Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.4.21.4 (trypsin)
42,187 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

To characterize angiogenic factors produced by ovine corpora lutea (CL) during early pregnancy, two experiments were performed. In Experiment 1, luteal explants from days 12, 18, 24, and 30 (n=4 ewes/day) after mating were incubated in serum-free medium for 6 h. Luteal-conditioned media (LCM) were evaluated for their ability to stimulate proliferation of endothelial and 3T3 cells, as well as migration of endothelial cells. Pools of the LCM (one pool/day) then were characterized biochemically. In Experiment 2, two pools of LCM from days 24 of pregnancy were evaluated for their effects on endothelial cell, 3T3 cell, and ovine luteal cell proliferation. These pools of LCM then were concentrated by ultrafiltration and subjected to heparin-agarose affinity chromatography with salt gradient (0-4 M NaCl in buffer) elution, and fractions were evaluated for mitogenic activity for endothelial and 3T3 cells. The resulting five peaks of mitogenic activity from heparin-agarose chromatography were characterized biochemically. The five peaks of mitogenic activity were further purified by using chromatography, then were concentrated and subjected to SDS-PAGE and Western analysis for FGF-2. Ovine CL from each day of early pregnancy secreted mitogens (P<0.05) for endothelial (285 +/- 8% of unconditioned media controls) and 3T3 (142 +/- 7%) cells as well as factors which stimulated migration of endothelial cell (153 +/- 8% of controls). LCM pool from day 24 of pregnancy also stimulated (P<0.05) proliferation of ovine luteal cells in a dose-dependent manner. In Experiment 1, mitogenic activity for endothelial cells was greater than 100 kDa, heat-labile, trypsin-sensitive and bound to DEAE-Sephacel and heparin-agarose columns, but not to a CM-Sepharose column. Antibody against FGF-1 did not affect mitogenic activity of LCM for endothelial and 3T3 cells, whereas treatment with FGF-2 antibody decreased (P<0.05) mitogenic activity of LCM for both endothelial and 3T3 cells. In Experiment 2, heparin-agarose affinity chromatography resolved five peaks of mitogenic activity: a non-heparin-binding peak that was specific for 3T3 cells, three heparin-binding peaks that were specific for endothelial cells, and one heparin-binding peak that was specific for 3T3 cells. In Experiment 2, heparin-, heat-, or trypsin-treatment and immunoneutralization with FGF-1 or FGF-2 antibodies influenced mitogenic activity of all of the peaks. Whereas SDS-PAGE demonstrated several bands of protein within each peak, Western analysis was unable to detect the presence of FGF-2 in any of the heparin-binding peaks. These data demonstrate that ovine CL from early pregnancy produce mitogenic factors that can be resolved into 5 separate peaks of activity with differing affinities for heparin. These data also indicate that the endothelial mitogens produced by CL of early pregnancy are immunologically related to, but biochemically distinct from FGF-2. Mitogens for endothelial and other cells likely play a role in regulation of luteal function during early pregnancy in sheep.
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PMID:Initial characterization of mitogenic activity of ovine corpora lutea from early pregnancy. 867 47

A new tissue repair agent, RGTA11, is described for its ability to enhance colonic anastomosis repair and resistance to leakage. RGTA11 is a dextran derivative containing 110% carboxymethyl groups, 2.6% carboxymethyl benzylamide groups, and 36.6% carboxymethyl benzylamide sulfonate groups. RGTA11 was deemed efficient to protect the heparin-binding growth factors FGF2 against trypsin digestion. By this property RGTA11 mimicked heparin or heparan sulfate. We have also found that RGTA11 protected TGF beta 1 against trypsin digestion while heparin did not. RGTA11 was then tested in an in vivo wound-healing model of colonic anastomosis. Our results indicate that after 48 h, RGTA11- or RGTA11/FGF-2-treated animals presented a resistance of the anastomosis to leakage which was increased twofold (p < 0.05) over untreated controls. After 96 h and until day 7 there was no more difference with control animals. Our results suggest that RGTA11 presents potential clinical interest by preventing earlier leakage of colonic anastomosis.
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PMID:Heparin-like polymers derived from dextran enhance colonic anastomosis resistance to leakage. 880 53

Several derivatized dextrans (DxD) containing defined percentage of carboxymethyl, carboxymethyl benzylamide and carboxymethyl benzylamide sulfonate groups have been shown to stimulate tissue repair in various in vivo models including skin, bone, muscle and cornea. These selected DxD were also shown to mimic heparin or heparan sulfate by their ability to interact with, stabilise and protect the heparin-binding growth factor of the fibroblast growth factor family against trypsin digestion (Tardieu et al., J. Cell. Physiol. 1992; 150: 94). The wound healing action of these DxD was explained by postulating that the endogenously released heparin-binding growth factors could be protected within the wound. To further understand the action of these DxD on tissue repair, we have studied their effect on the human neutrophil elastase (HNE) activity, one of the proteases involved in wound repair. These DxD inhibited HNE in an hyperbolic non-competitive manner. Extent of HNE inhibition by DxD increased with their molecular weight and benzylamide sulfonate substitution levels. One DxD, RGT11, was the best inhibitor (Ki 40 pM) and efficiently inhibited FGF-2 proteolysis by HNE, restoring its growth-promoting activity towards human skin fibroblasts. The data contribute to a better understanding of the wound-healing property and anti-inflammatory activity of these polymers.
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PMID:FGF protection and inhibition of human neutrophil elastase by carboxymethyl benzylamide sulfonate dextran derivatives. 885 63

