The Efficacy of MAG-DHA for Correcting AA/DHA Imbalance of Cystic Fibrosis Patients

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Caroline Morin

2018-05-01

Full Text Available Omega-3 polyunsaturated fatty acid (n-3 PUFA supplementations are thought to improve essential fatty acid deficiency (EFAD as well as reduce inflammation in Cystic Fibrosis (CF, but their effectiveness in clinical studies remains unknown. The aim of the study was to determine how the medical food containing docosahexaenoic acid monoglyceride (MAG-DHA influenced erythrocyte fatty acid profiles and the expression levels of inflammatory circulating mediators. We conducted a randomized, double blind, pilot trial including fifteen outpatients with Cystic Fibrosis, ages 18–48. The patients were divided into 2 groups and received MAG-DHA or a placebo (sunflower oil for 60 days. Patients took 8 × 625 mg MAG-DHA softgels or 8 × 625 mg placebo softgels every day at bedtime for 60 days. Lipid analyses revealed that MAG-DHA increased docosahexaenoic acid (DHA levels and decrease arachidonic acid (AA ratio (AA/DHA in erythrocytes of CF patients following 1 month of daily supplementation. Data also revealed a reduction in plasma human leukocyte elastase (pHLE complexes and interleukin-6 (IL-6 expression levels in blood samples of MAG-DHA supplemented CF patients. This pilot study indicates that MAG-DHA supplementation corrects erythrocyte AA/DHA imbalance and may exert anti-inflammatory properties through the reduction of pHLE complexes and IL6 in blood samples of CF patients. Trial registration: Pro-resolving Effect of MAG-DHA in Cystic Fibrosis (PREMDIC, NCT02518672.

Dietary DHA/EPA ratio affected tissue fatty acid profiles, antioxidant capacity, hematological characteristics and expression of lipid-related genes but not growth in juvenile black seabream (Acanthopagrus schlegelii).

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Jin, Min; Monroig, Óscar; Lu, You; Yuan, Ye; Li, Yi; Ding, Liyun; Tocher, Douglas R; Zhou, Qicun

2017-01-01

An 8-week feeding trial was conducted to investigate the effects of dietary docosahexaenoic to eicosapentaenoic acid ratio (DHA/EPA) on growth performance, fatty acid profiles, antioxidant capacity, hematological characteristics and expression of some lipid metabolism related genes of juvenile black seabream (Acanthopagrus schlegelii) of initial weight 9.47 ± 0.03 g. Five isonitrogenous and isolipidic diets (45% crude protein and 14% crude lipid) were formulated to contain graded DHA/EPA ratios of 0.65, 1.16, 1.60, 2.03 and 2.67. There were no differences in growth performance and feed utilization among treatments. Fish fed higher DHA/EPA ratios had higher malondialdehyde (MDA) contents in serum than lower ratios. Serum triacylglycerol (TAG) content was significantly higher in fish fed the lowest DHA/EPA ratio. Tissue fatty acid profiles reflected the diets despite down-regulation of LC-PUFA biosynthesis genes, fatty acyl desaturase 2 (fads2) and elongase of very long-chain fatty acids 5 (elovl5), by high DHA/EPA ratios. Expression of acetyl-CoA carboxylase alpha (accα) and carnitine palmitoyl transferase 1A (cpt1a) were up-regulated by high DHA/EPA ratio, whereas sterol regulatory element-binding protein-1 (srebp-1) and hormone-sensitive lipase (hsl) were down-regulated. Fatty acid synthase (fas), 6-phosphogluconate dehydrogenase (6pgd) and peroxisome proliferator-activated receptor alpha (pparα) showed highest expression in fish fed intermediate (1.16) DHA/EPA ratio. Overall, this study indicated that dietary DHA/EPA ratio affected fatty acid profiles and significantly influenced lipid metabolism including LC-PUFA biosynthesis and other anabolic and catabolic pathways, and also had impacts on antioxidant capacity and hematological characteristics.

Catalytic properties of thermophilic lactate dehydrogenase and halophilic malate dehydrogenase at high temperature and low water activity.

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Hecht, K; Wrba, A; Jaenicke, R

1989-07-15

Thermophilic lactate dehydrogenases from Thermotoga maritima and Bacillus stearothermophilus are stable up to temperature limits close to the optimum growth temperature of their parent organisms. Their catalytic properties are anomalous in that Km shows a drastic increase with increasing temperature. At low temperatures, the effect levels off. Extreme halophilic malate dehydrogenase from Halobacterium marismortui exhibits a similar anomaly. Increasing salt concentration (NaCl) leads to an optimum curve for Km, oxaloacctate while Km, NADH remains constant. Previous claims that the activity of halophilic malate dehydrogenase shows a maximum at 1.25 M NaCl are caused by limiting substrate concentration; at substrate saturation, specific activity of halophilic malate dehydrogenase reaches a constant value at ionic strengths I greater than or equal to 1 M. Non-halophilic (mitochondrial) malate dehydrogenase shows Km characteristics similar to those observed for the halophilic enzyme. The drastic decrease in specific activity of the mitochondrial enzyme at elevated salt concentrations is caused by the salt-induced increase in rigidity of the enzyme, rather than gross structural changes.

Maternal liver docosahexaenoic acid (DHA) stores are increased via higher serum unesterified DHA uptake in pregnant long Evans rats.

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Metherel, Adam H; Kitson, Alex P; Domenichiello, Anthony F; Lacombe, R J Scott; Hopperton, Kathryn E; Trépanier, Marc-Olivier; Alashmali, Shoug M; Lin, Lin; Bazinet, Richard P

2017-08-01

Maternal docosahexaenoic acid (DHA, 22:6n-3) supplies the developing fetus during pregnancy; however, the mechanisms are unclear. We utilized pregnant rats to determine rates of DHA accretion, tissue unesterified DHA uptake and whole-body DHA synthesis-secretion. Female rats maintained on a DHA-free, 2% α-linolenic acid diet were either:1) sacrificed at 56 days for baseline measures, 2) mated and sacrificed at 14-18 days of pregnancy or 3) or sacrificed at 14-18 days as age-matched virgin controls. Maternal brain, adipose, liver and whole body fatty acid concentrations was determined for balance analysis, and kinetic modeling was used to determine brain and liver plasma unesterified DHA uptake and whole-body DHA synthesis-secretion rates. Total liver DHA was significantly higher in pregnant (95±5 μmol) versus non-pregnant (49±5) rats with no differences in whole-body DHA synthesis-secretion rates. However, liver uptake of plasma unesterified DHA was 3.8-fold higher in pregnant animals compared to non-pregnant controls, and periuterine adipose DHA was lower in pregnant (0.89±0.09 μmol/g) versus non-pregnant (1.26±0.06) rats. In conclusion, higher liver DHA accretion during pregnancy appears to be driven by higher unesterified DHA uptake, potentially via DHA mobilization from periuterine adipose for delivery to the fetus during the brain growth spurt. Copyright © 2017 Elsevier Inc. All rights reserved.

DHA suppresses Prevotella intermedia lipopolysaccharide-induced production of proinflammatory mediators in murine macrophages.

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Choi, Eun-Young; Jin, Ji-Young; Choi, Jeom-Il; Choi, In Soon; Kim, Sung-Jo

2014-04-14

Several reports have indicated that dietary intake of DHA is associated with lower prevalence of periodontitis. In the present study, we investigated the effect of DHA on the production of proinflammatory mediators in murine macrophage-like RAW264.7 cells stimulated with lipopolysaccharide (LPS) isolated from Prevotella intermedia, a pathogen implicated in inflammatory periodontal disease, and its mechanisms of action. LPS was isolated from lyophilised P. intermedia ATCC 25,611 cells using the standard hot-phenol-water protocol. Culture supernatants were collected and assayed for NO, IL-1β and IL-6. Real-time PCR analysis was carried out to detect the expression of inducible NO synthase (iNOS), IL-1β, IL-6 and haeme oxygenase-1 (HO-1) mRNA. Immunoblot analysis was carried out to quantify the expression of iNOS and HO-1 protein and concentrations of signalling proteins. DNA-binding activities of NF-κB subunits were determined using an ELISA-based assay kit. DHA significantly attenuated the production of NO, IL-1β and IL-6 at both gene transcription and translation levels in P. intermedia LPS-activated RAW264.7 cells. DHA induced the expression of HO-1 in cells treated with P. intermedia LPS. Selective inhibition of HO-1 activity by tin protoporphyrin IX significantly mitigated the inhibitory effects of DHA on LPS-induced NO production. DHA significantly attenuated the phosphorylation of c-Jun N-terminal kinase induced by LPS. In addition, DHA suppressed the transcriptional activity of NF-κB by regulating the nuclear translocation and DNA-binding activity of NF-κB p50 subunit and inhibited the phosphorylation of signal transducer and activator of transcription 1. Further in vivo studies are needed to better evaluate the potential of DHA in humans as a therapeutic agent to treat periodontal disease.

Toxicity of Nitrification Inhibitors on Dehydrogenase Activity in Soils

OpenAIRE

Ferisman Tindaon; Gero Benckiser; Johannes C. G. Ottow

2011-01-01

The objective of this research was to determine the effects of nitrification inhibitors (NIs) such as 3,4-dimethylpyrazolephosphate=DMPP, 4-Chlor-methylpyrazole phosphate=ClMPP and dicyandiamide,DCD) which might be expected to inhibit microbial activity, on dehydrogenase activity (DRA),in three different soils in laboratory conditions. Dehydrogenase activity were assessed via reduction of 2-p-Iodophenyl-3-p-nitrophenyl-5-phenyltetrazoliumchloride (INT). The toxicity and dose response curve of...

Dihydroazulene/Vinylheptafulvene (DHA/VHF)

DEFF Research Database (Denmark)

Vlasceanu, Alexandru

A theoretical and experimental investigation of conformational modifications on the thermodynamic, optical, and switching properties of dihydroazulene/vinylheptafulvene (DHA/VHF) photoswitches, in the context of molecular solar thermal (MOST) systems, is described herein. The optical properties...... of monomeric DHA/VHF systems are found to be strongly dependent on structural changes which can be tuned via steric modifications. This correlation is then used to infer structural features of more complex, macrocyclic DHA/VHF systems based on their optical properties. The introduction of macrocyclic ring...... strain is furthermore found to significantly influence the switching behavior of DHA/VHF moieties compared to non-cyclized systems. The thermal ring closure of macrocyclic VHF-VHF systems is found to occur in a stepwise manner, enabling the release of the energy on both a fast and slow timescale...

Docosahexaenoic acid (DHA) supplementation in pregnancy differentially modulates arachidonic acid and DHA status across FADS genotypes in pregnancy.

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Scholtz, S A; Kerling, E H; Shaddy, D J; Li, S; Thodosoff, J M; Colombo, J; Carlson, S E

2015-03-01

Some FADS alleles are associated with lower DHA and ARA status assessed by the relative amount of arachidonic acid (ARA) and docosahexaenoic acid (DHA) in plasma and red blood cell (RBC) phospholipids (PL). We determined two FADS single nucleotide polymorphisms (SNPs) in a cohort of pregnant women and examined the relationship of FADS1rs174533 and FADS2rs174575 to DHA and ARA status before and after supplementation with 600mg per day of DHA. The 205 pregnant women studied were randomly assigned to placebo (mixed soy and corn oil) (n=96) or 600mg algal DHA (n=109) in 3 capsules per day for the last two trimesters of pregnancy. Women homozygous for the minor allele of FADS1rs174533 (but not FADS2rs174575) had lower DHA and ARA status at baseline. At delivery, minor allele homozygotes of FADS1rs174533 in the placebo group had lower RBC-DHA compared to major-allele carriers (P=0.031), while in the DHA-supplemented group, all genotypes had higher DHA status compared to baseline (P=0.001) and status did not differ by genotype (P=0.941). Surprisingly, DHA but not the placebo decreased ARA status of minor allele homozygotes of both FADS SNPs but not major allele homozygotes at delivery. Any physiological effects of changing the DHA to ARA ratio by increasing DHA intake appears to be greater in minor allele homozygotes of some FADS SNPs. Copyright © 2014 Elsevier Ltd. All rights reserved.

DHA Effects in Brain Development and Function

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Lotte Lauritzen

2016-01-01

Full Text Available Docosahexaenoic acid (DHA is a structural constituent of membranes specifically in the central nervous system. Its accumulation in the fetal brain takes place mainly during the last trimester of pregnancy and continues at very high rates up to the end of the second year of life. Since the endogenous formation of DHA seems to be relatively low, DHA intake may contribute to optimal conditions for brain development. We performed a narrative review on research on the associations between DHA levels and brain development and function throughout the lifespan. Data from cell and animal studies justify the indication of DHA in relation to brain function for neuronal cell growth and differentiation as well as in relation to neuronal signaling. Most data from human studies concern the contribution of DHA to optimal visual acuity development. Accumulating data indicate that DHA may have effects on the brain in infancy, and recent studies indicate that the effect of DHA may depend on gender and genotype of genes involved in the endogenous synthesis of DHA. While DHA levels may affect early development, potential effects are also increasingly recognized during childhood and adult life, suggesting a role of DHA in cognitive decline and in relation to major psychiatric disorders.

DHA Effects in Brain Development and Function

Science.gov (United States)

Lauritzen, Lotte; Brambilla, Paolo; Mazzocchi, Alessandra; Harsløf, Laurine B. S.; Ciappolino, Valentina; Agostoni, Carlo

2016-01-01

Docosahexaenoic acid (DHA) is a structural constituent of membranes specifically in the central nervous system. Its accumulation in the fetal brain takes place mainly during the last trimester of pregnancy and continues at very high rates up to the end of the second year of life. Since the endogenous formation of DHA seems to be relatively low, DHA intake may contribute to optimal conditions for brain development. We performed a narrative review on research on the associations between DHA levels and brain development and function throughout the lifespan. Data from cell and animal studies justify the indication of DHA in relation to brain function for neuronal cell growth and differentiation as well as in relation to neuronal signaling. Most data from human studies concern the contribution of DHA to optimal visual acuity development. Accumulating data indicate that DHA may have effects on the brain in infancy, and recent studies indicate that the effect of DHA may depend on gender and genotype of genes involved in the endogenous synthesis of DHA. While DHA levels may affect early development, potential effects are also increasingly recognized during childhood and adult life, suggesting a role of DHA in cognitive decline and in relation to major psychiatric disorders. PMID:26742060

Whole body synthesis rates of DHA from α-linolenic acid are greater than brain DHA accretion and uptake rates in adult rats.

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Domenichiello, Anthony F; Chen, Chuck T; Trepanier, Marc-Olivier; Stavro, P Mark; Bazinet, Richard P

2014-01-01

Docosahexaenoic acid (DHA) is important for brain function, however, the exact amount required for the brain is not agreed upon. While it is believed that the synthesis rate of DHA from α-linolenic acid (ALA) is low, how this synthesis rate compares with the amount of DHA required to maintain brain DHA levels is unknown. The objective of this work was to assess whether DHA synthesis from ALA is sufficient for the brain. To test this, rats consumed a diet low in n-3 PUFAs, or a diet containing ALA or DHA for 15 weeks. Over the 15 weeks, whole body and brain DHA accretion was measured, while at the end of the study, whole body DHA synthesis rates, brain gene expression, and DHA uptake rates were measured. Despite large differences in body DHA accretion, there was no difference in brain DHA accretion between rats fed ALA and DHA. In rats fed ALA, DHA synthesis and accretion was 100-fold higher than brain DHA accretion of rats fed DHA. Also, ALA-fed rats synthesized approximately 3-fold more DHA than the DHA uptake rate into the brain. This work indicates that DHA synthesis from ALA may be sufficient to supply the brain.

DHA effects in brain development and function

DEFF Research Database (Denmark)

Lauritzen, Lotte; Brambilla, Paola; Mazzocchi, Allesandra

2016-01-01

the endogenous formation of DHA seems to be relatively low, DHA intake may contribute to optimal conditions for brain development. We performed a narrative review on research on the associations between DHA levels and brain development and function throughout the lifespan. Data from cell and animal studies...... justify the indication of DHA in relation to brain function for neuronal cell growth and differentiation as well as in relation to neuronal signaling. Most data from human studies concern the contribution of DHA to optimal visual acuity development. Accumulating data indicate that DHA may have effects...

DHA-fluorescent probe is sensitive to membrane order and reveals molecular adaptation of DHA in ordered lipid microdomains☆

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Teague, Heather; Ross, Ron; Harris, Mitchel; Mitchell, Drake C.; Shaikh, Saame Raza

2012-01-01

Docosahexaenoic acid (DHA) disrupts the size and order of plasma membrane lipid microdomains in vitro and in vivo. However, it is unknown how the highly disordered structure of DHA mechanistically adapts to increase the order of tightly packed lipid microdomains. Therefore, we studied a novel DHA-Bodipy fluorescent probe to address this issue. We first determined if the DHA-Bodipy probe localized to the plasma membrane of primary B and immortal EL4 cells. Image analysis revealed that DHA-Bodipy localized into the plasma membrane of primary B cells more efficiently than EL4 cells. We then determined if the probe detected changes in plasma membrane order. Quantitative analysis of time-lapse movies established that DHA-Bodipy was sensitive to membrane molecular order. This allowed us to investigate how DHA-Bodipy physically adapted to ordered lipid microdomains. To accomplish this, we employed steady-state and time-resolved fluorescence anisotropy measurements in lipid vesicles of varying composition. Similar to cell culture studies, the probe was highly sensitive to membrane order in lipid vesicles. Moreover, these experiments revealed, relative to controls, that upon incorporation into highly ordered microdomains, DHA-Bodipy underwent an increase in its fluorescence lifetime and molecular order. In addition, the probe displayed a significant reduction in its rotational diffusion compared to controls. Altogether, DHA-Bodipy was highly sensitive to membrane order and revealed for the first time that DHA, despite its flexibility, could become ordered with less rotational motion inside ordered lipid microdomains. Mechanistically, this explains how DHA acyl chains can increase order upon formation of lipid microdomains in vivo. PMID:22841541

Whole body synthesis rates of DHA from α-linolenic acid are greater than brain DHA accretion and uptake rates in adult rats[S

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Domenichiello, Anthony F.; Chen, Chuck T.; Trepanier, Marc-Olivier; Stavro, P. Mark; Bazinet, Richard P.

2014-01-01

Docosahexaenoic acid (DHA) is important for brain function, however, the exact amount required for the brain is not agreed upon. While it is believed that the synthesis rate of DHA from α-linolenic acid (ALA) is low, how this synthesis rate compares with the amount of DHA required to maintain brain DHA levels is unknown. The objective of this work was to assess whether DHA synthesis from ALA is sufficient for the brain. To test this, rats consumed a diet low in n-3 PUFAs, or a diet containing ALA or DHA for 15 weeks. Over the 15 weeks, whole body and brain DHA accretion was measured, while at the end of the study, whole body DHA synthesis rates, brain gene expression, and DHA uptake rates were measured. Despite large differences in body DHA accretion, there was no difference in brain DHA accretion between rats fed ALA and DHA. In rats fed ALA, DHA synthesis and accretion was 100-fold higher than brain DHA accretion of rats fed DHA. Also, ALA-fed rats synthesized approximately 3-fold more DHA than the DHA uptake rate into the brain. This work indicates that DHA synthesis from ALA may be sufficient to supply the brain. PMID:24212299

Dietary docosahexaenoic acid (DHA) as lysophosphatidylcholine, but not as free acid, enriches brain DHA and improves memory in adult mice

OpenAIRE

Sugasini, Dhavamani; Thomas, Riya; Yalagala, Poorna C. R.; Tai, Leon M.; Subbaiah, Papasani V.

2017-01-01

Docosahexaenoic acid (DHA) is uniquely concentrated in the brain, and is essential for its function, but must be mostly acquired from diet. Most of the current supplements of DHA, including fish oil and krill oil, do not significantly increase brain DHA, because they are hydrolyzed to free DHA and are absorbed as triacylglycerol, whereas the transporter at blood brain barrier is specific for phospholipid form of DHA. Here we show that oral administration of DHA to normal adult mice as lysopho...

Crystallographic analysis of 1,2,3-trichloropropane biodegradation by the haloalkane dehalogenase DhaA31.

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Lahoda, Maryna; Mesters, Jeroen R; Stsiapanava, Alena; Chaloupkova, Radka; Kuty, Michal; Damborsky, Jiri; Kuta Smatanova, Ivana

2014-02-01

Haloalkane dehalogenases catalyze the hydrolytic cleavage of carbon-halogen bonds, which is a key step in the aerobic mineralization of many environmental pollutants. One important pollutant is the toxic and anthropogenic compound 1,2,3-trichloropropane (TCP). Rational design was combined with saturation mutagenesis to obtain the haloalkane dehalogenase variant DhaA31, which displays an increased catalytic activity towards TCP. Here, the 1.31 Å resolution crystal structure of substrate-free DhaA31, the 1.26 Å resolution structure of DhaA31 in complex with TCP and the 1.95 Å resolution structure of wild-type DhaA are reported. Crystals of the enzyme-substrate complex were successfully obtained by adding volatile TCP to the reservoir after crystallization at pH 6.5 and room temperature. Comparison of the substrate-free structure with that of the DhaA31 enzyme-substrate complex reveals that the nucleophilic Asp106 changes its conformation from an inactive to an active state during the catalytic cycle. The positions of three chloride ions found inside the active site of the enzyme indicate a possible pathway for halide release from the active site through the main tunnel. Comparison of the DhaA31 variant with wild-type DhaA revealed that the introduced substitutions reduce the volume and the solvent-accessibility of the active-site pocket.

Construction of mutant glucose oxidases with increased dye-mediated dehydrogenase activity.

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Horaguchi, Yohei; Saito, Shoko; Kojima, Katsuhiro; Tsugawa, Wakako; Ferri, Stefano; Sode, Koji

2012-11-02

Mutagenesis studies on glucose oxidases (GOxs) were conducted to construct GOxs with reduced oxidase activity and increased dehydrogenase activity. We focused on two representative GOxs, of which crystal structures have already been reported—Penicillium amagasakiense GOx (PDB ID; 1gpe) and Aspergillus niger GOx (PDB ID; 1cf3). We constructed oxygen-interacting structural models for GOxs, and predicted the residues responsible for oxidative half reaction with oxygen on the basis of the crystal structure of cholesterol oxidase as well as on the fact that both enzymes are members of the glucose/methanol/choline (GMC) oxidoreductase family. Rational amino acid substitution resulted in the construction of an engineered GOx with drastically decreased oxidase activity and increased dehydrogenase activity, which was higher than that of the wild-type enzyme. As a result, the dehydrogenase/oxidase ratio of the engineered enzyme was more than 11-fold greater than that of the wild-type enzyme. These results indicate that alteration of the dehydrogenase/oxidase activity ratio of GOxs is possible by introducing a mutation into the putative functional residues responsible for oxidative half reaction with oxygen of these enzymes, resulting in a further increased dehydrogenase activity. This is the first study reporting the alteration of GOx electron acceptor preference from oxygen to an artificial electron acceptor.

Construction of Mutant Glucose Oxidases with Increased Dye-Mediated Dehydrogenase Activity

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Horaguchi, Yohei; Saito, Shoko; Kojima, Katsuhiro; Tsugawa, Wakako; Ferri, Stefano; Sode, Koji

2012-01-01

Mutagenesis studies on glucose oxidases (GOxs) were conducted to construct GOxs with reduced oxidase activity and increased dehydrogenase activity. We focused on two representative GOxs, of which crystal structures have already been reported—Penicillium amagasakiense GOx (PDB ID; 1gpe) and Aspergillus niger GOx (PDB ID; 1cf3). We constructed oxygen-interacting structural models for GOxs, and predicted the residues responsible for oxidative half reaction with oxygen on the basis of the crystal structure of cholesterol oxidase as well as on the fact that both enzymes are members of the glucose/methanol/choline (GMC) oxidoreductase family. Rational amino acid substitution resulted in the construction of an engineered GOx with drastically decreased oxidase activity and increased dehydrogenase activity, which was higher than that of the wild-type enzyme. As a result, the dehydrogenase/oxidase ratio of the engineered enzyme was more than 11-fold greater than that of the wild-type enzyme. These results indicate that alteration of the dehydrogenase/oxidase activity ratio of GOxs is possible by introducing a mutation into the putative functional residues responsible for oxidative half reaction with oxygen of these enzymes, resulting in a further increased dehydrogenase activity. This is the first study reporting the alteration of GOx electron acceptor preference from oxygen to an artificial electron acceptor. PMID:23203056

The effect of insulin, TNFα and DHA on the proliferation, differentiation and lipolysis of preadipocytes isolated from large yellow croaker (Pseudosciaena Crocea R.).

Science.gov (United States)

Wang, Xinxia; Huang, Ming; Wang, Yizhen

2012-01-01

Fish final product can be affected by excessive lipid accumulation. Therefore, it is important to develop strategies to control obesity in cultivated fish to strengthen the sustainability of the aquaculture industry. As in mammals, the development of adiposity in fish depends on hormonal, cytokine and dietary factors. In this study, we investigated the proliferation and differentiation of preadipocytes isolated from the large yellow croaker and examined the effects of critical factors such as insulin, TNFα and DHA on the proliferation, differentiation and lipolysis of adipocytes. Preadipocytes were isolated by collagenase digestion, after which their proliferation was evaluated. The differentiation process was optimized by assaying glycerol-3-phosphate dehydrogenase (GPDH) activity. Oil red O staining and electron microscopy were performed to visualize the accumulated triacylglycerol. Gene transcript levels were measured using SYBR green quantitative real-time PCR. Insulin promoted preadipocytes proliferation, stimulated cell differentiation and decreased lipolysis of mature adipocytes. TNFα and DHA inhibited cell proliferation and differentiation. While TNFα stimulated mature adipocyte lipolysis, DHA showed no lipolytic effect on adipocytes. The expressions of adipose triglyceride lipase (ATGL), fatty acid synthase (FAS), lipoprotein lipase (LPL) and peroxisome proliferator-activated receptor α, γ (PPARα, PPARγ) were quantified during preadipocytes differentiation and adipocytes lipolysis to partly explain the regulation mechanisms. In summary, the results of this study indicated that although preadipocytes proliferation and the differentiation process in large yellow croaker are similar to these processes in mammals, the effects of critical factors such as insulin, TNFα and DHA on fish adipocytes development are not exactly the same. Our findings fill in the gaps in the basic data regarding the effects of critical factors on adiposity development in fish

Construction of Mutant Glucose Oxidases with Increased Dye-Mediated Dehydrogenase Activity

Directory of Open Access Journals (Sweden)

Koji Sode

2012-11-01

Full Text Available Mutagenesis studies on glucose oxidases (GOxs were conducted to construct GOxs with reduced oxidase activity and increased dehydrogenase activity. We focused on two representative GOxs, of which crystal structures have already been reported—Penicillium amagasakiense GOx (PDB ID; 1gpe and Aspergillus niger GOx (PDB ID; 1cf3. We constructed oxygen-interacting structural models for GOxs, and predicted the residues responsible for oxidative half reaction with oxygen on the basis of the crystal structure of cholesterol oxidase as well as on the fact that both enzymes are members of the glucose/methanol/choline (GMC oxidoreductase family. Rational amino acid substitution resulted in the construction of an engineered GOx with drastically decreased oxidase activity and increased dehydrogenase activity, which was higher than that of the wild-type enzyme. As a result, the dehydrogenase/oxidase ratio of the engineered enzyme was more than 11-fold greater than that of the wild-type enzyme. These results indicate that alteration of the dehydrogenase/oxidase activity ratio of GOxs is possible by introducing a mutation into the putative functional residues responsible for oxidative half reaction with oxygen of these enzymes, resulting in a further increased dehydrogenase activity. This is the first study reporting the alteration of GOx electron acceptor preference from oxygen to an artificial electron acceptor.

9-Hydroxyprostaglandin dehydrogenase activity in the adult rat kidney. Regional distribution and sub-fractionation.

Science.gov (United States)

Asciak, C P; Domazet, Z

1975-02-20

1. Catabolism of prostaglandin F2alpha in the adult rat kidney takes place by the following sequence of enzymatic steps: (1) 15-hydroxyprostaglandin dehydrogenase; (2) prostaglandin delta13-reductase; and (3) 9-hydroxyprostaglandin dehydrogenase. 2. 9-Hydroxyprostaglandin dehydrogenase activity was highest in the cortex with lesser amounts in the medulla and negligible activity detected in the papilla. A similar distribution was observed for 15-hydroxyprostaglandin dehydrogenase and prostaglandin delta13-reductase. 3. Most of the 9-hydroxyprostaglandin dehydrogenase activity in the homogenate was found in the high-speed supernatant as also observed for 15-hydroxyprostaglandin dehydrogenase and prostaglandin delta13-reductase. 4. These observations indicate that the rat kidney contains an abundance of prostaglandin-catabolising enzymes which favour formation of metabolites of the E-type.

Crystals of DhaA mutants from Rhodococcus rhodochrous NCIMB 13064 diffracted to ultrahigh resolution: crystallization and preliminary diffraction analysis.

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Stsiapanava, Alena; Koudelakova, Tana; Lapkouski, Mikalai; Pavlova, Martina; Damborsky, Jiri; Smatanova, Ivana Kuta

2008-02-01

The enzyme DhaA from Rhodococcus rhodochrous NCIMB 13064 belongs to the haloalkane dehalogenases, which catalyze the hydrolysis of haloalkanes to the corresponding alcohols. The haloalkane dehalogenase DhaA and its variants can be used to detoxify the industrial pollutant 1,2,3-trichloropropane (TCP). Three mutants named DhaA04, DhaA14 and DhaA15 were constructed in order to study the importance of tunnels connecting the buried active site with the surrounding solvent to the enzymatic activity. All protein mutants were crystallized using the sitting-drop vapour-diffusion method. The crystals of DhaA04 belonged to the orthorhombic space group P2(1)2(1)2(1), while the crystals of the other two mutants DhaA14 and DhaA15 belonged to the triclinic space group P1. Native data sets were collected for the DhaA04, DhaA14 and DhaA15 mutants at beamline X11 of EMBL, DESY, Hamburg to the high resolutions of 1.30, 0.95 and 1.15 A, respectively.

Reevaluation of the DHA requirement for the premature infant.

Science.gov (United States)

Lapillonne, Alexandre; Jensen, Craig L

2009-01-01

The long-chain polyunsaturated fatty acid (LC-PUFA) intake in preterm infants is crucial for normal central nervous system development and has the potential for long-lasting effects that extend beyond the period of dietary insufficiency. While much attention has focused on improving their nutritional intake, many premature infants do not receive an adequate DHA supply. We demonstrate that enterally fed premature infants exhibit daily DHA deficit of 20mg/kg.d, representing 44% of the DHA that should have been accumulated. Furthermore, the DHA content of human milk and current preterm formulas cannot compensate for an early DHA deficit which may occur during the first month of life. We recommend breast-feeding, which supplies preformed LC-PUFA, as the preferred method of feeding for preterm infants. However, to fulfill the specific DHA requirement of these infants, we recommend increasing the DHA content of human milk either by providing the mothers with a DHA supplement or by adding DHA directly to the milk. Increasing the DHA content above 1% total fatty acids appears to be safe and may enhance neurological development particularly that of infants with a birth weight below 1250 g. We estimate that human milk and preterm formula should contain approximately 1.5% of fatty acid as DHA to prevent the appearance of a DHA deficit and to compensate for the early DHA deficit.

Soil dehydrogenase activity of natural macro aggregates in a toposequence of forest soil

Directory of Open Access Journals (Sweden)

Maira Kussainova

2013-01-01

Full Text Available The main objective of this study was to determine changes in soil dehydrogenase activity in natural macro aggregates development along a slope in forest soils. This study was carried out in Kocadag, Samsun, Turkey. Four landscape positions i.e., summit, shoulder backslope and footslope, were selected. For each landseape position, soil macro aggregates were separated into six aggregate size classes using a dry sieving method and then dehydrogenase activity was analyzed. In this research, topography influenced the macroaggregate size and dehydrogenase activity within the aggregates. At all landscape positions, the contents of macro aggregates (especially > 6.3 mm and 2.00–4.75 mm in all soil samples were higher than other macro aggregate contents. In footslope position, the soils had generally the higher dehydrogenase activity than the other positions at all landscape positions. In all positions, except for shoulder, dehydrogenase activity was greater macro aggregates of <1 mm than in the other macro aggregate size.

Crystals of DhaA mutants from Rhodococcus rhodochrous NCIMB 13064 diffracted to ultrahigh resolution: crystallization and preliminary diffraction analysis

International Nuclear Information System (INIS)

Stsiapanava, Alena; Koudelakova, Tana; Lapkouski, Mikalai; Pavlova, Martina; Damborsky, Jiri; Kuta Smatanova, Ivana

2008-01-01

Three mutants of the haloalkane dehalogenase DhaA derived from R. rhodochrous NCIMB 13064 were crystallized and diffracted to ultrahigh resolution. The enzyme DhaA from Rhodococcus rhodochrous NCIMB 13064 belongs to the haloalkane dehalogenases, which catalyze the hydrolysis of haloalkanes to the corresponding alcohols. The haloalkane dehalogenase DhaA and its variants can be used to detoxify the industrial pollutant 1,2,3-trichloropropane (TCP). Three mutants named DhaA04, DhaA14 and DhaA15 were constructed in order to study the importance of tunnels connecting the buried active site with the surrounding solvent to the enzymatic activity. All protein mutants were crystallized using the sitting-drop vapour-diffusion method. The crystals of DhaA04 belonged to the orthorhombic space group P2 1 2 1 2 1 , while the crystals of the other two mutants DhaA14 and DhaA15 belonged to the triclinic space group P1. Native data sets were collected for the DhaA04, DhaA14 and DhaA15 mutants at beamline X11 of EMBL, DESY, Hamburg to the high resolutions of 1.30, 0.95 and 1.15 Å, respectively

Aminotransferase and glutamate dehydrogenase activities in lactobacilli and streptococci

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Guillermo Hugo Peralta

Full Text Available ABSTRACT Aminotransferases and glutamate dehydrogenase are two main types of enzymes involved in the initial steps of amino acid catabolism, which plays a key role in the cheese flavor development. In the present work, glutamate dehydrogenase and aminotransferase activities were screened in twenty one strains of lactic acid bacteria of dairy interest, either cheese-isolated or commercial starters, including fifteen mesophilic lactobacilli, four thermophilic lactobacilli, and two streptococci. The strains of Streptococcus thermophilus showed the highest glutamate dehydrogenase activity, which was significantly elevated compared with the lactobacilli. Aspartate aminotransferase prevailed in most strains tested, while the levels and specificity of other aminotransferases were highly strain- and species-dependent. The knowledge of enzymatic profiles of these starter and cheese-isolated cultures is helpful in proposing appropriate combinations of strains for improved or increased cheese flavor.

A Mini-Review on the Effect of Docosahexaenoic Acid (DHA on Cerulein-Induced and Hypertriglyceridemic Acute Pancreatitis

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Yoo Kyung Jeong

2017-10-01

Full Text Available Acute pancreatitis refers to the sudden inflammation of the pancreas. It is associated with premature activation and release of digestive enzymes into the pancreatic interstitium and systemic circulation, resulting in pancreatic tissue autodigestion and multiple organ dysfunction, as well as with increased cytokine production, ultimately leading to deleterious local and systemic effects. Although mechanisms involved in pathogenesis of acute pancreatitis have not been completely elucidated, oxidative stress is regarded as a major risk factor. In human acute pancreatitis, lipid peroxide levels in pancreatic tissues increase. Docosahexaenoic acid (DHA, an omega-3 polyunsaturated fatty acid (C22:6n-3, exerts anti-inflammatory and antioxidant effects on various cells. Previous studies have shown that DHA activates peroxisome proliferator-activated receptor-γ and induces catalase, which inhibits oxidative stress-mediated inflammatory signaling required for cytokine expression in experimental acute pancreatitis using cerulein. Cerulein, a cholecystokinin analog, induces intra-acinar activation of trypsinogen in the pancreas, which results in human acute pancreatitis-like symptoms. Therefore, DHA supplementation may be beneficial for preventing or inhibiting acute pancreatitis development. Since DHA reduces serum triglyceride levels, addition of DHA to lipid-lowering drugs like statins has been investigated to reduce hypertriglyceridemic acute pancreatitis. However, high DHA concentrations increase cytosolic Ca2+, which activates protein kinase C and may induce hyperlipidemic acute pancreatitis. In this review, effect of DHA on cerulein-induced and hypertriglyceridemic acute pancreatitis has been discussed. The relation of high concentration of DHA to hyperlipidemic acute pancreatitis has been included.

Docosahexaenoic acid (DHA) accretion in the placenta but not the fetus is matched by plasma unesterified DHA uptake rates in pregnant Long Evans rats.

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Metherel, Adam H; Kitson, Alex P; Domenichiello, Anthony F; Lacombe, R J Scott; Hopperton, Kathryn E; Trépanier, Marc-Olivier; Alashmali, Shoug M; Lin, Lin; Bazinet, Richard P

2017-10-01

Maternal delivery of docosahexaenoic acid (DHA, 22:6n-3) to the developing fetus via the placenta is required for fetal neurodevelopment, and is the only mechanism by which DHA can be accreted in the fetus. The aim of the current study was to utilize a balance model of DHA accretion combined with kinetic measures of serum unesterified DHA uptake to better understand the mechanism by which maternal DHA is delivered to the fetus via the placenta. Female rats maintained on a 2% α-linolenic acid diet free of DHA for 56 days were mated, and for balance analysis, sacrificed at 18 days of pregnancy, and fetus, placenta and maternal carcass fatty acid concentration were determined. For tissue DHA uptake, pregnant dams (14-18 days) were infused for 5 min with radiolabeled 14 C-DHA and kinetic modeling was used to determine fetal and placental serum unesterified DHA uptake rates. DHA accretion rates in the fetus were determined to be 38 ± 2 nmol/d/g, 859 ± 100 nmol/d/litter and 74 ± 3 nmol/d/pup, which are all higher (P  0.05) in placental DHA accretion rates versus serum unesterified DHA uptake rates were observed as values varied only 6-35% between studies. No differences in placental accretion and uptake rates suggests that serum unesterified DHA is a significant pool for the maternal-placental transfer of DHA, and lower fetal DHA uptake compared to accretion supports remodeling of placental DHA for delivery to the fetus. Copyright © 2017 Elsevier Ltd. All rights reserved.

Effect of cerulenin on fatty acid composition and gene expression pattern of DHA-producing strain Colwellia psychrerythraea strain 34H.

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Wan, Xia; Peng, Yun-Feng; Zhou, Xue-Rong; Gong, Yang-Min; Huang, Feng-Hong; Moncalián, Gabriel

2016-02-06

Colwellia psychrerythraea 34H is a psychrophilic bacterium able to produce docosahexaenoic acid (DHA). Polyketide synthase pathway is assumed to be responsible for DHA production in marine bacteria. Five pfa genes from strain 34H were confirmed to be responsible for DHA formation by heterogeneous expression in Escherichia coli. The complexity of fatty acid profile of this strain was revealed by GC and GC-MS. Treatment of cells with cerulenin resulted in significantly reduced level of C16 monounsaturated fatty acid (C16:1(Δ9t), C16:1(Δ7)). In contrast, the amount of saturated fatty acids (C10:0, C12:0, C14:0), hydroxyl fatty acids (3-OH C10:0 and 3-OH C12:0), as well as C20:4ω3, C20:5ω3 and C22:6ω3 were increased. RNA sequencing (RNA-Seq) revealed the altered gene expression pattern when C. psychrerythraea cells were treated with cerulenin. Genes involved in polyketide synthase pathway and fatty acid biosynthesis pathway were not obviously affected by cerulenin treatment. In contrast, several genes involved in fatty acid degradation or β-oxidation pathway were dramatically reduced at the transcriptional level. Genes responsible for DHA formation in C. psychrerythraea was first cloned and characterized. We revealed the complexity of fatty acid profile in this DHA-producing strain. Cerulenin could substantially change the fatty acid composition by affecting the fatty acid degradation at transcriptional level. Acyl-CoA dehydrogenase gene family involved in the first step of β-oxidation pathway may be important to the selectivity of degraded fatty acids. In addition, inhibition of FabB protein by cerulenin may lead to the accumulation of malonyl-CoA, which is the substrate for DHA formation.

Maternal DHA levels and toddler free-play attention.

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Kannass, Kathleen N; Colombo, John; Carlson, Susan E

2009-01-01

We investigated the relationship between maternal docosahexaenoic acid (DHA) levels at birth and toddler free-play attention in the second year. Toddler free-play attention was assessed at 12 and 18 months, and maternal erythrocyte (red-blood cell; RBC) phospholipid DHA (percentage of total fatty acids) was measured from mothers at delivery. Overall, higher maternal DHA status at birth was associated with enhanced attentional functioning during the second year. Toddlers whose mothers had high DHA at birth exhibited more total looking and fewer episodes of inattention during free-play than did toddlers whose mothers had low DHA at birth. Analyses also provided further information on changes in attention during toddlerhood. These findings are consistent with evidence suggesting a link between DHA and cognitive development in infancy and early childhood.

The Relationship of Docosahexaenoic Acid (DHA) with Learning and Behavior in Healthy Children: A Review

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Kuratko, Connye N.; Barrett, Erin Cernkovich; Nelson, Edward B.; Norman, Salem

2013-01-01

Childhood is a period of brain growth and maturation. The long chain omega-3 fatty acid, docosahexaenoic acid (DHA), is a major lipid in the brain recognized as essential for normal brain function. In animals, low brain DHA results in impaired learning and behavior. In infants, DHA is important for optimal visual and cognitive development. The usual intake of DHA among toddlers and children is low and some studies show improvements in cognition and behavior as the result of supplementation with polyunsaturated fatty acids including DHA. The purpose of this review was to identify and evaluate current knowledge regarding the relationship of DHA with measures of learning and behavior in healthy school-age children. A systematic search of the literature identified 15 relevant publications for review. The search found studies which were diverse in purpose and design and without consistent conclusions regarding the treatment effect of DHA intake or biomarker status on specific cognitive tests. However, studies of brain activity reported benefits of DHA supplementation and over half of the studies reported a favorable role for DHA or long chain omega-3 fatty acids in at least one area of cognition or behavior. Studies also suggested an important role for DHA in school performance. PMID:23877090

The Relationship of Docosahexaenoic Acid (DHA with Learning and Behavior in Healthy Children: A Review

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Norman Salem

2013-07-01

Full Text Available Childhood is a period of brain growth and maturation. The long chain omega-3 fatty acid, docosahexaenoic acid (DHA, is a major lipid in the brain recognized as essential for normal brain function. In animals, low brain DHA results in impaired learning and behavior. In infants, DHA is important for optimal visual and cognitive development. The usual intake of DHA among toddlers and children is low and some studies show improvements in cognition and behavior as the result of supplementation with polyunsaturated fatty acids including DHA. The purpose of this review was to identify and evaluate current knowledge regarding the relationship of DHA with measures of learning and behavior in healthy school-age children. A systematic search of the literature identified 15 relevant publications for review. The search found studies which were diverse in purpose and design and without consistent conclusions regarding the treatment effect of DHA intake or biomarker status on specific cognitive tests. However, studies of brain activity reported benefits of DHA supplementation and over half of the studies reported a favorable role for DHA or long chain omega-3 fatty acids in at least one area of cognition or behavior. Studies also suggested an important role for DHA in school performance.

Effects of sh-reagents on rat hepatic aldehyde dehydrogenase activity

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Konoplitskaya, K.L.; Kuz' mina, G.I.; Grigor' yeva, M.V.; Poznyakova, T.N.

The liver serves as the primary organ for the oxidation of ingested ethanol via a pathway involving alcohol- and aldehyde dehydrogenase. In view of the problem of alcoholism, three enzymes are of particular interest in understanding the biochemical mechanism that may be involved in alcohol addiction and in the formulation of therapeutic approaches. While alcohol dehydrogenase has been studied in considerable detail, current attention is centered on aldehyde dehydrogenase. A comparative analysis of the effects of a series of SH-active reagents - tetraethylthiuram disulfide (TETD), 5,5-dithiobisnitrobenzoic acid (DTNB), p-chloromercurybenzoate (PCMB), and N-ethylmaleimide (NEM) - were tested for their effects on the activity of aldehyde dehydrogenase of the hepatic mitochondrial (isozymes I and II) and microsomal (isozyme II) fractions of outbred albino rats. DTNB was found to be inhibited by 100 and 50% mitochondrial isozymes I and II, respectively, and by 20%, the microsomal enzyme under the conditions employed. DTNB and NEM inhibited by 30 and 50% isozymes I and II of the mitochondria, but had no effect on the microsomal isozyme. 24 references, 3 figures.

Effect of Oral Docosahexaenoic Acid (DHA) Supplementation on DHA Levels and Omega-3 Index in Red Blood Cell Membranes of Breast Cancer Patients.

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Molfino, Alessio; Amabile, Maria I; Mazzucco, Sara; Biolo, Gianni; Farcomeni, Alessio; Ramaccini, Cesarina; Antonaroli, Simonetta; Monti, Massimo; Muscaritoli, Maurizio

2017-01-01

Rationale: Docosahexaenoic acid (DHA) in cell membrane may influence breast cancer (BC) patients' prognosis, affecting tumor cells sensitivity to chemo- and radio-therapy and likely modulating inflammation. The possibility of identifying BC patients presenting with low DHA levels and/or low ability of DHA incorporation into cell membrane might help to treat this condition. Methods: We enrolled BC patients and healthy controls, recording their seafood dietary intake. DHA in form of algal oil was administered for 10 consecutive days (2 g/day). Blood samples were collected at baseline (T0) and after 10 days of supplementation (T1) to assess DHA, omega-3 index, as the sum of DHA + eicosapentaenoic acid (EPA), in red blood cells (RBC) membranes and plasma tumor necrosis factor-alpha and interleukin-6 levels. Pre- and post-treatment fatty acid profiles were obtained by gas-chromatography. Parametric and non-parametric tests were performed, as appropriate, and P -value DHA and omega-3 index increased from T0 to T1 in the 3 groups of BC patients and in controls ( P DHA incorporation between each group of BC patients and between patients and controls, except for M group, which incorporated higher DHA levels with respect to controls (β = 0.42; P = 0.03). No association was documented between cytokines levels and DHA and omega-3 index at baseline and after DHA supplementation. Independent of the presence of BC, women considered as "good seafood consumers" showed at baseline DHA and omega-3 index higher with respect to "low seafood consumers" ( P = 0.04; P = 0.007, respectively). After supplementation, the increase in DHA levels was greater in "low seafood consumers" with respect to "good seafood consumers" ( P DHA supplementation was associated with increased DHA levels and omega-3 index in RBC membranes of BC cancer patients, independent of the type of BC presentation, and in controls. BRCA1/2 mutation, as well as low seafood consuming habits in both BC patients and healthy

Docosahexaenoic acid (DHA, essentiality and requirements: why and how to provide supplementation

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Nieto, Susana

2006-06-01

Full Text Available Lipids comprize from 50-60% of the structural matter of the brain and docosahexaenoic acid (C22:6, DHA is the most  important omega-3 long-chain polyunsaturated fatty acid in the brain phospholipids comprizing 25% of the total fatty acids of the grey matter. The majority of the DHA present in the human brain is incorporated during the brain growth spurt which starts at week 26 of gestation and imposes a high demand for the fatty acid until about 2 years of age. DHA is required during brain development when neuronal and glial differentiation and migration, and active myelination and synaptogenesis take place. The fatty acid must be incorporated into the brain lipids as preformed DHA because less than 5% of its precursor (alpha linolenic acid, LNA is converted to DHA. The human foetus has a limited ability to synthesize DHA from LNA, and therefore it must be largely supplied from maternal sources. Maternal DHA available for foetal nutrition can be provided from three main sources: adipose tissue, which is the main reservoir for the fatty acid; through biosynthesis from the precursor LNA, which occurs mainly in the liver; and as preformed DHA from dietary sources. In the postnatal period DHA is provided by the mother to the newborn through milk secretion. Western nutrition provides low LNA and DHA and Expert Nutrition Committees suggest that mothers should receive DHA supplementation during pregnancy and lactation. At present DHA supplementation can be provided from different sources: as purified free DHA, as an ethyl ester derivative, extracted from single-cell algae oils, from egg yolk phospholipids, or in the form of sn-2 DHA monoacylglycerol. In this review we revise and discuss the evidence of DHA requirements for the newborn, the need for maternal supplementation during pregnancy and nursing, and the alternatives at present for providing DHA supplementation.Los lípidos comprenden entre el 50-60% de la estructura del cerebro, y el �

Effects of different dietary DHA:EPA ratios on gonadal steroidogenesis in the marine teleost, tongue sole (Cynoglossus semilaevis).

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Xu, Houguo; Cao, Lin; Wei, Yuliang; Zhang, Yuanqin; Liang, Mengqing

2017-08-01

The present study was conducted to investigate the effects of dietary DHA and EPA on gonadal steroidogenesis in mature females and males, with a feeding trial on tongue sole, a typical marine teleost with sexual dimorphism. Three experimental diets differing basically in DHA:EPA ratio, that is, 0·68 (diet D:E-0·68), 1·09 (D:E-1·09) and 2·05 (D:E-2·05), were randomly assigned to nine tanks of 3-year-old tongue sole (ten females and fifteen males in each tank). The feeding trail lasted for 90 d before and during the spawning season. Fish were reared in a flowing seawater system and fed to apparent satiation twice daily. Compared with diet D:E-0·68, diet D:E-1·09 significantly enhanced the oestradiol production in females, whereas diet D:E-2·05 significantly enhanced the testosterone production in males. In ovaries, diet D:E-1·09 induced highest mRNA expression of follicle-stimulating hormone receptor (FSHR), steroidogenic acute regulatory protein, 17α-hydroxylase (P450c17) and 3β-hydroxysteroid dehydrogenase (3β-HSD). In testes, diet 2·05 resulted in highest mRNA expression of FSHR, cholesterol side-chain cleavage enzyme, P450c17 and 3β-HSD. Fatty acid profiles in fish tissues reflected closely those of diets. Female fish had more gonadal EPA content but less DHA content than male fish, whereas there was a reverse observation in liver. In conclusion, the dietary DHA:EPA ratio, possibly combined with the dietary EPA:arachidonic acid ratio, differentially regulated sex steroid hormone synthesis in mature female and male tongue soles. Females seemed to require more EPA but less DHA for the gonadal steroidogenesis than males. The results are beneficial to sex-specific nutritive strategies in domestic teleost.

Mechanistic study of manganese-substituted glycerol dehydrogenase using a kinetic and thermodynamic analysis.

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Fang, Baishan; Niu, Jin; Ren, Hong; Guo, Yingxia; Wang, Shizhen

2014-01-01

Mechanistic insights regarding the activity enhancement of dehydrogenase by metal ion substitution were investigated by a simple method using a kinetic and thermodynamic analysis. By profiling the binding energy of both the substrate and product, the metal ion's role in catalysis enhancement was revealed. Glycerol dehydrogenase (GDH) from Klebsiella pneumoniae sp., which demonstrated an improvement in activity by the substitution of a zinc ion with a manganese ion, was used as a model for the mechanistic study of metal ion substitution. A kinetic model based on an ordered Bi-Bi mechanism was proposed considering the noncompetitive product inhibition of dihydroxyacetone (DHA) and the competitive product inhibition of NADH. By obtaining preliminary kinetic parameters of substrate and product inhibition, the number of estimated parameters was reduced from 10 to 4 for a nonlinear regression-based kinetic parameter estimation. The simulated values of time-concentration curves fit the experimental values well, with an average relative error of 11.5% and 12.7% for Mn-GDH and GDH, respectively. A comparison of the binding energy of enzyme ternary complex for Mn-GDH and GDH derived from kinetic parameters indicated that metal ion substitution accelerated the release of dioxyacetone. The metal ion's role in catalysis enhancement was explicated.

Mechanistic study of manganese-substituted glycerol dehydrogenase using a kinetic and thermodynamic analysis.

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Baishan Fang

Full Text Available Mechanistic insights regarding the activity enhancement of dehydrogenase by metal ion substitution were investigated by a simple method using a kinetic and thermodynamic analysis. By profiling the binding energy of both the substrate and product, the metal ion's role in catalysis enhancement was revealed. Glycerol dehydrogenase (GDH from Klebsiella pneumoniae sp., which demonstrated an improvement in activity by the substitution of a zinc ion with a manganese ion, was used as a model for the mechanistic study of metal ion substitution. A kinetic model based on an ordered Bi-Bi mechanism was proposed considering the noncompetitive product inhibition of dihydroxyacetone (DHA and the competitive product inhibition of NADH. By obtaining preliminary kinetic parameters of substrate and product inhibition, the number of estimated parameters was reduced from 10 to 4 for a nonlinear regression-based kinetic parameter estimation. The simulated values of time-concentration curves fit the experimental values well, with an average relative error of 11.5% and 12.7% for Mn-GDH and GDH, respectively. A comparison of the binding energy of enzyme ternary complex for Mn-GDH and GDH derived from kinetic parameters indicated that metal ion substitution accelerated the release of dioxyacetone. The metal ion's role in catalysis enhancement was explicated.

Exogenous modification of platelet membranes with the omega-3 fatty acids EPA and DHA reduces platelet procoagulant activity and thrombus formation.

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Larson, Mark K; Tormoen, Garth W; Weaver, Lucinda J; Luepke, Kristen J; Patel, Ishan A; Hjelmen, Carl E; Ensz, Nicole M; McComas, Leah S; McCarty, Owen J T

2013-02-01

Several studies have implicated the omega-3 fatty acids eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) in inhibition of normal platelet function, suggesting a role for platelets in EPA- and DHA-mediated cardioprotection. However, it is unclear whether the cardioprotective mechanisms arise from alterations to platelet-platelet, platelet-matrix, or platelet-coagulation factor interactions. Our previous results led us to hypothesize that EPA and DHA alter the ability of platelets to catalyze the generation of thrombin. We tested this hypothesis by exogenously modifying platelet membranes with EPA and DHA, which resulted in compositional changes analogous to increased dietary EPA and DHA intake. Platelets treated with EPA and DHA showed reductions in the rate of thrombin generation and exposure of platelet phosphatidylserine. In addition, treatment of platelets with EPA and DHA decreased thrombus formation and altered the processing of thrombin precursor proteins. Furthermore, treatment of whole blood with EPA and DHA resulted in increased occlusion time and a sharply reduced accumulation of fibrin under flow conditions. These results demonstrate that EPA and DHA inhibit, but do not eliminate, the ability of platelets to catalyze thrombin generation in vitro. The ability of EPA and DHA to reduce the procoagulant function of platelets provides a possible mechanism behind the cardioprotective phenotype in individuals consuming high levels of EPA and DHA.

Links between root carbohydrates and seasonal pattern of soil microbial activity of diverse european populations of Pinus sylvestris grown in a provenance plantation

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Barbara Kaliszewska-Rokicka

2011-01-01

Full Text Available Activity of soil dehydrogenase (DHA was measured in the mineral soil in a forest stand of 15 to 16-year-old Scots pine (Pinus sylvestris L. from geographically diverse populations, as an indicator of biological activity of soil microorganisms, in a provenance experiment in Poland. The pine populations originated from six European countries (Sweden, Russia, Latvia, Poland, Germany, France and differed widely in aboveground biomass and productivity. Soil DHA during two growing seasons showed pronounced seasonal variability, which was significantly related to the fine root concentration of nonstructural carbohydrates. Higher DHA was found in soil under canopies of the central and southern European populations than in those from more northern parts of the Scots pine range. Significant positive correlation between soil DHA and aboveground tree biomass suggest that these patterns most likely resulted from differences in carbon dynamics and productivity among populations.

Docosahexaenoic acid (DHA), a fundamental fatty acid for the brain: New dietary sources.

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Echeverría, Francisca; Valenzuela, Rodrigo; Catalina Hernandez-Rodas, María; Valenzuela, Alfonso

2017-09-01

Docosahexaenoic acid (C22: 6n-3, DHA) is a long-chain polyunsaturated fatty acid of marine origin fundamental for the formation and function of the nervous system, particularly the brain and the retina of humans. It has been proposed a remarkable role of DHA during human evolution, mainly on the growth and development of the brain. Currently, DHA is considered a critical nutrient during pregnancy and breastfeeding due their active participation in the development of the nervous system in early life. DHA and specifically one of its derivatives known as neuroprotectin D-1 (NPD-1), has neuroprotective properties against brain aging, neurodegenerative diseases and injury caused after brain ischemia-reperfusion episodes. This paper discusses the importance of DHA in the human brain given its relevance in the development of the tissue and as neuroprotective agent. It is also included a critical view about the ways to supply this noble fatty acid to the population. Copyright © 2017 Elsevier Ltd. All rights reserved.

The Diagnostic Significance of Serum Alcohol Dehydrogenase Isoenzymes and Aldehyde Dehydrogenase Activity in Urinary Bladder Cancer Patients.

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Orywal, Karolina; Jelski, Wojciech; Werel, Tadeusz; Szmitkowski, Maciej

2017-07-01

The aim of this study was to investigate a potential role of alcohol dehydrogenase and aldehyde dehydrogenase as tumor markers for urinary bladder cancer. Serum samples were obtained from 41 patients with bladder cancer and 52 healthy individuals. Class III and IV of ADH and total ADH activity were measured by the photometric method. For measurement of class I and II ADH and ALDH activity, the fluorometric method was employed. Significantly higher total activity of ADH was found in sera of both, low-grade and high-grade bladder cancer patients. The diagnostic sensitivity for total ADH activity was 81.5%, specificity 98.1%, positive (PPV) and negative (NPV) predictive values were 97.4% and 92.3% respectively. Area under ROC curve for total ADH activity was 0.848. A potential role of total ADH activity as a marker for bladder cancer, is herein proposed. Copyright© 2017, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.

Effect of Oral Docosahexaenoic Acid (DHA Supplementation on DHA Levels and Omega-3 Index in Red Blood Cell Membranes of Breast Cancer Patients

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Alessio Molfino

2017-07-01

Full Text Available Rationale: Docosahexaenoic acid (DHA in cell membrane may influence breast cancer (BC patients' prognosis, affecting tumor cells sensitivity to chemo- and radio-therapy and likely modulating inflammation. The possibility of identifying BC patients presenting with low DHA levels and/or low ability of DHA incorporation into cell membrane might help to treat this condition.Methods: We enrolled BC patients and healthy controls, recording their seafood dietary intake. DHA in form of algal oil was administered for 10 consecutive days (2 g/day. Blood samples were collected at baseline (T0 and after 10 days of supplementation (T1 to assess DHA, omega-3 index, as the sum of DHA + eicosapentaenoic acid (EPA, in red blood cells (RBC membranes and plasma tumor necrosis factor-alpha and interleukin-6 levels. Pre- and post-treatment fatty acid profiles were obtained by gas-chromatography. Parametric and non-parametric tests were performed, as appropriate, and P-value < 0.05 was considered statistically significant.Results: Forty-three women were studied, divided into 4 groups: 11 patients with BRCA1/2 gene mutation (M group, 12 patients with familiar positive history for BC (F group, 10 patients with sporadic BC (S group, and 10 healthy controls (C group. DHA and omega-3 index increased from T0 to T1 in the 3 groups of BC patients and in controls (P < 0.001. No difference was found in DHA incorporation between each group of BC patients and between patients and controls, except for M group, which incorporated higher DHA levels with respect to controls (β = 0.42; P = 0.03. No association was documented between cytokines levels and DHA and omega-3 index at baseline and after DHA supplementation. Independent of the presence of BC, women considered as “good seafood consumers” showed at baseline DHA and omega-3 index higher with respect to “low seafood consumers” (P = 0.04; P = 0.007, respectively. After supplementation, the increase in DHA levels was

Whole body synthesis rates of DHA from α-linolenic acid are greater than brain DHA accretion and uptake rates in adult rats[S

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Domenichiello, Anthony F.; Chen, Chuck T.; Trepanier, Marc-Olivier; Stavro, P. Mark; Bazinet, Richard P.

2014-01-01

Docosahexaenoic acid (DHA) is important for brain function, however, the exact amount required for the brain is not agreed upon. While it is believed that the synthesis rate of DHA from α-linolenic acid (ALA) is low, how this synthesis rate compares with the amount of DHA required to maintain brain DHA levels is unknown. The objective of this work was to assess whether DHA synthesis from ALA is sufficient for the brain. To test this, rats consumed a diet low in n-3 PUFAs, or a diet containing...

Docosahexaenoic acid (DHA) and arachidonic acid (ARA) balance in developmental outcomes.

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Colombo, John; Jill Shaddy, D; Kerling, Elizabeth H; Gustafson, Kathleen M; Carlson, Susan E

2017-06-01

The DHA Intake and Measurement of Neural Development (DIAMOND) trial represents one of only a few studies of the long-term dose-response effects of LCPUFA-supplemented formula feeding during infancy. The trial contrasted the effects of four formulations: 0.00% docosahexaenoic acid (DHA)/0.00% arachidonic acid (ARA), 0.32% DHA/0.64% ARA, 0.64% DHA/0.64% ARA, and 0.96% DHA/0.64% ARA against a control condition (0.00% DHA/0.00% ARA). The results of this trial have been published elsewhere, and show improved cognitive outcomes for infants fed supplemented formulas, but a common finding among many of the outcomes show a reduction of benefit for the highest DHA dose (i.e., 0.96%DHA/0.64% ARA, that is, a DHA: ARA ratio 1.5:1.0). The current paper gathers and summarizes the evidence for the reduction of benefit at this dose, and in an attempt to account for this reduced benefit, presents for the first time data from infants' red blood cell (RBC) assays taken at 4 and 12 months of age. Those assays indicate that blood DHA levels generally rose with increased DHA supplementation, although those levels tended to plateau as the DHA-supplemented level exceeded 0.64%. Perhaps more importantly, ARA levels showed a strong inverted-U function in response to increased DHA supplementation; indeed, infants assigned to the formula with the highest dose of DHA (and highest DHA/ARA ratio) showed a reduction in blood ARA relative to more intermediate DHA doses. This finding raises the possibility that reduced ARA may be responsible for the reduction in benefit on cognitive outcomes seen at this dose. The findings implicate the DHA/ARA balance as an important variable in the contribution of LCPUFAs to cognitive and behavioral development in infancy. Copyright © 2017 Elsevier Ltd. All rights reserved.

DHA in Pregnant and Lactating Women from Coastland, Lakeland, and Inland Areas of China: Results of a DHA Evaluation in Women (DEW) Study

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Li, You; Li, Hong-tian; Trasande, Leonardo; Ge, Hua; Yu, Li-xia; Xu, Gao-sheng; Bai, Man-xi; Liu, Jian-meng

2015-01-01

Few studies have examined docosahexaenoic acid (DHA) in pregnant and lactating women in developing countries like China, where DHA-enriched supplements are increasingly popular. We aimed to assess the DHA status among Chinese pregnant and lactating women residing areas differing in the availability of aquatic products. In total, 1211 women in mid-pregnancy (17 ± 2 weeks), late pregnancy (39 ± 2 weeks), or lactation (42 ± 7 days) were enrolled from Weihai (coastland), Yueyang (lakeland), and Baotou (inland) city, with approximately 135 women in each participant group by region. DHA concentrations were measured using capillary gas chromatography, and are reported as weight percent of total fatty acids. Mean plasma DHA concentrations were higher in coastland (mid-pregnancy 3.19%, late pregnancy 2.54%, lactation 2.24%) and lakeland women (2.45%, 1.95%, 2.26%) than inland women (2.25%, 1.67%, 1.68%) (p values DHA. We conclude that DHA concentrations of Chinese pregnant and lactating women are higher in coastland and lakeland regions than in inland areas. DHA status in the study population appears to be stronger than populations from other countries studied to date. PMID:26506380

Inhibition of dehydrogenase activity in petroleum refinery wastewater bacteria by phenolic compounds

Directory of Open Access Journals (Sweden)

Gideon C. Okpokwasili

2010-04-01

Full Text Available The toxicity of phenol, 2-nitrophenol, 4-nitrophenol, 2,4-dinitrophenol, 2-chlorophenol, 4-chlorophenol, 4-bromophenol and 3,5-dimethylphenol on Pseudomonas, Bacillus and Escherichia species isolated from petroleum refinery wastewater was assessed via inhibition of dehydrogenase enzyme activity. At low concentrations, 2-nitrophenol, 2-chlorophenol, 4-chlorophenol, 4-bromophenol and 3,5-dimethylphenol stimulated dehydrogenase activity and at sufficient concentrations, phenolic compounds inhibited dehydrogenase activities. Generally, phenol is less toxic than substituted phenols. Estimations of the degree of inhibition/stimulation of dehydrogenase activities showed significant dose-dependent responses that are describable by logistic functions. The toxicity thresholds varied significantly (P < 0.05 among the bacterial strains and phenolic compounds. The median inhibitory concentrations (IC50s ranged from 4.118 ± 0.097 mg.L-1 for 4-nitrophenol against Pseudomonas sp. DAF1 to 1407.997 ± 7.091 mg.L-1 for phenol against Bacillus sp. DISK1. This study suggested that the organisms have moderate sensitivity to phenols and have the potential to be used as indicators for assessment of chemical toxicity. They could also be used as catalysts for degradation of phenols in effluents.

