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)

In confluent human skin fibroblasts maintained in 0.5% serum-supplemented medium. L-ascorbate specifically stimulated the rate of incorporation of labeled proline into total collagenase-sensitive protein, without changing the specific activity of the intracellular free proline. This influence of ascorbate reached a maximum at 30 microM and continued for at least 4 days, resulting in a 4-fold increase. The ascorbate effect occurred in cells at both confluent and subconfluent densities and was evident at all serum concentrations from 0.5-20%. The effect was independent of duration of the radioactive pulse between 2-6 h. D-Ascorbate, D-isoascorbate, and L-dehydroascorbate also stimulated collagen synthesis but at considerably higher concentrations, i.e., 250-300 microM. The stimulation of collagen synthesis by ascorbate and its analogs was accompanied by a decline in prolyl hydroxylase activity and a rise in lysyl hydroxylase activity; again L-ascorbate was found to be most effective. Dimethyltetrahydropterine and L-lactate failed to produce these effects.
J Invest Dermatol 1983 Aug
PMID:Collagen synthesis in cultured human skin fibroblasts: effect of ascorbic acid and its analogs. 630 3

Human skin fibroblast cultures have been employed to study the effects of a variety of vitamin A analogues (retinoids) on the expression of two enzymes involved in collagen degradation in the skin, collagenase and a gelatinolytic protease. In normal and recessive dystrophic epidermolysis bullosa fibroblast cultures, retinoic acid compounds were effective inhibitors of the accumulation of both enzymes in the culture medium with half-maximal inhibitions occurring at 0.25-1 microM for collagenase and at 3-6 microM for the gelatinolytic protease. Various retinoids exhibited differing degrees of inhibitory actions, so that at a 1 microM concentration, relative inhibitions were: 13-cis-retinoic acid greater than all-trans-retinoic acid greater than aromatic retinoid (Ro 10-9359) much greater than retinol. The retinoic acid-mediated decrease in collagenase activity was accompanied by a parallel decrease in immunoreactive collagenase protein, suggesting that the retinoic acids were acting to inhibit synthesis of the enzyme. However, an additional effect of these agents was encountered. Although the retinoids themselves had no direct collagenase inhibitory action, medium derived from cultures maintained in these retinoids showed direct inhibitory capacity which was dependent both on the concentration of retinoic acid and on the length of time in culture. The results suggest that the retinoic acids modulate collagenase in vitro by two mechanisms: by decreasing the synthesis of enzyme protein and by modulating the expression of an inhibitory molecule.
J Invest Dermatol 1983 Aug
PMID:Retinoic acid inhibition of collagenase and gelatinase expression in human skin fibroblast cultures. Evidence for a dual mechanism. 630 4

We have investigated potential mechanisms for blister formation by assaying proteolytic enzymes in the blister fluids of patients with various bullous diseases. Blister fluids were obtained from patients with dermatitis herpetiformis (DH), bullous pemphigoid (BP), chronic bullous disease of childhood (CBDC), and pemphigus vulgaris (PV). The cells were recovered by centrifugation, and the supernatants as well as the cell pellets were assayed first for collagenase activity using [3H]proline-labeled type I collagen as substrate. Collagenase activity could be detected in most cases with DH, BP, and CBDC, while no activity was found in 2 cases of PV or in 5 control blister fluids obtained from suction blisters induced in healthy control subjects. Elastase activity was assayed in the same blister fluids by using a synthetic substrate succinyl-(L-alanyl)3-paranitroanilide or soluble [14C]valine-labeled tropoelastin. High levels of elastase activity were present in all DH patients, while lower, but clearly detectable, levels were found in BP, CBDC, and PV. The enzyme activity in BP was inhibited by Na2EDTA, but not by phenylmethylsulfonyl fluoride (PMSF), and Ca2+ stimulated the activity, suggesting that the enzyme in BP was a metalloproteinase. In cell-free supernatants of the DH blister fluids, the elastase activity was markedly decreased by PMSF, indicating that most of the enzyme activity was due to a serine protease. The cells recovered from DH blister fluids also contained high levels of elastase activity which could be inhibited by PMSF but not by Na2EDTA. Thus, in DH, the elastase activity is probably derived from polymorphonuclear leukocytes abundantly present in the lesions. The results indicate that active proteases are present in the blister fluids of skin diseases, and they may play a mechanistic role in the blister formation by degrading connective tissue components of the dermis and the dermal-epidermal junction.
J Invest Dermatol 1983 Sep
PMID:Demonstration of collagenase and elastase activities in the blister fluids from bullous skin diseases. Comparison between dermatitis herpetiformis and bullous pemphigoid. 630 88

