Tryptophan and Methionine Metabolism of Adult Females as Affected by Vitamin B-6 Deficiency

1974 ◽  
Vol 104 (10) ◽  
pp. 1348-1355 ◽  
Author(s):  
Heaja Kim Shin ◽  
Hellen M. Linkswiler
Keyword(s):  
Vitamin B ◽  
Methionine Metabolism ◽  
Adult Females

scholarly journals Revised D-A-CH Reference Values for the Intake of Vitamin B6

2020 ◽  
Vol 76 (4) ◽  
pp. 213-222
Author(s):  
Alexandra Jungert ◽  
Jakob Linseisen ◽  
Karl-Heinz Wagner ◽  
Margrit Richter ◽  
Keyword(s):  
Children And Adolescents ◽  
Reference Values ◽  
Coefficient Of Variation ◽  
Reference Value ◽  
First Trimester ◽  
Vitamin B ◽  
Adult Males ◽  
Allometric Exponent ◽  
Lactating Women ◽  
Adult Females

<b><i>Background:</i></b> The Nutrition Societies of Germany, Austria, and Switzerland as the joint editors of the “D-A-CH reference values for nutrient intake” have revised the reference values for vitamin B<sub>6</sub> in summer 2019. <b><i>Summary:</i></b> For women, the average requirement (AR) for vitamin B<sub>6</sub> intake was derived on the basis of balance studies using a pyridoxal-5′-phosphate (PLP) plasma concentration of ≥30 nmol/L as a biomarker of an adequate vitamin B<sub>6</sub> status. The recommended intake (RI) was derived considering a coefficient of variation of 10%. The RIs of vitamin B<sub>6</sub> for men, children, and adolescents were extrapolated from the vitamin B<sub>6</sub> requirement for women considering differences in body weight, an allometric exponent, growth factors as appropriate, and a coefficient of variation. For infants aged 0 to under 4 months, an estimated value was set based on the vitamin B<sub>6</sub> intake via breast feeding. The reference value for infants aged 4 to under 12 months was extrapolated from the estimated value for infants under 4 months of age and the average vitamin B<sub>6</sub> requirement for adults. The reference values for pregnant and lactating women consider the requirements for the foetus and the loss via breast milk. <b><i>Key Messages:</i></b> According to the combined analysis of 5 balance studies, the AR for vitamin B<sub>6</sub> to ensure a plasma PLP concentration of ≥30 nmol/L is 1.2 mg/day for adult females and the extrapolated AR for adult males is 1.3 mg/day. The corresponding RIs of vitamin B<sub>6</sub> are 1.4 mg/day for adult females and 1.6 mg/day for adult males, independent of age. For infants, the estimated value is 0.1 mg/day and 0.3 mg/day, depending on age. The AR of vitamin B<sub>6</sub> for children and adolescents ranges between 0.5 and 1.5 mg/day, and the RI is between 0.6 mg/day and 1.6 mg/day. During pregnancy, the AR is 1.3 mg/day in the first trimester and 1.5 mg/day in the second and third trimesters; the RI is 1.5 mg/day in the first trimester and 1.8 mg/day in the second and third trimesters. For lactating women, the AR is 1.3 mg/day and the RI is 1.6 mg/day.

scholarly journals Elucidation of roles for vitamin B12 in regulation of folate, ubiquinone, and methionine metabolism

2017 ◽  
Vol 114 (7) ◽  
pp. E1205-E1214 ◽  
Author(s):  
Margaret F. Romine ◽  
Dmitry A. Rodionov ◽  
Yukari Maezato ◽  
Lindsey N. Anderson ◽  
Premchendar Nandhikonda ◽  
...  
Keyword(s):  
Vitamin B12 ◽  
Microbial Communities ◽  
Binding Proteins ◽  
De Novo ◽  
Transcriptional Regulator ◽  
Vitamin B ◽  
Methionine Metabolism ◽  
Community Metabolism ◽  
Light Sensing ◽  
Allosteric Effector

Only a small fraction of vitamin B12-requiring organisms are able to synthesize B12 de novo, making it a common commodity in microbial communities. Initially recognized as an enzyme cofactor of a few enzymes, recent studies have revealed additional B12-binding enzymes and regulatory roles for B12. Here we report the development and use of a B12-based chemical probe to identify B12-binding proteins in a nonphototrophic B12-producing bacterium. Two unexpected discoveries resulted from this study. First, we identified a light-sensing B12-binding transcriptional regulator and demonstrated that it controls folate and ubiquinone biosynthesis. Second, our probe captured proteins involved in folate, methionine, and ubiquinone metabolism, suggesting that it may play a role as an allosteric effector of these processes. These metabolic processes produce precursors for synthesis of DNA, RNA, and protein. Thereby, B12 likely modulates growth, and by limiting its availability to auxotrophs, B12-producing organisms may facilitate coordination of community metabolism.

