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Journal articles on the topic 'Urinary tryptophan'

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Published: 2 June 2025

Last updated: 31 July 2025

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1

Oshima, Shiiya, and Nakamura. "Combined Supplementation with Glycine and Tryptophan Reduces Purine-Induced Serum Uric Acid Elevation by Accelerating Urinary Uric Acid Excretion: A Randomized, Single-Blind, Placebo-Controlled, Crossover Study." Nutrients 11, no. 11 (2019): 2562. http://dx.doi.org/10.3390/nu11112562.

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The authors previously confirmed the serum uric acid-lowering effects of the combination of glycine and tryptophan in subjects with mild hyperuricemia. This study examined whether combined supplementation with glycine and tryptophan suppressed the elevation in serum uric acid levels caused by purine ingestion and accelerated urinary uric acid excretion in subjects with lower urate excretion using a randomized, single-blind, placebo-controlled, crossover clinical trial design. Healthy Japanese adult males with lower urate excretion ingested water containing purines in addition to dextrin (place

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2

Li Kam Wa, T. C., S. Freestone, R. R. Samson, N. R. Johnson, and M. R. Lee. "A Comparison of the Renal and Neuroendocrine Effects of Two 5-Hydroxytryptamine Renal Prodrugs in Normal Man." Clinical Science 85, no. 5 (1993): 607–14. http://dx.doi.org/10.1042/cs0850607.

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1. The effects of 1 h intravenous infusions of equimolar amounts (45 nmol min−1 kg−1) of two putative 5-hydroxytryptamine renal prodrugs, 5-hydroxy-L-tryptophan and γ-L-glutamyl-5-hydroxy-L-tryptophan, were investigated in a randomized, placebo-controlled, cross-over study in nine healthy male subjects. 2. Cumulative urinary 5-hydroxytryptamine excretion over the 3 h observation period rose by about 370-fold after 5-hydroxy-L-tryptophan and 390-fold after γ-L-glutamyl-5-hydroxy-L-tryptophan when compared with placebo infusion. Urinary 5-hydroxy-L-tryptophan excretion was three times higher aft

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3

Egashira, Yukari, Shin Nagaki, and Hiroo Sanada. "Tryptophan-Niacin Metabolism in Rat with Puromycin Aminonucleoside-Induced Nephrosis." International Journal for Vitamin and Nutrition Research 76, no. 1 (2006): 28–33. http://dx.doi.org/10.1024/0300-9831.76.1.28.

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We investigated the change of tryptophan-niacin metabolism in rats with puromycin aminonucleoside PAN-induced nephrosis, the mechanisms responsible for their change of urinary excretion of nicotinamide and its metabolites, and the role of the kidney in tryptophan-niacin conversion. PAN-treated rats were intraperitoneally injected once with a 1.0% (w/v) solution of PAN at a dose of 100 mg/kg body weight. The collection of 24-hour urine was conducted 8 days after PAN injection. Daily urinary excretion of nicotinamide and its metabolites, liver and blood NAD, and key enzyme activities of tryptoph

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Valko-Rokytovská, Marcela, Beáta Hubková, Anna Birková, et al. "Specific Urinary Metabolites in Malignant Melanoma." Medicina 55, no. 5 (2019): 145. http://dx.doi.org/10.3390/medicina55050145.

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Background and objectives: Melanin, which has a confirmed role in melanoma cell behaviour, is formed in the process of melanogenesis and is synthesized from tryptophan, L-tyrosine and their metabolites. All these metabolites are easily detectable by chromatography in urine. Materials and Methods: Urine samples of 133 individuals (82 malignant melanoma patients and 51 healthy controls) were analysed by reversed-phase high-performance liquid chromatography (RP-HPLC). The diagnosis of malignant melanoma was confirmed histologically. Results: Chromatograms of melanoma patients showed increased lev

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5

Wa, T. C. Li Kam, S. Freestone, R. R. Samson, N. R. Johnston, and M. R. Lee. "Renal Metabolism and Effects of the Glutamyl Derivatives of l-Dopa and 5-Hydroxytryptophan in Man." Clinical Science 91, no. 2 (1996): 177–85. http://dx.doi.org/10.1042/cs0910177.

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1. Equimolar amounts of y-l-glutamyl-l-3,4-dihydroxyphenylalanine (gludopa) and γ-l-glutamyl-5-hydroxy-l-tryptophan were infused separately and together in eight healthy, salt-replete male subjects in a placebo-controlled, cross-over study to investigate whether the administration of one amine precursor affects the renal metabolism of the other and to determine whether dopamine or 5-hydroxytryptamine would be generated preferentially. The overall effect on sodium excretion was also measured when both precursors were administered simultaneously. 2. Administration of gludopa was associated with

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6

Post, Adrian, Marleen Huberts, Enya Poppe, et al. "Tryptophan Intake and Tryptophan Losses in Hemodialysis Patients: A Balance Study." Nutrients 11, no. 12 (2019): 2851. http://dx.doi.org/10.3390/nu11122851.

