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Stephen T Chambers - One of the best experts on this subject based on the ideXlab platform.
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is n n Dimethylglycine n oxide a choline and betaine metabolite
Biological Chemistry, 2017Co-Authors: Michael Lever, Peter M George, Christopher J Mcentyre, Stephen T ChambersAbstract:Abstract Choline metabolism is by oxidation to betaine, which is demethylated to N,N-Dimethylglycine; Dimethylglycine is oxidatively demethylated to sarcosine. This pathway is important for osmoregulation and as a source of methyl groups. We asked whether another metabolite was involved. We synthesized the N-oxide of Dimethylglycine (DMGO) by oxidizing Dimethylglycine with peracetic acid, and measured DMGO in human plasma and urine by HPLC-MS/MS with positive ion detection, using two chromatography procedures, based on ion exchange and HILIC separations. The molecular ion DMGOH+ (m/z=120) yielded four significant fragments (m/z=103, 102, 58 and 42). The suspected DMGO peak in human body fluids showed all these fragments, and co-chromatographed with added standard DMGO in both HPLC systems. Typical plasma concentrations of DMGO are under 1 μmol/l. They may be lower in metabolic syndrome patients. Urine concentrations are higher, and DMGO has a higher fractional clearance than Dimethylglycine, betaine and choline. It was present in all of over 80 human urine and plasma samples assayed. Plasma DMGO concentrations correlate with plasma DMG concentrations, with betaine and choline concentrations, with the osmolyte myo-inositol, and strongly with urinary DMGO excretion. We conclude that DMGO is probably a normal human metabolite.
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plasma and urine betaine and Dimethylglycine variation in healthy young male subjects
Clinical Biochemistry, 2009Co-Authors: Michael Lever, Wendy Atkinson, Sandy Slow, Stephen T Chambers, Peter M GeorgeAbstract:Objectives We aimed to compare the individuality (within subject consistency) of plasma and urine betaine and N,N-Dimethylglycine. Design and methods In two separate groups of 8 males (ages 19 to 40), plasma (10) and urine (6) samples were collected either over a single day or over an 8 week period. The individuality of the betaine and N,N-Dimethylglycine plasma concentrations and excretions were estimated by one-way repeated measures analysis of variance. The reliability coefficients and indices of individuality were calculated. The between-subject variation in the study population was compared with that in a normal population (n = 192 for plasma, 205 for urine). Results Plasma betaine concentrations were significantly different between subjects over 24 h and 8 weeks (p < 0.00001). Plasma Dimethylglycine concentrations were different over 24 h. Urine betaine and Dimethylglycine excretions were different in both (p < 0.0001). Betaine was more individual than Dimethylglycine in both plasma and urine. Compared with a normal healthy population, the between-subject variation in plasma betaine was less (p < 0.001) in the study group, but similar for Dimethylglycine and for urine betaine. Conclusions Plasma betaine and urinary betaine excretions are more individual than Dimethylglycine. Plasma and urine betaine are highly individual in the general population.
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Plasma and urine betaine and Dimethylglycine variation in healthy young male subjects.
Clinical Biochemistry, 2009Co-Authors: Michael Lever, Wendy Atkinson, Sandy Slow, Stephen T Chambers, Peter M GeorgeAbstract:Objectives We aimed to compare the individuality (within subject consistency) of plasma and urine betaine and N,N-Dimethylglycine. Design and methods In two separate groups of 8 males (ages 19 to 40), plasma (10) and urine (6) samples were collected either over a single day or over an 8 week period. The individuality of the betaine and N,N-Dimethylglycine plasma concentrations and excretions were estimated by one-way repeated measures analysis of variance. The reliability coefficients and indices of individuality were calculated. The between-subject variation in the study population was compared with that in a normal population (n = 192 for plasma, 205 for urine). Results Plasma betaine concentrations were significantly different between subjects over 24 h and 8 weeks (p
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Plasma and urine betaine and Dimethylglycine variation in healthy young male subjects.
