scholarly journals Stochastic Resonance Activity Influences Serum Tryptophan Metabolism in Healthy Human Subjects

2011 ◽  
Vol 4 ◽  
pp. IJTR.S7986 ◽  
Author(s):  
Berthold Kepplinger ◽  
Halina Baran ◽  
Brenda Sedlnitzky-Semler ◽  
Nagy-Roland Badawi ◽  
Helene Erhart

Background Stochastic resonance therapy (SRT) is used for rehabilitation of patients with various neuropsychiatric diseases. An alteration in tryptophan metabolism along the kynurenine pathway has been identified in the central and peripheral nervous systems in patients with neuroinflammatory and neurodegenerative diseases and during the aging process. This study investigated the effect of SRT as an exercise activity on serum tryptophan metabolites in healthy subjects. Methods Serum L-tryptophan, L-kynurenine, kynurenic acid, and anthranilic acid levels were measured one minute before SRT and at one, 5, 15, 30, and 60 minutes after SRT. We found that SRT affected tryptophan metabolism. Serum levels of L-tryptophan, L-kynurenine, and kynurenic acid were significantly reduced for up to 60 minutes after SRT. Anthranilic acid levels were characterized by a moderate, non significant transient decrease for up to 15 minutes, followed by normalization at 60 minutes. Tryptophan metabolite ratios were moderately altered, suggesting activation of metabolism after SRT. Lowering of tryptophan would generally involve activation of tryptophan catabolism and neurotransmitter, protein, and bone biosynthesis. Lowering of kynurenic acid by SRT might be relevant for improving symptoms in patients with neuropsychiatric disorders, such as Parkinson's disease, Alzheimer's disease, schizophrenia, and depression, as well as certain pain conditions.

2021 ◽  
Vol 22 (1) ◽  
Author(s):  
Bernadett Tuka ◽  
Aliz Nyári ◽  
Edina Katalin Cseh ◽  
Tamás Körtési ◽  
Dániel Veréb ◽  
...  

Abstract Background Altered glutamatergic neurotransmission and neuropeptide levels play a central role in migraine pathomechanism. Previously, we confirmed that kynurenic acid, an endogenous glutamatergic antagonist, was able to decrease the expression of pituitary adenylate cyclase-activating polypeptide 1–38, a neuropeptide with known migraine-inducing properties. Hence, our aim was to reveal the role of the peripheral kynurenine pathway (KP) in episodic migraineurs. We focused on the complete tryptophan (Trp) catabolism, which comprises the serotonin and melatonin routes in addition to kynurenine metabolites. We investigated the relationship between metabolic alterations and clinical characteristics of migraine patients. Methods Female migraine patients aged between 25 and 50 years (n = 50) and healthy control subjects (n = 34) participated in this study. Blood samples were collected from the cubital veins of subjects (during both the interictal/ictal periods in migraineurs, n = 47/12, respectively). 12 metabolites of Trp pathway were determined by neurochemical measurements (UHPLC-MS/MS). Results Plasma concentrations of the most Trp metabolites were remarkably decreased in the interictal period of migraineurs compared to healthy control subjects, especially in the migraine without aura (MWoA) subgroup: Trp (p < 0.025), L-kynurenine (p < 0.001), kynurenic acid (p < 0.016), anthranilic acid (p < 0.007), picolinic acid (p < 0.03), 5-hydroxy-indoleaceticacid (p < 0.025) and melatonin (p < 0.023). Several metabolites showed a tendency to elevate during the ictal phase, but this was significant only in the cases of anthranilic acid, 5-hydroxy-indoleaceticacid and melatonin in MWoA patients. In the same subgroup, higher interictal kynurenic acid levels were identified in patients whose headache was severe and not related to their menstruation cycle. Negative linear correlation was detected between the interictal levels of xanthurenic acid/melatonin and attack frequency. Positive associations were found between the ictal 3-hydroxykynurenine levels and the beginning of attacks, just as between ictal picolinic acid levels and last attack before ictal sampling. Conclusions Our results suggest that there is a widespread metabolic imbalance in migraineurs, which manifests in a completely depressed peripheral Trp catabolism during the interictal period. It might act as trigger for the migraine attack, contributing to glutamate excess induced neurotoxicity and generalised hyperexcitability. This data can draw attention to the clinical relevance of KP in migraine.