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Tryptophan depletion is common in hemodialysis patients. The cause of this depletion remains largely unknown, but reduced nutritional tryptophan intake, losses during dialysis or an increased catabolism due to an inflammatory state are likely contributors. Currently, little is known about tryptophan homeostasis in hemodialysis patients. We assessed dietary tryptophan intake, measured plasma tryptophan during dialysis, and measured the combined urinary and dialysate excretion of tryptophan in 40 hemodialysis patients (66 ± 15 years and 68% male). Patients had low tryptophan concentrations (27 ±

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7

Williams, David J. "Tryptophan, urinary quinolines, and bladder cancer." Nutrition and Cancer 11, no. 2 (1988): 81–82. http://dx.doi.org/10.1080/01635588809513973.

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8

Fregly, Melvin J., Colin Sumners, and J. Robert Cade. "Effect of chronic dietary treatment with L-tryptophan on the maintenance of hypertension in spontaneously hypertensive rats." Canadian Journal of Physiology and Pharmacology 67, no. 6 (1989): 656–62. http://dx.doi.org/10.1139/y89-105.

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Chronic dietary administration of L-tryptophan at 2.5 and 5.0% by weight reduced the elevated systolic blood pressure of spontaneously hypertensive (SH) rats. Blood pressure was reduced significantly by 3 weeks after initiation of treatment and continued to fall during the course of the 15 weeks of treatment. Body weights of the treated rats were not affected significantly by treatment, nor were daily food and fluid intakes and urine outputs. SH rats, treated with the higher dose of tryptophan, also significantly reduced their urinary outputs of epinephrine and norepinephrine compared with SH

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9

Engin, Ayse Basak, Bensu Karahalil, Ali Esat Karakaya, and Atilla Engin. "Exposure to Helicobacter pylori and Serum Kynurenine to Tryptophan Ratio in Patients with Gastric Cancer." Pteridines 21, no. 1 (2010): 110–20. http://dx.doi.org/10.1515/pteridines.2010.21.1.110.

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Abstract In Helicobacter pylori seropositive individuals, the subsequent risk of non-cardia gastric cancer development is frequently attributed to the infection agent. Although the link between inflammation and gastric cancer is formally recognized, the molecular basis of evading mechanisms of Helicobacter pylori from host immune system remains unclear. The aim of this study was to determine the effect of systemic factors in gastric cancer patients such as serum kynurenine to tryptophan ratios, neopterin, nitric oxide and urinary biopterin levels which may sustain the persistence of Helicobact

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10

Fukuwatari and Shibata. "Effect of Nicotinamide Administration on the Tryptophan-Nicotinamide Pathway in Humans." International Journal for Vitamin and Nutrition Research 77, no. 4 (2007): 255–62. http://dx.doi.org/10.1024/0300-9831.77.4.255.

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The vitamin nicotinamide is synthesized in the liver from tryptophan, and distributed to non-hepatic tissues. Although it is generally accepted that 60 mg tryptophan is equivalent to 1 mg nicotinamide in humans, the conversion ratio of tryptophan to nicotinamide is changeable. To determine if de novo nicotinamide synthesis from tryptophan is influenced by nicotinamide intake itself, six young women consumed controlled diets containing 30.4 or 24.8 mg niacin-equivalent nicotinamide supplements with 0, 89, 310, or 562 μmol/day (0, 10.9, 37.8, or 68.6 mg/day, respectively), and urinary excretion

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Mede, Annmarie I., Ginger L. Milne, Dawei Wei, Derek K. Smith, and Loren E. Smith. "NAD+ Biosynthesis Impairment and Acute Kidney Injury after Major Vascular Surgery." Antioxidants 12, no. 4 (2023): 821. http://dx.doi.org/10.3390/antiox12040821.

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Acute kidney injury (AKI) is a serious complication after vascular surgery. Reduced synthesis of nicotinamide adenine dinucleotide (NAD+) from tryptophan is associated with an increased risk of AKI in critically ill patients, patients hospitalized with COVID-19, and cardiac surgery patients, and is marked by elevated urinary quinolinate and quinolinate to tryptophan ratios. We measured quinolinate concentrations in vascular surgery patients to determine if impaired NAD+ synthesis was associated with AKI in this patient population. Eight preoperative and eight postoperative vascular surgery pat

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12

Bender, David A., Eliud N. M. Njagi, and Paul S. Danielian. "Tryptophan metabolism in vitamin B6-deficient mice." British Journal of Nutrition 63, no. 1 (1990): 27–36. http://dx.doi.org/10.1079/bjn19900089.

