Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P06889 (Mol)
 630,302 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

In the adipose tissue, besides fatty acid synthesis (FA-S) from glucose, which includes several mitochondrial steps, FA-S from glutamate has been demonstrated. FA-S from glutamate takes place in the cytosol through the backward pathway of Krebs cycle (BPKC) and is due to the sequential action of (1) alanine aminotransferase (ALT, EC 2.6.1.2), which is presence of pyruvate converts glutamate to oxoglutarate; (2) isocitrate dehydrogenase (NADP) (ICDH, EC 1.1.1.42), which converts oxoglutarate to isocitrate; (3) aconitate hydratase (ACO, EC 4.2.1.3), which transforms isocitrate to citrate: and (4) ATP citrate-lyase (ATP-CL, EC 4.1.3.8), which splits citrate to yield the acetyl-CoA needed for FA-S. We studied the enzymes involved in BPKC in homogenates of human adipose tissue. In normal subjects, the cytosolic activity (mumol/min/g protein) was: ALT = 10.3 +/- 1.1, ICDH = 29.5 +/- 2.8, ACO = 2.05 +/- 0.23, and ATP-CL = 1.2 +/- 0.2. Mitochondria contained less or no activity, values being 20, 9, 11, and 0% of total for ATL, ICDH, ACO, and ATP-CL, respectively. BPKC enzymes are more active than the enzymes limiting FA-S from glucose, i.e., phosphofructokinase (EC 2.7.1.11), pyruvate carboxylase (EC 6.4.1.1), and pyruvate dehydrogenase (EC 1.2.4.1). In the obese patients, cytosolic ALT and ATP-CL were increased (12.9 +/- 0.7, P < 0.05, and 2.28 +/- 0.27, P < 0.01, respectively) compared to normal, while ICDH was not changed (ACO could not be studied). Similar changes were obtained by expressing enzyme activity per fat cell number.(ABSTRACT TRUNCATED AT 250 WORDS)
Biochem Mol Med 1995 Feb
PMID:Fatty acid synthesis from glutamate in the adipose tissue of normal subjects and obese patients: an enzyme study. 755 12

Erythrocyte aspartate aminotransferase (AST) and alanine aminotransferase (ALT) activities are often used as indices of vitamin B-6 nutritional status; however, results using a mixed population of erythrocytes can be quite variable. Erythrocytes from two strains of mice (Mus domesticus), A/Ibg and DBA/Ibg, were separated according to age by centrifugation through discontinuous Percoll density gradients into three fractions: top (least dense, youngest), middle and bottom (most dense, oldest). A sufficient yield of age-fractionated erythrocytes was obtained from a single mouse for all of the enzyme measurements. The activities of AST, ALT and three age-marker enzymes, pyruvate kinase, acetylcholinesterase and hexokinase, were found to be significantly higher in the youngest cell fractions, and declined in the older, more dense fractions. A mice had significantly lower AST and ALT activities in the age separated fractions than did DBA mice. The measurement of enzyme activities in low density, young cells may be especially useful in studies involving conditions in which the proportion of young erythrocytes may be elevated with respect to the entire erythrocyte mass.
Comp Biochem Physiol B Biochem Mol Biol
PMID:Aminotransferase activities in mouse, Mus domesticus, erythrocytes separated according to age. 755 57

The p53 tumor-suppressor gene is the most commonly altered gene in human cancers. Here we demonstrate that transcripts of the mdm2 gene, which encodes a cellular p53 binding protein, markedly increased in the rat liver within 1 to 3 h, reached a peak at 12 h and returned to the basal level 48 h after the administration of carbon tetrachloride. However, the level of hepatic mdm2 mRNA did not significantly change after partial hepatectomy. This is in contrast to p53 gene expression which increased after either procedure. C-myc transcripts also rapidly increased after the injection of carbon tetrachloride, reaching a maximal level at 3 h. The activity of serum alanine aminotransferase was low within the first 12 h and was maximal 24 h after carbon tetrachloride. These results suggest that the transient hepatic expression of the mdm2 gene prior to the onset of cell death is more likely to reflect events associated with necrosis rather than with cell proliferation.
Biochem Mol Biol Int 1995 Jun
PMID:Expression of the protooncogene mdm2 markedly increases in response to carbon tetrachloride but not after partial hepatectomy in contrast to p53. 766 43

The C57BL/10 SPS/sps mouse mutant are audiogenic seizure-susceptible. The enzymatic activities of glutamate decarboxylase (GAD), GABA aminotransferase (GABA-T), alanine aminotransferase (ALA-T), aspartate aminotransferase (ASP-T), and glutamate dehydrogenase (GDH) of whole brain supernatant are significantly reduced in these epileptic mice. GABA uptake is decreased in cortex, midbrain, and pons medulla. Previous studies showed the presence of two sodium-dependent GLU uptake systems in normal (SPS/SP) mice. Glutamate Umax by System 1 is significantly decreased in these mice, whereas the Umax value for System 2 is significantly increased in the epileptic mice.
Mol Neurobiol
PMID:Altered GABAergic and glutamatergic transmission in audiogenic seizure-susceptible mice. 788 3

