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Sample records for lactate dehydrogenase creatine

  1. Microcomputer Assisted Interpretative Reporting of Sequential Creatine Kinase (CK) and Lactate Dehydrogenase (LDH) Isoenzyme Determination

    PubMed Central

    Talamo, Thomas S.; Losos, Frank J.; Mercer, Donald W.

    1984-01-01

    We have developed a microcomputer based system for interpretative reporting of creatine kinase (CK) and lactate dehydrogenase (LDH) isoenzyme studies. Patient demographic data and test results (total CK, CK-MB, LD-1, and LD-2) are entered manually through the keyboard. The test results are compared with normal range values and an interpretative report is generated. This report consists of all pertinent demographic information with a graphic display of up to 12 previous CK and LDH isoenzyme determinations. Diagnostic interpretative statements are printed beneath the graphic display following analysis of previously entered test results. The combination of graphic data display and interpretations based on analysis of up to 12 previous specimens provides useful and accurate information to the cardiologist.

  2. Common and rare variants associating with serum levels of creatine kinase and lactate dehydrogenase.

    PubMed

    Kristjansson, Ragnar P; Oddsson, Asmundur; Helgason, Hannes; Sveinbjornsson, Gardar; Arnadottir, Gudny A; Jensson, Brynjar O; Jonasdottir, Aslaug; Jonasdottir, Adalbjorg; Bragi Walters, G; Sulem, Gerald; Oskarsdottir, Arna; Benonisdottir, Stefania; Davidsson, Olafur B; Masson, Gisli; Th Magnusson, Olafur; Holm, Hilma; Sigurdardottir, Olof; Jonsdottir, Ingileif; Eyjolfsson, Gudmundur I; Olafsson, Isleifur; Gudbjartsson, Daniel F; Thorsteinsdottir, Unnur; Sulem, Patrick; Stefansson, Kari

    2016-01-01

    Creatine kinase (CK) and lactate dehydrogenase (LDH) are widely used markers of tissue damage. To search for sequence variants influencing serum levels of CK and LDH, 28.3 million sequence variants identified through whole-genome sequencing of 2,636 Icelanders were imputed into 63,159 and 98,585 people with CK and LDH measurements, respectively. Here we describe 13 variants associating with serum CK and 16 with LDH levels, including four that associate with both. Among those, 15 are non-synonymous variants and 12 have a minor allele frequency below 5%. We report sequence variants in genes encoding the enzymes being measured (CKM and LDHA), as well as in genes linked to muscular (ANO5) and immune/inflammatory function (CD163/CD163L1, CSF1, CFH, HLA-DQB1, LILRB5, NINJ1 and STAB1). A number of the genes are linked to the mononuclear/phagocyte system and clearance of enzymes from the serum. This highlights the variety in the sources of normal diversity in serum levels of enzymes. PMID:26838040

  3. Common and rare variants associating with serum levels of creatine kinase and lactate dehydrogenase

    PubMed Central

    Kristjansson, Ragnar P.; Oddsson, Asmundur; Helgason, Hannes; Sveinbjornsson, Gardar; Arnadottir, Gudny A.; Jensson, Brynjar O.; Jonasdottir, Aslaug; Jonasdottir, Adalbjorg; Bragi Walters, G.; Sulem, Gerald; Oskarsdottir, Arna; Benonisdottir, Stefania; Davidsson, Olafur B.; Masson, Gisli; Th Magnusson, Olafur; Holm, Hilma; Sigurdardottir, Olof; Jonsdottir, Ingileif; Eyjolfsson, Gudmundur I.; Olafsson, Isleifur; Gudbjartsson, Daniel F.; Thorsteinsdottir, Unnur; Sulem, Patrick; Stefansson, Kari

    2016-01-01

    Creatine kinase (CK) and lactate dehydrogenase (LDH) are widely used markers of tissue damage. To search for sequence variants influencing serum levels of CK and LDH, 28.3 million sequence variants identified through whole-genome sequencing of 2,636 Icelanders were imputed into 63,159 and 98,585 people with CK and LDH measurements, respectively. Here we describe 13 variants associating with serum CK and 16 with LDH levels, including four that associate with both. Among those, 15 are non-synonymous variants and 12 have a minor allele frequency below 5%. We report sequence variants in genes encoding the enzymes being measured (CKM and LDHA), as well as in genes linked to muscular (ANO5) and immune/inflammatory function (CD163/CD163L1, CSF1, CFH, HLA-DQB1, LILRB5, NINJ1 and STAB1). A number of the genes are linked to the mononuclear/phagocyte system and clearance of enzymes from the serum. This highlights the variety in the sources of normal diversity in serum levels of enzymes. PMID:26838040

  4. Relationship of creatine kinase, aspartate aminotransferase, lactate dehydrogenase, and proteinuria to cardiomyopathy in the owl monkey (Aotus vociferans)

    SciTech Connect

    Gozalo, Alfonso S.; Chavera, Alfonso; Montoya, Enrique J.; Takano, Juan; Weller, Richard E.

    2008-02-01

    The purpose of this study was to determine serum reference values for crea- tine kinase (CK), aspartate aminotransferase (AST), and lactate dehydroge- nase (LDH) in captive-born and wild-caught owl monkeys to assess their usefulness for diagnosing myocardial disease. Urine samples were also collected and semi-quantitative tests performed. There was no statistically significant difference between CK, AST, and LDH when comparing both groups. However, when comparing monkeys with proteinuria to those without proteinuria, a statistically significant difference in CK value was observed (P = 0.021). In addition, the CK/AST ratio revealed that 29% of the animals included in this study had values suggesting cardiac infarction. Grossly, cardiac concentric hypertrophy of the left ventricle and small, pitted kidneys were the most common findings. Microscopically, myocardial fibrosis, contraction band necrosis, hypertrophy and hyperplasia of coronary arteries, medium-sized renal arteries, and afferent glomerular arteriolae were the most significant lesions, along with increased mesangial matrix and hypercellularity of glomeruli, Bowman’s capsule, and peritubular space fibroplasia. These findings suggest that CK, AST, and LDH along with urinalysis provide a reliable method for diagnosing cardiomyopathies in the owl monkey. In addition, CK/AST ratio, proteinuria, and the observed histological and ultrastructural changes suggest that Aotus vociferans suffer from arterial hypertension and chronic myocardial infarction.

  5. Lactate dehydrogenase-elevating virus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This book chapter describes the taxonomic classification of Lactate dehydrogenase-elevating virus (LDV). Included are: host, genome, classification, morphology, physicochemical and physical properties, nucleic acid, proteins, lipids, carbohydrates, geographic range, phylogenetic properties, biologic...

  6. Lactate dehydrogenase in Phycomyces blakesleeanus.

    PubMed Central

    Soler, J; De Arriaga, D; Busto, F; Cadenas, E

    1982-01-01

    1. An NAD-specific L(+)-lactate dehydrogenase (EC 1.1.1.27) from the mycelium of Phycomyces blakesleeanus N.R.R.L. 1555 (-) was purified approximately 700-fold. The enzyme has a molecular weight of 135,000-140,000. The purified enzyme gave a single, catalytically active, protein band after polyacrylamide-gel electrophoresis. It shows optimum activity between pH 6.7 and 7.5. 2. The Phycomyces blakesleeanus lactate dehydrogenase exhibits homotropic interactions with its substrate, pyruvate, and its coenzyme, NADH, at pH 7.5, indicating the existence of multiple binding sites in the enzyme for these ligands. 3. At pH 6.0, the enzyme shows high substrate inhibition by pyruvate. 3-hydroxypyruvate and 2-oxovalerate exhibit an analogous effect, whereas glyoxylate does not, when tested as substrates at the same pH. 4. At pH 7.5, ATP, which inhibits the enzyme, acts competitively with NADH and pyruvate, whereas at pH 6.0 and low concentrations of ATP it behaves in a allosteric manner as inhibitor with respect to NADH, GTP, however, has no effect under the same experimental conditions. 5. Partially purified enzyme from sporangiophores behaves in entirely similar kinetic manner as the one exhibited by the enzyme from mycelium. PMID:7115293

  7. 21 CFR 862.1440 - Lactate dehydrogenase test system.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Lactate dehydrogenase test system. 862.1440... Systems § 862.1440 Lactate dehydrogenase test system. (a) Identification. A lactate dehydrogenase test system is a device intended to measure the activity of the enzyme lactate dehydrogenase in serum....

  8. 21 CFR 862.1440 - Lactate dehydrogenase test system.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Lactate dehydrogenase test system. 862.1440... Systems § 862.1440 Lactate dehydrogenase test system. (a) Identification. A lactate dehydrogenase test system is a device intended to measure the activity of the enzyme lactate dehydrogenase in serum....

  9. 21 CFR 862.1440 - Lactate dehydrogenase test system.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Lactate dehydrogenase test system. 862.1440... Systems § 862.1440 Lactate dehydrogenase test system. (a) Identification. A lactate dehydrogenase test system is a device intended to measure the activity of the enzyme lactate dehydrogenase in serum....

  10. 21 CFR 862.1440 - Lactate dehydrogenase test system.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Lactate dehydrogenase test system. 862.1440... Systems § 862.1440 Lactate dehydrogenase test system. (a) Identification. A lactate dehydrogenase test system is a device intended to measure the activity of the enzyme lactate dehydrogenase in serum....

  11. 21 CFR 862.1445 - Lactate dehydrogenase isoenzymes test system.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Lactate dehydrogenase isoenzymes test system. 862... Test Systems § 862.1445 Lactate dehydrogenase isoenzymes test system. (a) Identification. A lactate dehydrogenase isoenzymes test system is a device intended to measure the activity of lactate...

  12. 21 CFR 862.1445 - Lactate dehydrogenase isoenzymes test system.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Lactate dehydrogenase isoenzymes test system. 862... Test Systems § 862.1445 Lactate dehydrogenase isoenzymes test system. (a) Identification. A lactate dehydrogenase isoenzymes test system is a device intended to measure the activity of lactate...

  13. 21 CFR 862.1445 - Lactate dehydrogenase isoenzymes test system.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Lactate dehydrogenase isoenzymes test system. 862... Test Systems § 862.1445 Lactate dehydrogenase isoenzymes test system. (a) Identification. A lactate dehydrogenase isoenzymes test system is a device intended to measure the activity of lactate...

  14. 21 CFR 862.1445 - Lactate dehydrogenase isoenzymes test system.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... dehydrogenase isoenzymes test system is a device intended to measure the activity of lactate dehydrogenase isoenzymes (a group of enzymes with similar biological activity) in serum. Measurements of...

  15. Genetics Home Reference: lactate dehydrogenase deficiency

    MedlinePlus

    ... throughout the body and is important for creating energy for cells. There are five different forms of this enzyme, each made up of four ... and lactate dehydrogenase-B subunits make up the different forms of the ... large amounts of energy during high-intensity physical activity when the body's ...

  16. Peafowl lactate dehydrogenase: problem of isoenzyme identification.

    PubMed

    Rose, R G; Wilson, A C

    1966-09-16

    Peafowl, like other vertebrates, contain multiple forms of lactate dehydrogenase. The electrophoretic properties of the peafowl isoenzymes are unusual in that the isoenzyme from heart tissue can be either more or less anodic than that of muscle, depending on the pH. This finding focuses attention on the problem of isoenzyme identification. It is suggested that isoenzymes be identified on the basis of properties that are chemically and biologically more significant than electrophoretic mobility. PMID:5917779

  17. Presence of lactate dehydrogenase and lactate racemase in Megasphaera elsdenii grown on glucose or lactate.

    PubMed Central

    Hino, T; Kuroda, S

    1993-01-01

    Activity of D-lactate dehydrogenase (D-LDH) was shown not only in cell extracts from Megasphaera elsdenii grown on DL-lactate, but also in cell extracts from glucose-grown cells, although glucose-grown cells contained approximately half as much D-LDH as DL-lactate-grown cells. This indicates that the D-LDH of M. elsdenii is a constitutive enzyme. However, lactate racemase (LR) activity was present in DL-lactate-grown cells, but was not detected in glucose-grown cells, suggesting that LR is induced by lactate. Acetate, propionate, and butyrate were produced similarly from both D- and L-lactate, indicating that LR can be induced by both D- and L-lactate. These results suggest that the primary reason for the inability of M. elsdenii to produce propionate from glucose is that cells fermenting glucose do not synthesize LR, which is induced by lactate. PMID:8439152

  18. Catecholamine regulation of lactate dehydrogenase in rat brain cell culture

    SciTech Connect

    Kumar, S.; McGinnis, J.F.; de Vellis, J.

    1980-03-25

    The mechanism of catecholamine induction of the soluble cytoplasmic enzyme lactate dehydrogenase (EC 1.1.1.27) was studied in the rat glial tumor cell line, C6. Lactate dehydrogenase was partially purified from extracts of (/sup 3/H)leucine-labeled cells by affinity gel chromatography and quantitatively immunoprecipitated with anti-lactate dehydrogenase-5 IgG and with antilactate dehydrogenase-1 IgG. The immunoprecipitates were dissociated and electrophoresed on sodium dodecyl sulfate polyacrylamide gels. Using this methodology, the increased enzyme activity of lactate dehydrogenase in norepinephrine-treated C6 cells was observed to be concomitant with the increased synthesis of enzyme molecules. Despite the continued presence of norepinephrine, the specific increase in the rate of synthesis of lactate dehydrogenase was transient. It was first detected at 4 h, was maximum at 9 h, and returned to basal levels by 24 h. The half-life of lactate dehydrogenase enzyme activity was 36 h during the induction and 40 h during deinduction. The half-life for decay of /sup 3/H-labeled lactate dehydrogenase was 41 h. These observations suggest that the increase in lactate dehydrogenase activity in norepinephrine-treated cells does not involve any change in the rate of degradation. Norepinephrine increased the specific rate of synthesis of both lactate dehydrogenase-5 (a tetramer of four M subunits) and lactate dehydrogenase-1 (a tetramer of four H subunits), although to different extents. Since these subunits are coded for by two separate genes on separate chromosomes, it suggests that the regulatory mechanism involves at least two separate sites of action.

  19. 21 CFR 862.1440 - Lactate dehydrogenase test system.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Lactate dehydrogenase test system. 862.1440 Section 862.1440 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES CLINICAL CHEMISTRY AND CLINICAL TOXICOLOGY DEVICES Clinical Chemistry Test Systems § 862.1440 Lactate dehydrogenase...

  20. Biochemical and structural characterization of Cryptosporidium parvum Lactate dehydrogenase.

    PubMed

    Cook, William J; Senkovich, Olga; Hernandez, Agustin; Speed, Haley; Chattopadhyay, Debasish

    2015-03-01

    The protozoan parasite Cryptosporidium parvum causes waterborne diseases worldwide. There is no effective therapy for C. parvum infection. The parasite depends mainly on glycolysis for energy production. Lactate dehydrogenase is a major regulator of glycolysis. This paper describes the biochemical characterization of C. parvum lactate dehydrogenase and high resolution crystal structures of the apo-enzyme and four ternary complexes. The ternary complexes capture the enzyme bound to NAD/NADH or its 3-acetylpyridine analog in the cofactor binding pocket, while the substrate binding site is occupied by one of the following ligands: lactate, pyruvate or oxamate. The results reveal distinctive features of the parasitic enzyme. For example, C. parvum lactate dehydrogenase prefers the acetylpyridine analog of NADH as a cofactor. Moreover, it is slightly less sensitive to gossypol inhibition compared with mammalian lactate dehydrogenases and not inhibited by excess pyruvate. The active site loop and the antigenic loop in C. parvum lactate dehydrogenase are considerably different from those in the human counterpart. Structural features and enzymatic properties of C. parvum lactate dehydrogenase are similar to enzymes from related parasites. Structural comparison with malate dehydrogenase supports a common ancestry for the two genes. PMID:25542170

  1. Serum lactate dehydrogenase activity in canine malignancies.

    PubMed

    Marconato, L; Crispino, G; Finotello, R; Mazzotti, S; Salerni, F; Zini, E

    2009-12-01

    Lactate dehydrogenase (LDH) is commonly used in human cancer patients for prognostic purposes. Aim of this study was to determine the magnitude of serum LDH elevation in dogs with cancer compared with healthy dogs and dogs with non-neoplastic disease, and to verify whether it may support the diagnosis of specific malignancies. About 128 healthy dogs, 211 diseased dogs and 188 cancer dogs were enrolled. Dogs with cancer had significantly higher LDH than diseased (P < 0.001) and healthy dogs (P < 0.001), but large overlap was found. Dogs with lymphoma showed significantly higher LDH compared with dogs with carcinoma (P < 0.001) or mast cell tumour (MCT; P < 0.05) but not compared with other malignancies. When considering lymphoma and MCT, LDH levels were not different between early and advanced clinical stages. Measuring LDH levels may not be useful as a screening tool for cancer detection. More studies are needed to define its role in specific tumours. PMID:19891694

  2. 21 CFR 862.1445 - Lactate dehydrogenase isoenzymes test system.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Lactate dehydrogenase isoenzymes test system. 862.1445 Section 862.1445 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES CLINICAL CHEMISTRY AND CLINICAL TOXICOLOGY DEVICES Clinical Chemistry Test Systems § 862.1445 Lactate...

  3. Creatine

    MedlinePlus

    ... for 5 days, may be more effective than continuous use. However, there is still some uncertainty about ... Early studies suggest taking creatine might produce small improvements in muscle strength in people with these conditions. ...

  4. Mutants of Escherichia coli deficient in the fermentative lactate dehydrogenase

    SciTech Connect

    Mat-Jan, F.; Alam, K.Y.; Clark, D.P. )

    1989-01-01

    Mutants of Escherichia coli deficient in the fermentative NAD-linked lactate dehydrogenase (ldh) have been isolated. These mutants showed no growth defects under anaerobic conditions unless present together with a defect in pyruvate formate lyase (pfl). Double mutants (pfl ldh) were unable to grow anaerobically on glucose or other sugars even when supplemented with acetate, whereas pfl mutants can do so. The ldh mutation was found to map at 30.5 min on the E. coli chromosome. The ldh mutant FMJ39 showed no detectable lactate dehydrogenase activity and produced no lactic acid from glucose under anaerobic conditions as estimated by in vivo nuclear magnetic resonance measurements. We also found that in wild-type strains the fermentative lactate dehydrogenase was conjointly induced by anaerobic conditions and an acidic pH. Despite previous findings that phosphate concentrations affect the proportion of lactic acid produced during fermentation, we were unable to find any intrinsic effect of phosphate on lactate dehydrogenase activity, apart from the buffering effect of this ion.

  5. Evolution of D-lactate dehydrogenase activity from glycerol dehydrogenase and its utility for D-lactate production from lignocellulose.

    PubMed

    Wang, Qingzhao; Ingram, Lonnie O; Shanmugam, K T

    2011-11-22

    Lactic acid, an attractive, renewable chemical for production of biobased plastics (polylactic acid, PLA), is currently commercially produced from food-based sources of sugar. Pure optical isomers of lactate needed for PLA are typically produced by microbial fermentation of sugars at temperatures below 40 °C. Bacillus coagulans produces L(+)-lactate as a primary fermentation product and grows optimally at 50 °C and pH 5, conditions that are optimal for activity of commercial fungal cellulases. This strain was engineered to produce D(-)-lactate by deleting the native ldh (L-lactate dehydrogenase) and alsS (acetolactate synthase) genes to impede anaerobic growth, followed by growth-based selection to isolate suppressor mutants that restored growth. One of these, strain QZ19, produced about 90 g L(-1) of optically pure D(-)-lactic acid from glucose in < 48 h. The new source of D-lactate dehydrogenase (D-LDH) activity was identified as a mutated form of glycerol dehydrogenase (GlyDH; D121N and F245S) that was produced at high levels as a result of a third mutation (insertion sequence). Although the native GlyDH had no detectable activity with pyruvate, the mutated GlyDH had a D-LDH specific activity of 0.8 μmoles min(-1) (mg protein)(-1). By using QZ19 for simultaneous saccharification and fermentation of cellulose to D-lactate (50 °C and pH 5.0), the cellulase usage could be reduced to 1/3 that required for equivalent fermentations by mesophilic lactic acid bacteria. Together, the native B. coagulans and the QZ19 derivative can be used to produce either L(+) or D(-) optical isomers of lactic acid (respectively) at high titers and yields from nonfood carbohydrates. PMID:22065761

  6. Evolution of D-lactate dehydrogenase activity from glycerol dehydrogenase and its utility for D-lactate production from lignocellulose

    PubMed Central

    Wang, Qingzhao; Ingram, Lonnie O.; Shanmugam, K. T.

    2011-01-01

    Lactic acid, an attractive, renewable chemical for production of biobased plastics (polylactic acid, PLA), is currently commercially produced from food-based sources of sugar. Pure optical isomers of lactate needed for PLA are typically produced by microbial fermentation of sugars at temperatures below 40 °C. Bacillus coagulans produces L(+)-lactate as a primary fermentation product and grows optimally at 50 °C and pH 5, conditions that are optimal for activity of commercial fungal cellulases. This strain was engineered to produce D(−)-lactate by deleting the native ldh (L-lactate dehydrogenase) and alsS (acetolactate synthase) genes to impede anaerobic growth, followed by growth-based selection to isolate suppressor mutants that restored growth. One of these, strain QZ19, produced about 90 g L-1 of optically pure D(−)-lactic acid from glucose in < 48 h. The new source of D-lactate dehydrogenase (D-LDH) activity was identified as a mutated form of glycerol dehydrogenase (GlyDH; D121N and F245S) that was produced at high levels as a result of a third mutation (insertion sequence). Although the native GlyDH had no detectable activity with pyruvate, the mutated GlyDH had a D-LDH specific activity of 0.8 μmoles min-1 (mg protein)-1. By using QZ19 for simultaneous saccharification and fermentation of cellulose to D-lactate (50 °C and pH 5.0), the cellulase usage could be reduced to 1/3 that required for equivalent fermentations by mesophilic lactic acid bacteria. Together, the native B. coagulans and the QZ19 derivative can be used to produce either L(+) or D(−) optical isomers of lactic acid (respectively) at high titers and yields from nonfood carbohydrates. PMID:22065761

  7. NADP+-Preferring d-Lactate Dehydrogenase from Sporolactobacillus inulinus

    PubMed Central

    Zhu, Lingfeng; Xu, Xiaoling; Wang, Limin; Ma, Yanhe

    2015-01-01

    Hydroxy acid dehydrogenases, including l- and d-lactate dehydrogenases (L-LDH and D-LDH), are responsible for the stereospecific conversion of 2-keto acids to 2-hydroxyacids and extensively used in a wide range of biotechnological applications. A common feature of LDHs is their high specificity for NAD+ as a cofactor. An LDH that could effectively use NADPH as a coenzyme could be an alternative enzymatic system for regeneration of the oxidized, phosphorylated cofactor. In this study, a d-lactate dehydrogenase from a Sporolactobacillus inulinus strain was found to use both NADH and NADPH with high efficiencies and with a preference for NADPH as its coenzyme, which is different from the coenzyme utilization of all previously reported LDHs. The biochemical properties of the D-LDH enzyme were determined by X-ray crystal structural characterization and in vivo and in vitro enzymatic activity analyses. The residue Asn174 was demonstrated to be critical for NADPH utilization. Characterization of the biochemical properties of this enzyme will contribute to understanding of the catalytic mechanism and provide referential information for shifting the coenzyme utilization specificity of 2-hydroxyacid dehydrogenases. PMID:26150461

  8. POSTNATAL EFFECTS OF HEXACHLOROBENZENE (HCB) ON CARDIAC LACTIC DEHYDROGENASE (LDH) AND CREATINE KINASE (CK) ISOZYMES IN CD-1 MICE

    EPA Science Inventory

    Pregnant CD-1 mice were treated with hexachlorobenzene (HCB) by gavage at doses of 0, 1, 10 and 50 mg HCB/kg body weight on days 6-17 of gestation and studied on day 1 or 21 postpartum (pp). Hearts of the dams and pups were assayed for lactic dehydrogenase (LDH) and creatine kina...

  9. Uncommon serum creatine phosphokinase and lactic dehydrogenase increase during diosmin therapy: two case reports

    PubMed Central

    2014-01-01

    Introduction Short-term administration of diosmin is usually considered safe, with only minor side effects (stomach and abdominal pain, diarrhea, dermatological disorders, and headache) occasionally observed. Within a 4-year period, a general practitioner noticed 17 cases of mild, diosmin-induced side effects, two of which showed particular interest. Cases presentation Case 1: A 55-year-old Caucasian woman presented with chronic leg venous insufficiency. She was prescribed diosmin 450mg twice a day. After 5 days of therapy, she developed pain in the legs (myalgia), and diosmin therapy was suspended. She made a spontaneous attempt of drug rechallenge and her leg pain reappeared. Thus, she underwent blood analysis, which showed elevation of creatine phosphokinase levels. Creatine phosphokinase values normalized only after prolonged discontinuation of the therapy. Case 2: A 79-year-old Caucasian man, who was diagnosed with acute hemorrhoidal syndrome. After 21 days of continuous diosmin treatment, increased levels of serum lactic dehydrogenase were detected. In both cases a comprehensive analysis of all possible causes for enzyme elevation was made. Conclusions A feasible hypothesis to explain these rare effects could be that exaggerated adrenergic activity occurred on microcirculation, leading to an excessive peripheral vasoconstriction and subsequent ischemic damage. An individual predisposition is strongly suggested. A concurrence of events was probably responsible for the elevation of nonspecific tissue necrosis markers. Physicians and patients must be aware of these rare, but possible, adverse drug reactions. PMID:24934505

  10. Isotope effects on binding of NAD+ to lactate dehydrogenase

    SciTech Connect

    LaReau, R.D.; Wan, W.; Anderson, V.E.

    1989-04-18

    The isotope effect on binding (4-/sup 2/H)NAD+ and (4-/sup 3/H)NAD+ to lactate dehydrogenase has been shown to be 1.10 +/- 0.03 by whole molecule isotope ratio mass spectrometry and 1.085 +/- 0.01 by /sup 3/H//sup 14/C scintillation counting. These values demonstrate that specific interactions of the nicotinamide ring with the enzyme make the C-H bond at C-4 less stiff in the binary complex.

  11. Accelerated Lactate Dehydrogenase Activity Potentiates Osteoclastogenesis via NFATc1 Signaling

    PubMed Central

    Kim, Jin Man; Kwon, So Hyun; Lee, Seoung Hoon; Lee, Soo Young; Jeong, Daewon

    2016-01-01

    Osteoclasts seem to be metabolic active during their differentiation and bone-resorptive activation. However, the functional role of lactate dehydrogenase (LDH), a tetrameric enzyme consisting of an A and/or B subunit that catalyzes interconversion of pyruvate to lactate, in RANKL-induced osteoclast differentiation is not known. In this study, RANKL treatment induced gradual gene expression and activation of the LDH A2B2 isotype during osteoclast differentiation as well as the LDH A1B3 and B4 isotypes during osteoclast maturation after pre-osteoclast formation. Glucose consumption and lactate production in growth media were accelerated during osteoclast differentiation, together with enhanced expression of H+-lactate co-transporter and increased extracellular acidification, demonstrating that glycolytic metabolism was stimulated during differentiation. Further, oxygen consumption via mitochondria was stimulated during osteoclast differentiation. On the contrary, depletion of LDH-A or LDH-B subunit suppressed both glycolytic and mitochondrial metabolism, resulting in reduced mature osteoclast formation via decreased osteoclast precursor fusion and down-regulation of the osteoclastogenic critical transcription factor NFATc1 and its target genes. Collectively, our findings suggest that RANKL-induced LDH activation stimulates glycolytic and mitochondrial respiratory metabolism, facilitating mature osteoclast formation via osteoclast precursor fusion and NFATc1 signaling. PMID:27077737

  12. Lactate Dehydrogenase Catalysis: Roles of Keto, Hydrated, and Enol Pyruvate

    NASA Astrophysics Data System (ADS)

    Meany, J. E.

    2007-09-01

    Many carbonyl substrates of oxidoreductase enzymes undergo hydration and enolization so that these substrate systems are partitioned between keto, hydrated (gem-diol), and enol forms in aqueous solution. Some oxidoreductase enzymes are subject to inhibition by high concentrations of substrate. For such enzymes, two questions arise pertaining to enzyme "substrate" interactions: (i) which form of the substrate system serves as the preferential substrate and (ii) which form acts to inhibit the enzyme? Thus the relative concentrations of the forms of these substrate systems (keto, hydrated, enol) may provide a form of metabolic control. In this light, the present article considers the reduction of pyruvate by lactate dehydrogenase in the presence of NADH. This reaction is inhibited by relatively high concentrations of pyruvate and the physiological significance of this inhibition has been a subject of controversy for many years. Summarized in this article are data from the literature pertaining to the interactions of keto, hydrated, and enol pyruvate with lactate dehydrogenase. Biochemistry instructors and their students are invited to review such pertinent articles so that they also may evaluate the possibility that the "substrate" inhibition of the isoenzymes in the heart muscle may be, under certain conditions, relevant as a form of metabolic control.

  13. Yeast cell-based analysis of human lactate dehydrogenase isoforms.

    PubMed

    Mohamed, Lulu Ahmed; Tachikawa, Hiroyuki; Gao, Xiao-Dong; Nakanishi, Hideki

    2015-12-01

    Human lactate dehydrogenase (LDH) has attracted attention as a potential target for cancer therapy and contraception. In this study, we reconstituted human lactic acid fermentation in Saccharomyces cerevisiae, with the goal of constructing a yeast cell-based LDH assay system. pdc null mutant yeast (mutated in the endogenous pyruvate decarboxylase genes) are unable to perform alcoholic fermentation; when grown in the presence of an electron transport chain inhibitor, pdc null strains exhibit a growth defect. We found that introduction of the human gene encoding LDHA complemented the pdc growth defect; this complementation depended on LDHA catalytic activity. Similarly, introduction of the human LDHC complemented the pdc growth defect, even though LDHC did not generate lactate at the levels seen with LDHA. In contrast, the human LDHB did not complement the yeast pdc null mutant, although LDHB did generate lactate in yeast cells. Expression of LDHB as a red fluorescent protein (RFP) fusion yielded blebs in yeast, whereas LDHA-RFP and LDHC-RFP fusion proteins exhibited cytosolic distribution. Thus, LDHB exhibits several unique features when expressed in yeast cells. Because yeast cells are amenable to genetic analysis and cell-based high-throughput screening, our pdc/LDH strains are expected to be of use for versatile analyses of human LDH. PMID:26126931

  14. Conformational heterogeneity within the Michaelis complex of lactate dehydrogenase.

    PubMed

    Deng, Hua; Vu, Dung V; Clinch, Keith; Desamero, Ruel; Dyer, R Brian; Callender, Robert

    2011-06-16

    A series of isotope edited IR measurements, both static as well as temperature jump relaxation spectroscopy, are performed on lactate dehydrogenase (LDH) to determine the ensemble of structures available to its Michaelis complex. There clearly has been a substantial reduction in the number of states available to the pyruvate substrate (as modeled by the substrate mimic, oxamate) and NADH when bound to protein compared to dissolved in solution, as determined by the bandwidths and positions of the critical C(2)?O band of the bound substrate mimic and the C(4)-H stretch of the NADH reduced nicotinamide group. Moreover, it is found that a strong ionic bond (characterized by a signature IR band discovered in this study) is formed between the carboxyl group of bound pyruvate with (presumably) Arg171, forming a strong "anchor" within the protein matrix. However, conformational heterogeneity within the Michaelis complex is found that has an impact on both catalytic efficiency and thermodynamics of the enzyme. PMID:21568287

  15. Human Lactate Dehydrogenase A Inhibitors: A Molecular Dynamics Investigation

    PubMed Central

    Shi, Yun; Pinto, B. Mario

    2014-01-01

    Lactate dehydrogenase A (LDHA) is an important enzyme in fermentative glycolysis, generating most energy for cancer cells that rely on anaerobic respiration even under normal oxygen concentrations. This renders LDHA a promising molecular target for the treatment of various cancers. Several efforts have been made recently to develop LDHA inhibitors with nanomolar inhibition and cellular activity, some of which have been studied in complex with the enzyme by X-ray crystallography. In this work, we present a molecular dynamics (MD) study of the binding interactions of selected ligands with human LDHA. Conventional MD simulations demonstrate different binding dynamics of inhibitors with similar binding affinities, whereas steered MD simulations yield discrimination of selected LDHA inhibitors with qualitative correlation between the in silico unbinding difficulty and the experimental binding strength. Further, our results have been used to clarify ambiguities in the binding modes of two well-known LDHA inhibitors. PMID:24466056

  16. Structure of the human lactate dehydrogenase B gene.

    PubMed Central

    Takeno, T; Li, S S

    1989-01-01

    Human genomic clones containing parts of the lactate dehydrogenase B (LDH-B) gene (approx. 25 kb in length) were isolated and characterized. The protein-coding sequence of human LDH-B gene is interrupted by six introns at codons nos. 42-43, 82, 140, 198, 237 and 278-279, and the positions of these introns are homologous to those of LDH-A genes from man and mouse. The 5' non-coding region of human LDH-B gene is interrupted by an intron six nucleotide residues upstream of the ATG translation-initiation site, whereas those of human and mouse LDH-A genes are interrupted at 24 nucleotide residues 5' to the ATG initiation codon. As is the case of LDH-A genes from man and mouse, there is no intron in the 3' non-coding region of human LDH-B gene. PMID:2930497

  17. Effect of selected alcohol dehydrogenase inhibitors on human hepatic lactate dehydrogenase activity - an in vitro study.

    PubMed

    Dudka, Jaroslaw; Burdan, Franciszek; Szumilo, Justyna; Tokarska, Edyta; Korobowicz, Agnieszka; Klepacz, Robert; Gieroba, Renata; Madej, Barbara; Korobowicz, Elzbieta

    2005-01-01

    Metabolic acidosis severely complicates methanol and ethylene glycol intoxications. Acidosis is caused by acid metabolites and can be intensified by lactate elevation. Lactate concentration depends on the NADH(2)/NAD ratio. Lactate dehydrogenase (LDH, E.C.1.1.1.27.) supplies more lactate when the level of NADH(2) is elevated. The aim of the study was to evaluate the effect of alcohol dehydrogenase (ADH) inhibitors and substrates: cimetidine, EDTA, 4-methylpyrazole (4-MP), Ukrain and ethanol on LDH activity. The activity of LDH was determined spectrophotometrically in human liver homogenates incubated with cimetidine, EDTA, 4-MP and Ukrain at concentrations of 2 x 10(-6), 10(-5) and 5 x 10(-5) m as well as ethanol at concentrations of 12.50, 25.00, 50.00 mm. The LDH activity was significantly increased by 10(-5) and 5 x 10(-5) m concentrations of cimetidine and 4-MP, and by all concentrations of ethanol. The most effective change of LDH activity of about 26% (P<0.01) was observed at the highest concentration of ethanol. Ukrain inhibited LDH activity at both concentrations, i.e. 10(-5) and 5 x 10(-5) m (P<0.05). However, EDTA did not significantly influence LDH activity. The data showed that ethanol and 4-MP, the main antidotes in methanol or ethylene glycol poisoning, may increase liver LDH activity - an undesirable effect during the therapy of patients intoxicated with these alcohols. On the other hand, the decrease of LDH activity in the presence of Ukrain is a promising finding but definitely requires further investigation. PMID:16208625

  18. Not only osmoprotectant: betaine increased lactate dehydrogenase activity and L-lactate production in lactobacilli.

    PubMed

    Zou, Huibin; Wu, Zaiqiang; Xian, Mo; Liu, Hui; Cheng, Tao; Cao, Yujin

    2013-11-01

    Lactobacilli are commonly used for industrial production of polymer-grade L-lactic acid. The present study tested the Tween 80 alternative betaine in L-lactate production by several industrial lactobacilli. In flask fermentation of Lactobacillus casei, Lactobacillus buchneri, Lactobacillus lactis and Lactobacillus rhamnosus, the betaine addition (2g/l) had similar osmoprotectant effect with Tween 80 but had increased the lactate dehydrogenase activities and L-lactate production than Tween 80 control. In fed-batch fermentation of L. casei, betaine supplementation improved the L-lactic acid titer to 190 g/l, the yield to 95.5% (g L-lactic acid/g glucose), the productivity to 2.6g/lh, and the optical purity to 97.0%. The results demonstrated that supplementation of Tween 80 alternative - betaine in the fermentation medium is feasible for industrial l-lactic acid fermentation by lactobacilli, which will improve the lactate production but will not increase the process costs and modify any process conditions. PMID:24035452

  19. Fabrication of lactate biosensor based on lactate dehydrogenase immobilized on cerium oxide nanoparticles.

    PubMed

    Nesakumar, Noel; Sethuraman, Swaminathan; Krishnan, Uma Maheswari; Rayappan, John Bosco Balaguru

    2013-11-15

    An electrochemical biosensor was developed to determine lactate that plays an important role in clinical diagnosis, fermentation and food quality analysis. Abnormal concentration of lactate has been related to diseases such as hypoxia, acute heart disorders, lactic acidosis, muscle fatigue and meningitis. Also, lactate concentration in blood helps to evaluate the athletic performance in sports. The main aim of the work is to fabricate NADH/LDH/Nano-CeO2/GCE bio-electrode for sensing lactate in human blood samples. Toward this, CeO2 nanoparticles were synthesized by a hydroxide mediated approach using cerium nitrate hexahydrate (Ce(NO3)3·6H2O) and NaOH as precursors. X-ray diffraction (XRD) and Field Emission Scanning Electron Microscopy (FE-SEM) studies were carried out to determine the structural and morphological characteristics of CeO2 nanoparticles. XRD pattern indicated the formation of highly crystalline CeO2 nanoparticles with face centered cubic structure. The FE-SEM studies revealed the formation of nanospherical particles of size 29.73±2.59 nm. The working electrode was fabricated by immobilizing nicotinamide adenine dinucleotide (NADH) and lactate dehydrogenase (LDH) on GCE surface with CeO2 nanoparticles as an interface. Electrochemical studies were carried out through cyclic voltammetry using a three electrode system with NADH/LDH/NanoCeO2/GCE as a working electrode, Ag/AgCl saturated with 0.1M KCl as a reference electrode and Pt wire as a counter electrode. From the amperometric study, the linearity was found to be in the range of 0.2-2 mM with the response time of less than 4s. PMID:24034216

  20. [Isozyme patterns of lactate dehydrogenase from tissues of mink and arctic fox during postnatal development].

    PubMed

    Tiutiunnik, N N; Kozhevnikova, L K; Unzhakov, A R; Meldo, Kh I

    2002-01-01

    Isozymes of lactate dehydrogenase extracted from heart, kidney, and liver of mink (Mustela vison Briss.) and Arctic fox (Alopex lagopus L.) during postnatal development were separated by agarose gel electrophoresis. Tissue-specific isozyme pattern of lactate dehydrogenase can be revealed at the age of one month, while the definitive pattern is formed at the age of four months. The isozyme patterns of lactate dehydrogenase in the studied tissues of mink and Arctic fox share the properties specific for animal species of various ecogenesis. PMID:12068724

  1. Production of L-lactate in Leuconostoc citreum via heterologous expression of L-lactate dehydrogenase gene.

    PubMed

    Jin, Qing; Jung, Jee Yun; Kim, Yu Jin; Eom, Hyun-Ju; Kim, So-Young; Kim, Tae-Jip; Han, Nam Soo

    2009-10-26

    D-form lactate is often found in fermented foods and excessive dietary intake of D-lactate may cause metabolic stress in both infants and patients. Leuconostoc citreum is a major lactic acid bacterium that produces D-lactate in fermented foods. The aim of this study was to change the pyruvate carbon flux in L. citreum from D-lactate into L-lactate by heterologous expression of L-lactate dehydrogenase (ldhL) gene. For this, ldhL from Lactobacillus plantarum was cloned and introduced into L. citreum using a shuttle vector pLeuCM. In the transformant, ldhL was successfully transcribed and L-lactate dehydrogenase was expressed. As a consequence of transformation, the ratio between D- and L-isomers was changed due to the increment of L-lactate and the decrement of D-lactate, but no significant differences were found in total lactate concentration between the host and transformant cells. This is the first report of metabolic engineering in Leuconostoc by modulating the central carbon flux into health-favored way. PMID:19699768

  2. Nuclear lactate dehydrogenase modulates histone modification in human hepatocytes

    SciTech Connect

    Castonguay, Zachary; Auger, Christopher; Thomas, Sean C.; Chahma, M’hamed; Appanna, Vasu D.

    2014-11-07

    Highlights: • Nuclear LDH is up-regulated under oxidative stress. • SIRT1 is co-immunoprecipitated bound to nuclear LDH. • Nuclear LDH is involved in histone deacetylation and epigenetics. - Abstract: It is becoming increasingly apparent that the nucleus harbors metabolic enzymes that affect genetic transforming events. Here, we describe a nuclear isoform of lactate dehydrogenase (nLDH) and its ability to orchestrate histone deacetylation by controlling the availability of nicotinamide adenine dinucleotide (NAD{sup +}), a key ingredient of the sirtuin-1 (SIRT1) deacetylase system. There was an increase in the expression of nLDH concomitant with the presence of hydrogen peroxide (H{sub 2}O{sub 2}) in the culture medium. Under oxidative stress, the NAD{sup +} generated by nLDH resulted in the enhanced deacetylation of histones compared to the control hepatocytes despite no discernable change in the levels of SIRT1. There appeared to be an intimate association between nLDH and SIRT1 as these two enzymes co-immunoprecipitated. The ability of nLDH to regulate epigenetic modifications by manipulating NAD{sup +} reveals an intricate link between metabolism and the processing of genetic information.

  3. SERUM VALUES OF ALKALINE PHOSPHATASE AND LACTATE DEHYDROGENASE IN OSTEOSARCOMA

    PubMed Central

    ZUMÁRRAGA, JUAN PABLO; BAPTISTA, ANDRÉ MATHIAS; ROSA, LUIS PABLO DE LA; CAIERO, MARCELO TADEU; CAMARGO, OLAVO PIRES DE

    2016-01-01

    ABSTRACT Objective: To study the relationship between the pre and post chemotherapy (CT) serum levels of alkaline phosphatase (AP) and lactate dehydrogenase (LDH), and the percentage of tumor necrosis (TN) found in specimens after the pre surgical CT in patients with osteosarcoma. Methods: Series of cases with retrospective evaluation of patients diagnosed with osteosarcoma. Participants were divided into two groups according to serum values of both enzymes. The values of AP and LDH were obtained before and after preoperative CT. The percentage of tumor necrosis (TN) of surgical specimens of each patient was also included. Results: One hundred and thirty seven medical records were included from 1990 to 2013. Both the AP as LDH decreased in the patients studied, being the higher in pre CT than post CT. The average LHD decrease was 795.12U/L and AP decrease was 437.40 U/L. The average TN was 34.10 %. There was no statistically significant correlation between the serums values and the percentage of tumoral necrosis. Conclusion: The serum levels values of AP and LDH are not good predictors for the chemotherapy-induced necrosis in patients with osteosarcoma. Level of Evidence IV, Case Series.

  4. Acetate Utilization in Lactococcus lactis Deficient in Lactate Dehydrogenase: a Rescue Pathway for Maintaining Redox Balance

    PubMed Central

    Hols, Pascal; Ramos, Ana; Hugenholtz, Jeroen; Delcour, Jean; de Vos, Willem M.; Santos, Helena; Kleerebezem, Michiel

    1999-01-01

    Acetate was shown to improve glucose fermentation in Lactococcus lactis deficient in lactate dehydrogenase. 13C and 1H nuclear magnetic resonance studies using [2-13C]glucose and [2-13C]acetate as substrates demonstrated that acetate was exclusively converted to ethanol. This novel pathway provides an alternative route for NAD+ regeneration in the absence of lactate dehydrogenase. PMID:10464231

  5. Decreasing lactate level and increasing antibody production in Chinese Hamster Ovary cells (CHO) by reducing the expression of lactate dehydrogenase and pyruvate dehydrogenase kinases.

    PubMed

    Zhou, Meixia; Crawford, Yongping; Ng, Domingos; Tung, Jack; Pynn, Abigail F J; Meier, Angela; Yuk, Inn H; Vijayasankaran, Natarajan; Leach, Kimberly; Joly, John; Snedecor, Bradley; Shen, Amy

    2011-04-20

    Large-scale fed-batch cell culture processes of CHO cells are the standard platform for the clinical and commercial production of monoclonal antibodies. Lactate is one of the major by-products of CHO fed-batch culture. In pH-controlled bioreactors, accumulation of high levels of lactate is accompanied by high osmolality due to the addition of base to control pH of the cell culture medium, potentially leading to lower cell growth and lower therapeutic protein production during manufacturing. Lactate dehydrogenase (LDH) is an enzyme that catalyzes the conversion of the substrate, pyruvate, into lactate and many factors including pyruvate concentration modulate LDH activity. Alternately, pyruvate can be converted to acetyl-CoA by pyruvate dehydrogenases (PDHs), to be metabolized in the TCA cycle. PDH activity is inhibited when phosphorylated by pyruvate dehydrogenase kinases (PDHKs). In this study, we knocked down the gene expression of lactate dehydrogenase A (LDHa) and PDHKs to investigate the effect on lactate metabolism and protein production. We found that LDHa and PDHKs can be successfully downregulated simultaneously using a single targeting vector carrying small inhibitory RNAs (siRNA) for LDHa and PDHKs. Moreover, our fed-batch shake flask evaluation data using siRNA-mediated LDHa/PDHKs knockdown clones showed that downregulating LDHa and PDHKs in CHO cells expressing a therapeutic monoclonal antibody reduced lactate production, increased specific productivity and volumetric antibody production by approximately 90%, 75% and 68%, respectively, without appreciable impact on cell growth. Similar trends of lower lactate level and higher antibody productivity on average in siRNA clones were also observed from evaluations performed in bioreactors. PMID:21392546

  6. Mitochondrial and plasma membrane lactate transporter and lactate dehydrogenase isoform expression in breast cancer cell lines

    PubMed Central

    Hussien, Rajaa

    2011-01-01

    We hypothesized that dysregulation of lactate/pyruvate (monocarboxylate) transporters (MCT) and lactate dehydrogenase (LDH) isoforms contribute to the Warburg effect in cancer. Therefore, we assayed for the expression levels and the localizations of MCT (1, 2, and 4), and LDH (A and B) isoforms in breast cancer cell lines MCF-7 and MDA-MB-231 and compared results with those from a control, untransformed primary breast cell line, HMEC 184. Remarkably, MCT1 is not expressed in MDA-MB-231, but MCT1 is expressed in MCF-7 cells, where its abundance is less than in control HMEC 184 cells. When present in HMEC 184 and MCF-7 cells, MCT1 is localized to the plasma membrane. MCT2 and MCT4 were expressed in all the cell lines studied. MCT4 expression was higher in MDA-MB-231 compared with MCF-7 and HMEC 184 cells, whereas MCT2 abundance was higher in MCF-7 compared with MDA-MB-231 and HMEC 184 cells. Unlike MCT1, MCT2 and MCT4 were localized in mitochondria in addition to the plasma membrane. LDHA and LDHB were expressed in all the cell-lines, but abundances were higher in the two cancer cell lines than in the control cells. MCF-7 cells expressed mainly LDHB, while MDA-MB-231 and control cells expressed mainly LDHA. LDH isoforms were localized in mitochondria in addition to the cytosol. These localization patterns were the same in cancerous and control cell lines. In conclusion, MCT and LDH isoforms have distinct expression patterns in two breast cancer cell lines. These differences may contribute to divergent lactate dynamics and oxidative capacities in these cells, and offer possibilities for targeting cancer cells. PMID:21177384

  7. Phylogenetic analysis of vertebrate lactate dehydrogenase (LDH) multigene families.

    PubMed

    Li, Yi-Ju; Tsoi, Stephen C-M; Mannen, Hideyuka; Shoei-lung Li, Steven

    2002-05-01

    In this paper we analyzed 49 lactate dehydrogenase (LDH) sequences, mostly from vertebrates. The amino acid sequence differences were found to be larger for a human-killifish pair than a human-lamprey pair. This indicates that some protein sequence convergence may occur and reduce the sequence differences in distantly related species. We also examined transitions and transversions separately for several species pairs and found that the transitions tend to be saturated in the distantly related species pair, while transversions are increasing. We conclude that transversions maintain a conservative rate through the evolutionary time. Kimura's two-parameter model for multiple-hit correction on transversions only was used to derive a distance measure and then construct a neighbor-joining (NJ) tree. Three findings were revealed from the NJ tree: (i) the branching order of the tree is consistent with the common branch pattern of major vertebrates; (ii) Ldh-A and Ldh-B genes were duplicated near the origin of vertebrates; and (iii) Ldh-C and Ldh-A in mammals were produced by an independent gene duplication in early mammalian history. Furthermore, a relative rate test showed that mammalian Ldh-C evolved more rapidly than mammalian Ldh-A. Under a two-rate model, this duplication event was calibrated to be approximately 247 million years ago (mya), dating back to the Triassic period. Other gene duplication events were also discovered in Xenopus, the first duplication occurring approximately 60-70 mya in both Ldh-A and Ldh-B, followed by another recent gene duplication event, approximately 20 mya, in Ldh-B. PMID:11965434

  8. Plasma Lactate Dehydrogenase Levels Predict Mortality in Acute Aortic Syndromes

    PubMed Central

    Morello, Fulvio; Ravetti, Anna; Nazerian, Peiman; Liedl, Giovanni; Veglio, Maria Grazia; Battista, Stefania; Vanni, Simone; Pivetta, Emanuele; Montrucchio, Giuseppe; Mengozzi, Giulio; Rinaldi, Mauro; Moiraghi, Corrado; Lupia, Enrico

    2016-01-01

    Abstract In acute aortic syndromes (AAS), organ malperfusion represents a key event impacting both on diagnosis and outcome. Increased levels of plasma lactate dehydrogenase (LDH), a biomarker of malperfusion, have been reported in AAS, but the performance of LDH for the diagnosis of AAS and the relation of LDH with outcome in AAS have not been evaluated so far. This was a bi-centric prospective diagnostic accuracy study and a cohort outcome study. From 2008 to 2014, patients from 2 Emergency Departments suspected of having AAS underwent LDH assay at presentation. A final diagnosis was obtained by aortic imaging. Patients diagnosed with AAS were followed-up for in-hospital mortality. One thousand five hundred seventy-eight consecutive patients were clinically eligible, and 999 patients were included in the study. The final diagnosis was AAS in 201 (20.1%) patients. Median LDH was 424 U/L (interquartile range [IQR] 367–557) in patients with AAS and 383 U/L (IQR 331–460) in patients with alternative diagnoses (P < 0.001). Using a cutoff of 450 U/L, the sensitivity of LDH for AAS was 44% (95% confidence interval [CI] 37–51) and the specificity was 73% (95% CI 69–76). Overall in-hospital mortality for AAS was 23.8%. Mortality was 32.6% in patients with LDH ≥ 450 U/L and 16.8% in patients with LDH < 450 U/L (P = 0.006). Following stratification according to LDH quartiles, in-hospital mortality was 12% in the first (lowest) quartile, 18.4% in the second quartile, 23.5% in the third quartile, and 38% in the fourth (highest) quartile (P = 0.01). LDH ≥ 450 U/L was further identified as an independent predictor of death in AAS both in univariate and in stepwise logistic regression analyses (odds ratio 2.28, 95% CI 1.11–4.66; P = 0.025), in addition to well-established risk markers such as advanced age and hypotension. Subgroup analysis showed excess mortality in association with LDH ≥ 450 U/L in elderly, hemodynamically stable and in nonsurgically treated patients. Plasma LDH constitutes a biomarker of poor outcome in patients with AAS. LDH is a rapid and universally available assay that could be used to improve risk stratification and to individualize treatment in patient groups where options are controversial. PMID:26871831

  9. NAD-Independent L-Lactate Dehydrogenase Is Required for L-Lactate Utilization in Pseudomonas stutzeri SDM

    PubMed Central

    Dou, Peipei; Ma, Cuiqing; Li, Lixiang; Kong, Jian; Xu, Ping

    2012-01-01

    Background Various Pseudomonas strains can use l-lactate as their sole carbon source for growth. However, the l-lactate-utilizing enzymes in Pseudomonas have never been identified and further studied. Methodology/Principal Findings An NAD-independent l-lactate dehydrogenase (l-iLDH) was purified from the membrane fraction of Pseudomonas stutzeri SDM. The enzyme catalyzes the oxidation of l-lactate to pyruvate by using FMN as cofactor. After cloning its encoding gene (lldD), l-iLDH was successfully expressed, purified from a recombinant Escherichia coli strain, and characterized. An lldD mutant of P. stutzeri SDM was constructed by gene knockout technology. This mutant was unable to grow on l-lactate, but retained the ability to grow on pyruvate. Conclusions/Significance It is proposed that l-iLDH plays an indispensable function in Pseudomonas l-lactate utilization by catalyzing the conversion of l-lactate into pyruvate. PMID:22574176

  10. Expression of Lactate Dehydrogenase in Aspergillus niger for L-Lactic Acid Production

    PubMed Central

    Dave, Khyati K.; Punekar, Narayan S.

    2015-01-01

    Different engineered organisms have been used to produce L-lactate. Poor yields of lactate at low pH and expensive downstream processing remain as bottlenecks. Aspergillus niger is a prolific citrate producer and a remarkably acid tolerant fungus. Neither a functional lactate dehydrogenase (LDH) from nor lactate production by A. niger is reported. Its genome was also investigated for the presence of a functional ldh. The endogenous A. niger citrate synthase promoter relevant to A. niger acidogenic metabolism was employed to drive constitutive expression of mouse lactate dehydrogenase (mldhA). An appraisal of different branches of the A. niger pyruvate node guided the choice of mldhA for heterologous expression. A high copy number transformant C12 strain, displaying highest LDH specific activity, was analyzed under different growth conditions. The C12 strain produced 7.7 g/l of extracellular L-lactate from 60 g/l of glucose, in non-neutralizing minimal media. Significantly, lactate and citrate accumulated under two different growth conditions. Already an established acidogenic platform, A. niger now promises to be a valuable host for lactate production. PMID:26683313

  11. INFLUENCE OF STEROID IMPLANTATION AND SUPPLEMENTATION ON PERFORMANCE AND LACTATE DEHYDROGENASE ACTIVITY IN STEERS GRAZING BERMUDAGRASS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Forty-five steers (BW = 246 5.4 kg) were randomly allocated to one of three paddocks of bermudagrass [Cynodon dactylon (L.) Pers] to determine the effects of timing of steroid implantation and supplementation on average daily gain and lactate dehydrogenase (LDH) activity. Steers received either n...

  12. Relationship of lactate dehydrogenase activity to body measurements of Angus x Charolais cows and calves

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Objectives were to examine 1) relationships between lactate dehydrogenase (LDH) activity and body measurements of grazing beef cows, and 2) the association between maternal LDH activity in late gestation and subsequent calf birth weight (BRW), hip height (HH) at weaning, and adjusted weaning weight ...

  13. Determination of lactate dehydrogenase activity and urea content in milk by dry chemistry.

    PubMed

    Lipperheide, C; Andersson, R; Petersen, B; Sommer, H

    1995-05-01

    Comparison of the new technique of dry chemistry (EKTACHEM 700-XR, Eastman Kodak Co., USA) with conventional wet chemistry (HITACHI 717, Boehringer Mannheim, Germany) for quantitations of lactate dehydrogenase activity and urea content in bovine milk resulted in correlation coefficients of more than 0.9 even when measuring fresh raw milk by dry chemistry. PMID:8578901

  14. Increasing the heme-dependent respiratory efficiency of Lactococcus lactis by inhibition of lactate dehydrogenase.

    PubMed

    Arioli, Stefania; Zambelli, Daniele; Guglielmetti, Simone; De Noni, Ivano; Pedersen, Martin B; Pedersen, Per Dedenroth; Dal Bello, Fabio; Mora, Diego

    2013-01-01

    The discovery of heme-induced respiration in Lactococcus lactis has radically improved the industrial processes used for the biomass production of this species. Here, we show that inhibition of the lactate dehydrogenase activity of L. lactis during growth under respiration-permissive conditions can stimulate aerobic respiration, thereby increasing not only growth efficiency but also the robustness of this organism. PMID:23064338

  15. Relationship of lactate dehydrogenase activity with body measeurements of Angus x Charolais cows and calves

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Angus x Charolais cows (n = 87) and their Angus-sired, spring-born calves (n = 86) were utilized to examine relationships between lactate dehydrogenase (LDH) activity and body measurements of beef cows; and the relationship between maternal LDH activity in late gestation and subsequent calf birth we...

  16. Modification of Rhizopus lactate dehydrogenase for improved resistance to fructose 1,6-bisphosphate

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Rhizopus oryzae is frequently used for fermentative production of lactic acid. We determined that one of the key enzymes, lactate dehydrogenase (LDH), involved in synthesis of lactic acid by R. oryzae was significantly inhibited by fructose 1,6-bisphosphate (FBP) at physiological concentrations. Thi...

  17. Influence of pH on the allosteric properties of lactate dehydrogenase activity of Phycomyces blakesleeanus.

    PubMed Central

    De Arriaga, D; Soler, J; Cadenas, E

    1982-01-01

    1. Lactate dehydrogenase from mycelium of Phycomyces blakesleeanus showed positive homotropic interactions with NADH at all pH values studied (pH 5.0-7.7). The calculated values for the first and last intrinsic association constants remained unaltered with pH, in contrast with the Hill coefficient value, which varied significantly, reaching its maximum values at pH 6.0 and 7.7. This suggests the hypothesis that pH regulates these homotropic effects by changes in the value of the intermediate intrinsic association constants. 2. From pH 7.2 to 7.7 lactate dehydrogenase exhibited, likewise, positive homotropic interactions with pyruvate. There were practically no changes in the first and last intrinsic association constants and in Hill coefficient values with pH. At pH values below 7.2 (pH 5.0-6.8) the enzyme showed high substrate inhibition, which was highly dependent on pH, NADH concentration and temperature. By way of substrate inhibition pH regulates, primarily, lactate dehydrogenase activity towards pyruvate, since the homotropic effects appear not to be dependent on pH. 3. Fructose 1,6-bisphosphate is a true allosteric effector of lactate dehydrogenase of Phycomyces blakesleeanus. it decreases positive co-operativity with NADH, and on the other hand pyruvate co-operativity turns into mixed co-operativity. In addition, the effector decreases the inhibitory effect caused by pyruvate. PMID:7115294

  18. LACTIC ACID PRODUCTION BY SACCHAROMYCES CEREVISIAE EXPRESSING A RHIZOPUS ORYZAE LACTATE DEHYDROGENASE GENE

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This work demonstrates the first example of a fungal LDH expressed in yeast. A L(+)-lactate dehydrogenase gene, ldhA, from the filamentous fungus Rhizopus oryzae was modified to be expressed under control of the Saccharomyces cerevisiae adhl promoter and terminator, then placed in a 2 micron contai...

  19. Assessment of freshness and freeze-thawing of sea bream fillets (Sparus aurata) by a cytosolic enzyme: Lactate dehydrogenase.

    PubMed

    Diop, Mamadou; Watier, Denis; Masson, Pierre-Yves; Diouf, Amadou; Amara, Rachid; Grard, Thierry; Lencel, Philippe

    2016-11-01

    The evaluation of freshness and freeze-thawing of fish fillets was carried out by assessment of autolysis of cells using a cytosolic enzyme lactate dehydrogenase. Autolysis plays an important role in spoilage of fish and postmortem changes in fish tissue are due to the breakdown of the cellular structures and release of cytoplasmic contents. The outflow of a cytosolic enzyme, lactate dehydrogenase, was studied in sea bream fillets and the Sparus aurata fibroblasts (SAF-1) cell-line during an 8day storage period at +4°C. A significant increase of lactate dehydrogenase release was observed, especially after 5days of storage. The ratio between the free and the total lactate dehydrogenase activity is a promising predictive marker to measure the quality of fresh fish fillets. The effect of freeze-thawing on cytosolic lactate dehydrogenase and lysosomal α-d-glucosidase activities was also tested. Despite the protecting effect of the tissue compared to the cell-line, a loss of lactate dehydrogenase activity, but not of α-d-glucosidase, was observed. In conclusion, lactate dehydrogenase may be used as a marker to both assess freshness of fish and distinguish between fresh and frozen-thawed fish fillets. PMID:27211667

  20. NAD-dependent lactate dehydrogenase catalyses the first step in respiratory utilization of lactate by Lactococcus lactis☆

    PubMed Central

    Zhao, Rui; Zheng, Sui; Duan, Cuicui; Liu, Fei; Yang, Lijie; Huo, Guicheng

    2013-01-01

    Lactococcus lactis can undergo respiration when hemin is added to an aerobic culture. The most distinctive feature of lactococcal respiration is that lactate could be consumed in the stationary phase concomitantly with the rapid accumulation of diacetyl and acetoin. However, the enzyme responsible for lactate utilization in this process has not yet been identified. As genes for fermentative NAD-dependent l-lactate dehydrogenase (l-nLDH) and potential electron transport chain (ETC)-related NAD-independent l-LDH (l-iLDH) exist in L. lactis, the activities of these enzymes were measured in this study using crude cell extracts prepared from respiratory and fermentation cultures. Further studies were conducted with purified preparations of recombinant LDH homologous proteins. The results showed that l-iLDH activity was hardly detected in both crude cell extracts and purified l-iLDH homologous protein while l-nLDH activity was very significant. This suggested that l-iLDHs were inactive in lactate utilization. The results of kinetic analyses and the effects of activator, inhibitor, substrate and product concentrations on the reaction equilibrium showed that l-nLDH was much more prone to catalyze the pyruvate reduction reaction but could reverse its role provided that the concentrations of NADH and pyruvate were extremely low while NAD and lactate were abundant. Metabolite analysis in respiratory culture revealed that the cellular status in the stationary phase was beneficial for l-nLDH to catalyze lactate oxidation. The factors accounting for the respiration- and stationary phase-dependent lactate utilization in L. lactis are discussed here. PMID:24251099

  1. Enzymatic Kinetic Properties of the Lactate Dehydrogenase Isoenzyme C4 of the Plateau Pika (Ochotona curzoniae)

    PubMed Central

    Wang, Yang; Wei, Lian; Wei, Dengbang; Li, Xiao; Xu, Lina; Wei, Linna

    2016-01-01

    Testis-specific lactate dehydrogenase (LDH-C4) is one of the lactate dehydrogenase (LDH) isozymes that catalyze the terminal reaction of pyruvate to lactate in the glycolytic pathway. LDH-C4 in mammals was previously thought to be expressed only in spermatozoa and testis and not in other tissues. Plateau pika (Ochotona curzoniae) belongs to the genus Ochotona of the Ochotonidea family. It is a hypoxia-tolerant species living in remote mountain areas at altitudes of 3000–5000 m above sea level on the Qinghai-Tibet Plateau. Surprisingly, Ldh-c is expressed not only in its testis and sperm, but also in somatic tissues of plateau pika. To shed light on the function of LDH-C4 in somatic cells, Ldh-a, Ldh-b, and Ldh-c of plateau pika were subcloned into bacterial expression vectors. The pure enzymes of Lactate Dehydrogenase A4 (LDH-A4), Lactate Dehydrogenase B4 (LDH-B4), and LDH-C4 were prepared by a series of expression and purification processes, and the three enzymes were identified by the method of sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) and native polyacrylamide gel electrophoresis (PAGE). The enzymatic kinetics properties of these enzymes were studied by Lineweaver-Burk double-reciprocal plots. The results showed the Michaelis constant (Km) of LDH-C4 for pyruvate and lactate was 0.052 and 4.934 mmol/L, respectively, with an approximate 90 times higher affinity of LDH-C4 for pyruvate than for lactate. At relatively high concentrations of lactate, the inhibition constant (Ki) of the LDH isoenzymes varied: LDH-A4 (Ki = 26.900 mmol/L), LDH-B4 (Ki = 23.800 mmol/L), and LDH-C4 (Ki = 65.500 mmol/L). These data suggest that inhibition of lactate by LDH-A4 and LDH-B4 were stronger than LDH-C4. In light of the enzymatic kinetics properties, we suggest that the plateau pika can reduce reliance on oxygen supply and enhance its adaptation to the hypoxic environments due to increased anaerobic glycolysis by LDH-C4. PMID:26751442

  2. Enzymatic Kinetic Properties of the Lactate Dehydrogenase Isoenzyme C₄ of the Plateau Pika (Ochotona curzoniae).

    PubMed

    Wang, Yang; Wei, Lian; Wei, Dengbang; Li, Xiao; Xu, Lina; Wei, Linna

    2016-01-01

    Testis-specific lactate dehydrogenase (LDH-C₄) is one of the lactate dehydrogenase (LDH) isozymes that catalyze the terminal reaction of pyruvate to lactate in the glycolytic pathway. LDH-C₄ in mammals was previously thought to be expressed only in spermatozoa and testis and not in other tissues. Plateau pika (Ochotona curzoniae) belongs to the genus Ochotona of the Ochotonidea family. It is a hypoxia-tolerant species living in remote mountain areas at altitudes of 3000-5000 m above sea level on the Qinghai-Tibet Plateau. Surprisingly, Ldh-c is expressed not only in its testis and sperm, but also in somatic tissues of plateau pika. To shed light on the function of LDH-C₄ in somatic cells, Ldh-a, Ldh-b, and Ldh-c of plateau pika were subcloned into bacterial expression vectors. The pure enzymes of Lactate Dehydrogenase A₄ (LDH-A₄), Lactate Dehydrogenase B₄ (LDH-B₄), and LDH-C₄ were prepared by a series of expression and purification processes, and the three enzymes were identified by the method of sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) and native polyacrylamide gel electrophoresis (PAGE). The enzymatic kinetics properties of these enzymes were studied by Lineweaver-Burk double-reciprocal plots. The results showed the Michaelis constant (Km) of LDH-C₄ for pyruvate and lactate was 0.052 and 4.934 mmol/L, respectively, with an approximate 90 times higher affinity of LDH-C₄ for pyruvate than for lactate. At relatively high concentrations of lactate, the inhibition constant (Ki) of the LDH isoenzymes varied: LDH-A₄ (Ki = 26.900 mmol/L), LDH-B₄ (Ki = 23.800 mmol/L), and LDH-C₄ (Ki = 65.500 mmol/L). These data suggest that inhibition of lactate by LDH-A₄ and LDH-B₄ were stronger than LDH-C₄. In light of the enzymatic kinetics properties, we suggest that the plateau pika can reduce reliance on oxygen supply and enhance its adaptation to the hypoxic environments due to increased anaerobic glycolysis by LDH-C₄. PMID:26751442

  3. Effect of a Marathon Run on Serum Lipoproteins, Creatine Kinase, and Lactate Dehydrogenase in Recreational Runners

    ERIC Educational Resources Information Center

    Kobayashi, Yoshio; Takeuchi, Toshiko; Hosoi, Teruo; Yoshizaki, Hidekiyo; Loeppky, Jack A.

    2005-01-01

    The objective of this study was to determine the effect of a marathon run on serum lipid and lipoprotein concentrations and serum muscle enzyme activities and follow their recovery after the run. These blood concentrations were measured before, immediately after, and serially after a marathon run in 15 male recreational runners. The triglyceride

  4. Effect of a Marathon Run on Serum Lipoproteins, Creatine Kinase, and Lactate Dehydrogenase in Recreational Runners

    ERIC Educational Resources Information Center

    Kobayashi, Yoshio; Takeuchi, Toshiko; Hosoi, Teruo; Yoshizaki, Hidekiyo; Loeppky, Jack A.

    2005-01-01

    The objective of this study was to determine the effect of a marathon run on serum lipid and lipoprotein concentrations and serum muscle enzyme activities and follow their recovery after the run. These blood concentrations were measured before, immediately after, and serially after a marathon run in 15 male recreational runners. The triglyceride…

  5. Control of Lactate Dehydrogenase, Lactate Glycolysis, and α-Amylase by O2 Deficit in Barley Aleurone Layers 1

    PubMed Central

    Hanson, Andrew D.; Jacobsen, John V.

    1984-01-01

    After 4 days in an atmosphere of N2, aleurone layers of barley (Hordeum vulgare L. cv Himalaya) remained viable as judged by their ability to produce near normal amounts of α-amylases when incubated with gibberellic acid (GA3) in air. However, layers did not produce α-amylase when GA3 was supplied under N2, apparently because α-amylase mRNA failed to accumulate. When an 8-hour pulse of [U-14C]glucose was supplied under N2 to freshly prepared aleurone layers, both [14C]lactate and [14C]ethanol accumulated; the [14C]lactate/[14C]ethanol ratio was about 0.3. Prior incubation of layers for 1 day under N2 changed this ratio to about 0.8, indicating an increase in the relative importance of the lactate branch of glycolysis. l(+)Lactate dehydrogenase (LDH) activity was low in freshly prepared aleurone layers and increased 10-fold during 2 days under N2, whereas alcohol dehydrogenase activity (ADH) was high initially and rose by 60%. The responses of LDH and ADH activities to O2 tension were dissimilar; when layers were incubated in various O2/N2 mixtures, LDH activity peaked at 2 to 5% O2 whereas ADH activity was highest at 0% O2. The LDH activity was resolved into several enzymically active bands by native polyacrylamide gel electrophoresis. We conclude that barley aleurone layers are highly adapted to O2 deficiency, that they possess an inducible LDH system as well as an ADH system, and we infer that the LDH and ADH systems are independently regulated. Images Fig. 2 Fig. 5 PMID:16663667

  6. Characterization of lactate dehydrogenase enzyme in seminal plasma of Japanese quail (Coturnix coturnix japonica).

    PubMed

    Singh, R P; Sastry, K V H; Pandey, N K; Shit, N; Agrawal, R; Singh, K B; Mohan, Jag; Saxena, V K; Moudgal, R P

    2011-02-01

    Lactate dehydrogenase enzyme present in quail seminal plasma has been characterized. Polyacrylamide gel electrophoresis and subsequently with LDH specific staining of seminal plasma revealed a single isozyme in quail semen. Studies on substrate inhibition, pH for optimum activity and inhibitor (urea) indicated the isozyme present in the quail semen has catalytic properties like LDH-1 viz. H-type. Furthermore, unlike other mammalian species, electrophoretic and kinetic investigations did not support the existence of semen specific LDH-X isozyme in quail semen. The effect of exogenous lactate and pyruvate on sperm metabolic activity was also studied. The addition of 1 mM lactate or pyruvate to quail semen increased sperm metabolic activity. Our results suggested that both pyruvate and lactate could be used by quail spermatozoa to maintain their basic functions. Since the H-type isozyme is important for conversion of lactate to pyruvate under anaerobic conditions it was postulated that exogenous lactate being converted into pyruvate via LDH present in semen may be used by sperm mitochondria to generate ATP. During conversion of lactate to pyruvate NADH is being generated that may be useful for maintaining sperm mitochondrial membrane potential. PMID:21074838

  7. NAD-Independent l-Lactate Dehydrogenase Required for l-Lactate Utilization in Pseudomonas stutzeri A1501

    PubMed Central

    Gao, Chao; Wang, Yujiao; Zhang, Yingxin; Lv, Min; Dou, Peipei; Xu, Ping

    2015-01-01

    ABSTRACT NAD-independent l-lactate dehydrogenases (l-iLDHs) play important roles in l-lactate utilization of different organisms. All of the previously reported l-iLDHs were flavoproteins that catalyze the oxidation of l-lactate by the flavin mononucleotide (FMN)-dependent mechanism. Based on comparative genomic analysis, a gene cluster with three genes (lldA, lldB, and lldC) encoding a novel type of l-iLDH was identified in Pseudomonas stutzeri A1501. When the gene cluster was expressed in Escherichia coli, distinctive l-iLDH activity was detected. The expressed l-iLDH was purified by ammonium sulfate precipitation, ion-exchange chromatography, and affinity chromatography. SDS-PAGE and successive matrix-assisted laser desorption ionization–time of flight mass spectrometry (MALDI-TOF MS) analysis of the purified l-iLDH indicated that it is a complex of LldA, LldB, and LldC (encoded by lldA, lldB, and lldC, respectively). Purified l-iLDH (LldABC) is a dimer of three subunits (LldA, LldB, and LldC), and the ratio between LldA, LldB, and LldC is 1:1:1. Different from the FMN-containing l-iLDH, absorption spectra and elemental analysis suggested that LldABC might use the iron-sulfur cluster for the l-lactate oxidation. LldABC has narrow substrate specificity, and only l-lactate and dl-2-hydrobutyrate were rapidly oxidized. Mg2+ could activate l-iLDH activity effectively (6.6-fold). Steady-state kinetics indicated a ping-pong mechanism of LldABC for the l-lactate oxidation. Based on the gene knockout results, LldABC was confirmed to be required for the l-lactate metabolism of P. stutzeri A1501. LldABC is the first purified and characterized l-iLDH with different subunits that uses the iron-sulfur cluster as the cofactor. IMPORTANCE Providing new insights into the diversity of microbial lactate utilization could assist in the production of valuable chemicals and understanding microbial pathogenesis. An NAD-independent l-lactate dehydrogenase (l-iLDH) encoded by the gene cluster lldABC is indispensable for the l-lactate metabolism in Pseudomonas stutzeri A1501. This novel type of enzyme was purified and characterized in this study. Different from the well-characterized FMN-containing l-iLDH in other microbes, LldABC in P. stutzeri A1501 is a dimer of three subunits (LldA, LldB, and LldC) and uses the iron-sulfur cluster as a cofactor. PMID:25917905

  8. Differential messenger RNA distribution of lactate dehydrogenase LDH-1 and LDH-5 isoforms in the rat brain.

    PubMed

    Laughton, J D; Charnay, Y; Belloir, B; Pellerin, L; Magistretti, P J; Bouras, C

    2000-01-01

    The role of lactate in brain energy metabolism has recently received renewed attention. Although blood-borne monocarboxylates such as lactate poorly cross the blood-brain barrier in the adult brain, lactate produced within the brain parenchyma may be a suitable substrate for brain cells. Lactate dehydrogenase is crucial for both the production and utilization of lactate. In this article, we report the regional distribution of the messenger RNAs for lactate dehydrogenase isoforms 1 and 5 in the adult rat brain using in situ hybridization histochemistry with specific [alpha-(35)S]dATP 3' end-labeled oligoprobes. The autoradiographs revealed that the lactate dehydrogenase-1 messenger RNA is highly expressed in a variety of brain structures, including the main olfactory bulb, the piriform cortex, several thalamic and hypothalamic nuclei, the pontine nuclei, the ventral cochlear nucleus, the trigeminal nerve and the solitary tractus nucleus. In addition, the granular and Purkinje cell layers of the cerebellum showed a strong labeling. The neocortex (e.g., cingular, retrosplenial and frontoparietal cortices) often exhibits a marked laminar pattern of distribution of lactate dehydrogenase-1 messenger RNA (layers II/III, IV and VI being most strongly labeled). In contrast, expression of the lactate dehydrogenase-5 messenger RNA generally seemed more diffusely distributed across the different brain regions. Expression was particularly strong in the hippocampal formation (especially in Ammon's horn and dentate gyrus) and in the cerebral cortex, where no laminar pattern of distribution was observed. Overall, these data are consistent with the emerging idea that lactate is an important energy substrate produced and consumed by brain cells. PMID:10717443

  9. Lactate dehydrogenase and oxidative stress activity in primary open-angle glaucoma aqueous humour.

    PubMed

    Jovanovic, Predrag; Zoric, Lepsa; Stefanovic, Ivan; Dzunic, Boban; Djordjevic-Jocic, Jasmina; Radenkovic, Marija; Jovanovic, Maja

    2010-02-01

    Lactate dehydrogenase (LDH) and lactate are some of the hypoxy biochemical parameters. Extracellular activity of this enzyme increases under the condition of oxidative stress, since the cell integrity can be disrupted during the lipid peroxidation process. Subsequently that leads to the increase level of the lactic acid and lactic acid salts. The objective of this investigation is establishing the level of LDH, LDH1 (HBDH) and the lactate concentration in aqueous humour in patients with primary open-angle glaucoma. Biochemical analysis have been made by enzymatic-colometric method (lactate) and UV-kinetic method (LDH and HBDH) in aqueous humour of 30 patients (42 eyes) with primary open-angle glaucoma (POAG) and 30 patients (40 eyes) with cataract (the control group). The increased values of lactate and the activity of LDH and HBDH enzyme in aqueous humour of POAG patients in correlation with the control group are the results not only of oxidative stress but also of hypoxy and the mitochondry oxidative function (p<0,001). The increased activity of the examined biochemical parameters in the aqueous humour of the POAG patients points to the fact that other mechanisms, besides IOP, have a role in glaucoma pathogenesis. PMID:20192938

  10. Cloning, E. coli expression, and characterization of heart lactate dehydrogenase B from river buffalo (Bubalus bubalis).

    PubMed

    Nadeem, Muhammad Shahid; Moran, Jenny; Murtaza, Bibi Nazia; Muhammad, Khushi; Ahmad, Habib

    2014-01-01

    Lactate dehydrogenase is an enzyme of glycolytic pathway which catalyzes the interconversion of pyruvate and lactate. The present study describes cDNA cloning, E. coli expression and characterization of lactate dehydrogenase B (LDH-B) from the heart ventricles of river buffalo (Bubalus bubalis). Total RNA was isolated from the heart tissue, a 1005bp cDNA encoding complete polypeptide chain of 334 amino acids was generated by reverse transcriptase reaction and analyzed for nucleotide sequence. The consensus sequence obtained from both strands has shown 84% to 98% homology with that of different mammalian species. The attributed gene was cloned, expressed in BL21 (DE3) RIPL Codon Plus strain of E. coli using pET21a (+) plasmid. The purified recombinant enzyme displayed a KM value of 50 µM for pyruvate, an optimum activity at 35°C and pH 7.0. The enzyme was found as a homotetramer of 140 kDa on FPLC based gel-filtration column. Molecular weight of a subunit of enzyme as determined by mass spectrometric analysis was 36530.21 Da. The present study describes the first ever report about the cDNA sequence and characteristics of recombinant LDH-B from River buffalo. PMID:24299182

  11. Factors Affecting the Activity of the Lactate Dehydrogenase of Streptococcus cremoris

    PubMed Central

    Jonas, H. A.; Anders, R. F.; Jago, G. R.

    1972-01-01

    Studies with partially purified extracts of the nicotinamide adenine dinucleotide-linked l(+)-lactate dehydrogenase of Streptococcus cremoris US3 showed that fructose-1,6-diphosphate (FDP) was essential for the catalytic reduction of pyruvate in the pH range 5.0 to 7.0, outside of which the organism does not grow. In the absence of FDP, enzyme activity was observed only in the region of pH 8.0. The optimal pH for the oxidation of lactate was approximately 8.0 in the presence and absence of FDP. The FDP-activated enzyme was markedly inhibited by inorganic phosphate. The enzyme lost activity on standing at 5 C in alkaline triethanolamine, was quite stable at pH 6.0 to 6.5, and underwent irreversible denaturation below pH 5.0. Inorganic phosphate or FDP increased the stability of the enzyme in alkaline buffers. Some distinguishing properties of individual lactate dehydrogenases, activated by FDP, are discussed. PMID:4340864

  12. Lactate Dehydrogenase Is the Key Enzyme for Pneumococcal Pyruvate Metabolism and Pneumococcal Survival in Blood

    PubMed Central

    Gaspar, Paula; Al-Bayati, Firas A. Y.; Andrew, Peter W.; Neves, Ana Rute

    2014-01-01

    Streptococcus pneumoniae is a fermentative microorganism and causes serious diseases in humans, including otitis media, bacteremia, meningitis, and pneumonia. However, the mechanisms enabling pneumococcal survival in the host and causing disease in different tissues are incompletely understood. The available evidence indicates a strong link between the central metabolism and pneumococcal virulence. To further our knowledge on pneumococcal virulence, we investigated the role of lactate dehydrogenase (LDH), which converts pyruvate to lactate and is an essential enzyme for redox balance, in the pneumococcal central metabolism and virulence using an isogenic ldh mutant. Loss of LDH led to a dramatic reduction of the growth rate, pinpointing the key role of this enzyme in fermentative metabolism. The pattern of end products was altered, and lactate production was totally blocked. The fermentation profile was confirmed by in vivo nuclear magnetic resonance (NMR) measurements of glucose metabolism in nongrowing cell suspensions of the ldh mutant. In this strain, a bottleneck in the fermentative steps is evident from the accumulation of pyruvate, revealing LDH as the most efficient enzyme in pyruvate conversion. An increase in ethanol production was also observed, indicating that in the absence of LDH the redox balance is maintained through alcohol dehydrogenase activity. We also found that the absence of LDH renders the pneumococci avirulent after intravenous infection and leads to a significant reduction in virulence in a model of pneumonia that develops after intranasal infection, likely due to a decrease in energy generation and virulence gene expression. PMID:25245810

  13. The influence of oxygen on radiation-induced structural and functional changes in glyceraldehyde-3-phosphate dehydrogenase and lactate dehydrogenase

    NASA Astrophysics Data System (ADS)

    Rodacka, Aleksandra; Serafin, Eligiusz; Bubinski, Michal; Krokosz, Anita; Puchala, Mieczyslaw

    2012-07-01

    Proteins are major targets for oxidative damage due to their abundance in cells and high reactivity with free radicals. In the present study we examined the influence of oxygen on radiation-induced inactivation and structural changes of glyceraldehyde-3-phosphate dehydrogenase (GAPDH) and lactate dehydrogenase (LDH). We chose these two enzymes because they occur at high concentrations and participate in the most important processes in organisms; furthermore, they show considerable similarity in their structure. Protein solutions were irradiated with X-rays in doses ranging from 0.1 to 0.7 kGy, in air and N2O. The much higher radiation inactivation of GAPDH as compared to LDH is correlated with substantially greater structural changes in this protein, mainly involving the loss of free thiol groups (-SH). Of lesser importance in the differentiation of the radiosensitivity of the studied enzymes are tryptophan residues. Molecular oxygen, present during irradiation, increased to a significantly greater extent the inactivation and structural changes of GAPDH than that of LDH. The results suggest that the greater effect of oxygen on GAPDH is due to the higher efficiency of the superoxide radical, the higher amount of hydroperoxides generated, and the higher degree of unfolding of this protein.