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Vitamin B6 deficiency was induced in mice by maintenance for 4 weeks on a vitamin B6-free diet. Tryptophan metabolism was assessed by determining the urinary excretion of tryptophan metabolites, the metabolism of [14C]tryptophan in vivo and the formation of tryptophan and niacin metabolites by isolated hepatocytes. The vitamin B6-deficient animals excreted more xanthurenic acid and 3-hydroxykynurenine, and less of the niacin metabolites N1-methyl nicotinamide and methyl-2-pyridone-4-carboxamide, than did control animals maintained on the same diet supplemented with 5 mg vitamin B6/kg. After in

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13

Rueda, G. H., N. Causada-Calo, A. Nardelli, et al. "A248 THE ROLE OF DIETARY TRYPTOPHAN IN INDOLE AND KYNURENINE PRODUCTION AND IMMUNE MODULATION IN HEALTHY INDIVIDUALS." Journal of the Canadian Association of Gastroenterology 5, Supplement_1 (2022): 141–42. http://dx.doi.org/10.1093/jcag/gwab049.247.

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Abstract Background Natural supplements are widely consumed by the general public, with little evidence of mechanistic support. Tryptophan has gained central attention, being transformed by host and gut microbial enzymes into multiple bioactive metabolites that regulate immunity and mood. Indoles are activators of the aryl hydrocarbon receptor (AhR), crucial for the maintenance of intestinal homeostasis. Tryptophan has been advocated to prevent chronic inflammatory conditions, however the clinical data to support this are missing. Aims To investigate clinical, immune, and metabolic parameters

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14

Elkhafifi, Muftah H. "Purple Urine Bag Syndrome: Uncommon Clinical Entity Associated with Common Infection, Case Report." Al-Mukhtar Journal of Sciences 35, no. 3 (2020): 205–11. http://dx.doi.org/10.54172/mjsc.v35i3.250.

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Purple urine bag syndrome (PUBS) is a rare medical syndrome where purple discoloration of urine occurs predominantly in chronically constipated bedridden elderly women, chronically catheterized and associated with urinary tract infections (UTIs). The etiology is related to UTIs with specific bacteria that produce sulphatase and phosphatase enzymes which lead tryptophan metabolism to produce two pigments: Indigo (blue) and indirubin (red), mixtures of which become purple in color. Several risk factors are associated with PUBS; including female gender, increased dietary tryptophan, alkaline urin

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15

HIRATSUKA, Chiaki, Mitsue SANO, Tsutomu FUKUWATARI, and Katsumi SHIBATA. "Time-Dependent Effects of L-Tryptophan Administration on Urinary Excretion of L-Tryptophan Metabolites." Journal of Nutritional Science and Vitaminology 60, no. 4 (2014): 255–60. http://dx.doi.org/10.3177/jnsv.60.255.

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16

Bonner, Adrian B., Sarah Brien, and Victor R. Preedy. "The Urinary Excretion of Tryptophan and Tryptophan Metabolites in the Chronic Ethanol-fed Rat." Journal of Pharmacy and Pharmacology 45, no. 2 (1993): 81–85. http://dx.doi.org/10.1111/j.2042-7158.1993.tb03688.x.

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17

de Vries, Laura V., Isidor Minović, Casper F. M. Franssen, et al. "The tryptophan/kynurenine pathway, systemic inflammation, and long-term outcome after kidney transplantation." American Journal of Physiology-Renal Physiology 313, no. 2 (2017): F475—F486. http://dx.doi.org/10.1152/ajprenal.00690.2016.

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Tryptophan is metabolized along the kynurenine pathway, initially to kynurenine, and subsequently to cytotoxic 3-hydroxykynurenine. There is increasing interest in this pathway because of its proinflammatory nature, and drugs interfering in it have received increasing attention. We aimed to investigate whether serum and urinary parameters of the tryptophan/kynurenine pathway, and particularly cytotoxic 3-hydroxykynurenine, are associated with systemic inflammation and long-term outcome in renal transplant recipients (RTR). Data were collected in outpatient RTR with a functioning graft for >

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18

Hiratsuka, Chiaki, Tsutomu Fukuwatari, and Katsumi Shibata. "Fate of Dietary Tryptophan in Young Japanese Women." International Journal of Tryptophan Research 5 (January 2012): IJTR.S10497. http://dx.doi.org/10.4137/ijtr.s10497.

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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

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19

Kurum, H., and Ebru Yalcin. "Effects of multimodal environmental modification in crystal-related feline lower urinary tract diseases." Arquivo Brasileiro de Medicina Veterinária e Zootecnia 75, no. 4 (2023): 665–72. http://dx.doi.org/10.1590/1678-4162-12974.

