crotonic-acid-betaine and gamma-butyrobetaine

Animal studies suggest that gut microbiome metabolites such as trimethylamine N-oxide (TMAO) may influence cognitive function and dementia risk. However potential health effects of TMAO and related metabolites remain unclear.. We examined prospective associations of TMAO, γ-butyrobetaine, crotonobetaine, carnitine, choline, and betaine with risk of cognitive impairment and dementia among older adults aged 65 years and older in the Cardiovascular Health Study (CHS).. TMAO and metabolites were measured in stored plasma specimens collected at baseline. Incident cognitive impairment was assessed using the 100-point Modified Mini-Mental State Examination administered serially up to 7 times. Clinical dementia was identified using neuropsychological tests adjudicated by CHS Cognition Study investigators, and by ICD-9 codes from linked Medicare data. Associations of each metabolite with cognitive outcomes were assessed using Cox proportional hazards models.. Over a median of 13 years of follow-up, 529 cases of cognitive impairment, and 522 of dementia were identified. After multivariable adjustment for relevant risk factors, no associations were seen with TMAO, carnitine, choline, or betaine. In contrast, higher crotonobetaine was associated with 20-32% higher risk of cognitive impairment and dementia per interquintile range (IQR), while γ-butyrobetaine was associated with ∼25% lower risk of the same cognitive outcomes per IQR.∥Conclusion:These findings suggest that γ-butyrobetaine, crotonobetaine, two gut microbe and host metabolites, are associated with risk of cognitive impairment and dementia. Our results indicate a need for mechanistic studies evaluating potential effects of these metabolites, and their interconversion on brain health, especially later in life.

Topics: Animals; Betaine; Carnitine; Choline; Cognitive Dysfunction; Dementia; Medicare; Methylamines; United States

Trimethylamine N-oxide (TMAO), a gut-related metabolite, is associated with heart failure (HF) outcomes. However, TMAO is the final product of a complex metabolic pathway (ie, choline/carnitine) that has never been entirely investigated in HF. The present study investigates a panel of metabolites involved in the TMAO-choline/carnitine metabolic pathway for their associations with outcome in acute HF patients.. In total, 806 plasma samples from acute HF patients were analyzed for TMAO, trimethyllysine, L-carnitine, acetyl-L-carnitine, γ-butyrobetaine, crotonobetaine, trimethylamine, betaine aldehyde, choline, and betaine using a developed liquid chromatography-tandem mass spectrometry method. Associations with outcome of all-cause mortality (death) and a composite of all-cause mortality and/or rehospitalization caused by HF (death/HF) at 30 days and 1 year were investigated.. TMAO, trimethyllysine, L-carnitine, acetyl-L-carnitine, and γ-butyrobetaine were associated with death and death/HF at 30 days (short term; hazard ratio 1.30-1.49, P≤ .021) and at 1 year (long term; hazard ratio 1.15-1.25, P≤ .026) when adjusted for cardiac risk factors. L-carnitine and acetyl-L-carnitine were superior for short-term outcomes whereas TMAO was the superior metabolite for association with long-term outcomes. Furthermore, acetyl-L-carnitine and L-carnitine were superior for in-hospital mortality and improved risk stratification when combined with current clinical risk scores (ie, Acute Decompensated HEart Failure National REgistry, Organized Program To Initiate Lifesaving Treatment In Hospitalized Patients With Heart Failure, and Get With The Guidelines-Heart Failure; odds ratio (OR) ≥ 1.52, P≤ .020).. Carnitine-related metabolites show associations with adverse outcomes in acute HF, in particular L-carnitine and acetyl-L-carnitine for short-term outcomes, and TMAO for long-term outcomes. Further studies are warranted to investigate the role and implications of carnitine metabolites including intervention in the pathogenesis of HF.

Topics: Acetylcarnitine; Acute Disease; Aged; Aged, 80 and over; Betaine; Carnitine; Choline; Female; Gastrointestinal Microbiome; Heart Failure; Hospital Mortality; Humans; Male; Methylamines; Natriuretic Peptide, Brain; Risk Factors; Statistics, Nonparametric

Proteus sp. is able to catalyse the reversible transformation of crotonobetaine into L(-)-carnitine during aerobic growth. Contrary to other Enterobacteriaceae no reduction of crotonobetaine into gamma-butyrobetaine could be detected in the culture supernatants. Activities of L(-)-carnitine dehydratase, carnitine racemasing system and crotonobetaine reductase could be determined enzymatically in cell-free extracts of Proteus sp. Small amounts of gamma-butyrobetaine were found in cell-free extracts, indicating that it accumulates in the cell and inhibits the crotonobetaine reductase. Crotonobetaine and L(-)-carnitine were able to induce enzymes of carnitine metabolism. gamma-Butyrobetaine and glucose repress carnitine metabolism in Proteus sp. Other betaines are neither inducers nor repressors. Monoclonal antibodies against purified CaiA from Escherichia coli O44K74 recognise an analogous protein in cell-free extract of Proteus sp. No cross-reactivity could be detected with monoclonal antibodies against purified CaiB and CaiD from E. coli O44K74.

