Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.4.24.23 (MMP)
 4,246 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

4-(Methylmercapto)-phenol (MMP) and 4-(methylsulfinyl)-phenol (MSP) are oxidized by the soil isolate Nocardia spec. DSM 43251, which is closely related to Nocardia calcarea. The rate of degradation depends on the capability of a substrate to support growth and is strongly enhanced in the presence of a second carbon source under the conditions of cooxidation. MMP and MSP are cometabolized by hydroxylation of the benzene ring with the formation of the substituted catechol following by ring cleavage between carbon atoms 2 and 3 ("meta" fission) to give 2-hydroxy-5-methylmercapto-or-2-hydroxy-5-methylsulfinylmuconic semialdehyde. Oxidation of MMP to MSP represents a bypath of MMP-oxidation. The intermediates were identified on the basis of their physical properties. The enzymes responsible for the metabolism of MMP and MSP are induced by growth with MMP or MSP, but not with glucose. MMP-and MSP-induced cells catalyze the oxidation of a variety of substituted phenols. This indicates a rather low substrate specificity of the enzymes induced by MMP and MSP.
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PMID:Bacterial metabolism of substituted phenols. Oxidation of 4-(methylmercapto)-and 4-(methylsulfinyl)-phenol by Nocardia spec. DSM 43251. 90 25

The mycobacterial polysaccharides MMP (3-O-methyl-mannose-containing polysaccharide), MGLP (lipolysaccharide containing 6-O-methylglucose and glucose), and the cyclodextrins (cyclohexaamylose and cycloheptaamylose) form stoichiometric complexes with palmitoyl-CoA (Machida, Y., Bergeron, R., Flick, P., and Bloch, K. (1973) J. Biol. Chem. 248, 6246-6247). Complex formation is presumed to result from hydrophobic interactions. In order to enhance the hydrophobic character of the cyclodextrins the following derivatives have been synthesized: heptakis (2,di-O-propyl)-, heptakis (2,6-di-O-methyl)-, pentakis (6-O-methyl)-, heptakis (3-O-methyl)-, and permethylated beta-cyclo-dextrin. These compounds stimulate fatty acid synthesis catalyzed by the Mycobacterium smegmatis fatty acid synthetase, the magnitude of the effect decreasing in the order in which the alkylated cyclodextrins are listed above. MMP or MGLP are qualitatively indistinguishable from alkylated cyclodextrins both with respect to palmitoyl-CoA binding and with respect to effects on enzyme systems, suggesting that they form inclusion complexes of the same type. On the basis of model building it is postulated that MMP in solution assumes a helical conformation with a hydrophobic channel about 6 A in diameter and approximately 29 A long, dimensions appropriate for accommodating the paraffinic chain of palmitoyl-CoA in the form of an inclusion complex. Since palmitoyl-CoA binds to polysaccharide much more tightly than free palmitate it is further postulated that ionized groups of the CoA moiety of acyl CoA participate in the binding and do so by hydrogen bonding to the hydrophilic exterior of helical MMP. Palmitoyl-CoA, and to a lesser extent palmitate, affect the optical rotation of MMP and also of the alkylated cyclodextrins indicating that complex formation induces conformational changes in the polysaccharides.
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PMID:Complex formation between mycobacterial polysaccharides or cyclodextrins and palmitoyl coenzyme A. 111 1

Currently, extracellular matrix MMP has been discussed in relation to the extrusion and spontaneous regression of the herniated mass observed in lumbar disc herniation. However, the question remains as to whether degenerated protein is really the cause of this condition's pathogenesis. We confirmed immunologically by means of electron microscopy that extrusion is caused by the AGEs (advanced glycation end products)-induced cross-linking of collagen, and that spontaneous regression is due to AGE receptors on macrophages. Further, AGEs were found to be already exposed during histogenesis, suggesting a relation to apoptosis. In lumbar disc herniation and aging, glucose-derived AGEs cross-link proteins and cause vascular tissue damage.
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PMID:Effect of AGEs on human disc herniation: intervertebral disc hernia is also effected by AGEs. 1223 77