A Correlation Study of DHA Dietary Intake and Plasma, Erythrocyte and Breast Milk DHA Concentrations in Lactating Women from Coastland, Lakeland, and Inland Areas of China

Science.gov (United States)

Liu, Meng-Jiao; Li, Hong-Tian; Yu, Li-Xia; Xu, Gao-Sheng; Ge, Hua; Wang, Lin-Lin; Zhang, Ya-Li; Zhou, Yu-Bo; Li, You; Bai, Man-Xi; Liu, Jian-Meng

2016-01-01

We aimed to assess the correlation between docosahexaenoic acid (DHA) dietary intake and the plasma, erythrocyte and breast milk DHA concentrations in lactating women residing in the coastland, lakeland and inland areas of China. A total of 408 healthy lactating women (42 ± 7 days postpartum) were recruited from four hospitals located in Weihai (coastland), Yueyang (lakeland) and Baotou (inland) city. The categories of food containing DHA, the average amount consumed per time and the frequency of consumption in the past month were assessed by a tailored DHA food frequency questionnaire, the DHA Intake Evaluation Tool (DIET). DHA dietary intake (mg/day) was calculated according to the Chinese Food Composition Table (Version 2009). In addition, fasting venous blood (5 mL) and breast milk (10 mL) were collected from lactating women. DHA concentrations in plasma, erythrocyte and breast milk were measured using capillary gas chromatography, and were reported as absolute concentration (μg/mL) and relative concentration (weight percent of total fatty acids, wt. %). Spearman correlation coefficients were used to assess the correlation between intakes of DHA and its concentrations in biological specimens. The study showed that the breast milk, plasma and erythrocyte DHA concentrations were positively correlated with DHA dietary intake; corresponding correlation coefficients were 0.36, 0.36 and 0.24 for relative concentration and 0.33, 0.32, and 0.18 for absolute concentration (p DHA dietary intake varied significantly across areas (p DHA concentrations in breast milk were 0.36% ± 0.23% and 141.49 ± 107.41 μg/mL; the concentrations were significantly lower in inland women than those from coastland and lakeland. We conclude that DHA dietary intake is positively correlated with DHA concentrations in blood and breast milk in Chinese lactating women, suggesting that the tailored DHA food frequency questionnaire, DIET, is a valid tool for the assessment of DHA dietary intake

Safety of docosahexaenoic acid (DHA) administered as DHA ethyl ester in a 9-month toxicity study in dogs.

Science.gov (United States)

Dahms, Irina; Beilstein, Paul; Bonnette, Kimberly; Salem, Norman

2016-06-01

DHA Ethyl Ester (DHA-EE) is a 90% concentrated ethyl ester of docosahexaenoic acid manufactured from the microalgal oil. The objective of the 9-month study was to evaluate safety of DHA-EE administered to beagle dogs at dose levels 150, 1000 and 2000 mg/kg bw/day by oral gavage and to determine reversibility of any findings after a 2-month recovery period. DHA-EE was well tolerated at all doses. There were observations of dry flaky skin with occasional reddened areas at doses ≥1000 mg/kg bw/day. These findings lacked any microscopic correlate and were no longer present after the recovery period. There were no toxicologically relevant findings in body weights, body weight gains, food consumption, ophthalmological examinations, and ECG measurements. Test article-related changes in hematology parameters were limited to decreases in reticulocyte count in the high-dose males and considered non-adverse. In clinical chemistry parameters, dose-related decreases in cholesterol and triglycerides levels were observed at all doses in males and females and attributed to the known lipid-lowering effects of DHA. There were no effects on other clinical chemistry, urinalysis or coagulation parameters. There were no abnormal histopathology findings attributed to test article. The No-Observable-Adverse-Effect Level of DHA-EE was established at 2000 mg/kg bw/day for both genders. Copyright © 2016 Elsevier Ltd. All rights reserved.

Distinct Analgesic Actions of DHA and DHA-Derived Specialized Pro-Resolving Mediators on Post-operative Pain After Bone Fracture in Mice.

Science.gov (United States)

Zhang, Linlin; Terrando, Niccolò; Xu, Zhen-Zhong; Bang, Sangsu; Jordt, Sven-Eric; Maixner, William; Serhan, Charles N; Ji, Ru-Rong

2018-01-01

Mechanisms of pain resolution are largely unclear. Increasing evidence suggests that specialized pro-resolving mediators (SPMs), derived from fish oil docosahexaenoic acid (DHA), promote the resolution of acute inflammation and potently inhibit inflammatory and neuropathic pain. In this study, we examined the analgesic impact of DHA and DHA-derived SPMs in a mouse model of post-operative pain induced by tibial bone fracture (fPOP). Intravenous perioperative treatment with DHA (500 μg), resolvin D1 (RvD1, 500 ng) and maresin 1 (MaR1, 500 ng), 10 min and 24 h after the surgery, delayed the development of fPOP (mechanical allodynia and cold allodynia). In contrast, post-operative intrathecal (IT) administration of DHA (500 μg) 2 weeks after the surgery had no effects on established mechanical and cold allodynia. However, by direct comparison, IT post-operative treatment (500 ng) with neuroprotectin D1 (NPD1), MaR1, and D-resolvins, RvD1 and RvD5, but not RvD3 and RvD4, effectively reduced mechanical and cold allodynia. ELISA analysis showed that perioperative DHA treatment increased RvD1 levels in serum and spinal cord samples after bone fracture. Interestingly, sham surgery resulted in transient allodynia and increased RvD1 levels, suggesting a correlation of enhanced SPM levels with acute pain resolution after sham surgery. Our findings suggest that (1) perioperative treatment with DHA is effective in preventing and delaying the development of fPOP and (2) post-treatment with some SPMs can attenuate established fPOP. Our data also indicate that orthopedic surgery impairs SPM production. Thus, DHA and DHA-derived SPMs should be differentially supplemented for treating fPOP and improving recovery.

Distinct Analgesic Actions of DHA and DHA-Derived Specialized Pro-Resolving Mediators on Post-operative Pain After Bone Fracture in Mice

Directory of Open Access Journals (Sweden)

Linlin Zhang

2018-05-01

Full Text Available Mechanisms of pain resolution are largely unclear. Increasing evidence suggests that specialized pro-resolving mediators (SPMs, derived from fish oil docosahexaenoic acid (DHA, promote the resolution of acute inflammation and potently inhibit inflammatory and neuropathic pain. In this study, we examined the analgesic impact of DHA and DHA-derived SPMs in a mouse model of post-operative pain induced by tibial bone fracture (fPOP. Intravenous perioperative treatment with DHA (500 μg, resolvin D1 (RvD1, 500 ng and maresin 1 (MaR1, 500 ng, 10 min and 24 h after the surgery, delayed the development of fPOP (mechanical allodynia and cold allodynia. In contrast, post-operative intrathecal (IT administration of DHA (500 μg 2 weeks after the surgery had no effects on established mechanical and cold allodynia. However, by direct comparison, IT post-operative treatment (500 ng with neuroprotectin D1 (NPD1, MaR1, and D-resolvins, RvD1 and RvD5, but not RvD3 and RvD4, effectively reduced mechanical and cold allodynia. ELISA analysis showed that perioperative DHA treatment increased RvD1 levels in serum and spinal cord samples after bone fracture. Interestingly, sham surgery resulted in transient allodynia and increased RvD1 levels, suggesting a correlation of enhanced SPM levels with acute pain resolution after sham surgery. Our findings suggest that (1 perioperative treatment with DHA is effective in preventing and delaying the development of fPOP and (2 post-treatment with some SPMs can attenuate established fPOP. Our data also indicate that orthopedic surgery impairs SPM production. Thus, DHA and DHA-derived SPMs should be differentially supplemented for treating fPOP and improving recovery.

Inhibition of dehydrogenase activity in petroleum refinery wastewater bacteria by phenolic compounds

OpenAIRE

Gideon C. Okpokwasili; Christian Okechukwu Nweke

2010-01-01

The toxicity of phenol, 2-nitrophenol, 4-nitrophenol, 2,4-dinitrophenol, 2-chlorophenol, 4-chlorophenol, 4-bromophenol and 3,5-dimethylphenol on Pseudomonas, Bacillus and Escherichia species isolated from petroleum refinery wastewater was assessed via inhibition of dehydrogenase enzyme activity. At low concentrations, 2-nitrophenol, 2-chlorophenol, 4-chlorophenol, 4-bromophenol and 3,5-dimethylphenol stimulated dehydrogenase activity and at sufficient concentrations, phenolic compounds inhibi...

Serum creatine kinase and lactate dehydrogenase activities in ...

African Journals Online (AJOL)

... in thyroid function are common endocrine disorders affecting 5-10% of individuals over ... Key words: Hyperthyroidism, hypothyroidism, lactate dehydrogenase, serum creatine kinase ... individuals depends on age, race, lean body mass and physical activity. ... measured by radioimmunoassay on AXSYM System (Abbott.

Effect of albumin-bound DHA on phosphoinositide phosphorylation in collagen stimulated human platelets

International Nuclear Information System (INIS)

Gaudette, D.C.; Holub, B.J.

1990-01-01

The effect of exogenous albumin-bound docosahexaenoic acid (22:6n-3) (DHA), arachidonic acid (20:4n-6) (AA), and eicosapendaenoic acid (20:5n-3) (EPA) on phosphoinositide metabolism following collagen stimulation was studied using [3H]inositol prelabelled platelets. Collagen stimulation (3 min, 1.8 micrograms/ml) increased the labelling of both phosphatidylinositol 4-monophosphate (PIP), and phosphatidylinositol 4,5-biphosphate (PIP2). Of the fatty acids tested, only pre-incubation (2 min) with DHA (20 microM) significantly attenuated the collagen-induced increased PIP and PIP2 labelling; EPA was without effect, while AA enhanced PIP labelling. Forty microM DHA was less effective at attenuating the increased PIP and PIP2 labelling even though this concentration of DHA resulted in greater inhibition of platelet aggregation. Neither concentration of DHA attenuated the increased polyphosphoinositide labelling resulting from stimulation by the endoperoxide analogue U46619, or the phorbol ester, PMA. These data suggest that the effect of DHA on attenuating the increased PIP and PIP2 labelling following collagen stimulation likely occurs before thromboxane receptor occupancy, may not occur at the level of protein kinase C activation, and could be mediated in part via a lessened synthesis of thromboxane A2

DHA involvement in neurotransmission process

OpenAIRE

Vancassel Sylvie; Aïd Sabah; Denis Isabelle; Guesnet Philippe; Lavialle Monique

2007-01-01

The very high enrichment of the nervous system in the polyunsaturated fatty acids, arachidonic (AA, 20: 4n-6) and docosahexaenoic acids (DHA, 22: 6n-3), is dependant of the dietary availability of their respective precursors, linoleic (18: 2n-6) and_-linolenic acids (18: 3n-3). Inadequate amounts of DHA in brain membranes have been linked to a wide variety of abnormalities ranging from visual acuity and learning irregularities, to psychopathologies. However, the molecular mechanisms involved ...

Maternal DHA levels and Toddler Free-Play Attention

OpenAIRE

Kannass, Kathleen N.; Colombo, John; Carlson, Susan E.

2009-01-01

We investigated the relationship between maternal docosahexaenoic acid (DHA) levels at birth and toddler free-play attention in the second year. Toddler free-play attention was assessed at 12 and 18 months, and maternal erythrocyte (red-blood cell; RBC) phospholipid DHA (percentage of total fatty acids) was measured from mothers at delivery. Overall, higher maternal DHA status at birth was associated with enhanced attentional functioning during the second year. Toddlers whose mothers had high...

Crystallization and preliminary X-ray diffraction analysis of the wild-type haloalkane dehalogenase DhaA and its variant DhaA13 complexed with different ligands

International Nuclear Information System (INIS)

Stsiapanava, Alena; Chaloupkova, Radka; Fortova, Andrea; Brynda, Jiri; Weiss, Manfred S.; Damborsky, Jiri; Kuta Smatanova, Ivana

2011-01-01

Crystals of the wild-type haloalkane dehalogenase DhaA derived from R. rhodochrous NCIMB 13064 and of its catalytically inactive variant DhaA13 were grown in the presence of various ligands and diffraction data were collected to high and atomic resolution. Haloalkane dehalogenases make up an important class of hydrolytic enzymes which catalyse the cleavage of carbon–halogen bonds in halogenated aliphatic compounds. There is growing interest in these enzymes owing to their potential use in environmental and industrial applications. The haloalkane dehalogenase DhaA from Rhodococcus rhodochrous NCIMB 13064 can slowly detoxify the industrial pollutant 1,2,3-trichloropropane (TCP). Structural analysis of this enzyme complexed with target ligands was conducted in order to obtain detailed information about the structural limitations of its catalytic properties. In this study, the crystallization and preliminary X-ray analysis of complexes of wild-type DhaA with 2-propanol and with TCP and of complexes of the catalytically inactive variant DhaA13 with the dye coumarin and with TCP are described. The crystals of wild-type DhaA were plate-shaped and belonged to the triclinic space group P1, while the variant DhaA13 can form prism-shaped crystals belonging to the orthorhombic space group P2 1 2 1 2 1 as well as plate-shaped crystals belonging to the triclinic space group P1. Diffraction data for crystals of wild-type DhaA grown from crystallization solutions with different concentrations of 2-propanol were collected to 1.70 and 1.26 Å resolution, respectively. A prism-shaped crystal of DhaA13 complexed with TCP and a plate-shaped crystal of the same variant complexed with the dye coumarin diffracted X-rays to 1.60 and 1.33 Å resolution, respectively. A crystal of wild-type DhaA and a plate-shaped crystal of DhaA13, both complexed with TCP, diffracted to atomic resolutions of 1.04 and 0.97 Å, respectively

Use of a novel docosahexaenoic acid (DHA) formulation versus control in a neonatal porcine model of short bowel syndrome leads to greater intestinal absorption and higher systemic levels of DHA

Science.gov (United States)

Martin, Camilia R.; Stoll, Barbara; Cluette-Brown, Joanne; Akinkuotu, Adesola C.; Olutoye, Oluyinka O.; Gura, Kathleen M.; Singh, Pratibha; Zaman, Munir M.; Perillo, Michael C.; Puder, Mark; Freedman, Steven D.; Burrin, Doug

2017-01-01

Infants with short bowel syndrome (SBS) are at high risk for malabsorption, malnutrition, and failure to thrive. The objective of this study was to evaluate in a porcine model of SBS, the systemic absorption of a novel enteral Docosahexaenoic acid (DHA) formulation that forms micelles independent of bile salts (DHA-ALT®). We hypothesized that enteral delivery of DHA-ALT® would result in higher blood levels of DHA compared to a control DHA preparation due to improved intestinal absorption. SBS was induced in term piglets through a 75% mid-jejunoileal resection and the piglets randomized to either DHA-ALT® or control DHA formulation (N=5 per group) for 4 postoperative days. The median ± IQR difference in final versus starting weight was 696 ± 425g in the DHA-ALT® group compared to 132 ± 278g in the controls (p=.08). Within 12 hours, median ± IQR DHA and eicosapentaenoic acid plasma levels (mol%) were significantly higher in the DHA-ALT® vs. control group (4.1 ± 0.3 vs 2.5 ± 0.5, p=0.009; 0.7 ± 0.3 vs 0.2 ± 0.005, p=0.009, respectively). There were lower fecal losses of DHA and greater ileal tissue incorporation with DHA-ALT® versus the control. Morphometric analyses demonstrated an increase in proximal jejunum and distal ileum villus height in the DHA-ALT® group compared to controls (p=0.01). In a neonatal porcine model of SBS, enteral administration of a novel DHA preparation that forms micelles independent of bile salts resulted in increased fatty acid absorption, increased ileal tissue incorporation, and increased systemic levels of DHA. PMID:28385289

A maternal erythrocyte DHA content of approximately 6 g% is the DHA status at which intrauterine DHA biomagnifications turns into bioattenuation and postnatal infant DHA equilibrium isreached

NARCIS (Netherlands)

Luxwolda, Martine F.; Kuipers, Remko S.; Sango, Wicklif S.; Kwesigabo, Gideon; Dijck-Brouwer, D. A. Janneke; Muskiet, Frits A. J.

Higher long-chain polyunsaturated fatty acids (LCP) in infant compared with maternal lipids at delivery is named biomagnification. The decline of infant and maternal docosahexaenoic acid (DHA) status during lactation in Western countries suggests maternal depletion. We investigated whether

Effect of DHA on plasma fatty acid availability and oxidative stress during training season and football exercise.

Science.gov (United States)

Martorell, Miquel; Capó, Xavier; Sureda, Antoni; Batle, Joan M; Llompart, Isabel; Argelich, Emma; Tur, Josep A; Pons, Antoni

2014-08-01

The aim was to determine the effects of a diet supplemented with 1.14 g per day of docosahexaenoic acid (DHA) for eight weeks on the plasma oxidative balance and anti-inflammatory markers after training and acute exercise. Fifteen volunteer male football players were randomly assigned to placebo or experimental and supplemented groups. Blood samples were taken under resting conditions at the beginning and after eight weeks of training under resting and post-exercise conditions. The experimental beverage increased the plasma DHA availability in non-esterified fatty acids (NEFAs) and triglyceride fatty acids (TGFAs) and increased the polyunsaturated fatty acid (PUFA) fraction of NEFAs but had no effects on the biomarkers for oxidative balance in plasma. During training, plasma protein markers of oxidative damage, the haemolysis degree and the antioxidant enzyme activities increased, but did not affect lipid oxidative damage. Training season and DHA influenced the circulating levels of prostaglandin E2 (PGE2). Acute exercise did not alter the basal levels of plasma markers for oxidative and nitrosative damage of proteins and lipids, and the antioxidant enzyme activities, although DHA-diet supplementation significantly increased the PGE2 in plasma after acute exercise. In conclusion, the training season and acute exercise, but not the DHA diet supplementation, altered the pattern of plasma oxidative damage, as the antioxidant system proved sufficient to prevent the oxidative damage induced by the acute exercise in well-trained footballers. The DHA-diet supplementation increased the prostaglandin PGE2 plasma evidencing anti-inflammatory effects of DHA to control inflammation after acute exercise.

Metabolic engineering Camelina sativa with fish oil-like levels of DHA.

Directory of Open Access Journals (Sweden)

James R Petrie

Full Text Available BACKGROUND: Omega-3 long-chain (≥C20 polyunsaturated fatty acids (ω3 LC-PUFA such as eicosapentaenoic acid (EPA and docosahexaenoic acid (DHA are critical for human health and development [corrected].. Numerous studies have indicated that deficiencies in these fatty acids can increase the risk or severity of cardiovascular, inflammatory and other diseases or disorders. EPA and DHA are predominantly sourced from marine fish although the primary producers are microalgae. Much work has been done to engineer a sustainable land-based source of EPA and DHA to reduce pressure on fish stocks in meeting future demand, with previous studies describing the production of fish oil-like levels of DHA in the model plant species, Arabidopsis thaliana. PRINCIPAL FINDINGS: In this study we describe the production of fish oil-like levels (>12% of DHA in the oilseed crop species Camelina sativa achieving a high ω3/ω6 ratio. The construct previously transformed in Arabidopsis as well as two modified construct versions designed to increase DHA production were used. DHA was found to be stable to at least the T5 generation and the EPA and DHA were found to be predominantly at the sn-1,3 positions of triacylglycerols. Transgenic and parental lines did not have different germination or seedling establishment rates. CONCLUSIONS: DHA can be produced at fish oil-like levels in industrially-relevant oilseed crop species using multi-gene construct designs which are stable over multiple generations. This study has implications for the future of sustainable EPA and DHA production from land-based sources.

DHA supplementation during pregnancy does not reduce BMI or body fat mass in children: follow-up of the DHA to Optimize Mother Infant Outcome randomized controlled trial.

Science.gov (United States)

Muhlhausler, Beverly S; Yelland, Lisa N; McDermott, Robyn; Tapsell, Linda; McPhee, Andrew; Gibson, Robert A; Makrides, Maria

2016-06-01

The omega-3 (n-3) long-chain polyunsaturated fatty acid (LCPUFA) docosahexaenoic acid (DHA) has proven effective at reducing fat storage in animal studies. However, a systematic review of human trials showed a lack of quality data to support or refute this hypothesis. We sought to determine whether maternal DHA supplementation during the second half of pregnancy results in a lower body mass index (BMI) and percentage of body fat in children. We conducted a follow-up at 3 and 5 y of age of children who were born to mothers enrolled in the DOMInO (DHA to Optimize Mother Infant Outcome) double-blind, randomized controlled trial, in which women with a singleton pregnancy were provided with DHA-rich fish-oil capsules (800 mg DHA/d) or vegetable-oil capsules (control group) in the second half of pregnancy. Primary outcomes were the BMI z score and percentage of body fat at 3 and 5 y of age. Potential interactions between prenatal DHA and the peroxisome proliferator-activated receptor-γ (PPARγ) genotype as a measure of the genetic predisposition to obesity were investigated. A total of 1614 children were eligible for the follow-up. Parent or caregiver consent was obtained for 1531 children (95%), and these children were included in the analysis. BMI z scores and percentages of body fat of children in the DHA group did not differ from those of children in the control group at either 3 y of age [BMI z score adjusted mean difference: 0.03 (95% CI: -0.07, 0.13; P = 0.61); percentage of body fat adjusted mean difference: -0.26 (95% CI: -0.99, 0.46; P = 0.47)] or 5 y of age [BMI z score adjusted mean difference: 0.02 (95% CI: -0.08, 0.12; P = 0.66); percentage of body fat adjusted mean difference: 0.11 (95% CI: -0.60, 0.82; P = 0.75)]. No treatment effects were modified by the PPARγ genotype of the child. Independent of a genetic predisposition to obesity, maternal intake of DHA-rich fish oil during the second half of pregnancy does not affect the growth or body composition

Docosahexaenoic acid (DHA) at the sn-2 position of triacylglycerols increases DHA incorporation in brown, but not in white adipose tissue, of hamsters.

Science.gov (United States)

Lopes, Paula A; Bandarra, Narcisa M; Martins, Susana V; Madeira, Marta S; Ferreira, Júlia; Guil-Guerrero, José L; Prates, José A M

2018-06-01

We hypothesised that the incorporation of docosahexaenoic acid (DHA) across adipose tissues will be higher when it is ingested as triacylglycerols (TAG) structured at the sn-2 position. Ten-week old male hamsters were allocated to 4 dietary treatments (n = 10): linseed oil (LSO-control group), fish oil (FO), fish oil ethyl esters (FO-EE) and structured DHA at the sn-2 position of TAG (DHA-SL) during 12 weeks. In opposition to the large variations found for fatty acid composition in retroperitoneal white adipose tissue (WAT), brown adipose tissue (BAT) was less responsive to diets. DHA was not found in subcutaneous and retroperitoneal WAT depots but it was successfully incorporated in BAT reaching the highest percentage in DHA-SL. The PCA on plasma hormones (insulin, leptin, adiponectin) and fatty acids discriminated BAT from WATs pointing towards an individual signature on fatty acid deposition, but did not allow for full discrimination of dietary treatments within each adipose tissue.

Crystallization and preliminary X-ray diffraction analysis of the wild-type haloalkane dehalogenase DhaA and its variant DhaA13 complexed with different ligands.

Science.gov (United States)

Stsiapanava, Alena; Chaloupkova, Radka; Fortova, Andrea; Brynda, Jiri; Weiss, Manfred S; Damborsky, Jiri; Smatanova, Ivana Kuta

2011-02-01

Haloalkane dehalogenases make up an important class of hydrolytic enzymes which catalyse the cleavage of carbon-halogen bonds in halogenated aliphatic compounds. There is growing interest in these enzymes owing to their potential use in environmental and industrial applications. The haloalkane dehalogenase DhaA from Rhodococcus rhodochrous NCIMB 13064 can slowly detoxify the industrial pollutant 1,2,3-trichloropropane (TCP). Structural analysis of this enzyme complexed with target ligands was conducted in order to obtain detailed information about the structural limitations of its catalytic properties. In this study, the crystallization and preliminary X-ray analysis of complexes of wild-type DhaA with 2-propanol and with TCP and of complexes of the catalytically inactive variant DhaA13 with the dye coumarin and with TCP are described. The crystals of wild-type DhaA were plate-shaped and belonged to the triclinic space group P1, while the variant DhaA13 can form prism-shaped crystals belonging to the orthorhombic space group P2(1)2(1)2(1) as well as plate-shaped crystals belonging to the triclinic space group P1. Diffraction data for crystals of wild-type DhaA grown from crystallization solutions with different concentrations of 2-propanol were collected to 1.70 and 1.26 Å resolution, respectively. A prism-shaped crystal of DhaA13 complexed with TCP and a plate-shaped crystal of the same variant complexed with the dye coumarin diffracted X-rays to 1.60 and 1.33 Å resolution, respectively. A crystal of wild-type DhaA and a plate-shaped crystal of DhaA13, both complexed with TCP, diffracted to atomic resolutions of 1.04 and 0.97 Å, respectively.

DHA involvement in neurotransmission process

Directory of Open Access Journals (Sweden)

Vancassel Sylvie

2007-05-01

Full Text Available The very high enrichment of the nervous system in the polyunsaturated fatty acids, arachidonic (AA, 20: 4n-6 and docosahexaenoic acids (DHA, 22: 6n-3, is dependant of the dietary availability of their respective precursors, linoleic (18: 2n-6 and_-linolenic acids (18: 3n-3. Inadequate amounts of DHA in brain membranes have been linked to a wide variety of abnormalities ranging from visual acuity and learning irregularities, to psychopathologies. However, the molecular mechanisms involved remain unknown. Several years ago, we hypothesized that a modification of DHA contents of neuronal membranes by dietary modulation could change the neurotransmission function and then underlie inappropriate behavioural response. We showed that, in parallel to a severe loss of brain DHA concomitant to a compensatory substitution by 22:5n-6, the dietary lack of α-linolenic acid during development induced important changes in the release of neurotransmitters (dopamine, serotonin, acetylcholine in cerebral areas specifically involved in learning, memory and reward processes. Data suggested alteration of presynaptic storage process and dysregulations of reciprocal functional interactions between monoaminergic and cholinergic pathways. Moreover, we showed that recovery of these neurochemical changes was possible when the deficient diet was switched to a diet balanced in n-3 and n-6 PUFA before weaning. The next step is to understand the mechanism involved. Particularly, we focus on the study of the metabolic cooperation between the endothelial cell, the astrocyte and the neuron which regulate synaptic transmission.These works could contribute to the understanding of the link between some neuropsychiatric disorders and the metabolism of n-3 PUFA, through their action on neurotransmission.

15-hydroxyprostaglandin dehydrogenase activity in vitro in lung and kidney of essential fatty acid-deficient rats

DEFF Research Database (Denmark)

Hansen, Harald S.; Toft, B.S.

1978-01-01

Weanling rats were fed for 6 months on a diet deficient in essential fatty acids: either fat-free, or with 28% (w/w) partially hydrogenated fish oil. Control rats were fed a diet with 28% (w/w) arachis oil for 6 months. 15-Hydroxyprostaglandin dehydrogenase activity was determined as initial rates...... of the two groups on diets deficient in essential fatty acids as compared to the control group. No difference was observed in dehydrogenase activity in the kidneys. The dehydrogenase may be of importance for the regulation of the level of endogenous prostaglandins and, thus, a decrease in activity could...

Orthodontic Force Application in Correlation with Salivary Lactate Dehydrogenase Activity

Directory of Open Access Journals (Sweden)

Erik Husin

2013-07-01

Full Text Available Orthodontic tooth movement generate mechanical forces to periodontal ligament and alveolar bone. The forces correlate with initial responses of periodontal tissues and involving many metabolic changes. One of the metabolic changes detected in saliva is lactate dehydrogenase (LDH activity. Objectives: To evaluate the correlation between orthodontic interrupted force application, lactate dehydrogenase activity and the distance of tooth movement. Methods: upper premolar, pre-retraction of upper canine and 1, 7, 14, 21 and 28 days post-retraction of upper canine with 100g interrupted orthodontic force. Results: duration of force (F=11.926 p 14 and 28 days post-retraction of canine. The region of retraction correlated with the distance of tooth movement (F=7.377 p=0.007. The duration of force correlated with the distance of tooth movement (F=66.554 p=0.000. retraction of canine. Conclusion: This study concluded that orthodontic interrupted force application on canine could increase the distance of tooth movement and LDH activity in saliva.

Mechanism of the modulation of BK potassium channel complexes with different auxiliary subunit compositions by the omega-3 fatty acid DHA.

Science.gov (United States)

Hoshi, Toshinori; Tian, Yutao; Xu, Rong; Heinemann, Stefan H; Hou, Shangwei

2013-03-19

Large-conductance Ca(2+)- and voltage-activated K(+) (BK) channels are well known for their functional versatility, which is bestowed in part by their rich modulatory repertoire. We recently showed that long-chain omega-3 polyunsaturated fatty acids such as docosahexaenoic acid (DHA) found in oily fish lower blood pressure by activating vascular BK channels made of Slo1+β1 subunits. Here we examined the action of DHA on BK channels with different auxiliary subunit compositions. Neuronal Slo1+β4 channels were just as well activated by DHA as vascular Slo1+β1 channels. In contrast, the stimulatory effect of DHA was much smaller in Slo1+β2, Slo1+LRRC26 (γ1), and Slo1 channels without auxiliary subunits. Mutagenesis of β1, β2, and β4 showed that the large effect of DHA in Slo1+β1 and Slo1+β4 is conferred by the presence of two residues, one in the N terminus and the other in the first transmembrane segment of the β1 and β4 subunits. Transfer of this amino acid pair from β1 or β4 to β2 introduces a large response to DHA in Slo1+β2. The presence of a pair of oppositely charged residues at the aforementioned positions in β subunits is associated with a large response to DHA. The Slo1 auxiliary subunits are expressed in a highly tissue-dependent fashion. Thus, the subunit composition-dependent stimulation by DHA demonstrates that BK channels are effectors of omega-3 fatty acids with marked tissue specificity.

One-generation reproductive toxicity study of DHA-rich oil in rats

NARCIS (Netherlands)

Blum, R.; Kiy, T.; Waalkens-Berendsen, I.; Wong, A.W.; Roberts, A.

2007-01-01

Polyunsaturated fatty acids, including docosahexaenoic acid (DHA), are natural constituents of the human diet. DHA-algal oil is produced through the use of the marine protist, Ulkenia sp. The reproductive toxicity of DHA-algal oil was assessed in a one-generation study. Rats were provided diets

Effect of α-linolenic acid and DHA intake on lipogenesis and gene expression involved in fatty acid metabolism in growing-finishing pigs.

Science.gov (United States)

De Tonnac, A; Labussière, E; Vincent, A; Mourot, J

2016-07-01

The regulation of lipogenesis mechanisms related to consumption of n-3 PUFA is poorly understood. The aim of the present study was to find out whether α-linolenic acid (ALA) or DHA uptake can have an effect on activities and gene expressions of enzymes involved in lipid metabolism in the liver, subcutaneous adipose tissue and longissimus dorsi (LD) muscle of growing-finishing pigs. Six groups of ten pigs received one of six experimental diets supplemented with rapeseed oil in the control diet, extruded linseed, microalgae or a mixture of both to implement different levels of ALA and DHA with the same content in total n-3. Results were analysed for linear and quadratic effects of DHA intake. The results showed that activities of malic enzyme (ME) and fatty acid synthase (FAS) decreased linearly in the liver with dietary DHA. Although the expression of the genes of these enzymes and their activities were poorly correlated, ME and FAS expressions also decreased linearly with DHA intake. The intake of DHA down-regulates the expressions of other genes involved in fatty acid (FA) metabolism in some tissues of pigs, such as fatty acid desaturase 2 and sterol-regulatory element binding transcription factor 1 in the liver and 2,4-dienoyl CoA reductase 2 in the LD muscle. FA oxidation in the LD muscle and FA synthesis decreased in the liver with increasing amount of dietary DHA, whereas a retroconversion of DHA into EPA seems to be set up in this last tissue.

Determination of dehydrogenase activities involved in D-glucose oxidation in Gluconobacter and Acetobacter strains

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Florencia Sainz

2016-08-01

Full Text Available Acetic acid bacteria (AAB are known for rapid and incomplete oxidation of an extensively variety of alcohols and carbohydrates, resulting in the accumulation of organic acids as the final products. These oxidative fermentations in AAB are catalyzed by PQQ- or FAD- dependent membrane bound dehydrogenases. In the present study, the enzyme activity of the membrane bound dehydrogenases (membrane-bound PQQ-glucose dehydrogenase (mGDH, D-gluconate dehydrogenase (GADH and membrane-bound glycerol dehydrogenase (GLDH involved in the oxidation of D-glucose and D-gluconic acid (GA was determined in six strains of three different species of AAB (three natural and three type strains. Moreover, the effect of these activities on the production of related metabolites (GA, 2-keto-D-gluconic acid (2KGA and 5-keto-D-gluconic acid (5KGA was analyzed. The natural strains belonging to Gluconobacter showed a high mGDH activity and low activity in GADH and GLDH, whereas the A. malorum strain presented low activity in the three enzymes. Nevertheless, no correlation was observed between the activity of these enzymes and the concentration of the corresponding metabolites. In fact, all the tested strains were able to oxidize D-glucose to GA, being maximal at the late exponential phase of the AAB growth (24 h, which coincided with glucose exhaustion and the maximum mGDH activity. Instead, only some of the tested strains were capable of producing 2KGA and/or 5KGA. In the case of G. oxydans strains, no 2KGA production was detected which is related to the absence of GADH activity after 24 h, while in the remaining strains, detection of GADH activity after 24h resulted in a high accumulation of 2KGA. Therefore, it is possible to choose the best strain depending on the desired product composition.Moreover, the sequences of these genes were used to construct phylogenetic trees. According to the sequence of gcd, gene coding for mGDH, Acetobacter and Komagataeibacter were

Potentiation of insulin release in response to amino acid methyl esters correlates to activation of islet glutamate dehydrogenase activity

DEFF Research Database (Denmark)

Kofod, Hans; Lernmark, A; Hedeskov, C J

1986-01-01

Column perifusion of mouse pancreatic islets was used to study the ability of amino acids and their methyl esters to influence insulin release and activate islet glutamate dehydrogenase activity. In the absence of L-glutamine, L-serine and the methyl ester of L-phenylalanine, but neither L...... glutamate dehydrogenase activity showed that only the two methyl esters of L-phenylalanine and L-serine activated the enzyme. It is concluded that the mechanism by which methyl esters of amino acids potentiate insulin release is most likely to be mediated by the activation of pancreatic beta-cell glutamate...

N-3 polyunsaturated fatty acid DHA during IVM affected oocyte developmental competence in cattle.

Science.gov (United States)

Oseikria, Mouhamad; Elis, Sébastien; Maillard, Virginie; Corbin, Emilie; Uzbekova, Svetlana

2016-06-01

The positive effect of n-3 polyunsaturated fatty acids (FAs) on fertility in ruminants seems to be partly mediated through direct effects on the oocyte developmental potential. We aimed to investigate whether supplementation with physiological levels of docosahexaenoic acid (DHA, C22:6 n-3 polyunsaturated fatty acids) during IVM has an effect on oocyte maturation and in vitro embryo development in cattle. We reported that DHA (0, 1, 10, or 100 μM) had no effect on oocyte viability or maturation rate after 22-hour IVM. Incubation of oocyte-cumulus complexes with 1-μM DHA during IVM significantly increased (P DHA during IVM also induced a significant increase in the blastocyst rate at Day 7 after IVF as compared with control (30.6% vs. 17.6%, respectively) and tended to increase the number of cells in the blastocysts (97.1 ± 4.9 vs. 81.2 ± 5.3, respectively; P = 0.08). On the contrary, 10-μM DHA had no effects, whereas 100-μM DHA significantly decreased the cleavage rate compared with control (69.5% vs.78.8%, respectively) and the greater than 4-cell embryo rate at Day 2 after parthenogenetic activation (19.5% vs. 29.7%). As was shown by real-time polymerase chain reaction, negative effects of 100-μM DHA were associated with significant increase of progesterone synthesis by oocyte-cumulus complexes, a three-fold increase in expression level of FA transporter CD36 and a two-fold decrease of FA synthase FASN genes in cumulus cells (CCs) of corresponding oocytes. Docosahexaenoic acid at 1 and 10 μM had no effect on expression of those and other key lipid metabolism-related genes in CC. In conclusion, administration of a low physiological dose of DHA (1 μM) during IVM may have beneficial effects on oocyte developmental competence in vitro without affecting lipid metabolism gene expression in surrounding CCs, contrarily to 100 μM DHA which diminished oocyte quality associated with perturbation of lipid and steroid metabolism in CC. Copyright © 2016

Intrauterine, postpartum and adult relationships between arachidonic acid (AA) and docosahexaenoic acid (DHA)

NARCIS (Netherlands)

Kuipers, Remko S.; Luxwolda, Martine F.; Dijck-Brouwer, D. A. Janneke; Muskiet, Frits A. J.

Erythrocyte (RBC) fatty acid compositions from populations with stable dietary habits but large variations in RBC-arachidonic (AA) and RBC-docosahexaenoic acid (DHA) provided us with insight into relationships between DHA and AA. It also enabled us to estimate the maternal RBC-DHA (mRBC-DHA) status

Docosahexaenoic Acid (DHA: An Ancient Nutrient for the Modern Human Brain

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Joanne Bradbury

2011-05-01

Full Text Available Modern humans have evolved with a staple source of preformed docosahexaenoic acid (DHA in the diet. An important turning point in human evolution was the discovery of high-quality, easily digested nutrients from coastal seafood and inland freshwater sources. Multi-generational exploitation of seafood by shore-based dwellers coincided with the rapid expansion of grey matter in the cerebral cortex, which characterizes the modern human brain. The DHA molecule has unique structural properties that appear to provide optimal conditions for a wide range of cell membrane functions. This has particular implications for grey matter, which is membrane-rich tissue. An important metabolic role for DHA has recently been identified as the precursor for resolvins and protectins. The rudimentary source of DHA is marine algae; therefore it is found concentrated in fish and marine oils. Unlike the photosynthetic cells in algae and higher plants, mammalian cells lack the specific enzymes required for the de novo synthesis of alpha-linolenic acid (ALA, the precursor for all omega-3 fatty acid syntheses. Endogenous synthesis of DHA from ALA in humans is much lower and more limited than previously assumed. The excessive consumption of omega-6 fatty acids in the modern Western diet further displaces DHA from membrane phospholipids. An emerging body of research is exploring a unique role for DHA in neurodevelopment and the prevention of neuropsychiatric and neurodegenerative disorders. DHA is increasingly being added back into the food supply as fish oil or algal oil supplementation.

Docosahexaenoic acid (DHA): an ancient nutrient for the modern human brain.

Science.gov (United States)

Bradbury, Joanne

2011-05-01

Modern humans have evolved with a staple source of preformed docosahexaenoic acid (DHA) in the diet. An important turning point in human evolution was the discovery of high-quality, easily digested nutrients from coastal seafood and inland freshwater sources. Multi-generational exploitation of seafood by shore-based dwellers coincided with the rapid expansion of grey matter in the cerebral cortex, which characterizes the modern human brain. The DHA molecule has unique structural properties that appear to provide optimal conditions for a wide range of cell membrane functions. This has particular implications for grey matter, which is membrane-rich tissue. An important metabolic role for DHA has recently been identified as the precursor for resolvins and protectins. The rudimentary source of DHA is marine algae; therefore it is found concentrated in fish and marine oils. Unlike the photosynthetic cells in algae and higher plants, mammalian cells lack the specific enzymes required for the de novo synthesis of alpha-linolenic acid (ALA), the precursor for all omega-3 fatty acid syntheses. Endogenous synthesis of DHA from ALA in humans is much lower and more limited than previously assumed. The excessive consumption of omega-6 fatty acids in the modern Western diet further displaces DHA from membrane phospholipids. An emerging body of research is exploring a unique role for DHA in neurodevelopment and the prevention of neuropsychiatric and neurodegenerative disorders. DHA is increasingly being added back into the food supply as fish oil or algal oil supplementation.

Omega-3 fatty acids, EPA and DHA induce apoptosis and enhance drug sensitivity in multiple myeloma cells but not in normal peripheral mononuclear cells.

Science.gov (United States)

Abdi, J; Garssen, J; Faber, J; Redegeld, F A

2014-12-01

The n-3 polyunsaturated fatty acids eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) have been shown to enhance the effect of chemotherapeutic drugs in clinical studies in cancer patients and to induce apoptotic tumor cell death in vitro. Until now, EPA and DHA have never been investigated in multiple myeloma (MM). Human myeloma cells (L363, OPM-1, OPM-2 and U266) and normal peripheral blood mononuclear cells were exposed to EPA and DHA, and effects on mitochondrial function and apoptosis, caspase-3 activation, gene expression and drug toxicity were measured. Exposure to EPA and DHA induced apoptosis and increased sensitivity to bortezomib in MM cells. Importantly, they did not affect viability of normal human peripheral mononuclear cells. Messenger RNA expression arrays showed that EPA and DHA modulated genes involved in multiple signaling pathways including nuclear factor (NF) κB, Notch, Hedgehog, oxidative stress and Wnt. EPA and DHA inhibited NFκB activity and induced apoptosis through mitochondrial perturbation and caspase-3 activation. Our study suggests that EPA and DHA induce selective cytotoxic effects in MM and increase sensitivity to bortezomib and calls for further exploration into a potential application of these n-3 polyunsaturated fatty acids in the therapy of MM. Copyright © 2014 Elsevier Inc. All rights reserved.

The relation between the omega-3 index and arachidonic acid is bell shaped : Synergistic at low EPA plus DHA status and antagonistic at high EPA plus DHA status

NARCIS (Netherlands)

Luxwolda, Martine F.; Kuipers, Remko S.; Smit, Ella N.; Velzing-Aarts, Francien V.; Dijck-Brouwer, D. A. Janneke; Muskiet, Frits A. J.

2011-01-01

Introduction: The relation between docosahexaenoic (DHA) and eicosapentaenoic (EPA) vs. arachidonic acid (AA) seems characterized by both synergism and antagonism. Materials and methods: Investigate the relation between EPA + DHA and AA in populations with a wide range of EPA + DHA status and across

Maternal DHA supplementation protects rat offspring against impairment of learning and memory following prenatal exposure to valproic acid.

Science.gov (United States)

Gao, Jingquan; Wu, Hongmei; Cao, Yonggang; Liang, Shuang; Sun, Caihong; Wang, Peng; Wang, Ji; Sun, Hongli; Wu, Lijie

2016-09-01

Docosahexaenoic acid (22:6n-3; DHA) is known to play a critical role in postnatal brain development. However, there have been no studies investigating the preventive effect of DHA on prenatal valproic acid (VPA)-induced behavioral and molecular alterations in offspring. The present study was to evaluate the neuroprotective effects in offspring using maternal feeding of DHA to rats exposed to VPA in pregnancy. In the present study, rats were exposed to VPA on day 12.5 of pregnancy; DHA was administered at the dosages of 100, 300 and 500 mg/kg/day for 3 weeks from day 1 to 21 of pregnancy. The results showed that maternal feeding of DHA to the prenatal exposed to VPA (1) prevented VPA-induced learning and memory impairment but did not change social-related behavior, (2) increased total DHA content in offspring plasma and hippocampus, (3) rescued VPA-induced neuronal loss and apoptosis of pyramidal cells in hippocampal CA1, (4) influenced the content of malondialdehyde and glutathione and the activities of superoxide dismutase and glutathione in the hippocampus, (5) altered levels of apoptosis-related proteins (Bcl-2, Bax and caspase-3) and inhibited the activity of caspase-3 in offspring hippocampus and (6) enhanced relative levels of p-CaMKII and p-CREB proteins in the hippocampus. These findings suggest that maternal feeding with DHA may prevent prenatal VPA-induced impairment of learning and memory, normalize several different molecules associated with oxidative stress and apoptosis in the hippocampus of offspring, and exert preventive effects on prenatal VPA-induced brain dysfunction. Copyright © 2016 Elsevier Inc. All rights reserved.

Lipidomic analysis of Arabidopsis seed genetically engineered to contain DHA

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Xue-Rong eZhou

2014-09-01

Full Text Available Metabolic engineering of omega-3 long-chain (≥C20 polyunsaturated fatty acids (ω3 LC-PUFA in oilseeds has been one of the key metabolic engineering targets in recent years. By expressing a transgenic pathway for enhancing the synthesis of the ω3 LC-PUFA docosahexaenoic acid (DHA from endogenous -linolenic acid (ALA, we obtained the production of fish oil-like proportions of DHA in Arabidopsis seed oil. Liquid chromatography-mass spectrometry (LC-MS was used to characterize the triacylglycerol (TAG, diacylglycerol (DAG and phospholipid (PL lipid classes in the transgenic and wild type Arabidopsis seeds at both developing and mature stages. The analysis identified the appearance of several abundant DHA-containing phosphatidylcholine (PC, DAG and TAG molecular species in mature seeds. The relative abundances of PL, DAG and TAG species showed a preferred combination of LC-PUFA with ALA in the transgenic seeds, where LC-PUFA were esterified in positions usually occupied by 20:1ω9. Trace amounts of di-DHA PC and tri-DHA TAG were identified, and confirmed by high resolution MS/MS. Studying the lipidome in transgenic seeds provides insights into where DHA accumulated and composed with other fatty acids of neutral and phospholipids from the developing and mature seeds.

Specific uptake of DHA by the brain from a structured phospholipid, AceDoPC®

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Bernoud-Hubac Nathalie

2017-03-01

Full Text Available Docosahexaenoic acid (DHA; 22:6 ω-3 is highly enriched in the brain and is required for proper brain development and function. Its deficiency has been shown to be linked with the emergence of neurological diseases. Dietary ω-3 fatty acid supplements including DHA have been suggested to improve neuronal development and enhance cognitive functions. Findings suggested that DHA is better incorporated into the brain when esterified at the sn-2 position of a lysophosphatidylcholine (LysoPC-DHA. AceDoPC® is a structured phospholipid or acetyl-LysoPC-DHA. As previously shown for LysoPC-DHA, AceDoPC® is a specific and preferred carrier of DHA to the brain. When AceDoPC® was injected to rats that were subjected to an ischemic stroke, it prevents the extension of brain lesions. Regarding the essential role of DHA for cerebral functions, targeting the brain with specific carriers of DHA might provide novel therapeutic approaches to neurodegenerative diseases.

Supplementing female rats with DHA-lysophosphatidylcholine increases docosahexaenoic acid and acetylcholine contents in the brain and improves the memory and learning capabilities of the pups

Energy Technology Data Exchange (ETDEWEB)

Valenzuela, A.; Nieto, S.; Sanhueza, J.; Morgado, N.; Rojas, I.; Zanartu, P.

2010-07-01

Docosahexaenoic acid (Dha) is supplied to the foetus and newborn through the mother from their own reserves and their diet. No consensus about the best form to supplement DHA has been established. We propose that DHA containing lysophosphatidylcholine (DHA-LPC), obtained from DHA-rich eggs may be a suitable form of DHA and choline (the precursor of acetylcholine) supplementation. We evaluated the effectiveness of DHA-LPC to increase DHA and acetylcholine concentration in the brain of pups born from female rats supplemented with DHA-LPC before and during pregnancy. We also evaluated the effect of DHA supplementation on learning and memory capabilities of pups through the Skinner test for operant conditioning. Female Wistar rats received 40-day supplementation of DHA-LPC (8 mg DHA/kg b.w/daily.), before and during pregnancy. After delivery, plasma, erythrocyte, liver, and adipose tissue DHA and plasma choline were analyzed. Brains from 60 day-old pups separated into frontal cortex, cerebellum, striatum, hippocampus, and occipital cortex, were assessed for DHA, acetylcholine, and acetylcholine transferase (CAT) activity. Pups were subjected to the Skinner box test. DHA-LPC supplementation produces higher choline and liver DHA contents in the mothers plasma and increases the pups DHA and acetylcholine in the cerebellum and hippocampus. CAT was not modified by supplementation. The Skinner test shows that pups born from DHA-LPC supplemented mothers exhibit better scores of learning and memory than the controls. Conclusion: DHA-LPC may be an adequate form for DHA supplementation during the perinatal period. (Author) 66 refs.

The Effects of Fenarimol and Methyl Parathion on Glucose 6-Phosphate Dehydrogenase Enzyme Activity in Rats

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Ferda ARI

2017-10-01

Full Text Available Fenarimol and methyl parathion are pesticides that have been used in agriculture for several years. These pesticides have significant effects on environmental and human health. Therefore, we investigated the effects of methyl parathion and fenarimol on glucose 6-phosphate dehydrogenase (EC 1.1.1.49 enzyme activity in rats. The glucose 6- phosphate dehydrogenase is the first enzyme of the pentose phosphate pathway and it is important in detoxifying reactions by NADPH generated. In this study, wistar albino rats administrated with methyl parathion (7 mg kg–1 and fenarimol (200 mg kg−1 by intraperitoneally for different periods (2, 4, 8, 16, 32, 64, and 72 h. The glucose 6-phosphate dehydrogenase enzyme activity was assayed in liver, kidney, brain, and small intestine in male and female rats. The exposure of fenarimol and methyl parathion caused increase of glucose 6-phosphate dehydrogenase enzyme activity in rat tissues, especially at last periods. We suggest that this increment of enzyme activity may be the reason of toxic effects of fenarimol and methyl parathion.

Breast milk docosahexaenoic acid (DHA) correlates with DHA status of malnourished infants

NARCIS (Netherlands)

Smit, EN; Oelen, EA; Seerat, E; Muskiet, FAJ; Boersma, ER

Aim-To investigate whether low docosahexaenoic acid (22:6 omega 3; DHA) status of malnourished, mostly breast fed infants is a result of low omega 3 fatty acid intake via breast milk. Methods-Fatty acid composition of breast milk of eight Pakistani mothers, and of the erythrocytes of their

Response of soil microbial activities and microbial community structure to vanadium stress.

Science.gov (United States)

Xiao, Xi-Yuan; Wang, Ming-Wei; Zhu, Hui-Wen; Guo, Zhao-Hui; Han, Xiao-Qing; Zeng, Peng

2017-08-01

High levels of vanadium (V) have long-term, hazardous impacts on soil ecosystems and biological processes. In the present study, the effects of V on soil enzymatic activities, basal respiration (BR), microbial biomass carbon (MBC), and the microbial community structure were investigated through 12-week greenhouse incubation experiments. The results showed that V content affected soil dehydrogenase activity (DHA), BR, and MBC, while urease activity (UA) was less sensitive to V stress. The average median effective concentration (EC 50 ) thresholds of V were predicted using a log-logistic dose-response model, and they were 362mgV/kg soil for BR and 417mgV/kg soil for DHA. BR and DHA were more sensitive to V addition and could be used as biological indicators for soil V pollution. According to a polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) analysis, the structural diversity of the microbial community decreased for soil V contents ranged between 254 and 1104mg/kg after 1 week of incubation. As the incubation time increased, the diversity of the soil microbial community structure increased for V contents ranged between 354 and 1104mg/kg, indicating that some new V-tolerant bacterial species might have replicated under these conditions. Copyright © 2017 Elsevier Inc. All rights reserved.

Biodegradace environmentálních polutantů - charakterizace mutantní halogenalkandehalogenasy DhaA31 z Rhodococcus rhodochrous NCIMB 13064

OpenAIRE

MALCHER, Pavel

2013-01-01

The project was focused on using of protein crystallography practically and mainly on preparation of crystals of model protein Thermolysin and haloalkan dehalogenase mutant variant DhaA31 with the use of standard and advanced crystallization methods. Later the DhaA31 structure was solved and graphically visualized using the molecular modeling programs as well as the structure of Thermolysin. Obtaining the crystals of both studied proteins and description of the DhaA31 structure, active site a...

Sources connues et potentielles de DHA pour les besoins de l’homme

Directory of Open Access Journals (Sweden)

Barnathan Gilles

2007-01-01

Full Text Available This paper focuses on the production of docosahexaenoic acid (DHA; 22:6 n-3, a major ω3 polyunsaturated fatty acid (PUFA with applications in foods and pharmaceuticals. Fish oils are currently the main source of PUFA including EPA and DHA. Growing interest in PUFA properties in various fields coupled with their significance in health and dietary requirements has encouraged searching for more suitable sources of these compounds, specially DHA. Some methods in lipid extracting process now allow to get a better industrial use for fish by-products. An important objective is to find cultivated microbiological sources that delivered DHA but no EPA. Potentialities of marine bacteria, microalgae and marine protists are described. The dinoflagellate Crypthecodinium cohnii seems the most efficient microrganism for the large-scale production of DHA devoid of EPA. The marine protists Thraustochytrids offer promising possibilities for DHA and other major PUFA production. C. cohnii as well as Thraustochytrium and Schizochytrium are able to produce large biomass and lipid amounts, and DHA at levels up to 60%. The first results in the production of n-3 long-chain PUFA in transgenic plants are given.

A dose response randomised controlled trial of docosahexaenoic acid (DHA) in preterm infants.

Science.gov (United States)

Collins, C T; Sullivan, T R; McPhee, A J; Stark, M J; Makrides, M; Gibson, R A

2015-08-01

Thirty one infants born less than 30 weeks׳ gestational age were randomised to receive either 40 (n=11), 80 (n=9) or 120 (n=11) mg/kg/day of docosahexaenoic acid (DHA) respectively as an emulsion, via the feeding tube, commenced within 4 days of the first enteral feed. Twenty three infants were enroled in non-randomised reference groups; n=11 who had no supplementary DHA and n=12 who had maternal DHA supplementation. All levels of DHA in the emulsion were well tolerated with no effect on number of days of interrupted feeds or days to full enteral feeds. DHA levels in diets were directly related to blood DHA levels but were unrelated to arachidonic acid (AA) levels. All randomised groups and the maternal supplementation reference group prevented the drop in DHA levels at study end that was evident in infants not receiving supplementation. Australian New Zealand Clinical Trials Registry: ACTRN12610000382077. Copyright © 2015 Elsevier Ltd. All rights reserved.

Screening of new British thraustochytrids isolates for docosahexaenoic acid (DHA) production.

Science.gov (United States)

Marchan, Loris Fossier; Lee Chang, Kim J; Nichols, Peter D; Polglase, Jane L; Mitchell, Wilfrid J; Gutierrez, Tony

2017-01-01

Thraustochytrids isolated from hot tropical and sub-tropical waters have been well studied for DHA and biodiesel production in the last decades. However, little research has been performed on the oils of cold water thraustochytrids, in particular from the North Sea region. In this study, thraustochytrid strains from British waters showed high relative levels of omega-3 long-chain (≥C 20 ) polyunsaturated fatty acids (LC-PUFA), including docosahexaenoic acid (DHA, 22:6ω3). The relative levels of DHA (as % of total fatty acids, TFA) in the different British strains are hitherto amongst the highest recorded from any thraustochytrid screening study, with strain TL18 reaching up to 67% DHA in modified Glucose-Yeast Extract-Peptone (GYP) medium. At this screening stage, low final biomass and fatty acid yield were observed in modified GYP and MarChiquita-Brain Heart Broth (MCBHB), while PUFA profiles (as % of PUFA) remained unaltered regardless of the culture medium used. Hence, optimizing the medium and culture conditions to improve growth and lipid content, without impacting the relative percentage of DHA, has the potential to increase the final DHA concentration. With this in mind, three strains were identified as promising organisms for the production of DHA. In the context of possible future industrial exploitation involving a winterization step, we investigated the recycling of the residual oil for biodiesel use. To do this, a mathematical model was used to assess the intrinsic properties of the by-product oil. The results showed the feasibility of producing primary DHA-rich oil, assuming optimized conditions, while using the by-product oil for biodiesel use.

Fecal hydroxysteroid dehydrogenase activities in vegetarian Seventh-Day Adventists, control subjects, and bowel cancer patients.

Science.gov (United States)

Macdonald, I A; Webb, G R; Mahony, D E

1978-10-01

Cell-free extracts were prepared from mixed fecal anaerobic bacteria grown from stools of 14 vegetarian Seventh-Day Adventists, 16 omnivorous control subjects, and eight patients recently diagnosed with cancer of the large bowel. Preparations were assayed for NAD- and NADP-dependent 3alpha-, 7alpha- and 12alpha-hydroxysteroid dehydrogenases with bile salts and androsterone as substrates (eight substrate-cofactor combinations were tested). A significant intergroup difference was observed in the amounts of NAD- and NADP-dependent 7alpha-hydroxysteroid dehydrogenase produced: bowel cancer patients exceeded controls, and controls exceeded Seventh-Day Adventists. Other enzyme activity comparisons were not significant. The pH values of the stools were significantly higher in cancer patients compared to Seventh-Day Adventists; values were 7.03 +/- 0.60 and 6.46 +/- 0.58 respectively. The pH value for controls was 6.66 +/- 0.62. A plot of pH value versus NADP-dependent 7alpha-hydroxysteroid dehydrogenase tended to separate the cancer patients from the other groups. Comparative data suggest that much of the 3alpha-hydroxysteroid dehydrogenase active against bile salt is also active against androsterone.

Inhibition effects of furfural on alcohol dehydrogenase, aldehyde dehydrogenase and pyruvate dehydrogenase.

Science.gov (United States)

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

Randomized Controlled Trial of DHA Supplementation during Pregnancy: Child Adiposity Outcomes

Science.gov (United States)

Foster, Byron A.; Escaname, Elia; Powell, Theresa L.; Larsen, Benjamin; Siddiqui, Sartaj K.; Menchaca, John; Aquino, Christian; Ramamurthy, Rajam; Hale, Daniel E.

2017-01-01

Investigating safe and effective interventions in pregnancy that lower offspring adiposity is important given the burden of obesity and subsequent metabolic derangements. Our objective was to determine if docosahexaenoic acid (DHA) given during pregnancy to obese mothers results in lower offspring adiposity. This study was a long-term follow-up of a randomized trial of mothers with gestational diabetes or obesity who were randomized to receive DHA supplementation at 800 mg/day or placebo (corn/soy oil) starting at 25–29 weeks gestation. Anthropometric measures were collected at birth and maternal erythrocyte DHA and arachidonic (AA) levels were measured at 26 and 36 weeks gestation. At two- and four-year follow-up time points, offspring adiposity measures along with a diet recall were assessed. A significant increase in erythrocyte DHA levels was observed at 36 weeks gestation in the supplemented group (p < 0.001). While no significant differences by measures of adiposity were noted at birth, two or four years by randomization group, duration of breastfeeding (p < 0.001), and DHA level at 36 weeks (p = 0.002) were associated with body mass index z-score. Our data suggest that DHA supplementation during pregnancy in obese mothers may have long-lasting effects on offspring measures of adiposity. PMID:28574453

Efficient production of triacylglycerols rich in docosahexaenoic acid (DHA) by osmo-heterotrophic marine protists.

Science.gov (United States)

Liu, Ying; Tang, Jie; Li, Jingjing; Daroch, Maurycy; Cheng, Jay J

2014-12-01

Thraustochytrids have recently emerged as a promising source for docosahexaenoic acid (DHA) production due to their high growth rate and oil content. In this study, two thraustochytrid isolates, Aurantiochytrium sp. PKU#SW7 and Thraustochytriidae sp. PKU#Mn16 were used for DHA production. Following growth parameters were optimized to maximize DHA production: temperature, pH, salinity, and glucose concentration. Both isolates achieved the highest DHA yield at the cultivation temperature of 28 °C, pH 6, 100 % seawater, and 2 % glucose. A DHA yield of 1.395 g/l and 1.426 g/l was achieved under the optimized culture conditions. Further investigation revealed that both isolates possess simple fatty acids profiles with palmitic acid and DHA as their dominant constituents, accounting for ∼79 % of total fatty acids. To date, very few studies have focused on the DHA distribution in various lipid fractions which is an important factor for identifying strains with a potential for industrial DHA production. In the present study, the lipids profiles of each strain both revealed that the majority of DHA was distributed in neutral lipids (NLs), and the DHA distribution in NLs of PKU#SW7 was exclusively in the form of triacylglycerols (TAGs) which suggest that PKU#SW7 could be utilized as an alternative source of DHA for dietary supplements. The fermentation process established for both strains also indicating that Aurantiochytrium sp. PKU#SW7 was more suitable for cultivation in fermenter. In addition, the high percentage of saturated fatty acids produced by the two thraustochytrids indicates their potential application in biodiesel production. Overall, our findings suggest that two thraustochytrid isolates are suitable candidates for biotechnological applications.

Production of lipids and docosahexasaenoic acid (DHA) by a native Thraustochytrium strain

DEFF Research Database (Denmark)

Shene, Carolina; Leyton, Allison; Rubilar, Mónica

2013-01-01

/w. Under this growth condition lipids and DHA productivities were 50 and 23 mg/(L h), respectively. Practical applications: Consumption of long chain‐polyunsaturated fatty acids (LC‐PUFA) belonging to the omega‐3 family such as DHA has several positive effects on human and animal health. However, natural...... sources are restricted to cold‐water fish and their oils. Marine protists are also good candidates for the production of microbial DHA. For evaluating the potential of new strains the effect of the growth medium composition, growth conditions, and cultivation mode on DHA productivity has to be determined...

Addition of DHA synergistically enhances the efficacy of regorafenib for kidney cancer therapy

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Kim, Jeffrey; Ulu, Arzu; Wan, Debin; Yang, Jun; Hammock, Bruce D; Weiss, Robert H.

2016-01-01

Kidney cancer is the 6th most common cancer in the US and its incidence is increasing. The treatment of this malignancy took a major step forward with the recent introduction of targeted therapeutics such as the kinase inhibitors. Unfortunately, kinase inhibition is associated with the onset of resistance after 1–2 years of treatment. Regorafenib, like many multi-kinase inhibitors, was designed to block the activities of several key kinase pathways involved in oncogenesis (Ras/Raf/MEK/ERK) and tumor angiogenesis (VEGF-receptors), and we have recently shown that it also possesses soluble epoxide hydrolase (sEH) inhibitory activity which may be contributing to its salutary effects in patients. Since sEH inhibition results in increases in the DHA-derived epoxydocosapentaenoic acids (EDPs) which we have previously described to possess anti-cancer properties, we asked whether the addition of DHA to a therapeutic regimen in the presence of regorafenib would enhance its beneficial effects in vivo. We now show that the combination of regorafenib and DHA results in a synergistic effect upon tumor invasiveness as well as p-VEGFR attenuation. In addition, this combination showed a reduction in tumor weights, greater than each agent alone, in a mouse xenograft model of human RCC, yielding the expected oxylipin profiles; this data was supported in several RCC cell lines which showed similar results in vitro. Since DHA is the predominant component of fish oil, our data suggest that this non-toxic dietary supplement could be administered with regorafenib during therapy for advanced RCC and could be the basis of a clinical trial. PMID:26921392

Effects of the polyunsaturated fatty acids, EPA and DHA, on hematological malignancies: a systematic review.

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Moloudizargari, Milad; Mortaz, Esmaeil; Asghari, Mohammad Hossein; Adcock, Ian M; Redegeld, Frank A; Garssen, Johan

2018-02-20

Omega-3 polyunsaturated fatty acids (PUFAs) have well established anti-cancer properties. Eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) are among this biologically active family of macromolecules for which various anti-cancer effects have been explained. These PUFAs have a high safety profile and can induce apoptosis and inhibit growth of cancer cells both in vitro and in vivo , following a partially selective manner. They also increase the efficacy of chemotherapeutic agents by increasing the sensitivity of different cell lines to specific anti-neoplastic drugs. Various mechanisms have been proposed for the anti-cancer effects of these omega-3 PUFAs; however, the exact mechanisms still remain unknown. While numerous studies have investigated the effects of DHA and EPA on solid tumors and the responsible mechanisms, there is no consensus regarding the effects and mechanisms of action of these two FAs in hematological malignancies. Here, we performed a systematic review of the beneficial effects of EPA and DHA on hematological cell lines as well as the findings of related in vivo studies and clinical trials. We summarize the key underlying mechanisms and the therapeutic potential of these PUFAs in the treatment of hematological cancers. Differential expression of apoptosis-regulating genes and Glutathione peroxidase 4 (Gp-x4), varying abilities of different cancerous and healthy cells to metabolize EPA into its more active metabolites and to uptake PUFAS are among the major factors that determine the sensitivity of cells to DHA and EPA. Considering the abundance of data on the safety of these FAs and their proven anti-cancer effects in hematological cell lines and the lack of related human studies, further research is warranted to find ways of exploiting the anticancer effects of DHA and EPA in clinical settings both in isolation and in combination with other therapeutic regimens.

Impact of Genotype on EPA and DHA Status and Responsiveness to Increased Intakes

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Anne Marie Minihane

2016-03-01

Full Text Available At a population level, cardioprotective and cognitive actions of the fish oil (FO derived long-chain n-3 polyunsaturated fatty acids (LC n-3 PUFAs eicosapentaenoic acid (EPA and docosahexaenoic acid (DHA have been extensively demonstrated. In addition to dietary intake, which is limited for many individuals, EPA and DHA status is dependent on the efficiency of their biosynthesis from α-linolenic acid. Gender and common gene variants have been identified as influencing the rate-limiting desaturase and elongase enzymes. Response to a particular intake or status is also highly heterogeneous and likely influenced by genetic variants which impact on EPA and DHA metabolism and tissue partitioning, transcription factor activity, or physiological end-point regulation. Here, available literature relating genotype to tissue LC n-3 PUFA status and response to FO intervention is considered. It is concluded that the available evidence is relatively limited, with much of the variability unexplained, though APOE and FADS genotypes are emerging as being important. Although genotype × LC n-3 PUFA interactions have been described for a number of phenotypes, few have been confirmed in independent studies. A more comprehensive understanding of the genetic, physiological and behavioural modulators of EPA and DHA status and response to intervention is needed to allow refinement of current dietary LC n-3 PUFA recommendations and stratification of advice to “vulnerable” and responsive subgroups.

Impact of DHA on Metabolic Diseases from Womb to Tomb

NARCIS (Netherlands)

Arnoldussen, I.A.C.; Kiliaan, A.J.

2014-01-01

Long chain polyunsaturated fatty acids (LC-PUFAs) are important mediators in improving and maintaining human health over the total lifespan. One topic we especially focus on in this review is omega-3 LC-PUFA docosahexaenoic acid (DHA). Adequate DHA levels are essential during neurodevelopment and,

Comparative Analysis of EPA/DHA-PL Forage and Liposomes in Orotic Acid-Induced Nonalcoholic Fatty Liver Rats and Their Related Mechanisms.

