OBJECTIVETo study major human UGT isoforms involved in trans-resveratrol (TR) phase II metabolism.

METHODtrans-resveratrol and 12 major human UGT isoforms were incubated in vitro and then glucuronic acid metabolites were determined by HPLC-MS, in order to preliminarily analyze the structure and observe the effect of different UGT isoforms on the generation rate of glucuronic acid metabolites.

RESULTIn in vitro metabolic system, two metabolites-4'-O-monoglucuronide resveratrol (M-1) and 3-0-monoglucuronide resveratrol (M-2)-were generated from trans-resveratrol after being catalyzed by UGT. During the cause, generation of M-1 and M-2 were catalyzed by UGT1A1, UGT1A3, 1A8, 1A9 andlA10, whereas only UGT1A6 and 1A7 contributed to the forma-tion of M-2. Both the formation rate of M-1 and M-2 catalyzed by UGT1A1, 1A10 and the formation of M-2 catalyzed by UGT1A8 slowed down with the increasing concentration of substrates, causing the phenomenon of "substrate inhibition".

CONCLUSIONUGT1A1, 1A8, 1A9, 1A10 get involved in the formation of M-1, and of them UGTIA9 is the most important contributor. UGT1A3 also makes small contribution to the formation of M-1 and M-2, while other UGT isoforms show hardly any reaction with the trans-resveratrol phase II metabolites.

Glucuronic Acid ; metabolism ; Glucuronosyltransferase ; metabolism ; Humans ; Isoenzymes ; metabolism ; Kinetics ; Stilbenes ; chemistry ; metabolism

AIMTo explore the adapting metabolic mechanisms of the plateau zokors to the hypoxic-hypercapnic environment.

METHODSThe activities of lactate dehydrogenase in serum and tissues, and the content of lactate in serum of plateau zokors in spring, summer and autumn were determined by using method of enzyme analysis. The spectrums of lactate dehydrogenase isoenzymes in serum and tissues of plateau zokors in spring, summer and autumn were analyzed by using method of the discontinuous systemic poly-acrylamide perpendicular plank gel electrophoresis.

RESULTSThe activities of lactate dehydrogenase in serum had obvious seasonally difference that were higher in spring and lower in autumn, and the content of lactate in serum showed same changing pattern. The spectrums of lactate dehydrogenase isoenzymes in serum showed five bands that were LDH1, LDH2, LDH3, LDH4 and LDH5 from positive pole to negative pole respectively, it showed clearly two bands in serum of summer that were LDH4 and LDH5 and one band in serum of autumn that was LDH5. The activities of LDH in tissues of skeleton muscle, cardiac muscle and brain were higher compared with the other tissues, it decreased markedly from spring to summer to autumn. In tissues of liver, kidney and lungs, activities of LDH were lower. Activities of LDH in livers, were significantly higher in spring compared that in summer and autumn, which had no obvious difference between summer and autumn. Activities of LDH in kidneys and lungs, showed no obviously difference between spring and summer, which decreased markedly in autumn. The spectrums of lactate dehydrogenase isoenzymes in tissues of cardiac muscle, liver, lungs, kidney, brain and skeleton muscle showed five bands, the spectrums were obvious different in different tissues, and the content of LDH isoenzymes showed seasonal changes in different tissues.

CONCLUSIONGlycolysis levels in plateau zokors had obvious seasonally change which increased in spring and decreased in autumn significantly. It related to the activity of plateau zokors in different seasons and seasonal fluctuation of oxygen and carbon dioxide in burrows of plateau zokors.

Animals ; Carbon Dioxide ; metabolism ; Isoenzymes ; analysis ; metabolism ; L-Lactate Dehydrogenase ; analysis ; metabolism ; Rodentia ; metabolism ; Seasons

Aldehyde dehydrogenase 1 (ALDH1, ALDH1A1 or RALDH1), an enzyme responsible for the oxidation of intracellular aldehydes, was shown to have a function in the early differentiation of stem cells. Its activity shows promising potential as a universal marker for the identification and isolation of normal stem cells and cancer stem cells from multiple sources in a variety of tissue types. Herein, we review the available data reporting the utilization of ALDH1 activity as a means to identify and isolate normal stem cells and cancer stem cells (CSCs), and the potential diagnostic and therapeutic implications, with a special focus on the mammary gland and breast cancer. The research opportunity in this area of interest is emphasized.
Animals ; Biomarkers ; metabolism ; Biomarkers, Tumor ; metabolism ; Humans ; Isoenzymes ; metabolism ; Neoplastic Stem Cells ; metabolism ; Retinal Dehydrogenase ; metabolism ; Stem Cells ; metabolism

Phospholipase C (PLC)1 hydrolyzes phosphatidylinositol 4,5-bisphosphate to generate the second messengers, inositol 1,4,5-trisphosphate (IP3) and diacylglycerol (DAG). IP3 induces a transient increase in intracellular free Ca2+, while DAG directly activates protein kinase C. Upon stimulation of cells with growth factors, PLC-gamma1 is activated upon their association with and phosphorylation by receptor and non-receptor tyrosine kinases. In this review, we will focus on the activation mechanism and regulatory function of PLC-gamma1.
Cell Division ; Enzyme Activation ; Isoenzymes/metabolism* ; Phospholipase C/metabolism* ; Second Messenger Systems ; T-Lymphocytes

