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:1.3.5.1 (succinate dehydrogenase)
8,177 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Renal clear cell tubules and clear/acidophilic cell tumors were induced in male Sprague-Dawley rats by 7 weeks oral administration (stop model) of N-nitrosomorpholine (NNM) at a concentration of 12 mg/100 ml in the drinking water. Twelve, 23 and 34 weeks after withdrawal of NNM serial cryostat sections of the kidneys were histochemically analyzed for the following parameters: glucose transporter proteins (GLUT1, GLUT2), glycogen content and the activities of glycogen synthase (SYN), glycogen phosphorylase (PHO), glucose-6-phosphatase (G6Pase), glucose-6-phosphate dehydrogenase (G6PDH), hexokinase (HK), glyceraldehyde-3-phosphate dehydrogenase (GAPDH), pyruvate kinase (PK), succinate dehydrogenase (SDH), malate dehydrogenase (MDH), alkaline phosphatase (ALP), acid phosphatase (ACP) and gamma-glutamyltransferase (GGT). Clear cell (glycogenotic) tubules first appeared at 23 weeks, and clear/acidophilic cell tumors at 34 weeks after withdrawal of the carcinogen. G6Pase, ALP, GGT and GLUT2 were absent in clear cell tubules, clear/acidophilic cell tubules, and clear/acidophilic cell tumors indicating a sequential origin of all these types of lesions from the collecting duct system, in line with previous morphological findings. In comparison to the collecting duct epithelium, glycogenotic tubules demonstrated an increased activity of PHO and reduced activities of glycolytic and mitochondrial enzymes, which were accompanied by a strongly reduced expression of GLUT1. Moderately increased activities of glycolytic and mitochondrial enzymes were observed in the clear cells of clear/acidophilic cell tubules and tumors compared with those in glycogenotic tubules. They had slightly increased activities of the glycolytic enzymes GAPDH and PK compared with normal collecting duct epithelium, while most of them were nearly lacking in GLUT1. Our findings suggest that glycogen storage is not due to an increased uptake of glucose from the blood, but results from a disturbance in intracellular flux of metabolites. The development of clear cell tubules from the normal collecting duct epithelium is accompanied by a markedly decreased expression of GLUT1 along with a reduction in glycolytic and mitochondrial enzymes. This reduction of enzyme activities is replaced by an increase in enzyme activities in clear/acidophilic cell tumors indicating a fundamental shift in carbohydrate metabolism during progression from preneoplastic to neoplastic lesions.
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PMID:Sequential changes in glycogen content, expression of glucose transporters and enzymic patterns during development of clear/acidophilic cell tumors in rat kidney. 147 41

Na-coupled D-glucose transport in rabbits with cis-diamminedichloride platinum (CDDP; cisplatin) induced acute renal failure (ARF) has been studied. ARF occurred at 3 days after injection of CDDP (3 mg/kg i.v.). Na-coupled D-glucose transport into brush-border membrane vesicles (BBMV) from both outer cortex (OC) and outer medulla (OM) of ARF rabbits under zero-trans condition was decreased. Increased Km (i.e., decreased affinity of transport carrier for D-glucose) in OC and decreased Vmax (i.e., decreased number of glucose carrier) in OM were observed in CDDP-induced ARF rabbits. Decrease glucose transport was also observed under equilibrium exchange condition. Intravesicular volume of BBMV from OC and OM of ARF rabbits was decreased. In homogenate and BBMV from OC and OM of ARF rabbits, activities of gamma-glutamyl transpeptidase and alkaline phosphatase (marker enzymes of brush-border membrane) were decreased. Activities of succinate dehydrogenase, glucose-6-phosphatase, and Na-K ATPase (marker enzymes of mitochondria, endoplasmic reticulum, and basal lateral membrane, respectively) were not affected by CDDP administration. These results suggested that one of the main target sites of CDDP in kidney is brush-border membrane (BBM) along the proximal tubule, that is, not only Na-coupled D-glucose transport carrier protein but also other proteins in BBM.
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PMID:Decreased sodium dependent D-glucose transport across renal brush-border membranes in cis-diamminedichloride platinum induced acute renal failure. 156 86

A nuclear mutant of Saccharomyces cerevisiae deficient in mitochondrial fumarase has been identified through the in vitro biochemical assay of enzyme activity after visual selection due to an increased acidification ability of its colonies. Cells of the fumarase-deficient mutant fermenting glucose accumulated extracellular fumaric acid. This accumulation was observed only in growing cultures and required functional mitochondrial electron transport from succinate dehydrogenase to oxygen.
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PMID:Fumaric acid overproduction in yeast mutants deficient in fumarase. 158 56