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ABSTRACT This study aims to analyze the effects of multimodal environmental modification (MEMO) of cats with recurrence of lower urinary tract signs (LUTS). Treatment of FLUTD included pharmacological treatment, dietary management, and multimodal environmental modification approaches. Twenty client-owned indoor-housed cats with recurrence of lower urinary tract signs had been covered in this observation. Diagnosis of lower urinary tract was made primarily based on the cat's clinical signs, results of laboratory parameters, urinalysis and ultrasonographic examination. Cats were divided into two

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20

Hubková, Beáta, Marcela Valko-Rokytovská, Beáta Čižmárová, Marianna Zábavníková, Mária Mareková, and Anna Birková. "Tryptophan: Its Metabolism along the Kynurenine, Serotonin, and Indole Pathway in Malignant Melanoma." International Journal of Molecular Sciences 23, no. 16 (2022): 9160. http://dx.doi.org/10.3390/ijms23169160.

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(1) Background: Tryptophan metabolism is known to be one of the important mechanisms used by cancer to evade immune surveillance. Altered tryptophan metabolism was studied in patients with pigmented malignant melanoma confirmed histologically by the anatomic stage grouping for cutaneous melanoma using clinical staging on the basis of the Breslow thickness of the melanoma, the degree of spread to regional lymph nodes, and by the presence of distant metastasis. (2) Methods: Urinary tryptophan metabolites were detected by RP-HPLC method. (3) Results: In the present work, we provided evidence of a

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21

Noakes, Rowland R. "Effects of Tranilast on the Urinary Excretion of Kynurenic and Quinolinic Acid under Conditions of L Tryptophan Loading." International Journal of Tryptophan Research 6 (January 2013): IJTR.S12797. http://dx.doi.org/10.4137/ijtr.s12797.

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The pathogenesis of morphea and other cutaneous sclerosing disorders remain poorly understood. Although they are considered to be autoimmune disorders, abnormal tryptophan metabolism may be involved. Current therapy is directed to supressing the autoimmune response. Demonstration of a therapeutic response to manipulation of the kynurenine pathway would both support a role for abnormal tryptophan metabolism and offer additional targets for therapy. Tranilast is a 3-hydroxyanthranilic acid derivative known to target the kynurenine pathway. The aim of this study was to see if tranilast lowered th

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Rogerson, Ranae, Margie L. Gallagher, Eugenia M. Zallen, and Brian A. McMillen. "Urinary tryptophan metabolites in diabetic and non-diabetic juveniles." Nutrition Research 11, no. 11 (1991): 1251–56. http://dx.doi.org/10.1016/s0271-5317(05)80544-5.

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WILLIAMS, D. J. "Tryptophan metabolism and urinary quinoline bases in the greyhound." Research in Veterinary Science 41, no. 2 (1986): 273–74. http://dx.doi.org/10.1016/s0034-5288(18)30613-1.

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Ito, Yasuhiro, Hideomi Fukao, Akira Kaieda, et al. "Relationship between urinary tryptophan metabolites and longterm assisted circulation." Japanese Journal of Extra-Corporeal Technology 41, no. 1 (2014): 11–14. http://dx.doi.org/10.7130/jject.41.11.

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Gou, Xiao-jun, Shanshan Gao, Liang Chen, Qin Feng, and Yi-yang Hu. "A Metabolomic Study on the Intervention of Traditional Chinese Medicine Qushi Huayu Decoction on Rat Model of Fatty Liver Induced by High-Fat Diet." BioMed Research International 2019 (February 7, 2019): 1–14. http://dx.doi.org/10.1155/2019/5920485.

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Qushi Huayu Decoction (QHD), an important clinically proved herbal formula, has been reported to be effective in treating fatty liver induced by high-fat diet in rats. However, the mechanism of action has not been clarified at the metabolic level. In this study, a urinary metabolomic method based on gas chromatography-mass spectrometry (GC-MS) coupled with pattern recognition analysis was performed in three groups (control, model, and QHD group), to explore the effect of QHD on fatty liver and its mechanism of action. There was obvious separation between the model group and control group, and

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McCreanor, Gwyn M., and David A. Bender. "The metabolism of high intakes of tryptophan, nicotinamide and nicotinic acid in the rat." British Journal of Nutrition 56, no. 3 (1986): 577–86. http://dx.doi.org/10.1079/bjn19860138.

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1. The metabolic fate of high dietary intakes of nicotinamide, nicotinic acid and tryptophan, and of acute doses of nicotinamide and nicotinic acid, has been studied in the rat. A new high-pressure liquid chromatography method for measurement of the principal urinary metabolites of niacin is described.2. Administration to rats of a single oral dose of nicotinamide or nicotinic acid (up to 100 mg/kg body-weight), or maintenance for 3 weeks on diets providing 150 mg nicotinamide or nicotinic acid/kg diet, resulted in only a small increase in the liver content of nicotinamide nucleotide coenzymes

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Rajakumar, Rontgen, Nida Khan, and Abhishek Mahadik. "Purple urine bag syndrome: an unusual clinical presentation." International Journal of Research in Medical Sciences 8, no. 5 (2020): 1891. http://dx.doi.org/10.18203/2320-6012.ijrms20201944.