Lactic dehydrogenase (LDH) isozyme pattens were examined in rats after exposing the animal to 250 ppm of sulfur dioxide gas. The isozymes of the respective tissues were separated on cellulose-acetate strips from the brain, lung, heart, liver, kidneys, and muscle, and visualized as the isozyme bands by the formazan reaction and analyzed by densitometry. As well as the above experiment, room-air and room-air+SO2 were aerated through tissue homoenates in-vitro, accompanied by pure oxygen aeration in order to see the in vitro effect of the gases on the LDH activity in the tissues mentioned with the following conclusions. (1) The H-type of LDH activity dominated in the normal heart tissue of rats, M-type in the normal lung, liver, and muscle tissues of the animal. (2) The kidney tissue of normal rats exhibited preponderance of LDH-1 and-5 isozymes, brain tissue in LDH-1 and-4 isozymes. (3) When rats inhaled sulfur dioxide gas in the concentration of 250 ppm, it appeared that the M-type tended to predominate in the anaerobic tissues and the H-type in the aerobic tissue. (4) The degree of oxygen tension seemed to be correlated with the low level of LDH activity in the anaerobic tissues such as liver and muscle and with the increased activity in the aerobic tissues, such as heart and lung. (5) The low oxygen tension seems to favor syn-thesis of M-type LDH and high oxygen tesnion H-type LDH in the tissues of rats.
Air Pollution ; Animal ; Citric Acid Cycle ; Densitometry ; Electrophoresis ; Environmental Exposure ; Isoenzymes ; Lactate Dehydrogenase/metabolism* ; Oxygen/metabolism ; Rats ; Sulfur Dioxide/toxicity* ; Substances: ; Isoenzymes ; Sulfur Dioxide ; Oxygen ; Lactate Dehydrogenase

Extracellular ATP (exATP) has been known to be a critical ligand regulating skeletal muscle differentiation and contractibility. ExATP synthesis was greatly increased with the high level of adenylate kinase 1 (AK1) and ATP synthase beta during C2C12 myogenesis. The exATP synthesis was abolished by the knock-down of AK1 but not by that of ATP synthase beta in C2C12 myotubes, suggesting that AK1 is required for exATP synthesis in myotubes. However, membrane-bound AK1beta was not involved in exATP synthesis because its expression level was decreased during myogenesis in spite of its localization in the lipid rafts that contain various kinds of receptors and mediate cell signal transduction, cell migration, and differentiation. Interestingly, cytoplasmic AK1 was secreted from C2C12 myotubes but not from C2C12 myoblasts. Taken together all these data, we can conclude that AK1 secretion is required for the exATP generation in myotubes.
Adenosine Triphosphate/*biosynthesis ; Adenylate Kinase/*metabolism ; Animals ; Cell Line ; Extracellular Space/metabolism ; Isoenzymes/*metabolism ; Mice ; Muscles/cytology/*metabolism

1. Using the kidney of the rabbit weighing approximately 1.5kg the LDH isozymes, LDH-l through 5, were analyzed on the acetate strip by electrophoresis and it was found that the LDH-3 was the least active isozyme followed by the LDH-2, -4, -1, and -5 in increasing order of activity both in that cortex and the medulla, showing a specific distribution pattern in the two tissues. 2. The difference in the isozymic distribution pattern between the cortex and the medulla was confirmed by separating the H-and M-LDH by DEAE-cellulose, the ratio of M-/H-LDH being l. 441t the medulla and 3. O3 in the cortex, showing more active anaerobic metabolism in the latter than in the former. 3. The total activity of LDH in the 20% homogenate of the total kidney tissue was 10. 55 units/ml the cortical 2.98 units/ml. and the medullary 7. 37 unite/ml. 4. In the unilaterally nephrectomized rabbit. the cortex of the remaining kidney showed increased activities of both H- and M-LDH, but the medullary H-LDH decreased, resulting in increases of the ratio M-,H-LDH both in the cortex and in the medulla 5. In the unilaterally pedicle-clamped rabbit, LDH of the clamped kidney medulla decreased while that of the cortex increased, and LDH of the unclamped kidney showed elevated activity both in the cortex and in the medulla, yielding an increase in the ratio of M-/H-LDH. 6. The specific difference in distribution pattern of LDH igozymes between the cortex and the medulla of the rabbit kidney and an increase of the ratio of M-/H.LDH resulting from functional compensation following unilateral nephrectomy or pedicle clamping have been briefly discussed.
Compensation and Redress ; Constriction ; DEAE-Cellulose ; Electrophoresis ; Isoenzymes ; Kidney Medulla ; Kidney* ; Metabolism ; Nephrectomy ; Oxidoreductases*

