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

Spectrophotometric and fluorimetric substrate couple titrations and potentiometric spectrophotometric titrations were used to determine the oxidation-reduction potentials of components showing absorbance or fluorescence at the wavelengths attributable to the flavoproteins of mitochondria fractionated using digitonin together with sonication. A pure mitoplast fraction devoid of cytochrome b5 contamination could be obtained using 230 micrograms digitonin/mg of mitochondrial protein. The digitonin-soluble fraction contained a species having Em7.4 = -123 mV and probably represents the outer membrane flavoproteins. The inner membrane-matrix fraction, treated with ultrasound, provided evidence of a flavoprotein species with redox potential (Em7.4 = -302 mV) in the matrix fraction. The -302 mV component is probably lipoamide dehydrogenase. A high redox potential species with Em7.4 = +19 mV in titrations with the succinate fumarate couple was located in the inner membrane vesicles and is probably identical with succinate dehydrogenase. The electron-transferring flavoprotein (ETF) was isolated from bovine heart mitochondria and its Em7.4 = -74 mV determined. The component in the matrix fraction with an apparent Em7.4 = -56 mV probably represents ETF, and that in the inner membrane fraction with an apparent Em7.4 = -43 mV the NADH dehydrogenase flavoprotein. A component in an apparently low concentration with Em7.4 = +30 mV was detected in the inner membrane fraction. This probably represents the ETF-dehydrogenase flavoprotein. The origin of the flavoprotein fluorescence of mitochondria and intact tissues is discussed.
 ...
PMID:Oxidation-reduction midpoint potentials of mitochondrial flavoproteins and their intramitochondrial localization. 55 61

2-Month-old male Wistar rats were given sodium tetraborate in drinking water (3 g/l). Cerebral succinate dehydrogenase activity increased after 10 and 14 weeks of exposure. Increased RNA concentration and increased acid proteinase activity in brain occurred after 14 weeks. NADPH-cytochrome c reductase activity and cytochrome b5 content decreased in the liver microsomal fraction after 10 and 14 weeks. A reduction in the cytochrome P-450 concentration was detected at 14 weeks. The results support the hypothesis that borate anion exerts its toxic action by interfering with flavin metabolism in flavoprotein-dependent pathways.
 ...
PMID:Effects of extended peroral borate ingestion on rat liver and brain. 708 88

The experiments were carried out on 60-day and 6-month old male Wistar rats within 48 h in one season of the year (autumn). Material was collected every four hours, beginning from 10:00 a.m. The present results indicate that the fluctuations of cytochrome P-450 content in liver microsomes in both age groups occurred in a 12 h rhythm with peaks at 10:00 and 22:00. Similarly, the activity fluctuations of NADPH-cytochrome c reductase showed the 12 h rhythm, with maximal values at 10:00 and 22:00, too. The cytochrome b5 content in a younger group of rats oscillated apparently in the 12 h rhythm with the maximal values at 06:00 and 18:00. The activity course of cytochrome b5 in 6-month-old rats revealed a 24 h rhythm and two maxima of the activity were found: the first one at 14:00 and the second one at 02:00. NADH-cytochrome b5 reductase in both age groups showed a 24 h rhythm, also the activity fluctuations of succinic dehydrogenase showed a tendency to 24-h rhythmicity, and the differences between minimal and maximal values were statistically insignificant. The results of our experiment have shown some correlations between the activity of microsomal system of mixed-function oxidases and mitochondrial respiratory enzyme.
 ...
PMID:Circadian variation of mitochondrial succinic dehydrogenase and microsomal cytochrome P-450 dependent monooxygenase activity in the liver of sexually immature and mature rats. 851 25

The study aimed to evaluate the effect of age on the activity of the cytochrome P450-dependent monooxygenase system and on cellular respiration processes in Wistar rats aged 0.5, 1, 2, 4, 8, 12, 20, and 28 months. The following parameters were determined: cytochrome P450 content, cytochrome b5 content, NADPH-cytochrome P450 reductase activity, and NADH-cytochrome b5 reductase activity, succinate dehydrogenase (SDH) activity, and lactate dehydrogenase (LDH) activity. In the study, cytochrome P450 content increased in the first month of life, which was accompanied by increases in SDH and LDH activities. In the subsequent months, SDH activity decreased, whereas LDH activity increased to reach the maximum in month eight and then decreased. Cytochrome b5 content showed a decreasing tendency throughout the experiment. NADH-cytochrome b5 reductase activity showed only slight deviations in individual age groups.
 ...
PMID:Ontogenesis of hepatocyte respiration processes in relation to rat liver cytochrome P450-dependent monooxygenase system. 986 30

Piperine is a major component of black (Piper nigrum Linn) and long pepper (Piper longum Linn) used widely in various systems of traditional medicine. We have evaluated the effect of piperine on mitochondrial tricarboxylic acid cycle and phase I and glutathione-metabolizing enzymes in Benzo(a)pyrene induced experimental lung carcinogenesis in swiss albino mice. Lung cancer bearing mice showed a significant decrease in the activities of mitochondrial enzymes-isocitrate dehydrogenase (ICDH), -ketoglutarate dehydrogenase (KDH), succinate dehydrogenase (SDH), malate dehydrogenase (MDH) and significantly increased NADPH-Cytochorome reductase (NADPH-C reductase), cytochrome P450 (cyt-p450) and cytochrome b5(cyt-b5). The activities of glutathione-metabolizing enzymes glutathione peroxidase(GPx), glutathione reductase (GR) and glucose-6-phospho dehydrogenase(G6PDH) were significantly lowered in lung-cancer bearing mice when compared with control mice. Piperine supplementation to tumour-induced animals significantly lowered the phase-I enzymes (NADPH-C reductase, cyt-p450 and cyt-b5)) and there was a rise in glutathione-metabolizing enzymes (GPx, GR and G6PDH), which indicated an antitumour and anti-cancer effect. Comparison of normal control mice and mice administered piperine only as drug control showed no significant variations in enzyme activities. Piprine administration to benzo(a)pyrene induced animals significantly increased the activities of mitochondrial enzymes, thereby suggesting its role in mitochondrial energy production.
 ...
PMID:Chemopreventive effect of piperine on mitochondrial TCA cycle and phase-I and glutathione-metabolizing enzymes in benzo(a)pyrene induced lung carcinogenesis in Swiss albino mice. 1588 60