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PubMed1981

Genetic polymorphism in three species of tsetse flies (Diptera: Glossinidae) in Upper Volta.

Natural populations of Glossina morsitans submorsitans Newstead, Glossina palpalis gambiensis Vanderplank and Glossina tachinoides Westwood occurring within 150 km of Bobo-Dioulasso, Upper Volta were examined using polyacrylamide gel electrophoresis. No variation was found in the banding pattern for arginine phosphokinase (EC 2.7.3.3). G. p. gambiensis and G. tachinoides had three alleles for each of the thoracic enzymes octanol dehydrogenase (EC 1.1.1.73), malic dehydrogenase (EC 1.1.1.37) and alpha-glycerophosphate dehydrogenase (EC 1.1.1.8) and for midgut alkaline phosphatase (EC 3.1.3.1). The same situation was found with G. m. submorsitans except that only two alleles for alpha-glycerophosphate dehydrogenase and one for alkaline phosphatase were found. In each species, and for each of the enzymes, one allele was present at a frequency of 95% or greater. There was little or no variation between populations. Two laboratory colonies of G. p. gambiensis had less genetic variation than wild populations.

Alcohol Oxidoreductases↗

PubMed1981

[Effect of thyroxine on the activity of a series of mitochondrial enzymes during the process of development].

The activity of alpha-glycerophosphate dehydrogenase and succinate dehydrogenase suffers almost no changes during the chick embryogenesis, whereas the activity of cytochrome oxidase increases by 20--25%. The activity of these enzymes in the embryos exceeded that in the adult birds. The injection of thyroxine during embryogenesis did not affect the activity of the enzymes under study but in chickens stimulated the activity of mitochondrial enzymes. The increase of activity of alpha-glycerophosphate dehydrogenase, cytochrome oxidase and succinate dehydrogenase was also noted in young rats.

Age Factors↗

PubMedDate not supplied

[Alkaline phosphomonohydrolases of Pacinian corpuscles].

Research on quantitative determination of activity of alkaline phosphatase (EC) 3.1.3.1) and 5'-nucleotidase (EC 3.1.3.5) of Pacinian corpuscles was performed. Two enzymes are shown to be different, which are distinguished by the pH optimum and substrate concentration. Alkaline phosphatase is found to be more active in splitting glycerophosphates. The alkaline phosphatase activity towards beta-glycerophosphate and alpha-naphthylphosphate is caused by various enzyme molecular forms with different electrophoretic mobility. The phosphatase and 5'-nucleotidase are shown to be activated by Mg2+ and Ca2+.

5'-Nucleotidase↗

PubMed1983

Lactate dehydrogenase A-subunit and B-subunit deficiencies: comparison of the physiological roles of LDH isozymes.

Different clinical features exist for lactate dehydrogenase A-subunit and B-subunit deficiencies. The metabolic basis for these clinical differences was elucidated by investigating carbohydrate metabolism in the affected tissues. Glycolysis was markedly retarded at the position of glyceraldehyde 3-phosphate dehydrogenase, and significant increases of glyceraldehyde 3-phosphate, dihydroxyacetone phosphate, and fructose 1,6-diphosphate were observed. The physical and kinetic properties of glyceraldehyde 3-phosphate dehydrogenase prepared from human erythrocytes and skeletal muscle were almost identical, but the mode of inhibition of the enzyme was slightly different in erythrocytes and in skeletal muscle. In erythrocytes, impaired reoxidation of NADH followed by the deficiency of substrate NAD+ causes a reduction of glyceraldehyde 3-phosphate dehydrogenase activity. However, in skeletal muscle, the increased level of NADH markedly inhibits the enzyme under anaerobic conditions. A flux of triose phosphates from glycolysis occurred in skeletal muscle of a patient with A-subunit deficiency. This flux is attributable to the high cytosol alpha-glycerophosphate dehydrogenase activity in skeletal muscle. for these reasons the ATP production was significantly impaired in the patient and the damage to muscle cells brings about the release of cytosolic enzymes and muscle rigidity after hard exercise. In contrast in the erythrocytes, the level of alpha-glycerophosphate dehydrogenase is very low and another red cell-specific NADH reoxidizing system such as NADH-cytochrome b5 reductase (NADH-methemoglobin reductase) is operating. In this manner, the NAD+ level in erythrocytes is compensated for without the flux of triose phosphates derived from glucose. Therefore, the ATP production in erythrocytes is sufficiently maintained by glycolysis even in a patient with complete lactate dehydrogenase B-subunit deficiency. Thus, impaired ATP production in anaerobic stage is a condition which is specific for lactate dehydrogenase A-subunit deficiency but does not occur for B-subunit deficiency. The different clinical features of the A- and B-subunit deficiencies have been clearly elucidated.

