Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:3.4.22.32 (bromelain)
 1,025 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We have observed that treatment of rabbit synovial fibroblasts with proteolytic enzymes can induce secretion of collagenase (EC 3.4.24.7) and plasminogen activator (EC 3.4.21.-). Cells treated for 2-24 hr with plasmin, trypsin, chymotrypsin, pancreatic elastase, papain, bromelain, thermolysin, or alpha-protease but not with thrombin or neuraminidase secreted detectable amounts of collagenase within 16-48 hr. Treatment of fibroblasts with trypsin also induced secretion of plasminogen activator. Proteases initiated secretion of collagenase (up to 20 units per 10(6) cells per 24 hr) only when treatment produced decreased cell adhesion. Collagenase production did not depend on continued presence of proteolytic activity or on subsequent cell adhesion, spreading, or proliferation. Routine subculturing with crude trypsin also induced collagenase secretion by cells. Secretion of collagenase was prevented and normal spreading was obtained if the trypsinized cells were placed into medium containing fetal calf serum. Soybean trypsin inhibitor, alpha(1)-antitrypsin, bovine serum albumin, collagen, and fibronectin did not inhibit collagenase production. Although proteases that induced collagenase secretion also removed surface glycoprotein, the kinetics of induction of cell protease secretion were different from those for removal of fibronectin. Physiological inducers of secretion of collagenase and plasminogen activator by cells have not been identified. These results suggest that extracellular proteases in conjunction with plasma proteins may govern protease secretion by cells.
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PMID:Proteases induce secretion of collagenase and plasminogen activator by fibroblasts. 20 72

The hydrolytic and enzymic degradation of poly(L-lactic acid) (PLA) and poly(gamma-benzyl L-glutamate) (PBGA) films, together with a series of surface treatments, were studied, as a function of exposure time. The degradation of these polymers was monitored by weight loss, contact angle, pH changes and tensile strength studies. Glutaraldehyde treatment retained the maximum strength of PLA in buffer, followed by carbodiimide, compared with control films. On the other hand, plasma glow reversed the effect. The ability of alpha-chymotrypsin, carboxypeptidase, ficin, esterase, bromelain and leucine aminopeptidase to modulate the degradation of PLA and PBGA was also investigated. Addition of these enzymes to the polymer-buffer system reduced the tensile strength of these polymers variably. Among the six enzymes studied, leucine aminopeptidase showed the highest enzymic effect on the degradation of the glutaraldehyde-treated and bare PLA or bare PBGA films. However, glutaraldehyde-cross-linked PLA demonstrated maximum stability in buffers or in all other enzyme systems studied compared with bare PLA. It is conceivable that surface treatments on these polymers might have altered their physical and chemical configuration and the subsequent degradation properties. Surface modifications may provide new ways of controlling the biodegradation of polymers for a variety of biomedical applications.
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PMID:Effect of plasma glow, glutaraldehyde and carbodiimide treatments on the enzymic degradation of poly (L-lactic acid) and poly (gamma-benzyl-L-glutamate) films. 172 Jun 76

It has been established that a bromelain plasminogen activator will produce plasmin in rat experiments. In addition the plasmin cleaves Hageman factor in a way that leads to a strong release of kallikrein but a weak release of thrombin. A possible mechanism is suggested to explain how the body can maintain thrombin at a level too low to cause platelet aggregation but adequate to stimulate release of prostaglandins and enzymes for more than 24 hours from a single dose of the pineapple enzymes. Since bromelain therapy leads to formation of platelets with increased resistance to aggregation, it is obvious that the dominant endogenous prostaglandins being produced must be from the group that increases platelet cyclicAMP levels (prostacyclin, PGE1, etc.). The combination of fibrinolytic and antithrombic properties appear to be effective and two large scale tests on heart patients have shown a practically complete elimination of thrombosis.
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PMID:Fibrinolytic and antithrombotic action of bromelain may eliminate thrombosis in heart patients. 625 12