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Purple Urine Bag Syndrome (PUBS) is a rare presentation of urinary tract infection caused by certain bacteria that produce sulphatases and phosphatases that bring about metabolism of tryptophan, leading to production of pigments indigo and indirubin that together impart purple colour of urine. It is a benign condition, most often associated with long term urinary catheterization, renal diseases, chronic constipation and female gender. Commonly implicated organisms include Proteus mirabilis, Klebsiella pneumoniae, Providencia stuartii. Diagnosis is made on urinary culture. Treatment includes re

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Njagi, E. N. M., D. A. Bender, and G. B. A. Okelo. "Tryptophan metabolism and vitamin B6 nutritional status in patients with schistosomiasis mansoni and in infected mice." Parasitology 104, no. 3 (1992): 433–41. http://dx.doi.org/10.1017/s0031182000063691.

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Patients infected with Schistosoma mansoni showed an abnormal response to a test dose of tryptophan, with little increase in the urinary excretion of kynurenine, hydroxykynurenine, xanthurenic and kynurenic acids, N1-methyl nicotinamide, methyl pyridone carboxamide, 5-hydroxytryptamine or 5-hydroxyindoleacetic acid. In contrast to previous reports, this is different from the pattern of tryptophan metabolism seen in vitamin B6 deficiency. Furthermore, the patients' plasma concentrations of pyridoxal phosphate were within the reference range, and supplementation for 5 days with 20 mg vitamin B6/

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Blonska, Aleksandra, Marcin Chojnacki, Anna Macieja, et al. "Tryptophan Metabolism in Postmenopausal Women with Functional Constipation." International Journal of Molecular Sciences 25, no. 1 (2023): 273. http://dx.doi.org/10.3390/ijms25010273.

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Constipation belongs to conditions commonly reported by postmenopausal women, but the mechanism behind this association is not fully known. The aim of the present study was to determine the relationship between some metabolites of tryptophan (TRP) and the occurrence and severity of abdominal symptoms (Rome IV) in postmenopausal women with functional constipation (FC, n = 40) as compared with age-adjusted postmenopausal women without FC. All women controlled their TRP intake in their daily diet. Urinary levels of TRP and its metabolites, 5-hydroxyindoleacetic acid (5-HIAA), kynurenine (KYN), an

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Golovanov, S. A., V. N. Sinyukhin, V. A. Tashlitsky, et al. "Urinary excretion of tryptophan, lysine, trimethyllysine, sarcosine, choline and 4-pyridoxic acid in urolithiasis." Experimental and Сlinical Urology 15, no. 1 (2022): 68–75. http://dx.doi.org/10.29188/2222-8543-2022-15-1-68-75.

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Introduction. The role of the organic matrix in urinary stones genesis in urolithiasis patients is still unclear. The presence of a large amount of protein in the urinary stones matrix suggests the participation of the protein matrix in lithogenesis. Research of the amino acids spectrum in urine is of great interest so far as amino acids are the part of the matrix proteins of the urinary stone. Material and methods. We analyzed urinary excretion of the following amino acids and low molecular weight compounds: tryptophan, lysine, trimethyllysine, sarcosine, choline and 4-pyridoxine acid. We use

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Huber, Leonhard, Christiana Winkler, Katharina Schroecksnadel, Willi Geser, Christian Schubert, and Dietmar Fuchs. "Serial Analysis of Tryptophan Degradation and Neopterin Formation in an otherwise Healthy Individual before and during an Infectious Episode." Pteridines 17, no. 1 (2006): 25–30. http://dx.doi.org/10.1515/pteridines.2006.17.1.25.

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Abstract Thl-type cytokine interferon-y induces neopterin production in human monocyte-derived macrophages and it stimulates enzyme indoleamine (2,3)-dioxygenase (IDO) which converts tryptophan to kynurenine in various cells. In an integrative single-case study, a healthy, 27-year-old female had collected her entire urine in 12-hour (= I lag) intervals on 56 consecutive days. Neopterin, tryptophan, kynurenine and Creatinine concentrations were determined using HPLC. The kynurenine to tryptophan ratio (kyn/trp) was calcuiated as an index for IDO activity. Within the Observation period, the woma

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Nasimi, H., J. Skov Madsen, A. Hussein Zedan, et al. "Urinary tyrosine and tryptophan as potential biomarkers for prostate cancer." European Urology 81 (February 2022): S738—S739. http://dx.doi.org/10.1016/s0302-2838(22)00570-x.

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Oshima, Shunji, Sachie Shiiya, and Yasunori Nakamura. "Serum Uric Acid-Lowering Effects of Combined Glycine and Tryptophan Treatments in Subjects with Mild Hyperuricemia: A Randomized, Double-Blind, Placebo-Controlled, Crossover Study." Nutrients 11, no. 3 (2019): 564. http://dx.doi.org/10.3390/nu11030564.