Erythrocytes↗

PubMed1984

Products of phosphatidylglycerol turnover in two Bacillus strains with and without lipoteichoic acid in the cells.

In order to understand the phosphatidylglycerol turnover mechanism, especially the differential turnover of diacylated and unacylated glycerol moieties of the lipid, products of phosphatidylglycerol metabolism were surveyed in vivo in Bacillus subtilis W23 and an alkalophile, Bacillus sp. strain A007. When cells of B. subtilis W23 labeled with radioactive glycerol were chased, lipoteichoic acid accumulated 90% of the radioactivity lost from the unacylated glycerol moiety of phosphatidylglycerol. Also, lipids other that phosphatidylglycerol, except diacylglycerol, and glycerol and glycerophosphate incorporated much less radioactivity. The [32P]phosphoryl group was also transferred from phosphatidylglycerol to lipoteichoic acid almost quantitatively in B. subtilis W23. A unique metabolism of phosphatidylglycerol was found in Bacillus sp. strain A007 which lacked phosphoglycolipid and lipoteichoic acid, that is, the turnover of phosphatidylglycerol of this organism was less extensive compared with that of B. subtilis W23, and both glycerol moieties of the lipid were metabolized at an identical rate. These results suggested that the major reaction involved in the turnover of phosphatidylglycerol was the transfer of glycerophosphate residue to lipoteichoic acid in a bacterium which possessed lipoteichoic acid and that several minor reactions also were involved in phosphatidylglycerol turnover.

Bacillus↗

PubMed1984

In situ biochemical studies of intestinal alkaline phosphatase in normal and phosphate-depleted rats by microdensitometry.

A quantitative microdensitometric study has been designed to characterize in situ intestinal brush border-bound alkaline phosphatase of rat duodenal villosities. Intestinal slices were incubated with beta-glycerophosphate as substrate. Free phosphate liberated was precipitated in presence of a lead reagent as lead sulfide. The precipitate was quantified in situ by scanning and integrating microdensitometry. Kinetic parameters of the reaction were determined at 37 degrees C, pH 8.8, in the middle part of the villosities. Apparent Michaelis constant (Km) for beta-glycerophosphate was found to be 8.16 +/- 0.56 mM (mean +/- S.E.). Maximal enzyme activation was obtained at pH 8.5. Maximal inhibition of enzyme activity was observed in the presence of L-phenylalanine (30 mM) or theophylline (5 mM). Along the villosity axis, enzyme activity rose from the crypt up to the midportion of the villosity and finally decreased at the tip region. In phosphate-depleted rats, enzyme activity was increased in all portions of the villosity, with conservation of the same activity gradient. In this situation, kinetic analysis showed a marked decrease of Km, i.e. 4.56 +/- 0.39 mM (mean +/- S.E.) as compared to normal rats.

Alkaline Phosphatase↗

PubMed1983

[Electron microscopic-cytochemical method of determining cell phagolysosomal structures].

A new electron-cytochemical method for detection of phagolysosomal structures in intact cells is proposed, which is more susceptible and simple in comparison with methods described elsewhere. The new method involves the addition of sodium beta-glycerophosphate and Pb(NO3)2 to the medium where phagocytes are incubated with phagocytic material. After the fusion of a phagosome containing the phagocytic material, sodium beta-glycerophosphate (the substrate for a marker lysosomal enzyme--acid phosphatase) and Pb2+ with primary lysosomes, hydrolysis of this substrate occurs with the eventual appearance of a deposit of Pb3(PO4)2.