1995 ◽  
Vol 89 (6) ◽  
pp. 591-599 ◽  
Author(s):  
Roger J. W. Truscott ◽  
Anthony J. Elderfield

1. Cataract is the single major cause of blindness worldwide; however, the reasons for the development of this condition remain unknown. It has been suggested that the essential amino acid tryptophan may be implicated in the aetiology but definitive evidence has been lacking. 2. The serum levels of tryptophan and seven of its metabolites have been measured in both cataract patients and control subjects, after administration of tryptophan, in order to determine the typical response profile and to discover whether differences could be found in tryptophan metabolism in the two groups. 3. Tryptophan, kynurenine, kynurenic acid, xanthurenic acid, 3-hydroxyanthranilic acid, 5-hydroxyanthranilic acid, 5-hydroxytryptophan and anthranilic acid were measured by HPLC with dual electrochemical and programmable wavelength fluorescence detection. Fasting cataract patients (n = 42) and control subjects (n = 37) were given an oral dose of l-tryptophan and sera were sampled at 0, 1, 2, 4 and 6 h. 4. Statistically significant differences in the distribution of data between the two groups were observed. The responses of kynurenine and 5-hydroxyanthranilic acid were higher in cataract patients, but those of kynurenic acid and total tryptophan were lower than in control subjects. No statistically significant differences in free tryptophan, anthranilic acid, 3-hydroxyanthranilic acid, xanthurenic acid or 5-hydroxytryptophan levels were noted. 5. We conclude that there is a major subgroup of age-related cataract patients with a dysfunction in the metabolism of tryptophan. This may be related to the onset of cataract. The mechanism remains to be established but may operate via the action of tryptophan metabolites, such as 5-hydroxyanthranilic acid, which become reactive towards protein upon oxidation.


2020 ◽  
Vol 13 ◽  
pp. 117864692097090
Author(s):  
Abid Bhat ◽  
Ananda Staats Pires ◽  
Vanessa Tan ◽  
Saravana Babu Chidambaram ◽  
Gilles J Guillemin

Sleep has a regulatory role in maintaining metabolic homeostasis and cellular functions. Inadequate sleep time and sleep disorders have become more prevalent in the modern lifestyle. Fragmentation of sleep pattern alters critical intracellular second messengers and neurotransmitters which have key functions in brain development and behavioral functions. Tryptophan metabolism has also been found to get altered in SD and it is linked to various neurodegenerative diseases. The kynurenine pathway is a major regulator of the immune response. Adequate sleep alleviates neuroinflammation and facilitates the cellular clearance of metabolic toxins produced within the brain, while sleep deprivation activates the enzymatic degradation of tryptophan via the kynurenine pathway, which results in an increased accumulation of neurotoxic metabolites. SD causes increased production and accumulation of kynurenic acid in various regions of the brain. Higher levels of kynurenic acid have been found to trigger apoptosis, leads to cognitive decline, and inhibit neurogenesis. This review aims to link the impact of sleep deprivation on tryptophan metabolism and associated complication in the brain.


2013 ◽  
Vol 6 ◽  
pp. IJTR.S12797 ◽  
Author(s):  
Rowland R. Noakes

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 the urinary excretion of the kynurenine metabolites kynurenic and quinolinic acid under condition of L tryptophan loading in a volunteer. Mean baseline value for kynurenic acid and quinolinic acid were 1.1 and 2.1 mmol/mol creatinine, respectively. This rose to 5.6 and 3.8 mmol/mol creatinine respectively under conditions of L tryptophan loading 2 grams daily. Adding 1 g of tranilast daily lowered the values to 2.0 and 2.9 mmol/mol creatinine, respectively. These data suggest that tranilast acts as a competitive inhibitor of either indoleamine 2, 3-dioxygenase (IDO), tryptophan 2, 3 di-oxygenase (TDO) or both. As it involved only 1 subject, the results may not be representative of the larger population and must be considered preliminary.


2019 ◽  
Vol 16 (1) ◽  
Author(s):  
Pratishtha Chatterjee ◽  
Henrik Zetterberg ◽  
Kathryn Goozee ◽  
Chai K. Lim ◽  
Kelly R. Jacobs ◽  
...  