Atrioventricular (AV) septal defects resulting from aberrant endocardial cushion (EC) formation are observed at increased rates in infants of diabetic mothers. EC formation occurs via an epithelial-mesenchymal transformation (EMT), involving transformation of endocardial cells into mesenchymal cells, migration, and invasion into extracellular matrix. Here, we report that elevated glucose inhibits EMT by reducing myocardial vascular endothelial growth factor A (VEGF-A). This effect is reversed with exogenous recombinant mouse VEGF-A165, whereas addition of soluble VEGF receptor-1 blocks EMT. We show that disruption of EMT is associated with persistence of platelet endothelial cell adhesion molecule-1 (PECAM-1) and decreased matrix metalloproteinase-2 (MMP-2) expression. These findings correlate with retention of a nontransformed endocardial sheet and lack of invasion. The MMP inhibitor GM6001 blocks invasion, whereas explants from PECAM-1 deficient mice exhibit MMP-2 induction and normal EMT in high glucose. PECAM-1-negative endothelial cells are highly motile and express more MMP-2 than do PECAM-1-positive endothelial cells. During EMT, loss of PECAM-1 similarly promotes single cell motility and MMP-2 expression. Our findings suggest that high glucose-induced inhibition of AV cushion morphogenesis results from decreased myocardial VEGF-A expression and is, in part, mediated by persistent endocardial cell PECAM-1 expression and failure to up-regulate MMP-2 expression.
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PMID:Elevated glucose inhibits VEGF-A-mediated endocardial cushion formation: modulation by PECAM-1 and MMP-2. 1259 18

In the development of diabetic nephropathy, angiotensin (Ang) II is thought to exert numerous actions on the glomerulus, and especially on the mesangium. However, the role(s) played by Ang II in the glucose metabolism per se in mesangial cells remains unclear. Ang II, at least via its type 1 receptor (AT1-R)-mediated effect, phosphorylates extracellular signal regulated kinase (ERK) by transactivation of epidermal growth factor receptors (EGF-Rs) via the Ca2+ or protein kinase C (PKC) pathways. Our objective in the present study was to assess the effect of Ang II on glucose transporter 1 (GLUT1) gene expression and to clarify the involvement of EGF-R in Ang II-mediated GLUT1 mRNA expression in glomerular mesangial cells. The results showed that Ang II upregulated GLUT1 mRNA accumulation in a time- and dose-dependent manner (peaking at 12 h; approximately 3.8-fold vs. control), and this upregulation was completely inhibited by the PKC inhibitor calphostin-C. The Ang Il-induced GLUT1 expression was significantly inhibited by the EGF-R inhibitor AG1478 (approximately 80% inhibition), by inactivation of ERK by PD98059, and by pretreatment with heparin and the metalloproteinase (MMP) inhibitor batimastat. On the other hand, phorbol ester markedly upregulated GLUT1 mRNA (approximately 8.6-fold). Batimostat and AG1478 significantly reduced the phorbol ester-induced GLUT1 mRNA expression (approximately 72 and approximately 69% inhibition, respectively). In conclusion, PKC-mediated heparin-binding (HB)-EGF/EGF transactivation followed by ERK activation plays a predominant role in the induction of GLUT1 expression by Ang II.
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PMID:Regulation of glucose transporter (GLUT1) gene expression by angiotensin II in mesangial cells: involvement of HB-EGF and EGF receptor transactivation. 1266 15