Animals↗

PubMed1984

Enzyme activities and isozyme patterns in human lung tumors.

The isozyme patterns and activities of six enzymes were determined in surgical biopsy samples of lung tumors and non-neoplastic pulmonary areas. Fetal lungs were also examined. No tissue differences were found in the isozyme pattern of hexokinase or alkaline phosphatase; small differences in pyruvate kinase isozyme proportions were observed. The tumors exhibited significant deviations with respect to the lactate dehydrogenase (LDH) and malate dehydrogenase (MDH) isozyme patterns. Despite the diversity of cell types, the proportions of the M-subunit of LDH in each tumor and that of the mitochondrial isozyme of MDH in all but one tumor were higher than in control samples from the same lung. In contrast, the normal fetal lung showed a higher LDH-H proportion than did adult lung and a mature MDH isozyme pattern. The alpha-glycerophosphate dehydrogenase and adenylate kinase activities of the tumors were about one-tenth and one-fourth, respectively, of those of nonneoplastic adult lung. These lower activities (evident also in normal fetal lung) were accompanied by 3- to 5-fold increases in the LDH, MDH, pyruvate kinase, and hexokinase activities of the tumors; fetal lungs had lesser increases (2- to 3-fold) for the first 3 enzymes. The common features of tumors with different cell types and histological grade identified here point to several enzymes the quantitation or isozyme analysis of which may be of practical use in distinguishing cancerous from nonneoplastic human lung samples. A combination of different indicators, such as opposite changes in LDH and alpha-glycerophosphate dehydrogenase activity, coupled with elevated proportions of LDH-M, may be used to diagnose neoplasia most reliably.

Alkaline Phosphatase↗

PubMed1980

[Circadian rhythm and aging].

The circadian variation of several lipogenic enzymes of rat liver and of serum triglyceride and insulin levels was measured in dependence on age. In female rats of the Wistar strain subjected to a 12 hr light--12 hr darkness schedule malic enzyme and isocitrate dehydrogenase show a circadian cycle with maximum activities in the dark period, alpha-glycerophosphate dehydrogenase has a maximum at 14,00 hr. The circadian rhythm of these enzymes is synchronous in young and old animals, but the activities of malic enzyme and alpha-glycerophosphate dehydrogenase are lower in the liver of 18 months old rats in contrast to 3 months old animals at all time points. The activity of glucose-6-phosphate dehydrogenase of the liver of young rats increases during the light period and reaches a maximum at night. The enzyme in old animals does not show this circadian rhythm. There is no age-dependence of the circadian variation of serum triglyceride and insulin levels.

Aging↗

PubMed1982

[Subcellular localization of some enzymes in silkworm eggs].

Differential centrifugation of the silkworm (Bombyx mori L.) egg homogenates resulted in nuclear, mitochondrial, lysosomal and cytosol infarctions, which were analyzed for the activities of alanine, aspartate- and tyrosine aminotransferases, 3-glycerophosphate- and lactate dehydrogenases and acid and alkaline DNAases. Alanine- and aspartate aminotransferases as well as 3-glycerophosphate dehydrogenase are localized mainly in the cytosol, where their activities made up to 86.2, 95.4 and 98.4% of their total activity, respectively. The activities of lactate dehydrogenase and acid DNAase are distributed between the nuclear and mitochondrial fractions; this distribution is even in the case of the former enzyme, whereas in the case of the latter the bulk (90.6%) of total enzyme activity is found in the nuclei. In contrast to the other enzymes whose activity is distributed between different cell fractions, tyrosine aminotransferase is localized exclusively in mitochondria, while alkaline DNAase--exclusively in the nuclei. No correlation between the level of enzyme specific activity and its total content in the fractions was established. The role of the enzymes under study in silkworm metabolism is discussed.