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Chang, Mengru; Zhang, Tiantian; Han, Xiuqing; Tang, Qingjuan; Yanagita, Teruyoshi; Xu, Jie; Xue, Changhu; Wang, Yuming

2018-02-14

Nonalcoholic fatty liver disease (NAFLD) has become one predictive factor of death from various illnesses. The present study was to comparatively investigate the effects of eicosapentaenoic acid-enriched and docosahexaenoic acid-enriched phospholipids forage (EPA-PL and DHA-PL) and liposomes (lipo-EPA and lipo-DHA) on NAFLD and demonstrate the possible protective mechanisms involved. The additive doses of EPA-PL and DHA-PL in all treatment groups were 1% of total diets, respectively. The results showed that Lipo-EPA could significantly improve hepatic function by down-regulating orotic acid-induced serum aspartate aminotransferase (AST) and alanine aminotransferase (ALT) levels by 55.6% and 34.2%, respectively (p DHA could also significantly suppress hepatic lipid accumulation mainly by enhancement of hepatic lipolysis and cholesterol efflux. Furthermore, DHA-PL played a certain role in inhibiting hepatic lipogenesis and accelerating cholesterol efflux. The results obtained in this work might contribute to the understanding of the biological activities of EPA/DHA-PL and liposomes and further investigation on its potential application values for food supplements.

DHA but Not EPA Emulsions Preserve Neurological and Mitochondrial Function after Brain Hypoxia-Ischemia in Neonatal Mice.

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Mayurasakorn, Korapat; Niatsetskaya, Zoya V; Sosunov, Sergey A; Williams, Jill J; Zirpoli, Hylde; Vlasakov, Iliyan; Deckelbaum, Richard J; Ten, Vadim S

2016-01-01

Treatment with triglyceride emulsions of docosahexaenoic acid (tri-DHA) protected neonatal mice against hypoxia-ischemia (HI) brain injury. The mechanism of this neuroprotection remains unclear. We hypothesized that administration of tri-DHA enriches HI-brains with DHA/DHA metabolites. This reduces Ca2+-induced mitochondrial membrane permeabilization and attenuates brain injury. 10-day-old C57BL/6J mice following HI-brain injury received tri-DHA, tri-EPA or vehicle. At 4-5 hours of reperfusion, mitochondrial fatty acid composition and Ca2+ buffering capacity were analyzed. At 24 hours and at 8-9 weeks of recovery, oxidative injury, neurofunctional and neuropathological outcomes were evaluated. In vitro, hyperoxia-induced mitochondrial generation of reactive oxygen species (ROS) and Ca2+ buffering capacity were measured in the presence or absence of DHA or EPA. Only post-treatment with tri-DHA reduced oxidative damage and improved short- and long-term neurological outcomes. This was associated with increased content of DHA in brain mitochondria and DHA-derived bioactive metabolites in cerebral tissue. After tri-DHA administration HI mitochondria were resistant to Ca2+-induced membrane permeabilization. In vitro, hyperoxia increased mitochondrial ROS production and reduced Ca2+ buffering capacity; DHA, but not EPA, significantly attenuated these effects of hyperoxia. Post-treatment with tri-DHA resulted in significant accumulation of DHA and DHA derived bioactive metabolites in the HI-brain. This was associated with improved mitochondrial tolerance to Ca2+-induced permeabilization, reduced oxidative brain injury and permanent neuroprotection. Interaction of DHA with mitochondria alters ROS release and improves Ca2+ buffering capacity. This may account for neuroprotective action of post-HI administration of tri-DHA.

DHA but Not EPA Emulsions Preserve Neurological and Mitochondrial Function after Brain Hypoxia-Ischemia in Neonatal Mice.

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Korapat Mayurasakorn

Full Text Available Treatment with triglyceride emulsions of docosahexaenoic acid (tri-DHA protected neonatal mice against hypoxia-ischemia (HI brain injury. The mechanism of this neuroprotection remains unclear. We hypothesized that administration of tri-DHA enriches HI-brains with DHA/DHA metabolites. This reduces Ca2+-induced mitochondrial membrane permeabilization and attenuates brain injury.10-day-old C57BL/6J mice following HI-brain injury received tri-DHA, tri-EPA or vehicle. At 4-5 hours of reperfusion, mitochondrial fatty acid composition and Ca2+ buffering capacity were analyzed. At 24 hours and at 8-9 weeks of recovery, oxidative injury, neurofunctional and neuropathological outcomes were evaluated. In vitro, hyperoxia-induced mitochondrial generation of reactive oxygen species (ROS and Ca2+ buffering capacity were measured in the presence or absence of DHA or EPA.Only post-treatment with tri-DHA reduced oxidative damage and improved short- and long-term neurological outcomes. This was associated with increased content of DHA in brain mitochondria and DHA-derived bioactive metabolites in cerebral tissue. After tri-DHA administration HI mitochondria were resistant to Ca2+-induced membrane permeabilization. In vitro, hyperoxia increased mitochondrial ROS production and reduced Ca2+ buffering capacity; DHA, but not EPA, significantly attenuated these effects of hyperoxia.Post-treatment with tri-DHA resulted in significant accumulation of DHA and DHA derived bioactive metabolites in the HI-brain. This was associated with improved mitochondrial tolerance to Ca2+-induced permeabilization, reduced oxidative brain injury and permanent neuroprotection. Interaction of DHA with mitochondria alters ROS release and improves Ca2+ buffering capacity. This may account for neuroprotective action of post-HI administration of tri-DHA.

Growth hormone-induced insulin resistance in human subjects involves reduced pyruvate dehydrogenase activity

DEFF Research Database (Denmark)

Nellemann, B.; Vendelbo, M.H.; Nielsen, Thomas Svava

2014-01-01

Insulin resistance induced by growth hormone (GH) is linked to promotion of lipolysis by unknown mechanisms. We hypothesized that suppression of the activity of pyruvate dehydrogenase in the active form (PDHa) underlies GH-induced insulin resistance similar to what is observed during fasting....

The activity of dehydrogenases in the uterus of C57B mice after X-irradiation and serotonin treatment

International Nuclear Information System (INIS)

Mazur, L.

1978-01-01

In C57B female mice, irradiated with 500 R and/or treated with serotonin (5-hydroxytryptamine), the activity of dehydrogenases in the uterus was studied on the fourth day of pregnancy. The reduction of 2,3,5-triphenyltetrazolium chloride to formazane by the uterine tissue was taken as the measure of such activity. The activity of dehydrogenases in the uterus of irradiated mice was distinctly lower than in non-irradiated controls. This activity was also depressed after serotonin treatment, the level of enzyme activity being dose-dependent. In females injected with serotonin and then irradiated, the activity of dehydrogenases was higher than in those irradiated only. The radioprotective effect was more pronounced in mice injected with serotonin alone on the third day of pregnancy i.e. shortly before irradiation, than in those injected on the second and the third day. (author)

[Effects of Light Near-Infrared Radiation on Rats Assessed by Succinate Dehydrogenase Activity in Lymphocytes on Blood Smears].

Science.gov (United States)

Khunderyakova, N V; Zakharchenko, A V; Zakharchenko, M V; Muller, H; Fedotcheva, I; Kondrashova, M N

2015-01-01

Biological effects of light near infrared radiation (850 nm), with modulation acoustic frequency of 101 Hz, was studied. The study was conducted on rats, the effect was recorded by succinate dehydrogenase activity in lymphocytes on the blood smear after administration of the activating dose of adrenaline, which simulates the state of the organism in the early stages of the pathogenic effects (stress). A pronounced regulating effect of infrared radiation on the activity of succinate dehydrogenase in animals activated by adrenaline was shown. Infrared radiation has a normalizing effect reducing the degree of inhibition or activation of the enzyme induced by adrenaline and had no effect on the control animals. Thus, by modulating the activity of succinate dehydrogenase infrared radiation regulates energy production in the mitochondria supported by the most powerful oxidation substrate--succinic acid, which is especially pronounced under stress.

DHA but Not EPA Emulsions Preserve Neurological and Mitochondrial Function after Brain Hypoxia-Ischemia in Neonatal Mice

Science.gov (United States)

Sosunov, Sergey A.; Williams, Jill J.; Zirpoli, Hylde; Vlasakov, Iliyan; Deckelbaum, Richard J.; Ten, Vadim S.

2016-01-01

Background and Purpose Treatment with triglyceride emulsions of docosahexaenoic acid (tri-DHA) protected neonatal mice against hypoxia-ischemia (HI) brain injury. The mechanism of this neuroprotection remains unclear. We hypothesized that administration of tri-DHA enriches HI-brains with DHA/DHA metabolites. This reduces Ca2+-induced mitochondrial membrane permeabilization and attenuates brain injury. Methods 10-day-old C57BL/6J mice following HI-brain injury received tri-DHA, tri-EPA or vehicle. At 4–5 hours of reperfusion, mitochondrial fatty acid composition and Ca2+ buffering capacity were analyzed. At 24 hours and at 8–9 weeks of recovery, oxidative injury, neurofunctional and neuropathological outcomes were evaluated. In vitro, hyperoxia-induced mitochondrial generation of reactive oxygen species (ROS) and Ca2+ buffering capacity were measured in the presence or absence of DHA or EPA. Results Only post-treatment with tri-DHA reduced oxidative damage and improved short- and long-term neurological outcomes. This was associated with increased content of DHA in brain mitochondria and DHA-derived bioactive metabolites in cerebral tissue. After tri-DHA administration HI mitochondria were resistant to Ca2+-induced membrane permeabilization. In vitro, hyperoxia increased mitochondrial ROS production and reduced Ca2+ buffering capacity; DHA, but not EPA, significantly attenuated these effects of hyperoxia. Conclusions Post-treatment with tri-DHA resulted in significant accumulation of DHA and DHA derived bioactive metabolites in the HI-brain. This was associated with improved mitochondrial tolerance to Ca2+-induced permeabilization, reduced oxidative brain injury and permanent neuroprotection. Interaction of DHA with mitochondria alters ROS release and improves Ca2+ buffering capacity. This may account for neuroprotective action of post-HI administration of tri-DHA. PMID:27513579

Changes in cinnamyl alcohol dehydrogenase activities from sugarcane cultivars inoculated with Sporisorium scitamineum sporidia.

Science.gov (United States)

Santiago, Rocío; Alarcón, Borja; de Armas, Roberto; Vicente, Carlos; Legaz, María Estrella

2012-06-01

This study describes a method for determining cinnamyl alcohol dehydrogenase activity in sugarcane stems using reverse phase (RP) high-performance liquid chromatography to elucidate their possible lignin origin. Activity is assayed using the reverse mode, the oxidation of hydroxycinnamyl alcohols into hydroxycinnamyl aldehydes. Appearance of the reaction products, coniferaldehyde and sinapaldehyde is determined by measuring absorbance at 340 and 345 nm, respectively. Disappearance of substrates, coniferyl alcohol and sinapyl alcohol is measured at 263 and 273 nm, respectively. Isocratic elution with acetonitrile:acetic acid through an RP Mediterranea sea C18 column is performed. As case examples, we have examined two different cultivars of sugarcane; My 5514 is resistant to smut, whereas B 42231 is susceptible to the pathogen. Inoculation of sugarcane stems elicits lignification and produces significant increases of coniferyl alcohol dehydrogenase (CAD) and sinapyl alcohol dehydrogenase (SAD). Production of lignin increases about 29% in the resistant cultivar and only 13% in the susceptible cultivar after inoculation compared to uninoculated plants. Our results show that the resistance of My 5514 to smut is likely derived, at least in part, to a marked increase of lignin concentration by the activation of CAD and SAD. Copyright © Physiologia Plantarum 2012.

Posttranslational regulation of glucose-6-phosphate dehydrogenase activity in tongue epithelium

NARCIS (Netherlands)

Biagiotti, E.; Bosch, K. S.; Ninfali, P.; Frederiks, W. M.; van Noorden, C. J.

2000-01-01

Expression of glucose-6-phosphate dehydrogenase (G6PD) activity is high in tongue epithelium, but its exact function is still unknown, it may be related;either to the high proliferation rate of this tissue or to protection against oxidative stress. To elucidate its exact role, we localized

Influence of thorax irradiation on lactic dehydrogenase isoenzyme activity

International Nuclear Information System (INIS)

Valle, C.; Munnich, A.; Pasquier, C.

The right hemi-thorax of rats was irradiated with 1200 and 3000 rads ( 60 Co) and blood samples were taken sequentially. The five lactic dehydrogenase (LDH) isoenzymes which have proved to be useful as biochemical indicators of acute pulmonary injury in other experimental animals (dogs), were assayed, after irradiation, as a function of time and as a functon of dose. There was no significant change in LDH isoenzyme activities after lung irradiation in rats [fr

Supplementing female rats with DHA-lysophosphatidylcholine increases docosahexaenoic acid and acetylcholine contents in the brain and improves the memory and learning capabilities of the pups.

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Rojas, I.

2010-03-01

Full Text Available Docosahexaenoic acid (DHA is supplied to the foetus and newborn through the mother from their own reserves and their diet. No consensus about the best form to supplement DHA has been established. We propose that DHAcontaining lysophosphatidylcholine (DHA-LPC, obtained from DHA-rich eggs may be a suitable form of DHA and choline (the precursor of acetylcholine supplementation. We evaluated the effectiveness of DHA-LPC to increase DHA and acetylcholine concentration in the brain of pups born from female rats supplemented with DHA-LPC before and during pregnancy. We also evaluated the effect of DHA supplementation on learning and memory capabilities of pups through the Skinner test for operant conditioning. Female Wistar rats received 40-day supplementation of DHA-LPC (8 mg DHA/kg b.w/daily., before and during pregnancy. After delivery, plasma, erythrocyte, liver, and adipose tissue DHA and plasma choline were analyzed. Brains from 60 day-old pups separated into frontal cortex, cerebellum, striatum, hippocampus, and occipital cortex, were assessed for DHA, acetylcholine, and acetylcholine transferase (CAT activity. Pups were subjected to the Skinner box test. DHA-LPC supplementation produces higher choline and liver DHA contents in the mother’s plasma and increases the pups’ DHA and acetylcholine in the cerebellum and hippocampus. CAT was not modified by supplementation. The Skinner test shows that pups born from DHA-LPC supplemented mothers exhibit better scores of learning and memory than the controls. Conclusion: DHA-LPC may be an adequate form for DHA supplementation during the perinatal period.El ácido docosahexaenoico (DHA que requiere el feto y el recién nacido lo aporta la madre desde sus reservas y la dieta, por lo cual se sugiere suplementar a la madre con DHA. No hay consenso sobre la mejor forma de suplementación. Proponemos que un lisofosfolípido que contiene DHA y colina (DHA-LPC obtenido de huevos con alto contenido de DHA es

21 CFR 862.1670 - Sorbitol dehydrogenase test system.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Sorbitol dehydrogenase test system. 862.1670... Systems § 862.1670 Sorbitol dehydrogenase test system. (a) Identification. A sorbitol dehydrogenase test system is a device intended to measure the activity of the enzyme sorbitol dehydrogenase in serum...

Eicosapentaenoic acid (EPA) vs. Docosahexaenoic acid (DHA): Effects in epididymal white adipose tissue of mice fed a high-fructose diet.

Science.gov (United States)

Bargut, Thereza Cristina Lonzetti; Santos, Larissa Pereira; Machado, Daiana Guimarães Lopes; Aguila, Marcia Barbosa; Mandarim-de-Lacerda, Carlos Alberto

2017-08-01

Eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) have been demonstrated to be beneficial for many diseases, including those associated with the metabolic syndrome (e.g. insulin resistance and hypertension). Nevertheless, not only their actions are not entirely understood, but also their only effects were not yet elucidated. Therefore, we aimed to compare the effects of EPA and DHA, alone or in combination, on the epididymal white adipose tissue (WAT) metabolism in mice fed a high-fructose diet. 3-mo-old C57Bl/6 mice were fed a control diet (C) or a high-fructose diet (HFru). After three weeks on the diets, the HFru group was subdivided into four new groups for another five weeks: HFru, HFru+EPA, HFru+DHA, and HFru-EPA+DHA (n=10/group). Besides evaluating biometric and metabolic parameters of the animals, we measured the adipocyte area and performed molecular analyses (inflammation and lipolysis) in the epididymal WAT. The HFru group showed adipocyte hypertrophy, inflammation, and uncontrolled lipolysis. The treated animals showed a reversion of adipocyte hypertrophy, inhibition of inflammation with activation of anti-inflammatory mediators, and regularization of lipolysis. Overall, the beneficial effects were more marked with DHA than EPA. Although the whole-body metabolic effects were similar between EPA and DHA, DHA appeared to be the central actor in WAT metabolism, modulating pro and anti-inflammatory pathways and alleviating adipocytes abnormalities. Therefore, when considering fructose-induced adverse effects in WAT, the most prominent actions were observed with DHA. Copyright © 2017 Elsevier Ltd. All rights reserved.

Glucose-6-phosphate dehydrogenase activity decreases during storage of leukoreduced red blood cells

NARCIS (Netherlands)

Peters, Anna L.; van Bruggen, Robin; de Korte, Dirk; van Noorden, Cornelis J. F.; Vlaar, Alexander P. J.

2016-01-01

During storage, the activity of the red blood cell (RBC) antioxidant system decreases. Glucose-6-phosphate dehydrogenase (G6PD) is essential for protection against oxidative stress by producing NADPH. G6PD function of RBC transfusion products is reported to remain stable during storage, but activity

Aggregation of Aß(25-35 on DOPC and DOPC/DHA bilayers: an atomic force microscopy study.

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Matilde Sublimi Saponetti

Full Text Available β amyloid peptide plays an important role in both the manifestation and progression of Alzheimer disease. It has a tendency to aggregate, forming low-molecular weight soluble oligomers, higher-molecular weight protofibrillar oligomers and insoluble fibrils. The relative importance of these single oligomeric-polymeric species, in relation to the morbidity of the disease, is currently being debated. Here we present an Atomic Force Microscopy (AFM study of Aβ(25-35 aggregation on hydrophobic dioleoylphosphatidylcholine (DOPC and DOPC/docosahexaenoic 22∶6 acid (DHA lipid bilayers. Aβ(25-35 is the smallest fragment retaining the biological activity of the full-length peptide, whereas DOPC and DOPC/DHA lipid bilayers were selected as models of cell-membrane environments characterized by different fluidity. Our results provide evidence that in hydrophobic DOPC and DOPC/DHA lipid bilayers, Aβ(25-35 forms layered aggregates composed of mainly annular structures. The mutual interaction between annular structures and lipid surfaces end-results into a membrane solubilization. The presence of DHA as a membrane-fluidizing agent is essential to protect the membrane from damage caused by interactions with peptide aggregates; to reduces the bilayer defects where the delipidation process starts.

Different dietary omega-3 sources during pregnancy and DHA in the developing rat brain

Directory of Open Access Journals (Sweden)

Childs Caroline E.

2011-09-01

Full Text Available The essential n-3 fatty acid α-linolenic acid (ALA can be converted into eicosapentaenoic acid (EPA, docosapentaenoic acid (DPA and docosahexaenoic acid (DHA under the action of desaturase and elongase enzymes. Human studies have demonstrated that females convert a higher proportion of ALA into EPA and DHA than males. We have demonstrated that when fed upon an ALA rich diet, female rats have a significantly higher EPA content of plasma and liver lipids than males. When fetal tissues were collected, it was observed that pups from dams fed the ALA rich diet had a comparable brain DHA status to those from dams fed on a salmon-oil based diet, indicating that conversion of ALA to DHA during pregnancy was efficient, and that DHA accumulated in a tissue-specific manner. Similar efficacy of dietary ALA in women during pregnancy would mean that plant n-3 fatty acids would be useful alternatives to preformed EPA and DHA.

EPA and DHA in blood cell membranes from acute coronary syndrome patients and controls.

Science.gov (United States)

Block, Robert C; Harris, William S; Reid, Kimberly J; Sands, Scott A; Spertus, John A

2008-04-01

Increased blood levels of the omega-3 fatty acids (FA) eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) have been inversely associated with risk for sudden cardiac death, but their relationship with acute coronary syndromes (ACS) is unclear. We hypothesized that the EPA+DHA content of blood cell membranes, as a percent of total FAs, is reduced in ACS patients relative to matched controls. We measured the content of EPA+DHA in 768 ACS patients and 768 age-, sex- and race-matched controls. The association with ACS case status of blood cell EPA+DHA [both by a 1 unit change and by category (low, or =8%)] was assessed using multivariate conditional logistic regression models adjusting for matching variables and smoking status, alcohol use, diabetes, body mass index, serum lipids, education, family history of coronary artery disease, personal histories of myocardial infarction and hypertension, and statin, aspirin, and other antiplatelet drug use. The combined groups had a mean age of 61+/-12 years, 66% were male, and 92% were Caucasian. The EPA+DHA content was 20% lower in cases than controls (3.4+/-1.6 vs. 4.25+/-2.0%, pACS event was 0.58 (95% CI 0.42-0.80), in the intermediate EPA+DHA group and was 0.31 (95% CI 0.14-0.67; p for trend ACS case status increased incrementally as the EPA+DHA content decreased suggesting that low EPA+DHA may be associated with increased risk for ACS.

Enhancement of Schizochytrium DHA synthesis by plasma mutagenesis aided with malonic acid and zeocin screening.

Science.gov (United States)

Zhao, Ben; Li, Yafei; Li, Changling; Yang, Hailin; Wang, Wu

2018-03-01

Schizochytrium sp. accumulates valuable polyunsaturated fatty acid (PUFA), such as docosahexaenoic acid (DHA). In order to increase DHA synthesis in this microorganism, physical or chemical mutagenesis aided with powerful screening methods are still preferable, as its DHA synthetic pathway has not yet been clearly defined for gene manipulation. To breed this agglomerate microorganism of thick cell wall and rather large genome for increasing lipid content and DHA percentage, a novel strategy of atmospheric and room temperature plasma (ARTP) mutagenesis coupled with stepped malonic acid (MA) and zeocin resistance screening was developed. The final resulted mutant strain mz-17 was selected with 1.8-fold increased DHA production. Accompanied with supplementation of Fe 2+ in shake flask cultivation, DHA production of 14.0 g/L on average was achieved. This work suggests that ARTP mutation combined with stepped MA and zeocin resistance screening is an efficient method of breeding Schizochytrium sp. of high DHA production, and might be applied on other microorganisms for obtaining higher desired PUFA products.

Dihydroartemisinin protects against alcoholic liver injury through alleviating hepatocyte steatosis in a farnesoid X receptor-dependent manner

Energy Technology Data Exchange (ETDEWEB)

Xu, Wenxuan; Lu, Chunfeng; Yao, Lu; Zhang, Feng; Shao, Jiangjuan [Department of Pharmacology, School of Pharmacy, Nanjing University of Chinese Medicine, Nanjing, Jiangsu Province (China); Zheng, Shizhong, E-mail: nytws@163.com [Department of Pharmacology, School of Pharmacy, Nanjing University of Chinese Medicine, Nanjing, Jiangsu Province (China); Jiangsu Key Laboratory for Pharmacology and Safety Evaluation of Chinese Materia Medica, Nanjing University of Chinese Medicine, Nanjing, Jiangsu Province (China)

2017-01-15

Alcoholic liver disease (ALD) is a common etiology of liver diseases, characterized by hepatic steatosis. We previously identified farnesoid X receptor (FXR) as a potential therapeutic target for ALD. Dihydroartemisinin (DHA) has been recently identified to possess potent pharmacological activities on liver diseases. This study was aimed to explore the impact of DHA on ALD and further elaborate the underlying mechanisms. Gain- or loss-of-function analyses of FXR were applied in both in vivo and in vitro studies. Results demonstrated that DHA rescued FXR expression and activity in alcoholic rat livers. DHA also reduced serodiagnostic markers of liver injury, including aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase, and lactate dehydrogenase. DHA improved alcohol-induced liver histological lesions, expression of inflammation genes, and inflammatory cell infiltration. In addition, DHA not only attenuated hyperlipidemia but also reduced hepatic steatosis through regulating lipogenesis and lipolysis genes. In vitro experiments further consolidated the concept that DHA ameliorated ethanol-caused hepatocyte injury and steatosis. Noteworthily, DHA effects were reinforced by FXR agonist obeticholic acid or FXR expression plasmids but abrogated by FXR antagonist Z-guggulsterone or FXR siRNA. In summary, DHA significantly improved alcoholic liver injury by inhibiting hepatic steatosis, which was dependent on its activation of FXR in hepatocytes. - Highlights: • DHA rescues FXR expression in alcoholic livers. • DHA improves alcoholic liver inflammation and steatosis in a FXR-dependent way. • DHA alleviates ethanol-induced hepatocyte steatosis by activation of FXR.

Dihydroartemisinin protects against alcoholic liver injury through alleviating hepatocyte steatosis in a farnesoid X receptor-dependent manner

International Nuclear Information System (INIS)

Xu, Wenxuan; Lu, Chunfeng; Yao, Lu; Zhang, Feng; Shao, Jiangjuan; Zheng, Shizhong

2017-01-01

Alcoholic liver disease (ALD) is a common etiology of liver diseases, characterized by hepatic steatosis. We previously identified farnesoid X receptor (FXR) as a potential therapeutic target for ALD. Dihydroartemisinin (DHA) has been recently identified to possess potent pharmacological activities on liver diseases. This study was aimed to explore the impact of DHA on ALD and further elaborate the underlying mechanisms. Gain- or loss-of-function analyses of FXR were applied in both in vivo and in vitro studies. Results demonstrated that DHA rescued FXR expression and activity in alcoholic rat livers. DHA also reduced serodiagnostic markers of liver injury, including aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase, and lactate dehydrogenase. DHA improved alcohol-induced liver histological lesions, expression of inflammation genes, and inflammatory cell infiltration. In addition, DHA not only attenuated hyperlipidemia but also reduced hepatic steatosis through regulating lipogenesis and lipolysis genes. In vitro experiments further consolidated the concept that DHA ameliorated ethanol-caused hepatocyte injury and steatosis. Noteworthily, DHA effects were reinforced by FXR agonist obeticholic acid or FXR expression plasmids but abrogated by FXR antagonist Z-guggulsterone or FXR siRNA. In summary, DHA significantly improved alcoholic liver injury by inhibiting hepatic steatosis, which was dependent on its activation of FXR in hepatocytes. - Highlights: • DHA rescues FXR expression in alcoholic livers. • DHA improves alcoholic liver inflammation and steatosis in a FXR-dependent way. • DHA alleviates ethanol-induced hepatocyte steatosis by activation of FXR.

Evidence of a DHA Signature in the Lipidome and Metabolome of Human Hepatocytes

Directory of Open Access Journals (Sweden)

Veronica Ghini

2017-02-01

Full Text Available Cell supplementation with bioactive molecules often causes a perturbation in the whole intracellular environment. Omics techniques can be applied for the assessment of this perturbation. In this study, the overall effect of docosahexaenoic acid (DHA supplementation on cultured human hepatocyte lipidome and metabolome has been investigated using nuclear magnetic resonance (NMR in combination with traditional techniques. The effect of two additional bioactives sharing with DHA the lipid-lowering effect—propionic acid (PRO and protocatechuic acid (PCA—has also been evaluated in the context of possible synergism. NMR analysis of the cell lipid extracts showed that DHA supplementation, alone or in combination with PCA or PRO, strongly altered the cell lipid profile. The perfect discrimination between cells receiving DHA (alone or in combination and the other cells reinforced the idea of a global rearrangement of the lipid environment induced by DHA. Notably, gas chromatography and fluorimetric analyses confirmed the strong discrimination obtained by NMR. The DHA signature was evidenced not only in the cell lipidome, but also in the metabolome. Results reported herein indicate that NMR, combined with other techniques, represents a fundamental approach to studying the effect of bioactive supplementation, particularly in the case of molecules with a broad spectrum of mechanisms of action.

Role of DHA in aging-related changes in mouse brain synaptic plasma membrane proteome.

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Sidhu, Vishaldeep K; Huang, Bill X; Desai, Abhishek; Kevala, Karl; Kim, Hee-Yong

2016-05-01

Aging has been related to diminished cognitive function, which could be a result of ineffective synaptic function. We have previously shown that synaptic plasma membrane proteins supporting synaptic integrity and neurotransmission were downregulated in docosahexaenoic acid (DHA)-deprived brains, suggesting an important role of DHA in synaptic function. In this study, we demonstrate aging-induced synaptic proteome changes and DHA-dependent mitigation of such changes using mass spectrometry-based protein quantitation combined with western blot or messenger RNA analysis. We found significant reduction of 15 synaptic plasma membrane proteins in aging brains including fodrin-α, synaptopodin, postsynaptic density protein 95, synaptic vesicle glycoprotein 2B, synaptosomal-associated protein 25, synaptosomal-associated protein-α, N-methyl-D-aspartate receptor subunit epsilon-2 precursor, AMPA2, AP2, VGluT1, munc18-1, dynamin-1, vesicle-associated membrane protein 2, rab3A, and EAAT1, most of which are involved in synaptic transmission. Notably, the first 9 proteins were further reduced when brain DHA was depleted by diet, indicating that DHA plays an important role in sustaining these synaptic proteins downregulated during aging. Reduction of 2 of these proteins was reversed by raising the brain DHA level by supplementing aged animals with an omega-3 fatty acid sufficient diet for 2 months. The recognition memory compromised in DHA-depleted animals was also improved. Our results suggest a potential role of DHA in alleviating aging-associated cognitive decline by offsetting the loss of neurotransmission-regulating synaptic proteins involved in synaptic function. Published by Elsevier Inc.

Thraustochytrids as production organisms for docosahexaenoic acid (DHA), squalene, and carotenoids.

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Aasen, Inga Marie; Ertesvåg, Helga; Heggeset, Tonje Marita Bjerkan; Liu, Bin; Brautaset, Trygve; Vadstein, Olav; Ellingsen, Trond E

2016-05-01

Thraustochytrids have been applied for industrial production of the omega-3 fatty acid docosahexaenoic (DHA) since the 1990s. During more than 20 years of research on this group of marine, heterotrophic microorganisms, considerable increases in DHA productivities have been obtained by process and medium optimization. Strains of thraustochytrids also produce high levels of squalene and carotenoids, two other commercially interesting compounds with a rapidly growing market potential, but where yet few studies on process optimization have been reported. Thraustochytrids use two pathways for fatty acid synthesis. The saturated fatty acids are produced by the standard fatty acid synthesis, while DHA is synthesized by a polyketide synthase. However, fundamental knowledge about the relationship between the two pathways is still lacking. In the present review, we extract main findings from the high number of reports on process optimization for DHA production and interpret these in the light of the current knowledge of DHA synthesis in thraustochytrids and lipid accumulation in oleaginous microorganisms in general. We also summarize published reports on squalene and carotenoid production and review the current status on strain improvement, which has been hampered by the yet very few published genome sequences and the lack of tools for gene transfer to the organisms. As more sequences now are becoming available, targets for strain improvement can be identified and open for a system-level metabolic engineering for improved productivities.

Engineering of EPA/DHA omega-3 fatty acid production by Lactococcus lactis subsp. cremoris MG1363.

Science.gov (United States)

Amiri-Jami, Mitra; Lapointe, Gisele; Griffiths, Mansel W

2014-04-01

Eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) have been shown to be of major importance in human health. Therefore, these essential polyunsaturated fatty acids have received considerable attention in both human and farm animal nutrition. Currently, fish and fish oils are the main dietary sources of EPA/DHA. To generate sustainable novel sources for EPA and DHA, the 35-kb EPA/DHA synthesis gene cluster was isolated from a marine bacterium, Shewanella baltica MAC1. To streamline the introduction of the genes into food-grade microorganisms such as lactic acid bacteria, unnecessary genes located upstream and downstream of the EPA/DHA gene cluster were deleted. Recombinant Escherichia coli harboring the 20-kb gene cluster produced 3.5- to 6.1-fold more EPA than those carrying the 35-kb DNA fragment coding for EPA/DHA synthesis. The 20-kb EPA/DHA gene cluster was cloned into a modified broad-host-range low copy number vector, pIL252m (4.7 kb, Ery) and expressed in Lactococcus lactis subsp. cremoris MG1363. Recombinant L. lactis produced DHA (1.35 ± 0.5 mg g(-1) cell dry weight) and EPA (0.12 ± 0.04 mg g(-1) cell dry weight). This is believed to be the first successful cloning and expression of EPA/DHA synthesis gene cluster in lactic acid bacteria. Our findings advance the future use of EPA/DHA-producing lactic acid bacteria in such applications as dairy starters, silage adjuncts, and animal feed supplements.

Mechanism by which DHA inhibits the aggregation of KLVFFA peptides: A molecular dynamics study

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Zhou, Hong; Liu, Shengtang; Shao, Qiwen; Ma, Dongfang; Yang, Zaixing; Zhou, Ruhong

2018-03-01

Docosahexaenoic acid (DHA) is one of the omega-3 polyunsaturated fatty acids, which has shown promising applications in lowering Aβ peptide neurotoxicity in vitro by preventing aggregation of Aβ peptides and relieving accumulation of Aβ fibrils. Unfortunately, the underlying molecular mechanisms of how DHA interferes with the aggregation of Aβ peptides remain largely enigmatic. Herein, aggregation behaviors of amyloid-β(Aβ)16-21 peptides (KLVFFA) with or without the presence of a DHA molecule were comparatively studied using extensive all-atom molecular dynamics simulations. We found that DHA could effectively suppress the aggregation of KLVFFA peptides by redirecting peptides to unstructured oligomers. The highly hydrophobic and flexible nature of DHA made it randomly but tightly entangled with Leu-17, Phe-19, and Phe-20 residues to form unstructured but stable complexes. These lower-ordered unstructured oligomers could eventually pass through energy barriers to form ordered β-sheet structures through large conformational fluctuations. This study depicts a microscopic picture for understanding the role and mechanism of DHA in inhibition of aggregation of Aβ peptides, which is generally believed as one of the important pathogenic mechanisms of Alzheimer's disease.

Regulation of the Docosapentaenoic Acid/Docosahexaenoic Acid Ratio (DPA/DHA Ratio) in Schizochytrium limacinum B4D1.

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Zhang, Ke; Li, Huidong; Chen, Wuxi; Zhao, Minli; Cui, Haiyang; Min, Qingsong; Wang, Haijun; Chen, Shulin; Li, Demao

2017-05-01

Docosapentaenoic acid/docosahexaenoic acid ratio (DPA/DHA ratio) in Schizochytrium was relatively stable. But ideally the ratio of DPA/DHA will vary according to the desired end use. This study reports several ways of modulating the DPA/DHA ratio. Incubation times changed the DPA/DHA ratio, and changes in this ratio were associated with the variations in the saturated fatty acid (SFAs) content. Propionic acid sharply increased the SFAs content in lipids, dramatically decreased the even-chain SFAs content, and reduced the DPA/DHA ratio. Pentanoic acid (C5:0) and heptanoic acid (C7:0) had similar effects as propionic acid, whereas butyric acid (C4:0), hexanoic acid (C6:0), and octanoic acid (C8:0) did not change the fatty acid profile and the DPA/DHA ratio. Transcription analyses show that β-oxidation might be responsible for this phenomenon. Iodoacetamide upregulated polyunsaturated fatty acid (PUFA) synthase genes, reduced the DHA content, and improved the DPA content, causing the DPA/DHA ratio to increase. These results present new insights into the regulation of the DPA/DHA ratio.

Shikimate dehydrogenase from Pinu sylvestris L. needles

International Nuclear Information System (INIS)

Osipov, V.I.; Shein, I.V.

1986-01-01

Shikimate dehydrogenase was isolated by extraction from pine needles and partially purified by fractionation with ammonium sulfate. In conifers, in contrast to other plants, all three isoenzymes of shikimate dehydrogenase exhibit activity not only with NADP + , but also with NAD + . The values of K/sub m/ for shikimate, when NADP + and NAD + are used as cofactors, are 0.22 and 1.13 mM, respectively. The enzyme is maximally active at pH 10 with both cofactors. It is suggested that NAD-dependent shikimate dehydrogenase catalyzes the initial reaction of the alternative pathway of the conversion of shikimic acid to hydroxybenzoic acid. The peculiarities of the organization and regulation of the initial reactions of the shikimate pathway in conifers and in plants with shikimate dehydrogenase absolutely specific for NADP are discussed

Dietary supplementation with docosahexaenoic acid (DHA) improves seminal antioxidant status and decreases sperm DNA fragmentation.

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Martínez-Soto, Juan Carlos; Domingo, Joan Carles; Cordobilla, Begoña; Nicolás, María; Fernández, Laura; Albero, Pilar; Gadea, Joaquín; Landeras, José

2016-12-01

The purpose of this study was to evaluate the effect of docosahexaenoic acid (DHA) dietary supplementation on semen quality, fatty acid composition, antioxidant capacity, and DNA fragmentation. In this randomized, double blind, placebo-controlled, parallel-group study, 74 subjects were recruited and randomly assigned to either the placebo group (n=32) or to the DHA group (n=42) to consume three 500-mg capsules of oil per day over 10 weeks. The placebo group received 1,500 mg/day of sunflower oil and the DHA group 1,500 mg/day of DHA-enriched oil. Seminal parameters (semen volume, sperm concentration, motility, morphology, and vitality), total antioxidant capacity, deoxyribonucleic acid fragmentation, and lipid composition were evaluated prior to the treatment and after 10 weeks. Finally, 57 subjects were included in the study with 25 in the placebo group and 32 in the DHA group. No differences were found in traditional sperm parameters or lipid composition of the sperm membrane after treatment. However, an increase in DHA and Omega-3 fatty acid content in seminal plasma, an improvement in antioxidant status, and a reduction in the percentage of spermatozoa with deoxyribonucleic acid damage were observed in the DHA group after 10 weeks of treatment.

Inosine monophosphate dehydrogenase messenger RNA expression is correlated to clinical outcomes in mycophenolate mofetil-treated kidney transplant patients, whereas inosine monophosphate dehydrogenase activity is not

NARCIS (Netherlands)

Sombogaard, Ferdi; Peeters, Annemiek M. A.; Baan, Carla C.; Mathot, Ron A. A.; Quaedackers, Monique E.; Vulto, Arnold G.; Weimar, Willem; van Gelder, Teun

2009-01-01

Measurement of the pharmacodynamic biomarker inosine monophosphate dehydrogenase (IMPDH) activity in renal transplant recipients has been proposed to reflect the biological effect better than using pharmacokinetic parameters to monitor mycophenolate mofetil therapy. The IMPDH assays are however

DHA Mitigates Autistic Behaviors Accompanied by Dopaminergic Change in a Gene/Prenatal Stress Mouse Model.

Science.gov (United States)

Matsui, Fumihiro; Hecht, Patrick; Yoshimoto, Kanji; Watanabe, Yoshihisa; Morimoto, Masafumi; Fritsche, Kevin; Will, Matthew; Beversdorf, David

2018-02-10

Autism Spectrum Disorder (ASD) is characterized by impairments in social interaction, social communication, and repetitive and stereotyped behaviors. Recent work has begun to explore gene × environmental interactions in the etiology of ASD. We previously reported that prenatal stress exposure in stress-susceptible heterozygous serotonin transporter (SERT) KO pregnant dams in a mouse model resulted in autism-like behavior in the offspring (SERT/S mice). The association between prenatal stress and ASD appears to be affected by maternal SERT genotype in clinical populations as well. Using the mouse model, we examined autistic-like behaviors in greater detail, and additionally explored whether diet supplementation with docosahexaenoic acid (DHA) may mitigate the behavioral changes. Only male SERT/S mice showed social impairment and stereotyped behavior, and DHA supplementation ameliorated some of these behaviors. We also measured monoamine levels in the SERT/S mice after three treatment paradigms: DHA-rich diet continuously from breeding (DHA diet), DHA-rich diet only after weaning (CTL/DHA diet) and control diet only (CTL diet). The dopamine (DA) content in the striatum was significantly increased in the SERT/S mice compared with wild-type (WT) mice, whereas no difference was observed with noradrenaline and serotonin content. Moreover, DA content in the striatum was significantly reduced in the SERT/S mice with the DHA-rich diet provided continuously from breeding. The results indicate that autism-associated behaviors and changes in the dopaminergic system in this setting can be mitigated with DHA supplementation. Copyright © 2017 IBRO. Published by Elsevier Ltd. All rights reserved.

Changes of α-glycerophosphate dehydrogenase activity in fatty liver of rats by amino acid imbalance

International Nuclear Information System (INIS)

Ogura, Masaji; Katsunuma, Eiichi; Akabane, Tomoko; Ogawa, Seiichi

1976-01-01

The previous study on the lipogenesis in the fatty livers of rats, which was induced by feeding the diet with imbalanced amino acid, revealed that the induction of this type of fatty livers was due mainly to the acceleration of triglyceride synthesis by the increase in both synthesis and esterification of fatty acid in the livers. Although many studies have been carried out on the dietary control of α-glycerophosphate dehydrogenase activity in rat livers, the enzyme change in amino acid imbalance has not been reported. In the present study, in order to elucidate the difference in the supply of glycerol moiety of triglyceride due to the imbalance, the change of the α-glycerophosphate dehydrogenase activity in livers was investigated. The experimental diets were 8% casein basal diet and basal + 0.3% DL-methionine imbalanced diet. 5 rats of each group were killed after 0.5 and 10 days on the diet, and the analysis of the lipid content in the livers and the determination of the α-glycerophosphate dehydrogenase activity were carried out. The linear response of the enzyme activity to time and protein concentration was obtained. The development of fatty livers was observed in the imbalanced diet group in the feeding period of 10 days. It was found that the specific activity of the imbalanced diet group increased significantly in 5 and 10 days as compared with that of the basal diet group. The elevation in the enzyme activity may suggest that the supply of α-glycerophosphate for triglyceride synthesis is also increased in this type of fatty livers. (Kako, I.)

Reversible inactivation of CO dehydrogenase with thiol compounds

Energy Technology Data Exchange (ETDEWEB)

Kreß, Oliver [Department of Microbiology, University of Bayreuth, 95440 Bayreuth (Germany); Gnida, Manuel [Department of Chemistry, University of Paderborn, 33098 Paderborn (Germany); Pelzmann, Astrid M. [Department of Microbiology, University of Bayreuth, 95440 Bayreuth (Germany); Marx, Christian [Institute of Biochemistry and Biophysics, Friedrich-Schiller-University of Jena, 07745 Jena (Germany); Meyer-Klaucke, Wolfram [Department of Chemistry, University of Paderborn, 33098 Paderborn (Germany); Meyer, Ortwin, E-mail: Ortwin.Meyer@uni-bayreuth.de [Department of Microbiology, University of Bayreuth, 95440 Bayreuth (Germany)

2014-05-09

Highlights: • Rather large thiols (e.g. coenzyme A) can reach the active site of CO dehydrogenase. • CO- and H{sub 2}-oxidizing activity of CO dehydrogenase is inhibited by thiols. • Inhibition by thiols was reversed by CO or upon lowering the thiol concentration. • Thiols coordinate the Cu ion in the [CuSMo(=O)OH] active site as a third ligand. - Abstract: Carbon monoxide dehydrogenase (CO dehydrogenase) from Oligotropha carboxidovorans is a structurally characterized member of the molybdenum hydroxylase enzyme family. It catalyzes the oxidation of CO (CO + H{sub 2}O → CO{sub 2} + 2e{sup −} + 2H{sup +}) which proceeds at a unique [CuSMo(=O)OH] metal cluster. Because of changing activities of CO dehydrogenase, particularly in subcellular fractions, we speculated whether the enzyme would be subject to regulation by thiols (RSH). Here we establish inhibition of CO dehydrogenase by thiols and report the corresponding K{sub i}-values (mM): L-cysteine (5.2), D-cysteine (9.7), N-acetyl-L-cysteine (8.2), D,L-homocysteine (25.8), L-cysteine–glycine (2.0), dithiothreitol (4.1), coenzyme A (8.3), and 2-mercaptoethanol (9.3). Inhibition of the enzyme was reversed by CO or upon lowering the thiol concentration. Electron paramagnetic resonance spectroscopy (EPR) and X-ray absorption spectroscopy (XAS) of thiol-inhibited CO dehydrogenase revealed a bimetallic site in which the RSH coordinates to the Cu-ion as a third ligand ([Mo{sup VI}(=O)OH{sub (2)}SCu{sup I}(SR)S-Cys]) leaving the redox state of the Cu(I) and the Mo(VI) unchanged. Collectively, our findings establish a regulation of CO dehydrogenase activity by thiols in vitro. They also corroborate the hypothesis that CO interacts with the Cu-ion first. The result that thiol compounds much larger than CO can freely travel through the substrate channel leading to the bimetallic cluster challenges previous concepts involving chaperone function and is of importance for an understanding how the sulfuration step in

Intraperitoneal administration of docosahexaenoic acid for 14days increases serum unesterified DHA and seizure latency in the maximal pentylenetetrazol model.

Science.gov (United States)

Trépanier, Marc-Olivier; Lim, Joonbum; Lai, Terence K Y; Cho, Hye Jin; Domenichiello, Anthony F; Chen, Chuck T; Taha, Ameer Y; Bazinet, Richard P; Burnham, W M

2014-04-01

Docosahexaenoic acid (DHA) is an omega-3 polyunsaturated fatty acid (n-3 PUFA) which has been shown to raise seizure thresholds following acute administration in rats. The aims of the present experiment were the following: 1) to test whether subchronic DHA administration raises seizure threshold in the maximal pentylenetetrazol (PTZ) model 24h following the last injection and 2) to determine whether the increase in seizure threshold is correlated with an increase in serum and/or brain DHA. Animals received daily intraperitoneal (i.p.) injections of 50mg/kg of DHA, DHA ethyl ester (DHA EE), or volume-matched vehicle (albumin/saline) for 14days. On day 15, one subset of animals was seizure tested in the maximal PTZ model (Experiment 1). In a separate (non-seizure tested) subset of animals, blood was collected, and brains were excised following high-energy, head-focused microwave fixation. Lipid analysis was performed on serum and brain (Experiment 2). For data analysis, the DHA and DHA EE groups were combined since they did not differ significantly from each other. In the maximal PTZ model, DHA significantly increased seizure latency by approximately 3-fold as compared to vehicle-injected animals. This increase in seizure latency was associated with an increase in serum unesterified DHA. Total brain DHA and brain unesterified DHA concentrations, however, did not differ significantly in the treatment and control groups. An increase in serum unesterified DHA concentration reflecting increased flux of DHA to the brain appears to explain changes in seizure threshold, independent of changes in brain DHA concentrations. Copyright © 2014 Elsevier Inc. All rights reserved.

Two-Stage Enzymatic Preparation of Eicosapentaenoic Acid (EPA) And Docosahexaenoic Acid (DHA) Enriched Fish Oil Triacylglycerols.

Science.gov (United States)

Zhang, Zhen; Liu, Fang; Ma, Xiang; Huang, Huihua; Wang, Yong

2018-01-10

Fish oil products in the form of triacylglycerols generally have relatively low contents of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) and so it is of potential research and industrial interest to enrich the related contents in commercial products. Thereby an economical and efficient two-stage preparation of EPA and DHA enriched fish oil triacylglycerols is proposed in this study. The first stage was the partial hydrolysis of fish oil by only 0.2 wt.‰ AY "Amano" 400SD which led to increases of EPA and DHA contents in acylglycerols from 19.30 and 13.09 wt % to 25.95 and 22.06 wt %, respectively. Subsequently, products of the first stage were subjected to transesterification with EPA and DHA enriched fatty acid ethyl esters (EDEE) as the second stage to afford EPA and DHA enriched fish oil triacylglycerols by using as low as 2 wt % Novozyme 435. EDEEs prepared from fish oil ethyl ester, and recycled DHA and EPA, respectively, were applied in this stage. Final products prepared with two different sources of EDEEs were composed of 97.62 and 95.92 wt % of triacylglycerols, respectively, with EPA and DHA contents of 28.20 and 21.41 wt % for the former and 25.61 and 17.40 wt % for the latter. Results not only demonstrate this two-stage process's capability and industrial value for enriching EPA and DHA in fish oil products, but also offer new opportunities for the development of fortified fish oil products.

Possible evidence that dehydroepiandrosterone sulfate (DHA-S) stimulates cervical ripening by a membrane-mediated process: Specific binding-sites in plasma membrane from human uterine cervix

International Nuclear Information System (INIS)

Ohno, T.; Imai, A.; Tamaya, T.

1991-01-01

Fetal adrenal steroid, dehydroepiandrosterone sulfate (DHA-S) is well known to promote cervical ripening in late pregnancy. The presence of sites specifically binding the DHA-S in plasma membrane was studied in human cervical fibroblasts prepared from pregnant uterus. The fibroblasts were incubated with 3 H DHA-S and then fractionated into plasma membranes, cytosol, nuclei, and other organella debris. The specific activity of 3H-count in the plasma membrane fraction was enriched ∼ 7-fold compared with the whole homogenate. When the isolated plasma membrane preparations from the fibroblasts were exposed to 3 H DHA-S, the binding showed saturation kinetics; an apparent equilibrium dissociation constant (Kd) of 12 nM, and the binding capacity (Bmax) of 1.25 pmol/mg protein. The present results suggest that DHA is bound to and recognized by components in plasma membrane, and may exert its action on cervical ripening through the membrane-mediated processes

Changes in Bioavailability of Omega-3 (DHA through Alpha-Tocopheryl Phosphate Mixture (TPM after Oral Administration in Rats

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Roksan Libinaki

2017-09-01

Full Text Available Benefits of Omega-3 Docosahexaenoic acid (DHA supplements are hindered by their poor solubility and bioavailability. This study investigated the bioavailability of various formulations of Omega-3 and tocopheryl phosphate mixture (TPM, following oral administration in rats, and assessed whether TPM could improve the oral absorption of DHA. The rats were administered with a high (265.7 mg/kg or low dose (88.6 mg/kg of DHA. TPM was examined at 1:0.1 w/w (low TPM dose and 1:0.5 w/w (high TPM dose. Over 24 h, the DHA plasma concentration followed a TPM dose-dependent relationship, reflected in the higher mean Cmax values (78.39 and 91.95 μg/mL and AUC values (1396.60 and 1560.60 for the low and high TPM, respectively. The biggest difference between the low dose DHA control (LDCont and TPM formulations was at 4 h after supplementation, where the low and high TPM showed a mean 20% (ns and 50% (p < 0.05 increase in DHA plasma concentrations versus the control formulation. After correcting for baseline endogenous DHA, the mean plasma DHA at 4 h produced by the LD-HTPM was nearly double (90% the LDC control (p = 0.057. This study demonstrated that co-administering omega-3 with TPM significantly increases the bioavailability of DHA in the plasma, suggesting potential use for commercially available TPM + DHA fortified products.

HUBUNGAN KECUKUPAN ASAM EIKOSAPENTANOAT (EPA, ASAM DOKOSAHEKSANOAT (DHA IKAN DAN STATUS GIZI DENGAN PRESTASI BELAJAR SISWA

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Siti Zulaihah

2012-04-01

Full Text Available ABSTRACT   Background: Fish contain of high protein, EPA, DHA needed for the formation of brain cell and improving intelligence. Consuming fish and other sea food make healthy and improve the brain ability to reach optimum study achievement. In 2003, fish consumption in Indonesia is still low 24,67kg/capita/year. Based on BPS 2002, fish consumption in Semarang is 5,38%. The fish consumption has a big influence on nutrition sufficiency especially EPA and DHA, nutrition status and attaining healthy and smart Indonesian human resources. Goal: To analyze the relationship between fish meal frequency, fish EPA and DHA recommended and nutrition status with student's study achievement. Method: The research used survey method, analytical research, and cross -sectional time approach. This research was conducted on September-October 2004. Sample was 100 subject of SD Taqwiyatui Wathon (grade IV are 54 person, grade V are 46 person by using Stratified Random Sampling method. The data preparation used NUTRISOFT. Result: Fish frequently consumed by responden was bandeng (Chanos chanos 5%, tongkol (Euthynnus allitteratus rafmescue 4%, kembung (Scomber kanoguria russei 1% and mujair (Tilapia mossambica 1 %. EPA, DHA % RDA defisit 62%, normal nutritional status 93% and average category of study achievement 55%. There was relation between fish meal frequency and fish EPA, DHA % RDA (ρ=0,000, there was no relation between fish meal frequency and nutritional status (ρ=0,213, there was relation between fish meal frequency and study achievement (ρ=0,000, there was relation between fish EPA, DHA recommendation and study achievement (ρ=0,000, and there was no relation between nutrition status and study achievement (ρ=0.378. Based on Pearson correlation test, there was no relation between fish EPA, DHA recommendation and nutritional status (ρ=0,000. Conclution: Students with frequent fish consumption and high RDA of EPA, DHA % RDA showed better study achievement

Effects of a 12-week high-α-linolenic acid intervention on EPA and DHA concentrations in red blood cells and plasma oxylipin pattern in subjects with a low EPA and DHA status.

Science.gov (United States)

Greupner, Theresa; Kutzner, Laura; Nolte, Fabian; Strangmann, Alena; Kohrs, Heike; Hahn, Andreas; Schebb, Nils Helge; Schuchardt, Jan Philipp

2018-03-01

The essential omega-3 fatty acid alpha-linolenic acid (ALA, 18:3n3) can be converted into EPA and DHA. The aim of the present study was to determine the effect of a high-ALA diet on EPA and DHA levels in red blood cells (RBCs) and their oxylipins in the plasma of subjects with a low EPA and DHA status. Fatty acid concentrations [μg mL -1 ] and relative amounts [% of total fatty acids] in the RBCs of 19 healthy men (mean age 26.4 ± 4.6 years) were analyzed by means of GC-FID. Free plasma oxylipin concentrations were determined by LC-MS based targeted metabolomics. Samples were collected and analyzed at baseline (week 0) and after 1 (week 1), 3 (week 3), 6 (week 6), and 12 (week 12) weeks of high dietary ALA intake (14.0 ± 0.45 g day -1 ). ALA concentrations significantly (p DHA concentrations unexpectedly decreased from 41.0 ± 1.93 (week 0) to 37.0 ± 1.32 (week 1), 36.1 ± 1.37 (week 3), 35.1 ± 1.06 (p = 0.010, week 6), and 30.4 ± 1.09 (p DHA amounts were unchanged during the intervention (week 0: 4.63 ± 0.19, week 1: 4.67 ± 0.16, week 3: 4.61 ± 0.13, week 6: 4.73 ± 0.15, week 12: 4.52 ± 0.11). ALA- and EPA-derived hydroxy- and dihydroxy-PUFA increased similarly to their PUFA precursors, although in the case of ALA-derived oxylipins, the concentrations increased less rapidly and to a lesser extent compared to the concentrations of their precursor FA. LA-derived oxylipins remained unchanged and arachidonic acid and DHA oxylipin concentrations were not significantly changed. Our results confirm that the intake of ALA is not a sufficient source for the increase of EPA + DHA in subjects on a Western diet. Specifically, a high-ALA diet results in increased EPA and declined DHA concentrations. However, the changes effectively balance each other out so that ΣEPA + DHA in RBCs - which is an established marker for health protective effects of omega-3-PUFA - remains constant. The PUFA levels in RBCs reflect the concentration and its changes in plasma hydroxy- and

DHA Concentration and Purification from the Marine Heterotrophic Microalga Crypthecodinium cohnii CCMP 316 by Winterization and Urea Complexation

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Ana Mendes

2007-01-01

Full Text Available A simple and inexpensive procedure involving saponification and methylation in wet biomass, winterization and urea complexation in a sequential way has been developed in order to concentrate docosahexaenoic acid (DHA from Crypthecodinium cohnii CCMP 316 biomass. Different urea/fatty acid ratios and crystallization temperatures were tested in the urea complexation method. ANOVA test revealed that, in the studied range, the temperature had the most significant effect on the DHA concentration. The highest DHA fraction (99.2 % of total fatty acids was found at the urea/fatty acid ratio of 3.5 at the crystallization temperatures of 4 and 8 °C. The highest DHA recovery (49.9 % was observed at 24 °C at the urea/fatty acid ratio of 4.0, corresponding to 89.4 % DHA of total fatty acids. Considering the high proportions of DHA obtained in the non-urea complexing fractions, the current procedure was an appropriate way to concentrate and purify DHA from C. cohnii.

Relative levels of dietary EPA and DHA impact gastric oxidation and essential fatty acid uptake.

Science.gov (United States)

Dasilva, Gabriel; Boller, Matthew; Medina, Isabel; Storch, Judith

2018-05-01

Previous research showed that increasing the proportion of docosahexaenoic acid (DHA) in marine lipid supplements significantly reduces associated health benefits compared with balanced eicosapentaenoic acid (EPA):DHA supplementation Dasilva et al., 2015 [1]. It was therefore hypothesized that the EPA and DHA molecules might have differential resistance to oxidation during gastric digestion and that the oxidation level achieved could be inversely correlated with intestinal absorption and, hence, with the resultant health benefits. Accordingly, we tested this proposed mechanism of action by investigating the degree of oxidation in the stomach, and the levels of bioaccessible lipids, of varying molar proportions of DHA and EPA (2:1, 1:1 and 1:2) using the dynamic gastrointestinal tract model TIM-1. In addition, small intestine enterocyte absorption and metabolism were simulated by Caco-2 cell monolayers that were incubated with these same varying proportions of DHA and EPA, and comparing oxidized and nonoxidized polyunsaturated fatty acids (PUFAs). The results show an inverse correlation between lipid oxidation products in the stomach and the levels of bioaccessible lipids. The balanced 1:1 EPA:DHA diet resulted in lower oxidation of PUFAs during stomach digestion relative to the other ratios tested. Finally, cell-based studies showed significantly lower assimilation of oxidized EPA and DHA substrates compared to nonoxidized PUFAs, as well as significant differences between the net uptake of EPA and DHA. Overall, the present work suggests that the correct design of diets and/or supplements containing marine lipids can strongly influence the stability and bioaccessibility of PUFAs during gastrointestinal digestion and subsequent absorption. This could modulate their health benefits related with inflammation, oxidative stress and metabolic disorders. Copyright © 2017 Elsevier Inc. All rights reserved.

A Critical Review on the Effect of Docosahexaenoic Acid (DHA) on Cancer Cell Cycle Progression.

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Newell, Marnie; Baker, Kristi; Postovit, Lynne M; Field, Catherine J

2017-08-17

Globally, there were 14.1 million new cancer diagnoses and 8.2 million cancer deaths in 2012. For many cancers, conventional therapies are limited in their successes and an improved understanding of disease progression is needed in conjunction with exploration of alternative therapies. The long chain polyunsaturated fatty acid, docosahexaenoic acid (DHA), has been shown to enhance many cellular responses that reduce cancer cell viability and decrease proliferation both in vitro and in vivo. A small number of studies suggest that DHA improves chemotherapy outcomes in cancer patients. It is readily incorporated into cancer cell membranes and, as a result there has been considerable research regarding cell membrane initiated events. For example, DHA has been shown to mediate the induction of apoptosis/reduction of proliferation in vitro and in vivo. However, there is limited research into the effect of DHA on cell cycle regulation in cancer cells and the mechanism(s) by which DHA acts are not fully understood. The purpose of the current review is to provide a critical examination of the literature investigating the ability of DHA to stall progression during different cell cycle phases in cancer cells, as well as the consequences that these changes may have on tumour growth, independently and in conjunction with chemotherapy.

High-fat meals rich in EPA plus DHA compared with DHA only have differential effects on postprandial lipemia and plasma 8-isoprostane F2α concentrations relative to a control high-oleic acid meal: a randomized controlled trial.

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Purcell, Robert; Latham, Sally H; Botham, Kathleen M; Hall, Wendy L; Wheeler-Jones, Caroline P D

2014-10-01

Eicosapentaenoic acid (EPA) plus docosahexaenoic acid (DHA) supplementation has beneficial cardiovascular effects, but postprandial influences of these individual fatty acids are unclear. The primary objective was to determine the vascular effects of EPA + DHA compared with DHA only during postprandial lipemia relative to control high-oleic acid meals; the secondary objective was to characterize the effects of linoleic acid-enriched high-fat meals relative to the control meal. We conducted a randomized, controlled, double-blind crossover trial of 4 high-fat (75-g) meals containing 1) high-oleic acid sunflower oil (HOS; control), 2) HOS + fish oil (FO; 5 g EPA and DHA), 3) HOS + algal oil (AO; 5 g DHA), and 4) high-linoleic acid sunflower oil (HLS) in 16 healthy men (aged 35-70 y) with higher than optimal fasting triacylglycerol concentrations (mean ± SD triacylglycerol, 1.9 ± 0.5 mmol/L). Elevations in triacylglycerol concentration relative to baseline were slightly reduced after FO and HLS compared with the HOS control (P acids after a mixed meal was inhibited after AO (Δ 0-3 h, P DHA-rich fish oil compared with DHA-rich AO, but these differences were not associated with consistent effects on postprandial vascular function or lipemia. More detailed analyses of polyunsaturated fatty acid-derived lipid mediators are required to determine possible divergent functional effects of single meals rich in either DHA or EPA. This trial was registered at clinicaltrials.gov as NCT01618071.

Glutathionylation regulates cytosolic NADP+-dependent isocitrate dehydrogenase activity.

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Shin, Seoung Woo; Oh, Chang Joo; Kil, In Sup; Park, Jeen-Woo

2009-04-01

Cytosolic NADP+-dependent isocitrate dehydrogenase (IDPc) is susceptible to inactivation by numerous thiol-modifying reagents. This study now reports that Cys269 of IDPc is a target for S-glutathionylation and that this modification is reversed by dithiothreitol as well as enzymatically by cytosolic glutaredoxin in the presence of GSH. Glutathionylated IDPc was significantly less susceptible than native protein to peptide fragmentation by reactive oxygen species and proteolytic digestion. Glutathionylation may play a protective role in the degradation of protein through the structural alterations of IDPc. HEK293 cells treated with diamide displayed decreased IDPc activity and accumulated glutathionylated enzyme. Using immunoprecipitation with an anti-IDPc IgG and immunoblotting with an anti-GSH IgG, we purified and positively identified glutathionylated IDPc from the kidneys of mice subjected to ischemia/reperfusion injury and from the livers of ethanol-administered rats. These results suggest that IDPc activity is modulated through enzymatic glutathionylation and deglutathionylation during oxidative stress.

Determinants of DHA levels in early infancy: differential effects of breast milk and direct fish oil supplementation.

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Meldrum, S J; D'Vaz, N; Casadio, Y; Dunstan, J A; Niels Krogsgaard-Larsen, N; Simmer, K; Prescott, S L

2012-06-01

Although omega (n)-3 long-chain polyunsaturated fatty acids (LCPUFA), particularly docosahexaenoic acid (DHA), intakes are important during infancy, the optimal method of increasing infant status remains unclear. We hypothesized that high-dose infant fish oil supplementation would have greater relative effects upon n-3 LCPUFA status at six months of age than breast milk fatty acids. Infants (n=420) were supplemented daily from birth to six months with fish oil or placebo. In a subset of infants, LCPUFA levels were measured in cord blood, breast milk and in infant blood at 6 months. DHA levels increased in the fish oil group relative to placebo (p<05). Breast milk DHA was the strongest predictor of infant erythrocyte DHA levels (p=<001). This remained significant after adjustment for cord blood DHA, supplementation group and adherence. In this cohort, breast milk DHA was a greater determinant of infant erythrocyte n-3 LCPUFA status, than direct supplementation with fish oil. Copyright © 2012 Elsevier Ltd. All rights reserved.

Identification of DHA-23, a Novel Plasmid-mediated and Inducible AmpC beta-Lactamase from Enterobacteriaceae in Northern Taiwan

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Wen-Shyang eHsieh

2015-05-01

Full Text Available Objectives: AmpC β-lactamases are classified as Amber Class C and Bush Group 1. AmpC β-lactamases can hydrolyze broad and extended-spectrum cephalosporins, and are not inhibited by β-lactamase inhibitors such as clavulanic acid. This study was conducted to identify DHA-23, a novel plasmid-mediated and inducible AmpC β-lactamase obtained from Enterobacteriaceae. Methods: A total of 210 carbapenem-resistant Enterobacteriaceae isolates were collected from a medical center (comprising 2 branches in Northern Taiwan during 2009–2012. AmpC β-lactamase genes were analyzed through a polymerase chain reaction using plasmid DNA templates and gene sequencing. The genetic relationships of the isolates were typed using pulsed-field gel electrophoresis following the digestion of intact genomic DNA by using XbaI. Results: Three enterobacterial isolates (one Escherichia coli and 2 Klebsiella pneumoniae were obtained from 3 hospitalized patients. All 3 isolates were resistant or intermediately susceptible to all β-lactams, and exhibited reduced susceptibility to carbapenems. These 3 isolates expressed a novel AmpC β-lactamase, designated DHA-23, approved by the curators of the Lahey website. DHA-23 differs from DHA-1 and DHA-6 by one amino acid substitution (Ser245Ala, exhibiting 2 amino acid changes compared with DHA-7 and DHA-Morganella morganii; 3 amino acid changes compared with DHA-3; 4 amino acid changes compared with DHA-5; and 8 amino acid changes compared with DHA-2 (> 97% identity. This AmpC β-lactamase is inducible using a system involving ampR. Conclusion: This is the first report to address DHA-23, a novel AmpC β-lactamase. DHA-type β-lactamases are continuous threat in Taiwan.

Evidence for the Initial Steps of DHA Biohydrogenation by Mixed Ruminal Microorganisms from Sheep Involves Formation of Conjugated Fatty Acids.

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Aldai, Noelia; Delmonte, Pierluigi; Alves, Susana P; Bessa, Rui J B; Kramer, John K G

2018-01-31

Incubation of DHA with sheep rumen fluid resulted in 80% disappearance in 6 h. The products were analyzed as their fatty acid (FA) methyl esters by GC-FID on SP-2560 and SLB-IL111 columns. The GC-online reduction × GC and GC-MS techniques demonstrated that all DHA metabolites retained the C22 structure (no evidence of chain-shortening). Two new transient DHA products were identified: mono-trans methylene interrupted-DHA and monoconjugated DHA (MC-DHA) isomers. Identification of MC-DHA was confirmed by their predicted elution using equivalent chain length differences from C18 FA, their molecular ions, and the 22:5 products formed which were the most abundant at 6 h. The 22:5 structures were established by fragmentation of their 4,4-dimethyloxazoline derivatives, and all 22:5 products contained an isolated double bond, suggesting formation via MC-DHA. The most abundant c4,c7,c10,t14,c19-22:5 appeared to be formed by unknown isomerases. Results suggest that the initial biohydrogenation of DHA was analogous to that of C18 FA.