Pharmacotherapy of bipolar disorder is a rapidly evolving field. Mood stabilizers and anticonvulsants have varying biochemical profiles which may predispose them to different adverse effects and drug-drug interactions. Several of the new anticonvulsants appear less likely to have the problems with drug-drug interaction. To provide more effective combination pharmacotherapies, clinicians should be allowed to anticipate and avoid pharmacokinetic and pharmacodynamic drug-drug interactions. We reviewed the role of cytochrome P450 isozymes in the metabolism of the drugs and their interactions. The drug-drug interactions of several classes of drugs which used as mood stabilizers and new anticonvulsants, some of which may have psychotropic profiles, are discussed mainly in this article. Finally, potential pharmacokinetic interactions between the benzodiazepines and other coadministered drugs are discussed briefly.
Anti-Anxiety Agents* ; Anticonvulsants ; Benzodiazepines ; Bipolar Disorder ; Cytochrome P-450 Enzyme System ; Drug Therapy ; Isoenzymes ; Metabolism

Plateau zokor (Myospalax baileyi) and plateau pika (Ochotona curzniae) are native to the Qinghai-Tibet plateau. To study their adaptive mechanisms, the ratios of heart weight to body weight (HW/BW) and right to left ventricular plus septum weights [RV/(LV+S)] were determined; the microvessel density (MVD) of cardiac muscle were measured by immunohistochemical staining; the numerical density on area (N(A)), volume density (V(V)), specific surface (δ), and surface density (S(V)) of mitochondria were obtained by microscopy and stereology; the contents of myoglobin (Mb) and lactic acid (LD), and the activity of lactate dehydrogenase (LDH) in cardiac muscle were analyzed by spectrophotometer. The results showed that the HW/BW of plateau zokor [(4.55±0.26)%] and plateau pika [(4.41±0.38)%] was significantly greater than that of Sprague-Dawley (SD) rat [(3.44±0.41)%] (P<0.05), but the RV/(LV+S) [(22.04±1.98)%, (25.53±3.41)%] was smaller than that of SD rats [(44.23±3.87)%] (P<0.05). The MVD and N(A) of cardiac muscle were 1688.631±250.253 and 0.768±0.123 in SD rat, 2002.888±367.466 and 0.868±0.159 in plateau pika and 2 990.643±389.888 and 1.012±0.133 in plateau zokor. The V(V) of mitochondria in plateau zokor (0.272±0.045) was significantly lower than that in plateau pika (0.343±0.039) and SD rat (0.321±0.048) (P<0.05), while the δ of mitochondria in plateau zokor (9.409±1.238) was higher than that in plateau pika (6.772±0.892) and SD rat (7.287±1.373) (P<0.05). The S(V) of mitochondria in plateau pika (2.322±0.347) was not obviously different from that in plateau zokor (2.468±0.380) and SD rat (2.227±0.377), but that in plateau zokor was significantly higher than that in SD rat (P<0.05). The contents of Mb in cardiac muscle of plateau zokor [(763.33±88.73) nmol/g] and plateau pika [(765.96±28.47) nmol/g] were significantly higher than that of SD rat [(492.38±72.14) nmol/g] (P<0.05), the content of LD in plateau zokor [(0.57±0.06) mmol/L] was obviously higher than that in plateau pika [(0.45±0.06) mmol/L] and SD rat [(0.48±0.02) mmol/L] (P<0.05), and the activity of LDH in plateau zokor [(16.90±2.00) U/mL] and plateau pika [(20.55±2.46) U/mL] were significantly lower than that in SD rat [(38.26±6.78) U/mL] (P<0.05). The percentage of LDH-H in cardiac muscle decreased in order in plateau zokor, plateau pika and SD rat. In conclusion, plateau zokor and plateau pika adapt better to hypoxia than SD rat by increasing the SV of mitochondria, MVD and content of Mb in the cardiac muscle. However, the parameters of mitochondria in the two high-altitude animals are different possibly because of the differences of habitats and habits.
Adaptation, Physiological ; Animals ; Heart ; physiology ; Hypoxia ; metabolism ; Isoenzymes ; metabolism ; L-Lactate Dehydrogenase ; metabolism ; Lagomorpha ; physiology ; Rats ; Rats, Sprague-Dawley ; Tibet

Albumin is the most abundant protein in human serum. A dye-binding method is commonly used in clinical laboratories for its estimation using different types of dyes. However, all these dye methods were interfered by a variety of compounds. Here we present a method for the detection of albumin in human serum and other biological fluids. The principle is based on the fact that lactate dehydrogenase isoenzyme-5 (LDH-5) binds specifically to Dextran-Blue (DB). Albumin inhibits the binding of LDH-5 with DB. Absence of LDH activity in DB fraction after gel filtration indicates the presence of albumin in sample and vice versa.
Chemistry, Clinical/*methods ; Chromatography, Gel ; Human ; Isoenzymes/metabolism ; Lactate Dehydrogenase/metabolism ; Protein Binding ; Sepharose/chemistry ; Serum Albumin/*analysis