We have examined the expression of the gene encoding the iron-protein subunit (Ip) of succinate dehydrogenase in Saccharomyces cerevisiae. The gene had been cloned by us and shown to be subject to glucose regulation (A. Lombardo, K. Carine, and I. E. Scheffler, J. Biol. Chem. 265:10419-10423, 1990). We discovered that a significant part of the regulation of the Ip mRNA levels by glucose involves the regulation of the turnover rate of this mRNA. In the presence of glucose, the half-life appears to be less than 5 min, while in glycerol medium, the half-life is greater than 60 min. The gene is also regulated transcriptionally by glucose. The upstream promoter sequence appeared to have four regulatory elements with consensus sequences shown to be responsible for the interaction with the HAP2/3/4 regulatory complex. A deletion analysis has shown that the two distal elements are redundant. These measurements were carried out by Northern (RNA) analyses of Ip mRNA transcripts as well as by assays of beta-galactosidase activity in cells carrying constructs of the Ip promoter linked to the lacZ coding sequence. These observations on the regulation of mRNA stability were also extended to the mRNA of the flavoprotein subunit of succinate dehydrogenase and in some experiments of iso-1-cytochrome c.
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PMID:Control of mRNA turnover as a mechanism of glucose repression in Saccharomyces cerevisiae. 162 Jan 7

Oxygen consumption and enzyme activity were evaluated in platelet mitochondria from 17 patients with Parkinson's disease. In comparison with age-matched controls, no consistent abnormality could be discerned in complex I, complex II-III, or complex IV oxygen consumption, or in the enzyme activity of these respiratory chain complexes. Neither chronic therapy with levodopa/carbidopa alone nor in combination with deprenyl significantly affected any measure of mitochondrial respiratory function. There was no discernible relationship between patient age or disease severity and any parameter of mitochondrial respiration. Moreover, blood lactate levels following glucose loading were not different in patients and controls. These results fail to support the occurrence of a generalized defect in any mitochondrial respiratory function in Parkinson's disease.
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PMID:Effect of aging and dopaminomimetic therapy on mitochondrial respiratory function in Parkinson's disease. 162 Jan 40

Enzyme-histochemical studies were conducted on livers of mice chronically fed griseofulvin (GF) in order to produce Mallory bodies (MBs) in hepatocytes. The development of MBs is associated with derangement of the immunohistochemically detectable intermediate filament (IF) cytoskeleton of the cytokeratin (CK) type, although no strict correlation between appearance or involution of MBs and the cytoskeletal alterations exists. Since the function of the IF cytoskeleton and the relationship of its disturbance to cell injury is unknown, the aim of the present study was to correlate the activities of several key enzymes of cellular metabolic pathways with the disturbance of the cytoskeleton architecture. For that purpose enzyme-histochemistry in combination with immunohistochemical CK-IF stainings were performed on identical sections. In GF-intoxicated mouse livers the normal topography of enzyme activities was disturbed, but no strict colocalization of enzymatic and cytoskeletal changes was found. Glucose-6-phosphatase, a microsomal enzyme involved in glucose output and gluconeogenesis, showed elevated activity in MB-free hepatocytes with diminished immunostainable CK-IF cytoskeleton refuting the concept of a disability of those cells to export glucose. It could indeed indicate that those cells without MBs are in the state of recovery. However, these cells could also resemble "hyperactive foci". Glycogen was decreased in MB-containing hepatocytes with disturbed cytoskeleton, and this feature favours the assumption of cell degeneration. On the other hand, the mitochondrial marker enzymes, i.e. succinate dehydrogenase, cytochrome-c-oxidase and 3-hydroxybutyrate dehydrogenase, remained unchanged in altered hepatocytes. Alkaline phosphatase activity at the canalicular pole of GF-intoxicated hepatocytes was elevated, indicating cholestatic features associated with this disorder. However, since altered hepatocytes did not show impairment of oxido-reductase activities, a severe impairment of bile secretion as a consequence of cell damage is unlikely. Unchanged or even increased ATPase activity of altered hepatocytes also indicated their sustained metabolic abilities. The results presented provide indirect evidence that hepatocytes with disturbed IF cytoskeleton do not significantly differ from normal cells with respect to oxidative metabolism, fatty acid synthesis and gluconeogenesis. This suggests that alterations of the IF cytoskeleton associated with GF intoxication and MB formation have no significant adverse influence on the metabolic functions of liver cells, as far as can be assessed by evaluation by enzyme-histochemical staining of several key enzymes.
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PMID:Enzyme-histochemical studies of griseofulvin-intoxicated mouse livers. 165 25

Brown adipose tissue (Na(+)-K+)-ATPase activity, in vitro glucose uptake and 2-aminoisobutyric acid uptake, as well as mitochondrial GDP-binding and succinate dehydrogenase activity were determined in order to study the relationship between these parameters in control, cold acclimated and cafeteria-fed rats. GDP-binding, (Na(+)-K+)-ATPase and glucose uptake were increased in interscapular brown adipose tissue from cold-acclimated and cafeteria-fed rats, whereas 2-aminoisobutyric acid uptake was only increased in cafeteria-fed rats. GDP-binding and (Na(+)-K+)-ATPase activity showed a high correlation coefficient suggesting a parallel modulation of both systems, which would probably share a common regulation mechanism.
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PMID:Parallel modulation of brown adipose tissue GDP-binding, substrate uptake and (Na(+)-K+)-ATPase activity in the rat. 166 Dec 74