Docosahexaenoic acid (DHA): An essential nutrient and a nutraceutical for brain health and diseases.

Science.gov (United States)

Sun, Grace Y; Simonyi, Agnes; Fritsche, Kevin L; Chuang, Dennis Y; Hannink, Mark; Gu, Zezong; Greenlief, C Michael; Yao, Jeffrey K; Lee, James C; Beversdorf, David Q

2017-03-10

Docosahexaenoic acid (DHA), a polyunsaturated fatty acid (PUFA) enriched in phospholipids in the brain and retina, is known to play multi-functional roles in brain health and diseases. While arachidonic acid (AA) is released from membrane phospholipids by cytosolic phospholipase A 2 (cPLA 2 ), DHA is linked to action of the Ca 2+ -independent iPLA2. DHA undergoes enzymatic conversion by 15-lipoxygenase (Alox 15) to form oxylipins including resolvins and neuroprotectins, which are powerful lipid mediators. DHA can also undergo non-enzymatic conversion by reacting with oxygen free radicals (ROS), which cause the production of 4-hydoxyhexenal (4-HHE), an aldehyde derivative which can form adducts with DNA, proteins and lipids. In studies with both animal models and humans, there is evidence that inadequate intake of maternal n-3 PUFA may lead to aberrant development and function of the central nervous system (CNS). What is less certain is whether consumption of n-3 PUFA is important in maintaining brain health throughout one's life span. Evidence mostly from non-human studies suggests that DHA intake above normal nutritional requirements might modify the risk/course of a number of diseases of the brain. This concept has fueled much of the present interest in DHA research, in particular, in attempts to delineate mechanisms whereby DHA may serve as a nutraceutical and confer neuroprotective effects. Current studies have revealed ability for the oxylipins to regulation of cell redox homeostasis through the Nuclear factor (erythroid-derived 2)-like 2/Antioxidant response element (Nrf2/ARE) anti-oxidant pathway, and impact signaling pathways associated with neurotransmitters, and modulation of neuronal functions involving brain-derived neurotropic factor (BDNF). This review is aimed at describing recent studies elaborating these mechanisms with special regard to aging and Alzheimer's disease, autism spectrum disorder, schizophrenia, traumatic brain injury, and stroke

Clinical effects of diet supplementation with DHA in pediatric patients suffering from cystic fibrosis.

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Leggieri, E; De Biase, R V; Savi, D; Zullo, S; Halili, I; Quattrucci, S

2013-08-01

Cystic fibrosis (CF) patients present an altered fatty acid (FA) metabolism characterized by imbalance in the arachidonic/docosohexasenoic acid (AA/DHA) ratio in favour of the former which can contribute to the increase in pulmonary inflammation. The present study aims to assess respiratory, nutritional, clinical and laboratory parameters, and inflammatory markers after six months of DHA supplementation in paediatric patients suffering from CF. A dose of 1 g/10 kg/die was administered to ten CF patients of paediatric age for the first month and 250 mg/10 kg/die for the remaining 5 months. We carried out follow-ups at T0 (baseline), T6 (after six months of the diet) and T12 (six months after supplementation was interrupted) during which respiratory, nutritional, clinical and laboratory parameters were assessed. After six months of DHA supplementation inflammatory marker levels had diminished: interleukin 8 (IL-8) and Tumour Necrosis Factor Alfa (TNF-α) in serum, and calprotectin in stools. In addition, auxometric parameters were improved as was the clinical condition of patients, who tolerated DHA well. Dietetic integration with DHA seems to improve clinical condition and the inflammatory pulmonary and intestinal state of pediatric patients suffering from CF.

Physicochemical Properties and Storage Stability of Microencapsulated DHA-Rich Oil with Different Wall Materials.

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Chen, Wuxi; Wang, Haijun; Zhang, Ke; Gao, Feng; Chen, Shulin; Li, Demao

2016-08-01

This study aimed to evaluate the physicochemical properties and storage stability of microencapsulated DHA-rich oil spray dried with different wall materials: model 1 (modified starch, gum arabic, and maltodextrin), model 2 (soy protein isolate, gum arabic, and maltodextrin), and model 3 (casein, glucose, and lactose). The results indicated that model 3 exhibited the highest microencapsulation efficiency (98.66 %) and emulsion stability (>99 %), with a moisture content and mean particle size of 1.663 % and 14.173 μm, respectively. Differential scanning calorimetry analysis indicated that the Tm of DHA-rich oil microcapsules was high, suggesting that the entire structure of the microcapsules remained stable during thermal processing. A thermogravimetric analysis curve showed that the product lost 5 % of its weight at 172 °C and the wall material started to degrade at 236 °C. The peroxide value of microencapsulated DHA-rich oil remained at one ninth after accelerated oxidation at 45 °C for 8 weeks to that of the unencapsulated DHA-rich oil, thus revealing the promising oxidation stability of DHA-rich oil in microcapsules.

Glycerol and environmental factors: effects on 1,3-propanediol production and NAD(+) regeneration in Lactobacillus panis PM1.

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Kang, T S; Korber, D R; Tanaka, T

2013-10-01

This study was conducted to understand the influences of fermentation factors in NADH recycling and mechanisms of 1,3-propanediol (1,3-PDO) production in Lactobacillus panis PM1. We conducted metabolite analyses, qRT-PCR of the glycerol reductive pathway [glycerol dehydratase (DhaB) and 1,3-PDO dehydrogenase (DhaT)] and DhaT activity assays at different pH, temperature and initial glycerol concentrations. The supplementation of 150 mmol l(-1) glycerol caused a shift in NADH flux from ethanol to 1,3-PDO production, whereas 300 mol l(-1) glycerol negatively affected the regeneration of NAD(+) via 1,3-PDO production. This retardation decreased transcription levels and specific activities of DhaT. The decreased DhaT activity eventually caused the shutdown of 1,3-PDO production. Temperature and pH did not significantly affect the specific activity of DhaT, whereas expression of genes for DhaB and DhaT was activated under acidic conditions. Moreover, fresh glucose addition after its depletion could not restart the glycerol reduction, but increased ethanol production. Those environmental factors affect 1,3-PDO production in different ways through changing the expression level of enzymes and shifting the NAD(+) regeneration pathways. Our findings elucidated a key element to optimize 1,3-PDO production by Lact. panis PM1, which potentially improves 1,3-PDO manufacturing efficiencies. © 2013 The Society for Applied Microbiology.

Vitality Improvement of the Mediterranean Fruit Fly, Ceratitis capitata Wied 1- Measured by using dehydrogenase Enzyme Activities

International Nuclear Information System (INIS)

Salama, M.S.; Shoman, A.A.; Elbermawy, S.M.; Abul Yazid, I.

2000-01-01

The present study searches for the improvement vitality of the Mediterranean fruit fly, Ceratitis capitata Wied. Through the induction of a specific variance (mutation) in the genetic material. Several types of treatments that were thought to cause this mutation were used, as IGR's, temperature, formaldehyde, colchicine, alcohols, several types of larval rearing media and gamma-rays. Generally, the activities of the energy enzymes alpha-glycerophosphate dehydrogenase (alpha-GPDH) enzyme lactate dehydrogenase (LDH) enzyme and malate dehydrogenase (MDH) enzyme, when used as a direct measure for the fly vitality, increased due to treatments of the egg stage by the previously mentioned treatments specially by the usage of rice hulls in the larval rearing medium alone or followed by irradiation of the pupal stage with 90 Gy

Exercise-induced pyruvate dehydrogenase activation is not affected by 7 days of bed rest

DEFF Research Database (Denmark)

Kiilerich, Kristian; Jørgensen, Stine Ringholm; Biensø, Rasmus Sjørup

2011-01-01

To test the hypothesis that physical inactivity impairs the exercise-induced modulation of pyruvate dehydrogenase (PDH), 6 healthy normally physically active male subjects completed 7 days of bed rest. Before and immediately after the bed rest, the subjects completed an OGTT and a one-legged knee...

EPA, DHA, and Lipoic Acid Differentially Modulate the n-3 Fatty Acid Biosynthetic Pathway in Atlantic Salmon Hepatocytes.

Science.gov (United States)

Bou, Marta; Østbye, Tone-Kari; Berge, Gerd M; Ruyter, Bente

2017-03-01

The aim of the present study was to investigate how EPA, DHA, and lipoic acid (LA) influence the different metabolic steps in the n-3 fatty acid (FA) biosynthetic pathway in hepatocytes from Atlantic salmon fed four dietary levels (0, 0.5, 1.0 and 2.0%) of EPA, DHA or a 1:1 mixture of these FA. The hepatocytes were incubated with [1- 14 C] 18:3n-3 in the presence or absence of LA (0.2 mM). Increased endogenous levels of EPA and/or DHA and LA exposure both led to similar responses in cells with reduced desaturation and elongation of [1- 14 C] 18:3n-3 to 18:4n-3, 20:4n-3, and EPA, in agreement with reduced expression of the Δ6 desaturase gene involved in the first step of conversion. DHA production, on the other hand, was maintained even in groups with high endogenous levels of DHA, possibly due to a more complex regulation of this last step in the n-3 metabolic pathway. Inhibition of the Δ6 desaturase pathway led to increased direct elongation to 20:3n-3 by both DHA and LA. Possibly the route by 20:3n-3 and then Δ8 desaturation to 20:4n-3, bypassing the first Δ6 desaturase step, can partly explain the maintained or even increased levels of DHA production. LA increased DHA production in the phospholipid fraction of hepatocytes isolated from fish fed 0 and 0.5% EPA and/or DHA, indicating that LA has the potential to further increase the production of this health-beneficial FA in fish fed diets with low levels of EPA and/or DHA.

STUDIES ON THE DYNAMICS OF DEHYDROGENASES KREBS CYCLE ACTIVITY AT MONILINIA LAXA (ADERH. & RUHL. HONEY FUNGUS GROWN ON MEDIA WITH DIFFERENT CARBOHYDRATES

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Elena Ciornea

2010-09-01

Full Text Available As ubiquitous organisms, fungi grow on a large number of organic substrate, alive or dead, confronting therefore with a wide variety of carbohydrates and various physical factors, and their versatility to adapt and be able to use a large number of these compounds could provide them the chance to survive. Given that, these fungi have a rich enzyme equipment that allows them to operate on different metabolic pathways, this study aims to monitor the dynamics activity of some Krebs cycle dehydrogenases in Monilinia laxa (Aderh & Ruhl. Honey species parasitic on various species of plum trees. To this end, the fungus was cultivated in vitro on media enriched with different carbohydrates and the isocitrate dehydrogenase, �-cetoglutarate dehydrogenase, succinate dehydrogenase and malate dehydrogenase activity in the fungus mycelium was followed, at 7, respectively, 14 days after the inoculation of the culture medium and determined using the spectrophotometric Sîsoev and Krasna method (Cojocaru, D.C., 2009. Data revealed obvious differences depending on the type of carbohydrate introduced into the medium and the age of the culture mycelia.

STUDIES ON THE DYNAMICS OF DEHYDROGENASES KREBS CYCLE ACTIVITY AT MONILINIA LAXA (ADERH. & RUHL. HONEY FUNGUS GROWN ON MEDIA WITH DIFFERENT CARBOHYDRATES

Directory of Open Access Journals (Sweden)

Elena Ciornea

2011-11-01

Full Text Available As ubiquitous organisms, fungi grow on a large number of organic substrate, alive or dead, confronting therefore with a wide variety of carbohydrates and various physical factors, and their versatility to adapt and be able to use a large number of these compounds could provide them the chance to survive. Given that, these fungi have a rich enzyme equipment that allows them to operate on different metabolic pathways, this study aims to monitor the dynamics activity of some Krebs cycle dehydrogenases in Monilinia laxa (Aderh & Ruhl. Honey species parasitic on various species of plum trees. To this end, the fungus was cultivated in vitro on media enriched with different carbohydrates and the isocitrate dehydrogenase, �-cetoglutarate dehydrogenase, succinate dehydrogenase and malate dehydrogenase activity in the fungus mycelium was followed, at 7, respectively, 14 days after the inoculation of the culture medium and determined using the spectrophotometric Sîsoev and Krasna method (Cojocaru, D.C., 2009. Data revealed obvious differences depending on the type of carbohydrate introduced into the medium and the age of the culture mycelia.

Chemopreventive and renal protective effects for docosahexaenoic acid (DHA: implications of CRP and lipid peroxides

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Darweish MM

2009-04-01

Full Text Available Abstract Background The fish oil-derived ω-3 fatty acids, like docosahexanoic (DHA, claim a plethora of health benefits. We currently evaluated the antitumor effects of DHA, alone or in combination with cisplatin (CP in the EAC solid tumor mice model, and monitored concomitant changes in serum levels of C-reactive protein (CRP, lipid peroxidation (measured as malondialdehyde; MDA and leukocytic count (LC. Further, we verified the capacity of DHA to ameliorate the lethal, CP-induced nephrotoxicity in rats and the molecular mechanisms involved therein. Results EAC-bearing mice exhibited markedly elevated LC (2-fold, CRP (11-fold and MDA levels (2.7-fold. DHA (125, 250 mg/kg elicited significant, dose-dependent reductions in tumor size (38%, 79%; respectively, as well as in LC, CRP and MDA levels. These effects for CP were appreciably lower than those of DHA (250 mg/kg. Interestingly, DHA (125 mg/kg markedly enhanced the chemopreventive effects of CP and boosted its ability to reduce serum CRP and MDA levels. Correlation studies revealed a high degree of positive association between tumor growth and each of CRP (r = 0.85 and leukocytosis (r = 0.89, thus attesting to a diagnostic/prognostic role for CRP. On the other hand, a single CP dose (10 mg/kg induced nephrotoxicity in rats that was evidenced by proteinuria, deterioration of glomerular filtration rate (GFR, -4-fold, a rise in serum creatinine/urea levels (2–5-fold after 4 days, and globally-induced animal fatalities after 7 days. Kidney-homogenates from CP-treated rats displayed significantly elevated MDA- and TNF-α-, but reduced GSH-, levels. Rats treated with DHA (250 mg/kg, but not 125 mg/kg survived the lethal effects of CP, and showed a significant recovery of GFR; while their homogenates had markedly-reduced MDA- and TNF-α-, but -increased GSH-levels. Significant association was detected between creatinine level and those of MDA (r = 0.81, TNF-α r = 0.92 and GSH (r = -0

A Correlation Study of DHA Intake Estimated by a FFQ and Concentrations in Plasma and Erythrocytes in Mid- and Late Pregnancy

Science.gov (United States)

Zhou, Yu-Bo; Li, Hong-Tian; Trasande, Leonardo; Wang, Lin-Lin; Zhang, Ya-Li; Si, Ke-Yi; Bai, Man-Xi; Liu, Jian-Meng

2017-01-01

Adequate docosahexaenoic acid (DHA) is essential for the optimal growth and development of the fetus. Maternal DHA content fluctuates during pregnancy. The correlation of DHA content with dietary intake might be varied over the course of pregnancy. We aimed to compare the dietary DHA intake, estimated by a DHA-specific semiquantitative food frequency questionnaire (FFQ) against its blood content, among mid- and late-term pregnant women. A total of 804 Chinese pregnant women completed the tailored FFQ and provided fasting venous blood samples. Dietary DHA intake (mg/day) in the previous month was calculated from the FFQ using Chinese Food Composition Table. DHA concentrations (weight percent of total fatty acids) in plasma and erythrocytes were measured by capillary gas chromatography. Spearman correlation coefficients (rs) between DHA intake and its relative concentrations were calculated. After adjustment for maternal age, pre-pregnancy body mass index, stage of pregnancy, parity, education level, ethnicity, and annual family income per capita, the correlation coefficients of DHA intake with its concentrations in plasma and erythrocytes were 0.35 and 0.33, respectively (p DHA intake and its plasma or erythrocytes concentrations (p DHA intake, estimated by the FFQ, was positively correlated with its concentrations in plasma and erythrocytes in Chinese pregnant women, especially for women in late pregnancy, with the exception of the erythrocytes of those living in a coastland area. PMID:29144430

17 beta-hydroxysteroid dehydrogenase activity in canine pancreas

International Nuclear Information System (INIS)

Mendoza-Hernandez, G.; Lopez-Solache, I.; Rendon, J.L.; Diaz-Sanchez, V.; Diaz-Zagoya, J.C.

1988-01-01

The mitochondrial fraction of the dog pancreas showed NAD(H)-dependent enzyme activity of 17 beta-hydroxysteroid dehydrogenase. The enzyme catalyzes oxidoreduction between androstenedione and testosterone. The apparent Km value of the enzyme for androstenedione was 9.5 +/- 0.9 microM, the apparent Vmax was determined as 0.4 nmol mg-1 min-1, and the optimal pH was 6.5. In phosphate buffer, pH 7.0, maximal rate of androstenedione reduction was observed at 37 degrees C. The oxidation of testosterone by the enzyme proceeded at the same rate as the reduction of the androstenedione at a pH of 6.8-7.0. The apparent Km value and the optimal pH of the enzyme for testosterone were 3.5 +/- 0.5 microM and 7.5, respectively

Maternal DHA Status during Pregnancy Has a Positive Impact on Infant Problem Solving: A Norwegian Prospective Observation Study

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Hanne Cecilie Braarud

2018-04-01

Full Text Available Docosahexaenoic acid (DHA, 22:6, n-3 is a long-chain polyunsaturated fatty acid necessary for normal brain growth and cognitive development. Seafood and dietary supplements are the primary dietary sources of DHA. This study addresses the associations between DHA status in pregnant women and healthy, term-born infant problem-solving skills assessed using the Ages and Stages Questionnaire. The fatty acid status of maternal red blood cells (RBCs was assessed in the 28th week of gestation and at three months postpartum. The infants’ fatty acid status (RBC was assessed at three, six, and twelve months, and problem-solving skills were assessed at six and twelve months. Maternal DHA status in pregnancy was found to be positively associated with infants’ problem-solving skills at 12 months. This association remained significant even after controlling for the level of maternal education, a surrogate for socio-economic status. The infants’ DHA status at three months was associated with the infants’ problem solving at 12 months. The results accentuate the importance for pregnant and lactating women to have a satisfactory DHA status from dietary intake of seafood or other sources rich in DHA.

Maternal DHA Status during Pregnancy Has a Positive Impact on Infant Problem Solving: A Norwegian Prospective Observation Study.

Science.gov (United States)

Braarud, Hanne Cecilie; Markhus, Maria Wik; Skotheim, Siv; Stormark, Kjell Morten; Frøyland, Livar; Graff, Ingvild Eide; Kjellevold, Marian

2018-04-24

Docosahexaenoic acid (DHA, 22:6, n -3) is a long-chain polyunsaturated fatty acid necessary for normal brain growth and cognitive development. Seafood and dietary supplements are the primary dietary sources of DHA. This study addresses the associations between DHA status in pregnant women and healthy, term-born infant problem-solving skills assessed using the Ages and Stages Questionnaire. The fatty acid status of maternal red blood cells (RBCs) was assessed in the 28th week of gestation and at three months postpartum. The infants’ fatty acid status (RBC) was assessed at three, six, and twelve months, and problem-solving skills were assessed at six and twelve months. Maternal DHA status in pregnancy was found to be positively associated with infants’ problem-solving skills at 12 months. This association remained significant even after controlling for the level of maternal education, a surrogate for socio-economic status. The infants’ DHA status at three months was associated with the infants’ problem solving at 12 months. The results accentuate the importance for pregnant and lactating women to have a satisfactory DHA status from dietary intake of seafood or other sources rich in DHA.

Evaluation of Serum Lactate Dehydrogenase Activity in a Virtual Environment

Directory of Open Access Journals (Sweden)

V.M.T. Trindade

2013-05-01

Full Text Available Introduction: Lactate dehydrogenase is a citosolic enzyme involved in reversible transformation of pyruvate to lactate. It participates in anaerobic glycolysis of skeletal muscle and red blood cells, in liver gluconeogenesis and in aerobic metabolism of heart muscle. The determination of its activity helps in the diagnosis of various diseases, because it is increased in serum of patients suffering from myocardial infarction, acute hepatitis, muscular dystrophy and cancer. This paper presents a learning object, mediated by computer, which contains the simulation of the laboratory determination serum lactate dehydrogenase activity measured by the spectrophotometric method, based in the decrease of absorbance at 340 nm. Materials and Methods: Initially, pictures and videos were obtained recording the procedure of the methodology. The most representative images were selected, edited and inserted into an animation developed with the aid of the tool Adobe ® Flash ® CS3. The validation of the object was performed by the students of Biochemistry I (Pharmacy-UFRGS from the second semester of 2009 and both of 2010. Results and Discussion: The analysis of students' answers revealed that 80% attributed the excellence of the navigation program, the display format and to aid in learning. Conclusion: Therefore, this software can be considered an adequate teaching resource as well as an innovative support in the construction of theoretical and practical knowledge of Biochemistry. Available at: http://www6.ufrgs.br/gcoeb/LDH

The effects of aspirin on platelet function and lysophosphatidic acids depend on plasma concentrations of EPA and DHA.

Science.gov (United States)

Block, Robert C; Abdolahi, Amir; Tu, Xin; Georas, Steve N; Brenna, J Thomas; Phipps, Richard P; Lawrence, Peter; Mousa, Shaker A

2015-05-01

Aspirin's prevention of cardiovascular disease (CVD) events in individuals with type 2 diabetes mellitus is controversial. Eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) and aspirin all affect the cyclooxygenase enzyme. The relationship between plasma EPA and DHA and aspirin's effects has not been determined. Thirty adults with type 2 diabetes mellitus ingested aspirin (81 mg/day) for 7 days, then EPA+DHA (2.6g/day) for 28 days, then both for another 7 days. Lysophosphatidic acid (LPA) species and more classic platelet function outcomes were determined. Plasma concentrations of total EPA+DHA were associated with 7-day aspirin reduction effects on these outcomes in a "V"-shaped manner for all 11 LPA species and ADP-induced platelet aggregation. This EPA+DHA concentration was quite consistent for each of the LPA species and ADP. These results support aspirin effects on lysolipid metabolism and platelet aggregation depending on plasma EPA+DHA concentrations in individuals with a disturbed lipid milieu. Copyright © 2014 Elsevier Ltd. All rights reserved.

Enhancement of docosahexaenoic acid (DHA) production from Schizochytrium sp. S31 using different growth medium conditions.

Science.gov (United States)

Sahin, Deniz; Tas, Ezgi; Altindag, Ulkü Hüma

2018-01-24

Schizochytrium species is one of the most studied microalgae for production of docosahexaenoic acid (DHA) which is an omega-3 fatty acid with positive effects for human health. However, high cost and low yield in production phase makes optimization of cultivation process inevitable. We focus on the optimization of DHA production using Schizochytrium sp. using different media supplements; glucose, fructose and glycerol as carbon variants, proteose peptone and tryptone as nitrogen variants. The highest biomass (5.61 g/L) and total fatty acid yield (1.74 g/L) were obtained in proteose peptone medium which was used as the alternative nitrogen source instead of yeast extract. The highest DHA yield (0.40 g/L) was achieved with glycerol as the carbon source although it had the second lowest biomass production after ethanol containing medium. Ethanol, as an alternative carbon source and a precursor for acetyl-CoA, increased DHA percentage in total lipid content from 29.94 to 40.04% but decreasing the biomass drastically. Considering different carbon and nitrogen sources during cultivation of Schizochytrium sp. will improve DHA production. Combination of proteose peptone and glycerol as nitrogen and carbon sources, respectively, and addition of ethanol with a proper timing will be useful to have higher DHA yield.

Physiological and fermentation properties of Bacillus coagulans and a mutant lacking fermentative lactate dehydrogenase activity.

Science.gov (United States)

Su, Yue; Rhee, Mun Su; Ingram, Lonnie O; Shanmugam, K T

2011-03-01

Bacillus coagulans, a sporogenic lactic acid bacterium, grows optimally at 50-55 °C and produces lactic acid as the primary fermentation product from both hexoses and pentoses. The amount of fungal cellulases required for simultaneous saccharification and fermentation (SSF) at 55 °C was previously reported to be three to four times lower than for SSF at the optimum growth temperature for Saccharomyces cerevisiae of 35 °C. An ethanologenic B. coagulans is expected to lower the cellulase loading and production cost of cellulosic ethanol due to SSF at 55 °C. As a first step towards developing B. coagulans as an ethanologenic microbial biocatalyst, activity of the primary fermentation enzyme L-lactate dehydrogenase was removed by mutation (strain Suy27). Strain Suy27 produced ethanol as the main fermentation product from glucose during growth at pH 7.0 (0.33 g ethanol per g glucose fermented). Pyruvate dehydrogenase (PDH) and alcohol dehydrogenase (ADH) acting in series contributed to about 55% of the ethanol produced by this mutant while pyruvate formate lyase and ADH were responsible for the remainder. Due to the absence of PDH activity in B. coagulans during fermentative growth at pH 5.0, the l-ldh mutant failed to grow anaerobically at pH 5.0. Strain Suy27-13, a derivative of the l-ldh mutant strain Suy27, that produced PDH activity during anaerobic growth at pH 5.0 grew at this pH and also produced ethanol as the fermentation product (0.39 g per g glucose). These results show that construction of an ethanologenic B. coagulans requires optimal expression of PDH activity in addition to the removal of the LDH activity to support growth and ethanol production.

(n-3) fatty acids and cardiovascular health: are effects of EPA and DHA shared or complementary?

Science.gov (United States)

Mozaffarian, Dariush; Wu, Jason H Y

2012-03-01

Considerable research supports cardiovascular benefits of consuming omega-3 PUFA, also known as (n-3) PUFA, from fish or fish oil. Whether individual long-chain (n-3) PUFA have shared or complementary effects is not well established. We reviewed evidence for dietary and endogenous sources and cardiovascular effects on biologic pathways, physiologic risk factors, and clinical endpoints of EPA [20:5(n-3)], docosapentaenoic acid [DPA, 22:5(n-3)], and DHA [22:6(n-3)]. DHA requires direct dietary consumption, with little synthesis from or retroconversion to DPA or EPA. Whereas EPA is also largely derived from direct consumption, EPA can also be synthesized in small amounts from plant (n-3) precursors, especially stearidonic acid. In contrast, DPA appears principally derived from endogenous elongation from EPA, and DPA can also undergo retroconversion back to EPA. In experimental and animal models, both EPA and DHA modulate several relevant biologic pathways, with evidence for some differential benefits. In humans, both fatty acids lower TG levels and, based on more limited studies, favorably affect cardiac diastolic filling, arterial compliance, and some metrics of inflammation and oxidative stress. All three (n-3) PUFA reduce ex vivo platelet aggregation and DHA also modestly increases LDL and HDL particle size; the clinical relevance of such findings is uncertain. Combined EPA+DHA or DPA+DHA levels are associated with lower risk of fatal cardiac events and DHA with lower risk of atrial fibrillation, suggesting direct or indirect benefits of DHA for cardiac arrhythmias (although not excluding similar benefits of EPA or DPA). Conversely, EPA and DPA, but not DHA, are associated with lower risk of nonfatal cardiovascular endpoints in some studies, and purified EPA reduced risk of nonfatal coronary syndromes in one large clinical trial. Overall, for many cardiovascular pathways and outcomes, identified studies of individual (n-3) PUFA were relatively limited, especially

Cloning and expression analysis of alcohol dehydrogenase ( Adh ...

African Journals Online (AJOL)

Hybrid promoters are created by shuffling of DNA fragments while keeping intact regulatory regions crucial of promoter activity. Two fragments of alcohol dehydrogenase (Adh) promoter from Zea mays were selected to generate hybrid promoter. Sequence analysis of both alcohol dehydrogenase promoter fragments through ...

Pronounced between-subject and circadian variability in thymidylate synthase and dihydropyrimidine dehydrogenase enzyme activity in human volunteers

NARCIS (Netherlands)

Jacobs, Bart A W; Deenen, Maarten J; Pluim, Dick; van Hasselt, J G Coen; Krähenbühl, Martin D; van Geel, Robin M J M; de Vries, Niels; Rosing, Hilde; Meulendijks, Didier; Burylo, Artur M; Cats, Annemieke; Beijnen, Jos H; Huitema, Alwin D R; Schellens, Jan H M

AIMS: The enzymatic activity of dihydropyrimidine dehydrogenase (DPD) and thymidylate synthase (TS) are important for the tolerability and efficacy of the fluoropyrimidine drugs. In the present study, we explored between-subject variability (BSV) and circadian rhythmicity in DPD and TS activity in

The oxidized form of vitamin C, dehydroascorbic acid, regulates neuronal energy metabolism.

Science.gov (United States)

Cisternas, Pedro; Silva-Alvarez, Carmen; Martínez, Fernando; Fernandez, Emilio; Ferrada, Luciano; Oyarce, Karina; Salazar, Katterine; Bolaños, Juan P; Nualart, Francisco

2014-05-01

Vitamin C is an essential factor for neuronal function and survival, existing in two redox states, ascorbic acid (AA), and its oxidized form, dehydroascorbic acid (DHA). Here, we show uptake of both AA and DHA by primary cultures of rat brain cortical neurons. Moreover, we show that most intracellular AA was rapidly oxidized to DHA. Intracellular DHA induced a rapid and dramatic decrease in reduced glutathione that was immediately followed by a spontaneous recovery. This transient decrease in glutathione oxidation was preceded by an increase in the rate of glucose oxidation through the pentose phosphate pathway (PPP), and a concomitant decrease in glucose oxidation through glycolysis. DHA stimulated the activity of glucose-6-phosphate dehydrogenase, the rate-limiting enzyme of the PPP. Furthermore, we found that DHA stimulated the rate of lactate uptake by neurons in a time- and dose-dependent manner. Thus, DHA is a novel modulator of neuronal energy metabolism by facilitating the utilization of glucose through the PPP for antioxidant purposes. © 2014 International Society for Neurochemistry.

EFFECTS OF AMARANTHS’ SEEDS ON DEHYDROGENASE ACTIVITY AND GASES EMISSION IN METHANOGENIC BIOREACTORS

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Victor COVALIOV

2015-12-01

Full Text Available The influence of amaranths‘ seeds as the source of squalene on the dehydrogenase activity and efficiency of methane production were investigated in methanogenic bench-scale (5000 ml bioreactors used to treat the mixture of distillery wastes and farmyard manure. The adding of amaranth seeds to the methanogenic bioreactor has an inhibitory effect on the dehydrogenase activity and stimulates the process of methanogenesis. Dehydrogenase activity decreased with the increase of doses of squalene and its trend had a close connection with doses (R2=0.77-0.78. The methane content in the total amount of gases is 65.3-71.3% in a bioreactor with the additive of amaranth seeds in a dose of 50 mg l-1, which is 22.1% higher than in the the control bioreactor without additives. The increase in squalene concentration higher than 0.0005% is not rational because its stimulating effect on the methanogenic process decreases. Anaerobic digestion of alcohol distillery industry wastes with manure is a complex nonlinear time-varying microbiological process. Dehydrogenase activity trends in the experiment are described by the power function for 5 hours observations and by the logarithmic function for 120 hours of observations. Trends of CH4 are described by the polynomial function in all periods of testing. Correlation coefficients are 0.37 and 0.70 for CH4 after 5 and 120 hours of the anaerobic digestion. Dehydrogenase activity is in the close negative connection with the amount of gases, including methane. Correlation analysis between dehydrogenase activity and the release of gases has revealed the moderate and strongly negative link during 24 hours after the start of the experiment.EFECTUL SEMINŢELOR DE AMARANT ASUPRA ACTIVITĂŢII DEHIDROGENAZEI ŞI EMISIEI GAZELOR ÎN BIOREACTOARELE METANOGENEÎn bioreactoare metanogene unite consecutiv, cu volum de 5000 ml, utilizate pentru tratarea amestecului de borhot de la distilarea alcoolului cu gunoi de grajd, a fost

The roles of different salts and a novel osmotic pressure control strategy for improvement of DHA production by Schizochytrium sp.

Science.gov (United States)

Hu, Xue-Chao; Ren, Lu-Jing; Chen, Sheng-Lan; Zhang, Li; Ji, Xiao-Jun; Huang, He

2015-11-01

The effects of different osmotic pressure, changed by six salts (NaCl, Na2SO4, (NH4)2SO4, KH2PO4 and MSG), on cell growth and DHA synthesis by Schizochytrium sp. were investigated. Six optimal mediums were obtained to study different osmotic pressure combinations at cell growth stage and DHA synthesis stage. Results showed that cultivated cell in higher osmotic pressure condition and fermented in lower osmotic pressure condition was benefit to enhance DHA synthesis. Combination 17-6 could get the maximum cell dry weight of 56.95 g/L and the highest DHA percentage in total fatty acids of 55.21%, while combination 17-B could get the highest lipid yield of 33.47 g/L with 42.10% DHA in total fatty acids. This was the first report about the enhancement of DHA production by osmotic regulation and this work provided two novel osmotic control processes for high lipid yield and high DHA percentage in total fatty acids.

Phosphorylation site on yeast pyruvate dehydrogenase complex

International Nuclear Information System (INIS)

Uhlinger, D.J.

1986-01-01

The pyruvate dehydrogenase complex was purified to homogeneity from baker's yeast (Saccharomyces cerevisiae). Yeast cells were disrupted in a Manton-Gaulin laboratory homogenizer. The pyruvate dehydrogenase complex was purified by fractionation with polyethylene glycol, isoelectric precipitation, ultracentrifugation and chromatography on hydroxylapatite. Final purification of the yeast pyruvate dehydrogenase complex was achieved by cation-exchange high pressure liquid chromatography (HPLC). No endogenous pyruvate dehydrogenase kinase activity was detected during the purification. However, the yeast pyruvate dehydrogenase complex was phosphorylated and inactivated with purified pyruvate dehydrogenase kinase from bovine kidney. Tryptic digestion of the 32 P-labeled complex yielded a single phosphopeptide which was purified to homogeniety. The tryptic digest was subjected to chromatography on a C-18 reverse phase HPLC column with a linear gradient of acetonitrile. Radioactive fractions were pooled, concentrated, and subjected to anion-exchange HPLC. The column was developed with a linear gradient of ammonium acetate. Final purification of the phosphopeptide was achieved by chromatography on a C-18 reverse phase HPLC column developed with a linear gradient of acetonitrile. The amino acid sequence of the homogeneous peptide was determined by manual modified Edman degradation

Some Properties of Glutamate Dehydrogenase from the Marine Red ...

African Journals Online (AJOL)

Keywords: ammonia assimilation, glutamate dehydrogenase, GDH, Gracilaria sordida, red alga, enzyme activity. Glutamate dehydrogenases (GDH, EC ... Anabolic functions could be assimilation of ammonia released during photorespiration and synthesis of N-rich transport compounds. Western Indian Ocean Journal of ...

STUDY ON THE THERMAL STABILITY OF EPA AND DHA IN MUJAHIR (Oreochromis mossambicus FISH OIL

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Ngatidjo Hadipranoto

2010-06-01

Full Text Available EPA (Eicosapentaenoic acid and DHA (Docosahexaenoic acid content in common fresh water fish : mujahir (Oreochromis mossambicus after indirect heating were analysed. The aims of this study were to determine the effect of indirect heating process and α-tocopherol additions on both fatty acid stability.Lipids content in the mujahir fillets were extracted by Folch method using chloroform-metanol (2:1 mixture. Fatty acids in fish oil were converted to fatty acid methyl esters and then injected into gas chromatography to determine the EPA and DHA concentration. Operating condition of gas chromatography were programmed as follows: injection port temperature at 270 oC, detector at 280 oC, initial column temperature at 200 oC, and the final at 280 oC, the carrier gas was helium with flow rate of 10 ml per minute and temperature of column was increased gradually at 10 oC per minute. The effect of α-tocopherol addition on the stability of EPA and DHA was studied by adding α-tocopherol at 50 to 200 mg per kilogram sample before indirect heating process was carried out.The analysis of mujahir fish oil showed that the content of EPA and DHA in 100 grams fresh sample was 105 and 406,5 mg respectivelly. Indirect heating caused the EPA and DHA content decreased significantly. The addition of α-tocopherol results in a positive corelation between α-tocopherol concentration added and the decrease of EPA and DHA content during the heating process.   Keywords: fatty acid, eicosapentaenoic acid, docosahexaenoic acid

The activity state of the branched-chain 2-oxo acid dehydrogenase complex in rat tissues.

OpenAIRE

Wagenmakers, A J; Schepens, J T; Veldhuizen, J A; Veerkamp, J H

1984-01-01

An assay is described to define the proportion of the branched-chain 2-oxo acid dehydrogenase complex that is present in the active state in rat tissues. Activities are measured in homogenates in two ways: actual activities, present in tissues, by blocking both the kinase and phosphatase of the enzyme complex during homogenization, preincubation, and incubation with 1-14C-labelled branched-chain 2-oxo acid, and total activities by blocking only the kinase during the 5 min preincubation (neces...

On the potential application of polar and temperate marine microalgae for EPA and DHA production

NARCIS (Netherlands)

Boelen, P.; van Dijk, R.; Sinninghe Damsté, J.S.; Rijpstra, W.I.C.; Buma, A.G.J.

2013-01-01

Long chain polyunsaturated fatty acids (LC-PUFAs) such as eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) are considered essential omega-3 fatty acids in human nutrition. In marine microalgae EPA and/or DHA are allegedly involved in the regulation of membrane fluidity and thylakoid

Effects of Al(III and Nano-Al13 Species on Malate Dehydrogenase Activity

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Rong Fu Chen

2011-05-01

Full Text Available The effects of different aluminum species on malate dehydrogenase (MDH activity were investigated by monitoring amperometric i-t curves for the oxidation of NADH at low overpotential using a functionalized multi-wall nanotube (MWNT modified glass carbon electrode (GCE. The results showed that Al(III and Al13 can activate the enzymatic activity of MDH, and the activation reaches maximum levels as the Al(III and Al13 concentration increase. Our study also found that the effects of Al(III and Al13 on the activity of MDH depended on the pH value and aluminum speciation. Electrochemical and circular dichroism spectra methods were applied to study the effects of nano-sized aluminum compounds on biomolecules.

Effects of Al(III) and nano-Al13 species on malate dehydrogenase activity.

Science.gov (United States)

Yang, Xiaodi; Cai, Ling; Peng, Yu; Li, Huihui; Chen, Rong Fu; Shen, Ren Fang

2011-01-01

The effects of different aluminum species on malate dehydrogenase (MDH) activity were investigated by monitoring amperometric i-t curves for the oxidation of NADH at low overpotential using a functionalized multi-wall nanotube (MWNT) modified glass carbon electrode (GCE). The results showed that Al(III) and Al(13) can activate the enzymatic activity of MDH, and the activation reaches maximum levels as the Al(III) and Al(13) concentration increase. Our study also found that the effects of Al(III) and Al(13) on the activity of MDH depended on the pH value and aluminum speciation. Electrochemical and circular dichroism spectra methods were applied to study the effects of nano-sized aluminum compounds on biomolecules.

Omega-3 free fatty acids suppress macrophage inflammasome activation by inhibiting NF-κB activation and enhancing autophagy.

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Yolanda Williams-Bey

Full Text Available The omega-3 (ω3 fatty acid docosahexaenoic acid (DHA can suppress inflammation, specifically IL-1β production through poorly understood molecular mechanisms. Here, we show that DHA reduces macrophage IL-1β production by limiting inflammasome activation. Exposure to DHA reduced IL-1β production by ligands that stimulate the NLRP3, AIM2, and NAIP5/NLRC4 inflammasomes. The inhibition required Free Fatty Acid Receptor (FFAR 4 (also known as GPR120, a G-protein coupled receptor (GPR known to bind DHA. The exposure of cells to DHA recruited the adapter protein β-arrestin1/2 to FFAR4, but not to a related lipid receptor. DHA treatment reduced the initial inflammasome priming step by suppressing the nuclear translocation of NF-κB. DHA also reduced IL-1β levels by enhancing autophagy in the cells. As a consequence macrophages derived from mice lacking the essential autophagy protein ATG7 were partially resistant to suppressive effects of DHA. Thus, DHA suppresses inflammasome activation by two distinct mechanisms, inhibiting the initial priming step and by augmenting autophagy, which limits inflammasome activity.

Active site of Zn2+-dependent sn-glycerol-1-phosphate dehydrogenase from Aeropyrum pernix K1

Directory of Open Access Journals (Sweden)

Jin-Suk Han

2005-01-01

Full Text Available The enzyme sn-glycerol-1-phosphate dehydrogenase (Gro1PDH, EC 1.1.1.261 is key to the formation of the enantiomeric configuration of the glycerophosphate backbone (sn-glycerol-1-phosphate of archaeal ether lipids. This enzyme catalyzes the reversible conversion between dihydroxyacetone phosphate and glycerol-1-phosphate. To date, no information about the active site and catalytic mechanism of this enzyme has been reported. Using the sequence and structural information for glycerol dehydrogenase, we constructed six mutants (D144N, D144A, D191N, H271A, H287A and D191N/H271A of Gro1PDH from Aeropyrum pernix K1 and examined their characteristics to clarify the active site of this enzyme. The enzyme was found to be a zinc-dependent metalloenzyme, containing one zinc ion for every monomer protein that was essential for activity. Site-directed mutagenesis of D144 increased the activity of the enzyme. Mutants D144N and D144A exhibited low affinity for the substrates and higher activity than the wild type, but their affinity for the zinc ion was the same as that of the wild type. Mutants D191N, H271A and H287A had a low affinity for the zinc ion and a low activity compared with the wild type. The double mutation, D191N/ H271A, had no enzyme activity and bound no zinc. From these results, it was clarified that residues D191, H271 and H287 participate in the catalytic activity of the enzyme by binding the zinc ion, and that D144 has an effect on substrate binding. The structure of the active site of Gro1PDH from A. pernix K1 seems to be similar to that of glycerol dehydrogenase, despite the differences in substrate specificity and biological role.

Dietary DHA supplementation in an APP/PS1 transgenic rat model of AD reduces behavioral and Aβ pathology and modulates Aβ oligomerization.

Science.gov (United States)

Teng, Edmond; Taylor, Karen; Bilousova, Tina; Weiland, David; Pham, Thaidan; Zuo, Xiaohong; Yang, Fusheng; Chen, Ping-Ping; Glabe, Charles G; Takacs, Alison; Hoffman, Dennis R; Frautschy, Sally A; Cole, Gregory M

2015-10-01

Increased dietary consumption of docosahexaenoic acid (DHA) is associated with decreased risk for Alzheimer's disease (AD). These effects have been postulated to arise from DHA's pleiotropic effects on AD pathophysiology, including its effects on β-amyloid (Aβ) production, aggregation, and toxicity. While in vitro studies suggest that DHA may inhibit and reverse the formation of toxic Aβ oligomers, it remains uncertain whether these mechanisms operate in vivo at the physiological concentrations of DHA attainable through dietary supplementation. We sought to clarify the effects of dietary DHA supplementation on Aβ indices in a transgenic APP/PS1 rat model of AD. Animals maintained on a DHA-supplemented diet exhibited reductions in hippocampal Aβ plaque density and modest improvements on behavioral testing relative to those maintained on a DHA-depleted diet. However, DHA supplementation also increased overall soluble Aβ oligomer levels in the hippocampus. Further quantification of specific conformational populations of Aβ oligomers indicated that DHA supplementation increased fibrillar (i.e. putatively less toxic) Aβ oligomers and decreased prefibrillar (i.e. putatively more toxic) Aβ oligomers. These results provide in vivo evidence suggesting that DHA can modulate Aβ aggregation by stabilizing soluble fibrillar Aβ oligomers and thus reduce the formation of both Aβ plaques and prefibrillar Aβ oligomers. However, since fibrillar Aβ oligomers still retain inherent neurotoxicity, DHA may need to be combined with other interventions that can additionally reduce fibrillar Aβ oligomer levels for more effective prevention of AD in clinical settings. Published by Elsevier Inc.

(n-3) Fatty Acids and Cardiovascular Health: Are Effects of EPA and DHA Shared or Complementary?123

Science.gov (United States)

Mozaffarian, Dariush; Wu, Jason H. Y.

2012-01-01

Considerable research supports cardiovascular benefits of consuming omega-3 PUFA, also known as (n-3) PUFA, from fish or fish oil. Whether individual long-chain (n-3) PUFA have shared or complementary effects is not well established. We reviewed evidence for dietary and endogenous sources and cardiovascular effects on biologic pathways, physiologic risk factors, and clinical endpoints of EPA [20:5(n-3)], docosapentaenoic acid [DPA, 22:5(n-3)], and DHA [22:6(n-3)]. DHA requires direct dietary consumption, with little synthesis from or retroconversion to DPA or EPA. Whereas EPA is also largely derived from direct consumption, EPA can also be synthesized in small amounts from plant (n-3) precursors, especially stearidonic acid. In contrast, DPA appears principally derived from endogenous elongation from EPA, and DPA can also undergo retroconversion back to EPA. In experimental and animal models, both EPA and DHA modulate several relevant biologic pathways, with evidence for some differential benefits. In humans, both fatty acids lower TG levels and, based on more limited studies, favorably affect cardiac diastolic filling, arterial compliance, and some metrics of inflammation and oxidative stress. All three (n-3) PUFA reduce ex vivo platelet aggregation and DHA also modestly increases LDL and HDL particle size; the clinical relevance of such findings is uncertain. Combined EPA+DHA or DPA+DHA levels are associated with lower risk of fatal cardiac events and DHA with lower risk of atrial fibrillation, suggesting direct or indirect benefits of DHA for cardiac arrhythmias (although not excluding similar benefits of EPA or DPA). Conversely, EPA and DPA, but not DHA, are associated with lower risk of nonfatal cardiovascular endpoints in some studies, and purified EPA reduced risk of nonfatal coronary syndromes in one large clinical trial. Overall, for many cardiovascular pathways and outcomes, identified studies of individual (n-3) PUFA were relatively limited, especially

Crystallographic analysis of 1,2,3-trichloropropane biodegradation by the haloalkane dehalogenase DhaA31

Czech Academy of Sciences Publication Activity Database

Lahoda, M.; Mesters, J. R.; Stsiapanava, A.; Chaloupková, R.; Kutý, Michal; Damborský, J.; Kutá-Smatanová, Ivana

2014-01-01

Roč. 70, FEB 2014 (2014), s. 209-217 ISSN 0907-4449 Institutional support: RVO:67179843 Keywords : DhaA31 * substrate-free * 3rk4 * complex with TCP * 4fwb * wild-type DhaA * 4hzg Subject RIV: CE - Biochemistry Impact factor: 7.232, year: 2013

The effect of diet and DHA addition on the sensory quality of goat kid meat.

Science.gov (United States)

Moreno-Indias, Isabel; Sánchez-Macías, Davinia; Martínez-de la Puente, Josué; Morales-Delanuez, Antonio; Hernández-Castellano, Lorenzo Enrique; Castro, Noemí; Argüello, Anastasio

2012-02-01

To enhance the nutritional quality of meat, dietary strategies have been developed to manipulate the fatty acid profiles of muscle tissue. Fatty acids affect meat attributes, including hardness, colour and lipid stability, and flavour. Little research has been done, however, on the effects of dietary omega-3 polyunsaturated fatty acid (PUFA) supplementation on the sensory characteristics of meat. To address this issue, six diets were fed to goat kids: goat's milk, powdered whole cow's milk, powdered whole cow's milk plus docosahexaenoic acid (DHA) (low dose), milk replacer, milk replacer plus DHA (low dose), and milk replacer plus DHA (high dose). A descriptive, semi-trained sensory evaluation and a consumer triangular test were performed to analyse the resulting meat. High doses of omega-3 PUFA produced meat with unusual odours, unpleasant flavours, and low overall appreciation scores. Low doses of DHA maintained a positive sensory perception. Copyright © 2011 Elsevier Ltd. All rights reserved.

Impact of carbon and nitrogen feeding strategy on high production of biomass and docosahexaenoic acid (DHA) by Schizochytrium sp. LU310.

Science.gov (United States)

Ling, Xueping; Guo, Jing; Liu, Xiaoting; Zhang, Xia; Wang, Nan; Lu, Yinghua; Ng, I-Son

2015-05-01

A new isolated Schizochytrium sp. LU310 from the mangrove forest of Wenzhou, China, was found as a high producing microalga of docosahexaenoic acid (DHA). In this study, the significant improvements for DHA fermentation by the batch mode in the baffled flasks (i.e. higher oxygen supply) were achieved. By applied the nitrogen-feeding strategy in 1000 mL baffled flasks, the biomass, DHA concentration and DHA productivity were increased by 110.4%, 117.9% and 110.4%, respectively. Moreover, DHA concentration of 21.06 g/L was obtained by feeding 15 g/L of glucose intermittently, which was an increase of 41.25% over that of the batch mode. Finally, an innovative strategy was carried out by intermittent feeding carbon and simultaneously feeding nitrogen. The maximum DHA concentration and DHA productivity in the fed-batch cultivation reached to 24.74 g/L and 241.5 mg/L/h, respectively. Copyright © 2014 Elsevier Ltd. All rights reserved.

ald of Mycobacterium tuberculosis Encodes both the Alanine Dehydrogenase and the Putative Glycine Dehydrogenase

Science.gov (United States)

Giffin, Michelle M.; Modesti, Lucia; Raab, Ronald W.; Wayne, Lawrence G.

2012-01-01

The putative glycine dehydrogenase of Mycobacterium tuberculosis catalyzes the reductive amination of glyoxylate to glycine but not the reverse reaction. The enzyme was purified and identified as the previously characterized alanine dehydrogenase. The Ald enzyme was expressed in Escherichia coli and had both pyruvate and glyoxylate aminating activities. The gene, ald, was inactivated in M. tuberculosis, which resulted in the loss of all activities. Both enzyme activities were found associated with the cell and were not detected in the extracellular filtrate. By using an anti-Ald antibody, the protein was localized to the cell membrane, with a smaller fraction in the cytosol. None was detected in the extracellular medium. The ald knockout strain grew without alanine or glycine and was able to utilize glycine but not alanine as a nitrogen source. Transcription of ald was induced when alanine was the sole nitrogen source, and higher levels of Ald enzyme were measured. Ald is proposed to have several functions, including ammonium incorporation and alanine breakdown. PMID:22210765

An improved method for the assay of platelet pyruvate dehydrogenase

International Nuclear Information System (INIS)

Schofield, P.J.; Griffiths, L.R.; Rogers, S.H.

1980-01-01

An improved method for the assay of human platelet pyruvate dehydrogenase is described. By generating the substrate [1- 14 C]pyruvate in situ from [1- 14 C]lactate plus L-lactate dehydrogenase, the rate of spontaneous decarboxylation is dramatically reduced, allowing far greater sensitivity in the assay of low activities of pyruvate dehydrogenase. In addition, no special precautions are required for the storage and use of [1- 14 C]lactate, in contrast to those for [1- 14 C]pyruvate. These factors allow a 5-10-fold increase in sensitivity compared with current methods. The pyruvate dehydrogenase activity of normal subjects as determined by the [1- 14 C]lactate system was 215+-55 pmol min -1 mg -1 protein (n=18). The advantages of this assay system are discussed. (Auth.)

Prenatal supplementation with DHA improves attention at 5 y of age: a randomized controlled trial.

Science.gov (United States)

Ramakrishnan, Usha; Gonzalez-Casanova, Ines; Schnaas, Lourdes; DiGirolamo, Ann; Quezada, Amado D; Pallo, Beth C; Hao, Wei; Neufeld, Lynnette M; Rivera, Juan A; Stein, Aryeh D; Martorell, Reynaldo

2016-10-01

Docosahexanoic acid (DHA) is an important constituent of the brain. Evidence from well-designed intervention trials of the long-term benefits of increasing DHA intake during pregnancy has been sparse. We evaluated global cognition, behavior, and attention at age 5 y in the offspring of Mexican women who participated in a randomized controlled trial of prenatal DHA supplementation. A total of 1094 women were randomly assigned to receive 400 mg of either DHA or placebo/d from 18 to 22 wk of pregnancy until delivery. We assessed cognitive development and behavioral and executive functioning, including attention, in 797 offspring at age 5 y (82% of 973 live births) with the use of the McCarthy Scales of Children's Abilities (MSCA), the parental scale of the Behavioral Assessment System for Children, Second Edition (BASC-2), and the Conners' Kiddie Continuous Performance Test (K-CPT). We compared the groups on raw scores, T-scores, and standardized scores, as appropriate. We examined heterogeneity by the quality of the home environment, maternal intelligence, and socioeconomic status. There were no group differences for MSCA scores (P > 0.05), but the positive effect of the home environment at 12 mo on general cognitive abilities was attenuated in the DHA group compared with in the placebo group (P-interaction 0.05) for the other K-CPT scores or of the proportion who were clinically at risk of attention deficit hyperactivity disorders after Bonferroni correction for multiple comparisons. Prenatal exposure to DHA may contribute to improved sustained attention in preschool children. This trial was registered at clinicaltrials.gov as NCT00646360. © 2016 American Society for Nutrition.

Protectin DX, a double lipoxygenase product of DHA, inhibits both ROS production in human neutrophils and cyclooxygenase activities

Science.gov (United States)

Liu, Miao; Boussetta, Tarek; Makni-Maalej, Karama; Fay, Michèle; Driss, Fathi; El-Benna, Jamel; Lagarde, Michel; Guichardant, Michel

2014-01-01

Neutrophils play a major role in inflammation by releasing large amounts of reactive oxygen species (ROS) produced by NADPH oxidase (NOX) and myeloperoxidase (MPO). This ROS overproduction is mediated by phosphorylation of the NOX subunits with an uncontrolled manner. Therefore, targeting neutrophil subunits would represent a promising strategy to moderate NOX activity, lower ROS, and other inflammatory agents, such as cytokines and leukotrienes, produced by neutrophils. For this purpose, we investigated the effects of protectin DX (PDX) - a docosahexaenoic acid (DHA) di-hydroxylated product which inhibits blood platelet aggregation - on neutrophil activation in vitro. We found that PDX decreases ROS production, inhibits NOX activation and MPO release from neutrophils. We also confirm, that PDX is an anti-aggregatory and anti-inflammatory agent by inhibiting both cyclooxygenase-1 and -2 (COX-1 and COX-2, E.C. 1.14.99.1) as well as COX-2 in lipopolysaccharides (LPS)-treated human neutrophils. However, PDX has no effect on the 5-lipoxygenase pathway that produces the chemotactic agent leukotriene B4 (LTB4). Taken together, our results suggest that PDX could be a protective agent against neutrophil invasion in chronic inflammatory diseases. PMID:24254970

Lipid structure does not modify incorporation of EPA and DHA into blood lipids in healthy adults: a randomised-controlled trial.

Science.gov (United States)

West, Annette L; Burdge, Graham C; Calder, Philip C

2016-09-01

Dietary supplementation is an effective means to improve EPA and DHA status. However, it is unclear whether lipid structure affects EPA+DHA bioavailability. We determined the effect of consuming different EPA and DHA lipid structures on their concentrations in blood during the postprandial period and during dietary supplementation compared with unmodified fish oil TAG (uTAG). In a postprandial cross-over study, healthy men (n 9) consumed in random order test meals containing 1·1 g EPA+0·37 g DHA as either uTAG, re-esterified TAG, free fatty acids (FFA) or ethyl esters (EE). In a parallel design supplementation study, healthy men and women (n 10/sex per supplement) consumed one supplement type for 12 weeks. Fatty acid composition was determined by GC. EPA incorporation over 6 h into TAG or phosphatidylcholine (PC) did not differ between lipid structures. EPA enrichment in NEFA was lower from EE than from uTAG (P=0·01). Plasma TAG, PC or NEFA DHA incorporation did not differ between lipid structures. Lipid structure did not affect TAG or NEFA EPA incorporation and PC or NEFA DHA incorporation following dietary supplementation. Plasma TAG peak DHA incorporation was greater (P=0·02) and time to peak shorter (P=0·02) from FFA than from uTAG in men. In both studies, the order of EPA and DHA incorporation was PC>TAG>NEFA. In conclusion, EPA and DHA lipid structure may not be an important consideration in dietary interventions.

Assessment of creatine kinase and lactate dehydrogenase activities ...

African Journals Online (AJOL)

Ina bid to investigate the influence of menopausal on coronary heart disease, plasma creatine kinase (CK) and lactate dehydrogenase (LDH) enzymes were analysed on a prospective cohort of 100 women attending Irrua Specialist Teaching Hospital (ISTH), Irrua, Edo state-Nigeria. They were divided into two groups; ...

Low temperature electron beam irradiation effects on the lactate dehydrogenase activity

International Nuclear Information System (INIS)

Catana, D.; Hategan, Alina; Oproiu, C.; Popescu, Alina; Hategan, Dora; Morariu, V. V.

1998-01-01

The direct and indirect effects of 5 MeV electron beam irradiation in the range 0-400 Gy at 20 deg. C, -3 deg. C and -196 deg. C on the global enzymatic activity of lactate dehydrogenase (LDH) have been studied. Our results showed a monoexponential decrease in the enzymatic activity of irradiated LDH at all irradiation temperatures independently of direct or indirect action of radiation. The temperature gradient used to lower the temperature of the samples to -196 deg. C drastically influences the results. Our data suggest that freeze-thawing in two steps down to -196 deg. C make LDH insensitive to irradiation, while one step freeze-thawing procedure results in a gradual activity loss with increasing dose irradiation. This data can be interpreted in terms of different conformational changes during the particular freeze-thawing process. (authors)

3-cyanoindole-based inhibitors of inosine monophosphate dehydrogenase: synthesis and initial structure-activity relationships.

Science.gov (United States)

Dhar, T G Murali; Shen, Zhongqi; Gu, Henry H; Chen, Ping; Norris, Derek; Watterson, Scott H; Ballentine, Shelley K; Fleener, Catherine A; Rouleau, Katherine A; Barrish, Joel C; Townsend, Robert; Hollenbaugh, Diane L; Iwanowicz, Edwin J

2003-10-20

A series of novel small molecule inhibitors of inosine monophosphate dehydrogenase (IMPDH), based upon a 3-cyanoindole core, were explored. IMPDH catalyzes the rate determining step in guanine nucleotide biosynthesis and is a target for anticancer, immunosuppressive and antiviral therapy. The synthesis and the structure-activity relationships (SAR), derived from in vitro studies, for this new series of inhibitors is given.

Physiological covalent regulation of rat liver branched-chain alpha-ketoacid dehydrogenase

International Nuclear Information System (INIS)

Harris, R.A.; Powell, S.M.; Paxton, R.; Gillim, S.E.; Nagae, H.

1985-01-01

A radiochemical assay was developed for measuring branched-chain alpha-ketoacid dehydrogenase activity of Triton X-100 extracts of freeze-clamped rat liver. The proportion of active (dephosphorylated) enzyme was determined by measuring enzyme activities before and after activation of the complex with a broad-specificity phosphoprotein phosphatase. Hepatic branched-chain alpha-ketoacid dehydrogenase activity in normal male Wistar rats was 97% active but decreased to 33% active after 2 days on low-protein (8%) diet and to 13% active after 4 days on the same diet. Restricting protein intake of lean and obese female Zucker rats also caused inactivation of hepatic branched-chain alpha-ketoacid dehydrogenase complex. Essentially all of the enzyme was in the active state in rats maintained for 14 days on either 30 or 50% protein diets. This was also the case for rats maintained on a commercial chow diet (minimum 23% protein). However, maintaining rats on 20, 8, and 0% protein diets decreased the percentage of the active form of the enzyme to 58, 10, and 7% of the total, respectively. Fasting of chow-fed rats for 48 h had no effect on the activity state of hepatic branched-chain alpha-ketoacid dehydrogenase, i.e., 93% of the enzyme remained in the active state compared to 97% for chow-fed rats. However, hepatic enzyme of rats maintained on 8% protein diet was 10% active before starvation and 83% active after 2 days of starvation. Thus, dietary protein deficiency results in inactivation of hepatic branched-chain alpha-ketoacid dehydrogenase complex, presumably as a consequence of low hepatic levels of branched-chain alpha-ketoacids

Application of the Response Surface Methodology to Optimize the Fermentation Parameters for Enhanced Docosahexaenoic Acid (DHA) Production by Thraustochytrium sp. ATCC 26185.

Science.gov (United States)

Wu, Kang; Ding, Lijian; Zhu, Peng; Li, Shuang; He, Shan

2018-04-22

The aim of this study was to determine the cumulative effect of fermentation parameters and enhance the production of docosahexaenoic acid (DHA) by Thraustochytrium sp. ATCC 26185 using response surface methodology (RSM). Among the eight variables screened for effects of fermentation parameters on DHA production by Plackett-Burman design (PBD), the initial pH, inoculum volume, and fermentation volume were found to be most significant. The Box-Behnken design was applied to derive a statistical model for optimizing these three fermentation parameters for DHA production. The optimal parameters for maximum DHA production were initial pH: 6.89, inoculum volume: 4.16%, and fermentation volume: 140.47 mL, respectively. The maximum yield of DHA production was 1.68 g/L, which was in agreement with predicted values. An increase in DHA production was achieved by optimizing the initial pH, fermentation, and inoculum volume parameters. This optimization strategy led to a significant increase in the amount of DHA produced, from 1.16 g/L to 1.68 g/L. Thraustochytrium sp. ATCC 26185 is a promising resource for microbial DHA production due to the high-level yield of DHA that it produces, and the capacity for large-scale fermentation of this organism.

Marine Cryptophytes Are Great Sources of EPA and DHA

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Elina Peltomaa

2017-12-01

Full Text Available Microalgae have the ability to synthetize many compounds, some of which have been recognized as a source of functional ingredients for nutraceuticals with positive health effects. One well-known example is the long-chain polyunsaturated fatty acids (PUFAs, which are essential for human nutrition. Eicosapentaenoic acid (EPA and docosahexaenoic acid (DHA are the two most important long-chain omega-3 (ω-3 PUFAs involved in human physiology, and both industries are almost exclusively based on microalgae. In addition, algae produce phytosterols that reduce serum cholesterol. Here we determined the growth rates, biomass yields, PUFA and sterol content, and daily gain of eight strains of marine cryptophytes. The maximal growth rates of the cryptophytes varied between 0.34–0.70 divisions day−1, which is relatively good in relation to previously screened algal taxa. The studied cryptophytes were extremely rich in ω-3 PUFAs, especially in EPA and DHA (range 5.8–12.5 and 0.8–6.1 µg mg dry weight−1, respectively, but their sterol concentrations were low. Among the studied strains, Storeatula major was superior in PUFA production, and it also produces all PUFAs, i.e., α-linolenic acid (ALA, stearidonic acid (SDA, EPA, and DHA, which is rare in phytoplankton in general. We conclude that marine cryptophytes are a good alternative for the ecologically sustainable and profitable production of health-promoting lipids.

Prenatal DHA Status and Neurological Outcome in Children at Age 5.5 Years Are Positively Associated

NARCIS (Netherlands)

Victoria Escolano-Margarit, M.; Ramos, Rosa; Beyer, Jeannette; Csabi, Gyoergyi; Parrilla-Roure, Montserrat; Cruz, Francisco; Perez-Garcia, Miguel; Hadders-Algra, Mijna; Gil, Angel; Decsi, Tamas; Koletzko, Berthold V.; Campoy, Cristina

Beneficial effects of perinatal DHA supply on later neurological development have been reported. We assessed the effects of maternal DHA supplementation on the neurological development of their children. Healthy pregnant women from Spain, Germany, and Hungary were randomly assigned to a dietary

Dietary intake of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) in children - a workshop report

NARCIS (Netherlands)

Koletzko, B.; Uauy, R.; Palou, A.; Kok, F.J.; Hornstra, G.; Eilander, A.; Moretti, D.; Osendarp, S.J.M.; Zock, P.L.; Innis, S.

2010-01-01

There is controversy whether children should have a dietary supply of preformed long-chain polyunsaturated n-3 fatty acids EPA and DHA. The aims of the workshop were to review evidence for a possible benefit of a preformed EPA and/or DHA supply, of data required to set desirable intakes for children

Differential response to an algae supplement high in DHA mediated by maternal periconceptional diet: intergenerational effects of n-6 fatty acids.

Science.gov (United States)

Clayton, Edward H; Lamb, Tracy A; Refshauge, Gordon; Kerr, Matthew J; Bailes, Kristy L; Ponnampalam, Eric N; Friend, Michael A; Hopkins, David L

2014-08-01

Algae high in docosahexaenoic acid (DHA) may provide a source of long-chain omega-3 polyunsaturated fatty acids (LCn-3PUFA) for inclusion in the diet of lambs to improve the LCn-3PUFA status of meat. The effect of background LCn-3PUFA status on the metabolism of high DHA algae is, however, unknown. The aim of the current study was to determine whether the response to a high in DHA algae supplement fed to lambs for six weeks prior to slaughter was mediated by a maternal periconceptional diet. Forty Poll Dorset × Border Leicester × Merino weaner lambs were allocated to receive either a ration based on oat grain, lupin grain, and chopped lucerne (control) or the control ration with DHA-Gold™ algae included at 1.92 % DM (Algae) based on whether the dams of lambs had previously been fed a diet high in n-3 or n-6 around conception. LCn-3PUFA concentration was determined in plasma and red blood cells (RBC) prior to and following feeding. The concentrations of EPA and DHA in the plasma and RBC of lambs receiving the control ration were significantly (p DHA were also significantly (p DHA was, however, significantly (p DHA.

Characterization of human short chain dehydrogenase/reductase SDR16C family members related to retinol dehydrogenase 10.