  14. Suppression of lactate dehydrogenase A compromises tumor progression by downregulation of the Warburg effect in glioblastoma

    PubMed Central

    Li, Juan; Tong, Jing; Hao, Hui; Yang, Jie; Liu, Zhikun; Wang, Yuxiang

    2016-01-01

    Reprogrammed glucose metabolism is an emerging hallmark of cancer cells, which show a unique metabolic phenotype known as the Warburg effect. Lactate dehydrogenase A (LDHA), a key enzyme in the glycolytic process, executes the final step by conversion of lactate into pyruvate. However, little is known about the roles of LDHA in human glioblastoma (GBM). In this study, we aimed to determine the effects of LDHA and elucidate related underlying mechanisms. Data derived from Oncomine database showed that LDHA is commonly upregulated in GBM tissues in comparison with corresponding normal controls. Silencing of LDHA expression resulted in reduced glycolysis, decreased cell growth, increased cell apoptosis, and attenuated invasive ability. In the presence of 2-deoxyglucose, a glycolysis inhibitor, the oncogenic activities of LDHA were completely blocked. These findings provide evidence of the cellular functions of LDHA in the progression of GBM and suggest that LDHA might act as a potential therapeutic target for GBM treatment. PMID:26694942

  15. Identification of 3,6-disubstituted dihydropyrones as inhibitors of human lactate dehydrogenase.

    PubMed

    Fauber, Benjamin P; Dragovich, Peter S; Chen, Jinhua; Corson, Laura B; Ding, Charles Z; Eigenbrot, Charles; Labadie, Sharada; Malek, Shiva; Peterson, David; Purkey, Hans E; Robarge, Kirk; Sideris, Steve; Ultsch, Mark; Wei, BinQing; Yen, Ivana; Yue, Qin; Zhou, Aihe

    2014-12-15

    A series of 3,6-disubstituted dihydropyrones were identified as inhibitors of human lactate dehydrogenase (LDH)-A. Structure activity relationships were explored and a series of 6,6-spiro analogs led to improvements in LDHA potency (IC50 <350 nM). An X-ray crystal structure of an improved compound bound to human LDHA was obtained and it illustrated additional opportunities to enhance the potency of these compounds, resulting in the identification of 51 (IC50=30 nM). PMID:25467161

  16. Evaluation of the anti-tumor effects of lactate dehydrogenase inhibitor galloflavin in endometrial cancer cells.

    PubMed

    Han, Xiaoyun; Sheng, Xiugui; Jones, Hannah M; Jackson, Amanda L; Kilgore, Joshua; Stine, Jessica E; Schointuch, Monica N; Zhou, Chunxiao; Bae-Jump, Victoria L

    2015-01-01

    High rates of aerobic glycolysis represent a key mechanism by which endometrial cancer cells consume glucose as its primary energy source. The up-regulated glycolytic pathway is a common therapeutic target whose inhibition has implications for anti-tumor activity in cancer cells. The present study was aimed at evaluating the potential of a novel lactate dehydrogenase (LDH) inhibitor, Galloflavin, as a therapeutic agent for endometrial cancer. Our results revealed that Galloflavin effectively inhibited cell growth in endometrial cancer cell lines and primary cultures of human endometrial cancer through its involvement in multiple signaling pathways that regulate metabolism, cell cycle, apoptosis, cell stress and metastasis. PMID:25631326

  17. Resting oxygen consumption varies among lactate dehydrogenase genotypes in the sow bug, Porcellio scaber

    PubMed Central

    Mitton, J. B.; Carter, P. A.; DiGiacomo, A.

    1997-01-01

    Laboratory studies of respiration in the sow bug, Porcellio scaber, reveal that respiration rates are related to genetic variation at the lactate dehydrogenase (Ldh) locus. In population samples taken from Burlington, North Carolina and Pacific Grove, California, respiration rates differed among Ldh genotypes, but not among genotypes at the other enzyme polymorphisms. In both population samples, the respiration rate of the common Ldh homozygote exceeded the respiration rate of the heterozygote by more than 50 per cent. The differences in respiration rates are consistent with previously reported viability differentials at the Ldh polymorphism.

  18. Substrate-induced conformational changes in lactate dehydrogenase. Proteolysis of the immobilized enzyme in the presence of specific substrates.

    PubMed

    Royer, G P; Ikeda, S I; Lee, T K

    1977-12-25

    We report here a new approach to the study of the conformation of enzymes in the presence of specific substrates. Rabbit muscle lactate dehydrogenase was attached to CL-Sepharose via a cleavable spacer arm (-NH-(CH2)6NHCO(CH2)2SS(CH2)2CO-). The bound lactate dehydrogenase was digested with subtilisin BPN' in the presence of substrates of lactate dehydrogenase. The use of a flow system permits the maintenance of saturating levels of substrates. Proteolysis was followed by loss of activity of the enzyme column. The time course of proteolysis in the presence of either NADH, NAD+, or pyruvate alone did not differ from the control. However, when NADH and pyruvate were present simultaneously, the enzyme became more susceptible to proteolysis. The initial rate of proteolysis was increased by 40%. The abortive ternary complex (lactate dehydrogenase - NAD+ - pyruvate) also showed an increase in susceptibility to proteolysis. These findings clearly show that the productive ternary complex (lactate dehydrogenase - NADH - pyruvate) is conformationally different from the apoenzyme and binary complexes under optimal catalytic conditions. PMID:200617

  19. Cloning of a lactate dehydrogenase gene from Clostridium acetobutylicum B643 and expression in Escherichia coli

    SciTech Connect

    Contag, P.R.; Williams, M.G.; Rogers, P. )

    1990-12-01

    A lactate dehydrogenase (LDH) gene of Clostridium acetobutylicum B643 was cloned on two recombinant plasmids. pPC37 and pPC58, that were selected by complementation of Escherichia coli PRC436 (acd), a fermentation-defective mutant that does not grown anaerobically on glucose. E. coli PRC436(pPC37) and PRC436(pPC58) grew anaerobically and fermented glucose to mostly lactate. When pPC37 and pPC58 were transformed into E. coli FMJ39 (ldh pfl), an LDH-deficient strain, the resulting strains grew anaerobically on glucose and produced lactate. Crude extracts of E. coli FMJ39(pPC37) and FMJ39(pPC58) contained high LDH activity only when assayed for pyruvate reduction to lactate, and the LDH activity was activated 15- to 30-fold by the addition of fructose 1,6-diphosphate (FDP). E. coli FMJ39 had no detectable LDH activity, and E. coli LDH from a wild-type strain was not activated by FDP. Maxicell analysis showed that both plasmids pPC37 and pPC58 expressed a protein with an apparent M{sub r} of 38,000 in sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Restriction endonuclease mapping of pPC37 and pPC58 and DNA hybridization studies indicated that a 2.1-kb region of these two clones of C. acetobutylicum DNA encodes the FDP-activated LDH.

  20. Molecular and Kinetic Characterization of Babesia microti Gray Strain Lactate Dehydrogenase as a Potential Drug Target

    PubMed Central

    Vudriko, Patrick; Masatani, Tatsunori; Cao, Shinuo; Terkawi, Mohamad Alla; Kamyingkird, Ketsarin; Mousa, Ahmed A; Adjou Moumouni, Paul F; Nishikawa, Yoshifumi; Xuan, Xuenan

    2014-01-01

    Babesia microti is an emerging zoonotic protozoan organism that causes “malaria-like” symptoms that can be fatal in immunocompromised people. Owing to lack of specific therapeutic regiment against the disease, we cloned and characterized B. microti lactate dehydrogenase (BmLDH) as a potential molecular drug receptor. The in vitro kinetic properties of BmLDH enzyme was evaluated using nicotinamide adenine dinucleotide (NAD+) as a co-factor and lactate as a substrate. Inhibitory assay was also done using gossypol as BmLDH inhibitor to determine the inhibitory concentration 50 (IC50). The result showed that the 0.99 kbp BmLDH gene codes for a barely soluble 36 kDa protein (332 amino acids) localized in both the cytoplasm and nucleus of the parasite. In vitro enzyme kinetic studies further revealed that BmLDH is an active enzyme with a high catalytic efficiency at optimal pH of 10.2. The Km values of NAD+ and lactate were 8.7 ± 0.57 mM and 99.9 ± 22.33 mM, respectively. The IC50 value for gossypol was 0.345 μM, while at 2.5 μM, gossypol caused 100% inhibition of BmLDH catalytic activity. These findings, therefore, provide initial evidence that BmLDH could be a potential drug target, although further in vivo studies are needed to validate the practical application of lactate dehydrogenase inhibitors against B. microti infection. PMID:25125971

  1. Crystal structure and thermodynamic properties of d-lactate dehydrogenase from Lactobacillus jensenii.

    PubMed

    Kim, Sangwoo; Gu, Sol-A; Kim, Yong Hwan; Kim, Kyung-Jin

    2014-07-01

    The thermostable d-lactate dehydrogenase from Lactobacillus jensenii (Ljd-LDH) is a key enzyme in the production of the d-form of lactic acid from pyruvate concomitant with the oxidation of NADH to NAD(+). The polymers of d-lactic acid are used as biodegradable bioplastics. The crystal structures of Ljd-LDH and in complex with NAD(+) were determined at 2.13 and 2.60Å resolutions, respectively. The Ljd-LDH monomer consists of the N-terminal substrate-binding domain and the C-terminal NAD-binding domain. The Ljd-LDH forms a homodimeric structure, and the C-terminal NAD-binding domain mostly enables the dimerization of the enzyme. The NAD cofactor is bound to the GxGxxG NAD-binding motif located between the two domains. Structural comparisons of Ljd-LDH with other d-LDHs reveal that Ljd-LDH has unique amino acid residues at the linker region, which indicates that the open-close dynamics of Ljd-LDH might be different from that of other d-LDHs. Moreover, thermostability experiments showed that the T50(10) value of Ljd-LDH (54.5°C) was much higher than the commercially available d-lactate dehydrogenase (42.7°C). In addition, Ljd-LDH has at least a 7°C higher denaturation temperature compared to commercially available d-LDHs. PMID:24794195

  2. Novel biohybrids of layered double hydroxide and lactate dehydrogenase enzyme: Synthesis, characterization and catalytic activity studies

    NASA Astrophysics Data System (ADS)

    Djebbi, Mohamed Amine; Braiek, Mohamed; Hidouri, Slah; Namour, Philippe; Jaffrezic-Renault, Nicole; Ben Haj Amara, Abdesslem

    2016-02-01

    The present work introduces new biohybrid materials involving layered double hydroxides (LDH) and biomolecule such as enzyme to produce bioinorganic system. Lactate dehydrogenase (Lac Deh) has been chosen as a model enzyme, being immobilized onto MgAl and ZnAl LDH materials via direct ion-exchange (adsorption) and co-precipitation methods. The immobilization efficiency was largely dependent upon the immobilization methods. A comparative study shows that the co-precipitation method favors the immobilization of great and tunable amount of enzyme. The structural behavior, chemical bonding composition and morphology of the resulting biohybrids were determined by X-ray diffraction (XRD) study, Fourier transform infrared (FTIR) spectroscopy and transmission electron microscopy (TEM), respectively. The free and immobilized enzyme activity and kinetic parameters were also reported using UV-Visible spectroscopy. However, the modified LDH materials showed a decrease in crystallinity as compared to the unmodified LDH. The change in activity of the immobilized lactate dehydrogenase was considered to be due, to the reduced accessibility of substrate molecules to the active sites of the enzyme and the partial conformational change of the Lac Deh molecules as a result of the immobilization way. Finally, it was proven that there is a correlation between structure/microstructure and enzyme activity dependent on the immobilization process.

  3. Metabolic compartmentalization in the human cortex and hippocampus: evidence for a cell- and region-specific localization of lactate dehydrogenase 5 and pyruvate dehydrogenase

    PubMed Central

    Laughton, Jocelyn D; Bittar, Philippe; Charnay, Yves; Pellerin, Luc; Kovari, Enikö; Magistretti, Pierre J; Bouras, Constantin

    2007-01-01

    Background For a long time now, glucose has been thought to be the main, if not the sole substrate for brain energy metabolism. Recent data nevertheless suggest that other molecules, such as monocarboxylates (lactate and pyruvate mainly) could be suitable substrates. Although monocarboxylates poorly cross the blood brain barrier (BBB), such substrates could replace glucose if produced locally. The two key enzymatiques systems required for the production of these monocarboxylates are lactate dehydrogenase (LDH; EC1.1.1.27) that catalyses the interconversion of lactate and pyruvate and the pyruvate dehydrogenase complex that irreversibly funnels pyruvate towards the mitochondrial TCA and oxydative phosphorylation. Results In this article, we show, with monoclonal antibodies applied to post-mortem human brain tissues, that the typically glycolytic isoenzyme of lactate dehydrogenase (LDH-5; also called LDHA or LDHM) is selectively present in astrocytes, and not in neurons, whereas pyruvate dehydrogenase (PDH) is mainly detected in neurons and barely in astrocytes. At the regional level, the distribution of the LDH-5 immunoreactive astrocytes is laminar and corresponds to regions of maximal 2-deoxyglucose uptake in the occipital cortex and hippocampus. In hippocampus, we observed that the distribution of the oxidative enzyme PDH was enriched in the neurons of the stratum pyramidale and stratum granulosum of CA1 through CA4, whereas the glycolytic enzyme LDH-5 was enriched in astrocytes of the stratum moleculare, the alveus and the white matter, revealing not only cellular, but also regional, selective distributions. The fact that LDH-5 immunoreactivity was high in astrocytes and occurred in regions where the highest uptake of 2-deoxyglucose was observed suggests that glucose uptake followed by lactate production may principally occur in these regions. Conclusion These observations reveal a metabolic segregation, not only at the cellular but also at the regional level, that support the notion of metabolic compartmentalization between astrocytes and neurons, whereby lactate produced by astrocytes could be oxidized by neurons. PMID:17521432

  4. Structures of lactate dehydrogenase A (LDHA) in apo, ternary and inhibitor-bound forms.

    PubMed

    Kolappan, Subramaniapillai; Shen, David L; Mosi, Renee; Sun, Jianyu; McEachern, Ernest J; Vocadlo, David J; Craig, Lisa

    2015-02-01

    Lactate dehydrogenase (LDH) is an essential metabolic enzyme that catalyzes the interconversion of pyruvate and lactate using NADH/NAD(+) as a co-substrate. Many cancer cells exhibit a glycolytic phenotype known as the Warburg effect, in which elevated LDH levels enhance the conversion of glucose to lactate, making LDH an attractive therapeutic target for oncology. Two known inhibitors of the human muscle LDH isoform, LDHA, designated 1 and 2, were selected, and their IC50 values were determined to be 14.4 3.77 and 2.20 0.15?M, respectively. The X-ray crystal structures of LDHA in complex with each inhibitor were determined; both inhibitors bind to a site overlapping with the NADH-binding site. Further, an apo LDHA crystal structure solved in a new space group is reported, as well as a complex with both NADH and the substrate analogue oxalate bound in seven of the eight molecules and an oxalate only bound in the eighth molecule in the asymmetric unit. In this latter structure, a kanamycin molecule is located in the inhibitor-binding site, thereby blocking NADH binding. These structures provide insights into LDHA enzyme mechanism and inhibition and a framework for structure-assisted drug design that may contribute to new cancer therapies. PMID:25664730

  5. Novel control of lactate dehydrogenase from the freeze tolerant wood frog: role of posttranslational modifications.

    PubMed

    Abboud, Jean; Storey, Kenneth B

    2013-01-01

    Lactate dehydrogenase (LDH), the terminal enzyme of anaerobic glycolysis, plays a crucial role both in sustaining glycolytic ATP production under oxygen-limiting conditions and in facilitating the catabolism of accumulated lactate when stress conditions are relieved. In this study, the effects on LDH of in vivo freezing and dehydration stresses (both of which impose hypoxia/anoxia stress on tissues) were examined in skeletal muscle of the freeze-tolerant wood frog, Rana sylvatica. LDH from muscle of control, frozen and dehydrated wood frogs was purified to homogeneity in a two-step process. The kinetic properties and stability of purified LDH were analyzed, revealing no significant differences in V max, K m and I 50 values between control and frozen LDH. However, control and dehydrated LDH differed significantly in K m values for pyruvate, lactate, and NAD, I 50 urea, and in temperature, glucose, and urea effects on these parameters. The possibility that posttranslational modification of LDH was responsible for the stable differences in enzyme behavior between control and dehydrated states was assessed using ProQ diamond staining to detect phosphorylation and immunoblotting to detect acetylation, methylation, ubiquitination, SUMOylation and nitrosylation of the enzyme. LDH from muscle of dehydrated wood frogs showed significantly lower levels of acetylation, providing one of the first demonstrations of a potential role for protein acetylation in the stress-responsive control of a metabolic enzyme. PMID:23638346

  6. Novel control of lactate dehydrogenase from the freeze tolerant wood frog: role of posttranslational modifications

    PubMed Central

    Abboud, Jean

    2013-01-01

    Lactate dehydrogenase (LDH), the terminal enzyme of anaerobic glycolysis, plays a crucial role both in sustaining glycolytic ATP production under oxygen-limiting conditions and in facilitating the catabolism of accumulated lactate when stress conditions are relieved. In this study, the effects on LDH of in vivo freezing and dehydration stresses (both of which impose hypoxia/anoxia stress on tissues) were examined in skeletal muscle of the freeze-tolerant wood frog, Rana sylvatica. LDH from muscle of control, frozen and dehydrated wood frogs was purified to homogeneity in a two-step process. The kinetic properties and stability of purified LDH were analyzed, revealing no significant differences in Vmax, Km and I50 values between control and frozen LDH. However, control and dehydrated LDH differed significantly in Km values for pyruvate, lactate, and NAD, I50 urea, and in temperature, glucose, and urea effects on these parameters. The possibility that posttranslational modification of LDH was responsible for the stable differences in enzyme behavior between control and dehydrated states was assessed using ProQ diamond staining to detect phosphorylation and immunoblotting to detect acetylation, methylation, ubiquitination, SUMOylation and nitrosylation of the enzyme. LDH from muscle of dehydrated wood frogs showed significantly lower levels of acetylation, providing one of the first demonstrations of a potential role for protein acetylation in the stress-responsive control of a metabolic enzyme. PMID:23638346

  7. Metabolic Control of Anaerobic Glycolysis (Overexpression of Lactate Dehydrogenase in Transgenic Tomato Roots Supports the Davies-Roberts Hypothesis and Points to a Critical Role for Lactate Secretion.

    PubMed Central

    Rivoal, J.; Hanson, A. D.

    1994-01-01

    Roots of all plants examined so far have the potential for both ethanol and lactate fermentation. A short burst of lactate fermentation usually occurs when plant tissues are transferred from normoxic to anoxic conditions. According to the Davies-Roberts hypothesis, the consequent pH drop both initiates ethanol fermentation and blocks further production of lactate by inhibiting lactate dehydrogenase (LDH). However, the role of LDH in this pH control mechanism is still a matter of debate. To perturb the control system in a defined way, a barley LDH cDNA under the control of the cauliflower mosaic virus 35S promoter was introduced into tomato (Lycopersicon esculentum Mill. cv VFMT) using Agrobacterium rhizogenes. The transgenic root clones expressed up to 50 times the LDH activity of controls. The fermentative metabolism of these clones was compared using roots grown previously in normoxic conditions or roots given a 3-d hypoxic pretreatment. During the transition from normoxia to anoxia, lactate accumulation was no faster and no more extensive in transgenic roots than in controls. Similarly, during prolonged anoxia the flux of 14C from [U-14C] glucose to lactate and ethanol was not modified by the expression of the transgene. However, in both transgenic and control roots, hypoxic pretreatment increased the flux to lactate and promoted lactate export to the medium. These results show that LDH has a very low flux control coefficient for lactate fermentation, consistent with the Davies-Roberts hypothesis. Moreover, they suggest that lactate secretion exerts major control over long-term lactate glycolysis in vivo. PMID:12232401

  8. Complete Nucleotide Sequence of the Mouse Lactate Dehydrogenase-a Functional Gene: Comparison of the Exon-Intron Organization of Dehydrogenase Genes

    PubMed Central

    Fukasawa, Kayoko M.; Li, Steven S.-L.

    1987-01-01

    The complete sequence of 12,851 nucleotides of the mouse lactate dehydrogenase-A (LDH-A) gene has been determined. It includes eight exons, seven introns, promoter and regulatory regions. The B1 repetitive elements present in intron III and VI are oriented in opposite orientation, and they share 72% sequence homology. The exon-intron organization of mouse LDH-A gene is compared with the organizations of other dehydrogenase genes, and the molecular evolution of the nicotinamide adenine dinucleotide binding domains is discussed. PMID:3036647

  9. Identification of substituted 3-hydroxy-2-mercaptocyclohex-2-enones as potent inhibitors of human lactate dehydrogenase.

    PubMed

    Dragovich, Peter S; Fauber, Benjamin P; Boggs, Jason; Chen, Jinhua; Corson, Laura B; Ding, Charles Z; Eigenbrot, Charles; Ge, HongXiu; Giannetti, Anthony M; Hunsaker, Thomas; Labadie, Sharada; Li, Chiho; Liu, Yichin; Liu, Yingchun; Ma, Shuguang; Malek, Shiva; Peterson, David; Pitts, Keith E; Purkey, Hans E; Robarge, Kirk; Salphati, Laurent; Sideris, Steve; Ultsch, Mark; VanderPorten, Erica; Wang, Jing; Wei, BinQing; Xu, Qing; Yen, Ivana; Yue, Qin; Zhang, Huihui; Zhang, Xuying; Zhou, Aihe

    2014-08-15

    A novel class of 3-hydroxy-2-mercaptocyclohex-2-enone-containing inhibitors of human lactate dehydrogenase (LDH) was identified through a high-throughput screening approach. Biochemical and surface plasmon resonance experiments performed with a screening hit (LDHA IC50=1.7 μM) indicated that the compound specifically associated with human LDHA in a manner that required simultaneous binding of the NADH co-factor. Structural variation of this screening hit resulted in significant improvements in LDHA biochemical inhibition activity (best IC50=0.18 μM). Two crystal structures of optimized compounds bound to human LDHA were obtained and explained many of the observed structure-activity relationships. In addition, an optimized inhibitor exhibited good pharmacokinetic properties after oral administration to rats (F=45%). PMID:25037916

  10. A rapid beta-NADH-linked fluorescence assay for lactate dehydrogenase in cellular death.

    PubMed

    Moran, J H; Schnellmann, R G

    1996-09-01

    Lactate dehydrogenase (LDH) release in a common marker of cellular death. Traditionally, the fraction of LDH released has been measured using a NADH-linked UV-Vis spectrophotometric method. The limitation of this method is that samples are usually run serially and thus is time intensive. Therefore, we developed a NADH-linked LDH assay using a fluorescence plate reader that had a correlation of 0.95 with the traditional UV-Vis spectrophotometric method. Using rabbit renal proximal tubule suspensions at a concentration of 1 mg cellular protein/ml of media, the fluorescence assay can determine LDH release in 22 samples in 2 min using 12 microL of cellular homogenates and 150 microL of media. The parallel processing of samples and smaller volumes used in the fluorescence assay results in decreased analysis time and costs. PMID:8872918

  11. [Species specificity of the isoenzyme profile of lactate dehydrogenase in organs of rodents of various ecogenesis].

    PubMed

    Kozhevnikova, L K; Tiutiunnik, N N; Unzhakov, A R; Meldo, Kh I

    2004-02-01

    Separation of isoenzymes of lactate dehydrogenase (LDH, EC. 1.1.1.27) in extracts of heart, kidney, liver, spleen, lungs of nutrias, chinchillas by agar gel electrophoresis reveals a species specificity in ratio of electrophoretic fractions of the enzyme. The isoenzymes of LDH were seem to play an important role in adaptation of fur animals to environmental conditions. It has been shown that in semiaquatic mammals--nutrias, the relative content of the A-subunits in the isoenzymatic spectrum of LDH in organs was increased as compared with terrestrial animals--chinchillas, whereas relative content of B-subunits in these organs of chinchillas was very high. This is an example of subtle biochemical specialisation of function at molecular level to environmental conditions. PMID:15143506

  12. Phenylpropanoids and flavonoids from Phlomis kurdica as inhibitors of human lactate dehydrogenase.

    PubMed

    Bader, Ammar; Tuccinardi, Tiziano; Granchi, Carlotta; Martinelli, Adriano; Macchia, Marco; Minutolo, Filippo; De Tommasi, Nunziatina; Braca, Alessandra

    2015-08-01

    Two flavonoids, jaceosidin 7-O-β-d-glucopyranosyl-(1→2)-β-d-glucopyranoside (1) and hispidulin 7-O-β-d-glucopyranosyl-(1→2)-β-d-glucopyranoside (2), and one phenylpropanoid, 3,3'-dimethyl-lunariifolioside (3), along with 11 known compounds (4-14), were isolated from the aerial parts of Phlomis kurdica growing in Jordan. Structures of 1-3 were elucidated on the basis of spectroscopic data. These isolated compounds were assayed for their inhibitory activity against isoform 5 of human lactate dehydrogenase. Compound 4, luteolin 7-O-β-d-glucopyranoside, showed an IC50 value comparable to that of galloflavin, used as reference compound. Docking studies were carried out to hypothesize the interaction mode of compound 4 in the enzyme active site. PMID:25890391

  13. Lactate dehydrogenase and its isoenzymes in serum from patients with multiple myeloma.

    PubMed

    Copur, S; Kus, S; Kars, A; Renda, N; Tekuzman, G; Firat, D

    1989-09-01

    Concentrations of total lactate dehydrogenase (LDH; EC 1.1.1.27) and LDH isoenzyme patterns were studied in serum of 19 patients with multiple myeloma and in 19 healthy controls. Patients were divided into three groups (pretreatment, nonresponders, and responders to treatment), based on their clinical status at the time of blood sampling for LDH. The LDH values were found to be significantly higher (P less than 0.05) in the pretreatment group and in the nonresponders than in the responders and the control group, the mean +/- SE values being 445 +/- 35 and 532 +/- 75 units/mL vs 349 +/- 75 and 190 +/- 7.1 units/mL, respectively. Compared with responders and healthy controls, newly diagnosed patients and nonresponders had slight diminutions in LDH-1 and LDH-2, but increased LDH-3. We conclude that determination of LDH and its isoenzymes in serum can be of value as prognostic factors in patients with multiple myeloma. PMID:2776328

  14. Analysis of lactate dehydrogenase activities and isoenzyme patterns in colorectal cancer tissues

    PubMed Central

    Zhao, Chun-Hua; Jiang, Chun-Ying; Zhang, Yu-Yi; Liu, Xian-Xi; Luo, Dao-Chun; Zhang, Xiao-Ting; Lin, Yu-Qin

    1997-01-01

    AIM: To investigate the relationship between lactate dehydrogenase (LDH) activity or LDH isoenzyme patterns and the pathogenesis of colorectal cancer. METHODS: Activities of tissue LDH and LDH isoenzyme patterns in 16 patients with colorectal cancer were assayed using spectrophotometric procedures and agarose gel electrophoresis, respectively. RESULTS: The total and specific activities of LDH were significantly higher in colorectal cancer tissues than those in adjacent noncancerous tissues (P < 0.001). The LDH isoenzyme pattern was also different from that in the control. The percentage of LDH5 doubled and the ratio of LDH4 + LDH5/LDH1 + LDH2 was 3.6 ± 1.4 in cancer tissue, significantly greater than in the control. CONCLUSIONS: The increased LDH activity in colorectal cancer tissues resulted mainly from the increased LDH5, suggesting that the alteration of LDH activity and isoenzyme patterns were related to the pathogenesis of colorectal cancer.

  15. Development of L-lactate dehydrogenase biosensor based on porous silicon resonant microcavities as fluorescence enhancers.

    PubMed

    Jenie, S N Aisyiyah; Prieto-Simon, Beatriz; Voelcker, Nicolas H

    2015-12-15

    The up-regulation of L-lactate dehydrogenase (LDH), an intracellular enzyme present in most of all body tissues, is indicative of several pathological conditions and cellular death. Herein, we demonstrate LDH detection using porous silicon (pSi) microcavities as a luminescence-enhancing optical biosensing platform. Non-fluorescent resazurin was covalently attached onto the pSi surface via thermal hydrocarbonisation, thermal hydrosylilation and acylation. Each surface modification step was confirmed by means of FTIR and the optical shifts of the resonance wavelength of the microcavity. Thermal hydrocarbonisation also afforded excellent surface stability, ensuring that the resazurin was not reduced on the pSi surface. Using a pSi microcavity biosensor, the fluorescence signal upon detection of LDH was amplified by 10 and 5-fold compared to that of a single layer and a detuned microcavity, respectively, giving a limit of detection of 0.08 U/ml. The biosensor showed a linear response between 0.16 and 6.5 U/ml, covering the concentration range of LDH in normal as well as damaged tissues. The biosensor was selective for LDH and did not produce a signal upon incubation with another NAD-dependant enzyme L-glutamic dehydrogenase. The use of the pSi microcavity as a sensing platform reduced reagent usage by 30% and analysis time threefold compared to the standard LDH assay in solution. PMID:26201980

  16. Free energy landscape of the Michaelis complex of lactate dehydrogenase: A network analysis of atomistic simulations

    NASA Astrophysics Data System (ADS)

    Pan, Xiaoliang; Schwartz, Steven

    2015-03-01

    It has long been recognized that the structure of a protein is a hierarchy of conformations interconverting on multiple time scales. However, the conformational heterogeneity is rarely considered in the context of enzymatic catalysis in which the reactant is usually represented by a single conformation of the enzyme/substrate complex. Lactate dehydrogenase (LDH) catalyzes the interconversion of pyruvate and lactate with concomitant interconversion of two forms of the cofactor nicotinamide adenine dinucleotide (NADH and NAD+). Recent experimental results suggest that multiple substates exist within the Michaelis complex of LDH, and they are catalytic competent at different reaction rates. In this study, millisecond-scale all-atom molecular dynamics simulations were performed on LDH to explore the free energy landscape of the Michaelis complex, and network analysis was used to characterize the distribution of the conformations. Our results provide a detailed view of the kinetic network the Michaelis complex and the structures of the substates at atomistic scale. It also shed some light on understanding the complete picture of the catalytic mechanism of LDH.

  17. Epitopes of human testis-specific lactate dehydrogenase deduced from a cDNA sequence

    SciTech Connect

    Millan, J.L.; Driscoll, C.E.; LeVan, K.M.; Goldberg, E.

    1987-08-01

    The sequence and structure of human testis-specific L-lactate dehydrogenase (LDHC/sub 4/, LDHX; (L)-lactate:NAD/sup +/ oxidoreductase, EC 1.1.1.27) has been derived from analysis of a complementary DNA (cDNA) clone comprising the complete protein coding region of the enzyme. From the deduced amino acid sequence, human LDHC/sub 4/ is as different from rodent LDHC/sub 4/ (73% homology) as it is from human LDHA/sub 4/ (76% homology) and porcine LDHB/sub 4/ (68% homology). Subunit homologies are consistent with the conclusion that the LDHC gene arose by at least two independent duplication events. Furthermore, the lower degree of homology between mouse and human LDHC/sub 4/ and the appearance of this isozyme late in evolution suggests a higher rate of mutation in the mammalian LDHC genes than in the LDHA and -B genes. Comparison of exposed amino acid residues of discrete anti-genic determinants of mouse and human LDHC/sub 4/ reveals significant differences. Knowledge of the human LDHC/sub 4/ sequence will help design human-specific peptides useful in the development of a contraceptive vaccine.

  18. Direct Evidence of Catalytic Heterogeneity in Lactate Dehydrogenase by Temperature Jump Infrared Spectroscopy

    PubMed Central

    2015-01-01

    Protein conformational heterogeneity and dynamics are known to play an important role in enzyme catalysis, but their influence has been difficult to observe directly. We have studied the effects of heterogeneity in the catalytic reaction of pig heart lactate dehydrogenase using isotope edited infrared spectroscopy, laser-induced temperature jump relaxation, and kinetic modeling. The isotope edited infrared spectrum reveals the presence of multiple reactive conformations of pyruvate bound to the enzyme, with three major reactive populations having substrate C2 carbonyl stretches at 1686, 1679, and 1674 cm–1, respectively. The temperature jump relaxation measurements and kinetic modeling indicate that these substates form a heterogeneous branched reaction pathway, and each substate catalyzes the conversion of pyruvate to lactate with a different rate. Furthermore, the rate of hydride transfer is inversely correlated with the frequency of the C2 carbonyl stretch (the rate increases as the frequency decreases), consistent with the relationship between the frequency of this mode and the polarization of the bond, which determines its reactivity toward hydride transfer. The enzyme does not appear to be optimized to use the fastest pathway preferentially but rather accesses multiple pathways in a search process that often selects slower ones. These results provide further support for a dynamic view of enzyme catalysis where the role of the enzyme is not just to bring reactants together but also to guide the conformational search for chemically competent interactions. PMID:25149276

  19. Lactate dehydrogenase-A inhibition induces human glioblastoma multiforme stem cell differentiation and death

    PubMed Central

    Daniele, Simona; Giacomelli, Chiara; Zappelli, Elisa; Granchi, Carlotta; Trincavelli, Maria Letizia; Minutolo, Filippo; Martini, Claudia

    2015-01-01

    Therapies that target the signal transduction and metabolic pathways of cancer stem cells (CSCs) are innovative strategies to effectively reduce the recurrence and significantly improve the outcome of glioblastoma multiforme (GBM). CSCs exhibit an increased rate of glycolysis, thus rendering them intrinsically more sensitive to prospective therapeutic strategies based on the inhibition of the glycolytic pathway. The enzyme lactate dehydrogenase-A (LDH-A), which catalyses the interconversion of pyruvate and lactate, is up-regulated in human cancers, including GBM. Although several papers have explored the benefits of targeting cancer metabolism in GBM, the effects of direct LDH-A inhibition in glial tumours have not yet been investigated, particularly in the stem cell subpopulation. Here, two representative LDH-A inhibitors (NHI-1 and NHI-2) were studied in GBM-derived CSCs and compared to differentiated tumour cells. LDH-A inhibition was particularly effective in CSCs isolated from different GBM cell lines, where the two compounds blocked CSC formation and elicited long-lasting effects by triggering both apoptosis and cellular differentiation. These data demonstrate that GBM, particularly the stem cell subpopulation, is sensitive to glycolytic inhibition and shed light on the therapeutic potential of LDH-A inhibitors in this tumour type. PMID:26494310

  20. Surface modification of silicon dioxide, silicon nitride and titanium oxynitride for lactate dehydrogenase immobilization.

    PubMed

    Saengdee, Pawasuth; Chaisriratanakul, Woraphan; Bunjongpru, Win; Sripumkhai, Witsaroot; Srisuwan, Awirut; Jeamsaksiri, Wutthinan; Hruanun, Charndet; Poyai, Amporn; Promptmas, Chamras

    2015-05-15

    Three different types of surface, silicon dioxide (SiO2), silicon nitride (Si3N4), and titanium oxynitride (TiON) were modified for lactate dehydrogenase (LDH) immobilization using (3-aminopropyl)triethoxysilane (APTES) to obtain an amino layer on each surface. The APTES modified surfaces can directly react with LDH via physical attachment. LDH can be chemically immobilized on those surfaces after incorporation with glutaraldehyde (GA) to obtain aldehyde layers of APTES-GA modified surfaces. The wetting properties, chemical bonding composition, and morphology of the modified surface were determined by contact angle (CA) measurement, Fourier transform infrared (FTIR) spectroscopy, and scanning electron microscopy (SEM), respectively. In this experiment, the immobilized protein content and LDH activity on each modified surface was used as an indicator of surface modification achievement. The results revealed that both the APTES and APTES-GA treatments successfully link the LDH molecule to those surfaces while retaining its activity. All types of tested surfaces modified with APTES-GA gave better LDH immobilizing efficiency than APTES, especially the SiO2 surface. In addition, the SiO2 surface offered the highest LDH immobilization among tested surfaces, with both APTES and APTES-GA modification. However, TiON and Si3N4 surfaces could be used as alternative candidate materials in the preparation of ion-sensitive field-effect transistor (ISFET) based biosensors, including lactate sensors using immobilized LDH on the ISFET surface. PMID:25108848

  1. Positive selection on D-lactate dehydrogenases of Lactobacillus delbrueckii subspecies bulgaricus.

    PubMed

    Zhang, Jifeng; Gong, Guangyu; Wang, Xiao; Zhang, Hao; Tian, Weidong

    2015-08-01

    Lactobacillus delbrueckii has been widely used for yogurt fermentation. It has genes encoding both D- and L-type lactate dehydrogenases (LDHs) that catalyse the production of L(+) or D(-) stereoisomer of lactic acid. D-lactic acid is the primary lactate product by L. delbrueckii, yet it cannot be metabolised by human intestine. Since it has been domesticated for long time, an interesting question arises regarding to whether the selection pressure has affected the evolution of both L-LDH and D-LDH genes in the genome. To answer this question, in this study the authors first investigated the evolution of these two genes by constructing phylogenetic trees. They found that D-LDH-based phylogenetic tree could better represent the phylogenetic relationship in the acidophilus complex than L-LDH-based tree. They next investigated the evolutions of LDH genes of L. delbrueckii at amino acid level, and found that D-LDH gene in L. delbrueckii is positively selected, possibly a consequence of long-term domestication. They further identified four amino acids that are under positive selection. One of them, V261, is located at the centre of three catalytic active sites, indicating likely functional effects on the enzyme activity. The selection from the domestication process thus provides direction for future engineering of D-LDH. PMID:26243834

  2. Determination of lactate dehydrogenase (LDH) activity in milk by a fluorometric assay.

    PubMed

    Larsen, Torben

    2005-05-01

    Indigenous L-lactate dehydrogenase (LDH) in milk originates mainly from somatic cells, leucocytes and invading microorganisms. Its activity may be used for detection of mastitis. However, existing methods to measure LDH activity in milk both need pretreatment of the samples and still suffer from methodological problems. The present paper describes a fast, reliable method for determination of LDH activity, suitable for milk samples. The method is based on fluorometric determination of enzyme kinetics when L-lactate is converted to pyruvate. The assay uses raw milk without pretreatment and the method is easily adjustable to large-scale analyses on micro assay plates. Detection is based on (straight line) linear response within 4-7 min of initiation of the reaction. A substrate concentration of 35 mM in the reaction mixture was considered to be optimal for the assay. Intra plate assay precision was approx. 6% (CV) and the inter plate precision approx. 10%. Known inhibitors of LDH activity (oxidative direction), i.e., oxalic acid, oxamate, and pyruvate, were tested in different concentrations in order to verify the specificity of the response. The detailed kinetics of samples analysed indicated that the isoenzyme composition may have differed between milk samples, and that this composition may have been altered in high activity samples. PMID:15909687

  3. Cellular prion protein directly interacts with and enhances lactate dehydrogenase expression under hypoxic conditions.

    PubMed

    Ramljak, Sanja; Schmitz, Matthias; Zafar, Saima; Wrede, Arne; Schenkel, Sara; Asif, Abdul R; Carimalo, Julie; Doeppner, Thorsten R; Schulz-Schaeffer, Walter J; Weise, Jens; Zerr, Inga

    2015-09-01

    Although a physiological function of the cellular prion protein (PrP(c)) is still not fully clarified, a PrP(c)-mediated neuroprotection against hypoxic/ischemic insult is intriguing. After ischemic stroke prion protein knockout mice (Prnp(0/0)) display significantly greater lesions as compared to wild-type (WT) mice. Earlier reports suggested an interaction between the glycolytic enzyme lactate dehydrogenase (LDH) and PrP(c). Since hypoxic environment enhances LDH expression levels and compels neurons to rely on lactate as an additional oxidative substrate for energy metabolism, we examined possible differences in LDH protein expression in WT and Prnp(0/0) knockout models under normoxic/hypoxic conditions in vitro and in vivo, as well as in a HEK293 cell line. While no differences are observed under normoxic conditions, LDH expression is markedly increased after 60-min and 90-min of hypoxia in WT vs. Prnp(0/0) primary cortical neurons with concurrent less hypoxia-induced damage in the former group. Likewise, cerebral ischemia significantly increases LDH levels in WT vs. Prnp(0/0) mice with accompanying smaller lesions in the WT group. HEK293 cells overexpressing PrP(c) show significantly higher LDH expression/activity following 90-min of hypoxia as compared to control cells. Moreover, a cytoplasmic co-localization of LDH and PrP(c) was recorded under both normoxic and hypoxic conditions. Interestingly, an expression of monocarboxylate transporter 1, responsible for cellular lactate uptake, increases with PrP(c)-overexpression under normoxic conditions. Our data suggest LDH as a direct PrP(c) interactor with possible physiological relevance under low oxygen conditions. PMID:26024859

  4. Energy landscape of the Michaelis complex of lactate dehydrogenase: relationship to catalytic mechanism.

    PubMed

    Peng, Huo-Lei; Deng, Hua; Dyer, R Brian; Callender, Robert

    2014-03-25

    Lactate dehydrogenase (LDH) catalyzes the interconversion between pyruvate and lactate with nicotinamide adenine dinucleotide (NAD) as a cofactor. Using isotope-edited difference Fourier transform infrared spectroscopy on the "live" reaction mixture (LDH·NADH·pyruvate ⇌ LDH·NAD(+)·lactate) for the wild-type protein and a mutant with an impaired catalytic efficiency, a set of interconverting conformational substates within the pyruvate side of the Michaelis complex tied to chemical activity is revealed. The important structural features of these substates include (1) electronic orbital overlap between pyruvate's C2═O bond and the nicotinamide ring of NADH, as shown from the observation of a delocalized vibrational mode involving motions from both moieties, and (2) a characteristic hydrogen bond distance between the pyruvate C2═O group and active site residues, as shown by the observation of at least four C2═O stretch bands indicating varying degrees of C2═O bond polarization. These structural features form a critical part of the expected reaction coordinate along the reaction path, and the ability to quantitatively determine them as well as the substate population ratios in the Michaelis complex provides a unique opportunity to probe the structure-activity relationship in LDH catalysis. The various substates have a strong variance in their propensity toward on enzyme chemistry. Our results suggest a physical mechanism for understanding the LDH-catalyzed chemistry in which the bulk of the rate enhancement can be viewed as arising from a stochastic search through an available phase space that, in the enzyme system, involves a restricted ensemble of more reactive conformational substates as compared to the same chemistry in solution. PMID:24576110

  5. Energy Landscape of the Michaelis Complex of Lactate Dehydrogenase: Relationship to Catalytic Mechanism

    PubMed Central

    2015-01-01

    Lactate dehydrogenase (LDH) catalyzes the interconversion between pyruvate and lactate with nicotinamide adenine dinucleotide (NAD) as a cofactor. Using isotope-edited difference Fourier transform infrared spectroscopy on the “live” reaction mixture (LDH·NADH·pyruvate ⇌ LDH·NAD+·lactate) for the wild-type protein and a mutant with an impaired catalytic efficiency, a set of interconverting conformational substates within the pyruvate side of the Michaelis complex tied to chemical activity is revealed. The important structural features of these substates include (1) electronic orbital overlap between pyruvate’s C2=O bond and the nicotinamide ring of NADH, as shown from the observation of a delocalized vibrational mode involving motions from both moieties, and (2) a characteristic hydrogen bond distance between the pyruvate C2=O group and active site residues, as shown by the observation of at least four C2=O stretch bands indicating varying degrees of C2=O bond polarization. These structural features form a critical part of the expected reaction coordinate along the reaction path, and the ability to quantitatively determine them as well as the substate population ratios in the Michaelis complex provides a unique opportunity to probe the structure–activity relationship in LDH catalysis. The various substates have a strong variance in their propensity toward on enzyme chemistry. Our results suggest a physical mechanism for understanding the LDH-catalyzed chemistry in which the bulk of the rate enhancement can be viewed as arising from a stochastic search through an available phase space that, in the enzyme system, involves a restricted ensemble of more reactive conformational substates as compared to the same chemistry in solution. PMID:24576110

  6. Automated High Throughput Protein Crystallization Screening at Nanoliter Scale and Protein Structural Study on Lactate Dehydrogenase

    SciTech Connect

    Fenglei Li

    2006-08-09

    The purposes of our research were: (1) To develop an economical, easy to use, automated, high throughput system for large scale protein crystallization screening. (2) To develop a new protein crystallization method with high screening efficiency, low protein consumption and complete compatibility with high throughput screening system. (3) To determine the structure of lactate dehydrogenase complexed with NADH by x-ray protein crystallography to study its inherent structural properties. Firstly, we demonstrated large scale protein crystallization screening can be performed in a high throughput manner with low cost, easy operation. The overall system integrates liquid dispensing, crystallization and detection and serves as a whole solution to protein crystallization screening. The system can dispense protein and multiple different precipitants in nanoliter scale and in parallel. A new detection scheme, native fluorescence, has been developed in this system to form a two-detector system with a visible light detector for detecting protein crystallization screening results. This detection scheme has capability of eliminating common false positives by distinguishing protein crystals from inorganic crystals in a high throughput and non-destructive manner. The entire system from liquid dispensing, crystallization to crystal detection is essentially parallel, high throughput and compatible with automation. The system was successfully demonstrated by lysozyme crystallization screening. Secondly, we developed a new crystallization method with high screening efficiency, low protein consumption and compatibility with automation and high throughput. In this crystallization method, a gas permeable membrane is employed to achieve the gentle evaporation required by protein crystallization. Protein consumption is significantly reduced to nanoliter scale for each condition and thus permits exploring more conditions in a phase diagram for given amount of protein. In addition, evaporation rate can be controlled or adjusted in this method during the crystallization process to favor either nucleation or growing processes for optimizing crystallization process. The protein crystals gotten by this method were experimentally proven to possess high x-ray diffraction qualities. Finally, we crystallized human lactate dehydrogenase 1 (H4) complexed with NADH and determined its structure by x-ray crystallography. The structure of LDH/NADH displays a significantly different structural feature, compared with LDH/NADH/inhibitor ternary complex structure, that subunits in LDH/NADH complex show open conformation or two conformations on the active site while the subunits in LDH/NADH/inhibitor are all in close conformation. Multiple LDH/NADH crystals were obtained and used for x-ray diffraction experiments. Difference in subunit conformation was observed among the structures independently solved from multiple individual LDH/NADH crystals. Structural differences observed among crystals suggest the existence of multiple conformers in solution.

  7. Hypoxically inducible barley lactate dehydrogenase: cDNA cloning and molecular analysis

    SciTech Connect

    Hondred, D. ); Hanson, A.D. Univ. de Montreal, Quebec )

    1990-09-01

    In the roots of barley and other cereals, hypoxia induces a set of five isozymes of L-lactate dehydrogenase (LDH; (S)-lactate:NADH oxidoreductase, EC 1.1.1.27). Biochemical and genetic data indicate that the five LDH isozymes are tetramers that arise from random association of the products of two Ldh loci. To investigate this system, cDNA clones of LDH were isolated from a {lambda}gt11 cDNA library derived from hypoxically treated barley roots. The library was screened with antiserum raised against barley LDH purified {approx}3,000-fold by an improved three-step procedure. Immunopositive clones were rescreened with a cDNA probe synthesized by the polymerase chain reaction using primers modeled from the amino acid sequences of two tryptic LDH peptides. Two types of LDH clones were found. Nucleotide sequence analysis of one representative insert of each type (respectively, 1,305 and 1,166 base pairs) revealed open reading framed encoding 10 peptide fragments of LDH. The 1,305-base-pair insert included the entire coding region of a 356-residue LDH monomer. The nucleotide sequences of the two LDH cDNAs were 92% identical in the coding region, but highly divergent in the 3{prime} noncoding region, and thus probably correspond to the two postulated Ldh loci. The deduced amino acid sequences of the two barley LDHs were 96% identical to each other and very similar to those from vertebrate and bacterial LDHs. RNA blot hybridization showed a single mRNA band of 1.5 kilobases whose level rose about 8-fold in roots during hypoxic induction, as did the level of translatable LDH message.

  8. Low intensity microwave radiation as modulator of the L-lactate dehydrogenase activity.

    PubMed

    Vojisavljevic, Vuk; Pirogova, Elena; Cosic, Irena

    2011-07-01

    In this study, we investigated experimentally the possibility of modulating protein activity by low intensity microwaves by measuring alternations of L: -Lactate Dehydrogenase enzyme (LDH) activity. The LDH enzyme solutions were irradiated by microwaves of the selected frequencies and powers using the Transverse Electro-Magnetic (TEM) cell. The kinetics of the irradiated LDH was measured by continuous monitoring of nicotine adenine dinucleotide, reduced (NADH) absorbance at 340 nm. A comparative analysis of changes in the activity of the irradiated LDH enzyme versus the non-radiated enzyme was performed for the selected frequencies and powers. It was found that LDH activity can be selectively increased only by irradiation at the particular frequencies of 500 MHz [electric field: 0.02 V/m (1.2 × 10⁻⁶ W/m²)-2.1 V/m (1.2 × 10⁻² W/m²)] and 900 MHz [electric field: 0.021-0.21 V/m (1.2 × 10⁻⁴ W/m²)]. Based on results obtained it was concluded that LDH enzyme activity can be modulated by specific frequencies of low power microwave radiation. This finding can serve to support the hypothesis that low intensity microwaves can induce non-thermal effects in bio-molecules. PMID:21308416

  9. Gene Expression Variation in Duplicate Lactate dehydrogenase Genes: Do Ecological Species Show Distinct Responses?

    PubMed Central

    Cristescu, Melania E.; Demiri, Bora; Altshuler, Ianina; Crease, Teresa J.

    2014-01-01

    Lactate dehydrogenase (LDH) has been shown to play an important role in adaptation of several aquatic species to different habitats. The genomes of Daphnia pulex, a pond species, and Daphnia pulicaria, a lake inhabitant, encode two L-LDH enzymes, LDHA and LDHB. We estimated relative levels of Ldh gene expression in these two closely related species and their hybrids in four environmental settings, each characterized by one of two temperatures (10°C or 20°C), and one of two concentrations of dissolved oxygen (DO; 6.5–7 mg/l or 2–3 mg/l). We found that levels of LdhA expression were 4 to 48 times higher than LdhB expression (p<0.005) in all three groups (the two parental species and hybrids). Moreover, levels of LdhB expression differed significantly (p<0.05) between D. pulex and D. pulicaria, but neither species differed from the hybrid. Consistently higher expression of LdhA relative to LdhB in both species and the hybrid suggests that the two isozymes could be performing different functions. No significant differences in levels of gene expression were observed among the four combinations of temperature and dissolved oxygen (p>0.1). Given that Daphnia dwell in environments characterized by fluctuating conditions with long periods of low dissolved oxygen concentration, we suggest that these species could employ regulated metabolic depression to survive in such environments. PMID:25080082

  10. Gene expression variation in duplicate lactate dehydrogenase genes: do ecological species show distinct responses?

    PubMed

    Cristescu, Melania E; Demiri, Bora; Altshuler, Ianina; Crease, Teresa J

    2014-01-01

    Lactate dehydrogenase (LDH) has been shown to play an important role in adaptation of several aquatic species to different habitats. The genomes of Daphnia pulex, a pond species, and Daphnia pulicaria, a lake inhabitant, encode two L-LDH enzymes, LDHA and LDHB. We estimated relative levels of Ldh gene expression in these two closely related species and their hybrids in four environmental settings, each characterized by one of two temperatures (10°C or 20°C), and one of two concentrations of dissolved oxygen (DO; 6.5-7 mg/l or 2-3 mg/l). We found that levels of LdhA expression were 4 to 48 times higher than LdhB expression (p<0.005) in all three groups (the two parental species and hybrids). Moreover, levels of LdhB expression differed significantly (p<0.05) between D. pulex and D. pulicaria, but neither species differed from the hybrid. Consistently higher expression of LdhA relative to LdhB in both species and the hybrid suggests that the two isozymes could be performing different functions. No significant differences in levels of gene expression were observed among the four combinations of temperature and dissolved oxygen (p>0.1). Given that Daphnia dwell in environments characterized by fluctuating conditions with long periods of low dissolved oxygen concentration, we suggest that these species could employ regulated metabolic depression to survive in such environments. PMID:25080082

  11. The enzymatic reaction catalyzed by lactate dehydrogenase exhibits one dominant reaction path

    NASA Astrophysics Data System (ADS)

    Masterson, Jean E.; Schwartz, Steven D.

    2014-10-01

    Enzymes are the most efficient chemical catalysts known, but the exact nature of chemical barrier crossing in enzymes is not fully understood. Application of transition state theory to enzymatic reactions indicates that the rates of all possible reaction paths, weighted by their relative probabilities, must be considered in order to achieve an accurate calculation of the overall rate. Previous studies in our group have shown a single mechanism for enzymatic barrier passage in human heart lactate dehydrogenase (LDH). To ensure that this result was not due to our methodology insufficiently sampling reactive phase space, we implement high-perturbation transition path sampling in both microcanonical and canonical regimes for the reaction catalyzed by human heart LDH. We find that, although multiple, distinct paths through reactive phase space are possible for this enzymatic reaction, one specific reaction path is dominant. Since the frequency of these paths in a canonical ensemble is inversely proportional to the free energy barriers separating them from other regions of phase space, we conclude that the rarer reaction paths are likely to have a negligible contribution. Furthermore, the non-dominate reaction paths correspond to altered reactive conformations and only occur after multiple steps of high perturbation, suggesting that these paths may be the result of non-biologically significant changes to the structure of the enzymatic active site.

  12. Lactate Dehydrogenase Is an Important Prognostic Indicator for Hepatocellular Carcinoma after Partial Hepatectomy12

    PubMed Central

    Zhang, Jing-Ping; Wang, Hong-Bo; Lin, Yue-Hao; Xu, Jing; Wang, Jun; Wang, Kai; Liu, Wan-Li

    2015-01-01

    Preoperative serum lactate dehydrogenase (LDH) has been used as a prognostic indicator for patients with hepatocellular carcinoma (HCC) treated with sorafenib or undergoing transcatheter arterial chemoembolization, but its significance in predicting survival of HCC patients who received curative resection remains undefined. A total of 683 patients with histopathologically confirmed HCC were enrolled in this study. The prognostic significance of preoperative serum LDH was determined by Kaplan-Meier analysis and a Cox proportional hazards regression model. The association between the preoperative serum LDH and clinicopathological parameters was evaluated by the χ2 test or linear regression analysis when appropriate. Higher preoperative serum LDH level was associated with worse prognosis. In a multivariate Cox proportional hazards analysis, the preoperative serum LDH level could predict overall survival and recurrence independently. Higher preoperative serum LDH level is associated with the elevated serum alpha-fetoprotein, the presence of hepatitis B surface antigen, larger tumor size, the presence of macrovascular invasion, the advanced tumor–lymph node–metastasis stage, worse tumor differentiation, and Child-Pugh B. Preoperative serum LDH level was an inexpensive, simple, convenient, and routinely measured biomarker exhibiting a potential to select patients at high risk with poor clinical outcome for appropriate treatment strategies. PMID:26692531

  13. An atomic-resolution view of neofunctionalization in the evolution of apicomplexan lactate dehydrogenases

    PubMed Central

    Boucher, Jeffrey I; Jacobowitz, Joseph R; Beckett, Brian C; Classen, Scott; Theobald, Douglas L

    2014-01-01

    Malate and lactate dehydrogenases (MDH and LDH) are homologous, core metabolic enzymes that share a fold and catalytic mechanism yet possess strict specificity for their substrates. In the Apicomplexa, convergent evolution of an unusual LDH from MDH produced a difference in specificity exceeding 12 orders of magnitude. The mechanisms responsible for this extraordinary functional shift are currently unknown. Using ancestral protein resurrection, we find that specificity evolved in apicomplexan LDHs by classic neofunctionalization characterized by long-range epistasis, a promiscuous intermediate, and few gain-of-function mutations of large effect. In canonical MDHs and LDHs, a single residue in the active-site loop governs substrate specificity: Arg102 in MDHs and Gln102 in LDHs. During the evolution of the apicomplexan LDH, however, specificity switched via an insertion that shifted the position and identity of this ‘specificity residue’ to Trp107f. Residues far from the active site also determine specificity, as shown by the crystal structures of three ancestral proteins bracketing the key duplication event. This work provides an unprecedented atomic-resolution view of evolutionary trajectories creating a nascent enzymatic function. DOI: http://dx.doi.org/10.7554/eLife.02304.001 PMID:24966208

  14. An atomic-resolution view of neofunctionalization in the evolution of apicomplexan lactate dehydrogenases.

    PubMed

    Boucher, Jeffrey I; Jacobowitz, Joseph R; Beckett, Brian C; Classen, Scott; Theobald, Douglas L

    2014-01-01

    Malate and lactate dehydrogenases (MDH and LDH) are homologous, core metabolic enzymes that share a fold and catalytic mechanism yet possess strict specificity for their substrates. In the Apicomplexa, convergent evolution of an unusual LDH from MDH produced a difference in specificity exceeding 12 orders of magnitude. The mechanisms responsible for this extraordinary functional shift are currently unknown. Using ancestral protein resurrection, we find that specificity evolved in apicomplexan LDHs by classic neofunctionalization characterized by long-range epistasis, a promiscuous intermediate, and few gain-of-function mutations of large effect. In canonical MDHs and LDHs, a single residue in the active-site loop governs substrate specificity: Arg102 in MDHs and Gln102 in LDHs. During the evolution of the apicomplexan LDH, however, specificity switched via an insertion that shifted the position and identity of this 'specificity residue' to Trp107f. Residues far from the active site also determine specificity, as shown by the crystal structures of three ancestral proteins bracketing the key duplication event. This work provides an unprecedented atomic-resolution view of evolutionary trajectories creating a nascent enzymatic function. PMID:24966208

  15. Quick histochemical staining method for measuring lactate dehydrogenase C4 activity in human spermatozoa.

    PubMed

    Cui, Zhaolei; Chen, Liangyuan; Liu, Yaohua; Zeng, Zhangxin; Lan, Fenghua

    2015-04-01

    The enzyme activity of lactate dehydrogenase C4 (LDH-C4, due to tetrameric nature of C-subunit) has been proposed as an important parameter in evaluating sperm motility and semen quality. A novel histochemical staining method for detecting LDH-C4 activity in human spermatozoa is described in this report. The staining working solution comprises sodium 2-hydroxybutyrate (an affinity substrate of LDH-C4), nitrotetrazolium blue chloride (NBT), nicotinamide adenine dinucleotide (NAD) and naphthol blue. The positive products were purple black lumps concentrated in the neck segment of the spermatozoa and weakly in the middle piece. A normal reference range for the integral enzyme activity was constructed from 120 healthy males based upon the scoring criteria. The study further compared the staining method with the routine spectrophotometry technique in terms of the results of 96 cases with infertile status. Moreover, we found the down-regulated LDH-C4 expression was significantly correlated with the lowered enzyme activity (r=0.865, P=0.000). Our data suggest that the histochemical staining method hallmarks a relatively high accuracy and may be a better alternative for measuring LDH-C4 activity in human spermatozoa. PMID:25795631

  16. Glycoconjugates Influence Caspase Release and Minimize Production of Lactate Dehydrogenase upon Pathogen Exposure

    NASA Astrophysics Data System (ADS)

    Eassa, Souzan; Tarasenko, Olga

    2010-04-01

    Many pathogens stimulate cell death of immune cells while promoting survival of pathogens. Early cell death is characterized by the release of mediators, namely Caspases (Cas). Infections caused by pathogens can be eradicated if immune cells could resist cell death and kill pathogens upon exposure. In this research, we studied whether glycoconjugates (GCs) influence Cas release and cytotoxicity upon pathogen damage. GC1 and GC3 constituted samples studied principally. Bacterial spores were used as a pathogen model. GC effects were determined "prior to," "during," and "following" pathogen exposure throughout phagocytosis. Cytotoxic damage was assessed by measuring lactate dehydrogenase (LDH) production. Our data show that GC3 was more effective than GC1 during phagocytosis. GC3 controls Cas release under all three exposure conditions. Minimum production of LDH was noticed in the "following" exposure condition compared to the "prior to" and "during" exposure conditions for GC1 and GC3. The present study provided the selection method of GC ligands bearing anti-cytotoxic and anti-apoptotic properties.

  17. Quantification of lactate-dehydrogenase and cell viability in postmortem human dental pulp.

    PubMed

    Caviedes-Bucheli, Javier; Avendao, Nuvia; Gutierrez, Rhina; Hernndez, Sandra; Moreno, Gloria Cristina; Romero, Mara Consuelo; Muoz, Hugo Roberto

    2006-03-01

    Understanding pulp repair and regeneration requires being familiar with this tissue's behavior under extreme conditions, such as postmortem state where an abrupt interruption of tissue blood supply occurs. The purpose of this study was to quantify cell viability and the amount of lactate-dehydrogenase (LDH) expressed in human pulp tissue 6, 12, and 24 hours postmortem to establish how long dental pulp remains viable after death. Pulp samples were obtained from 14 unidentified corpses of people who had received lethal injuries in car accidents or from gunshot wounds; they had at least three caries- and restoration-free incisors. Half of each sample was used for determining cell viability at three different time intervals. The rest of each sample was used for quantifying LDH expression at the same time intervals. Another 14 pulp samples were obtained from live patients' healthy premolars where extraction was indicated for orthodontic reasons to assess normal LDH value in pulp tissue. The results showed cell viability decreasing from 89 to 68 to 41% measured 6, 12, and 24 hours postmortem, respectively. LDH expression in healthy pulps was 246 U/mg pulp weight. Expression increased after death from 249 U/mg at 6 hours to 337 U/mg at 12 hours. LDH expression decreased to 131 U/mg 24 hours postmortem. These findings are valuable in understanding dental pulp survival capability under extreme conditions that may have important clinical significance in terms of repair and regeneration. PMID:16500222

  18. SYNAPTOSOMAL LACTATE DEHYDROGENASE ISOENZYME COMPOSITION IS SHIFTED TOWARD AEROBIC FORMS IN PRIMATE BRAIN EVOLUTION

    PubMed Central

    Duka, Tetyana; Anderson, Sarah M.; Collins, Zachary; Raghanti, Mary Ann; Ely, John J.; Hof, Patrick R.; Wildman, Derek E.; Goodman, Morris; Grossman, Lawrence I.; Sherwood, Chet C.

    2014-01-01

    With the evolution of a relatively large brain size in haplorhine primates (i.e., tarsiers, monkeys, apes and humans), there have been associated changes in the molecular machinery that delivers energy to the neocortex. Here we investigated variation in lactate dehydrogenase (LDH) expression and isoenzyme composition of the neocortex and striatum in primates using quantitative Western blotting and isoenzyme analysis of total homogenates and synaptosomal fractions. Analysis of isoform expression revealed that LDH in the synaptosomal fraction from both forebrain regions shifted towards a predominance of the heart-type, aerobic isoforms, LDHB, among haplorhines as compared to strepsirrhines (i.e., lorises and lemurs), while in total homogenate of neocortex and striatum there was no significant difference in the LDH isoenzyme composition between the primate suborders. The largest increase occurred in synapse-associated LDH-B expression in the neocortex, displaying an especially remarkable elevation in the ratio of LDH-B to LDH-A in humans. The phylogenetic variation in LDH-B to LDH-A ratio was correlated with species typical brain mass, but not encephalization quotient. A significant LDHB increase in the sub-neuronal fraction from haplorhine neocortex and striatum suggests a relatively higher rate of aerobic glycolysis that is linked to synaptosomal mitochondrial metabolism. Our results indicate that there is differential composition of LDH isoenzymes and metabolism in synaptic terminals that evolved in primates to meet increased energy requirements in association with brain enlargement. PMID:24686273

  19. Synaptosomal lactate dehydrogenase isoenzyme composition is shifted toward aerobic forms in primate brain evolution.

    PubMed

    Duka, Tetyana; Anderson, Sarah M; Collins, Zachary; Raghanti, Mary Ann; Ely, John J; Hof, Patrick R; Wildman, Derek E; Goodman, Morris; Grossman, Lawrence I; Sherwood, Chet C

    2014-01-01

    With the evolution of a relatively large brain size in haplorhine primates (i.e. tarsiers, monkeys, apes, and humans), there have been associated changes in the molecular machinery that delivers energy to the neocortex. Here we investigated variation in lactate dehydrogenase (LDH) expression and isoenzyme composition of the neocortex and striatum in primates using quantitative Western blotting and isoenzyme analysis of total homogenates and synaptosomal fractions. Analysis of isoform expression revealed that LDH in synaptosomal fractions from both forebrain regions shifted towards a predominance of the heart-type, aerobic isoform LDH-B among haplorhines as compared to strepsirrhines (i.e. lorises and lemurs), while in the total homogenate of the neocortex and striatum there was no significant difference in LDH isoenzyme composition between the primate suborders. The largest increase occurred in synapse-associated LDH-B expression in the neocortex, with an especially remarkable elevation in the ratio of LDH-B/LDH-A in humans. The phylogenetic variation in the ratio of LDH-B/LDH-A was correlated with species-typical brain mass but not the encephalization quotient. A significant LDH-B increase in the subneuronal fraction from haplorhine neocortex and striatum suggests a relatively higher rate of aerobic glycolysis that is linked to synaptosomal mitochondrial metabolism. Our results indicate that there is a differential composition of LDH isoenzymes and metabolism in synaptic terminals that evolved in primates to meet increased energy requirements in association with brain enlargement. PMID:24686273

  20. Regulation of cell growth and apoptosis through lactate dehydrogenase C over-expression in Chinese hamster ovary cells.

    PubMed

    Fu, Tuo; Zhang, Cunchao; Jing, Yu; Jiang, Cheng; Li, Zhenhua; Wang, Shengyu; Ma, Kai; Zhang, Dapeng; Hou, Sheng; Dai, Jianxin; Kou, Geng; Wang, Hao

    2016-06-01

    Lactate has long been credited as a by-product, which jeopardizes cell growth and productivity when accumulated over a certain concentration during the manufacturing process of therapeutic recombinant proteins by Chinese hamster ovary (CHO) cells. A number of efforts to decrease the lactate concentration have been developed; however, the accumulation of lactate is still a critical issue by the late stage of fed-batch culture. Therefore, a lactate-tolerant cell line was developed through over-expression of lactate dehydrogenase C (LDH-C). In fed-batch culture, sodium lactate or sodium pyruvate was supplemented into the culture medium to simulate the environment of lactate accumulation, and LDH-C over-expression increased the highest viable cell density by over 30 and 50 %, respectively, on day 5, meanwhile the viability was also improved significantly since day 5 compared with that of the control. The percentages of cells suffering early and late apoptosis decreased by 3.2 to 12.5 and 2.0 to 4.3 %, respectively, from day 6 onwards in the fed-batch culture when 40 mM sodium pyruvate was added compared to the control. The results were confirmed by mitochondrial membrane potential assay. In addition, the expression of cleaved caspases 3 and 7 decreased in cells over-expressing LDH-C, suggesting the mitochondrial pathway was involved in the LDH-C regulated anti-apoptosis. In conclusion, a novel cell line with higher lactate tolerance, lowered lactate production, and alleviated apoptosis response was developed by over-expression of LDH-C, which may potentially represent an efficient and labor-saving approach in generating recombinant proteins. PMID:26841889

  1. Preliminary Study on Serum Lactate Dehydrogenase (LDH)-Prognostic Biomarker in Carcinoma Breast

    PubMed Central

    Gandhe, Mahendra Bhauraoji; Gupta, Dilip; Reddy, M.V.R.

    2016-01-01

    Introduction Serum Lactate Dehydrogenase (LDH) is one of the biochemical markers for breast cancer. Serum LDH is enzyme required for anaerobic glycolysis. One of its isoenzyme is increased in breast cancer due to up-regulation in its gene. It leads to increase in serum LDH level in breast cancer patients. Serum LDH is economical, easily available and easy to estimate. Aim In the present study, we evaluated the LDH levels in circulation of newly diagnosed patients of breast cancer and tried to correlate it with different TNM staging of carcinoma breast before interventions and after adjuvant therapy of these patients. Materials and Methods This prospective study was done on 83 diagnosed patients of breast cancer was conducted among poor patients in rural area. This study was conducted in the Department of Surgery between October 2008 to October 2010, at MGIMS, Sevagram, Maharashtra, a rural medical college located in Central India. Out of total 83 participants, 10 participants were having adverse events following surgery and remaining 73 participants were without adverse events following surgery. The significant difference in serum LDH levels between two groups, with and without adverse surgical outcome was calculated by Mann-Whitney U test. Results Patients with higher clinical TNM staging were having higher serum LDH levels. The serum LDH levels at sixth months following surgery showed a trend of statistically significant difference between patients with and without adverse events. As increased serum LDH levels in breast cancer patients shows poor prognosis, surgical outcome or advanced metastases. Conclusion Serum LDH monitoring can be used as a prognostic biomarker in patients of breast cancer. For confirmation of this finding, we require further more studies on larger sample size and long-term follow-up in patients specifically with higher serum LDH levels.

  2. Plasmodium falciparum and Plasmodium vivax specific lactate dehydrogenase: genetic polymorphism study from Indian isolates.

    PubMed

    Keluskar, Priyadarshan; Singh, Vineeta; Gupta, Purva; Ingle, Sanjay

    2014-08-01

    Control and eradication of malaria is hindered by the acquisition of drug resistance by Plasmodium species. This has necessitated a persistent search for novel drugs and more efficient targets. Plasmodium species specific lactate dehydrogenase is one of the potential therapeutic and diagnostic targets, because of its indispensable role in endoerythrocytic stage of the parasite. A target molecule that is highly conserved in the parasite population can be more effectively used in diagnostics and therapeutics, hence, in the present study polymorphism in PfLDH (Plasmodiumfalciparum specific LDH) and PvLDH (Plasmodiumvivax specific LDH) genes was analyzed using PCR-single strand confirmation polymorphism (PCR-SSCP) and sequencing. Forty-six P. falciparum and thirty-five P. vivax samples were screened from different states of India. Our findings have revealed presence of a single PfLDH genotype and six PvLDH genotypes among the studied samples. Interestingly, along with synonymous substitutions, nonsynonymous substitutions were reported to be present for the first time in the PvLDH genotypes. Further, through amino acid sequence alignment and homology modeling studies we observed that the catalytic residues were conserved in all PvLDH genotypes and the nonsynonymous substitutions have not altered the enzyme structure significantly. Evolutionary genetics studies have confirmed that PfLDH and PvLDH loci are under strong purifying selection. Phylogenetic analysis of the pLDH gene sequences revealed that P. falciparum compared to P. vivax, has recent origin. The study therefore supports PfLDH and PvLDH as suitable therapeutic and diagnostic targets as well as phylogenetic markers to understand the genealogy of malaria species. PMID:24953504

  3. Regulation of the Activity of Lactate Dehydrogenases from Four Lactic Acid Bacteria*

    PubMed Central

    Feldman-Salit, Anna; Hering, Silvio; Messiha, Hanan L.; Veith, Nadine; Cojocaru, Vlad; Sieg, Antje; Westerhoff, Hans V.; Kreikemeyer, Bernd; Wade, Rebecca C.; Fiedler, Tomas

    2013-01-01

    Despite high similarity in sequence and catalytic properties, the l-lactate dehydrogenases (LDHs) in lactic acid bacteria (LAB) display differences in their regulation that may arise from their adaptation to different habitats. We combined experimental and computational approaches to investigate the effects of fructose 1,6-bisphosphate (FBP), phosphate (Pi), and ionic strength (NaCl concentration) on six LDHs from four LABs studied at pH 6 and pH 7. We found that 1) the extent of activation by FBP (Kact) differs. Lactobacillus plantarum LDH is not regulated by FBP, but the other LDHs are activated with increasing sensitivity in the following order: Enterococcus faecalis LDH2 ≤ Lactococcus lactis LDH2 < E. faecalis LDH1 < L. lactis LDH1 ≤ Streptococcus pyogenes LDH. This trend reflects the electrostatic properties in the allosteric binding site of the LDH enzymes. 2) For L. plantarum, S. pyogenes, and E. faecalis, the effects of Pi are distinguishable from the effect of changing ionic strength by adding NaCl. 3) Addition of Pi inhibits E. faecalis LDH2, whereas in the absence of FBP, Pi is an activator of S. pyogenes LDH, E. faecalis LDH1, and L. lactis LDH1 and LDH2 at pH 6. These effects can be interpreted by considering the computed binding affinities of Pi to the catalytic and allosteric binding sites of the enzymes modeled in protonation states corresponding to pH 6 and pH 7. Overall, the results show a subtle interplay among the effects of Pi, FBP, and pH that results in different regulatory effects on the LDHs of different LABs. PMID:23720742

  4. Analysis of the rat lactate dehydrogenase A subunit gene promoter/regulatory region.

    PubMed Central

    Short, M L; Huang, D; Milkowski, D M; Short, S; Kunstman, K; Soong, C J; Chung, K C; Jungmann, R A

    1994-01-01

    The rat lactate dehydrogenase (LDH) A subunit gene promoter contains a putative AP-1 binding site at -295/-289 bp, two consensus Sp1 binding sites at -141/-136 bp and -103/-98 bp, and a single copy of a consensus cyclic AMP-responsive element (CRE) at -48 to -41 bp upstream of the transcription initiation site. Additionally, an as yet unidentified silencer element is located within the -1173/-830 bp 5'-flanking region. Transient transfection analyses of a -1173/+25 bp LDH A-chLoramphenicol acetyltransferase fusion gene has indicated a complete inability of the promoter fragment to direct basal or forskolin-induced transcription. Deletion of the -1173/-830 bp sequence restored basal and cyclic AMP (cAMP)-inducible activity. Point mutations in the Sp1 binding sites of a -830/+25 bp promoter fragment reduced basal but not the relative degree of cAMP-inducible activity. cAMP-regulated transcriptional activity was dependent upon an 8 bp CRE, -TGACGTCA-, located at the -48/-41 bp upstream region. Mutations in the CRE abolished cAMP-mediated induction and reduced basal activity by about 65%. The CRE binds a 47 kDa protein which has previously been identified as CRE binding protein (CREB)-327, an isoform of the activating transcription factor/CREB transcription factor gene family. Co-transfection of a vector that expresses the catalytic subunit of cAMP-dependent protein kinase stimulates LDH A subunit promoter activity suggesting that cAMP induces LDH A subunit gene expression through phosphorylative modification of CREB-327. This study emphasizes a fundamental role of several modules including Sp1 and CREB binding sites in regulating basal and cAMP-mediated transcriptional activity of the LDH A gene. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 PMID:7998973

  5. The effects of season and temperature on D-lactate dehydrogenase, pyruvate kinase and arginine kinase in the foot of Helix pomatia L.

    PubMed

    Wieser, W; Wright, E

    1979-04-01

    The effects of pH, season, environmental and experimental temperatures on the activities and kinetic parameters of D-lactate dehydrogenase, pyruvate kinase and arginine kinase from the foot of the pulmonate snail Helix pomatia were analyzed. Both in phosphate and Tris buffers D-lactate dehydrogenase was the enzyme with the most acid maximum, arginine kinase that with the most alkaline, whilst pyruvate kinase occupied an intermediate position. Pyruvate kinase activity, measured at 20 degrees C, was positively correlated with the environmental temperature at the moment of collecting the animal, whereas neither arginine kinase nor D-lactate dehydrogenase showed such a relationship. A seasonal study based on approximately 100 specimens established that arginine kinase activity remained the same throughout the year. Pyruvate kinase activity was slightly lower, and D-lactate dehydrogenase activity significantly higher, in winter than in summer animals. Snails subjected in spring to a short warm-up period before enzyme extraction showed extreme variability and some extraordinarily high values of pyruvate kinase activity, suggesting that either season or elevated temperature may have an immediate effect on the activity of this enzyme. Individual variability of all three enzymes ranges from 300 to 400%. The activities of pyruvate kinase and D-lactate dehydrogenase are strongly correlated in summer, forming a "constant-proportion-group", whereas in winter, with D-lactate dehydrogenase activity increasing and pyruvate kinase activity decreasing these two enzymes become "uncoupled". The Km value of pyruvate kinase is independent of experimental temperature between 10 and 25 degrees C, whereas that of D-lactate dehydrogenase and arginine kinase increases about three-fold within this range. Thus the temperature relationship of a single enzymic reaction cannot be used as an arguemnt for or against the occurrence of temperature compensation of whole animal metabolism. The possibility of modulation of enzyme activity by environmental temperature is discussed. PMID:35457

  6. A lactate biosensor based on lactate dehydrogenase/nictotinamide adenine dinucleotide (oxidized form) immobilized on a conducting polymer/multiwall carbon nanotube composite film.

    PubMed

    Rahman, M M; Shiddiky, Muhammad J A; Rahman, Md Aminur; Shim, Yoon-Bo

    2009-01-01

    An amperometric lactate biosensor was developed based on a conducting polymer, poly-5,2'-5',2''-terthiophene-3'-carboxylic acid (pTTCA), and multiwall carbon nanotube (MWNT) composite on a gold electrode. Lactate dehydrogenase (LDH) and the oxidized form of nicotinamide adenine dinucleotide (NAD(+)) were subsequently immobilized onto the pTTCA/MWNT composite film. The modified electrode was characterized by quartz crystal microbalance (QCM), scanning electron microscopy (SEM), and electrochemical experiments. The detection signal was amplified by the pTTCA/MWNT assembly onto which a sufficient amount of enzyme was immobilized and stabilized by the covalent bond formation between the amine groups of enzyme and the carboxylic acid groups of the pTTCA/MWNT film. Experimental parameters affecting the sensor responses, such as applied potential, pH, and temperature, were assessed and optimized. Analytical performances and dynamic ranges of the sensor were determined, and the results showed that the sensitivity, stability, and reproducibility of the sensor improved significantly using pTTCA/MWNT composite film. The calibration plot was linear (r(2)=0.9995) over the range of 5 to 90 microM. The sensitivity was approximately 0.0106 microA/microM, with a detection limit of 1 microM, based on a signal/noise ratio of 3. The applicability of the sensor for the analysis of l-lactate concentration in commercial milk and human serum samples was demonstrated successfully. PMID:18851940

  7. Effects of temperature acclimation on lactate dehydrogenase of cod (Gadus morhua): genetic, kinetic and thermodynamic aspects.

    PubMed

    Zakhartsev, Maxim; Johansen, Torild; Prtner, Hans O; Blust, Ronny

    2004-01-01

    The aim of this study was to determine the effects of seasonal temperature variation on the functional properties of lactate dehydrogenase (LDH) from white muscle and liver of Norwegian coastal cod (Gadus morhua) and the possible relevance of LDH allelic variability for thermal acclimation. Two groups of fishes were acclimated to 4 degrees C or 12 degrees C for one year. Polymorphism was observed in only one (Ldh-B) of the three Ldh loci expressed in cod liver and/or muscle. Isozyme expression remained unchanged regardless of acclimation temperature (T(A)). The products of locus Ldh-B comprise only 14-19% (depending on the tissue) of total LDH activities and, consequently, differences between phenotypes are negligible in terms of their effect on LDH total performance. No kinetic (, V(max)) or thermodynamic (E(a), DeltaG) differences were found among Ldh-B phenotypes. Clear kinetic differences were observed between LDH isoforms in the two tissues. However, the Arrhenius activation energy (E(a)) for pyruvate reduction was the same for both tissues (E(a)=47 kJ mol(-1)) at T(A)=12 degrees C. Factors T(A), tissue and phenotype did not reveal a significant effect on the Gibbs free energy change (DeltaG) of the reaction (55.5 kJ mol(-1)). However, at T(A)=4 degrees C, the E(a) was increased (E(a)=53-56 kJ mol(-1)) and the temperature dependence of the constant of substrate inhibition for pyruvate () decreased in both muscle and liver. In conclusion, the strategies of LDH adjustment to seasonal temperature variations in cod involve changes in LDH concentration (quantitative), adjustment of thermodynamic (E(a)) and kinetic () properties of the LDH (modulative) but not the expression of alternative isoforms (qualitative). We assume that the observed increase in E(a) and the decrease of temperature dependence of at low T(A) is the result of structural changes of the LDH molecule (temperature-driven protein folding). We propose a new mechanism of metabolic compensation of seasonal temperature variations - cold acclimation results in changes in the kinetic and thermodynamic properties of LDH in a way that favours aerobic metabolism through reduction of the competition of LDH for pyruvate in normoxic conditions. PMID:14638837

  8. The use of ternary complexes to study ionizations and isomerizations during catalysis by lactate dehydrogenase*

    PubMed Central

    Holbrook, J. John; Stinson, Robert A.

    1973-01-01

    1. The binding of oxamate to pig heart and pig muscle isoenzymes of lactate dehydrogenase in the presence of NADH was studied by fluorescence titration. The dissociation constant of oxamate from the heart enzyme complex is 3μm and from the muscle isoenzyme 25μm at pH5. These values quantitatively increase with pH as predicted if oxamate can bind only to the enzyme–NADH complex if a group with pK6.9 is protonated. There are four non-interacting oxamate-binding sites per tetramer. 2. o-Nitrophenylpyruvate is a poor substrate for both isoenzymes but has a reasonable affinity to the heart isoenzyme. Initially, it forms an enzyme–NADH–substrate complex, which can be detected either by protein-fluorescence quenching or by NADH-fluorescence quenching. The pH-dependence of the dissociation constant of nitrophenylpyruvate also shows that this ternary complex can only form if a group with pK6.8 is protonated. Taken with the results of chemical-modification experiments, these results allow the pK of 6.8 to be assigned to a system probably involving the imidazole side chain of histidine-195. Formation of a ternary complex from a binary one at pH8 is predicted to result in a proton being taken up from solution. 3. Isotope-effect studies with NADH and its deuterium analogue show that the rapidly formed ternary complex with o-nitrophenylpyruvate slowly isomerizes to give an active ternary complex, which then rapidly decomposes to NAD+. The isomerization is pH-independent, and it is suggested that histidine-195 is still protonated in the activated ternary complex, which is present before hydride transfer. 4. All four subunits of the enzyme are kinetically equivalent with respect to the oxidation of bound NADH by o-nitrophenylpyruvate. 5. A partial mechanism for the enzyme is described which emphasizes the isomerizations and ionizations involved in forming the reduced ternary complex at pH6 and 8. PMID:4352914

  9. Effect of the inactivation of lactate dehydrogenase, ethanol dehydrogenase, and phosphotransacetylase on 2,3-butanediol production in Klebsiella pneumoniae strain

    PubMed Central

    2014-01-01

    Background 2,3-Butanediol (2,3-BD) is a high-value chemical usually produced petrochemically but which can also be synthesized by some bacteria. To date, Klebsiella pneumoniae is the most powerful 2,3-BD producer which can utilize a wide range of substrates. However, many by-products are also produced by K. pneumoniae, such as ethanol, lactate, and acetate, which negatively regulate the 2,3-BD yield and increase the costs of downstream separation and purification. Results In this study, we constructed K. pneumoniae mutants with lactate dehydrogenase (LDH), acetaldehyde dehydrogenase (ADH), and phosphotransacetylase (PTA) deletion individually by suicide vector conjugation. These mutants showed different behavior of production formation. Knock out of ldhA had little influence on the yield of 2,3-BD, whereas knock out of adhE or pta significantly improved the formation of 2,3-BD. The accumulation of the intermediate of 2,3-BD biosynthesis, acetoin, was decreased in all the mutants. The mutants were then tested in five different carbon sources and increased 2,3-BD was observed. Also a double mutant strain with deletion of adhE and ldhA was constructed which resulted in accelerated fermentation and higher 2,3-BD production. In fed-batch culture this strain achieved more than 100 g/L 2,3-BD from glucose with a relatively high yield of 0.49 g/g. Conclusion 2,3-BD production was dramatically improved with the inactivation of adhE and pta. The inactivation of ldhA could advance faster cell growth and shorter fermentation time. The double mutant strain with deletion of adhE and ldhA resulted in accelerated fermentation and higher 2,3-BD production. These results provide new insights for industrial production of 2,3-BD by K. pneumoniae. PMID:24669952

  10. Production of optically pure L-phenyllactic acid by using engineered Escherichia coli coexpressing L-lactate dehydrogenase and formate dehydrogenase.

