A colorimetric method for the determination of the principal metabolites of nicotinic acid in human urine

Holman, W. I. M.

doi:10.1042/bj0560513

Cited by 36 publications

(7 citation statements)

References 8 publications

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“…3-Hydroxykynurenine was determined fluorimetrically after reaction with ptoluene sulphonyl chloride in acetone (Watanabe er ut. 1970), N1-methyl nicotinamide by the small-scale modification of the alkali-ketone fluorimetric method of Carpenter & Kodicek (1950) that has been described previously (Bender,I980), and methyl-2-pyridone-4-carboxamide colorimetrically by hypobromite-catalysed rearrangement to the amine, diazotization and coupling to naphthyl ethylenediamine (Holman, 1954), after removal of potentially interfering substances with MB-5 1 13 mixed-bed ion-exchange resin (Bender, 1983 h).…”

Section: E T H O D Smentioning

confidence: 99%

Tryptophan metabolism in vitamin B₆-deficient mice

1990

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-_ _ -_~--_ _~_ _ _ _ _~~ Vitamin B, deficiency was induced in mice by maintenance for 4 weeks on a vitamin B,-free diet. Tryptophan metabolism was assessed by determining the urinary excretion of tryptophan metabolites, the metabolism of It4Cjtryptophan in vivo and the formation of tryptophan and niacin metabolites by isolated hepatocytes. The vitamin B,-deficient animals excreted more xanthurenic acid and 3-hydroxykynurenine, and less of the niacin metabolites N'-methyl nicotinamide and methyl-2-pyridone-4-carboxamide, than did control animals maintained on the same diet supplemented with 5 mg vitamin B,/kg. After intraperitoneal injection of ['4C]tryptophan, vitamin B,-deficient mice showed lower liberation of I4CO, from Imethylene-'4Cjtryptophan and IU-L4C)tryptophan than did controls, indicating impairment of kynureninase (EC 3 . 7 . 1 .3) activity. There was no difference between the two groups of animals in the metabolism of (ring-2-I4C]tryptophan. Hepatocytes isolated from the vitamin B,-deficient animals formed more 3-hydroxykynurenine and xanthurenic acid than did cells from control animals, but also formed more NADP and free niacin.

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Section: E T H O D Smentioning

confidence: 99%

Tryptophan metabolism in vitamin B₆-deficient mice

1990

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“…Measurement of NI--methyl nicotinamide W-Methyl nicotinamide in the incubation medium was determined by the small-scale modification of the alkali-ketone fluorimetric method of Carpenter & Kodicek (1 950) that has been described previously (Bender, 1980). Measurement of methyl pyridone carboxamide Methyl pyridone carboxamide in the incubation medium was determined colorimetrically after removal of interfering substances with MB-5 1 13 mixed-bed ion-exchange resin, hypobromite-catalysed rearrangement to the amine, diazotization, and coupling with napthylethylene diamine, as described previously by Bender (1983), a modification of the methods described by Holman (1954) and Joubert & de Lange (1962).…”

Section: Measurement Of Total Niacinmentioning

confidence: 99%

Utilization of tryptophan, nicotinamide and nicotinic acid as precursors for nicotinamide nucleotide synthesis in isolated rat liver cells