Animals↗

PubMedDate not supplied

[Selection method and the characteristics of a cytochrome (a+a3)-deficient mutant of Candida parapsilosis yeasts].

A method was developed for selecting cytochrome-deficient mutants of yeast Candida parapsilosis; the method is based on determining the rate of inhibition of oxygen uptake by benzhydroxamic acid, an inhibitor of cyanide-resistant oxidase in the cells of preliminarily obtained yeast mutants. The mutant (C. parapsilosis bhas-1) lacks cytochrome a+a3, contains the same quantity of cytochrome b as the wild strain and a twice as low quantity of cytochrome c. In contrast to the wild strain, the mutant does not grow on ethanol for the first two days but, being cultivated further (up to 5 days), in a medium with ethanol, it resumes its capability to utilize ethanol as a carbon and energy source. Prolonged cultivation in the medium with ethanol induces the biosynthesis of cytochrome oxidase while cytochrome a+a3 is not induced in a medium supplied with glucose. The biomass accumulated by the mutant in the medium with glucose is twice as low comparing to that of the wild strain. The oxidative activity of the mutant mitochondria involves cyanide, resistant oxidase. The mitochondria of the mutant oxidize NAD-dependent substrates, NADH, NADPH, succinate, alpha-glycerophosphate, ethanol and lactate. The mitochondria have a low respiratory control and phosphorylate ADP while oxidizing NAD-dependent substrates, ethanol and lactate, but not alpha-glycerophosphate, succinate, NADH and NADPH.

Candida↗

PubMed1982

Early changes in renal distal convoluted tubules and collecting ducts of lithium-treated rats: light microscopy, enzyme histochemistry, and 3H-thymidine autoradiography.

The early effects of lithium on the kidney were studied in rats receiving a moderate daily dose (serum-Li: 0.5 to 0.8 mM per liter) for 3, 7, and 21 days. Enzyme histochemical reactions for acid and alkaline phosphatase, glucose 6-phosphatase, succinate and alpha-glycerophosphate dehydrogenase, and NADH tetrazolium reductase revealed changes confined to distal convoluted tubules and collecting ducts. The distal convoluted were unchanged at 3 days of treatment. At 7 days, a decrease in succinate dehydrogenase and NADH tetrazolium reductase and an increase in alpha-glycerophosphate dehydrogenase were noted. These changes were more conspicuous at 21 days and accompanied by tubular dilation and changes in light microscopic cellular morphology. In the collecting ducts, a cell enlargement and an increase in mitochondrial oxidative enzyme activities began to appear at 3 days, becoming more pronounced at 7 and particularly at 21 days. At 7 and even more at 21 days, a cellular hyperplasia was evident in the collecting ducts, and autoradiography after 3H-thymidine incorporation showed a marked increase in DNA synthesis in the collecting duct cells. The changes observed in the collecting ducts were most pronounced near the limit between the outer and the inner zone of the medulla. In conclusion, the rats developed morphologic changes at 3 to 7 days of treatment. The changes include (1) signs of cellular damage in the distal convoluted tubules and (2) hyperplasia and signs of increased functional activity in the collecting ducts.

Animals↗

PubMed1981

[Respiratory system of Endomyces magnusii. Properties of mitochondria from cells grown on glycerol].

Some peculiarities of oxidation of various substrates by tightly coupled highly energized mitochondria from the yeast Endomyces magnusii were studied. During cell growth on glycerol the formation of NADH and alpha-glycerophosphate in the hyaloplasm is paralleled with an adaptive synthesis of highly active dehydrogenases in the mitochondria. The dehydrogenases oxidize these substrates and are localized on the outer surface of the inner mitochondrial membrane. The reducing equivalents of the dehydrogenases enter the respiratory chain at the ubiquinone level by a shunt via the rotenone-sensitive site of the respiratory chain. Terminal oxidation of exogenous NADH, alpha-glycerophosphate and NAD-dependent substrates occurs in the cytochrome chain and is tightly coupled with phosphorylation. The ADP/O value is close to theoretical ones. Oxidation of succinate is partly mediated by alternate cyanide-resistant oxidase; the shunt-off of the electron flow between two alternate pathways is controlled by ADP. The tight coupling and theoretical efficiency of phosphorylation under succinate oxidation can take place only in the presence of salycyl hydroxamate, an alternate pathway inhibitor. A possible physiological role of alternate oxidase and the peculiarities of oxidation control at the individual substrate level are discussed.