    PubMed

    Zheng, Zhaojuan; Zhao, Mingyue; Zang, Ying; Zhou, Ying; Ouyang, Jia

    2015-08-10

    L-Phenyllactic acid (L-PLA) is a novel antiseptic agent with broad and effective antimicrobial activity. In addition, L-PLA has been used for synthesis of poly(phenyllactic acid)s, which exhibits better mechanical properties than poly(lactic acid)s. However, the concentration and optical purity of L-PLA produced by native microbes was rather low. An NAD-dependent L-lactate dehydrogenase (L-nLDH) from Bacillus coagulans NL01 was confirmed to have a good ability to produce L-PLA from phenylpyruvic acid (PPA). In the present study, l-nLDH gene and formate dehydrogenase gene were heterologously coexpressed in Escherichia coli. Through two coupled reactions, 79.6mM l-PLA was produced from 82.8mM PPA in 40min and the enantiomeric excess value of L-PLA was high (>99%). Therefore, this process suggested a promising alternative for the production of chiral l-PLA. PMID:26008622

  11. Disruption of lactate dehydrogenase and alcohol dehydrogenase for increased hydrogen production and its effect on metabolic flux in Enterobacter aerogenes.

    PubMed

    Zhao, Hongxin; Lu, Yuan; Wang, Liyan; Zhang, Chong; Yang, Cheng; Xing, Xinhui

    2015-10-01

    Hydrogen production by Enterobacter aerogenes from glucose was enhanced by deleting the targeted ldhA and adh genes responsible for two NADH-consuming pathways which consume most NADH generated from glycolysis. Compared with the wild-type, the hydrogen yield of IAM1183-ΔldhA increased 1.5 fold. Metabolic flux analysis showed both IAM1183-ΔldhA and IAM1183-Δadh exhibited significant changes in flux, including enhanced flux towards the hydrogen generation. The lactate production of IAM1183-ΔldhA significantly decreased by 91.42%, while the alcohol yield of IAM1183-Δadh decreased to 30%. The mutant IAM1183-ΔldhA with better hydrogen-producing performance was selected for further investigation in a 5-L fermentor. The hydrogen production of IAM1183-ΔldhA was 2.3 times higher than the wild-type. Further results from the fermentation process showed that the pH decreased to 5.39 levels, then gradually increased to 5.96, indicating that some acidic metabolites might be degraded or uptaken by cells. PMID:26188552

  12. 220 MHz Proton Nuclear Magnetic Resonance Study of the Interaction between Chicken M4 Lactate Dehydrogenase and Reduced Diphosphopyridine Nucleotide*

    PubMed Central

    Sarma, Ramaswamy H.; Kaplan, Nathan O.

    1970-01-01

    220 MHz proton nuclear magnetic resonance investigations of reduced pyridine coenzymes and coenzyme fragments, both in the presence and absence of M4 lactate dehydrogenase, show the following: (1) That the energy barrier between a folded and open conformation of the reduced pyridine coenzyme (in aqueous solutions) is insignificant because an unfavorable enthalpy change of 5 kcal is compensated for by a favorable entropy change of 19 entropy units. (2) The coenzyme, however, appears to maintain its intramolecularly folded conformation on contact with the enzyme. The binding of the coenzyme results in the immobilization of the adenine and pyridine moieties and there is no longer any gain in the conformational entropy as a result of unfolding as in aqueous solutions. (3) The purine moiety of the coenzyme facilitates the binding of the pyridine ring and indicates how high frequency nuclear magnetic resonance can be utilized to study binding of small molecules to enzymes. PMID:4395025

  13. The Conformation of NAD+ Bound to Lactate Dehydrogenase Determined by Nuclear Magnetic Resonance with Suppression of Spin Diffusion

    NASA Astrophysics Data System (ADS)

    Vincent, Sebastien J. F.; Zwahlen, Catherine; Post, Carol Beth; Burgner, John W.; Bodenhausen, Geoffrey

    1997-04-01

    We have reinvestigated the conformation of NAD+ bound to dogfish lactate dehydrogenase (LDH) by using an NMR experiment that allows one to exploit nuclear Overhauser effects to determine internuclear distances between pairs of protons, without perturbation of spin-diffusion effects from other protons belonging either to the cofactor or to the binding pocket of the enzyme. The analysis indicates that the structure of bound NAD+ is in accord with the conformation determined in the solid state by x-ray diffraction for the adenosine moiety, but deviates significantly from that of the nicotinamide. The NMR data indicate conformational averaging about the glycosidic bond of the nicotinamide nucleotide. In view of the strict stereospecificity of catalysis by LDH and the conformational averaging of bound NAD+ that we infer from solution-state NMR, we suggest that LDH binds the cofactor in both syn and anti conformations, but that binding interactions in the syn conformation are not catalytically productive.

  14. Isolation and characterization of two cDNA clones of anaerobically induced lactate dehydrogenase from barley roots

    SciTech Connect

    Hondred, D.; Hanson, A.D. )

    1990-05-01

    In barley roots during hypoxia, five lactate dehydrogenase (LDH) isozymes accumulate with a concomitant increase in enzyme activity ({approximately}20-fold). These isozymes are thought to be tetramers resulting from the random association of the products of two Ldh loci. To investigate this system, cDNA clones of LDH have been isolated from a {lambda}gt11 library using antiserum raised against barley LDH purified {approximately}3,000-fold and using nucleic acid probes synthesized by the polymerase chain reaction. Two cDNA clones were obtained (1,305 and 1,166 bp). The deduced amino acid sequences of the two barley LDHs are 96% identical to each other, and 50% and 40% identical to vertebrate and bacterial LDHs, respectively. Northern blots identified a single mRNA band ({approximately}1.5 kb) whose level rose 8-fold during hypoxia.

  15. Cationic Surfactant-Based Colorimetric Detection of Plasmodium Lactate Dehydrogenase, a Biomarker for Malaria, Using the Specific DNA Aptamer

    PubMed Central

    Lee, Seonghwan; Manjunatha, D H; Jeon, Weejeong; Ban, Changill

    2014-01-01

    A simple, sensitive, and selective colorimetric biosensor for the detection of the malarial biomarkers Plasmodium vivax lactate dehydrogenase (PvLDH) and Plasmodium falciparum LDH (PfLDH) was demonstrated using the pL1 aptamer as the recognition element and gold nanoparticles (AuNPs) as probes. The proposed method is based on the aggregation of AuNPs using hexadecyltrimethylammonium bromide (CTAB). The AuNPs exhibited a sensitive color change from red to blue, which could be seen directly with the naked eye and was monitored using UV-visible absorption spectroscopy and transmission electron microscopy (TEM). The reaction conditions were optimized to obtain the maximum color intensity. PvLDH and PfLDH were discernible with a detection limit of 1.25 pM and 2.94 pM, respectively. The applicability of the proposed biosensor was also examined in commercially available human serum. PMID:24992632

  16. Combined inactivation of the Clostridium cellulolyticum lactate and malate dehydrogenase genes substantially increases ethanol yield from cellulose and switchgrass fermentations

    SciTech Connect

    Li, Yongchao; Tschaplinski, Timothy J; Engle, Nancy L; Hamilton, Choo Yieng; Rodriguez, Jr., Miguel; Liao, James C; Schadt, Christopher Warren; Guss, Adam M; Yang, Yunfeng; Graham, David E

    2012-01-01

    Background: The model bacterium Clostridium cellulolyticum efficiently hydrolyzes crystalline cellulose and hemicellulose, using cellulosomes to degrade lignocellulosic biomass. Although it imports and ferments both pentose and hexose sugars to produce a mixture of ethanol, acetate, lactate, H2 and CO2, the proportion of ethanol is low, which impedes its use in consolidated bioprocessing for biofuels. Therefore genetic engineering will likely be required to improve the ethanol yield. Random mutagenesis, plasmid transformation, and heterologous expression systems have previously been developed for C. cellulolyticum, but targeted mutagenesis has not been reported for this organism. Results: The first targeted gene inactivation system was developed for C. cellulolyticum, based on a mobile group II intron originating from the Lactococcus lactis L1.LtrB intron. This markerless mutagenesis system was used to disrupt both the paralogous L-lactate dehydrogenase (Ccel_2485; ldh) and L-malate dehydrogenase (Ccel_0137; mdh) genes, distinguishing the overlapping substrate specificities of these enzymes. Both mutations were then combined in a single strain. This double mutant produced 8.5-times more ethanol than wild-type cells growing on crystalline cellulose. Ethanol constituted 93% of the major fermentation products (by molarity), corresponding to a molar ratio of ethanol to organic acids of 15, versus 0.18 in wild-type cells. During growth on acid-pretreated switchgrass, the double mutant also produced four-times as much ethanol as wild-type cells. Detailed metabolomic analyses identified increased flux through the oxidative branch of the mutant s TCA pathway. Conclusions: The efficient intron-based gene inactivation system produced the first gene-targeted mutations in C. cellulolyticum. As a key component of the genetic toolbox for this bacterium, markerless targeted mutagenesis enables functional genomic research in C. cellulolyticum and rapid genetic engineering to significantly alter the mixture of fermentation products. The initial application of this system successfully engineered a strain with high ethanol productivity from complex biomass substrates.

  17. Production of l-lactic acid by the yeast Candida sonorensis expressing heterologous bacterial and fungal lactate dehydrogenases

    PubMed Central

    2013-01-01

    Background Polylactic acid is a renewable raw material that is increasingly used in the manufacture of bioplastics, which offers a more sustainable alternative to materials derived from fossil resources. Both lactic acid bacteria and genetically engineered yeast have been implemented in commercial scale in biotechnological production of lactic acid. In the present work, genes encoding l-lactate dehydrogenase (LDH) of Lactobacillus helveticus, Bacillus megaterium and Rhizopus oryzae were expressed in a new host organism, the non-conventional yeast Candida sonorensis, with or without the competing ethanol fermentation pathway. Results Each LDH strain produced substantial amounts of lactate, but the properties of the heterologous LDH affected the distribution of carbon between lactate and by-products significantly, which was reflected in extra-and intracellular metabolite concentrations. Under neutralizing conditions C. sonorensis expressing L. helveticus LDH accumulated lactate up to 92 g/l at a yield of 0.94 g/g glucose, free of ethanol, in minimal medium containing 5 g/l dry cell weight. In rich medium with a final pH of 3.8, 49 g/l lactate was produced. The fermentation pathway was modified in some of the strains studied by deleting either one or both of the pyruvate decarboxylase encoding genes, PDC1 and PDC2. The deletion of both PDC genes together abolished ethanol production and did not result in significantly reduced growth characteristic to Saccharomyces cerevisiae deleted of PDC1 and PDC5. Conclusions We developed an organism without previous record of genetic engineering to produce L-lactic acid to a high concentration, introducing a novel host for the production of an industrially important metabolite, and opening the way for exploiting C. sonorensis in additional biotechnological applications. Comparison of metabolite production, growth, and enzyme activities in a representative set of transformed strains expressing different LDH genes in the presence and absence of a functional ethanol pathway, at neutral and low pH, generated a comprehensive picture of lactic acid production in this yeast. The findings are applicable in generation other lactic acid producing yeast, thus providing a significant contribution to the field of biotechnical production of lactic acid. PMID:23706009

  18. Age-related responses of right ventricle in swim-trained rats: changes in lactate and pyruvate contents and lactate dehydrogenase activity.

    PubMed

    Anitha, V; Asha Devi, S

    1996-09-18

    Age related changes in carbohydrate substrates such as, glucose, glycogen, pyruvic acid and lactic acid and the activity of lactate dehydrogenase (LDH) and LDH isoenzyme profile were evaluated in the right ventricle (RV) of swim-trained rats of 6- (adult), 12- (middle-aged) and 18- (old) months-of-age. Moderate hypertrophy was seen in the heart and RV in response to training in all age groups with the 12 months exhibiting a significant increase. While resting levels of pyruvate and glucose in the RV showed small elevations in adult and middle-aged rats, lactic acid showed reductions in all ages. Glycogen supercompensation was seen in the RV of trained animals. These age-related alterations in RV were associated with decreases in blood lactic acid and glucose in the trained rats belonging to all ages. Total protein of the RV decreased with age and exercise increased the content. Total LDH and M4-LDH activities decreased with age. However, training increased their activities in all ages. These changes in the RV suggests that swimming activity produces adaptations (e.g. increased LDH and M4) in all age groups. Considering the degree of adaptations, it can be suggested that adult and middle-aged are suitable for initiating swim-training programs, but not in old age. PMID:8869911

  19. Protein Conformational Landscapes and Catalysis. Influence of Active Site Conformations in the Reaction Catalyzed by L-Lactate Dehydrogenase

    PubMed Central

    Świderek, Katarzyna; Tuñón, Iñaki; Martí, Sergio; Moliner, Vicent

    2015-01-01

    In the last decade L-Lactate Dehydrogenase (LDH) has become an extremely useful marker in both clinical diagnosis and in monitoring the course of many human diseases. It has been assumed from the 80s that the full catalytic process of LDH starts with the binding of the cofactor and the substrate followed by the enclosure of the active site by a mobile loop of the protein before the reaction to take place. In this paper we show that the chemical step of the LDH catalyzed reaction can proceed within the open loop conformation, and the different reactivity of the different protein conformations would be in agreement with the broad range of rate constants measured in single molecule spectrometry studies. Starting from a recently solved X-ray diffraction structure that presented an open loop conformation in two of the four chains of the tetramer, QM/MM free energy surfaces have been obtained at different levels of theory. Depending on the level of theory used to describe the electronic structure, the free energy barrier for the transformation of pyruvate into lactate with the open conformation of the protein varies between 12.9 and 16.3 kcal/mol, after quantizing the vibrations and adding the contributions of recrossing and tunneling effects. These values are very close to the experimentally deduced one (14.2 kcal·mol−1) and ~2 kcal·mol−1 smaller than the ones obtained with the closed loop conformer. Calculation of primary KIEs and IR spectra in both protein conformations are also consistent with our hypothesis and in agreement with experimental data. Our calculations suggest that the closure of the active site is mainly required for the inverse process; the oxidation of lactate to pyruvate. According to this hypothesis H4 type LDH enzyme molecules, where it has been propose that lactate is transformed into pyruvate, should have a better ability to close the mobile loop than the M4 type LDH molecules. PMID:25705562

  20. Lactation

    PubMed Central

    1989-01-01

    Lactation is the most energy-efficient way to provide for the dietary needs of young mammals, their mother's milk being actively protective, immunomodulatory, and ideal for their needs. Intrauterine mammary gland development in the human female is already apparent by the end of the sixth week of gestation. During puberty and adolescence secretions of the anterior pituitary stimulate the maturation of the graafian follicles in the ovaries and stimulate the secretion of follicular estrogens, which stimulate development of the mammary ducts. Pregnancy has the most dramatic effect on the breast, but development of the glandular breast tissue and deposition of fat and connective tissue continue under the influence of cyclic sex-hormone stimulation. Many changes occur in the nipple and breast during pregnancy and at delivery as a prelude to lactation. Preparation of the breasts is so effective that lactation could commence even if pregnancy were discontinued at 16 weeks. Following birth, placental inhibition of milk synthesis is removed, and a woman's progesterone blood levels decline rapidly. The breasts fill with milk, which is a high-density, low-volume feed called colostrum until about 30 hours after birth. Because it is not the level of maternal hormones, but the efficiency of infant suckling and/or milk removal that governs the volume of milk produced in each breast, mothers who permit their infants to feed ad libitum commonly observe that they have large volumes of milk 24-48 hours after birth. The two maternal reflexes involved in lactation are the milk-production and milk-ejection reflex. A number of complementary reflexes are involved when the infant feeds: the rooting reflex (which programmes the infant to search for the nipple), the sucking reflex (rhythmic jaw action creating negative pressure and a peristaltic action of the tongue), and the swallowing reflex. The infant's instinctive actions need to be consolidated into learned behaviour in the postpartum period when the use of artificial teats and dummies (pacifiers) may condition the infant to different oral actions that are inappropriate for breast-feeding. Comparisons of breast milk and cow's milk fail to describe the many important differences between them, e.g., the structural and qualitative differences in proteins and fats, and the bioavailability of minerals. The protection against infection and allergies conferred on the infant, which is impossible to attain through any other feeding regimen, is one of breast milk's most outstanding qualities. The maximum birth-spacing effect of lactation is achieved when an infant is fully, or nearly fully, breast-fed and the mother consequently remains amenorrhoeic. PMID:20604468

  1. Escherichia coli derivatives lacking both alcohol dehydrogenase and phosphotransacetylase grow anaerobically by lactate fermentation

    SciTech Connect

    Gupta, S.; Clark, D.P. )

    1989-07-01

    Escherichia coli mutants lacking alcohol dehydrogenase (adh mutants) cannot synthesize the fermentation product ethanol and are unable to grow anaerobically on glucose and other hexoses. Similarly, phosphotransacetylase-negative mutants (pta mutants) neither excrete acetate nor grow anaerobically. However, when a strain carrying an adh deletion was selected for anaerobic growth on glucose, spontaneous pta mutants were isolated. Strains carrying both adh and pta mutations were observed by in vivo nuclear magnetic resonance and shown to produce lactic acid as the major fermentation product. Various combinations of adh pta double mutants regained the ability to grow anaerobically on hexoses, by what amounts to a homolactic fermentation. Unlike wild-type strains, such adh pta double mutants were unable to grow anaerobically on sorbitol or on glucuronic acid. The growth properties of strains carrying various mutations affecting the enzymes of fermentation are discussed terms of redox balance.

  2. Escherichia coli derivatives lacking both alcohol dehydrogenase and phosphotransacetylase grow anaerobically by lactate fermentation.

    PubMed Central

    Gupta, S; Clark, D P

    1989-01-01

    Escherichia coli mutants lacking alcohol dehydrogenase (adh mutants) cannot synthesize the fermentation product ethanol and are unable to grow anaerobically on glucose and other hexoses. Similarly, phosphotransacetylase-negative mutants (pta mutants) neither excrete acetate nor grow anaerobically. However, when a strain carrying an adh deletion was selected for anaerobic growth on glucose, spontaneous pta mutants were isolated. Strains carrying both adh and pta mutations were observed by in vivo nuclear magnetic resonance and shown to produce lactic acid as the major fermentation product. Various combinations of adh pta double mutants regained the ability to grow anaerobically on hexoses, by what amounts to a homolactic fermentation. Unlike wild-type strains, such adh pta double mutants were unable to grow anaerobically on sorbitol or on glucuronic acid. The growth properties of strains carrying various mutations affecting the enzymes of fermentation are discussed in terms of redox balance. PMID:2661531

  3. Cloning, expression, purification, crystallization and X-ray crystallographic analysis of D-lactate dehydrogenase from Lactobacillus jensenii.

    PubMed

    Kim, Sangwoo; Kim, Yong Hwan; Kim, Kyung-Jin

    2014-08-01

    The thermostable D-lactate dehydrogenase from Lactobacillus jensenii (LjD-LDH) is a key enzyme for the production of the D-form of lactic acid from pyruvate concomitant with the oxidation of NADH to NAD(+). The polymers of lactic acid are used as biodegradable bioplastics. The LjD-LDH protein was crystallized using the hanging-drop vapour-diffusion method in the presence of 28%(w/v) polyethylene glycol 400, 100 mM Tris-HCl pH 9, 200 mM magnesium sulfate at 295 K. X-ray diffraction data were collected to a maximum resolution of 2.1 Å. The crystal belonged to space group P3121, with unit-cell parameters a = b = 90.5, c = 157.8 Å. With two molecules per asymmetric unit, the crystal volume per unit protein weight (VM) is 2.58 Å(3) Da(-1), which corresponds to a solvent content of approximately 52.3%. The structure was solved by single-wavelength anomalous dispersion using a selenomethionine derivative. PMID:25084378

  4. The value of lactate dehydrogenase serum levels as a prognostic and predictive factor for advanced pancreatic cancer patients receiving sorafenib

    PubMed Central

    Faloppi, Luca; Bianconi, Maristella; Giampieri, Riccardo; Sobrero, Alberto; Labianca, Roberto; Ferrari, Daris; Barni, Sandro; Aitini, Enrico; Zaniboni, Alberto; Boni, Corrado; Caprioni, Francesco; Mosconi, Stefania; Fanello, Silvia; Berardi, Rossana; Bittoni, Alessandro; Andrikou, Kalliopi; Cinquini, Michela; Torri, Valter; Scartozzi, Mario; Cascinu, Stefano

    2015-01-01

    Although lactate dehydrogenase (LDH) serum levels, indirect markers of angiogenesis, are associated with a worse outcome in several tumours, their prognostic value is not defined in pancreatic cancer. Moreover, high levels are associated even with a lack of efficacy of tyrosine kinase inhibitors, contributing to explain negative results in clinical trials. We assessed the role of LDH in advanced pancreatic cancer receiving sorafenib. Seventy-one of 114 patients included in the randomised phase II trial MAPS (chemotherapy plus or not sorafenib) and with available serum LDH levels, were included in this analysis. Patients were categorized according to serum LDH levels (LDH ≤vs.> upper normal rate). A significant difference was found in progression free survival (PFS) and in overall survival (OS) between patients with LDH values under or above the cut-off (PFS: 5.2 vs. 2.7 months, p = 0.0287; OS: 10.7 vs. 5.9 months, p = 0.0021). After stratification according to LDH serum levels and sorafenib treatment, patients with low LDH serum levels treated with sorafenib showed an advantage in PFS (p = 0.05) and OS (p = 0.0012). LDH appears to be a reliable parameter to assess the prognosis of advanced pancreatic cancer patients, and it may be a predictive parameter to select patients candidate to receive sorafenib. PMID:26397228

  5. Measurements of C-reactive protein in serum and lactate dehydrogenase in serum and synovial fluid of patients with osteoarthritis.

    PubMed

    Hurter, K; Spreng, D; Rytz, U; Schawalder, P; Ott-Knüsel, F; Schmökel, H

    2005-03-01

    Diagnosis of osteoarthritis (OA) is based upon the clinical orthopaedic examination and the radiographic assessment, both of which can be non-specific and insensitive in early joint disease. The aim of our study was to investigate if there is an increase in serum levels of C-reactive protein (CRP) in degenerative joint disease (DJD) and if CRP could be used to help diagnose OA. We also wished to investigate whether it was possible to distinguish a joint with clinically and radiographically confirmed OA from a healthy joint by comparing lactate dehydrogenase (LDH) levels within the synovial fluid and the serum. We have shown a difference in synovial LDH levels between diseased and healthy joints (P<0.0001). There was also a significant difference between LDH in arthritic synovial fluid and serum, with no correlation between the values. Despite the fact that the values of our clinical patients tended to be higher than the values of our control group (P=0.05) all measured values were within the normal limits of previous publications. From these data, we conclude that single measurements of serum CRP do not permit detection of OA in clinical patients and that serum LDH is not a reliable marker for osteoarthritis. LDH levels in the synovial fluid could be of diagnostic value for identifying osteoarthritis. PMID:15727922

  6. Prognostic implications of dynamic serum lactate dehydrogenase assessments in nasopharyngeal carcinoma patients treated with intensity-modulated radiotherapy.

    PubMed

    Zhou, Guan-Qun; Ren, Xian-Yue; Mao, Yan-Ping; Chen, Lei; Sun, Ying; Liu, Li-Zhi; Li, Li; Lin, Ai-Hua; Mai, Hai-Qiang; Ma, Jun

    2016-01-01

    The prognostic value of dynamic serum lactate dehydrogenase (LDH) levels in patients with nasopharyngeal carcinoma (NPC) treated with intensity-modulated radiotherapy (IMRT) hasn't been explored. We retrospectively analyzed 1,428 cases of NPC treated with IMRT with or without chemotherapy. Elevated pre- and/or post-treatment LDH levels were found to be associated with unfavorable overall survival (OS), disease-free survival (DFS) and distant metastasis-free survival (DMFS), but not with local relapse-free survival (LRFS). The dynamic variations in LDH levels were prognostic factors for OS, DFS and DMFS, but not for LRFS. Multivariate analysis revealed that the N category, T category, post-treatment serum LDH level and age were independent prognostic factors for OS. Our results demonstrated that dynamic variations in LDH levels were associated with risk of distant failure and death, which may shed light on the dynamics of the disease and the response to therapy. We consider that LDH measurements will be of great clinical importance in the management of NPC, especially, when considering "decision points" in treatment algorithms. Therefore, we strongly recommend that LDH levels should be determined before and after treatment in NPC patients and the results integrated into decisions regarding treatment strategies. PMID:26928265

  7. Lactate dehydrogenase like crystallin: a potentially protective shield for indian spiny-tailed lizard (Uromastyx hardwickii) lens against environmental stress?

    PubMed

    Atta, Ambreen; Ilyas, Amber; Hashim, Zehra; Ahmed, Aftab; Zarina, Shamshad

    2014-04-01

    Taxon specific lens crystallins in vertebrates are either similar or identical with various metabolic enzymes. These bifunctional crystallins serve as structural protein in lens along with their catalytic role. In the present study, we have partially purified and characterized lens crystallin from Indian spiny-tailed lizard (Uromastyx hardwickii). We have found lactate dehydrogenase (LDH) activity in lens indicating presence of an enzyme crystallin with dual functions. Taxon specific lens crystallins are product of gene sharing or gene duplication phenomenon where a pre-existing enzyme is recruited as lens crystallin in addition to structural role. In lens, same gene adopts refractive role in lens without modification or loss of pre-existing function during gene sharing phenomenon. Apart from conventional role of structural protein, LDH activity containing crystallin in U. hardwickii lens is likely to have adaptive characteristics to offer protection against toxic effects of oxidative stress and ultraviolet light, hence justifying its recruitment. Taxon specific crystallins may serve as good models to understand structure-function relationship of these proteins. PMID:24500074

  8. Effects and Mechanism of Atmospheric-Pressure Dielectric Barrier Discharge Cold Plasma on Lactate Dehydrogenase (LDH) Enzyme

    NASA Astrophysics Data System (ADS)

    Zhang, Hao; Xu, Zimu; Shen, Jie; Li, Xu; Ding, Lili; Ma, Jie; Lan, Yan; Xia, Weidong; Cheng, Cheng; Sun, Qiang; Zhang, Zelong; Chu, Paul K.

    2015-05-01

    Proteins are carriers of biological functions and the effects of atmospheric-pressure non-thermal plasmas on proteins are important to applications such as sterilization and plasma-induced apoptosis of cancer cells. Herein, we report our detailed investigation of the effects of helium-oxygen non-thermal dielectric barrier discharge (DBD) plasmas on the inactivation of lactate dehydrogenase (LDH) enzyme solutions. Circular dichroism (CD) and dynamic light scattering (DLS) indicate that the loss of activity stems from plasma-induced modification of the secondary molecular structure as well as polymerization of the peptide chains. Raising the treatment intensity leads to a reduced alpha-helix content, increase in the percentage of the beta-sheet regions and random sequence, as well as gradually decreasing LDH activity. However, the structure of the LDH plasma-treated for 300 seconds exhibits a recovery trend after storage for 24 h and its activity also increases slightly. By comparing direct and indirect plasma treatments, plasma-induced LDH inactivation can be attributed to reactive species (RS) in the plasma, especially ones with a long lifetime including hydrogen peroxide, ozone, and nitrate ion which play the major role in the alteration of the macromolecular structure and molecular diameter in lieu of heat, UV radiation, and charged particles.

  9. Effects and Mechanism of Atmospheric-Pressure Dielectric Barrier Discharge Cold Plasma on Lactate Dehydrogenase (LDH) Enzyme.

    PubMed

    Zhang, Hao; Xu, Zimu; Shen, Jie; Li, Xu; Ding, Lili; Ma, Jie; Lan, Yan; Xia, Weidong; Cheng, Cheng; Sun, Qiang; Zhang, Zelong; Chu, Paul K

    2015-01-01

    Proteins are carriers of biological functions and the effects of atmospheric-pressure non-thermal plasmas on proteins are important to applications such as sterilization and plasma-induced apoptosis of cancer cells. Herein, we report our detailed investigation of the effects of helium-oxygen non-thermal dielectric barrier discharge (DBD) plasmas on the inactivation of lactate dehydrogenase (LDH) enzyme solutions. Circular dichroism (CD) and dynamic light scattering (DLS) indicate that the loss of activity stems from plasma-induced modification of the secondary molecular structure as well as polymerization of the peptide chains. Raising the treatment intensity leads to a reduced alpha-helix content, increase in the percentage of the beta-sheet regions and random sequence, as well as gradually decreasing LDH activity. However, the structure of the LDH plasma-treated for 300 seconds exhibits a recovery trend after storage for 24 h and its activity also increases slightly. By comparing direct and indirect plasma treatments, plasma-induced LDH inactivation can be attributed to reactive species (RS) in the plasma, especially ones with a long lifetime including hydrogen peroxide, ozone, and nitrate ion which play the major role in the alteration of the macromolecular structure and molecular diameter in lieu of heat, UV radiation, and charged particles. PMID:25992482

  10. Cryptosporidium Lactate Dehydrogenase Is Associated with the Parasitophorous Vacuole Membrane and Is a Potential Target for Developing Therapeutics

    PubMed Central

    Zhu, Guan

    2015-01-01

    Abstract The apicomplexan, Cryptosporidium parvum, possesses a bacterial-type lactate dehydrogenase (CpLDH). This is considered to be an essential enzyme, as this parasite lacks the Krebs cycle and cytochrome-based respiration, and mainly–if not solely, relies on glycolysis to produce ATP. Here, we provide evidence that in extracellular parasites (e.g., sporozoites and merozoites), CpLDH is localized in the cytosol. However, it becomes associated with the parasitophorous vacuole membrane (PVM) during the intracellular developmental stages, suggesting involvement of the PVM in parasite energy metabolism. We characterized the biochemical features of CpLDH and observed that, at lower micromolar levels, the LDH inhibitors gossypol and FX11 could inhibit both CpLDH activity (Ki = 14.8 μM and 55.6 μM, respectively), as well as parasite growth in vitro (IC50 = 11.8 μM and 39.5 μM, respectively). These observations not only reveal a new function for the poorly understood PVM structure in hosting the intracellular development of C. parvum, but also suggest LDH as a potential target for developing therapeutics against this opportunistic pathogen, for which fully effective treatments are not yet available. PMID:26562790

  11. Effects and Mechanism of Atmospheric-Pressure Dielectric Barrier Discharge Cold Plasma on Lactate Dehydrogenase (LDH) Enzyme

    PubMed Central

    Zhang, Hao; Xu, Zimu; Shen, Jie; Li, Xu; Ding, Lili; Ma, Jie; Lan, Yan; Xia, Weidong; Cheng, Cheng; Sun, Qiang; Zhang, Zelong; Chu, Paul K.

    2015-01-01

    Proteins are carriers of biological functions and the effects of atmospheric-pressure non-thermal plasmas on proteins are important to applications such as sterilization and plasma-induced apoptosis of cancer cells. Herein, we report our detailed investigation of the effects of helium-oxygen non-thermal dielectric barrier discharge (DBD) plasmas on the inactivation of lactate dehydrogenase (LDH) enzyme solutions. Circular dichroism (CD) and dynamic light scattering (DLS) indicate that the loss of activity stems from plasma-induced modification of the secondary molecular structure as well as polymerization of the peptide chains. Raising the treatment intensity leads to a reduced alpha-helix content, increase in the percentage of the beta-sheet regions and random sequence, as well as gradually decreasing LDH activity. However, the structure of the LDH plasma-treated for 300 seconds exhibits a recovery trend after storage for 24 h and its activity also increases slightly. By comparing direct and indirect plasma treatments, plasma-induced LDH inactivation can be attributed to reactive species (RS) in the plasma, especially ones with a long lifetime including hydrogen peroxide, ozone, and nitrate ion which play the major role in the alteration of the macromolecular structure and molecular diameter in lieu of heat, UV radiation, and charged particles. PMID:25992482

  12. Adjustments of serum lactate dehydrogenase isoenzymes and their significance in monitoring the treatment in patients with tubercular pyothorax.

    PubMed

    Ahmad, Riaz; Alam, Mumtaz; Siddiqui, M Faisal; Hasnain, Absar-Ul

    2008-04-01

    The adjustments and diagnostic significance of polyacrylamide gel electrophoretic (PAGE) profiles of lactate dehydrogenase isoenzymes (LDH: 1.1.1.27) was evaluated in the sera and pleural fluid of patients with tubercular pyothorax. Sera and pleural fluid samples were randomly collected from 72 and 18 patients respectively at two different timings; first, when patients were admitted to the Hospital and second, after an intensive phase of treatment. Sera of 20 healthy individuals served as control. Our results demonstrate significant differences in sera LDH (sLDH) and pleural fluid LDH (pfLDH) isoenzymes. In patients the order of LDH isoenzyme in sera and pleural fluid followed: LDH-5>-4>-2>-3>-1 and LDH-5>-4>-3>-2>-1 respectively. The ranking of activity levels in control was LDH-2>-1>-3>-5>-4. In the second phase of sampling from 31 patients, values of sLDH isoenzymes showed recovery and resembled profiles of controls. Therefore, the sLDH zymograms of patients can be used as the prognostic marker, since they tend to reach the normal level during recovery signifying the effect of chemotherapy in hospitalized patients. Moreover, according to the present findings on LDH-PAGE profiles, the levels of LDH-5 and-4 rise in pyothorax patients significantly (P<0.05). This elevation along with the rise in total LDH activity may, therefore, be used in the diagnosis and monitoring of tubercular pyothorax. PMID:23105748

  13. Lactate dehydrogenase as a marker of nasopharyngeal inflammatory injury during viral upper respiratory infection: implications for acute otitis media

    PubMed Central

    Ede, Linda C.; OBrien, James; Chonmaitree, Tasnee; Han, Yimei; Patel, Janak A.

    2013-01-01

    Background Acute otitis media (AOM) is a frequent complication of viral upper respiratory tract infection (URI). We hypothesized that severity of nasopharyngeal cellular injury during URI, as measured by lactate dehydrogenase (LDH) concentrations in nasopharyngeal secretions (NPS), is related to AOM complication. Methods LDH concentrations were determined in NPS samples (n=594) which were collected at the initial visit for URI from 183 children who were followed for development of AOM. A subset of NPS samples (n= 134) were analyzed for interleukin (IL)-1?, IL-6, and tumor necrosis factor (TNF) ? concentrations. Results AOM complication was independently predicted by LDH concentrations (median mU/ml with AOM = 2438 vs. without AOM = 1573, estimate=0.276; P=0.02). LDH effect on AOM development was highest during the first 4 days of URI. LDH concentrations were higher in URIs due to adenoviruses, bocaviruses, and rhinoviruses when compared to virus-negative samples (P <0.05). There was a positive correlation between concentrations of LDH and all cytokines (P< 0.001). Conclusion LDH concentrations in NPS are positively associated with AOM risk, suggesting that the severity of nasopharyngeal inflammatory injury during URI contributes to the development of AOM, and that reduction of inflammatory injury may reduce the risk for AOM. PMID:23202721

  14. Elevated lactate dehydrogenase activity and increased cardiovascular mortality in the arsenic-endemic areas of southwestern Taiwan.

    PubMed

    Liao, Ya-Tang; Chen, Chien-Jen; Li, Wan-Fen; Hsu, Ling-I; Tsai, Li-Yu; Huang, Yeou-Lih; Sun, Chien-Wen; Chen, Wei J; Wang, Shu-Li

    2012-08-01

    Arsenic ingestion has been linked to increasing global prevalence of and mortality from cardiovascular disease (CVD); arsenic can be removed from drinking water to reduce related health effects. Lactate dehydrogenase (LDH) is used for the evaluation of acute arsenic toxicity in vivo and in vitro, but it is not validated for the evaluation of long-term, chronic arsenic exposure. The present study examined the long-term effect of chronic arsenic exposure on CVD and serum LDH levels, after consideration of arsenic metabolism capacity. A total of 380 subjects from an arseniasis-endemic area and 303 from a non-endemic area of southwestern Taiwan were recruited in 2002. Various urinary arsenic species were analyzed using high-performance liquid chromatography (HPLC) and hydride generation systems. Fasting serum was used for quantitative determination of the total LDH activity. A significant dose-response relationship was observed between arsenic exposure and LDH elevation, independent of urinary arsenic profiles (P<0.001). Furthermore, abnormal LDH elevation was associated with CVD mortality after adjustment for Framingham risk scores for 10-year CVD and arsenic exposure (hazard ratio, 3.98; 95% confidence interval, 1.07-14.81). LDH was elevated in subjects with arsenic exposure in a dose-dependent manner. LDH is a marker of arsenic toxicity associated with CVD mortality. Results of this study have important implications for use in ascertaining long-term arsenic exposure risk of CVD. PMID:22569360

  15. Prognostic implications of dynamic serum lactate dehydrogenase assessments in nasopharyngeal carcinoma patients treated with intensity-modulated radiotherapy

    PubMed Central

    Zhou, Guan-Qun; Ren, Xian-Yue; Mao, Yan-Ping; Chen, Lei; Sun, Ying; Liu, Li-Zhi; Li, Li; Lin, Ai-Hua; Mai, Hai-Qiang; Ma, Jun

    2016-01-01

    The prognostic value of dynamic serum lactate dehydrogenase (LDH) levels in patients with nasopharyngeal carcinoma (NPC) treated with intensity-modulated radiotherapy (IMRT) hasn’t been explored. We retrospectively analyzed 1,428 cases of NPC treated with IMRT with or without chemotherapy. Elevated pre- and/or post-treatment LDH levels were found to be associated with unfavorable overall survival (OS), disease-free survival (DFS) and distant metastasis-free survival (DMFS), but not with local relapse-free survival (LRFS). The dynamic variations in LDH levels were prognostic factors for OS, DFS and DMFS, but not for LRFS. Multivariate analysis revealed that the N category, T category, post-treatment serum LDH level and age were independent prognostic factors for OS. Our results demonstrated that dynamic variations in LDH levels were associated with risk of distant failure and death, which may shed light on the dynamics of the disease and the response to therapy. We consider that LDH measurements will be of great clinical importance in the management of NPC, especially, when considering “decision points” in treatment algorithms. Therefore, we strongly recommend that LDH levels should be determined before and after treatment in NPC patients and the results integrated into decisions regarding treatment strategies. PMID:26928265

  16. Molecular basis of evolutionary adaptation at the lactate dehydrogenase-B locus in the fish Fundulus heteroclitus.

    PubMed Central

    Crawford, D L; Powers, D A

    1989-01-01

    At the extremes of its natural distribution, populations of the common killifish Fundulus heteroclitus experience a difference of more than 15 degrees C in mean annual temperature. These populations are virtually fixed for two different codominant alleles at the heart-type lactate dehydrogenase locus (Ldh-B) which code for allozymes with different and adaptive kinetic responses to temperature. Two populations near the extremes of the species range (i.e., Maine and Georgia) were further studied for thermal adaptation at this locus. In the absence of any kinetic differences one would predict that to maintain a constant reaction velocity, 2 to 3 times as much enzyme would be required for each 10 degrees C decrease in environmental temperature. Consistent with this adaptive strategy and in addition to the adaptive kinetic characteristics, the LDH-B4 enzyme (EC 1.1.1.27) concentration and its mRNA concentration were approximately twice as great in the northern population as in the southern population. Acclimation experiments allow us to conclude that these differences are due to a combination of fixed genetic traits (evolutionary adaptation) and plastic responses to temperature (physiological acclimation). Furthermore, our calculations show that the LDH-B4 reaction velocities are essentially equivalent for these two populations, even though they live in significantly different thermal environments. PMID:2594773

  17. Purification of a recombinant histidine-tagged lactate dehydrogenase from the malaria parasite, Plasmodium vivax, and characterization of its properties.

    PubMed

    Sundaram, Balamurugan; Varadarajan, Nandan Mysore; Subramani, Pradeep Annamalai; Ghosh, Susanta Kumar; Nagaraj, Viswanathan Arun

    2014-12-01

    Lactate dehydrogenase (LDH) of the malaria parasite, Plasmodium vivax (Pv), serves as a drug target and immunodiagnostic marker. The LDH cDNA generated from total RNA of a clinical isolate of the parasite was cloned into pRSETA plasmid. Recombinant his-tagged PvLDH was over-expressed in E. coli Rosetta2DE3pLysS and purified using Ni(2+)-NTA resin giving a yield of 25-30mg/litre bacterial culture. The recombinant protein was enzymatically active and its catalytic efficiency for pyruvate was 5.4נ10(8)min(-1)M(-1), 14.5 fold higher than a low yield preparation reported earlier to obtain PvLDH crystal structure. The enzyme activity was inhibited by gossypol and sodium oxamate. The recombinant PvLDH was reactive in lateral flow immunochromatographic assays detecting pan- and vivax-specific LDH. The soluble recombinant PvLDH purified using heterologous expression system can facilitate the generation of vivax LDH-specific monoclonals and the screening of chemical compound libraries for PvLDH inhibitors. PMID:25048245

  18. Serial lumbar and ventricle cerebrospinal fluid lactate dehydrogenase activities in patients with leptomeningeal metastases from solid and haematological tumours.

    PubMed Central

    Twijnstra, A; van Zanten, A P; Hart, A A; Ongerboer de Visser, B W

    1987-01-01

    Lactate dehydrogenase (LDH) activities were measured in cerebrospinal fluid in 350 patients with various neurological diseases to establish the sensitivity and specificity of the CSF LDH as a marker for the diagnosis of leptomeningeal metastases. Slight elevations of CSF LDH were observed in nonmalignant diseases, while marked elevations were observed in a considerable number of patients with bacterial meningitis. A sensitivity of 79% and a specificity of 83% were calculated. In the 34 patients with leptomeningeal metastases from solid and haematological tumours, the LDH in lumbar and ventricular CSF were measured simultaneously. The lumbar CSF LDH concentration in patients with leptomeningeal metastases was about five times greater than that in the ventricular CSF. No relationship was found between the CSF LDH and histology of the primary tumour. A good correlation was demonstrated between the lumbar CSF LDH and the effected area of the neuraxis. Serial determinations of CSF LDH showed a relationship between level changes and responses to therapy or progression. The findings of this study indicate that measurement of LDH in CSF can be used as an adjunctive diagnostic test for leptomeningeal metastases and in monitoring the efficacy of treatment. PMID:3559613

  19. Cryptosporidium Lactate Dehydrogenase Is Associated with the Parasitophorous Vacuole Membrane and Is a Potential Target for Developing Therapeutics.

    PubMed

    Zhang, Haili; Guo, Fengguang; Zhu, Guan

    2015-11-01

    The apicomplexan, Cryptosporidium parvum, possesses a bacterial-type lactate dehydrogenase (CpLDH). This is considered to be an essential enzyme, as this parasite lacks the Krebs cycle and cytochrome-based respiration, and mainly-if not solely, relies on glycolysis to produce ATP. Here, we provide evidence that in extracellular parasites (e.g., sporozoites and merozoites), CpLDH is localized in the cytosol. However, it becomes associated with the parasitophorous vacuole membrane (PVM) during the intracellular developmental stages, suggesting involvement of the PVM in parasite energy metabolism. We characterized the biochemical features of CpLDH and observed that, at lower micromolar levels, the LDH inhibitors gossypol and FX11 could inhibit both CpLDH activity (Ki = 14.8 μM and 55.6 μM, respectively), as well as parasite growth in vitro (IC50 = 11.8 μM and 39.5 μM, respectively). These observations not only reveal a new function for the poorly understood PVM structure in hosting the intracellular development of C. parvum, but also suggest LDH as a potential target for developing therapeutics against this opportunistic pathogen, for which fully effective treatments are not yet available. PMID:26562790

  20. The Arabidopsis KS-type dehydrin recovers lactate dehydrogenase activity inhibited by copper with the contribution of His residues.

    PubMed

    Hara, Masakazu; Monna, Shuhei; Murata, Takae; Nakano, Taiyo; Amano, Shono; Nachbar, Markus; Wätzig, Hermann

    2016-04-01

    Dehydrin, which is one of the late embryogenesis abundant (LEA) proteins, is involved in the ability of plants to tolerate the lack of water. Although many reports have indicated that dehydrins bind heavy metals, the physiological role of this metal binding has not been well understood. Here, we report that the Arabidopsis KS-type dehydrin (AtHIRD11) recovered the lactate dehydrogenase (LDH) activity denatured by Cu(2+). The LDH activity was partially inhibited by 0.93μM Cu(2+) but totally inactivated by 9.3μM Cu(2+). AtHIRD11 recovered the activity of LDH treated with 9.3μM Cu(2+) in a dose-dependent manner. The recovery activity of AtHIRD11 was significantly higher than those of serum albumin and lysozyme. The conversion of His residues to Ala in AtHIRD11 resulted in the loss of the Cu(2+) binding of the protein as well as the disappearance of the conformational change induced by Cu(2+) that is observed by circular dichroism spectroscopy. The mutant protein showed lower recovery activity than the original AtHIRD11. These results indicate that AtHIRD11 can reactivate LDH inhibited by Cu(2+) via the His residues. This function may prevent physiological damage to plants due to heavy-metal stress. PMID:26940498

  1. Ontogenetic changes in citrate synthase and lactate dehydrogenase activity in the jumping muscle of the American locust (Schistocerca americana).

    PubMed

    Kirkton, Scott D; Nyberg, Elizabeth T; Fox, Kristin M

    2011-10-01

    Intraspecific studies have repeatedly shown that muscle-specific oxidative enzyme activities scale negatively with body mass while muscle-specific glycolytic enzyme activities scale positively. However, most of these studies have not included juveniles. In this study, we examined how citrate synthase (CS, EC 2.3.3.1) and lactate dehydrogenase (LDH; EC 1.1.1.27) activity in the jumping muscle of Schistocerca americana grasshoppers varied with ontogeny across a 40-fold increase in body size. In contrast to the pattern observed when adult conspecifics are compared, we show that jumping muscle CS activity increased more than 2-fold from 2nd instars to adults, while jumping muscle LDH activity increased more than 5-fold. The increased LDH activity in older grasshoppers supports previous data that older grasshoppers have a reduced jumping endurance. The increased CS activity with age may help older grasshoppers efficiently produce aerobic ATP to bend cuticular springs for energy storage before a jump or alternatively recover from anaerobic metabolism after jumping. Metabolic changes in S. americana jumping muscle are similar to other developing taxa and highlight the importance of including juveniles within intraspecific studies. When compared to adults, juvenile locomotion may have increased selection pressure because of both greater energetic demands during growth and higher predation rates. PMID:21807111

  2. Biochemical and in silico Characterization of Recombinant L-Lactate Dehydrogenase of Theileria annulata.

    PubMed

    Nural, Belma; Erdemir, Aysegul; Mutlu, Ozal; Yakarsonmez, Sinem; Danis, Ozkan; Topuzogullari, Murat; Turgut-Balik, Dilek

    2016-04-01

    Theileria annulata is a parasite that causes theileriosis in cattle. Reports about drug resistance made essential to develop new drug. LDH of Theileria schizonts is the vital enzyme for its anaerobic metabolism. TaLDH gene was first cloned into pGEM-T cloning vector with two introns in our previous study. Here we report cloning of TaLDH without introns into pLATE 31 vector in E. coli BL21(DE3). Protein was in an inactive form. Two mutations were fixed to express the active protein. Protein was purified by affinity chromatography and evaluated by SDS-PAGE and size exclusion chromatography. Optimum pH of enzyme was performed in pH 7.5, and enzyme was stabilized at 20-40 °C. Enzyme kinetics of recombinant TaLDH were found to be in the direction of pyruvate to lactate K m 0.1324 and K i 4.295 mM, k cat , 44.55/s and k cat /K m , 3.3693 × 10(5)/M/s. 3D structure of TaLDH was predicted, and possible drug binding sites were determined by homology modelling. PMID:26921192

  3. Contact lens-induced edema in vitro--amelioration by lactate dehydrogenase inhibitors.

    PubMed

    Rohde, M D; Huff, J W

    1986-10-01

    Isolated rabbit corneas bathed in Krebs-bicarbonate Ringer solution were observed for thickness changes after a 90 minute equilibration period. Control corneas swelled an average of 0.5 micron/hr, and placement of a polymethylmechacrylate (PMMA) contact lens on the epithelial surface caused the corneas to swell 24.5 microns/hr, an effect similar to 0.5 mM epithelial cyanide exposure. The pronounced swelling induced by PMMA lens placement was much less however, in the epithelial presence of 3.2 mM sodium oxalate (3.22 microns/hr) or 3.2 mM sodium oxamate (5.38 microns/hr). An equiosmotic excess of 4.8 mM NaCl was least active (15.89 microns/hr). On normal isolated corneas (without contact lenses), the Ringer containing an excess of 4.8 mM NaCl significantly deswelled the corneas (-13.44 microns/hr), which contrasted with oxalate and oxamate containing Ringer solutions (1.17 and 1.33 micron/hr respectively). The present study supports the notion that contact lens-induced edema results from stromal lactate accumulation, and suggests a potential alternative to osmotic therapy for its amelioration. These LDH inhibitors, in the concentrations used, have no acute osmotic or toxic effect on normal corneas in vitro. PMID:3769523

  4. Both Creatine and Its Product Phosphocreatine Reduce Oxidative Stress and Afford Neuroprotection in an In Vitro Parkinson’s Model

    PubMed Central

    Martín-de-Saavedra, Maria D.; Romero, Alejandro; Egea, Javier; Ludka, Fabiana K.; Tasca, Carla I.; Farina, Marcelo; Rodrigues, Ana Lúcia S.; López, Manuela G.

    2014-01-01

    Creatine is the substrate for creatine kinase in the synthesis of phosphocreatine (PCr). This energetic system is endowed of antioxidant and neuroprotective properties and plays a pivotal role in brain energy homeostasis. The purpose of this study was to investigate the neuroprotective effect of creatine and PCr against 6-hydroxydopamine (6-OHDA)-induced mitochondrial dysfunction and cell death in rat striatal slices, used as an in vitro Parkinson’s model. The possible involvement of the signaling pathway mediated by phosphatidylinositol-3 kinase (PI3K), protein kinase B (Akt), and glycogen synthase kinase-3β (GSK3β) was also evaluated. Exposure of striatal slices to 6-OHDA caused a significant disruption of the cellular homeostasis measured as 3-(4,5 dimethylthiazol-2-yl)-2,5-diphenyl-tetrazolium bromide reduction, lactate dehydrogenase release, and tyrosine hydroxylase levels. 6-OHDA exposure increased the levels of reactive oxygen species and thiobarbituric acid reactive substances production and decreased mitochondrial membrane potential in rat striatal slices. Furthermore, 6-OHDA decreased the phosphorylation of Akt (Serine473) and GSK3β (Serine9). Coincubation with 6-OHDA and creatine or PCr reduced the effects of 6-OHDA toxicity. The protective effect afforded by creatine or PCr against 6-OHDA-induced toxicity was reversed by the PI3K inhibitor LY294002. In conclusion, creatine and PCr minimize oxidative stress in striatum to afford neuroprotection of dopaminergic neurons. PMID:25424428

  5. An atypical distribution of lactate dehydrogenase isoenzymes in the hooded seal (Cystophora cristata) brain may reflect a biochemical adaptation to diving.

    PubMed

    Hoff, Mariana Leivas Müller; Fabrizius, Andrej; Folkow, Lars P; Burmester, Thorsten

    2016-04-01

    The brains of some diving mammals can withstand periods of severe hypoxia without signs of deleterious effects. This may in part be due to an enhanced cerebral capacity for anaerobic energy production. Here, we have tested this hypothesis by comparing various parameters of the lactate dehydrogenase (LDH) in the brain of the hooded seal (Cystophora cristata) with those in the brains of the ferret (Mustela putorius furo) and mouse (Mus musculus). We found that mRNA and protein expression of lactate dehydrogenase a (LDHA) and lactate dehydrogenase b (LDHB), and also the LDH activity were significantly higher in the ferret brain than in brains of the hooded seal and the mouse (p < 0.0001). No conspicuous differences in the LDHA and LDHB sequences were observed. There was also no difference in the buffering capacities of the brains. Thus, an enhanced capacity for anaerobic energy production likely does not explain the higher hypoxia tolerance of the seal brain. However, the brain of the hooded seal had higher relative levels of LDHB isoenzymes (LDH1 and LDH2) compared to the non-diving mammals. Moreover, immunofluorescence studies showed more pronounced co-localization of LDHB and glial fibrillary acidic protein in the cortex of the hooded seal. Since LDHB isoenzymes primarily catalyze the conversion of lactate to pyruvate, this finding suggests that the contribution of astrocytes to the brain aerobic metabolism is higher in the hooded seal than in non-diving species. The cerebral tolerance of the hooded seal to hypoxia may therefore partly rely on different LDH isoenzymes distribution. PMID:26820264

  6. Lactate dehydrogenase release as an indicator of dithranol-induced membrane injury in cultured human keratinocytes. A time profile study.

    PubMed

    Bonnekoh, B; Farkas, B; Geisel, J; Mahrle, G

    1990-01-01

    HaCaT cells, a rapidly multiplying human keratinocyte line, were tested for their sensitivity to antipsoriatic dithranol with regard to classical proliferation parameters and for the drug's action on the plasma membrane integrity by the dose- and time-dependent release of cytosolic lactate dehydrogenase (LDH). In the case of 3H thymidine as well as 14C amino acid incorporation the 50% inhibition concentration (IC50) was 0.2 microM dithranol 24 h after initial exposure to the drug. For protein content of attached cells the IC50 proved to be greater than 3.0 microM. Using 0.3, 1.0 and 3.0 microM dithranol, significant (p less than 0.05) dose dependent LDH release of 0.866 +/- 0.387, 1.842 +/- 1.127 and 2.938 +/- 1.635 mU per hour and cm2 confluent culture area was measured between the 5th and the 24th hour, compared to an acetone control of 0.504 +/- 0.299 mU/h x cm2. Between the 2nd and the 4th hour as well as from the 25th to the 48th hour and the 49th to the 72nd hour the LDH release after dithranol treatment did not exceed the control value. In accordance with these findings dose-dependent morphological signs of cell injury were detected by phase contrast microscopy beyond the 4th hour. The data reveal that: HaCaT cells are a very sensitive target for the antiproliferative action of dithranol; the drug causes considerable plasma membrane damage even at concentrations as low as 0.3 microM; and this membrane damage becomes evident after a latency of at least 4 h and for a limited period of up to 24 h. PMID:2221984

  7. Impact of Pre-Treatment Lactate Dehydrogenase Levels on Prognosis and Bevacizumab Efficacy in Patients with Metastatic Colorectal Cancer

    PubMed Central

    Passardi, Alessandro; Scarpi, Emanuela; Tamberi, Stefano; Cavanna, Luigi; Tassinari, Davide; Fontana, Annalisa; Pini, Sara; Bernardini, Ilaria; Accettura, Caterina; Ulivi, Paola; Frassineti, Giovanni Luca; Amadori, Dino

    2015-01-01

    Background To investigate the impact of pre-treatment lactate dehydrogenase (LDH) levels on the outcome of patients with metastatic colorectal cancer treated with first-line chemotherapy with or without the anti-VEGF monoclonal antibody, bevacizumab, in a phase III prospective multicentre randomized ITACa (Italian Trial in Advanced Colorectal Cancer) trial. Methods Three hundred and seventy patients enrolled onto the ITACa first-line trial were considered for this study, 176 receiving chemotherapy (either FOLFIRI or FOLFOX) plus bevacizumab and 194 receiving chemotherapy only. Pre-treatment LDH levels were evaluated to identify a potential correlation with progression-free survival (PFS), overall survival (OS) and objective response rate. Results Information on pre-treatment LDH levels was available for 344 patients. High LDH levels were predictive of a lower median PFS (8.1 months vs. 9.2 months, p< 0.0001) and median OS (16.1 months vs. 25.2 months, p< 0.0001) in the overall population. In the chemotherapy plus bevacizumab group, median PFS was 9.1 and 9.8 months in patients with high LDH and low LDH, respectively (p= 0.073), whereas in the chemotherapy-only arm it was 6.9 and 9.1 months, respectively (p < 0.0001). In patients with high LDH, the addition of bevacizumab to chemotherapy led to a reduction in the rate of progressive disease (16.4 vs. 30.5%, p= 0.081) and to a prolonged PFS (p= 0.028). Conclusion A high LDH value was confirmed as a marker of poor prognosis. Bevacizumab reduced the progressive disease rate and improved PFS in the high-LDH subgroup, making serum LDH a potentially effective an easily available and marker to select patients who benefit from bevacizumab. Trial Registration NCT01878422 ClinicalTrials.gov PMID:26244985

  8. Elevated lactate dehydrogenase activity and increased cardiovascular mortality in the arsenic-endemic areas of southwestern Taiwan

    SciTech Connect

    Liao, Ya-Tang; Graduate Institute of Epidemiology and Preventive Medicine, College of Public Health, National Taiwan University, Taiwan; Genomics Research Center, Academia Sinica, Taiwan ; Chen, Chien-Jen; Genomics Research Center, Academia Sinica, Taiwan ; Li, Wan-Fen; Hsu, Ling-I; Tsai, Li-Yu; Huang, Yeou-Lih; Sun, Chien-Wen; Chen, Wei J.; Wang, Shu-Li; Department of Public Health, College of Public Health, China Medical University, Taichung, Taiwan

    2012-08-01

    Arsenic ingestion has been linked to increasing global prevalence of and mortality from cardiovascular disease (CVD); arsenic can be removed from drinking water to reduce related health effects. Lactate dehydrogenase (LDH) is used for the evaluation of acute arsenic toxicity in vivo and in vitro, but it is not validated for the evaluation of long-term, chronic arsenic exposure. The present study examined the long-term effect of chronic arsenic exposure on CVD and serum LDH levels, after consideration of arsenic metabolism capacity. A total of 380 subjects from an arseniasis-endemic area and 303 from a non-endemic area of southwestern Taiwan were recruited in 2002. Various urinary arsenic species were analyzed using high-performance liquid chromatography (HPLC) and hydride generation systems. Fasting serum was used for quantitative determination of the total LDH activity. A significant dose–response relationship was observed between arsenic exposure and LDH elevation, independent of urinary arsenic profiles (P < 0.001). Furthermore, abnormal LDH elevation was associated with CVD mortality after adjustment for Framingham risk scores for 10-year CVD and arsenic exposure (hazard ratio, 3.98; 95% confidence interval, 1.07–14.81). LDH was elevated in subjects with arsenic exposure in a dose-dependent manner. LDH is a marker of arsenic toxicity associated with CVD mortality. Results of this study have important implications for use in ascertaining long-term arsenic exposure risk of CVD. -- Highlights: ► We showed that arsenic exposure was correlated with LDH elevation. ► LDH elevation was related to arsenic methylation capacity. ► Abnormal LDH elevation can be a marker of susceptibility to CVD mortality.

  9. Prognostic value of ferritin, neuron-specific enolase, lactate dehydrogenase, and urinary and plasmatic catecholamine metabolites in children with neuroblastoma

    PubMed Central

    Cangemi, Giuliana; Reggiardo, Giorgio; Barco, Sebastiano; Barbagallo, Laura; Conte, Massimo; D’Angelo, Paolo; Bianchi, Maurizio; Favre, Claudio; Galleni, Barbara; Melioli, Giovanni; Haupt, Riccardo; Garaventa, Alberto; Corrias, Maria V

    2012-01-01

    Different plasma and urinary parameters have been tested as valuable prognostic markers for children with neuroblastoma (NB), but conclusive results from multivariate analyses are still lacking. Samples collected at diagnosis from 505 patients diagnosed in Italy between June 1994 and November 2010 were analyzed at the Italian reference laboratory according to standard methodologies. Patient clinical data were retrieved from the Italian NB Registry. For statistical analysis, patients were grouped according to stage, age, MYCN status, and outcome. Cumulative survival was calculated by the Kaplan–Meier procedure using the first quartile of the marker distribution as a cut-off value to stratify the patients. Multivariate analysis was performed by the Cox regression model by considering only the significant variables. When the entire cohort of patients was considered, none of the different parameters had an independent prognostic value. However, in patients with localized disease without MYCN amplification the significant positive associations between urinary and plasmatic vanillylmandelic acid (VMA)/homovanillic acid (HVA) ratio and a better prognosis remained significant (P < 0.05 and P < 0.01, respectively), as well as, the positive association between high lactate dehydrogenase (LDH) values and a worse prognosis (P < 0.001). Moreover, in stage 4 patients without MYCN amplification, neuron-specific enolase levels above 200 ng/mL and LDH levels above 2500 IU/mL maintained their significant association with a worse outcome (P = 0.01 and P = 0.0001, respectively). In conclusion, LDH had an independent prognostic value in patients of all stages without MYCN amplification. Moreover, the urinary and plasmatic VMA/HVA ratio was an independent predictor of prognosis in patients with localized disease without MYCN amplification. Since LDH and catecholamine metabolites are measured in all patients at diagnosis, these findings may be helpful for an easy, cost-effective, patient risk stratification. PMID:23226699

  10. Prognostic value of ferritin, neuron-specific enolase, lactate dehydrogenase, and urinary and plasmatic catecholamine metabolites in children with neuroblastoma.

    PubMed

    Cangemi, Giuliana; Reggiardo, Giorgio; Barco, Sebastiano; Barbagallo, Laura; Conte, Massimo; D'Angelo, Paolo; Bianchi, Maurizio; Favre, Claudio; Galleni, Barbara; Melioli, Giovanni; Haupt, Riccardo; Garaventa, Alberto; Corrias, Maria V

    2012-01-01

    Different plasma and urinary parameters have been tested as valuable prognostic markers for children with neuroblastoma (NB), but conclusive results from multivariate analyses are still lacking. Samples collected at diagnosis from 505 patients diagnosed in Italy between June 1994 and November 2010 were analyzed at the Italian reference laboratory according to standard methodologies. Patient clinical data were retrieved from the Italian NB Registry. For statistical analysis, patients were grouped according to stage, age, MYCN status, and outcome. Cumulative survival was calculated by the Kaplan-Meier procedure using the first quartile of the marker distribution as a cut-off value to stratify the patients. Multivariate analysis was performed by the Cox regression model by considering only the significant variables. When the entire cohort of patients was considered, none of the different parameters had an independent prognostic value. However, in patients with localized disease without MYCN amplification the significant positive associations between urinary and plasmatic vanillylmandelic acid (VMA)/homovanillic acid (HVA) ratio and a better prognosis remained significant (P < 0.05 and P < 0.01, respectively), as well as, the positive association between high lactate dehydrogenase (LDH) values and a worse prognosis (P < 0.001). Moreover, in stage 4 patients without MYCN amplification, neuron-specific enolase levels above 200 ng/mL and LDH levels above 2500 IU/mL maintained their significant association with a worse outcome (P = 0.01 and P = 0.0001, respectively). In conclusion, LDH had an independent prognostic value in patients of all stages without MYCN amplification. Moreover, the urinary and plasmatic VMA/HVA ratio was an independent predictor of prognosis in patients with localized disease without MYCN amplification. Since LDH and catecholamine metabolites are measured in all patients at diagnosis, these findings may be helpful for an easy, cost-effective, patient risk stratification. PMID:23226699

  11. Benefit from thoracic radiotherapy in patients with extensive-disease small-cell lung cancer with elevated lactate dehydrogenase

    PubMed Central

    Qin, Tao; Zhou, Ningning; Zeng, Yin-duo; Dinglin, Xiaoxiao; Zhao, Yuanyuan; Liu, Huai; Chen, Likun

    2016-01-01

    Background High lactate dehydrogenase (LDH) is associated with a large tumor burden in extensive-disease small-cell lung cancer (ED-SCLC). This study evaluated the benefit of additional thoracic radiotherapy (TRT) in patients with ED-SCLC with elevated LDH. Methods We analyzed 94 patients with ED-SCLC and evaluated LDH at Sun Yat-sen University Cancer Center during the period between January 2000 and March 2010. Patients were divided into two groups according to whether TRT was received. Survival was evaluated by the Kaplan–Meier method and Cox’s regression analysis. Results The median age of the 94 patients with ED-SCLC was 58.5 years. The main metastatic sites included the liver, bone, brain, and adrenal glands. The response rate in the TRT group was 46.9%. There were 32 patients (34.04%) receiving TRT and 5.3% receiving prophylactic cranial irradiation. The median survival time reached 10 months (95% confidence interval: 8.22, 11.78 months), and the 1-, 2-, and 5-year survival rates were 43.6%, 11.7%, and 2.1%, respectively. There was a significant difference in the median progression-free survival (PFS) and overall survival (OS) between the TRT group and the no TRT group (PFS: 9.0 months vs 6.0 months, P=0.018; OS: 13.0 months vs 9.0 months, P=0.006). Conclusion The use of TRT improves the survival of patients with ED-SCLC. Future studies should use the LDH level for categorizing patients for treatment. PMID:27042102

  12. Pyruvate Kinase M2 and Lactate Dehydrogenase A Are Overexpressed in Pancreatic Cancer and Correlate with Poor Outcome

    PubMed Central

    Mohammad, Goran Hamid; Olde Damink, S. W. M.; Malago, Massimo; Dhar, Dipok Kumar; Pereira, Stephen P.

    2016-01-01

    Pancreatic cancer has a 5-year survival rate of less than 4%. Despite advances in diagnostic technology, pancreatic cancer continues to be diagnosed at a late and incurable stage. Accurate biomarkers for early diagnosis and to predict treatment response are urgently needed. Since alteration of glucose metabolism is one of the hallmarks of cancer cells, we proposed that pyruvate kinase type M2 (M2PK) and lactate dehydrogenase A (LDHA) enzymes could represent novel diagnostic markers and potential therapeutic targets in pancreatic cancer. In 266 tissue sections from normal pancreas, pancreatic cystic neoplasms, pancreatic intraepithelial neoplasia (PanIN) and cancer, we evaluated the expression of PKM2, LDHA, Ki-67 and CD8+ by immunohistochemistry and correlated these markers with clinicopathological characteristics and patient survival. PKM2 and LDHA expression was also assessed by Western blot in 10 human pancreatic cancer cell lines. PKM2 expression increased progressively from cyst through PanIN to cancer, whereas LDHA was overexpressed throughout the carcinogenic process. All but one cell line showed high expression of both proteins. Patients with strong PKM2 and LDHA expression had significantly worse survival than those with weak PKM2 and/or LDHA expression (7.0 months vs. 27.9 months, respectively, p = 0.003, log rank test). The expression of both PKM2 and LDHA correlated directly with Ki-67 expression, and inversely with intratumoral CD8+ cell count. PKM2 was significantly overexpressed in poorly differentiated tumours and both PKM2 and LDHA were overexpressed in larger tumours. Multivariable analysis showed that combined expression of PKM2 and LDHA was an independent poor prognostic marker for survival. In conclusion, our results demonstrate a high expression pattern of two major glycolytic enzymes during pancreatic carcinogenesis, with increased expression in aggressive tumours and a significant adverse effect on survival. PMID:26989901

  13. Electron acquisition system constructed from an NAD-independent D-lactate dehydrogenase and cytochrome c2 in Rhodopseudomonas palustris No. 7.

    PubMed

    Horikiri, Shunsuke; Aizawa, Yoshiyuki; Kai, Taiki; Amachi, Seigo; Shinoyama, Hirofumi; Fujii, Takaaki

    2004-03-01

    The activities of NAD-independent D- and L-lactate dehydrogenases (D-LDH, L-LDH) were detected in Rhodopseudomonas palustris No. 7 grown photoanaerobically on lactate. One of these enzymes, D-LDH, was purified as an electrophoretically homogeneous protein (M(r), about 235,000; subunit M(r) about 57,000). The pI was 5.0. The optimum pH and temperature of the enzyme were pH 8.5 and 50 degrees C, respectively. The Km of the enzyme for D-lactate was 0.8 mM. The enzyme had narrow substrate specificity (D-lactate and DL-2-hydroxybutyrate). The enzymatic activity was competitively inhibited by oxalate (Ki, 0.12 mM). The enzyme contained a FAD cofactor. Cytochrome c(2) was purified from strain No. 7 as an electrophoretically homogeneous protein. Its pI was 9.4. Cytochrome c(2) was reduced by incubating with D-LDH and D-lactate. PMID:15056881

  14. Simultaneous production of 3-hydroxypropionic acid and 1,3-propanediol from glycerol using resting cells of the lactate dehydrogenase-deficient recombinant Klebsiella pneumoniae overexpressing an aldehyde dehydrogenase.

    PubMed

    Kumar, Vinod; Sankaranarayanan, Mugesh; Durgapal, Meetu; Zhou, Shengfang; Ko, Yeounjoo; Ashok, Somasundar; Sarkar, Ritam; Park, Sunghoon

    2013-05-01

    In the present study, the lactate dehydrogenase-deficient (ldhA(-)) recombinant Klebsiella pneumoniae overexpressing an ALDH (KGSADH) was developed and the co-production of 3-HP and PDO from glycerol by this recombinant under resting cell conditions was examined. The new recombinant did not produce any appreciable lactate, which seriously inhibits the production of 3-HP and PDO. The final titers of 3-HP and PDO by the ldhA(-) recombinant strain at 60 h were 252.2 mM and 308.7 mM, respectively, which were improved by approximately 30% and 50%, respectively, compared to those by the counterpart recombinant strain, which was the wild type for ldhA. In addition, after deleting ldhA, the cumulative yield on glycerol and specific production rate of these two metabolites (3-HP and PDO) were enhanced by 41.4% and 52%, respectively. PMID:23228456

  15. Synthesis and application of a photoaffinity analog of nicotinamide adenosine dinucleotide: Identification of the active sites of glutamate and lactate dehydrogenases

    SciTech Connect

    Kim, H.

    1990-01-01

    A photoaffinity analog of NAD{sup +} has been synthesized by chemically coupling ({sup 32}P)2-azido-AMP and NMN{sup +} to produce ({sup 32}P)nicotinamide 2-azidoadenosine dinucleotide (2-azido-NAD{sup +}). The utility of 2-azido-NAD{sup +} as an effective active-site-directed photoprobe was demonstrated using bovine liver glutamate dehydrogenase and porcine muscle lactate dehydrogenase as model enzymes. In the absence of ultraviolet light 2-azido-NAD{sup +} is a substrate for these enzymes. The specificity of active site labeling was demonstrated by photoinhibition, saturation and competition experiments. The active sites of these enzymes were identified utilizing 2-azido-NAD{sup +}. The immobilized boronate column chromatography was used to isolate the photolabeled peptides. The results demonstrate that the photoaffinity analog of NAD{sup +} has potential application as a probe to characterize NAD{sup +}binding proteins and to identify the active sites of these proteins.

  16. A novel polyclonal antibody-based sandwich ELISA for detection of Plasmodium vivax developed from two lactate dehydrogenase protein segments

    PubMed Central

    2014-01-01

    Background Immunoassays for Plasmodium detection are, presently, most frequently based on monoclonal antibodies (MAbs); Polyclonal antibodies (PAbs), which are cheaper to develop and manufacture, are much less frequently used. In the present study we describe a sandwich ELISA assay which is capable of detecting P. vivax Lactate Dehydrogenase (LDH) in clinical blood samples, without cross reacting with those infected with P. falciparum. Methods Two recombinant proteins were produced from different regions of the P. vivax LDH gene. Two sandwich ELISA assay were then designed: One which uses mouse anti-LDH 1-43aa PAbs as primary antibodies (“Test 1”) and another which uses anti-LDH 35-305aa PAbs (“Test 2”) as the primary antibodies. Rabbit anti-LDH 1-43aa PAbs were used as capture antibodies in both ELISA assays. Blood samples taken from P. vivax and P. falciparum infected patients (confirmed by light microscopy) were analysed using both tests. Results “Test 2” performed better at detecting microscopy-positive blood samples when compared to “Test 1”, identifying 131 of 154 positive samples (85%); 85 positives (55%) were identified using “test 1”. “Test 1” produced one false positive sample (from the 20 malaria-free control) blood samples; “test 2” produced none. Kappa coefficient analysis of the results produced a value of 0.267 when microscope-positive blood smears were compared with “test 1”, but 0.734 when microscope-positive blood smears were compared with the results from “test 2”. Positive predictive value (PPV) and negative predictive value (NPV) were observed to be 98% and 22% respectively, for “Test 1”, and 99% and 45%, for “test 2”. No cross reactivity was detected with P. falciparum positive blood samples (n = 15) with either test assay. Conclusion Both tests detected P. vivax infected blood and showed no evidence of cross-reacting with P. falciparum. Further studies will need to be conducted to establish the full potential of this technique for malaria diagnostics. As well as representing a promising new cost-effective novel technique for P. vivax diagnosis and research, the method for developing this assay also highlights the potential for PAb-based strategies for diagnostics in general. PMID:24475751

  17. Selective antibody neutralization prevents neuropathogenic lactate dehydrogenase-elevating virus from causing paralytic disease in immunocompetent mice.

    PubMed

    Chen, Z; Li, K; Rowland, R R; Plagemann, P G

    1999-04-01

    Neuropathogenic lactate dehydrogenase-elevating viruses (LDV) cytocidally infect anterior horn neurons in C58 and AKR mice via interaction with endogenous murine retroviruses to cause a paralytic disease, age-dependent poliomyelitis (ADPM). The induction of ADPM requires a suppressed host immune system as a result of old age, genetic defects (such as nude mice) or any immunosuppressive treatment. Previous results have shown that the infection of anterior horn neurons by neuropathogenic LDV isolates and the subsequent development of ADPM are prevented by anti-LDV antibodies either induced actively during infection or when passively administered. However, the mechanism of protection was unclear since both neutralizing and non-neutralizing polyclonal antibodies seemed protective, whereas only neutralizing monoclonal antibodies were protective. Furthermore, the protection of motor neurons from infection occurred in the absence of any apparent effect on LDV replication in a subpopulation of macrophages known to be the primary permissive host cells. These paradoxes have now been resolved. We have recently reported that the neuropathogenic LDV isolates contain both neuropathogenic and non-neuropathogenic quasispecies that differ in their ability to establish a high viremia persistent infection. Using biological clones of both neuropathogenic and non-neuropathogenic quasispecies, we now demonstrate that both replicate in the same subpopulation of permissive macrophages, but that the neuropathogenic quasispecies are about 100 times more susceptible to in vitro antibody neutralization than the non-neuropathogenic ones, and that antibodies that neutralize the neuropathogenic but not the non-neuropathogenic quasispecies develop as soon as 7 days after infection with neuropathogenic LDVs and selectively suppress the replication of the neuropathogenic LDVs in vivo in FVB, BALB/c, C57 BL/6 and C58 mice. The previously observed lack of neutralizing effect of early polyclonal anti-LDV antibodies and the apparent ineffective antibody control of LDV replication in macrophages were due to outgrowth of the non-neuropathogenic quasispecies that are also present in the neuropathogenic LDV inoculum and are highly resistant to antibody neutralization. Using cloned neuropathogenic LDV quasispecies, we demonstrate a clear relationship in the development of neutralizing antibodies, replication suppression of the neuropathogenic LDVs and the prevention of ADPM in C58 mice. Our results therefore establish an inseparable relationship between the neuron-protective effect of an antibody and its neutralization of the neuropathogenic LDV quasispecies and explain why neuropathogenic LDVs cause paralytic disease only in immunosuppressed mice. PMID:10321985

  18. Lactate dehydrogenase test

    MedlinePlus

    ... value range is 105 - 333 IU/L (international units per liter). Normal value ranges may vary slightly among different laboratories. Some labs use different measurements or test different samples. Talk to your doctor about the ...

  19. Changes in milk yield, lactate dehydrogenase, milking frequency, and interquarter yield ratio persist for up to 8 weeks after antibiotic treatment of mastitis.

    PubMed

    Fogsgaard, K K; Løvendahl, P; Bennedsgaard, T W; Østergaard, S

    2015-11-01

    Within the dairy industry, the appearance of milk and withdrawal time due to antibiotic residuals in the milk are used to determine recovery status after cases of treated mastitis. However, both milk production and dairy cow behavior have been shown to be affected after the normalization of milk appearance, indicating that animals may not have fully recovered. The aim of the present study was to describe the changes in milk yield, lactate dehydrogenase activity, milking frequency, and interquarter yield ratio (defined as the coefficient of variation between the active quarters) after cases of naturally occurring mastitis with special focus on the recovery period after antibiotic treatment. A second aim was to examine whether these changes were affected by the pathogens present at the time of mastitis diagnosis. This retrospective study was based on a cohort data set including 1,032 lactations from 795 dairy cows kept on 2 Danish farms and milked by an automatic milking system. A total of 174 treated mastitis cases were compared with nontreated control cows from 5 wk before treatment and until 8 wk after. Treated mastitis resulted in reduced milk yield, elevated lactate dehydrogenase activity, lower milking frequency, and elevated interquarter yield ratio. Within these measures, deviations from baseline levels and from the control cows were found as early as 1 to 3 wk before the antibiotic treatment and peaked around the days of treatment. In some cases, the mastitic cows returned to premastitis levels, whereas in others they remained affected throughout the rest of the observation period. To correctly estimate the effects of treated mastitis and the recovery status of cows, it is important to take the individual cow into account and not only compare with herd levels, as this might mask the true degree of the changes. The effects on each outcome variable depended on the involved pathogen and differences were found between primiparous cows and older animals. However, in general, the changes in milk production, lactate dehydrogenase activity, and interquarter yield ratio showed parallels, suggesting that the recovery period continued for weeks after antibiotic treatment. These results call for further investigation into management of mastitic dairy cows to optimize recovery, limit milk loss, and ensure animal welfare during the period after mastitis. PMID:26364092

  20. Low potential detection of NADH based on Fe₃O₄ nanoparticles/multiwalled carbon nanotubes composite: fabrication of integrated dehydrogenase-based lactate biosensor.

    PubMed

    Teymourian, Hazhir; Salimi, Abdollah; Hallaj, Rahman

    2012-03-15

    Fe(3)O(4) magnetic nanoparticles were in situ loaded on the surface of multiwalled carbon nanotubes (MWCNTs) by a simple coprecipitation procedure. The resulting Fe(3)O(4)/MWCNTs nanocomposite brings new capabilities for electrochemical sensing by combining the advantages of Fe(3)O(4) magnetic nanoparticles and MWCNTs. It was found that Fe(3)O(4) has redox properties similar to those of frequently used mediators used for electron transfer between NADH and electrode. The cyclic voltammetric results indicated the ability of Fe(3)O(4)/MWCNTs modified GC electrode to catalyze the oxidation of NADH at a very low potential (0.0 mV vs. Ag/AgCl) and subsequently, a substantial decrease in the overpotential by about 650 mV compared with the bare GC electrode. The catalytic oxidation current allows the stable and selective amperometric detection of NADH at an applied potential of 0.0 mV (Ag/AgCl) with a detection limit of 0.3 μM and linear response up to 300 μM. This modified electrode can be used as an efficient transducer in the design of biosensors based on coupled dehydrogenase enzymes. Lactate dehydrogenase (LDH) and NAD(+) were subsequently immobilized onto the Fe(3)O(4)/MWCNTs nanocomposite film by covalent bond formation between the amine groups of enzyme or NAD(+) and the carboxylic acid groups of the Fe(3)O(4)/MWCNT film. Differential pulse voltammetric detection of lactate on Fe(3)O(4)/MWCNT/LDH/NAD(+) modified GC electrode gives linear responses over the concentration range of 50-500 μM with the detection limit of 5 μM and sensitivity of 7.67 μA mM(-1). Furthermore, the applicability of the sensor for the analysis of lactate concentration in human serum samples has been successfully demonstrated. PMID:22230696

  1. Interaction of the membrane-bound D-lactate dehydrogenase of Escherichia coli with phospholipid vesicles and reconstitution of activity using a spin-labeled fatty acid as an electron acceptor: A magnetic resonance and biochemical study

    SciTech Connect

    Truong, Hoaithu N.; Pratt, E.A.; Ho, Chien )

    1991-04-23

    The interaction with phospholipid vesicles of the membrane-bound respiratory enzyme D-lactate dehydrogenase of Escherichia coli has been studied. Proteolytic digestion studies show that D-lactate dehydrogenase is protected from trypsin digestion to a larger extent when it interacts with phosphatidylglycerol than with phosphatidylcholine vesicles. Wild-type D-lactate dehydrogenase and mutants in which an additional tryptophan is substituted in selected areas by site-specific oligonucleotide-directed mutagenesis have been labeled with 5-fluorotryptophan. {sup 19}F nuclear magnetic resonance studies of the interaction of these labeled enzymes with small unilamellar phospholipid vesicles show that Trp 243, 340, and 361 are exposed to the lipid phase, while Trp 384, 407, and 567 are accessible to the external aqueous phase. Reconstitution of enzymatic activity in phospholipid vesicles has been studied by adding enzyme and substrate to phospholipid vesicles containing a spin-labeled fatty acid as an electron acceptor. The reduction of the doxyl group of the spin-labeled fatty acid has been monitored indirectly by nuclear magnetic resonance and directly by electron paramagnetic resonance. These results indicate that an artificial electron-transfer system can be created by mixing D-lactate dehydrogenase and D-lactate together with phospholipid vesicles containing spin-labeled fatty acids.

