Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound   Target Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound

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Query: EC:3.4.24.3 (collagenase)
18,340 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Roxarsone and monensin are common poultry feed additives that are used alone or in combination with other drugs to improve growth and feed utilization in young birds. The effects of monensin and roxarsone on the physiology of flexoral tendons of broiler chickens were examined to understand their relationships to leg weakness that have been occasionally associated with these drugs. Day-old chickens were fed either roxarsone or monensin for a period of 6 wk with two regimens of each of the drugs (roxarsone, 45.4 or 90.8 g/ton feed; monensin, 100 or 150 g/ton feed). None of the treatments had any adverse effect on the growth of the birds or caused any significant leg problem. Roxarsone at 45.4 g/ton caused a significant gain in body weight. The biomechanical strength of digital flexoral tendons was measured in several ways. There were no statistical differences in load at break, the modulus of elasticity, or stress or strain levels between different treatment groups and birds that received no medication. There were no differences in collagen, proteoglycan, and pyridinoline content of tendons. Sequential extraction of tendons with different solvents revealed a significant increase in the percentage of guanidine HCl extractible collagens in monensin-treated birds, and a decrease in the acid extractible collagen in both roxarsone- and monensin-treated groups. The relative content of collagen in acid extractible collagens were significantly small relative to total collagen content. Majority of collagen (84 to 90%) was extractible with pepsin. About 8 to 11% of total collagen was resistant to pepsin that was extractible with collagenase; this did not differ between treatment groups. Roxarsone treatment had no effect on the guanidine soluble collagen pool. The effect of monensin on the increase in guanidine soluble pool of collagen may relate to its disruptive effects on cellular secretory processes, which may be of significance in modulating connective tissue function in conjunction with other factors. However, in the present study, neither roxarsone nor monensin alone produced any significant leg problems nor caused any significant differences in the physiology of flexoral tendons or altered their biomechanical properties.
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PMID:Effects of roxarsone and monensin on digital flexoral tendons of broiler chickens. 956 33

Phosphoprotein appears to play an important role in the mineralization of dentin during tooth development and remineralization after demineralization by dental caries. To better understand this role, we describe the extraction and characterization of phosphoprotein from immature, human root apex dentin during and after EDTA demineralization. The extraction procedure included dissociation of the demineralized dentin matrix by guanidine hydrochloride (Gdn.HCl) followed by subsequent digestion with cyanogen bromide (CNBr) and collagenase. Characterization of these extracts included 'Stains-All' staining of SDS polyacrylamide gels (SDS-PAGE) and amino acid, protein and phosphorus analyses. The ability of these matrices to remineralize was determined by TEM and measuring calcium levels in the remineralized tissue by atomic absorption spectroscopy. The staining of SDS-PAGE gels and amino acid analysis showed that an intact phosphophoryn was extracted from the dentin of the immature apices during EDTA demineralization and that it had an apparent Mr approximately 140,000. In the subsequent extracts and digests, the phosphoprotein has a range of molecular weights, some of which may have been degraded products of the intact phosphoprotein. A greater quantity of phosphoprotein was found in the EDTA-demineralized dentin matrices than in dentin after Gdn.HCl, CNBr and collagenase digests. These EDTA-demineralized matrices also remineralized to a greater extent than those dissociated with Gdn.HCl. The differences in both the quantity and the quality, as defined by the amino acid residue profile, of the phosphoprotein in the sequential extracts of the root apex dentin may be important in affecting the ability of this tissue to remineralize.
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PMID:Phosphoprotein analysis of sequential extracts of human dentin and the determination of the subsequent remineralization potential of these dentin matrices. 970 61