Our previous report has showed that the treatment of 48 h with 22 mM glucose prevents hypoxia-induced cardiac cell death. In the present study, we investigated whether high glucose affects the mitochondrial death pathway during hypoxia, and if it does, what relates to the high glucose induced cardioprotection. Heart-derived H9c2 cells were incubated in low (5.5 mM) or high (22 mM) glucose medium for 48 h, then transferred to a normoxic or hypoxic condition. The hypoxia-induced reduction of mitochondrial redox potential, assessed by MTT assay, was inhibited in high glucose treated cells. The mitochondrial membrane potential was significantly decreased by hypoxia in low glucose treated cells, but not in high glucose treated cells. The hypoxia-induced cytoplasmic accumulation of cytochrome c, released from the mitochondria, was blocked by a treatment of high glucose. High glucose did not induce the expression of an antiapoptotic protein Bcl-2, nor did it reduce a proapoptotic protein Bax, but it did inhibit a hypoxia-induced downregulation of Bcl-2. The cellular ATP contents were not changed by the treatment of high glucose for 48 h, and the hypoxia-induced decline of intracellular ATP level was observed in high glucose treated cells and in low glucose. A glycolytic inhibitor, 2-deoxyglucose, did not reverse the high glucose induced reduction of LDH release. The elevation of [ROS](i) induced by hypoxia was inhibited in high glucose treated cells. These results suggest that high glucose induced cardioprotection may be accounted for in part by the preservation of MMP and the maintenance of a basal level of [ROS](i) during hypoxia.
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PMID:High-glucose induced protective effect against hypoxic injury is associated with maintenance of mitochondrial membrane potential. 1503 43

Enzyme-immobilized magnetic microparticles (EMMP) have been prepared for use as a microreactor in flow injection analysis (FI). The microparticles were directly injected into the FI system. Their retention occurred within the flow line by small permanent magnets located near the detector. The analytical utility of this concept was illustrated by the assay of glucose using glucose oxidase (GOx), immobilized microparticles, and amperometric detection of liberated hydrogen peroxide. The microparticles were derived from silica gel (nominal pore diameter, 15-80 nm) by impregnation with a citric acid/ethanol solution and a ferric nitrate/ethanol solution and then by calcination in a nitrogen atmosphere to produce ferrimagnetic fine particles of spinel-type iron oxide (gamma-Fe(2)O(3)) inside the pore. They were characterized by X-ray diffraction. The calibration curve of the glucose sample (2 microL injected) was linear between 2.5 x 10(-6) and 5 x 10(-4) mol/L (R = 0.9995), and the detection limit was 1.0 x 10(-6) mol/L or 0.36 ng of injected glucose (S/N = 3). The repeatability for a 5 x 10(-4) mol/L glucose solution was RSD = 1.5% (n = 6). Application to the assay of glucose in a fermentation broth is illustrated. The GOx MMP were stable and active for more than eight months when kept at 10 degrees C.
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PMID:Preparation, characterization, and application of an enzyme-immobilized magnetic microreactor for flow injection analysis. 1536 12

Exopolysaccharide (EPS) was prepared by submerged mycelial culture of a newly isolated mushroom Grifola frondosa HB0071 in a 5-l stirred-tank fermenter. This fungus produced a high concentration of biomass (24.8 gl(-1) at day 4), thereby achieving high EPS concentration (7.2 gl(-1) at day 4). EPS was proven to be a proteoglycan consisting of 85.6% carbohydrates (mostly glucose) and 7.3% proteins with a molecular weight of 1.0 x 10(6) Da. The photoprotective potential of EPS was tested in human dermal fibroblasts (HDF) exposed to ultraviolet-A (UVA) light. It was revealed that EPS had an inhibitory effect on human interstitial collagenase (matrix metalloproteinase, MMP-1) expression in UVA-irradiated HDF without any significant cytotoxicity. The treatment of UVA-irradiated HDF with EPS resulted in a dose-dependent decrease in the expression level of MMP-1 mRNA (by maximum 61.1% at an EPS concentration 250 microgml(-1)). These results suggest that EPS obtained from mycelial culture of G. frondosa HB0071 may contribute to inhibitory action in photoaging skin by reducing the MMP 1-related matrix degradation system.
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PMID:Production of exopolysaccharide from mycelial culture of Grifola frondosa and its inhibitory effect on matrix metalloproteinase-1 expression in UV-irradiated human dermal fibroblasts. 1616 20