Clinical biochemistry, 2009Co-Authors: Michael Lever, Wendy Atkinson, Sandy Slow, Stephen T Chambers, Peter M GeorgeAbstract:We aimed to compare the individuality (within subject consistency) of plasma and urine betaine and N,N-Dimethylglycine. In two separate groups of 8 males (ages 19 to 40), plasma (10) and urine (6) samples were collected either over a single day or over an 8 week period. The individuality of the betaine and N,N-Dimethylglycine plasma concentrations and excretions were estimated by one-way repeated measures analysis of variance. The reliability coefficients and indices of individuality were calculated. The between-subject variation in the study population was compared with that in a normal population (n=192 for plasma, 205 for urine). Plasma betaine concentrations were significantly different between subjects over 24 h and 8 weeks (p<0.00001). Plasma Dimethylglycine concentrations were different over 24 h. Urine betaine and Dimethylglycine excretions were different in both (p<0.0001). Betaine was more individual than Dimethylglycine in both plasma and urine. Compared with a normal healthy population, the between-subject variation in plasma betaine was less (p<0.001) in the study group, but similar for Dimethylglycine and for urine betaine. Plasma betaine and urinary betaine excretions are more individual than Dimethylglycine. Plasma and urine betaine are highly individual in the general population.
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Dimethylglycine supplementation does not affect plasma homocysteine concentrations in pre dialysis chronic renal failure patients
Clinical Biochemistry, 2004Co-Authors: Sandy Slow, Michael Lever, Stephen T Chambers, Peter M George, David O McgregorAbstract:Abstract Objective: To determine whether daily Dimethylglycine supplementation affects plasma homocysteine concentrations. Design and methods: A randomized, blinded, crossover design was used. Seven pre-dialysis chronic renal failure patients consumed 400 mg of Dimethylglycine or placebo daily for 28 days. Fasting blood samples and 12-h urine samples were collected at baseline and at the end of each treatment period for analysis. Results: No significant differences were observed in plasma homocysteine ( P = 0.624), glycine betaine ( P = 0.452) and methionine ( P = 0.457) concentrations between Dimethylglycine and placebo treatments. Conclusion: Daily supplementation with Dimethylglycine does not affect plasma homocysteine.
Michael Lever - One of the best experts on this subject based on the ideXlab platform.
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is n n Dimethylglycine n oxide a choline and betaine metabolite
Biological Chemistry, 2017Co-Authors: Michael Lever, Peter M George, Christopher J Mcentyre, Stephen T ChambersAbstract:Abstract Choline metabolism is by oxidation to betaine, which is demethylated to N,N-Dimethylglycine; Dimethylglycine is oxidatively demethylated to sarcosine. This pathway is important for osmoregulation and as a source of methyl groups. We asked whether another metabolite was involved. We synthesized the N-oxide of Dimethylglycine (DMGO) by oxidizing Dimethylglycine with peracetic acid, and measured DMGO in human plasma and urine by HPLC-MS/MS with positive ion detection, using two chromatography procedures, based on ion exchange and HILIC separations. The molecular ion DMGOH+ (m/z=120) yielded four significant fragments (m/z=103, 102, 58 and 42). The suspected DMGO peak in human body fluids showed all these fragments, and co-chromatographed with added standard DMGO in both HPLC systems. Typical plasma concentrations of DMGO are under 1 μmol/l. They may be lower in metabolic syndrome patients. Urine concentrations are higher, and DMGO has a higher fractional clearance than Dimethylglycine, betaine and choline. It was present in all of over 80 human urine and plasma samples assayed. Plasma DMGO concentrations correlate with plasma DMG concentrations, with betaine and choline concentrations, with the osmolyte myo-inositol, and strongly with urinary DMGO excretion. We conclude that DMGO is probably a normal human metabolite.
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the clinical significance of betaine an osmolyte with a key role in methyl group metabolism
Clinical Biochemistry, 2010Co-Authors: Michael Lever, Sandy SlowAbstract:Betaine is an essential osmolyte and source of methyl groups and comes from either the diet or by the oxidation of choline. Its metabolism methylates homocysteine to methionine, also producing N,N-Dimethylglycine. Betaine insufficiency is associated with the metabolic syndrome, lipid disorders and diabetes, and may have a role in vascular and other diseases. Betaine is important in development, from the pre-implantation embryo to infancy. Betaine supplementation improves animal and poultry health, but the effect of long-term supplementation on humans is not known, though reports that it improves athletic performance will stimulate further studies. Subsets of the population that may benefit from betaine supplementation could be identified by the laboratory, in particular those who excessively lose betaine through the urine. Plasma betaine is highly individual, in women typically 20–60 μmol/L and in men 25–75 μmol/L. Plasma Dimethylglycine is typically < 10 μmol/L. Urine betaine excretion is minimal, even following a large betaine dose. It is constant, highly individual and normally < 35 mmol/mole creatinine. The preferred method of betaine measurement is by LC-MS/MS, which is rapid and capable of automation. Slower HPLC methods give comparable results. Proton NMR spectrometry is another option but caution is needed to avoid confusion with trimethylamine-N-oxide.