Diabetes mellitus in rats is characterized by excessive activity of several matrix metalloproteinases (MMPs), notably collagenase(s) and gelatinase(s), in skin, gingiva, and other tissues. A number of tetracyclines (TCs), both antimicrobial compounds as well as chemically modified non-antimicrobial TC analogues (CMTs) are known to possess potent inhibitory activity against these enzymes. Three conventional antimicrobial TCs and six CMTs were used in this study. In vitro, doxycycline was shown to possess higher inhibitory capacity (i.e. lower IC(max)) against diabetic rat skin collagenase than either minocycline or tetracycline HCl. Addition of excess zinc partially reversed the proteinase inhibition by TCs. In vivo, using rats made diabetic with streptozotocin (STZ), oral administration of various TCs led to decreased weight loss and substantial reductions in the activity of both skin collagenase and skin gelatinase (primarily MMP-9, 92 kDa) without affecting blood glucose. Using an in vitro spectrophotometric technique, the Zn(++) reactivity of several CMTs was assessed and found to be positively related to the potency of these compounds as MMP inhibitors. One particular CMT (CMT-5, pyrazole analogue), which is neither antimicrobial nor capable of binding metal cations, did not inhibit the MMPs. TCs have potential utility in management of diabetic complications mediated by excessive activity of MMPs.
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PMID:Excessive matrix metalloproteinase activity in diabetes: inhibition by tetracycline analogues with zinc reactivity. 1117 85

Recent studies indicate that 1alpha,25-dihydroxyvitamin D3 (1alpha,25[OH]2D3) and 24R,25-dihydroxyvitamim D3 (24R,25[OH]2D3) differentially regulate proliferation, differentiation, and matrix synthesis of growth plate chondrocytes. To determine whether both metabolites play the same or different roles in vivo, we used the vitamin D-deficient rat as a model. Rickets was induced and then reversed by administering a single dose of ergocalciferol, 1alpha,25(OH)2D3, or 24R,25(OH)2D3 and euthanizing the animals after 4, 24, 48, or 72 h. Growth plates were either processed for histology and histomorphometry or extracted with buffered guanidine-HCl. Neutral metalloproteinase activity in the extracts was measured by use of aggrecan-containing beads, and collagenase activity was determined by use of radioactive type I collagen. The levels of tissue inhibitor of metalloproteinases (TIMP) and plasminogen activator were also determined. The morphology of the growth plate varied as a function of treatment. While 24R,25(OH)2D3 appeared to affect cell maturation and 1alpha,25(OH)2D3 appeared to affect terminal differentiation and calcification, response to ergocalciferol was indicative of the combined responses to the individual metabolites. Enzyme activity was regulated in a differential manner. Treatment with ergocalciferol produced a rapid decline in both neutral metalloproteinase and collagenase activities that was statistically significant by 4 h. By contrast, 1alpha,25(OH)2D3 had no effect on neutral metalloproteinase activity but caused a significant decrease in both active and total collagenase activity by 4 h, while 24R,25(OH)2D3 decreased neutral metalloproteinase activity by 48 h and had no effect on collagenase activity. Ergocalciferol had no effect on TIMP levels at any time examined, whereas 1alpha,25(OH)2D3 caused an increase at 48 and 72 h and 24R,25(OH)2D3 completely blocked TIMP production at 4 and 24 h. By contrast, plasminogen activator activity by ergocalciferol was decreased at 4 h, increased by 1alpha,25(OH)2D3 at 4 and 24 h, and decreased by 24R,25(OH)2D3 at all time points examined. These in vivo results confirm our previous cell culture observations showing that growth plate chondrocytes are differentially regulated by 1alpha,25(OH)2D3 and 24R,25(OH)2D3. Moreover, they show definitively that these two vitamin D metabolites play distinct roles not only in regulating neutral metalloproteinase and collagenase activities in growth plate cartilage but in cell maturation and calcification of this tissue in vivo.
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PMID:Effect of 1alpha,25-dihydroxyvitamin D3 and 24R,25-dihydroxyvitamin D3 on metalloproteinase activity and cell maturation in growth plate cartilage in vivo. 1144 27