SOME OBSERVATIONS ON THE RELATIONSHIP BETWEEN VITAMIN B12 AND REPRODUCTION IN SWINE

1961 ◽  
Vol 41 (2) ◽  
pp. 212-219 ◽  
Author(s):  
G. L. Frederick ◽  
G. J. Brisson
Keyword(s):  
Dietary Intake ◽  
Vitamin B12 ◽  
Serum Vitamin ◽  
Dietary Vitamin ◽  
Vitamin B ◽  
Milk Diet ◽  
Feed Conversion ◽  
Deficient Diet ◽  
Adult Females ◽  
The Relationship

Six female swine were maintained during one or more gestations on a vitamin B12-deficient diet. Two that had been fed the deficient diet for more than 2 years prior to their first gestation aborted. Four that received the deficient diet for 7 months prior to their first gestation farrowed a total of 8 litters containing 68 live piglets; 27 died within 3 days. All piglets fed a synthetic milk diet, deficient in vitamin B12, died within 14 days.Five adult females fed the deficient diet supplemented with 400 μg. of vitamin B12 per animal per day farrowed a total of 8 litters containing 83 live piglets; none died within 3 days. Of 14 piglets fed a vitamin B12-deficient synthetic milk diet, 2 died within 14 days.The different dietary vitamin B12 intakes of the adults influenced the serum vitamin B12 levels of the adults and of their offspring.Piglets fed vitamin B12 gained more, but feed conversion was not influenced by the vitamin B12 dietary intake of the piglets or by the intake of their dams during gestation.It is concluded that vitamin B12 influences swine reproduction and neonatal survival.

scholarly journals Genetic Influences of the Microbiota on the Life Span of Drosophila melanogaster

2020 ◽  
Vol 86 (10) ◽  
Author(s):  
Melinda K. Matthews ◽  
Hailey Wilcox ◽  
Rachel Hughes ◽  
Madeline Veloz ◽  
Austin Hammer ◽  
...  
Keyword(s):  
Drosophila Melanogaster ◽  
Life Span ◽  
Fruit Fly ◽  
Vitamin B ◽  
Methionine Metabolism ◽  
Content Type ◽  
Methionine Restriction ◽  
Host Life ◽  
Bacterial Genes

ABSTRACT To better understand how associated microorganisms (“microbiota”) influence organismal aging, we focused on the model organism Drosophila melanogaster. We conducted a metagenome-wide association (MGWA) as a screen to identify bacterial genes associated with variation in the D. melanogaster life span. The results of the MGWA predicted that bacterial cysteine and methionine metabolism genes influence fruit fly longevity. A mutant analysis, in which flies were inoculated with Escherichia coli strains bearing mutations in various methionine cycle genes, confirmed a role for some methionine cycle genes in extending or shortening fruit fly life span. Initially, we predicted these genes might influence longevity by mimicking or opposing methionine restriction, an established mechanism for life span extension in fruit flies. However, follow-up transcriptome sequencing (RNA-seq) and metabolomic experiments were generally inconsistent with this conclusion and instead implicated glucose and vitamin B6 metabolism in these influences. We then tested if bacteria could influence life span through methionine restriction using a different set of bacterial strains. Flies reared with a bacterial strain that ectopically expressed bacterial transsulfuration genes and lowered the methionine content of the fly diet also extended female D. melanogaster life span. Taken together, the microbial influences shown here overlap with established host genetic mechanisms for aging and therefore suggest overlapping roles for host and microbial metabolism genes in organismal aging. IMPORTANCE Associated microorganisms (“microbiota”) are intimately connected to the behavior and physiology of their animal hosts, and defining the mechanisms of these interactions is an urgent imperative. This study focuses on how microorganisms influence the life span of a model host, the fruit fly Drosophila melanogaster. First, we performed a screen that suggested a strong influence of bacterial methionine metabolism on host life span. Follow-up analyses of gene expression and metabolite abundance identified stronger roles for vitamin B6 and glucose than methionine metabolism among the tested mutants, possibly suggesting a more limited role for bacterial methionine metabolism genes in host life span effects. In a parallel set of experiments, we created a distinct bacterial strain that expressed life span-extending methionine metabolism genes and showed that this strain can extend fly life span. Therefore, this work identifies specific bacterial genes that influence host life span, including in ways that are consistent with the expectations of methionine restriction.