Science.gov (United States)

Adams, Mark K; Lee, Seung-Ah; Belyaeva, Olga V; Wu, Lizhi; Kedishvili, Natalia Y

2017-10-01

All-trans-retinoic acid (RA) is a bioactive derivative of vitamin A that serves as an activating ligand for nuclear transcription factors, retinoic acid receptors. RA biosynthesis is initiated by the enzymes that oxidize retinol to retinaldehyde. It is well established that retinol dehydrogenase 10 (RDH10, SDR16C4), which belongs to the 16C family of the short chain dehydrogenase/reductase (SDR) superfamily of proteins, is the major enzyme responsible for the oxidation of retinol to retinaldehyde for RA biosynthesis during embryogenesis. However, several lines of evidence point towards the existence of additional retinol dehydrogenases that contribute to RA biosynthesis in vivo. In close proximity to RDH10 gene on human chromosome 8 are located two genes that are phylogenetically related to RDH10. The predicted protein products of these genes, retinol dehydrogenase epidermal 2 (RDHE2, SDR16C5) and retinol dehydrogenase epidermal 2-similar (RDHE2S, SDR16C6), share 59% and 56% sequence similarity with RDH10, respectively. Previously, we showed that the single ortholog of the human RDHE2 and RDHE2S in frogs, Xenopus laevis rdhe2, oxidizes retinol to retinaldehyde and is essential for frog embryonic development. In this study, we explored the potential of each of the two human proteins to contribute to RA biosynthesis. The results of this study demonstrate that human RDHE2 exhibits a relatively low but reproducible activity when expressed in either HepG2 or HEK293 cells. Expression of the native RDHE2 is downregulated in the presence of elevated levels of RA. On the other hand, the protein encoded by the human RDHE2S gene is unstable when expressed in HEK293 cells. RDHE2S protein produced in Sf9 cells is stable but has no detectable catalytic activity towards retinol. We conclude that the human RDHE2S does not contribute to RA biosynthesis, whereas the low-activity RA-sensitive human RDHE2 may have a role in adjusting the cellular levels of RA in accord with

Mfsd2a Is a Transporter for the Essential ω-3 Fatty Acid Docosahexaenoic Acid (DHA) in Eye and Is Important for Photoreceptor Cell Development.

Science.gov (United States)

Wong, Bernice H; Chan, Jia Pei; Cazenave-Gassiot, Amaury; Poh, Rebecca W; Foo, Juat Chin; Galam, Dwight L A; Ghosh, Sujoy; Nguyen, Long N; Barathi, Veluchamy A; Yeo, Sia W; Luu, Chi D; Wenk, Markus R; Silver, David L

2016-05-13

Eye photoreceptor membrane discs in outer rod segments are highly enriched in the visual pigment rhodopsin and the ω-3 fatty acid docosahexaenoic acid (DHA). The eye acquires DHA from blood, but transporters for DHA uptake across the blood-retinal barrier or retinal pigment epithelium have not been identified. Mfsd2a is a newly described sodium-dependent lysophosphatidylcholine (LPC) symporter expressed at the blood-brain barrier that transports LPCs containing DHA and other long-chain fatty acids. LPC transport via Mfsd2a has been shown to be necessary for human brain growth. Here we demonstrate that Mfsd2a is highly expressed in retinal pigment epithelium in embryonic eye, before the development of photoreceptors, and is the primary site of Mfsd2a expression in the eye. Eyes from whole body Mfsd2a-deficient (KO) mice, but not endothelium-specific Mfsd2a-deficient mice, were DHA-deficient and had significantly reduced LPC/DHA transport in vivo Fluorescein angiography indicated normal blood-retinal barrier function. Histological and electron microscopic analysis indicated that Mfsd2a KO mice exhibited a specific reduction in outer rod segment length, disorganized outer rod segment discs, and mislocalization of and reduction in rhodopsin early in postnatal development without loss of photoreceptors. Minor photoreceptor cell loss occurred in adult Mfsd2a KO mice, but electroretinography indicated visual function was normal. The developing eyes of Mfsd2a KO mice had activated microglia and up-regulation of lipogenic and cholesterogenic genes, likely adaptations to loss of LPC transport. These findings identify LPC transport via Mfsd2a as an important pathway for DHA uptake in eye and for development of photoreceptor membrane discs. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.

Radiation-induced alterations in succinate dehydrogenase activity in the muscle of pigeon

International Nuclear Information System (INIS)

Gadhia, P.K.; Shah, V.C.

1983-01-01

The histochemical changes in succinate dehydrogenase were investigated in pectoralis major muscle of pigeon exposed to sub-lethal dose (400 rad) of γ-irradiation. Biochemical study was also carried out after 200, 300 and 400 rad of irradiation. In the present study the overall decrease in enzyme activity could be due to the structural and/or functional damage to mitochondria after treatment of pigeon to different sub-lethal doses of γ-irradiation. The significance of these results has been discussed with special reference to oxidative metabolism. (author)

Comparison of the Incorporation of DHA in Circulatory and Neural Tissue When Provided as Triacylglycerol (TAG), Monoacylglycerol (MAG) or Phospholipids (PL) Provides New Insight into Fatty Acid Bioavailability.

Science.gov (United States)

Destaillats, Frédéric; Oliveira, Manuel; Bastic Schmid, Viktoria; Masserey-Elmelegy, Isabelle; Giuffrida, Francesca; Thakkar, Sagar K; Dupuis, Lénaïck; Gosoniu, Maria Laura; Cruz-Hernandez, Cristina

2018-05-15

Phospholipids (PL) or partial acylglycerols such as sn -1(3)-monoacylglycerol (MAG) are potent dietary carriers of long-chain polyunsaturated fatty acids (LC-PUFA) and have been reported to provide superior bioavailability when compared to conventional triacylglycerol (TAG). The main objective of the present study was to compare the incorporation of docosahexaenoic acid (DHA) in plasma, erythrocytes, retina and brain tissues in adult rats when provided as PL (PL-DHA) and MAG (MAG-DHA). Conventional dietary DHA oil containing TAG (TAG-DHA) as well as control chow diet were used to evaluate the potency of the two alternative DHA carriers over a 60-day feeding period. Fatty acid profiles were determined in erythrocytes and plasma lipids at time 0, 7, 14, 28, 35 and 49 days of the experimental period and in retina, cortex, hypothalamus, and hippocampus at 60 days. The assessment of the longitudinal evolution of DHA in erythrocyte and plasma lipids suggest that PL-DHA and MAG-DHA are efficient carriers of dietary DHA when compared to conventional DHA oil (TAG-DHA). Under these experimental conditions, both PL-DHA and MAG-DHA led to higher incorporations of DHA erythrocytes lipids compared to TAG-DHA group. After 60 days of supplementation, statistically significant increase in DHA level incorporated in neural tissues analyzed were observed in the DHA groups compared with the control. The mechanism explaining hypothetically the difference observed in circulatory lipids is discussed.

Supplementation of DHA but not DHA with arachidonic acid during pregnancy and lactation influences general movement quality in 12-week-old term infants

NARCIS (Netherlands)

van Goor, Saskia A.; Dijck-Brouwer, D. A. Janneke; Doornbos, Bennard; Erwich, Jan Jaap H. M.; Schaafsma, Anne; Muskiet, Frits A. J.; Hadders-Algra, Mijna

2010-01-01

DHA and arachidonic acid (AA) are important for neurodevelopment. A traditional neonatal neurological examination and the evaluation of general movement quality are sensitive techniques for assessing neurodevelopment in young infants. Mildly abnormal general movement,,; at 3 months have been

Progressive retinal degeneration and glial activation in the CLN6 (nclf mouse model of neuronal ceroid lipofuscinosis: a beneficial effect of DHA and curcumin supplementation.

Directory of Open Access Journals (Sweden)

Myriam Mirza

Full Text Available Neuronal ceroid lipofuscinosis (NCL is a group of neurodegenerative lysosomal storage disorders characterized by vision loss, mental and motor deficits, and spontaneous seizures. Neuropathological analyses of autopsy material from NCL patients and animal models revealed brain atrophy closely associated with glial activity. Earlier reports also noticed loss of retinal cells and reactive gliosis in some forms of NCL. To study this phenomenon in detail, we analyzed the ocular phenotype of CLN6 (nclf mice, an established mouse model for variant-late infantile NCL. Retinal morphometry, immunohistochemistry, optokinetic tracking, electroretinography, and mRNA expression were used to characterize retinal morphology and function as well as the responses of Müller cells and microglia. Our histological data showed a severe and progressive degeneration in the CLN6 (nclf retina co-inciding with reactive Müller glia. Furthermore, a prominent phenotypic transformation of ramified microglia to phagocytic, bloated, and mislocalized microglial cells was identified in CLN6 (nclf retinas. These events overlapped with a rapid loss of visual perception and retinal function. Based on the strong microglia reactivity we hypothesized that dietary supplementation with immuno-regulatory compounds, curcumin and docosahexaenoic acid (DHA, could ameliorate microgliosis and reduce retinal degeneration. Our analyses showed that treatment of three-week-old CLN6 (nclf mice with either 5% DHA or 0.6% curcumin for 30 weeks resulted in a reduced number of amoeboid reactive microglia and partially improved retinal function. DHA-treatment also improved the morphology of CLN6 (nclf retinas with a preserved thickness of the photoreceptor layer in most regions of the retina. Our results suggest that microglial reactivity closely accompanies disease progression in the CLN6 (nclf retina and both processes can be attenuated with dietary supplemented immuno-modulating compounds.

FADS genotype and diet are important determinants of DHA status: a cross-sectional study in Danish infants^1-3

DEFF Research Database (Denmark)

Harsløf, Laurine Bente Schram; Larsen, Lesli Hingstrup; Ritz, Christian

2013-01-01

Background: Infant docosahexaenoic acid (DHA) status is supported by the DHA content of breast milk and thus can decrease once complementary feeding begins. Furthermore, it is unclear to what extent endogenous DHA synthesis contributes to status. Objective: We investigated several determinants, i...

Ecoenzymatic stoichiometry and microbial processing of organic matter in northern bogs and fens reveals a common P-limitation between peatland types

Science.gov (United States)

Brian H. Hill; Colleen M. Elonen; Terri M. Jicha; Randall K. Kolka; LaRae L.P. Lehto; Stephen D. Sebestyen; Lindsey R. Seifert-Monson

2014-01-01

We compared carbon (C), nitrogen (N), and phosphorus (P) concentrations in atmospheric deposition, runoff, and soils with microbial respiration [dehydrogenase (DHA)] and ecoenzyme activity (EEA) in an ombrotrophic bog and a minerotrophic fen to investigate the environmental drivers of biogeochemical cycling in peatlands at the Marcell Experimental Forest in northern...

Differential effects of acute and chronic fructose administration on pyruvate dehydrogenase activity and lipogenesis

International Nuclear Information System (INIS)

Wilson, L.

1988-01-01

These studies were undertaken to distinguish between the acute and chronic effects of fructose administration. In vivo, liver lipogenesis, as measured by 3 H 2 O incorporation, was greater in rats fed 60% fructose than in their glucose fed controls. Both fructose feeding, and fructose feeding plus intraperitoneal fructose injection increased the activities of 6-phosphogluconate dehydrogenase and malic enzyme. Liver PDH activity was increased by fructose feeding, and was increased even more by fructose feeding and injection of fructose, but this was not associated with any changes in hepatic ATP concentrations

Sex-specific effects of docosahexaenoic acid (DHA) on the microbiome and behavior of socially-isolated mice.

Science.gov (United States)

Davis, Daniel J; Hecht, Patrick M; Jasarevic, Eldin; Beversdorf, David Q; Will, Matthew J; Fritsche, Kevin; Gillespie, Catherine H

2017-01-01

Dietary supplementation with the long-chain omega-3 polyunsaturated fatty acid docosahexaenoic acid (DHA) has been shown to have a beneficial effect on reducing the symptoms associated with several neuropsychiatric conditions including anxiety and depression. However, the mechanisms underlying this effect remain largely unknown. Increasing evidence suggests that the vast repertoire of commensal bacteria within the gut plays a critical role in regulating various biological processes in the brain and may contribute to neuropsychiatric disease risk. The present study determined the contribution of DHA on anxiety and depressive-like behaviors through modulation of the gut microbiota in a paradigm of social isolation. Adult male and female mice were subjected to social isolation for 28days and then placed either on a control diet or a diet supplemented with 0.1% or 1.0% DHA. Fecal pellets were collected both 24h and 7days following the introduction of the new diets. Behavioral testing revealed that male mice fed a DHA diet, regardless of dose, exhibited reduced anxiety and depressive-like behaviors compared to control fed mice while no differences were observed in female mice. As the microbiota-brain-axis has been recently implicated in behavior, composition of microbial communities were analyzed to examine if these sex-specific effects of DHA may be associated with changes in the gut microbiota (GM). Clear sex differences were observed with males and females showing distinct microbial compositions prior to DHA supplementation. The introduction of DHA into the diet also induced sex-specific interactions on the GM with the fatty acid producing a significant effect on the microbial profiles in males but not in females. Interestingly, levels of Allobaculum and Ruminococcus were found to significantly correlate with the behavioral changes observed in the male mice. Predictive metagenome analysis using PICRUSt was performed on the fecal samples collected from males and

DHA and EPA Content and Fatty Acid Profile of 39 Food Fishes from India

Directory of Open Access Journals (Sweden)

Bimal Prasanna Mohanty

2016-01-01

Full Text Available Docosahexaenoic acid (DHA is the principal constituent of a variety of cells especially the brain neurons and retinal cells and plays important role in fetal brain development, development of motor skills, and visual acuity in infants, lipid metabolism, and cognitive support and along with eicosapentaenoic acid (EPA it plays important role in preventing atherosclerosis, dementia, rheumatoid arthritis, Alzheimer’s disease, and so forth. Being an essential nutrient, it is to be obtained through diet and therefore searching for affordable sources of these ω-3 polyunsaturated fatty acids (PUFA is important for consumer guidance and dietary counseling. Fish is an important source of PUFA and has unique advantage that there are many food fish species available and consumers have a wide choice owing to availability and affordability. The Indian subcontinent harbors a rich fish biodiversity which markedly varies in their nutrient composition. Here we report the DHA and EPA content and fatty acid profile of 39 important food fishes (including finfishes, shellfishes, and edible molluscs from both marine water and freshwater from India. The study showed that fishes Tenualosa ilisha, Sardinella longiceps, Nemipterus japonicus, and Anabas testudineus are rich sources of DHA and EPA. Promotion of these species as DHA rich species would enhance their utility in public health nutrition.

Effects of DHA Supplementation on Vascular Function, Telomerase Activity in PBMC, Expression of Inflammatory Cytokines, and PPARγ-LXRα-ABCA1 Pathway in Patients With Type 2 Diabetes Mellitus: Study Protocol for Randomized Controlled Clinical Trial

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Omid Toupchian

2016-07-01

Full Text Available Docosahexaenoic acid (DHA, as an omega-3 fatty acid, in a natural ligand of peroxisome proliferator-activated receptors (PPARs. Regarding the combinative effects of Nutrigenomics and Nutrigenetics and due to the lack of in vivo studies conducted using natural ligands of PPARs, we aimed to evaluate the effects of DHA supplementation on vascular function, telomerase activity, and PPARγ-LXRα-ABCA1 pathway, in patients with type 2 diabetes mellitus (T2DM, based on the Pro12Ala polymorphism in PPARγ encoding gene. 72 T2DM patients (36 dominant and 36 recessive allele carriers, aged 30-70, with body mass index of 18.5 to 35 kg/m2, will be participated in this double blind randomized controlled trial. In each group, stratification will be performed based on sex and age and participants will be randomly assigned to receive 2.4 g/day DHA or placebo (paraffin for 8 weeks. PPARγ genotyping will be carried out using PCR-RFLP method; Telomerase activity will be estimated by PCR-ELISA TRAP assay; mRNA expression levels of target genes will be assessed using real time PCR. Serum levels of ADMA, sCD163 and adiponectin, will be measured using ELISA commercial kits. The present study is designed in order to help T2DM patients to modify their health conditions based on their genetic backgrounds, and to recommend the proper food ingredients as the natural agonists for PPARs in order to prevent and treat metabolic abnormalities of the disease.

Determination of glutamate dehydrogenase activity and its kinetics in mouse tissues using metabolic mapping (quantitative enzyme histochemistry)

NARCIS (Netherlands)

Botman, Dennis; Tigchelaar, Wikky; van Noorden, Cornelis J. F.

2014-01-01

Glutamate dehydrogenase (GDH) catalyses the reversible conversion of glutamate into α-ketoglutarate with the concomitant reduction of NAD(P)(+) to NAD(P)H or vice versa. GDH activity is subject to complex allosteric regulation including substrate inhibition. To determine GDH kinetics in situ, we

Effect of Docosahexaenoic Acid (DHA) Supplementation on Inflammatory Cytokine Levels in Infants at High Genetic Risk for Type 1 Diabetes

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Chase, H. Peter; Boulware, David; Rodriguez, Henry; Donaldson, David; Chritton, Sonia; Rafkin-Mervis, Lisa; Krischer, Jeffrey; Skyler, Jay S.; Clare-Salzler, Michael

2014-01-01

OBJECTIVE Type 1 diabetes (T1D) results from the inflammatory destruction of pancreatic β-cells. In the present study, we investigated the effect of docosahexaenoic acid (DHA) supplementation on stimulated inflammatory cytokine production in white blood cells (WBC) from infants with a high genetic risk for T1D. RESEARCH DESIGN AND METHODS This was a multicenter, two-arm, randomized, double blind pilot trial of DHA supplementation, beginning either in the last trimester of pregnancy (41 infants) or in the first five months after birth (57 infants). Levels of DHA in infant and maternal red blood cell (RBC) membranes and in breast milk were analyzed by gas chromatography/mass spectrometry. Inflammatory cytokines were assayed from whole blood culture supernatants using the Luminex Multiplex assay after stimulation with high dose lipopolysaccharide (LPS), 1μg/mL. RESULTS The levels of RBC DHA were increased by 61–100% in treated compared to control infants at ages 6 to 36 months. There were no statistically significant reductions in production of the inflammatory cytokines, IL-1β, TNFα or IL-12p40 at any of the 6 time points measured. The inflammatory marker, hsCRP, was significantly lower in breast-fed DHA-treated infants compared to all formula-fed infants at age 12 months. Three infants (two received DHA) were removed from the study as a result of developing ≥ two persistently positive biochemical islet autoantibodies. CONCLUSIONS This pilot trial showed that supplementation of infant diets with DHA is safe and fulfilled the pre-study goal of increasing infant RBC DHA levels by at least 20%. Inflammatory cytokine production was not consistently reduced. PMID:25039804

Glyceraldehyde-3-phosphate dehydrogenase from Chironomidae showed differential activity towards metals.

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Chong, Isaac K W; Ho, Wing S

2013-09-01

Glyceraldehyde-3-phosphate dehydrogenase (GAPDH) is known to interact with different biomolecules and was implicated in many novel cellular activities including programmed cell death, nuclear RNA transport unrelated to the commonly known carbohydrate metabolism. We reported here the purification of GAPDH from Chironomidae larvae (Insecta, Diptera) that showed different biologic activity towards heavy metals. It was inhibited by copper, cobalt nickel, iron and lead but was activated by zinc. The GAPDH was purified by ammonium sulphate fractionation and Chelating Sepharose CL-6B chromatography followed by Blue Sepharose CL-6B chromatography. The 150-kDa tetrameric GAPDH showed optimal activity at pH 8.5 and 37°C. The multiple alignment of sequence of the Chironomidae GAPDH with other known species showed 78 - 88% identity to the conserved regions of the GADPH. Bioinformatic analysis unveils substantial N-terminal sequence similarity of GAPDH of Chironomidae larvae to mammalian GADPHs. However, the GADPH of Chironomidae larvae showed different biologic activities and cytotoxicity towards heavy metals. The GAPDH enzyme would undergo adaptive molecular changes through binding at the active site leading to higher tolerance to heavy metals.

Enhancing physicochemical properties of emulsions by heteroaggregation of oppositely charged lactoferrin coated lutein droplets and whey protein isolate coated DHA droplets.

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Li, Xin; Wang, Xu; Xu, Duoxia; Cao, Yanping; Wang, Shaojia; Wang, Bei; Sun, Baoguo; Yuan, Fang; Gao, Yanxiang

2018-01-15

The formation and physicochemical stability of mixed functional components (lutein & DHA) emulsions through heteroaggregation were studied. It was formed by controlled heteroaggregation of oppositely charged lutein and DHA droplets coated by cationic lactoferrin (LF) and anionic whey protein isolate (WPI), respectively. Heteroaggregation was induced by mixing the oppositely charged LF-lutein and WPI-DHA emulsions together at pH 6.0. Droplet size, zeta-potential, transmission-physical stability, microrheological behavior and microstructure of the heteroaggregates formed were measured as a function of LF-lutein to WPI-DHA droplet ratio. Lutein degradation and DHA oxidation by measurement of lipid hydroperoxides and thiobarbituric acid reactive substances were determined. Upon mixing the two types of bioactive compounds droplets together, it was found that the largest aggregates and highest physical stability occurred at a droplet ratio of 40% LF-lutein droplets to 60% WPI-DHA droplets. Heteroaggregates formation altered the microrheological properties of the mixed emulsions mainly by the special network structure of the droplets. When LF-coated lutein droplets ratios were more than 30% and less than 60%, the mixed emulsions exhibited distinct decreases in the Mean Square Displacement, which indicated that their limited scope of Brownian motion and stable structure. Mixed emulsions with LF-lutein/WPI-DHA droplets ratio of 4:6 exhibited Macroscopic Viscosity Index with 13 times and Elasticity Index with 3 times of magnitudes higher than the individual emulsions from which they were prepared. Compared with the WPI-DHA emulsion or LF-lutein emulsion, the oxidative stability of the heteroaggregate of LF-lutein/WPI-DHA emulsions was improved. Heteroaggregates formed by oppositely charged bioactive compounds droplets may be useful for creating specific food structures that lead to desirable physicochemical properties, such as microrheological property, physical and chemical

Docosahexaenoic (DHA modulates phospholipid-hydroperoxide glutathione peroxidase (Gpx4 gene expression to ensure self-protection from oxidative damage in hippocampal cells

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Veronica eCasañas-Sanchez

2015-07-01

Full Text Available Docosahexaenoic acid (DHA, 22:6n-3 is a unique polyunsaturated fatty acid particularly abundant in nerve cell membrane phospholipids. DHA is a pleiotropic molecule that, not only modulates the physicochemical properties and architecture of neuronal plasma membrane, but it is also involved in multiple facets of neuronal biology, from regulation of synaptic function to neuroprotection and modulation of gene expression. As a highly unsaturated fatty acid due to the presence of six double bonds, DHA is susceptible for oxidation, especially in the highly pro-oxidant environment of brain parenchyma. We have recently reported the ability of DHA to regulate the transcriptional program controlling neuronal antioxidant defenses in a hippocampal cell line, especially the glutathione/glutaredoxin system. Within this antioxidant system, DHA was particularly efficient in triggering the upregulation of Gpx4 gene, which encodes for the nuclear, cytosolic and mitochondrial isoforms of phospholipid-hydroperoxide glutathione peroxidase (PH-GPx/GPx4, the main enzyme protecting cell membranes against lipid peroxidation and capable to reduce oxidized phospholipids in situ. We show here that this novel property of DHA is also significant in the hippocampus of wild-type mice and APP/PS1 transgenic mice, a familial model of Alzheimer’s disease. By doing this, DHA stimulates a mechanism to self-protect from oxidative damage even in the neuronal scenario of high aerobic metabolism and in the presence of elevated levels of transition metals, which inevitably favor the generation of reactive oxygen species. Noticeably, DHA also upregulated a novel Gpx4 splicing variant, harboring part of the first intronic region, which according to the ‘sentinel RNA hypothesis’ would expand the ability of Gpx4 (and DHA to provide neuronal antioxidant defense independently of conventional nuclear splicing in cellular compartments, like dendritic zones, located away from nuclear

Succinate Dehydrogenase Activity Assay in situ with Blue Tetrazolium Salt in Crabtree-Positive Saccharomyces cerevisiae Strain

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Joanna Berlowska

2008-01-01

Full Text Available A spectrophotometric method for determining succinate dehydrogenase (SDH activity assay in azide-sensitive yeast Saccharomyces cerevisiae has been developed. The permeabilization of yeast cells by 0.05 % digitonin permitted to study yeast enzymatic activity in situ. The reduction of blue tetrazolium salt (BT to blue tetrazolium formazan (BTf was conducted in the presence of phenazine methosulphate (PMS as an exogenous electron carrier, and sodium azide (SA as an inhibitor of cytochrome oxidase (Cyt pathway. Various factors such as type of substrate, BT concentration, cell number, temperature and time of incubation, and different Cyt pathway blockers were optimized. In earlier studies, dimethyl sulfoxide (DMSO had been selected as the best solvent for extraction of BTf from yeast cells. The linear correlation between permeabilized yeast cell density and amount of formed formazan was evidenced in the range from 9·10^7 to 5·10^8 cells per sample solution. Below the yeast cell concentration of 10^7 the absorbance values were too low to detect formazans with good precision. This standarized procedure allows the estimation of SDH activity in whole cells, depending on vitality level of yeast populations. Significant increases of succinate dehydrogenase activities were observed in sequential passages as the result of the increase of activity of the strain and adaptation to cultivation conditions.

DHA-rich n-3 fatty acid supplementation decreases DNA methylation in blood leukocytes: the OmegAD study.

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Karimi, Mohsen; Vedin, Inger; Freund Levi, Yvonne; Basun, Hans; Faxén Irving, Gerd; Eriksdotter, Maria; Wahlund, Lars-Olof; Schultzberg, Marianne; Hjorth, Erik; Cederholm, Tommy; Palmblad, Jan

2017-10-01

Background: Dietary fish oils, rich in long-chain n-3 (ω-3) fatty acids (FAs) [e.g., docosahexaenoic acid (DHA, 22:6n-3) and eicosapentaenoic acid (EPA, 20:5n-3)], modulate inflammatory reactions through various mechanisms, including gene expression, which is measured as messenger RNA concentration. However, the effects of long-term treatment of humans with DHA and EPA on various epigenetic factors-such as DNA methylation, which controls messenger RNA generation-are poorly described. Objective: We wanted to determine the effects of 6 mo of dietary supplementation with an n-3 FA preparation rich in DHA on global DNA methylation of peripheral blood leukocytes (PBLs) and the relation to plasma EPA and DHA concentrations in Alzheimer disease (AD) patients. Design: In the present study, DNA methylation in four 5'-cytosine-phosphate-guanine-3' (CpG) sites of long interspersed nuclear element-1 repetitive sequences was assessed in a group of 63 patients (30 given the n-3 FA preparation and 33 given placebo) as an estimation of the global DNA methylation in blood cells. Patients originated from the randomized, double-blind, placebo-controlled OmegAD study, in which 174 AD patients received either 1.7 g DHA and 0.6 g EPA (the n-3 FA group) or placebo daily for 6 mo. Results: At 6 mo, the n-3 FA group displayed marked increases in DHA and EPA plasma concentrations (2.6- and 3.5-fold), as well as decreased methylation in 2 out of 4 CpG sites ( P DHA concentration, and were not related to apolipoprotein E-4 allele frequency. Conclusion: Supplementation with n-3 FA for 6 mo was associated with global DNA hypomethylation in PBLs. Our data may be of importance in measuring various effects of marine oils, including gene expression, in patients with AD and in other patients taking n-3 FA supplements. This trial was registered at clinicaltrials.gov as NCT00211159. © 2017 American Society for Nutrition.

The Effect of Omega-3 Fatty Acids, EPA, and/or DHA on Male Infertility: A Systematic Review and Meta-analysis.

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Hosseini, Banafshe; Nourmohamadi, Mahdieh; Hajipour, Shima; Taghizadeh, Mohsen; Asemi, Zatollah; Keshavarz, Seyed Ali; Jafarnejad, Sadegh

2018-02-16

The objective was to evaluate the effect of docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) on sperm parameters including total sperm concentration, sperm motility, sperm DHA, and seminal plasma DHA concentration in infertile men. The literature search was conducted in PubMed, Google Scholar, and Scopus from January 1, 1990 to December 20, 2017. The systematic review and meta-analysis were based on randomized controlled trials in infertile men with DHA or EPA treatments, either alone or in combination with other micronutrients. Three studies met the inclusion criteria: 147 patients in the intervention group and 143 patients in the control group. The analysis showed that omega-3 treatments significantly increased the sperm motility (RR 5.82, 95% CI [2.91, 8.72], p DHA concentration (RR 1.61, 95% CI [0.15, 3.07], p =. 03, I 2 = 98%). Compared with the controls, the interventions did not affect the sperm concentration (RR 0.31, 95% CI [-8.13, 8.76], p =. 94, I 2 = 95%) or sperm DHA (RR 0.50, 95% CI [-4.17, 5.16], p =. 83, I 2 = 99%). The observed heterogeneity may be due to administration period and dosage of omega-3 fatty acids across the studies. Funnel plot shows no evidence of publication bias. This meta-analysis indicates that supplementing infertile men with omega-3 fatty acids resulted in a significant improvement in sperm motility and concentration of DHA in seminal plasma.

Structural and kinetic basis for substrate selectivity in Populus tremuloides sinapyl alcohol dehydrogenase.

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Bomati, Erin K; Noel, Joseph P

2005-05-01

We describe the three-dimensional structure of sinapyl alcohol dehydrogenase (SAD) from Populus tremuloides (aspen), a member of the NADP(H)-dependent dehydrogenase family that catalyzes the last reductive step in the formation of monolignols. The active site topology revealed by the crystal structure substantiates kinetic results indicating that SAD maintains highest specificity for the substrate sinapaldehyde. We also report substantial substrate inhibition kinetics for the SAD-catalyzed reduction of hydroxycinnamaldehydes. Although SAD and classical cinnamyl alcohol dehydrogenases (CADs) catalyze the same reaction and share some sequence identity, the active site topology of SAD is strikingly different from that predicted for classical CADs. Kinetic analyses of wild-type SAD and several active site mutants demonstrate the complexity of defining determinants of substrate specificity in these enzymes. These results, along with a phylogenetic analysis, support the inclusion of SAD in a plant alcohol dehydrogenase subfamily that includes cinnamaldehyde and benzaldehyde dehydrogenases. We used the SAD three-dimensional structure to model several of these SAD-like enzymes, and although their active site topologies largely mirror that of SAD, we describe a correlation between substrate specificity and amino acid substitution patterns in their active sites. The SAD structure thus provides a framework for understanding substrate specificity in this family of enzymes and for engineering new enzyme specificities.

DHA-Mediated Regulation of Lung Cancer Cell Migration Is Not Directly Associated with Gelsolin or Vimentin Expression

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Ali, Mehboob; Heyob, Kathryn; Rogers, Lynette K.

2016-01-01

AIMS Deaths associated with cancer metastasis have steadily increased making the need for newer, anti-metastatic therapeutics imparative. Gelsolin and vimentin, actin binding proteins expressed in metastatic tumors, participate in actin remodelling and regulate cell migration. Docosahexaenoic acid (DHA) limits cancer cell proliferation and adhesion but the mechanisms involved in reducing metastatic phenotypes are unknown. We aimed to investigate the effects of DHA on gelsolin and vimentin expression, and ultimately cell migration and proliferation, in this context. MAIN METHODS Non-invasive lung epithelial cells (MLE12) and invasive lung cancer cells (A549) were treated with DHA (30 μmol/ml) or/and 8 bromo-cyclic adenosine monophosphate (8 Br-cAMP) (300 μmol/ml) for 6 or 24 h either before (pre-treatment) or after (post-treatment) plating in transwells. Migration was assessed by the number of cells that progressed through the transwell. Gelsolin and vimentin expression were measured by western blot and confocal microscopy in cells, and by immunohistochemistry in human lung cancer biospy samples. KEY FINDINGS A significant decrease in cell migration was detected for A549 cells treated with DHA verses control but this same decrease was not seen in MLE12 cells. DHA and 8 Br-cAMP altered gelsolin and vimentin expression but no clear pattern of change was observed. Immunoflorescence staining indicated slightly higher vimentin expression in human lung tissue that was malignant compared to control. SIGNIFICANCE Collectively, our data indicate that DHA inhibits cancer cell migration and further suggests that vimentin and gelsolin may play secondary roles in cancer cell migration and proliferation, but are not the primary regulators. PMID:27157519

Food Sources of EPA and DHA in the Diets of American Children, NHANES 2003-2010

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Kranz, Sibylle; Huss, Lyndsey R.; Dobbs-Oates, Jennifer

2015-01-01

Objective Dietary eicosapentaenoicacid (EPA) and docosahexaenoic acid (DHA) are found in the highest concentrations in fish and seafood. As important nutrients for brain and eye development and function, their consumption levels are of public health interest, especially in children. This study was conducted toexamine children’sreported consumption of fish and shellfish as well as EPA and DHA intake.Methods Secondary analysis of dietary intake (24-hour recall) and Food Frequency Questionnaire ...

Effects of Eicosapentaenoic Acid (EPA) and Docosahexaenoic Acid (DHA) on Fetal Pulmonary Circulation: An Experimental Study in Fetal Lambs.

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Sharma, Dyuti; Aubry, Estelle; Ouk, Thavarak; Houeijeh, Ali; Houfflin-Debarge, Véronique; Besson, Rémi; Deruelle, Philippe; Storme, Laurent

2017-07-16

Background: Persistent pulmonary hypertension of the newborn (PPHN) causes significant morbidity and mortality in neonates. n -3 Poly-unsaturated fatty acids have vasodilatory properties in the perinatal lung. We studied the circulatory effects of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) in fetal sheep and in fetal pulmonary arterial rings. Methods: At 128 days of gestation, catheters were placed surgically in fetal systemic and pulmonary circulation, and a Doppler probe around the left pulmonary artery (LPA). Pulmonary arterial pressure and LPA flow were measured while infusing EPA or DHA for 120 min to the fetus, to compute pulmonary vascular resistance (PVR). The dose effects of EPA or DHA were studied in vascular rings pre-constricted with serotonin. Rings treated with EPA were separated into three groups: E+ (intact endothelium), E- (endothelium stripped) and LNA E+ (pretreatment of E+ rings with l-nitro-arginine). Results: EPA, but not DHA, induced a significant and prolonged 25% drop in PVR ( n = 8, p DHA resulted in only a mild relaxation at the highest concentration of DHA (300 µM) compared to E+. Conclusions: EPA induces a sustained pulmonary vasodilatation in fetal lambs. This effect is endothelium- and dose-dependent and involves nitric oxide (NO) production. We speculate that EPA supplementation may improve pulmonary circulation in clinical conditions with PPHN.

Structural Insights into l-Tryptophan Dehydrogenase from a Photoautotrophic Cyanobacterium, Nostoc punctiforme.

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Wakamatsu, Taisuke; Sakuraba, Haruhiko; Kitamura, Megumi; Hakumai, Yuichi; Fukui, Kenji; Ohnishi, Kouhei; Ashiuchi, Makoto; Ohshima, Toshihisa

2017-01-15

l-Tryptophan dehydrogenase from Nostoc punctiforme NIES-2108 (NpTrpDH), despite exhibiting high amino acid sequence identity (>30%)/homology (>50%) with NAD(P) + -dependent l-Glu/l-Leu/l-Phe/l-Val dehydrogenases, exclusively catalyzes reversible oxidative deamination of l-Trp to 3-indolepyruvate in the presence of NAD + Here, we determined the crystal structure of the apo form of NpTrpDH. The structure of the NpTrpDH monomer, which exhibited high similarity to that of l-Glu/l-Leu/l-Phe dehydrogenases, consisted of a substrate-binding domain (domain I, residues 3 to 133 and 328 to 343) and an NAD + /NADH-binding domain (domain II, residues 142 to 327) separated by a deep cleft. The apo-NpTrpDH existed in an open conformation, where domains I and II were apart from each other. The subunits dimerized themselves mainly through interactions between amino acid residues around the β-1 strand of each subunit, as was observed in the case of l-Phe dehydrogenase. The binding site for the substrate l-Trp was predicted by a molecular docking simulation and validated by site-directed mutagenesis. Several hydrophobic residues, which were located in the active site of NpTrpDH and possibly interacted with the side chain of the substrate l-Trp, were arranged similarly to that found in l-Leu/l-Phe dehydrogenases but fairly different from that of an l-Glu dehydrogenase. Our crystal structure revealed that Met-40, Ala-69, Ile-74, Ile-110, Leu-288, Ile-289, and Tyr-292 formed a hydrophobic cluster around the active site. The results of the site-directed mutagenesis experiments suggested that the hydrophobic cluster plays critical roles in protein folding, l-Trp recognition, and catalysis. Our results provide critical information for further characterization and engineering of this enzyme. In this study, we determined the three-dimensional structure of l-Trp dehydrogenase, analyzed its various site-directed substitution mutants at residues located in the active site, and obtained the

A Case of Hyperammonemia Associated with High Dihydropyrimidine Dehydrogenase Activity

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Keiki Nagaharu

2016-01-01

Full Text Available Over the past decades, 5-Fluorouracil (5-FU has been widely used to treat several types of carcinoma, including esophageal squamous cell carcinoma. In addition to its common side effects, including diarrhea, mucositis, neutropenia, and anemia, 5-FU treatment has also been reported to cause hyperammonemia. However, the exact mechanism responsible for 5-FU-induced hyperammonemia remains unknown. We encountered an esophageal carcinoma patient who developed hyperammonemia when receiving 5-FU-containing chemotherapy but did not exhibit any of the other common adverse effects of 5-FU treatment. At the onset of hyperammonemia, laboratory tests revealed high dihydropyrimidine dehydrogenase (DPD activity and rapid 5-FU clearance. Our findings suggested that 5-FU hypermetabolism may be one of the key mechanisms responsible for hyperammonemia during 5-FU treatment.

Molecular Basis for Converting (2S-Methylsuccinyl-CoA Dehydrogenase into an Oxidase

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Simon Burgener

2017-12-01

Full Text Available Although flavoenzymes have been studied in detail, the molecular basis of their dioxygen reactivity is only partially understood. The members of the flavin adenosine dinucleotide (FAD-dependent acyl-CoA dehydrogenase and acyl-CoA oxidase families catalyze similar reactions and share common structural features. However, both enzyme families feature opposing reaction specificities in respect to dioxygen. Dehydrogenases react with electron transfer flavoproteins as terminal electron acceptors and do not show a considerable reactivity with dioxygen, whereas dioxygen serves as a bona fide substrate for oxidases. We recently engineered (2S-methylsuccinyl-CoA dehydrogenase towards oxidase activity by rational mutagenesis. Here we characterized the (2S-methylsuccinyl-CoA dehydrogenase wild-type, as well as the engineered (2S-methylsuccinyl-CoA oxidase, in detail. Using stopped-flow UV-spectroscopy and liquid chromatography-mass spectrometry (LC-MS based assays, we explain the molecular base for dioxygen reactivity in the engineered oxidase and show that the increased oxidase function of the engineered enzyme comes at a decreased dehydrogenase activity. Our findings add to the common notion that an increased activity for a specific substrate is achieved at the expense of reaction promiscuity and provide guidelines for rational engineering efforts of acyl-CoA dehydrogenases and oxidases.

Synthesis and antifungal activity of nicotinamide derivatives as succinate dehydrogenase inhibitors.

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Ye, Yong-Hao; Ma, Liang; Dai, Zhi-Cheng; Xiao, Yu; Zhang, Ying-Ying; Li, Dong-Dong; Wang, Jian-Xin; Zhu, Hai-Liang

2014-05-07

Thirty-eight nicotinamide derivatives were designed and synthesized as potential succinate dehydrogenase inhibitors (SDHI) and precisely characterized by (1)H NMR, ESI-MS, and elemental analysis. The compounds were evaluated against two phytopathogenic fungi, Rhizoctonia solani and Sclerotinia sclerotiorum, by mycelia growth inhibition assay in vitro. Most of the compounds displayed moderate activity, in which, 3a-17 exhibited the most potent antifungal activity against R. solani and S. sclerotiorum with IC50 values of 15.8 and 20.3 μM, respectively, comparable to those of the commonly used fungicides boscalid and carbendazim. The structure-activity relationship (SAR) of nicotinamide derivatives demonstrated that the meta-position of aniline was a key position contributing to the antifungal activity. Inhibition activities against two fungal SDHs were tested and achieved the same tendency with the data acquired from in vitro antifungal assay. Significantly, 3a-17 was demonstrated to successfully suppress disease development in S. sclerotiorum infected cole in vivo. In the molecular docking simulation, sulfur and chlorine of 3a-17 were bound with PHE291 and PRO150 of the SDH homology model, respectively, which could explain the probable mechanism of action between the inhibitory and target protein.

The Role of Docosahexaenoic Acid (DHA) in the Control of Obesity and Metabolic Derangements in Breast Cancer.

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Molfino, Alessio; Amabile, Maria Ida; Monti, Massimo; Arcieri, Stefano; Rossi Fanelli, Filippo; Muscaritoli, Maurizio

2016-04-05

Obesity represents a major under-recognized preventable risk factor for cancer development and recurrence, including breast cancer (BC). Healthy diet and correct lifestyle play crucial role for the treatment of obesity and for the prevention of BC. Obesity is significantly prevalent in western countries and it contributes to almost 50% of BC in older women. Mechanisms underlying obesity, such as inflammation and insulin resistance, are also involved in BC development. Fatty acids are among the most extensively studied dietary factors, whose changes appear to be closely related with BC risk. Alterations of specific ω-3 polyunsaturated fatty acids (PUFAs), particularly low basal docosahexaenoic acid (DHA) levels, appear to be important in increasing cancer risk and its relapse, influencing its progression and prognosis and affecting the response to treatments. On the other hand, DHA supplementation increases the response to anticancer therapies and reduces the undesired side effects of anticancer therapies. Experimental and clinical evidence shows that higher fish consumption or intake of DHA reduces BC cell growth and its relapse risk. Controversy exists on the potential anticancer effects of marine ω-3 PUFAs and especially DHA, and larger clinical trials appear mandatory to clarify these aspects. The present review article is aimed at exploring the capacity of DHA in controlling obesity-related inflammation and in reducing insulin resistance in BC development, progression, and response to therapies.

Docosahexaenoic acid (DHA, an essential fatty acid for the proper functioning of neuronal cells: their role in mood disorders

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2009-06-01

Full Text Available The brain and the nervous system are tissues with high contents of two polyunsaturated fatty acids: arachidonic acid (20:4, omega-6, AA and docosahexaenoic acid (22:6, omega-3, DHA. Despite their abundance in these tissues, AA and DHA cannot be re-synthesized in mammals. However, the concentration of these fatty acids can be modulated by dietary intake. AA and DHA must be provided by the diet as such (preformed or through the respective omega-6 and omega-3 precursors from vegetable origin. Linoleic acid, the precursor of AA is very abundant in the western diet and therefore the formation of AA from linoleic acid is not restrictive. On the other hand, alpha linolenic acid, the precursor of DHA is less available in our diet and preformed DHA is highly restrictive in some populations. During the last period of gestation and during the early post natal period, neurodevelopment occurs exceptionally quickly, and significant amounts of omega-6 and omega-3 polyunsaturated fatty acids, especially DHA, are critical to allow neurite outgrowth and the proper brain and retina development and function. In this review various functions of DHA in the nervous system, its metabolism into phospholipids, and its involvement in different neurological and mood disorders, such as Alzheimer’s disease, depression, and others are revised.

El cerebro y el sistema nervioso son tejidos con un alto contenido de dos ácidos grasos poliinsaturados: el ácido araquidónico (20:4, omega-6, AA y el ácido docosahexaenoico (22:6, omega-3, DHA. A pesar de la abundancia de estos ácidos grasos en dichos tejidos los mamíferos no los pueden sintetizar de novo. Sin embargo, la concentración de estos ácidos grasos puede ser modificada por la dieta. El AA y el DHA pueden ser aportados por la dieta como tales (preformados o a partir de los respectivos precursores de origen vegetal. El ácido linoleico, precursor del AA es muy abundante en la dieta occidental, por lo cual la

Effects of clofibric acid on the activity and activity state of the hepatic branched-chain 2-oxo acid dehydrogenase complex.

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Zhao, Y; Jaskiewicz, J; Harris, R A

1992-01-01

Feeding clofibric acid to rats caused little or no change in total activity of the liver branched-chain 2-oxo acid dehydrogenase complex (BCODC). No change in mass of liver BCODC was detected by immunoblot analysis in response to dietary clofibric acid. No changes in abundance of mRNAs for the BCODC E1 alpha, E1 beta and E2 subunits were detected by Northern-blot analysis. Likewise, dietary clofibric acid had no effect on the activity state of liver BCODC (percentage of enzyme in the dephosph...

Apports en DHA (acide gras oméga-3 par les poissons et les fruits de mer consommés en France

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Bourre Jean-Marie

2007-01-01

Full Text Available This present work measures the contributions of seafood (finfish and shellfish, wild and farmed to the intakes of DHA in France, year 2005, and consequently to the French recommended daily intakes (RDA of DHA. For this purpose, we measured the concentrations of DHA in each individual seafood by analysis of many published data. We also determined the exact consumption of the main products of seafood (fishing and farming in France (year 2005 using the modified method of the dietary intake measurement defined by the FAO. For year 2005, the 34 species of finfish and shellfish whose DHA contents are known account for 150% of the RDA of this omega-3 fatty acid. Taking all the species individually and extrapolating to include those whose DHA contents are not known, gives 156% of the RDA. The 10 greatest contributors to the DHA intake in the present diet are: salmon (47.6 mg/day/person, sardine (28.4, tuna (20.5, mackerel (15.7, herring (12.4, Alaskan pollock (8.9, cod (6.9, trout (6.5, hake (4.7, saithe (4.6. The 5 species of oily fish (salmon, sardine, tuna, mackerel and herring provide 63% of the DHA intake, and thus approx 95% of the French RDA. Besides DHA, seafood contains low amounts of ALA, but it can very high in farmed fish fed on rapeseed or linseed products. Omega-3 fatty acids (including EPA and DHA have an important role in human diet, both for prevention and the therapy of different pathologies. Data from many epidemiological studies has shown an inverse association between fish consumption, generally oily fish, and reductions in certain diseases. Although number of people do not lack dietary DHA, others, mainly pregnant women and nursing mothers and those people whose life styles or socio-economic positions restrict their seafood intakes, would benefit greatly from an increased intake of this omega-3 fatty acid.

Influence of adrenaline on the activity of succinate dehydrogenase in peripheral blood lymphocytes of irradiated rats

International Nuclear Information System (INIS)

Koroleva, L.V.; Vasin, M.V.

1988-01-01

In experiments with albino mongrel female rats, the influence of adrenaline on succinate dehydrogenase (SDG) activity in the peripheral blood lymphocytes of irradiated and intact animals has been investigated. Two minutes after the intraperitoneal administration of adrenaline (1 mg/kg) to intact rats SDG activity sharply rises and 3-4 min it drastically falls. In 6 to 8 min the second peak in the enzyme activity is registered. Twenty minutes after irradiation of rats in the crano-caudal direction with a dose of 75 Gy delivered to head, the reaction to adrenaline, manifested by the rise in SDG activity, is absent

Genome-wide association meta-analysis of fish and EPA+DHA consumption in 17 US and European cohorts.

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Dariush Mozaffarian

Full Text Available Regular fish and omega-3 consumption may have several health benefits and are recommended by major dietary guidelines. Yet, their intakes remain remarkably variable both within and across populations, which could partly owe to genetic influences.To identify common genetic variants that influence fish and dietary eicosapentaenoic acid plus docosahexaenoic acid (EPA+DHA consumption.We conducted genome-wide association (GWA meta-analysis of fish (n = 86,467 and EPA+DHA (n = 62,265 consumption in 17 cohorts of European descent from the CHARGE (Cohorts for Heart and Aging Research in Genomic Epidemiology Consortium Nutrition Working Group. Results from cohort-specific GWA analyses (additive model for fish and EPA+DHA consumption were adjusted for age, sex, energy intake, and population stratification, and meta-analyzed separately using fixed-effect meta-analysis with inverse variance weights (METAL software. Additionally, heritability was estimated in 2 cohorts.Heritability estimates for fish and EPA+DHA consumption ranged from 0.13-0.24 and 0.12-0.22, respectively. A significant GWA for fish intake was observed for rs9502823 on chromosome 6: each copy of the minor allele (FreqA = 0.015 was associated with 0.029 servings/day (~1 serving/month lower fish consumption (P = 1.96x10-8. No significant association was observed for EPA+DHA, although rs7206790 in the obesity-associated FTO gene was among top hits (P = 8.18x10-7. Post-hoc calculations demonstrated 95% statistical power to detect a genetic variant associated with effect size of 0.05% for fish and 0.08% for EPA+DHA.These novel findings suggest that non-genetic personal and environmental factors are principal determinants of the remarkable variation in fish consumption, representing modifiable targets for increasing intakes among all individuals. Genes underlying the signal at rs72838923 and mechanisms for the association warrant further investigation.

Whole-body DHA synthesis-secretion kinetics from plasma eicosapentaenoic acid and alpha-linolenic acid in the free-living rat.

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Metherel, Adam H; Domenichiello, Anthony F; Kitson, Alex P; Hopperton, Kathryn E; Bazinet, Richard P

2016-09-01

Whole body docosahexaenoic acid (DHA, 22:6n-3) synthesis from α-linolenic acid (ALA, 18:3n-3) is considered to be very low, however, the daily synthesis-secretion of DHA may be sufficient to supply the adult brain. The current study aims to assess whether whole body DHA synthesis-secretion kinetics are different when comparing plasma ALA versus eicosapentaenoic acid (EPA, 20:5n-3) as the precursor. Male Long Evans rats (n=6) were fed a 2% ALA in total fat diet for eight weeks, followed by surgery to implant a catheter into each of the jugular vein and carotid artery and 3h of steady-state infusion with a known amount of (2)H-ALA and (13)C-eicosapentaenoic acid (EPA, 20:5n3). Blood samples were collected at thirty-minute intervals and plasma enrichment of (2)H- and (13)C EPA, n-3 docosapentaenoic acid (DPAn-3, 22:5n-3) and DHA were determined for assessment of synthesis-secretion kinetic parameters. Results indicate a 13-fold higher synthesis-secretion coefficient for DHA from EPA as compared to ALA. However, after correcting for the 6.6 fold higher endogenous plasma ALA concentration, no significant differences in daily synthesis-secretion (nmol/day) of DHA (97.6±28.2 and 172±62), DPAn-3 (853±279 and 1139±484) or EPA (1587±592 and 1628±366) were observed from plasma unesterified ALA and EPA sources, respectively. These results suggest that typical diets which are significantly higher in ALA compared to EPA yield similar daily DHA synthesis-secretion despite a significantly higher synthesis-secretion coefficient from EPA. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

Identification, Cloning, and Characterization of l-Phenylserine Dehydrogenase from Pseudomonas syringae NK-15

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Sakuko Ueshima

2010-01-01

Full Text Available The gene encoding d-phenylserine dehydrogenase from Pseudomonas syringae NK-15 was identified, and a 9,246-bp nucleotide sequence containing the gene was sequenced. Six ORFs were confirmed in the sequenced region, four of which were predicted to form an operon. A homology search of each ORF predicted that orf3 encoded l-phenylserine dehydrogenase. Hence, orf3 was cloned and overexpressed in Escherichia coli cells and recombinant ORF3 was purified to homogeneity and characterized. The purified ORF3 enzyme showed l-phenylserine dehydrogenase activity. The enzymological properties and primary structure of l-phenylserine dehydrogenase (ORF3 were quite different from those of d-phenylserine dehydrogenase previously reported. l-Phenylserine dehydrogenase catalyzed the NAD+-dependent oxidation of the β-hydroxyl group of l-β-phenylserine. l-Phenylserine and l-threo-(2-thienylserine were good substrates for l-phenylserine dehydrogenase. The genes encoding l-phenylserine dehydrogenase and d-phenylserine dehydrogenase, which is induced by phenylserine, are located in a single operon. The reaction products of both enzymatic reactions were 2-aminoacetophenone and CO2.

Use of a novel docosahexaenoic acid formulation vs control in a neonatal porcine model of short bowel syndrome leads to greater intestinal absorption and higher systemic levels of DHA.

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Martin, Camilia R; Stoll, Barbara; Cluette-Brown, Joanne; Akinkuotu, Adesola C; Olutoye, Oluyinka O; Gura, Kathleen M; Singh, Pratibha; Zaman, Munir M; Perillo, Michael C; Puder, Mark; Freedman, Steven D; Burrin, Doug

2017-03-01

Infants with short bowel syndrome (SBS) are at high risk for malabsorption, malnutrition, and failure to thrive. The objective of this study was to evaluate in a porcine model of SBS, the systemic absorption of a novel enteral Docosahexaenoic acid (DHA) formulation that forms micelles independent of bile salts (DHA-ALT®). We hypothesized that enteral delivery of DHA-ALT® would result in higher blood levels of DHA compared to a control DHA preparation due to improved intestinal absorption. SBS was induced in term piglets through a 75% mid-jejunoileal resection and the piglets randomized to either DHA-ALT® or control DHA formulation (N=5 per group) for 4 postoperative days. The median±IQR difference in final vs starting weight was 696±425 g in the DHA-ALT® group compared to 132±278 g in the controls (P=.08). Within 12 hours, median±IQR DHA and eicosapentaenoic acid plasma levels (mol%) were significantly higher in the DHA-ALT® vs control group (4.1±0.3 vs 2.5±0.5, P=.009; 0.7±0.3 vs 0.2±0.005, P=.009, respectively). There were lower fecal losses of DHA and greater ileal tissue incorporation with DHA-ALT® vs the control. Morphometric analyses demonstrated an increase in proximal jejunum and distal ileum villus height in the DHA-ALT® group compared to controls (P=.01). In a neonatal porcine model of SBS, enteral administration of a novel DHA preparation that forms micelles independent of bile salts resulted in increased fatty acid absorption, increased ileal tissue incorporation, and increased systemic levels of DHA. Copyright © 2017 Elsevier Inc. All rights reserved.

Continuous gradient temperature Raman spectroscopy of n-6 DPA and DHA from -100 C to 20°C

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One of the great unanswered questions with respect to biological science in general is the absolute necessity of DHA in fast signal processing tissues. N-6 DPA, with just one less diene, group, is fairly abundant in terrestrial food chains yet cannot substitute for DHA. Gradient Temperature Raman sp...

Comparative study of the activity of lactate dehydrogenase (LDH) in different forms of disease

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Gonzalez Quesada, Jorge; Jorquera Cortez, Rodrigo; Rivera Alvarez, Sonia

2007-01-01

The activity of lactate dehydrogenase (LDH) was determined in the fluid gingival crevicular (FGC) from different sites of the anterior sector of the oral cavity in a clinically healthy subjects, and other with moderate gingivitis and with chronic severe generalized periodontists. Patients were treated and followed for three months, after the which has proceeded to make measurements of activity in the same sites discussed above. The results have showed statistically significant differences when comparing the activity of LDH in healthy individuals, and in other patients, treated by the pathology that presenting. On the other hand, were found without statistically significant differences between patients treated with clinically healthy subjects. The conclusion has been that the activity of LDH could be a quantitative marker for assessing cellular damage and evolution of treatment. (author) [es

Functional assignment of Glu386 and Arg388 in the active site of l-galactono-¿-lactone dehydrogenase

NARCIS (Netherlands)

Leferink, N.G.H.; Jose, M.D.F.; Berg, van den W.A.M.; Berkel, van W.J.H.

2009-01-01

The flavoenzyme l-galactono-¿-lactone dehydrogenase (GALDH) catalyzes the terminal step of vitamin C biosynthesis in plants. Little is known about the catalytic mechanism of GALDH and related aldonolactone oxidoreductases. Here we identified an essential Glu–Arg pair in the active site of GALDH from

Reaction rate studies of glucose-6-phosphate dehydrogenase activity in sections of rat liver using four tetrazolium salts

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Butcher, R. G.; van Noorden, C. J.

1985-01-01

The reaction rate of glucose-6-phosphate dehydrogenase activity in liver sections from fed and starved rats has been monitored by the continuous measurement at 37 degrees C of the reaction product as it is formed using scanning and integrating microdensitometry. Control media lacked either substrate

DHA supplementation for late onset Stargardt disease: NAT-3 study

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Giuseppe Querques

2010-06-01

Full Text Available Giuseppe Querques1, Pascale Benlian1, Bernard Chanu2, Nicolas Leveziel1, Gabriel Coscas1, Gisele Soubrane1, Eric H Souied11Department of Ophthalmology, University of Paris XII, Centre Hospitalier Intercommunal de Creteil, 2Department of Nutrition, University of Paris XII, Hopital Henry Mondor, Creteil, FranceBackground: We analyzed the effects of a docosahexaenoic acid (DHA supplementation in patients affected with late onset Stargardt disease (STGD.Methods: DHA (840 mg/day was given to 20 STGD patients for six months. A complete ophthalmologic examination, including best-corrected visual acuity (BCVA and multifocal electroretinogram (mfERG, was performed at inclusion day 0 (D0 and at month 6 (M6.Results: Overall, no statistical differences have been observed at M6 vs D0 as regards BCVA and mfERG (P > 0.05. Mild Improvement of BCVA and improvement of mfERG was noted in seven/40 eyes of four/20 patients. In the first patient, the peak of the a wave increased from 66 nV/deg² to 75.4 nV/deg² in the right eye (RE and 24.5 nV/deg² to 49.1 nV/deg² in the left eye (LE. The peak of the b wave improved from 122 nV/deg² to 157 nV/deg² in the RE, and 102 nV/deg² to 149 nV/deg² in the LE. In the second patient peaks of the a and b waves respectively increased from 11.8 nV/deg² to 72.1 nV/deg² and 53 nV/deg² to 185 nV/deg² in the RE. In the third patient the peak of the a wave increased from 37 nV/deg² to 43 nV/deg² in the RE, and from 31 nV/deg² to 45 nV/deg² in the LE; the peak of the b wave improved from 70 nV/deg² to 89 nV/deg² in the RE, and from 101 nV/deg² to 108 nV/deg² in the LE. In the fourth patient, the peak of the a wave increased from 39 nV/deg² to 42 nV/deg² in the RE, and from 40 nV/deg² to 43 nV/deg² in the LE; the peak of the b wave improved from 86 nV/deg² to 94 nV/deg² in the RE, and from 87 nV/deg² to 107 nV/deg² in the LE.Conclusion: DHA seems to influence some functional parameters in patients affected with

The hydroxylated form of docosahexaenoic acid (DHA-H) modifies the brain lipid composition in a model of Alzheimer's disease, improving behavioral motor function and survival.

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Mohaibes, Raheem J; Fiol-deRoque, María A; Torres, Manuel; Ordinas, Margarita; López, David J; Castro, José A; Escribá, Pablo V; Busquets, Xavier

2017-09-01

We have compared the effect of the commonly used ω-3 fatty acid, docosahexaenoic acid ethyl ester (DHA-EE), and of its 2-hydroxylated DHA form (DHA-H), on brain lipid composition, behavior and lifespan in a new human transgenic Drosophila melanogaster model of Alzheimer's disease (AD). The transgenic flies expressed human Aβ42 and tau, and the overexpression of these human transgenes in the CNS of these flies produced progressive defects in motor function (antigeotaxic behavior) while reducing the animal's lifespan. Here, we demonstrate that both DHA-EE and DHA-H increase the longer chain fatty acids (≥18C) species in the heads of the flies, although only DHA-H produced an unknown chromatographic peak that corresponded to a non-hydroxylated lipid. In addition, only treatment with DHA-H prevented the abnormal climbing behavior and enhanced the lifespan of these transgenic flies. These benefits of DHA-H were confirmed in the well characterized transgenic PS1/APP mouse model of familial AD (5xFAD mice), mice that develop defects in spatial learning and in memory, as well as behavioral deficits. Hence, it appears that the modulation of brain lipid composition by DHA-H could have remedial effects on AD associated neurodegeneration. This article is part of a Special Issue entitled: Membrane Lipid Therapy: Drugs Targeting Biomembranes edited by Pablo V. Escribá. Copyright © 2017. Published by Elsevier B.V.

Cytophotometry of glucose-6-phosphate dehydrogenase activity in individual cells

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van Noorden, C. J.; Tas, J.; Vogels, I. M.

1983-01-01

With the aid of thin films of polyacrylamide gel containing purified glucose-6-phosphate dehydrogenase subjected to cytochemical procedures for the enzyme using tetranitro blue tetrazolium, arbitrary units of integrated absorbance obtained with a Barr & Stroud GN5 cytophotometer were converted into

Effect of Punica granatum fruit peel on glucose-6-phosphate dehydrogenase and malate dehydrogenase in amphistome Gastrothylax indicus.

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Aggarwal, Rama; Bagai, Upma

2017-03-01

Increasing anthelmintic resistance and the impact of conventional anthelmintics on the environment, it is important to look for alternative strategies against helminth parasite in sheep. Important lipogenic enzymes like glucose-6-phosphate dehydrogenase (G-6-PDH) and malate dehydrogenase (MDH) show subcellular distribution pattern. Activity of G-6-PDH was largely restricted to cytosolic fraction while MDH was found in both cytosolic and mitochondrial fraction in Gastrothylax indicus. Following in vitro treatment with ethanolic and aqueous extracts of Punica granatum fruit peel and commercial anthelmintic, albendazole G-6-PDH activity was decreased by 19-32 %, whereas MDH was suppressed by 24-41 %, compared to the respective control. Albendazole was quite effective when compared with negative control and both the extracts. The results indicate that phytochemicals of plant may act as potential vermifuge or vermicide.

Analysing the dhaT gene in Colombian Clostridium sp. (Clostridia 1,3-propanediol-producing strains

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Diana Milena Quilaguy-Ayure

2010-04-01

Full Text Available To analyze the dhaT gene, one of the genes responsible for the 1,3-propanediol (1,3-PD production, in two native Clostridiumstrains. Materials and methods: The dhaT gene was amplified by Polimerase Chain Reaction with specific primers designed fromClostridium butyricum VPI1718 operon. Bioinformatics tools like BLASTN, ORF finder, BLASTP and ClustalW were used to determinethe identity of the sequence and to assign a function. Results: DNA amplification products were obtained from Colombian Clostridium sp.native strains (IBUN 13A and IBUN 158B and the Clostridium butyricum DSM 2478 strain, which were sequenced. According to thebioinformatics analysis of the above sequences, a high degree of similarity was found with the dhaT gene of different bacterial species. Thehighest percentage of identity was obtained with the Clostridium butyricum VPI 1718 strain. Conclusion: knowledge of the physicalstructure of the 1,3-PD operon in native strains opens the way for developing genetic and metabolic engineering strategies for improvingprocesses productivity.

Production of Structured Phosphatidylcholine with High Content of DHA/EPA by Immobilized Phospholipase A1-Catalyzed Transesterification

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Xiang Li

2014-08-01

Full Text Available This paper presents the synthesis of structured phosphatidylcholine (PC enriched with docosahexaenoic acid (DHA and eicosapentaenoic acid (EPA by transesterification of DHA/EPA-rich ethyl esters with PC using immobilized phospholipsase A1 (PLA1 in solvent-free medium. Firstly, liquid PLA1 was immobilized on resin D380, and it was found that a pH of 5 and a support/PLA1 ratio (w/v of 1:3 were the best conditions for the adsorption. Secondly, the immobilized PLA1 was used to catalyze transesterification of PC and DHA/EPA-rich ethyl esters. The maximal incorporation of DHA and EPA achieved was 30.7% for 24 h of reaction at 55 °C using a substrate mass ratio (PC/ethyl esters of 1:6, an immobilized PLA1 loading of 15% and water dosage of 1.25%. Then the reaction mixture was analyzed by 31P nuclear magnetic resonance (NMR. The composition of reaction product included 16.5% PC, 26.3% 2-diacyl-sn-glycero-3-lysophosphatidylcholine (1-LPC, 31.4% 1-diacyl-sn-glycero-3-lysophosphatidylcholine (2-LPC, and 25.8% sn-glycerol-3-phosphatidylcholine (GPC.

Effects of DHA-enriched hen egg yolk and L-cysteine supplementation on quality of cryopreserved boar semen.

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Chanapiwat, Panida; Kaeoket, Kampon; Tummaruk, Padet

2009-09-01

The objective of the present study was to determine the effects of docosahexaenoic acid (DHA)-enriched hen egg yolks and L-cysteine supplementation on the qualities of the cryopreserved boar semen. A total of 15 ejaculates from 5 Pietrain boars were divided into 4 groups according to the compositions of the freezing extenders used, that is, normal hen egg yolk (group I), DHA-enriched hen egg yolk (group II), normal hen egg yolk with 5 mmol L(-1) of cysteine supplementation (group III) and DHA-enriched hen egg yolk with 5 mmol L(-1) of cysteine supplementation (group IV). The semen was cryopreserved using controlled rate freezer and was thawed at 50 degrees C for 12 s. Progressive motility, sperm viability, acrosome integrity and functional integrity of sperm plasma membrane of the post-thawed semen were evaluated. The supplementation of L-cysteine in the freezing extender alone (group III) improved progressive motility (P semen qualities (P > 0.05). In conclusion, the supplementation of antioxidant L-cysteine alone or in combination with DHA-enriched hen egg yolk significantly improved the post-thawed semen qualities, especially progressive motility and acrosome integrity.

PEMANFAATAN MIKROALGA LAUT Chlorella vulgaris SUMBER DHA DAN EPA

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Anggraeni, Peni

2016-01-01

Penelitian tentang mikroalga laut jenis Chlorella vulgaris telah dilakukan. Chlorella vulgaris dipilih sebagai bahan penambah gizi untuk di fortifikasi kedalam makanan . Penelitian ini bertujuan untuk mengetahui kandungan gizi dengan menganalisis kandungan DHA dan EPA. Penelitian ini dilakukan dengan mengkultur fitoplankton Chlorella vulgaris dan dipanen setelah media kultur mencapai fase Stasioner. Kemudian, dikeringkan dengan menggunakan freeze dryer, biomassa kering dianalisis kandungan DH...

The Pattern of Fatty Acids Displaced by EPA and DHA Following 12 Months Supplementation Varies between Blood Cell and Plasma Fractions

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Walker, Celia G.; West, Annette L.; Browning, Lucy M.; Madden, Jackie; Gambell, Joanna M.; Jebb, Susan A.; Calder, Philip C.

2015-01-01

Eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) are increased in plasma lipids and blood cell membranes in response to supplementation. Whilst arachidonic acid (AA) is correspondingly decreased, the effect on other fatty acids (FA) is less well described and there may be site-specific differences. In response to 12 months EPA + DHA supplementation in doses equivalent to 0–4 portions of oily fish/week (1 portion: 3.27 g EPA+DHA) multinomial regression analysis was used to identify...