Ascomycota↗

PubMed1978

[Development of the response of rabbit fetal tissues to thyroxine].

Development of rabbit fetal tissues sensitivity to thyroxin was studied on the basis of changes in alpha-glycerophosphate oxidase activity in the liver mitochondria of pregnant rabbits and their fetuses to which thyroxin was administered at different stages of pregnancy. T4 administration up to the 23rd day of gestation caused an increase in the enzyme activity in the maternal liver mitochondria only, whereas in the fetus it was at the control level. From the 24th day of pregnancy an increase of the alpha-glycerophosphate oxidase activity was seen in the fetal liver mitochondria. This can be explained by the appearance of rabbit fetal tissues sensitivity to maternal thyroxin at this period of gestation, increasing by the end of pregnancy.

Animals↗

PubMed1980

[Biochemical studies on muscles in neurogenic atrophies and central paralysis. Studies of the trophic functions of neurons].

Enzyme activities of the energy supplying metabolism were investigated in muscle specimens of brachial biceps, deltoid or anterior tibial muscles of patients with traumatic nerve lesions, polyneuropathies, Charcot-Marie-Tooth disease, amyotrophic lateral sclerosis, spinal muscular atrophy and hemiparesis. The key enzymes of glycogenolysis (glycogen phosphorylase), glycolysis (triosephosphate dehydrogenase, lactate dehydrogenase), alpha-glycerophosphate cycle (alpha-glycerophosphate dehydrogenase), beta-oxidation of fatty acids (beta-hydroxy-acyl-CoA-dehydrogenase), citrate acid cycle (citrate synthase, malate dehydrogenase), hexokinase reaction (hexokinase) and pentosephosphate shunt (6-phosphogluconate dehydrogenase) were measured. The present study shows that in case of disorders of the lower motor neuron--especially those with impaired axoplasmic transport--changes in the enzyme patterns of muscles occur at an early stage. The glycolytic enzyme activities are of particular significance because they are the most sensitive indicators of the onset, extent and course of neurogenic atrophy. There is a good correlation between severity of the lesion, functional state of the muscles and reduction of these enzyme activities. In case of traumatic nerve lesions re-innervation can prevent a permanent reduction of glycolytic enzymes only if it occurs during the first months after denervation. In all cases in which operative revision is considered, it is therefore not advisible to wait since the regenerative capacity of the motor neuron is not the only limiting factor but also the biochemical and morphological changes in the muscle fibre. These are permanent after long lasting denervation without re-innervation within the first months. Primary neuroaxonal degeneration of the nerve fibre which was found in the majority of our alcoholic patients obviously impairs the metabolism of the muscle to a greater extent than primary demyelination most frequently observed in diabetics with polyneuropathy. Corresponding to the chronic course of the illness over years and to the severity of the pareses, drastic reduction in the activities of glycolytic enzymes was found in patients with Charcot-Marie-Tooth disease. Simultaneously the activity of 6-phosphogluconate dehydrogenase was significantly increased as a result of the chronic neurogenic lesion of the muscle fibres. Follow-up during the treatment of diseases of the lower motor neuron can be performed because the enzyme activities can be measured even in small muscle specimens. In patients with hemiparesis slight but not significant reduction in the glycolytic enzyme activities was found by comparison with a normal control group. We assume that this reduction is due to general inactivity which is caused by the movement disorder rather than to the particular influence of the upper motor neuron.

Denervation↗

PubMed1995

[Changes in the infradian rhythm of the dehydrogenases in the blood lymphocytes of rats due to epiphysectomy and the action of weak alternating magnetic fields].