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We determined the serum uric acid-lowering effects of combined daily supplementation of glycine and tryptophan in patients with mild hyperuricemia using a randomized, double-blind, placebo-controlled, crossover clinical trial design. Japanese healthy adult males and females with mild hyperuricemia (fasting serum uric acid of 6.6–7.9 mg/dL) ingested a powder mixture containing 3.0 g of glycine and 0.2 g of tryptophan or a placebo powder once daily at bedtime for 6 weeks. Combined supplementation with glycine and tryptophan significantly decreased serum uric acid levels (from 7.1 mg/dL to 6.7 mg

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Tomoda, Fumihiro, Masanobu Takata, Shinya Oh-Hashi, et al. "Altered renal response to enhanced endogenous 5-hydroxytryptamine after tryptophan administration in essential hypertension." Clinical Science 82, no. 5 (1992): 551–57. http://dx.doi.org/10.1042/cs0820551.

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1. To examine the pathophysiological significance of 5-hydroxytryptamine (serotonin) in essential hypertension, we compared the renal response to intrarenally formed 5-hydroxytryptamine by oral dosing with its precursor, L-tryptophan (2 g), in nine patients with essential hypertension and in six subjects with normotension. 2. Before tryptophan administration, urinary excretion of 5-hydroxytryptamine was significantly higher in the hypertensive group than in the normotensive group (66 ± 8 versus 36 ± 6 ng/min, P < 0.05), whereas renal plasma flow and glomerular filtration rate did not differ

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Alhaddad, Juliano, Fares Kosseifi, Nehme Raad, and Antoine Noujeim. "A Case Report: An Unusual Presentation of Purple Urinary Bag Syndrome." International Journal of Clinical Research 1, no. 1 (2020): 25–28. http://dx.doi.org/10.38179/ijcr.v1i1.15.

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Background: The Purple Urinary Bag Syndrome (PUBS) is an uncommon and under-reported syndrome. It results from the purple discoloration of urine by tryptophan-oxidizing bacteria in a favorable alkaline milieu and usually affects patients with indwelling catheters. Other risk factors include female gender, chronic constipation, tryptophan-rich diet, and cognitive impairment. Although asymptomatic in the majority of cases, PUBS may be the sole and earliest sign of an aggressive urinary tract infection, especially in elderly patients where the presentation may be atypical and associated with resi

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Amann, Anton, Bernhard Widner, Josef Rieder, et al. "Monitoring of immune activation using biochemical changes in a porcine model of cardiac arrest." Mediators of Inflammation 10, no. 6 (2001): 343–46. http://dx.doi.org/10.1080/09629350120102370.

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In animal models, immune activation is often difficult to assess because of the limited availability of specific assays to detect cytokine activities. In human monocytes/macrophages, interferon-γ induces increased production of neopterin and an enhanced activity of indoleamine 2,3-dioxygenase, which degrades tryptophan via the kynurenine pathway. Therefore, monitoring of neopterin concentrations and of tryptophan degradation can serve to detect the extent of T helper cell 1-type immune activation during cellular immune response in humans. In a porcine model of cardiac arrest, we examined the p

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Osredkar, Joško, Kristina Kumer, Uroš Godnov, et al. "Urinary Metabolomic Profile in Children with Autism Spectrum Disorder." International Journal of Molecular Sciences 26, no. 5 (2025): 2254. https://doi.org/10.3390/ijms26052254.

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Autism spectrum disorder (ASD) has been associated with disruptions in tryptophan (TRP) metabolism, affecting the production of key neuroactive metabolites. Investigating these metabolic pathways could yield valuable biomarkers for ASD severity and progression. We included 44 children with ASD and 44 healthy children, members of the same family. The average age in the ASD group was 10.7 years, while the average age in the control group was 9.4 years. Urinary tryptophan metabolites were quantified via liquid chromatography—mass spectrometry operating multiple reaction monitoring (MRM). Urinary

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Girgin, Gözde, Terken Baydar, Dietmar Fuchs, Gönül Sahin, Elif Özmert, and Kadriye Yurdakök. "Evaluation of Serum and Urinary Levels of some Pteridine Pathway Components in Healthy Turkish Children." Pteridines 23, no. 1 (2012): 90–95. http://dx.doi.org/10.1515/pteridines.2012.23.1.90.

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Abstract Neopterin, as a non-conjugated pteridine, is synthesized from guanosine triphosphate and its production is upregulated upon the activation of cellular immune response. Alterations of pteridines in body fluids are known to correlate well with existing diseases and stages, prognosis, clinical outcomes and survival data. It is of advantage to have a pteridine database of healthy volunteers to determine normal values. Thereby, especially in children there is no detailed study on pteridine levels. The aim of this study is to initiate the establishment of pteridine database of healthy child

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Timperio, Anna Maria, Federica Gevi, Francesca Cucinotta, et al. "Urinary Untargeted Metabolic Profile Differentiates Children with Autism from Their Unaffected Siblings." Metabolites 12, no. 9 (2022): 797. http://dx.doi.org/10.3390/metabo12090797.