We investigated the role of polymorphonuclear neutrophil (PMN) proteinases, elastase, and gelatinase B in rat models of acute lung injury. Three groups of rats were studied 6 hours after unilateral instillation of hydrochloric acid (HCl; 0.1 N), lipopolysaccharide (LPS) (4 microg), or saline. The results demonstrated that HCl-induced lung injury, as compared with LPS-induced lung injury, was associated with an increase in permeability (wet/dry weight ratio and proteins in bronchoalveolar lavage fluid). In contrast, there was similar PMN recruitment (in bronchoalveolar lavage fluid and myeloperoxidase activity in lung homogenates) and similar proteinase exocytosis (residual alveolar PMN content of elastase and gelatinase B) in both types of lung injury. In situ zymography, evaluating interstitial protease/inhibitor balance, demonstrated a decrease in gelatinolytic activity in both HCl- and LPS-injured lungs compared with normal lung. The increase in interleukin 6 concentration in lung homogenates, which is observed after both injuries compared with saline-instilled animals, could be involved in up-regulation of tissue inhibitor of matrix metalloproteinase-1, shown by immunocytochemistry to participate in antiproteinase excess. Neither inhibition of alveolar neutrophil influx using a leukocyte elastase inhibitor (EPI-hNE-4) nor inhibition of gelatinase activities by recombinant adenovirus for the human tissue inhibitor of matrix metalloproteinase 1 gene transfer decreased lung edema in HCl-induced injury. These data suggest that PMN proteinases do not contribute to HCl-induced acute lung injury in rats.
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PMID:Neutrophil proteinases in hydrochloric acid- and endotoxin-induced acute lung injury: evaluation of interstitial protease activity by in situ zymography. 1185 May 27

Nowadays, bone tissue employed to manufacture screws used as osteosynthesis material is obtained from organ donors. But in different medical fields there is an increasing need to use xenogenic grafts and implants, which still imply risks of transmission of some diseases and antigenicity. Two different autoclaving programs (A1, A2) and an alternative to reduce the antigenicity of screws made of xenogenic bone based on enzymatic treatment are analyzed from a biomechanical point of view. 128 screws made of bovine femur bone were employed. Some of them were partially demineralized with 0.6 N HCl, enzymatically digested with collagenase (specific) and pepsin (nonspecific) and then autoclaved. The specimens were subjected to tension, shear and screw torque tests and histologically evaluated. Compared to A1, A2 sterilization method (134 degrees C but higher vacuum and longer time) considerably reduced the mechanical strength of specimens. The enzymatic digestion, expected to reduce antigenicity, did not affect the screw superficial structure and would not modify the bone biomechanical properties per se, but maybe because of the association with autoclaving and partial demineralization.
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PMID:Effects of enzymatic treatments on the biomechanical properties of screws made of bone. 1261 85

Although sarpogrelate HCl is widely used for the prevention of arterial thrombosis, its effect on atherosclerosis is unknown. Accordingly, we here investigated the effects of sarpogrelate HCl on a rabbit model of atherosclerosis. Male rabbits were fed a 0.5% cholesterol diet (HCD) (Gp 1), HCD with vitamin E (Gp 2), HCD with vitamin E and sarpogrelate (Gp 3), or HCD with sarpogrelate alone (Gp 4) for 8 weeks. The atherosclerotic area was decreased by feeding of vitamin E and sarpogrelate (16.9+/-2.0% in Gp 1 vs. 8.2+/-2.0% in Gp 3). Tone-related basal NO release was higher in Gps 3 and 4. Acetylcholine-induced relaxation tended to be improved in Gp 3. The amount of eNOS mRNA was increased in Gp 4, and aortic cyclic GMP concentration showed the same tendency. O(2)(-) release tended to be decreased in Gps 2 and 3. The matrix metalloproteinase-1 (MMP-1)-positive area was decreased, and the percentage ratio of cell numbers of smooth muscle cells/macrophages in the plaque was increased in Gp 3. The results demonstrated that sarpogrelate HCl retards the progression of atherosclerosis in rabbits, and that this effect is enhanced by concomitant administration of vitamin E. Although upregulation of eNOS may play a role as one of the underlying mechanisms, our results suggest that an additional mechanism-possibly involving the antiproliferative effects of sarpogrelate HCl on smooth muscle cells and macrophages-may also play an important role.
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PMID:Sarpogrelate HCl, a selective 5-HT2A antagonist, retards the progression of atherosclerosis through a novel mechanism. 1273 83