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plasma and urine betaine and Dimethylglycine variation in healthy young male subjects
Clinical Biochemistry, 2009Co-Authors: Michael Lever, Wendy Atkinson, Sandy Slow, Stephen T Chambers, Peter M GeorgeAbstract:Objectives We aimed to compare the individuality (within subject consistency) of plasma and urine betaine and N,N-Dimethylglycine. Design and methods In two separate groups of 8 males (ages 19 to 40), plasma (10) and urine (6) samples were collected either over a single day or over an 8 week period. The individuality of the betaine and N,N-Dimethylglycine plasma concentrations and excretions were estimated by one-way repeated measures analysis of variance. The reliability coefficients and indices of individuality were calculated. The between-subject variation in the study population was compared with that in a normal population (n = 192 for plasma, 205 for urine). Results Plasma betaine concentrations were significantly different between subjects over 24 h and 8 weeks (p < 0.00001). Plasma Dimethylglycine concentrations were different over 24 h. Urine betaine and Dimethylglycine excretions were different in both (p < 0.0001). Betaine was more individual than Dimethylglycine in both plasma and urine. Compared with a normal healthy population, the between-subject variation in plasma betaine was less (p < 0.001) in the study group, but similar for Dimethylglycine and for urine betaine. Conclusions Plasma betaine and urinary betaine excretions are more individual than Dimethylglycine. Plasma and urine betaine are highly individual in the general population.
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Plasma and urine betaine and Dimethylglycine variation in healthy young male subjects.
Clinical Biochemistry, 2009Co-Authors: Michael Lever, Wendy Atkinson, Sandy Slow, Stephen T Chambers, Peter M GeorgeAbstract:Objectives We aimed to compare the individuality (within subject consistency) of plasma and urine betaine and N,N-Dimethylglycine. Design and methods In two separate groups of 8 males (ages 19 to 40), plasma (10) and urine (6) samples were collected either over a single day or over an 8 week period. The individuality of the betaine and N,N-Dimethylglycine plasma concentrations and excretions were estimated by one-way repeated measures analysis of variance. The reliability coefficients and indices of individuality were calculated. The between-subject variation in the study population was compared with that in a normal population (n = 192 for plasma, 205 for urine). Results Plasma betaine concentrations were significantly different between subjects over 24 h and 8 weeks (p
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Plasma and urine betaine and Dimethylglycine variation in healthy young male subjects.
Clinical biochemistry, 2009Co-Authors: Michael Lever, Wendy Atkinson, Sandy Slow, Stephen T Chambers, Peter M GeorgeAbstract:We aimed to compare the individuality (within subject consistency) of plasma and urine betaine and N,N-Dimethylglycine. In two separate groups of 8 males (ages 19 to 40), plasma (10) and urine (6) samples were collected either over a single day or over an 8 week period. The individuality of the betaine and N,N-Dimethylglycine plasma concentrations and excretions were estimated by one-way repeated measures analysis of variance. The reliability coefficients and indices of individuality were calculated. The between-subject variation in the study population was compared with that in a normal population (n=192 for plasma, 205 for urine). Plasma betaine concentrations were significantly different between subjects over 24 h and 8 weeks (p<0.00001). Plasma Dimethylglycine concentrations were different over 24 h. Urine betaine and Dimethylglycine excretions were different in both (p<0.0001). Betaine was more individual than Dimethylglycine in both plasma and urine. Compared with a normal healthy population, the between-subject variation in plasma betaine was less (p<0.001) in the study group, but similar for Dimethylglycine and for urine betaine. Plasma betaine and urinary betaine excretions are more individual than Dimethylglycine. Plasma and urine betaine are highly individual in the general population.
Peter M George - One of the best experts on this subject based on the ideXlab platform.
