crystals, and analyzed the associated secreted proteins. Northern blots revealed a dose-dependent accumulation of collagenase message, evident by 4 hours and continuing to at least 36 hours, in BCP-stimulated cultures. One- and 2-dimensional polyacrylamide gel electrophoresis of conditioned media from BCP crystal-stimulated cultures revealed the selective induction of 2 proteins with molecular weight and pI values consistent with those of collagenase. Increased enzyme activity was also found. Thus, the mitogenic response of fibroblasts to BCP crystals is accompanied by collagenase induction and secretion, supporting the hypothesis that they act as a mediator of joint destruction in BCP crystal-associated arthropathies.

Immunoassays for the detection of human collagenase, stromelysin, tissue inhibitor of metalloproteinases (TIMP) and enzyme-inhibitor complexes

Immunoassays have been developed for human collagenase, stromelysin, tissue inhibitor of metalloproteinases (TIMP) and TIMP complexed with both of the active enzymes. Selection of antibodies of defined specificity enabled measurement of both the pro and active forms of the metalloproteinase. Free TIMP was quantified by the selection of a monoclonal antibody which did not recognise TIMP when complexed with metalloproteinases. Detection of enzyme-inhibitor complexes was achieved by capturing the TIMP component of the complex and revealing the metalloenzyme using specific antibodies.