Heparin and related molecules have been identified as important participants in fibroblast growth factor (FGF) signaling although the mechanisms of action remain unclear. We have used heparin oligosaccharides to examine steps in the signaling process which could be affected by the polysaccharide. Immobilized FGF-1 and FGF-2 bound all sizes of oligosaccharides tested, ranging from tetrasaccharide to decasaccharide, at physiological salt concentration. Each group of oligosaccharide was eluted from the FGF affinity columns in several peaks, and larger oligosaccharides showed higher apparent affinity for the immobilized growth factors compared to the shorter ones. Heparin hexasaccharides were the smallest fragments providing complete protection of FGF-1 and FGF-2 against trypsin digestion. Tetrasaccharides, however, were able to provide partial protection. The requirement of heparin for ligand-receptor interaction was evaluated in receptor binding assays using Sf9 insect cells engineered to overexpress different recombinant FGF receptor (FGFR) species including FGFR1 beta, FGFR1 alpha or FGFR4 at the cell surface. In these assays hexasaccharides were the smallest fragments capable of stimulating FGF-receptor interaction. Over the range of concentrations examined, neither hexasaccharides nor octasaccharides were able to stimulate receptor binding to the level attained by intact heparin. In fact, these oligosaccharides interfered with the ability of intact heparin in promoting FGF-receptor binding. The presence of both stimulatory and inhibitory activities in hexasaccharide and octasaccharide populations could be attributed to structural heterogeneity within the oligosaccharide preparations. However, similar observations were obtained with "highly-sulfated" structurally homogeneous preparations of hexasaccharide and octasaccharide, although these molecules generally had greater stimulatory and less inhibitory activity than their structurally heterogeneous counterparts. Hexasaccharides were found to be the smallest fragments able to potentiate the FGF-1-induced 3T3 cell proliferation while their effect on FGF-2 signaling was less clear. These observations suggest that heparin can modulate FGF-signaling at several stages with different end results.
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PMID:Heparin-dependent fibroblast growth factor activities: effects of defined heparin oligosaccharides. 917 73

We have examined the importance of cell surface heparan sulfate proteoglycans (HSPG) in fibroblast growth factor (FGF) signaling. 3T3 cells grown under conventional conditions were much more sensitive to FGF-2 compared to FGF-1. However, cells were equally sensitive to FGF-1 and FGF-2 using conditions which reduced the effect of endogenous HSPG. Addition of heparin, or treatment with chlorate, an inhibitor of proteoglycan sulfation, resulted in enhanced or reduced growth factor response, respectively, and eliminated the differences between FGF-1 and FGF-2. HSPGs isolated from trypsin digests of 3T3 cells had a much higher affinity for FGF-2 compared to that for FGF-1 when analyzed by affinity chromatography. Glycosaminoglycan chains or core protein fragments derived from the HSPG failed to show the same high apparent affinity for FGF-2, suggesting that an intact proteoglycan structure was important for the high FGF-2 affinity. Addition of HSPG ectodomains, isolated from cultured 3T3 cells or produced as recombinant molecules, to chlorate-treated cultures of 3T3 cells inhibited the mitogenic activity of FGF-2 and eliminated the effect of heparin as a potentiator of either growth factor. These results support the idea that the cell-associated HSPG is an integral component of the FGF signaling system and in 3T3 cells contributes to the increased sensitivity of these cells to FGF-2 compared to FGF-1. Since isolated ectodomains of HSPG inhibited rather than stimulated the mitogenic response of the FGFs, the proper anchoring of the HSPG in the cell membrane appears to be important for a stimulatory effect.
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PMID:Is the sensitivity of cells for FGF-1 and FGF-2 regulated by cell surface heparan sulfate proteoglycans? 920 30

Mast cells are traditionally viewed as effector cells of immediate type hypersensitivity reactions. There is, however, a growing body of evidence that the cells might play an important role in the maintenance of tissue homeostasis and repair. We here present our own data and those from the literature elucidating the possible role of mast cells during wound healing. Studies on the fate of mast cells in scars of varying ages suggest that these cells degranulate during wounding, with a marked decrease of chymase-positive cells, although the total number of cells does not decrease, based on SCF-receptor staining. Mast cells contain a plethora of preformed mediators like heparin, histamine, tryptase, chymase, VEGF and TNF-alpha which, on release during the initial stages of wound healing, affect bleeding and subsequent coagulation and acute inflammation. Various additional vasoactive and chemotactic, rapidly generated mediators (C3a, C5a, LTB4, LTC4, PAF) will contribute to these processes, whereas mast cell-derived proinflammatory and growth promoting peptide mediators (VEGF, FGF-2, PDGF, TGF-beta, NGF, IL-4, IL-8) contribute to neoangiogenesis, fibrinogenesis or re-epithelization during the repair process. The increasing number of tryptase-positive mast cells in older scars suggest that these cells continue to be exposed to specific chemotactic, growth- and differentiation-promoting factors throughout the process of tissue remodelling. All these data indicate that mast cells contribute in a major way to wound healing. their role as potential initiators of or as contributors to this process, compared to other cell types, will however have to be further elucidated.
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PMID:Mast cells and their mediators in cutaneous wound healing--active participants or innocent bystanders? 1020 16