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is n n Dimethylglycine n oxide a choline and betaine metabolite
Biological Chemistry, 2017Co-Authors: Michael Lever, Peter M George, Christopher J Mcentyre, Stephen T ChambersAbstract:Abstract Choline metabolism is by oxidation to betaine, which is demethylated to N,N-Dimethylglycine; Dimethylglycine is oxidatively demethylated to sarcosine. This pathway is important for osmoregulation and as a source of methyl groups. We asked whether another metabolite was involved. We synthesized the N-oxide of Dimethylglycine (DMGO) by oxidizing Dimethylglycine with peracetic acid, and measured DMGO in human plasma and urine by HPLC-MS/MS with positive ion detection, using two chromatography procedures, based on ion exchange and HILIC separations. The molecular ion DMGOH+ (m/z=120) yielded four significant fragments (m/z=103, 102, 58 and 42). The suspected DMGO peak in human body fluids showed all these fragments, and co-chromatographed with added standard DMGO in both HPLC systems. Typical plasma concentrations of DMGO are under 1 μmol/l. They may be lower in metabolic syndrome patients. Urine concentrations are higher, and DMGO has a higher fractional clearance than Dimethylglycine, betaine and choline. It was present in all of over 80 human urine and plasma samples assayed. Plasma DMGO concentrations correlate with plasma DMG concentrations, with betaine and choline concentrations, with the osmolyte myo-inositol, and strongly with urinary DMGO excretion. We conclude that DMGO is probably a normal human metabolite.
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plasma and urine betaine and Dimethylglycine variation in healthy young male subjects
Clinical Biochemistry, 2009Co-Authors: Michael Lever, Wendy Atkinson, Sandy Slow, Stephen T Chambers, Peter M GeorgeAbstract:Objectives We aimed to compare the individuality (within subject consistency) of plasma and urine betaine and N,N-Dimethylglycine. Design and methods In two separate groups of 8 males (ages 19 to 40), plasma (10) and urine (6) samples were collected either over a single day or over an 8 week period. The individuality of the betaine and N,N-Dimethylglycine plasma concentrations and excretions were estimated by one-way repeated measures analysis of variance. The reliability coefficients and indices of individuality were calculated. The between-subject variation in the study population was compared with that in a normal population (n = 192 for plasma, 205 for urine). Results Plasma betaine concentrations were significantly different between subjects over 24 h and 8 weeks (p < 0.00001). Plasma Dimethylglycine concentrations were different over 24 h. Urine betaine and Dimethylglycine excretions were different in both (p < 0.0001). Betaine was more individual than Dimethylglycine in both plasma and urine. Compared with a normal healthy population, the between-subject variation in plasma betaine was less (p < 0.001) in the study group, but similar for Dimethylglycine and for urine betaine. Conclusions Plasma betaine and urinary betaine excretions are more individual than Dimethylglycine. Plasma and urine betaine are highly individual in the general population.
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Plasma and urine betaine and Dimethylglycine variation in healthy young male subjects.
Clinical Biochemistry, 2009Co-Authors: Michael Lever, Wendy Atkinson, Sandy Slow, Stephen T Chambers, Peter M GeorgeAbstract:Objectives We aimed to compare the individuality (within subject consistency) of plasma and urine betaine and N,N-Dimethylglycine. Design and methods In two separate groups of 8 males (ages 19 to 40), plasma (10) and urine (6) samples were collected either over a single day or over an 8 week period. The individuality of the betaine and N,N-Dimethylglycine plasma concentrations and excretions were estimated by one-way repeated measures analysis of variance. The reliability coefficients and indices of individuality were calculated. The between-subject variation in the study population was compared with that in a normal population (n = 192 for plasma, 205 for urine). Results Plasma betaine concentrations were significantly different between subjects over 24 h and 8 weeks (p
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Plasma and urine betaine and Dimethylglycine variation in healthy young male subjects.