  2. Evaluation of three parasite lactate dehydrogenase-based rapid diagnostic tests for the diagnosis of falciparum and vivax malaria

    PubMed Central

    Ashley, Elizabeth A; Touabi, Malek; Ahrer, Margareta; Hutagalung, Robert; Htun, Khayae; Luchavez, Jennifer; Dureza, Christine; Proux, Stephane; Leimanis, Mara; Lwin, Myo Min; Koscalova, Alena; Comte, Eric; Hamade, Prudence; Page, Anne-Laure; Nosten, François; Guerin, Philippe J

    2009-01-01

    Background In areas where non-falciparum malaria is common rapid diagnostic tests (RDTs) capable of distinguishing malaria species reliably are needed. Such tests are often based on the detection of parasite lactate dehydrogenase (pLDH). Methods In Dawei, southern Myanmar, three pLDH based RDTs (CareStart™ Malaria pLDH (Pan), CareStart™ Malaria pLDH (Pan, Pf) and OptiMAL-IT®)were evaluated in patients presenting with clinically suspected malaria. Each RDT was read independently by two readers. A subset of patients with microscopically confirmed malaria had their RDTs repeated on days 2, 7 and then weekly until negative. At the end of the study, samples of study batches were sent for heat stability testing. Results Between August and November 2007, 1004 patients aged between 1 and 93 years were enrolled in the study. Slide microscopy (the reference standard) diagnosed 213 Plasmodium vivax (Pv) monoinfections, 98 Plasmodium falciparum (Pf) mono-infections and no malaria in 650 cases. The sensitivities (sens) and specificities (spec), of the RDTs for the detection of malaria were- CareStart Malaria™ pLDH (Pan) test: sens 89.1% [CI95 84.2-92.6], spec 97.6% [CI95 96.5-98.4] OptiMal-IT®: Pf+/- other species detection: sens 95.2% [CI95 87.5-98.2], spec 94.7% [CI95 93.3-95.8]; non-Pf detection alone: sens 89.6% [CI95 83.6-93.6], spec 96.5% [CI95 94.8-97.7] CareStart Malaria™ pLDH (Pan, Pf): Pf+/- other species: sens 93.5% [CI9585.4-97.3], spec 97.4% [95.9-98.3]; non-Pf: sens 78.5% [CI9571.1-84.4], spec 97.8% [CI95 96.3-98.7] Inter-observer agreement was excellent for all tests (kappa > 0.9). The median time for the RDTs to become negative was two days for the CareStart™ Malaria tests and seven days for OptiMAL-IT®. Tests were heat stable up to 90 days except for OptiMAL-IT® (Pf specific pLDH stable to day 20 at 35°C). Conclusion None of the pLDH-based RDTs evaluated was able to detect non-falciparum malaria with high sensitivity, particularly at low parasitaemias. OptiMAL-IT® performed best overall and would perform best in an area of high malaria prevalence among screened fever cases. However, heat stability was unacceptable and the number of steps to perform this test is a significant drawback in the field. A reliable, heat-stable, highly sensitive RDT, capable of diagnosing all Plasmodium species has yet to be identified. PMID:19860920

  3. d-Lactate Dehydrogenase Gene (ldhD) Inactivation and Resulting Metabolic Effects in the Lactobacillus johnsonii Strains La1 and N312

    PubMed Central

    Lapierre, Luciane; Germond, Jacques-Edouard; Ott, Andreas; Delley, Michele; Mollet, Beat

    1999-01-01

    Lactobacillus johnsonii La1, a probiotic bacterium with demonstrated health effects, grows in milk, where it ferments lactose to d- and l-lactate in a 60:40% ratio. The d-lactate dehydrogenase (D-LDH) gene (ldhD) of this strain was isolated, and an in vitro-truncated copy of that gene was used to inactivate the genomic copy in two strains, La1 and N312, by gene replacement. For that, an 8-bp deletion was generated within the cloned ldhD gene to inactivate its function. The plasmid containing the altered ldhD was transferred to L. johnsonii via conjugative comobilization with Lactococcus lactis carrying pAMβ1. Crossover integrations of the plasmid at the genomic ldhD site were selected, and appropriate resolution of the cointegrate structures resulted in mutants that had lost the plasmid and in which the original ldhD was replaced by the truncated copy. These mutants completely lacked D-LDH activity. Nevertheless, the lower remaining L-LDH activity of the cells was sufficient to reroute most of the accumulating pyruvate to l-lactate. Only a marginal increase in production of the secondary end products acetaldehyde, diacetyl, and acetoin was observed. It can be concluded that in L. johnsonii D- and L-LDH are present in substantial excess for their role to eliminate pyruvate and regenerate NAD+ and that accumulated pyruvate is therefore not easily redirected in high amounts to secondary metabolic routes. PMID:10473408

  4. The effect of creatine supplementation upon inflammatory and muscle soreness markers after a 30km race.

    PubMed

    Santos, R V T; Bassit, R A; Caperuto, E C; Costa Rosa, L F B P

    2004-09-01

    We have evaluated the effect of a creatine supplementation protocol upon inflammatory and muscle soreness markers: creatine kinase (CK), lactate dehydrogenase (LDH), prostaglandin E2) (PGE2) and tumor necrosis factor-alpha (TNF-alpha) after running 30km. Runners with previously experience in running marathons, with their personal best between 2.5-3h were supplemented for 5 days prior to the 30km race with 4 doses of 5g of creatine and 15g of maltodextrine per day while the control group received the same amount of maltodextrine. Pre-race blood samples were collected immediately before running the 30km, and 24h after the end of the test (the post-race samples). After the test, athletes from the control group presented an increase in plasma CK (4.4-fold), LDH (43%), PGE2 6.6-fold) and TNF-alpha (2.34-fold) concentrations, indicating a high level of cell injury and inflammation. Creatine supplementation attenuated the changes observed for CK (by 19%), PGE2 and TNF-alpha (by 60.9% and 33.7%, respectively, p<0.05) and abolished the increase in LDH plasma concentration observed after running 30km, The athletes did not present any side effects such as cramping, dehydration or diarrhea, neither during the period of supplementation, nor during the 30km race. All the athletes finished the race in a time equivalent to their personal best +/- 5.8%. These results indicate that creatine supplementation reduced cell damage and inflammation after an exhaustive intense race. PMID:15306159

  5. Reanalysis of mGWAS results and in vitro validation show that lactate dehydrogenase interacts with branched-chain amino acid metabolism.

    PubMed

    Heemskerk, Mattijs M; van Harmelen, Vanessa Ja; van Dijk, Ko Willems; van Klinken, Jan Bert

    2016-01-01

    The assignment of causative genes to noncoding variants identified in genome-wide association studies (GWASs) is challenging. We show how combination of knowledge from gene and pathway databases and chromatin interaction data leads to reinterpretation of published quantitative trait loci for blood metabolites. We describe a previously unidentified link between the rs2403254 locus, which is associated with the ratio of 3-methyl-2-oxobutanoate and alpha-hydroxyisovalerate levels, and the distal LDHA gene. We confirmed that lactate dehydrogenase can catalyze the conversion between these metabolites in vitro, suggesting that it has a role in branched-chain amino acid metabolism. Examining datasets from the ENCODE project we found evidence that the locus and LDHA promoter physically interact, showing that LDHA expression is likely under control of distal regulatory elements. Importantly, this discovery demonstrates that bioinformatic workflows for data integration can have a vital role in the interpretation of GWAS results. PMID:26014429

  6. Purification of the fructose 1,6-bisphosphate-dependent lactate dehydrogenase from Streptococcus uberis and an investigation of its existence in different forms.

    PubMed Central

    Williams, R A; Andrews, P

    1986-01-01

    The fructose 1,6-bisphosphate [Fru(1,6)P2]-dependent lactate dehydrogenase in cells of Streptococcus uberis N.C.D.O. 2039 was purified by a procedure that included chromatography on DEAE-cellulose and Blue Sepharose CL-6B in phosphate buffers. The enzyme appeared to interact with Blue Sepharose through NADH-binding sites. The homogeneous enzyme had catalytic properties that were generally similar to those of other Fru(1,6)P2-dependent lactate dehydrogenases, and it had no catalytic activity in the absence of Fru(1,6)P2. Its existence in different forms, depending on conditions, was investigated by ultracentrifugation, analytical gel filtration and activity measurements. It consisted of subunits with Mr 35,900 +/- 500 and, in the presence of adequate concentrations of Fru(1,6)P2, phosphate or NADH, it existed as a tetramer, whereas when these ligands were in lower concentrations or absent, the subunits were in a concentration-dependent association-dissociation equilibrium. Dissociation occurred slowly and inactivated the enzyme, and although added ligands reversed the dissociation, the lost activity was at best only partly restored. An exception occurred when dissociation was caused by a decrease in temperature, in which case the lost activity was fully restored at the original temperature. The tetramer also lost activity at certain ligand concentrations without dissociating. The results together indicated the presence on the enzyme of two classes of binding site for both Fru(1,6)P2 and NADH, and the likelihood that phosphate bound at the same sites as Fru(1,6)P2. Two different ligands together were much more effective at preventing inactivation and dissociation than was expected from their effectiveness when present separately. It was concluded that tetrameric forms of the enzyme rather than the enzyme in association-dissociation equilibrium were involved in the regulation of its activity in vivo. PMID:3790089

  7. Major Role of NAD-Dependent Lactate Dehydrogenases in the Production of l-Lactic Acid with High Optical Purity by the Thermophile Bacillus coagulans

    PubMed Central

    Wang, Limin; Cai, Yumeng; Zhu, Lingfeng; Guo, Honglian

    2014-01-01

    Bacillus coagulans 2-6 is an excellent producer of optically pure l-lactic acid. However, little is known about the mechanism of synthesis of the highly optically pure l-lactic acid produced by this strain. Three enzymes responsible for lactic acid production—NAD-dependent l-lactate dehydrogenase (l-nLDH; encoded by ldhL), NAD-dependent d-lactate dehydrogenase (d-nLDH; encoded by ldhD), and glycolate oxidase (GOX)—were systematically investigated in order to study the relationship between these enzymes and the optical purity of lactic acid. Lactobacillus delbrueckii subsp. bulgaricus DSM 20081 (a d-lactic acid producer) and Lactobacillus plantarum subsp. plantarum DSM 20174 (a dl-lactic acid producer) were also examined in this study as comparative strains, in addition to B. coagulans. The specific activities of key enzymes for lactic acid production in the three strains were characterized in vivo and in vitro, and the levels of transcription of the ldhL, ldhD, and GOX genes during fermentation were also analyzed. The catalytic activities of l-nLDH and d-nLDH were different in l-, d-, and dl-lactic acid producers. Only l-nLDH activity was detected in B. coagulans 2-6 under native conditions, and the level of transcription of ldhL in B. coagulans 2-6 was much higher than that of ldhD or the GOX gene at all growth phases. However, for the two Lactobacillus strains used in this study, ldhD transcription levels were higher than those of ldhL. The high catalytic efficiency of l-nLDH toward pyruvate and the high transcription ratios of ldhL to ldhD and ldhL to the GOX gene provide the key explanations for the high optical purity of l-lactic acid produced by B. coagulans 2-6. PMID:25217009

  8. Effect of hyperoxia on the ultrastructural pathology of alveolar epithelium in relation to glutathione peroxidase, lactate dehydrogenase activities, and free radical production in rats, Rattus norvigicus.

    PubMed

    Bin-Jaliah, Ismaeel; Dallak, Mohammed; Haffor, Al-Said A

    2009-01-01

    Hyperoxia (HP) exposure inducts reactive oxygen species (ROS) in the lungs that may result in lung injury, including alveolar epithelial and endothelial cells. Lactate dehydrogenase (LDH) activity relates to glycolysis, whereas glutathione peroxidase (Gpx) activity relies on the pentose phosphate pathway (PPP). The purpose of this study was to examine early ROS-induced alveolar pathological changes in relation to the activity of glutathione peroxidase (GPx) and lactate dehydrogenase (LDH) activity. Twenty adult male rats, matched with age and body weight, were randomly assigned to two groups, control and experimental. The experimental group was exposed to hyperoxia for 24 h. Ultrastructure examination showed degenerated pneumocyte type I, containing swollen mitochondria associated with dilated rough endoplasmic reticulum, and was projecting into the alveolar lumen. Pneumocyte II showed mitochondria swelling and hyperplasia and was desquamated in structure, depleted in surfactant, and falling into the alveolar lumen. Pulmonary capillary showed distention without observed damage in the endothelial layer. Following HP, the average (+/-) free radical (FR) production increased significantly (p<.05) from the baseline control of 181.20+/-30.06 to 260.30+/-68.10 (Carr U) and average (+/-SD) GPx activity also increased significantly (p<.05) from the baseline control of 8178.30+/-2402.62 to 19,589.50+/-2392.44 (U/L), whereas average (+/-SD) LDH activity decreased significantly (p<.05) from baseline control of 194.11+/-75.52 to 42.68+/-11.41 (U/L), which demonstrated slowing down of glycolysis. Based on these results it can be concluded that exposure to high inspired oxygen inducted the buildup of mitochondria-driven ROS that was related to early injury in the alveolar epithelium without obvious endothelium injury. PMID:19479651

  9. [Leucine arylamidase, lactate dehydrogenase and alkaline phosphatase activity of the urine of normal subjects of infant age].

    PubMed

    Camerini, G; Castaldi, G; Menegatti, E

    1980-04-01

    Urinary activity of Leucine arylamidase, lactate dahydrogenase and Alkaline phosphatase in 14 healt subjects, ranging from 2 to 10 years are described. Some correlations between enzymatic activities, ratios enzymatic activities/creatininuria and enzymatic activities/dayly proteic clearance are investigated. PMID:7375016

  10. Highly stereoselective biosynthesis of (R)-α-hydroxy carboxylic acids through rationally re-designed mutation of d-lactate dehydrogenase

    PubMed Central

    Zheng, Zhaojuan; Sheng, Binbin; Gao, Chao; Zhang, Haiwei; Qin, Tong; Ma, Cuiqing; Xu, Ping

    2013-01-01

    An NAD-dependent d-lactate dehydrogenase (d-nLDH) of Lactobacillus bulgaricus ATCC 11842 was rationally re-designed for asymmetric reduction of a homologous series of α-keto carboxylic acids such as phenylpyruvic acid (PPA), α-ketobutyric acid, α-ketovaleric acid, β-hydroxypyruvate. Compared with wild-type d-nLDH, the Y52L mutant d-nLDH showed elevated activities toward unnatural substrates especially with large substitutes at C-3. By the biocatalysis combined with a formate dehydrogenase for in situ generation of NADH, the corresponding (R)-α-hydroxy carboxylic acids could be produced at high yields and highly optical purities. Taking the production of chiral (R)-phenyllactic acid (PLA) from PPA for example, 50 mM PPA was completely reduced to (R)-PLA in 90 min with a high yield of 99.0% and a highly optical purity (>99.9% e.e.) by the coupling system. The results presented in this work suggest a promising alternative for the production of chiral α-hydroxy carboxylic acids. PMID:24292439

  11. Expression, purification, crystallization and preliminary X-ray crystallographic analysis of L-lactate dehydrogenase and its H171C mutant from Bacillus subtilis

    SciTech Connect

    Zhang, Yanfeng; Gao, Xiaoli

    2012-08-31

    L-Lactate dehydrogenase (LDH) is an important enzyme involved in the last step of glycolysis that catalyzes the reversible conversion of pyruvate to L-lactate with the simultaneous oxidation of NADH to NAD{sup +}. In this study, wild-type LDH from Bacillus subtilis (BsLDH-WT) and the H171C mutant (BsLDH-H171C) were expressed in Escherichia coli and purified to near-homogeneity. BsLDH-WT was crystallized in the presence of fructose 1,6-bisphosphate (FBP) and NAD{sup +} and the crystal diffracted to 2.38 {angstrom} resolution. The crystal belonged to space group P3, with unit-cell parameters a = b = 171.04, c = 96.27 {angstrom}. BsLDH-H171C was also crystallized as the apoenzyme and in complex with NAD{sup +}, and data sets were collected to 2.20 and 2.49 {angstrom} resolution, respectively. Both BsLDH-H171C crystals belonged to space group P3, with unit-cell parameters a = b = 133.41, c = 99.34 {angstrom} and a = b = 133.43, c = 99.09 {angstrom}, respectively. Tetramers were observed in the asymmetric units of all three crystals.

  12. Oxamate-mediated inhibition of lactate dehydrogenase induces protective autophagy in gastric cancer cells: involvement of the Akt-mTOR signaling pathway.

    PubMed

    Zhao, Zhi; Han, Fanghai; Yang, Shibin; Wu, Jianhai; Zhan, Wenhua

    2015-03-01

    Cancer cells produce a substantial amount of energy through aerobic glycolysis even in the presence of adequate oxygen. Lactate dehydrogenase (LDH), a key regulator of glycolysis, reversibly catalyzes the conversion of pyruvate to lactate. Recently, oxamate, an inhibitor of LDH, has been shown to be a promising anticancer agent. However, the detailed mechanism remains largely unclear. In this study, we demonstrate that oxamate inhibits the viability of human gastric cancer cells in a dose- and time-dependent manner. In addition, treatment with oxamate induces protective autophagy in gastric cancer cells. Moreover, autophagy inhibited by chloroquine or Beclin 1 small interfering RNA (siRNA) enhances oxamate-induced apoptosis and proliferation inhibition. Further study has shown that oxamate treatment significantly augments reactive oxygen species (ROS) production. Furthermore, cells pretreated with N-acetyl cysteine (NAC), a ROS inhibitor, display significantly reduced ROS production and attenuated oxamate-induced autophagy. Finally, functional studies reveal that the Akt-mTOR signaling pathway, a major negative regulator of autophagy, is inhibited by oxamate. Together, our results provide new insights regarding the biological and anti-proliferative activities of oxamate against gastric cancer, and may offer a promising therapeutic strategy for gastric cancer. PMID:25524555

  13. Stable Suppression of Lactate Dehydrogenase Activity during Anoxia in the Foot Muscle of Littorina littorea and the Potential Role of Acetylation as a Novel Posttranslational Regulatory Mechanism

    PubMed Central

    Shahriari, Ali; Dawson, Neal J.; Bell, Ryan A. V.; Storey, Kenneth B.

    2013-01-01

    The intertidal marine snail, Littorina littorea, has evolved to withstand extended bouts of oxygen deprivation brought about by changing tides or other potentially harmful environmental conditions. Survival is dependent on a strong suppression of its metabolic rate and a drastic reorganization of its cellular biochemistry in order to maintain energy balance under fixed fuel reserves. Lactate dehydrogenase (LDH) is a crucial enzyme of anaerobic metabolism as it is typically responsible for the regeneration of NAD+, which allows for the continued functioning of glycolysis in the absence of oxygen. This study compared the kinetic and structural characteristics of the D-lactate specific LDH (E.C. 1.1.1.28) from foot muscle of aerobic control versus 24 h anoxia-exposed L. littorea. Anoxic LDH displayed a near 50% decrease in Vmax (pyruvate-reducing direction) as compared to control LDH. These kinetic differences suggest that there may be a stable modification and regulation of LDH during anoxia, and indeed, subsequent dot-blot analyses identified anoxic LDH as being significantly less acetylated than the corresponding control enzyme. Therefore, acetylation may be the regulatory mechanism that is responsible for the suppression of LDH activity during anoxia, which could allow for the production of alternative glycolytic end products that in turn would increase the ATP yield under fixed fuel reserves. PMID:24233354

  14. The lactate dehydrogenase--reduced nicotinamide--adenine dinucleotide--pyruvate complex. Kinetics of pyruvate binding and quenching of coeznyme fluorescence.

    PubMed

    Südi, J

    1974-04-01

    The stopped-flow kinetic studies described in this and the following paper (Südi, 1974) demonstrate that a Haldane-type description of the reversible lactate dehydrogenase reaction presents an experimentally feasible task. Combined results of these two papers yield numerical values for the six rate constants defined by the following equilibrium scheme, where E represents lactate dehydrogenase: [Formula: see text] The experiments were carried out at pH8.4 at a relatively low temperature (6.3 degrees C) with the pig heart enzyme. Identification of the above two intermediates and determination of the corresponding rate constants actually involve four series of independent observations in these studies, since (a) the reaction can be followed in both directions, and (b) both the u.v. absorption and the fluorescence of the coenzymes are altered in the reaction, and it is shown that these two spectral changes do not occur simultaneously. Kinetic observations made in the reverse direction are reported in this paper. It is demonstrated that the fluorescence of NADH can no longer be observed in the ternary complex E(NADH) (Pyr). Even though the oxidation-reduction reaction rapidly follows the formation of this complex, the numerical values of k(-4) (8.33x10(5)m(-1).s(-1)) and k(+4) (222s(-1)) are easily obtained from a directly observed second-order reaction step in which fluorescent but not u.v.-absorbing material is disappearing. U.v.-absorption measurements do not clearly resolve the subsequent oxidation-reduction step from the dissociation of lactate. It is shown that this must be due partly to the instrumental dead time, and partly to a low transient concentration of E(NAD+) (Lac) in the two-step sequential reaction in which the detectable disappearance of u.v.-absorbing material takes place. It is estimated that about one-tenth of the total change in u.v. absorption is due to a ;burst reaction' in which E(NAD+) (Lac) is produced, and this estimation yields, from k(obs.)=120s(-1), k(-2)=1200s(-1). PMID:4377095

  15. Differentiating inflamed and normal lungs by the apparent reaction rate constants of lactate dehydrogenase probed by hyperpolarized 13C labeled pyruvate

    PubMed Central

    Xu, He N.; Kadlececk, Stephen; Shaghaghi, Hoora; Zhao, Huaqing; Profka, Harilla; Pourfathi, Mehrdad; Rizi, Rahim

    2016-01-01

    Background Clinically translatable hyperpolarized (HP) 13C-NMR can probe in vivo enzymatic reactions, e.g., lactate dehydrogenase (LDH)-catalyzed reaction by injecting HP 13C-pyruvate into the subject, which is converted to 13C labeled lactate by the enzyme. Parameters such as 13C-lactate signals and lactate-to-pyruvate signal ratio are commonly used for analyzing the HP 13C-NMR data. However, the biochemical/biological meaning of these parameters remains either unclear or dependent on experimental settings. It is preferable to quantify the reaction rate constants with a clearer physical meaning. Here we report the extraction of the kinetic parameters of the LDH reaction from HP 13C-NMR data and investigate if they can be potential predictors of lung inflammation. Methods Male Sprague-Dawley rats (12 controls, 14 treated) were used. One dose of bleomycin (2.5 U/kg) was administered intratracheally to the treatment group. The lungs were removed, perfused, and observed by the HP-NMR technique, where a HyperSense dynamic nuclear polarization system was used to generate the HP 13C-pyruvate for injecting into the lungs. A 20 mm 1H/13C dual-tuned coil in a 9.4-T Varian vertical bore NMR spectrometer was employed to acquire the 13C spectral data every 1 s over a time period of 300 s using a non-selective, 15-degree radiofrequency pulse. The apparent rate constants of the LDH reaction and their ratio were quantified by applying ratiometric fitting analysis to the time series data of 13C labeled pyruvate and lactate. Results The apparent forward rate constant kp=(3.67±3.31)×10−4 s−1, reverse rate constant kl=(4.95±2.90)×10−2 s−1, rate constant ratio kp/kl=(7.53±5.75)×10−3 for the control lungs; kp=(11.71±4.35)×10−4 s−1, kl=(9.89±3.89)×10−2 s−1, and kp/kl=(12.39±4.18)×10−3 for the inflamed lungs at the 7th day post treatment. Wilcoxon rank-sum test showed that the medians of these kinetic parameters of the 7-day cohort were significantly larger than those of the control cohort (P<0.001, P=0.001, and P=0.019, respectively). The rate constants of individual lungs correlated significantly with the histology scores of neutrophils and organizing pneumonia foci but not macrophages. Both kp and kp/kl positively correlated with lactate labeling signals. No correlation was found between kl and lactate labeling signals. Conclusions The results indicate bleomycin-induced lung inflammation significantly increased both the forward and reverse reaction rate constants of LDH and their ratio at day-7 after bleomycin treatment. PMID:26981456

  16. Engineering a d-lactate dehydrogenase that can super-efficiently utilize NADPH and NADH as cofactors

    PubMed Central

    Meng, Hengkai; Liu, Pi; Sun, Hongbing; Cai, Zhen; Zhou, Jie; Lin, Jianping; Li, Yin

    2016-01-01

    Engineering the cofactor specificity of a natural enzyme often results in a significant decrease in its activity on original cofactor. Here we report that a NADH-dependent dehydrogenase (d-LDH) from Lactobacillus delbrueckii 11842 can be rationally engineered to efficiently use both NADH and NADPH as cofactors. Point mutations on three amino acids (D176S, I177R, F178T) predicted by computational analysis resulted in a modified enzyme designated as d-LDH*. The Kcat/Km of the purified d-LDH* on NADPH increased approximately 184-fold while the Kcat/Km on NADH also significantly increased, showing for the first time that a rationally engineered d-LDH could exhibit comparable activity on both NADPH and NADH. Further kinetic analysis revealed that the enhanced affinity with NADH or NADPH and the significant increased Kcat of d-LDH* resulted in the significant increase of d-LDH* activity on both NADPH and NADH. This study thus demonstrated that the cofactor specificity of dehydrogenase can be broadened by using targeted engineering approach, and the engineered enzyme can efficiently function in NADH-rich, or NADPH-rich, or NADH and NADPH-rich environment. PMID:27109778

  17. The intrinsically disordered protein LEA7 from Arabidopsis thaliana protects the isolated enzyme lactate dehydrogenase and enzymes in a soluble leaf proteome during freezing and drying.

    PubMed

    Popova, Antoaneta V; Rausch, Saskia; Hundertmark, Michaela; Gibon, Yves; Hincha, Dirk K

    2015-10-01

    The accumulation of Late Embryogenesis Abundant (LEA) proteins in plants is associated with tolerance against stresses such as freezing and desiccation. Two main functions have been attributed to LEA proteins: membrane stabilization and enzyme protection. We have hypothesized previously that LEA7 from Arabidopsis thaliana may stabilize membranes because it interacts with liposomes in the dry state. Here we show that LEA7, contrary to this expectation, did not stabilize liposomes during drying and rehydration. Instead, it partially preserved the activity of the enzyme lactate dehydrogenase (LDH) during drying and freezing. Fourier-transform infrared (FTIR) spectroscopy showed no evidence of aggregation of LDH in the dry or rehydrated state under conditions that lead to complete loss of activity. To approximate the complex influence of intracellular conditions on the protective effects of a LEA protein in a convenient in-vitro assay, we measured the activity of two Arabidopsis enzymes (glucose-6-P dehydrogenase and ADP-glucose pyrophosphorylase) in total soluble leaf protein extract (Arabidopsis soluble proteome, ASP) after drying and rehydration or freezing and thawing. LEA7 partially preserved the activity of both enzymes under these conditions, suggesting its role as an enzyme protectant in vivo. Further FTIR analyses indicated the partial reversibility of protein aggregation in the dry ASP during rehydration. Similarly, aggregation in the dry ASP was strongly reduced by LEA7. In addition, mixtures of LEA7 with sucrose or verbascose reduced aggregation more than the single additives, presumably through the effects of the protein on the H-bonding network of the sugar glasses. PMID:25988244

  18. Interdependence of coenzyme-induced conformational work and binding potential in yeast alcohol and porcine heart lactate dehydrogenases: a hydrogen-deuterium exchange study

    SciTech Connect

    De Weck, Z.; Pande, J.; Kaegi, J.H.R.

    1987-07-28

    Binding of NAD coenzymes to yeast alcohol dehydrogenase (YADH) and porcine heart lactate dehydrogenase (PHLDH) was studied by hydrogen-deuterium exchange with the infrared technique. Conformational changes in the enzymes specific to the coenzymes and their fragments were observed, and the pH dependence of the exchange reaction shows that it conforms to the EX-2 scheme. In both YADH and PHLDH the magnitude of the conformational change as measured by exchange retardation is considerably larger for the NAD/sup +/ than for NADH. Studies with coenzyme fragments like ADP-ribose, ADP, and AMP also highlight the lack of rigorous correlation between structural features such as charge and size and their influence on exchange behavior. Ternary complexes such as YADH-NAD/sup +/-pyrazole, PHLDH-NAD/sup +/-oxalate, and PHLDH-NADH-oxamate, which mimic the transition state, have a significantly more pronounced effect on exchange rates than the corresponding binary complexes. The outstanding feature of this study is the demonstration that in the binary enzyme-coenzyme complexes the more loosely bound NAD/sup +/ is more effective in retarding exchange than the more firmly bound NADH. These differences are attributed to the unequal structural constraints exerted by the two coenzymes upon the enzymes, which translate to unequal expenditure of transconformational work in the formation of the two complexes. The opposing variation in the free energy of binding and the transconformational work expended can be viewed as an unequal partitioning of the net free energy gain resulting from the protein-ligand interaction into a binding term and that required for conformational change.

  19. Insulin, CCAAT/Enhancer-Binding Proteins and Lactate Regulate the Human 11β-Hydroxysteroid Dehydrogenase Type 2 Gene Expression in Colon Cancer Cell Lines

    PubMed Central

    Alikhani-Koupaei, Rasoul; Ignatova, Irena D.; Guettinger, Andreas; Frey, Felix J.; Frey, Brigitte M.

    2014-01-01

    11β-Hydroxysteroid dehydrogenases (11beta-HSD) modulate mineralocorticoid receptor transactivation by glucocorticoids and regulate access to the glucocorticoid receptor. The isozyme 11beta-HSD2 is selectively expressed in mineralocorticoid target tissues and its activity is reduced in various disease states with abnormal sodium retention and hypertension, including the apparent mineralocorticoid excess. As 50% of patients with essential hypertension are insulin resistant and hyperinsulinemic, we hypothesized that insulin downregulates the 11beta-HSD2 activity. In the present study we show that insulin reduced the 11beta-HSD2 activity in cancer colon cell lines (HCT116, SW620 and HT-29) at the transcriptional level, in a time and dose dependent manner. The downregulation was reversible and required new protein synthesis. Pathway analysis using mRNA profiling revealed that insulin treatment modified the expression of the transcription factor family C/EBPs (CCAAT/enhancer-binding proteins) but also of glycolysis related enzymes. Western blot and real time PCR confirmed an upregulation of C/EBP beta isoforms (LAP and LIP) with a more pronounced increase in the inhibitory isoform LIP. EMSA and reporter gene assays demonstrated the role of C/EBP beta isoforms in HSD11B2 gene expression regulation. In addition, secretion of lactate, a byproduct of glycolysis, was shown to mediate insulin-dependent HSD11B2 downregulation. In summary, we demonstrate that insulin downregulates HSD11B2 through increased LIP expression and augmented lactate secretion. Such mechanisms are of interest and potential significance for sodium reabsorption in the colon. PMID:25133511

  20. Improved Production of Homo-d-Lactic Acid via Xylose Fermentation by Introduction of Xylose Assimilation Genes and Redirection of the Phosphoketolase Pathway to the Pentose Phosphate Pathway in l-Lactate Dehydrogenase Gene-Deficient Lactobacillus plantarum▿

    PubMed Central

    Okano, Kenji; Yoshida, Shogo; Yamada, Ryosuke; Tanaka, Tsutomu; Ogino, Chiaki; Fukuda, Hideki; Kondo, Akihiko

    2009-01-01

    The production of optically pure d-lactic acid via xylose fermentation was achieved by using a Lactobacillus plantarum NCIMB 8826 strain whose l-lactate dehydrogenase gene was deficient and whose phosphoketolase genes were replaced with a heterologous transketolase gene. After 60 h of fermentation, 41.2 g/liter of d-lactic acid was produced from 50 g/liter of xylose. PMID:19820147

  1. Inhibition of Growth by Combined Treatment with Inhibitors of Lactate Dehydrogenase and either Phenformin or Inhibitors of 6-Phosphofructo-2-kinase/Fructose-2,6-bisphosphatase 3.

    PubMed

    Lea, Michael A; Guzman, Yolanda; Desbordes, Charles

    2016-04-01

    Enhanced glycolysis in cancer cells presents a target for chemotherapy. Previous studies have indicated that proliferation of cancer cells can be inhibited by treatment with phenformin and with an inhibitor of 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase 3 (PFKFB) namely 3-(3-pyridinyl)-1-(4-pyridinyl)-2-propen-1-one (3PO). In the present work, the action of two inhibitors that are effective at lower concentrations than 3PO, namely 1-(3-pyridinyl)-3-(2-quinolinyl)-2-propen-1-one (PQP) and 1-(4-pyridinyl)-3-(2-quinolinyl)-2-propen-1-one (PFK15) were investigated. The inhibitors of lactate dehydrogenase (LDHA) studied in order of half-maximal inhibitory concentrations were methyl 1-hydroxy-6-phenyl-4-(trifluoromethyl)-1H-indole-2-carboxylate (NHI-2) < isosafrole < oxamate. In colonic and bladder cancer cells, additive growth inhibitory effects were seen with the LDHA inhibitors, of which NHI-2 was effective at the lowest concentrations. Growth inhibition was generally greater with PFK15 than with PQP. The increased acidification of the culture medium and glucose uptake caused by phenformin was blocked by combined treatment with PFKFB3 or LDHA inhibitors. The results suggest that combined treatment with phenformin and inhibitors of glycolysis can cause additive inhibition of cell proliferation and may mitigate lactic acidosis caused by phenformin when used as a single agent. PMID:27069123

  2. Identification of a novel operon in Lactococcus lactis encoding three enzymes for lactic acid synthesis: phosphofructokinase, pyruvate kinase, and lactate dehydrogenase.

    PubMed Central

    Llanos, R M; Harris, C J; Hillier, A J; Davidson, B E

    1993-01-01

    The discovery of a novel multicistronic operon that encodes phosphofructokinase, pyruvate kinase, and lactate dehydrogenase in the lactic acid bacterium Lactococcus lactis is reported. The three genes in the operon, designated pfk, pyk, and ldh, contain 340, 502, and 325 codons, respectively. The intergenic distances are 87 bp between pfk and pyk and 117 bp between pyk and ldh. Plasmids containing pfk and pyk conferred phosphofructokinase and pyruvate kinase activity, respectively, on their host. The identity of ldh was established previously by the same approach (R. M. Llanos, A. J. Hillier, and B. E. Davidson, J. Bacteriol. 174:6956-6964, 1992). Each of the genes is preceded by a potential ribosome binding site. The operon is expressed in a 4.1-kb transcript. The 5' end of the transcript was determined to be a G nucleotide positioned 81 bp upstream from the pfk start codon. The pattern of codon usage within the operon is highly biased, with 11 unused amino acid codons. This degree of bias suggests that the operon is highly expressed. The three proteins encoded on the operon are key enzymes in the Embden-Meyerhoff pathway, the central pathway of energy production and lactic acid synthesis in L. lactis. For this reason, we have called the operon the las (lactic acid synthesis) operon. Images PMID:8478320

  3. Incompatibility of silver nanoparticles with lactate dehydrogenase leakage assay for cellular viability test is attributed to protein binding and reactive oxygen species generation.

    PubMed

    Oh, Seok-Jeong; Kim, Hwa; Liu, Yingqiu; Han, Hyo-Kyung; Kwon, Kyenghee; Chang, Kyung-Hwa; Park, Kwangsik; Kim, Younghun; Shim, Kyuhwan; An, Seong Soo A; Lee, Moo-Yeol

    2014-03-21

    A growing number of studies report that conventional cytotoxicity assays are incompatible with certain nanoparticles (NPs) due to artifacts caused by the distinctive characteristics of NPs. Lactate dehydrogenase (LDH) leakage assays have inadequately detected cytotoxicity of silver nanoparticles (AgNPs), leading to research into the underlying mechanism. When ECV304 endothelial-like umbilical cells were treated with citrate-capped AgNPs (cAgNPs) or bare AgNPs (bAgNPs), the plasma membrane was disrupted, but the LDH leakage assay failed to detect cytotoxicity, indicating interference with the assay by AgNPs. Both cAgNPs and bAgNPs inactivated LDH directly when treated to cell lysate as expected. AgNPs adsorbed LDH and thus LDH, together with AgNPs, was removed from assay reactants during sample preparation, with a resultant underestimation of LDH leakage from cells. cAgNPs, but not bAgNPs, generated reactive oxygen species (ROS), which were successfully scavenged by N-acetylcysteine or ascorbic acid. LDH inhibition by cAgNPs could be restored partially by simultaneous treatment with those antioxidants, suggesting the contribution of ROS to LDH inactivation. Additionally, the composition of the protein corona surrounding AgNPs was identified employing liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis. In sum, the LDH leakage assay, a conventional cell viability test method, should be employed with caution when assessing cytotoxicity of AgNPs. PMID:24463055

  4. Baseline Serum Lactate Dehydrogenase Levels for Patients Treated With Intensity-Modulated Radiotherapy for Nasopharyngeal Carcinoma: A Predictor of Poor Prognosis and Subsequent Liver Metastasis

    SciTech Connect

    Zhou Guanqun; Tang Linglong; Mao Yanping; Chen Lei; Li Wenfei; Sun Ying; Liu Lizhi; Li Li; Lin Aihua; Ma Jun

    2012-03-01

    Purpose: To evaluate the prognostic value of baseline serum lactate dehydrogenase (LDH) levels in patients with nasopharyngeal carcinoma (NPC) treated with intensity-modulated radiotherapy (IMRT). Methods and Materials: Cases of NPC (n = 465) that involved treatment with IMRT with or without chemotherapy were retrospectively analyzed. Results: The mean ({+-}SD) and median baseline serum LDH levels for this cohort were 172.77 {+-} 2.28 and 164.00 IU/L, respectively. Levels of LDH were significantly elevated in patients with locoregionally advanced disease (p = 0.016). Elevated LDH levels were identified as a prognostic factor for rates of overall survival (OS), disease-free survival (DFS), and distant metastasis-free survival (DMFS), with p values <0.001 in the univariate analysis and p < 0.001, p = 0.004, and p = 0.003, respectively, in the multivariate analysis. Correspondingly, the prognostic impact of patient LDH levels was found to be statistically significant for rates of OS, DFS, and DMFS (p = 0.028, 0.024, and 0.020, respectively). For patients who experienced subsequent liver failure after treatment, markedly higher pretreatment serum LDH levels were detected compared with patients experiencing distant metastasis events at other sites (p = 0.032). Conclusions: Elevated baseline LDH levels are associated with clinically advanced disease and are a poor prognosticator for OS, DFS, and DMFS for NPC patients. These results suggest that elevated serum levels of LDH should be considered when evaluating treatment options.

  5. A Streamlined, Automated Protocol for the Production of Milligram Quantities of Untagged Recombinant Rat Lactate Dehydrogenase A Using ÄKTAxpressTM

    PubMed Central

    Nowicki, Matthew W.; Blackburn, Elizabeth A.; McNae, Iain W.; Wear, Martin A.

    2015-01-01

    We developed an efficient, automated 2-step purification protocol for the production of milligram quantities of untagged recombinant rat lactate dehydrogenase A (rLDHA) from E. coli, using the ÄKTAxpress™ chromatography system. Cation exchange followed by size exclusion results in average final purity in excess of 93% and yields ~ 14 milligrams per 50 ml of original cell culture in EnPresso B media, in under 8 hrs, including all primary sample processing and column equilibration steps. The protein is highly active and coherent biophysically and a viable alternative to the more problematic human homolog for structural and ligand-binding studies; an apo structure of untagged rLDHA was solved to a resolution 2.29 Å (PDB ID 5ES3). Our automated methodology uses generic commercially available pre-packed columns and simple buffers, and represents a robust standard method for the production of milligram amounts of untagged rLDHA, facilitating a novel fragment screening approach for new inhibitors. PMID:26717415

  6. Rationally re-designed mutation of NAD-independent l-lactate dehydrogenase: high optical resolution of racemic mandelic acid by the engineered Escherichia coli

    PubMed Central

    2012-01-01

    Background NAD-independent l-lactate dehydrogenase (l-iLDH) from Pseudomonas stutzeri SDM can potentially be used for the kinetic resolution of small aliphatic 2-hydroxycarboxylic acids. However, this enzyme showed rather low activity towards aromatic 2-hydroxycarboxylic acids. Results Val-108 of l-iLDH was changed to Ala by rationally site-directed mutagenesis. The l-iLDH mutant exhibited much higher activity than wide-type l-iLDH towards l-mandelate, an aromatic 2-hydroxycarboxylic acid. Using the engineered Escherichia coli expressing the mutant l-iLDH as a biocatalyst, 40 g·L-1 of dl-mandelic acid was converted to 20.1 g·L-1 of d-mandelic acid (enantiomeric purity higher than 99.5%) and 19.3 g·L-1 of benzoylformic acid. Conclusions A new biocatalyst with high catalytic efficiency toward an unnatural substrate was constructed by rationally re-design mutagenesis. Two building block intermediates (optically pure d-mandelic acid and benzoylformic acid) were efficiently produced by the one-pot biotransformation system. PMID:23176608

  7. A comparison of the primary structures of lactate dehydrogenase isozymes M4 from giant panda, red panda, black bear and dog.

    PubMed

    Liang, S P; Zhang, L X

    1987-03-01

    Lactate dehydrogenase isozymes M4 have been isolated and purified from red panda (Ailurus fulgens), black bear (Selenarctos thibetanus) and dog (Canis familiars) by affinity chromatography and compared with that from giant panda (Ailuropoda melanoleuca). Experimental results have shown that the N-termini, C-termini and the molecular weights of LDH-M subunits of red panda, black bear and dog are the same as those of the LDH-M subunit of giant panda. Analysis and comparison of HPLC peptide maps from the tryptic digests of the isozymes of red panda, black bear and dog have shown that most of their peptide fragments had the same retention time and amino acid composition as the corresponding peptide fragments from giant panda. Fragments with different retention times and/or amino acid compositions were sequenced. Careful examination of those variant amino acid residues demonstrated clearly that the primary structure of giant panda LDH-M subunit is unique and it appears that the giant panda might be classified as an independent family. PMID:3629217

  8. Dynamics of a Lactate Dehydrogenase Polymorphism in the Wood Louse PORCELLIO SCABER Latr.: Evidence for Partial Assortative Mating and Heterosis in Natural Populations

    PubMed Central

    Sassaman, Clay

    1978-01-01

    Electrophoretic separation of lactate dehydrogenase (LDH) of Porcellio scaber from 14 natural populations in California, and one each in Oregon, Delaware and Massachusetts, indicates a biallelic polymorphism. Phenotypes are recovered from laboratory matings of virgin females in frequencies agreeing with simple Mendelian inheritance, and the frequency distributions of phenotypes in natural populations are typically in agreement with the appropriate Hardy-Weinberg distributions for these same populations. The same allele predominates in all natural populations examined. Temporal stability within populations suggests that the polymorphism is at, or near, equilibrium. The spatial distribution of allele frequencies, however, is apparently mosaic. Abrupt discontinuities in gene frequency over short distances (50 m to 1 km) suggest that interpopulation migration is insufficient to swamp local differences in gene frequency. Analysis of the transmission dynamics of the polymorphism in natural populations using mother-offspring genotype comparisons suggests that the allelic frequencies of transmitted male gametes are not independent of female genotype. Specifically, the observed mating scheme in natural populations appears to be partially assortative. Comparisons of progeny genotype distributions with yearling (or adult) genotype distributions from the same populations indicate a superior post-partum viability of heterozygous individuals relative to homozygotes. The distortion of progeny genotypic distributions created by assortment is thus apparently counteracted by subsequent heterosis. PMID:640378

  9. Evaluation of Milk Trace Elements, Lactate Dehydrogenase, Alkaline Phosphatase and Aspartate Aminotransferase Activity of Subclinical Mastitis as and Indicator of Subclinical Mastitis in Riverine Buffalo (Bubalus bubalis)

    PubMed Central

    Guha, Anirban; Gera, Sandeep; Sharma, Anshu

    2012-01-01

    Mastitis is a highly morbid disease that requires detection at the subclinical stage. Tropical countries like India mainly depend on milch buffaloes for milk. The present study was conducted to investigate whether the trace minerals viz. copper (Cu), iron (Fe), zinc (Zn), cobalt (Co) and manganese (Mn) and enzyme activity of lactate dehydrogenase (LDH), alkaline phosphatase (ALP) and aspartate aminotransferase (AST) in riverine buffalo milk can be used as an indicator of subclinical mastitis (SCM) with the aim of developing suitable diagnostic kit for SCM. Trace elements and enzyme activity in milk were estimated with Atomic absorption Spectrophotometer, GBC 932 plus and biochemical methods, respectively. Somatic cell count (SCC) was done microscopically. The cultural examination revealed Gram positive bacteria as the most prevalent etiological agent. A statistically significant (p<0.01) increase in SCC, Fe, Zn, Co and LDH occurred in SCM milk containing gram positive bacterial agents only. ALP was found to be elevated in milk infected by both gram positive and negative bacteria. The percent sensitivity, specificity and accuracy, predictive values and likelihood ratios were calculated taking bacterial culture examination and SCC≥2×105 cells/ml of milk as the benchmark. Only ALP and Zn, the former being superior, were found to be suitable for diagnosis of SCM irrespective of etiological agents. LDH, Co and Fe can be introduced in the screening programs where Gram positive bacteria are omnipresent. It is recommended that both ALP and Zn be measured together in milk to diagnose buffalo SCM, irrespective of etiology. PMID:25049573

  10. Decreased hematocrit-to-viscosity ratio and increased lactate dehydrogenase level in patients with sickle cell anemia and recurrent leg ulcers.

    PubMed

    Connes, Philippe; Lamarre, Yann; Hardy-Dessources, Marie-Dominique; Lemonne, Nathalie; Waltz, Xavier; Mougenel, Danièle; Mukisi-Mukaza, Martin; Lalanne-Mistrih, Marie-Laure; Tarer, Vanessa; Tressières, Benoit; Etienne-Julan, Maryse; Romana, Marc

    2013-01-01

    Leg ulcer is a disabling complication in patients with sickle cell anemia (SCA) but the exact pathophysiological mechanisms are unknown. The aim of this study was to identify the hematological and hemorheological alterations associated with recurrent leg ulcers. Sixty-two SCA patients who never experienced leg ulcers (ULC-) and 13 SCA patients with a positive history of recurrent leg ulcers (ULC+)--with no leg ulcers at the time of the study--were recruited. All patients were in steady state condition. Blood was sampled to perform hematological, biochemical (hemolytic markers) and hemorheological analyses (blood viscosity, red blood cell deformability and aggregation properties). The hematocrit-to-viscosity ratio (HVR), which reflects the red blood cell oxygen transport efficiency, was calculated for each subject. Patients from the ULC+ group were older than patients from the ULC- group. Anemia (red blood cell count, hematocrit and hemoglobin levels) was more pronounced in the ULC+ group. Lactate dehydrogenase level was higher in the ULC+ group than in the ULC- group. Neither blood viscosity, nor RBC aggregation properties differed between the two groups. HVR was lower and RBC deformability tended to be reduced in the ULC+ group. Our study confirmed increased hemolytic rate and anemia in SCA patients with leg ulcers recurrence. Furthermore, our data suggest that although systemic blood viscosity is not a major factor involved in the pathophysiology of this complication, decreased red blood cell oxygen transport efficiency (i.e., low hematocrit/viscosity ratio) may play a role. PMID:24223994

  11. Decreased Hematocrit-To-Viscosity Ratio and Increased Lactate Dehydrogenase Level in Patients with Sickle Cell Anemia and Recurrent Leg Ulcers

    PubMed Central

    Connes, Philippe; Lamarre, Yann; Hardy-Dessources, Marie-Dominique; Lemonne, Nathalie; Waltz, Xavier; Mougenel, Danièle; Mukisi-Mukaza, Martin; Lalanne-Mistrih, Marie-Laure; Tarer, Vanessa; Tressières, Benoit; Etienne-Julan, Maryse; Romana, Marc

    2013-01-01

    Leg ulcer is a disabling complication in patients with sickle cell anemia (SCA) but the exact pathophysiological mechanisms are unknown. The aim of this study was to identify the hematological and hemorheological alterations associated with recurrent leg ulcers. Sixty-two SCA patients who never experienced leg ulcers (ULC-) and 13 SCA patients with a positive history of recurrent leg ulcers (ULC+) - but with no leg ulcers at the time of the study – were recruited. All patients were in steady state condition. Blood was sampled to perform hematological, biochemical (hemolytic markers) and hemorheological analyses (blood viscosity, red blood cell deformability and aggregation properties). The hematocrit-to-viscosity ratio (HVR), which reflects the red blood cell oxygen transport efficiency, was calculated for each subject. Patients from the ULC+ group were older than patients from the ULC- group. Anemia (red blood cell count, hematocrit and hemoglobin levels) was more pronounced in the ULC+ group. Lactate dehydrogenase level was higher in the ULC+ group than in the ULC- group. Neither blood viscosity, nor RBC aggregation properties differed between the two groups. HVR was lower and RBC deformability tended to be reduced in the ULC+ group. Our study confirmed increased hemolytic rate and anemia in SCA patients with leg ulcers recurrence. Furthermore, our data suggest that although systemic blood viscosity is not a major factor involved in the pathophysiology of this complication, decreased red blood cell oxygen transport efficiency (i.e., low hematocrit/viscosity ratio) may play a role. PMID:24223994

  12. Engineered topographic determinants with alpha beta, beta alpha beta, and beta alpha beta alpha topologies show high affinity binding to native protein antigen (lactate dehydrogenase-C4).

    PubMed

    Kobs-Conrad, S; Lee, H; DiGeorge, A M; Kaumaya, P T

    1993-12-01

    The use of peptides has attracted much interest in the development of synthetic vaccines. Although our current understanding of peptide antigens as immunogens has been greatly advanced recently, there still remain many obstacles. The B cell response elicited by a peptide antigen is governed by a number of poorly understood events such as epitope structure, T cell dependency and major histocompatibility complex restriction, adjuvancy, route of immunization, and immunogen stability. In this paper, we extend our previous studies on the problem of the topographical nature of antigenic sites on native protein antigens, in terms of how much molecular mimicry must be maintained in an antigenic determinant for the induction of high affinity antibodies specific for native protein. We show here that an antigenic epitope from the model contraceptive vaccine candidate lactate dehydrogenase (LDH-C4) can be rationally engineered into a highly structured conformation that mimics the corresponding site in the native three-dimensional protein. Our strategy is based on the selection of an antigenic segment which exhibits certain secondary structural properties and by design principles is fixed in three dimensions by appropriate grafting onto a supersecondary structural motif such as alpha beta, beta alpha beta, or beta alpha beta alpha. The biophysical data are consistent with the proposed secondary structures, and antibodies raised to the various construct show high affinity for the native protein. These studies lend further credence to the conformational nature of peptide epitopes and provide a basis for the rational design of peptide vaccines. PMID:8244959

  13. A reagentless amperometric electrode based on carbon paste, chemically modified with D-lactate dehydrogenase, NAD(+), and mediator containing polymer for D-lactic acid analysis. I. Construction, composition, and characterization.

    PubMed

    Shu, H C; Mattiasson, B; Persson, B; Nagy, G; Gorton, L; Sahni, S; Geng, L; Boguslavsky, L; Skotheim, T

    1995-05-01

    A reagentless carbon paste electrode was designed for D-lactic acid analysis in a flow injection system for the monitoring of the production of D-lactate in a batch fermentation. D-Lactate dehydrogenase, nicotinamide adenine dinucleotide (NAD(+)), a synthetic redox polymer containing covalently attached toluidine blue O as mediator, graphite powder, and paraffin oil were used for the construction of the modified carbon paste electrode. D-Lactate selectivity was indicated by insignificant responses from a variety of possible interfernces including L-lactate. The electrodes gave a linear response in the range between 0.05 and 5 mM D-lactate, with a detecting limit of 30 muM, allowing a sample throughput of 20 h(-1). Preliminary investigations were made by covering the electrode surface with electropolymerized membranes. Satisfactory stability was observed, indicated by a reproducibility of 3.3% relative standard deviation (RSD, n = 31), with a non-membrane-covered electrode for the analysis of D-lactate in fermentation broth. A long-term stability (230 broth samples) was proven, suggesting the electrodes to have a good potential for use in on-line monitoring of fermentation processes. (c) 1995 John Wiley & Sons, Inc. PMID:18623311

  14. Testis-Specific Lactate Dehydrogenase (LDH-C4) in Skeletal Muscle Enhances a Pika’s Sprint-Running Capacity in Hypoxic Environment

    PubMed Central

    Wang, Yang; Wei, Lian; Wei, Dengbang; Li, Xiao; Xu, Lina; Wei, Linna

    2015-01-01

    LDH-C4 is a lactate dehydrogenase that catalyzes the conversion of pyruvate to lactate. In mammals, ldh-c was originally thought to be expressed only in testis and spermatozoa. Plateau pika (Ochotona curzoniae), which belongs to the genus Ochotona of the Ochotonidea family, is a hypoxia tolerant mammal living 3000–5000 m above sea level on the Qinghai-Tibet Plateau, an environment which is strongly hypoxic. Ldh-c is expressed not only in testis and sperm but also in somatic tissues of plateau pika. In this study, the effects of N-propyl oxamate and N-isopropyl oxamate on LDH isozyme kinetics were compared to screens for a selective inhibitor of LDH-C4. To reveal the role and physiological mechanism of LDH-C4 in skeletal muscle of plateau pika, we investigated the effect of N-isopropyl oxamate on the pika exercise tolerance as well as the physiological mechanism. Our results show that Ki of N-propyl oxamate and N-isopropyl oxamate for LDH-A4, LDH-B4, and LDH-C4 were 0.094 mmol/L and 0.462 mmol/L, 0.119 mmol/L and 0.248 mmol/L, and 0.015 mmol/L and 0.013 mmol/L, respectively. N-isopropyl oxamate is a powerful selective inhibitor of plateau pika LDH-C4. In our exercise tolerance experiment, groups treated with inhibitors had significantly lower swimming times than the uninhibited control group. The inhibition rates of LDH, LD, and ATP were 37.12%, 66.27%, and 32.42%, respectively. Our results suggested that ldh-c is expressed in the skeletal muscle of plateau pika, and at least 32.42% of ATP in the skeletal muscle is catalyzed by LDH-C4 by anaerobic glycolysis. This suggests that pika has reduced dependence on oxygen and enhanced adaptation to hypoxic environment due to increased anaerobic glycolysis by LDH-C4 in skeletal muscle. LDH-C4 in plateau pika plays the crucial role in anaerobic glycolysis and generates ATP rapidly since this is the role of LDH-A4 in most species on plain land, which provide evidence that the native humans and animals in Qinghai-Tibet plateau can adapt to the hypoxia environment. PMID:26262630

  15. Molecular Characterization of CcpA and Involvement of This Protein in Transcriptional Regulation of Lactate Dehydrogenase and Pyruvate Formate-Lyase in the Ruminal Bacterium Streptococcus bovis

    PubMed Central

    Asanuma, Narito; Yoshii, Takahiro; Hino, Tsuneo

    2004-01-01

    A ccpA gene that encodes global catabolite control protein A (CcpA) in Streptococcus bovis was identified and characterized, and the involvement of CcpA in transcriptional control of a gene (ldh) encoding lactate dehydrogenase (LDH) and a gene (pfl) encoding pyruvate formate-lyase (PFL) was examined. The ccpA gene was shown to be transcribed as a monocistronic operon. A catabolite-responsive element (cre) was found in the promoter region of ccpA, suggesting that ccpA transcription in S. bovis is autogenously regulated. CcpA required HPr that was phosphorylated at the serine residue at position 46 (HPr-[Ser-P]) for binding to the cre site, but glucose 6-phosphate, fructose 1,6-bisphosphate, and NADP had no effect on binding. Diauxic growth was observed when S. bovis was grown in a medium containing glucose and lactose, but it disappeared when ccpA was disrupted, which indicates that CcpA is involved in catabolite repression in S. bovis. The level of ccpA mRNA was higher when cells were grown on glucose than when they were grown on lactose, which was in line with the level of ldh mRNA. When cells were grown on glucose, the ldh mRNA level was lower but the pfl mRNA level was higher in a ccpA-disrupted mutant than in the parent strain, which suggests that ldh transcription is enhanced and pfl transcription is suppressed by CcpA. The ccpA-disrupted mutant produced less lactate and more formate than the parent, probably because the mutant had reduced LDH activity and elevated PFL activity. In the upper region of both ldh and pfl, a cre-like sequence was found, suggesting that the complex consisting of CcpA and HPr-[Ser-P] binds to the possible cre sites. Thus, CcpA appears to be involved in the global regulation of sugar utilization in S. bovis. PMID:15345406

  16. [The expression of the sperm-specific lactate dehydrogenase gene Ldh-c in plateau pika (Ochotona curzoniae) cardiac muscle and its effect on the anaerobic glycolysis].

    PubMed

    Li, Xiao; Wei, Lian; Wang, Yang; Xu, Li-Na; Wei, Lin-Na; Wei, Deng-Bang

    2015-06-25

    The plateau pika (Ochotona curzoniae) has a strong adaptability to hypoxic plateau environment. We found that the sperm-specific lactate dehydrogenase (LDH-C4) gene Ldh-c expressed in plateau pika cardiac muscle. In order to shed light on the effect of LDH-C4 on the anaerobic glycolysis in plateau pika cardiac muscle, 20 pikas were randomly divided into the inhibitor group and the control group, and the sample size of each group was 10. The pikas of inhibitor group were injected with 1 mL 1 mol/L N-isopropyl oxamate, a specific LDH-C4 inhibitor, in biceps femoris muscle of hind legs, each leg with 500 μL. The pikas of control group were injected with the same volume of normal saline (0.9% NaCl). The mRNA and protein expression levels of Ldh-c gene in plateau pika cardiac muscle were determined by real-time PCR and Western blot. The activities of LDH, and the contents of lactate (LD) and ATP in cardiac muscle were compared between the inhibitor group and the control group. The results showed that 1) the expression levels of Ldh-c mRNA and protein were 0.47 ± 0.06 and 0.68 ± 0.08, respectively; 2) 30 min after injection of 1 mL 1 mol/L N-isopropyl oxamate in biceps femoris muscle, the concentration of N-isopropyl oxamate in blood was 0.08 mmol/L; 3) in cardiac muscle of the inhibitor group and the control group, the LDH activities were (6.18 ± 0.48) U/mg and (9.08 ± 0.58) U/mg, the contents of LD were (0.21 ± 0.03) mmol/g and (0.26 ± 0.04) mmol/g, and the contents of ATP were (4.40 ± 0.69) nmol/mg and (6.18 ± 0.73) nmol/mg (P < 0.01); 5) the inhibition rates of N-isopropyl oxamate to LDH, LD and ATP were 31.98%, 20.90% and 28.70%, respectively. The results suggest that Ldh-c expresses in cardiac muscle of plateau pika, and the pika cardiac muscle may get at least 28% ATP for its activities by LDH-C4 catalyzed anaerobic glycolysis, which reduces the dependence on oxygen and enhances the adaptation to the hypoxic environments. PMID:26109304

  17. Testis-Specific Lactate Dehydrogenase (LDH-C4) in Skeletal Muscle Enhances a Pika's Sprint-Running Capacity in Hypoxic Environment.

    PubMed

    Wang, Yang; Wei, Lian; Wei, Dengbang; Li, Xiao; Xu, Lina; Wei, Linna

    2015-08-01

    LDH-C4 is a lactate dehydrogenase that catalyzes the conversion of pyruvate to lactate. In mammals, ldh-c was originally thought to be expressed only in testis and spermatozoa. Plateau pika (Ochotona curzoniae), which belongs to the genus Ochotona of the Ochotonidea family, is a hypoxia tolerant mammal living 3000-5000 m above sea level on the Qinghai-Tibet Plateau, an environment which is strongly hypoxic. Ldh-c is expressed not only in testis and sperm but also in somatic tissues of plateau pika. In this study, the effects of N-propyl oxamate and N-isopropyl oxamate on LDH isozyme kinetics were compared to screens for a selective inhibitor of LDH-C4. To reveal the role and physiological mechanism of LDH-C4 in skeletal muscle of plateau pika, we investigated the effect of N-isopropyl oxamate on the pika exercise tolerance as well as the physiological mechanism. Our results show that Ki of N-propyl oxamate and N-isopropyl oxamate for LDH-A4, LDH-B4, and LDH-C4 were 0.094 mmol/L and 0.462 mmol/L, 0.119 mmol/L and 0.248 mmol/L, and 0.015 mmol/L and 0.013 mmol/L, respectively. N-isopropyl oxamate is a powerful selective inhibitor of plateau pika LDH-C4. In our exercise tolerance experiment, groups treated with inhibitors had significantly lower swimming times than the uninhibited control group. The inhibition rates of LDH, LD, and ATP were 37.12%, 66.27%, and 32.42%, respectively. Our results suggested that ldh-c is expressed in the skeletal muscle of plateau pika, and at least 32.42% of ATP in the skeletal muscle is catalyzed by LDH-C4 by anaerobic glycolysis. This suggests that pika has reduced dependence on oxygen and enhanced adaptation to hypoxic environment due to increased anaerobic glycolysis by LDH-C4 in skeletal muscle. LDH-C4 in plateau pika plays the crucial role in anaerobic glycolysis and generates ATP rapidly since this is the role of LDH-A4 in most species on plain land, which provide evidence that the native humans and animals in Qinghai-Tibet plateau can adapt to the hypoxia environment. PMID:26262630

  18. Poliomyelitis in MuLV-infected ICR-SCID mice after injection of basement membrane matrix contaminated with lactate dehydrogenase-elevating virus.

    PubMed

    Carlson Scholz, Jodi A; Garg, Rohit; Compton, Susan R; Allore, Heather G; Zeiss, Caroline J; Uchio, Edward M

    2011-10-01

    The arterivirus lactate dehydrogenase-elevating virus (LDV) causes life-long viremia in mice. Although LDV infection generally does not cause disease, infected mice that are homozygous for the Fv1(n) allele are prone to develop poliomyelitis when immunosuppressed, a condition known as age-dependent poliomyelitis. The development of age-dependent poliomyelitis requires coinfection with endogenous murine leukemia virus. Even though LDV is a common contaminant of transplantable tumors, clinical signs of poliomyelitis after inadvertent exposure to LDV have not been described in recent literature. In addition, LDV-induced poliomyelitis has not been reported in SCID or ICR mice. Here we describe the occurrence of poliomyelitis in ICR-SCID mice resulting from injection of LDV-contaminated basement membrane matrix. After exposure to LDV, a subset of mice presented with clinical signs including paresis, which was associated with atrophy of the hindlimb musculature, and tachypnea; in addition, some mice died suddenly with or without premonitory signs. Mice presenting within the first 6 mo after infection had regions of spongiosis, neuronal necrosis and astrocytosis of the ventral spinal cord, and less commonly, brainstem. Axonal degeneration of ventral roots prevailed in more chronically infected mice. LDV was identified by RT-PCR in 12 of 15 mice with typical neuropathology; positive antiLDV immunolabeling was identified in all PCR-positive animals (n = 7) tested. Three of 8 mice with neuropathology but no clinical signs were LDV negative by RT-PCR. RT-PCR yielded murine leukemia virus in spinal cords of all mice tested, regardless of clinical presentation or neuropathology. PMID:22330347

  19. Evaluation of Milk Trace Elements, Lactate Dehydrogenase, Alkaline Phosphatase and Aspartate Aminotransferase Activity of Subclinical Mastitis as and Indicator of Subclinical Mastitis in Riverine Buffalo (Bubalus bubalis).

    PubMed

    Guha, Anirban; Gera, Sandeep; Sharma, Anshu

    2012-03-01

    Mastitis is a highly morbid disease that requires detection at the subclinical stage. Tropical countries like India mainly depend on milch buffaloes for milk. The present study was conducted to investigate whether the trace minerals viz. copper (Cu), iron (Fe), zinc (Zn), cobalt (Co) and manganese (Mn) and enzyme activity of lactate dehydrogenase (LDH), alkaline phosphatase (ALP) and aspartate aminotransferase (AST) in riverine buffalo milk can be used as an indicator of subclinical mastitis (SCM) with the aim of developing suitable diagnostic kit for SCM. Trace elements and enzyme activity in milk were estimated with Atomic absorption Spectrophotometer, GBC 932 plus and biochemical methods, respectively. Somatic cell count (SCC) was done microscopically. The cultural examination revealed Gram positive bacteria as the most prevalent etiological agent. A statistically significant (p<0.01) increase in SCC, Fe, Zn, Co and LDH occurred in SCM milk containing gram positive bacterial agents only. ALP was found to be elevated in milk infected by both gram positive and negative bacteria. The percent sensitivity, specificity and accuracy, predictive values and likelihood ratios were calculated taking bacterial culture examination and SCC≥2×10(5) cells/ml of milk as the benchmark. Only ALP and Zn, the former being superior, were found to be suitable for diagnosis of SCM irrespective of etiological agents. LDH, Co and Fe can be introduced in the screening programs where Gram positive bacteria are omnipresent. It is recommended that both ALP and Zn be measured together in milk to diagnose buffalo SCM, irrespective of etiology. PMID:25049573

  20. Postnatal maturation of cytochrome oxidase and lactate dehydrogenase activity and age-dependent consequences of lithium-pilocarpine status epilepticus in the rat: a regional histoenzymology study.

    PubMed

    Raffo, Emmanuel; Koning, Estelle; Nehlig, Astrid

    2004-10-01

    The lithium-pilocarpine (Li-Pilo) model of epilepsy reproduces some pathophysiological, temporal, and developmental features of human temporal lobe epilepsy. In this model, rates of cerebral glucose utilization measured by the [(14)C]2-deoxyglucose technique increased during the initial status epilepticus (SE) and decreased during the latent or chronic periods. To correlate these metabolic changes with the activities of the enzymes of the glycolytic and tricarboxylic acid cycle pathways, we measured by histoenzymology the regional activity of two key enzymes of glucose metabolism, lactate dehydrogenase (LDH) for the anaerobic pathway and cytochrome oxidase (CO) for the aerobic pathway coupled to oxidative phosphorylation, at various times after SE induced by Li-Pilo in 10- (P10), 21-d-old (P21) and adult rats for CO and in adult rats only for LDH. CO activity was slightly affected in P10 and P21 rats only at 4 and 24 h and normalized by 14 d after SE. In adult rats, CO activity decreased at 4 and 24 h in damaged areas, like entorhinal cortex, hippocampal CA3 area, amygdala, and thalamus. At 14 d after SE, CO activity was decreased only in entorhinal cortex and increased in brainstem regions involved in the remote control of seizures. In adult rats, LDH activity decreased at 24 h and 14 d after SE in sensorimotor and entorhinal cortex. These data show that the enzymatic equipment underlying the metabolism of glucose is not severely affected by Li-Pilo SE and confirm our previous observations concerning the relative metabolic hyperactivity of brain regions involved in the seizure circuit despite marked neuronal loss. PMID:15295083

  1. A study of salivary lactate dehydrogenase isoenzyme levels in patients with oral leukoplakia and squamous cell carcinoma by gel electrophoresis method

    PubMed Central

    Joshi, Priya Shirish; Golgire, Someshwar

    2014-01-01

    Context: The enzyme lactate dehydrogenase (LDH), which is found in almost all the cells of body tissues, can be separated into five fractions and the isoenzyme pattern is believed to vary according to the metabolic requirement of each tissue. LDH concentration in saliva, as an expression of cellular necrosis, could be considered to be a specific indicator for oral lesions that affect the integrity of the oral mucosa. Aim: The present study was designed to evaluate salivary LDH isoenzyme pattern in oral leukoplakia (OL) and oral squamous cell carcinoma (OSCC) and to correlate between LDH isoenzyme levels and histopathologic grading in selected cases of OL and OSCC. Materials and Methods: Clinically diagnosed 30 cases each of OL and OSCC were selected for the study and 30 healthy individuals of comparable age served as control. Unstimulated whole saliva was aseptically collected and was processed immediately for LDH isoenzymes measurement by agarose gel electrophoresis. Biopsy specimen obtained was processed and stained by hematoxylin and eosin. Sections of OL and OSCC cases were scrutinized histopathologically and appropriately graded for epithelial dysplasia and differentiation of carcinoma respectively. Statistical Analysis Used: Two sample t test for testing the significance of difference between two group means was used. Results and Conclusion: The present salivary analysis for LDH isoenzyme reveals an overall increased salivary LDH isoenzyme level in OL and OSCC cases and a significant correlation between levels of salivary LDH isoenzymes and histopathologic grades of dysplasia in OL and OSCC. Salivary analysis of LDH will definitely provide the clinician and/or the patient himself with an efficient, non invasive and friendly new tool for diagnosis and monitoring of oral precancer and cancer. PMID:25364177

  2. Karnofsky Performance Status and Lactate Dehydrogenase Predict the Benefit of Palliative Whole-Brain Irradiation in Patients With Advanced Intra- and Extracranial Metastases From Malignant Melanoma

    SciTech Connect

    Partl, Richard; Richtig, Erika; Avian, Alexander; Berghold, Andrea; Kapp, Karin S.

    2013-03-01

    Purpose: To determine prognostic factors that allow the selection of melanoma patients with advanced intra- and extracerebral metastatic disease for palliative whole-brain radiation therapy (WBRT) or best supportive care. Methods and Materials: This was a retrospective study of 87 patients who underwent palliative WBRT between 1988 and 2009 for progressive or multiple cerebral metastases at presentation. Uni- and multivariate analysis took into account the following patient- and tumor-associated factors: gender and age, Karnofsky performance status (KPS), neurologic symptoms, serum lactate dehydrogenase (LDH) level, number of intracranial metastases, previous resection or stereotactic radiosurgery of brain metastases, number of extracranial metastasis sites, and local recurrences as well as regional lymph node metastases at the time of WBRT. Results: In univariate analysis, KPS, LDH, number of intracranial metastases, and neurologic symptoms had a significant influence on overall survival. In multivariate survival analysis, KPS and LDH remained as significant prognostic factors, with hazard ratios of 3.3 (95% confidence interval [CI] 1.6-6.5) and 2.8 (95% CI 1.6-4.9), respectively. Patients with KPS ≥70 and LDH ≤240 U/L had a median survival of 191 days; patients with KPS ≥70 and LDH >240 U/L, 96 days; patients with KPS <70 and LDH ≤240 U/L, 47 days; and patients with KPS <70 and LDH >240 U/L, only 34 days. Conclusions: Karnofsky performance status and serum LDH values indicate whether patients with advanced intra- and extracranial tumor manifestations are candidates for palliative WBRT or best supportive care.

  3. Long term intensive exercise training leads to a higher plasma malate/lactate dehydrogenase (M/L) ratio and increased level of lipid mobilization in horses.

    PubMed

    Li, Gebin; Lee, Peter; Mori, Nobuko; Yamamoto, Ichiro; Arai, Toshiro

    2012-06-01

    Continuous high intensity training may induce alterations to enzyme activities related to glucose and lipid metabolism in horses. In our study, five Thoroughbred race horses (3 male and 2 female, avg age=5 yrs old) were compared against five riding horses (1 male, 1 female, 3 gelding, avg age=13 yrs old) in terms of energy metabolism, by examining plasma malate (MDH) and lactate (LDH) dehydrogenase activities and M/L ratio. MDH is involved in NADH and ATP generation, whereas LDH can convert NADH back into NAD(+) for ATP generation. An increase in plasma M/L ratio can reflect heightened energy metabolism in the liver and skeletal muscle of horses adapted to continuous intensive exercise. Moreover, plasma lipid metabolism analytes (adiponectin, NEFA, total cholesterol (T-Cho), and triglycerides (TG)) can reflect changes to lipolysis rate, which can also indicate a change in energy metabolism. Overall, race horses demonstrated increased MDH and LDH activity in plasma (4x and 2x greater, respectively), in addition to a plasma M/L ratio twice as high as that of riding horses (2.0 vs 1.0). In addition, race horses also demonstrated significantly higher levels of plasma NEFA (50% greater), TG (2x greater), and T-Cho (20% greater) as compared to riding horses. Therefore, race horse muscles may have adapted to prolonged high intensity endurance exercise by gaining a higher oxidative capacity and an increased capacity for fat utilization as an energy source, resulting in heightened energy metabolism and increased rate of lipid mobilization. PMID:22297553

  4. Dacarbazine with or without oblimersen (a Bcl-2 antisense oligonucleotide) in chemotherapy-naive patients with advanced melanoma and low-normal serum lactate dehydrogenase: 'The AGENDA trial'.

    PubMed

    Bedikian, Agop Y; Garbe, Claus; Conry, Robert; Lebbe, Celeste; Grob, Jean J

    2014-06-01

    In a previous large randomized, open-label study, retrospective subset analysis revealed that the addition of the Bcl-2 antisense oligonucleotide oblimersen to dacarbazine (Dac) significantly improved overall survival, progression-free survival, and the response rate in chemotherapy-naive patients with advanced melanoma and normal baseline serum lactate dehydrogenase (LDH) levels. To confirm and expand on this observation, we conducted a prospective double-blind, placebo-controlled study to determine whether oblimersen augmented the efficacy of Dac in advanced melanoma patients with low-normal baseline LDH levels. A total of 314 chemotherapy-naive patients were randomly assigned to receive Dac (1000 mg/m(2)) preceded by a 5-day continuous intravenous infusion of either oblimersen sodium (7 mg/kg/day) or placebo every 21 days for less than eight cycles. Co-primary efficacy endpoints were overall survival and progression-free survival. Response and progression of the disease were assessed by independent blinded review of computed tomography scan images. No difference in overall nor progression-free survival was observed between the Dac-oblimersen and Dac-placebo groups. Although the overall (17.2 vs. 12.1%) and durable (10.8 vs. 7.6%) response rates numerically favored Dac-oblimersen over Dac-placebo, they did not differ significantly (P=0.19 and 0.32, respectively). The incidence of hematologic adverse events, particularly thrombocytopenia and neutropenia, was higher in the Dac-oblimersen group than in the Dac-placebo group. Withdrawals from the study because of treatment-related adverse events were low (i.e. <2.5%) in both groups. The addition of oblimersen to Dac did not significantly improve overall survival nor progression-free survival in patients with advanced melanoma and low-normal levels of LDH at baseline. PMID:24667300

  5. Creatine supplementation does not improve sprint performance in competitive swimmers.

    PubMed

    Mujika, I; Chatard, J C; Lacoste, L; Barale, F; Geyssant, A

    1996-11-01

    This study was conducted to examine the effects of creatine (Cr) supplementation on sprint swimming performance and energy metabolism. Twenty highly trained swimmers (9 female, 11 male) were tested for blood ammonia and for blood lactate after the 25-, 50-, and 100-m performance in their best stroke on two occasions 7 d apart. After the first trial, subjects were evenly and randomly assigned to either a creatine (5 g creatine monohydrate 4 times per day for 5 d) or a placebo group (same dosage of a lactose placebo) in a double-blind research design. No significant differences in performance times were observed between trials. Post-exercise blood ammonia concentration decreased in the 50- and 100-m trials in the creatine group and in the 50-m trial in the placebo group. The supplementation period had no effect on post-exercise blood lactate. Therefore, creatine supplementation cannot be considered as an ergogenic aid for sprint performance in highly trained swimmers although adenine nucleotide degradation may be reduced during sprint exercise after 5 d of creatine ingestion. PMID:8933496

  6. Creatine supplementation and oxidative stress in rat liver

    PubMed Central

    2013-01-01

    Background The objective of this study was to determine the effects of creatine supplementation on liver biomarkers of oxidative stress in exercise-trained rats. Methods Forty 90-day-old adult male Wistar rats were assigned to four groups for the eight-week experiment. Control group (C) rats received a balanced control diet; creatine control group (CCr) rats received a balanced diet supplemented with 2% creatine; trained group (T) rats received a balanced diet and intense exercise training equivalent to the maximal lactate steady state phase; and supplemented-trained (TCr) rats were given a balanced diet supplemented with 2% creatine and subjected to intense exercise training equivalent to the maximal lactate steady state phase. At the end of the experimental period, concentrations of creatine, hydrogen peroxide (H2O2) and thiobarbituric acid reactive substances (TBARS) were measured as well as the enzyme activity of superoxide dismutase (SOD), glutathione peroxidase (GSH-GPx) and catalase (CAT). Liver tissue levels of reduced glutathione (GSH), oxidized glutathione (GSSG) and the GSH/GSSG ratio were also determined. Results Hepatic creatine levels were highest in the CCr and TCr groups with increased concentration of H2O2 observed in the T and TCr animal groups. SOD activity was decreased in the TCr group. GSH-GPx activity was increased in the T and TCr groups while CAT was elevated in the CCr and TCr groups. GSH, GGS and the GSH/GSSG ratio did not differ between all animal subsets. Conclusions Our results demonstrate that creatine supplementation acts in an additive manner to physical training to raise antioxidant enzymes in rat liver. However, because markers of liver oxidative stress were unchanged, this finding may also indicate that training-induced oxidative stress cannot be ameliorated by creatine supplementation. PMID:24325803

  7. Chitosan promotes immune responses, ameliorates glutamic oxaloacetic transaminase and glutamic pyruvic transaminase, but enhances lactate dehydrogenase levels in normal mice in vivo

    PubMed Central

    YEH, MING-YANG; SHIH, YUNG-LUEN; CHUNG, HSUEH-YU; CHOU, JASON; LU, HSU-FENG; LIU, CHIA-HUI; LIU, JIA-YOU; HUANG, WEN-WEN; PENG, SHU-FEN; WU, LUNG-YUAN; CHUNG, JING-GUNG

    2016-01-01

    Chitosan, a naturally derived polymer, has been shown to possess antimicrobial and anti-inflammatory properties; however, little is known about the effect of chitosan on the immune responses and glutamic oxaloacetic transaminase (GOT), glutamic pyruvic transaminase (GPT) and lactate dehydrogenase (LDH) activities in normal mice. The aim of the present study was to investigate whether chitosan has an effect on the immune responses and GOT, GPT and LDH activities in mice in vivo. BALB/c mice were divided into four groups. The negative control group was treated with a normal diet; the positive control group was treated with a normal diet plus orally administered acetic acid and two treatment groups were treated with a normal diet plus orally administered chitosan in acetic acid at doses of 5 and 20 mg/kg, respectively, every other day for 24 days. Mice were weighed during the treatment, and following the treatment, blood was collected, and liver and spleen samples were isolated and weighted. The blood samples were used for measurement of white blood cell markers, and the spleen samples were used for analysis of phagocytosis, natural killer (NK) cell activity and cell proliferation using flow cytometry. The results indicated that chitosan did not markedly affect the body, liver and spleen weights at either dose. Chitosan increased the percentages of CD3 (T-cell marker), CD19 (B-cell marker), CD11b (monocytes) and Mac-3 (macrophages) when compared with the control group. However, chitosan did not affect the phagocytic activity of macrophages in peripheral blood mononuclear cells, although it decreased it in the peritoneal cavity. Treatment with 20 mg/kg chitosan led to a reduction in the cytotoxic activity of NK cells at an effector to target ratio of 25:1. Chitosan did not significantly promote B-cell proliferation in lipopolysaccharide-pretreated cells, but significantly decreased T-cell proliferation in concanavalin A-pretreated cells, and decreased the activity of GOT and GPT compared with that in the acetic acid-treated group,. In addition, it significantly increased LDH activity, to a level similar to that in normal mice, indicating that chitosan can protect against liver injury. PMID:27073440

  8. Creatine supplementation and exercise performance.

    PubMed

    Maughan, R J

    1995-06-01

    Creatine phosphate allows high rates of adenosine triphosphate resynthesis to occur in muscle and therefore plays a vital role in the performance of high-intensity exercise. Recent studies have shown that feeding large amounts of creatine (typically 20 g per day for 5 days) increases muscle total creatine (and phosphocreatine) content. The extent of the increase that is normally observed is inversely related to the presupplementation level. Vegetarians, who have a very low dietary creatine intake, generally show the largest increases. Creatine supplementation has been shown to increase performance in situations where the availability of creatine phosphate is important; thus, performance is improved in very high-intensity exercise and especially where repeated sprints are performed with short recovery periods. Creatine supplementation is widely practiced by athletes in many sports and does not contravene current doping regulations. There are no reports of harmful side effects at the recommended dosage. PMID:7670456

  9. Creatine and creatine deficiency syndromes: biochemical and clinical aspects.

    PubMed

    Nasrallah, Fahmi; Feki, Moncef; Kaabachi, Naziha

    2010-03-01

    Creatine deficiency syndromes, which have only recently been described, represent a group of inborn errors of creatine synthesis (L-arginine-glycine amidinotransferase deficiency and guanidinoacetate methyltransferase deficiency) and transport (creatine transporter deficiency). Patients with creatine deficiency syndromes present with mental retardation expressive speech and language delay, and epilepsy. Patients with guanidinoacetate methyltransferase deficiency or creatine transporter deficiency may exhibit autistic behavior. The common denominator of these disorders is the depletion of the brain creatine pool, as demonstrated by in vivo proton magnetic resonance spectroscopy. For diagnosis, laboratory investigations start with analysis of guanidinoacetate, creatine, and creatinine in plasma and urine. Based on these findings, enzyme assays or DNA mutation analysis may be performed. The creatine deficiency syndromes are underdiagnosed, so the possibility should be considered in all children affected by unexplained mental retardation, seizures, and speech delay. Guanidinoacetate methyltransferase deficiency and arginine-glycine amidinotransferase deficiency are treatable by oral creatine supplementation, but patients with creatine transporter deficiency do not respond to this type of treatment. PMID:20159424

  10. Efficient reduction of the formation of by-products and improvement of production yield of 2,3-butanediol by a combined deletion of alcohol dehydrogenase, acetate kinase-phosphotransacetylase, and lactate dehydrogenase genes in metabolically engineered Klebsiella oxytoca in mineral salts medium.

    PubMed

    Jantama, Kaemwich; Polyiam, Pattharasedthi; Khunnonkwao, Panwana; Chan, Sitha; Sangproo, Maytawadee; Khor, Kirin; Jantama, Sirima Suvarnakuta; Kanchanatawee, Sunthorn

    2015-07-01

    Klebsiella oxytoca KMS005 (∆adhE∆ackA-pta∆ldhA) was metabolically engineered to improve 2,3-butanediol (BDO) yield. Elimination of alcohol dehydrogenase E (adhE), acetate kinase A-phosphotransacetylase (ackA-pta), and lactate dehydrogenase A (ldhA) enzymes allowed BDO production as a primary pathway for NADH re-oxidation, and significantly reduced by-products. KMS005 was screened for the efficient glucose utilization by metabolic evolution. KMS005-73T improved BDO production at a concentration of 23.5±0.5 g/L with yield of 0.46±0.02 g/g in mineral salts medium containing 50 g/L glucose in a shake flask. KMS005-73T also exhibited BDO yields of about 0.40-0.42 g/g from sugarcane molasses, cassava starch, and maltodextrin. During fed-batch fermentation, KMS005-73T produced BDO at a concentration, yield, and overall and specific productivities of 117.4±4.5 g/L, 0.49±0.02 g/g, 1.20±0.05 g/Lh, and 27.2±1.1 g/gCDW, respectively. No acetoin, lactate, and formate were detected, and only trace amounts of acetate and ethanol were formed. The strain also produced the least by-products and the highest BDO yield among other Klebsiella strains previously developed. PMID:25895450

  11. Metabolism of D- and L-lactate by Pseudomonas putida.

    PubMed

    O'Brien, R W

    1977-12-01

    Pseudomonas putida grew at the same rate with the same molar growth yield on D-, L, or DL-lactate as the sole source of carbon for growth. D- and L- lactate were utilized simultaneously and at the same rate when the organism was grown on DL-lactate (ratio of D isomer to L isomer of 1:1). Growth on either isomer alone, or in combination, caused the induction of both a D-lactate, and an L-lactate dehydrogenase. Both enzymes were particulate and used dichlorophenolindophenol, or oxygen, but not NAD, as electron acceptor, and were inhibited by cyanide when oxygen was the electron acceptor. The pH optimum for the D-lactate dehydrogenase was about 6.5, and for the L-lactate dehydrogenase was about 8.0. The D-lactate dehydrogenase was more heat-sensitive than the L-lactate dehydrogenase. The stoichiometry of both enzyme reactions was the same with 2 mol of lactate dehydrogenase. The stoichiometry of both enzyme reactions was the same with 2 mol of lactate being oxidized by 1 mol of oxygen to form 2 mol of pyruvate. No lactate racemase was detected in the cell extracts. PMID:614007

  12. Equating salivary lactate dehydrogenase (LDH) with LDH-5 expression in patients with oral squamous cell carcinoma: An insight into metabolic reprogramming of cancer cell as a predictor of aggressive phenotype.