In experiments with 110 white inbred male rats, the infradian rhythm changes in succinate- and alpha-glycerophosphate dehydrogenases in rat's lymphocytes due to epiphysectomy, exposure to transitory magnetic field (TrMF) at 8 Hz and 5 microTl, and their combined effect were studied. According to spectral analysis, the infradian rhythms of lymphocyte succinate dehydrogenase, alpha-glycerophosphate dehydrogenase mean activities in intact animals amounted to 26.5 +/- 2.5; 19.1 +/- 1.1; 13.5 +/- 1.1; 9.1 +/- 0.8; 6.9 +/- 0.7; 3.6 +/- 0.2 days. Epiphysectomy decreases the observed rhythm amplitudes, shifts phases, disrupts temporal organization of the redox processes, i.e., induces desynchronosis. TrPM at 8 Hz also causes desyncronosis in intact animals though less pronounced than in epiphysectomized rats. TrMP partially normalizes temporal organization of the dehydrogenase status in epiphysectomized rats. Our findings point to the possibility to apply TrMF for "functional epiphysectomy" of intact animals and, in case of desynchronoses, as biorhythm "time sensors".

Animals↗

PubMed1993

Skeletal muscle metabolic enzymes are altered by hyperbaric oxygenation treatments.

To test whether repeated HBO exposures would increase activity of skeletal muscle metabolic enzymes, 27 rabbits (3 groups) were exposed 90 min/day, 5 days/wk to either 100% O2 at 243 kPa (HBO), 100% O2 at 101 kPa (HIO), or 21% O2 at 101 kPa (CON). Four animals per group were killed after 2 wk treatment, and the remaining five per group were killed after 8 wk of treatment. Soleus, plantaris, and tibialis anterior muscles were removed, and the activities of adenylate kinase, alpha-glycerophosphate dehydrogenase, and citrate synthase were measured. After 8 wk there was no difference in enzyme activity between groups for either plantaris or tibialis anterior. In the soleus after 8 wk there was no difference between groups in adenylate kinase activity, but alpha-glycerophosphate dehydrogenase activity was 56% greater (P < 0.05) in HBO than in HIO and 50% greater than in CON, and citrate synthase activity in HBO was 24% greater (P < 0.05) than that in HIO and 36% greater than that in CON. Inasmuch as the soleus is a postural muscle, these results suggest that long-term HBO treatments can increase enzyme activity in an actively contracting muscle.

Adenylyl Cyclases↗

PubMed1993

[Glycerol-loading test in experimental acute renal failure using 31P magnetic resonance spectroscopy of the kidney].

We observed that administration of exogenous glycerol reduces beta-ATP level and increases glycerophosphate level using magnetic resonance spectroscopy (MRS) of the kidney. A new "glycerol-loading test" for use with MRS in rats was developed. Sprague-Dawley rats were anesthetized and the left kidney was exposed and placed on surface coil. 31P-MRS (109.25MHz) of the kidney was performed using 10 microseconds, 90' pulse width and 2.308 sec repetition time with an accumulation of 200 times. MRS was performed 24 hours after induction of acute renal failure in each model of acute renal failure. Glycerol-loading test was performed by the intravenous infusion of 10% glycerol through jugular vein over a 60 min period. MRS was recorded every 10 min during glycerol infusion and for 60 min after cessation of infusion. In normal rats, beta-ATP level in the kidney was decreased to 52.0% of the pre-loading value at 55 min glycerol infusion and recovered to 66.7% 55 min after glycerol infusion was stopped. In the cisplatinum model, the reduction of beta-ATP and the increase of glycerophosphate levels following glycerol-loading was similar to that in normal rats; however, the recovery of beta-ATP level after infusion was stopped was weaker. Rats treated with glycerol and HgCl2 showed rather severe acute renal failure, but the beta-ATP level at 55 min glycerol infusion was 87.3% and 92.4%, respectively, showing difference from that in normal rats. No uptake of glycerol was observed 3 hours after 45 min pedicle clamping.(ABSTRACT TRUNCATED AT 250 WORDS)

Acute Kidney Injury↗