Characterization of docosahexaenoic acid (DHA)-induced heme oxygenase-1 (HO-1) expression in human cancer cells: the importance of enhanced BTB and CNC homology 1 (Bach1) degradation.

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Wang, Shuai; Hannafon, Bethany N; Wolf, Roman F; Zhou, Jundong; Avery, Jori E; Wu, Jinchang; Lind, Stuart E; Ding, Wei-Qun

2014-05-01

The effect of docosahexaenoic acid (DHA) on heme oxygenase-1 (HO-1) expression in cancer cells has never been characterized. This study examines DHA-induced HO-1 expression in human cancer cell model systems. DHA enhanced HO-1 gene expression in a time- and concentration-dependent manner, with maximal induction at 21 h of treatment. This induction of HO-1 expression was confirmed in vivo using a xenograft nude mouse model fed a fish-oil-enriched diet. The increase in HO-1 gene transcription induced by DHA was significantly attenuated by the antioxidant N-acetyl cysteine, suggesting the involvement of oxidative stress. This was supported by direct measurement of lipid peroxide levels after DHA treatment. Using a human HO-1 gene promoter reporter construct, we identified two antioxidant response elements (AREs) that mediate the DHA-induced increase in HO-1 gene transcription. Knockdown of nuclear factor (erythroid-derived 2)-like 2 (Nrf2) expression compromised the DHA-induced increase in HO-1 gene transcription, indicating the importance of the Nrf2 pathway in this event. However, the nuclear protein levels of Nrf2 remained unchanged upon DHA treatment. Further studies demonstrated that DHA reduces nuclear Bach1 protein expression by promoting its degradation and attenuates Bach1 binding to the AREs in the HO-1 gene promoter. In contrast, DHA enhanced Nrf2 binding to the AREs without affecting nuclear Nrf2 expression levels, indicating a new cellular mechanism that mediates DHA's induction of HO-1 gene transcription. To our knowledge, this is the first characterization of DHA-induced HO-1 expression in human malignant cells. Copyright © 2014 Elsevier Inc. All rights reserved.

Long-chain omega-3 fatty acids and the brain: a review of the independent and shared effects of EPA, DPA and DHA.

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Dyall, Simon C

2015-01-01

Omega-3 polyunsaturated fatty acids (PUFAs) exhibit neuroprotective properties and represent a potential treatment for a variety of neurodegenerative and neurological disorders. However, traditionally there has been a lack of discrimination between the different omega-3 PUFAs and effects have been broadly accredited to the series as a whole. Evidence for unique effects of eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA) and more recently docosapentaenoic acid (DPA) is growing. For example, beneficial effects in mood disorders have more consistently been reported in clinical trials using EPA; whereas, with neurodegenerative conditions such as Alzheimer's disease, the focus has been on DHA. DHA is quantitatively the most important omega-3 PUFA in the brain, and consequently the most studied, whereas the availability of high purity DPA preparations has been extremely limited until recently, limiting research into its effects. However, there is now a growing body of evidence indicating both independent and shared effects of EPA, DPA and DHA. The purpose of this review is to highlight how a detailed understanding of these effects is essential to improving understanding of their therapeutic potential. The review begins with an overview of omega-3 PUFA biochemistry and metabolism, with particular focus on the central nervous system (CNS), where DHA has unique and indispensable roles in neuronal membranes with levels preserved by multiple mechanisms. This is followed by a review of the different enzyme-derived anti-inflammatory mediators produced from EPA, DPA and DHA. Lastly, the relative protective effects of EPA, DPA and DHA in normal brain aging and the most common neurodegenerative disorders are discussed. With a greater understanding of the individual roles of EPA, DPA and DHA in brain health and repair it is hoped that appropriate dietary recommendations can be established and therapeutic interventions can be more targeted and refined.

Soy-based infant formula supplemented with DHA and ARA supports growth and increases circulating levels of these fatty acids in infants.

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Hoffman, Dennis; Ziegler, Ekhard; Mitmesser, Susan H; Harris, Cheryl L; Diersen-Schade, Deborah A

2008-01-01

Healthy term infants (n = 244) were randomized to receive: (1) control, soy-based formula without supplementation or (2) docosahexaenoic acid-arachidonic acid (DHA + ARA), soy-based formula supplemented with at least 17 mg DHA/100 kcal (from algal oil) and 34 mg ARA/100 kcal (from fungal oil) in a double-blind, parallel group trial to evaluate safety, benefits, and growth from 14 to 120 days of age. Anthropometric measurements were taken at 14, 30, 60, 90, and 120 days of age and 24-h dietary and tolerance recall were recorded at 30, 60, 90, and 120 days of age. Adverse events were recorded throughout the study. Blood samples were drawn from subsets of 25 infants in each group. Capillary column gas chromatography was used to analyze the percentages of fatty acids in red blood cell (RBC) lipids and plasma phospholipids. Compared with the control group, percentages of fatty acids such as DHA and ARA in total RBC and plasma phospholipids were significantly higher in infants in the DHA + ARA group at 120 days of age (P soy-based formula supplemented with DHA and ARA from single cell oil sources at concentrations similar to human milk significantly increased circulating levels of DHA and ARA when compared with the control group. Both formulas supported normal growth and were well tolerated.

Pyruvate dehydrogenase complex and lactate dehydrogenase as targets for therapy of acute liver failure.

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Ferriero, Rosa; Nusco, Edoardo; De Cegli, Rossella; Carissimo, Annamaria; Manco, Giuseppe; Brunetti-Pierri, Nicola

2018-03-23

Acute liver failure is a rapidly progressive deterioration of hepatic function resulting in high mortality and morbidity. Metabolic enzymes can translocate in the nucleus to regulate histone acetylation and gene expression. Levels and activities of pyruvate dehydrogenase complex (PDHC) and lactate dehydrogenase (LDH) were evaluated in nuclear fractions of livers of mice exposed to various hepatotoxins including CD95-Ab, α-amanitin, and acetaminophen. Whole-genome gene expression profiling by RNA-seq was performed in livers of mice with acute liver failure and analyzed by Gene Ontology Enrichment Analysis. Efficacy of histone acetyltransferase inhibitor garcinol and LDH inhibitor galloflavin at reducing liver damage was evaluated in mice with induced hepatotoxicity. Levels and activities of PDHC and LDH were increased in cytoplasmatic and nuclear fractions of livers of mice with acute liver failure. The increase of nuclear PDHC and LDH was associated with increased concentrations of acetyl-coA and lactate in nuclear fractions, and histone H3 hyper-acetylation. Gene expression in livers of mice with acute liver failure suggested that increased histone H3 acetylation induces the expression of genes related to response to damage. Reduced histone acetylation by the histone acetyltransferase inhibitor garcinol decreased liver damage and improved survival in mice with acute liver failure. Knock-down of PDHC or LDH improved viability in cells exposed to a pro-apoptotic stimulus. Treatment with the LDH inhibitor galloflavin that was also found to inhibit PDHC, reduced hepatic necrosis, apoptosis, and expression of pro-inflammatory cytokines in mice with acute liver failure. Mice treated with galloflavin also showed a dose-response increase in survival. PDHC and LDH translocate to the nucleus and are targets for therapy of acute liver failure. Acute liver failure is a rapidly progressive and life-threatening deterioration of liver function resulting in high mortality and

Cellular distribution, purification and electrophoretic properties of malate dehydrogenase in Trichuris ovis and inhibition by benzimidazoles and pyrimidine derivatives.

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Sanchez-Moreno, M; Ortega, J E; Valero, A

1989-12-01

High levels of malate dehydrogenase were found in Trichuris ovis. Two molecular forms of the enzyme, of different cellular location and electrophoretic pattern, were isolated and purified. The activity of soluble malate dehydrogenase was greater than that of mitochondrial malate dehydrogenase. Both forms also displayed different electrophoretic profiles in comparison with purified extracts from goat (Capra hircus) liver. Substrate concentration directly affected enzyme activity. Host and parasite malate dehydrogenase activity were both inhibited by a series of benzimidazoles and pyrimidine-derived compounds, some of which markedly reduced parasite enzyme activity, but not host enzyme activity. Percentage inhibition by some pyrimidine derivatives was greater than that produced by benzimidazoles.

Complete assessment of whole-body n-3 and n-6 PUFA synthesis-secretion kinetics and DHA turnover in a rodent model.

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Metherel, Adam H; Lacombe, R J Scott; Chouinard-Watkins, Raphaël; Hopperton, Kathryn E; Bazinet, Richard P

2018-02-01

Previous assessments of the PUFA biosynthesis pathway have focused on DHA and arachidonic acid synthesis. Here, we determined whole-body synthesis-secretion kinetics for all downstream products of PUFA metabolism, including direct measurements of DHA and n-6 docosapentaenoic acid (DPAn-6, 22:5n-6) turnover, and compared n-6 and n-3 homolog kinetics. We infused labeled α-linolenic acid (ALA, 18:3n-3), linoleic acid (LNA, 18:2n-6), DHA, and DPAn-6 as 2 H 5 -ALA, 13 C 18 -LNA, 13 C 22 -DHA, and 13 C 22 -DPAn-6. Eight 11-week-old Long Evans rats fed a 10% fat diet were infused with the labeled PUFAs over 3 h, and plasma enrichment of labeled products was measured every 30 min. The DHA synthesis-secretion rate (94 ± 34 nmol/day) did not differ from other PUFA products (range, 21.8 ± 4.3 nmol/day to 408 ± 116 nmol/day). Synthesis-secretion rates of n-6 and n-3 PUFA homologs were similar, except 22:4n-6 and DPAn-6 had lower synthesis rates. However, daily turnover from newly synthesized DHA (0.067 ± 0.023%) was 56-fold to 556-fold slower than all other PUFA turnover and was 130-fold slower than that determined directly from the total plasma unesterified DHA pool. In conclusion, n-6 and n-3 PUFA synthesis-secretion kinetics suggest that differences in turnover, not in synthesis-secretion rates, primarily determine PUFA plasma levels. Copyright © 2018 by the American Society for Biochemistry and Molecular Biology, Inc.

The establishment of new control parameters in the aerobic stabilisation of sludge; Establecimiento de nuevos parametros de control en la estabilizacion aerobia de lodos

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Barragan Sanchez, J.; Coello Oviedo, M. D.; Cruz Romero, F. J.; Quiroga Alonso, J. M.

2002-07-01

This article presents the results obtained in an aerobic sludge digestion process in a conventional waste water treatment plant employing the usual parameters in this type of study as discussed in the literature. The physicochemical parameters used were pH dissolved oxygen, temperature. Chemical Demand for Oxygen (DOQ) total solids (TS) and volatile solids (VS), while the microbiological parameters were fecal coliforms Escherichia coli (EC) and the active and total bacteria counts. The enzymatic parameters examined were the specific oxygen uptake rate (SOUR). In dehydrogenase (DHA) activity and esterase activity (EA). The results obtained permit the conclusions that although physicochemical parameters provide information on the system's performance, they are neither indicative of the degree of endogenesis attained nor representative of the factors affecting the process. The microbiological parameters, on the other hand, are valid as measurements of the evolution of the populations and of the factors affecting them, but are not representative of the endogenous breathing process. besides which they also present problems of quantification. Finally, the enzymatic parameters, dehydrogenase activity and, especially, the DHA/EA ratio, are an efficient tool. Since they are representative of the metabolic state of the sludge, it is possible to establish criteria regarding its stability in relation to the mixed feed sludge. (Author) 11 refs.

DHA down-regulates phenobarbital-induced cytochrome P450 2B1 gene expression in rat primary hepatocytes by attenuating CAR translocation

International Nuclear Information System (INIS)

Li, C.-C.; Lii, C.-K.; Liu, K.-L.; Yang, J.-J.; Chen, H.-W.

2007-01-01

The constitutive androstane receptor (CAR) plays an important role in regulating the expression of detoxifying enzymes, including cytochrome P450 2B (CYP 2B). Phenobarbital (PB) induction of human CYP 2B6 and mouse CYP 2b10 has been shown to be mediated by CAR. Our previous study showed that PB-induced CYP 2B1 expression in rat primary hepatocytes is down-regulated by both n-6 and n-3 polyunsaturated fatty acids (PUFAs), especially docosahexaenoic acid (DHA); however, the mechanism for this down-regulation by DHA was previously unknown. The objective of the present study was to determine whether change in CAR translocation is involved in the down-regulation by n-6 and n-3 PUFAs of PB-induced CYP 2B1 expression in rat primary hepatocytes. We used 100 μM arachidonic acid, linoleic acid, eicosapentaenoic acid, and DHA to test this hypothesis. PB triggered the translocation of CAR from the cytosol into the nucleus in a dose-dependent and time-dependent manner in our hepatocyte system, and the CAR distribution in rat primary hepatocytes was significantly affected by DHA. DHA treatment decreased PB-inducible accumulation of CAR in the nuclear fraction and increased it in the cytosolic fraction in a dose-dependent manner. The down-regulation of CYP 2B1 expression by DHA occurred in a dose-dependent manner, and a similar pattern was found for the nuclear accumulation of CAR. The results of immunoprecipitation showed a CAR/RXR heterodimer bound to nuclear receptor binding site 1 (NR-1) of the PB-responsive enhancer module (PBREM) of the CYP 2B1gene. The EMSA results showed that PB-induced CAR binding to NR-1 was attenuated by DHA. Taken together, these results suggest that attenuation of CAR translocation and decreased subsequent binding to NR-1 are involved in DHA's down-regulation of PB-induced CYP 2B1 expression

Chronic dietary n-6 PUFA deprivation leads to conservation of arachidonic acid and more rapid loss of DHA in rat brain phospholipids.

Science.gov (United States)

Lin, Lauren E; Chen, Chuck T; Hildebrand, Kayla D; Liu, Zhen; Hopperton, Kathryn E; Bazinet, Richard P

2015-02-01

To determine how the level of dietary n-6 PUFA affects the rate of loss of arachidonic acid (ARA) and DHA in brain phospholipids, male rats were fed either a deprived or adequate n-6 PUFA diet for 15 weeks postweaning, and then subjected to an intracerebroventricular infusion of (3)H-ARA or (3)H-DHA. Brains were collected at fixed times over 128 days to determine half-lives and the rates of loss from brain phospholipids (J out). Compared with the adequate n-6 PUFA rats, the deprived n-6-PUFA rats had a 15% lower concentration of ARA and an 18% higher concentration of DHA in their brain total phospholipids. Loss half-lives of ARA in brain total phospholipids and fractions (except phosphatidylserine) were longer in the deprived n-6 PUFA rats, whereas the J out was decreased. In the deprived versus adequate n-6 PUFA rats, the J out of DHA was higher. In conclusion, chronic n-6 PUFA deprivation decreases the rate of loss of ARA and increases the rate of loss of DHA in brain phospholipids. Thus, a low n-6 PUFA diet can be used to target brain ARA and DHA metabolism. Copyright © 2015 by the American Society for Biochemistry and Molecular Biology, Inc.

Physiological regulation of isocitrate dehydrogenase and the role of 2-oxoglutarate in Prochlorococcus sp. strain PCC 9511.

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María Agustina Domínguez-Martín

Full Text Available The enzyme isocitrate dehydrogenase (ICDH; EC 1.1.1.42 catalyzes the oxidative decarboxylation of isocitrate, to produce 2-oxoglutarate. The incompleteness of the tricarboxylic acids cycle in marine cyanobacteria confers a special importance to isocitrate dehydrogenase in the C/N balance, since 2-oxoglutarate can only be metabolized through the glutamine synthetase/glutamate synthase pathway. The physiological regulation of isocitrate dehydrogenase was studied in cultures of Prochlorococcus sp. strain PCC 9511, by measuring enzyme activity and concentration using the NADPH production assay and Western blotting, respectively. The enzyme activity showed little changes under nitrogen or phosphorus starvation, or upon addition of the inhibitors DCMU, DBMIB and MSX. Azaserine, an inhibitor of glutamate synthase, induced clear increases in the isocitrate dehydrogenase activity and icd gene expression after 24 h, and also in the 2-oxoglutarate concentration. Iron starvation had the most significant effect, inducing a complete loss of isocitrate dehydrogenase activity, possibly mediated by a process of oxidative inactivation, while its concentration was unaffected. Our results suggest that isocitrate dehydrogenase responds to changes in the intracellular concentration of 2-oxoglutarate and to the redox status of the cells in Prochlorococcus.

Reduction of n-3 PUFAs, specifically DHA and EPA, and enhancement of peroxisomal beta-oxidation in type 2 diabetic rat heart

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Hou Lianguo

2012-10-01

Full Text Available Abstract Background There is overwhelming evidence that dietary supplementation with n-3 polyunsaturated fatty acids (PUFAs, mainly EPA (C20:5n-3 and DHA (C22:6n-3, has cardiovascular protective effects on patients with type 2 diabetes mellitus (T2DM but not on healthy people. Because the T2DM heart increases fatty acid oxidation (FAO to compensate for the diminished utilization of glucose, we hypothesize that T2DM hearts consume more n-3 PUFAs and, therefore, need more n-3 PUFAs. In the present study, we investigated the changes in cardiac n-3 PUFAs and peroxisomal beta-oxidation, which are responsible for the degradation of PUFAs in a high-fat diet (HFD and low-dose streptozotocin- (STZ induced type 2 diabetic rat model. Methods and results The capillary gas chromatography results showed that all the n-3 (or omega-3 PUFAs, especially DHA (~50% and EPA (~100%, were significantly decreased, and the n-6/n-3 ratio (~115% was significantly increased in the hearts of diabetic rats. The activity of peroxisomal beta-oxidation, which is crucial to very-long-chain and unsaturated FA metabolism (including DHA, was significantly elevated in DM hearts. Additionally, the real-time PCR results showed that the mRNA expression of most peroxisomal beta-oxidation key enzymes were up-regulated in T2DM rat hearts, which might contribute to the reduction of n-3 (or omega-3 PUFAs. Conclusion In conclusion, our results indicate that T2DM hearts consume more n-3 PUFAs, especially DHA and EPA, due to exaggerated peroxisomal beta-oxidation.

Crystallization and crystallographic analysis of the Rhodococcus rhodochrous NCIMB 13064 DhaA mutant DhaA31 and its complex with 1,2,3-trichloropropane

Czech Academy of Sciences Publication Activity Database

Lahoda, M.; Chaloupková, R.; Stsiapanava, A.; Damborský, J.; Kutá-Smatanová, Ivana

2011-01-01

Roč. 67, Part 3 (2011), s. 397-400 ISSN 1744-3091 R&D Projects: GA MŠk(CZ) LC06010; GA MŠk(CZ) ED1.1.00/02.0073 Institutional research plan: CEZ:AV0Z60870520 Keywords : haloalkane dehalogenases * DhaA * Rhodococcus rhodochrous Subject RIV: CE - Biochemistry Impact factor: 0.506, year: 2011

DHA Supplementation Alone or in Combination with Other Nutrients Does not Modulate Cerebral Hemodynamics or Cognitive Function in Healthy Older Adults

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Philippa A. Jackson

2016-02-01

Full Text Available A number of recent trials have demonstrated positive effects of dietary supplementation with the omega-3 polyunsaturated fatty acids (n-3 PUFAs, docosahexaenoic acid (DHA and eicosapentaenoic acid (EPA on measures of cognitive function in healthy young and older adults. One potential mechanism by which EPA, and DHA in particular, may exert these effects is via modulation of cerebral hemodynamics. In order to investigate the effects of DHA alone or provided as one component of a multinutrient supplement (also including Gingko biloba, phosphatidylserine and vitamins B9 and B12 on measures of cerebral hemodynamics and cognitive function, 86 healthy older adults aged 50–70 years who reported subjective memory deficits were recruited to take part in a six month daily dietary supplementation trial. Relative changes in the concentration of oxygenated hemoglobin and deoxygenated hemoglobin were assessed using Near Infrared Spectroscopy (NIRS during the performance of cognitive tasks prior to and following the intervention period. Performance on the cognitive tasks was also assessed. No effect of either active treatment was found for any of the NIRS measures or on the cognitive performance tasks, although the study was limited by a number of factors. Further work should continue to evaluate more holistic approaches to cognitive aging.

Determination of Partial Molar Volumes of EPA and DHA Ethyl Esters in Supercritical Carbon Dioxide

Institute of Scientific and Technical Information of China (English)

无

2002-01-01

The use of supercritical-fluid chromatography for determining partial molar volumes of ethyl esters of cis-5,8,11,14,17-eicosapentaenoic acid (EPA) and cis -4,7,10,13,16,19- docosa-hexaenoic acid (DHA) in supercritical carbon dioxide is presented and discussed. Partial molar volumes of EPA and DHA esters are obtained from the variation of the retention properties with the density of mobile phase at 313.15 K, 323.15 K, 333.15 K and in the pressure range from 9 MPa to 21 MPa.

Deptermination of Partial Molar Volumes of EPA and DHA Ethyl Esters in Supercritical Carbon Dioxide

Institute of Scientific and Technical Information of China (English)

MeiHUANG; XianDaWANG; 等

2002-01-01

The use of supercritical-fluid shromatogrphy for determining partial molar volumes of ethyl esters of cis-5,8,11,14,17-eicosapentaenoic acid (EPA) and cis-4,7,10,13,16,19-docosa-hexaenoic acid(DHA) in supercritical carbon dioxide is presented and discussed. Partial molar volumes of EPA and DHA esters are obtained from the variation of the retention properties with the density of mobile phase at 313.15K,323.15K,333.15K and in the pressure range from 9 MPa to 21 MPa.

NAD(P-DEPENDENT DEHYDROGENASE ACTIVITY IN PERIPHERAL BLOOD LYMPHOCYTES OF INFANTS WITH ENLARGEMENT OF PHARYNGEAL TONSILS

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L. M. Kurtasova

2014-01-01

Full Text Available We have observed and examined 57 children 1 to 3 years old diagnosed with enlargement of pharyngeal tonsils. A control group was presented by 35 healthy children. Bioluminescence technique was applied for studying NAD(P-dependent dehydrogenase activity in peripheral blood lymphocytes. Activation of aerobic respiration and increasing activity of pentose phosphate cycle-dependent plastic processes were registered in blood lymphocytes of children with hypertrophic pharyngeal tonsils; along with decreased function of malate-aspartate shunt in energy metabolism of the cells, diminished anaerobic reaction of NADHdependent LDH, lower interaction between Krebs cycle and reactions of amino acid metabolism, and reduced activity of glutathione reductase.

Multiple alcohol dehydrogenases but no functional acetaldehyde dehydrogenase causing excessive acetaldehyde production from ethanol by oral streptococci.

Science.gov (United States)

Pavlova, Sylvia I; Jin, Ling; Gasparovich, Stephen R; Tao, Lin

2013-07-01

Ethanol consumption and poor oral hygiene are risk factors for oral and oesophageal cancers. Although oral streptococci have been found to produce excessive acetaldehyde from ethanol, little is known about the mechanism by which this carcinogen is produced. By screening 52 strains of diverse oral streptococcal species, we identified Streptococcus gordonii V2016 that produced the most acetaldehyde from ethanol. We then constructed gene deletion mutants in this strain and analysed them for alcohol and acetaldehyde dehydrogenases by zymograms. The results showed that S. gordonii V2016 expressed three primary alcohol dehydrogenases, AdhA, AdhB and AdhE, which all oxidize ethanol to acetaldehyde, but their preferred substrates were 1-propanol, 1-butanol and ethanol, respectively. Two additional dehydrogenases, S-AdhA and TdhA, were identified with specificities to the secondary alcohol 2-propanol and threonine, respectively, but not to ethanol. S. gordonii V2016 did not show a detectable acetaldehyde dehydrogenase even though its adhE gene encodes a putative bifunctional acetaldehyde/alcohol dehydrogenase. Mutants with adhE deletion showed greater tolerance to ethanol in comparison with the wild-type and mutant with adhA or adhB deletion, indicating that AdhE is the major alcohol dehydrogenase in S. gordonii. Analysis of 19 additional strains of S. gordonii, S. mitis, S. oralis, S. salivarius and S. sanguinis showed expressions of up to three alcohol dehydrogenases, but none showed detectable acetaldehyde dehydrogenase, except one strain that showed a novel ALDH. Therefore, expression of multiple alcohol dehydrogenases but no functional acetaldehyde dehydrogenase may contribute to excessive production of acetaldehyde from ethanol by certain oral streptococci.

Pyruvate Dehydrogenase and Pyruvate Dehydrogenase Kinase Expression in Non Small Cell Lung Cancer and Tumor-Associated Stroma

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Michael I. Koukourakis

2005-01-01

Full Text Available 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 HIFia stabilization and induction of anaerobic metabolism, recent data suggest that high pyruvate concentrations also result in HIFia 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 HIFia stabilization and “aerobic glycolysis.” However, about half of PDHdeficient 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.

Effects of aspirin in combination with EPA and DHA on HDL-C cholesterol and ApoA1 exchange in individuals with type 2 diabetes mellitus.

Science.gov (United States)

Block, Robert C; Holub, Ashley; Abdolahi, Amir; Tu, Xin M; Mousa, Shaker A; Oda, Michael N

2017-11-01

Low-dose aspirin is an effective drug for the prevention of cardiovascular disease (CVD) events but individuals with diabetes mellitus can be subject to 'aspirin resistance'. Thus, aspirin's effect in these individuals is controversial. Higher blood levels of seafood-derived omega-3 polyunsaturated fatty acids (ω3) eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) also have beneficial effects in reducing risk of CVD events but few studies have examined the interaction of plasma EPA and DHA with aspirin ingestion. Our study examined the combinatory effects of EPA, DHA, and aspirin ingestion on HDL-cholesterol (HDL-C) and apoA-I exchange (shown to be associated with CVD event risk). 30 adults with Type 2 diabetes mellitus ingested aspirin (81mg/day) for 7 consecutive days, EPA+DHA (2.6g/day) for 28 days, then both for 7 days. Plasma was collected at baseline and at 5 subsequent visits including 4h after each aspirin ingestion. Mixed model methods were used to determine HDL-C-concentrations and apoA-I exchange compared to the baseline visit values. LOWESS curves were used for non-linear analyses of outcomes to help discern change patterns, which was followed by piecewise linear functions for formal testing of curvilinear relationships. Significant changes (p aspirin-only ingestion, apoA-I exchange was significantly modified by increasing levels of DHA concentration, with increased apoA-I exchange observed up until log(DHA) of 4.6 and decreased exchange thereafter (p = 0.03). These LOWESS curve effects were not observed for EPA or HDL-C (p > 0.05). Aspirin's effects on apoA-I exchange were the greatest when EPA or DHA concentrations were moderate compared to high or low. Comparison of EPA, DHA, and EPA+DHA LOWESS curves, demonstrated that the majority of the effect is due to DHA. Our results strongly suggest that plasma concentrations of EPA and DHA influence aspirin effects on lipid mediators of CVD event risk where their concentrations are most beneficial

Purification and characterization of xylitol dehydrogenase with l-arabitol dehydrogenase activity from the newly isolated pentose-fermenting yeast Meyerozyma caribbica 5XY2.

Science.gov (United States)

Sukpipat, Wiphat; Komeda, Hidenobu; Prasertsan, Poonsuk; Asano, Yasuhisa

2017-01-01

Meyerozyma caribbica strain 5XY2, which was isolated from an alcohol fermentation starter in Thailand, was found to catabolize l-arabinose as well as d-glucose and d-xylose. The highest production amounts of ethanol from d-glucose, xylitol from d-xylose, and l-arabitol from l-arabinose were 0.45 g/g d-glucose, 0.60 g/g d-xylose, and 0.61 g/g l-arabinose with 21.7 g/L ethanol, 20.2 g/L xylitol, and 30.3 g/l l-arabitol, respectively. The enzyme with l-arabitol dehydrogenase (LAD) activity was purified from the strain and found to exhibit broad specificity to polyols, such as xylitol, d-sorbitol, ribitol, and l-arabitol. Xylitol was the preferred substrate with K m =16.1 mM and k cat /K m =67.0 min -1 mM -1 , while l-arabitol was also a substrate for the enzyme with K m =31.1 mM and k cat /K m =6.5 min -1  mM -1 . Therefore, this enzyme from M. caribbica was named xylitol dehydrogenase (McXDH). McXDH had an optimum temperature and pH at 40°C and 9.5, respectively. The McXDH gene included a coding sequence of 1086 bp encoding a putative 362 amino acid protein of 39 kDa with an apparent homopentamer structure. Native McXDH and recombinant McXDH exhibited relative activities toward l-arabitol of approximately 20% that toward xylitol, suggesting the applicability of this enzyme with the functions of XDH and LAD to the development of pentose-fermenting Saccharomyces cerevisiae. Copyright © 2016 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

Concentration of eicosapentaenoic acid (EPA and docosahexaenoic acid (DHA of Asian catfish oil by urea complexation: optimization of reaction conditions

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Pornpisanu Thammapat

2016-04-01

Full Text Available Optimization of the concentrating conditions of eicosapentaenoic acid (EPA and docosahexaenoic acid (DHA extracted from Asian catfish oil was studied to obtain a maximum concentration. The crude fish oil was extracted from the belly flap and adipose tissue of Asian catfish, and the extracted oil was used as fresh crude oil. The EPA and DHA were concentrated by the urea complexation method. A hexagonal rotatable design was applied to examine the effects of crystallization temperature and urea-to-fatty acid ratio on the total content of EPA and DHA (Y1 and the liquid recovery yield (Y2 . The second order polynomial regression models for Y1 and Y2 were employed to generate the response surfaces. Under the optimum conditions of -20 °C and a urea-to-fatty acid ratio of 4 (w/w, the total concentration of EPA and DHA could be increased by up to 88%, while a liquid recovery yield of 26% was obtained.

The significance of fructose and MSG in affecting lipid and docosahexaenoic acid (DHA) production of Aurantiochytrium sp. SW1

Science.gov (United States)

Rahman, Shariffah Nurhidayah Syed Abdul; Kalil, Mohd Sahaid; Hamid, Aidil Abdul

2018-04-01

Optimization of fermentation medium for the production of docosahexaenoic acid (DHA) by Aurantiochytrium sp. SW1 was carried out. In this study, levels of fructose, monosodium glutamate (MSG) and sea salt were optimized for enhanced lipid and DHA production using response surface methodology (RSM). The design contains a total of 20 runs with 6 central points replication. Cultivation was carried out in 500 mL flasks containing 100 mL nitrogen limited medium at 30°C for 96h. Sequential model sum of squares (SS) revealed that the system was adequately represented by a quadratic model (p<0.0001). ANOVA results showed that fructose and MSG as a single factor has significant positive effect on the DHA content of SW1. The estimated optimal levels of the factors were 100 g/L fructose, 8 g/L MSG and 47% sea salt. Subsequent cultivation employing the suggested values confirmed that the predicted response values were experimentally achievable and reproducible, where 8.82 g/L DHA (51.34% g/g lipid) was achieved.

Decrease in the cytosolic NADP+-dependent isocitrate dehydrogenase activity through porcine sperm capacitation.

Science.gov (United States)

Katoh, Yuki; Tamba, Michiko; Matsuda, Manabu; Kikuchi, Kazuhiro; Okamura, Naomichi

2018-02-26

In order to understand the molecular mechanisms involved in the sperm capacitation, we have identified the proteins tyrosine-phosphorylated during the capacitation especially in conjunction with the regulation of the levels of reactive oxygen species (ROS) in sperm. In the present study, the effects of the tyrosine phosphorylation of cytosolic NADP + -dependent isocitrate dehydrogenase (IDPc) on its catalytic activity and on the levels of ROS in sperm have been studied. The tyrosine phosphorylated IDPc showed a significantly lowered enzymatic activity. The immunocytochemical analyses using the highly specific antisera against IDPc revealed that IDPc was mainly localized to the principal piece of the porcine sperm flagellum. As IDPc is one of the major NADPH regenerating enzymes in porcine sperm, it is strongly suggested that the decrease in IDPc activity is involved in the increased levels of ROS, which results in the induction of hyperactivated flagellar movement and capacitation. Copyright © 2018 Elsevier Inc. All rights reserved.

Mildly abnormal general movement quality in infants is associated with higher Mead acid and lower arachidonic acid and shows a U-shaped relation with the DHA/AA ratio.

Science.gov (United States)

van Goor, S A; Schaafsma, A; Erwich, J J H M; Dijck-Brouwer, D A J; Muskiet, F A J

2010-01-01

We showed that docosahexaenoic acid (DHA) supplementation during pregnancy and lactation was associated with more mildly abnormal (MA) general movements (GMs) in the infants. Since this finding was unexpected and inter-individual DHA intakes are highly variable, we explored the relationship between GM quality and erythrocyte DHA, arachidonic acid (AA), DHA/AA and Mead acid in 57 infants of this trial. MA GMs were inversely related to AA, associated with Mead acid, and associated with DHA/AA in a U-shaped manner. These relationships may indicate dependence of newborn AA status on synthesis from linoleic acid. This becomes restricted during the intrauterine period by abundant de novo synthesis of oleic and Mead acids from glucose, consistent with reduced insulin sensitivity during the third trimester. The descending part of the U-shaped relation between MA GMs and DHA/AA probably indicates DHA shortage next to AA shortage. The ascending part may reflect a different developmental trajectory that is not necessarily unfavorable. Copyright 2009 Elsevier Ltd. All rights reserved.

Exercise training induces similar elevations in the activity of oxoglutarate dehydrogenase and peak oxygen uptake in the human quadriceps muscle

DEFF Research Database (Denmark)

Blomstrand, Eva; Krustrup, Peter; Søndergaard, Hans

2011-01-01

During exercise involving a small muscle mass, peak oxygen uptake is thought to be limited by peripheral factors, such as the degree of oxygen extraction from the blood and/or mitochondrial oxidative capacity. Previously, the maximal activity of the Krebs cycle enzyme oxoglutarate dehydrogenase has...

Autodisplay of active sorbitol dehydrogenase (SDH) yields a whole cell biocatalyst for the synthesis of rare sugars.

Science.gov (United States)

Jose, Joachim; von Schwichow, Steffen

2004-04-02

Whole cell biocatalysts are attractive technological tools for the regio- and enantioselective synthesis of products, especially from substrates with several identical reactive groups. In the present study, a whole cell biocatalyst for the synthesis of rare sugars from polyalcohols was constructed. For this purpose, sorbitol dehydrogenase (SDH) from Rhodobacter sphaeroides, a member of the short-chain dehydrogenase/reductase (SDR) family, was expressed on the surface of Escherichia coli using Autodisplay. Autodisplay is an efficient surface display system for Gram-negative bacteria and is based on the autotransporter secretion pathway. Transport of SDH to the outer membrane was monitored by SDS-PAGE and Western blotting of different cell fractions. The surface exposure of the enzyme could be verified by immunofluorescence microscopy and fluorescence activated cell sorting (FACS). The activity of whole cells displaying SDH at the surface was determined in an optical test. Specific activities were found to be 12 mU per 3.3 x 10(8) cells for the conversion of D-glucitol (sorbitol) to D-fructose, 7 mU for the conversion D-galactitol to D-tagatose, and 17 mU for the conversion of L-arabitol to L-ribulose. The whole cell biocatalyst obtained by surface display of SDH could also produce D-glucitol from D-fructose (29 mU per 3.3 x 10(8) cells).

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

Science.gov (United States)

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 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

Gene expression of fatty acid transport and binding proteins in the blood-brain barrier and the cerebral cortex of the rat: differences across development and with different DHA brain status.

Science.gov (United States)

Pélerin, Hélène; Jouin, Mélanie; Lallemand, Marie-Sylvie; Alessandri, Jean-Marc; Cunnane, Stephen C; Langelier, Bénédicte; Guesnet, Philippe

2014-11-01

Specific mechanisms for maintaining docosahexaenoic acid (DHA) concentration in brain cells but also transporting DHA from the blood across the blood-brain barrier (BBB) are not agreed upon. Our main objective was therefore to evaluate the level of gene expression of fatty acid transport and fatty acid binding proteins in the cerebral cortex and at the BBB level during the perinatal period of active brain DHA accretion, at weaning, and until the adult age. We measured by real time RT-PCR the mRNA expression of different isoforms of fatty acid transport proteins (FATPs), long-chain acyl-CoA synthetases (ACSLs), fatty acid binding proteins (FABPs) and the fatty acid transporter (FAT)/CD36 in cerebral cortex and isolated microvessels at embryonic day 18 (E18) and postnatal days 14, 21 and 60 (P14, P21 and P60, respectively) in rats receiving different n-3 PUFA dietary supplies (control, totally deficient or DHA-supplemented). In control rats, all the genes were expressed at the BBB level (P14 to P60), the mRNA levels of FABP5 and ACSL3 having the highest values. Age-dependent differences included a systematic decrease in the mRNA expressions between P14-P21 and P60 (2 to 3-fold), with FABP7 mRNA abundance being the most affected (10-fold). In the cerebral cortex, mRNA levels varied differently since FATP4, ACSL3 and ACSL6 and the three FABPs genes were highly expressed. There were no significant differences in the expression of the 10 genes studied in n-3 deficient or DHA-supplemented rats despite significant differences in their brain DHA content, suggesting that brain DHA uptake from the blood does not necessarily require specific transporters within cerebral endothelial cells and could, under these experimental conditions, be a simple passive diffusion process. Copyright © 2014 Elsevier Ltd. All rights reserved.

Liver conversion of docosahexaenoic and arachidonic acids from their 18-carbon precursors in rats on a DHA-free but α-LNA-containing n-3 PUFA adequate diet.

Science.gov (United States)

Gao, Fei; Kim, Hyung-Wook; Igarashi, Miki; Kiesewetter, Dale; Chang, Lisa; Ma, Kaizong; Rapoport, Stanley I

2011-01-01

The long-chain polyunsaturated fatty acids (PUFAs), eicosapentaenoic acid (EPA, 20:5n-3), docosahexaenoic acid (DHA, 22:6n-3), and arachidonic acid (AA, 20:4n-6), are critical for health. These PUFAs can be synthesized in liver from their plant-derived precursors, α-linolenic acid (α-LNA, 18:3n-3) and linoleic acid (LA, 18:2n-6). Vegetarians and vegans may have suboptimal long-chain n-3 PUFA status, and the extent of the conversion of α-LNA to EPA and DHA by the liver is debatable. We quantified liver conversion of DHA and other n-3 PUFAs from α-LNA in rats fed a DHA-free but α-LNA (n-3 PUFA) adequate diet, and compared results to conversion of LA to AA. [U-(13)C]LA or [U-(13)C]α-LNA was infused intravenously for 2h at a constant rate into unanesthetized rats fed a DHA-free α-LNA adequate diet, and published equations were used to calculate kinetic parameters. The conversion coefficient k(⁎) of DHA from α-LNA was much higher than for AA from LA (97.2×10(-3) vs. 10.6×10(-3)min(-1)), suggesting that liver elongation-desaturation is more selective for n-3 PUFA biosynthesis on a per molecule basis. The net daily secretion rate of DHA, 20.3μmol/day, exceeded the reported brain DHA consumption rate by 50-fold, suggesting that the liver can maintain brain DHA metabolism with an adequate dietary supply solely of α-LNA. This infusion method could be used in vegetarians or vegans to determine minimal daily requirements of EPA and DHA in humans. Published by Elsevier B.V.

QSAR study on the antimalarial activity of Plasmodium falciparum dihydroorotate dehydrogenase (PfDHODH) inhibitors.

Science.gov (United States)

Hou, X; Chen, X; Zhang, M; Yan, A

2016-01-01

Plasmodium falciparum, the most fatal parasite that causes malaria, is responsible for over one million deaths per year. P. falciparum dihydroorotate dehydrogenase (PfDHODH) has been validated as a promising drug development target for antimalarial therapy since it catalyzes the rate-limiting step for DNA and RNA biosynthesis. In this study, we investigated the quantitative structure-activity relationships (QSAR) of the antimalarial activity of PfDHODH inhibitors by generating four computational models using a multilinear regression (MLR) and a support vector machine (SVM) based on a dataset of 255 PfDHODH inhibitors. All the models display good prediction quality with a leave-one-out q(2) >0.66, a correlation coefficient (r) >0.85 on both training sets and test sets, and a mean square error (MSE) antimalarial activity. The models are capable of predicting inhibitors' antimalarial activity and the molecular descriptors for building the models could be helpful in the development of new antimalarial drugs.

Inactivation of pyruvate dehydrogenase kinase 2 by mitochondrial reactive oxygen species.

Science.gov (United States)

Hurd, Thomas R; Collins, Yvonne; Abakumova, Irina; Chouchani, Edward T; Baranowski, Bartlomiej; Fearnley, Ian M; Prime, Tracy A; Murphy, Michael P; James, Andrew M

2012-10-12

Reactive oxygen species are byproducts of mitochondrial respiration and thus potential regulators of mitochondrial function. Pyruvate dehydrogenase kinase 2 (PDHK2) inhibits the pyruvate dehydrogenase complex, thereby regulating entry of carbohydrates into the tricarboxylic acid (TCA) cycle. Here we show that PDHK2 activity is inhibited by low levels of hydrogen peroxide (H(2)O(2)) generated by the respiratory chain. This occurs via reversible oxidation of cysteine residues 45 and 392 on PDHK2 and results in increased pyruvate dehydrogenase complex activity. H(2)O(2) derives from superoxide (O(2)(.)), and we show that conditions that inhibit PDHK2 also inactivate the TCA cycle enzyme, aconitase. These findings suggest that under conditions of high mitochondrial O(2)(.) production, such as may occur under nutrient excess and low ATP demand, the increase in O(2)() and H(2)O(2) may provide feedback signals to modulate mitochondrial metabolism.

Immunocapture and microplate-based activity and quantity measurement of pyruvate dehydrogenase in human peripheral blood mononuclear cells.

Science.gov (United States)

Liu, Xiaowen; Pervez, Hira; Andersen, Lars W; Uber, Amy; Montissol, Sophia; Patel, Parth; Donnino, Michael W

2015-01-01

Pyruvate dehydrogenase (PDH) activity is altered in many human disorders. Current methods require tissue samples and yield inconsistent results. We describe a modified method for measuring PDH activity from isolated human peripheral blood mononuclear cells (PBMCs). RESULTS/METHODOLOGY: We found that PDH activity and quantity can be successfully measured in human PBMCs. Freeze-thaw cycles cannot efficiently disrupt the mitochondrial membrane. Processing time of up to 20 h does not affect PDH activity with proteinase inhibitor addition and a detergent concentration of 3.3% showed maximum yield. Sample protein concentration is correlated to PDH activity and quantity in human PBMCs from healthy subjects. Measuring PDH activity from PBMCs is a novel, easy and less invasive way to further understand the role of PDH in human disease.

The Role of Pyruvate Dehydrogenase Kinase in Diabetes and Obesity

Directory of Open Access Journals (Sweden)

In-Kyu Lee

2014-06-01

Full Text Available The pyruvate dehydrogenase complex (PDC is an emerging target for the treatment of metabolic syndrome. To maintain a steady-state concentration of adenosine triphosphate during the feed-fast cycle, cells require efficient utilization of fatty acid and glucose, which is controlled by the PDC. The PDC converts pyruvate, coenzyme A (CoA, and oxidized nicotinamide adenine dinucleotide (NAD+ into acetyl-CoA, reduced form of nicotinamide adenine dinucleotide (NADH, and carbon dioxide. The activity of the PDC is up- and down-regulated by pyruvate dehydrogenase kinase and pyruvate dehydrogenase phosphatase, respectively. In addition, pyruvate is a key intermediate of glucose oxidation and an important precursor for the synthesis of glucose, glycerol, fatty acids, and nonessential amino acids.

Plant Formate Dehydrogenase

Energy Technology Data Exchange (ETDEWEB)

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.

Growth phase significantly decreases the DHA-to-EPA ratio in marine microalgae

NARCIS (Netherlands)

Boelen, Peter; Van Mastrigt, Audrey; Van De Bovenkamp, Henk H.; Heeres, Hero J.; Buma, Anita G. J.

Microalgae are the principal producers of long-chain polyunsaturated fatty acids (LC-PUFAs) such as eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) in marine ecosystems. Algae are used in aquaculture systems as direct or indirect feed for zooplankton, filter-feeding mollusks and larval

DHA-Containing Oilseed: A Timely Solution for the Sustainability Issues Surrounding Fish Oil Sources of the Health-Benefitting Long-Chain Omega-3 Oils

Directory of Open Access Journals (Sweden)

Soressa M. Kitessa

2014-05-01

Full Text Available Benefits of long-chain (≥C20 omega-3 oils (LC omega-3 oils for reduction of the risk of a range of disorders are well documented. The benefits result from eicosapentaenoic acid (EPA and docosahexaenoic acid (DHA; optimal intake levels of these bioactive fatty acids for maintenance of normal health and prevention of diseases have been developed and adopted by national and international health agencies and science bodies. These developments have led to increased consumer demand for LC omega-3 oils and, coupled with increasing global population, will impact on future sustainable supply of fish. Seafood supply from aquaculture has risen over the past decades and it relies on harvest of wild catch fisheries also for its fish oil needs. Alternate sources of LC omega-3 oils are being pursued, including genetically modified soybean rich in shorter-chain stearidonic acid (SDA, 18:4ω3. However, neither oils from traditional oilseeds such as linseed, nor the SDA soybean oil have shown efficient conversion to DHA. A recent breakthrough has seen the demonstration of a land plant-based oil enriched in DHA, and with omega-6 PUFA levels close to that occurring in marine sources of EPA and DHA. We review alternative sources of DHA supply with emphasis on the need for land plant oils containing EPA and DHA.

DHA-Containing Oilseed: A Timely Solution for the Sustainability Issues Surrounding Fish Oil Sources of the Health-Benefitting Long-Chain Omega-3 Oils

Science.gov (United States)

Kitessa, Soressa M.; Abeywardena, Mahinda; Wijesundera, Chakra; Nichols, Peter D.

2014-01-01

Benefits of long-chain (≥C20) omega-3 oils (LC omega-3 oils) for reduction of the risk of a range of disorders are well documented. The benefits result from eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA); optimal intake levels of these bioactive fatty acids for maintenance of normal health and prevention of diseases have been developed and adopted by national and international health agencies and science bodies. These developments have led to increased consumer demand for LC omega-3 oils and, coupled with increasing global population, will impact on future sustainable supply of fish. Seafood supply from aquaculture has risen over the past decades and it relies on harvest of wild catch fisheries also for its fish oil needs. Alternate sources of LC omega-3 oils are being pursued, including genetically modified soybean rich in shorter-chain stearidonic acid (SDA, 18:4ω3). However, neither oils from traditional oilseeds such as linseed, nor the SDA soybean oil have shown efficient conversion to DHA. A recent breakthrough has seen the demonstration of a land plant-based oil enriched in DHA, and with omega-6 PUFA levels close to that occurring in marine sources of EPA and DHA. We review alternative sources of DHA supply with emphasis on the need for land plant oils containing EPA and DHA. PMID:24858407

DHA-containing oilseed: a timely solution for the sustainability issues surrounding fish oil sources of the health-benefitting long-chain omega-3 oils.

Science.gov (United States)

Kitessa, Soressa M; Abeywardena, Mahinda; Wijesundera, Chakra; Nichols, Peter D

2014-05-22

Benefits of long-chain (≥C20) omega-3 oils (LC omega-3 oils) for reduction of the risk of a range of disorders are well documented. The benefits result from eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA); optimal intake levels of these bioactive fatty acids for maintenance of normal health and prevention of diseases have been developed and adopted by national and international health agencies and science bodies. These developments have led to increased consumer demand for LC omega-3 oils and, coupled with increasing global population, will impact on future sustainable supply of fish. Seafood supply from aquaculture has risen over the past decades and it relies on harvest of wild catch fisheries also for its fish oil needs. Alternate sources of LC omega-3 oils are being pursued, including genetically modified soybean rich in shorter-chain stearidonic acid (SDA, 18:4ω3). However, neither oils from traditional oilseeds such as linseed, nor the SDA soybean oil have shown efficient conversion to DHA. A recent breakthrough has seen the demonstration of a land plant-based oil enriched in DHA, and with omega-6 PUFA levels close to that occurring in marine sources of EPA and DHA. We review alternative sources of DHA supply with emphasis on the need for land plant oils containing EPA and DHA.

Effect of DHA and CoenzymeQ10 Against Aβ- and Zinc-Induced Mitochondrial Dysfunction in Human Neuronal Cells

Directory of Open Access Journals (Sweden)

Nadia Sadli

2013-07-01

Full Text Available Background: Beta-amyloid (Aβ protein is a key factor in the pathogenesis of Alzheimer's disease (AD and it has been reported that mitochondria is involved in the biochemical pathway by which Aβ can lead to neuronal dysfunction. Coenzyme Q10 (CoQ10 is an essential cofactor involved in the mitochondrial electron transport chain and has been suggested as a potential therapeutic agent in AD. Zinc toxicity also affects cellular energy production by decreasing oxygen consumption rate (OCR and ATP turnover in human neuronal cells, which can be restored by the neuroprotective effect of docosahexaenoic acid (DHA. Method: In the present study, using Seahorse XF-24 Metabolic Flux Analysis we investigated the effect of DHA and CoQ10 alone and in combination against Aβ- and zinc-mediated changes in the mitochondrial function of M17 neuroblastoma cell line. Results: Here, we observed that DHA is specifically neuroprotective against zinc-triggered mitochondrial dysfunction, but does not directly affect Aβ neurotoxicity. CoQ10 has shown to be protective against both Aβ- and zinc-induced alterations in mitochondrial function. Conclusion: Our results indicate that DHA and CoQ10 may be useful for the prevention, treatment and management of neurodegenerative diseases such as AD.

Lipid remodeling and an altered membrane-associated proteome may drive the differential effects of EPA and DHA treatment on skeletal muscle glucose uptake and protein accretion.

Science.gov (United States)

Jeromson, Stewart; Mackenzie, Ivor; Doherty, Mary K; Whitfield, Phillip D; Bell, Gordon; Dick, James; Shaw, Andy; Rao, Francesco V; Ashcroft, Stephen P; Philp, Andrew; Galloway, Stuart D R; Gallagher, Iain; Hamilton, D Lee

2018-06-01

In striated muscle, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) have differential effects on the metabolism of glucose and differential effects on the metabolism of protein. We have shown that, despite similar incorporation, treatment of C 2 C 12 myotubes (CM) with EPA but not DHA improves glucose uptake and protein accretion. We hypothesized that these differential effects of EPA and DHA may be due to divergent shifts in lipidomic profiles leading to altered proteomic profiles. We therefore carried out an assessment of the impact of treating CM with EPA and DHA on lipidomic and proteomic profiles. Fatty acid methyl esters (FAME) analysis revealed that both EPA and DHA led to similar but substantials changes in fatty acid profiles with the exception of arachidonic acid, which was decreased only by DHA, and docosapentanoic acid (DPA), which was increased only by EPA treatment. Global lipidomic analysis showed that EPA and DHA induced large alterations in the cellular lipid profiles and in particular, the phospholipid classes. Subsequent targeted analysis confirmed that the most differentially regulated species were phosphatidylcholines and phosphatidylethanolamines containing long-chain fatty acids with five (EPA treatment) or six (DHA treatment) double bonds. As these are typically membrane-associated lipid species we hypothesized that these treatments differentially altered the membrane-associated proteome. Stable isotope labeling by amino acids in cell culture (SILAC)-based proteomics of the membrane fraction revealed significant divergence in the effects of EPA and DHA on the membrane-associated proteome. We conclude that the EPA-specific increase in polyunsaturated long-chain fatty acids in the phospholipid fraction is associated with an altered membrane-associated proteome and these may be critical events in the metabolic remodeling induced by EPA treatment.

Modulation of NADP(+)-dependent isocitrate dehydrogenase in aging.

Science.gov (United States)

Kil, In Sup; Lee, Young Sup; Bae, Young Seuk; Huh, Tae Lin; Park, Jeen-Woo

2004-01-01

NADPH is an important cofactor in many biosynthesis pathways and the regeneration of reduced glutathione, critically important in cellular defense against oxidative damage. It is mainly produced by glucose-6-phosphate dehydrogenase, malic enzyme, and NADP(+)-specific isocitrate dehydrogenases (ICDHs). Here, we investigated age-related changes in ICDH activity and protein expression in IMR-90 human diploid fibroblast cells and tissues from Fischer 344 rats. We found that in IMR-90 cells the activity of cytosolic ICDH (IDPc) gradually increased with age up to the 46-48 population doubling level (PDL) and then gradually decreased at later PDL. 2',7'-Dichloro-fluorescein fluorescence which reflects intracellular ROS generation was increased with aging in IMR-90 cells. In ad libitum-fed rats, we noted age-related, tissue-specific modulations of IDPc and mitochondrial ICDH (IDPm) activities and protein expression in the liver, kidney and testes. In contrast, ICDH activities and protein expression were not significantly modulated in diet-restricted rats. These data suggest that modulation of ICDH is an age-dependent and a tissue-specific phenomenon.

Omega-3 polyunsaturated fatty acid blood biomarkers increase linearly in men and women after tightly controlled intakes of 0.25, 0.5, and 1 g/d of EPA + DHA.

Science.gov (United States)

Patterson, Ashley C; Chalil, Alan; Aristizabal Henao, Juan J; Streit, Isaac T; Stark, Ken D

2015-12-01

Blood levels of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) have been related to coronary heart disease risk. Understanding the response of EPA + DHA in blood to dietary intake of EPA + DHA would facilitate the use of blood measures as markers of adherence and enable the development of dietary recommendations. The objective of this study is examine the blood response to intakes of EPA + DHA ≤1 g/d with an intervention designed for dietary adherence. It was hypothesized this relationship would be linear and that intakes of EPA + DHA DHA intake of men and women (n = 20) was determined by food frequency questionnaire and adherence was monitored by weekly fingertip blood sampling for fatty acid determinations. Participants consumed nutraceuticals to achieve intakes of 0.25 g/d and 0.5 g/d EPA + DHA for successive four-week periods. A subgroup (n = 5) had intakes of 1.0 g/d EPA + DHA for an additional 4 weeks. Fatty acid composition of whole blood, erythrocytes, and plasma phospholipids were determined at each time point. Blood levels of EPA and DHA increased linearly in these pools. A comprehensive review of the literature was used to verify the blood-intake relationship. Blood levels of long chain omega-3 polyunsaturated fatty acids reached blood levels associated with the highest levels of primary cardiac arrest reduction and sudden cardiac death risk only with intakes of 1.0 g/d of EPA + DHA. The blood biomarker response to intakes of EPA + DHA ≤1 g/d is linear in a small but highly adherent study sample and this information can assist in determining adherence in clinical studies and help identify dietary intake targets from associations between blood and disease. Copyright © 2015 Elsevier Inc. All rights reserved.

Maternal and fetal brain contents of docosahexaenoic acid (DHA) and arachidonic acid (AA) at various essential fatty acid (EFA), DHA and AA dietary intakes during pregnancy in mice

NARCIS (Netherlands)

van Goor, Saskia A; Dijck-Brouwer, D A Janneke; Fokkema, M Rebecca; van der Iest, Theo Hans; Muskiet, Frits A J

We investigated essential fatty acids (EFA) and long-chain polyunsaturated fatty acids (LCP) in maternal and fetal brain as a function of EFA/LCP availability to the feto-maternal unit in mice. Diets varying in parent EFA, arachidonic acid (AA), and docosahexaenoic acid (DHA) were administered from

Mathematical modeling of fed-batch fermentation of Schizochytrium sp. FJU-512 growth and DHA production using a shift control strategy.

Science.gov (United States)

Zhang, Mingliang; Wu, Weibin; Guo, Xiaolei; Weichen, You; Qi, Feng; Jiang, Xianzhang; Huang, Jianzhong

2018-03-01

To obtain high-cell-density cultures of Schizochytrium sp. FJU-512 for DHA production, two stages of fermentation strategy were used and carbon/nitrogen ratio, DO and temperature were controlled at different levels. The final dry cell weight, total lipid production and DHA yield in 15 l bioreactor reached 103.9, 37.2 and 16.0 g/l, respectively. For the further study of microbial growth and DHA production dynamics, we established a set of kinetic models for the fed-batch production of DHA by Schizochytrium sp. FJU-512 in 15 and 100 l fermenters and a compensatory parameter n was integrated into the model in order to find the optimal mathematical equations. A modified Logistic model was proposed to fit the cell growth data and the following kinetic parameters were obtained: µ m  = 0.0525/h, X m  = 100 g/l and n  = 4.1717 for the 15 l bioreactor, as well as µ m  = 0.0382/h, X m  = 107.4371 g/l and n  = 10 for the 100 l bioreactor. The Luedeking-Piret equations were utilized to model DHA production, yielding values of α  = 0.0648 g/g and β  = 0.0014 g/g/h for the 15 l bioreactor, while the values of α and β obtained for the 100 l fermentation were 0.0209 g/g and 0.0030 g/g/h. The predicted results compared with experimental data showed that the established models had a good fitting precision and were able to exactly depict the dynamic features of the DHA production process.

Lipid profiling following intake of the omega 3 fatty acid DHA identifies the peroxidized metabolites F4-neuroprostanes as the best predictors of atherosclerosis prevention.

Science.gov (United States)

Gladine, Cécile; Newman, John W; Durand, Thierry; Pedersen, Theresa L; Galano, Jean-Marie; Demougeot, Céline; Berdeaux, Olivier; Pujos-Guillot, Estelle; Mazur, Andrzej; Comte, Blandine

2014-01-01

The anti-atherogenic effects of omega 3 fatty acids, namely eicosapentaenoic (EPA) and docosahexaenoic acids (DHA) are well recognized but the impact of dietary intake on bioactive lipid mediator profiles remains unclear. Such a profiling effort may offer novel targets for future studies into the mechanism of action of omega 3 fatty acids. The present study aimed to determine the impact of DHA supplementation on the profiles of polyunsaturated fatty acids (PUFA) oxygenated metabolites and to investigate their contribution to atherosclerosis prevention. A special emphasis was given to the non-enzymatic metabolites knowing the high susceptibility of DHA to free radical-mediated peroxidation and the increased oxidative stress associated with plaque formation. Atherosclerosis prone mice (LDLR(-/-)) received increasing doses of DHA (0, 0.1, 1 or 2% of energy) during 20 weeks leading to a dose-dependent reduction of atherosclerosis (R(2) = 0.97, p = 0.02), triglyceridemia (R(2) = 0.97, p = 0.01) and cholesterolemia (R(2) = 0.96, pF4-neuroprostanes, a specific class of DHA peroxidized metabolites, was strongly correlated with the hepatic DHA level. Moreover, unbiased statistical analysis including correlation analyses, hierarchical cluster and projection to latent structure discriminate analysis revealed that the hepatic level of F4-neuroprostanes was the variable most negatively correlated with the plaque extent (pF4-neuroprostanes in particular, are potential biomarkers of DHA-associated atherosclerosis prevention. While these may contribute to the anti-atherogenic effects of DHA, further in vitro investigations are needed to confirm such a contention and to decipher the molecular mechanisms of action.

Dietary Intakes of EPA and DHA Omega-3 Fatty Acids among US Childbearing-Age and Pregnant Women: An Analysis of NHANES 2001-2014.

Science.gov (United States)

Zhang, Zhiying; Fulgoni, Victor L; Kris-Etherton, Penny M; Mitmesser, Susan Hazels

2018-03-28

The 2015–2020 Dietary Guidelines for Americans (DGA) recommend that the general population should consume about 8 ounces (oz.) per week of a variety of seafood, providing approximately 250 mg per day of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), and that pregnant and lactating women should consume 8–12 oz. per week of seafood. We determined the usual intakes, percentage not meeting recommendations, and trends in EPA and DHA intakes among childbearing-age and pregnant women (15–44 years of age) using the NHANES cycles 2001–2002 through 2013–2014. For the childbearing-age women, the mean usual intake of seafood was 0.44 ± 0.02 oz. equivalent per day and 100% of the population was below the DGA recommendation. Mean usual intakes of EPA, DHA, and combined EPA and DHA from foods and dietary supplements combined were 26.8 ± 1.4, 62.2 ± 1.9, and 88.1 ± 3.0 mg per day, respectively. Over 95% of the sample did not meet the daily intakes of 250 mg EPA and DHA. Similar results were observed for pregnant women. After controlling for covariates, there were slight but significant increases in EPA and DHA intakes from foods and dietary supplements over the 14-year span among childbearing-age ( p = 0.005) and pregnant women ( p = 0.002). It was estimated that a majority of U.S. childbearing-age and pregnant women consumed significantly lower amounts of seafood than what the DGA recommends, which subsequently leads to low intakes of EPA and DHA; in addition, dietary supplement use has not eliminated the nutrient shortfall.

Rapid synthesis of triazine inhibitors of inosine monophosphate dehydrogenase.

Science.gov (United States)

Pitts, William J; Guo, Junqing; Dhar, T G Murali; Shen, Zhongqi; Gu, Henry H; Watterson, Scott H; Bednarz, Mark S; Chen, Bang Chi; Barrish, Joel C; Bassolino, Donna; Cheney, Daniel; Fleener, Catherine A; Rouleau, Katherine A; Hollenbaugh, Diane L; Iwanowicz, Edwin J

2002-08-19

A series of novel triazine-based small molecule inhibitors (IV) of inosine monophosphate dehydrogenase was prepared. The synthesis and the structure-activity relationships (SAR) derived from in vitro studies are described.

Novel amide-based inhibitors of inosine 5'-monophosphate dehydrogenase.

Science.gov (United States)

Watterson, Scott H; Liu, Chunjian; Dhar, T G Murali; Gu, Henry H; Pitts, William J; Barrish, Joel C; Fleener, Catherine A; Rouleau, Katherine; Sherbina, N Z; Hollenbaugh, Diane L; Iwanowicz, Edwin J

2002-10-21

A series of novel amide-based small molecule inhibitors of inosine monophosphate dehydrogenase (IMPDH) was explored. The synthesis and the structure-activity relationships (SARs) derived from in vitro studies are described.

Level of coenzyme A and the activity of certain dehydrogenases under chronic low dose X-irradiation

Energy Technology Data Exchange (ETDEWEB)

Cherkasova, L A; Novik, V A; Tsychun, G F [AN Belorusskoj SSR, Minsk. Inst. Fiziologii

1975-01-01

A study was made of the effect of long-term x ray irradiation (cumulative dose 50 R) on: the content of co-enzyme A (KoA) in the brain and liver, the activity of a number of oxydizing reducing enzymes in the brain mitochondria and heart muscle, and the blood glucocorticoid content. It was established that the metabolism of brain and liver KoA is quite stable, the enzymes of the brain tricarbonic acids and pyruvate-dehydrogenase cycle are labile.

Role of β-catenin signaling in the anti-invasive effect of the omega-3 fatty acid DHA in human melanoma cells.

Science.gov (United States)

Serini, Simona; Zinzi, Antonio; Ottes Vasconcelos, Renata; Fasano, Elena; Riillo, Maria Greca; Celleno, Leonardo; Trombino, Sonia; Cassano, Roberta; Calviello, Gabriella

2016-11-01

We previously found that docosahexaenoic acid (DHA), a dietary polyunsaturated fatty acid present at high level in fatty fish, inhibited cell growth and induced differentiation of melanoma cells in vitro by increasing nuclear β-catenin content. An anti-neoplastic role of nuclear β-catenin was suggested in melanoma, and related to the presence in the melanocyte lineage of the microphtalmia transcription factor (MITF), which interferes with the transcription of β-catenin/TCF/LEF pro-invasive target genes. In the present work we investigated if DHA could inhibit the invasive potential of melanoma cells, and if this effect could be related to DHA-induced alterations of the Wnt/β-catenin signaling, including changes in MITF expression. WM115 and WM266-4 human melanoma, and B16-F10 murine melanoma cell lines were used. Cell invasion was evaluated by Wound Healing and Matrigel transwell assays. Protein expression was analyzed by Western Blotting and β-catenin phosphorylation by immunoprecipitation. The role of MITF in the anti-invasive effect of DHA was analyzed by siRNA gene silencing. We found that DHA inhibited anchorage-independent cell growth, reduced their migration/invasion in vitro and down-regulated several Matrix Metalloproteinases (MMP: MMP-2, MT1-MMP and MMP-13), known to be involved in melanoma invasion. We related these effects to the β-catenin increased nuclear expression and PKA-dependent phosphorylation, as well as to the increased expression of MITF. The data obtained further support the potential role of dietary DHA as suppressor of melanoma progression to invasive malignancy through its ability to enhance MITF expression and PKA-dependent nuclear β-catenin phosphorylation. Copyright © 2016. Published by Elsevier Ireland Ltd.

Effects of dietary supplementation with docosahexaenoic acid (DHA on hippocampal gene expression in streptozotocin induced diabetic C57Bl/6 mice

Directory of Open Access Journals (Sweden)

Jency Thomas

2015-08-01

Full Text Available A body of evidence has accumulated indicating diabetes is associated with cognitive impairments. Effective strategies are therefore needed that will delay or prevent the onset of these diabetes-related deficits. In this regard, dietary modification with the naturally occurring compound, docosahexaenoic acid (DHA, holds significant promise as it has been shown to have anti-inflammatory, anti-oxidant, and anti-apoptotic properties. The hippocampus, a limbic structure involved in cognitive functions such as memory formation, is particularly vulnerable to the neurotoxic effects related to diabetes, and we have previously shown that streptozotocin-induced diabetes alters hippocampal gene expression, including genes involved in synaptic plasticity and neurogenesis. In the present study, we explored the effects of dietary supplementation with DHA on hippocampal gene expression in C57Bl/6 diabetic mice. Diabetes was established using streptozotocin (STZ and once stable, the dietary intervention group received AIN93G diet supplemented with DHA (50 mg/kg/day for 6 weeks. Microarray based genome-wide expression analysis was carried out on the hippocampus of DHA supplemented diabetic mice and confirmed by real time polymerase chain reaction (RT-qPCR. Genome-wide analysis identified 353 differentially expressed genes compared to non-supplemented diabetic mice. For example, six weeks of dietary DHA supplementation resulted in increased hippocampal expression of Igf II and Sirt1 and decreased expression of Tnf-α, Il6, Mapkapk2 and ApoE, compared to non-supplemented diabetic mice. Overall, DHA supplementation appears to alter hippocampal gene expression in a way that is consistent with it being neuroprotective in the context of the metabolic and inflammatory insults associated with diabetes.