    PubMed

    Saluja, Tajindra Singh; Spadigam, Anita; Dhupar, Anita; Syed, Shaheen

    2016-04-01

    Oral squamous cell carcinoma (OSCC) is the sixth most common human malignancy. According to World Health Organization, oral cancer has been reported to have the highest morbidity and mortality and a survival rate of approximately 50 % at 5 years from diagnosis. This is attributed to the subjectivity in TNM staging and histological grading which may result in less than optimum treatment outcomes including tumour recurrence. One of the hallmarks of cancer is aerobic glycolysis also known as the Warburg effect. This glycolytic phenotype (hypoxic state) not only confers immortality to cancer cells, but also correlates with the belligerent behaviour of various malignancies and is reflected as an increase in the expression of lactate dehydrogenase 5 (LDH-5), the main isoform of LDH catalysing the conversion of pyruvate to lactate during glycolysis. The diagnostic role of salivary LDH in assessing the metabolic phenotype of oral cancer has not been studied. Since salivary LDH is mainly sourced from oral epithelial cells, any pathological changes in the epithelium should reflect diagnostically in saliva. Thus in our current research, we made an attempt to ascertain the biological behaviour and aggressiveness of OSCC by appraising its metabolic phenotype as indirectly reflected in salivary LDH activity. We found that salivary LDH can be used to assess the aggressiveness of different histological grades of OSCC. For the first time, an evidence of differing metabolic behaviour in similar histologic tumour grade is presented. Taken together, our study examines the inclusion of salivary LDH as potential diagnostic parameter and therapeutic index in OSCC. PMID:26577856

  13. Testicular lactate content is compromised in men with Klinefelter Syndrome.

    PubMed

    Alves, Marco G; Martins, Ana D; Jarak, Ivana; Barros, Alberto; Silva, Joaquina; Sousa, Mário; Oliveira, Pedro F

    2016-03-01

    Klinefelter syndrome (KS) is the most common genetic cause of human infertility, but the mechanism(s) responsible for its phenotype remain largely unknown. KS is associated with alterations in body composition and with a higher risk of developing metabolic diseases. We therefore hypothesized that KS men seeking fertility treatment possess an altered testicular metabolism profile that may hamper the nutritional support of spermatogenesis. Testicular biopsies from control (46, XY) (n = 6) and KS (47, XXY) (n = 6) individuals were collected and analyzed by proton high-resolution magic-angle spinning nuclear magnetic resonance spectroscopy. The mRNA and protein expression of crucial glycolysis-associated enzymes and transporters were evaluated in parallel by quantitative PCR and Western blot, respectively. Our data revealed altered regulation of glucose transporters (GLUT1 and GLUT3); phosphofructokinase 1, liver isoform (PFKL); and lactate dehydrogenase A (LDHA) expression in the testis of KS patients. Moreover, we detected a severe reduction in lactate and creatine accumulation within testicular tissue from KS men. The aberrant levels of the biomarkers detected in testicular biopsies of KS men may therefore be associated with the infertility phenotypes presented by these men. Mol. Reprod. Dev. 83: 208-216, 2016. © 2015 Wiley Periodicals, Inc. PMID:26676340

  14. Protective effects of ranolazine in guinea-pig hearts during low-flow ischaemia and their association with increases in active pyruvate dehydrogenase.

    PubMed Central

    Clarke, B.; Spedding, M.; Patmore, L.; McCormack, J. G.

    1993-01-01

    1. In isolated Langendorff-perfused, electrically-paced, hearts of guinea-pigs, global low-flow-ischaemia (LFI; at 0.7 ml min-1) resulted in marked increases in the rates of release of lactate, lactate dehydrogenase (LDH) and creatine kinase (CK) over a 30 min period. At the end of the LFI period, tissue ATP content was significantly reduced from a control value of 11.8 +/- 0.8 (5) to 5.6 +/- 0.8 (5) mumol g-1 dry weight. 2. The presence of ranolazine [(+/-)-N-(2,6-dimethyl-phenyl)-4[2-hydroxy-3-(2-methoxy-phenoxyl)- propyl] - l-piperazine acetamide dihydro-chloride; RS-43285-193] at 10 microM, from 20 min prior to and during LFI, resulted in significant reductions in the release of lactate, LDH and CK during the ischaemic period and a significant preservation of tissue ATP (9.0 +/- 1.1 (6) mumol g-1 dry wt.). Ranolazine did not prevent the reductions in creatine phosphate or glycogen observed in LFI, nor did it have any significant effects on any contractile parameters before or during the LFI period. 3. Neither ranolazine nor LFI affected the total amounts of tissue pyruvate dehydrogenase (PDH) activity; however, the significant reduction in the amount of active, non-phosphorylated PDH caused by LFI (from 88.2 +/- 5.5 to 44.2 +/- 3.2% of total activity) was partially but significantly prevented by ranolazine (67.2 +/- 6.8%). This effect of ranolazine on PDH may be part of the mechanism whereby the compound reduces lactate release and preserves tissue ATP during ischaemia. PMID:8358570

  15. Elevated levels of plasma lactate dehydrogenase is an unfavorable prognostic factor in patients with epidermal growth factor receptor mutation-positive non-small cell lung cancer, receiving treatment with gefitinib or erlotinib

    PubMed Central

    INOMATA, MINEHIKO; HAYASHI, RYUJI; TANAKA, HIROAKI; SHIMOKAWA, KAZUKI; TOKUI, KOTARO; TAKA, CHIHIRO; OKAZAWA, SEISUKE; KAMBARA, KENTA; ICHIKAWA, TOMOMI; YAMADA, TORU; MIWA, TOSHIRO; KASHII, TATSUHIKO; MATSUI, SHOKO; TOBE, KAZUYUKI

    2016-01-01

    Treatment with epidermal growth factor receptor-tyrosine kinase inhibitors (EGFR-TKIs) has been shown to prolong survival in patients with EGFR mutation-positive non-small cell lung cancer (NSCLC). The present study performed a retrospective analysis to investigate the association between the plasma lactate dehydrogenase (LDH) levels and survival in patients with EGFR mutation-positive NSCLC receiving treatment with EGFR-TKIs. The medical charts of patients with EGFR mutation-positive NSCLC who were receiving treatment with EGFR-TKIs at Toyama University Hospital between 2007 and 2014 were assessed. The data from 65 patients were included in the analysis. Patients with higher plasma LDH levels exhibited shorter progression-free survival (6.2 vs. 13.2 months; P<0.01) and overall survival (10.5 vs. 36.1 months; P<0.01) periods compared with patients with lower plasma LDH levels. A Cox proportional hazards model identified that the plasma LDH level was associated with the progression-free survival (P=0.05) and overall survival (P<0.01). An association was demonstrated between the pretreatment plasma LDH level and the survival in patients with EGFR mutation-positive NSCLC receiving treatment with EGFR-TKIs. Close observation is required in EGFR mutation-positive NSCLC patients exhibiting high plasma LDH levels following the initiation of treatment with EGFR-TKIs.

  16. C58 and AKR mice of all ages develop motor neuron disease after lactate dehydrogenase-elevating virus infection but only if antiviral immune responses are blocked by chemical or genetic means or as a result of old age.

    PubMed

    Anderson, G W; Even, C; Rowland, R R; Palmer, G A; Harty, J T; Plagemann, P G

    1995-09-01

    Age-dependent poliomyelitis is a paralytic disease of C58 and AKR mice caused by cytocidal infection of anterior horn neurons with neuropathogenic strains of lactate dehydrogenase-elevating virus (LDV). The motor neurons are rendered LDV-permissive via an unknown mechanism through the expression of ecotropic murine leukemia virus (MuLV) in central nervous system (CNS) glial cells. Only old mice develop paralytic disease after LDV infection, but mice 5-6 months old or older can be rendered susceptible by suppression of anti-LDV immune responses by a single treatment with cyclophosphamide or X-irradiation before LDV infection. Younger mice appeared to be resistant in spite of this immunosuppresive treatment. The present results confirm that mice as young as 1 month of age possess CNS cells expressing ecotropic MuLV and show that these mice are susceptible to paralytic LDV infection provided their anti-LDV immune responses are blocked for an extended period of time by repeated cyclophosphamide treatments or by a genetic defect. Furthermore, old mice become naturally susceptible to paralytic LDV infection because of an impaired ability to mount a motor neuron protective anti-LDV immune response. PMID:9222362

  17. Efficient Production of Optically Pure d-Lactic Acid from Raw Corn Starch by Using a Genetically Modified l-Lactate Dehydrogenase Gene-Deficient and α-Amylase-Secreting Lactobacillus plantarum Strain▿

    PubMed Central

    Okano, Kenji; Zhang, Qiao; Shinkawa, Satoru; Yoshida, Shogo; Tanaka, Tsutomu; Fukuda, Hideki; Kondo, Akihiko

    2009-01-01

    In order to achieve direct and efficient fermentation of optically pure d-lactic acid from raw corn starch, we constructed l-lactate dehydrogenase gene (ldhL1)-deficient Lactobacillus plantarum and introduced a plasmid encoding Streptococcus bovis 148 α-amylase (AmyA). The resulting strain produced only d-lactic acid from glucose and successfully expressed amyA. With the aid of secreting AmyA, direct d-lactic acid fermentation from raw corn starch was accomplished. After 48 h of fermentation, 73.2 g/liter of lactic acid was produced with a high yield (0.85 g per g of consumed sugar) and an optical purity of 99.6%. Moreover, a strain replacing the ldhL1 gene with an amyA-secreting expression cassette was constructed. Using this strain, direct d-lactic acid fermentation from raw corn starch was accomplished in the absence of selective pressure by antibiotics. This is the first report of direct d-lactic acid fermentation from raw starch. PMID:19011066

  18. Efficient production of optically pure D-lactic acid from raw corn starch by using a genetically modified L-lactate dehydrogenase gene-deficient and alpha-amylase-secreting Lactobacillus plantarum strain.

    PubMed

    Okano, Kenji; Zhang, Qiao; Shinkawa, Satoru; Yoshida, Shogo; Tanaka, Tsutomu; Fukuda, Hideki; Kondo, Akihiko

    2009-01-01

    In order to achieve direct and efficient fermentation of optically pure D-lactic acid from raw corn starch, we constructed L-lactate dehydrogenase gene (ldhL1)-deficient Lactobacillus plantarum and introduced a plasmid encoding Streptococcus bovis 148 alpha-amylase (AmyA). The resulting strain produced only D-lactic acid from glucose and successfully expressed amyA. With the aid of secreting AmyA, direct D-lactic acid fermentation from raw corn starch was accomplished. After 48 h of fermentation, 73.2 g/liter of lactic acid was produced with a high yield (0.85 g per g of consumed sugar) and an optical purity of 99.6%. Moreover, a strain replacing the ldhL1 gene with an amyA-secreting expression cassette was constructed. Using this strain, direct D-lactic acid fermentation from raw corn starch was accomplished in the absence of selective pressure by antibiotics. This is the first report of direct D-lactic acid fermentation from raw starch. PMID:19011066

  19. [The development of transaminase activity (SGOT and SGPT), lactate dehydrogenase and alkaline phosphatase in the blood plasma of calves up to the age of 4 months].

    PubMed

    Surynek, J; Kucera, A; Janů, J

    1976-11-01

    A trial was performed in 204 healthy calves (heifers) of the Bohemian Spotted breed in the post-natal period from birth to the age of four months. The activities of the following enzymes in blood plasma were determined: L-aspartate: 2-oxoglutarate: aminotransferase, EC.2.6.1.1. (GOT), L-alanine: oxoglutarate: aminotransferase, EC.2.6.1.2. (GPT), L-lactate: NAD oxidoreductase, EC.1.1.1.27 (LDH), and orthophosphoric acid monoester phosphohydrolase, EC.3.1.3.1. (alkaline phosphatase). The calves were divided into age categories according to the date of birth with an interval of one week. GOT activity in blood plasma increased significantly until the age of eight weeks (from the original value of 1.1708 +/- 0.2598 micronmol ml-1 to 1.8150 +/- 0.6362 micronmol ml-1, with the maximum of 2.0317 +/- 0.7777 micronmol ml-1 of plasma in the sixth week). In the subsequent period the GOT curve has not a characteristic course. While the activity of GOT increased in the first weeks after birth, the activity of GPT showed a significant drop (from the original level of 0.9000 +/- 0.3364 micronmol ml-1 to the minimum of 0.3675 +/- 0.1901 micronmol ml-1 of plasma in the seventh week); from the 10th week on the values rise so that at the end of the period of study they reach almost the same levels as in calves in the first postnatal week. The activity of LDH in blood plasma remains at almost the same level in the first five weeks after birth (between 43.4025 +/- 8.4893 micronmol ml-1 and 46.3792 +/- 14.8952 micronmol ml-1 of plasma); it was at a statistically significantly higher level only in a short period between the 7th and 10th week after birth. The highest values of alkaline phosphatase in blood plasma were recorded at the age of two or three weeks (maximum in the second week 23.9833 +/- 9.0945 micronmol ml-1 of plasma); from the fourth week on, the values of alkaline phosphatase are significantly lower until the end of the test period, ranging betweek 5.3133 +/- 1.6017 micronmol ml-1 and 7.5425 +/- 2.2437 micronmol ml-1 of plasma. Changes conditioned by postnatal development were observed in the development of all the enzymatic activities under study, the greatest changes being observed in alkaline phosphatase. PMID:828994

  20. Creatine supplementation prevents the accumulation of fat in the livers of rats fed a high-fat diet.

    PubMed

    Deminice, Rafael; da Silva, Robin P; Lamarre, Simon G; Brown, Colin; Furey, George N; McCarter, Shannon A; Jordao, Alceu Afonso; Kelly, Karen B; King-Jones, Kirst; Jacobs, Ren L; Brosnan, Margaret E; Brosnan, John T

    2011-10-01

    The aim of the present study was to examine the effects of creatine supplementation on liver fat accumulation induced by a high-fat diet in rats. Rats were fed 1 of 3 different diets for 3 wk: a control liquid diet (C), a high-fat liquid diet (HF), or a high-fat liquid diet supplemented with creatine (HFC). The C and HF diets contained, respectively, 35 and 71% of energy derived from fat. Creatine supplementation involved the addition of 1% (wt:v) of creatine monohydrate to the liquid diet. The HF diet increased total liver fat concentration, liver TG, and liver TBARS and decreased the hepatic S-adenosylmethionine (SAM) concentration. Creatine supplementation normalized all of these perturbations. Creatine supplementation significantly decreased the renal activity of l-arginine:glycine amidinotransferase and plasma guanidinoacetate and prevented the decrease in hepatic SAM concentration in rats fed the HF diet. However, there was no change in either the phosphatidylcholine:phosphatidylethanolamine (PE) ratio or PE N-methyltransferase activity. The HF diet decreased mRNA for PPAR? as well as 2 of its targets, carnitine palmitoyltransferase and long-chain acylCoA dehydrogenase. Creatine supplementation normalized these mRNA levels. In conclusion, creatine supplementation prevented the fatty liver induced by feeding rats a HF diet, probably by normalization of the expression of key genes of ?-oxidation. PMID:21880953

  1. Creatine kinase overexpression improves ATP kinetics and contractile function in postischemic myocardium

    PubMed Central

    Akki, Ashwin; Su, Jason; Yano, Toshiyuki; Gupta, Ashish; Wang, Yibin; Leppo, Michelle K.; Chacko, Vadappuram P.; Steenbergen, Charles

    2012-01-01

    Reduced myofibrillar ATP availability during prolonged myocardial ischemia may limit post-ischemic mechanical function. Because creatine kinase (CK) is the prime energy reserve reaction of the heart and because it has been difficult to augment ATP synthesis during and after ischemia, we used mice that overexpress the myofibrillar isoform of creatine kinase (CKM) in cardiac-specific, conditional fashion to test the hypothesis that CKM overexpression increases ATP delivery in ischemic-reperfused hearts and improves functional recovery. Isolated, retrograde-perfused hearts from control and CKM mice were subjected to 25 min of global, no-flow ischemia and 40 min of reperfusion while cardiac function [rate pressure product (RPP)] was monitored. A combination of 31P-nuclear magnetic resonance experiments at 11.7T and biochemical assays was used to measure the myocardial rate of ATP synthesis via CK (CK flux) and intracellular pH (pHi). Baseline CK flux was severalfold higher in CKM hearts (8.1 ± 1.0 vs. 32.9 ± 3.8, mM/s, control vs. CKM; P < 0.001) with no differences in phosphocreatine concentration [PCr] and RPP. End-ischemic pHi was higher in CKM hearts than in control hearts (6.04 ± 0.12 vs. 6.37 ± 0.04, control vs. CKM; P < 0.05) with no differences in [PCr] and [ATP] between the two groups. Post-ischemic PCr (66.2 ± 1.3 vs. 99.1 ± 8.0, %preischemic levels; P < 0.01), CK flux (3.2 ± 0.4 vs. 14.0 ± 1.2 mM/s; P < 0.001) and functional recovery (13.7 ± 3.4 vs. 64.9 ± 13.2%preischemic RPP; P < 0.01) were significantly higher and lactate dehydrogenase release was lower in CKM than in control hearts. Thus augmenting cardiac CKM expression attenuates ischemic acidosis, reduces injury, and improves not only high-energy phosphate content and the rate of CK ATP synthesis in postischemic myocardium but also recovery of contractile function. PMID:22886411

  2. Infection of central nervous system cells by ecotropic murine leukemia virus in C58 and AKR mice and in in utero-infected CE/J mice predisposes mice to paralytic infection by lactate dehydrogenase-elevating virus.

    PubMed

    Anderson, G W; Palmer, G A; Rowland, R R; Even, C; Plagemann, P G

    1995-01-01

    Certain mouse strains, such as AKR and C58, which possess N-tropic, ecotropic murine leukemia virus (MuLV) proviruses and are homozygous at the Fv-1n locus are specifically susceptible to paralytic infection (age-dependent poliomyelitis [ADPM]) by lactate dehydrogenase-elevating virus (LDV). Our results provide an explanation for this genetic linkage and directly prove that ecotropic MuLV infection of spinal cord cells is responsible for rendering anterior horn neurons susceptible to cytocidal LDV infection, which is the cause of the paralytic disease. Northern (RNA) blot hybridization of total tissue RNA and in situ hybridization of tissue sections demonstrated that only mice harboring central nervous system (CNS) cells that expressed ecotropic MuLV were susceptible to ADPM. Our evidence indicates that the ecotropic MuLV RNA is transcribed in CNS cells from ecotropic MuLV proviruses that have been acquired by infection with exogenous ecotropic MuLV, probably during embryogenesis, the time when germ line proviruses in AKR and C58 mice first become activated. In young mice, MuLV RNA-containing cells were found exclusively in white-matter tracts and therefore were glial cells. An increase in the ADPM susceptibility of the mice with advancing age correlated with the presence of an increased number of ecotropic MuLV RNA-containing cells in the spinal cords which, in turn, correlated with an increase in the number of unmethylated proviruses in the DNA extracted from spinal cords. Studies with AKXD recombinant inbred strains showed that possession of a single replication-competent ecotropic MuLV provirus (emv-11) by Fv-1n/n mice was sufficient to result in ecotropic MuLV infection of CNS cells and ADPM susceptibility. In contrast, no ecotropic MuLV RNA-positive cells were present in the CNSs of mice carrying defective ecotropic MuLV proviruses (emv-3 or emv-13) or in which ecotropic MuLV replication was blocked by the Fv-1n/b or Fv-1b/b phenotype. Such mice were resistant to paralytic LDV infection. In utero infection of CE/J mice, which are devoid of any endogenous ecotropic MuLVs, with the infectious clone of emv-11 (AKR-623) resulted in the infection of CNS cells, and the mice became ADPM susceptible, whereas littermates that had not become infected with ecotropic MuLV remained ADPM resistant. PMID:7983723

  3. Combining Parasite Lactate Dehydrogenase-Based and Histidine-Rich Protein 2-Based Rapid Tests To Improve Specificity for Diagnosis of Malaria Due to Plasmodium knowlesi and Other Plasmodium Species in Sabah, Malaysia

    PubMed Central

    William, Timothy; Barber, Bridget E.; Parameswaran, Uma; Bird, Elspeth; Piera, Kim; Aziz, Ammar; Dhanaraj, Prabakaran; Yeo, Tsin W.; Anstey, Nicholas M.

    2014-01-01

    Plasmodium knowlesi causes severe and fatal malaria in Malaysia. Microscopic misdiagnosis is common and may delay appropriate treatment. P. knowlesi can cross-react with “species-specific” parasite lactate dehydrogenase (pLDH) monoclonal antibodies used in rapid diagnostic tests (RDTs) to detect P. falciparum and P. vivax. At one tertiary-care hospital and two district hospitals in Sabah, we prospectively evaluated two combination RDTs for malaria diagnosis by using both a pan-Plasmodium-pLDH (pan-pLDH)/P. falciparum-specific-pLDH (Pf-pLDH) RDT (OptiMAL-IT) and a non-P. falciparum VOM-pLDH/Pf-HRP2 RDT (CareStart). Differential cross-reactivity among these combinations was hypothesized to differentiate P. knowlesi from other Plasmodium monoinfections. Among 323 patients with PCR-confirmed P. knowlesi (n = 193), P. falciparum (n = 93), and P. vivax (n = 37) monoinfections, the VOM-pLDH individual component had the highest sensitivity for nonsevere (35%; 95% confidence interval [CI], 27 to 43%) and severe (92%; CI, 81 to 100%) P. knowlesi malaria. CareStart demonstrated a P. knowlesi sensitivity of 42% (CI, 34 to 49%) and specificity of 74% (CI, 65 to 82%), a P. vivax sensitivity of 83% (CI, 66 to 93%) and specificity of 71% (CI, 65 to 76%), and a P. falciparum sensitivity of 97% (CI, 90 to 99%) and specificity of 99% (CI, 97 to 100%). OptiMAL-IT demonstrated a P. knowlesi sensitivity of 32% (CI, 25 to 39%) and specificity of 21% (CI, 15 to 29%), a P. vivax sensitivity of 60% (CI, 42 to 75%) and specificity of 97% (CI, 94 to 99%), and a P. falciparum sensitivity of 82% (CI, 72 to 89%) and specificity of 39% (CI, 33 to 46%). The combination of CareStart plus OptiMAL-IT for P. knowlesi using predefined criteria gave a sensitivity of 25% (CI, 19 to 32%) and specificity of 97% (CI, 92 to 99%). Combining two RDT combinations was highly specific for P. knowlesi malaria diagnosis; however, sensitivity was poor. The specificity of pLDH RDTs was decreased for P. vivax and P. falciparum because of P. knowlesi cross-reactivity and cautions against their use alone in areas where P. knowlesi malaria is endemic. Sensitive P. knowlesi-specific RDTs and/or alternative molecular diagnostic tools are needed in areas where P. knowlesi malaria is endemic. PMID:24696029

  4. Combining parasite lactate dehydrogenase-based and histidine-rich protein 2-based rapid tests to improve specificity for diagnosis of malaria Due to Plasmodium knowlesi and other Plasmodium species in Sabah, Malaysia.

    PubMed

    Grigg, Matthew J; William, Timothy; Barber, Bridget E; Parameswaran, Uma; Bird, Elspeth; Piera, Kim; Aziz, Ammar; Dhanaraj, Prabakaran; Yeo, Tsin W; Anstey, Nicholas M

    2014-06-01

    Plasmodium knowlesi causes severe and fatal malaria in Malaysia. Microscopic misdiagnosis is common and may delay appropriate treatment. P. knowlesi can cross-react with "species-specific" parasite lactate dehydrogenase (pLDH) monoclonal antibodies used in rapid diagnostic tests (RDTs) to detect P. falciparum and P. vivax. At one tertiary-care hospital and two district hospitals in Sabah, we prospectively evaluated two combination RDTs for malaria diagnosis by using both a pan-Plasmodium-pLDH (pan-pLDH)/P. falciparum-specific-pLDH (Pf-pLDH) RDT (OptiMAL-IT) and a non-P. falciparum VOM-pLDH/Pf-HRP2 RDT (CareStart). Differential cross-reactivity among these combinations was hypothesized to differentiate P. knowlesi from other Plasmodium monoinfections. Among 323 patients with PCR-confirmed P. knowlesi (n = 193), P. falciparum (n = 93), and P. vivax (n = 37) monoinfections, the VOM-pLDH individual component had the highest sensitivity for nonsevere (35%; 95% confidence interval [CI], 27 to 43%) and severe (92%; CI, 81 to 100%) P. knowlesi malaria. CareStart demonstrated a P. knowlesi sensitivity of 42% (CI, 34 to 49%) and specificity of 74% (CI, 65 to 82%), a P. vivax sensitivity of 83% (CI, 66 to 93%) and specificity of 71% (CI, 65 to 76%), and a P. falciparum sensitivity of 97% (CI, 90 to 99%) and specificity of 99% (CI, 97 to 100%). OptiMAL-IT demonstrated a P. knowlesi sensitivity of 32% (CI, 25 to 39%) and specificity of 21% (CI, 15 to 29%), a P. vivax sensitivity of 60% (CI, 42 to 75%) and specificity of 97% (CI, 94 to 99%), and a P. falciparum sensitivity of 82% (CI, 72 to 89%) and specificity of 39% (CI, 33 to 46%). The combination of CareStart plus OptiMAL-IT for P. knowlesi using predefined criteria gave a sensitivity of 25% (CI, 19 to 32%) and specificity of 97% (CI, 92 to 99%). Combining two RDT combinations was highly specific for P. knowlesi malaria diagnosis; however, sensitivity was poor. The specificity of pLDH RDTs was decreased for P. vivax and P. falciparum because of P. knowlesi cross-reactivity and cautions against their use alone in areas where P. knowlesi malaria is endemic. Sensitive P. knowlesi-specific RDTs and/or alternative molecular diagnostic tools are needed in areas where P. knowlesi malaria is endemic. PMID:24696029

  5. Creatine as nutritional supplementation and medicinal product.

    PubMed

    Benzi, G; Ceci, A

    2001-03-01

    Because of assumed ergogenic effects, the creatine administration has become popular practice among subjects participating in different sports. Appropriate creatine monohydrate dosage may be considered a medicinal product since, in accordance with the Council Directive 65/65/EEC, any substance which may be administered with a view to restoring, correcting or modifying physiological functions in humans beings is considered a medicinal product. Thus, quality, efficacy and safety must characterise the substance. In addition, the European Court of Justice has held that a product which is recommended or described as having preventive or curative properties is a medicinal product even if it is generally considered as a foodstuff and even if it has no known therapeutic effect in the present state of scientific knowledge. In biochemical terms, creatine administration increases creatine and phosphocreatine muscle concentration, allowing for an accelerated rate of ATP synthesis. In thermodynamics terms, creatine stimulates the creatine-creatine kinase-phosphocreatine circuit, which is related to the mitochondrial function as a highly organised system for the control of the subcellular adenylate pool. In pharmacokinetics terms, creatine entry into skeletal muscle is initially dependent on the extracellular concentration, but the creatine transport is subsequently downregulated. In pharmacodynamics terms, the creatine enhances the possibility to maintain power output during brief periods of high-intensity exercises. In spite of uncontrolled daily dosage and long-term administration, no researches on creatine monohydrate safety in humans were set up by standardised protocols of clinical pharmacology and toxicology, as currently occurs in phases I and II for products for human use. More or less documented side effects induced by creatine monohydrate are weight gain; influence on insulin production; feedback inhibition of endogenous creatine synthesis; long-term damages on renal function. A major point that related to the quality of creatine monohydrate products is the amount of creatine ingested in relation to the amount of contaminants present. During the industrial production of creatine monohydrate from sarcosine and cyanamide, variable amounts of contaminants (dicyandiamide, dihydrotriazines, creatinine, ions) are generated and, thus, their tolerable concentrations (ppm) must be defined and made consumers known. Furthermore, because sarcosine could originate from bovine tissues, the risk of contamination with prion of bovine spongiform encephalopathy (BSE or mad-cow disease) can t be excluded. Thus, French authorities forbade the sale of products containing creatine. Creatine, as other nutritional factors, can be used either at supplementary or therapeutic levels as a function of the dose. Supplementary doses of nutritional factors usually are of the order of the daily turnover, while therapeutic ones are three or more times higher. In a subject of 70 kg with a total creatine pool of 120 g, the daily turnover is approximately of 2 g. Thus, in healthy subjects nourished with fat-rich, carbohydrate, protein-poor diet and participating in a daily recreational sport, the oral creatine monohydrate supplementation should be of the order of the daily turnover, i.e., less than 2.5-3 g per day, bringing the gastrointestinal absorption to account. In healthy athletes submitted daily to high-intensity strength or sprint training, the maximal oral creatine monohydrate supplementation should be of the order of two times the daily turnover, i.e., less than 5-6 g per day for less than two weeks, and the creatine monohydrate supplementation should be taken under appropriate medical supervision. The oral administration of more that 6 g per day of creatine monohydrate should be considered as a therapeutic intervention and should be prescribed by physicians only in the cases of suspected or proven deficiency, or in conditions of severe stress and/or injury. The incorporation of creatine into the medicinal product class is supported also by the use in pathological conditions, e.g., some mitochondrial cytopathies, the guanidinoacetate methyltransferase deficiency, etc. PMID:11317142

  6. 21 CFR 862.1215 - Creatine phosphokinase/creatine kinase or isoenzymes test system.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES CLINICAL CHEMISTRY AND CLINICAL TOXICOLOGY DEVICES Clinical Chemistry Test Systems § 862.1215 Creatine phosphokinase/creatine kinase or isoenzymes test...

  7. 21 CFR 862.1215 - Creatine phosphokinase/creatine kinase or isoenzymes test system.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES CLINICAL CHEMISTRY AND CLINICAL TOXICOLOGY DEVICES Clinical Chemistry Test Systems § 862.1215 Creatine phosphokinase/creatine kinase or isoenzymes test...

  8. 21 CFR 862.1215 - Creatine phosphokinase/creatine kinase or isoenzymes test system.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES CLINICAL CHEMISTRY AND CLINICAL TOXICOLOGY DEVICES Clinical Chemistry Test Systems § 862.1215 Creatine phosphokinase/creatine kinase or isoenzymes test...

  9. 21 CFR 862.1215 - Creatine phosphokinase/creatine kinase or isoenzymes test system.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES CLINICAL CHEMISTRY AND CLINICAL TOXICOLOGY DEVICES Clinical Chemistry Test Systems § 862.1215 Creatine phosphokinase/creatine kinase or isoenzymes test...

  10. 21 CFR 862.1215 - Creatine phosphokinase/creatine kinase or isoenzymes test system.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES CLINICAL CHEMISTRY AND CLINICAL TOXICOLOGY DEVICES Clinical Chemistry Test Systems § 862.1215 Creatine phosphokinase/creatine kinase or isoenzymes test...

  11. Creatine and caffeine in anaerobic and aerobic exercise: effects on physical performance and pharmacokinetic considerations.

    PubMed

    Vanakoski, J; Kosunen, V; Meririnne, E; Seppälä, T

    1998-05-01

    The pharmacokinetics and effects of creatine and caffeine administration on anaerobic and aerobic performance of 7 trained athletes were studied in a randomized, placebo-controlled, double-blind crossover design. The treatments were: placebo (PLA), a single oral dose (7 mg x kg(-1)) of caffeine (CAF), repeated oral doses (3 x 100 mg x kg(-1) x day(-1)) of creatine for 3 days (CRE), or the combination of caffeine and creatine (CAF + CRE) before physical exercise. In one session CAF was administered without exercise. Drug administration was followed by 3 repetitive 1-minute exercise bouts on a bicycle ergometer at maximal speed (anaerobic exercise) starting 70 min after drug administration. Anaerobic exercise was followed by 45 min of cycling at constant pedalling speed and workload (aerobic exercise). CRE and CAF, alone or in combination, did not improve maximal pedalling speed (rpm), maintenance of maximal speed (rpm) or total work output (kJ) during the 1 -minute bouts, when compared with PLA. In addition, no statistically significant differences in heart rate or blood lactate were observed between the treatments either during anaerobic or aerobic exercise bouts. Creatine was rapidly and efficiently absorbed, as reflected by plasma concentrations. The mean +/-SEM value for creatine Cmax was 1.22+/-0.14 mmol x l(-1), tmax 92+/-7 min and plasma half-life (t1/2beta) 172+/-21 min. Caffeine pharmacokinetics were not affected by concomitant administration of creatine or by physical exercise. In conclusion, neither maximal performance and subsequent recovery nor aerobic performance were enhanced by oral creatine supplementation in the study. PMID:9629989

  12. Lactate Test

    MedlinePlus

    ... services. Advertising & Sponsorship: Policy | Opportunities PLEASE NOTE: Your web browser does not have JavaScript enabled. Unless you enable Javascript , your ability ... CSF Lactate Formal name: Lactate Related tests: Blood Gases , Pyruvate, CSF Analysis , Comprehensive Metabolic Panel , Basic Metabolic Panel , Electrolytes , Emergency ...

  13. Creatine supplementation: exploring the role of the creatine kinase/phosphocreatine system in human muscle.

    PubMed

    Hespel, P; Eijnde, B O; Derave, W; Richter, E A

    2001-01-01

    The effect of oral creatine supplementation on high-intensity exercise performance has been extensively studied over the past ten years and its ergogenic potential in young healthy subjects is now well documented. Recently, research has shifted from performance evaluation towards elucidating the mechanisms underlying enhanced muscle functional capacity after creatine supplementation. In this review, we attempt to summarise recent advances in the understanding of potential mechanisms of action of creatine supplementation at the level of skeletal muscle cells. By increasing intracellular creatine content, oral creatine ingestion conceivably stimulates operation of the creatine kinase (CK)/phosphocreatine (PCr) system, which in turn facilitates muscle relaxation. Furthermore, evidence is accumulating to suggest that creatine supplementation can beneficially impact on muscle protein and glycogen synthesis. Thus, muscle hypertrophy and glycogen supercompensation are candidate factors to explain the ergogenic potential of creatine ingestion. Additional issues discussed in this review are the fibre-type specificity of muscle creatine metabolism, the identification of responders versus non-responders to creatine intake, and the scientific background concerning potential side effects of creatine supplementation. PMID:11897886

  14. Creatine biosynthesis and transport in health and disease.

    PubMed

    Joncquel-Chevalier Curt, Marie; Voicu, Pia-Manuela; Fontaine, Monique; Dessein, Anne-Frédérique; Porchet, Nicole; Mention-Mulliez, Karine; Dobbelaere, Dries; Soto-Ares, Gustavo; Cheillan, David; Vamecq, Joseph

    2015-12-01

    Creatine is physiologically provided equally by diet and by endogenous synthesis from arginine and glycine with successive involvements of arginine glycine amidinotransferase [AGAT] and guanidinoacetate methyl transferase [GAMT]. A specific plasma membrane transporter, creatine transporter [CRTR] (SLC6A8), further enables cells to incorporate creatine and through uptake of its precursor, guanidinoacetate, also directly contributes to creatine biosynthesis. Breakthrough in the role of creatine has arisen from studies on creatine deficiency disorders. Primary creatine disorders are inherited as autosomal recessive (mutations affecting GATM [for glycine-amidinotransferase, mitochondrial]) and GAMT genes) or X-linked (SLC6A8 gene) traits. They have highlighted the role of creatine in brain functions altered in patients (global developmental delay, intellectual disability, behavioral disorders). Creatine modulates GABAergic and glutamatergic cerebral pathways, presynaptic CRTR (SLC6A8) ensuring re-uptake of synaptic creatine. Secondary creatine disorders, addressing other genes, have stressed the extraordinary imbrication of creatine metabolism with many other cellular pathways. This high dependence on multiple pathways supports creatine as a cellular sensor, to cell methylation and energy status. Creatine biosynthesis consumes 40% of methyl groups produced as S-adenosylmethionine, and creatine uptake is controlled by AMP activated protein kinase, a ubiquitous sensor of energy depletion. Today, creatine is considered as a potential sensor of cell methylation and energy status, a neurotransmitter influencing key (GABAergic and glutamatergic) CNS neurotransmission, therapeutic agent with anaplerotic properties (towards creatine kinases [creatine-creatine phosphate cycle] and creatine neurotransmission), energetic and antioxidant compound (benefits in degenerative diseases through protection against energy depletion and oxidant species) with osmolyte behavior (retention of water by muscle). This review encompasses all these aspects by providing an illustrated metabolic account for brain and body creatine in health and disease, an algorithm to diagnose metabolic and gene bases of primary and secondary creatine deficiencies, and a metabolic exploration by (1)H-MRS assessment of cerebral creatine levels and response to therapeutic measures. PMID:26542286

  15. Effects of creatine supplementation on exercise performance.

    PubMed

    Demant, T W; Rhodes, E C

    1999-07-01

    While creatine has been known to man since 1835, when a French scientist reported finding this constitutent of meat, its presence in athletics as a performance enhancer is relatively new. Amid claims of increased power and strength, decreased performance time and increased muscle mass, creatine is being hailed as a true ergogenic aid. Creatinine is synthesised from the amino acids glycine, arginine and methionine in the kidneys, liver and pancreas, and is predominantly found in skeletal muscle, where it exists in 2 forms. Approximately 40% is in the free creatine form (Crfree), while the remaining 60% is in the phosphorylated form, creatine phosphate (CP). The daily turnover rate of approximately 2 g per day is equally met via exogenous intake and endogenous synthesis. Although creatine concentration (Cr) is greater in fast twitch muscle fibres, slow twitch fibres have a greater resynthesis capability due to their increased aerobic capacity. There appears to be no significant difference between males and females in Cr, and training does not appear to effect Cr. The 4 roles in which creatine is involved during performance are temporal energy buffering, spatial energy buffering, proton buffering and glycolysis regulation. Creatine supplementation of 20 g per day for at least 3 days has resulted in significant increases in total Cr for some individuals but not others, suggesting that there are 'responders' and 'nonresponders'. These increases in total concentration among responders is greatest in individuals who have the lowest initial total Cr, such as vegetarians. Increased concentrations of both Crfree and CP are believed to aid performance by providing more short term energy, as well as increase the rate of resynthesis during rest intervals. Creatine supplementation does not appear to aid endurance and incremental type exercises, and may even be detrimental. Studies investigating the effects of creatine supplementation on short term, high intensity exercises have reported equivocal results, with approximately equal numbers reporting significant and nonsignificant results. The only side effect associated with creatine supplementation appears to be a small increase in body mass, which is due to either water retention or increased protein synthesis. PMID:10461712

  16. Lactate metabolism in the fetal rabbit lung

    SciTech Connect

    Engle, M.J.; Brown, D.J.; Dooley, M.

    1986-05-01

    Lactate is frequently overlooked as a potential substrate for the fetal lung, even though it is present in the fetal circulation in concentrations as high as 8 mM. These high concentrations, coupled with the relatively low levels of glucose in the fetal blood, may indicate that lactate can substitute for glucose in pulmonary energy generation and phospholipid synthesis. A series of experiments was therefore undertaken in order to investigate the role of lactate in perinatal pulmonary development. Explants from 30 day gestation fetal rabbit lungs were incubated in Krebs-Ringer bicarbonate buffer supplemented with 3 mM (U-/sup 14/C)-glucose and varying levels of lactate. In the absence of medium lactate, fetal rabbit lung explants were capable of producing lactate at a rate of approximately 200 etamoles/mg protein/hour. The addition of lactate to the bathing medium immediately reduced net lactate production and above 4 mM, fetal rabbit lung explants became net utilizers of lactate. Media lactate concentrations of 2.5 mM, 5 mM and 10 mM also decreased glucose incorporation into total tissue disaturated phosphatidylcholine by approximately 20%, 35%, and 45%, respectively. Glucose incorporation into surfactant phosphatidylcholine was also reduced by approximately 50%, when lactate was present in the incubation medium at a concentration of 5 mM. Additional experiments also revealed that fetal lung lactate dehydrogenase activity was almost twice that found in the adult rabbit lung. These data indicate that lactate may be an important carbon source for the developing lung and could be a significant component in the manufacture of surfactant phosphatidylcholine during late gestation.

  17. Studies on the safety of creatine supplementation.

    PubMed

    Kim, Hyo Jeong; Kim, Chang Keun; Carpentier, A; Poortmans, Jacques R

    2011-05-01

    Doubtful allegations of adverse effects of creatine supplementation have been released through the press media and through scientific publications. In the present review we have tried to separate the wheat from the chaff by looking for the experimental evidence of any such claims. Anecdotal reports from athletes have appeared on muscle cramp and gastrointestinal complaints during creatine supplementation, but the incidence of these is limited and not necessarily linked to creatine itself. Despite several unproved allegations, liver (enzymes, urea) and kidneys (glomerular filtration urea and albumin excretion rates) show no change in functionality in healthy subjects supplemented with creatine, even during several months, in both young and older populations. The potential effects (production of heterocyclic amines) of mutagenicity and carcinogenicity induced by creatine supplementation have been claimed by a French Sanitary Agency (AFSSA), which might put consumers at risk. Even if there is a slight increase (within the normal range) of urinary methylamine and formaldehyde excretion after a heavy load of creatine (20 g/day) this is without effect on kidney function. The search for the excretion of heterocyclic amines remains a future task to definitively exclude the unproved allegation made by some national agencies. We advise that high-dose (>3-5 g/day) creatine supplementation should not be used by individuals with pre-existing renal disease or those with a potential risk for renal dysfunction (diabetes, hypertension, reduced glomerular filtration rate). A pre-supplementation investigation of kidney function might be considered for reasons of safety, but in normal healthy subjects appears unnecessary. PMID:21399917

  18. Inhibition of lactate glucogneogenesis in rat kidney by dichloroacetate.

    PubMed Central

    Lacey, J H; Randle, P J

    1978-01-01

    1. Sodium dichloroacetate (1mM) inhibited glucose production from L-lactate in kidney-cortex slices from fed, starved or alloxan-diabetic rates. In general gluconeogenesis from other substrates was no inhibited. 2. Sodium dichloracetate inhibited glucose production from L-lactate but no from pyruvate in perfused isolated kidneys from normal or alloxan-diabetic rats. 3. Sodium dichloroacetate is an inhibitor of the pyruvate dehydrogenase kinase reaction and it effected conversion of pyruvate dehydrogenase into its its active (dephosphorylated) form in kidney in vivo. In general, pyruvate dehydrogenase was mainly in the active form in kidneys perfused or incubated with L-lactate and the inhibitory effect of dichloroacetate on glucose production was not dependent on activation of pyruvate dehydrogenase. 4. Balance data from kidney slices showed that dichloroacetate inhibits lactate uptake, glucose and pyruvate production from lactate, but no oxidation of lactate. 5. The mechanism of this effect of dichloroactetate on glucose production from lactate has not been fully defined, but evidence suggests that it may involve a fall in tissue pyruvate concentration and inhibition of pyruvate carboxylation. PMID:646800

  19. Glycolysis and the significance of lactate in traumatic brain injury

    PubMed Central

    Carpenter, Keri L. H.; Jalloh, Ibrahim; Hutchinson, Peter J.

    2015-01-01

    In traumatic brain injury (TBI) patients, elevation of the brain extracellular lactate concentration and the lactate/pyruvate ratio are well-recognized, and are associated statistically with unfavorable clinical outcome. Brain extracellular lactate was conventionally regarded as a waste product of glucose, when glucose is metabolized via glycolysis (Embden-Meyerhof-Parnas pathway) to pyruvate, followed by conversion to lactate by the action of lactate dehydrogenase, and export of lactate into the extracellular fluid. In TBI, glycolytic lactate is ascribed to hypoxia or mitochondrial dysfunction, although the precise nature of the latter is incompletely understood. Seemingly in contrast to lactate's association with unfavorable outcome is a growing body of evidence that lactate can be beneficial. The idea that the brain can utilize lactate by feeding into the tricarboxylic acid (TCA) cycle of neurons, first published two decades ago, has become known as the astrocyte-neuron lactate shuttle hypothesis. Direct evidence of brain utilization of lactate was first obtained 5 years ago in a cerebral microdialysis study in TBI patients, where administration of 13C-labeled lactate via the microdialysis catheter and simultaneous collection of the emerging microdialysates, with 13C NMR analysis, revealed 13C labeling in glutamine consistent with lactate utilization via the TCA cycle. This suggests that where neurons are too damaged to utilize the lactate produced from glucose by astrocytes, i.e., uncoupling of neuronal and glial metabolism, high extracellular levels of lactate would accumulate, explaining the association between high lactate and poor outcome. Recently, an intravenous exogenous lactate supplementation study in TBI patients revealed evidence for a beneficial effect judged by surrogate endpoints. Here we review the current state of knowledge about glycolysis and lactate in TBI, how it can be measured in patients, and whether it can be modulated to achieve better clinical outcome. PMID:25904838

  20. Evaluation of NAD(P)-Dependent Dehydrogenase Activities in Neutrophilic Granulocytes by the Bioluminescent Method.

    PubMed

    Savchenko, A A

    2015-09-01

    Bioluminescent method for measurements of the neutrophilic NAD(P)-dependent dehydrogenases (lactate dehydrogenase, NAD-dependent malate dehydrogenase, NADP-dependent decarboxylating malate dehydrogenase, NAD-dependent isocitrate dehydrogenase, and glucose- 6-phosphate dehydrogenase) is developed. The sensitivity of the method allows minimization of the volume of biological material for measurements to 104 neutrophils per analysis. The method is tried in patients with diffuse purulent peritonitis. Low levels of NADPH synthesis enzymes and high levels of enzymes determining the substrate flow by the Krebs cycle found in these patients can lead to attenuation of functional activity of cells. PMID:26468025

  1. Creatine metabolism and psychiatric disorders: Does creatine supplementation have therapeutic value?

    PubMed Central

    Allen, Patricia J.

    2012-01-01

    Athletes, body builders, and military personnel use dietary creatine as an ergogenic aid to boost physical performance in sports involving short bursts of high-intensity muscle activity. Lesser known is the essential role creatine, a natural regulator of energy homeostasis, plays in brain function and development. Creatine supplementation has shown promise as a safe, effective, and tolerable adjunct to medication for the treatment of brain-related disorders linked with dysfunctional energy metabolism, such as Huntington’s Disease and Parkinson’s Disease. Impairments in creatine metabolism have also been implicated in the pathogenesis of psychiatric disorders, leaving clinicians, researchers and patients alike wondering if dietary creatine has therapeutic value for treating mental illness. The present review summarizes the neurobiology of the creatine-phosphocreatine circuit and its relation to psychological stress, schizophrenia, mood and anxiety disorders. While present knowledge of the role of creatine in cognitive and emotional processing is in its infancy, further research on this endogenous metabolite has the potential to advance our understanding of the biological bases of psychopathology and improve current therapeutic strategies. PMID:22465051

  2. Lactic acid-producing yeast cells having nonfunctional L- or D-lactate:ferricytochrome C oxidoreductase cells

    DOEpatents

    Miller, Matthew; Suominen, Pirkko; Aristidou, Aristos; Hause, Benjamin Matthew; Van Hoek, Pim; Dundon, Catherine Asleson

    2012-03-20

    Yeast cells having an exogenous lactate dehydrogenase gene ae modified by reducing L- or D-lactate:ferricytochrome c oxidoreductase activity in the cell. This leads to reduced consumption of lactate by the cell and can increase overall lactate yields in a fermentation process. Cells having the reduced L- or D-lactate:ferricytochrome c oxidoreductase activity can be screened for by resistance to organic acids such as lactic or glycolic acid.

  3. Effects of Combined Creatine Plus Fenugreek Extract vs. Creatine Plus Carbohydrate Supplementation on Resistance Training Adaptations

    PubMed Central

    Taylor, Lem; Poole, Chris; Pena, Earnest; Lewing, Morgan; Kreider, Richard; Foster, Cliffa; Wilborn, Colin

    2011-01-01

    The purpose of this study was to evaluate the effects of combined creatine and fenugreek extract supplementation on strength and body composition. Forty- seven resistance trained men were matched according to body weight to ingest either 70 g of a dextrose placebo (PL), 5 g creatine/70 g of dextrose (CRD) or 3.5 g creatine/900 mg fenugreek extract (CRF) and participate in a 4-d/wk periodized resistance-training program for 8-weeks. At 0, 4, and 8-weeks, subjects were tested on body composition, muscular strength and endurance, and anaerobic capacity. Statistical analyses utilized a separate 3X3 (condition [PL vs. CRD vs. CRF] x time [T1 vs. T2 vs. T3]) ANOVAs with repeated measures for all criterion variables (p ≤ 0.05). No group x time interaction effects or main effects (p > 0.05) were observed for any measures of body composition. CRF group showed significant increases in lean mass at T2 (p = 0.001) and T3 (p = 0.001). Bench press 1RM increased in PL group (p = 0.050) from T1-T3 and in CRD from T1-T2 (p = 0. 001) while remaining significant at T3 (p < 0.001). CRF group showed a significant increase in bench press 1RM from T1-T2 (p < 0.001), and also increased from T2-T3 (p = 0.032). Leg press 1RM significantly increased at all time points for PL, CRD, and CRF groups (p < 0.05). No additional between or within group changes were observed for any performance variables and serum clinical safety profiles (p > 0.05). In conclusion, creatine plus fenugreek extract supplementation had a significant impact on upper body strength and body composition as effectively as the combination of 5g of creatine with 70g of dextrose. Thus, the use of fenugreek with creatine supplementation may be an effective means for enhancing creatine uptake while eliminating the need for excessive amounts of simple carbohydrates. Key points Fenugreek plus creatine supplementation may be a new means of increasing creatine uptake. Creatine plus fenugreek seems to be just as effective as the classic creatine plus carbohydrate ingestion in terms of stimulating training adaptations. This is the first study to our knowledge that has combined fenugreek with creatine supplementation in conjunction with a resistance training program. PMID:24149869

  4. Genetics Home Reference: X-linked creatine deficiency

    MedlinePlus

    ... Deficiencies Children Living with Inherited Metabolic Diseases The Arc: for People with Intellectual and Developmental Disabilities Gene Reviews (1 link) Creatine Deficiency Syndromes Genetic Testing Registry (1 link) Creatine deficiency, X- ...

  5. Whole body creatine and protein kinetics in healthy men and women: effects of creatine and amino acid supplementation.

    PubMed

    Kalhan, Satish C; Gruca, Lourdes; Marczewski, Susan; Bennett, Carole; Kummitha, China

    2016-03-01

    Creatine kinetics were measured in young healthy subjects, eight males and seven females, age 20-30 years, after an overnight fast on creatine-free diet. Whole body turnover of glycine and its appearance in creatine was quantified using [1-(13)C] glycine and the rate of protein turnover was quantified using L-ring [(2)H5] phenylalanine. The creatine pool size was estimated by the dilution of a bolus [C(2)H3] creatine. Studies were repeated following a five days supplement creatine 21 g.day(-1) and following supplement amino acids 14.3 g day(-1). Creatine caused a ten-fold increase in the plasma concentration of creatine and a 50 % decrease in the concentration of guanidinoacetic acid. Plasma amino acids profile showed a significant decrease in glycine, glutamine, and taurine and a significant increase in citrulline, valine, lysine, and cysteine. There was a significant decrease in the rate of appearance of glycine, suggesting a decrease in de-novo synthesis (p = 0.006). The fractional and absolute rate of synthesis of creatine was significantly decreased by supplemental creatine. Amino acid supplement had no impact on any of the parameters. This is the first detailed analysis of creatine kinetics and the effects of creatine supplement in healthy young men and women. These methods can be applied for the analysis of creatine kinetics in different physiological states. PMID:26480831

  6. The primary pathway for lactate oxidation in Desulfovibrio vulgaris

    PubMed Central

    Vita, Nicolas; Valette, Odile; Brasseur, Gaël; Lignon, Sabrina; Denis, Yann; Ansaldi, Mireille; Dolla, Alain; Pieulle, Laetitia

    2015-01-01

    The ability to respire sulfate linked to lactate oxidation is a key metabolic signature of the Desulfovibrio genus. Lactate oxidation by these incomplete oxidizers generates reductants through lactate dehydrogenase (LDH) and pyruvate-ferredoxin oxidoreductase (PFOR), with the latter catalyzing pyruvate conversion into acetyl-CoA. Acetyl-CoA is the source of substrate-level phosphorylation through the production of ATP. Here, we show that these crucial steps are performed by enzymes encoded by a nonacistronic transcriptional unit named now as operon luo (for lactate utilization operon). Using a combination of genetic and biochemical techniques, we assigned a physiological role to the operon genes DVU3027-28 and DVU3032-33. The growth of mutant Δ26-28 was highly disrupted on D-lactate, whereas the growth of mutant Δ32-33 was slower on L-lactate, which could be related to a decrease in the activity of D-lactate or L-lactate oxidase in the corresponding mutants. The DVU3027-28 and DVU3032-33 genes thus encode functional D-LDH and L-LDH enzymes, respectively. Scanning of the genome for lactate utilization revealed several lactate permease and dehydrogenase homologs. However, transcriptional compensation was not observed in any of the mutants except for lactate permease. Although there is a high degree of redundancy for lactate oxidase, it is not functionally efficient in LDH mutants. This result could be related to the identification of several operon enzymes, including LDHs, in the PFOR activity bands, suggesting the occurrence of a lactate-oxidizing supermolecular structure that can optimize the performance of lactate utilization in Desulfovibrio species. PMID:26167158

  7. The primary pathway for lactate oxidation in Desulfovibrio vulgaris.

    PubMed

    Vita, Nicolas; Valette, Odile; Brasseur, Gaël; Lignon, Sabrina; Denis, Yann; Ansaldi, Mireille; Dolla, Alain; Pieulle, Laetitia

    2015-01-01

    The ability to respire sulfate linked to lactate oxidation is a key metabolic signature of the Desulfovibrio genus. Lactate oxidation by these incomplete oxidizers generates reductants through lactate dehydrogenase (LDH) and pyruvate-ferredoxin oxidoreductase (PFOR), with the latter catalyzing pyruvate conversion into acetyl-CoA. Acetyl-CoA is the source of substrate-level phosphorylation through the production of ATP. Here, we show that these crucial steps are performed by enzymes encoded by a nonacistronic transcriptional unit named now as operon luo (for lactate utilization operon). Using a combination of genetic and biochemical techniques, we assigned a physiological role to the operon genes DVU3027-28 and DVU3032-33. The growth of mutant Δ26-28 was highly disrupted on D-lactate, whereas the growth of mutant Δ32-33 was slower on L-lactate, which could be related to a decrease in the activity of D-lactate or L-lactate oxidase in the corresponding mutants. The DVU3027-28 and DVU3032-33 genes thus encode functional D-LDH and L-LDH enzymes, respectively. Scanning of the genome for lactate utilization revealed several lactate permease and dehydrogenase homologs. However, transcriptional compensation was not observed in any of the mutants except for lactate permease. Although there is a high degree of redundancy for lactate oxidase, it is not functionally efficient in LDH mutants. This result could be related to the identification of several operon enzymes, including LDHs, in the PFOR activity bands, suggesting the occurrence of a lactate-oxidizing supermolecular structure that can optimize the performance of lactate utilization in Desulfovibrio species. PMID:26167158

  8. Creatine and the Male Adolescent Athlete

    ERIC Educational Resources Information Center

    Schumaker, Shauna; Eyers, Christina; Cappaert, Thomas

    2012-01-01

    As the level of competition in youth sports increases, so does athletes' vulnerability to experimenting with performance-enhancing aids (PEAs) at alarmingly young ages. One of the more commonly used PEAs is a supplement called creatine, which has the ability to generate muscular energy, allowing athletes to train at higher intensities for longer…

  9. Creatine and the Male Adolescent Athlete

    ERIC Educational Resources Information Center

    Schumaker, Shauna; Eyers, Christina; Cappaert, Thomas

    2012-01-01

    As the level of competition in youth sports increases, so does athletes' vulnerability to experimenting with performance-enhancing aids (PEAs) at alarmingly young ages. One of the more commonly used PEAs is a supplement called creatine, which has the ability to generate muscular energy, allowing athletes to train at higher intensities for longer

  10. 21 CFR 862.1210 - Creatine test system.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Creatine test system. 862.1210 Section 862.1210....1210 Creatine test system. (a) Identification. A creatine test system is a device intended to measure... and endocrine disorders including hyperthyroidism. (b) Classification. Class I (general controls)....

  11. 21 CFR 862.1210 - Creatine test system.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Creatine test system. 862.1210 Section 862.1210....1210 Creatine test system. (a) Identification. A creatine test system is a device intended to measure... and endocrine disorders including hyperthyroidism. (b) Classification. Class I (general controls)....

  12. 21 CFR 862.1210 - Creatine test system.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Creatine test system. 862.1210 Section 862.1210....1210 Creatine test system. (a) Identification. A creatine test system is a device intended to measure... and endocrine disorders including hyperthyroidism. (b) Classification. Class I (general controls)....

  13. 21 CFR 862.1210 - Creatine test system.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Creatine test system. 862.1210 Section 862.1210....1210 Creatine test system. (a) Identification. A creatine test system is a device intended to measure... and endocrine disorders including hyperthyroidism. (b) Classification. Class I (general controls)....

  14. 21 CFR 862.1210 - Creatine test system.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Creatine test system. 862.1210 Section 862.1210....1210 Creatine test system. (a) Identification. A creatine test system is a device intended to measure... and endocrine disorders including hyperthyroidism. (b) Classification. Class I (general controls)....

  15. Determination of creatine in commercial creatine powder with new potentiometric and amperometric biosensors.

    PubMed

    Karakuş, Emine; Erden, Pinar Esra; Pekyardimci, Sule; Kiliç, Esma

    2006-01-01

    New potentiometric and amperometric biosensors were developed for the determination of creatine. The potentiometric creatine biosensor was prepared by immobilizing urease and creatinase on poly(vinylchloride) (PVC) ammonium membrane electrode containing palmitic acid prepared by using nonactine as an ammonium-ionophore. The linear working range of the biosensor was 1.0 x 10(-5) - 1.0 x 10(-3) M and the response time was about 60 s. The optimum pH, temperature, and buffer concentration were found to be 7.0, 20 degrees C, and 5 mM, respectively. The slope of the electrode was 49.2 mV/p[creatine]. The storage stabilization of the biosensor was investigated and 40-45% decrease in the response was detected after 2 months. The amperometric creatine biosensor was prepared by immobilizing creatinase (CI) and sarcosine oxidase (SO) in a poly(vinylferrocenium) matrix onto the surface of a platinum working electrode by crosslinking with glutaraldehyde (GA) and bovine serum albumine (BSA). Determination of creatine was performed by the oxidation of enzymatically generated H2O2 at +0.7 V vs. Ag/AgCl. The linear working range of the biosensor was 2.0 x 10(-5) - 3.2 x 10(-4) M and the response time was about 50 s. The effects of pH, temperature, enzyme ratio and buffer concentration were investigated and optimum parameters were found to be 7.5, 37 degrees C, 2.5:1 (CI:SO) and 0.05 M, respectively. The determination of creatine in commercial creatine powder was successfully carried out with these creatine biosensors by using the standard addition and calibration curve methods. The results were in good agreement with those obtained from Jaffé method at 95% confidence level. PMID:16809134

  16. Effect of manual lymph drainage on removal of blood lactate after submaximal exercise.

    PubMed

    Bakar, Yesim; Coknaz, Hakkı; Karlı, Ümid; Semsek, Önder; Serın, Erdinc; Pala, Ömer Osman

    2015-11-01

    [Purpose] It has been well-established that exercise-induced muscle damage occurs following intense exercise. Massage is commonly used to manage muscle damage resulting from exercise. However the effect of massage after exercise is still not clear. The purpose of this study was to examine the effect of manual lymph drainage on muscle damage and on the removal of blood lactate following submaximal exercise (SE), as part of a solution to the challenging problem in sports medicine of muscular recovery after exercise. [Subjects and Methods] Eighteen healthy male students, with moderate exercise training, were randomly assigned to either receive manual lymph drainage (MLD) or serve as controls. Both groups were subjected to a graded exercise test, performed on a treadmill ergometer, to determine each subject's individual anaerobic threshold (IAT). Seven days later, all subjects were made to run for 30 minutes on the same treadmill ergometer, at a running speed equivalent to the IAT. One group received MLD treatment, while the control subjects received no treatment. [Results] Following an increase immediately after exercise, lactic acid (LA) and lactate dehydrogenase (LDH) serum levels dropped rapidly and significantly at the end of MLD application and two hours after SE in the subjects receiving MLD. The course of creatine kinase (CK) and myoglobin levels was comparable, and with myoglobin showing a significant difference at 2 h after SE, and CK at 24 h after SE. [Conclusion] Manual lymph drainage after SE correlated with a more rapid fall in LA and of the muscular enzymes of LDH, CK and myoglobin, and may have resulted in an improvement in the regenerative processes elicted by structural damage to the muscle cells. PMID:26696704

  17. Effect of manual lymph drainage on removal of blood lactate after submaximal exercise

    PubMed Central

    Bakar, Yesim; Coknaz, Hakkı; Karlı, Ümid; Semsek, Önder; Serın, Erdinc; Pala, Ömer Osman

    2015-01-01

    [Purpose] It has been well-established that exercise-induced muscle damage occurs following intense exercise. Massage is commonly used to manage muscle damage resulting from exercise. However the effect of massage after exercise is still not clear. The purpose of this study was to examine the effect of manual lymph drainage on muscle damage and on the removal of blood lactate following submaximal exercise (SE), as part of a solution to the challenging problem in sports medicine of muscular recovery after exercise. [Subjects and Methods] Eighteen healthy male students, with moderate exercise training, were randomly assigned to either receive manual lymph drainage (MLD) or serve as controls. Both groups were subjected to a graded exercise test, performed on a treadmill ergometer, to determine each subject’s individual anaerobic threshold (IAT). Seven days later, all subjects were made to run for 30 minutes on the same treadmill ergometer, at a running speed equivalent to the IAT. One group received MLD treatment, while the control subjects received no treatment. [Results] Following an increase immediately after exercise, lactic acid (LA) and lactate dehydrogenase (LDH) serum levels dropped rapidly and significantly at the end of MLD application and two hours after SE in the subjects receiving MLD. The course of creatine kinase (CK) and myoglobin levels was comparable, and with myoglobin showing a significant difference at 2 h after SE, and CK at 24 h after SE. [Conclusion] Manual lymph drainage after SE correlated with a more rapid fall in LA and of the muscular enzymes of LDH, CK and myoglobin, and may have resulted in an improvement in the regenerative processes elicted by structural damage to the muscle cells. PMID:26696704

  18. Creatine supplementation improves the anaerobic performance of elite junior fin swimmers.

    PubMed

    Juhász, Imre; Györe, I; Csende, Zs; Rácz, L; Tihanyi, J

    2009-09-01

    The objective of this study was to determine whether creatine supplementation (CrS) could improve mechanical power output, and swimming performance in highly trained junior competitive fin swimmers. Sixteen male fin swimmers (age:15.9+/-1.6 years) were randomly and evenly assigned to either a creatine (CR, 4x5 g/day creatine monohydrate for 5 days) or placebo group (P, same dose of a dextrose-ascorbic acid placebo) in a double-blind research. Before and after CrS the average power output was determined by a Bosco-test and the swimming time was measured in two maximal 100 m fin swims. After five days of CrS the average power of one minute continuous rebound jumps increased by 20.2%. The lactate concentration was significantly less after 5 minutes restitution at the second measurement in both groups. The swimming time was significantly reduced in both first (pre: 50.69+/-1.41 s; post: 48.86+/-1.34 s) and second (pre: 50.39+/-1.38 s; post: 48.53+/-1.35 s) sessions of swimming in CR group, but remained almost unchanged in the P group.The results of this study indicate that five day Cr supplementation enhances the dynamic strength and may increase anaerobic metabolism in the lower extremity muscles, and improves performance in consecutive maximal swims in highly trained adolescent fin swimmers. PMID:19706374

  19. Effect of creatine, creatinine, and creatine ethyl ester on TLR expression in macrophages

    PubMed Central

    Leland, Korey M.; McDonald, Thomas L.; Drescher, Kristen M.

    2011-01-01

    Despite the widespread availability and use of dietary supplements, minimal work has been performed to assess the potential dangers many of these supplements may have on the host’s well-being, in particular the host’s ability to respond to infection. One supplement extensively used by both adolescents and adults is creatine. Using Real-time PCR, we examined the impact of short-term exposure of a mouse macrophage cell line (RAW 264.7 cells) to two readily available forms of creatine used in supplements – creatine monohydrate (CR) and creatine ethyl ester (CEE) as well as the end product of creatine metabolism, creatinine (CRN), on expression of toll-like receptor-2 (TLR-2), TLR-3, TLR-4, and TLR-7. CR down-regulated TLR-2, TLR-3, TLR-4 and TLR-7 mRNA levels in RAW cells. Similar results were observed following exposure of RAW cells to CRN. Conversely CEE appears to possess immunostimulatory properties and increases expression of TLR-2, TLR-3, TLR-4, and TLR-7 in RAW cells. These data are supported by immunostaining using antibodies specific for the individual TLRs before and after exposure of RAW cells to CR, CRN, or CEE. To extend these findings, we isolated murine splenocytes and exposed the cells to CR, CEE, or CRN for 24 hours and performed immunofluorescent staining for TLR-2, TLR-3, TLR-4 and TLR-7. The results obtained from this study with primary splenocytes were consistent with the studies using RAW cells. Together, these data suggest that creatine and creatine derivatives may impact the ability of immune cells to sense a wide array of viral and bacterial pathogens. Of great interest, CRN - largely considered to be a waste product of the argenine biosynthesis pathway may also have immunosuppressive properties similar to those of CR. PMID:21575742

  20. Maternal dietary creatine supplementation does not alter the capacity for creatine synthesis in the newborn spiny mouse.

    PubMed

    Dickinson, Hayley; Ireland, Zoe J; Larosa, Domenic A; O'Connell, Bree A; Ellery, Stacey; Snow, Rod; Walker, David W

    2013-09-01

    We have previously reported that maternal creatine supplementation protects the neonate from hypoxic injury. Here, we investigated whether maternal creatine supplementation altered expression of the creatine synthesis enzymes (arginine:glycine amidinotransferase [AGAT], guanidinoaceteate methyltransferase [GAMT]) and the creatine transporter (solute carrier family 6 [neurotransmitter transporter, creatine] member 8: SLC6A8) in the term offspring. Pregnant spiny mice were fed a 5% creatine monohydrate diet from midgestation (day 20) to term (39 days). Placentas and neonatal kidney, liver, heart, and brain collected at 24 hours of age underwent quantitative polymerase chain reaction and Western blot analysis. Maternal creatine had no effect on the expression of AGAT and GAMT in neonatal kidney and liver, but mRNA expression of AGAT in brain tissues was significantly decreased in both male and female neonates born to mothers who were fed the creatine diet. SLC6A8 expression was not affected by maternal dietary creatine loading in any tissues. Maternal dietary creatine supplementation from midgestation in the spiny mouse did not alter the capacity for creatine synthesis or transport. PMID:23427185

  1. Comprehensive review on lactate metabolism in human health.

    PubMed

    Adeva-Andany, M; López-Ojén, M; Funcasta-Calderón, R; Ameneiros-Rodríguez, E; Donapetry-García, C; Vila-Altesor, M; Rodríguez-Seijas, J

    2014-07-01

    Metabolic pathways involved in lactate metabolism are important to understand the physiological response to exercise and the pathogenesis of prevalent diseases such as diabetes and cancer. Monocarboxylate transporters are being investigated as potential targets for diagnosis and therapy of these and other disorders. Glucose and alanine produce pyruvate which is reduced to lactate by lactate dehydrogenase in the cytoplasm without oxygen consumption. Lactate removal takes place via its oxidation to pyruvate by lactate dehydrogenase. Pyruvate may be either oxidized to carbon dioxide producing energy or transformed into glucose. Pyruvate oxidation requires oxygen supply and the cooperation of pyruvate dehydrogenase, the tricarboxylic acid cycle, and the mitochondrial respiratory chain. Enzymes of the gluconeogenesis pathway sequentially convert pyruvate into glucose. Congenital or acquired deficiency on gluconeogenesis or pyruvate oxidation, including tissue hypoxia, may induce lactate accumulation. Both obese individuals and patients with diabetes show elevated plasma lactate concentration compared to healthy subjects, but there is no conclusive evidence of hyperlactatemia causing insulin resistance. Available evidence suggests an association between defective mitochondrial oxidative capacity in the pancreatic β-cells and diminished insulin secretion that may trigger the development of diabetes in patients already affected with insulin resistance. Several mutations in the mitochondrial DNA are associated with diabetes mellitus, although the pathogenesis remains unsettled. Mitochondrial DNA mutations have been detected in a number of human cancers. d-lactate is a lactate enantiomer normally formed during glycolysis. Excess d-lactate is generated in diabetes, particularly during diabetic ketoacidosis. d-lactic acidosis is typically associated with small bowel resection. PMID:24929216

  2. Cerebral creatine deficiency syndromes: clinical aspects, treatment and pathophysiology.

    PubMed

    Stockler, Sylvia; Schutz, Peter W; Salomons, Gajja S

    2007-01-01

    Cerebral creatine deficiency syndromes (CCDSs) are a group of inborn errors of creatine metabolism comprising two autosomal recessive disorders that affect the biosynthesis of creatine--i.e. arginine:glycine amidinotransferase deficiency (AGAT; MIM 602360) and guanidinoacetate methyltransferase deficiency (GAMT; MIM 601240)--and an X-linked defect that affects the creatine transporter, SLC6A8 deficiency (SLC6A8; MIM 300036). The biochemical hallmarks of these disorders include cerebral creatine deficiency as detected in vivo by 1H magnetic resonance spectroscopy (MRS) of the brain, and specific disturbances in metabolites of creatine metabolism in body fluids. In urine and plasma, abnormal guanidinoacetic acid (GAA) levels are found in AGAT deficiency (reduced GAA) and in GAMT deficiency (increased GAA). In urine of males with SLC6A8 deficiency, an increased creatine/creatinine ratio is detected. The common clinical presentation in CCDS includes mental retardation, expressive speech and language delay, autistic like behaviour and epilepsy. Treatment of the creatine biosynthesis defects has yielded clinical improvement, while for creatine transporter deficiency, successful treatment strategies still need to be discovered. CCDSs may be responsible for a considerable fraction of children and adults affected with mental retardation of unknown etiology. Thus, screening for this group of disorders should be included in the differential diagnosis of this population. In this review, also the importance of CCDSs for the unravelling of the (patho)physiology of cerebral creatine metabolism is discussed. PMID:18652076

  3. Disturbed energy metabolism and muscular dystrophy caused by pure creatine deficiency are reversible by creatine intake

    PubMed Central

    Nabuurs, C I; Choe, C U; Veltien, A; Kan, H E; van Loon, L J C; Rodenburg, R J T; Matschke, J; Wieringa, B; Kemp, G J; Isbrandt, D; Heerschap, A

    2013-01-01

    Creatine (Cr) plays an important role in muscle energy homeostasis by its participation in the ATP–phosphocreatine phosphoryl exchange reaction mediated by creatine kinase. Given that the consequences of Cr depletion are incompletely understood, we assessed the morphological, metabolic and functional consequences of systemic depletion on skeletal muscle in a mouse model with deficiency of l-arginine:glycine amidinotransferase (AGAT−/−), which catalyses the first step of Cr biosynthesis. In vivo magnetic resonance spectroscopy showed a near-complete absence of Cr and phosphocreatine in resting hindlimb muscle of AGAT−/− mice. Compared with wild-type, the inorganic phosphate/β-ATP ratio was increased fourfold, while ATP levels were reduced by nearly half. Activities of proton-pumping respiratory chain enzymes were reduced, whereas F1F0-ATPase activity and overall mitochondrial content were increased. The Cr-deficient AGAT−/− mice had a reduced grip strength and suffered from severe muscle atrophy. Electron microscopy revealed increased amounts of intramyocellular lipid droplets and crystal formation within mitochondria of AGAT−/− muscle fibres. Ischaemia resulted in exacerbation of the decrease of pH and increased glycolytic ATP synthesis. Oral Cr administration led to rapid accumulation in skeletal muscle (faster than in brain) and reversed all the muscle abnormalities, revealing that the condition of the AGAT−/− mice can be switched between Cr deficient and normal simply by dietary manipulation. Systemic creatine depletion results in mitochondrial dysfunction and intracellular energy deficiency, as well as structural and physiological abnormalities. The consequences of AGAT deficiency are more pronounced than those of muscle-specific creatine kinase deficiency, which suggests a multifaceted involvement of creatine in muscle energy homeostasis in addition to its role in the phosphocreatine–creatine kinase system. PMID:23129796

  4. Efficient Production of Pyruvate from DL-Lactate by the Lactate-Utilizing Strain Pseudomonas stutzeri SDM

    PubMed Central

    Gao, Chao; Qiu, Jianhua; Ma, Cuiqing; Xu, Ping

    2012-01-01

    Background The platform chemical lactate is currently produced mainly through the fermentation of sugars presented in biomass. Besides the synthesis of biodegradable polylactate, lactate is also viewed as a feedstock for the green chemistry of the future. Pyruvate, another important platform chemical, can be produced from lactate through biocatalysis. Methodology/Principal Findings It was established that whole cells of Pseudomonas stutzeri SDM catalyze lactate oxidation with lactate-induced NAD-independent lactate dehydrogenases (iLDHs) through the inherent electron transfer chain. Unlike the lactate oxidation processes observed in previous reports, the mechanism underlying lactate oxidation described in the present study excluded the costliness of the cofactor regeneration step and production of the byproduct hydrogen peroxide. Conclusions/Significance Biocatalysis conditions were optimized by using the cheap dl-lactate as the substrate and whole cells of the lactate-utilizing P. stutzeri SDM as catalyst. Under optimal conditions, the biocatalytic process produced pyruvate at a high concentration (48.4 g l−1) and a high yield (98%). The bioconversion system provides a promising alternative for the green production of pyruvate. PMID:22792404

  5. Assay of creatine kinase in microtiter plates using thio-NAD to allow monitoring at 405 nM.

    PubMed

    Florini, J R

    1989-11-01

    An assay system for creatine kinase using microtiter plates and a plate reader that records absorbancies at 405 nM has been devised. The system is an adaptation of well-established assays that couple creatine kinase with the reactions catalyzed by hexokinase and glucose-6-phosphate dehydrogenase (G6PDH), to give a measurable increase in reduced pyridine nucleotide quantitated by absorbance at 340 nM. Two features of this system are modified for reading at 405 nM: (i) The thioamido derivative of NAD is used because its reduced form exhibits a substantial increase in absorbance at 405 nM, the most commonly available wavelength on microplate readers; and (ii) glucose-6-phosphate dehydrogenase from Leuconostoc mesenteroides is used because it can reduce either NAD or NADP (unlike most other G6PDH enzymes, which require NADP), thus making it unnecessary to use the more expensive thio-NADP. The rate of thio-NAD reduction is linear with enzyme concentration and time over a 20-fold range of concentrations of purified creatine kinase, and the assay also works well with myogenic cells allowed to grow and differentiate in the 96-well plate in which the assay is performed. This system offers considerable savings in cells, time, and material in studies of muscle cell differentiation, for which creatine kinase levels are frequently measured. It also provides a potential method for the convenient and economical measurement of activities of many other enzymes that can be coupled to reduction of thio-NAD. PMID:2610356

  6. Serum creatine kinase in marathon runners.

    PubMed

    Haibach, H; Hosler, M W

    1985-01-15

    Serum creatine phosphokinase (CK) and CK-MB activity were determined in 21 trained runners participating in a marathon race (42.2 km). Enzyme activities immediately after the race increased two to three times compared with activities before the race. The greatest increases were found in the slowest runners, suggesting greater skeletal muscular trauma in the least trained or fit. As these are likely to include the older athletes who are also more likely to suffer acute myocardial injury during strenuous exercise, our findings assume special import in the interpretation of increased CK and CK-MB serum activities of older athletes. PMID:3967735

  7. Creatine phosphokinase in rat mast cells.

    PubMed Central

    Magro, A M

    1980-01-01

    The soluble cytoplasmic fraction of an homogenate from peritoneal rat mast cells, demonstrated a considerable amount of catalytic activity which promotes the transfer of phosphate from creatine phosphate to ADP. The plasma membrane, mitochondrial and microsomal fractions show negligible amounts of the catalyst. Enzyme activity is maximal at 37 degrees showing little activity below 17 degrees or above 45 degrees. The enzyme is strongly Mg2+-dependent, whereas it is only slightly activated by Ca2+. pH values between 7 and 8 are optimal and the enzyme is irreversibly inactivated below pH 4. The overall behaviour of the catalyst indicates it to be a creatine phosphokinase (CPK), an enzyme considered important to muscle and nerve tissues. The CPK is probably not encapsulated within the mast cells' perigranular membranes and is retained in the soluble cytoplasm during exocytosis. The possible role of CPK, as to whether it is assisting in maintaining proper levels of intracellular ATP during exocytosis, and/or whether it is associated with components of the mast cells' contractile apparatus, is discussed. PMID:6160090

  8. Stringency of substrate specificity of Escherichia coli malate dehydrogenase.

    SciTech Connect

    Boernke, W. E.; Millard, C. S.; Stevens, P. W.; Kakar, S. N.; Stevens, F. J.; Donnelly, M. I.; Nebraska Wesleyan Univ.

    1995-09-10

    Malate dehydrogenase and lactate dehydrogenase are members of the structurally and functionally homologous family of 2-ketoacid dehydrogenases. Both enzymes display high specificity for their respective keto substrates, oxaloacetate and pyruvate. Closer analysis of their specificity, however, reveals that the specificity of malate dehydrogenase is much stricter and less malleable than that of lactate dehydrogenase. Site-specific mutagenesis of the two enzymes in an attempt to reverse their specificity has met with contrary results. Conversion of a specific active-site glutamine to arginine in lactate dehydrogenase from Bacillus stearothermophilus generated an enzyme that displayed activity toward oxaloacetate equal to that of the native enzyme toward pyruvate (H. M. Wilks et al. (1988) Science 242, 1541-1544). We have constructed a series of mutants in the mobile, active site loop of the Escherichia coli malate dehydrogenase that incorporate the complementary change, conversion of arginine 81 to glutamine, to evaluate the role of charge distribution and conformational flexibility within this loop in defining the substrate specificity of these enzymes. Mutants incorporating the change R81Q all had reversed specificity, displaying much higher activity toward pyruvate than to the natural substrate, oxaloacetate. In contrast to the mutated lactate dehydrogenase, these reversed-specificity mutants were much less active than the native enzyme. Secondary mutations within the loop of the E. coli enzyme (A80N, A80P, A80P/M85E/D86T) had either no or only moderately beneficial effects on the activity of the mutant enzyme toward pyruvate. The mutation A80P, which can be expected to reduce the overall flexibility of the loop, modestly improved activity toward pyruvate. The possible physiological relevance of the stringent specificity of malate dehydrogenase was investigated. In normal strains of E. coli, fermentative metabolism was not affected by expression of the mutant malate dehydrogenase. However, when expressed in a strain of E. coli unable to ferment glucose, the mutant enzyme restored growth and produced lactic acid as the sole fermentation product.

  9. Utilization of D-Lactate as an Energy Source Supports the Growth of Gluconobacter oxydans.

    PubMed

    Sheng, Binbin; Xu, Jing; Zhang, Yingxin; Jiang, Tianyi; Deng, Sisi; Kong, Jian; Gao, Chao; Ma, Cuiqing; Xu, Ping

    2015-06-15

    d-Lactate was identified as one of the few available organic acids that supported the growth of Gluconobacter oxydans 621H in this study. Interestingly, the strain used d-lactate as an energy source but not as a carbon source, unlike other lactate-utilizing bacteria. The enzymatic basis for the growth of G. oxydans 621H on d-lactate was therefore investigated. Although two putative NAD-independent d-lactate dehydrogenases, GOX1253 and GOX2071, were capable of oxidizing d-lactate, GOX1253 was the only enzyme able to support the d-lactate-driven growth of the strain. GOX1253 was characterized as a membrane-bound dehydrogenase with high activity toward d-lactate, while GOX2071 was characterized as a soluble oxidase with broad substrate specificity toward d-2-hydroxy acids. The latter used molecular oxygen as a direct electron acceptor, a feature that has not been reported previously in d-lactate-oxidizing enzymes. This study not only clarifies the mechanism for the growth of G. oxydans on d-lactate, but also provides new insights for applications of the important industrial microbe and the novel d-lactate oxidase. PMID:25862219

  10. Utilization of d-Lactate as an Energy Source Supports the Growth of Gluconobacter oxydans

    PubMed Central

    Sheng, Binbin; Xu, Jing; Zhang, Yingxin; Jiang, Tianyi; Deng, Sisi; Kong, Jian; Ma, Cuiqing; Xu, Ping

    2015-01-01

    d-Lactate was identified as one of the few available organic acids that supported the growth of Gluconobacter oxydans 621H in this study. Interestingly, the strain used d-lactate as an energy source but not as a carbon source, unlike other lactate-utilizing bacteria. The enzymatic basis for the growth of G. oxydans 621H on d-lactate was therefore investigated. Although two putative NAD-independent d-lactate dehydrogenases, GOX1253 and GOX2071, were capable of oxidizing d-lactate, GOX1253 was the only enzyme able to support the d-lactate-driven growth of the strain. GOX1253 was characterized as a membrane-bound dehydrogenase with high activity toward d-lactate, while GOX2071 was characterized as a soluble oxidase with broad substrate specificity toward d-2-hydroxy acids. The latter used molecular oxygen as a direct electron acceptor, a feature that has not been reported previously in d-lactate-oxidizing enzymes. This study not only clarifies the mechanism for the growth of G. oxydans on d-lactate, but also provides new insights for applications of the important industrial microbe and the novel d-lactate oxidase. PMID:25862219

  11. Creatine Synthesis: An Undergraduate Organic Chemistry Laboratory Experiment

    ERIC Educational Resources Information Center

    Smith, Andri L.; Tan, Paula

    2006-01-01

    Students in introductory chemistry classes typically appreciate seeing the connection between course content and the "real world". For this reason, we have developed a synthesis of creatine monohydrate--a popular supplement used in sports requiring short bursts of energy--for introductory organic chemistry laboratory courses. Creatine monohydrate…

  12. Creatine Synthesis: An Undergraduate Organic Chemistry Laboratory Experiment

    ERIC Educational Resources Information Center

    Smith, Andri L.; Tan, Paula

    2006-01-01

    Students in introductory chemistry classes typically appreciate seeing the connection between course content and the "real world". For this reason, we have developed a synthesis of creatine monohydrate--a popular supplement used in sports requiring short bursts of energy--for introductory organic chemistry laboratory courses. Creatine monohydrate

  13. Creatine Supplementation and Swim Performance: A Brief Review

    PubMed Central

    Hopwood, Melissa J.; Graham, Kenneth; Rooney, Kieron B.