Topics: Acyltransferases; Aerobiosis; Betaine; Carnitine; Enzyme Induction; Enzyme Repression; Escherichia coli Proteins; Hydro-Lyases; Multienzyme Complexes; Oxidoreductases; Proteus; Racemases and Epimerases

Two proteins (CaiB and CaiD) were found to catalyze the reversible biotransformation of crotonobetaine to L-carnitine in Escherichia coli in the presence of a cosubstrate (e.g., gamma-butyrobetainyl-CoA or crotonobetainyl-CoA). CaiB (45 kDa) and CaiD (27 kDa) were purified in two steps to electrophoretic homogeneity from overexpression strains. CaiB was identified as crotonobetainyl-CoA:carnitine CoA-transferase by MALDI-TOF mass spectrometry and enzymatic assays. The enzyme exhibits high cosubstrate specificity to CoA derivatives of trimethylammonium compounds. In particular, the N-terminus of CaiB shows significant identity with other CoA-transferases (e.g., FldA from Clostridium sporogenes, Frc from Oxalobacter formigenes, and BbsE from Thauera aromatica) and CoA-hydrolases (e.g., BaiF from Eubacterium sp.). CaiD was shown to be a crotonobetainyl-CoA hydratase using MALDI-TOF mass spectrometry and enzymatic assays. Besides crotonobetainyl-CoA CaiD is also able to hydrate crotonyl-CoA with a significantly lower Vmax (factor of 10(3)) but not crotonobetaine. The substrate specificity of CaiD and its homology to the crotonase confirm this enzyme as a new member of the crotonase superfamily. Concluding these results, it was verified that hydration of crotonobetaine to L-carnitine proceeds at the CoA level in two steps: the CaiD catalyzed hydration of crotonobetainyl-CoA to L-carnitinyl-CoA, followed by a CoA transfer from L-carnitinyl-CoA to crotonobetaine, catalyzed by CaiB. When gamma-butyrobetainyl-CoA was used as a cosubstrate (CoA donor), the first reaction is the CoA transfer. The optimal ratios of CaiB and CaiD during this hydration reaction, determined to be 4:1 when crotonobetainyl-CoA was used as cosubstrate and 5:1 when gamma-butyrobetainyl-CoA was used as cosubstrate, are different from that found for in vivo conditions (1:3).

Topics: Acyl Coenzyme A; Acyltransferases; Amino Acid Sequence; Antibodies, Monoclonal; Betaine; Carnitine; Enoyl-CoA Hydratase; Escherichia coli; Escherichia coli Proteins; Models, Chemical; Molecular Sequence Data; Proteus; Racemases and Epimerases; Sequence Homology, Amino Acid

A still unknown low-molecular-mass cofactor essential for the activity of carnitine-metabolizing enzymes (e.g., L-carnitine dehydratase, crotonobetaine reductase) from E. coli has been purified to homogeneity from a cell-free extract of E. coli O44K74. The purity of the cofactor was confirmed by HPLC analysis. Biosynthesis of the unknown compound was only observed when bacteria were cultivated anaerobically in the presence of L-carnitine or crotonobetaine. The determined properties, together with results obtained from UV-visible, (1)H NMR, and mass spectrometry, indicate that the compound in question is a new CoA derivative. The esterified compound was suggested to be gamma-butyrobetaine-a metabolite of carnitine metabolism of E. coli. Proof of structure was performed by chemical synthesis. Besides gamma-butyrobetainyl-CoA, a second new CoA derivative, crotonobetainyl-CoA, was also chemically synthesized. Both CoA derivatives were purified and their structures confirmed using NMR and mass spectrometry. Comparisons of structural data and of the chemical properties of gamma-butyrobetainyl-CoA, crotonobetainyl-CoA, and the isolated cofactor verified that the unknown compound is gamma-butyrobetainyl-CoA. The physical and chemical properties of gamma-butyrobetainyl-CoA and crotonobetainyl-CoA are similar to known CoA derivatives.

Topics: Acyl Coenzyme A; Acyltransferases; Betaine; Carnitine; Chemical Phenomena; Chemistry, Physical; Chromatography, High Pressure Liquid; Escherichia coli; Hydro-Lyases; Mass Spectrometry; Molecular Weight; Nuclear Magnetic Resonance, Biomolecular; Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; Spectrophotometry, Ultraviolet

The uptake of L-carnitine by Escherichia coli 044 K74 which is able to metabolize L-carnitine to gamma-butyrobetaine under anaerobic conditions was studied. The uptake system of E. coli was induced in the presence of L-carnitine or crotonobetaine. The optimum influx of L-carnitine was found to take place at 37 degrees C in phosphate buffer, pH 7.5. On the basis of the temperature dependence of the uptake rate an activation energy of 53.5 kJ/mol was estimated. The transport of L-carnitine was energy dependent. The kinetics of L-carnitine entry followed the Michaelis-Menten relationship yielding a Km value of 5.3 x 10(-4) M and a Vmax of 154 nmol/min.mg protein. The transport system showed considerable structural specificity for trimethylamine carboxylic molecules. The results suggest that E. coli possesses an inducible, active and carrier-mediated uptake system for L-carnitine.

Topics: 2,4-Dinitrophenol; Anaerobiosis; Betaine; Binding, Competitive; Biological Transport, Active; Carbonyl Cyanide m-Chlorophenyl Hydrazone; Carnitine; Dinitrophenols; Escherichia coli; Hydrogen-Ion Concentration; Oxidation-Reduction; Temperature; Uncoupling Agents

Topics: Betaine; Carnitine; Crotonates; Enterobacteriaceae

Topics: Administration, Oral; Animals; Betaine; Butyrates; Carnitine; Crotonates; Kinetics; Mice; Oxidation-Reduction; Rats; Species Specificity

Topics: Aerobiosis; Anaerobiosis; Animals; Betaine; Carnitine; Crotonates; Culture Media; Escherichia coli; Intestines; Oxidation-Reduction; Rats; Stereoisomerism

Topics: Animals; Betaine; Carnitine; Choline; Folic Acid; Sarcoma, Experimental; Vitamin B Complex