Clinical biochemistry, 2009Co-Authors: Michael Lever, Wendy Atkinson, Sandy Slow, Stephen T Chambers, Peter M GeorgeAbstract:We aimed to compare the individuality (within subject consistency) of plasma and urine betaine and N,N-Dimethylglycine. In two separate groups of 8 males (ages 19 to 40), plasma (10) and urine (6) samples were collected either over a single day or over an 8 week period. The individuality of the betaine and N,N-Dimethylglycine plasma concentrations and excretions were estimated by one-way repeated measures analysis of variance. The reliability coefficients and indices of individuality were calculated. The between-subject variation in the study population was compared with that in a normal population (n=192 for plasma, 205 for urine). Plasma betaine concentrations were significantly different between subjects over 24 h and 8 weeks (p<0.00001). Plasma Dimethylglycine concentrations were different over 24 h. Urine betaine and Dimethylglycine excretions were different in both (p<0.0001). Betaine was more individual than Dimethylglycine in both plasma and urine. Compared with a normal healthy population, the between-subject variation in plasma betaine was less (p<0.001) in the study group, but similar for Dimethylglycine and for urine betaine. Plasma betaine and urinary betaine excretions are more individual than Dimethylglycine. Plasma and urine betaine are highly individual in the general population.
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Dimethylglycine supplementation does not affect plasma homocysteine concentrations in pre dialysis chronic renal failure patients
Clinical Biochemistry, 2004Co-Authors: Sandy Slow, Michael Lever, Stephen T Chambers, Peter M George, David O McgregorAbstract:Abstract Objective: To determine whether daily Dimethylglycine supplementation affects plasma homocysteine concentrations. Design and methods: A randomized, blinded, crossover design was used. Seven pre-dialysis chronic renal failure patients consumed 400 mg of Dimethylglycine or placebo daily for 28 days. Fasting blood samples and 12-h urine samples were collected at baseline and at the end of each treatment period for analysis. Results: No significant differences were observed in plasma homocysteine ( P = 0.624), glycine betaine ( P = 0.452) and methionine ( P = 0.457) concentrations between Dimethylglycine and placebo treatments. Conclusion: Daily supplementation with Dimethylglycine does not affect plasma homocysteine.
Jerry Vockley - One of the best experts on this subject based on the ideXlab platform.
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mammalian electron transferring flavoprotein flavoprotein dehydrogenase complexes observed by microelectrospray ionization mass spectrometry and surface plasmon resonance
Journal of Biological Chemistry, 2004Co-Authors: Heidi M Hoardfruchey, Linda Benson, Stephen Naylor, Eric S Goetzman, Jerry VockleyAbstract:Abstract Microelectrospray ionization-mass spectrometry was used to directly observe electron transferring flavoprotein·flavoprotein dehydrogenase interactions. When electron transferring flavoprotein and porcine Dimethylglycine dehydrogenase or sarcosine dehydrogenase were incubated together in the absence of substrate, a relative molecular mass corresponding to the flavoprotein·electron transferring flavoprotein complex was observed, providing the first direct observation of these mammalian complexes. When an acyl-CoA dehydrogenase family member, human short chain acyl-CoA dehydrogenase, was incubated with Dimethylglycine dehydrogenase and electron transferring flavoprotein, the microelectrospray ionization-mass spectrometry signal for the Dimethylglycine dehydrogenase·electron transferring flavoprotein complex decreased, indicating that the acyl-CoA dehydrogenases have the ability to compete with the Dimethylglycine dehydrogenase/sarcosine dehydrogenase family for access to electron transferring flavoprotein. Surface plasmon resonance solution competition experiments revealed affinity constants of 2.0 and 5.0 μm for the Dimethylglycine dehydrogenase-electron transferring flavoprotein and short chain acyl-CoA dehydrogenase-electron transferring flavoprotein interactions, respectively, suggesting the same or closely overlapping binding motif(s) on electron transferring flavoprotein for dehydrogenase interaction.