Stability and activity of lactate dehydrogenase on biofunctional layers deposited by activated vapor silanization (AVS) and immersion silanization (IS)

Science.gov (United States)

Calvo, Jorge Nieto-Márquez; Elices, Manuel; Guinea, Gustavo V.; Pérez-Rigueiro, José; Arroyo-Hernández, María

2017-09-01

The interaction between surfaces and biological elements, in particular, proteins is critical for the performance of biomaterials and biosensors. This interaction can be controlled by modifying the surface in a process known as biofunctionalization. In this work, the enzyme lactate dehydrogenase (LDH) is used to study the stability of the interaction between a functional protein and amine-functionalized surfaces. Two different functionalization procedures were compared: Activated Vapor Silanization (AVS) and Immersion Silanization (IS). Adsorption kinetics is shown to follow the Langmuir model for AVS-functionalized samples, while IS-functionalized samples show a certain instability if immersed in an aqueous medium for several hours. In turn, the enzymatic activity of LDH is preserved for longer times by using glutaraldehyde as crosslinker between the AVS biofunctional surface and the enzyme.

Forskolin- and dihydroalprenolol (DHA) binding sites and adenylate cyclase activity in heart of rats fed diets containing different oils

International Nuclear Information System (INIS)

Alam, S.Q.; Ren, Y.F.; Alam, B.S.

1987-01-01

The purpose of the present investigation was to determine if dietary lipids can induce changes in the adenylate cyclase system in rat heart. Three groups of male young Sprague-Dawley rats were fed for 6 weeks diets containing 10% corn oil (I), 8% coconut oil + 2% corn oil (II) or 10% menhaden oil (III). Adenylate cyclase activity (basal, fluoride-, isoproterenol-, and forskolin-stimulated) was higher in heart homogenates of rats in group III than in the other two groups. Concentration of the [ 3 H]-forskolin binding sites in the cardiac membranes were significantly higher in rats fed menhaden oil. The values (pmol/mg protein) were 4.8 +/- 0.2 (I), 4.5 +/- 0.7 (II) and 8.4 +/- 0.5 (III). There was no significant difference in the affinity of the forskolin binding sites among the 3 dietary groups. When measured at different concentrations of forskolin, the adenylate cyclase activity in cardiac membranes of rats fed menhaden oil was higher than in the other 2 groups. Concentrations of the [ 3 H]DHA binding sites were slightly higher but their affinity was lower in cardiac membranes of rats fed menhaden oil. The results suggest that diets containing fish oil increase the concentration of the forskolin binding sites and may also affect the characteristics of the β-adrenergic receptor in rat heart

Mechanisms of activation of muscle branched-chain alpha-keto acid dehydrogenase during exercise in man

DEFF Research Database (Denmark)

Van Hall, Gerrit; MacLean, D A; Saltin, B

1996-01-01

1. Exercise leads to activation (dephosphorylation) of the branched-chain alpha-keto acid dehydrogenase (BCKADH). Here we investigate the effect of low pre-exercise muscle glycogen content and of branched-chain amino acid (BCAA) ingestion on the activity of BCKADH at rest and after 90 min of one......-leg knee-extensor exercise at 65% maximal one-leg power output in five subjects. 2. Pre-exercise BCAA ingestion (308 mg BCAAs (kg body wt)-1) caused an increased muscle BCAA uptake, a higher intramuscular BCAA concentration and activation of BCKADH both at rest (9 +/- 1 versus 25 +/- 5% for the control...... and BCAA test, respectively) and after exercise (27 +/- 4 versus 54 +/- 7%). 3. At rest the percentage active BCKADH was not different, 6 +/- 2% versus 5 +/- 1%, in the normal and low glycogen content leg (392 +/- 21 and 147 +/- 34 mumol glycosyl units (g dry muscle)-1, respectively). The post...

Immunocapture and microplate-based activity and quantity measurement of pyruvate dehydrogenase in human peripheral blood mononuclear cells

Science.gov (United States)

Liu, Xiaowen; Pervez, Hira; Andersen, Lars W; Uber, Amy; Montissol, Sophia; Patel, Parth; Donnino, Michael W

2015-01-01

Background Pyruvate dehydrogenase (PDH) activity is altered in many human disorders. Current methods require tissue samples and yield inconsistent results. We describe a modified method for measuring PDH activity from isolated human peripheral blood mononuclear cells (PBMCs). Results/Methodology We found that PDH activity and quantity can be successfully measured in human PBMCs. Freeze-thaw cycles cannot efficiently disrupt the mitochondrial membrane. Processing time of up to 20 h does not affect PDH activity with proteinase inhibitor addition and a detergent concentration of 3.3% showed maximum yield. Sample protein concentration is correlated to PDH activity and quantity in human PBMCs from healthy subjects. Conclusion Measuring PDH activity from PBMCs is a novel, easy and less invasive way to further understand the role of PDH in human disease. PMID:25826140

Homology modelling and docking analysis of L-lactate dehydrogenase from Streptococcus thermopilus

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Vukić Vladimir R.

2016-01-01

Full Text Available The aim of this research was to create a three-dimensional model of L-lactate dehydrogenase from the main yoghurt starter culture - Streptococcus thermopilus, to analyse its structural features and investigate substrate binding in the active site. NCBI BlastP was used against the Protein Data Bank database in order to identify the template for construction of homology models. Multiple sequence alignment was performed using the program MUSCULE within the UGENE 1.11.3 program. Homology models were constructed using the program Modeller v. 9.17. The obtained 3D model was verified by Ramachandran plots. Molecular docking simulations were performed using the program Surflex-Dock. The highest sequence similarity was observed with L-lactate dehydrogenase from Lactobacillus casei subsp. casei, with 69% identity. Therefore, its structure (PDB ID: 2ZQY:A was selected as a modelling template for homology modelling. Active residues are by sequence similarity predicted: S. thermophilus - HIS181 and S. aureus - HIS179. Binding energy of pyruvate to L-lactate dehydrogenase of S. thermopilus was - 7.874 kcal/mol. Pyruvate in L-lactate dehydrogenase of S. thermopilus makes H bonds with catalytic HIS181 (1.9 Å, as well as with THR235 (3.6 Å. Although our results indicate similar position of substrates between L-lactate dehydrogenase of S. thermopilus and S. aureus, differences in substrate distances and binding energy values could influence the reaction rate. Based on these results, the L-lactate dehydrogenase model proposed here could be used as a guide for further research, such as transition states of the reaction through molecular dynamics. [Projekat Ministarstva nauke Republike Srbije, br. III 46009

Determinants of DHA status and functional effects on metabolic markers and immune modulation in early life

DEFF Research Database (Denmark)

Harsløf, Laurine Bente Schram

Optimal intake of n-3 long chain polyunsaturated fatty acids (LCPUFA) during infancy and early childhood is not known and only a few studies have examined to what extend docosahexaenoic acid (DHA) status is affected by endogenous synthesis from α-linolenic acid relative to the influence of dietary...... intake and other potential determinants in infancy and childhood. The first part of the PhD thesis describes several potential determinants of infant and young child DHA status including genetic variation in FADS, breastfeeding and fish intake. Results can be found in Paper 1. Evidence for effects of n-3...

High energy electron beam inactivation of lactate dehydrogenase suspended in different aqueous media

International Nuclear Information System (INIS)

Hategan, A.; Oproiu, C.; Popescu, A.; Hategan, D.; Morariu, V.V.

1998-01-01

The direct and indirect effects of 5 MeV electron beam irradiation at various low temperatures, as well as the influence of the presence or absence of deuterium ions in the suspending medium of the enzyme, on the global enzymatic activity of lactate dehydrogenase have been studied. Frozen lactate dehydrogenase suspensions at 0 degC, -3 degC and -196 degC temperatures have been irradiated with the 5 MeV electron beam of a linear accelerator in the dose range 0-400 Gy. Liquid lactate dehydrogenase suspensions in D 2 O (99.98 %) and ultrapure water (17 ppm) at 0 degC have been irradiated in the dose range 0 -15 Gy. An exponential decrease was found in the enzymatic activity of irradiated lactate dehydrogenase, at all irradiation temperatures. The drastic decrease in the activity for the enzyme irradiated at 0 degC (total inhibition for a final dose of 100 Gy) indicate that at this temperature the indirect effects of radiation (due to the water radicals induced by radiation in the samples) are predominant. At -3 degC irradiation temperature the indirect effects of radiation are smaller but still present (a total decrease in the enzymatic activity for a dose of 250 Gy), while at -196 degC they are orders of magnitude reduced and the decrease in the enzymatic activity is due almost to the direct interaction of electrons with the macromolecules (70 % for a dose of 400 Gy)

The Pattern of Fatty Acids Displaced by EPA and DHA Following 12 Months Supplementation Varies between Blood Cell and Plasma Fractions

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Celia G. Walker

2015-08-01

Full Text Available Eicosapentaenoic acid (EPA and docosahexaenoic acid (DHA are increased in plasma lipids and blood cell membranes in response to supplementation. Whilst arachidonic acid (AA is correspondingly decreased, the effect on other fatty acids (FA is less well described and there may be site-specific differences. In response to 12 months EPA + DHA supplementation in doses equivalent to 0–4 portions of oily fish/week (1 portion: 3.27 g EPA+DHA multinomial regression analysis was used to identify important FA changes for plasma phosphatidylcholine (PC, cholesteryl ester (CE and triglyceride (TAG and for blood mononuclear cells (MNC, red blood cells (RBC and platelets (PLAT. Dose-dependent increases in EPA + DHA were matched by decreases in several n-6 polyunsaturated fatty acids (PUFA in PC, CE, RBC and PLAT, but were predominantly compensated for by oleic acid in TAG. Changes were observed for all FA classes in MNC. Consequently the n-6:n-3 PUFA ratio was reduced in a dose-dependent manner in all pools after 12 months (37%–64% of placebo in the four portions group. We conclude that the profile of the FA decreased in exchange for the increase in EPA + DHA following supplementation differs by FA pool with implications for understanding the impact of n-3 PUFA on blood lipid and blood cell biology.

The Pattern of Fatty Acids Displaced by EPA and DHA Following 12 Months Supplementation Varies between Blood Cell and Plasma Fractions.

Science.gov (United States)

Walker, Celia G; West, Annette L; Browning, Lucy M; Madden, Jackie; Gambell, Joanna M; Jebb, Susan A; Calder, Philip C

2015-08-03

Eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) are increased in plasma lipids and blood cell membranes in response to supplementation. Whilst arachidonic acid (AA) is correspondingly decreased, the effect on other fatty acids (FA) is less well described and there may be site-specific differences. In response to 12 months EPA + DHA supplementation in doses equivalent to 0-4 portions of oily fish/week (1 portion: 3.27 g EPA+DHA) multinomial regression analysis was used to identify important FA changes for plasma phosphatidylcholine (PC), cholesteryl ester (CE) and triglyceride (TAG) and for blood mononuclear cells (MNC), red blood cells (RBC) and platelets (PLAT). Dose-dependent increases in EPA + DHA were matched by decreases in several n-6 polyunsaturated fatty acids (PUFA) in PC, CE, RBC and PLAT, but were predominantly compensated for by oleic acid in TAG. Changes were observed for all FA classes in MNC. Consequently the n-6:n-3 PUFA ratio was reduced in a dose-dependent manner in all pools after 12 months (37%-64% of placebo in the four portions group). We conclude that the profile of the FA decreased in exchange for the increase in EPA + DHA following supplementation differs by FA pool with implications for understanding the impact of n-3 PUFA on blood lipid and blood cell biology.

High-throughput screening for cellobiose dehydrogenases by Prussian Blue in situ formation.

Science.gov (United States)

Vasilchenko, Liliya G; Ludwig, Roland; Yershevich, Olga P; Haltrich, Dietmar; Rabinovich, Mikhail L

2012-07-01

Extracellular fungal flavocytochrome cellobiose dehydrogenase (CDH) is a promising enzyme for both bioelectronics and lignocellulose bioconversion. A selective high-throughput screening assay for CDH in the presence of various fungal oxidoreductases was developed. It is based on Prussian Blue (PB) in situ formation in the presence of cellobiose (<0.25 mM), ferric acetate, and ferricyanide. CDH induces PB formation via both reduction of ferricyanide to ferrocyanide reacting with an excess of Fe³⁺ (pathway 1) and reduction of ferric ions to Fe²⁺ reacting with the excess of ferricyanide (pathway 2). Basidiomycetous and ascomycetous CDH formed PB optimally at pH 3.5 and 4.5, respectively. In contrast to the holoenzyme CDH, its FAD-containing dehydrogenase domain lacking the cytochrome domain formed PB only via pathway 1 and was less active than the parent enzyme. The assay can be applied on active growing cultures on agar plates or on fungal culture supernatants in 96-well plates under aerobic conditions. Neither other carbohydrate oxidoreductases (pyranose dehydrogenase, FAD-dependent glucose dehydrogenase, glucose oxidase) nor laccase interfered with CDH activity in this assay. Applicability of the developed assay for the selection of new ascomycetous CDH producers as well as possibility of the controlled synthesis of new PB nanocomposites by CDH are discussed. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

A high effective NADH-ferricyanide dehydrogenase coupled with laccase for NAD(+) regeneration.

Science.gov (United States)

Wang, Jizhong; Yang, Chengli; Chen, Xing; Bao, Bingxin; Zhang, Xuan; Li, Dali; Du, Xingfan; Shi, Ruofu; Yang, Junfang; Zhu, Ronghui

2016-08-01

To find an efficient and cheap system for NAD(+) regeneration A NADH-ferricyanide dehydrogenase was obtained from an isolate of Escherichia coli. Optimal activity of the NADH dehydrogenase was at 45 °C and pH 7.5, with a K m value for NADH of 10 μM. By combining the NADH dehydrogenase, potassium ferricyanide and laccase, a bi-enzyme system for NAD(+) regeneration was established. The system is attractive in that the O2 consumed by laccase is from air and the sole byproduct of the reaction is water. During the reaction process, 10 mM NAD(+) was transformed from NADH in less than 2 h under the condition of 0.5 U NADH dehydrogenase, 0.5 U laccase, 0.1 mM potassium ferricyanide at pH 5.6, 30 °C CONCLUSION: The bi-enzyme system employed the NADH-ferricyanide dehydrogenase and laccase as catalysts, and potassium ferricyanide as redox mediator, is a promising alternative for NAD(+) regeneration.

Arachidonic acid and DHA status in pregnant women is not associated with cognitive performance of their children at 4 or 6-7 years.

Science.gov (United States)

Crozier, Sarah R; Sibbons, Charlene M; Fisk, Helena L; Godfrey, Keith M; Calder, Philip C; Gale, Catharine R; Robinson, Sian M; Inskip, Hazel M; Baird, Janis; Harvey, Nicholas C; Cooper, Cyrus; Burdge, Graham C

2018-06-01

Arachidonic acid (ARA) and DHA, supplied primarily from the mother, are required for early development of the central nervous system. Thus, variations in maternal ARA or DHA status may modify neurocognitive development. We investigated the relationship between maternal ARA and DHA status in early (11·7 weeks) or late (34·5 weeks) pregnancy on neurocognitive function at the age of 4 years or 6-7 years in 724 mother-child pairs from the Southampton Women's Survey cohort. Plasma phosphatidylcholine fatty acid composition was measured in early and late pregnancy. ARA concentration in early pregnancy predicted 13 % of the variation in ARA concentration in late pregnancy (β=0·36, PDHA concentration in early pregnancy predicted 21 % of the variation in DHA concentration in late pregnancy (β=0·46, PDHA nor ARA concentrations in early or late pregnancy were associated significantly with neurocognitive function in children at the age of 4 years or the age of 6-7 years. These findings suggest that ARA and DHA status during pregnancy in the range found in this cohort are unlikely to have major influences on neurocognitive function in healthy children.

A Study of the Differential Effects of Eicosapentaenoic Acid (EPA) and Docosahexaenoic Acid (DHA) on Gene Expression Profiles of Stimulated Thp-1 Macrophages.

Science.gov (United States)

Allam-Ndoul, Bénédicte; Guénard, Frédéric; Barbier, Olivier; Vohl, Marie-Claude

2017-04-25

Background: An appropriate intake of omega-3 ( n -3) fatty acids (FAs) such as eicosapentaenoic and docosahexaenoic acid (EPA/DHA) from marine sources is known to have anti-inflammatory effects. However, molecular mechanisms underlying their beneficial effects on health are not fully understood. The aim of the present study was to characterize gene expression profiles of THP-1 macrophages, incubated in either EPA or DHA and stimulated with lipopolysaccharide (LPS), a pro-inflammatory agent. Methods: THP-1 macrophages were incubated into 10, 50 and 75 µM of EPA or DHA for 24 h, and 100 nM of LPS was added to the culture media for 18 h. Total mRNA was extracted and gene expression examined by microarray analysis using Illumina Human HT-12 expression beadchips (Illumina). Results: Pathway analysis revealed that EPA and DHA regulate genes involved in cell cycle regulation, apoptosis, immune response and inflammation, oxidative stress and cancer pathways in a differential and dose-dependent manner. Conclusions: EPA and DHA appear to exert differential effects on gene expression in THP-1 macrophages. Specific effects of n -3 FAs on gene expression levels are also dose-dependent.

Effect of Docosahexaenoic Acid Ingestion on Temporal Change in Urinary Excretion of Mercapturic Acid in ODS Rats.

Science.gov (United States)

Sekine, Seiji; Kubo, Kazuhiro; Tadokoro, Tadahiro; Saito, Morio

2007-11-01

We hypothesized a suppressive mechanism for docosahexaenoic acid (22:6n-3; DHA)-induced tissue lipid peroxidation in which the degradation products, especially aldehydic compounds, are conjugated with glutathione through catalysis by glutathione S-transferases, and then excreted into urine as mercapturic acids. In the present study, ascorbic acid-requiring ODS rats were fed a diet containing DHA (3.6% of total energy) for 31 days. Lipid peroxides including degradation products and their scavengers in the liver and kidney were determined, and the temporal change in the urinary excretion of mercapturic acids was also measured. The activity of aldehyde dehydrogenase, which catalyzes the oxidation and detoxification of aldehydes, tended to be higher in the liver of DHA-fed rats. The levels of lipid peroxides as measured by thiobarbituric acid-reactive substances and aldehydic compounds were higher and that of alpha-tocopherol was lower in the liver, and the pattern of temporal changes in the urinary excretion of mercapturic acids was also different between the n-6 linoleic acid and DHA-fed rats. Accordingly, we presume from these results that after dietary DHA-induced lipid peroxidation, a proportion of the lipid peroxidation-derived aldehydic degradation products is excreted into urine as mercapturic acids.

Urinary Lactate Dehydrogenase Activity and Its Isozyme Patterns in Kawasaki Disease

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Yoichi Kawamura

2017-01-01

Full Text Available Abnormal urinary findings, such as sterile pyuria, proteinuria, and microscopic hematuria, are often seen in the acute phase of Kawasaki disease (KD. We investigated the potential significance of urinary lactate dehydrogenase (U-LDH activity and its isozyme patterns in KD. Total U-LDH activity and its isozymes (U-LDH1-5 levels were compared among 120 patients with KD, 18 patients with viral infection (VI, and 43 patients with upper urinary tract infection (UTI and additionally compared between intravenous immunoglobulin (IVIG responders (n=89 and nonresponders (n=31 with KD. Total U-LDH activity was higher in KD (35.4±4.8 IU/L, P<0.05 and UTI patients (66.0±8.0 IU/L, P<0.01 than in VI patients (17.0±6.2 IU/L. In the isozyme pattern analysis, KD patients had high levels of U-LDH1 and U-LDH2, while UTI patients had high levels of U-LDH3, U-LDH4, and U-LDH5. Furthermore, IVIG nonresponders of KD had significantly higher levels of total U-LDH activity (45.1±4.7 IU/L, P<0.05, especially U-LDH1 and U-LDH2 (P<0.05, than IVIG responders (32.0±2.8 IU/L. KD patients have increased levels of total U-LDH activity, especially U-LDH-1 and U-LDH2, indicating a unique pattern of U-LDH isozymes different from that in UTI patients.

Forms of n-3 (ALA, C18:3n-3 or DHA, C22:6n-3) Fatty Acids Affect Carcass Yield, Blood Lipids, Muscle n-3 Fatty Acids and Liver Gene Expression in Lambs.

Science.gov (United States)

Ponnampalam, Eric N; Lewandowski, Paul A; Fahri, Fahri T; Burnett, Viv F; Dunshea, Frank R; Plozza, Tim; Jacobs, Joe L

2015-11-01

The effects of supplementing diets with n-3 alpha-linolenic acid (ALA) and docosahexaenoic acid (DHA) on plasma metabolites, carcass yield, muscle n-3 fatty acids and liver messenger RNA (mRNA) in lambs were investigated. Lambs (n = 120) were stratified to 12 groups based on body weight (35 ± 3.1 kg), and within groups randomly allocated to four dietary treatments: basal diet (BAS), BAS with 10.7 % flaxseed supplement (Flax), BAS with 1.8 % algae supplement (DHA), BAS with Flax and DHA (FlaxDHA). Lambs were fed for 56 days. Blood samples were collected on day 0 and day 56, and plasma analysed for insulin and lipids. Lambs were slaughtered, and carcass traits measured. At 30 min and 24 h, liver and muscle samples, respectively, were collected for determination of mRNA (FADS1, FADS2, CPT1A, ACOX1) and fatty acid composition. Lambs fed Flax had higher plasma triacylglycerol, body weight, body fat and carcass yield compared with the BAS group (P DHA supplementation increased carcass yield and muscle DHA while lowering plasma insulin compared with the BAS diet (P DHA treatment increased (P DHA concentration. Liver mRNA FADS2 was higher and CPT1A lower in the DHA group (P DHA diet. In summary, supplementation with ALA or DHA modulated plasma metabolites, muscle DHA, body fat and liver gene expression differently.

A study of associations between early DHA status and fatty acid desaturase (FADS) SNP and developmental outcomes in children of obese mothers.

Science.gov (United States)

Andersen, Karina R; Harsløf, Laurine B S; Schnurr, Theresia M; Hansen, Torben; Hellgren, Lars I; Michaelsen, Kim F; Lauritzen, Lotte

2017-01-01

DHA from diet or endogenous synthesis has been proposed to affect infant development, however, results are inconclusive. In this study, we aim to verify previously observed fatty acid desaturase gene cluster (FADS) SNP-specific associations with erythrocyte DHA status in 9-month-old children and sex-specific association with developmental outcomes. The study was performed in 166 children (55 % boys) of obese mothers. Erythrocyte fatty acid composition was analysed in blood-samples obtained at 9 months of age, and developmental outcomes assessed by the Ages and Stages Questionnaire at 3 years. Erythrocyte DHA level ranged from 4·4 to 9·9 % of fatty acids, but did not show any association with FADS SNP or other potential determinants. Regression analysis showed associations between erythrocyte DHA and scores for personal-social skills (β 1·8 (95 % CI 0·3, 3·3), P=0·019) and problem solving (β 3·4 (95 % CI 1·2, 5·6), P=0·003). A tendency was observed for an association in opposite direction between minor alleles (G-variant) of rs1535 and rs174575 and personal-social skills (P=0·062 and 0·068, respectively), which became significant when the SNP were combined based on their previously observed effect on erythrocyte DHA at 9 months of age (β 2·6 (95 % CI 0·01, 5·1), P=0·011). Sex-SNP interaction was indicated for rs174575 genotype on fine motor scores (P=0·016), due to higher scores among minor allele carrying girls (P=0·043), whereas no effect was seen among boys. In conclusion, DHA-increasing FADS SNP and erythrocyte DHA status were consistently associated with improved personal-social skills in this small cohort of children of obese mothers irrespective of sex, but the sample was too small to verify potential sex-specific effects.

Continuous gradient temperature Raman spectroscopy and differential scanning calorimetry of N-3DPA and DHA from -100 to 10°C

Science.gov (United States)

Docosahexaenoic acid (DHA, 22:6n-3) is exclusively utilized in fast signal processing tissues such as retinal, neural and cardiac. N-3 docosapentaenoic acid (n-3DPA, 22:5n-3), with just one less double bond, is also found in the marine food chain yet cannot substitute for DHA. Gradient Temperature R...

A Survey of Soil Enzyme Activities along Major Roads in Beijing: The Implications for Traffic Corridor Green Space Management

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Tianxin Li

2015-10-01

Full Text Available Soil quality is critical to the management of urban green space, in particular, along traffic corridors where traffic-related air pollution is significant. Soil quality can be evaluated by soil enzyme activities, which show quick responses to both natural and anthropogenic disturbances. In this study, we investigated three soil enzyme activities (i.e., dehydrogenase, catalase and urease along the major roads in urban areas of Beijing. Results show the activities of dehydrogenase, catalase and urease in urban samples were 58.8%, 68.2% and 48.5% less than the rural sample, respectively. The content of fluorescent amino acids as indicators of microbial activities was also consistently lower in urban samples than the rural. We observed two times greater exposure of particulate material along the roadsides in urban areas than rural areas. Although traffic air pollutants provide some nutrient sources to stimulate the URE activity, the exposure to traffic-related air pollution leads to the substantial decrease in enzyme activities. There were significant negative correlations for exposure to PM10 with DHA (r = −0.8267, p = 0.0017 and CAT (r = −0.89, p = 0.0002 activities. For the urban soils URE activity increased with the increasing of PM. We conclude that the degraded soil quality can negatively affect the target of developing plants and green spaces along the traffic corridors to mitigate the traffic impact. This study suggests the investigation of integrated strategies to restore the soil quality, reinforce the ecological service functions of green spaces along the traffic corridors and reduce the traffic pollutants.

Nutritional Evaluation of an EPA-DHA Oil from Transgenic Camelina sativa in Feeds for Post-Smolt Atlantic Salmon (Salmo salar L..

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Mónica B Betancor

Full Text Available Vegetable oils (VO are possible substitutes for fish oil in aquafeeds but their use is limited by their lack of omega-3 (n-3 long-chain polyunsaturated fatty acids (LC-PUFA. However, oilseed crops can be modified to produce n-3 LC-PUFA such as eicosapentaenoic (EPA and docosahexaenoic (DHA acids, representing a potential option to fill the gap between supply and demand of these important nutrients. Camelina sativa was metabolically engineered to produce a seed oil with around 15% total n-3 LC-PUFA to potentially substitute for fish oil in salmon feeds. Post-smolt Atlantic salmon (Salmo salar were fed for 11-weeks with one of three experimental diets containing either fish oil (FO, wild-type Camelina oil (WCO or transgenic Camelina oil (DCO as added lipid source to evaluate fish performance, nutrient digestibility, tissue n-3 LC-PUFA, and metabolic impact determined by liver transcriptome analysis. The DCO diet did not affect any of the performance or health parameters studied and enhanced apparent digestibility of EPA and DHA compared to the WCO diet. The level of total n-3 LC-PUFA was higher in all the tissues of DCO-fed fish than in WCO-fed fish with levels in liver similar to those in fish fed FO. Endogenous LC-PUFA biosynthetic activity was observed in fish fed both the Camelina oil diets as indicated by the liver transcriptome and levels of intermediate metabolites such as docosapentaenoic acid, with data suggesting that the dietary combination of EPA and DHA inhibited desaturation and elongation activities. Expression of genes involved in phospholipid and triacylglycerol metabolism followed a similar pattern in fish fed DCO and WCO despite the difference in n-3 LC-PUFA contents.

Nutritional Evaluation of an EPA-DHA Oil from Transgenic Camelina sativa in Feeds for Post-Smolt Atlantic Salmon (Salmo salar L.).

Science.gov (United States)

Betancor, Mónica B; Sprague, Matthew; Sayanova, Olga; Usher, Sarah; Metochis, Christoforos; Campbell, Patrick J; Napier, Johnathan A; Tocher, Douglas R

2016-01-01

Vegetable oils (VO) are possible substitutes for fish oil in aquafeeds but their use is limited by their lack of omega-3 (n-3) long-chain polyunsaturated fatty acids (LC-PUFA). However, oilseed crops can be modified to produce n-3 LC-PUFA such as eicosapentaenoic (EPA) and docosahexaenoic (DHA) acids, representing a potential option to fill the gap between supply and demand of these important nutrients. Camelina sativa was metabolically engineered to produce a seed oil with around 15% total n-3 LC-PUFA to potentially substitute for fish oil in salmon feeds. Post-smolt Atlantic salmon (Salmo salar) were fed for 11-weeks with one of three experimental diets containing either fish oil (FO), wild-type Camelina oil (WCO) or transgenic Camelina oil (DCO) as added lipid source to evaluate fish performance, nutrient digestibility, tissue n-3 LC-PUFA, and metabolic impact determined by liver transcriptome analysis. The DCO diet did not affect any of the performance or health parameters studied and enhanced apparent digestibility of EPA and DHA compared to the WCO diet. The level of total n-3 LC-PUFA was higher in all the tissues of DCO-fed fish than in WCO-fed fish with levels in liver similar to those in fish fed FO. Endogenous LC-PUFA biosynthetic activity was observed in fish fed both the Camelina oil diets as indicated by the liver transcriptome and levels of intermediate metabolites such as docosapentaenoic acid, with data suggesting that the dietary combination of EPA and DHA inhibited desaturation and elongation activities. Expression of genes involved in phospholipid and triacylglycerol metabolism followed a similar pattern in fish fed DCO and WCO despite the difference in n-3 LC-PUFA contents.

Crystallization and preliminary X-ray diffraction analysis of the wild-type haloalkane dehalogenase DhaA and its variant DhaA13 complexed with different ligands

Czech Academy of Sciences Publication Activity Database

Stsiapanava, A.; Chaloupková, R.; Fořtová, A.; Brynda, Jiří; Weiss, M.S.; Damborský, J.; Kutá-Smatanová, Ivana

2011-01-01

Roč. 67, - (2011), s. 253-257 ISSN 1744-3091 R&D Projects: GA MŠk(CZ) LC06010 Grant - others:GA ČR(CZ) GA310/09/1407 Program:GA Institutional research plan: CEZ:AV0Z50520514; CEZ:AV0Z60870520 Keywords : haloalkane dehalogenases * DhaA * Rhodococcus rhodochrous * microseeding * atomic resolution Subject RIV: EB - Genetics ; Molecular Biology; CD - Macromolecular Chemistry (UEK-B) Impact factor: 0.506, year: 2011

Regulation of the activity of lactate dehydrogenases from four lactic acid bacteria

NARCIS (Netherlands)

Feldman-Salit, A.; Hering, S.; Messiha, H.L.; Veith, N.; Cojocaru, V.; Sieg, A.; Westerhoff, H.V.; Kreikemeyer, B.; Wade, R.C.; Fiedler, T.

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

Zinc and glutamate dehydrogenase in putative glutamatergic brain structures.

Science.gov (United States)

Wolf, G; Schmidt, W

1983-01-01

A certain topographic parallelism between the distribution of histochemically (TIMM staining) identified zinc and putative glutamatergic structures in the rat brain was demonstrated. Glutamate dehydrogenase as a zinc containing protein is in consideration to be an enzyme synthesizing transmitter glutamate. In a low concentration range externally added zinc ions (10(-9) to 10(-7) M) induced an increase in the activity of glutamate dehydrogenase (GDH) originating from rat hippocampal formation, neocortex, and cerebellum up to 142.4%. With rising molarity of Zn(II) in the incubation medium, the enzyme of hippocampal formation and cerebellum showed a biphasic course of activation. Zinc ions of a concentration higher than 10(-6) M caused a strong inhibition of GDH. The effect of Zn(II) on GDH originating from spinal ganglia and liver led only to a decrease of enzyme activity. These results are discussed in connection with a functional correlation between zinc and putatively glutamatergic system.

Corneal aldehyde dehydrogenase and glutathione S-transferase activity after excimer laser keratectomy in guinea pigs.

Science.gov (United States)

Bilgihan, K; Bilgihan, A; Hasanreisoğlu, B; Turkozkan, N

1998-03-01

The free radical balance of the eye may be changed by excimer laser keratectomy. Previous studies have demonstrated that excimer laser keratectomy increases the corneal temperature, decreases the superoxide dismutase activity of the aqueous, and induces lipid peroxidation in the superficial corneal stroma. Aldehyde dehydrogenase (ALDH) and glutathione S-transferase (GST) are known to play an important role in corneal metabolism, particularly in detoxification of aldehydes, which are generated from free radical reactions. In three groups of guinea pigs mechanical corneal de-epithelialisation was performed in group I, superficial corneal photoablation in group II, and deep corneal photoablation in group III, and the corneal ALDH and GST activities measured after 48 hours. The mean ALDH and GST activities of group I and II showed no differences compared with the controls (p > 0.05). The corneal ALDH activities were found to be significantly decreased (p < 0.05) and GST activities increased (p < 0.05) in group III. These results suggest that excimer laser treatment of high myopia may change the ALDH and GST activities, metabolism, and free radical balance of the cornea.

Characterization of Oilseed Lipids from “DHA-Producing Camelina sativa”: A New Transformed Land Plant Containing Long-Chain Omega-3 Oils

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Maged P. Mansour

2014-02-01

Full Text Available New and sustainable sources of long-chain (LC, ≥C20 omega-3 oils containing DHA (docosahexaenoic acid, 22:6ω3 are required to meet increasing demands. The lipid content of the oilseed of a novel transgenic, DHA-producing land plant, Camelina sativa, containing microalgal genes able to produce LC omega-3 oils, contained 36% lipid by weight with triacylglycerols (TAG as the major lipid class in hexane extracts (96% of total lipid. Subsequent chloroform-methanol (CM extraction recovered further lipid (~50% polar lipid, comprising glycolipids and phospholipids and residual TAG. The main phospholipid species were phosphatidyl choline and phosphatidyl ethanolamine. The % DHA was: 6.8% (of total fatty acids in the TAG-rich hexane extract and 4.2% in the polar lipid-rich CM extract. The relative level of ALA (α-linolenic acid, 18:3ω3 in DHA-camelina seed was higher than the control. Major sterols in both DHA- and control camelina seeds were: sitosterol, campesterol, cholesterol, brassicasterol and isofucosterol. C16–C22 fatty alcohols, including iso-branched and odd-chain alcohols were present, including high levels of iso-17:0, 17:0 and 19:0. Other alcohols present were: 16:0, iso-18:0, 18:0 and 18:1 and the proportions varied between the hexane and CM extracts. These iso-branched odd-chain fatty alcohols, to our knowledge, have not been previously reported. These components may be derived from wax esters, or free fatty alcohols.

Designing a highly active soluble PQQ-glucose dehydrogenase for efficient glucose biosensors and biofuel cells

Energy Technology Data Exchange (ETDEWEB)

Durand, Fabien [Universite de Bordeaux, Centre de Recherche Paul Pascal (CRPP), UPR 8641, Avenue Albert Schweitzer, 33600 Pessac (France); Stines-Chaumeil, Claire [Universite de Bordeaux, CNRS, Institut de Biochimie et de Genetique Cellulaires, 1 rue Camille Saint Saens, 33077 Bordeaux Cedex (France); Flexer, Victoria [Universite de Bordeaux, Centre de Recherche Paul Pascal (CRPP), UPR 8641, Avenue Albert Schweitzer, 33600 Pessac (France); Andre, Isabelle [Universite de Toulouse, INSA, UPS, INP, LISBP, 135 Avenue de Rangueil, F-31077 Toulouse (France); CNRS, UMR5504, F-31400 Toulouse (France); INRA, UMR 792 Ingenierie des Systemes Biologiques et des Procedes, F-31400 Toulouse (France); Mano, Nicolas, E-mail: mano@crpp-bordeaux.cnrs.fr [Universite de Bordeaux, Centre de Recherche Paul Pascal (CRPP), UPR 8641, Avenue Albert Schweitzer, 33600 Pessac (France)

2010-11-26

Research highlights: {yields} A new mutant of PQQ-GDH designed for glucose biosensors application. {yields} First mutant of PQQ-GDH with higher activity for D-glucose than the Wild type. {yields} Position N428 is a key point to increase the enzyme activity. {yields} Molecular modeling shows that the N428 C mutant displays a better interaction for PQQ than the WT. -- Abstract: We report for the first time a soluble PQQ-glucose dehydrogenase that is twice more active than the wild type for glucose oxidation and was obtained by combining site directed mutagenesis, modelling and steady-state kinetics. The observed enhancement is attributed to a better interaction between the cofactor and the enzyme leading to a better electron transfer. Electrochemical experiments also demonstrate the superiority of the new mutant for glucose oxidation and make it a promising enzyme for the development of high-performance glucose biosensors and biofuel cells.

Purification of 2-oxo acid dehydrogenase multienzyme complexes from ox heart by a new method.

OpenAIRE

Stanley, C J; Perham, R N

1980-01-01

A new method is described that allows the parallel purification of the pyruvate dehydrogenase and 2-oxoglutarate dehydrogenase multienzyme complexes from ox heart without the need for prior isolation of mitochondria. All the assayable activity of the 2-oxo acid dehydrogenase complexes in the disrupted tissue is made soluble by the inclusion of non-ionic detergents such as Triton X-100 or Tween-80 in the buffer used for the initial extraction of the enzyme complexes. The yields of the pyruvate...

Very long chain acyl-coenzyme A dehydrogenase deficiency with adult onset

DEFF Research Database (Denmark)

Smelt, A H; Poorthuis, B J; Onkenhout, W

1998-01-01

Very long chain acyl-coenzyme A (acyl-CoA) dehydrogenase (VLCAD) deficiency is a severe disorder of mitochondrial beta-oxidation in infants. We report adult onset of attacks of painful rhabdomyolysis. Gas chromatography identified strongly elevated levels of tetradecenoic acid, 14:1(n-9), tetrade......Very long chain acyl-coenzyme A (acyl-CoA) dehydrogenase (VLCAD) deficiency is a severe disorder of mitochondrial beta-oxidation in infants. We report adult onset of attacks of painful rhabdomyolysis. Gas chromatography identified strongly elevated levels of tetradecenoic acid, 14:1(n-9......), tetradecadienoic acid, 14:2(n-6), and hexadecadienoic acid, 16:2(n-6). Palmitoyl-CoA and behenoyl-CoA dehydrogenase in fibroblasts were deficient. Muscle VLCAD activity was very low. DNA analysis revealed compound heterozygosity for two missense mutations in the VLCAD gene. The relatively mild clinical course may...... be due to residual enzyme activity as a consequence of the two missense mutations. Treatment with L-carnitine and medium chain triglycerides in the diet did not reduce the attacks of rhabdomyolysis....

O-Alkyl Hydroxamates as Metaphors of Enzyme-Bound Enolate Intermediates in Hydroxy Acid Dehydrogenases. Inhibitors of Isopropylmalate Dehydrogenase, Isocitrate Dehydrogenase, and Tartrate Dehydrogenase(1).

Science.gov (United States)

Pirrung, Michael C.; Han, Hyunsoo; Chen, Jrlung

1996-07-12

The inhibition of Thermus thermophilus isopropylmalate dehydrogenase by O-methyl oxalohydroxamate was studied for comparison to earlier results of Schloss with the Salmonella enzyme. It is a fairly potent (1.2 &mgr;M), slow-binding, uncompetitive inhibitor against isopropylmalate and is far superior to an oxamide (25 mM K(i) competitive) that is isosteric with the ketoisocaproate product of the enzyme. This improvement in inhibition was attributed to its increased NH acidity, which presumably is due to the inductive effect of the hydroxylamine oxygen. This principle was extended to the structurally homologous enzyme isocitrate dehydrogenase from E. coli, for which the compound O-(carboxymethyl) oxalohydroxamate is a 30 nM inhibitor, uncompetitive against isocitrate. The pH dependence of its inhibition supports the idea that it is bound to the enzyme in the anionic form. Another recently discovered homologous enzyme, tartrate dehydrogenase from Pseudomonas putida, was studied with oxalylhydroxamate. It has a relatively low affinity for the enzyme, though it is superior to tartrate. On the basis of these leads, squaric hydroxamates with increased acidity compared to squaric amides directed toward two of these enzymes were prepared, and they also show increased inhibitory potency, though not approaching the nanomolar levels of the oxalylhydroxamates.

Interaction of fructose with other medium components to affect bioproduction of docosahexaenoic acid (DHA) by Aurantiochytrium sp. SW1

Science.gov (United States)

Manikan, Vidyah; Kalil, Mohd. Sahaid; Shuib, Shuwahida; Hamid, Aidil Abdul

2018-04-01

Thraustochytrids are a group of marine fungus-like microheterotrophs of which some can accumulate considerable amounts of the high valued omega-3 oil, docosahexaenoic acid (DHA). In this study, a local thraustochytrid isolate, Aurantiochytrium sp. SW1, was cultivated in a medium containing fructose as the major carbon source. The effects of this carbon source in interaction with yeast extract, monosodium glutamate (MSG) and sea salt were studied using a software-based two level full factorial design. Results showed that fructose as a single factor, has significant positive effect on the volumetric DHA content of SW1. Similarly, its interaction with yeast extract has profound positive effect. However, interactions of fructose with MSG and sea salt were significant negative effects. These results indicate that manipulation of the concentration of fructose in the culture medium may serve as a simple and useful strategy to help achieve preferred amount of DHA.

Genetics Home Reference: dihydropyrimidine dehydrogenase deficiency

Science.gov (United States)

... 5-fluorouracil and capecitabine. These drugs are not broken down efficiently by people with dihydropyrimidine dehydrogenase deficiency ... of this enzyme. Because fluoropyrimidine drugs are also broken down by the dihydropyrimidine dehydrogenase enzyme, deficiency of ...

Omega-3 fatty acid oxidation products prevent vascular endothelial cell activation by coplanar polychlorinated biphenyls

International Nuclear Information System (INIS)

Majkova, Zuzana; Layne, Joseph; Sunkara, Manjula; Morris, Andrew J.; Toborek, Michal; Hennig, Bernhard

2011-01-01

Coplanar polychlorinated biphenyls (PCBs) may facilitate development of atherosclerosis by stimulating pro-inflammatory pathways in the vascular endothelium. Nutrition, including fish oil-derived long-chain omega-3 fatty acids, such as docosahexaenoic acid (DHA, 22:6ω-3), can reduce inflammation and thus the risk of atherosclerosis. We tested the hypothesis that cyclopentenone metabolites produced by oxidation of DHA can protect against PCB-induced endothelial cell dysfunction. Oxidized DHA (oxDHA) was prepared by incubation of the fatty acid with the free radical generator 2,2-azo-bis(2-amidinopropane) dihydrochloride (AAPH). Cellular pretreatment with oxDHA prevented production of superoxide induced by PCB77, and subsequent activation of nuclear factor-κB (NF-κB). A 4 /J 4 -neuroprostanes (NPs) were identified and quantitated using HPLC ESI tandem mass spectrometry. Levels of these NPs were markedly increased after DHA oxidation with AAPH. The protective actions of oxDHA were reversed by treatment with sodium borohydride (NaBH 4 ), which concurrently abrogated A 4 /J 4 -NP formation. Up-regulation of monocyte chemoattractant protein-1 (MCP-1) by PCB77 was markedly reduced by oxDHA, but not by un-oxidized DHA. These protective effects were proportional to the abundance of A 4 /J 4 NPs in the oxidized DHA sample. Treatment of cells with oxidized eicosapentaenoic acid (EPA, 20:5ω-3) also reduced MCP-1 expression, but less than oxDHA. Treatment with DHA-derived cyclopentenones also increased DNA binding of NF-E2-related factor-2 (Nrf2) and downstream expression of NAD(P)H:quinone oxidoreductase (NQO1), similarly to the Nrf-2 activator sulforaphane. Furthermore, sulforaphane prevented PCB77-induced MCP-1 expression, suggesting that activation of Nrf-2 mediates the observed protection against PCB77 toxicity. Our data implicate A 4 /J 4 -NPs as mediators of omega-3 fatty acid-mediated protection against the endothelial toxicity of coplanar PCBs.

Comparative analysis of succinate dehydrogenase activity in mammalian peripheral blood lymphocytes and radiomodifying action of gas hypoxis mixtures

International Nuclear Information System (INIS)

Gajdamakin, A.N.; Abramov, M.M.

1987-01-01

Radiprotective efficiency of gas hypoxic mixtures (GHM) containing 5-12% of oxygen and the rate of the reaction of succinate dehydrogenase (V SDG ) activity in peripheral blood lymphocytes upon breathing GHM were comparatively studied in rats and dogs. V SDG was 4393.5 (%O 2 ) -2,58 and 130.76 (%O 2 ) -1.42 in dogs and rats respectively. Taking into account that DMF in rats is a function of oxygen concentration in the mixture one can obtain a formula for determining a dose modifying factors (DMF) as a function of the rate of SDG activity reaction

Lactate Dehydrogenase and Oxidative Stress Activity in Primary Open-Angle Glaucoma Aqueous Humour

Directory of Open Access Journals (Sweden)

Predrag Jovanović

2010-02-01

Full Text Available 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.

Dietary ALA, EPA and DHA have distinct effects on oxylipin profiles in female and male rat kidney, liver and serum.

Science.gov (United States)

Leng, Shan; Winter, Tanja; Aukema, Harold M

2018-04-18

There is much data on the effects of dietary n-3 fatty acids on tissue fatty acid compositions, but comparable comprehensive data on their oxygenated metabolites (oxylipins) is limited. The effects of providing female and male rats with diets high in α-linolenic acid (ALA), EPA or DHA for 6 weeks on oxylipins and fatty acids in kidney, liver and serum were therefore examined. The oxylipin profile generally reflected fatty acids, but it also revealed unique effects of individual n-3 fatty acids that were not apparent from fatty acid data alone. Dietary ALA increased renal and serum DHA oxylipins even though DHA itself did not increase, while dietary EPA did not increase DHA oxylipins in kidney or liver, suggesting that high EPA may inhibit this conversion. Oxylipin data generally corroborated fatty acid data that indicated that DHA can be retroconverted to EPA and that further retroconversion to ALA is limited. Dietary n-3 fatty acids decreased n-6 fatty acids and their oxylipins (except linoleic acid and its oxylipins), in order of effectiveness of DHA > EPA > ALA, with some exceptions: several arachidonic acid oxylipins modified at carbon 15 were not lower in all three sites, and EPA had a greater effect on 12-hydroxy-eicosatetraenoic acid and its metabolites in the liver. Oxylipins were predominantly higher in males, which was not reflective of fatty acids. Tissue-specific oxylipin profiles, therefore, provide further information on individual dietary n-3 fatty acid and sex effects that may help explain their unique physiological effects and have implications for dietary recommendations. Copyright © 2018 Elsevier Inc. All rights reserved.

Characterization of the L-lactate dehydrogenase from Aggregatibacter actinomycetemcomitans.

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Stacie A Brown

Full Text Available Aggregatibacter actinomycetemcomitans is a Gram-negative opportunistic pathogen and the proposed causative agent of localized aggressive periodontitis. A. actinomycetemcomitans is found exclusively in the mammalian oral cavity in the space between the gums and the teeth known as the gingival crevice. Many bacterial species reside in this environment where competition for carbon is high. A. actinomycetemcomitans utilizes a unique carbon resource partitioning system whereby the presence of L-lactate inhibits uptake of glucose, thus allowing preferential catabolism of L-lactate. Although the mechanism for this process is not fully elucidated, we previously demonstrated that high levels of intracellular pyruvate are critical for L-lactate preference. As the first step in L-lactate catabolism is conversion of L-lactate to pyruvate by lactate dehydrogenase, we proposed a model in which the A. actinomycetemcomitans L-lactate dehydrogenase, unlike homologous enzymes, is not feedback inhibited by pyruvate. This lack of feedback inhibition allows intracellular pyruvate to rise to levels sufficient to inhibit glucose uptake in other bacteria. In the present study, the A. actinomycetemcomitans L-lactate dehydrogenase was purified and shown to convert L-lactate, but not D-lactate, to pyruvate with a K(m of approximately 150 microM. Inhibition studies reveal that pyruvate is a poor inhibitor of L-lactate dehydrogenase activity, providing mechanistic insight into L-lactate preference in A. actinomycetemcomitans.

Continuous gradient temperature Raman spectroscopy and differential scanning calorimetry of N-3DPA and DHA from -100 to 10°C.

Science.gov (United States)

Broadhurst, C Leigh; Schmidt, Walter F; Nguyen, Julie K; Qin, Jianwei; Chao, Kuanglin; Aubuchon, Steven R; Kim, Moon S

2017-04-01

Docosahexaenoic acid (DHA, 22:6n-3) is exclusively utilized in fast signal processing tissues such as retinal, neural and cardiac. N-3 docosapentaenoic acid (n-3DPA, 22:5n-3), with just one less double bond, is also found in the marine food chain yet cannot substitute for DHA. Gradient temperature Raman spectroscopy (GTRS) applies the temperature gradients utilized in differential scanning calorimetry (DSC) to Raman spectroscopy, providing a straightforward technique to identify molecular rearrangements that occur near and at phase transitions. Herein we apply GTRS and both conventional and modulated DSC to n-3DPA and DHA from -100 to 20°C. Three-dimensional data arrays with 0.2°C increments and first derivatives allowed complete assignment of solid, liquid and transition state vibrational modes. Melting temperatures n-3DPA (-45°C) and DHA (-46°C) are similar and show evidence for solid-state phase transitions not seen in n-6DPA (-27°C melt). The C6H2 site is an elastic marker for temperature perturbation of all three lipids, each of which has a distinct three dimensional structure. N-3 DPA shows the spectroscopic signature of saturated fatty acids from C1 to C6. DHA does not have three aliphatic carbons in sequence; n-6DPA does but they occur at the methyl end, and do not yield the characteristic signal. DHA appears to have uniform twisting from C6H2 to C12H2 to C18H2 whereas n-6DPA bends from C12 to C18, centered at C15H2. For n-3DPA, twisting is centered at C6H2 adjacent to the C2-C3-C4-C5 aliphatic moiety. These molecular sites are the most elastic in the solid phase and during premelting. Copyright © 2017 Elsevier B.V. All rights reserved.

Arginyl-glutamine dipeptide or docosahexaenoic acid attenuates hyperoxia-induced small intestinal injury in neonatal mice.

Science.gov (United States)

Li, Nan; Ma, Liya; Liu, Xueyan; Shaw, Lynn; Li Calzi, Sergio; Grant, Maria B; Neu, Josef

2012-04-01

Supplementation studies of glutamine, arginine, and docosahexaenoic acid (DHA) have established the safety of each of these nutrients in neonates; however, the potential for a more stable and soluble dipeptide, arginyl-glutamine (Arg-Gln) or DHA with anti-inflammatory properties, to exert benefits on hyperoxia-induced intestinal injury has not been investigated. Arg-Gln dipeptide has been shown to prevent retinal damage in a rodent model of oxygen-induced injury. The objective of the present study was to investigate whether Arg-Gln dipeptide or DHA could also attenuate markers of injury and inflammation to the small intestine in this same model. Seven-day-old mouse pups were placed with their dams in 75% oxygen for 5 days. After 5 days of hyperoxic exposure (P7-P12), pups were removed from hyperoxia and allowed to recover in atmospheric conditions for 5 days (P12-P17). Mouse pups received Arg-Gln (5g·kg·day) or DHA (5g·kg·day) or vehicle orally started on P12 through P17. Distal small intestine (DSI) histologic changes, myeloperoxidase (MPO), lactate dehydrogenase (LDH), inflammatory cytokines, and tissue apoptosis were evaluated. Hyperoxic mice showed a greater distortion of overall villus structure and with higher injury score (PDHA supplementation groups were more similar to the room air control group. Supplementation of Arg-Gln or DHA reduced hyperoxia-induced MPO activity (PDHA returned LDH activity to the levels of control. Hyperoxia induced apoptotic cell death in DSIs, and both Arg-Gln and DHA reversed this effect (PDHA may limit some inflammatory and apoptotic processes involved in hyperoxic-induced intestinal injury in neonatal mice.

Preparation of triacylglycerols rich in omega-3 fatty acids from sardine oil using a Rhizomucor miehei lipase: focus in the EPA/DHA ratio.

Science.gov (United States)

Bispo, Paulo; Batista, Irineu; Bernardino, Raul J; Bandarra, Narcisa Maria

2014-02-01

The increasing evidence on the differential biochemical effects of eicosapentaenoic acid (EPA)/docosahexaenoic acid (DHA) raises the need of n-3 highly unsaturated fatty acid concentrates with different amounts of these fatty acids. In the present work, physicochemical and enzymatic techniques were combined to obtain acylglycerols, mainly triacylglycerols (TAG), rich in n-3 fatty acids. Sardine oil was obtained by washing sardine (Sardina pilchardus) mince with a NaHCO3 solution, hydrolyzed in a KOH-ethanol solution, and concentrated with urea. The esterification reaction was performed in the stoichiometric proportion of substrates for re-esterification to TAG, with 10 % level of Rhizomucor miehei lipase based on the weight of substrates, without any solvent, during 48 h. This procedure led to approximately 88 % of acylglycerols, where more than 66 % were TAG and the concentration of n-3 fatty acids was higher than 60 %, the EPA and DHA ratio (EPA/DHA) was 4:1. The content of DHA in the unesterifed fraction (free fatty acids) increased from 20 to 54 %, while the EPA level in the same fraction decreased from 33 to 12.5 % (EPA/DHA ratio ≈1:4). Computational methods (density functional theory calculations) have been carried out at the B3LYP/6-31G(d,p) level to explain some of the experimental results.

A single arginine residue is required for the interaction of the electron transferring flavoprotein (ETF) with three of its dehydrogenase partners.

Science.gov (United States)

Parker, Antony R

2003-12-01

The interaction of several dehydrogenases with the electron transferring flavoprotein (ETF) is a crucial step required for the successful transfer of electrons into the electron transport chain. The exact determinants regarding the interaction of ETF with its dehydrogenase partners are still unknown. Chemical modification of ETF with arginine-specific reagents resulted in the loss, to varying degrees, of activity with medium chain acyl-coenzyme A dehydrogenase (MCAD). The kinetic profiles showed the inactivations followed pseudo-first-order kinetics for all reagents used. For activity with MCAD, maximum inactivation of ETF was accomplished by 2,3-butanedione (4% residual activity after 120 min) and it was shown that modification of one arginine residue was responsible for the inactivation. Almost 100% restoration of this ETF activity was achieved upon incubation with free arginine. However, the same 2,3-butanedione modified ETF only possessed decreased activity with dimethylglycine-(DMGDH, 44%) and sarcosine- (SDH, 27%) dehydrogenases unlike the abolition with MCAD. Full protection of ETF from arginine modification by 2,3-butanedione was achieved using substrate-protected DMGDH, MCAD and SDH respectively. Cross-protection studies of ETF with the three dehydrogenases implied use of the same single arginine residue in the binding of all three dehydrogenases. These results lead us to conclude that this single arginine residue is essential in the binding of the ETF to MCAD, but only contributes partially to the binding of ETF to SDH and DMGDH and thus, the determinants of the dehydrogenase binding sites overlap but are not identical.

CLA isomer t10,c12 induce oxidation and apoptosis in 3t3 adipocyte cells in a similar effect as omega-3 linolenic acid and DHA.

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Jon Meadus

2017-02-01

Full Text Available Background: Commercial conjugated linoleic acid (CLA dietary supplements contain an equal mixture of the C18:2 isomers, cis-9trans-11 and trans-10cis-12. Predominantly, CLA-c9t11 occurs naturally in meat and dairy products at ~ 0.5% of total fat , whereas CLA-t10c12 occurs at >0.1%. Recent studies show that CLA-c9t11 generally promotes lipid accumulation but CLA-t10c12 may inhibit lipid accumulation and may also promote inflammation. The omega-3 fatty acids α-linolenic acid (C18:3n-3 and docosahexaenoic acid (DHA have also been observed to inhibit lipid accumulation and effect inflammation; therefore we examined the effects of the two main isomersof CLA and omega -3 fatty acids C18:3n-3 and DHA at the molecular levelto determine if they are causing similar oxidative stresses.Methods:Purified CLA-c9t11 and CLA-t10c12 were added to 3T3 cells induced into mature adipocyte cultures at 100uM concentrations and compared with 100uM C18:3n-3(α-linolenic acid and 50uM docosahexaenoic acid (DHA to observe their effect on growth, gene transcription and general oxidation. The results of multiple separate trials were averaged and compared for significance at levels of P< 0.05, using one way ANOVA and Student’s t-test.Results:C18:3n-3, DHA and CLA-t10c12inhibited 3T3 adipose cell growth and caused a significant increase in lipid hydro peroxide activity. CLA-t10c12 and c9t11 increased AFABP, FAS and ACOX1 mRNA gene expression but DHA and C18:3n-3decreased the same mRNAs. CLA-c9t11 but not the t10c12 stimulated adipoQ expression even though; CLA-c9t11 had only a slightly greater affinity for PPARγ than CLA-t10c12, according to TR-FRET assays. The expression of the xenobiotic metabolism genes, aldo-keto reduct as 1c1 (akr1c1, superoxide dismutase (SODand inflammation chemokine secretions of eotaxin (CCL11, Rantes (CCL5, MIG (CCL9 and MCP-1 were increased by DHA, C18:3n-3and CLA-t10c12 but not CLA-c9t11. This correlated with an increase in apoptosis factors

Increased superoxide accumulation in pyruvate dehydrogenase complex deficient fibroblasts.

Science.gov (United States)

Glushakova, Lyudmyla G; Judge, Sharon; Cruz, Alex; Pourang, Deena; Mathews, Clayton E; Stacpoole, Peter W

2011-11-01

The pyruvate dehydrogenase complex (PDC) oxidizes pyruvate to acetyl CoA and is critically important in maintaining normal cellular energy homeostasis. Loss-of-function mutations in PDC give rise to congenital lactic acidosis and to progressive cellular energy failure. However, the subsequent biochemical consequences of PDC deficiency that may contribute to the clinical manifestations of the disorder are poorly understood. We postulated that altered flux through PDC would disrupt mitochondrial electron transport, resulting in oxidative stress. Compared to cells from 4 healthy subjects, primary cultures of skin fibroblasts from 9 patients with variable mutations in the gene encoding the alpha subunit (E1α) of pyruvate dehydrogenase (PDA1) demonstrated reduced growth and viability. Superoxide (O(2)(.-)) from the Qo site of complex III of the electron transport chain accumulated in these cells and was associated with decreased activity of manganese superoxide dismutase. The expression of uncoupling protein 2 was also decreased in patient cells, but there were no significant changes in the expression of cellular markers of protein or DNA oxidative damage. The expression of hypoxia transcription factor 1 alpha (HIF1α) also increased in PDC deficient fibroblasts. We conclude that PDC deficiency is associated with an increase in O(2)(.-) accumulation coupled to a decrease in mechanisms responsible for its removal. Increased HIF1α expression may contribute to the increase in glycolytic flux and lactate production in PDC deficiency and, by trans-activating pyruvate dehydrogenase kinase, may further suppress residual PDC activity through phosphorylation of the E1α subunit. Copyright © 2011 Elsevier Inc. All rights reserved.

Ethanol production by anaerobic thermophilic bacteria: regulation of lactate dehydrogenase activity in Clostridium thermohydrosulfuricum

Energy Technology Data Exchange (ETDEWEB)

Germain, P; Toukourou, F; Donaduzzi, L

1986-07-01

The enzyme lactate dehydrogenase (LDH) in Clostridium thermohydrosulfuricum is controlled by the type and the concentration of the substrate. In batch fermentations an increase of the initial concentration of glucose leads to an increase in the activity of LDH. This increase in activity is related to the accumulation of fructose 1,6-diphosphate (F 1,6-DP), an intermediate of the Embden-Meyerhof-Parnas (EMP) pathway, which stimulates the enzyme by increasing its affinity for pyruvate and NADH. The Ksub(m) values of LDH for pyruvate and NADH, which are 2.5 x 10/sup -3/ M and 9.1 x 10/sup -5/ M respectively in absence of F 1,6-DP, fall considerably in the presence of this substrate. In presence of 0.2 mM of F 1,6-DP we observed a Ksub(m) of 3.3 x 10/sup -4/ M for pyruvate and 4.1 x 10/sup -5/ M for NADH.

Effect of ionizing radiation on the colour and activity of lactate dehydrogenase of pork

International Nuclear Information System (INIS)

Dvorak, P.; Salplachta, J.; Grolichova, M.

2006-01-01

The most significant sensory and quality characteristic of meat is colour. The effect of irradiation of pork was studied in relation to color changes. Samples of M. longissimus lumborum et thoracic were obtained from the pork carcasses 24 h post mortem. Samples were irradiated using a 60 Co source, at dose of 2.5 and 5 kGy; dose rate of 2.86 kGy/h. Unirradiated controls were stored in the same condition as irradiated samples. Measurement of colour was realised with portable spectrophotometer Superchroma S-Spex in CIELAB system. The colour of a freshly cut interior surface of control and irradiated pork was measured before and after irradiation. L * and b * values of controls and irradiated pork did not change after irradiation. The a * values (red colour) of irradiated pork were significantly higher than unirradiated. The activity of lactate dehydrogenase of pork was measured after irradiation. The activity did not change after irradiation. (authors)

Single-cell analysis of dihydroartemisinin-induced apoptosis through reactive oxygen species-mediated caspase-8 activation and mitochondrial pathway in ASTC-a-1 cells using fluorescence imaging techniques

Science.gov (United States)

Lu, Ying-Ying; Chen, Tong-Sheng; Wang, Xiao-Ping; Li, Li

2010-07-01

Dihydroartemisinin (DHA), a front-line antimalarial herbal compound, has been shown to possess promising anticancer activity with low toxicity. We have previously reported that DHA induced caspase-3-dependent apoptosis in human lung adenocarcinoma cells. However, the cellular target and molecular mechanism of DHA-induced apoptosis is still poorly defined. We use confocal fluorescence microscopy imaging, fluorescence resonance energy transfer, and fluorescence recovery after photobleaching techniques to explore the roles of DHA-elicited reactive oxygen species (ROS) in the DHA-induced Bcl-2 family proteins activation, mitochondrial dysfunction, caspase cascade, and cell death. Cell Counting Kit-8 assay and flow cytometry analysis showed that DHA induced ROS-mediated apoptosis. Confocal imaging analysis in a single living cell and Western blot assay showed that DHA triggered ROS-dependent Bax translocation, mitochondrial membrane depolarization, alteration of mitochondrial morphology, cytochrome c release, caspase-9, caspase-8, and caspase-3 activation, indicating the coexistence of ROS-mediated mitochondrial and death receptor pathway. Collectively, our findings demonstrate for the first time that DHA induces cell apoptosis by triggering ROS-mediated caspase-8/Bid activation and the mitochondrial pathway, which provides some novel insights into the application of DHA as a potential anticancer drug and a new therapeutic strategy by targeting ROS signaling in lung adenocarcinoma therapy in the future.

Quantitative comparison between the gel-film and polyvinyl alcohol methods for dehydrogenase histochemistry reveals different intercellular distribution patterns of glucose-6-phosphate and lactate dehydrogenases in mouse liver

NARCIS (Netherlands)

Griffini, P.; Vigorelli, E.; Bertone, V.; Freitas, I.; van Noorden, C. J.

1994-01-01

The precise histochemical localization and quantification of the activity of soluble dehydrogenases in unfixed cryostat sections requires the use of tissue protectants. In this study, two protectants, polyvinyl alcohol (PVA) and agarose gel, were compared for assaying the activity of lactate

Structural characterization of the thermostable Bradyrhizobium japonicumD-sorbitol dehydrogenase.

Science.gov (United States)

Fredslund, Folmer; Otten, Harm; Gemperlein, Sabrina; Poulsen, Jens Christian N; Carius, Yvonne; Kohring, Gert Wieland; Lo Leggio, Leila

2016-11-01

Bradyrhizobium japonicum sorbitol dehydrogenase is NADH-dependent and is active at elevated temperatures. The best substrate is D-glucitol (a synonym for D-sorbitol), although L-glucitol is also accepted, giving it particular potential in industrial applications. Crystallization led to a hexagonal crystal form, with crystals diffracting to 2.9 Å resolution. In attempts to phase the data, a molecular-replacement solution based upon PDB entry 4nbu (33% identical in sequence to the target) was found. The solution contained one molecule in the asymmetric unit, but a tetramer similar to that found in other short-chain dehydrogenases, including the search model, could be reconstructed by applying crystallographic symmetry operations. The active site contains electron density consistent with D-glucitol and phosphate, but there was not clear evidence for the binding of NADH. In a search for the features that determine the thermostability of the enzyme, the T m for the orthologue from Rhodobacter sphaeroides, for which the structure was already known, was also determined, and this enzyme proved to be considerably less thermostable. A continuous β-sheet is formed between two monomers in the tetramer of the B. japonicum enzyme, a feature not generally shared by short-chain dehydrogenases, and which may contribute to thermostability, as may an increased Pro/Gly ratio.

Diglycolic acid inhibits succinate dehydrogenase activity in human proximal tubule cells leading to mitochondrial dysfunction and cell death.