    2006-01-01

    Nutritional supplements are popular among athletes participating in a wide variety of sports. Creatine is one of the most commonly used dietary supplements, as it has been shown to be beneficial in improving performance during repeated bouts of high-intensity anaerobic activity. This review examines the specific effects of creatine supplementation on swimming performance, and considers the effects of creatine supplementation on various measures of power development in this population. Research performed on the effect of creatine supplementation on swimming performance indicates that whilst creatine supplementation is ineffective in improving performance during a single sprint swim, dietary creatine supplementation may benefit repeated interval swim set performance. Considering the relationship between sprint swimming performance and measurements of power, the effect of creatine supplementation on power development in swimmers has also been examined. When measured on a swim bench ergometer, power development does show some improvement following a creatine supplementation regime. How this improvement in power output transfers to performance in the pool is uncertain. Although some evidence exists to suggest a gender effect on the performance improvements seen in swimmers following creatine supplementation, the majority of research indicates that male and female swimmers respond equally to supplementation. A major limitation to previous research is the lack of consideration given to the possible stroke dependant effect of creatine supplementation on swimming performance. The majority of the research conducted to date has involved examination of the freestyle swimming stroke only. The potential for performance improvements in the breaststroke and butterfly swimming strokes is discussed, with regards to the biomechanical differences and differences in efficiency between these strokes and freestyle. Key Points Creatine supplementation does not improve single sprint swimming performance. Creatine supplementation does improve repeated interval swim set performance. Creatine supplementation does improve power development in swimmers when measured on a swim bench ergometer. As a result of the high energy demands of the butterfly and breaststroke competitive swimming styles, potentially, the benefits associated with creatine supplementation and swimming performance could be greater when swimming butterfly or breaststroke, compared to the commonly examined freestyle swimming stroke. PMID:24198677

  14. Highly efficient L-lactate production using engineered Escherichia coli with dissimilar temperature optima for L-lactate formation and cell growth

    PubMed Central

    2014-01-01

    L-Lactic acid, one of the most important chiral molecules and organic acids, is produced via pyruvate from carbohydrates in diverse microorganisms catalyzed by an NAD+-dependent L-lactate dehydrogenase. Naturally, Escherichia coli does not produce L-lactate in noticeable amounts, but can catabolize it via a dehydrogenation reaction mediated by an FMN-dependent L-lactate dehydrogenase. In aims to make the E. coli strain to produce L-lactate, three L-lactate dehydrogenase genes from different bacteria were cloned and expressed. The L-lactate producing strains, 090B1 (B0013-070, ΔldhA::diflldD::Pldh-ldhLca), 090B2 (B0013-070, ΔldhA::diflldD::Pldh-ldhStrb) and 090B3 (B0013-070, ΔldhA::diflldD::Pldh-ldhBcoa) were developed from a previously developed D-lactate over-producing strain, E. coli strain B0013-070 (ack-ptappspflBdldpoxBadhEfrdA) by: (1) deleting ldhA to block D-lactate formation, (2) deleting lldD to block the conversion of L-lactate to pyruvate, and (3) expressing an L-lactate dehydrogenase (L-LDH) to convert pyruvate to L-lactate under the control of the ldhA promoter. Fermentation tests were carried out in a shaking flask and in a 25-l bioreactor. Strains 090B1, 090B2 or 090B3 were shown to metabolize glucose to L-lactate instead of D-lactate. However, L-lactate yield and cell growth rates were significantly different among the metabolically engineered strains which can be attributed to a variation between temperature optimum for cell growth and temperature optimum for enzymatic activity of individual L-LDH. In a temperature-shifting fermentation process (cells grown at 37°C and L-lactate formed at 42°C), E. coli 090B3 was able to produce 142.2 g/l of L-lactate with no more than 1.2 g/l of by-products (mainly acetate, pyruvate and succinate) accumulated. In conclusion, the production of lactate by E. coli is limited by the competition relationship between cell growth and lactate synthesis. Enzymatic properties, especially the thermodynamics of an L-LDH can be effectively used as a factor to regulate a metabolic pathway and its metabolic flux for efficient L-lactate production. Highlights The enzymatic thermodynamics was used as a tool for metabolic regulation. ► minimizing the activity of L-lactate dehydrogenase in growth phase improved biomass accumulation. ► maximizing the activity of L-lactate dehydrogenase improved lactate productivity in production phase. PMID:24884499

  15. Energetic status and mitochondrial oxidative capacity of rat skeletal muscle in response to creatine analogue ingestion.

    PubMed

    Freyssenet, D; Berthon, P; Barthélémy, J C; Busso, T; Geyssant, A; Denis, C

    1995-03-14

    A creatine analogue, beta-guanidinopropionic acid (beta-GPA), was administered in the food (1% w/w) of 8 male rats for 6 weeks, while 8 control rats received a standard diet. Mitochondrial oxidative capacity and cytosolic modulators of mitochondrial oxidative phosphorylation (free ADP, ATP-to-free ADP ratio) were evaluated in the soleus and extensor digitorum longus (EDL) muscles. Mitochondrial adaptation to the diet was significantly different between muscles. Citrate synthase activity and mitochondrial ATP synthesis rate were 35 and 45% higher in EDL muscle, respectively, whereas they were virtually unchanged in the soleus muscle. In both muscles, 3-hydroxyacyl-CoA dehydrogenase activity remained unaffected. Regardless of muscle type, creatine, phosphocreatine and ATP concentrations, as well as the total adenine nucleotide content (ATP + ADP + AMP), were significantly lower in beta-GPA fed rats. Whereas free ADP concentration remained unchanged, a significantly greater decrease in ATP-to-free ADP ratio was observed in EDL than in the soleus muscle. It is suggested that regulation of mitochondrial oxidative phosphorylation, through changes in metabolite concentrations, could be an important factor to consider for mitochondrial adaptation induced by beta-GPA feeding. PMID:7893727

  16. Sugar-glycerol cofermentations in lactobacilli: the fate of lactate.

    PubMed Central

    Veiga da Cunha, M; Foster, M A

    1992-01-01

    The simultaneous fermentation of glycerol and sugar by lactobacillus brevis B22 and Lactobacillus buchneri B190 increases both the growth rate and total growth. The reduction of glycerol to 1,3-propanediol by the lactobacilli was found to influence the metabolism of the sugar cofermented by channelling some of the intermediate metabolites (e.g., pyruvate) towards NADH-producing (rather than NADH-consuming) reactions. Ultimately, the absolute requirement for NADH to prevent the accumulation of 3-hydroxypropionaldehyde leads to a novel lactate-glycerol cofermentation. As a result, additional ATP can be made not only by (i) converting pyruvate to acetate via acetyl phosphate rather than to the ethanol usually found and (ii) oxidizing part of the intermediate pyruvate to acetate instead of the usual reduction to lactate but also by (iii) reoxidation of accumulated lactate to acetate via pyruvate. The conversion of lactate to pyruvate is probably catalyzed by NAD-independent lactate dehydrogenases that are found only in the cultures oxidizing lactate and producing 1,3-propanediol, suggesting a correlation between the expression of these enzymes and a raised intracellular NAD/NADH ratio. The enzymes metabolizing glycerol (glycerol dehydratase and 1,3-propanediol dehydrogenase) were expressed in concert without necessary induction by added glycerol, although their expression may also be influenced by the intracellular NAD/NADH ratio set by the different carbohydrates fermented. PMID:1732191

  17. Single Prolonged Stress Decreases Glutamate, Glutamine, and Creatine Concentrations In The Rat Medial Prefrontal Cortex

    PubMed Central

    Knox, Dayan; Perrine, Shane A.; George, Sophie A.; Galloway, Matthew P.; Liberzon, Israel

    2010-01-01

    Application of Single Prolonged Stress (SPS) in rats induces changes in neuroendocrine function and arousal that are characteristic of Post Traumatic Stress Disorder (PTSD). PTSD, in humans, is associated with decreased neural activity in the prefrontal cortex, increased neural activity in the amygdala complex, and reduced neuronal integrity in the hippocampus. However, the extent to which SPS models these aspects of PTSD has not been established. In order to address this, we used high-resolution magic angle spinning proton magnetic resonance spectroscopy (HR-MAS 1H MRS) ex vivo to assay levels of neurochemicals critical for energy metabolism (creatine and lactate), excitatory (glutamate and glutamine) and inhibitory (gamma amino butyric acid (GABA)) neurotransmission, and neuronal integrity (N-acetyl aspartate (NAA)) in the medial prefrontal cortex (mPFC), amygdala complex, and hippocampus of SPS and control rats. Glutamate, glutamine, and creatine levels were decreased in the mPFC of SPS rats when compared to controls, which suggests decreased excitatory tone in this region. SPS did not alter the neurochemical profiles of either the hippocampus or amygdala. These data suggest that SPS selectively attenuates excitatory tone, without a disruption of neuronal integrity, in the mPFC. PMID:20546834

  18. Oral creatine supplementation on performance of Quarter Horses used in barrel racing.

    PubMed

    Teixeira, F A; Araújo, A L; Ramalho, L O; Adamkosky, M S; Lacerda, T F; Coelho, C S

    2016-06-01

    The aim of this study was to evaluate the effects of oral creatine supplementation on the athletic performance of equines used for barrel racing. Ten healthy Quarter Horses, or Quarter Horse crossbred, weighing 429.7 ± 25.3 kg and with mean age of 3.8 ± 1.2 years, were used. Animals were evaluated in four different moments (M1, M2, M3, M4), and between M3 and M4, they were supplemented with 28 g of creatine/100 kg of body weight, orally, for 45 days. Although significant alterations for LDH activity, plasma glucose and packed cell volume were observed, it was possible to conclude that there was no improvement in the athletic performance for the animals used on the experiment, as there were no changes in time scores, heart rate and plasma lactate, variables considered as performance indicators, before and after supplementation. PMID:26613801

  19. Creatine and the Liver: Metabolism and Possible Interactions.

    PubMed

    Barcelos, R P; Stefanello, S T; Mauriz, J L; Gonzalez-Gallego, J; Soares, F A A

    2016-01-01

    The process of creatine synthesis occurs in two steps, catalyzed by L-arginine:glycine amidinotransferase (AGAT) and guanidinoacetate N-methyltransferase (GAMT), which take place mainly in kidney and liver, respectively. This molecule plays an important energy/pH buffer function in tissues, and to guarantee the maintenance of its total body pool, the lost creatine must be replaced from diet or de novo synthesis. Creatine administration is known to decrease the consumption of Sadenosyl methionine and also reduce the homocysteine production in liver, diminishing fat accumulation and resulting in beneficial effects in fatty liver and non-alcoholic liver disease. Different studies have shown that creatine supplementation could supply brain energy, presenting neuroprotective effects against the encephalopathy induced by hyperammonemia in acute liver failure. Creatine is also taken by many athletes for its ergogenic properties. However, little is known about the adverse effects of creatine supplementation, which are barely described in the literature, with reports of mainly hypothetical effects arising from a small number of scientific publications. Antioxidant effects have been found in several studies, although one of the theories regarding the potential for toxicity from creatine supplementation is that it can increase oxidative stress and potentially form carcinogenic compounds. PMID:26202197

  20. Structure and Function of Plasmodium falciparum malate dehydrogenase: Role of Critical Amino Acids in C-substrate Binding Procket

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Malaria parasite thrives on anaerobic fermentation of glucose for energy. Earlier studies from our lab have demonstrated that a cytosolic malate dehydrogenase (PfMDH) with striking similarity to lactate dehydrogenase (PfLDH) might complement PfLDH function in Plasmodium falciparum. The N-terminal g...

  1. Analysis of Quaternary Structure of a [LDH-like] Malate Dehydrogenase of Plasmodium falciparum with Oligomeric Mutants

    Technology Transfer Automated Retrieval System (TEKTRAN)

    L-Malate dehydrogenase (PfMDH) from Plasmodium falciparum, the causative agent for the most severe form of malaria, has shown remarkable similarities to L-lactate dehydrogenase (PfLDH). PfMDH is more closely related to [LDH-like] MDHs characterized in archea and other prokaryotes. Initial sequence a...

  2. Thermostable amperometric lactate biosensor with Clostridium thermocellum L-LDH for the measurement of blood lactate.

    PubMed

    Ozkan, Melek; Erhan, Elif; Terzi, Ozlem; Tan, Ibrahim; Ozöner, Seyda Korkut

    2009-10-15

    The gene for Clostridium thermocellum L-lactate dehydrogenase enzyme was cloned into pGEX-4T-2 purification vector to supply a source for a thermostable enzyme in order to produce a stable lactate biosensor working at relatively high temperatures. The purified thermostable enzyme (t-LDH) was then immobilized on a gold electrode via polymerization of polygluteraldehyde and pyrrol resulting in a conductive co-polymer. t-LDH working electrode (t-LDHE) was used for determination of lactate in CHES buffer. Amperometric response of the produced electrodes was measured as a function of lactate concentration, at a fixed bias voltage of 200 mV in a three-electrode system. The linear range and sensitivity of the biosensor was investigated at various temperatures in the range of 25-60 degrees C. The sensitivity t-LDHE increased with increasing the temperature and reached its highest value at 60 degrees C. The calculated value was nearly 70 times higher as compared to the sensitivity value of the same electrode tested at 25 degrees C. The sensing parameters of t-LDHE were compared with the electrodes produced by commercially available rabbit muscle LDH (m-LDH). The sensitivity of t-LDHE was nearly 8 times higher than that of m-LDHE. t-LDHE was found to retain its activity for a week incubation at refrigerator (+5 degrees C), while m-LDHE lost its activity in this period. t-LDHE was also tested in the presence of human blood serum. The results showed that the current increased with increasing concentrations of lactate in the human blood serum and the biosensor is more sensitive to serum lactate as well as the commercial lactate dissolved in serum as compared to the commercial lactate dissolved in CHES buffer. PMID:19635378

  3. Combination of International Scoring System 3, High Lactate Dehydrogenase, and t(4;14) and/or del(17p) Identifies Patients With Multiple Myeloma (MM) Treated With Front-Line Autologous Stem-Cell Transplantation at High Risk of Early MM Progression–Related Death

    PubMed Central

    Moreau, Philippe; Cavo, Michele; Sonneveld, Pieter; Rosinol, Laura; Attal, Michel; Pezzi, Annalisa; Goldschmidt, Hartmut; Lahuerta, Juan Jose; Marit, Gerald; Palumbo, Antonio; van der Holt, Bronno; Bladé, Joan; Petrucci, Maria Teresa; Neben, Kai; san Miguel, Jesus; Patriarca, Francesca; Lokhorst, Henk; Zamagni, Elena; Hulin, Cyrille; Gutierrez, Norma; Facon, Thierry; Caillot, Denis; Benboubker, Lotfi; Harousseau, Jean-Luc; Leleu, Xavier; Avet-Loiseau, Hervé; Mary, Jean-Yves

    2014-01-01

    Purpose To construct and validate among patients with multiple myeloma (MM) who were treated with intensive therapy a prognostic index of early MM progression–related death. Patients and Methods Patient-level data from the Intergroupe Francophone du Myélome (IFM) 2005-01 trial (N = 482) were used to construct the prognostic index. The event was MM progression–related death within 2 years from treatment initiation. The index was validated using data from three other trials: the Gruppo Italiano Malattie Ematologiche dell' Adulto (GIMEMA) 26866138-MMY-3006 trial (N = 480), the Programa para el Estudio de la Terapéutica en Hemopatía Maligna (PETHEMA)–GEMMENOS65 trial (N = 390), and the Hemato-Oncologie voor Volwassenen Nederland (HOVON) –65/German-Speaking Myeloma Multicenter Group (GMMG) –HD4 trial (N = 827). Results The risk of early MM progression–related death was related to three independent prognostic variables: lactate dehydrogenase (LDH) higher than than normal, International Staging System 3 (ISS3), and adverse cytogenetics [t(4;14) and/or del(17p)]. These three variables enabled the definition of an ordinal prognostic classification composed of four scores (0 to 3). Patients with a score of 3, defined by the presence of t(4;14) and/or del(17p) in addition to ISS3 and/or high LDH, comprised 5% (20 of 387 patients) to 8% (94 of 1,139 patients) of the patients in the learning and validation samples, respectively, and they had a very poor prognosis. When applied to the population of 855 patients who had received bortezomib-based induction therapy in the four trials, the prognostic classification was also able to segregate patients into four categories, with a very poor prognosis attributed to patients with a score of 3. Conclusion Our model allows the simple definition of a subgroup of MM patients at high risk of early MM progression–related death despite the use of the most modern and effective strategies. PMID:24888806

  4. RNA silencing of lactate dehydrogenase gene in Rhizopus oryzae

    PubMed Central

    Gheinani, Ali Hashemi; Jahromi, Neda Haghayegh; Feuk-Lagerstedt, Elisabeth; Taherzadeh, Mohammad J

    2011-01-01

    Rhizopus oryzae is a filamentous fungus, belonging to the order Mucorales. It can ferment a wide range of carbohydrates hydrolyzed from lignocellulosic materials and even cellobiose to produce ethanol. However, R. oryzae also produces lactic acid as a major metabolite, which reduces the yield of ethanol. In this study, we show that significant reduction of lactic acid production could be achieved by short (25nt) synthetic siRNAs targeting the ldhA gene. The average yield of lactic acid production by R. oryzae during the batch fermentation process, where glucose had been used as a sole carbon source, diminished from 0.07gm/gm in wild type to 0.01gm/gm in silenced samples. In contrast, the average yield of ethanol production increased from 0.39gm/gm in wild type to 0.45gm/gm in silenced samples. These results show 85.7% (gm/gm) reduction in lactic acid production as compared with the wild type R. oryzae, while an increase of 15.4% (gm/gm) in ethanol yield. PMID:21769297

  5. Multichannel Simultaneous Determination of Activities of Lactate Dehydrogenase

    SciTech Connect

    Ma, L.

    2000-09-12

    It is very important to find the best conditions for some enzymes to do the best catalysis in current pharmaceutical industries. Based on the results above, we could say that this set-up could be widely used in finding the optimal condition for best enzyme activity of a certain enzyme. Instead of looking for the best condition for enzyme activity by doing many similar reactions repeatedly, we can complete this assignment with just one run if we could apply enough conditions.

  6. The Partial Purification and Characterization of Lactate Dehydrogenase.

    ERIC Educational Resources Information Center

    Wolf, Edward C.

    1988-01-01

    Offers several advantages over other possibilities as the enzyme of choice for a student's first exposure to a purification scheme. Uses equipment and materials normally found in biochemistry laboratories. Incorporates several important biochemical techniques including spectrophotometry, chromatography, centrifugation, and electrophoresis. (MVL)

  7. Lactate Dehydrogenase Catalysis: Roles of Keto, Hydrated, and Enol Pyruvate

    ERIC Educational Resources Information Center

    Meany, J. E.

    2007-01-01

    Many carbonyl substrates of oxidoreductase enzymes undergo hydration and enolization so that these substrate systems are partitioned between keto, hydrated (gem-diol), and enol forms in aqueous solution. Some oxidoreductase enzymes are subject to inhibition by high concentrations of substrate. For such enzymes, two questions arise pertaining to…

  8. Lactate Dehydrogenase Catalysis: Roles of Keto, Hydrated, and Enol Pyruvate

    ERIC Educational Resources Information Center

    Meany, J. E.

    2007-01-01

    Many carbonyl substrates of oxidoreductase enzymes undergo hydration and enolization so that these substrate systems are partitioned between keto, hydrated (gem-diol), and enol forms in aqueous solution. Some oxidoreductase enzymes are subject to inhibition by high concentrations of substrate. For such enzymes, two questions arise pertaining to

  9. [Autoimmune hemolytic anemia with normal serum lactate dehydrogenase level].

    PubMed

    Mizuno, Hideaki; Hangaishi, Akira; Saika, Makoto; Morioka, Takehiko; Ando, Yayoi; Kida, Michiko; Usuki, Kensuke

    2015-11-01

    We herein report two cases of AIHA (autoimmune hemolytic anemia), a 25-year-old woman and a 77-year-old man, who presented with normal serum LDH values. Though in these two cases, low hemoglobin and haptoglobin, high total bilirubin and positive direct Coombs' test results led to the diagnosis of AIHA, both patients had normal LDH levels (218 and 187 IU/l). Both cases were successfully treated with prednisone. In the diagnosis of AIHA, elevated LDH is usually used as a marker of hemolysis. However, medical records of 24 AIHA patients collected in our institute from January 2001 to August 2012 revealed LDH levels to have been normal in 25% of these cases. This report indicates the importance of obtaining complete information about the blood testing of patients and taking these data into account when considering the diagnosis of AIHA. PMID:26666722

  10. Lactation and reproduction*

    PubMed Central

    Thomson, A. M.; Hytten, F. E.; Black, A. E.

    1975-01-01

    The authors review the literature on the effect of lactation on fertility in the absence of contraception and on the effects of contraceptive measures on lactation. They examine data from several countries on the intervals between births and on the return of menstruation and ovulation after childbirth, comparing lactating with nonlactating women. They conclude that lactation is an inefficient contraceptive for the individual, but that in populations sustained lactation is associated with reduced fertility. Possible physiological mechanisms causing lactation amenorrhoea are discussed. Though much of the literature on the effect of contraceptives on lactation is inadequate, there is general agreement that the estrogen component of hormonal preparations has an adverse effect on lactation, but that progestins alone do not. Many questions remain. Is this effect seen in established lactation, or only in the puerperal period? Is it a direct pharmacological effect, or are pill-users the mothers least motivated to maintain breast-feeding? Does a close relationship exist between hormones given and lactation performance? The authors comment on some of the technical deficiencies of previous studies in this field and discuss practical possibilities of, and limitations to, obtaining adequate scientific information in the future. PMID:1084804

  11. Effect of physical exercise on changes in activities of creatine kinase, cytochrome c oxidase and ATP levels caused by ovariectomy.

    PubMed

    Siebert, Cassiana; Kolling, Janaína; Scherer, Emilene B S; Schmitz, Felipe; da Cunha, Maira Jaqueline; Mackedanz, Vanize; de Andrade, Rodrigo B; Wannmacher, Clovis M D; Wyse, Angela T S

    2014-09-01

    The reduction in the secretion of ovarian hormones, principally estrogen, is a consequence of menopause. Estrogens act primarily as female sex hormones, but also exert effects on different physiological systems including the central nervous system. The treatment normally used to reduce the symptoms of menopause is the hormone therapy, which seems to be effective in treating symptoms, but it may be responsible for adverse effects. Based on this, there is an increasing demand for alternative therapies that minimize signs and symptoms of menopause. In the present study we investigated the effect of ovariectomy and/or physical exercise on the activities of energy metabolism enzymes, such as creatine kinase (cytosolic and mitochondrial fractions), pyruvate kinase, succinate dehydrogenase, complex II, cytochrome c oxidase, as well as on ATP levels in the hippocampus of adult rats. Adult female Wistar rats with 90 days of age were subjected to ovariectomy (an animal model widely used to mimic the postmenopausal changes). Thirty days after the procedure, the rats were submitted to the exercise protocol, which was performed three times a week for 30 days. Twelve hours after the last training session, the rats were decapitated for subsequent biochemical analyzes. Results showed that ovariectomy did not affect the activities of pyruvate kinase, succinate dehydrogenase and complex II, but decreased the activities of creatine kinase (cytosolic and mitochondrial fractions) and cytochrome c oxidase. ATP levels were also reduced. Exercise did not produce the expected results since it was only able to partially reverse the activity of creatine kinase cytosolic fraction. The results of this study suggest that estrogen deficiency, which occurs as a result of ovariectomy, affects generation systems and energy homeostasis, reducing ATP levels in hippocampus of adult female rats. PMID:24810635

  12. The Use of Varying Creatine Regimens on Sprint Cycling

    PubMed Central

    Havenetidis, Konstantinos; Matsouka, Ourania; Cooke, Carlton Brian; Theodorou, Apostolos

    2003-01-01

    This study aimed to determine the effects of different acute creatine loadings (ACRL) on repeated cycle sprints. Twenty-eight active subjects divided into the control (n=7) and the experimental (n=21) group. The exercise protocol comprised three 30s Anaerobic Wingate Tests (AWT) interspersed with six minutes recovery, without any supplements ingested and following placebo and creatine ingestion, according to each ACRL (40g, 100g and 135g throughout a four-day period). Blood and urinary creatine levels were also determined from the experimental group for each ACRL. Protein intake (across all groups) was held constant during the study. There were no changes in protein intake or performance of the control group. For the experimental group creatine supplementation produced significant (p<0.01) increases in body mass (82.5 ± 1.4kg pre vs 82.9 ± 1.2kg post), blood (0.21 ± 0.04mmol·l-1 pre vs 2.24 ± 0.98mmol·l-1 post), and urinary creatine (0.23 ± 0.09mmol·l-1 pre vs 4.29 ± 1.98mmol·l-1 post). No significant differences were found between the non-supplement and placebo condition. Creatine supplementation produced an average improvement of 0.7%, 11.8% and 11.1% for the 40g, 100g and 135g ACRL respectively. However, statistics revealed significant (p<0.01) differences only for the 100g and 135g ACRL. Mean ± SD values for the 100g ACRL for mean and minimum power were 612 ± 180W placebo vs 693 ± 221W creatine and 381 ± 35W placebo vs 415 ± 11W creatine accordingly. For the 135g ACRL the respective performance values were 722 ± 215W placebo vs 810 ± 240W creatine and 405 ± 59W placebo vs 436 ± 30W creatine. These data indicate that a 100g compared to 40g ACRL produces a greater potentiation of performance whilst, greater quantities of creatine ingestion (135g ACRL) can not provide a greater benefit. PMID:24627660

  13. Plant Formate Dehydrogenase

    SciTech Connect

    John Markwell

    2005-01-10

    The research in this study identified formate dehydrogenase, an enzyme that plays a metabolic role on the periphery of one-carbon metabolism, has an unusual localization in Arabidopsis thaliana and that the enzyme has an unusual kinetic plasticity. These properties make it possible that this enzyme could be engineered to attempt to engineer plants with an improved photosynthetic efficiency. We have produced transgenic Arabidopsis and tobacco plants with increased expression of the formate dehydrogenase enzyme to initiate further studies.

  14. Hematological and biochemical findings in pregnant, postfoaling, and lactating jennies.

    PubMed

    Bonelli, F; Rota, A; Corazza, M; Serio, D; Sgorbini, M

    2016-04-15

    The aims of this study were to (1) verify if significant changes occur in hematological and biochemical parameters in jennies during the last 2 months of pregnancy and the first 2 months of lactation, and (2) determine any differences with mares. Hematological and biochemical parameters were evaluated in jennies every 15 days during late pregnancy, parturition, and early lactation. The Kolmogorov-Smirnov test, analysis of variance for repeated measurements and Tukey's multiple comparison test as post hoc were applied. The significance level was set at P < 0.05. Statistical analysis showed differences related to time for Red Blood Cells (RBC) count and Hematocrit (HCT), White Blood Cells (WBC) count, platelet count (PLT), total proteins, blood urea, triglycerides and total cholesterol concentrations, aspartate aminotransferase, gamma-glutamyltransferase, creatine-phosphokinase activities, sodium (Na) and potassium (K). RBC and HCT were higher in late pregnancy than at foaling and during lactation. The relative anemia might be due to increased water ingestion because of fluid losses. The WBC count was higher at foaling than during late pregnancy and lactation. This could be related to the release of cortisol and catecholamine during delivery. The PLT trend showed lower values from delivery to the first 2 months of lactation compared to late gestation. Blood urea increased near parturition, and then remained constant during delivery and lactation, which might be due to the high energy demand at the beginning of lactation. Triglycerides and total cholesterol showed a decrease from delivery through the lactation period. Thus, jennies seem to have a similar metabolism of fats to ponies and draft horse mares, characterized by a greater fat content and mobilization than light breed horses. Aspartate aminotransferase activity decreased at parturition and early lactation, probably because of a predominance of anabolic over catabolic processes during pregnancy. Gamma-glutamyltransferase activity was lower at delivery and during lactation than at late gestation. This could be due to a physiological load on the liver in the perinatal period. Gamma-glutamyltransferase activity was always higher than in mares, but within the normal range for adult donkeys. Creatine-phosphokinase decreased near delivery, then was constant from parturition through the first 2 months of lactation. Na decreased during lactation, probably due to an increased renal retention mediated by aldosterone release during pregnancy. K showed the same trend as Na, and concentrations are in line with the species. The higher K during pregnancy may be due to reabsorption by the gut. Total proteins decreased more during the postpartum period and lactation than in the gestational period. In conclusion, our results showed significant changes in hematological and biochemical parameters in jennies during the last 2 months of pregnancy and the first 2 months of lactation and these changes are only partially comparable to mares. PMID:26792379

  15. Metabolic control analysis of L-lactate synthesis pathway in Rhizopus oryzae As 3.2686.

    PubMed

    Ke, Wei; Chang, Shu; Chen, Xiaoju; Luo, Shuizhong; Jiang, Shaotong; Yang, Peizhou; Wu, Xuefeng; Zheng, Zhi

    2015-11-01

    The relationship between the metabolic flux and the activities of the pyruvate branching enzymes of Rhizopus oryzae As 3.2686 during L-lactate fermentation was investigated using the perturbation method of aeration. The control coefficients for five enzymes, pyruvate dehydrogenase (PDH), pyruvate carboxylase (PC), pyruvate decarboxylase (PDC), lactate dehydrogenase (LDH), and alcohol dehydrogenase (ADH), were calculated. Our results indicated significant correlations between PDH and PC, PDC and LDH, PDC and ADH, LDH and ADH, and PDC and PC. It also appeared that PDH, PC, and LDH strongly controlled the L-lactate flux; PDH and ADH strongly controlled the ethanol flux; while PDH and PC strongly controlled the acetyl coenzyme A flux and the oxaloacetate flux. Further, the flux control coefficient curves indicated that the control of the system gradually transferred from PDC to PC during the steady state. Therefore, PC was the key rate-limiting enzyme that controls the flux distribution. PMID:26288952

  16. Water recycling in lactation.

    PubMed

    Baverstock, P; Green, B

    1975-02-21

    During lactation, female rodents, dingoes, and kangaroos consume urine and feces excreted by the young. Studies with tritiated water as a tracer for native water showed that roughly one-third of the water secreted as milk was returned to the mother. The results are cogent to studies of water balance of lactation and to current methods used for estimating milk production. PMID:1167701

  17. Physiology of lactation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The breast changes in size, shape, and function during puberty, pregnancy, and lactation. The physiology of lactation is reviewed here. The breast is composed of fat and connective tissue that supports a tubuloalveolar structure. During development, anatomic changes involving new lobule formation an...

  18. Lactate Racemization as a Rescue Pathway for Supplying d-Lactate to the Cell Wall Biosynthesis Machinery in Lactobacillus plantarum

    PubMed Central

    Goffin, Philippe; Deghorain, Marie; Mainardi, Jean-Luc; Tytgat, Isabelle; Champomier-Vergès, Marie-Christine; Kleerebezem, Michiel; Hols, Pascal

    2005-01-01

    Lactobacillus plantarum is a lactic acid bacterium that produces d- and l-lactate using stereospecific NAD-dependent lactate dehydrogenases (LdhD and LdhL, respectively). However, reduction of glycolytic pyruvate by LdhD is not the only pathway for d-lactate production since a mutant defective in this activity still produces both lactate isomers (T. Ferain, J. N. Hobbs, Jr., J. Richardson, N. Bernard, D. Garmyn, P. Hols, N. E. Allen, and J. Delcour, J. Bacteriol. 178:5431-5437, 1996). Production of d-lactate in this species has been shown to be connected to cell wall biosynthesis through its incorporation as the last residue of the muramoyl-pentadepsipeptide peptidoglycan precursor. This particular feature leads to natural resistance to high concentrations of vancomycin. In the present study, we show that L. plantarum possesses two pathways for d-lactate production: the LdhD enzyme and a lactate racemase, whose expression requires l-lactate. We report the cloning of a six-gene operon, which is involved in lactate racemization activity and is positively regulated by l-lactate. Deletion of this operon in an L. plantarum strain that is devoid of LdhD activity leads to the exclusive production of l-lactate. As a consequence, peptidoglycan biosynthesis is affected, and growth of this mutant is d-lactate dependent. We also show that the growth defect can be partially restored by expression of the d-alanyl-d-alanine-forming Ddl ligase from Lactococcus lactis, or by supplementation with various d-2-hydroxy acids but not d-2-amino acids, leading to variable vancomycin resistance levels. This suggests that L. plantarum is unable to efficiently synthesize peptidoglycan precursors ending in d-alanine and that the cell wall biosynthesis machinery in this species is specifically dedicated to the production of peptidoglycan precursors ending in d-lactate. In this context, the lactate racemase could thus provide the bacterium with a rescue pathway for d-lactate production upon inactivation or inhibition of the LdhD enzyme. PMID:16166538

  19. Adverse effects of creatine supplementation: fact or fiction?

    PubMed

    Poortmans, J R; Francaux, M

    2000-09-01

    The consumption of oral creatine monohydrate has become increasingly common among professional and amateur athletes. Despite numerous publications on the ergogenic effects of this naturally occurring substance, there is little information on the possible adverse effects of this supplement. The objectives of this review are to identify the scientific facts and contrast them with reports in the news media, which have repeatedly emphasised the health risks of creatine supplementation and do not hesitate to draw broad conclusions from individual case reports. Exogenous creatine supplements are often consumed by athletes in amounts of up to 20 g/day for a few days, followed by 1 to 10 g/day for weeks, months and even years. Usually, consumers do not report any adverse effects, but body mass increases. There are few reports that creatine supplementation has protective effects in heart, muscle and neurological diseases. Gastrointestinal disturbances and muscle cramps have been reported occasionally in healthy individuals, but the effects are anecdotal. Liver and kidney dysfunction have also been suggested on the basis of small changes in markers of organ function and of occasional case reports, but well controlled studies on the adverse effects of exogenous creatine supplementation are almost nonexistent. We have investigated liver changes during medium term (4 weeks) creatine supplementation in young athletes. None showed any evidence of dysfunction on the basis of serum enzymes and urea production. Short term (5 days), medium term (9 weeks) and long term (up to 5 years) oral creatine supplementation has been studied in small cohorts of athletes whose kidney function was monitored by clearance methods and urine protein excretion rate. We did not find any adverse effects on renal function. The present review is not intended to reach conclusions on the effect of creatine supplementation on sport performance, but we believe that there is no evidence for deleterious effects in healthy individuals. Nevertheless, idiosyncratic effects may occur when large amounts of an exogenous substance containing an amino group are consumed, with the consequent increased load on the liver and kidneys. Regular monitoring is compulsory to avoid any abnormal reactions during oral creatine supplementation. PMID:10999421

  20. Pyruvate Dehydrogenase and Pyruvate Dehydrogenase Kinase Expression in Non Small Cell Lung Cancer and Tumor-Associated Stroma1

    PubMed Central

    Koukourakis, Michael I; Giatromanolaki, Alexandra; Sivridis, Efthimios; Gatter, Kevin C; Harris, Adrian L; “Tumor and Angiogenesis Research Group”

    2005-01-01

    Abstract Pyruvate dehydrogenase (PDH) catalyzes the conversion of pyruvate to acetyl-coenzyme A, which enters into the Krebs cycle, providing adenosine triphosphate (ATP) to the cell. PDH activity is under the control of pyruvate dehydrogenase kinases (PDKs). Under hypoxic conditions, conversion of pyruvate to lactate occurs, a reaction catalyzed by lactate dehydrogenase 5 (LDH5). In cancer cells, however, pyruvate is transformed to lactate occurs, regardless of the presence of oxygen (aerobic glycolysis/Warburg effect). Although hypoxic intratumoral conditions account for HIF1α stabilization and induction of anaerobic metabolism, recent data suggest that high pyruvate concentrations also result in HIF1α stabilization independently of hypoxia. In the present immunohistochemical study, we provide evidence that the PDH/PDK pathway is repressed in 73% of non small cell lung carcinomas, which may be a key reason for HIF1α stabilization and “aerobic glycolysis.” However, about half of PDH-deficient carcinomas are not able to switch on the HIF pathway, and patients harboring these tumors have an excellent postoperative outcome. A small subgroup of clinically aggressive tumors maintains a coherent PDH and HIF/LDH5 expression. In contrast to cancer cells, fibroblasts in the tumor-supporting stroma exhibit an intense PDH but reduced PDK1 expression favoring maximum PDH activity. This means that stroma may use lactic acid produced by tumor cells, preventing the creation of an intolerable intratumoral acidic environment at the same time. PMID:15736311

  1. Evidences of Basal Lactate Production in the Main White Adipose Tissue Sites of Rats. Effects of Sex and a Cafeteria Diet

    PubMed Central

    Arriarán, Sofía; Agnelli, Silvia; Sabater, David; Remesar, Xavier; Fernández-López, José Antonio; Alemany, Marià

    2015-01-01

    Female and male adult Wistar rats were fed standard chow or a simplified cafeteria diet for one month. Then, the rats were killed and the white adipose tissue (WAT) in four sites: perigonadal, retroperitoneal, mesenteric and subcutaneous (inguinal) were sampled and frozen. The complete WAT weight in each site was measured. Gene expression analysis of key lipid and glucose metabolism enzymes were analyzed, as well as tissue and plasma lactate and the activity of lactate dehydrogenase. Lactate gradients between WAT and plasma were estimated. The influence of sex and diet (and indirectly WAT mass) on lactate levels and their relationships with lactate dehydrogenase activity and gene expressions were also measured. A main conclusion is the high production of lactate by WAT, practically irrespective of site, diet or sex. Lactate production is a direct correlate of lactate dehydrogenase activity in the tissue. Furthermore, lactate dehydrogenase activity is again directly correlated with the expression of the genes Ldha and Ldhb for this enzyme. In sum, the ability to produce lactate by WAT is not directly dependent of WAT metabolic state. We postulate that, in WAT, a main function of the lactate dehydrogenase path may be that of converting excess available glucose to 3C fragments, as a way to limit tissue self-utilization as substrate, to help control glycaemia and/or providing short chain substrates for use as energy source elsewhere. More information must be gathered before a conclusive role of WAT in the control of glycaemia, and the full existence of a renewed glucose-lactate-fatty acid cycle is definitely established. PMID:25741703

  2. The effects of creatine pyruvate and creatine citrate on performance during high intensity exercise

    PubMed Central

    Jäger, Ralf; Metzger, Jan; Lautmann, Karin; Shushakov, Vladimir; Purpura, Martin; Geiss, Kurt-Reiner; Maassen, Norbert

    2008-01-01

    Background A double-blind, placebo-controlled, randomized study was performed to evaluate the effect of oral creatine pyruvate (Cr-Pyr) and creatine citrate (Cr-Cit) supplementation on exercise performance in healthy young athletes. Methods Performance during intermittent handgrip exercise of maximal intensity was evaluated before (pretest) and after (posttest) 28 days of Cr-Pyr (5 g/d, n = 16), Cr-Cit (5 g/d, n = 16) or placebo (pla, 5 g/d, n = 17) intake. Subjects performed ten 15-sec exercise intervals, each followed by 45 sec rest periods. Results Cr-Pyr (p < 0.001) and Cr-Cit (p < 0.01) significantly increased mean power over all intervals. Cr-Cit increased force during the first and second interval (p < 0.01) compared to placebo. The effect of Cr-Cit on force decreased over time and the improvement was not significant at the sixth and ninth interval, whereas Cr-Pyr significantly increased force during all intervals (p < 0.001). Cr-Pyr (p < 0.001) and Cr-Cit (p < 0.01) resulted in an increase in contraction velocity, whereas only Cr-Pyr intake significantly (p < 0.01) increased relaxation velocity. Oxygen consumption measured during rest periods significantly increased with Cr-Pyr (p < 0.05), whereas Cr-Cit and placebo intake did not result in significant improvements. Conclusion It is concluded that four weeks of Cr-Pyr and Cr-Cit intake significantly improves performance during intermittent handgrip exercise of maximal intensity and that Cr-Pyr might benefit endurance, due to enhanced activity of the aerobic metabolism. PMID:18269769

  3. Creatine administration prevents Na+,K+-ATPase inhibition induced by intracerebroventricular administration of isovaleric acid in cerebral cortex of young rats.

    PubMed

    Ribeiro, César Augusto João; Leipnitz, Guilhian; Amaral, Alexandre Umpierrez; de Bortoli, Giorgia; Seminotti, Bianca; Wajner, Moacir

    2009-03-25

    Isovaleric acidemia (IVAcidemia) is an inborn error of metabolism due to deficiency of isovaleryl-CoA dehydrogenase activity, leading to predominant accumulation of isovaleric acid (IVA). Patients affected by IVAcidemia suffer from acute episodes of encephalopathy, whose underlying mechanisms are poorly known. In the present study we investigated whether an intracerebroventricular injection of IVA could compromise energy metabolism in cerebral cortex of young rats. IVA administration significantly inhibited (14)CO(2) production from acetate (22%) and citrate synthase activity (20%) in cerebral cortex homogenates prepared 24 h after injection. However, no alterations of these parameters were observed 2 h after injection. In contrast, no significant differences were found in the activities of succinate dehydrogenase, isocitrate dehydrogenase, electron transfer chain complexes or creatine kinase in rats sacrificed 2 or 24 h after IVA administration. Moreover, IVA injection significantly inhibited Na(+),K(+)-ATPase activity (25%) in cerebral cortex of rats 2 or 24 h after IVA administration, while pre-treatment of rats with creatine completely prevented the inhibitory effects of IVA on Na(+),K(+)-ATPase. In conclusion, in vivo administration of IVA inhibits the citric acid cycle probably through the enzyme citrate synthase, as well as Na(+),K(+)-ATPase, a crucial enzyme responsible for maintaining the basal potential membrane necessary for a normal neurotransmission. It is presumed that inhibition of these activities may be involved in the pathophysiology of the neurological dysfunction of isovaleric academic patients. The present findings are of particular interest because treatment with creatine supplementation may represent a potential novel adjuvant therapeutic strategy in IVAcidemia. PMID:19210957

  4. Creatine kinase MB isoenzyme in dermatomyositis: a noncardiac source

    SciTech Connect

    Larca, L.J.; Coppola, J.T.; Honig, S.

    1981-03-01

    Three patients with polymyositis had elevated serum levels of creatine kinase MB isoenzyme. The presence of this isoenzyme is used extensively to diagnose myocardial infarction, but the isoenzyme is also found in sera of patients with primary muscular and neuromuscular disorders. Researchers studied cardiac function in two of our patients with electrocardiograms, technetium stannous pyrophosphate scanning, and technetium 99m-labeled erythrocyte gated blood pool imaging and in the third patient by postmortem examination. There was no evidence of myocardial involvement to account for the high serum levels of isoenzyme. Creatine kinase MB in the sera of patients with polymyositis does not necessarily indicate myocardial necrosis.

  5. Bioconversion of methane to lactate by an obligate methanotrophic bacterium.

    PubMed

    Henard, Calvin A; Smith, Holly; Dowe, Nancy; Kalyuzhnaya, Marina G; Pienkos, Philip T; Guarnieri, Michael T

    2016-01-01

    Methane is the second most abundant greenhouse gas (GHG), with nearly 60% of emissions derived from anthropogenic sources. Microbial conversion of methane to fuels and value-added chemicals offers a means to reduce GHG emissions, while also valorizing this otherwise squandered high-volume, high-energy gas. However, to date, advances in methane biocatalysis have been constrained by the low-productivity and limited genetic tractability of natural methane-consuming microbes. Here, leveraging recent identification of a novel, tractable methanotrophic bacterium, Methylomicrobium buryatense, we demonstrate microbial biocatalysis of methane to lactate, an industrial platform chemical. Heterologous overexpression of a Lactobacillus helveticus L-lactate dehydrogenase in M. buryatense resulted in an initial titer of 0.06 g lactate/L from methane. Cultivation in a 5 L continuously stirred tank bioreactor enabled production of 0.8 g lactate/L, representing a 13-fold improvement compared to the initial titer. The yields (0.05 g lactate/g methane) and productivity (0.008 g lactate/L/h) indicate the need and opportunity for future strain improvement. Additionally, real-time analysis of methane utilization implicated gas-to-liquid transfer and/or microbial methane consumption as process limitations. This work opens the door to develop an array of methanotrophic bacterial strain-engineering strategies currently employed for biocatalytic sugar upgrading to "green" chemicals and fuels. PMID:26902345

  6. Bioconversion of methane to lactate by an obligate methanotrophic bacterium

    PubMed Central

    Henard, Calvin A.; Smith, Holly; Dowe, Nancy; Kalyuzhnaya, Marina G.; Pienkos, Philip T.; Guarnieri, Michael T.

    2016-01-01

    Methane is the second most abundant greenhouse gas (GHG), with nearly 60% of emissions derived from anthropogenic sources. Microbial conversion of methane to fuels and value-added chemicals offers a means to reduce GHG emissions, while also valorizing this otherwise squandered high-volume, high-energy gas. However, to date, advances in methane biocatalysis have been constrained by the low-productivity and limited genetic tractability of natural methane-consuming microbes. Here, leveraging recent identification of a novel, tractable methanotrophic bacterium, Methylomicrobium buryatense, we demonstrate microbial biocatalysis of methane to lactate, an industrial platform chemical. Heterologous overexpression of a Lactobacillus helveticus L-lactate dehydrogenase in M. buryatense resulted in an initial titer of 0.06 g lactate/L from methane. Cultivation in a 5 L continuously stirred tank bioreactor enabled production of 0.8 g lactate/L, representing a 13-fold improvement compared to the initial titer. The yields (0.05 g lactate/g methane) and productivity (0.008 g lactate/L/h) indicate the need and opportunity for future strain improvement. Additionally, real-time analysis of methane utilization implicated gas-to-liquid transfer and/or microbial methane consumption as process limitations. This work opens the door to develop an array of methanotrophic bacterial strain-engineering strategies currently employed for biocatalytic sugar upgrading to “green” chemicals and fuels. PMID:26902345

  7. Bioconversion of methane to lactate by an obligate methanotrophic bacterium

    DOE PAGESBeta

    Henard, Calvin A.; Smith, Holly; Dowe, Nancy; Kalyuzhnaya, Marina G.; Pienkos, Philip T.; Guarnieri, Michael T.

    2016-02-23

    Methane is the second most abundant greenhouse gas (GHG), with nearly 60% of emissions derived from anthropogenic sources. Microbial conversion of methane to fuels and value-added chemicals offers a means to reduce GHG emissions, while also valorizing this otherwise squandered high-volume, high-energy gas. However, to date, advances in methane biocatalysis have been constrained by the low-productivity and limited genetic tractability of natural methane-consuming microbes. Here, leveraging recent identification of a novel, tractable methanotrophic bacterium, Methylomicrobium buryatense, we demonstrate microbial biocatalysis of methane to lactate, an industrial platform chemical. Heterologous overexpression of a Lactobacillus helveticus L-lactate dehydrogenase in M. buryatense resultedmore » in an initial titer of 0.06 g lactate/L from methane. Cultivation in a 5 L continuously stirred tank bioreactor enabled production of 0.8 g lactate/L, representing a 13-fold improvement compared to the initial titer. The yields (0.05 g lactate/g methane) and productivity (0.008 g lactate/L/h) indicate the need and opportunity for future strain improvement. Additionally, real-time analysis of methane utilization implicated gas-to-liquid transfer and/or microbial methane consumption as process limitations. This work opens the door to develop an array of methanotrophic bacterial strain-engineering strategies currently employed for biocatalytic sugar upgrading to “green” chemicals and fuels.« less

  8. A buffered form of creatine does not promote greater changes in muscle creatine content, body composition, or training adaptations than creatine monohydrate

    PubMed Central

    2012-01-01

    Background Creatine monohydrate (CrM) has been consistently reported to increase muscle creatine content and improve high-intensity exercise capacity. However, a number of different forms of creatine have been purported to be more efficacious than CrM. The purpose of this study was to determine if a buffered creatine monohydrate (KA) that has been purported to promote greater creatine retention and training adaptations with fewer side effects at lower doses is more efficacious than CrM supplementation in resistance-trained individuals. Methods In a double-blind manner, 36 resistance-trained participants (20.2 ± 2 years, 181 ± 7 cm, 82.1 ± 12 kg, and 14.7 ± 5% body fat) were randomly assigned to supplement their diet with CrM (Creapure® AlzChem AG, Trostberg, Germany) at normal loading (4 x 5 g/d for 7-days) and maintenance (5 g/d for 21-days) doses; KA (Kre-Alkalyn®, All American Pharmaceutical, Billings, MT, USA) at manufacturer’s recommended doses (KA-L, 1.5 g/d for 28-days); or, KA with equivalent loading (4 x 5 g/d for 7-days) and maintenance (5 g/d) doses of CrM (KA-H). Participants were asked to maintain their current training programs and record all workouts. Muscle biopsies from the vastus lateralis, fasting blood samples, body weight, DEXA determined body composition, and Wingate Anaerobic Capacity (WAC) tests were performed at 0, 7, and 28-days while 1RM strength tests were performed at 0 and 28-days. Data were analyzed by a repeated measures multivariate analysis of variance (MANOVA) and are presented as mean ± SD changes from baseline after 7 and 28-days, respectively. Results Muscle free creatine content obtained in a subgroup of 25 participants increased in all groups over time (1.4 ± 20.7 and 11.9 ± 24.0 mmol/kg DW, p = 0.03) after 7 and 28-days, respectively, with no significant differences among groups (KA-L −7.9 ± 22.3, 4.7 ± 27.0; KA-H 1.0 ± 12.8, 9.1 ± 23.2; CrM 11.3 ± 23.9, 22.3 ± 21.0 mmol/kg DW, p = 0.46). However, while no overall group differences were observed (p = 0.14), pairwise comparison between the KA-L and CrM groups revealed that changes in muscle creatine content tended to be greater in the CrM group (KA-L −1.1 ± 4.3, CrM 11.2 ± 4.3 mmol/kg DW, p = 0.053 [mean ± SEM]). Although some significant time effects were observed, no significant group x time interactions (p > 0.05) were observed in changes in body mass, fat free mass, fat mass, percent body fat, or total body water; bench press and leg press 1RM strength; WAC mean power, peak power, or total work; serum blood lipids, markers of catabolism and bone status, and serum electrolyte status; or, whole blood makers of lymphocytes and red cells. Serum creatinine levels increased in all groups (p < 0.001) with higher doses of creatine promoting greater increases in serum creatinine (p = 0.03) but the increases observed (0.1 – 0.2 mg/dl) were well within normal values for active individuals (i.e., <1.28 ± 0.2 mg/dl). Serum LDL was decreased to a greater degree following ingesting loading doses in the CrM group but returned to baseline during the maintenance phase. No side effects were reported. Conclusions Neither manufacturers recommended doses of KA (1.5 g/d) or KA with equivalent loading (20 g/d for 7-days) and maintenance doses (5 g/d for 21-days) of CrM promoted greater changes in muscle creatine content, body composition, strength, or anaerobic capacity than CrM (20 g/d for 7-days, 5 g/d for 21-days). There was no evidence that supplementing the diet with a buffered form of creatine resulted in fewer side effects than CrM. These findings do not support claims that consuming a buffered form of creatine is a more efficacious and/or safer form of creatine to consume than creatine monohydrate. PMID:22971354

  9. Cryobaroenzymic studies as a tool for investigating activated complexes: creatine kinase.ADP.Mg.nitrate.creatine as a model.

    PubMed

    Balny, C; Travers, F; Barman, T; Douzou, P

    1985-11-01

    By combining cryoenzymology with baroenzymology (a technique we term "cryobaroenzymology") one can obtain "stop-action" pictures of the intermediates in an enzyme reaction pathway and then observe their structural and energetic features ("motion features"). We illustrate the potential of this approach by considering the formation of a transient state analogue complex of creatine kinase (ATP:creatine N-phosphotransferase, EC 2.7.3.2): enzyme.ADP.nitrate.creatine, where nitrate mimics the transferable gamma-phosphate of ATP. Formation of the analogue complex is accompanied by a conformational change that manifests itself by tryptophan perturbation and thus allows kinetic studies by the stopped-flow method. We studied the formation of the analogue complex under cryoenzymic conditions as a function of pressure and solvent composition. This allowed a detailed description of the structural and energetic features of the activation process of an elementary step in an enzyme pathway. PMID:3865173

  10. A creatine-driven substrate cycle enhances energy expenditure and thermogenesis in beige fat.

    PubMed

    Kazak, Lawrence; Chouchani, Edward T; Jedrychowski, Mark P; Erickson, Brian K; Shinoda, Kosaku; Cohen, Paul; Vetrivelan, Ramalingam; Lu, Gina Z; Laznik-Bogoslavski, Dina; Hasenfuss, Sebastian C; Kajimura, Shingo; Gygi, Steve P; Spiegelman, Bruce M

    2015-10-22

    Thermogenic brown and beige adipose tissues dissipate chemical energy as heat, and their thermogenic activities can combat obesity and diabetes. Herein the functional adaptations to cold of brown and beige adipose depots are examined using quantitative mitochondrial proteomics. We identify arginine/creatine metabolism as a beige adipose signature and demonstrate that creatine enhances respiration in beige-fat mitochondria when ADP is limiting. In murine beige fat, cold exposure stimulates mitochondrial creatine kinase activity and induces coordinated expression of genes associated with creatine metabolism. Pharmacological reduction of creatine levels decreases whole-body energy expenditure after administration of a β3-agonist and reduces beige and brown adipose metabolic rate. Genes of creatine metabolism are compensatorily induced when UCP1-dependent thermogenesis is ablated, and creatine reduction in Ucp1-deficient mice reduces core body temperature. These findings link a futile cycle of creatine metabolism to adipose tissue energy expenditure and thermal homeostasis. PAPERCLIP. PMID:26496606

  11. Creatine Loading, Resistance Exercise Performance, and Muscle Mechanics.

    ERIC Educational Resources Information Center

    Stevenson, Scott W.; Dudley, Gary A.

    2001-01-01

    Examined whether creatine (CR) monohydrate loading would alter resistance exercise performance, isometric strength, or in vivo contractile properties of the quadriceps femoris muscle compared with placebo loading in resistance-trained athletes. Overall, CR loading did not provide an ergogenic benefit for the unilateral dynamic knee extension…

  12. Creatine Loading, Resistance Exercise Performance, and Muscle Mechanics.

    ERIC Educational Resources Information Center

    Stevenson, Scott W.; Dudley, Gary A.

    2001-01-01

    Examined whether creatine (CR) monohydrate loading would alter resistance exercise performance, isometric strength, or in vivo contractile properties of the quadriceps femoris muscle compared with placebo loading in resistance-trained athletes. Overall, CR loading did not provide an ergogenic benefit for the unilateral dynamic knee extension

  13. Effect of creatine supplementation on physical performance are related to the AMPD1 and PPARG genes polymorphisms in football players.

    PubMed

    Lifanov, D; Khadyeva, M N; Rahmatullina, L Sh; Demenev, S V; Ibragimov, R R

    2014-06-01

    The aim of this study was to evaluate the effects of short-term creatine supplementation on exercise performance in male athletes depending on the studied genotypes. The present study was limited as long as to two common polymorphisms, such as C34T AMPD1 and Pro12Ala PPARG, selected because previously reported these associations with various aspects of metabolic abnormalities. Athletes had significantly higher frequency of T allele compared to controls AMPD1 34T (7.9 vs. 15.6 %, p < 0.0001) and PPARG 12Ala allele compared to controls (20.7 vs. 15.8%, p < 0.0001). During the experimental period, 21 football players were randomly assigned to either creatine (n = 11) or a dextrose (placebo) (n = 10) supplementation groups. The best response to creatine was presented by AMPD1 CC genotype. Increases in relative VO2(max) values were a significantly (p = 0.052) higher in AMPD1 CT genotype carriers (n = 3; 2.94 ± 0.59 mL x kg(-1) x min(-1)) than AMPD1 CC genotype carriers (n = 8; 0.03 ± 0.01 mL x kg(-1) x min(-1)). We found decrease blood lactate accumulation (La(max)) in AMPD1 CT genotype by 0.84 ± 0.05 mmol x L(-1), and increase by 0.63 ± 0.17 mmol x L(-1) (p = 0.034) in AMPD1 CC genotype. PMID:25665401

  14. Reference values of blood parameters in beef cattle of different ages and stages of lactation.

    PubMed Central

    Doornenbal, H; Tong, A K; Murray, N L

    1988-01-01

    Reference (normal) values for 12 blood serum components were determined for 48 Shorthorn cows (2-10 years old) and their 48 calves, 357 crossbred cows (12-14 years old), 36 feedlot bulls and 36 feedlot steers. In addition, hemoglobin, hematocrit, triiodothyronine, thyroxine and cortisol levels were determined for the crossbred cows, and feedlot bulls and steers. Reference values were tabulated according to sex, age and stage of lactation. Serum concentrations of urea, total protein and bilirubin, and serum activity of aspartate aminotransferase and lactate dehydrogenase increased with age (P less than 0.05), while calcium, phosphorus and alkaline phosphatase decreased with age (P less than 0.05) from birth to the age of ten years. The Shorthorn cows had the highest levels of glucose at parturition (P less than 0.05) with decreasing levels during lactation. Creatinine concentration decreased during lactation and increased during postweaning. Both lactate dehydrogenase and aspartate aminotransferase levels increased (P less than 0.05) during lactation. Urea and uric acid were present at higher concentrations in lactating than nonlactating cows (P less than 0.05). The values reported, based on a wide age range and large number of cattle, could serve as clinical guides and a basis for further research. PMID:3349406

  15. Lactate: Friend or Foe.

    PubMed

    Hall, Mederic M; Rajasekaran, Sathish; Thomsen, Timothy W; Peterson, Andrew R

    2016-03-01

    Lactic acid has played an important role in the traditional theory of muscle fatigue and limitation of endurance exercise performance. It has been called a waste product of anaerobic metabolism and has been believed to be responsible for the uncomfortable "burn" of intense exercise and directly responsible for the metabolic acidosis of exercise, leading to decreased muscle contractility and ultimately cessation of exercise. Although this premise has been commonly taught, it is not supported by the scientific literature and has led to a great deal of confusion among the sports medicine and exercise science communities. This review will provide the sports medicine clinician with an understanding of contemporary lactate theories, including lactate's role in energy production, its contributions to metabolic acidosis, and its function as an energy substrate for a variety of tissues. Lactate threshold concepts will also be discussed, including a practical approach to understanding prediction of performance and monitoring of training progress based on these parameters. PMID:26972271

  16. Effect of limb restraints on serum creatine phosphokinase activity in normal volunteers.

    PubMed

    Goode, D J; Weinberg, D H; Mazura, T A; Curtiss, G; Moretti, R J; Meltzer, H Y

    1977-12-01

    Increased serum creatine phosphokinase (CPK) activity is sometimes found in acutely psychotic patients. In order to study factors affecting CPK activity, we investigated in normal subjects the effect on serum CPK activity of resistance to being restrained and to struggle against leather limb restraints (LLR) sometimes used for control of assaultive of self-destructive behavior of psychiatric patients. Blood samples were obtained 24 hr and immediately before restraint; and immediately, 6, 24, 48, and 72 hr after restraint. Serum CPK activity increases ranged from 3 to 16 times base line levels for all subjects. These increases exceeded the 95% upper limit of normal. Serum pyruvate kinase (PK) activity also increased significantly. In a second study, five male subjects were passively placed in LLR and then struggled against LLR for 1 hr. Serum CPK activity also increased significantly under these conditions, but less than after being forcibly restrained. Serum PK activity and lactic dehydrogenase activity also increased significantly, but serum aspartate aminotransferase (SGOT) activity did not. Since serum CPK activity is increased well above the normal limits in normal subjects after struggle against LLR, studies of serum CPK activity in psychotic patients must avoid the use of restraints as well as other types of trauma, which may produce serum CPK increases persisting as long as 72 hr. PMID:597527

  17. Contraception in lactating women.

    PubMed

    Díaz, S; Croxatto, H B

    1993-12-01

    Lactating women need contraception after first menses, supplementation or 6 months postpartum, or before, according to personal or programmatic reasons. Non-hormonal methods have no influence on lactation and are the first choice. Intrauterine devices (IUDs) inserted during amenorrhea are safe and show good continuation rates. Progestin-only methods do not affect breast-feeding and should be used after 6 weeks to prevent transference of orally active steroids to the newborn. Progesterone rings and Nestorone implants are effective new methods, that use orally inactive steroids. PMID:8286695

  18. Properties of Alanine Dehydrogenase and Aspartase from Propionibacterium freudenreichii subsp. shermanii

    PubMed Central

    Crow, Vaughan L.

    1987-01-01

    During lactate fermentation by Propionibacterium freudenreichii subsp. shermanii ATCC 9614, the only amino acid metabolized was aspartate. After lactate exhaustion, alanine was one of the two amino acids to be metabolized. For every 3 mol of alanine metabolized, 2 mol of propionate, 1 mol each of acetate and CO2, and 3 mol of ammonia were formed. The specific activity of alanine dehydrogenase was 0.08 U/mg of protein during lactate fermentation, and it increased to 0.9 U/mg of protein after lactate exhaustion. Alanine dehydrogenase and aspartase, key enzymes in the metabolism of alanine and aspartate, respectively, were partially purified, and some of their properties were studied. Alanine dehydrogenase had a pH optimum of 9.2 to 9.6 and high Km values for both NAD+ (1 to 4 mM) and alanine (7 to 20 mM). Activity was inhibited by low concentrations of pyruvate and NADH. The pH optimum of aspartase decreased from ∼7.5 to ∼6.4 when the MgCl2 and aspartate concentrations were decreased. Plots of aspartate concentration versus activity showed either hyperbolic or sigmoidal kinetics (interaction coefficient, up to a value of 3.1), depending on pH and MgCl2 concentration. MgCl2 was either an activator or an inhibitor, depending on pH and its concentration. Aspartase activity was inhibited by low concentrations of fumarate. The properties of alanine dehydrogenase and aspartase are consistent with the finding that aspartate is metabolized during lactate fermentation, while alanine is only fermented after lactate exhaustion and then at a slow rate. PMID:16347414

  19. Synthesis of guanidinoacetate and creatine from amino acids by rat pancreas.

    PubMed

    da Silva, Robin P; Clow, Kathy; Brosnan, John T; Brosnan, Margaret E

    2014-02-01

    Creatine is an important molecule involved in cellular energy metabolism. Creatine is spontaneously converted to creatinine at a rate of 1·7% per d; creatinine is lost in the urine. Creatine can be obtained from the diet or synthesised from endogenous amino acids via the enzymes arginine:glycine amidinotransferase (AGAT) and guanidinoacetate N-methyltransferase (GAMT). The liver has high GAMT activity and the kidney has high AGAT activity. Although the pancreas has both AGAT and GAMT activities, its possible role in creatine synthesis has not been characterised. In the present study, we examined the enzymes involved in creatine synthesis in the pancreas as well as the synthesis of guanidinoacetate (GAA) and creatine by isolated pancreatic acini. We found significant AGAT activity and somewhat lower GAMT activity in the pancreas and that pancreatic acini had measurable activities of both AGAT and GAMT and the capacity to synthesise GAA and creatine from amino acids. Creatine supplementation led to a decrease in AGAT activity in the pancreas, though it did not affect its mRNA or protein abundance. This was in contrast with the reduction of AGAT activity and mRNA and protein abundance in the kidney, suggesting that the regulatory mechanisms that control the expression of this enzyme in the pancreas are different from those in the kidney. Dietary creatine increased the concentrations of GAA, creatine and phosphocreatine in the pancreas. Unexpectedly, creatine supplementation decreased the concentrations of S-adenosylmethionine, while those of S-adenosylhomocysteine were not altered significantly. PMID:24103317

  20. Creatine protects against mitochondrial dysfunction associated with HIV-1 Tat-induced neuronal injury

    PubMed Central

    Stevens, Patrick R.; Gawryluk, Jeremy W.; Hui, Liang; Chen, Xuesong; Geiger, Jonathan D.

    2015-01-01

    HIV-1 infected individuals are living longer but experiencing a prevalence rate of over 50% for HIV-1 associated neurocognitive disorders (HAND) for which no effective treatment is available. Viral and cellular factors secreted by HIV-1 infected cells leads to neuronal injury and HIV-1 Tat continues to be implicated in the pathogenesis of HAND. Here we tested the hypothesis that creatine protected against HIV-1 Tat-induced neuronal injury by preventing mitochondrial bioenergetic crisis and/or redox catastrophe. Creatine blocked HIV-1 Tat1-72-induced increases in neuron cell death and synaptic area loss. Creatine protected against HIV-1 Tat-induced decreases in ATP. Creatine and creatine plus HIV-1 Tat increased cellular levels of creatine, and creatine plus HIV-1 Tat further decreased ratios of phosphocreatine to creatine observed with creatine or HIV-1 Tat treatments alone. Additionally, creatine protected against HIV-1 Tat-induced mitochondrial hypopolarization and HIV-1 Tat-induced mitochondrial permeability transition pore opening. Thus, creatine may be a useful adjunctive therapy against HAND. PMID:25613139

  1. Creatine supplementation spares muscle glycogen during high intensity intermittent exercise in rats

    PubMed Central

    2010-01-01

    Background The effects of creatine (CR) supplementation on glycogen content are still debatable. Thus, due to the current lack of clarity, we investigated the effects of CR supplementation on muscle glycogen content after high intensity intermittent exercise in rats. Methods First, the animals were submitted to a high intensity intermittent maximal swimming exercise protocol to ensure that CR-supplementation was able to delay fatigue (experiment 1). Then, the CR-mediated glycogen sparing effect was examined using a high intensity intermittent sub-maximal exercise test (fixed number of bouts; six bouts of 30-second duration interspersed by two-minute rest interval) (experiment 2). For both experiments, male Wistar rats were given either CR supplementation or placebo (Pl) for 5 days. Results As expected, CR-supplemented animals were able to exercise for a significant higher number of bouts than Pl. Experiment 2 revealed a higher gastrocnemius glycogen content for the CR vs. the Pl group (33.59%). Additionally, CR animals presented lower blood lactate concentrations throughout the intermittent exercise bouts compared to Pl. No difference was found between groups in soleus glycogen content. Conclusion The major finding of this study is that CR supplementation was able to spare muscle glycogen during a high intensity intermittent exercise in rats. PMID:20205834

  2. Lactate does not activate NF-κB in oxidative tumor cells

    PubMed Central

    Van Hée, Vincent F.; Pérez-Escuredo, Jhudit; Cacace, Andrea; Copetti, Tamara; Sonveaux, Pierre

    2015-01-01

    The lactate anion is currently emerging as an oncometabolite. Lactate, produced and exported by glycolytic and glutaminolytic cells in tumors, can be recycled as an oxidative fuel by oxidative tumors cells. Independently of hypoxia, it can also activate transcription factor hypoxia-inducible factor-1 (HIF-1) in tumor and endothelial cells, promoting angiogenesis. These protumoral activities of lactate depend on lactate uptake, a process primarily facilitated by the inward, passive lactate-proton symporter monocarboxylate transporter 1 (MCT1); the conversion of lactate and NAD+ to pyruvate, NADH and H+ by lactate dehydrogenase-1 (LDH-1); and a competition between pyruvate and α-ketoglutarate that inhibits prolylhydroxylases (PHDs). Endothelial cells do not primarily use lactate as an oxidative fuel but, rather, as a signaling agent. In addition to HIF-1, lactate can indeed activate transcription factor nuclear factor-κB (NF-κB) in these cells, through a mechanism not only depending on PHD inhibition but also on NADH alimenting NAD(P)H oxidases to generate reactive oxygen species (ROS). While NF-κB activity in endothelial cells promotes angiogenesis, NF-κB activation in tumor cells is known to stimulate tumor progression by conferring resistance to apoptosis, stemness, pro-angiogenic and metastatic capabilities. In this study, we therefore tested whether exogenous lactate could activate NF-κB in oxidative tumor cells equipped for lactate signaling. We report that, precisely because they are oxidative, HeLa and SiHa human tumor cells do not activate NF-κB in response to lactate. Indeed, while lactate-derived pyruvate is well-known to inhibit PHDs in these cells, we found that NADH aliments oxidative phosphorylation (OXPHOS) in mitochondria rather than NAD(P)H oxidases in the cytosol. These data were confirmed using oxidative human Cal27 and MCF7 tumor cells. This new information positions the malate-aspartate shuttle as a key player in the oxidative metabolism of lactate: similar to glycolysis that aliments OXPHOS with pyruvate produced by pyruvate kinase and NADH produced by glyceraldehyde-3-phosphate dehydrogenase (GAPDH), oxidative lactate metabolism aliments OXPHOS in oxidative tumor cells with pyruvate and NADH produced by LDH1. PMID:26528183

  3. Increased Ventricular Cerebrospinal Fluid Lactate in Depressed Adolescents

    PubMed Central

    Bradley, Kailyn A. L.; Mao, Xiangling; Case, Julia A. C.; Kang, Guoxin; Shungu, Dikoma C.; Gabbay, Vilma

    2016-01-01

    Background Mitochondrial dysfunction has been increasingly examined as a potential pathogenic event in psychiatric disorders, although its role early in the course of major depressive disorder (MDD) is unclear. Therefore, the purpose of this study was to investigate mitochondrial dysfunction in medication-free adolescents with MDD through in vivo measurements of neurometabolites using high-spatial resolution multislice/multivoxel proton magnetic resonance spectroscopy. Methods Twenty-three adolescents with MDD and 29 healthy controls, ages 12–20, were scanned at 3T and concentrations of ventricular cerebrospinal fluid lactate, as well as N-acetyl-aspartate (NAA), total creatine (tCr), and total choline (tCho) in the bilateral caudate, putamen, and thalamus were reported. Results Adolescents with MDD exhibited increased ventricular lactate compared to healthy controls [F(1, 41) = 6.98, p = .01]. However, there were no group differences in the other neurometabolites. Dimensional analyses in the depressed group showed no relation between any of the neurometabolites and symptomatology, including anhedonia and fatigue. Conclusions Increased ventricular lactate in depressed adolescents suggests mitochondrial dysfunction may be present early in the course of MDD; however it is still not known whether the presence of mitochondrial dysfunction is a trait vulnerability of individuals predisposed to psychopathology or a state feature of the disorder. Therefore, there is a need for larger multimodal studies to clarify these chemical findings in the context of network function. PMID:26802978

  4. Diagnostic methods and recommendations for the cerebral creatine deficiency syndromes.

    PubMed

    Clark, Joseph F; Cecil, Kim M

    2015-03-01

    Primary care pediatricians and a variety of specialist physicians strive to define an accurate diagnosis for children presenting with impairment of expressive speech and delay in achieving developmental milestones. Within the past two decades, a group of disorders featuring this presentation have been identified as cerebral creatine deficiency syndromes (CCDS). Patients with these disorders were initially discerned using proton magnetic resonance spectroscopy of the brain within a magnetic resonance imaging (MRI) examination. The objective of this review is to provide the clinician with an overview of the current information available on identifying and treating these conditions. We explain the salient features of creatine metabolism, synthesis, and transport required for normal development. We propose diagnostic approaches for confirming a CCDS diagnosis. Finally, we describe treatment approaches for managing patients with these conditions. PMID:25521922

  5. Assignment of the creatine transporter gene (SLC6A8) to human chromosome Xq28 telomeric to G6PD

    SciTech Connect

    Gregor, P.; Nash, S.R.; Caron, M.G.

    1995-01-01

    The creatine-phosphocreatine shuttle has important functions in the temporal and spatial maintenance of the energy supply to skeletal and cardiac muscle. Muscle cells do not synthesize creatine, but take it up via a specific sodium-dependent transporter - the creatine transporter. Thus, the creatine transporter has an important role in muscular physiology. Furthermore, inhibition of creatine transport in experimental animals causes muscle weakness. Recently, creatine transporter cDNAs have been isolated and characterized from rabbit and human. In this communication we report mapping of the creatine transporter gene to human chromosome Xq28. 12 refs., 1 fig.

  6. Studies of the haemodynamic effects of creatine phosphate in man.

    PubMed Central

    Hurlow, R A; Aukland, A; Hardman, J; Whittington, J R

    1982-01-01

    1 The haemodynamic effects of intravenous creatine phosphate 1000 mg have been studied. 2 During the first 60 min following drug administration heart rate and blood pressure did not change but cardiac output fell significantly by approximately 18%. Calculated total peripheral resistance showed a corresponding significant rise, the maximum increase being approximately 24%. All these changes were beginning to diminish within 90 min after the injection. 3 Total limb blood flow measured in both arm and leg (using venous occlusion strain-gauge plethysmography) showed no appreciable changes following injection of creatine phosphate. 4 There was a progressive reduction in leg muscle blood flow (Xe133 clearance method) following injection which was statistically significant with respect to the initial level and reached a minimum (46% reduction) 50 min after the injection. 5 Skin blood flow, estimated by infra-red photoplethysmography, showed changes complementary to those seen with muscle flow. There was a progressive and significant rise to a peak (73% increase) 30 min after the injection. 6 No adverse reactions to the injections were noted. 7 Reduced cardiac output in the absence of altered total limb blood flow presumably reflects a reduction in visceral blood flow, which was not measured in this study. Within the limbs, creatine phosphate appears to result in a redistribution of blood flow from muscle to skin. Thus, these preliminary results suggest that intravenous creatine phosphate could be clinically useful in situations where short term improvement in skin blood flow would be advantageous and that further controlled studies would be justified. PMID:7093109

  7. Estimation of skeletal muscle mass from body creatine content

    NASA Technical Reports Server (NTRS)

    Pace, N.; Rahlmann, D. F.

    1982-01-01

    Procedures have been developed for studying the effect of changes in gravitational loading on skeletal muscle mass through measurements of the body creatine content. These procedures were developed for studies of gravitational scale effects in a four-species model, comprising the hamster, rat, guinea pig, and rabbit, which provides a sufficient range of body size for assessment of allometric parameters. Since intracellular muscle creatine concentration varies among species, and with age within a given species, the concentration values for metabolically mature individuals of these four species were established. The creatine content of the carcass, skin, viscera, smooth muscle, and skeletal muscle was determined for each species. In addition, the skeletal muscle mass of the major body components was determined, as well as the total and fat-free masses of the body and carcass, and the percent skeletal muscle in each. It is concluded that these procedures are particularly useful for studying the effect of gravitational loading on the skeletal muscle content of the animal carcass, which is the principal weight-bearing organ of the body.

  8. Elevated plasma citrulline: look for dihydrolipoamide dehydrogenase deficiency.

    PubMed

    Haviv, Ruby; Zeharia, Avraham; Belaiche, Corinne; Haimi Cohen, Yishai; Saada, Ann

    2014-02-01

    The E3 subunit of the pyruvate dehydrogenase complex (dihydrolipoamide dehydrogenase/dihydrolipoyl dehydrogenase/DLD/lipoamide dehydrogenase/LAD), is a mitochondrial matrix enzyme and also a part of the branched-chain ketoacid dehydrogenase and alpha-ketoglutarate dehydrogenase complexes. DLD deficiency (MIM #246900), is relatively frequent in the Ashkenazi Jewish population but occurs in other populations as well. Early diagnosis is important to prevent episodes of metabolic decompensation, liver failure, and encephalopathy. The clinical presentations are varied and may include Reye-like syndrome, hepatic failure, myopathy, and myoglobinuria. Laboratory markers, such as elevated urinary alpha-ketoglutarate, blood pyruvate, lactate, and ammonia, are mostly nonspecific and not always present, making the diagnosis difficult. Since we observed elevated plasma citrulline levels in a number of confirmed cases, we retrospectively examined the value of citrulline as a biochemical marker for DLD deficiency. Data was gathered from the files of 17 pediatric patients with DLD deficiency, confirmed by enzymatic and genetic analysis. The control group included 19 patients in whom urea cycle defects were ruled out but DLD deficiency was suspected. Seven of the DLD-deficient patients presented with elevated plasma citrulline levels (median value 205 μM, range 59-282 μM) (normal range 1-45 μM) while none in the control patient group. In five patients, elevated citrulline was associated with elevated plasma glutamine and metabolic acidosis. Interestingly, elevated plasma citrulline was associated with the common G229C mutation. In conclusion, we suggest that elevated plasma citrulline in the absence of urea cycle defects warrants an investigation for DLD deficiency. PMID:23995961

  9. Efficiency of superoxide anions in the inactivation of selected dehydrogenases

    NASA Astrophysics Data System (ADS)

    Rodacka, Aleksandra; Serafin, Eligiusz; Puchala, Mieczyslaw

    2010-09-01

    The most ubiquitous of the primary reactive oxygen species, formed in all aerobes, is the superoxide free radical. It is believed that the superoxide anion radical shows low reactivity and in oxidative stress it is regarded mainly as an initiator of more reactive species such as rad OH and ONOO -. In this paper, the effectiveness of inactivation of selected enzymes by radiation-generated superoxide radicals in comparison with the effectiveness of the other products of water radiolysis is examined. We investigate three enzymes: glyceraldehyde-3-phosphate dehydrogenase (GAPDH), alcohol dehydrogenase (ADH) and lactate dehydrogenase (LDH). We show that the direct contribution of the superoxide anion radical to GAPDH and ADH inactivation is significant. The effectiveness of the superoxide anion in the inactivation of GAPDH and ADG was only 2.4 and 2.8 times smaller, respectively, in comparison with hydroxyl radical. LDH was practically not inactivated by the superoxide anion. Despite the fact that the studied dehydrogenases belong to the same class of enzymes (oxidoreductases), all have a similar molecular weight and are tetramers, their susceptibility to free-radical damage varies. The differences in the radiosensitivity of the enzymes are not determined by the basic structural parameters analyzed. A significant role in inactivation susceptibility is played by the type of amino acid residues and their localization within enzyme molecules.

  10. Cyanobacterial NADPH dehydrogenase complexes

    SciTech Connect

    Ogawa, Teruo; Mi, Hualing

    2007-07-01

    Cyanobacteria possess functionally distinct multiple NADPH dehydrogenase (NDH-1) complexes that are essential to CO2 uptake, photosystem-1 cyclic electron transport and respiration. The unique nature of cyanobacterial NDH-1 complexes is the presence of subunits involved in CO2 uptake. Other than CO2 uptake, chloroplastic NDH-1 complex has similar role as cyanobacterial NDH-1 complexes in photosystem-1 cyclic electron transport and respiration (chlororespiration). In this mini-review we focus on the structure and function of cyanobacterial NDH-1 complexes and their phylogeny. The function of chloroplastic NDH-1 complex and characteristics of plants defective in NDH-1 are also described forcomparison.

  11. Creatine supplementation with specific view to exercise/sports performance: an update

    PubMed Central

    2012-01-01

    Creatine is one of the most popular and widely researched natural supplements. The majority of studies have focused on the effects of creatine monohydrate on performance and health; however, many other forms of creatine exist and are commercially available in the sports nutrition/supplement market. Regardless of the form, supplementation with creatine has regularly shown to increase strength, fat free mass, and muscle morphology with concurrent heavy resistance training more than resistance training alone. Creatine may be of benefit in other modes of exercise such as high-intensity sprints or endurance training. However, it appears that the effects of creatine diminish as the length of time spent exercising increases. Even though not all individuals respond similarly to creatine supplementation, it is generally accepted that its supplementation increases creatine storage and promotes a faster regeneration of adenosine triphosphate between high intensity exercises. These improved outcomes will increase performance and promote greater training adaptations. More recent research suggests that creatine supplementation in amounts of 0.1 g/kg of body weight combined with resistance training improves training adaptations at a cellular and sub-cellular level. Finally, although presently ingesting creatine as an oral supplement is considered safe and ethical, the perception of safety cannot be guaranteed, especially when administered for long period of time to different populations (athletes, sedentary, patient, active, young or elderly). PMID:22817979

  12. The polysome as a terminal for the creatine phosphate energy shuttle.

    PubMed

    Savabi, F; Carpenter, C L; Mohan, C; Bessman, S P

    1988-12-01

    The role of the creatine phosphate shuttle in the energetics of muscle protein synthesis in isolated polysomes, from rat hindlimb muscle, was studied. Triton X-100-treated polysomes, following their centrifugation through a 1 M sucrose gradient, contained 38 mU/mg RNA of bound creatine kinase. In the presence of pH 5 enzyme (obtained from rat liver), 0.5 mM ATP, and 1 microM GTP, amino acid (leucine) incorporation by polysomes in the presence of 8 mM creatine phosphate was twice that in the presence of an exogenous ATP regenerating system of 10 mM phospho(enol)pyruvate and 10 U/ml pyruvate kinase. Since added creatine kinase had no effect on incorporation supported by creatine phosphate it is clear that endogenous creatine kinase allows sufficient regeneration of ATP. These data also suggest that nucleoside diphosphokinase must have been associated with the polysome for phosphate was transferred to GTP from [33P]creatine phosphate, and the specific activities of ATP and GTP increased at equal rates, reaching the specific activity of creatine phosphate at 8 min. We conclude that skeletal muscle polysomes have bound creatine kinase activity and they act as terminals for the creatine phosphate energy shuttle. Creatine phosphate regenerates GTP, probably through an intermediate reaction catalyzed by nucleoside diphosphokinase. This provided an added support for the hypothesis of compartmentation of enzymes and substrates and that the transport form of energy between the mitochondria and energy utilizing sites in muscle is creatine phosphate rather than ATP, which extends the general role of the creatine phosphate energy shuttle. PMID:2852949

  13. High content of creatine kinase in chicken retina: compartmentalized localization of creatine kinase isoenzymes in photoreceptor cells.

