Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:1.3.5.1 (succinate dehydrogenase)
 8,177 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

In an in vitro study with rat liver, ammonium meta vanadate (NH4VO3) was found to inhibit microsomal ketamine N-demethylation, lipid peroxidation, and hydrogen peroxide formation; to have no effects on 4-methylaminoantipyrine N-demethylation and on glucuronyltransferase I activity, and to enhance glucuronyltransferase II. Mitochondrial succinate dehydrogenase and cytochrome c reductase were inhibited but cytochrome oxidase activity was enhanced by ammonium vanadate. Ammonium meta vanadate increased malate dehydrogenase activity but had no effect on glutamate, lactate, glycerophosphate, isocitrate, glucose-6-phosphate, and 6-phosphogluconate dehydrogenases.
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PMID:Action of ammonium meta vanadate on hepatic enzymes in vitro. 660 35

The morphologic and histochemical effects of 3-nitropropionic acid (NPA) were examined in cultured murine embryonal carcinoma cells. NPA caused a dose-dependent inhibition of cell proliferation of cultured murine embryonal carcinoma cells at concentrations above 1.05 mM and was lethal at 4.2 mM. Morphologic changes included gross swelling of the cells, swelling of mitochondria and accumulation of organellar debris within the cytoplasm. NPA inhibited the activity of succinate dehydrogenase but not of malate, isocitrate or glucose-6-phosphate dehydrogenases, resulting in a decrease in intracellular ATP. Although succinate dehydrogenase activity was decreased by NPA, propionic acid and its mercapto-, 2-chloro-, and 3-chloro- derivates did not affect enzyme activity. 3-Nitropropanol also inhibited succinate dehydrogenase but only at a much higher concentration than was required with NPA. The results provide evidence that cytotoxicity caused by NPA results from inhibition of succinate dehydrogenase activity leading to depression of ATP synthesis. Loss of cellular integrity is probably a direct consequence of failure of energy-dependent cell homeostatic mechanisms such as the plasma membrane Na+/K+ pump, resulting in swelling and ultimately lysis of the cell.
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PMID:3-Nitropropionic acid toxicity in cultured murine embryonal carcinoma cells. 770 53

Subcellular localization of hexokinase in the honeybee drone retina was examined following fractionation of cell homogenate using differential centrifugation. Nearly all hexokinase activity was found in the cytosolic fraction, following a similar distribution as the cytosolic enzymatic marker, phosphoglycerate kinase. The distribution of enzymatic markers of mitochondria (succinate dehydrogenase, rotenone-insensitive cytochrome c reductase, and adenylate kinase) indicated that the outer mitochondrial membrane was partly damaged, but their distributions were different from that of hexokinase. The activity of hexokinase in purified suspensions of cells was fivefold higher in glial cells than in photoreceptors. This result is consistent with the hypothesis based on quantitative 2-deoxy[3H]glucose autoradiography that only glial cells phosphorylate significant amounts of glucose to glucose-6-phosphate. The activities of alanine aminotransferase and to a lesser extent of glutamate dehydrogenase were higher in the cytosolic than in the mitochondrial fraction. This important cytosolic activity of glutamate dehydrogenase was consistent with the higher activity found in mitochondria-poor glial cells. In conclusion, this distribution of enzymes is consistent with the model of metabolic interactions between glial and photoreceptor cells in the intact bee retina.
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PMID:Cellular and subcellular localization of hexokinase, glutamate dehydrogenase, and alanine aminotransferase in the honeybee drone retina. 815 42