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Autism Spectrum Disorder (ASD) encompasses a clinical spectrum of neurodevelopmental conditions that display significant heterogeneity in etiology, symptomatology, and severity. We previously compared 30 young children with idiopathic ASD and 30 unrelated typically-developing controls, detecting an imbalance in several compounds belonging mainly to the metabolism of purines, tryptophan and other amino acids, as well as compounds derived from the intestinal flora, and reduced levels of vitamins B6, B12 and folic acid. The present study describes significant urinary metabolomic differences withi

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Rueda, G. H., N. Causada-Calo, R. Borojevic, et al. "A8 DIETARY TRYPTOPHAN MODULATES KYNURENINE AND INDOLE PRODUCTION IN HEALTHY INDIVIDUALS." Journal of the Canadian Association of Gastroenterology 4, Supplement_1 (2021): 9–10. http://dx.doi.org/10.1093/jcag/gwab002.007.

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Abstract Background Tryptophan is an essential amino acid that is transformed by host and gut microbial enzymes into multiple bioactive metabolites that regulate immunity, mood and circadian rhythms. In particular, indoles, produced by gut bacterial metabolism of tryptophan, have recently gained central attention. Indoles are activators of the aryl hydrocarbon receptor (AhR), which is crucial for the maintenance of intestinal homeostasis and immunity. Tryptophan supplementation in fortified foods have been advocated to prevent chronic inflammatory conditions, from autism to chronic inflammatio

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Pavlova, Tereza, Veronika Vidova, Julie Bienertova-Vasku, et al. "Urinary intermediates of tryptophan as indicators of the gut microbial metabolism." Analytica Chimica Acta 987 (September 2017): 72–80. http://dx.doi.org/10.1016/j.aca.2017.08.022.

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Corcuff, Jean-Benoît, Laurence Chardon, Ines El Hajji Ridah, and Julie Brossaud. "Urinary sampling for 5HIAA and metanephrines determination: revisiting the recommendations." Endocrine Connections 6, no. 6 (2017): R87—R98. http://dx.doi.org/10.1530/ec-17-0071.

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Context Biogenic amines such as 5-hydroxy-indole acetic acid (5HIAA) the main metabolite of serotonin or metanephrines (catecholamines metabolites) are used as biomarkers of neuroendocrine tumours. Objective To re-evaluate the recommendations for urinary sampling (preservatives, diet, drugs, etc.) as many of the reported analytical interferences supporting these recommendations are related to obsolete assays. Methods Bibliographic analysis of old and modern assays concerning preservation, extraction, assay and interferences. Results 5HIAA may degrade as soon as urine is excreted. Thus, acids a

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Matsumoto-Miyai, Kazumasa, Erika Yamada, Eriko Shinzawa, et al. "Serotonergic regulation of distention-induced ATP release from the urothelium." American Journal of Physiology-Renal Physiology 310, no. 7 (2016): F646—F655. http://dx.doi.org/10.1152/ajprenal.00024.2015.

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Serotonin [5-hydroxytryptamine (5-HT)] is involved in both motor and sensory functions in hollow organs, especially in the gastrointestinal tract. However, the involvement of 5-HT in visceral sensation of the urinary bladder remains unknown. Because distention-induced ATP release from the urothelium plays an essential role in visceral sensation of the urinary bladder, we investigated the regulation of urothelial ATP release by the 5-HT signaling system. RT-PCR and immunohistochemical analyses of the urothelium revealed specific expression of 5-HT1D and 5-HT4 receptors. The addition of 5-HT did

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Brunetto, Marcio Antonio, Doris Pereira Halfen, Larissa Wunsche Risolia, et al. "Evaluation of Serum and Urine Amino Acids in Dogs with Chronic Kidney Disease and Healthy Dogs Fed a Renal Diet." Metabolites 11, no. 12 (2021): 844. http://dx.doi.org/10.3390/metabo11120844.

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This observational study aimed to evaluate serum and urinary amino acid (AA) concentrations in healthy dogs and dogs with chronic kidney disease (CKD) fed a commercial therapeutic renal diet with reduced protein and phosphorus levels. Ten dogs with CKD stages 3 or 4 composed the study group and received the renal diet for 180 days (RG T180). A control group (CG T30) composed of seven healthy dogs was fed a renal diet for 30 days. When comparing serum AA between RG T180 and CG T30, histidine, isoleucine, leucine, lysine, phenylalanine, tryptophan, cysteine, citrulline, ornithine, taurine, branc

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Deen, Carolien P. J., Anna van der Veen, Martijn van Faassen, et al. "Urinary Excretion of N1-Methylnicotinamide, as a Biomarker of Niacin Status, and Mortality in Renal Transplant Recipients." Journal of Clinical Medicine 8, no. 11 (2019): 1948. http://dx.doi.org/10.3390/jcm8111948.