    PubMed Central

    Wallimann, T; Wegmann, G; Moser, H; Huber, R; Eppenberger, H M

    1986-01-01

    Two isoforms of creatine kinase (CK; ATP:creatine N-phosphotransferase, E.C. 2.7.3.2), brain type (BB-CK) and mitochondrial type (MiMi-CK), but not the muscle types (MM- or hybrid MB-CK), were identified by cellulose polyacetate electrophoresis and immunoblots in retina from adult chickens. Indirect immunofluorescence labeling of cryosections of retinas revealed high concentrations of BB-CK in both rod and cone photoreceptor cells. Most of the fluorescence staining with anti-B-CK antibodies was found within the myoid and the ellipsoid portions of inner segments and the peripheral region of the outer segments. Significant staining with anti-B-CK antibodies was also found in horizontal cells and in the optical nerve fibers, with additional stratified staining in the inner plexiform layer. MiMi-CK was solely demonstrated in the ellipsoid portion of the photoreceptor cells. The presence of high concentrations of compartmentalized CK isoenzymes within photoreceptor cells (approximately equal to 30 enzyme units/mg) as well as the relatively high concentration of total creatine in these cells (approximately equal to 10-15 mM) indicates an important physiological function for CK and phosphocreatine in the energy transduction of vision. Images PMID:3520556

  14. Postpartum Exercise and Lactation.

    PubMed

    Bane, Susan M

    2015-12-01

    Many women who are breastfeeding also want to participate in exercise, but have concerns about the safety of their newborn. The following chapter reviews issues related to postpartum exercise and lactation. The goals of the chapter are to help clinicians understand the benefits of exercise, examine the impact of postpartum exercise on breastfeeding, and provide practical recommendations for exercise during the postpartum period in women who are breastfeeding. PMID:26398298

  15. Docosahexaenoic acid and lactation.

    PubMed

    Jensen, Craig L; Lapillonne, Alexandre

    2009-01-01

    Docosahexaenoic acid (DHA) is an important component of membrane phospholipids in the retina and brain and accumulates rapidly in these tissues during early infancy. DHA is present in human milk, but the amount varies considerably and is largely dependent on maternal diet. This article reviews data addressing the impact of different DHA intakes by lactating women on infant and maternal outcomes to determine if available data are sufficient to estimate optimal breast milk DHA content and estimate dietary reference intakes (DRIs) for DHA by breast-feeding mothers. Results of published observational studies and interventional trials assessing the impact of maternal DHA intake (or breast milk DHA content) on infant visual function, neurodevelopment, and immunologic status were reviewed. Studies related to the potential impact of DHA intake on depression or cognitive function of lactating women also were reviewed. Although only a limited number of studies are available in the current medical literature, and study results have not been consistent, better infant neurodevelopment and/or visual function have been reported with higher vs. lower levels of breast milk DHA. The effect of DHA intake on the incidence or severity of depression in lactating women is not clear. Increasing breast milk DHA content above that typically found in the US, by increasing maternal DHA intake, may confer neurodevelopmental benefits to the recipient breast-fed infant. However, current data are insufficient to permit determination of specific DRIs during this period. PMID:19632101

  16. Effect of oral creatine supplementation on human muscle GLUT4 protein content after immobilization.

    PubMed

    Op 't Eijnde, B; Ursø, B; Richter, E A; Greenhaff, P L; Hespel, P

    2001-01-01

    The purpose of this study was to investigate the effect of oral creatine supplementation on muscle GLUT4 protein content and total creatine and glycogen content during muscle disuse and subsequent training. A double-blind placebo-controlled trial was performed with 22 young healthy volunteers. The right leg of each subject was immobilized using a cast for 2 weeks, after which subjects participated in a 10-week heavy resistance training program involving the knee-extensor muscles (three sessions per week). Half of the subjects received creatine monohydrate supplements (20 g daily during the immobilization period and 15 and 5 g daily during the first 3 and the last 7 weeks of rehabilitation training, respectively), whereas the other 11 subjects ingested placebo (maltodextrine). Muscle GLUT4 protein content and glycogen and total creatine concentrations were assayed in needle biopsy samples from the vastus lateralis muscle before and after immobilization and after 3 and 10 weeks of training. Immobilization decreased GLUT4 in the placebo group (-20%, P < 0.05), but not in the creatine group (+9% NS). Glycogen and total creatine were unchanged in both groups during the immobilization period. In the placebo group, during training, GLUT4 was normalized, and glycogen and total creatine were stable. Conversely, in the creatine group, GLUT4 increased by approximately 40% (P < 0.05) during rehabilitation. Muscle glycogen and total creatine levels were higher in the creatine group after 3 weeks of rehabilitation (P < 0.05), but not after 10 weeks of rehabilitation. We concluded that 1) oral creatine supplementation offsets the decline in muscle GLUT4 protein content that occurs during immobilization, and 2) oral creatine supplementation increases GLUT4 protein content during subsequent rehabilitation training in healthy subjects. PMID:11147785

  17. The Effect of L-Arginine and Creatine on Vascular Function and Homocysteine Metabolism

    PubMed Central

    Jahangir, Eiman; Vita, Joseph A.; Handy, Diane; Holbrook, Monica; Palmisano, Joseph; Beal, Ryan; Loscalzo, Joseph; Eberhardt, Robert T.

    2010-01-01

    Background Studies with L-arginine supplementation have shown inconsistent effects on endothelial function. The generation of guanidinoacetate (GAA) from L-arginine with subsequent formation of creatine and homocysteine and consumption of methionine may reduce the pool of L-arginine available for nitric oxide generation. Experimental studies suggest that creatine supplementation might block this pathway. We sought to determine the effects of L-arginine, creatine, or the combination on endothelium-dependent vasodilation and homocysteine metabolism in patients with coronary artery disease. Methods Patients with coronary artery disease were randomized to L-arginine (9gm/day), creatine (21gm/day), L-arginine plus creatine, or placebo for 4 days (n=26–29/group). Brachial artery flow-mediated dilation and plasma levels of L-arginine, creatine, homocysteine, methionine, and GAA were measured at baseline and follow up. Results L-arginine and creatine supplementation had no effects on vascular function. L-arginine alone increased GAA (P<0.01) and the ratio of homocysteine to methionine (P<0.01) suggesting increased methylation demand. The combination of creatinine and L-arginine did not suppress GAA production or prevent the increase in homocysteine-to-methionine ratio. Unexpectedly, creatine supplementation (alone or in combination with L-arginine) was associated with an 11 to 20% increase in homocysteine concentration (P<0.05), which was not attributable to worsened renal function, providing evidence against an effect of creatine on decreasing methylation demand. Conclusion The present study provides no evidence that L-arginine supplementation improves endothelial function and suggests that L-arginine may increase methylation demand. Creatine supplementation failed to alter the actions of L-arginine on vascular function or suppress methylation demand. The unexpected increase in homocysteine levels following creatine supplementation could have adverse effects and merits further study, since creatine is a commonly used dietary supplement. PMID:19651674

  18. Creatine supplementation enhances corticomotor excitability and cognitive performance during oxygen deprivation.

    PubMed

    Turner, Clare E; Byblow, Winston D; Gant, Nicholas

    2015-01-28

    Impairment or interruption of oxygen supply compromises brain function and plays a role in neurological and neurodegenerative conditions. Creatine is a naturally occurring compound involved in the buffering, transport, and regulation of cellular energy, with the potential to replenish cellular adenosine triphosphate without oxygen. Creatine is also neuroprotective in vitro against anoxic/hypoxic damage. Dietary creatine supplementation has been associated with improved symptoms in neurological disorders defined by impaired neural energy provision. Here we investigate, for the first time in humans, the utility of creatine as a dietary supplement to protect against energetic insult. The aim of this study was to assess the influence of oral creatine supplementation on the neurophysiological and neuropsychological function of healthy young adults during acute oxygen deprivation. Fifteen healthy adults were supplemented with creatine and placebo treatments for 7 d, which increased brain creatine on average by 9.2%. A hypoxic gas mixture (10% oxygen) was administered for 90 min, causing global oxygen deficit and impairing a range of neuropsychological processes. Hypoxia-induced decrements in cognitive performance, specifically attentional capacity, were restored when participants were creatine supplemented, and corticomotor excitability increased. A neuromodulatory effect of creatine via increased energy availability is presumed to be a contributing factor of the restoration, perhaps by supporting the maintenance of appropriate neuronal membrane potentials. Dietary creatine monohydrate supplementation augments neural creatine, increases corticomotor excitability, and prevents the decline in attention that occurs during severe oxygen deficit. This is the first demonstration of creatine's utility as a neuroprotective supplement when cellular energy provision is compromised. PMID:25632150

  19. The effects of creatine supplementation on selected factors of tennis specific training

    PubMed Central

    Pluim, B M; Ferrauti, A; Broekhof, F; Deutekom, M; Gotzmann, A; Kuipers, H; Weber, K

    2006-01-01

    Background Creatine supplementation is popular among tennis players but it is not clear whether it actually enhances tennis performance. Objectives To examine the effects of creatine supplementation on tennis specific performance indices. Methods In a randomised, double blind design, 36 competitive male tennis players (24 creatine, mean (SD) age, 22.5 (4.9) years; 12 placebo, 22.8 (4.8) years) were tested at baseline, after six days of creatine loading, and after a maintenance phase of four weeks (14 creatine, 10 placebo). Serving velocity (10 serves), forehand and backhand velocity (three series of 5×8 strokes), arm and leg strength (bench press and leg press), and intermittent running speed (three series of five 20 metre sprints) were measured. Results Compared with placebo, neither six days nor five weeks of creatine supplementation had a significant effect on serving velocity (creatine: +2 km/h; placebo: +2 km/h, p = 0.90); forehand velocity (creatine: +4 km/h; placebo: +4 km/h, p = 0.80), or backhand velocity (creatine: +3 km/h; placebo: +1 km/h, p = 0.38). There was also no significant effect of creatine supplementation on repetitive sprint power after 5, 10, and 20 metres, (creatine 20 m: −0.03 m/s; placebo 20 m: +0.01 m/s, p = 0.18), or in the strength of the upper and lower extremities. Conclusions Creatine supplementation is not effective in improving selected factors of tennis specific performance and should not be recommended to tennis players. PMID:16720886

  20. Measurement of lactate formation from glucose using (6- sup 3 H)- and (6- sup 14 C)glucose in humans

    SciTech Connect

    Virkamaeki, A.P.; Puhakainen, I.; Nurjhan, N.; Gerich, J.E.; Yki-Jaervinen, H. )

    1990-09-01

    To assess the validity of determining the origin of plasma lactate from the ratio of lactate and glucose specific activities (SA) during infusion of labeled glucose, normal subjects received infusions of (6-3H)- and (6-14C)glucose for 4 h after a 12 h fast, and, on another day, cold glucose labeled with both tracers during 4-6 h of hyperinsulinemia (approximately 650 microU/ml). Basally, less lactate was derived from plasma glucose when measured with (6-3H)glucose (27 +/- 2%) than with (6-14C)glucose (40 +/- 2%, P less than 0.001). Insulin did not increase the percent of lactate derived from plasma glucose when measured with (6-3H)glucose (29 +/- 2%) but did increase when measured with (6-14C)glucose (60 +/- 4%). The arterialized blood (A) (3H)lactate SA was 30-40% higher (P less than 0.01) than deep venous blood (V) (3H)lactate SA, whereas A and V (14C)lactate SA were similar. During conversion of alanine to lactate with glutamic-pyruvic transaminase (GPT) and lactate dehydrogenase (LDH) in vitro, 32 +/- 2% of 3H in (3-3H)alanine was found in water and 68 +/- 2% in lactate. During infusion of (6-3H)- and (6-14C)glucose, the ratio of (14C)alanine to lactate SA (0.88 +/- 0.05) was less than the ratio of (3H)alanine to lactate SA (0.31 +/- 0.03, P less than 0.001). In conclusion (1) loss of 3H relative to 14C from position 6 in glucose occurs during lactate formation in extrahepatic tissues possibly due to the GPT reaction (alanine conversion to pyruvate), and (2) even under supraphysiologic hyperinsulinemic conditions not all of plasma lactate originates from plasma glucose.

  1. Blocking Lactate Export by Inhibiting the Myc Target MCT1 Disables Glycolysis and Glutathione Synthesis

    PubMed Central

    Doherty, Joanne R.; Yang, Chunying; Scott, Kristen E. N.; Cameron, Michael D.; Fallahi, Mohammad; Li, Weimin; Hall, Mark A.; Amelio, Antonio L.; Mishra, Jitendra K.; Li, Fangzheng; Tortosa, Mariola; Genau, Heide Marika; Rounbehler, Robert J.; Lu, Yunqi; Dang, Chi. V.; Kumar, K. Ganesh; Butler, Andrew A.; Bannister, Thomas D.; Hooper, Andrea T.; Unsal-Kacmaz, Keziban; Roush, William R.; Cleveland, John L.

    2014-01-01

    Myc oncoproteins induce genes driving aerobic glycolysis, including lactate dehydrogenase-A that generates lactate. Here we report that Myc controls transcription of the lactate transporter SLC16A1/MCT1, and that elevated MCT1 levels are manifest in premalignant and neoplastic Eμ-Myc transgenic B cells and in human malignancies with MYC or MYCN involvement. Notably, disrupting MCT1 function leads to an accumulation of intracellular lactate that rapidly disables tumor cell growth and glycolysis, provoking marked alterations in glycolytic intermediates, and reductions in glucose transport, and in levels of ATP, NADPH and glutathione. Reductions in glutathione then lead to increases in hydrogen peroxide, mitochondrial damage and, ultimately, cell death. Finally, forcing glycolysis by metformin treatment augments this response and the efficacy of MCT1 inhibitors, suggesting an attractive combination therapy for MYC/MCT1-expressing malignancies. PMID:24285728

  2. Blocking lactate export by inhibiting the Myc target MCT1 Disables glycolysis and glutathione synthesis.

    PubMed

    Doherty, Joanne R; Yang, Chunying; Scott, Kristen E N; Cameron, Michael D; Fallahi, Mohammad; Li, Weimin; Hall, Mark A; Amelio, Antonio L; Mishra, Jitendra K; Li, Fangzheng; Tortosa, Mariola; Genau, Heide Marika; Rounbehler, Robert J; Lu, Yunqi; Dang, Chi V; Kumar, K Ganesh; Butler, Andrew A; Bannister, Thomas D; Hooper, Andrea T; Unsal-Kacmaz, Keziban; Roush, William R; Cleveland, John L

    2014-02-01

    Myc oncoproteins induce genes driving aerobic glycolysis, including lactate dehydrogenase-A that generates lactate. Here, we report that Myc controls transcription of the lactate transporter SLC16A1/MCT1 and that elevated MCT1 levels are manifest in premalignant and neoplastic Eμ-Myc transgenic B cells and in human malignancies with MYC or MYCN involvement. Notably, disrupting MCT1 function leads to an accumulation of intracellular lactate that rapidly disables tumor cell growth and glycolysis, provoking marked alterations in glycolytic intermediates, reductions in glucose transport, and in levels of ATP, NADPH, and ultimately, glutathione (GSH). Reductions in GSH then lead to increases in hydrogen peroxide, mitochondrial damage, and ultimately, cell death. Finally, forcing glycolysis by metformin treatment augments this response and the efficacy of MCT1 inhibitors, suggesting an attractive combination therapy for MYC/MCT1-expressing malignancies. PMID:24285728

  3. Age dependence of myosin heavy chain transitions induced by creatine depletion in rat skeletal muscle

    NASA Technical Reports Server (NTRS)

    Adams, Gregory R.; Baldwin, Kenneth M.

    1995-01-01

    This study was designed to test the hypothesis that myosin heavy chain (MHC) plasticity resulting from creatine depletion is an age-dependent process. At weaning (age 28 days), rat pups were placed on either standard rat chow (normal diet juvenile group) or the same chow supplemented with 1% wt/wt of the creatine analogue beta-guanidinopropionic acid (creatine depletion juvenile (CDJ) group). Two groups of adult rats (age approximately 8 wk) were placed on the same diet regimens (normal diet adult and creatine depletion adult (CDA) groups). After 40 days (CDJ and normal diet juvenile groups) and 60 days (CDA and normal diet adult groups), animals were killed and several skeletal muscles were removed for analysis of creatine content or MHC ditribution. In the CDJ group, creatine depletion (78%) was accompanied by significant shifts toward expression of slower MHC isoforms in two slow and three fast skeletal muscles. In contrast, creatine depletion in adult animals did not result in similar shifts toward slow MHC isoform expression in either muscle type. The results of this study indicate that there is a differential effect of creatine depletion on MHC tranitions that appears to be age dependent. These results strongly suggest that investigators contemplating experimental designs involving the use of the creatine analogue beta-guanidinopropionic acid should consider the age of the animals to be used.

  4. Creatine kinase and mitochondrial respiration in hearts of trout, cod and freshwater turtle.

    PubMed

    Birkedal, R; Gesser, H

    2003-08-01

    The importance of the creatine kinase system in the cardiac muscle of ectothermic vertebrates is unclear. Mammalian cardiac muscle seems to be structurally organized in a manner that compartmentalizes the intracellular environment as evidenced by the substantially higher mitochondrial apparent Km for ADP in skinned fibres compared to isolated mitochondria. A mitochondrial fraction of creatine kinase is functionally coupled to the mitochondrial respiration, and the transport of phosphocreatine and creatine as energy equivalents of ATP and ADP, respectively, increases the mitochondrial apparent ADP affinity, i.e. lowers the Km. This function of creatine kinase seems to be absent in hearts of frog species. To find out whether this applies to hearts of ectothermic vertebrate species in general, we investigated the effect of creatine on the mitochondrial respiration of saponin-skinned fibres from the ventricle of rainbow trout, Atlantic cod and freshwater turtle. For all three species, the apparent Km for ADP appeared to be substantially higher than for isolated mitochondria. Creatine lowered this Km in trout and turtle, thus indicating a functional coupling between mitochondrial creatine kinase and respiration. However, creatine had no effect on Km in cod ventricle. In conclusion, the creatine kinase-system in trout and turtle hearts seems to fulfil the same functions as in the mammalian heart, i.e. facilitating energy transport and communication between cellular compartments. In cod heart, however, this does not seem to be the case. PMID:12856133

  5. Role of creatine supplementation in exercise-induced muscle damage: A mini review

    PubMed Central

    Kim, Jooyoung; Lee, Joohyung; Kim, Seungho; Yoon, Daeyoung; Kim, Jieun; Sung, Dong Jun

    2015-01-01

    Muscle damage is induced by both high-intensity resistance and endurance exercise. Creatine is a widely used dietary supplement to improve exercise performance by reducing exercise-induced muscle damage. Many researchers have suggested that taking creatine reduces muscle damage by decreasing the inflammatory response and oxidative stress, regulating calcium homeostasis, and activating satellite cells. However, the underlying mechanisms of creatine and muscle damage have not been clarified. Therefore, this review discusses the regulatory effects of creatine on muscle damage by compiling the information collected from basic science and sports science research. PMID:26535213

  6. Maternal creatine supplementation affects the morpho-functional development of hippocampal neurons in rat offspring.

    PubMed

    Sartini, S; Lattanzi, D; Ambrogini, P; Di Palma, M; Galati, C; Savelli, D; Polidori, E; Calcabrini, C; Rocchi, M B L; Sestili, P; Cuppini, R

    2016-01-15

    Creatine supplementation has been shown to protect neurons from oxidative damage due to its antioxidant and ergogenic functions. These features have led to the hypothesis of creatine supplementation use during pregnancy as prophylactic treatment to prevent CNS damage, such as hypoxic-ischemic encephalopathy. Unfortunately, very little is known on the effects of creatine supplementation during neuron differentiation, while in vitro studies revealed an influence on neuron excitability, leaving the possibility of creatine supplementation during the CNS development an open question. Using a multiple approach, we studied the hippocampal neuron morphological and functional development in neonatal rats born by dams supplemented with 1% creatine in drinking water during pregnancy. CA1 pyramidal neurons of supplemented newborn rats showed enhanced dendritic tree development, increased LTP maintenance, larger evoked-synaptic responses, and higher intrinsic excitability in comparison to controls. Moreover, a faster repolarizing phase of action potential with the appearance of a hyperpolarization were recorded in neurons of the creatine-treated group. Consistently, CA1 neurons of creatine exposed pups exhibited a higher maximum firing frequency than controls. In summary, we found that creatine supplementation during pregnancy positively affects morphological and electrophysiological development of CA1 neurons in offspring rats, increasing neuronal excitability. Altogether, these findings emphasize the need to evaluate the benefits and the safety of maternal intake of creatine in humans. PMID:26592720

  7. Effects of creatine supplementation on oxidative stress profile of athletes

    PubMed Central

    2012-01-01

    Background Creatine (Cr) supplementation has been widely used among athletes and physically active individuals. Secondary to its performance-enhancing ability, an increase in oxidative stress may occur, thus prompting concern about its use. The purpose of this study is to investigate the effects of Cr monohydrate supplementation and resistance training on muscle strength and oxidative stress profile in healthy athletes. Methods A randomized, double-blind, placebo-controlled method was used to assess twenty-six male elite Brazilian handball players divided into 3 groups: Cr monohydrate supplemented group (GC, N = 9), placebo group (GP, N = 9), no treatment group (COT, N = 8) for 32 days. All subjects underwent a resistance training program. Blood samples were drawn on 0 and 32 days post Cr supplementation to analyze the oxidative stress markers, thiobarbituric acid reactive species (TBARS), total antioxidant status (TAS), and uric acid. Creatine phosphokinase, urea, and creatinine were also analyzed, as well. Fitness tests (1 repetition maximum - 1RM and muscle endurance) were performed on the bench press. Body weight and height, body fat percentage (by measuring skin folds) and upper muscular area were also evaluated. Statistical analysis was performed using ANOVA. Results Only GC group showed increase in 1RM (54 ± 9 vs. 63 ± 10 kg; p = 0.0356) and uric acid (4.6 ± 1.0 vs. 7.4 ± 1.6 mg/dl; p = 0.025), with a decrease in TAS (1.11 ± 0.34 vs. 0.60 ± 0.19 mmol/l; p = 0.001). No differences (pre- vs. post-training) in TBARS, creatine phosphokinase, urea, creatinine, body weight and height, body fat percentage, or upper muscular area were observed in any group. When compared to COT, GC group showed greater decrease in TAS (−0.51 ± 0.36 vs. -0.02 ± 0.50 mmol/l; p = 0.0268), higher increase in 1RM (8.30 ± 2.26 vs. 5.29 ± 2.36 kg; p = 0.0209) and uric acid (2.77 ± 1.70 vs. 1.00 ± 1.03 mg/dl; p = 0.0276). Conclusion We conclude that Cr monohydrate supplementation associated with a specific resistance program promoted a meaningful increase in muscle strength without inducing changes in body composition. The observed significant increase in uric acid and the decrease in TAS suggest that creatine supplementation, despite promoting acute effects on muscle strength improvement, might induce oxidative stress and decreases total antioxidant status of subjects. PMID:23259853

  8. Non-invasive Monitoring of Lactate Dynamics in Human Forearm Muscle After Exhaustive Exercise by 1H-MRS at 7T

    PubMed Central

    Ren, Jimin; Sherry, A. Dean; Malloy, Craig R.

    2013-01-01

    Despite its importance in energy metabolism, lactate in human skeletal muscle has been difficult to detect by non-invasive 1H MRS mainly due to interference from large water and lipid signals. Long echo-time (TE) acquisitions at 7 Tesla effectively attenuates the water and lipid signals in forearm muscle allowing direct observation of both lactate resonances, the methine at 4.09 ppm and the methyl at 1.31 ppm. Using this approach, we are able to monitor lactate dynamics at a temporal resolution of 32 sec. While lactate was not detectable at rest, immediately after an acute period of exercise to fatigue the forearm muscle, lactate rose to a level comparable to that of creatine (~30 mmol/kg wet weight). In a typical 1H MR spectrum collected using a TE of 140 ms, the lactate methine and methyl resonances both appear as doublets with an unusually large splitting of ~20 Hz due to residual dipolar coupling. During muscle recovery following exercise, the lactate signals decay rapidly with a time constant of t½ = 2.0 ± 0.6 min (n = 12 subjects). This fast and simple lactate detection method may prove valuable for monitoring lactate metabolism in cancer and in sports medicine applications. PMID:23192863

  9. Screening for X-linked creatine transporter (SLC6A8) deficiency via simultaneous determination of urinary creatine to creatinine ratio by tandem mass-spectrometry.

    PubMed

    Mercimek-Mahmutoglu, Saadet; Muehl, Adolf; Salomons, Gajja S; Neophytou, Birgit; Moeslinger, Dorothea; Struys, Eduard; Bodamer, Olaf A; Jakobs, Cornelis; Stockler-Ipsiroglu, Sylvia

    2009-04-01

    High urinary creatine to creatinine ratio (U-CrCrtR) is a potential diagnostic marker of X-linked creatine transporter (SLC6A8) deficiency. We developed a tandem mass-spectrometry method to simultaneously determine urinary creatine and creatinine in 975 individuals (0-18 years). U-CrCrtR increased up to 8 years and decreased thereafter. U-CrCrtR was 2.29 and 2.12 (99th percentile: 1.87) in two males with subsequently confirmed SLC6A8 mutations. The frequency of SLC6A8 deficiency was 2.3% in 157 males at risk. PMID:19188083

  10. Uranyl nitrate inhibits lactate gluconeogenesis in isolated human and mouse renal proximal tubules: A {sup 13}C-NMR study

    SciTech Connect

    Renault, Sophie; Faiz, Hassan; Gadet, Rudy; Ferrier, Bernard; Martin, Guy; Baverel, Gabriel; Conjard-Duplany, Agnes

    2010-01-01

    As part of a study on uranium nephrotoxicity, we investigated the effect of uranyl nitrate in isolated human and mouse kidney cortex tubules metabolizing the physiological substrate lactate. In the millimolar range, uranyl nitrate reduced lactate removal and gluconeogenesis and the cellular ATP level in a dose-dependent fashion. After incubation in phosphate-free Krebs-Henseleit medium with 5 mM L-[1-{sup 13}C]-, or L-[2-{sup 13}C]-, or L-[3-{sup 13}C]lactate, substrate utilization and product formation were measured by enzymatic and NMR spectroscopic methods. In the presence of 3 mM uranyl nitrate, glucose production and the intracellular ATP content were significantly reduced in both human and mouse tubules. Combination of enzymatic and NMR measurements with a mathematical model of lactate metabolism revealed an inhibition of fluxes through lactate dehydrogenase and the gluconeogenic enzymes in the presence of 3 mM uranyl nitrate; in human and mouse tubules, fluxes were lowered by 20% and 14% (lactate dehydrogenase), 27% and 32% (pyruvate carboxylase), 35% and 36% (phosphoenolpyruvate carboxykinase), and 39% and 45% (glucose-6-phosphatase), respectively. These results indicate that natural uranium is an inhibitor of renal lactate gluconeogenesis in both humans and mice.

  11. Guanidinoacetate Is More Effective than Creatine at Enhancing Tissue Creatine Stores while Consequently Limiting Methionine Availability in Yucatan Miniature Pigs

    PubMed Central

    McBreairty, Laura E.; Robinson, Jason L.; Furlong, Kayla R.; Brunton, Janet A.; Bertolo, Robert F.

    2015-01-01

    Creatine (Cr) is an important high-energy phosphate buffer in tissues with a high energy demand such as muscle and brain and is consequently a highly consumed nutritional supplement. Creatine is synthesized via the S-adenosylmethionine (SAM) dependent methylation of guanidinoacetate (GAA) which is not regulated by a feedback mechanism. The first objective of this study was to determine the effectiveness of GAA at increasing tissue Cr stores. Because SAM is required for other methylation reactions, we also wanted to determine whether an increased creatine synthesis would lead to a lower availability of methyl groups for other methylated products. Three month-old pigs (n = 18) were fed control, GAA- or Cr-supplemented diets twice daily. On day 18 or 19, anesthesia was induced 1–3 hours post feeding and a bolus of [methyl-3H]methionine was intravenously infused. After 30 minutes, the liver was analyzed for methyl-3H incorporation into protein, Cr, phosphatidylcholine (PC) and DNA. Although both Cr and GAA led to higher hepatic Cr concentration, only supplementation with GAA led to higher levels of muscle Cr (P < 0.05). Only GAA supplementation resulted in lower methyl-3H incorporation into PC and protein as well as lower hepatic SAM concentration compared to the controls, suggesting that Cr synthesis resulted in a limited methyl supply for PC and protein synthesis (P < 0.05). Although GAA is more effective than Cr at supporting muscle Cr accretion, further research should be conducted into the long term consequences of a limited methyl supply and its effects on protein and PC homeostasis. PMID:26110793

  12. Guanidinoacetate is more effective than creatine at enhancing tissue creatine stores while consequently limiting methionine availability in Yucatan miniature pigs.

    PubMed

    McBreairty, Laura E; Robinson, Jason L; Furlong, Kayla R; Brunton, Janet A; Bertolo, Robert F

    2015-01-01

    Creatine (Cr) is an important high-energy phosphate buffer in tissues with a high energy demand such as muscle and brain and is consequently a highly consumed nutritional supplement. Creatine is synthesized via the S-adenosylmethionine (SAM) dependent methylation of guanidinoacetate (GAA) which is not regulated by a feedback mechanism. The first objective of this study was to determine the effectiveness of GAA at increasing tissue Cr stores. Because SAM is required for other methylation reactions, we also wanted to determine whether an increased creatine synthesis would lead to a lower availability of methyl groups for other methylated products. Three month-old pigs (n = 18) were fed control, GAA- or Cr-supplemented diets twice daily. On day 18 or 19, anesthesia was induced 1-3 hours post feeding and a bolus of [methyl-3H]methionine was intravenously infused. After 30 minutes, the liver was analyzed for methyl-3H incorporation into protein, Cr, phosphatidylcholine (PC) and DNA. Although both Cr and GAA led to higher hepatic Cr concentration, only supplementation with GAA led to higher levels of muscle Cr (P < 0.05). Only GAA supplementation resulted in lower methyl-3H incorporation into PC and protein as well as lower hepatic SAM concentration compared to the controls, suggesting that Cr synthesis resulted in a limited methyl supply for PC and protein synthesis (P < 0.05). Although GAA is more effective than Cr at supporting muscle Cr accretion, further research should be conducted into the long term consequences of a limited methyl supply and its effects on protein and PC homeostasis. PMID:26110793

  13. A novel mouse model of creatine transporter deficiency

    PubMed Central

    Baroncelli, Laura; Alessandrì, Maria Grazia; Tola, Jonida; Putignano, Elena; Migliore, Martina; Amendola, Elena; Gross, Cornelius; Leuzzi, Vincenzo; Cioni, Giovanni; Pizzorusso, Tommaso

    2014-01-01

    Mutations in the creatine (Cr) transporter (CrT) gene lead to cerebral creatine deficiency syndrome-1 (CCDS1), an X-linked metabolic disorder characterized by cerebral Cr deficiency causing intellectual disability, seizures, movement  and behavioral disturbances, language and speech impairment ( OMIM #300352). CCDS1 is still an untreatable pathology that can be very invalidating for patients and caregivers. Only two murine models of CCDS1, one of which is an ubiquitous knockout mouse, are currently available to study the possible mechanisms underlying the pathologic phenotype of CCDS1 and to develop therapeutic strategies. Given the importance of validating phenotypes and efficacy of promising treatments in more than one mouse model we have generated a new murine model of CCDS1 obtained by ubiquitous deletion of 5-7 exons in the Slc6a8 gene. We showed a remarkable Cr depletion in the murine brain tissues and cognitive defects, thus resembling the key features of human CCDS1. These results confirm that CCDS1 can be well modeled in mice. This CrT −/y murine model will provide a new tool for increasing the relevance of preclinical studies to the human disease. PMID:25485098

  14. The therapeutic role of creatine in Huntington's disease.

    PubMed

    Ryu, Hoon; Rosas, H Diana; Hersch, Steven M; Ferrante, Robert J

    2005-11-01

    Huntington's disease (HD) is an autosomal dominant and fatal neurological disorder characterized by a clinical triad of progressive choreiform movements, psychiatric symptoms, and cognitive decline. HD is caused by an expanded trinucleotide CAG repeat in the gene coding for the protein huntingtin. No proven treatment to prevent the onset or to delay the progression of HD currently exists. While a direct causative pathway from the gene mutation to the selective neostriatal neurodegeneration remains unclear, it has been hypothesized that interactions of the mutant huntingtin protein or its fragments may result in a number of interrelated pathogenic mechanisms triggering a cascade of molecular events that lead to the untimely neuronal death observed in HD. One putative pathological mechanism reported to play a prominent role in the pathogenesis of HD is mitochondrial dysfunction and the subsequent reduction of cellular energy. Indeed, if mitochondrial impairment and reduced energy stores play roles in the neuronal loss in HD, then a therapeutic strategy that buffers intracellular energy levels may ameliorate the neurodegenerative process. Sustained ATP levels may have both direct and indirect importance in ameliorating the severity of many of the pathogenic mechanisms associated with HD. Creatine, a guanidino compound produced endogenously and acquired exogenously through diet, is a critical component in maintaining much needed cellular energy. As such, creatine is one of a number of ergogens that may provide a relatively safe and immediately available therapeutic strategy to HD patients that may be the cornerstone of a combined treatment necessary to delay the relentless progression of HD. PMID:16055197

  15. Lactate Regulates Rat Male Germ Cell Function through Reactive Oxygen Species

    PubMed Central

    Galardo, María Noel; Regueira, Mariana; Riera, María Fernanda; Pellizzari, Eliana Herminia; Cigorraga, Selva Beatriz; Meroni, Silvina Beatriz

    2014-01-01

    Besides giving structural support, Sertoli cells regulate the fate of germ cells by supplying a variety of factors. These factors include hormones, several pro- and anti-apoptotic agents and also energetic substrates. Lactate is one of the compounds produced by Sertoli cells, which is utilized as an energetic substrate by germ cells, particularly spermatocytes and spermatids. Beyond its function as an energy source, some studies have proposed a role of lactate in the regulation of gene expression not strictly related to the energetic state of the cells. The general hypothesis that motivated this investigation was that lactate affects male germ cell function, far beyond its well-known role as energetic substrate. To evaluate this hypothesis we investigated: 1) if lactate was able to regulate germ cell gene expression and if reactive oxygen species (ROS) participated in this regulation, 2) if different signal transduction pathways were modified by the production of ROS in response to lactate and 3) possible mechanisms that may be involved in lactate stimulation of ROS production. In order to achieve these goals, cultures of germ cells obtained from male 30-day old rats were exposed to 10 or 20 mM lactate. Increases in lactate dehydrogenase (LDH) C and monocarboxylate transporter (MCT)2 expression, in Akt and p38-MAPK phosphorylation levels and in ROS production were observed. These effects were impaired in the presence of a ROS scavenger. Lactate stimulated ROS production was also inhibited by a LDH inhibitor or a NAD(P)H oxidase (NOX) inhibitor. NOX4 expression was identified in male germ cells. The results obtained herein are consistent with a scenario where lactate, taken up by germ cells, becomes oxidized to pyruvate with the resultant increase in NADH, which is a substrate for NOX4. ROS, products of NOX4 activity, may act as second messengers regulating signal transduction pathways and gene expression. PMID:24498241

  16. In Vivo{sup 1}H Magnetic Resonance Spectroscopy of Lactate in Patients With Stage IV Head and Neck Squamous Cell Carcinoma

    SciTech Connect

    Le, Quynh-Thu Koong, Albert; Lieskovsky, Yee Yie; Narasimhan, Balasubramanian; Graves, Edward; Pinto, Harlan; Brown, J. Martin; Spielman, Daniel

    2008-07-15

    Purpose: To investigate in vivo{sup 1}H magnetic resonance spectroscopy imaging of lactate for assessing tumor hypoxia in head and neck cancers and to determine its utility in predicting the response and outcomes. Methods and Materials: Volume-localized lactate-edited {sup 1}H magnetic resonance spectroscopy at 1.5 T was performed in vivo on involved neck nodes and control subcutaneous tissues in 36 patients with Stage IV head and neck cancer. The signal intensities (SIs) of lactate, choline, and creatine and the choline/creatine ratio were measured. The tumor partial pressure of oxygen (pO{sub 2}) was obtained in the same lymph node before MRS. Patients were treated with either two cycles of induction chemotherapy (tirapazamine, cisplatin, 5-fluorouracil) followed by simultaneous chemoradiotherapy or the same regimen without tirapazamine. The lactate SI and the choline/creatine ratio correlated with the tumor pO{sub 2}, nodal response, and locoregional control. Results: The lactate SI was greater for the involved nodes (median, 0.25) than for the subcutaneous tissue (median, 0.04; p = 0.07). No significant correlation was found between the lactate SI and tumor pO{sub 2} (mean, 0.46 {+-} 0.10 for hypoxic nodes [pO{sub 2} {<=}10 mm Hg, n = 15] vs. 0.36 {+-} 0.07 for nonhypoxic nodes [pO{sub 2} >10 mm Hg, n = 21], p = 0.44). A significant correlation was found between the choline/creatine ratios and tumor pO{sub 2} (mean, 2.74 {+-} 0.34 for hypoxic nodes vs. 1.78 {+-} 0.31 for nonhypoxic nodes, p = 0.02). No correlation was found between the lactate SI and the complete nodal response (p = 0.52) or locoregional control rates. Conclusions: The lactate SI did not correlate with tumor pO{sub 2}, treatment response, or locoregional control. Additional research is needed to refine this technique.

  17. Focally Elevated Creatine Detected in Amyloid Precursor Protein (APP) Transgenic Mice and Alzheimer Disease Brain Tissue

    SciTech Connect

    Gallant,M.; Rak, M.; Szeghalmi, A.; Del Bigio, M.; Westaway, D.; Yang, J.; Julian, R.; Gough, K.

    2006-01-01

    The creatine/phosphocreatine system, regulated by creatine kinase, plays an important role in maintaining energy balance in the brain. Energy metabolism and the function of creatine kinase are known to be affected in Alzheimer diseased brain and in cells exposed to the {beta}-amyloid peptide. We used infrared microspectroscopy to examine hippocampal, cortical, and caudal tissue from 21-89-week-old transgenic mice expressing doubly mutant (K670N/M671L and V717F) amyloid precursor protein and displaying robust pathology from an early age. Microcrystalline deposits of creatine, suggestive of perturbed energetic status, were detected by infrared microspectroscopy in all animals with advanced plaque pathology. Relatively large creatine deposits were also found in hippocampal sections from post-mortem Alzheimer diseased human brain, compared with hippocampus from non-demented brain. We therefore speculate that this molecule is a marker of the disease process.

  18. A review of creatine supplementation in age-related diseases: more than a supplement for athletes

    PubMed Central

    Smith, Rachel N.; Agharkar, Amruta S.; Gonzales, Eric B.

    2014-01-01

    Creatine is an endogenous compound synthesized from arginine, glycine and methionine. This dietary supplement can be acquired from food sources such as meat and fish, along with athlete supplement powders. Since the majority of creatine is stored in skeletal muscle, dietary creatine supplementation has traditionally been important for athletes and bodybuilders to increase the power, strength, and mass of the skeletal muscle. However, new uses for creatine have emerged suggesting that it may be important in preventing or delaying the onset of neurodegenerative diseases associated with aging. On average, 30% of muscle mass is lost by age 80, while muscular weakness remains a vital cause for loss of independence in the elderly population. In light of these new roles of creatine, the dietary supplement’s usage has been studied to determine its efficacy in treating congestive heart failure, gyrate atrophy, insulin insensitivity, cancer, and high cholesterol. In relation to the brain, creatine has been shown to have antioxidant properties, reduce mental fatigue, protect the brain from neurotoxicity, and improve facets/components of neurological disorders like depression and bipolar disorder. The combination of these benefits has made creatine a leading candidate in the fight against age-related diseases, such as Parkinson’s disease, Huntington’s disease, amyotrophic lateral sclerosis, long-term memory impairments associated with the progression of Alzheimer’s disease, and stroke. In this review, we explore the normal mechanisms by which creatine is produced and its necessary physiology, while paying special attention to the importance of creatine supplementation in improving diseases and disorders associated with brain aging and outlining the clinical trials involving creatine to treat these diseases. PMID:25664170

  19. Exercise performance and muscle contractile properties after creatine monohydrate supplementation in aerobic-anaerobic training rats.

    PubMed

    Boyadjiev, Nickolay; Popov, Dobrin; Delchev, Slavi

    2007-01-01

    The purpose of this study was to investigate the effects of creatine monohydrate supplementation on exercise performance and contractile variables in aerobic-anaerobic training rats. Twenty 90-day-old male Sprague Dawley rats were divided into two groups - creatine (Cr) and controls (K). The creatine group received creatine monohydrate as a nutritional supplement, whereas the control group was given placebo. Both groups were trained 5 days a week on a treadmill for 20 days in a mixed (aerobic-anaerobic) metabolic working regimen (27 m·min(-1), 15% elevation for 40 min). The exercise performance (sprint-test), contractile properties (m. tibialis anterior), oxidative enzyme activity (SDH, LDH, NADH2) in m. soleus and blood hematological and chemical variables were assessed in the groups at the end of the experiment. It was found out that creatine supplementation improved the exercise performance after 20 days of administration in a dose of 60 mg per day on the background of a mixed (aerobic-anaerobic) exercise training. At the end of the trial the Cr-group demonstrated better values for the variables which characterize the contractile properties of m. tibialis anterior containing predominantly types IIA and IIB muscle fibers. On the other hand, a higher oxidative capacity was found out in m. soleus (type I muscle fibers) as a result of 20-day creatine supplementation. No side effects of creatine monohydrate supplementation were assessed by the hematological and blood biochemical indices measured in this study. Key pointsThe creatine monohydrate supplementation of the rats diet improves their exercise performance after 20 days administration in a dose of 60 mg per day on the background of a mixed (aerobic-anaerobic) exercise training.The creatine supplemented rats demonstrate better contractile properties of m. tibialis anterior which muscle contains predominantly types IIA and IIB muscle fibers.The soleus muscle (type I muscle fibers) demonstrates a higher oxidative capacity as a result of 20-days creatine supplementation. PMID:24149473

  20. Plasma guanidino compounds are altered by oral creatine supplementation in healthy humans.

    PubMed

    Derave, Wim; Marescau, Bart; Vanden Eede, Els; Eijnde, Bert O; De Deyn, Peter P; Hespel, Peter

    2004-09-01

    Although creatine is one of the most widely used nutritional supplements for athletes as well as for patients with neuromuscular disorders, the effects of oral creatine supplementation on endogenous creatine synthesis in humans remains largely unexplored. The aim of the present study was to investigate the metabolic consequences of a frequently used, long-term creatine ingestion protocol on the circulating creatine synthesis precursor molecules, guanidinoacetate and arginine, and their related guanidino compounds. For this purpose, 16 healthy young volunteers were randomly divided to ingest in a double-blind fashion either creatine monohydrate or placebo (maltodextrine) at a dosage of 20 g/day for the first week (loading phase) and 5 g/day for 19 subsequent wk (maintenance phase). Fasting plasma samples were taken at baseline and at 1, 10, and 20 wk of supplementation, and guanidino compounds were determined. Plasma guanidinoacetate levels were reduced by 50% after creatine loading and remained approximately 30% reduced throughout the maintenance phase. Several circulating guanidino compound levels were significantly altered after creatine loading but not during the maintenance phase: homoarginine (+35%), alpha-keto-delta-guanidinovaleric acid (+45%), and argininic acid (+75%) were increased, whereas guanidinosuccinate was reduced (-25%). The decrease in circulating guanidinoacetate levels suggests that exogenous supply of creatine chronically inhibits endogenous synthesis at the transamidinase step in humans, supporting earlier animal studies showing a powerful repressive effect of creatine on l-arginine:glycine amidinotransferase. Furthermore, these data suggest that this leads to enhanced utilization of arginine as a substrate for secondary pathways. PMID:15107411

  1. A review of creatine supplementation in age-related diseases: more than a supplement for athletes.

    PubMed

    Smith, Rachel N; Agharkar, Amruta S; Gonzales, Eric B

    2014-01-01

    Creatine is an endogenous compound synthesized from arginine, glycine and methionine. This dietary supplement can be acquired from food sources such as meat and fish, along with athlete supplement powders. Since the majority of creatine is stored in skeletal muscle, dietary creatine supplementation has traditionally been important for athletes and bodybuilders to increase the power, strength, and mass of the skeletal muscle. However, new uses for creatine have emerged suggesting that it may be important in preventing or delaying the onset of neurodegenerative diseases associated with aging. On average, 30% of muscle mass is lost by age 80, while muscular weakness remains a vital cause for loss of independence in the elderly population. In light of these new roles of creatine, the dietary supplement's usage has been studied to determine its efficacy in treating congestive heart failure, gyrate atrophy, insulin insensitivity, cancer, and high cholesterol. In relation to the brain, creatine has been shown to have antioxidant properties, reduce mental fatigue, protect the brain from neurotoxicity, and improve facets/components of neurological disorders like depression and bipolar disorder. The combination of these benefits has made creatine a leading candidate in the fight against age-related diseases, such as Parkinson's disease, Huntington's disease, amyotrophic lateral sclerosis, long-term memory impairments associated with the progression of Alzheimer's disease, and stroke. In this review, we explore the normal mechanisms by which creatine is produced and its necessary physiology, while paying special attention to the importance of creatine supplementation in improving diseases and disorders associated with brain aging and outlining the clinical trials involving creatine to treat these diseases. PMID:25664170

  2. Stimulation of creatine kinase BB activity by 1 alpha,25-dihydroxycholecalciferol and 24R,25-dihydroxycholecalciferol in rat tissues.

    PubMed Central

    Smjen, D; Weisman, Y; Binderman, I; Kaye, A M

    1984-01-01

    Vitamin D metabolites stimulate creatine kinase BB activity in organs of vitamin D-deficient rats. In epiphyses of long bones, creatine kinase BB activity increases 2.6-fold 24 h after injection of 24R,25-dihydroxycholecalciferol but not of 1 alpha,25-dihydroxycholecalciferol. Contrariwise, 1 alpha,25-dihydroxycholecalciferol, but not 24R,25-dihydroxycholecalciferol, increases creatine kinase BB activity in diaphyses and in kidney. Neither metabolite affects creatine kinase activity in duodenal mucosa. PMID:6611153

  3. Genomic reconstruction of Shewanella oneidensis MR-1 metabolism reveals previously uncharacterized machinery for lactate utilization

    SciTech Connect

    Pinchuk, Grigoriy E.; Rodionov, Dmitry A.; Yang, Chen; Li, Xiaoqing; Osterman, Andrei L.; Dervyn, Etienne; Geydebrekht, Oleg V.; Reed, Samantha B.; Romine, Margaret F.; Collart, Frank R.; Scott, J.; Fredrickson, Jim K.; Beliaev, Alex S.

    2009-02-24

    The ability to utilize lactate as a sole source of carbon and energy is one of the key metabolic signatures of Shewanellae, a diverse group of dissimilatory metal reducing bacteria commonly found in aquatic and sedimentary environments. Nonetheless, homology searches failed to recognize orthologs of previously described bacterial D- or L-lactate oxidizing enzymes (Escherichia coli genes dld and lldD) in any of the 13 analyzed genomes of Shewanella spp. Using comparative genomic techniques, we identified a conserved chromosomal gene cluster in Shewanella oneidensis MR-1 (locus tag: SO1522-SO1518) containing lactate permease and candidate genes for both D- and L-lactate dehydrogenase enzymes. The predicted D-LDH gene (dldD, SO1521) is a distant homolog of FAD-dependent lactate dehydrogenase from yeast, whereas the predicted L-LDH is encoded by three genes with previously unknown functions (lldEGF, SO1520-19-18). Through a combination of genetic and biochemical techniques, we experimentally confirmed the predicted physiological role of these novel genes in S. oneidensis MR-1 and carried out successful functional validation studies in Escherichia coli and Bacillus subtilis. We conclusively showed that dldD and lldEFG encode fully functional D-and L-LDH enzymes, which catalyze the oxidation of the respective lactate stereoisomers to pyruvate. Notably, the S. oneidensis MR-1 LldEFG enzyme is the first described example of a multi-subunit lactate oxidase. Comparative analysis of >400 bacterial species revealed the presence of LldEFG and Dld in a broad range of diverse species accentuating the potential importance of these previously unknown proteins in microbial metabolism.

  4. Inactivation of creatine kinase induced by quercetin with horseradish peroxidase and hydrogen peroxide. pro-oxidative and anti-oxidative actions of quercetin.

    PubMed

    Miura, T; Muraoka, S; Fujimoto, Y

    2003-06-01

    Pro-oxidative and anti-oxidative actions of quercetin were examined through inactivation of CK and inhibition of lipid peroxidation. Quercetin induced inactivation of creatine kinase (CK) during the interaction with horseradish peroxidase and hydrogen peroxide (HRP-H(2)O(2)). CK activity in heart homogenate was also reduced by quercetin with HRP-H(2)O(2). Flavonoids that have a catechol structure in the B ring, such as taxifolin, catechin and luteolin, also induced CK inactivation. These flavonoids strongly inhibited NADPH and ADP-Fe(3+)-dependent microsomal lipid peroxidation. These results suggest a close relationship between pro-oxidative and anti-oxidative actions of quercetin. Electron spin resonance (ESR) signals of the quercetin radical was emitted during the interaction of quercetin with HRP-H(2)O(2) in the presence of Zn(2+) as a stabilizer. Adding CK diminished the ESR signals of quercetin radicals, suggesting CK efficiently scavenged quercetin radicals. Sulfhydryl groups and tryptophan residues in CK decreased during the interaction of quercetin with HRP-H(2)O(2). The kinetic parameters of K(m) and V(max) for ADP and creatine phosphate changed rapidly, suggesting that the inactivation of CK was induced through conformational change of the enzyme. Glyceraldehyde-3-phosphate dehydrogenase had a higher sensitivity to quercetin with HRP-H(2)O(2) than CK. Quercetin radicals may mediate between pro-oxidative and anti-oxidative action. PMID:12738181

  5. Cerebral energetic effects of creatine supplementation in humans.

    PubMed

    Pan, J W; Takahashi, K

    2007-04-01

    There has been considerable interest in the use of creatine (Cr) supplementation to treat neurological disorders. However, in contrast to muscle physiology, there are relatively few studies of creatine supplementation in the brain. In this report, we use high-field MR (31)P and (1)H spectroscopic imaging of human brain with a 7-day protocol of oral Cr supplementation to examine its effects on cerebral energetics (phosphocreatine, PCr; ATP) and mitochondrial metabolism (N-acetyl aspartate, NAA; and Cr). We find an increased ratio of PCr/ATP (day 0, 0.80 +/- 0.10; day 7, 0.85 +/- 09), with this change largely due to decreased ATP, from 2.7 +/- 0.3 mM to 2.5 +/- 0.3 mM. The ratio of NAA/Cr also decreased (day 0, 1.32 +/- 0.17; day 7 1.18 +/- 0.13), primarily from increased Cr (9.6 +/- 1.9 to 10.1 +/- 2.0 mM). The Cr-induced changes significantly correlated with the basal state, with the fractional increase in PCr/ATP negatively correlating with the basal PCr/ATP value (R = -0.74, P < 0.001). As NAA is a measure of mitochondrial function, there was also a significant negative correlation between basal NAA concentrations with the fractional change in PCr and ATP. Thus healthy human brain energetics is malleable and shifts with 7 days of Cr supplementation, with the regions of initially low PCr showing the largest increments in PCr. Overall, Cr supplementation appears to improve high-energy phosphate turnover in healthy brain and can result in either a decrease or an increase in high-energy phosphate concentrations. PMID:17185404

  6. Clinical use of creatine in neuromuscular and neurometabolic disorders.

    PubMed

    Tarnopolsky, Mark A

    2007-01-01

    Many of the neuromuscular (e.g., muscular dystrophy) and neurometabolic (e.g., mitochondrial cytopathies) disorders share similar final common pathways of cellular dysfunction that may be favorably influenced by creatine monohydrate (CrM) supplementation. Studies using the mdx model of Duchenne muscular dystrophy have found evidence of enhanced mitochondrial function, reduced intra-cellular calcium and improved performance with CrM supplementation. Clinical trials in patients with Duchenne and Becker's muscular dystrophy have shown improved function, fat-free mass, and some evidence of improved bone health with CrM supplementation. In contrast, the improvements in function in myotonic dystrophy and inherited neuropathies (e.g., Charcot-Marie-Tooth) have not been significant. Some studies in patients with mitochondrial cytopathies have shown improved muscle endurance and body composition, yet other studies did not find significant improvements in patients with mitochondrial cytopathy. Lower-dose CrM supplementation in patients with McArdle's disease (myophosphorylase deficiency) improved exercise capacity, yet higher doses actually showed some indication of worsened function. Based upon known cellular pathologies, there are potential benefits from CrM supplementation in patients with steroid myopathy, inflammatory myopathy, myoadenylate deaminase deficiency, and fatty acid oxidation defects. Larger randomized control trials (RCT) using homogeneous patient groups and objective and clinically relevant outcome variables are needed to determine whether creatine supplementation will be of therapeutic benefit to patients with neuromuscular or neurometabolic disorders. Given the relatively low prevalence of some of the neuromuscular and neurometabolic disorders, it will be necessary to use surrogate markers of potential clinical efficacy including markers of oxidative stress, cellular energy charge, and gene expression patterns. PMID:18652078

  7. Migraine in pregnancy and lactation.

    PubMed

    David, Paru S; Kling, Juliana M; Starling, Amaal J

    2014-04-01

    Migraine headache is a significant health problem affecting women more than men. In women, the hormonal fluctuations seen during pregnancy and lactation can affect migraine frequency and magnitude. Understanding the evaluation of headache in pregnancy is important, especially given the increased risk of secondary headache conditions. Pregnancy and lactation can complicate treatment options for women with migraine because of the risk of certain medications to the fetus. This review includes details of the workup and then provides treatment options for migraine during pregnancy and lactation. PMID:24604057

  8. A Pilot Clinical Trial of Creatine and Minocycline in Early Parkinson Disease: 18-Month Results

    PubMed Central

    2015-01-01

    Objective To report an 18-month follow-up on creatine and minocycline futility study, the Neuroprotective Exploratory Trials in Parkinson Disease, Futility Study 1 (NET-PD FS-1). Background The NET-PD FS-1 futility study on creatine and minocycline found neither agent futile in slowing down the progression of disability in Parkinson disease (PD) at 12 months using the prespecified futility threshold. An additional 6 months of follow-up aimed to assess safety and potential interactions of the study interventions with anti-parkinsonian therapy. Methods Additional 6 months of follow-up in randomized, blinded phase II trial of creatine (dosage, 10 g/d) and minocycline (dosage, 200 mg/d) in subjects with early PD. Results By 18 months, symptomatic treatment of PD symptoms was required in 61% of creatine, 62% of minocycline, and 60% of placebo-treated subjects. Study treatment was prematurely discontinued in 9%, 23%, and 6% of subjects in the creatine, minocycline, and placebo arms, respectively. Creatine and minocycline did not seem to adversely influence the response to symptomatic therapy nor increase adverse events. Conclusions Data from this small, 18-month phase II trial of creatine and minocycline do not demonstrate safety concerns that would preclude a large, phase III efficacy trial, although the decreased tolerability of minocycline is a concern. PMID:18520981

  9. Creatine supplementation does not enhance submaximal aerobic training adaptations in healthy young men and women.

    PubMed

    Reardon, T F; Ruell, P A; Fiatarone Singh, M A; Thompson, C H; Rooney, K B

    2006-10-01

    The benefits of dietary creatine supplementation on muscle performance are generally related to an increase in muscle phosphocreatine content. However, creatine supplementation may benefit endurance sports through increased glycogen re-synthesis following exercise. This study investigated the effect of creatine supplementation on muscle glycogen content, submaximal exercise fuel utilisation and endurance performance following 4 weeks of endurance training. Thirteen healthy, physically active, non-vegetarian subjects volunteered to take part and completed the study. Subjects were supplemented with either creatine monohydrate (CREAT, n = 7) or placebo-maltodextrin (CON, n = 6). Submaximal fuel utilisation and endurance performance were assessed before and after a 4 week endurance training program. Muscle biopsies were also collected before and following training for assessment of muscle creatine and glycogen content. Training increased quadriceps glycogen content to the same degree (approximately 20%) in both groups (P = 0.04). There was a significant training effect on submaximal fuel utilisation and improved endurance performance. However, there was no significant treatment effect of creatine supplementation. Creatine supplementation does not effect metabolic adaptations to endurance training. PMID:16896727

  10. The Effects of Creatine Supplementation on Explosive Performance and Optimal Individual Postactivation Potentiation Time

    PubMed Central

    Wang, Chia-Chi; Yang, Ming-Ta; Lu, Kang-Hao; Chan, Kuei-Hui

    2016-01-01

    Creatine plays an important role in muscle energy metabolism. Postactivation potentiation (PAP) is a phenomenon that can acutely increase muscle power, but it is an individualized process that is influenced by muscle fatigue. This study examined the effects of creatine supplementation on explosive performance and the optimal individual PAP time during a set of complex training bouts. Thirty explosive athletes performed tests of back squat for one repetition maximum (1RM) strength and complex training bouts for determining the individual optimal timing of PAP, height and peak power of a counter movement jump before and after the supplementation. Subjects were assigned to a creatine or placebo group and then consumed 20 g of creatine or carboxymethyl cellulose per day for six days. After the supplementation, the 1RM strength in the creatine group significantly increased (p < 0.05). The optimal individual PAP time in the creatine group was also significant earlier than the pre-supplementation and post-supplementation of the placebo group (p < 0.05). There was no significant difference in jump performance between the groups. This study demonstrates that creatine supplementation improves maximal muscle strength and the optimal individual PAP time of complex training but has no effect on explosive performance. PMID:26959056

  11. Creatine Metabolism and Safety Profiles after Six-Week Oral Guanidinoacetic Acid Administration in Healthy Humans

    PubMed Central

    Ostojic, Sergej M.; Niess, Barbara; Stojanovic, Marko; Obrenovic, Milos

    2013-01-01

    Objectives; Guanidinoacetic acid (GAA) is a natural precursor of creatine, yet the potential use of GAA as a nutritional additive for restoring creatine availability in humans has been limited by unclear efficacy and safety after exogenous GAA administration. The present study evaluated the effects of orally administered GAA on serum and urinary GAA, creatine and creatinine concentration, and on the occurrence of adverse events in healthy humans. Methods and Results; Twenty-four healthy volunteers were randomized in a double-blind design to receive either GAA (2.4 grams daily) or placebo (PLA) by oral administration for 6 weeks. Clinical trial registration: www.clinicaltrials.gov, identification number NCT01133899. Serum creatine and creatinine increased significantly from before to after administration in GAA-supplemented participants (P < 0.05). The proportion of participants who reported minor side effects was 58.3% in the GAA group and 45.5% in the placebo group (P = 0.68). A few participants experienced serum creatine levels above 70 µmol/L. Conclusion; Exogenous GAA is metabolized to creatine, resulting in a significant increase of fasting serum creatine after intervention. GAA had an acceptable side-effects profile with a low incidence of biochemical abnormalities. PMID:23329885

  12. The Effects of Creatine Supplementation on Explosive Performance and Optimal Individual Postactivation Potentiation Time.

    PubMed

    Wang, Chia-Chi; Yang, Ming-Ta; Lu, Kang-Hao; Chan, Kuei-Hui

    2016-01-01

    Creatine plays an important role in muscle energy metabolism. Postactivation potentiation (PAP) is a phenomenon that can acutely increase muscle power, but it is an individualized process that is influenced by muscle fatigue. This study examined the effects of creatine supplementation on explosive performance and the optimal individual PAP time during a set of complex training bouts. Thirty explosive athletes performed tests of back squat for one repetition maximum (1RM) strength and complex training bouts for determining the individual optimal timing of PAP, height and peak power of a counter movement jump before and after the supplementation. Subjects were assigned to a creatine or placebo group and then consumed 20 g of creatine or carboxymethyl cellulose per day for six days. After the supplementation, the 1RM strength in the creatine group significantly increased (p < 0.05). The optimal individual PAP time in the creatine group was also significant earlier than the pre-supplementation and post-supplementation of the placebo group (p < 0.05). There was no significant difference in jump performance between the groups. This study demonstrates that creatine supplementation improves maximal muscle strength and the optimal individual PAP time of complex training but has no effect on explosive performance. PMID:26959056

  13. Skeletal muscle properties in a transgenic mouse model for amyotrophic lateral sclerosis: effects of creatine treatment.

    PubMed

    Derave, Wim; Van Den Bosch, Ludo; Lemmens, Griet; Eijnde, Bert O; Robberecht, Wim; Hespel, Peter

    2003-08-01

    The present study was undertaken to identify the metabolic and contractile characteristics of fast- and slow-twitch skeletal muscles in a transgenic mouse model of amyotrophic lateral sclerosis (ALS). In addition, we investigated the effects of oral creatine supplementation on muscle functional capacity in this model. Transgenic mice expressing a mutant (G93A) or wild type human SOD1 gene (WT) were supplemented with 2% creatine monohydrate from 60 to 120 days of age. Body weight, rotorod performance and grip strength were evaluated. In vitro contractility was evaluated on isolated m. soleus and m. extensor digitorum longus (EDL), and muscle metabolites were determined. Body weight, rotorod performance and grip strength were markedly decreased in G93A compared to WT mice, but were unaffected by creatine supplementation. Muscle ATP content decreased and glycogen content increased in G93A versus WT in both muscle types, but were unaffected by creatine supplementation. Muscle creatine content increased following creatine intake in G93A soleus. Twitch and tetanic contractions showed markedly slower contraction and relaxation times in G93A versus WT in both muscle types, with no positive effect of creatine supplementation. EDL but not soleus of G93A mice showed significant atrophy, which was partly abolished by creatine supplementation. It is concluded that overexpression of a mutant SOD1 transgene has profound effects on metabolic and contractile properties of both fast- and slow-twitch skeletal muscles. Furthermore, creatine intake does not exert a beneficial effect on muscle function in a transgenic mouse model of ALS. PMID:12901841

  14. Creatine affords protection against glutamate-induced nitrosative and oxidative stress.

    PubMed

    Cunha, Mauricio P; Lieberknecht, Vicente; Ramos-Hryb, Ana Belén; Olescowicz, Gislaine; Ludka, Fabiana K; Tasca, Carla I; Gabilan, Nelson H; Rodrigues, Ana Lúcia S

    2016-05-01

    Creatine has been reported to exert beneficial effects in several neurodegenerative diseases in which glutamatergic excitotoxicity and oxidative stress play an etiological role. The purpose of this study was to investigate the protective effects of creatine, as compared to the N-Methyl-d-Aspartate (NMDA) receptor antagonist dizocilpine (MK-801), against glutamate or hydrogen peroxide (H2O2)-induced injury in human neuroblastoma SH-SY5Y cells. Exposure of cells to glutamate (60-80 mM) or H2O2 (200-300 μM) for 24 h decreased cellular viability and increased dichlorofluorescein (DCF) fluorescence (indicative of increased reactive oxygen species, ROS) and nitric oxide (NO) production (assessed by mono-nitrogen oxides, NOx, levels). Creatine (1-10 mM) or MK-801 (0.1-10 μM) reduced glutamate- and H2O2-induced toxicity. The protective effect of creatine against glutamate-induced toxicity involves its antioxidant effect, since creatine, similar to MK-801, prevented the increase on DCF fluorescence induced by glutamate or H2O2. Furthermore, creatine or MK-801 blocked glutamate- and H2O2-induced increases in NOx levels. In another set of experiments, the repeated, but not acute, administration of creatine (300 mg/kg, po) in mice prevented the decreases on cellular viability and mitochondrial membrane potential (assessed by tetramethylrhodamine ethyl ester, TMRE, probe) of hippocampal slices incubated with glutamate (10 mM). Creatine concentration-dependent decreased the amount of nitrite formed in the reaction of oxygen with NO produced from sodium nitroprusside solution, suggesting that its protective effect against glutamate or H2O2-induced toxicity might be due to its scavenger activity. Overall, the results suggest that creatine may be useful as adjuvant therapy for neurodegenerative disease treatments. PMID:26804444

  15. Creatine and Its Potential Therapeutic Value for Targeting Cellular Energy Impairment in Neurodegenerative Diseases

    PubMed Central

    Adhihetty, Peter J.

    2010-01-01

    Substantial evidence indicates bioenergetic dysfunction and mitochondrial impairment contribute either directly and/or indirectly to the pathogenesis of numerous neurodegenerative disorders. Treatment paradigms aimed at ameliorating this cellular energy deficit and/or improving mitochondrial function in these neurodegenerative disorders may prove to be useful as a therapeutic intervention. Creatine is a molecule that is produced both endogenously, and acquired exogenously through diet, and is an extremely important molecule that participates in buffering intracellular energy stores. Once creatine is transported into cells, creatine kinase catalyzes the reversible transphosphorylation of creatine via ATP to enhance the phosphocreatine energy pool. Creatine kinase enzymes are located at strategic intracellular sites to couple areas of high energy expenditure to the efficient regeneration of ATP. Thus, the creatinekinase/phosphocreatine system plays an integral role in energy buffering and overall cellular bioenergetics. Originally, exogenous creatine supplementation was widely used only as an ergogenic aid to increase the phosphocreatine pool within muscle to bolster athletic performance. However, the potential therapeutic value of creatine supplementation has recently been investigated with respect to various neurodegenerative disorders that have been associated with bioenergetic deficits as playing a role in disease etiology and/or progression which include; Alzheimer’s, Parkinson’s, amyotrophic lateral sclerosis (ALS), and Huntington’s disease. This review discusses the contribution of mitochondria and bioenergetics to the progression of these neurodegenerative diseases and investigates the potential neuroprotective value of creatine supplementation in each of these neurological diseases. In summary, current literature suggests that exogenous creatine supplementation is most efficacious as a treatment paradigm in Huntington’s and Parkinson’s disease but appears to be less effective for ALS and Alzheimer’s disease. PMID:19005780

  16. Total body skeletal muscle mass: estimation by creatine (methyl-d3) dilution in humans

    PubMed Central

    Walker, Ann C.; O'Connor-Semmes, Robin L.; Leonard, Michael S.; Miller, Ram R.; Stimpson, Stephen A.; Turner, Scott M.; Ravussin, Eric; Cefalu, William T.; Hellerstein, Marc K.; Evans, William J.

    2014-01-01

    Current methods for clinical estimation of total body skeletal muscle mass have significant limitations. We tested the hypothesis that creatine (methyl-d3) dilution (D3-creatine) measured by enrichment of urine D3-creatinine reveals total body creatine pool size, providing an accurate estimate of total body skeletal muscle mass. Healthy subjects with different muscle masses [n = 35: 20 men (19–30 yr, 70–84 yr), 15 postmenopausal women (51–62 yr, 70–84 yr)] were housed for 5 days. Optimal tracer dose was explored with single oral doses of 30, 60, or 100 mg D3-creatine given on day 1. Serial plasma samples were collected for D3-creatine pharmacokinetics. All urine was collected through day 5. Creatine and creatinine (deuterated and unlabeled) were measured by liquid chromatography mass spectrometry. Total body creatine pool size and muscle mass were calculated from D3-creatinine enrichment in urine. Muscle mass was also measured by magnetic resonance imaging (MRI), dual-energy x-ray absorptiometry (DXA), and traditional 24-h urine creatinine. D3-creatine was rapidly absorbed and cleared with variable urinary excretion. Isotopic steady-state of D3-creatinine enrichment in the urine was achieved by 30.7 ± 11.2 h. Mean steady-state enrichment in urine provided muscle mass estimates that correlated well with MRI estimates for all subjects (r = 0.868, P < 0.0001), with less bias compared with lean body mass assessment by DXA, which overestimated muscle mass compared with MRI. The dilution of an oral D3-creatine dose determined by urine D3-creatinine enrichment provides an estimate of total body muscle mass strongly correlated with estimates from serial MRI with less bias than total lean body mass assessment by DXA. PMID:24764133

  17. Functional surface engineering of quantum dot hydrogels for selective fluorescence imaging of extracellular lactate release.

    PubMed

    Zhang, Xiaomeng; Ding, Shushu; Cao, Sumei; Zhu, Anwei; Shi, Guoyue

    2016-06-15

    Selective and sensitive detection of extracellular lactate is of fundamental significance for studying the metabolic alterations in tumor progression. Here we report the rational design and synthesis of a quantum-dot-hydrogel-based fluorescent probe for biosensing and bioimaging the extracellular lactate. By surface engineering the destabilized quantum dot sol with Nile Blue, the destabilized Nile-Blue-functionalized quantum dot sol cannot only self-assemble forming quantum dot hydrogel but also monitor lactate in the presence of nicotinamide adenine dinucleotide cofactor and lactate dehydrogenase through fluorescence resonance energy transfer. Notably, the surface engineered quantum dot hydrogel show high selectivity toward lactate over common metal ions, amino acids and other small molecules that widely coexist in biological system. Moreover, the destabilized Nile-Blue-functionalized quantum dots can encapsulate isolated cancer cells when self-assembled into a hydrogel and thus specifically detect and image the extracellular lactate metabolism. By virtue of these properties, the functionalized quantum dot hydrogel was further successfully applied to monitor the effect of metabolic agents. PMID:26852200

  18. Genetics Home Reference: dihydropyrimidine dehydrogenase deficiency

    MedlinePlus

    ... mutations in the dihydropyrimidine dehydrogenase gene interpreted by analysis of the three-dimensional protein structure. Biochem J. ... R, Nicolai J, Ylstra B, Rubio-Gozalbo ME. Analysis of severely affected patients with dihydropyrimidine dehydrogenase deficiency ...

  19. Genetics Home Reference: succinic semialdehyde dehydrogenase deficiency

    MedlinePlus

    ... People with this condition can also have problems controlling eye movements. Less common features of succinic semialdehyde ... or management of succinic semialdehyde dehydrogenase deficiency: Gene Review: Gene Review: Succinic Semialdehyde Dehydrogenase Deficiency Genetic Testing ...

  20. Fermentation and alternative respiration compensate for NADH dehydrogenase deficiency in a prokaryotic model of DJ-1-associated Parkinsonism.

    PubMed

    Messaoudi, Nadia; Gautier, Valérie; Dairou, Julien; Mihoub, Mouhad; Lelandais, Gaëlle; Bouloc, Philippe; Landoulsi, Ahmed; Richarme, Gilbert

    2015-11-01

    YajL is the closest prokaryotic homologue of Parkinson's disease-associated DJ-1, a protein of undefined function involved in the oxidative stress response. We reported recently that YajL and DJ-1 protect cells against oxidative stress-induced protein aggregation by acting as covalent chaperones for the thiol proteome, including the NuoG subunit of NADH dehydrogenase 1, and that NADH dehydrogenase 1 activity is negligible in the yajL mutant. We report here that this mutant compensates for low NADH dehydrogenase activity by utilizing NADH-independent alternative dehydrogenases, including pyruvate oxidase PoxB and d-amino acid dehydrogenase DadA, and mixed acid aerobic fermentations characterized by acetate, lactate, succinate and ethanol excretion. The yajL mutant has a low adenylate energy charge favouring glycolytic flux, and a high NADH/NAD ratio favouring fermentations over pyruvate dehydrogenase and the Krebs cycle. DNA array analysis showed upregulation of genes involved in glycolytic and pentose phosphate pathways and alternative respiratory pathways. Moreover, the yajL mutant preferentially catabolized pyruvate-forming amino acids over Krebs cycle-related amino acids, and thus the yajL mutant utilizes pyruvate-centred respiro-fermentative metabolism to compensate for the NADH dehydrogenase 1 defect and constitutes an interesting model for studying eukaryotic respiratory complex I deficiencies, especially those associated with Alzheimer's and Parkinson's diseases. PMID:26377309

  1. Effects of Coffee and Caffeine Anhydrous Intake During Creatine Loading.

    PubMed

    Trexler, Eric T; Smith-Ryan, Abbie E; Roelofs, Erica J; Hirsch, Katie R; Persky, Adam M; Mock, Meredith G

    2016-05-01

    Trexler, ET, Smith-Ryan, AE, Roelofs, EJ, Hirsch, KR, Persky, AM, and Mock, MG. Effects of coffee and caffeine anhydrous intake during creatine loading. J Strength Cond Res 30(5): 1438-1446, 2016-The purpose of this study was to determine the effect of 5 days of creatine (CRE) loading alone or in combination with caffeine anhydrous (CAF) or coffee (COF) on upper-body and lower-body strength and sprint performance. Physically active males (n = 54; mean ± SD; age = 20.1 ± 2.1 years; weight = 78.8 ± 8.8 kg) completed baseline testing, consisting of 1 repetition maximum (1RM) and repetitions to fatigue with 80% 1RM for bench press and leg press, followed by a repeated sprint test of five, 10-second sprints separated by 60-second rest on a cycle ergometer to determine peak power (PP) and total power (TP). At least 72 hours later, subjects were randomly assigned to supplement with CRE (5 g of CRE monohydrate, 4 times per day; n = 14), CRE + CAF (CRE +300 mg·d of CAF; n = 13), CRE + COF (CRE +8.9 g of COF, yielding 303 mg of CAF; n = 13), or placebo (PLA; n = 14) for 5 days. Serum creatinine (CRN) was measured before and after supplementation, and on day 6, participants repeated pretesting procedures. Strength measures were improved in all groups (p ≤ 0.05), with no significant time × treatment interactions. No significant interaction or main effects were observed for PP. For TP, a time × sprint interaction was observed (p ≤ 0.05), with no significant interactions among treatment groups. A time × treatment interaction was observed for serum CRN values (p ≤ 0.05) that showed increases in all groups except PLA. Four subjects reported mild gastrointestinal discomfort with CRE + CAF, with no side effects reported in other groups. These findings suggest that neither CRE alone nor in combination with CAF or COF significantly affected performance compared with PLA. PMID:26439785

  2. Effects of N-linked glycosylation on the creatine transporter.

    PubMed

    Straumann, Nadine; Wind, Alexandra; Leuenberger, Tina; Wallimann, Theo

    2006-01-15

    The CRT (creatine transporter) is a member of the Na+- and Cl--dependent neurotransmitter transporter family and is responsible for the import of creatine into cells, and thus is important for cellular energy metabolism. We established for CRT an expression system in HEK-293 cells that allowed biochemical, immunological and functional analysis of CRT wild-type and glycosylation-deficient mutants. Analysis of HA (haemagglutinin)-tagged CRT-NN (wild-type rat CRT with an HA-tag at the C-terminus) revealed several monomeric immunoreactive species with apparent molecular masses of 58, 48 and 43 kDa. The 58 kDa species was shown to be plasma-membrane-resident by EndoHf (endoglycosidase Hf) and PNGase F (peptide N-glycosidase F) treatments and represents fully glycosylated CRT, whereas the 48 kDa and 43 kDa species were glycosylation intermediates and non-glycosylated CRT respectively. Glycosylation-deficient mutants (Asn192Asp, Asn197Asp and Asn192Asp/Asn197Asp) showed altered electrophoretic mobility, indicating that CRT is indeed N-glycosylated. In addition, a prominent CRT band in the range of 75-91 kDa was also detected. Pharmacological inhibition of N-linked glycosylation by tunicamycin in CRT-NN-expressing cells gave a similar reduction in molecular mass, corroborating the finding that Asn192 and Asn197 are major N-glycosylation sites in CRT. Although the apparent Km was not significantly affected in glycosylation-deficient mutants compared with CRT-NN, we measured reduced Vmax values for all mutants (21-28% residual activity), and 51% residual activity after enzymatic deglycosylation of surface proteins in intact CRT-NN cells by PNGase F. Moreover, immunocytochemical analysis of CRT-NN- and CRT-DD-expressing cells (where CRT-DD represents a non-glycosylated double mutant of CRT, i.e. Asn192Asp/Asn197Asp) showed a lower abundance of CRT-DD in the plasma membrane. Taken together, our results suggest that plasma-membrane CRT is glycosylated and has an apparent monomer molecular mass of 58 kDa. Furthermore, N-linked glycosylation is neither exclusively important for the function of CRT nor for surface trafficking, but affects both processes. These findings may have relevance for closely related neurotransmitter transporter family members. PMID:16167890

  3. Creatine supplementation and its effect on musculotendinous stiffness and performance.

    PubMed

    Watsford, Mark L; Murphy, Aron J; Spinks, Warwick L; Walshe, Andrew D

    2003-02-01

    Anecdotal reports suggesting that creatine (Cr) supplementation may cause side effects, such as an increased incidence of muscle strains or tears, require scientific examination. In this study, it was hypothesized that the rapid fluid retention and "dry matter growth" evident after Cr supplementation may cause an increase in musculotendinous stiffness. Intuitively, an increase in musculotendinous stiffness would increase the chance of injury during exercise. Twenty men were randomly allocated to a control or an experimental group and were examined for musculotendinous stiffness of the triceps surae and for numerous performance indices before and after Cr ingestion. The Cr group achieved a significant increase in body mass (79.7 +/- 10.8 kg vs. 80.9 +/- 10.7 kg), counter movement jump height (40.2 +/- 4.8 cm vs. 42.7 +/- 5.9 cm), and 20-cm drop jump height (32.3 +/- 3.3 cm vs. 35.1 +/- 4.8 cm) after supplementation. No increase was found for musculotendinous stiffness at any assessment load. There were no significant changes in any variables within the control group. These findings have both performance- and injury-related implications. Primarily, anecdotal evidence suggesting that Cr supplementation causes muscular strain injuries is not supported by this study. In addition, the increase in jump performance is indicative of performance enhancement in activities requiring maximal power output. PMID:12580652

  4. The genomic organization of a human creatine transporter (CRTR) gene located in Xq28

    SciTech Connect

    Sandoval, N.; Bauer, D.; Brenner, V.

    1996-07-15

    During the course of a large-scale sequencing project in Xq28, a human creatine transporter (CRTR) gene was discovered. The gene is located approximately 36 kb centromeric to ALD. The gene contains 13 exons and spans about 8.5 kb of genomic DNA. Since the creatine transporter has a prominent function in muscular physiology, it is a candidate gene for Barth syndrome and infantile cardiomyopathy mapped to Xq28. 19 refs., 1 fig., 1 tab.

  5. Creatine monohydrate supplementation on lower-limb muscle power in Brazilian elite soccer players

    PubMed Central

    2014-01-01

    Background Studies involving chronic creatine supplementation in elite soccer players are scarce. Therefore, the aim of this study was to examine the effects of creatine monohydrate supplementation on lower-limb muscle power in Brazilian elite soccer players (n = 14 males) during pre-season training. Findings This was a randomized, double-blind, placebo-controlled parallel-group study. Brazilian professional elite soccer players participated in this study. During the pre-season (7 weeks), all the subjects underwent a standardized physical and specific soccer training. Prior to and after either creatine monohydrate or placebo supplementation, the lower-limb muscle power was measured by countermovement jump performance. The Jumping performance was compared between groups at baseline (p = 0.99). After the intervention, jumping performance was lower in the placebo group (percent change = - 0.7%; ES = - 0.3) than in the creatine group (percent change = + 2.4%; ES = + 0.1), but it did not reach statistical significance (p = 0.23 for time x group interaction). Fisher’s exact test revealed that the proportion of subjects that experienced a reduction in jumping performance was significantly greater in the placebo group than in the creatine group (5 and 1, respectively; p = 0.05) after the training. The magnitude-based inferences demonstrated that placebo resulted in a possible negative effect (50%) in jumping performance, whereas creatine supplementation led to a very likely trivial effect (96%) in jumping performance in the creatine group. Conclusions Creatine monohydrate supplementation prevented the decrement in lower-limb muscle power in elite soccer players during a pre-season progressive training. PMID:24991195

  6. Cadmium chloride inhibits lactate gluconeogenesis in isolated human renal proximal tubules: a cellular metabolomic approach with 13C-NMR.