Abstract Background Blood markers indicative of neurodegeneration (neurofilament light chain; NFL), Alzheimer’s disease amyloid pathology (amyloid-β; Aβ), and neuroinflammation (kynurenine pathway; KP metabolites) have been investigated independently in neurodegenerative diseases. However, the association of these markers of neurodegeneration and AD pathology with neuroinflammation has not been investigated previously. Therefore, the current study examined whether NFL and Aβ correlate with KP metabolites in elderly individuals to provide insight on the association between blood indicators of neurodegeneration and neuroinflammation. Methods Correlations between KP metabolites, measured using liquid chromatography and gas chromatography coupled with mass spectrometry, and plasma NFL and Aβ concentrations, measured using single molecule array (Simoa) assays, were investigated in elderly individuals aged 65–90 years, with normal global cognition (Mini-Mental State Examination Score ≥ 26) from the Kerr Anglican Retirement Village Initiative in Ageing Health cohort. Results A positive correlation between NFL and the kynurenine to tryptophan ratio (K/T) reflecting indoleamine 2,3-dioxygenase activity was observed (r = .451, p < .0001). Positive correlations were also observed between NFL and kynurenine (r = .364, p < .0005), kynurenic acid (r = .384, p < .0001), 3-hydroxykynurenine (r = .246, p = .014), anthranilic acid (r = .311, p = .002), and quinolinic acid (r = .296, p = .003). Further, significant associations were observed between plasma Aβ40 and the K/T (r = .375, p < .0005), kynurenine (r = .374, p < .0005), kynurenic acid (r = .352, p < .0005), anthranilic acid (r = .381, p < .0005), and quinolinic acid (r = .352, p < .0005). Significant associations were also observed between plasma Aβ42 and the K/T ratio (r = .215, p = .034), kynurenic acid (r = .214, p = .035), anthranilic acid (r = .278, p = .006), and quinolinic acid (r = .224, p = .027) in the cohort. On stratifying participants based on their neocortical Aβ load (NAL) status, NFL correlated with KP metabolites irrespective of NAL status; however, associations between plasma Aβ and KP metabolites were only pronounced in individuals with high NAL while associations in individuals with low NAL were nearly absent. Conclusions The current study shows that KP metabolite changes are associated with biomarker evidence of neurodegeneration. Additionally, the association between KP metabolites and plasma Aβ seems to be NAL status dependent. Finally, the current study suggests that an association between neurodegeneration and neuroinflammation manifests in the periphery, suggesting that preventing cytoskeleton cytotoxicity by KP metabolites may have therapeutic potential.


Blood ◽  
2021 ◽  
Vol 138 (Supplement 1) ◽  
pp. 3895-3895
Author(s):  
Orsatti Laura ◽  
Thomas Stiehl ◽  
Katharina Dischinger ◽  
Roberto Speziale ◽  
Pamela Di Pasquale ◽  
...  

Abstract Background: Fibrosing chronic graft-versus-host disease (cGVHD) is a debilitating complication after allogeneic stem cell transplantation (allo-SCT), and its pathophysiology is poorly understood. Kynurenine and its metabolites were shown to associate with both, interferon-gamma (IFNg) activation and fibrosis. This study investigates the interplay between members of the IFNγ pathway and Kynurenin-derived metabolites in cGVHD. Methods: Using a liquid chromatography tandem mass spectrometry approach on sera obtained on day+100 (n=430) and/or at onset of cGVHD symptoms (n=196) of our prospectively collected biobank after alloSCT, we measured concentrations of Kyn pathway metabolites (kynurenin (Kyn), anthranilic acid (AA), kynurenic acid (KA), 3-hydroxykynurenine (3-HK), and 3-hydroxy-anthranilic acid (3-HAA). We also measured C-X-C chemokine ligand 9 (CXCL9), interleukin (IL-)18, tryptophane (Trp) and indoleamine-2,3-dioxygenase (IDO) by ELISA. Results: We observed increased CXCL9 and IDO levels, and increased activity of the Kynurenine pathway in both non-severe and severe cGVHD. Interestingly, severe fibrosing cGVHD differed from any other form of cGVHD in a significant pathway shift toward AA and KA. This resulted in a reduced 3-HAA/AA ratio. A score consisting of low 3-HAA/AA ratio and high KA serum levels at onset of mild cGVHD symptoms predicted risk specifically of severe fibrosing cGVHD. This altered pathway in severe fibrosing cGVHD correlated with reduced activity of the Vitamin-B2-dependent kynurenine monooxygenase, low vitamin B6, and increased interleukin-18. Our results are consistent with a triple-hit model for fibrosing cGVHD including low activity of kynurenine monooxygenase (KMO, Vitamin B2 and B6 dependent) in the context of high IL18 serum levels and CXCL9-induced IDO activation (Figure 1). Conclusion: Chronic GVHD associates with an IFNg signature and increased activity of the Kynurenin pathway. KA and 3-HAA/AA defined the first molecular distinction between fibrosing and non-fibrosing cGVHD. The mechanism may involve Vitamin B2/B6 deficiency, and high CXCL9 and IL18. The Kyn metabolite signature is a candidate biomarker for severe fibrosing cGHVD and provides a rationale for translational trials on prophylactic Vitamin B2/B6 supplementation for cGVHD prevention. Figure 1: Triple hit model of fibrosing cGVHD (Hypothesis): Severe fibrosing cGVHD associates with a strong CXCL9-induced activation of IDO. The result of this activation is influenced by a reduced activity of kynurenine monooxygenase (KMO), either due to genetic polymorphisms or lack of Vitamin B2, and further aggravated by lack of Vitamin B6. The resulting metabolic deviation increases AA concentrations and reduces the 3-HAA/AA ratio. Finally, high IL-18 associates with increased serum KA. These three hits result in a metabolic situation with high KA and a low ratio 3-HAA/AA that predicts risk of fibrosing cGVHD. Figure 1 Figure 1. Disclosures Mueller-Tidow: Janssen Cilag: Consultancy, Research Funding; Pfizer: Consultancy, Research Funding; Bioline: Consultancy, Research Funding.