Both tension and stiffness as a function of muscle length were measured under relaxing conditions on isolated small bundles of chemically skinned myofibers from normal and dystrophic chicken pectoral muscles. It was shown that the dystrophic muscle was stiffer than normal muscle and developed more tension for the same amount of stretch. A fraction of stiffness was not removed by extraction with either 0.6 M KI or with 5 M guanidine HCl mixed with 1% mercaptoethanol. The stiffness of dystrophic muscle was also unaffected by treatment with bacterial collagenase under conditions that destroyed the stiffness of tendon. Nyquist plots of normal and dystrophic muscles during calcium-activated isometric contraction were very similar and were characteristic of fast-twitch muscle, as evidenced by three clear exponential processes. The normal appearance of the Nyquist plot of dystrophic muscle demonstrates that cross-bridge function is not altered, and the characteristic slowing of contraction and relaxation is not a consequence of a fast-to-slow transformation of muscle types. The increased stiffness of dystrophic muscle may be a very fundamental change in the biomechanics of dystrophy. We postulate that the stiffness is mediated by an altered form of collagen, which is collagenase-resistant by virtue of excessive crosslinking.
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PMID:Stiffness and contractile properties of avian normal and dystrophic muscle bundles as measured by sinusoidal length perturbations. 1675 74

Matrix metalloproteinases (MMPs) are present in sound coronal dentin and may play a role in collagen network degradation in bonded restorations. We investigated whether these enzymes can also be detected in root dentin. Crown and root sections of human teeth were powderized, and dentin proteins were extracted by using guanidine-HCl and EDTA. Extracts were analyzed by zymography and Western blotting for matrix metalloproteinases detection. Zymography revealed gelatinolytic activities in both crown and root dentin samples, corresponding to MMP-2 and MMP-9. MMP-2 was more evident in demineralized root dentin matrix, whereas MMP-9 was mostly extracted from the mineralized compartment of dentin and presented overall lower levels. Western blot analysis detected MMP-8 equally distributed in crown and root dentin. Because MMPs are also present in radicular dentin, their contribution to the degradation of resin-dentin bonds should be addressed in the development of restorative strategies for the root substrate.
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PMID:Determination of matrix metalloproteinases in human radicular dentin. 1941 83

Clostridium histolyticum collagenase is responsible for extensive tissue destruction in gas gangrene, and its activity is enhanced by calcium ions. The collagen-binding domain is the minimal segment of the enzyme required for binding to insoluble collagen fibrils and for subsequent collagenolysis. The collagen-binding domain is joined to another binding module by a conserved 14-amino-acid linker. The linker undergoes secondary structural transformation from an alpha-helix to a beta-strand and forms a nonprolyl cis-peptide in the presence of calcium ions. In this study, various biophysical methods were utilized to better understand the structure and functional role of the novel calcium-activated linker. Two Ca(2+) ions bind cooperatively with macroscopic association constants of K(1) = 5.01 x 10(5) m(-1) and K(2) = 2.28 x 10(5) m(-1). The chelation of the second calcium ion is enthalpically unfavorable, which could be a result of isomerization of the nonprolyl cis-peptide. The holo protein is more stable than the apo protein against thermal denaturation (DeltaT(m) approximately 20 degrees C) and chemical denaturation (DeltaDeltaG(H2O) approximately 3 kcal x mol(-1) for urea or guanidine HCl denaturation and Delta20% v/v in 2,2,2-trifluoroethanol). The compact holo collagen-binding domain is more resistant to proteolytic digestion than the apo collagen-binding domain. The orientation of the linker appears to play a crucial role in the stability and dynamics of the collagen-binding domain.
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PMID:Ca2+-induced linker transformation leads to a compact and rigid collagen-binding domain of Clostridium histolyticum collagenase. 1949 Jan 18


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