Hepatic and renal subacute toxicity induced by the antineoplastic drugs chlorambucil, cisplatin, epirubicin and methotrexate and the steroid alkylating agent 3 beta-hydroxy-13 alpha-amino-13,17-seco-5 alpha-androstan-17-oic-13, 17-lactam (p-[bis(2-chloroethyl) amino] phenyl) acetate was investigated in rats using serum biochemical parameters. Toxicological evaluation was performed in serum samples following the administration of dose regimens of the agents that were previously shown to be effective in suppressing malignant tumor growth or to prolong survival in tumor bearing animals. Hepatic and renal subacute toxicity was evaluated by measuring enzyme activity or concentrations of: alanine aminotransferase, alkaline phosphatase, aspartate aminotransferase, total cholesterol, gamma-glutamyltransferase, glucose, potassium, sodium, blood urea nitrogen and uric acid. The use of the above serum biochemical parameters indicated that the overall toxicity impact of the antitumor drugs was methotrexate < cisplatin < epirubicin < chlorambucil. The homo-azasteroid ester only transiently affected the biochemical parameters associated with renal toxicity, while it affected some of the biochemical parameters associated with hepatic toxicity, though to a significantly lower extent than the antitumor drugs.
Biochem Mol Biol Int 1993 Nov
PMID:Evaluation of kidney and liver subacute toxicity of antitumor agents using serum biochemical parameters in rats. 790 82

The objective was to determine the effects of persistent obesity on amino acid enzymes in white (WAT) and brown (BAT) adipose tissues. Dietary obesity was induced by feeding a cafeteria diet ad libitum for 3 months, then it was removed and the obese animals received the same diet as controls for 5 months. Dietary-induced obesity was persistent as obese rats showed a stable, higher body weight than controls (26%). Key enzymes of alpha-amino nitrogen metabolism were studied and results showed reduced activities in obese rats: glutamine synthetase (45%), AMP deaminase (52%), alanine aminotransferase (66%) and glutamate dehydrogenase (68%) in BAT, whereas WAT of obese animals only showed lower aspartate aminotransferase activity (47%) with respect to the controls. We can conclude that these adaptations in amino acid metabolism were exclusively dependent on the obese status as they were observed in an obesity model in which obese rats eat the same diet as controls.
Biochem Mol Biol Int 1994 Apr
PMID:Brown and white adipose tissue adaptive enzymatic changes on amino acid metabolism in persistent dietary-obese rats. 791 90

Soluble alanine aminotransferase from rat liver was modified with 2,4-bis(O-methoxypolyethylene glycol)-6-chloro-s-triazine which was synthesized from monomethoxypolyethylene glycol and cyanuric chloride. The modified enzyme exhibited relative stability against extreme conditions of pH and temperature and also resistivity against tryptic digestion as compared to the native enzyme.
Biochem Mol Biol Int 1994 May
PMID:Effect of covalent attachment of polyethylene glycol on some properties of rat liver soluble alanine aminotransferase. 808 Dec 15

Detailed study of the effects of oxygen on the carbohydrate metabolism of Giardia lamblia revealed that low concentrations of oxygen (< 0.25 microM) produced profound alterations in the carbon balance of this organism. Although this concentration of oxygen could not be detected by mass spectrometry, a marked stimulation of ethanol production was observed. Associated with this was an inhibition of alanine production and oxidation of the intracellular NAD(P)H pool. Higher concentrations of oxygen inhibited ethanol production and further reduced levels of alanine. These results suggest that this stimulation is due to changes in carbon flux. Analysis of cell and medium hydrolysates after the growth of trophozoites in [U-14C]glucose suggests that G. lamblia does not synthesise detectable levels of labelled amino acids, except alanine and to a lesser extent valine, from this sugar. Trophozoites of G. lamblia have both glutamate dehydrogenase and alanine aminotransferase activity. As glutamate is taken up from the medium, it is suggested that glutamate dehydrogenase and alanine aminotransferase cooperate to convert pyruvate to alanine, with the concomitant oxidation of NAD(P)H.
Mol Biochem Parasitol 1993 Jan
PMID:The effects of oxygen on fermentation in Giardia lamblia. 809 74

Pathophysiological concentrations of ammonia, both in vivo and in vitro, suppressed the oxidation of glutamate by rat cerebellar mitochondria. The transport of glutamate into mitochondria was either unaltered or enhanced during hyperammonemic states. Activities of mitochondrial enzymes, aspartate aminotransferase, alanine aminotransferase, glutamate dehydrogenase, glutaminase, and GABA-transaminase were suppressed during hyperammonemic states. Suppression of 14CO2 production with (aminooxy)acetic acid but not with glutamic acid diethyl ester indicated that transamination but not oxidative deamination of glutamate plays a major role in glutamate oxidation during normal and hyperammonemic states.
Mol Chem Neuropathol 1993 Aug
PMID:Transport and metabolism of glutamate by rat cerebellar mitochondria during ammonia toxicity. 810 3

A 1.75 kb cDNA containing the entire coding sequence of the hypoxically inducible alanine aminotransferase (AlaAT) from barley roots was isolated and sequenced. This clone has an open reading frame of 1446 bp, and a deduced amino acid sequence of 482 residues, giving an estimated protein molecular mass of 52,885 Da. RNA blot analysis of barley root tissue showed a 4-fold increase of a single AlaAT-2 mRNA band after 12-24 hours of hypoxic stress, followed by a decrease in message levels after 48 h of hypoxic conditions. AlaAT-2 protein concentration increased in a similar pattern to AlaAT activity in root tissue, to almost 6-fold the aerobic level after 96 h of hypoxic stress. AlaAT-2 activity increased more than 2-fold in roots of Panicum miliaceum exposed to hypoxia, and is the same isoform as the light inducible AlaAT in P. miliaceum leaves. The unique expression patterns of AlaAT-2 in root and leaf tissue upon exposure to different environmental stimuli is also discussed.
Plant Mol Biol 1994 Feb
PMID:Hypoxically inducible barley alanine aminotransferase: cDNA cloning and expression analysis. 812 85


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