2016 ◽  
Vol 9 ◽  
pp. IJTR.S38190 ◽  
Author(s):  
Abdulla A.-B. Badawy ◽  
Samina Bano

Rat liver tryptophan (Trp), kynurenine pathway metabolites, and enzymes deduced from product/substrate ratios were assessed following acute and/or chronic administration of kynurenic acid (KA), 3-hydroxykynurenine (3-HK), 3-hydroxyanthranilic acid (3-HAA), Trp, and the kynureninase inhibitors benserazide (BSZ) and carbidopa (CBD). KA activated Trp 2,3-dioxygenase (TDO), possibly by increasing liver 3-HAA, but inhibited kynurenine aminotransferase (KAT) and kynureninase activities with 3-HK as substrate. 3-HK inhibited kynureninase activity from 3-HK. 3-HAA stimulated TDO, but inhibited kynureninase activity from K and 3-HK. Trp (50 mg/kg) increased kynurenine metabolite concentrations and KAT from K, and exerted a temporary stimulation of TDO. The kynureninase inhibitors BSZ and CBD also inhibited KAT, but stimulated TDO. BSZ abolished or strongly inhibited the Trp-induced increases in liver Trp and kynurenine metabolites. The potential effects of these changes in conditions of immune activation, schizophrenia, and other disease states are discussed.


1987 ◽  
Vol 2 (2) ◽  
pp. 95-100
Author(s):  
Adolf L. Pohl

A novel ADP-ribosyltransferase (ADPRT) is reported from sera of both healthy human subjects (n = 25) and patients with colorectal tumors (n = 12) and breast cancer (n = 55). In sera of healthy controls (n = 25) the average ADPRT values were 250 ± 56 picokatal/liter. ADPRT serum activities in metastatic cancer patients (n = 47) were three times higher (p < 0.01) than in normal controls. A tumor origin of the serum ADPRT can be inferred from the statistical correlation (R = 0.74) between tumor and serum levels. The radiometric test procedure (CV 20–25%) is critically validated and kinetic properties of serum ADPRT have been studied, showing a competitive inhibition by nicotinamide, benzamide and 3-aminobenzamide. The kinetic parameters of serum ADPRT resemble those reported for nuclear ADPRT, thus indicating that serum ADPRT activity could be due to a nuclear enzyme released from the tumor cells.


2011 ◽  
Vol 9 (2) ◽  
pp. 65-73
Author(s):  
Gennady A Zakharov ◽  
Alexander V Zhuravlev ◽  
Tatyana L Payalina ◽  
Nikolay G Kamyshev ◽  
Elena V Savvateeva-Popova

Disbalance of kynurenines produced by Drosophila mutations of the kynurenine pathway of tryptophan metabolism influences the locomotor behavior in larvae. The most pronounced is the effect of accumulation of kynurenic acid in the mutant cinnabar manifested as sharp reduction of general level of locomotor activity. The mutations seem to act through modulatory influences of kynurenines on signal cascades governed by ionotropic glutamatergic and cholinergic receptors. Expression of receptor genes in the mutants shows age-related changes pointing to gradual evolvement of consequences of kynurenines disbalance.


2014 ◽  
Vol 222 (3) ◽  
pp. 171-178 ◽  
Author(s):  
Mareile Hofmann ◽  
Nathalie Wrobel ◽  
Simon Kessner ◽  
Ulrike Bingel

According to experimental and clinical evidence, the experiences of previous treatments are carried over to different therapeutic approaches and impair the outcome of subsequent treatments. In this behavioral pilot study we used a change in administration route to investigate whether the effect of prior treatment experience on a subsequent treatment depends on the similarity of both treatments. We experimentally induced positive or negative experiences with a topical analgesic treatment in two groups of healthy human subjects. Subsequently, we compared responses to a second, unrelated and systemic analgesic treatment between both the positive and negative group. We found that there was no difference in the analgesic response to the second treatment between the two groups. Our data indicate that a change in administration route might reduce the influence of treatment history and therefore be a way to reduce negative carry-over effects after treatment failure. Future studies will have to validate these findings in a fully balanced design including larger, clinical samples.


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