    PubMed

    Faiz, Hassan; Conjard-Duplany, Agnès; Boghossian, Michelle; Martin, Guy; Baverel, Gabriel; Ferrier, Bernard

    2011-09-01

    As part of a study on cadmium nephrotoxicity, we studied the effect of cadmium chloride (CdCl2) in isolated human renal proximal tubules metabolizing the physiological substrate lactate. Dose-effect experiments showed that 10-500 μM CdCl2 reduced lactate removal, glucose production and the cellular levels of ATP, coenzyme A, acetyl-coenzyme A and of reduced glutathione in a dose-dependent manner. After incubation with 5 mM L: -[1-(13)C]-, or L: -[2-(13)C]-, or L: -[3-(13)C] lactate or 5 mM L: -lactate plus 25 mM NaH(13)CO3 as substrates, substrate utilization and product formation were measured by both enzymatic and carbon 13 NMR methods. Combination of enzymatic and NMR measurements with a mathematical model of lactate metabolism previously validated showed that 100 μM CdCl2 caused an inhibition of flux through lactate dehydrogenase and alanine aminotransferase and through the entire gluconeogenic pathway; fluxes were diminished by 19% (lactate dehydrogenase), 28% (alanine aminotransferase), 28% (pyruvate carboxylase), 42% (phosphoenolpyruvate carboxykinase), and 52% (glucose-6-phosphatase). Such effects occurred without altering the oxidation of the lactate carbons or fluxes through enzymes of the tricarboxylic acid cycle despite a large fall of the cellular ATP level, a marker of the energy status and of the viability of the renal cells. These results that were observed at clinically relevant tissue concentrations of cadmium provide a biochemical basis for a better understanding of the cellular mechanism of cadmium-induced renal proximal tubulopathy in humans chronically exposed to cadmium. PMID:21153630

  7. Lactate Utilization Is Regulated by the FadR-Type Regulator LldR in Pseudomonas aeruginosa

    PubMed Central

    Gao, Chao; Hu, Chunhui; Zheng, Zhaojuan; Jiang, Tianyi; Dou, Peipei; Zhang, Wen; Che, Bin; Wang, Yujiao; Lv, Min

    2012-01-01

    NAD-independent l-lactate dehydrogenase (l-iLDH) and NAD-independent d-lactate dehydrogenase (d-iLDH) activities are induced coordinately by either enantiomer of lactate in Pseudomonas strains. Inspection of the genomic sequences of different Pseudomonas strains revealed that the lldPDE operon comprises 3 genes, lldP (encoding a lactate permease), lldD (encoding an l-iLDH), and lldE (encoding a d-iLDH). Cotranscription of lldP, lldD, and lldE in Pseudomonas aeruginosa strain XMG starts with the base, C, that is located 138 bp upstream of the lldP ATG start codon. The lldPDE operon is located adjacent to lldR (encoding an FadR-type regulator, LldR). The gel mobility shift assays revealed that the purified His-tagged LldR binds to the upstream region of lldP. An XMG mutant strain that constitutively expresses d-iLDH and l-iLDH was found to contain a mutation in lldR that leads to an Ile23-to-serine substitution in the LldR protein. The mutated protein, LldRM, lost its DNA-binding activity. A motif with a hyphenated dyad symmetry (TGGTCTTACCA) was identified as essential for the binding of LldR to the upstream region of lldP by using site-directed mutagenesis. l-Lactate and d-lactate interfered with the DNA-binding activity of LldR. Thus, l-iLDH and d-iLDH were expressed when the operon was induced in the presence of l-lactate or d-lactate. PMID:22408166

  8. Towards an effective biosensor for monitoring AD leachate: a knockout E. coli mutant that cannot catabolise lactate.

    PubMed

    Sweeney, Joseph; Murphy, Cormac D; McDonnell, Kevin

    2015-12-01

    Development of a biosensor for the convenient measurement of acetate and propionate concentrations in a two-phase anaerobic digestor (AD) requires a bacterium that will be unresponsive to the other organic acids present in the leachate, of which lactate is the most abundant. Successive gene knockouts of E.coli W3110 D-lactate dehydrogenase (dld), L-lactate dehydrogenase (lldD), glycolate oxidase (glcD) and a suspected L-lactate dehdrogenase (ykgF) were performed. The resulting quadruple mutant (IMD Wldgy) was incapable of growth on D- and L-lactate, whereas the wild type grew readily on these substrates. Furthermore, the O2 consumption rates of acetate-grown IMD Wldgy cell suspensions supplied with either acetate (0.1mM) or a synthetic leachate including acetate (0.1mM) and DL-lactate (1mM) were identical (2.79 and 2.70mgl(-1)min(-1), respectively). This was in marked contrast to similar experiments with the wild type which gave initial O2 consumption rates of 2.00, 2.36 and 2.97mgl(-1)min(-1) when cell suspensions were supplied with acetate (0.1mM), acetate (0.1mM) plus D-lactate (1mM) or acetate (0.1mM) plus L-lactate (1mM), respectively. The knockout strain provides a platform for the design of a biosensor that can accessibly monitor acetate and propionate concentrations in AD leachate via O2-uptake measurements. PMID:26272093

  9. Incorrect calculation of power outputs masks the ergogenic capacity of creatine supplementation.

    PubMed

    Havenetidis, Konstadinos; Cooke, Carlton B; Butterly, Ron; King, Roderick F G J

    2006-10-01

    This study assessed the effect of incorrect calculation of power output measurement on the ergogenic properties of creatine. Fifteen males performed repeated Wingate anaerobic tests, under baseline, placebo, and creatine conditions. Statistics showed significant differences (p < 0.05) following creatine-supplemented conditions compared with placebo conditions, whereas no significant differences existed between the baseline and placebo conditions. However, the performance enhancement effect of creatine became significant only when the corrected (for the inertia of the flywheel) method was employed for measuring peak and minimum power. Mean (+/- SD) values across all cycle sprints for placebo versus creatine were 1033 +/- 100 W versus 1130 +/- 95 W for peak power and 385 +/- 78 W versus 427 +/- 70 W for minimum power. No significant differences were shown using the uncorrected method for peak power (756 +/- 97 W versus 786 +/- 88 W) and minimum power 440 +/- 64 W pre versus 452 +/- 65 W post). In conclusion, the present study suggests that the potentiating effect of creatine might be underestimated if the inertial effects of the flywheel are not considered in power output determination. PMID:17111019

  10. Creatine and Phosphocreatine: A Review of Their Use in Exercise and Sport

    PubMed Central

    Clark, Joseph F.

    1997-01-01

    Objective: Creatine and phosphocreatine (PCr) are important compounds in the normal energy metabolism of muscle. Recently, it has been shown that dietary creatine (5 to 20 g/day) can increase muscle creatine and PCr, with enhancement in anaerobic exercise performance after two weeks of administration caused by an increase in anaerobic capacity. Data Sources: MEDLINE was searched from 1983 to 1996 using key word “creatine” along with “humans,” “muscle,” “exercise,” and “transport.” Also, APStracts, the American Physiology Society search engine for abstracts, was searched from 1994 to 1996. Data Synthesis: Creatine is transported into the muscle cell by a specific transporter, resulting in increased intracellular creatine and PCr. The PCr is capable of acting as an energy buffer, protecting the adenosine triphosphate (ATP) concentration. Maintaining muscle nucleotides therefore enhances exercise performance and recovery. There have been reports that PCr protects the cells from ischemic damage and decreases the loss of nucleotides by stabilizing cell membranes. Indeed, intravenous PCr (2-4 g/day) has been administered to cyclists, resulting in a faster recovery time between training sessions. Conclusions/Recommendations: It is becoming evident that oral creatine supplementation may yield certain benefits to enhance the athlete's performance during maximal anaerobic exercise and interval training. PMID:16558432

  11. Characterization of MB creatine kinase isoform conversion in vitro and in vivo in dogs.

    PubMed Central

    Billadello, J J; Fontanet, H L; Strauss, A W; Abendschein, D R

    1989-01-01

    Time-dependent removal of the COOH-terminal lysine residue from each subunit of tissue MM creatine kinase by plasma carboxypeptidase N produces two additional isoforms that are readily separated, thereby permitting sensitive, early detection of acute myocardial infarction. Only two isoforms of MB creatine kinase have been detected in plasma leading to speculation that the COOH-terminal lysine on the B subunit is resistant to hydrolysis. To define the biochemical changes resulting in MB creatine kinase isoform conversion, we incubated highly purified MB creatine kinase from canine myocardium with plasma carboxypeptidase N. Quantitative anion-exchange chromatography of incubation mixtures and serial plasma samples from dogs subjected to coronary occlusion revealed a second, more acidic form evolved with time that was separated from the tissue isoform. Cyanogen bromide digestion of the two isoforms followed by amino acid sequencing of COOH-terminal peptides showed that MB creatine kinase undergoes removal of the COOH-terminal lysine residue from both M and B subunits. An intermediate form lacking lysine on the M subunit was delineated during incubations by the combined use of anion-exchange chromatography and conventional electrophoretic techniques. Thus, sequential cleavage of lysine from subunits of MB creatine kinase produces an intermediate isoform that has not been detected previously because of difficulties separating it from the tissue and fully converted isoforms. Images PMID:2496146

  12. Nutritional aspects of human lactation*

    PubMed Central

    Thomson, A. M.; Black, A. E.

    1975-01-01

    This paper reviews the literature on the incidence and duration of breast-feeding in various countries, the volume and composition of breast milk, the health and nutrition of breast-fed babies as judged by growth and morbidity, maternal nutritional requirements during lactation, and the effect of prolonged lactation on maternal health. It appears that lactation can be as well sustained by impoverished as by affluent mothers, and that even in communities where malnutrition is common the average growth of infants is satisfactory up to the age of about 3 months on a diet of breast milk alone. Breast milk appears to have specific anti-infective properties, but prolonged breast-feeding will not prevent infections among older infants reared in a poor environment. The authors believe that breast-feeding is the best form of nutrition for the young infant and deplore its decline in modern industrial societies. The recommendations of various FAO/WHO Expert Groups on nutritional intakes during lactation are summarized. The need for an increased daily energy intake of 4.2 MJ (1 000 kcal) is questioned, and an increase of 2.5 MJ (600 kcal) is suggested. Data on the effect of prolonged lactation on the health of the mother are scanty; body weight appears to be maintained even among poorly nourished mothers. The authors stress the need for well-planned and technically adequate studies of the material and psychological factors involved in breast feeding. PMID:816479

  13. Deficiency of dihydrolipoyl dehydrogenase (a component of the pyruvate and alpha-ketoglutarate dehydrogenase complexes): a cause of congenital chronic lactic acidosis in infancy.

    PubMed

    Robinson, B H; Taylor, J; Sherwood, W G

    1977-12-01

    A male child died at 7 months of age with progressive neurologic deterioration and persistent metabolic acidosis. Investigations during life showed this child to have elevated blood pyruvate, lactate, and alpha-ketoglutarate as well as elevation of branched chain amino acids and occasional hypoglycemia. Cofactor therapy using either thiamine-HCl (2 g/kg/24 hr) or thiamine tetrahydrofurfuryl disulfide had no measurable effect on the clinical or biochemical status of the patient. Tissue taken postmortem showed normal levels of key gluconeogenic enzymes but a deficiency in the activity of pyruvate dehydrogenase in all tissues tested (liver, brain, kidney, skeletal muscle, and heart). Examination of the individual activities of pyruvate dehydrogenase complex showed pyruvate decarboxylase (E1) to be normal in liver and other tissues. Dihydrolipoyl dehydrogenase (E3), on the other hand, was deficient in all tissues tested. alpha-Ketoglutarate dehydrogenase complex, which depends of E3 for its total activity, was also deficient in all tissues tested. The absence of this enzyme id discussed in relation to the clinical and biochemical status of the patient. PMID:413089

  14. Antipsychotics in pregnancy and lactation

    PubMed Central

    Babu, Girish N.; Desai, Geetha; Chandra, Prabha S.

    2015-01-01

    Research on psychotropic medications during pregnancy and lactation is limited as often involves complex ethical issues. Information on safety of psychotropic drugs during these critical phases is either inconclusive or undetermined. Many women with severe mental illness have unplanned pregnancies and require antipsychotic medication during pregnancy and lactation. Multiple issues have to be considered while choosing safe treatments for pregnant and lactating women and the best approach is to individualize the treatment. Medication should be guided primarily by its safety data and by the psychiatric history of the patient. Important issues to be kept in mind include pre-pregnancy counseling for all women, including planning pregnancies; folate supplementation, discussion with patient and family regarding options, and active liaison with obstetricians, ultrasonologists and pediatricians. Whenever possible, non-pharmacological approaches should be used in addition. PMID:26330648

  15. Cloning and characterization of the promoter regions from the parent and paralogous creatine transporter genes.

    PubMed

    Ndika, Joseph D T; Lusink, Vera; Beaubrun, Claudine; Kanhai, Warsha; Martinez-Munoz, Cristina; Jakobs, Cornelis; Salomons, Gajja S

    2014-01-10

    Interconversion between phosphocreatine and creatine, catalyzed by creatine kinase is crucial in the supply of ATP to tissues with high energy demand. Creatine's importance has been established by its use as an ergogenic aid in sport, as well as the development of intellectual disability in patients with congenital creatine deficiency. Creatine biosynthesis is complemented by dietary creatine uptake. Intracellular transport of creatine is carried out by a creatine transporter protein (CT1/CRT/CRTR) encoded by the SLC6A8 gene. Most tissues express this gene, with highest levels detected in skeletal muscle and kidney. There are lower levels of the gene detected in colon, brain, heart, testis and prostate. The mechanism(s) by which this regulation occurs is still poorly understood. A duplicated unprocessed pseudogene of SLC6A8-SLC6A10P has been mapped to chromosome 16p11.2 (contains the entire SLC6A8 gene, plus 2293 bp of 5'flanking sequence and its entire 3'UTR). Expression of SLC6A10P has so far only been shown in human testis and brain. It is still unclear as to what is the function of SLC6A10P. In a patient with autism, a chromosomal breakpoint that intersects the 5'flanking region of SLC6A10P was identified; suggesting that SLC6A10P is a non-coding RNA involved in autism. Our aim was to investigate the presence of cis-acting factor(s) that regulate expression of the creatine transporter, as well as to determine if these factors are functionally conserved upstream of the creatine transporter pseudogene. Via gene-specific PCR, cloning and functional luciferase assays we identified a 1104 bp sequence proximal to the mRNA start site of the SLC6A8 gene with promoter activity in five cell types. The corresponding 5'flanking sequence (1050 bp) on the pseudogene also had promoter activity in all 5 cell lines. Surprisingly the pseudogene promoter was stronger than that of its parent gene in 4 of the cell lines tested. To the best of our knowledge, this is the first experimental evidence of a pseudogene with stronger promoter activity than its parental gene. PMID:24144841

  16. Reduction of d-lactate content in sauerkraut using starter cultures of recombinant Leuconostoc mesenteroides expressing the ldhL gene.

    PubMed

    Jin, Qing; Li, Ling; Moon, Jin Seok; Cho, Seung Kee; Kim, Yu Jin; Lee, Soo Jin; Han, Nam Soo

    2016-05-01

    The d-form of lactate, which causes metabolic stress upon excessive dietary intake, is mainly produced by Leuconostoc sp., the predominant species in sauerkraut. To shift the metabolic flux of d-lactate from pyruvate to l-lactate, we expressed the l-lactate dehydrogenase (ldhL) gene in Leuconostoc mesenteroides ATCC 8293. The ldhL gene from Lactobacillus plantarum was introduced into L. mesenteroides using the shuttle vectors pLeuCM and pLeuCM42. To elevate the expression level of ldhL in L. mesenteroides, the nucleotides for pyruvate kinase promoter were fused to ldhL and cloned into above vectors to construct pLC18pkL and pLC42pkL. As results, introduction of pLC42pkL in L. mesenteroides significantly improved both l-LDH activity and l-lactate productivity during fermentation, decreasing the d-/l-lactate ratio. When used as a starter culture for sauerkraut fermentation, recombinant L. mesenteroides harboring pLC42pkL increased l-lactate concentration and decreased d-lactate concentration compared to the wild type strain. We newly developed a recombinant L. mesenteroides which has high l-lactate dehydrogenase activity and applied this strain to minimize the harmful effect of d-lactate during the sauerkraut fermentation. To the best of our knowledge, we demonstrate for the first time the effective use of recombinant Leuconostoc sp. for quality improvement of fermented foods. PMID:26472127

  17. L-lactate utilization by dairy goats

    SciTech Connect

    Rodriguez, N.R.

    1984-01-01

    Three Toggenberg goats were used to investigate utilization of L-lactate as substrate for lipogenesis and gluconeogenesis. Objectives were: (1) to determine the extent lactate could be used for body and milk fat synthesis; (2) to estimate contribution of lactate to glucose synthesis; (3) to assess differences in these measurements during early lactation, mid-lactation and the dry period; and (4) to observe differences in labeling of glycerol and free fatty acid (FFA) fractions in body and milk fat 7 days post-infusion of isotopes. Goats were fed in metabolism crates a 70% concentrate ration in hourly increments to meet individual requirements. After a pulse dose, U-/sup 14/C-lactate (34 uCi/hr) and 6-/sup 3/H-Glucose (100 uCi/hr) was infused via jugular cannula for 8 hours. Blood an milk were sampled hourly beginning 3 and 3.5 hours, respectively, after the pulse dose. Body fat was biopsied after the infusion (Day 0) and one week post-infusion (Day 7). Plasma glucose and lactate concentrations were greater in early 70.4 and 7.7 mg/dl, respectively) compared to mid-lactation (50.8 and 5.9 gm/dl). Mid-lactation and dry period values were similar. Glucose turnover differed for early and mid-lactation and the dry period (141, 86, and 70 mmol/hr, respectively). Percentage of glucose derived from lactate tended to decrease through lactation into the dry period (28% vs 10%). Plasma lactate turnover was greater during lactation as opposed to the dry period (124 and 35 mmol/hr). During early lactation a greater proportion of lactate was incorporated into glucose than during either mid-lactation or the dry period.

  18. The Occurrence of Glycolate Dehydrogenase and Glycolate Oxidase in Green Plants

    PubMed Central

    Frederick, Sue Ellen; Gruber, Peter J.; Tolbert, N. E.

    1973-01-01

    Homogenates of various lower land plants, aquatic angiosperms, and green algae were assayed for glycolate oxidase, a peroxisomal enzyme present in green leaves of higher plants, and for glycolate dehydrogenase, a functionally analogous enzyme characteristic of certain green algae. Green tissues of all lower land plants examined (including mosses, liverworts, ferns, and fern allies), as well as three freshwater aquatic angiosperms, contained an enzyme resembling glycolate oxidase, in that it oxidized l- but not d-lactate in addition to glycolate, and was insensitive to 2 mm cyanide. Many of the green algae (including Chlorella vulgaris, previously claimed to have glycolate oxidase) contained an enzyme resembling glycolate dehydrogenase, in that it oxidized d- but not l-lactate, and was inhibited by 2 mm cyanide. Other green algae had activity characteristic of glycolate oxidase and, accordingly, showed a substantial glycolate-dependent O2 uptake. It is pointed out that this distribution pattern of glycolate oxidase and glycolate dehydrogenase among the green plants may have phylogenetic significance. Activities of catalase, a marker enzyme for peroxisomes, were also determined and were generally lower in the algae than in the land plants or aquatic angiosperms. Among the algae, however, there were no consistent correlations between levels of catalase and the type of enzyme which oxidized glycolate. PMID:16658555

  19. Boosting D-lactate production in engineered cyanobacteria using sterilized anaerobic digestion effluents.

    PubMed

    Hollinshead, Whitney D; Varman, Arul M; You, Le; Hembree, Zachary; Tang, Yinjie J

    2014-10-01

    Anaerobic digestion (AD) is an environmentally friendly approach to waste treatment, which can generate N and P-rich effluents that can be used as nutrient sources for microalgal cultivations. Modifications of AD processes to inhibit methanogenesis leads to the accumulation of acetic acid, a carbon source that can promote microalgal biosynthesis. This study tested different AD effluents from municipal wastes on their effect on D-lactate production by an engineered Synechocystis sp. PCC 6803 (carrying a novel lactate dehydrogenase). The results indicate that: (1) AD effluents can be supplemented into the modified BG-11 culture medium (up to 1:4 volume ratio) to reduce N and P cost; (2) acetate-rich AD effluents enhance D-lactate synthesis by ∼ 40% (1.2g/L of D-lactate in 20 days); and (3) neutral or acidic medium had a deleterious effect on lactate secretion and biomass growth by the engineered strain. This study demonstrates the advantages and guidelines in employing wastewater for photomixotrophic biosynthesis using engineered microalgae. PMID:25084044

  20. Inducing Lactation: Breastfeeding for Adoptive Moms

    MedlinePlus

    ... Español Text Size Email Print Share Inducing Lactation: Breastfeeding for Adoptive Moms Page Content Article Body A growing number of adoptive mothers are interested in breastfeeding their babies through induced lactation. Prescription Medications No ...

  1. Integrated Metabolomics Study of the Milk of Heat-stressed Lactating Dairy Cows.

    PubMed

    Tian, He; Zheng, Nan; Wang, Weiyu; Cheng, Jianbo; Li, Songli; Zhang, Yangdong; Wang, Jiaqi

    2016-01-01

    Heat stress (HS) damages the global dairy industry by reducing milk yields and quality, harming health, and damaging the reproduction of dairy cows, causing huge economic losses each year. However, an understanding of the physiological mechanism of HS lactating dairy cows remains elusive. Here, a metabolomics study using LC-MS and (1)H NMR spectroscopy was performed to analyze the metabolomic differences in the milk between HS-free and HS dairy cows, and discover diagnostic biomarkers and changes in the metabolic pathway. A total of 53 discriminating metabolites were significantly up- or down-regulated in the HS group compared with the HS-free group (P < 0.05). These biomarkers were involved in pathways of carbohydrate, amino acid, lipid, and gut microbiome-derived metabolism. Comparing these potential biomarkers with previously identified HS candidate biomarkers in plasma, significant correlations between the levels of lactate, pyruvate, creatine, acetone, β-hydroxybutyrate, trimethylamine, oleic acid, linoleic acid, lysophosphatidylcholine 16:0, and phosphatidylcholine 42:2 in milk and plasma were found, indicating that the blood-milk barrier became leaky and the levels of these 10 biomarkers in milk can reflect HS-induced metabolomic alterations in blood. These novel findings can support more in-depth research to elucidate the milk-based changes in metabolic pathways in HS lactating dairy cows. PMID:27048914

  2. Integrated Metabolomics Study of the Milk of Heat-stressed Lactating Dairy Cows

    PubMed Central

    Tian, He; Zheng, Nan; Wang, Weiyu; Cheng, Jianbo; Li, Songli; Zhang, Yangdong; Wang, Jiaqi

    2016-01-01

    Heat stress (HS) damages the global dairy industry by reducing milk yields and quality, harming health, and damaging the reproduction of dairy cows, causing huge economic losses each year. However, an understanding of the physiological mechanism of HS lactating dairy cows remains elusive. Here, a metabolomics study using LC-MS and 1H NMR spectroscopy was performed to analyze the metabolomic differences in the milk between HS-free and HS dairy cows, and discover diagnostic biomarkers and changes in the metabolic pathway. A total of 53 discriminating metabolites were significantly up- or down-regulated in the HS group compared with the HS-free group (P < 0.05). These biomarkers were involved in pathways of carbohydrate, amino acid, lipid, and gut microbiome-derived metabolism. Comparing these potential biomarkers with previously identified HS candidate biomarkers in plasma, significant correlations between the levels of lactate, pyruvate, creatine, acetone, β-hydroxybutyrate, trimethylamine, oleic acid, linoleic acid, lysophosphatidylcholine 16:0, and phosphatidylcholine 42:2 in milk and plasma were found, indicating that the blood-milk barrier became leaky and the levels of these 10 biomarkers in milk can reflect HS-induced metabolomic alterations in blood. These novel findings can support more in-depth research to elucidate the milk-based changes in metabolic pathways in HS lactating dairy cows. PMID:27048914

  3. Breast disorders in pregnant and lactating women.

    PubMed

    Faguy, Kathryn

    2015-01-01

    The breast undergoes extensive changes during pregnancy and lactation that can create diagnostic challenges. This article reviews the anatomy of the breast, breast changes associated with pregnancy and lactation, and breast imaging techniques for pregnant and lactating women. Various benign breast conditions in this patient population also are discussed, such as lactating adenomas, galactoceles, and granulomatous mastitis. Finally, pregnancy-associated breast cancer is presented, including its epidemiology, diagnosis, staging, treatment, and prognosis. PMID:25835417

  4. 21 CFR 184.1311 - Ferrous lactate.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... to 155, which is incorporated by reference in accordance with 5 U.S.C. 552(a) and 1 CFR part 51... 21 Food and Drugs 3 2014-04-01 2014-04-01 false Ferrous lactate. 184.1311 Section 184.1311 Food... GRAS § 184.1311 Ferrous lactate. (a) Ferrous lactate (iron (II) lactate, C6H10FeO6, CAS Reg. No....

  5. Imaging Pregnant and Lactating Patients.

    PubMed

    Tirada, Nikki; Dreizin, David; Khati, Nadia J; Akin, Esma A; Zeman, Robert K

    2015-10-01

    As use of imaging in the evaluation of pregnant and lactating patients continues to increase, misperceptions of radiation and safety risks have proliferated, which has led to often unwarranted concerns among patients and clinicians. When radiologic examinations are appropriately used, the benefits derived from the information gained usually outweigh the risks. This review describes appropriateness and safety issues, estimated doses for imaging examinations that use iodizing radiation (ie, radiography, computed tomography, nuclear scintigraphy, and fluoroscopically guided interventional radiology), radiation risks to the mother and conceptus during various stages of pregnancy, and use of iodinated or gadolinium-based contrast agents and radiotracers in pregnant and lactating women. Maternal radiation risk must be weighed with the potential consequences of missing a life-threatening diagnosis such as pulmonary embolus. Fetal risks (ie, spontaneous abortion, teratogenesis, or carcinogenesis) vary with gestational age and imaging modality and should be considered in the context of the potential benefit of medically necessary diagnostic imaging. When feasible and medically indicated, modalities that do not use ionizing radiation (eg, magnetic resonance imaging) are preferred in pregnant and lactating patients. Radiologists should strive to minimize risks of radiation to the mother and fetus, counsel patients effectively, and promote a realistic understanding of risks related to imaging during pregnancy and lactation. PMID:26466183

  6. Diminution of Oxidative Damage to Human Erythrocytes and Lymphocytes by Creatine: Possible Role of Creatine in Blood

    PubMed Central

    Qasim, Neha; Mahmood, Riaz

    2015-01-01

    Creatine (Cr) is naturally produced in the body and stored in muscles where it is involved in energy generation. It is widely used, especially by athletes, as a staple supplement for improving physical performance. Recent reports have shown that Cr displays antioxidant activity which could explain its beneficial cellular effects. We have evaluated the ability of Cr to protect human erythrocytes and lymphocytes against oxidative damage. Erythrocytes were challenged with model oxidants, 2, 2'-azobis(2-amidinopropane) dihydrochloride (AAPH) and hydrogen peroxide (H2O2) in the presence and absence of Cr. Incubation of erythrocytes with oxidant alone increased hemolysis, methemoglobin levels, lipid peroxidation and protein carbonyl content. This was accompanied by decrease in glutathione levels. Antioxidant enzymes and antioxidant power of the cell were compromised while the activity of membrane bound enzyme was lowered. This suggests induction of oxidative stress in erythrocytes by AAPH and H2O2. However, Cr protected the erythrocytes by ameliorating the AAPH and H2O2 induced changes in these parameters. This protective effect was confirmed by electron microscopic analysis which showed that oxidant-induced cell damage was attenuated by Cr. No cellular alterations were induced by Cr alone even at 20 mM, the highest concentration used. Creatinine, a by-product of Cr metabolism, was also shown to exert protective effects, although it was slightly less effective than Cr. Human lymphocytes were similarly treated with H2O2 in absence and presence of different concentrations of Cr. Lymphocytes incubated with oxidant alone had alterations in various biochemical and antioxidant parameters including decrease in cell viability and induction of DNA damage. The presence of Cr attenuated all these H2O2-induced changes in lymphocytes. Thus, Cr can function as a blood antioxidant, protecting cells from oxidative damage, genotoxicity and can potentially increase their lifespan. PMID:26555819

  7. Diminution of Oxidative Damage to Human Erythrocytes and Lymphocytes by Creatine: Possible Role of Creatine in Blood.

    PubMed

    Qasim, Neha; Mahmood, Riaz

    2015-01-01

    Creatine (Cr) is naturally produced in the body and stored in muscles where it is involved in energy generation. It is widely used, especially by athletes, as a staple supplement for improving physical performance. Recent reports have shown that Cr displays antioxidant activity which could explain its beneficial cellular effects. We have evaluated the ability of Cr to protect human erythrocytes and lymphocytes against oxidative damage. Erythrocytes were challenged with model oxidants, 2, 2'-azobis(2-amidinopropane) dihydrochloride (AAPH) and hydrogen peroxide (H2O2) in the presence and absence of Cr. Incubation of erythrocytes with oxidant alone increased hemolysis, methemoglobin levels, lipid peroxidation and protein carbonyl content. This was accompanied by decrease in glutathione levels. Antioxidant enzymes and antioxidant power of the cell were compromised while the activity of membrane bound enzyme was lowered. This suggests induction of oxidative stress in erythrocytes by AAPH and H2O2. However, Cr protected the erythrocytes by ameliorating the AAPH and H2O2 induced changes in these parameters. This protective effect was confirmed by electron microscopic analysis which showed that oxidant-induced cell damage was attenuated by Cr. No cellular alterations were induced by Cr alone even at 20 mM, the highest concentration used. Creatinine, a by-product of Cr metabolism, was also shown to exert protective effects, although it was slightly less effective than Cr. Human lymphocytes were similarly treated with H2O2 in absence and presence of different concentrations of Cr. Lymphocytes incubated with oxidant alone had alterations in various biochemical and antioxidant parameters including decrease in cell viability and induction of DNA damage. The presence of Cr attenuated all these H2O2-induced changes in lymphocytes. Thus, Cr can function as a blood antioxidant, protecting cells from oxidative damage, genotoxicity and can potentially increase their lifespan. PMID:26555819

  8. A novel SLC6A8 mutation associated with motor dysfunction in a child exhibiting creatine transporter deficiency

    PubMed Central

    Cervera-Acedo, Cristina; Lopez, Maria; Aguirre-Lamban, Jana; Santibañez, Paula; Garcia-Oguiza, Alberto; Poch-Olive, Maria Luisa; Dominguez-Garrido, Elena

    2015-01-01

    Creatine transporter (CT) deficiency is an X-linked disorder caused by mutations in the SLC6A8 gene. We describe a clinical, biochemical and molecular examination of a child with X-linked cerebral creatine deficiency. Increased urinary creatine/creatinine ratio, abnormal brain proton magnetic resonance spectroscopy and reduced creatine transport confirmed the clinical diagnosis. SLC6A8 analysis revealed a novel mutation that was hemizygous in the child and not detected in his mother. CT deficiency should be considered in children, especially males, with mental retardation.

  9. 21 CFR 184.1311 - Ferrous lactate.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... sulfate with ammonium lactate. (b) The ingredient meets the specifications of the Food Chemicals Codex...) and 1 CFR part 51. Copies are available from the National Academy Press, 2101 Constitution Ave. NW.... It is prepared by reacting calcium lactate or sodium lactate with ferrous sulfate, direct reaction...

  10. 21 CFR 184.1311 - Ferrous lactate.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    .... (1996), pp. 154 to 155, which is incorporated by reference in accordance with 5 U.S.C. 552(a) and 1 CFR... prepared by reacting calcium lactate or sodium lactate with ferrous sulfate, direct reaction of lactic acid with iron filings, reaction of ferrous chloride with sodium lactate, or reaction of ferrous...

  11. 21 CFR 582.5311 - Ferrous lactate.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 6 2014-04-01 2014-04-01 false Ferrous lactate. 582.5311 Section 582.5311 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Supplements 1 § 582.5311 Ferrous lactate. (a) Product. Ferrous lactate. (b) Conditions of use. This...

  12. 21 CFR 184.1311 - Ferrous lactate.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...) and 1 CFR part 51. Copies are available from the National Academy Press, 2101 Constitution Ave. NW... 21 Food and Drugs 3 2013-04-01 2013-04-01 false Ferrous lactate. 184.1311 Section 184.1311 Food... Specific Substances Affirmed as GRAS § 184.1311 Ferrous lactate. (a) Ferrous lactate (iron (II)...

  13. 21 CFR 184.1639 - Potassium lactate.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 3 2014-04-01 2014-04-01 false Potassium lactate. 184.1639 Section 184.1639 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) DIRECT... GRAS § 184.1639 Potassium lactate. (a) Potassium lactate (C3H5O3K, CAS Reg. No. 996-31-6) is...

  14. 21 CFR 184.1639 - Potassium lactate.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 3 2013-04-01 2013-04-01 false Potassium lactate. 184.1639 Section 184.1639 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR... Specific Substances Affirmed as GRAS § 184.1639 Potassium lactate. (a) Potassium lactate (C3H5O3K, CAS...

  15. 21 CFR 184.1639 - Potassium lactate.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 3 2011-04-01 2011-04-01 false Potassium lactate. 184.1639 Section 184.1639 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR... Specific Substances Affirmed as GRAS § 184.1639 Potassium lactate. (a) Potassium lactate (C3H5O3K, CAS...

  16. 21 CFR 582.5311 - Ferrous lactate.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Ferrous lactate. 582.5311 Section 582.5311 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Supplements 1 § 582.5311 Ferrous lactate. (a) Product. Ferrous lactate. (b) Conditions of use. This...

  17. 21 CFR 582.1207 - Calcium lactate.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Calcium lactate. 582.1207 Section 582.1207 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Additives § 582.1207 Calcium lactate. (a) Product. Calcium lactate. (b) Conditions of use. This substance...

  18. 21 CFR 582.1207 - Calcium lactate.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 6 2014-04-01 2014-04-01 false Calcium lactate. 582.1207 Section 582.1207 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Additives § 582.1207 Calcium lactate. (a) Product. Calcium lactate. (b) Conditions of use. This substance...

  19. 21 CFR 582.1207 - Calcium lactate.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Calcium lactate. 582.1207 Section 582.1207 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Additives § 582.1207 Calcium lactate. (a) Product. Calcium lactate. (b) Conditions of use. This substance...

  20. 21 CFR 184.1768 - Sodium lactate.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 3 2014-04-01 2014-04-01 false Sodium lactate. 184.1768 Section 184.1768 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) DIRECT FOOD....1768 Sodium lactate. (a) Sodium lactate (C3H5O3Na, CAS Reg. No. 72-17-3) is the sodium salt of...

  1. 21 CFR 582.5311 - Ferrous lactate.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Ferrous lactate. 582.5311 Section 582.5311 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Supplements 1 § 582.5311 Ferrous lactate. (a) Product. Ferrous lactate. (b) Conditions of use. This...

  2. 21 CFR 184.1639 - Potassium lactate.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 3 2012-04-01 2012-04-01 false Potassium lactate. 184.1639 Section 184.1639 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR... Specific Substances Affirmed as GRAS § 184.1639 Potassium lactate. (a) Potassium lactate (C3H5O3K, CAS...

  3. 21 CFR 582.5311 - Ferrous lactate.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Ferrous lactate. 582.5311 Section 582.5311 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Supplements 1 § 582.5311 Ferrous lactate. (a) Product. Ferrous lactate. (b) Conditions of use. This...

  4. 21 CFR 582.5311 - Ferrous lactate.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Ferrous lactate. 582.5311 Section 582.5311 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Supplements 1 § 582.5311 Ferrous lactate. (a) Product. Ferrous lactate. (b) Conditions of use. This...

  5. 21 CFR 184.1311 - Ferrous lactate.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...) and 1 CFR part 51. Copies are available from the National Academy Press, 2101 Constitution Ave. NW... 21 Food and Drugs 3 2012-04-01 2012-04-01 false Ferrous lactate. 184.1311 Section 184.1311 Food... Specific Substances Affirmed as GRAS § 184.1311 Ferrous lactate. (a) Ferrous lactate (iron (II)...

  6. The origin and evolution of lactation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The presence of mammary glands are the defining morphological feature of mammals, and a successful lactation is crucial to mammalian reproductive strategies. Among mammalian species, the nature of lactation and the composition of milk vary greatly. The evolution of lactation and its diversity amon...

  7. Inhibition effects of furfural on alcohol dehydrogenase, aldehyde dehydrogenase and pyruvate dehydrogenase.

    PubMed Central

    Modig, Tobias; Lidén, Gunnar; Taherzadeh, Mohammad J

    2002-01-01

    The kinetics of furfural inhibition of the enzymes alcohol dehydrogenase (ADH; EC 1.1.1.1), aldehyde dehydrogenase (AlDH; EC 1.2.1.5) and the pyruvate dehydrogenase (PDH) complex were studied in vitro. At a concentration of less than 2 mM furfural was found to decrease the activity of both PDH and AlDH by more than 90%, whereas the ADH activity decreased by less than 20% at the same concentration. Furfural inhibition of ADH and AlDH activities could be described well by a competitive inhibition model, whereas the inhibition of PDH was best described as non-competitive. The estimated K(m) value of AlDH for furfural was found to be about 5 microM, which was lower than that for acetaldehyde (10 microM). For ADH, however, the estimated K(m) value for furfural (1.2 mM) was higher than that for acetaldehyde (0.4 mM). The inhibition of the three enzymes by 5-hydroxymethylfurfural (HMF) was also measured. The inhibition caused by HMF of ADH was very similar to that caused by furfural. However, HMF did not inhibit either AlDH or PDH as severely as furfural. The inhibition effects on the three enzymes could well explain previously reported in vivo effects caused by furfural and HMF on the overall metabolism of Saccharomyces cerevisiae, suggesting a critical role of these enzymes in the observed inhibition. PMID:11964178

  8. ALTERATIONS IN BRAIN CREATINE CONCENTRATIONS UNDER LONG-TERM SOCIAL ISOLATION (EXPERIMENTAL STUDY).

    PubMed

    Koshoridze, N; Kuchukashvili, Z; Menabde, K; Lekiashvili, Sh; Koshoridze, M

    2016-02-01

    Stress represents one of the main problems of modern humanity. This study was done for understanding more clearly alterations in creatine content of the brain under psycho-emotional stress induced by long-term social isolation. It was shown that under 30 days social isolation creatine amount in the brain was arisen, while decreasing concentrations of synthesizing enzymes (AGAT, GAMT) and creatine transporter protein (CrT). Another important point was that such changes were accompanied by down-regulation of creatine kinase (CK), therefore the enzyme's concentration was lowered. In addition, it was observed that content of phosphocreatine (PCr) and ATP were also reduced, thus indicating down-regulation of energy metabolism of brain that is really a crucial point for its normal functioning. To sum up the results it can be underlined that long-term social isolation has negative influence on energy metabolism of brain; and as a result reduce ATP content, while increase of free creatine concentration, supposedly maintaining maximal balance for ATP amount, but here must be also noted that up-regulated oxidative pathways might have impact on blood brain barrier, resulting on its permeability. PMID:27001789

  9. Effects of oral creatine supplementation on high intensity, intermittent exercise performance in competitive squash players.

    PubMed

    Romer, L M; Barrington, J P; Jeukendrup, A E

    2001-11-01

    The purpose of this study was to determine the effects of oral creatine supplementation on high intensity, intermittent exercise performance in competitive squash players. Nine squash players (mean +/- SEM VO2max = 61.9 +/- 2.1 ml x kg(-1) x min(-1); body mass = 73 +/- 3 kg) performed an on-court "ghosting" routine that involved 10 sets of 2 repetitions of simulated positional play, each set interspersed with 30 s passive recovery. A double blind, crossover design was utilised whereby experimental and control groups supplemented 4 times daily for 5 d with 0.075 g x kg(-1) body mass of creatine monohydrate and maltodextrine, respectively, and a 4 wk washout period separated the crossover of treatments. The experimental group improved mean set sprint time by 3.2 +/- 0.8% over and above the changes noted for the control group (P = 0.004 and 95% Cl = 1.4 to 5.1%). Sets 2 to 10 were completed in a significantly shorter time following creatine supplementation compared to the placebo condition (P < 0.05). In conclusion, these data support existing evidence that creatine supplementation improves high intensity, intermittent exercise performance. In addition, the present study provides new evidence that oral creatine supplementation improves exercise performance in competitive squash players. PMID:11719888

  10. Putative reaction mechanism of heterologously expressed octopine dehydrogenase from the great scallop, Pecten maximus (L).

    PubMed

    Müller, Andre; Janssen, Frank; Grieshaber, Manfred K

    2007-12-01

    cDNA for octopine dehydrogenase (ODH) from the adductor muscle of the great scallop, Pecten maximus, was cloned using 5'- and 3'-RACE. The cDNA comprises an ORF of 1197 nucleotides and the deduced amino acid sequence encodes a protein of 399 amino acids. ODH was heterologously expressed in Escherichia coli with a C-terminal penta His-tag. ODH-5His was purified to homogeneity using metal-chelate affinity chromatography and Sephadex G-100 gel filtration. Recombinant ODH had kinetic properties similar to those of wild-type ODH isolated from the scallop's adductor muscle. Site-directed mutagenesis was used to elucidate the involvement of several amino acid residues for the reaction catalyzed by ODH. Cys148, which is conserved in all opine dehydrogenases known to date, was converted to serine or alanine, showing that this residue is not intrinsically important for catalysis. His212, Arg324 and Asp329, which are also conserved in all known opine dehydrogenase sequences, were subjected to site-directed mutagenesis. Modification of these residues revealed their importance for the catalytic activity of the enzyme. Conversion of each of these residues to alanine resulted in strong increases in K(m) and decreases in k(cat) values for pyruvate and L-arginine, but had little effect on the K(m) and k(cat) values for NADH. Assuming a similar structure for ODH compared with the only available structure of a bacterial opine dehydrogenase, these three amino acids may function as a catalytic triad in ODH similar to that found in lactate dehydrogenase or malate dehydrogenase. The carboxyl group of pyruvate is then stabilized by Arg324. In addition to orienting the substrate, His212 will act as an acid-base catalyst by donating a proton to the carbonyl group of pyruvate. The acidity of this histidine is further increased by the proximity of Asp329. PMID:18028427

  11. Reduction of ferric iron by L-lactate and DL-glycerol-3-phosphate in membrane preparations from Staphylococcus aureus and interactions with the nitrate reductase system.

    PubMed Central

    Lascelles, J; Burke, K A

    1978-01-01

    Membrane fractions with L-lactate dehydrogenase, sn-glycerol-3-phosphate (G3P) dehydrogenase, and nitrate reductase activities were prepared from Staphylococcus aureus wild-type and hem mutant strains. These preparations reduced ferric to ferrous iron with L-lactate or G3P as the source of reductant, using ferrozine to trap the ferrous iron. Reduction of ferric iron was insensitive to 2-heptyl-4-hydroxyquinoline-N-oxide (HQNO) with either L-lactate or G3P as reductant, but oxalate and dicumarol inhibited reduction with L-lactate as substrate. The membranes had L-lactate- and G3P-nitrate reductase activities, which were inhibited by azide and by HQNO. Reduction of ferric iron under anaerobic conditions was inhibited by nitrate with preparations from the wild-type strain. This effect of nitrate was abolished by blocking electron transport to the nitrate reductase system with azide or HQNO. Nitrate did not inhibit reduction of ferric iron in heme-depleted membranes from the hem mutant unless hemin was added to restore L-lactate- and G3P-nitrate reductase activity. We conclude that reduced components of the electron transport chain that precede cytochrome b serve as the source of reductant for ferric iron and that these components are oxidized preferentially by a functional nitrate reductase system. PMID:207671

  12. Haptoglobin therapy for acute favism: a Japanese boy with glucose-6-phosphate dehydrogenase Guadalajara.

    PubMed

    Ohga, S; Higashi, E; Nomura, A; Matsuzaki, A; Hirono, A; Miwa, S; Fujii, H; Ueda, K

    1995-02-01

    We report the case of a 2-year-old Japanese boy with acute favism who was treated with human haptoglobin products. He had been exhibiting chronic nonspherocytic haemolytic anaemia until the diagnosis of glucose-6-phosphate dehydrogenase (G6PD) deficiency when 14 months old. He suffered a favic crisis at 24 months of age, when the administration of haptoglobin was effective for relieving bilirubinaemia and haemoglobinuria. Serum-free Hb rapidly decreased to normal levels despite the sustained level of serum lactate dehydrogenase. His G6PD gene was G6PD Guadalajara. This is the first application of haptoglobin therapy for acute favism and the first reported case of Japanese G6PD deficiency with typical favic crisis. Haptoglobin treatment might be helpful for managing the haemolytic crisis in the disease. PMID:7873396

  13. Pyruvate dehydrogenase deficiency and epilepsy.

    PubMed

    Prasad, Chitra; Rupar, Tony; Prasad, Asuri N

    2011-11-01

    The pyruvate dehydrogenase complex (PDHc) is a mitochondrial matrix multienzyme complex that provides the link between glycolysis and the tricarboxylic acid (TCA) cycle by catalyzing the conversion of pyruvate into acetyl-CoA. PDHc deficiency is one of the commoner metabolic disorders of lactic acidosis presenting with neurological phenotypes that vary with age and gender. In this mini-review, we postulate mechanisms of epilepsy in the setting of PDHc deficiency using two illustrative cases (one with pyruvate dehydrogenase complex E1-alpha polypeptide (PDHA1) deficiency and the second one with pyruvate dehydrogenase complex E1-beta subunit (PDHB) deficiency (a rare subtype of PDHc deficiency)) and a selected review of published case series. PDHc plays a critical role in the pathway of carbohydrate metabolism and energy production. In severe deficiency states the resulting energy deficit impacts on brain development in utero resulting in structural brain anomalies and epilepsy. Milder deficiency states present with variable manifestations that include cognitive delay, ataxia, and seizures. Epileptogenesis in PDHc deficiency is linked to energy failure, development of structural brain anomalies and abnormal neurotransmitter metabolism. The use of the ketogenic diet bypasses the metabolic block, by providing a direct source of acetyl-CoA, leading to amelioration of some symptoms. Genetic counseling is essential as PDHA1 deficiency (commonest defect) is X-linked although females can be affected due to unfavorable lyonization, while PDHB and PDH phosphatase (PDP) deficiencies (much rarer defects) are of autosomal recessive inheritance. Research is in progress for looking into animal models to better understand pathogenesis and management of this challenging disorder. PMID:21908116

  14. Characterization of retinaldehyde dehydrogenase 3

    PubMed Central

    Graham, CarolineE.; Brocklehurst, Keith; Pickersgill, RichardW.; Warren, MartinJ.

    2005-01-01

    RALDH3 (retinal dehydrogenase 3) was characterized by kinetic and binding studies, protein engineering, homology modelling, ligand docking and electrostatic-potential calculations. The major recognition determinant of an RALDH3 substrate was shown to be an eight-carbon chain bonded to the aldehyde group whose kinetic influence (kcat/Km at pH8.5) decreases when shortened or lengthened. Surprisingly, the ?-ionone ring of all-trans-retinal is not a major recognition site. The dissociation constants (Kd) of the complexes of RALDH3 with octanal, NAD+ and NADH were determined by intrinsic tryptophan fluorescence. The similarity of the Kd values for the complexes with NAD+ and with octanal suggests a random kinetic mechanism for RALDH3, in contrast with the ordered sequential mechanism often associated with aldehyde dehydrogenase enzymes. Inhibition of RALDH3 by tri-iodothyronine binding in competition with NAD+, predicted by the modelling, was established kinetically and by immunoprecipitation. Mechanistic implications of the kinetically influential ionizations with macroscopic pKa values of 5.0 and 7.5 revealed by the pH-dependence of kcat are discussed. Analogies with data for non-phosphorylating glyceraldehyde-3-phosphate dehydrogenase from Streptococcus mutans, together with the present modelled structure of the thioacyl RALDH3, suggest (a) that kcat characterizes deacylation of this intermediate for specific substrates and (b) the assignment of the pKa of the major ionization (approximating to 7.5) to the perturbed carboxy group of Glu280 whose conjugate base is envisaged as supplying general base catalysis to attack of a water molecule. The macroscopic pKa of the minor ionization (5.0) is considered to approximate to that of the carboxy group of Glu488. PMID:16241904

  15. Isocitrate dehydrogenase mutations in leukemia

    PubMed Central

    McKenney, Anna Sophia; Levine, Ross L.

    2013-01-01

    Recent genome-wide discovery studies have identified a spectrum of mutations in different malignancies and have led to the elucidation of novel pathways that contribute to oncogenic transformation. The discovery of mutations in the genes encoding isocitrate dehydrogenase (IDH) has uncovered a critical role for altered metabolism in oncogenesis, and the neomorphic, oncogenic function of IDH mutations affects several epigenetic and gene regulatory pathways. Here we discuss the relevance of IDH mutations to leukemia pathogenesis, therapy, and outcome and how mutations in IDH1 and IDH2 affect the leukemia epigenome, hematopoietic differentiation, and clinical outcome. PMID:23999441

  16. Cellobiose dehydrogenase in cellulose degradation

    SciTech Connect

    Eriksson, L.; Igarashi, Kiyohiko; Samejima, Masahiro

    1996-10-01

    Cellobiose dehydrogenase is produced by a variety of fungi. Although it was already discovered during the 70`s, it`s role in cellulose and lignin degradation is yet ambiguous. The enzyme contains both heme and FAD as prosthetic groups, and seems to have a domain specifically designed to bind the enzyme to cellulose. It`s affinity to amorphous cellulose is higher than to crystalline cellulose. We will report on the binding behavior of the enzyme, its usefulness in elucidation of cellulose structures and also, possibilities for applications such as its use in measuring individual and synergistic mechanisms for cellulose degradation by endo- and exo-glucanases.

  17. Creatine kinase: race-gender differences in patients hospitalized for suspected myocardial infarction.

    PubMed Central

    Cook, J. C.; Wong, E.; Haywood, L. J.

    1990-01-01

    Race-gender differences in creatine kinase values were studied in 647 consecutive patients admitted for suspected myocardial infarction. The lowest value in a serial set for each patient was used for group comparisons. Significant differences were found between Hispanic females and black males, using standard values. Using log creatine kinase values, significant differences were found among blacks, Caucasians, and Hispanics. Males had higher log creatine kinase values than females, but no differences were found between sexes within racial groups. Body surface area differences (significant between males and females) did not explain all of the racial-gender differences found. Reexamination of ranges of normality, taking into account race-gender differences, is strongly supported by these data. PMID:2185368

  18. NcoI and TaqI RFLPs for human M creatine kinase (CKM)

    SciTech Connect

    Perryman, M.B.; Hejtmancik, J.F.; Ashizawa, Tetsuo; Armstrong, R.; Lin, Sunchiang; Roberts, R.; Epstein, H.F. )

    1988-09-12

    Probe pHMCKUT contains a 135 bp cDNA fragment inserted into pGEM 3. The probe corresponds to nucleotides 1,201 to 1,336 located in the 3{prime} untranslated region of human M creatine kinase. The probe is specific for human M creatine kinase and does not hybridize to human B cretine kinase sequences. NcoI identifies a two allele polymorphism of a band at either 2.5 kb or 3.6 kb. TaqI identifies a two allele polymorphism at either 3.8 kb or 4.5 kb. Human M creatine has been localized to chromosome 19q. Autosomal co-dominant inheritance was shown in six informative Caucasian families.

  19. The activity of seminal creatine kinase is increased in the presence of pentoxifylline.

    PubMed

    Banihani, S A; Abu-Alhayjaa, R F

    2016-06-01

    Creatine kinase enzyme (CK) is indispensable for sperm function because it catalyses the regeneration of ATP from the chemical shuttle between creatine and creatine phosphate. Here, we measured CK activity of human spermatozoa in the presence of pentoxifylline (PF), a xanthine derivative drug primarily used to treat peripheral vascular function. Nine semen samples from different males were subjected to swim up, incubated with PF and tested for CK activity using the kinetic spectrophotometric method. The CK activity of spermatozoa significantly increased after addition of PF at 5 mm compared with the control (with 0.0 mm PF). Given that PF has been identified as a sperm motility enhancer and that CK is crucial for adequate sperm motion; then, the aptitude of PF to enhance sperm motility may be modulated by increasing CK activity. PMID:26395279

  20. Cerebral proton magnetic resonance spectroscopy demonstrates reversibility of N-acetylaspartate/creatine in gray matter after delayed encephalopathy due to carbon monoxide intoxication: a case report

    PubMed Central

    2014-01-01

    Introduction Predictive markers for long-term outcome in carbon monoxide-intoxicated patients with late encephalopathy are desired. Here we present the first data demonstrating a full reversibility pattern of specific brain substances measured by cerebral proton magnetic resonance spectroscopy in a carbon monoxide-intoxicated victim. This may provide clinicians with important information when estimating patient outcome. Case presentation We report the case of a 40-year-old Caucasian woman with severe carbon monoxide poisoning who was treated with five repetitive sessions of hyperbaric oxygen therapy in a multiplace chamber (100 percent oxygen with a ventilator, 90 minutes exposure to 2.8 atmospheres absolute). Initially, our patient recovered completely after three days of hospitalization, but became encephalopathic after a lucid interval of four weeks. An examination of the brain with cerebral proton magnetic resonance spectroscopy showed a dramatically decrease in N-acetylaspartate to total creatine ratios and elevated lactate levels in the gray matter. Subsequently, our patient received six additional sessions of hyperbaric oxygen therapy with only minimal recovery. At six-month follow-up our patient showed significant improvement in cognition and neuromuscular coordination. Extraordinarily, the cerebral proton magnetic resonance spectroscopy measurements at relapse compared to measurements at follow-up (217 days post insult) revealed full reversal of the severe abnormalities in mid-occipital gray matter and partial reversal in white matter. Conclusions The present case indicates that cerebral proton magnetic spectroscopy provides valuable information on brain metabolism in patients presenting with delayed encephalopathy after acute carbon monoxide intoxication. The full reversal of N-acetylaspartate to total creatine ratios in gray matter has, to our knowledge, never been described before and shows that severe, initial measurements may not predict poor long-term patient outcome. PMID:24947173

  1. Oral supplementations of betaine, choline, creatine and vitamin B6 and their influence on the development of homocysteinaemia in neonatal piglets.

    PubMed

    Côté-Robitaille, Marie-Édith; Girard, Christiane L; Guay, Frédéric; Matte, J Jacques

    2015-01-01

    Homocysteine (Hcy) is an intermediary sulphur amino acid recognised for pro-oxidative properties in several species which may weaken immune competence in piglets. In this species, there is an acute 10-fold increase of concentrations of plasma Hcy (pHcy) during the first 2 weeks of life. The present experiment aimed to determine if pHcy in piglets can be regulated by oral supplementations of betaine as a methyl group supplier, creatine for reducing the demand for methyl groups, choline with both previous functions and vitamin B6 as enzymic co-factor for Hcy catabolism. A total of seventeen sows (second parity) were fed gestation and lactation diets supplemented with folic acid (10 mg/kg) and vitamin B12 (150 µg/kg). Eight piglets in each litter received daily one of the eight following oral treatments (mg/kg body weight): (1) control (saline); (2) betaine (50); (3) choline (70); (4) creatine (300); (5) pyridoxine (0·2); (6) treatments 2 and 5; (7) treatments 3 and 4; and (8) treatments 2, 3, 4 and 5. According to age, pHcy increased sharply from 2·48 µm at birth to 17·96 µm at 21 d of age (P < 0·01). Concentrations of pHcy tended to be lower (P = 0·09) in treated than in control piglets but the highest and sole pairwise significant decrease (23 %) was observed between treatments 1 and 8 (P = 0·03). Growth from birth to 21 d of age was not influenced by treatments (P > 0·70). Therefore, it appears possible to reduce pHcy concentrations in suckling piglets but a combination of all chosen nutrients is required. PMID:26495122

  2. Short communication: Amino acid supplementation and stage of lactation alter apparent utilization of nutrients by blood neutrophils from lactating dairy cows in vitro.

    PubMed

    Garcia, M; Elsasser, T H; Juengst, L; Qu, Y; Bequette, B J; Moyes, K M

    2016-05-01

    Glutamine is the preferred AA used by polymorphonuclear leukocytes (PMN) during the inflammatory response. However, the effect of other AA on bovine PMN response during inflammation and how this is altered by stage of lactation has not been fully elucidated. The objective of this study was to determine the effect of additional AA supplementation (pool of AA excluding Gln) on AA profiles, gene expression, and inflammatory function of PMN from dairy cows in early and mid lactation in vitro. We used 18 Holstein cows for this study. Polymorphonuclear leukocytes were isolated. Working solutions of AA (0 or 4 mM) and LPS (0 or 50μg/mL) were added to cell populations suspended in RPMI and incubated for 2h at 37°C. We used a subset of samples for gene and protein expression. Concentrations of AA in medium were determined using gas chromatography-mass spectrometry with norleucine as an internal standard. Apparent AA and glucose utilization were calculated by subtracting the concentration after from that of before incubation. Data were analyzed as a randomized block design. Challenge with LPS increased the expression of proinflammatory genes and AA supplementation decreased both the expression of some proinflammatory genes and the media concentrations of tumor necrosis factor-α. Neither stage of lactation, LPS challenge, nor AA supplementation altered the chemotactic or phagocytic abilities of PMN in vitro. Polymorphonuclear leukocytes supplemented with AA had greater concentrations and apparent utilization of most of the supplemented AA, whereas the unsupplemented group had greater apparent utilization of glucose. Alanine was not provided in the media but was present in spent media, and Ile, Gly, and Pro were greater in spent media than in media before incubation indicating synthesis of these AA. Regarding expression of genes involved in nutrient metabolism, the expression of G6PD, coding for the enzyme glucose 6-phosphate dehydrogenase, was increased and that of PDHA1, coding for the enzyme pyruvate dehydrogenase α 1, tended to increase with AA supplementation. Due to the lower concentration of tumor necrosis factor-α in media coupled with a downregulation of several proinflammatory genes, we concluded that AA, rather than Gln, alter the inflammatory response of bovine blood PMN. Independent from Gln, blood PMN from cows in early lactation may use certain AA as their primary carbon source for energy than cows in later lactation. Evaluating cows during the early postpartum period will provide additional information on the effect of stage of lactation and nutrient supplementation on PMN function. PMID:26971158

  3. Reconstruction of lactate utilization system in Pseudomonas putida KT2440: a novel biocatalyst for l-2-hydroxy-carboxylate production

    PubMed Central

    Wang, Yujiao; Lv, Min; Zhang, Yingxin; Xiao, Xieyue; Jiang, Tianyi; Zhang, Wen; Hu, Chunhui; Gao, Chao; Ma, Cuiqing; Xu, Ping

    2014-01-01

    As an important method for building blocks synthesis, whole cell biocatalysis is hindered by some shortcomings such as unpredictability of reactions, utilization of opportunistic pathogen, and side reactions. Due to its biological and extensively studied genetic background, Pseudomonas putida KT2440 is viewed as a promising host for construction of efficient biocatalysts. After analysis and reconstruction of the lactate utilization system in the P. putida strain, a novel biocatalyst that only exhibited NAD-independent d-lactate dehydrogenase activity was prepared and used in l-2-hydroxy-carboxylates production. Since the side reaction catalyzed by the NAD-independent l-lactate dehydrogenase was eliminated in whole cells of recombinant P. putida KT2440, two important l-2-hydroxy-carboxylates (l-lactate and l-2-hydroxybutyrate) were produced in high yield and high optical purity by kinetic resolution of racemic 2-hydroxy carboxylic acids. The results highlight the promise in biocatalysis by the biotechnologically important organism P. putida KT2440 through genomic analysis and recombination. PMID:25373400

  4. Genetics Home Reference: 2-methylbutyryl-CoA dehydrogenase deficiency

    MedlinePlus

    ... dehydrogenase deficiency 2-methylbutyryl glycinuria SBCADD short/branched-chain acyl-CoA dehydrogenase deficiency Related Information How are ... F. Isolated 2-methylbutyrylglycinuria caused by short/branched-chain acyl-CoA dehydrogenase deficiency: identification of a new ...

  5. MECHANISTIC ANALYSIS OF PYRUVATE DEHYDROGENASE KINASE

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Pyruvate dehydrogenase kinase (PDK) is the primary regulator of flux through the mitochondrial pyruvate dehydrogenase complex. The PDK is a member of the ATPase/kinase superfamily. Member proteins of this family are characterized by four signature sequences in the catalytic domain (N-, D-, F-, and G...

  6. VDAC electronics: 3. VDAC-Creatine kinase-dependent generation of the outer membrane potential in respiring mitochondria.

    PubMed

    Lemeshko, Victor V

    2016-07-01

    Mitochondrial energy in cardiac cells has been reported to be channeled into the cytosol through the intermembrane contact sites formed by the adenine nucleotide translocator, creatine kinase and VDAC. Computational analysis performed in this study showed a high probability of the outer membrane potential (OMP) generation coupled to such a mechanism of energy channeling in respiring mitochondria. OMPs, positive inside, calculated at elevated concentrations of creatine are high enough to restrict ATP release from mitochondria, to significantly decrease the apparent Km,ADP for state 3 respiration and to maintain low concentrations of Ca(2+) in the mitochondrial intermembrane space. An inhibition by creatine of Ca(2+)-induced swelling of isolated mitochondria and other protective effects of creatine reported in the literature might be explained by generated positive OMP. We suggest that VDAC-creatine kinase-dependent generation of OMP represents a novel physiological factor controlling metabolic state of mitochondria, cell energy channeling and resistance to death. PMID:27085978

  7. Enzymic studies on the biosynthesis of amino acids from lactate by Peptostreptococcus elsdenii

    PubMed Central

    Somerville, H. J.

    1968-01-01

    Cell-free extracts of Peptostreptococcus elsdenii, a strict anaerobe from the rumen, were examined for enzymes catalysing the steps in the biosynthesis from lactate of alanine, serine, aspartate and glutamate. Extracts contain the enzymes necessary for the formation of alanine from lactate via pyruvate. The presence of enzymes catalysing the interconversion of phosphoglycerate and phosphohydroxypyruvate, the transamination of the latter to phosphoserine and the cleavage of phosphoserine to serine and inorganic phosphate was demonstrated, suggesting that serine is formed via these intermediates. `Malic' enzyme, malate dehydrogenase and glutamate–oxaloacetate transaminase are present in extracts and could account for aspartate formation. The extracts catalyse all of the steps of the tricarboxylic acid pathway leading from oxaloacetate plus acetate to glutamate. Together with substantive data from previous radioactive tracer studies the results provide strong evidence that these four amino acids are synthesized in this strict anaerobe by pathways closely similar to those operating in aerobic and facultatively aerobic organisms. PMID:5690537

  8. Evaluation of lactate dehydrogenase activity as an index of cervical malignancy.

    PubMed

    Gerolymatos, A; Fotiou, S; Tserkezoglou, A; Somarakis, M; Katsilieris, J; Kotsalis, N; Aravantinos, D

    1991-01-01

    The diagnostic accuracy of an investigational test for cervix cancer screening is studied. The method involves a vaginal tampon that changes colour in relation to LDH activity and can detect preinvasive and invasive cervical lesions. The test was applied in 50 women with CIN, 50 women with histologically proved cervical cancer and in 500 women with no history of malignancy. The test was positive in 54% of CINs and 86% of cervix cancer patients, while it was not specific in 16% and 4% respectively. Among 268 healthy controls the test results were negative in 77.99% and false positive in 12.31%. The test can be performed any day of the menstrual cycle apart from the time of menstruation. It can also be performed, without any serious problem of misinterpretation in women suffering from myomas, vaginal relaxation or menstrual disorders. On the contrary, the test should be avoided if vaginitis or cervicitis are present, since false positive conclusions might be drawn. The test results suggest that the sensitivity of this method was 77% and the specificity 86% if we exclude the benign conditions that influence or possibly influence the colour indication of the tampon. PMID:1809580

  9. Relationship between polymorphisms in lactate dehydrogenase B gene and milk characteristics in beef cows

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Cytochrome P450s are a group of heme-containing monooxygenases necessary for the oxidative metabolism of foreign biological substances. Our goal was to determine the frequency of single nucleotide polymorphism (SNP) 994 in the CYP3A28 sequence of three breed types of cattle. The distribution of geno...

  10. Affinity Chromatography of Lactate Dehydrogenase: An Experiment for the Undergraduate Biochemistry Laboratory.

    ERIC Educational Resources Information Center

    Anderson, Alexander J.

    1988-01-01

    Discusses a laboratory technique of enzyme purification by affinity chromatography as part of an undergraduate biochemical methodology course. Provides preparation details of the rat muscle homogenate and reagents. Proposes column requirements and assaying information. (MVL)

  11. Inhibition of Rhizopus Lactate Dehydrogenase by Fructose 1,6-bisphosphate

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The study of the filamentous fungus Rhizopus is of significant value because of the organism’s industrial importance, clinical detriment, and agricultural problems. Yet, research has yielded very few advances that allow site directed integration of DNA used for transformation. This is because plas...

  12. Serum Lactate Dehydrogenase in Non-Hodgkin's Lymphoma: A Prognostic Indicator.

    PubMed

    Yadav, Charu; Ahmad, Afzal; D'Souza, Benedicta; Agarwal, Ashish; Nandini, M; Ashok Prabhu, K; D'Souza, Vivian

    2016-04-01

    Non-Hodgkin's lymphoma constitutes a group of disorders originating from the malignant transformation of lymphocytes and involving either the lymph nodes or extranodal sites. NHL commonly presents in the sixth to seventh decade of life with a male preponderance (50-75 %). Recent studies have shown importance of serum LDH in prognosis of NHL. Authors report a case of a 63 year old male presenting with complaints of fever and backache for past 4 months. General and systemic examination revealed bilateral axillary lymphadenopathy and splenomegaly respectively. Serum LDH level was highly elevated (3441 U/l). Excisional axillary and bone marrow biopsy were done before oncology referral. Complete workup revealed diffuse Non-Hodgkin's lymphoma with bone marrow infiltration. Patient died because of acute renal failure due to NHL and DM 2 (Type 2 diabetes mellitus). PMID:27069334

  13. Salivary Lactate Dehydrogenase (LDH)- A Novel Technique in Oral Cancer Detection and Diagnosis

    PubMed Central

    Kannabiran, Jayanthi; Rao, Mahesh Dathu

    2016-01-01

    Introduction Oral squamous cell carcinoma (OSCC) is the sixth most common malignancy which is a major cause for cancer morbidity and mortality worldwide. Early diagnosis and intervention improves the overall survival rate. Aim The current study was done to evaluate the accuracy of salivary LDH as a potential biomarker for diagnosis of OSCC and to correlate the levels of salivary LDH with the histological differentiation of the tumour. Materials and Methods Thirty patients visiting the outpatient department diagnosed clinically and histologically with OSCC were selected for the study with a control group of 20 patients. Unstimulated salivary samples collected from the selected patients were centrifuged and processed. Readings of enzyme activity in the salivary samples was established through auto analysis using International Federation of Clinical Chemistry (IFCC) method. Levels of the enzyme activity in both the control and the study group were compared and statistically analysed using student t-test. The three subgroups were also compared and statistically analysed. Results The results showed a mean value of 497.00 with a SD of 51.75 among the control group and a mean value of 1225.40 with a SD of 221.79 among the cases with a p-value of 0.0001 which was statistically significant. Furthermore, when the LDH values for the various grades of OSCC were compared, the mean values were 1049.07, 1309.50 and 1586.20 respectively, for well differentiated, moderately differentiated and poorly differentiated carcinoma. Conclusion The p-value thus obtained revealed LDH values which were significantly higher in patients with OSCC and furthermore the levels significantly correlated with the histopathological grade of the tumour. PMID:27042582

  14. Lactate dehydrogenase and caspase activity in nasopharyngeal secretions are predictors of bronchiolitis severity

    PubMed Central

    Mehta, Reena; Scheffler, Margaret; Tapia, Lorena; Aideyan, Letisha; Patel, Kirtida D; Jewell, Alan M; Avadhanula, Vasanthi; Mei, Minghua; Garofalo, Roberto P; Piedra, Pedro A

    2014-01-01

    Background Bronchiolitis is the leading cause of hospitalization in infants. Biomarkers of disease severity might help in clinical management. Objective To determine the clinical predictiveness of NW-LDH, NW-caspase 3/7, and NW-LDH/NW-caspase 3/7 ratio in bronchiolitis. Methods Previously healthy children less than 24months of age with bronchiolitis were recruited from the Texas Children's emergency room and intensive care unit from October 2010 to April 2011. Demographic, clinical information, and NW samples were obtained at enrollment. NW samples were analyzed for respiratory viruses, caspase 3/7, and LDH. Results A viral pathogen was detected in 916% of 131 children, with the most common being respiratory syncytial virus and human rhinovirus. A single infection was found in 618% of subjects and co-infection in 298%. Children admitted to ICU had significantly higher NW-LDH than children sent home from the ER or admitted to the general floor (P=002). Children infected with RSV had the highest NW-LDH concentration (P=003) compared with other viral infections. NW-LDH and NW-caspase were significantly correlated (r=077, P<00001). The univariate models showed NW-LDH and NW-LDH/NW- caspase 3/7 ratio were directly associated with hospitalization. Mutivariate regression analyses suggested a complex interaction between the biomarkers, demographics, and disposition. Conclusions NW-LDH, NW-caspase 3/7 and NW-LDH/NW-caspase 3/7 ratio and their interactions with demographic factors are predictive of bronchiolitis severity and can help distinguish children requiring ICU-level care from those admitted to the general floor, or discharged home from the emergency center. PMID:25132512

  15. Pyruvate and Lactate Metabolism by Shewanella oneidensis MR-1 under Fermentation, Oxygen Limitation, and Fumarate Respiration Conditions

    SciTech Connect

    Pinchuk, Grigoriy E.; Geydebrekht, Oleg V.; Hill, Eric A.; Reed, Jennifer L.; Konopka, Allan; Beliaev, Alex S.; Fredrickson, Jim K.

    2011-12-01

    Shewanella oneidensis MR-1 is a facultative anaerobe that derives energy by coupling organic matter oxidation to the reduction of wide range of electron acceptors. Here, we quantitatively assessed lactate and pyruvate metabolism of MR-1 under three distinct conditions: electron acceptor limited growth on lactate with O2; lactate with fumarate; and pyruvate fermentation. The latter does not support growth but provides energy for cell survival. Using physiological and genetic approaches combined with flux balance analysis, we showed that the proportion of ATP produced by substrate-level phosphorylation varied from 33% to 72.5% of that needed for growth depending on the electron acceptor nature and availability. While being indispensible for growth, respiration of fumarate does not contribute significantly to ATP generation and likely serves to remove formate, a product of pyruvate formate-lyase-catalyzed pyruvate disproportionation. Under both tested respiratory conditions S. oneidensis MR-1 carried out incomplete substrate oxidation, whereby the TCA cycle did not contribute significantly. Pyruvate dehydrogenase was not involved in lactate metabolism under O2 limitation but was required for anaerobic growth likely by supplying reducing equivalents for biosynthesis. The results suggest that pyruvate fermentation by S. oneidensis MR-1 cells represents a combination of substrate-level phosphorylation and respiration, where pyruvate serves as electron donor and electron acceptor. Pyruvate reduction to lactate at the expense of formate oxidation is catalyzed by recently described new type of oxidative NAD(P)H independent D-lactate dehydrogenase (Dld-II). The results further indicate that pyruvate reduction coupled to formate oxidation may be accompanied by proton motive force generation.

  16. Pyruvate and lactate metabolism by Shewanella oneidensis MR-1 under fermentation, oxygen limitation, and fumarate respiration conditions.

    PubMed

    Pinchuk, Grigoriy E; Geydebrekht, Oleg V; Hill, Eric A; Reed, Jennifer L; Konopka, Allan E; Beliaev, Alexander S; Fredrickson, Jim K

    2011-12-01

    Shewanella oneidensis MR-1 is a facultative anaerobe that derives energy by coupling organic matter oxidation to the reduction of a wide range of electron acceptors. Here, we quantitatively assessed the lactate and pyruvate metabolism of MR-1 under three distinct conditions: electron acceptor-limited growth on lactate with O(2), lactate with fumarate, and pyruvate fermentation. The latter does not support growth but provides energy for cell survival. Using physiological and genetic approaches combined with flux balance analysis, we showed that the proportion of ATP produced by substrate-level phosphorylation varied from 33% to 72.5% of that needed for growth depending on the electron acceptor nature and availability. While being indispensable for growth, the respiration of fumarate does not contribute significantly to ATP generation and likely serves to remove formate, a product of pyruvate formate-lyase-catalyzed pyruvate disproportionation. Under both tested respiratory conditions, S. oneidensis MR-1 carried out incomplete substrate oxidation, whereby the tricarboxylic acid (TCA) cycle did not contribute significantly. Pyruvate dehydrogenase was not involved in lactate metabolism under conditions of O(2) limitation but was required for anaerobic growth, likely by supplying reducing equivalents for biosynthesis. The results suggest that pyruvate fermentation by S. oneidensis MR-1 cells represents a combination of substrate-level phosphorylation and respiration, where pyruvate serves as an electron donor and an electron acceptor. Pyruvate reduction to lactate at the expense of formate oxidation is catalyzed by a recently described new type of oxidative NAD(P)H-independent d-lactate dehydrogenase (Dld-II). The results further indicate that pyruvate reduction coupled to formate oxidation may be accompanied by the generation of proton motive force. PMID:21965410

  17. Effects of decreased lactate accumulation after dichloroacetate administration on exercise training–induced mitochondrial adaptations in mouse skeletal muscle

    PubMed Central

    Hoshino, Daisuke; Tamura, Yuki; Masuda, Hiroyuki; Matsunaga, Yutaka; Hatta, Hideo

    2015-01-01

    Recent studies suggested that lactate accumulation can be a signal for mitochondrial biogenesis in skeletal muscle. We investigated whether reductions in lactate concentrations in response to dichloroacetate (DCA), an activator of pyruvate dehydrogenase, attenuate mitochondrial adaptations after exercise training in mice. We first confirmed that DCA administration (200 mg/kg BW by i.p. injection) 10 min before exercise decreased muscle and blood lactate concentrations after high-intensity interval exercise (10 bouts of 1 min treadmill running at 40 m/min with a 1 min rest). At the same time, exercise-induced signal cascades did not change by pre-exercise DCA administration. These results suggested that DCA administration affected only lactate concentrations after exercise. We next examined the effects of acute DCA administration on mRNA expressions involved with mitochondrial biogenesis after same high-intensity interval exercise and the effects of chronic DCA administration on mitochondrial adaptations after high-intensity interval training (increasing intensity from 38 to 43 m/min by the end of training period). Acute DCA administration did not change most of the exercise-induced mRNA upregulation. These data suggest that lactate reductions by DCA administration did not affect transcriptional activation after high-intensity interval exercise. However, chronic DCA administration attenuated, in part, mitochondrial adaptations such as training-induced increasing rates of citrate synthase (P = 0.06), β-hydroxyacyl CoA dehydrogenase activity (P < 0.05), cytochrome c oxidase IV (P < 0.05) and a fatty acid transporter, fatty acid translocase/CD36 (P < 0.05), proteins after exercise training. These results suggest that lactate accumulation during high-intensity interval exercise may be associated with mitochondrial adaptations after chronic exercise training. PMID:26416973

  18. Maternal flaxseed diet during lactation changes adrenal function in adult male rat offspring.

    PubMed

    Figueiredo, Mariana Sarto; da Conceição, Ellen Paula Santos; de Oliveira, Elaine; Lisboa, Patricia Cristina; de Moura, Egberto Gaspar

    2015-10-14

    Flaxseed (Linum usitatissimum L.) has been a focus of interest in the field of functional foods because of its potential health benefits. However, we hypothesised that maternal flaxseed intake during lactation could induce several metabolic dysfunctions in adult offspring. In the present study, we aimed to characterise the adrenal function of adult offspring whose dams were supplemented with whole flaxseed during lactation. At birth, lactating Wistar rats were divided into two groups: rats from dams fed the flaxseed diet (FLAX) with 25% of flaxseed and controls dams. Pups received standard diet after weaning and male offspring were killed at age 180 days old to collect blood and tissues. We evaluated body weight and food intake during development, corticosteronaemia, adrenal catecholamine content, hepatic cholesterol, TAG and glycogen contents, and the protein expression of corticotropin-releasing hormone (CRH), adrenocorticotropic hormone (ACTH), 11-β-hydroxysteroid dehydrogenase type 1 (11β-HSD1) and adrenaline β2 receptor at postnatal day 180 (PN180). After weaning, pups from the FLAX group had a higher body weight (+10 %) and food intake (+10%). At PN180, the FLAX offspring exhibited higher serum corticosterone (+48%) and lower adrenal catecholamine ( - 23%) contents, lower glycogen ( - 30%), higher cholesterol (4-fold increase) and TAG (3-fold-increase) contents in the liver, and higher 11β-HSD1 (+62%) protein expression. Although the protein expression of hypothalamic CRH was unaffected, the FLAX offspring had lower protein expression of pituitary ACTH ( - 34%). Therefore, induction of hypercorticosteronaemia by dietary flaxseed during lactation may be due to an increased hepatic activation of 11β-HSD1 and suppression of ACTH. The changes in the liver fat content of the FLAX group are suggestive of steatosis, in which hypercorticosteronaemia may play an important role. Thus, it is recommended that lactating women restrict the intake of flaxseed during lactation. PMID:26337632

  19. Benzyl alcohol dehydrogenase and benzaldehyde dehydrogenase II from Acinetobacter calcoaceticus. Substrate specificities and inhibition studies.

    PubMed Central

    MacKintosh, R W; Fewson, C A

    1988-01-01

    The apparent Km and maximum velocity values of benzyl alcohol dehydrogenase and benzaldehyde dehydrogenase II from Acinetobacter calcoaceticus were determined for a range of alcohols and aldehydes and the corresponding turnover numbers and specificity constants were calculated. Benzyl alcohol was the most effective alcohol substrate for benzyl alcohol dehydrogenase. Perillyl alcohol was the second most effective substrate, and was the only non-aromatic alcohol oxidized. The other substrates of benzyl alcohol dehydrogenase were all aromatic in nature, with para-substituted derivatives of benzyl alcohol being better substrates than other derivatives. Coniferyl alcohol and cinnamyl alcohol were also substrates. Benzaldehyde was much the most effective substrate for benzaldehyde dehydrogenase II. Benzaldehydes with a single small substituent group in the meta or para position were better substrates than any other benzaldehyde derivatives. Benzaldehyde dehydrogenase II could also oxidize the aliphatic aldehydes hexan-1-al and octan-1-al, although poorly. Benzaldehyde dehydrogenase II was substrate-inhibited by benzaldehyde when the assay concentration exceeded approx. 10 microM. Benzaldehyde dehydrogenase II, but not benzyl alcohol dehydrogenase, exhibited esterase activity with 4-nitrophenyl acetate as substrate. Both benzyl alcohol dehydrogenase and benzaldehyde dehydrogenase II were inhibited by the thiol-blocking reagents iodoacetate, iodoacetamide, 4-chloromercuribenzoate and N-ethylmaleimide. Benzyl alcohol or benzaldehyde respectively protected against these inhibitions. NAD+ also gave some protection. Neither benzyl alcohol dehydrogenase nor benzaldehyde dehydrogenase II was inhibited by the metal-ion-chelating agents EDTA, 2,2'-bipyridyl, pyrazole or 2-phenanthroline. Neither enzyme was inhibited by a range of plausible metabolic inhibitors such as mandelate, phenylglyoxylate, benzoate, succinate, acetyl-CoA, ATP or ADP. Benzaldehyde dehydrogenase II was sensitive to inhibition by several aromatic aldehydes; in particular, ortho-substituted benzaldehydes such as 2-bromo-, 2-chloro- and 2-fluoro-benzaldehydes were potent inhibitors of the enzyme. PMID:3060114

  20. Exogenous lactate supply affects lactate kinetics of rainbow trout, not swimming performance

    PubMed Central

    Omlin, Teye; Langevin, Karolanne

    2014-01-01

    Intense swimming causes circulatory lactate accumulation in rainbow trout because lactate disposal (Rd) is not stimulated as strongly as lactate appearance (Ra). This mismatch suggests that maximal Rd is limited by tissue capacity to metabolize lactate. This study uses exogenous lactate to investigate what constrains maximal Rd and minimal Ra. Our goals were to determine how exogenous lactate affects: 1) Ra and Rd of lactate under baseline conditions or during graded swimming, and 2) exercise performance (critical swimming speed, Ucrit) and energetics (cost of transport, COT). Results show that exogenous lactate allows swimming trout to boost maximal Rd lactate by 40% and reach impressive rates of 56 μmol·kg−1·min−1. This shows that the metabolic capacity of tissues for lactate disposal is not responsible for setting the highest Rd normally observed after intense swimming. Baseline endogenous Ra (resting in normoxic water) is not significantly reduced by exogenous lactate supply. Therefore, trout have an obligatory need to produce lactate, either as a fuel for oxidative tissues and/or from organs relying on glycolysis. Exogenous lactate does not affect Ucrit or COT, probably because it acts as a substitute for glucose and lipids rather than extra fuel. We conclude that the observed 40% increase in Rd lactate is made possible by accelerating lactate entry into oxidative tissues via monocarboxylate transporters (MCTs). This observation together with the weak expression of MCTs and the phenomenon of white muscle lactate retention show that lactate metabolism of rainbow trout is significantly constrained by transmembrane transport. PMID:25121611

  1. Exogenous lactate supply affects lactate kinetics of rainbow trout, not swimming performance.

    PubMed

    Omlin, Teye; Langevin, Karolanne; Weber, Jean-Michel

    2014-10-15

    Intense swimming causes circulatory lactate accumulation in rainbow trout because lactate disposal (Rd) is not stimulated as strongly as lactate appearance (Ra). This mismatch suggests that maximal Rd is limited by tissue capacity to metabolize lactate. This study uses exogenous lactate to investigate what constrains maximal Rd and minimal Ra. Our goals were to determine how exogenous lactate affects: 1) Ra and Rd of lactate under baseline conditions or during graded swimming, and 2) exercise performance (critical swimming speed, Ucrit) and energetics (cost of transport, COT). Results show that exogenous lactate allows swimming trout to boost maximal Rd lactate by 40% and reach impressive rates of 56 μmol·kg(-1)·min(-1). This shows that the metabolic capacity of tissues for lactate disposal is not responsible for setting the highest Rd normally observed after intense swimming. Baseline endogenous Ra (resting in normoxic water) is not significantly reduced by exogenous lactate supply. Therefore, trout have an obligatory need to produce lactate, either as a fuel for oxidative tissues and/or from organs relying on glycolysis. Exogenous lactate does not affect Ucrit or COT, probably because it acts as a substitute for glucose and lipids rather than extra fuel. We conclude that the observed 40% increase in Rd lactate is made possible by accelerating lactate entry into oxidative tissues via monocarboxylate transporters (MCTs). This observation together with the weak expression of MCTs and the phenomenon of white muscle lactate retention show that lactate metabolism of rainbow trout is significantly constrained by transmembrane transport. PMID:25121611

  2. Targeting metabolic flexibility by simultaneously inhibiting respiratory complex I and lactate generation retards melanoma progression

    PubMed Central

    Chaube, Balkrishna; Malvi, Parmanand; Singh, Shivendra Vikram; Mohammad, Naoshad; Meena, Avtar Singh; Bhat, Manoj Kumar

    2015-01-01

    Melanoma is a largely incurable skin malignancy owing to the underlying molecular and metabolic heterogeneity confounded by the development of resistance. Cancer cells have metabolic flexibility in choosing either oxidative phosphorylation (OXPHOS) or glycolysis for ATP generation depending upon the nutrient availability in tumor microenvironment. In this study, we investigated the involvement of respiratory complex I and lactate dehydrogenase (LDH) in melanoma progression. We show that inhibition of complex I by metformin promotes melanoma growth in mice via elevating lactate and VEGF levels. In contrast, it leads to the growth arrest in vitro because of enhanced extracellular acidification as a result of increased glycolysis. Inhibition of LDH or lactate generation causes decrease in glycolysis with concomitant growth arrest both in vitro and in vivo. Blocking lactate generation in metformin-treated melanoma cells results in diminished cell proliferation and tumor progression in mice. Interestingly, inhibition of either LDH or complex I alone does not induce apoptosis, whereas inhibiting both together causes depletion in cellular ATP pool resulting in metabolic catastrophe induced apoptosis. Overall, our study suggests that LDH and complex I play distinct roles in regulating glycolysis and cell proliferation. Inhibition of these two augments synthetic lethality in melanoma. PMID:26484566

  3. Automated urinalysis technique determines concentration of creatine and creatinine by colorimetry

    NASA Technical Reports Server (NTRS)

    Rho, J. H.

    1967-01-01

    Continuous urinalysis technique is useful in the study of muscle wastage in primates. Creatinine concentration in urine is determined in an aliquot mixture by a color reaction. Creatine is determined in a second aliquot by converting it to creatinine and measuring the difference in color intensity between the two aliquots.

  4. The Effects of Creatine Supplementation on Exercise-Induced Muscle Damage.

    ERIC Educational Resources Information Center

    Rawson, Eric S.; Gunn, Bridget; Clarkson, Priscilla M.

    2001-01-01

    Investigated the effects of oral creatine (Cr) supplementation on markers of exercise-induced muscle damage following high-force eccentric exercise in men randomly administered Cr or placebo. Results indicated that 5 days of Cr supplementation did not reduce indirect makers of muscle damage or enhance recovery from high-force eccentric exercise.…

  5. Creatine Kinase Activity Weakly Correlates to Volume Completed Following Upper Body Resistance Exercise

    ERIC Educational Resources Information Center