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cloning of Dimethylglycine dehydrogenase and a new human inborn error of metabolism Dimethylglycine dehydrogenase deficiency
American Journal of Human Genetics, 2001Co-Authors: Barbara A Binzak, Jerry Vockley, Ron A Wevers, Sytske H Moolenaar, Jo Poggibach, Udo F H Engelke, Heidi M HoardAbstract:Dimethylglycine dehydrogenase (DMGDH) (E.C. number 1.5.99.2) is a mitochondrial matrix enzyme involved in the metabolism of choline, converting Dimethylglycine to sarcosine. Sarcosine is then transformed to glycine by sarcosine dehydrogenase (E.C. number 1.5.99.1). Both enzymes use flavin adenine dinucleotide and folate in their reaction mechanisms. We have identified a 38-year-old man who has a lifelong condition of fishlike body odor and chronic muscle fatigue, accompanied by elevated levels of the muscle form of creatine kinase in serum. Biochemical analysis of the patient’s serum and urine, using 1H-nuclear magnetic resonance NMR spectroscopy, revealed that his levels of Dimethylglycine were much higher than control values. The cDNA and the genomic DNA for human DMGDH (hDMGDH) were then cloned, and a homozygous A→G substitution (326 A→G) was identified in both the cDNA and genomic DNA of the patient. This mutation changes a His to an Arg (H109R). Expression analysis of the mutant cDNA indicates that this mutation inactivates the enzyme. We therefore confirm that the patient described here represents the first reported case of a new inborn error of metabolism, DMGDH deficiency.
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structure and analysis of the human Dimethylglycine dehydrogenase gene
Molecular Genetics and Metabolism, 2000Co-Authors: Barbara A Binzak, Jerry Vockley, Jerry Vockley, Robert B JenkinsAbstract:Abstract Dimethylglycine dehydrogenase (DMGDH; E.C. 1.5.99.2) is an enzyme involved in the catabolism of choline, catalyzing the oxidative demethylation of Dimethylglycine (DMG) to form sarcosine. Subsequently, sarcosine dehydrogenase (SDH; E.C. 1.5.99.1) converts sarcosine to glycine via a similar reaction. Both enzymes are found as monomers in the mitochondrial matrix, and both contain 1 mol of covalently bound flavin adenine dinucleotide. DMGDH and SDH also utilize a noncovalently bound folate coenzyme that receives the “1-carbon” groups that are removed by DMGDH and SDH, forming “active formaldehyde.” We have recently described a new inborn error of metabolism of DMGDH characterized by an unusual fish-like body odor. To augment our study of this new disorder, we have isolated two human genomic clones that together contain 16 exons of coding sequence for the hDMGDH gene. Fluorescent in situ hybridization analysis of the hDMGDH gene indicates that it is found on chromosome 5q12.2–q12.3. In addition, several polymorphisms have been identified in the hDMGDH cDNA sequence. Population analysis of two Ser/Pro polymorphisms found 367 amino acids apart reveals a skew of alleles, with the haplotypes Ser/Pro or Pro/Ser (79%) overrepresented compared to the number of Ser/Ser or Pro/Pro alleles observed. Possible functional consequences of these findings are discussed. Characterization of the gene structure for hDMGDH will aid in the study of patients with inherited defects of this enzyme.
Sandy Slow - One of the best experts on this subject based on the ideXlab platform.
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the clinical significance of betaine an osmolyte with a key role in methyl group metabolism
Clinical Biochemistry, 2010Co-Authors: Michael Lever, Sandy SlowAbstract:Betaine is an essential osmolyte and source of methyl groups and comes from either the diet or by the oxidation of choline. Its metabolism methylates homocysteine to methionine, also producing N,N-Dimethylglycine. Betaine insufficiency is associated with the metabolic syndrome, lipid disorders and diabetes, and may have a role in vascular and other diseases. Betaine is important in development, from the pre-implantation embryo to infancy. Betaine supplementation improves animal and poultry health, but the effect of long-term supplementation on humans is not known, though reports that it improves athletic performance will stimulate further studies. Subsets of the population that may benefit from betaine supplementation could be identified by the laboratory, in particular those who excessively lose betaine through the urine. Plasma betaine is highly individual, in women typically 20–60 μmol/L and in men 25–75 μmol/L. Plasma Dimethylglycine is typically < 10 μmol/L. Urine betaine excretion is minimal, even following a large betaine dose. It is constant, highly individual and normally < 35 mmol/mole creatinine. The preferred method of betaine measurement is by LC-MS/MS, which is rapid and capable of automation. Slower HPLC methods give comparable results. Proton NMR spectrometry is another option but caution is needed to avoid confusion with trimethylamine-N-oxide.