Homocysteine and Cardiovascular Disease: Interactions Between Nutrition, Genetics and Lifestyle

2004 ◽  
Vol 29 (6) ◽  
pp. 773-780 ◽  
Author(s):  
John T. Brosnan
Keyword(s):  
Cardiovascular Disease ◽  
Folic Acid ◽  
Renal Disease ◽  
Methylenetetrahydrofolate Reductase ◽  
Coffee Consumption ◽  
Plasma Homocysteine ◽  
Folate Intake ◽  
Vitamin B ◽  
Methionine Metabolism ◽  
Vitamin Deficiencies

Homocysteine is a sulfur-containing amino acid that arises during methionine metabolism. Although its concentration in plasma is only about 10 micromolar, even moderate hyperhomocysteinemia is associated with increased incidence of cardiovascular disease and Alzheimer's disease. Elevations in plasma homocysteine are commonly found as a result of vitamin deficiencies, polymorphisms of enzymes of methionine metabolism, and renal disease. Pyridoxal, folic acid, riboflavin, and Vitamin B12 are all required for methionine metabolism, and deficiences of each of these vitamins result in elevated plasma homocysteine. A polymorphism of methylenetetrahydrofolate reductase (C677T), which is quite common in most populations with a homozygosity rate of 10-15%, is associated with moderate hyperhomocysteinemia, especially in the context of marginal folate intake. Plasma homocysteine is inversely related to plasma creatinine in patients with renal disease. This is due to an impairment in homocysteine removal in renal disease. The role of these factors, and of modifiable life style factors, in affecting methionone metabolism and in determining plasma homocysteine levels is discussed. Key words: methionine, liver metabolism, folic acid, vitamin B12, polymorphisms, neural tube defects, end-stage renal disease, coffee consumption

scholarly journals Genetics of hyperhomocysteinaemia in cardiovascular disease

2003 ◽  
Vol 40 (1) ◽  
pp. 46-59 ◽  
Author(s):  
Karin J.A. Lievers ◽  
Leo A.J. Kluijtmans ◽  
Henk J. Blom
Keyword(s):  
Cardiovascular Disease ◽  
High Plasma ◽  
Plasma Homocysteine ◽  
Genetic Defects ◽  
Vitamin B ◽  
Methionine Metabolism ◽  
Elevated Plasma ◽  
Genetic Determinants ◽  
Genes Encoding ◽  
Very High

Homocysteine, a sulphur amino acid, is a branch-point intermediate of methionine metabolism. It can be degraded in the transsulphuration pathway to cystathionine, or remethylated to methionine via the remethylation pathway. In both pathways, major genetic defects that cause enzyme deficiencies are associated with very high plasma homocysteine concentrations and excretion of homocystine into the urine. Mildly elevated plasma homocysteine concentrations are thought to be an independent and graded risk factor for both arterial occlusive disease and venous thrombosis. Genetic defects in genes encoding enzymes involved in homocysteine metabolism, or depletion of important cofactors or (co)substrates for those enzymes, including folate, vitamin B12 and vitamin B6, may result in elevated plasma homocysteine concentrations. Plasma homocysteine concentrations are also influenced by dietary and lifestyle factors. In the last decade, several studies have been conducted to elucidate the genetic determinants of hyperhomocysteinaemia in patients with cardiovascular disease. We report on both environmental and genetic determinants of hyperhomocysteinaemia and give a detailed overview of all the genetic determinants that have been reported to date.