Physiologically, a postprandial glucose rise induces metabolic signal sequences that use several steps in common in both the pancreas and peripheral tissues but result in different events due to specialized tissue functions. Glucose transport performed by tissue-specific glucose transporters is, in general, not rate limiting. The next step is phosphorylation of glucose by cell-specific hexokinases. In the beta-cell, glucokinase (or hexokinase IV) is activated upon binding to a pore protein in the outer mitochondrial membrane at contact sites between outer and inner membranes. The same mechanism applies for hexokinase II in skeletal muscle and adipose tissue. The activation of hexokinases depends on a contact site-specific structure of the pore, which is voltage-dependent and influenced by the electric potential of the inner mitochondrial membrane. Mitochondria lacking a membrane potential because of defects in the respiratory chain would thus not be able to increase the glucose-phosphorylating enzyme activity over basal state. Binding and activation of hexokinases to mitochondrial contact sites lead to an acceleration of the formation of both ADP and glucose-6-phosphate (G-6-P). ADP directly enters the mitochondrion and stimulates mitochondrial oxidative phosphorylation. G-6-P is an important intermediate of energy metabolism at the switch position between glycolysis, glycogen synthesis, and the pentose-phosphate shunt. Initiated by blood glucose elevation, mitochondrial oxidative phosphorylation is accelerated in a concerted action coupling glycolysis to mitochondrial metabolism at three different points: first, through NADH transfer to the respiratory chain complex I via the malate/aspartate shuttle; second, by providing FADH2 to complex II through the glycerol-phosphate/dihydroxy-acetone-phosphate cycle; and third, by the action of hexo(gluco)kinases providing ADP for complex V, the ATP synthetase. As cytosolic and mitochondrial isozymes of creatine kinase (CK) are observed in insulinoma cells, the phosphocreatine (CrP) shuttle, working in brain and muscle, may also be involved in signaling glucose-induced insulin secretion in beta-cells. An interplay between the plasma membrane-bound CK and the mitochondrial CK could provide a mechanism to increase ATP locally at the KATP channels, coordinated to the activity of mitochondrial CrP production. Closure of the KATP channels by ATP would lead to an increase of cytosolic and, even more, mitochondrial calcium and finally to insulin secretion. Thus in beta-cells, glucose, via bound glucokinase, stimulates mitochondrial CrP synthesis. The same signaling sequence is used in the opposite direction in muscle during exercise when high ATP turnover increases the creatine level that stimulates mitochondrial ATP synthesis and glucose phosphorylation via hexokinase. Furthermore, this cytosolic/mitochondrial cross-talk is also involved in activation of muscle glycogen synthesis by glucose. The activity of mitochondrially bound hexokinase provides G-6-P and stimulates UTP production through mitochondrial nucleoside diphosphate kinase. Pathophysiologically, there are at least two genetically different forms of diabetes linked to energy metabolism: the first example is one form of maturity-onset diabetes of the young (MODY2), an autosomal dominant disorder caused by point mutations of the glucokinase gene; the second example is several forms of mitochondrial diabetes caused by point and length mutations of the mitochondrial DNA (mtDNA) that encodes several subunits of the respiratory chain complexes. Because the mtDNA is vulnerable and accumulates point and length mutations during aging, it is likely to contribute to the manifestation of some forms of NIDDM.(ABSTRACT TRUNCATED)
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PMID:Mitochondria and diabetes. Genetic, biochemical, and clinical implications of the cellular energy circuit. 854 53

Hypoxic tumor cells resist most therapies and cause tumor regrowth when their environment improves. Identifying the adaptation strategies to hypoxia would help develop better tailored cancer therapies. Ehrlich carcinomas implanted on mice were analyzed histochemically for the following enzyme activities: lactate, succinate and glucose-6-phosphate dehydrogenases, dihydrofolate reductase, purine nucleoside phosphorylase, xanthine oxidoreductase, and acid phosphatase. With the exception of xanthine oxidoreductase, which was not active in tumor cells, and of succinate dehydrogenase the activity of which was not significatively altered, all other activities were much higher in perinecrotic cells with respect to cells close to blood vessels. These data suggest the integration of metabolic paths allowing purine and lipid biosyntheses. Degradation products from the necrosis are presumed to be employed as surrogates of blood-borne nutritive substances by cells distant from the vascularization.
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PMID:Characterization of the metabolism of perinecrotic cells in solid tumors by enzyme histochemistry. 869 18

The levels of succinate, lactate, glutamate, glycerophosphate and glucose-6-phosphate dehydrogenases within the linings of keratinizing and non-keratinizing odontogenic cysts were investigated using static end-point and continuously monitored Nitroblue Tetrazolium-based histochemical methods. The use of TV image analysis for quantification of formazan final reaction products was validated by demonstrating significant relationships between the integrated absorbance at 585 nm and the amount of formazan in, and thickness of, gelatin films containing reduced tetrazolium salt (r = 1.0, p < 0.001). Absorbance readings of stained sections gave mean coefficients of variation of 1.8 +/- 0.9% between day of measurement, and of 5.65 +/- 1.32% between serial sections. End-point assays indicated that the linings of odontogenic keratocysts contained higher levels of glucose-6-phosphate dehydrogenases (p < 0.0002) and lower levels of lactate dehydrogenase (p < 0.002) than those of radicular cysts. Succinate, glutamate and glycerophosphate dehydrogenase activities were similar in both cyst types. Results from continuously monitored assays, performed for glucose-6-phosphate and succinate dehydrogenases, demonstrated linear reaction rates over the first 2.75 min of reaction. The calculated enzyme activities from continuous assays were between 1.49 and 3.49 times higher than those determined from end-point assays and confirmed that levels of glucose-6-phosphate dehydrogenase were significantly higher in the linings of odontogenic keratocysts than those of radicular cysts (p < 0.004). By contrast, succinate dehydrogenase activity was significantly higher in radicular cyst linings (p < 0.03). These results highlight the benefits of an approach to in situ determination of enzyme activity using image analysis and continuous monitoring methodologies. Overall, the high level of glucose-6-phosphate dehydrogenase found in keratocyst linings is consistent with their clinical behaviour and higher level of proliferation and synthetic activity whereas the level of lactate dehydrogenase in radicular cysts probably reflects the presence of local tissue damage within these inflammatory lesions.
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PMID:In situ determination of different dehydrogenase activity profiles in the linings of odontogenic keratocysts and radicular cysts. 873 85