The collagenase activity in skin fibroblast cultures from three patients with rare forms of epidermolysis bullosa was assayed before and after proteolytic activation of the medium. Two of the patients had the recessive dystrophic form of the disease (REBD), which is generally associated with abnormal collagenase activity. The other patient had an atrophic mitis form of the disease (REBA), which has not previously been associated with defective collagen metabolism. However, a similar increase in collagenase activity was found in all three cases. The total collagen production of EB fibroblasts was also enhanced, being two to five times that of control cell lines, and the intracellular hydroxylases of collagen biosynthesis were higher in the case of two EB-cell lines. These changes reflect the compensatory increase in collagen synthesis which follows the increased degradation caused by excessive free collagenase activity. Diphenylhydantoin treatment of one REBD patient for 9 months improved her condition.
Br J Dermatol 1984 Feb
PMID:Collagen metabolism in two rare forms of epidermolysis bullosa. 632 Aug 58

Melanocytes isolated from normal adult human skin were cultured in vitro. Separation of the epidermis from the dermis by trypsin flotation proved better than collagenase treatment for providing viable cultures of melanocytes with a minimum of fibroblast contamination. Centrifugation on a discontinuous, rather than a continuous Percoll gradient, was more efficient in separating the epidermal cell types. Most of the melanocytes were usually found in one particular layer, and most of the viable keratinocytes were in the sediment. None of the layers produced a uniformly high percentage of melanocytes on routine culture, but enriched melanocyte cultures could be obtained by seeding the epidermal cells in magnesium- and calcium-free medium for 24 to 48 hours, and then transferring them to fibroblast-conditioned medium containing horse serum and polyamines. Melanocytes were identified by their dendritic morphology, ultrastructure, reaction to cholera toxin and pigment production after treatment with melanocyte stimulating hormone. Pure cultures of melanocytes have been cultivated by this method for more than 43 weeks (ten passages).
Br J Dermatol 1984 May
PMID:Culture of normal adult human melanocytes. 632 93

The basement membrane zone (BMZ) of human skin is a complex structure which contains several well-defined components including bullous pemphigoid antigen, laminin, type IV collagen, and proteoglycan. Characterization of additional basement membrane (BM) constituents has been limited by their relative inaccessibility, insolubility, and low tissue concentration. We have produced a murine monoclonal antibody that has enabled us to define a unique constituent of the BMZ of human stratified squamous epithelia. The monoclonal antibody (KF-1) was raised by standard techniques using suction blister-derived trypsinized human epidermal cells as the antigen. Indirect immunofluorescence and immunoperoxidase staining of human and rhesus monkey tissues with KF-1 produced linear BMZ staining of stratified squamous epithelia. Glandular and vascular BMs were not stained. Immunoelectron microscopic studies of normal human skin and esophagus showed specific binding of KF-1 to the lamina densa of the BMZ, a localization identical to that of type IV collagen. However, unlike type IV collagen, which is not species specific and is found in all BMs, the antigen defined by KF-1 is collagenase-resistant and is specific for primate stratified squamous epithelia. These findings confirm the existence of regional variation in BM composition, and demonstrate for the first time that the lamina densa of stratified squamous epithelial BMs contains a constituent other than type IV collagen.
J Invest Dermatol 1983 May
PMID:A unique epithelial basement membrane antigen defined by a monoclonal antibody (KF-1). 634 73

A technique has been devised to isolate the thin papillary part of the dermis from punch biopsies. Papillary dermis has been treated with various proteolytic enzymes in order to release or solubilize the granular IgA deposits from the papillary dermis of patients with dermatitis herpetiformis. Incubation of the thin skin preparations with pepsin caused a disappearance of the specific fluorescence with antibodies to human IgA. After peptic digestion small amounts of IgA could be detected in the supernatants. There was some evidence that this amount was larger for preparations from patients with dermatitis herpetiformis than from controls. Corresponding procedures with trypsin, collagenase, or elastase had no detectable effect on the IgA deposits. The experiments with elastase seemed to give support for previous reports on association between the granular IgA deposits and the microfibrils of elastic fibers.
J Invest Dermatol 1984 May
PMID:Dermatitis herpetiformis: preparation of papillary dermis and the effect of proteolytic enzymes on the IgA deposits. 639 32