Schutz vor Insekten

2005 ◽  
Vol 62 (11) ◽  
pp. 713-718 ◽  
Author(s):  
Rudin
Keyword(s):  
Vitamin B ◽  
Eucalyptus Citriodora ◽  
Knock Down

Erfolgreicher Schutz gegen Stiche von blutsaugenden Insekten und Zecken bedingt die konsequente Anwendung geeigneter Maßnahmen. Eine eventuell notwendige Chemoprophylaxe wird dadurch nie ersetzt. Die Umstände, unter denen der Schutz erreicht werden soll, bestimmen die Kombination der zu treffenden Maßnahmen. Von Wohnräumen kann man Insekten mit Mückengittern oder -gaze an Fenstern und Türen oder mittels Klimaanlagen fernhalten. Beim Schlafen kann man sich mit einem Moskitonetz schützen. Diese Maßnahmen können bei Bedarf durch Insektizide ergänzt oder unterstützt werden. Meistens kommen synthetische Pyrethroide entweder als «knock down»-Sprays oder elektroverdampft für die Behandlung von Räumen oder als Imprägnierungsmittel von Netzen und Gittern zum Einsatz. Wenn ein Kontakt nicht durch die Wahl von Aufenthaltsort und -zeit vermeidbar ist, werden außer Haus zum Schutz vor Stichen geeignete Kleidung sowie Repellentien eingesetzt. Kleider sollen möglichst viel Körperfläche bedecken, aus festem Gewebe, nicht eng anliegend und von heller Farbe sein. Eine zusätzliche Behandlung mit Insektiziden ist vorteilhaft. Repellentien werden direkt auf die Haut appliziert. Diethylmethylbenzamin (DEET) zeigt seit vielen Jahren eine verlässliche Wirkung. Ebenfalls verbreitete synthetische Wirkstoffe sind Bayrepel® und IR3535. Sie weisen ein noch etwas geringeres Nebenwirkungsrisiko auf, nachteilig ist jedoch die schwächere Wirkung. Von den pflanzlichen Produkten sind die mit einem Extrakt aus Eucalyptus citriodora die am besten wirksamen. Schwächere Produkte schützen Personen, die für Mücken speziell attraktiv sind, nur ungenügend. Völlig nutzlos sind auf Arm-, Halsbänder oder Kleber aufgetragene Repellentien, sowie Ultraschallgeräte, UV-Lichtfallen oder die Einnahme von Vitamin B1 oder Knoblauch.

Nutritional B12 Deficiency in Infants of Vitamin B12-Deficient Mothers

2011 ◽  
Vol 81 (5) ◽  
pp. 328-334 ◽  
Author(s):  
Oya Halicioglu ◽  
Sezin Asik Akman ◽  
Sumer Sutcuoglu ◽  
Berna Atabay ◽  
Meral Turker ◽  
...  
Keyword(s):  
Megaloblastic Anemia ◽  
Maternal Diet ◽  
Clinical Manifestations ◽  
Serum Vitamin ◽  
Failure To Thrive ◽  
Clinical Findings ◽  
Vitamin B ◽  
Animal Products ◽  
Hematological Evaluation ◽  
Nutritional Vitamin

Aim: Nutritional vitamin B12 deficiency in infants may occur because the maternal diet contains inadequate animal products. Clinical presentations of the infants who had nutritional vitamin B12 deficiency were analyzed in this study. Subjects and Methods: Patients with nutritional vitamin B12 deficiency were enrolled in the study between 2003 and 2010. The diagnosis was based on a nutritional history of mothers and infants, clinical findings, hematological evaluation, and low level of serum vitamin B12. Results: Thirty children aged 1 - 21 months constituted the study group. Poverty was the main cause of inadequate consumption of animal products of the mothers. All infants had predominantly breastfed. The most common symptoms were developmental delay, paleness, apathy, lethargy, anorexia, and failure to thrive. Hematological findings were megaloblastic anemia (83.3 %), thrombocytopenia (30 %), and severe anemia (13.3 %). All of the mothers had low serum B12 levels; eight of them had megaloblastic anemia. Conclusion: The unusual clinical manifestations of vitamin B12 deficiency may also be seen apart from neurological and hematological findings. Nutritional vitamin B12 deficiency due to maternal deficiency might be a serious health problem in infants. Therefore, screening and supplementation of pregnant and lactating women to prevent infantile vitamin B12 deficiency should be considered.