Bender

Olufunwa

1988

Br J Nutr

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1. Incubation of isolated rat hepatocytes with nicotinamide or nicotinic acid showed that while both vitamers were taken up from the incubation medium, neither was utilized to any significant extent as a precursor of the nicotinamide nucleotide coenzymes, NAD and NADP, and neither was capable of preventing the loss of nucleotides that occurs on incubating the cells.2. Incubation of hepatocytes with tryptophan showed that de novo synthesis from tryptophan permitted replacement of the nucleotides lost during incubation ; at high concentrations of tryptophan there was an increase above the initial intracellular concentration of NAD(P). Incubation of hepatocytes with tryptophan also resulted in the formation and release from the cells of a considerable amount of niacin, as well as the two principal metabolities of NAD(P), "-methyl nicotinamide and methyl pyridone carboxamide.3. It is suggested that, in the liver, preformed niacin is not utilized for nucleotide synthesis, and indeed the function of the liver appears to be synthesis of niacin from tryptophan, and its release for use by extrahepatic tissues that lack the pathway for de novo synthesis of nicotinamide nucleotides from tryptophan.Previous studies from this laboratory have suggested that the de novo synthesis of nicotinamide nucleotides (NAD and NADP) from tryptophan may be a more important source of these coenzymes than is the utilization of dietary nicotinamide or nicotinic acid. The enzyme kinetic variables are such that the three enzymes involved in the incorporation of preformed niacin into nucleotides, nicotinamide phosphoribosyltransferase (EC 2.4.2.12), arylformamidase (nicotinamide deamidase; EC 3.5.1 -19) and nicotinate phosphoribosyltransferase (EC 2.4.2.11) (see Fig. l), all act at or near their maximum rates at the normal intracellular concentrations of nicotinamide and nicotinic acid (Bender et al. 1982). This suggests that there would be little or no utilization of any additional niacin which might be available from the diet or arising from the catabolism of NAD(P).Feeding rats on diets providing high intakes of either nicotinic acid or nicotinamide leads to a relatively small increase in the concentration of NAD(P) in the liver. A tenfold increase in dietary niacin resulted in only a 50 % increase in liver NAD(P). By contrast, a threefold increase in dietary tryptophan resulted in a 2.6-fold increase in liver NAD(P), as well as a very considerable increase in the urinary excretion of "-methyl nicotinamide and methyl pyridone carboxyamide, the two principal metabolites of nicotinamide, resulting from hydrolysis of NAD(P) (McCreanor & Bender, 1986).The present study was undertaken in order to investigate further the relative importance of utilization of preformed niacin and de novo synthesis from tryptophan in the synthesis of nicotinamide nucleotide coenzymes in isolated rat hepatocytes. METHODS Cell preparation and incubationsMale Wistar rats, weighing 200 g, fed from weaning on animal house stock diet (Diet 86;

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“…Nicotinic acid and 3-pyridinecarboxamide (PA), which are also known as vitamin B 3 , are required for cell respiration, proper circulation, healthy skin, proper functioning of the nervous system, and normal secretion of bile and stomach fluids. [31] Several analytical methods have been developed and used for the determination of PA, including chromatographic, [31][32][33] spectrophotometric [34,35] and fluorometric methods. [36,37] Although all of these methods have shown sensitivity and specificity for the detection of PA, they are for the most part cumbersome, time-consuming, expensive, and require complicated clean-up procedures or sophisticated technical equipment.…”

Section: Introductionmentioning

confidence: 99%

Hydrogel Photonic Sensor for the Detection of 3‐Pyridinecarboxamide

Yuan

Liu

et al. 2011

Chemistry A European J

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Molecular imprinting is recognized as a powerful technique for preparing polymeric structures that contains tailor-made recognition sites for certain molecules. By combining a responsive hydrogel photonic crystal and molecular imprinting of 3-pyridinecarboxamide, polyacrylamide (PAM) imprinted photonic crystals (IPCs) with an inverse opal structure were prepared. They showed a rapid, recoverable, and selective response to 3-pyridinecarboxamide, which was detected by measuring the diffraction peak. The position of the diffraction peak could be tuned by copolymerizing acrylamide (AM) with acrylic acid (AA), by changing the ratio of AM to AA, by adding N,N'-methylene bisacrylamide to the monomers, or by imprinting molecules to monomers. More interestingly, the change in the Bragg diffraction of the IPCs can be directly converted into a readable optical signal that is visible to the naked eye without any labeling treatment.

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A colorimetric method for the determination of the principal metabolites of nicotinic acid in human urine

Cited by 36 publications

References 8 publications

Tryptophan metabolism in vitamin B₆-deficient mice

Tryptophan metabolism in vitamin B₆-deficient mice

Utilization of tryptophan, nicotinamide and nicotinic acid as precursors for nicotinamide nucleotide synthesis in isolated rat liver cells

Hydrogel Photonic Sensor for the Detection of 3‐Pyridinecarboxamide

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A colorimetric method for the determination of the principal metabolites of nicotinic acid in human urine

Cited by 36 publications

References 8 publications

Tryptophan metabolism in vitamin B6-deficient mice

Tryptophan metabolism in vitamin B6-deficient mice

Utilization of tryptophan, nicotinamide and nicotinic acid as precursors for nicotinamide nucleotide synthesis in isolated rat liver cells

Hydrogel Photonic Sensor for the Detection of 3‐Pyridinecarboxamide

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Tryptophan metabolism in vitamin B₆-deficient mice

Tryptophan metabolism in vitamin B₆-deficient mice