The agonists of peroxisome proliferator-activated receptor-gamma (PPARgamma) ameliorate cardiovascular complications associated with diabetes mellitus. We tested the hypothesis that recovery from ailing to failing myocardium in diabetes by PPARgamma agonist is in part due to decreased matrix metalloproteinase-9 (MMP-9) activation and left ventricular (LV) tissue levels of homocysteine (Hcy). C57BL/6J mice were made diabetic (D) by feeding them a high-fat calorie diet. PPARgamma was activated by adding pioglitazone (Pi) to the diet. After 6 wk, mice were grouped into: normal calorie diet (N), D, N + Pi and D + Pi (n = 6 in each group). LV variables were measured by echocardiography, endothelial-myocyte (E-M) coupling was measured in cardiac rings, and MMP-9 activation was measured by zymography. Blood glucose levels were twofold higher in D mice compared with N mice. Pi decreased the levels of glucose in D mice to the levels in N mice. LV Hcy levels were 3.5 +/- 0.5 microM in N groups compared with 12.4 +/- 0.6 microM in D groups. Treatment with Pi normalized the LV levels of Hcy but had no effect on plasma levels of Hcy. In the D group, LV contraction was reduced compared with that of the N group and was ameliorated by treatment with Pi. LV wall thickness was reduced to 0.25 +/- 0.02 mm in the D group compared with 0.42 +/- 0.01 mm in the N group. LV diastolic diameter was 3.05 +/- 0.01 mm in the D group compared with 2.20 +/- 0.02 mm in the N group. LV systolic diameter was 1.19 +/- 0.02 mm in the D group and 0.59 +/- 0.01 mm in the N group. Pi normalized the LV variables in D mice. The responses to ACh and nitroprusside were attenuated in diabetic hearts, suggesting that there was E-M uncoupling in the D group compared with the N group, which was ameliorated by Pi. Plasma and LV levels of MMP-2 and -9 activities were higher in the D group than in the N group but normalized after Pi treatment. These results suggest that E-M uncoupling in the myocardium, in part, is due to increased MMP activities secondary to suppressing PPARgamma activity in high-fat, calorie-induced Type 2 diabetes mellitus.
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PMID:Pioglitazone prevents cardiac remodeling in high-fat, high-calorie-induced Type 2 diabetes mellitus. 1660 93

Our hypothesis is that impairment of peroxisome proliferator-activated receptor-gamma (PPARgamma) initiates renal dysfunction by increasing renal glomerular matrix metalloproteinase-2 (MMP-2) activity because of increased renal homocysteine (Hcy) and decreased nitric oxide (NO) levels. C57BL/6J mice were made diabetic (D) by being fed a high-fat-calorie diet, and an increase in PPARgamma activity was induced by adding pioglitazone (Pi) to the diet. Mice were grouped as follows: normal calorie diet (N), D, N+Pi, and D+Pi (n = 6/group). The glomerular filtration rate (GFR), renal artery blood flow and pressure, and plasma glucose were measured. Renal glomeruli and preglomerular arterioles were isolated. Plasma and glomerular levels of NO, Hcy, and MMP activity were measured. The contractile response to phenylephrine and the dilatation response to acetylcholine in renal arteriolar rings were measured in a tissue myobath. In N, D, N+Pi, and D+Pi groups, respectively, GFR was 9.4 +/- 1.2, 3.9 +/- 1.1, 9.2 +/- 1.6, and 8.4 +/- 1.4 microl x min(-1) x g body wt(-1). Renovascular resistance was 140 +/- 3, 367 +/- 21, 161 +/- 9, and 153 +/- 10 mmHg x ml x min(-1). Levels of Hcy were increased from 5.8 +/- 1.5 in the N to 18.0 +/- 4.0 micromol/l in the D group. Glomerular levels of MMP-2 were increased in D mice compared with N mice, and there was no change in levels of MMP-9. Treatment with Pi ameliorated glomerular levels of MMP-2 and Hcy in the D group. Renal artery ring contraction and relaxation by phenylephrine and acetylcholine, respectively, were attenuated in the D groups compared with the N groups. Results suggest that a PPARgamma agonist ameliorates preglomerular arteriole remodeling in diabetes by decreasing tissue levels of Hcy and MMP-2 activity and increasing NO.
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PMID:Pioglitazone mitigates renal glomerular vascular changes in high-fat, high-calorie-induced type 2 diabetes mellitus. 1660 49


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