Science.gov (United States)

Landry, Greg M; Dunning, Cody L; Conrad, Taylor; Hitt, Mallory J; McMartin, Kenneth E

2013-08-29

Diethylene glycol (DEG) is a solvent used in consumer products allowing the increased risk for consumer exposure. DEG metabolism produces two primary metabolites, 2-hydroxyethoxyacetic acid (2-HEAA) and diglycolic acid (DGA). DGA has been shown to be the toxic metabolite responsible for the proximal tubule cell necrosis seen in DEG poisoning. The mechanism of DGA toxicity in the proximal tubule cell is not yet known. The chemical structure of DGA is very similar to citric acid cycle intermediates. Studies were designed to assess whether its mechanism of toxicity involves disruption of cellular metabolic pathways resulting in mitochondrial dysfunction. First, DGA preferentially inhibited succinate dehydrogenase, including human kidney cell enzyme, but had no effect on other citric acid cycle enzyme activities. DGA produces a cellular ATP depletion that precedes cell death. Human proximal tubule (HPT) cells, pre-treated with increasing DGA concentrations, showed significantly decreased oxygen consumption. DGA did not increase lactate levels, indicating no effect on glycolytic activity. DGA increased reactive oxygen species (ROS) production in HPT cells in a concentration and time dependent manner. These results indicate that DGA produced proximal tubule cell dysfunction by specific inhibition of succinate dehydrogenase and oxygen consumption. Disruption of these processes results in decreased energy production and proximal tubule cell death. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

Predicting the effect of maternal docosahexaenoic acid (DHA) supplementation to reduce early preterm birth in Australia and the United States using results of within country randomized controlled trials

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Yelland, LN; Gajewski, BJ; Colombo, J; Gibson, RA; Makrides, M; Carlson, SE

2016-01-01

SUMMARY The DHA to Optimize Mother Infant Outcome (DOMInO) and Kansas DHA Outcomes Study (KUDOS) were randomized controlled trials that supplemented mothers with 800 and 600 mg DHA/day, respectively, or a placebo during pregnancy. DOMInO was conducted in Australia and KUDOS in the United States. Both trials found an unanticipated and statistically significant reduction in early preterm birth (ePTB; i.e., birth before 34 weeks gestation). However, in each trial, the number of ePTBs were small. We used a novel Bayesian approach and an arbitrary sample of 120,000 pregnancies to estimate statistically derived low, moderate or high risk for ePTB, and to test for differences between the DHA and placebo groups. In both trials, the model predicted DHA would significantly reduce the expected proportion of deliveries in the high risk group under the trial conditions of the parent studies. From these proportions we estimated the number of ePTB that could be prevented. PMID:27637340

Electrochemical Studies of the Inhibition and Activation Effects of Al (III on the Activity of Bovine Liver Glutamate Dehydrogenase

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Shuping Bi

2005-04-01

Full Text Available Since the study of Al3+ ion on the enzyme activity by using of electrochemical techniques was rarely found in available literatures, the differential-pulse polarography (DPP technique was applied to study the effects of Al3+ ion on the glutamate dehydrogenase (GDH activity in the catalytical reaction of α-KG +NADH+NH4 + ⇔ L-Glu+NAD++H2O by monitoring the DPP reduction current of NAD+. At the plant and animal physiologically relevant pH values (pH=6.5 and 7.5, the GDH enzyme activities were strongly depended on the concentrations of the metal ion in the assay mixture solutions. In the lower Al (III concentration solutions (80μM, the inhibition effects of Al (III were shown again. The cyclic voltammetry of NAD+ and NAD+-GDH in the presence of Al (III can help to explain some biological phenomena. According to the differential-pulse polarography and cyclic voltammetry experiments, the present research confirmed that the electrochemical technique is a convenient and reliable sensor for accurate determination of enzyme activity in biological and environmental samples.

Effects of n-3 fatty acids, EPA v. DHA, on depressive symptoms, quality of life, memory and executive function in older adults with mild cognitive impairment: a 6-month randomised controlled trial.

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Sinn, Natalie; Milte, Catherine M; Street, Steven J; Buckley, Jonathan D; Coates, Alison M; Petkov, John; Howe, Peter R C

2012-06-01

Depressive symptoms may increase the risk of progressing from mild cognitive impairment (MCI) to dementia. Consumption of n-3 PUFA may alleviate both cognitive decline and depression. The aim of the present study was to investigate the benefits of supplementing a diet with n-3 PUFA, DHA and EPA, for depressive symptoms, quality of life (QOL) and cognition in elderly people with MCI. We conducted a 6-month double-blind, randomised controlled trial. A total of fifty people aged >65 years with MCI were allocated to receive a supplement rich in EPA (1·67 g EPA + 0·16 g DHA/d; n 17), DHA (1·55 g DHA + 0·40 g EPA/d; n 18) or the n-6 PUFA linoleic acid (LA; 2·2 g/d; n 15). Treatment allocation was by minimisation based on age, sex and depressive symptoms (Geriatric Depression Scale, GDS). Physiological and cognitive assessments, questionnaires and fatty acid composition of erythrocytes were obtained at baseline and 6 months (completers: n 40; EPA n 13, DHA n 16, LA n 11). Compared with the LA group, GDS scores improved in the EPA (P=0·04) and DHA (P=0·01) groups and verbal fluency (Initial Letter Fluency) in the DHA group (P=0·04). Improved GDS scores were correlated with increased DHA plus EPA (r 0·39, P=0·02). Improved self-reported physical health was associated with increased DHA. There were no treatment effects on other cognitive or QOL parameters. Increased intakes of DHA and EPA benefited mental health in older people with MCI. Increasing n-3 PUFA intakes may reduce depressive symptoms and the risk of progressing to dementia. This needs to be investigated in larger, depressed samples with MCI.

Recovery of Corneal Sensitivity and Increase in Nerve Density and Wound Healing in Diabetic Mice After PEDF Plus DHA Treatment.

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He, Jiucheng; Pham, Thang Luong; Kakazu, Azucena; Bazan, Haydee E P

2017-09-01

Diabetic keratopathy decreases corneal sensation and tear secretion and delays wound healing after injury. In the current study, we tested the effect of treatment with pigment epithelium-derived factor (PEDF) in combination with docosahexaenoic acid (DHA) on corneal nerve regeneration in a mouse model of diabetes with or without corneal injury. The study was performed in streptozotocin-induced diabetic mice (C57BL/6). Ten weeks after streptozotocin injection, diabetic mice showed significant decreases of corneal sensitivity, tear production, and epithelial subbasal nerve density when compared with age-matched normal mice. After diabetic mice were wounded in the right eye and treated in both eyes with PEDF+DHA for 2 weeks, there was a significant increase in corneal epithelial nerve regeneration and substance P-positive nerve density in both wounded and unwounded eyes compared with vehicle-treated corneas. There also was elevated corneal sensitivity and tear production in the treated corneas compared with vehicle. In addition, PEDF+DHA accelerated corneal wound healing, selectively recruited type 2 macrophages, and prevented neutrophil infiltration in diabetic wounded corneas. These results suggest that topical treatment with PEDF+DHA promotes corneal nerve regeneration and wound healing in diabetic mice and could potentially be exploited as a therapeutic option for the treatment of diabetic keratopathy. © 2017 by the American Diabetes Association.

Effect of low dose x irradiation on the succinate dehydrogenase activity of guinea pig, rat and mouse tissues

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Shah, V C; Bhatavdekar, J M; Aravinda Babu, K [Gujarat Univ., Ahmedabad (India). Dept. of Zoology

1976-07-01

The histochemical changes in succinate dehydrogenase (SDH) were investigated in pectoralis major muscle of guinea pig, rat and mouse after level X-irradiation (72 R and 240 R) and compared with control animals. Biochemical studies were carried out on liver, kidney, muscle (pectoralis major), adrenal and spleen of these animals after low dose local X-irradiation and compared with control animals. Changes in SDH activity were studied up to 72-h post-irradiation, which shows that low dose local X-irradiation leads to increased enzymic activity. The increase in enzymic activity was remarkable in mouse tissues as compared with guinea pig and rat. Adrenals of all the three animals showed significant activation after all the doses of radiation studied. The significance of these results, with special reference to oxidative metabolism, has been discussed.

High performance liquid chromatography method for the determination of cinnamyl alcohol dehydrogenase activity in soybean roots.

Science.gov (United States)

dos Santos, W D; Ferrarese, Maria de Lourdes Lucio; Ferrarese-Filho, O

2006-01-01

This study proposes a simple, quick and reliable method for determining the cinnamyl alcohol dehydrogenase (CAD; EC 1.1.1.195) activity in soybean (Glycine max L. Merr.) roots using reversed-phase high performance liquid chromatography (RP-HPLC). The method includes a single extraction of the tissue and conduction of the enzymatic reaction at 30 degrees C with cinnamaldehydes (coniferyl or sinapyl), substrates of CAD. Disappearance of the substrates in the reaction mixture is monitored at 340 nm (for coniferaldehyde) or 345 nm (for sinapaldehyde) by isocratic elution with methanol/acetic acid through a GLC-ODS (M) column. This HPLC technique furnishes a rapid and reliable measure of cinnamaldehyde substrates, and may be used as an alternative tool to analyze CAD activity in enzyme preparation without previous purification.

In Vitro Activity of Imipenem and Colistin against a Carbapenem-Resistant Klebsiella pneumoniae Isolate Coproducing SHV-31, CMY-2, and DHA-1

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Hung-Jen Tang

2015-01-01

Full Text Available We investigated the synergism of colistin and imipenem against a multidrug-resistant K. pneumoniae isolate which was recovered from a severe hip infection. PCR and DNA sequencing were used to characterize the outer membrane porin genes and the resistance genes mediating the common β-lactamases and carbapenemases. Synergism was evaluated by time-kill studies. The blaSHV-31, blaCMY-2, and blaDHA-1 were detected. Outer membrane porin genes analysis revealed loss of ompK36 and frame-shift mutation of ompK35. The common carbapenemase genes were not found. Time-kill studies demonstrated that a combination of 1x MIC of colistin (2 mg/L and 1x MIC of imipenem (8 mg/L was synergistic and bactericidal but with inoculum effect. Bactericidal activity without inoculum effect was observed by concentration of 2x MIC of colistin alone or plus 2x MIC of imipenem. In conclusion, colistin plus imipenem could be an alternative option to treat carbapenem-resistant K. pneumoniae infections.

Reduced activity of 11beta-hydroxysteroid dehydrogenase type 2 is not responsible for sodium retention in nephrotic rats

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Bistrup, C; Thiesson, H C; Jensen, B L

2005-01-01

AIM: In mineralocorticoid target cells 11-beta-hydroxysteroid dehydrogenase type 2 (11betaHSD2) converts glucocorticoids into non-active metabolites thereby protecting the mineralocorticoid receptor (MR) from stimulation by glucocorticoids. In nephrotic syndrome, a decreased activity of 11betaHSD2...... has been suggested to allow glucocorticoids to stimulate MR, thereby contributing to sodium retention. We tested this hypothesis in the puromycin aminonucleoside model of nephrotic syndrome in rats. METHODS: Complete sodium and potassium intakes and excretions (faeces and urine) were measured in rats......)] to suppress endogenous glucocorticoids in the proteinuric stage during active sodium retention. RESULTS: Nephrotic rats developed proteinuria, positive sodium balance, decreased plasma aldosterone concentration, and decreased urinary Na(+)/K(+) ratio. 11betaHSD2 mRNA expression was down-regulated but protein...

Nutritional Ingredients Modulate Adipokine Secretion and Inflammation in Human Primary Adipocytes

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Romacho, Tania; Glosse, Philipp; Richter, Isabel; Elsen, Manuela; Schoemaker, Marieke H.; van Tol, Eric A.; Eckel, Jürgen

2015-01-01

Nutritional factors such as casein hydrolysates and long chain polyunsaturated fatty acids have been proposed to exert beneficial metabolic effects. We aimed to investigate how a casein hydrolysate (eCH) and long chain polyunsaturated fatty acids could affect human primary adipocyte function in vitro. Incubation conditions with the different nutritional factors were validated by assessing cell vitality with lactate dehydrogenase (LDH) release and neutral red incorporation. Intracellular triglyceride content was assessed with Oil Red O staining. The effect of eCH, a non-peptidic amino acid mixture (AA), and long-chain polyunsaturated fatty acids (LC-PUFAs) on adiponectin and leptin secretion was determined by enzyme-linked immunosorbent assay (ELISA). Intracellular adiponectin expression and nuclear factor-κB (NF-κB) activation were analyzed by Western blot, while monocyte chemoattractant protein-1 (MCP-1) release was explored by ELISA. The eCH concentration dependently increased adiponectin secretion in human primary adipocytes through its intrinsic peptide bioactivity, since the non-peptidic mixture, AA, could not mimic eCH’s effects on adiponectin secretion. Eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA), and DHA combined with arachidonic acid (ARA) upregulated adiponectin secretion. However, only DHA and DHA/ARA exerted a potentanti-inflammatory effect reflected by prevention of tumor necrosis factor-α (TNF-α) induced NF-κB activation and MCP-1 secretion in human adipocytes. eCH and DHA alone or in combination with ARA, may hold the key for nutritional programming through their anti-inflammatory action to prevent diseases with low-grade chronic inflammation such as obesity or diabetes. PMID:25629558

Nutritional Ingredients Modulate Adipokine Secretion and Inflammation in Human Primary Adipocytes

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Tania Romacho

2015-01-01

Full Text Available Nutritional factors such as casein hydrolysates and long chain polyunsaturated fatty acids have been proposed to exert beneficial metabolic effects. We aimed to investigate how a casein hydrolysate (eCH and long chain polyunsaturated fatty acids could affect human primary adipocyte function in vitro. Incubation conditions with the different nutritional factors were validated by assessing cell vitality with lactate dehydrogenase (LDH release and neutral red incorporation. Intracellular triglyceride content was assessed with Oil Red O staining. The effect of eCH, a non-peptidic amino acid mixture (AA, and long-chain polyunsaturated fatty acids (LC-PUFAs on adiponectin and leptin secretion was determined by enzyme-linked immunosorbent assay (ELISA. Intracellular adiponectin expression and nuclear factor-κB (NF-κB activation were analyzed by Western blot, while monocyte chemoattractant protein-1 (MCP-1 release was explored by ELISA. The eCH concentration dependently increased adiponectin secretion in human primary adipocytes through its intrinsic peptide bioactivity, since the non-peptidic mixture, AA, could not mimic eCH’s effects on adiponectin secretion. Eicosapentaenoic acid (EPA, docosahexaenoic acid (DHA, and DHA combined with arachidonic acid (ARA upregulated adiponectin secretion. However, only DHA and DHA/ARA exerted a potentanti-inflammatory effect reflected by prevention of tumor necrosis factor-α (TNF-α induced NF-κB activation and MCP-1 secretion in human adipocytes. eCH and DHA alone or in combination with ARA, may hold the key for nutritional programming through their anti-inflammatory action to prevent diseases with low-grade chronic inflammation such as obesity or diabetes.

Enhancement of L-3-hydroxybutyryl-CoA dehydrogenase activity and circulating ketone body levels by pantethine. Relevance to dopaminergic injury.

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Cornille, Emilie; Abou-Hamdan, Mhamad; Khrestchatisky, Michel; Nieoullon, André; de Reggi, Max; Gharib, Bouchra

2010-04-23

The administration of the ketone bodies hydroxybutyrate and acetoacetate is known to exert a protective effect against metabolic disorders associated with cerebral pathologies. This suggests that the enhancement of their endogenous production might be a rational therapeutic approach. Ketone bodies are generated by fatty acid beta-oxidation, a process involving a mitochondrial oxido-reductase superfamily, with fatty acid-CoA thioesters as substrates. In this report, emphasis is on the penultimate step of the process, i.e. L-3-hydroxybutyryl-CoA dehydrogenase activity. We determined changes in enzyme activity and in circulating ketone body levels in the MPTP mouse model of Parkinson's disease. Since the active moiety of CoA is pantetheine, mice were treated with pantethine, its naturally-occurring form. Pantethine has the advantage of being known as an anti-inflammatory and hypolipidemic agent with very few side effects. We found that dehydrogenase activity and circulating ketone body levels were drastically reduced by the neurotoxin MPTP, whereas treatment with pantethine overcame these adverse effects. Pantethine prevented dopaminergic neuron loss and motility disorders. In vivo and in vitro experiments showed that the protection was associated with enhancement of glutathione (GSH) production as well as restoration of respiratory chain complex I activity and mitochondrial ATP levels. Remarkably, pantethine treatment boosted the circulating ketone body levels in MPTP-intoxicated mice, but not in normal animals. These finding demonstrate the feasibility of the enhancement of endogenous ketone body production and provide a promising therapeutic approach to Parkinson's disease as well as, conceivably, to other neurodegenerative disorders.

Enhancement of L-3-hydroxybutyryl-CoA dehydrogenase activity and circulating ketone body levels by pantethine. Relevance to dopaminergic injury

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de Reggi Max

2010-04-01

Full Text Available Abstract Background The administration of the ketone bodies hydroxybutyrate and acetoacetate is known to exert a protective effect against metabolic disorders associated with cerebral pathologies. This suggests that the enhancement of their endogenous production might be a rational therapeutic approach. Ketone bodies are generated by fatty acid beta-oxidation, a process involving a mitochondrial oxido-reductase superfamily, with fatty acid-CoA thioesters as substrates. In this report, emphasis is on the penultimate step of the process, i.e. L-3-hydroxybutyryl-CoA dehydrogenase activity. We determined changes in enzyme activity and in circulating ketone body levels in the MPTP mouse model of Parkinson's disease. Since the active moiety of CoA is pantetheine, mice were treated with pantethine, its naturally-occurring form. Pantethine has the advantage of being known as an anti-inflammatory and hypolipidemic agent with very few side effects. Results We found that dehydrogenase activity and circulating ketone body levels were drastically reduced by the neurotoxin MPTP, whereas treatment with pantethine overcame these adverse effects. Pantethine prevented dopaminergic neuron loss and motility disorders. In vivo and in vitro experiments showed that the protection was associated with enhancement of glutathione (GSH production as well as restoration of respiratory chain complex I activity and mitochondrial ATP levels. Remarkably, pantethine treatment boosted the circulating ketone body levels in MPTP-intoxicated mice, but not in normal animals. Conclusions These finding demonstrate the feasibility of the enhancement of endogenous ketone body production and provide a promising therapeutic approach to Parkinson's disease as well as, conceivably, to other neurodegenerative disorders.

Maternal single nucleotide polymorphisms in the fatty acid desaturase 1 and 2 coding regions modify the impact of prenatal supplementation with DHA on birth weight.

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Gonzalez-Casanova, Ines; Rzehak, Peter; Stein, Aryeh D; Garcia Feregrino, Raquel; Rivera Dommarco, Juan A; Barraza-Villarreal, Albino; Demmelmair, Hans; Romieu, Isabelle; Villalpando, Salvador; Martorell, Reynaldo; Koletzko, Berthold; Ramakrishnan, Usha

2016-04-01

Specific single nucleotide polymorphisms (SNPs) in the fatty acid desaturase (FADS) gene affect the activity and efficiency of enzymes that are responsible for the conversion of polyunsaturated fatty acids (PUFAs) into their long-chain active form. A high prevalence of SNPs that are associated with slow PUFA conversion has been described in Hispanic populations. We assessed the heterogeneity of the effect of prenatal supplementation with docosahexaenoic acid (DHA) on birth weight across selected FADS SNPs in a sample of Mexican women and their offspring. We obtained information on the maternal genotype from stored blood samples of 654 women who received supplementation with 400 mg DHA/d or a placebo from weeks 18 to 22 of gestation through delivery as part of a randomized controlled trial conducted in Cuernavaca, Mexico. We selected 4 tag SNPs (rs174455, rs174556, rs174602, and rs498793) in the FADS region for analysis. We used an ANOVA to test for the heterogeneity of the effect on birth weight across each of the 4 SNPs. The mean ± SD birth weight was 3210 ± 470 g, and the weight-for-age z score (WAZ) was -0.24 ± 1.00. There were no intention-to-treat differences in birth weights. We showed significant heterogeneity by SNP rs174602 (P= 0.02); offspring of carriers of alleles TT and TC in the intervention group were heavier than those in the placebo group (WAZ: -0.13 ± 0.14 and -0.20 ± 0.08 compared with -0.55 ± 0.15 and -0.39 ± 0.09, respectively); there were no significant differences in offspring of rs174602 CC homozygotes (WAZ: -0.26 ± 0.09 in the intervention group compared with -0.04 ± 0.09 in the placebo group). We showed no significant heterogeneity across the other 3 FADS SNPs. Differential responses to prenatal DHA supplementation on the basis of the genetic makeup of target populations could explain the mixed evidence of the impact of DHA supplementation on birth weight. This trial was registered at clinicaltrials.gov as NCT00646360. © 2016

Lutein accumulates in subcellular membranes of brain regions in adult rhesus macaques: Relationship to DHA oxidation products.

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Emily S Mohn

Full Text Available Lutein, a carotenoid with anti-oxidant functions, preferentially accumulates in primate brain and is positively related to cognition in humans. Docosahexaenoic acid (DHA, an omega-3 polyunsaturated fatty acid (PUFA, is also beneficial for cognition, but is susceptible to oxidation. The present study characterized the membrane distribution of lutein in brain regions important for different domains of cognitive function and determined whether membrane lutein was associated with brain PUFA oxidation.Adult rhesus monkeys were fed a stock diet (~2 mg/day lutein or ~0.5 μmol/kg body weight/day (n = 9 or the stock diet plus a daily supplement of lutein (~4.5 mg/day or~1 μmol/kg body weight/day and zeaxanthin (~0.5 mg/day or 0.1 μmol/kg body weight/day for 6-12 months (n = 4. Nuclear, myelin, mitochondrial, and neuronal plasma membranes were isolated using a Ficoll density gradient from prefrontal cortex (PFC, cerebellum (CER, striatum (ST, and hippocampus (HC. Carotenoids, PUFAs, and PUFA oxidation products were measured using HPLC, GC, and LC-GC/MS, respectively.All-trans-lutein (ng/mg protein was detected in all regions and membranes and was highly variable among monkeys. Lutein/zeaxanthin supplementation significantly increased total concentrations of lutein in serum, PFC and CER, as well as lutein in mitochondrial membranes and total DHA concentrations in PFC only (P<0.05. In PFC and ST, mitochondrial lutein was inversely related to DHA oxidation products, but not those from arachidonic acid (P <0.05.This study provides novel data on subcellular lutein accumulation and its relationship to DHA oxidation in primate brain. These findings support the hypothesis that lutein may be associated with antioxidant functions in the brain.

Effects of whole body x-ray irradiation on induction by phenobarbital of rat liver glucose-6-phosphate dehydrogenase and glutathione reductase

Energy Technology Data Exchange (ETDEWEB)

Bitny-Szlachto, S.; Szyszko, A. (Wojskowy Inst. Higieny i Epidemiologii, Warsaw (Poland))

1979-01-01

In rats treated with phenobarbital (3x100 mg/kg, i.p.), liver G-6-P dehydrogenase activity increased by 70% in the cytosol and in the 9.000xg supernatant, and only by 20% in microsomes. Moreover, the phenobarbital treatment increased rat liver GSSG reductase activity by 30%. On the other hand, activity of the liver microsomal G-6-P dehydrogenase was found to increase by some 20% in whole body irradiated, both control and phenobarbital treated rats. In rats irradiated with 600 R prior to the first dose of the inducer there was not noted any increase in G-6-P dehydrogenase of the 9.000xg supernatant, and increase in the cytosol activity dropped to 38%. Thus, induction of the soluble liver G-6-P dehydrogenase by phenobarbital has turned out to be radiosensitive, whereas phenobarbital induction of GSSG reductase was unaffected by irradiation.

Overexpression of Lactobacillus casei D-hydroxyisocaproic acid dehydrogenase in cheddar cheese.

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Broadbent, Jeffery R; Gummalla, Sanjay; Hughes, Joanne E; Johnson, Mark E; Rankin, Scott A; Drake, Mary Anne

2004-08-01

Metabolism of aromatic amino acids by lactic acid bacteria is an important source of off-flavor compounds in Cheddar cheese. Previous work has shown that alpha-keto acids produced from Trp, Tyr, and Phe by aminotransferase enzymes are chemically labile and may degrade spontaneously into a variety of off-flavor compounds. However, dairy lactobacilli can convert unstable alpha-keto acids to more-stable alpha-hydroxy acids via the action of alpha-keto acid dehydrogenases such as d-hydroxyisocaproic acid dehydrogenase. To further characterize the role of this enzyme in cheese flavor, the Lactobacillus casei d-hydroxyisocaproic acid dehydrogenase gene was cloned into the high-copy-number vector pTRKH2 and transformed into L. casei ATCC 334. Enzyme assays confirmed that alpha-keto acid dehydrogenase activity was significantly higher in pTRKH2:dhic transformants than in wild-type cells. Reduced-fat Cheddar cheeses were made with Lactococcus lactis starter only, starter plus L. casei ATCC 334, and starter plus L. casei ATCC 334 transformed with pTRKH2:dhic. After 3 months of aging, the cheese chemistry and flavor attributes were evaluated instrumentally by gas chromatography-mass spectrometry and by descriptive sensory analysis. The culture system used significantly affected the concentrations of various ketones, aldehydes, alcohols, and esters and one sulfur compound in cheese. Results further indicated that enhanced expression of d-hydroxyisocaproic acid dehydrogenase suppressed spontaneous degradation of alpha-keto acids, but sensory work indicated that this effect retarded cheese flavor development.

Assay of partially purified glutamate dehydrogenase isolated from ...

African Journals Online (AJOL)

Glutamate dehydrogenase (E C 1.4.1.1) isolated from the seeds of asparagus beans was partially purified to a factor of 22 by dialysis after fractional precipitation with solid ammonium sulphate at 40 and 60% saturation. A specific activity of 11.78μmol min-1 mg-1 protein was calculated for the partially purified enzyme when ...

Novel guanidine-based inhibitors of inosine monophosphate dehydrogenase.

Science.gov (United States)

Iwanowicz, Edwin J; Watterson, Scott H; Liu, Chunjian; Gu, Henry H; Mitt, Toomas; Leftheris, Katerina; Barrish, Joel C; Fleener, Catherine A; Rouleau, Katherine; Sherbina, N Z; Hollenbaugh, Diane L

2002-10-21

A series of novel guanidine-based small molecule inhibitors of inosine monophosphate dehydrogenase (IMPDH) was explored. IMPDH catalyzes the rate determining step in guanine nucleotide biosynthesis and is a target for anticancer, immunosuppressive and antiviral therapy. The synthesis and the structure-activity relationships (SARs), derived from in vitro studies, for this new series of inhibitors is given.

A study of associations between early DHA status and fatty acid desaturase (FADS) SNP and developmental outcomes in children of obese mothers

DEFF Research Database (Denmark)

Andersen, Karina R; Harsløf, Laurine B S; Schnurr, Theresia M

2017-01-01

DHA from diet or endogenous synthesis has been proposed to affect infant development, however, results are inconclusive. In this study, we aim to verify previously observed fatty acid desaturase gene cluster (FADS) SNP-specific associations with erythrocyte DHA status in 9-month-old children...... and sex-specific association with developmental outcomes. The study was performed in 166 children (55 % boys) of obese mothers. Erythrocyte fatty acid composition was analysed in blood-samples obtained at 9 months of age, and developmental outcomes assessed by the Ages and Stages Questionnaire at 3 years......-increasing FADS SNP and erythrocyte DHA status were consistently associated with improved personal-social skills in this small cohort of children of obese mothers irrespective of sex, but the sample was too small to verify potential sex-specific effects....

Effects of an open-label pilot study with high-dose EPA/DHA concentrates on plasma phospholipids and behavior in children with attention deficit hyperactivity disorder

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Hutchins Heather L

2007-07-01

Full Text Available Abstract Background Attention deficit hyperactivity disorder (ADHD is the most common neurological condition in children. This pilot study evaluated the effects of high-dose eicosapentaenoic acid (EPA and docosahexaenoic acid (DHA supplementation on the isolated plasma phospholipids and behavior in children with ADHD (primarily inattentive subtype and combined subtype. Methods Nine children were initially supplemented with 16.2 g EPA/DHA concentrates per day. The dosage was adjusted dependent on the ratio of arachidonic acid (AA to EPA in the isolated plasma phospholipids at four weeks to reach a level normally found in the Japanese population. Results At the end of the eight-week study, supplementation resulted in significant increases in EPA and DHA, as well as a significant reduction in the AA:EPA ratio (20.78 ± 5.26 to 5.95 ± 7.35, p Conclusion The findings of this small pilot study suggest supplementation with high-dose EPA/DHA concentrates may improve behavior in children with ADHD.

A novel self-micro-emulsifying delivery system (SMEDS) formulation significantly improves the fasting absorption of EPA and DHA from a single dose of an omega-3 ethyl ester concentrate.

Science.gov (United States)

Qin, Yan; Nyheim, Hilde; Haram, Else Marie; Moritz, Joseph M; Hustvedt, Svein Olaf

2017-10-16

Absorption of EPA and DHA from Omega-3-acid ethyl ester (EE) concentrate supplements occurs most efficiently when taken in context of a fatty meal; adequate fat intake is required to release bile salts that emulsify and pancreatic enzymes that digest omega-3-containing lipids in the intestine. Current guidelines recommend reduction in fat intake and therefore there is a need to optimize the absorption of Omega-3 in those consuming low-fat or no-fat meals. To this end, BASF has developed an Absorption Acceleration Technology, a novel self-micro-emulsifying delivery system (SMEDS) formulation of highly concentrated Omega-3-acid EE which enables rapid emulsification and microdroplet formation upon entering the aqueous environment of the gut therefore enhances the absorption. Two separate single dose, crossover studies were conducted to determine the relative bioavailability of omega-3-acid EE concentrate, either as a novel SMEDS formulation (PRF-021) or as control, in healthy fasted male and female adults at two dose levels (Study 1 "low dose": 630 mg EPA + DHA in PRF-021 vs. 840 mg EPA + DHA in control; Study 2 "high dose": 1680 mg EPA + DHA in PRF-021 vs. 3360 mg EPA + DHA in control). Blood samples were collected immediately before supplementation and at defined time intervals for 48 h. Plasma concentration of total EPA and DHA were determined for pharmacokinetic analysis, area under the curve (AUC) and maximum observed concentration (C max ) was determined. Total EPA plus DHA absorption from SMEDS formulation PRF-021 were 6.4 and 11.5 times higher compared to control in low- and high-dose studies respectively, determined as the ratio of baseline corrected, dose normalized AUC 0-24h of PRF-021 over that of control. EPA and DHA individually showed differing levels of enhancement: the AUC 0-24h ratio for EPA was 23.8 and 25.7 in low and high dose studies, respectively, and the AUC 0-24h ratio for DHA was 3.6 and 5.6 in low and high dose studies

Purification of methanol dehydrogenase from mouth methylotrophic bacteria of tropical region

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Waturangi, D.

2011-01-01

Full Text Available Aims: Purification of methanol dehydrogenase (MDH from methylotrophic bacteria was conducted to obtain pure enzyme for further research and industrial applications due to the enzyme’s unique activity that catalyzes oxidation of methanol as an important carbon source in methylotrophic bacteria.Methodology and Results: The enzyme was screened from methylotrophic bacteria isolated from human mouth. Purification of this enzyme was conducted using ammonium sulphate precipitation followed by cation exchange chromatography. Two types of media were used to produce the enzymes: luria broth and standard mineral salts media (MSM. MSM produced MDH with higher specific activity than LB. Specific activity was also increased along with the purification steps. Application of ammonium sulphate increased the purity of enzyme and was more effective for the enzyme produced in LB. Using sepharose increased the enzyme activity 10 -57 folds.Conclusion, significant and impact of this study: With this, ammonium sulphate precipitation coupled with single cation exchange chromatographic system has been proved to provide sufficient purified of methanol dehydrogenase from methylotrophic bacteria origin of human mouth with high specific activity for further application.

Purification and characterization of the amine dehydrogenase from a facultative methylotroph.

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Coleman, J P; Perry, J J

1984-01-01

Strain RA-6 is a pink-pigmented organism which can grow on a variety of substrates including methylamine. It can utilize methylamine as sole source of carbon via an isocitrate lyase negative serine pathway. Methylamine grown cells contain an inducible primary amine dehydrogenase [primary amine: (acceptor) oxidoreductase (deaminating)] which is not present in succinate grown cells. The amine dehydrogenase was purified to over 90% homogeneity. It is an acidic protein (isoelectric point of 5.37) with a molecular weight of 118,000 containing subunits with approximate molecular weights of 16,500 and 46,000. It is active on an array of primary terminal amines and is strongly inhibited by carbonyl reagents. Cytochrome c or artificial electron acceptors are required for activity; neither NAD nor NADP can serve as primary electron acceptor.

Supplementation of docosahexaenoic acid (DHA) / Eicosapentaenoic acid (EPA) in a ratio of 1/1.3 during the last trimester of pregnancy results in EPA accumulation in cord blood.

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Büyükuslu, Nihal; Ovalı, Sema; Altuntaş, Şükriye Leyla; Batırel, Saime; Yiğit, Pakize; Garipağaoğlu, Muazzez

2017-10-01

Omega-3 fatty acids (n-3 FA), specifically DHA, are associated with fetal growth and development. We aimed to determine the levels of DHA and EPA in cord serum after n-3 FA supplementation during the last trimester of pregnancy. Among 55 women, 23 were administered daily one capsule of n-3 FA supplement, involving DHA/EPA in a ratio of 1/1.3. Twenty nine women were enrolled as control group. Blood samples were collected at 22-24 weeks of gestation and at delivery. Fatty acids were analyzed with the method of GC-MS. Cord DHA level increased and EPA level decreased in both groups between the days of 22-24 and delivery. However, decrease in cord EPA level was significant in control group (p 0.05). Supplementation of DHA/EPA in a ratio of 1/1.3 during the last trimester of pregnancy caused higher cord EPA level compared to control group indicating an accumulation in umbilical cord. Copyright © 2017 Elsevier Ltd. All rights reserved.

Natural Docosahexaenoic Acid in the Triglyceride Form Attenuates In Vitro Microglial Activation and Ameliorates Autoimmune Encephalomyelitis in Mice

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Pilar Mancera

2017-06-01

Full Text Available Many neurodegenerative diseases are associated, at least in part, to an inflammatory process in which microglia plays a major role. The effect of the triglyceride form of the omega-3 polyunsaturated fatty acid docosahexaenoic acid (TG-DHA was assayed in vitro and in vivo to assess the protective and anti-inflammatory activity of this compound. In the in vitro study, BV-2 microglia cells were previously treated with TG-DHA and then activated with Lipopolysaccharide (LPS and Interferon-gamma (IFN-γ. TG-DHA treatment protected BV-2 microglia cells from oxidative stress toxicity attenuating NO production and suppressing the induction of inflammatory cytokines. When compared with DHA in the ethyl-ester form, a significant difference in the ability to inhibit NO production in favor of TG-DHA was observed. TG-DHA inhibited significantly splenocyte proliferation but isolated CD4+ lymphocyte proliferation was unaffected. In a mice model of autoimmune encephalomyelitis (EAE, 250 mg/kg/day oral TG-DHA treatment was associated with a significant amelioration of the course and severity of the disease as compared to untreated animals. TG-DHA-treated EAE mice showed a better weight profile, which is a symptom related to a better course of encephalomyelitis. TG-DHA may be a promising therapeutic agent in neuroinflammatory processes and merit to be more extensively studied in human neurodegenerative disorders.

Acquired multiple Acyl-CoA dehydrogenase deficiency in 10 horses with atypical myopathy.

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Westermann, C M; Dorland, L; Votion, D M; de Sain-van der Velden, M G M; Wijnberg, I D; Wanders, R J A; Spliet, W G M; Testerink, N; Berger, R; Ruiter, J P N; van der Kolk, J H

2008-05-01

The aim of the current study was to assess lipid metabolism in horses with atypical myopathy. Urine samples from 10 cases were subjected to analysis of organic acids, glycine conjugates, and acylcarnitines revealing increased mean excretion of lactic acid, ethylmalonic acid, 2-methylsuccinic acid, butyrylglycine, (iso)valerylglycine, hexanoylglycine, free carnitine, C2-, C3-, C4-, C5-, C6-, C8-, C8:1-, C10:1-, and C10:2-carnitine as compared with 15 control horses (12 healthy and three with acute myopathy due to other causes). Analysis of plasma revealed similar results for these predominantly short-chain acylcarnitines. Furthermore, measurement of dehydrogenase activities in lateral vastus muscle from one horse with atypical myopathy indeed showed deficiencies of short-chain acyl-CoA dehydrogenase (0.66 as compared with 2.27 and 2.48 in two controls), medium-chain acyl-CoA dehydrogenase (0.36 as compared with 4.31 and 4.82 in two controls) and isovaleryl-CoA dehydrogenase (0.74 as compared with 1.43 and 1.61 nmol min(-1) mg(-1) in two controls). A deficiency of several mitochondrial dehydrogenases that utilize flavin adenine dinucleotide as cofactor including the acyl-CoA dehydrogenases of fatty acid beta-oxidation, and enzymes that degrade the CoA-esters of glutaric acid, isovaleric acid, 2-methylbutyric acid, isobutyric acid, and sarcosine was suspected in 10 out of 10 cases as the possible etiology for a highly fatal and prevalent toxic equine muscle disease similar to the combined metabolic derangements seen in human multiple acyl-CoA dehydrogenase deficiency also known as glutaric acidemia type II.

Effect of thoracic x-irradiation on glucose-6-phosphate dehydrogenase activity of the pectoral muscle of guinea pig

International Nuclear Information System (INIS)

Bhatavdekar, J.M.; Shah, V.C.

1981-01-01

The histochemical distribution of glucose-6-phosphate dehydrogenase (G6PD) was observed in the major pectoral muscle of a guinea pig that had received 240 R thoracic X-irradiation. The irradiation effects were studied at 24, 48 and 72 hrs after X-irradiation. Type I fibres of the pectoral muscle were deeply stained showing high activity whereas type II fibres demonstrated minimum enzyme activity. The intermediate fibres had medium levels of G6PD activity. Type II fibres showed more staining at 24 and 48 hrs as compared with control muscle. However, at 72 hrs all three fibre types showed a marked inhibition of G6PD activity. The significance of these changes suggests that muscle G6PD metabolism generally altered after irradiation, but the specific nature of these changes and their causes still remain unclear. (author)

Novel chiral tool, (R)-2-octanol dehydrogenase, from Pichia finlandica: purification, gene cloning, and application for optically active α-haloalcohols.

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Yamamoto, Hiroaki; Kudoh, Masatake

2013-09-01

A novel enantioselective alcohol dehydrogenase, (R)-2-octanol dehydrogenase (PfODH), was discovered among methylotrophic microorganisms. The enzyme was purified from Pichia finlandica and characterized. The molecular mass of the enzyme was estimated to be 83,000 and 30,000 by gel filtration and sodium dodecyl sulfate-polyacrylamide gel electrophoresis, respectively. The enzyme was an NAD(+)-dependent secondary alcohol dehydrogenase and showed a strict enantioselectivity, very broad substrate specificity, and high tolerance to SH reagents. A gene-encoding PfODH was cloned and sequenced. The gene consisted of 765 nucleotides, coding polypeptides of 254 amino acids. The gene was singly expressed and coexpressed together with a formate dehydrogenase as an NADH regenerator in an Escherichia coli. Ethyl (S)-4-chloro-3-hydroxybutanoate and (S)-2-chloro-1-phenylethanol were synthesized using a whole-cell biocatalyst in more than 99 % optical purity.

Kinetic characterization of recombinant Bacillus coagulans FDP-activated l-lactate dehydrogenase expressed in Escherichia coli and its substrate specificity.

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Jiang, Ting; Xu, Yanbing; Sun, Xiucheng; Zheng, Zhaojuan; Ouyang, Jia

2014-03-01

Bacillus coagulans is a homofermentative, acid-tolerant and thermophilic sporogenic lactic acid bacterium, which is capable of producing high yields of optically pure lactic acid. The l-(+)-lactate dehydrogenase (l-LDH) from B. coagulans is considered as an ideal biocatalyst for industrial production. In this study, the gene ldhL encoding a thermostable l-LDH was amplified from B. coagulans NL01 genomic DNA and successfully expressed in Escherichia coli BL21 (DE3). The recombinant enzyme was partially purified and its enzymatic properties were characterized. Sequence analysis demonstrated that the l-LDH was a fructose 1,6-diphosphate-activated NAD-dependent lactate dehydrogenase (l-nLDH). Its molecular weight was approximately 34-36kDa. The Km and Vmax values of the purified l-nLDH for pyruvate were 1.91±0.28mM and 2613.57±6.43μmol(minmg)(-1), respectively. The biochemical properties of l-nLDH showed that the specific activity were up to 2323.29U/mg with optimum temperature of 55°C and pH of 6.5 in the pyruvate reduction and 351.01U/mg with temperature of 55°C and pH of 11.5 in the lactate oxidation. The enzyme also showed some activity in the absence of FDP, with a pH optimum of 4.0. Compared to other lactic acid bacterial l-nLDHs, the enzyme was found to be relatively stable at 50°C. Ca(2+), Ba(2+), Mg(2+) and Mn(2+) ions had activated effects on the enzyme activity, and the enzyme was greatly inhibited by Ni(2+) ion. Besides these, l-nLDH showed the higher specificity towards pyruvate esters, such as methyl pyruvate and ethyl pyruvate. Copyright © 2014 Elsevier Inc. All rights reserved.

Glucose-6-phosphate dehydrogenase and glutathione reductase activity in methemoglobin reduction by methylene blue and cyst amine: study on glucose-6-phosphate dehydrogenase-deficient individuals, on normal subjects and on riboflavin-treated subjects

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Benedito Barraviera

1988-10-01

Full Text Available The authors have standardized methods for evaluation of the activity of the glucose-6-phosphate dehydrogenase and of glutathione reductase. The general principle of the first method was based on methemoglobin formation by sodium nitrite followed by stimulation of the glucose-6-phosphate dehydrogenase with methylene blue. Forty six adults (23 males and 23 females were studied. Subjects were not G6PD deficient and were aged 20 to 30 years. The results showed that methemoglobin reduction by methylene blue was 154.40 and 139.90 mg/min (p<0.05 for males and females, respectively, in whole blood, and 221.10 and 207.85 mg/min (n.s., respectively, in washed red cells. These data showed that using washed red cells and 0.7g% sodium nitrite concentration produced no differences between sexes and also shortened reading time for the residual amount of methemoglobin to 90 minutes. Glutathione reductase activity was evaluated on the basis of the fact that cystamine (a thiol agent binds to the SH groups of hemoglobin, forming complexes. These complexes are reversed by the action of glutathione reductase, with methemoglobin reduction occurring simultaneously with this reaction. Thirty two adults (16 males and 16 females were studied. Subjects were not G6PD deficient and were aged 20 to 30 years. Methemoglobin reduction by cystamine was 81.27 and 91.13 mg/min (p<0.01 for males and females, respectively. These data showed that using washed red cells and 0.1 M cystamine concentration permits a reading of the residual amount of methemoglobin at 180 minutes of incubation. Glutathione reductase activity was evaluated by methemoglobin reduction by cystamine in 14 females before and after treatment with 10 mg riboflavin per day for 8 days. The results were 73.69 and 94.26 jug/min (p<0.01 before and after treatment, showing that riboflavin treatment increase glutathione reductase activity even in normal individuals. Three Black G6PD-deficient individuals (2 males and 1

Regulation of pyruvate dehydrogenase kinase expression by the farnesoid X receptor

International Nuclear Information System (INIS)

Savkur, Rajesh S.; Bramlett, Kelli S.; Michael, Laura F.; Burris, Thomas P.

2005-01-01

The pyruvate dehydrogenase complex (PDC) functions as an important junction in intermediary metabolism by influencing the utilization of fat versus carbohydrate as a source of fuel. Activation of PDC is achieved by phosphatases, whereas, inactivation is catalyzed by pyruvate dehydrogenase kinases (PDKs). The expression of PDK4 is highly regulated by the glucocorticoid and peroxisome proliferator-activated receptors. We demonstrate that the farnesoid X receptor (FXR; NR1H4), which regulates a variety of genes involved in lipoprotein metabolism, also regulates the expression of PDK4. Treatment of rat hepatoma cells as well as human primary hepatocytes with FXR agonists stimulates the expression of PDK4 to levels comparable to those obtained with glucocorticoids. In addition, treatment of mice with an FXR agonist significantly increased hepatic PDK4 expression, while concomitantly decreasing plasma triglyceride levels. Thus, activation of FXR may suppress glycolysis and enhance oxidation of fatty acids via inactivation of the PDC by increasing PDK4 expression

The effect of organotin compounds on gender specific androstenedione metabolism in the freshwater ramshorn snail Marisa cornuarietis.

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Janer, G; Bachmann, J; Oehlmann, J; Schulte-Oehlmann, U; Porte, C

2006-05-01

In a recent study, we demonstrated that androstenedione was mainly converted to testosterone (T) and 5alpha-dihydrotestosterone (DHT) by digestive gland/gonad complex microsomal fractions isolated from male Marisa cornuarietis, whereas it was primarily metabolized to 5alpha-dihydroandrostenedione (DHA) by females. In the present work, the sexual dimorphic metabolism of androstenedione was further investigated, and attributed to a higher 17beta-hydroxysteroid dehydrogenase activity in males than in females. Thereafter, the hypothesis was tested that the metabolism of androstenedione might be affected by exposure to tributyltin (TBT) and triphenyltin (TPT), which are known to induce the development of imposex in several gastropod species. The in vitro metabolism of androstenedione, particularly the formation of DHA and DHT, was inhibited by both compounds. However, in vivo experiments showed no significant alteration in the metabolism of androstenedione in males, but a marginal (TBT) and a significant (TPT) inhibition of the formation of DHA in females exposed for 150 days to concentrations that had significantly induced the development of imposex. The ratio DHT+T/DHA, a possible indicator of metabolic androgenization, tended to increase (0.43 versus 0.35, p=0.06) in TPT exposed females. However, this ratio never reached values comparable to those found in males (11+/-1).

The activity state of the branched-chain 2-oxo acid dehydrogenase complex in rat tissues.

Science.gov (United States)

Wagenmakers, A J; Schepens, J T; Veldhuizen, J A; Veerkamp, J H

1984-05-15

An assay is described to define the proportion of the branched-chain 2-oxo acid dehydrogenase complex that is present in the active state in rat tissues. Activities are measured in homogenates in two ways: actual activities, present in tissues, by blocking both the kinase and phosphatase of the enzyme complex during homogenization, preincubation, and incubation with 1-14C-labelled branched-chain 2-oxo acid, and total activities by blocking only the kinase during the 5 min preincubation (necessary for activation). The kinase is blocked by 5 mM-ADP and absence of Mg2+ and the phosphatase by the simultaneous presence of 50 mM-NaF. About 6% of the enzyme is active in skeletal muscle of fed rats, 7% in heart, 20% in diaphragm, 47% in kidney, 60% in brain and 98% in liver. An entirely different assay, which measures activities in crude tissue extracts before and after treatment with a broad-specificity protein phosphatase, gave similar results for heart, liver and kidney. Advantages of our assay with homogenates are the presence of intact mitochondria, the simplicity, the short duration and the high sensitivity. The actual activities measured indicate that the degradation of branched-chain 2-oxo acids predominantly occurs in liver and kidney and is limited in skeletal muscle in the fed state.

Synthesis, Characterization, and In Vitro and In Vivo Evaluations of 4-(N-Docosahexaenoyl 2′, 2′-Difluorodeoxycytidine with Potent and Broad-Spectrum Antitumor Activity

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Youssef W. Naguib

2016-01-01

Full Text Available In this study, a new compound, 4-(N-docosahexaenoyl 2′, 2′-difluorodeoxycytidine (DHA-dFdC, was synthesized and characterized. Its antitumor activity was evaluated in cell culture and in mouse models of pancreatic cancer. DHA-dFdC is a poorly soluble, pale yellow waxy solid, with a molecular mass of 573.3 Da and a melting point of about 96°C. The activation energy for the degradation of DHA-dFdC in an aqueous Tween 80–based solution is 12.86 kcal/mol, whereas its stability is significantly higher in the presence of vitamin E. NCI-60 DTP Human Tumor Cell Line Screening revealed that DHA-dFdC has potent and broad-spectrum antitumor activity, especially in leukemia, renal, and central nervous system cancer cell lines. In human and murine pancreatic cancer cell lines, the IC50 value of DHA-dFdC was up to 105-fold lower than that of dFdC. The elimination of DHA-dFdC in mouse plasma appeared to follow a biexponential model, with a terminal phase t1/2 of about 58 minutes. DHA-dFdC significantly extended the survival of genetically engineered mice that spontaneously develop pancreatic ductal adenocarcinoma. In nude mice with subcutaneously implanted human Panc-1 pancreatic tumors, the antitumor activity of DHA-dFdC was significantly stronger than the molar equivalent of dFdC alone, DHA alone, or the physical mixture of them (1:1, molar ratio. DHA-dFdC also significantly inhibited the growth of Panc-1 tumors orthotopically implanted in the pancreas of nude mice, whereas the molar equivalent dose of dFdC alone did not show any significant activity. DHA-dFdC is a promising compound for the potential treatment of cancers in organs such as the pancreas.

Expression and kinetic properties of a recombinant 3 alpha-hydroxysteroid/dihydrodiol dehydrogenase isoenzyme of human liver.

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Deyashiki, Y; Tamada, Y; Miyabe, Y; Nakanishi, M; Matsuura, K; Hara, A

1995-08-01

Human liver cytosol contains multiple forms of 3 alpha-hydroxysteroid dehydrogenase and dihydrodiol dehydrogenase with hydroxysteroid dehydrogenase activity, and multiple cDNAs for the enzymes have been cloned from human liver cDNA libraries. To understand the relationship of the multiple enzyme froms to the genes, a cDNA, which has been reported to code for an isoenzyme of human liver 3 alpha-hydroxysteroid/dihydrodiol dehydrogenase, was expressed in Escherichia coli. The recombinant enzyme showed structural and functional properties almost identical to those of the isoenzyme purified from human liver. In addition, the recombinant isoenzyme efficiently reduced 5 alpha-dihydrotestosterone and 5 beta-dihydrocortisone, the known substrates of human liver 3 alpha-hydroxysteroid dehydrogenase and chlordecone reductase previously purified, which suggests that these human liver enzymes are identical. Furthermore, the steady-state kinetic data for NADP(+)-linked (S)-1-indanol oxidation by the recombinant isoenzyme were consistent with a sequential ordered mechanism in which NADP+ binds first. Phenolphthalein inhibited this isoenzyme much more potently than it did the other human liver dihydrodiol dehydrogenases, and was a competitive inhibitor (Ki = 20 nM) that bound to the enzyme-NADP+ complex.

Constitutive NADPH-dependent electron transferase activity of the Nox4 dehydrogenase domain.

Science.gov (United States)

Nisimoto, Yukio; Jackson, Heather M; Ogawa, Hisamitsu; Kawahara, Tsukasa; Lambeth, J David

2010-03-23

NADPH oxidase 4 (Nox4) is constitutively active, while Nox2 requires the cytosolic regulatory subunits p47(phox) and p67(phox) and activated Rac with activation by phorbol 12-myristate 13-acetate (PMA). This study was undertaken to identify the domain on Nox4 that confers constitutive activity. Lysates from Nox4-expressing cells exhibited constitutive NADPH- but not NADH-dependent hydrogen peroxide production with a K(m) for NADPH of 55 +/- 10 microM. The concentration of Nox4 in cell lysates was estimated using Western blotting and allowed calculation of a turnover of approximately 200 mol of H(2)O(2) min(-1) (mol of Nox4)(-1). A chimeric protein (Nox2/4) consisting of the Nox2 transmembrane (TM) domain and the Nox4 dehydrogenase (DH) domain showed H(2)O(2) production in the absence of cytosolic regulatory subunits. In contrast, chimera Nox4/2, consisting of the Nox4 TM and Nox2 DH domains, exhibited PMA-dependent activation that required coexpression of regulatory subunits. Nox DH domains from several Nox isoforms were purified and evaluated for their electron transferase activities. Nox1 DH, Nox2 DH, and Nox5 DH domains exhibited barely detectable activities toward artificial electron acceptors, while the Nox4 DH domain exhibited significant rates of reduction of cytochrome c (160 min(-1), largely superoxide dismutase-independent), ferricyanide (470 min(-1)), and other electron acceptors (artificial dyes and cytochrome b(5)). Rates were similar to those observed for H(2)O(2) production by the Nox4 holoenzyme in cell lysates. The activity required added FAD and was seen with NADPH but not NADH. These results indicate that the Nox4 DH domain exists in an intrinsically activated state and that electron transfer from NADPH to FAD is likely to be rate-limiting in the NADPH-dependent reduction of oxygen by holo-Nox4.

Design of New Antibacterial Enhancers Based on AcrB’s Structure and the Evaluation of Their Antibacterial Enhancement Activity

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Yi Song

2016-11-01

Full Text Available Previously, artesunate (AS and dihydroartemisinine 7 (DHA7 were found to have antibacterial enhancement activity against Escherichia coli via inhibition of the efflux pump AcrB. However, they were only effective against E. coli standard strains. This study aimed to develop effective antibacterial enhancers based on the previous work. Our results demonstrate that 86 new antibacterial enhancers were designed via 3D-SAR and molecular docking. Among them, DHA27 had the best antibacterial enhancement activity. It could potentiate the antibacterial effects of ampicillin against not only E. coli standard strain but also clinical strains, and of β-lactam antibiotics, not non-β-lactamantibiotics. DHA27 could increase the accumulation of daunomycin and nile red within E. coli ATCC 35218, but did not increase the bacterial membrane permeability. DHA27 reduced acrB’s mRNA expression of E. coli ATCC 35218 in a dose-dependent manner, and its antibacterial enhancement activity is related to the degree of acrB mRNA expression in E. coli clinical strains. The polypeptides from AcrB were obtained via molecular docking assay; the pre-incubated polypeptides could inhibit the activity of DHA27. Importantly, DHA27 had no cytotoxicity on cell proliferation. In conclusion, among newly designed antibacterial enhancers, DHA27 had favorable physical and pharmacological properties with no significant cytotoxicity at effective concentrations, and might serve as a potential efflux pump inhibitor in the future.

A novel 3-hydroxysteroid dehydrogenase that regulates reproductive development and longevity.

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Joshua Wollam

Full Text Available Endogenous small molecule metabolites that regulate animal longevity are emerging as a novel means to influence health and life span. In C. elegans, bile acid-like steroids called the dafachronic acids (DAs regulate developmental timing and longevity through the conserved nuclear hormone receptor DAF-12, a homolog of mammalian sterol-regulated receptors LXR and FXR. Using metabolic genetics, mass spectrometry, and biochemical approaches, we identify new activities in DA biosynthesis and characterize an evolutionarily conserved short chain dehydrogenase, DHS-16, as a novel 3-hydroxysteroid dehydrogenase. Through regulation of DA production, DHS-16 controls DAF-12 activity governing longevity in response to signals from the gonad. Our elucidation of C. elegans bile acid biosynthetic pathways reveals the possibility of novel ligands as well as striking biochemical conservation to other animals, which could illuminate new targets for manipulating longevity in metazoans.

A randomized, crossover, head-to-head comparison of eicosapentaenoic acid and docosahexaenoic acid supplementation to reduce inflammation markers in men and women: the Comparing EPA to DHA (ComparED) Study.

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Allaire, Janie; Couture, Patrick; Leclerc, Myriam; Charest, Amélie; Marin, Johanne; Lépine, Marie-Claude; Talbot, Denis; Tchernof, André; Lamarche, Benoît

2016-08-01

To date, most studies on the anti-inflammatory effects of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) in humans have used a mixture of the 2 fatty acids in various forms and proportions. We compared the effects of EPA supplementation with those of DHA supplementation (re-esterified triacylglycerol; 90% pure) on inflammation markers (primary outcome) and blood lipids (secondary outcome) in men and women at risk of cardiovascular disease. In a double-blind, randomized, crossover, controlled study, healthy men (n = 48) and women (n = 106) with abdominal obesity and low-grade systemic inflammation consumed 3 g/d of the following supplements for periods of 10 wk: 1) EPA (2.7 g/d), 2) DHA (2.7 g/d), and 3) corn oil as a control with each supplementation separated by a 9-wk washout period. Primary analyses assessed the difference in cardiometabolic outcomes between EPA and DHA. Supplementation with DHA compared with supplementation with EPA led to a greater reduction in interleukin-18 (IL-18) (-7.0% ± 2.8% compared with -0.5% ± 3.0%, respectively; P = 0.01) and a greater increase in adiponectin (3.1% ± 1.6% compared with -1.2% ± 1.7%, respectively; P DHA and EPA, changes in CRP (-7.9% ± 5.0% compared with -1.8% ± 6.5%, respectively; P = 0.25), IL-6 (-12.0% ± 7.0% compared with -13.4% ± 7.0%, respectively; P = 0.86), and tumor necrosis factor-α (-14.8% ± 5.1% compared with -7.6% ± 10.2%, respectively; P = 0.63) were NS. DHA compared with EPA led to more pronounced reductions in triglycerides (-13.3% ± 2.3% compared with -11.9% ± 2.2%, respectively; P = 0.005) and the cholesterol:HDL-cholesterol ratio (-2.5% ± 1.3% compared with 0.3% ± 1.1%, respectively; P = 0.006) and greater increases in HDL cholesterol (7.6% ± 1.4% compared with -0.7% ± 1.1%, respectively; P DHA compared with EPA was significant in men but not in women (P-treatment × sex interaction = 0.046). DHA is more effective than EPA in modulating specific markers of inflammation

Prevention and Reversal of Obesity and Glucose Intolerance in Mice by DHA Derivatives

Czech Academy of Sciences Publication Activity Database

Rossmeisl, Martin; Jeleník, Tomáš; Jílková, Zuzana; Slámová, Kristýna; Kůs, Vladimír; Hensler, Michal; Medříková, Daša; Povýšil, C.; Flachs, Pavel; Mohamed-Ali, V.; Bryhn, M.; Berge, K.; Holmeide, A.K.; Kopecký, Jan

2009-01-01

Roč. 17, č. 5 (2009), s. 1023-1031 ISSN 1930-7381 R&D Projects: GA ČR(CZ) GA303/08/0664; GA ČR(CZ) GA303/07/0708 Grant - others:EC(XE) MITOFOOD COST FA0602 Institutional research plan: CEZ:AV0Z50110509 Keywords : DHA * obesity Subject RIV: FB - Endocrinology, Diabetology, Metabolism, Nutrition Impact factor: 3.366, year: 2009

The radiation inactivation of glutamate and isocitrate dehydrogenases

International Nuclear Information System (INIS)

El Failat, R.R.A.

1980-12-01

The reaction of free radicals produced by ionizing radiation with the enzymes glutamate dehydrogenase (GDH) and NADP + -specific isocitrate dehydrogenase (ICDH) have been studied by steady-state and pulse radiolysis techniques. In de-aerated GDH solutions, hydroxyl radicals have been found to be the most efficient of the primary radicals generated from water in causing inactivation. The effect of reaction with the enzyme of selective free radicals (SCN) 2 - , (Br) 2 - and (I) 2 - on its activity has also been studied. In neutral solutions, the order of inactivating effectiveness is (I) 2 - > (Br) 2 - > (SCN) 2 - . In the case of the thiocyanate radical anion (SCN) 2 - , the inactivation efficiency is found to depend on KSCN concentration. The radiation inactivation of GDH at both neutral and alkaline pH is accompanied by the loss of sulphydryl groups. Pulse radiolysis was also used to determine the rate constants and the transient absorption spectra following the reaction of the free radicals with GDH. 60 Co-γ-radiolysis and pulse radiolysis were also used to study the effect of ionizing radiation on the activity of ICDH. The results obtained were similar to those of GDH. (author)

GOLD HULL AND INTERNODE2 encodes a primarily multifunctional cinnamyl-alcohol dehydrogenase in rice.

Science.gov (United States)

Zhang, Kewei; Qian, Qian; Huang, Zejun; Wang, Yiqin; Li, Ming; Hong, Lilan; Zeng, Dali; Gu, Minghong; Chu, Chengcai; Cheng, Zhukuan

2006-03-01

Lignin content and composition are two important agronomic traits for the utilization of agricultural residues. Rice (Oryza sativa) gold hull and internode phenotype is a classical morphological marker trait that has long been applied to breeding and genetics study. In this study, we have cloned the GOLD HULL AND INTERNODE2 (GH2) gene in rice using a map-based cloning approach. The result shows that the gh2 mutant is a lignin-deficient mutant, and GH2 encodes a cinnamyl-alcohol dehydrogenase (CAD). Consistent with this finding, extracts from roots, internodes, hulls, and panicles of the gh2 plants exhibited drastically reduced CAD activity and undetectable sinapyl alcohol dehydrogenase activity. When expressed in Escherichia coli, purified recombinant GH2 was found to exhibit strong catalytic ability toward coniferaldehyde and sinapaldehyde, while the mutant protein gh2 completely lost the corresponding CAD and sinapyl alcohol dehydrogenase activities. Further phenotypic analysis of the gh2 mutant plants revealed that the p-hydroxyphenyl, guaiacyl, and sinapyl monomers were reduced in almost the same ratio compared to the wild type. Our results suggest GH2 acts as a primarily multifunctional CAD to synthesize coniferyl and sinapyl alcohol precursors in rice lignin biosynthesis.

Dietary Intake of DHA and EPA in a Group of Pregnant Women in the Moncton Area.

Science.gov (United States)

Bishop, Nicole Arsenault; Leblanc, Caroline P

2017-06-01

To compare docosahexaenoic acid (DHA), eicosapentaenoic acid (EPA), and fish intake of pregnant women at 30 weeks of gestation to current recommendations and to determine the factors associated with omega-3 (ω-3) intake. A food frequency questionnaire was completed by 54 women (54/131 = 41%) at 30 ± 0.8 weeks gestation. Supplement intake, sociodemographic characteristics, and ω-3 food habits were evaluated. Among this high socioeconomic status (SES) group, 66.7% and 64.8% met the Food and Agriculture Organization of the United Nations (FAO)/World Health Organization (WHO) recommendation of 200 mg/d DHA and 300 mg/d DHA + EPA, respectively, and only 48.1% met the Academy of Nutrition and Dietetics (Academy) recommendation of 500 mg/d DHA + EPA. Eighteen of the 54 women took a ω-3 supplement during the third trimester. This significantly improved their total intake to meet the FAO/WHO (88.9% ≥200 mg/d DHA and 94.4% ≥300 mg/d DHA + EPA) and the Academy (77.8% ≥500 mg/d DHA + EPA) recommendations. Among nonsupplement users (36/54), 50% met the FAO/WHO recommendations and only 33.3% met the Academy recommendations. Results suggest that the majority of high SES women did not meet ω-3 recommendations from food alone. Continued prenatal education on the importance of fish intake and on the addition of ω-3 prenatal supplement is essential.

Effect of eicosapentaenoic acid/docosahexaenoic acid on coronary high-intensity plaques detected with non-contrast T1-weighted imaging (the AQUAMARINE EPA/DHA study): study protocol for a randomized controlled trial.

Science.gov (United States)

Nakao, Kazuhiro; Noguchi, Teruo; Asaumi, Yasuhide; Morita, Yoshiaki; Kanaya, Tomoaki; Fujino, Masashi; Hosoda, Hayato; Yoneda, Shuichi; Kawakami, Shoji; Nagai, Toshiyuki; Nishihira, Kensaku; Nakashima, Takahiro; Kumasaka, Reon; Arakawa, Tetsuo; Otsuka, Fumiyuki; Nakanishi, Michio; Kataoka, Yu; Tahara, Yoshio; Goto, Yoichi; Yamamoto, Haruko; Hamasaki, Toshimitsu; Yasuda, Satoshi

2018-01-08

Despite the success of HMG-CoA reductase inhibitor (statin) therapy in reducing atherosclerotic cardiovascular events, a residual risk for cardiovascular events in patients with coronary artery disease (CAD) remains. Long-chain n-3 polyunsaturated fatty acids (LC n-3 PUFAs), especially eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), are promising anti-atherosclerosis agents that might reduce the residual CAD risk. Non-contrast T1-weighted imaging (T1WI) with cardiac magnetic resonance (CMR) less invasively identifies high-risk coronary plaques as high-intensity signals. These high-intensity plaques (HIPs) are quantitatively assessed using the plaque-to-myocardium signal intensity ratio (PMR). Our goal is to assess the effect of EPA/DHA on coronary HIPs detected with T1WI in patients with CAD on statin treatment. This prospective, controlled, randomized, open-label study examines the effect of 12 months of EPA/DHA therapy and statin treatment on PMR of HIPs detected with CMR and computed tomography angiography (CTA) in patients with CAD. The primary endpoint is the change in PMR after EPA/DHA treatment. Secondary endpoints include changes in Hounsfield units, plaque volume, vessel area, and plaque area measured using CTA. Subjects are randomly assigned to either of three groups: the 2 g/day EPA/DHA group, the 4 g/day EPA/DHA group, or the no-treatment group. This trial will help assess whether EPA/DHA has an anti-atherosclerotic effect using PMR of HIPs detected by CMR. The trial outcomes will provide novel insights into the effect of EPA/DHA on high-risk coronary plaques and may provide new strategies for lowering the residual risk in patients with CAD on statin therapy. The University Hospital Medical Information Network (UMIN) Clinical Trials Registry, ID: UMIN000015316 . Registered on 2 October 2014.

The Alcohol Dehydrogenase Isoenzyme as a Potential Marker of Pancreatitis.

Science.gov (United States)

Jelski, Wojciech; Piechota, Joanna; Orywal, Karolina; Szmitkowski, Maciej

2018-05-01

Human pancreas parenchyma contains various alcohol dehydrogenase (ADH) isoenzymes and also possesses aldehyde dehydrogenase (ALDH) activity. The altered activities of ADH and ALDH in damaged pancreatic tissue in the course of pancreatitis are reflected in the human serum. The aim of this study was to investigate a potential role of ADH and ALDH as markers for acute (AP) and chronic pancreatitis (CP). Serum samples were collected for routine biochemical investigations from 75 patients suffering from acute pancreatitis and 70 patients with chronic pancreatitis. Fluorometric methods were used to measure the activity of class I and II ADH and ALDH activity. The total ADH activity and activity of class III and IV isoenzymes were measured by a photometric method. There was a significant increase in the activity of ADH III isoenzyme (15.06 mU/l and 14.62 mU/l vs. 11.82 mU/l; ppancreatitis or chronic pancreatitis compared to the control. The diagnostic sensitivity for ADH III was about 84%, specificity was 92 %, positive and negative predictive values were 93% and 87% respectively in acute pancreatitis. Area under the Receiver Operating Curve (ROC) curve for ADH III in AP and CP was 0.88 and 0.86 respectively. ADH III has a potential role as a marker of acute and chronic pancreatitis. Copyright© 2018, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.

Lactate dehydrogenase activity is inhibited by methylmalonate in vitro.