Analysis of tryptophan catabolism in HBV patients by HPLC with programmed wavelength ultraviolet detection

Ma, Li; Xu, Bo; Wang, Wenjuan; Deng, Wenli; Ding, Min

doi:10.1016/j.cca.2009.04.009

Cited by 19 publications

(15 citation statements)

References 18 publications

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“…In particular, the data about the fate of Trp at the basal level (ie, the fate of Trp without Trp loading) are considered unreliable. Recently, modern chromatographic separation of Trp and its metabolites has been reported 47–49. Shibata and co-workers25–34 developed HPLC measurements of Trp and its metabolites in urine samples, gradually modified these methods, and recently developed the HPLC measurement of 2-OAA, which is an intermediate of the Trp-glutarate pathway.…”

Section: Discussionmentioning

confidence: 99%

Fate of Dietary Tryptophan in Young Japanese Women

Hiratsuka

Fukuwatari

Shibata

2012

Int J�Tryptophan�Res

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The purpose of this study was to determine, using the high-performance liquid chromatographic methods recently modified by us, the fate of dietary tryptophan in 17 healthy female Japanese adults who ate self-selected food. The experimental period was 22 days. The habitual intake of tryptophan was 3328.4 μmol/day. 24-hour urine samples were collected at the beginning of the experiment and then once per week. Blood was collected at the beginning and end of the experiment. Levels of tryptophan and its metabolites were measured in blood and urine. Tryptophan, nicotinamide and 2-oxoadipic acid were the major compounds of the blood. The urinary excretion amounts of tryptophan, 5-hydroxyindole-3-acetic acid, kynurenine, anthranilic acid, kynurenic acid, 3-hydroxykynurenine, xanthurenic acid, 3-hydroxyanthranilic acid and quinolinic acid were about 40, 20, 4, 1, 10, 4, 3, 5 and 20 μmol/day, respectively.

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Section: Discussionmentioning

confidence: 99%

Fate of Dietary Tryptophan in Young Japanese Women

Hiratsuka

Fukuwatari

Shibata

2012

Int J�Tryptophan�Res

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“…Proteins in plasma are frequently removed through a pretreatment of sample with acids and by SPE. Deproteinization with perchloric acid (PCA) and trichloroacetic acid (TCA) might be used for this purpose. The sample mixed with acid is shaken and centrifuged to separate precipitated proteins from Trp and kynurenines present in supernatant.…”

Section: Sample Preparation For Chromatographic Analysis Of Kynureninesmentioning

confidence: 99%

Chromatographic analysis of tryptophan metabolites

Sadok

Gamian

Staniszewska

2017

J of Separation Science

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The kynurenine pathway generates multiple tryptophan metabolites called collectively kynurenines and leads to formation of the enzyme cofactor nicotinamide adenine dinucleotide. The first step in this pathway is tryptophan degradation, initiated by the rate‐limiting enzymes indoleamine 2,3‐dioxygenase, or tryptophan 2,3‐dioxygenase, depending on the tissue. The balanced kynurenine metabolism, which has been a subject of multiple studies in last decades, plays an important role in several physiological and pathological conditions such as infections, autoimmunity, neurological disorders, cancer, cataracts, as well as pregnancy. Understanding the regulation of tryptophan depletion provide novel diagnostic and treatment opportunities, however it requires reliable methods for quantification of kynurenines in biological samples with complex composition (body fluids, tissues, or cells). Trace concentrations, interference of sample components, and instability of some tryptophan metabolites need to be addressed using analytical methods. The novel separation approaches and optimized extraction protocols help to overcome difficulties in analyzing kynurenines within the complex tissue material. Recent developments in chromatography coupled with mass spectrometry provide new opportunity for quantification of tryptophan and its degradation products in various biological samples. In this review, we present current accomplishments in the chromatographic methodologies proposed for detection of tryptophan metabolites and provide a guide for choosing the optimal approach.

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“…lTryptophan is an essential amino acid that is required for the biosynthesis of proteins and is the precursor for several important biological compounds [1,2]. l-Tryptophan is also an important amino acid in terms of its applications in the pharmaceutical, food, and cosmetics industries [3,4].…”

Section: Introductionmentioning

confidence: 99%