13C nuclear magnetic resonance (NMR) spectroscopy was used to study the metabolism of [2-13C]acetate in a diploid strain of Saccharomyces cerevisiae homozygous for the spo50 mutation. This mutation results in failure to initiate sporulation and suppresses spd mutations (which cause derepressed sporulation). By analysing the pattern of 13C-labelling in glutamate it was deduced that the glyoxylate cycle is responsible for most of the acetate utilization and that there is very little tricarboxylic acid cycle activity. The labelling of alpha,alpha'-trehalose indicated that gluconeogenesis and the hexose monophosphate pathway operate in a similar way to the wild-type. The mutant strain has higher levels of succinate dehydrogenase than the wild-type. All of the physiological alterations caused by the spo50 mutation can be explained by this difference.
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PMID:13C NMR analysis of a developmental pathway mutation in Saccharomyces cerevisiae reveals a cell derepressed for succinate dehydrogenase. 167 4

Sheep under general anesthesia had their left and right latissimus dorsi muscles mobilized for paraneuroelectrode and pulse generator implantation. After a 10-day recovery period, the left-side muscles were stimulated with a gradually increasing duration and rate over 3 months. At 4 months after operation, the tendinous end of each latissimus dorsi muscle was freed from its humeral insertion and attached to a strain gauge force transducer. Both left and right latissimus dorsi muscles, from each animal, were stimulated to contract for 2 hours for the fatigue study before being isolated, trimmed, and weighed. Frozen tissue biopsies were used to determine creatine phosphate, adenosine triphosphate, lactate, and glycogen content and muscle myosine ATPase, and succinate dehydrogenase activities. The arterial diameter in the conditioned muscle was 30% larger than that of the control muscle and had a 40% higher blood flow at rest. A three- to fivefold increase in blood flow during the fatigue test was observed. The force decreased 47% for the conditioned muscle and 91% for the control muscle. The mass and cross-sectional area of conditioned and unconditioned muscles were similar. Electric conditioning increased fatigue resistant fiber content from 33% to 92%, as evidenced by myosine ATPase activity. During the early phase of the fatigue test, higher glucose uptake but significantly lower lactate production were found for the conditioned muscle. This study indicates that it is possible to produce fatigue resistant muscle with preserved force and mass. In addition to skeletal muscle fiber transformation, metabolic adaptations appear to be important factors for fatigue resistance of skeletal muscle.
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PMID:Fatigue resistant muscle with preserved force and mass for cardiac assist. 180 6

1. Isometric twitch and tetanic tensions were recorded from whole muscles and single motor units in fourth deep lumbrical muscles isolated from young adult (60 days) rats. Muscles were superfused with oxygenated Ringer solution at 25 degrees C except where stated otherwise. 2. It was confirmed that the muscle is supplied most commonly by eleven motor axons, nine via the lateral plantar nerve (LPN), and two via the sural nerve (SN). Motor units whose axons were isolated from either LPN or SN were studied. There was no difference in mean motor unit size. 3. In their unfused tetani most units showed 'sag' and some 'no sag', with no segregation between LPN and SN. 'No sag' units were always small (unit tetanic tension less than 8% whole-muscle tetanic tension), tended to be relatively slowly contracting and relaxing during an isometric twitch, and tended to have relatively low twitch:tetanus ratios. Units showing sag ranged from large to small. 4. In some motor units muscle fibres were depleted of their glycogen by repetitive stimulation at 30 degrees C in glucose-free Ringer solution, and the muscle and its unstimulated control frozen and sectioned. Neighbouring sections were stained for glycogen and for binding of two myosin-specific antibodies, one specific for slow myosin and the other for type IIA myosin. Myosin ATPase and succinic dehydrogenase histochemistry were also carried out in some muscles. 5. Serial reconstructions showed that all or virtually all extrafusal fibres in the muscle were present in a midbelly section, and that the myosin type of individual fibres did not change significantly along their length. Spindle profiles were seen frequently and in two muscles eight and twelve spindles were identified. 6. Of twenty-six motor units examined twenty contained almost exclusively muscle fibres of the recently described type IIX. All these units showed sag in their isometric tetani. 7. Six units each contained 50% or more of slow myosin-containing fibres (IIC and a few type I). The remaining fibres in these units were IIA. All these units were therefore of mixed fibre composition, and are discussed as IIC/IIA units. In whole muscles slow-myosin-containing fibres were generally distributed evenly (non-randomly) throughout the muscle cross-section. 8. Whole muscles contained on average 970 fibres (S.D. +/- 70) of which 82 (+/- 9) were slow-myosin-containing. A few muscles from older rats (3-24 months) contained very few such fibres.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Motor units of the fourth deep lumbrical muscle of the adult rat: isometric contractions and fibre type compositions. 182 26


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