D-penicillamine and sodium salicylate were equally effective in suppressing the proliferation of fibroblasts from normal and scleroderma skin and rheumatoid synovial cells. The effects were concentration-dependent, beginning at around 100 microgram/ml, and proliferation was almost halted at 1600 microgram/ml. Individual cell strains of each type showed differences in drug susceptibility but there was no consistent difference between cells from normal and abnormal tissues. Acid mucopolysaccharide secretion was more clearly inhibited in scleroderma fibroblasts than in synovial cells, and penicillamine produced greater inhibition than salicylate, beginning at 10 microgram/ml and reaching almost 50% at 500 microgram/ml. Confluent cultures of scleroderma fibroblasts showed 23% less incorporation of 3H-proline into collagenase-sensitive protein in the presence of 1600 microgram/ml penicillamine, without significant effect on other protein synthesis; sodium salicylate had no effect. These data suggest that D-penicillamine may affect connective tissue metabolism in other ways than by interfering with collagen synthesis or cross-linking.
J Invest Dermatol 1980 Jun
PMID:Changes in the growth and metabolism of cells cultured from normal, sclerotic and rheumatoid connective tissue brought about by D-penicillamine and by sodium salicylate. 644 22

Several years ago the therapeutic possibilities for the treatment of inherited skin disorders were rather restricted; recently new possibilities have been developed and successfully applied. The author discusses the indications for a surgical procedure in basal cell nevus syndrome and the satisfying results revealed by dermabrasion in sebaceous adenoma of Pringle. The use of a low phenylalanine and tyrosine diet in case of palmoplantar keratosis with tyrosinemia is of theoretical as well as practical interest. However, a most striking therapeutic success is obtained by the treatment with drugs. The substitution of zinc in acrodermatitis enteropathica is very effective and not expensive! The positive effect of phenytoin in epidermolysis bullosa cicatricans is based on the partial inhibition of collagenase activity by this drug. Finally the author discusses the advantages of a treatment with retinoids in different hereditary keratinization disorders.
Ann Dermatol Venereol 1983
PMID:[Therapeutic possibilities of hereditary diseases in dermatology]. 666 38

Recent biochemical and immunohistochemical studies have described several components of basement membranes including heparan sulfate proteoglycan, 2 high molecular weight glycoproteins (fibronectin and laminin), and 2 collagen types (IV and V). These collagens have several properties which distinguish them from other types that are located in the interstitium: (a) type IV forms an amorphous, felt-like matrix, and neither IV nor V is found in large, cross-banded fibrils, (b) both have an increased content of hydrophobic amino acids, (c) the precursor (pro) forms are larger than those of interstitial collagens, (d) type IV contains interruptions within the triple helix, and e) both IV and V are resistant to human skin collagenase but are substrates for selected neutral proteases derived from mast cells, macrophages, and granulocytes. By immunofluorescence staining, type IV collagen has been localized to basement membranes at the dermal-epidermal junction, in capillaries, and beneath endothelial cells in larger vessels. Ultrastructurally it has been shown to be a specific component of the lamina densa. Type V collagen has been localized to the pericellular matrices of several cells types and may be specific for extramembranous structures which are closely associated with basal laminae. Other collagenous proteins have been described which may be associated with the extracellular matrix. One of these is secreted by endothelial cells in culture and by peptide mapping represents a novel collagen type. It is secreted under ascorbate-free conditions and is highly sensitive to proteolytic degradation. It has been proposed that a dynamic reciprocity exists between cells and their extracellular matrix which partially determines cell shape, biosynthesis, migration, and attachment. Examples of phenotypic modulation in several of these phenomena have been shown with endothelial cells grown on different substrates and isolated from different vascular environments.
J Invest Dermatol 1982 Jul
PMID:Collagens of basement membranes. 704 45


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