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Renal transplant recipients (RTR) commonly suffer from vitamin B6 deficiency and its functional consequences add to an association with poor long-term outcome. It is unknown whether niacin status is affected in RTR and, if so, whether this affects clinical outcomes, as vitamin B6 is a cofactor in nicotinamide biosynthesis. We compared 24-h urinary excretion of N1-methylnicotinamide (N1-MN) as a biomarker of niacin status in RTR with that in healthy controls, in relation to dietary intake of tryptophan and niacin as well as vitamin B6 status, and investigated whether niacin status is associated

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Chojnacki, Cezary, Marta Medrek-Socha, Aleksandra Blonska, Radoslaw Zajdel, Jan Chojnacki, and Tomasz Poplawski. "A Reduced Tryptophan Diet in Patients with Diarrhoea-Predominant Irritable Bowel Syndrome Improves Their Abdominal Symptoms and Their Quality of Life through Reduction of Serotonin Levels and Its Urinary Metabolites." International Journal of Molecular Sciences 23, no. 23 (2022): 15314. http://dx.doi.org/10.3390/ijms232315314.

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(1). An essential component of any treatment for patients with irritable bowel syndrome (IBS) is an adequate diet. Currently, a low FODMAP diet is recommended as a first-line therapy, but it does not relieve abdominal discomfort in all patients, and alternative nutritional treatment is required. The purpose of this study was to evaluate the effect of a tryptophan-lowering diet (TRP) on abdominal and mental symptoms in patients with irritable bowel syndrome with predominant diarrhea (IBS-D). (2). The study included 40 patients with IBS-D, and 40 healthy subjects served as a baseline for IBS-D p

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Fregly, Melvin J., Ora E. Lockley, Judith van der Voort, Colin Sumners, and William N. Henley. "Chronic dietary administration of tryptophan prevents the development of deoxycorticosterone acetate salt induced hypertension in rats." Canadian Journal of Physiology and Pharmacology 65, no. 5 (1987): 753–64. http://dx.doi.org/10.1139/y87-122.

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Hypertension developed within 3 to 5 weeks in uninephrectomized rats administered deoxycorticosterone acetate (DOCA) at a dose of 850 μg∙kg−1∙day−1 via Silastic tubes and given isotonic saline to drink. Chronic dietary administration of tryptophan (25 and 50 g/kg of food) to DOCA-treated rats reduced their exaggerated intake of NaCl solution and attenuated the elevation of blood pressure induced by treatment with DOCA alone. Treatment with tryptophan also protected against the reduction in urinary concentrating ability during a 24-h dehydration that is characteristic of DOCA-treated rats. Othe

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Chojnacki, Cezary, Tomasz Popławski, Jan Chojnacki, Michał Fila, Paulina Konrad, and Janusz Blasiak. "Tryptophan Intake and Metabolism in Older Adults with Mood Disorders." Nutrients 12, no. 10 (2020): 3183. http://dx.doi.org/10.3390/nu12103183.

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The role of serotonin in the pathogenesis of depression is well-documented, while the involvement of other tryptophan (TRP) metabolites generated in the kynurenine pathway is less known. The aim of this study was to assess the intake and metabolism of TRP in elderly patients with mood disorders. Ninety subjects in three groups, 30 subjects each, were enrolled in this study: controls (healthy young adults, group I) and elderly individuals without (group II) or with (group III) symptoms of mild and moderate depression, as assessed by the Hamilton Depression Rating Scale (HAM-D) and further refer

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Yarbrough, Melanie L., Kelleigh E. Briden, John V. Mitsios, et al. "Mass spectrometric measurement of urinary kynurenine-to-tryptophan ratio in children with and without urinary tract infection." Clinical Biochemistry 56 (June 2018): 83–88. http://dx.doi.org/10.1016/j.clinbiochem.2018.04.014.

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Sobotka, Wiesław, and Aleksandra Drażbo. "The Effect of Dietary Protein Restriction in Phase Feeding Systems on Nitrogen Metabolism and Excretion in Pig Production." Animals 15, no. 11 (2025): 1521. https://doi.org/10.3390/ani15111521.

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In recent years, much attention has been paid to environmental protection, not only by reducing emissions of harmful gases from industry, but also by reducing the excretion of biogenic compounds or ammonia emissions from agriculture, including animal production. The aim of this study was to determine the effects of complete diets with reduced inclusion levels of crude protein and limiting essential amino acids, fed to pigs in two- and three-phase feeding systems, and the feeding system on crude protein digestibility, nitrogen retention and utilization, fecal and urinary pH, fecal and urinary n

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