Sulfated beta-(1-->4)-galacto-oligosaccharides were prepared from an arabino-galacto-rhamno-galacturonan from Lupinus polyphyllus Lindl. by successive partial hydrolysis and SO3-pyridine sulfation in DMF. The resulting oligosaccharide polysulfates were analyzed by analytical GPC and the sulfate content was determined by ion chromatography. DP 5 and higher showed a pronounced antiangiogenic effect with scores of 0.9-1.2 for DP 7-9 using the CAM-assay. An interaction with the fibroblast growth factor FGF-2 was noticed for DP 4-12 depending on the degree of sulfation using the FGF-2-trypsin assay.
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PMID:Sulfated beta-(1-->4)-galacto-oligosaccharides and their effect on angiogenesis. 1127 Aug 23

LaPSvS1, a highly sulfated branched (1-->3)-beta-galactan was prepared from the arabino-galactan from Larix decidua Miller by partial hydrolysis and subsequent sulfation with SO(3)-pyridine in DMF. The molecular weight was analyzed by GPC and the sulfate content was determined by ion chromatography. LaPSvS1 exhibited good antiangiogenic and antiinflammatory effects in two different modifications of the known CAM-assay. In vitro results obtained in the FGF-2-trypsin-assay and in fluorospectrometric experiments revealed that LaPSvS1 interacts with the fibroblast growth factor 2 system. This interaction is correlated with the in vivo effect of LaPSvS1 on FGF-2 induced angiogenesis.
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PMID:LaPSvS1, a (1-->3)-beta-galactan sulfate and its effect on angiogenesis in vivo and in vitro. 1220 7

TTSPs [type II TMPRSSs (transmembrane serine proteases)] are a growing family of trypsin-like enzymes with, in some cases, restricted tissue distribution. To investigate the expression of TTSPs in the nervous system, we performed a PCR-based screening approach with P10 (postnatal day 10) mouse spinal cord mRNA. We detected the expression of five known TTSPs and identified a novel TTSP, which we designated neurobin. Neurobin consists of 431 amino acids. In the extracellular part, neurobin contains a single SEA (sea-urchin sperm protein, enterokinase and agrin) domain and a C-terminal serine protease domain. RT-PCR (reverse transcription-PCR) analysis indicated the expression of neurobin in spinal cord and cerebellum. Histochemical analysis of brain sections revealed distinct staining of Purkinje neurons of the cerebellum. Transiently overexpressed neurobin was autocatalytically processed and inserted into the plasma membrane. Autocatalytic activation could be suppressed by mutating Ser(381) in the catalytic pocket to an alanine residue. The protease domain of neurobin, produced in Escherichia coli and refolded from inclusion bodies, cleaved chromogenic peptides with an arginine residue in position P(1). Serine protease inhibitors effectively suppressed the proteolytic activity of recombinant neurobin. Ca2+ or Na+ ions did not significantly modulate the catalytic activity of the protease. Recombinant neurobin processed 17-kDa FGF-2 (fibroblast growth factor-2) at several P(1) lysine and arginine positions to distinct fragments, in a heparin-inhibitable manner, but did not cleave FGF-7, laminin or fibronectin. These results indicate that neurobin is an authentic TTSP with trypsin-like activity and is able to process FGF-2 in vitro.
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PMID:Neurobin/TMPRSS11c, a novel type II transmembrane serine protease that cleaves fibroblast growth factor-2 in vitro. 1821 25

Novel chitosan (CHS) and cellulose sulfates (CSs) are studied regarding their mitogenic activity and their protective effect against proteolytic digestion of FGF-2. An intermediate degree of sulfation (DS(S) ) and lower concentration of CHS have superior effect on 3T3 cell growth while the mitogenic activity of CS increases with DS(S) and concentration. Experiments with trypsin as model proteinase show that protection of FGF-2 from proteolytic digestion depends on DS(S) and the concentration of derivatives in the same manner as cell growth. Studies on stability of FGF-2 added to cultures of 3T3 cells show that the FGF-2 concentration remains higher in the presence of derivatives. Results indicate that the mitogenic activity of CHS and CS is due to protection of FGF-2 from proteolytic cleavage.
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PMID:Mitogenic activity of sulfated chitosan and cellulose derivatives is related to protection of FGF-2 from proteolytic cleavage. 2245 60


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