Vitamin B6 Deficiency can Reduce Fuel Storage and Utilization in Physically Trained Rats

2008 ◽  
Vol 78 (2) ◽  
pp. 64-69 ◽  
Author(s):  
Choi ◽  
Cho
Keyword(s):  
Skeletal Muscle ◽  
Fatty Acid ◽  
Muscle Protein ◽  
Plasma Free Fatty Acid ◽  
Vitamin B ◽  
Liver Protein ◽  
Protein Levels ◽  
Before And After ◽  
Fuel Storage ◽  
Exercise Muscle

This study investigated the effect of vitamin B6 deficiency on the utilization and recuperation of stored fuel in physically trained rats. 48 rats were given either vitamin B6-deficient (B6–) diet or control (B6+) diet for 4 weeks and were trained on treadmill for 30 minutes daily. All animals were then subdivided into 3 groups: before-exercise (BE); during-exercise (DE); after-exercise (AE). The DE group was exercised on treadmill for 1 hour just before being sacrificed. Animals in the AE group were allowed to take a rest for 2 hours after being exercised like the DE group. Glucose and free fatty acids were compared in plasma. Glycogen and triglyceride were compared in liver and skeletal muscle. Protein levels were compared in plasma, liver, and skeletal muscle. Compared with the B6+ group, plasma glucose levels of the B6– group were significantly lower before and after exercise. Muscle glycogen levels of the B6– group were significantly lower than those of the B6+ group regardless of exercise. The liver glycogen level of the B6– group was also significantly lower than that of B6+ group during and after exercise. Before exercise, plasma free fatty acid levels were not significantly different between the B6+ and B6– groups, and plasma free fatty acid levels of the B6– group were significantly lower during and after exercise. The muscle triglyceride level of the B6– group was significantly lower than that of the B6+ group before exercise, and there were no differences between B6+ and B6– groups during and after exercise. Liver triglyceride levels were not significantly different between B6+ and B6– groups. Plasma protein levels of the B6– group were lower than those of B6+ before and after exercise. Muscle protein levels of the B6– group were not significantly different from those of the B6+ group. Liver protein levels of the B6– group were significantly lower than that of the B6+ group after exercise. Liver protein levels of both B6+ and B6– groups were not significantly changed, regardless of exercise. Thus, it is suggested that vitamin B6 deficiency may reduce fuel storage and utilization with exercise in physically trained rats.

Homocysteine Levels Show Significant Differences among Mediterranean Dietary Quality Index Variables Compared to Folate and Vitamin B12 Status in Women

2015 ◽  
Vol 85 (3-4) ◽  
pp. 202-210 ◽  
Author(s):  
Ivona Višekruna ◽  
Ivana Rumbak ◽  
Ivana Rumora Samarin ◽  
Irena Keser ◽  
Jasmina Ranilović
Keyword(s):  
Mediterranean Diet ◽  
Diet Quality ◽  
Quality Index ◽  
Fruits And Vegetables ◽  
Reproductive Age ◽  
Dietary Quality ◽  
Vitamin B ◽  
Cross Sectional ◽  
Poor Diet ◽  
The Mediterranean

Abstract. Results of epidemiologic studies and clinical trials have shown that subjects following the Mediterranean diet had lower inflammatory markers such as homocysteine (Hcy). Therefore, the aim of this cross-sectional study was to assess female diet quality with the Mediterranean diet quality index (MDQI) and to determine the correlation between MDQI, homocysteine, folate and vitamin B12 levels in the blood. The study participants were 237 apparently healthy women (96 of reproductive age and 141 postmenopausal) between 25 and 93 years. For each participant, 24-hour dietary recalls for 3 days were collected, MDQI was calculated, and plasma Hcy, serum and erythrocyte folate and vitamin B12 levels were analysed. Total MDQI ranged from 8 to 10 points, which represented a medium-poor diet for the subjects. The strength of correlation using biomarkers, regardless of group type, age, gender and other measured parameters, was ranked from best (0.11) to worst (0.52) for olive oil, fish, fruits and vegetables, grains, and meat, in this order. Hcy levels showed the best response among all markers across all groups and food types. Our study shows significant differences between variables of the MDQI and Hcy levels compared to levels of folate and vitamin B12 in participants with medium-poor diet quality, as evaluated according to MDQI scores.

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