The enzyme histochemical profiles of glucose-6-phosphate dehydrogenase (a marker of synthetic performance), succinate dehydrogenase (an indicator of oxidative metabolism), and NADH tetrazolium reductase (a marker of overall neuronal activity) were determined for identified white muscle motoneurons in six control and six cordotomized cels. Images were digitized and mean integrated absorbances obtained using appropriate hardware and software. For motoneurons caudal to the transection site there was a significant decrease in the mean absorbance value for NADH tetrazolium reductases which declines from 0.28 a.u. (arbitrary units) in control animals to 0.23 a.u. in cordotomized animals. However, no significant changes were detected in the activities of glucose-6-phosphate and succinate dehydrogenases. The cross-sectional area of the motoneuronal cell body was not affected by cordotomy. The decrease by around 20% in overall neuronal activity, as expressed by NADH tetrazolium reductase activity, might be expected from the decline in body motility that follows cordotomy. Changes in SDH and G6PDH activities would also be expected to follow this surgery, but none were seen, perhaps because they are compensated for by changes in neuronal metabolism that result from deafferentation.
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PMID:Changes in enzyme histochemical profiles of identified spinal motoneurons of the European eel, Anguilla anguilla, following cordotomy. 881 80

The levels of succinate dehydrogenase (SDG), lactate dehydrogenase (LDG), glucose-6-phosphate-dehydrogenase (G-6-PDG), myeloperoxydase (MPO), glycogen and cationic proteins were determined in the neutrophilic granulocytes of peripheral blood of 79 rabbits after experimental contamination by endotoxin of S. typhi. The bactericidal system of neutrophils was stimulated due to the depression of SDG, activation of LDG and G-6-PDG levels. Administration of indometacinum and chlotasolum blockaded the cyclooxygenase fermentative system of prostaglandin synthesis and thus decreased the activity of S. typhi endotoxin.
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PMID:[The metabolism and bactericidal properties of the blood neutrophilic granulocytes in experimental typhoid intoxication]. 922 Oct 62

The morphological pattern of several enzymes (succinic dehydrogenase--SDH, glucose-6-phosphate dehydrogenase--G6PDH and lactic dehydrogenase--LDH) was evaluated in normal dog eyes. Special attention was paid to the uveo-scleral tissue. Cryostatic sections of dog eye were stained with toluidine blue for the recognition of the microanatomical details or with histoenzymatic methods for SDH, G6PDH and LDH activities using sodium succinate, glucose-6-phosphate and sodium lactate as substrates respectively, nicotinamide adenine dinucleotide (NAD) as a reducing agent and sodium nitro-blue-tetrazolium as a colouring substance. A moderate positive reaction for SDH and a strong positive reaction for LDH were observed in the uveoscleral tissue, while G6PDH gave negative staining. Some considerations regarding a possible active role of these enzymatic activities to the aqueous humor outflow are suggested.
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PMID:Uveoscleral outflow in dog's eye: role of several enzymes. 1067 68

Intracerebral C6 glioma xenografts spontaneously develop centrally located necrotic regions that are bordered by densely packed neoplastic cells. Proliferative and metabolic heterogeneity in these perinecrotic regions were assessed by bromodeoxyuridine (BrdU) incorporation, by immunocytological and by histochemical analyses. The borders of necrotic regions are comprised of glioma cells that express increased levels of the type 1 glucose transporter (GLUT-1) with rare cells having incorporated BrdU. By contrast, BrdU-positive glioma cells are located immediately adjacent to GLUT-1-positive cells bordering areas of necrosis. BrdU-positive glioma cells are also scattered throughout poorly vascularized, central regions of the tumor and are present at the highly vascularized tumor periphery. GLUT-1 expression increased considerably when C6 glioma cells were grown for 48 h under either the acidotic conditions of pH 6.8 or under hypoxic conditions. The perinecrotic GLUT-1-positive glioma cells in poorly vascularized, centrally located tumor regions demonstrated a 75% reduction in glycogen content and negligible glycogenolytic capacity, when compared with normal brain white matter. Cytochrome c oxidase (COX) and lactate dehydrogenase (LDH) maintained 50% enzymatic activity compared to controls, while succinate dehydrogenase (SDH) activity was 25% of control values. Based upon these findings, a metabolic model is proposed in which GLUT-1-positive perinecrotic cells are growth arrested and predominantly rely upon non-oxidative glycolysis. It is further postulated that BrdU-positive, GLUT-1-negative glioma cells within the poorly vascularized, central tumor region convert glucose-6-phosphate to nucleotide precursors for DNA replication.
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PMID:Perinecrotic glioma proliferation and metabolic profile within an intracerebral tumor xenograft. 1471


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