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plasma and urine betaine and Dimethylglycine variation in healthy young male subjects
Clinical Biochemistry, 2009Co-Authors: Michael Lever, Wendy Atkinson, Sandy Slow, Stephen T Chambers, Peter M GeorgeAbstract:Objectives We aimed to compare the individuality (within subject consistency) of plasma and urine betaine and N,N-Dimethylglycine. Design and methods In two separate groups of 8 males (ages 19 to 40), plasma (10) and urine (6) samples were collected either over a single day or over an 8 week period. The individuality of the betaine and N,N-Dimethylglycine plasma concentrations and excretions were estimated by one-way repeated measures analysis of variance. The reliability coefficients and indices of individuality were calculated. The between-subject variation in the study population was compared with that in a normal population (n = 192 for plasma, 205 for urine). Results Plasma betaine concentrations were significantly different between subjects over 24 h and 8 weeks (p < 0.00001). Plasma Dimethylglycine concentrations were different over 24 h. Urine betaine and Dimethylglycine excretions were different in both (p < 0.0001). Betaine was more individual than Dimethylglycine in both plasma and urine. Compared with a normal healthy population, the between-subject variation in plasma betaine was less (p < 0.001) in the study group, but similar for Dimethylglycine and for urine betaine. Conclusions Plasma betaine and urinary betaine excretions are more individual than Dimethylglycine. Plasma and urine betaine are highly individual in the general population.
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Plasma and urine betaine and Dimethylglycine variation in healthy young male subjects.
Clinical Biochemistry, 2009Co-Authors: Michael Lever, Wendy Atkinson, Sandy Slow, Stephen T Chambers, Peter M GeorgeAbstract:Objectives We aimed to compare the individuality (within subject consistency) of plasma and urine betaine and N,N-Dimethylglycine. Design and methods In two separate groups of 8 males (ages 19 to 40), plasma (10) and urine (6) samples were collected either over a single day or over an 8 week period. The individuality of the betaine and N,N-Dimethylglycine plasma concentrations and excretions were estimated by one-way repeated measures analysis of variance. The reliability coefficients and indices of individuality were calculated. The between-subject variation in the study population was compared with that in a normal population (n = 192 for plasma, 205 for urine). Results Plasma betaine concentrations were significantly different between subjects over 24 h and 8 weeks (p
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Plasma and urine betaine and Dimethylglycine variation in healthy young male subjects.
Clinical biochemistry, 2009Co-Authors: Michael Lever, Wendy Atkinson, Sandy Slow, Stephen T Chambers, Peter M GeorgeAbstract:We aimed to compare the individuality (within subject consistency) of plasma and urine betaine and N,N-Dimethylglycine. In two separate groups of 8 males (ages 19 to 40), plasma (10) and urine (6) samples were collected either over a single day or over an 8 week period. The individuality of the betaine and N,N-Dimethylglycine plasma concentrations and excretions were estimated by one-way repeated measures analysis of variance. The reliability coefficients and indices of individuality were calculated. The between-subject variation in the study population was compared with that in a normal population (n=192 for plasma, 205 for urine). Plasma betaine concentrations were significantly different between subjects over 24 h and 8 weeks (p<0.00001). Plasma Dimethylglycine concentrations were different over 24 h. Urine betaine and Dimethylglycine excretions were different in both (p<0.0001). Betaine was more individual than Dimethylglycine in both plasma and urine. Compared with a normal healthy population, the between-subject variation in plasma betaine was less (p<0.001) in the study group, but similar for Dimethylglycine and for urine betaine. Plasma betaine and urinary betaine excretions are more individual than Dimethylglycine. Plasma and urine betaine are highly individual in the general population.
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Dimethylglycine supplementation does not affect plasma homocysteine concentrations in pre dialysis chronic renal failure patients
Clinical Biochemistry, 2004Co-Authors: Sandy Slow, Michael Lever, Stephen T Chambers, Peter M George, David O McgregorAbstract:Abstract Objective: To determine whether daily Dimethylglycine supplementation affects plasma homocysteine concentrations. Design and methods: A randomized, blinded, crossover design was used. Seven pre-dialysis chronic renal failure patients consumed 400 mg of Dimethylglycine or placebo daily for 28 days. Fasting blood samples and 12-h urine samples were collected at baseline and at the end of each treatment period for analysis. Results: No significant differences were observed in plasma homocysteine ( P = 0.624), glycine betaine ( P = 0.452) and methionine ( P = 0.457) concentrations between Dimethylglycine and placebo treatments. Conclusion: Daily supplementation with Dimethylglycine does not affect plasma homocysteine.