Relationship between metabolites of peripheral tryptophan-kynurenine metabolic pathway and clinical symptoms in patients with schizophrenia / 四川精神卫生

BackgroundSchizophrenia is a common severe mental disorder with complex pathogenesis. There are few studies on the correlation between kynurenine metabolites in peripheral serum and urine in schizophrenia. ObjectiveTo investigate the concentration of tryptophan-kynurenine metabolites and interleukin-6 （IL-6） in serum and urine in patients with schizophrenia， and their correlation with clinical symptoms， so as to explore potential biological characteristics related to schizophrenia. MethodsA total of 38 patients with schizophrenia who met the criteria of the Diagnostic and Statistical Manual of Mental Disorders， fifth edition （DSM-5）， and were hospitalized or attended outpatient clinic at Hangzhou Seventh People's Hospital from December 2021 to December 2022 were included in the study. Additionally， 26 healthy individuals were concurrently recruited from the community of Hangzhou to serve as a control group. All participants were requested to complete the Positive and Negative Symptom Scale （PANSS）. The levels of tryptophan （TRP）， kynurenine （KYN）， kynurenic acid （KYNA）， quinolinic acid （QUIN）， picolinic acid （PIC）， xanthurenate and 5-hydroxytryptamine （5-HT） in both serum and urine were measured using ultra-high-performance liquid chromatography-triple quadrupole linear ion trap mass spectrometry. Serum and urine IL-6 were measured using enzyme-linked immunosorbent assay. Pearson correlation analysis was conducted to examine the correlation between serum and urinary KYN metabolites， as well as the correlation between metabolite levels and clinical symptoms in the patient group. ResultsPatients with schizophrenia had significantly higher level of IL-6 in serum （U=798.500， P<0.01） and lower level of PIC in urine （U=253.000， P=0.013） compared with the control group. Additionally， level of serum KYN was positively correlated with QUIN/KYNA ratio and QUIN/PIC ratio （r=0.562， 0.438， P<0.05） in patients with schizophrenia. 5-HT/KYN ratio in serum was positively correlated with PANSS total score and negative symptom subscale score （r=0.458， 0.455， P<0.01） in patients with schizophrenia. ConclusionSerum TRP-KYN pathway metabolite levels in patients with schizophrenia were associated with neurotoxic metabolite ratios in urine and the severity of negative symptoms. ［Funded by Zhejiang Medical and Health Science and Technology Program Exploratory （number， 2022KY990）］

Confirmación de la presencia de células serotoninérgicas en la corteza cerebral fetal en cultivos e in situ / Confirmation of the presence of serotonergic cells in the fetal cerebral cortex in cultures and in situ

Resumen Antecedentes: La aparición temprana de serotonina en el cerebro fetal y sus efectos en la morfogénesis cerebral apoyan su papel neurotrófico. Objetivo: Determinar la presencia de células serotoninérgicas y la expresión de triptófano-5-hidroxilasa (TPH), 5-hidroxitriptamina (5-HT), transportador de serotonina (SERT), receptor 5-HT1A y Pet-1 durante el desarrollo de la corteza cerebral, tanto in situ como en cultivo de tejidos. Material y métodos: Se realizó estudio observacional descriptivo en ratas Wistar preñadas. La presencia del tapón se consideró el inicio de la gestación; en los días 13, 16 y 17 se practicaron cesáreas para obtener los fetos e inmediatamente se disecaron los cerebros para identificar células serotoninérgicas, TPH, 5-HT, SERT, 5-HT1A y Pet-1 en cultivo de tejido e in situ mediante inmunomarcaje detectado en un microscopio confocal. Resultados: Células y terminales serotoninérgicas fueron observadas en el mesencéfalo el día 17 de gestación y en cocultivos de neopalio los días 13 y 16. También se observaron células inmunopositivas a TPH, 5-HT, SERT y Pet-1 en el neopalio en el día 12 del cultivo. Conclusiones: Se confirmó la presencia de células serotoninérgicas y otros elementos del sistema serotoninérgico en la corteza cerebral temprana, la cual puede ser transitoria y participar en los procesos de maduración cortical durante el desarrollo cerebral.

Abstract Background: Early appearance of serotonin in the fetal brain and its effects on brain morphogenesis support its neurotrophic role. Objective: To determine the presence of serotonergic cells and the expression of tryptophan-5-hydroxylase (TPH), 5-hydroxytryptamine (5-HT), serotonin transporter (SERT), 5-HT1A receptor and Pet-1 during the development of the cerebral cortex, both in situ and in tissue cultures. Material and methods: A descriptive, observational study was carried out in pregnant Wistar rats. The presence of the plug was regarded as the beginning of gestation. On days 13, 16 and 17, cesarean sections were performed to obtain the fetuses, and the brains were then immediately dissected to identify the presence of serotonergic cells, TPH, 5-HT, SERT, 5-HT1A and Pet-1 in tissue cultures and in situ by immunostaining detected on a confocal microscope. Results: Serotonergic cells and terminals were observed in the midbrain on day 17 of gestation, and in neopallium cocultures on days 13 and 16. TPH, 5-HT, SERT and Pet-1 immunopositive cells were also observed in the neopallium on day 12 of culture. Conclusions: The presence of serotonergic cells and other elements of the serotonergic system in the early cerebral cortex was confirmed, which may be transient and participate in cortical maturation processes during brain development.

The kynurenine pathway in major depressive disorder, bipolar disorder, and schizophrenia: a systematic review and meta-analysis of cerebrospinal fluid studies

Objectives: The kynurenine (KYN) pathway has been attracting attention as a relevant pathway in schizophrenia (SZ), bipolar disorder (BD), and major depressive disorder (MDD). We conducted a systematic review and meta-analysis of studies examining KYN pathway metabolites from cerebrospinal fluid (CSF) samples in SZ, BD, and MDD. Methods: The PubMed and Scopus databases were systematically searched to identify peer-reviewed case-control studies published until April 2022 that assessed KYN metabolites, namely, tryptophan (TRP), KYN, kynurenic acid (KA), quinolinic acid (QA), and 3-hydroxykynurenine (3-HK), in subjects with SZ, BD, or MDD compared with healthy controls (HC). The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines were followed. The random effects model method was selected for comparison of standardized mean differences (SMD) between two groups. Results: Twenty-three articles met the inclusion criteria (k = 8, k = 8, k = 11, for SZ, BD, and MDD, respectively). In SZ, KA levels were increased (SMD = 2.64, confidence interval [CI] = 1.16 to 4.13, p = 0.0005, I2 = 96%, k = 6, n=384). TRP (k = 5) and KYN (k = 4) did not differ significantly. In BD, TRP levels (k = 7) did not differ significantly. The level of KA was increased in MDD (k = 2), but the small number of studies precluded evaluation of statistical significance. Finally, in MDD, although some studies tended to show an increased level of KYN in those with remission vs. decreased levels in those with current depression, no significant difference was found in any KYN metabolite levels. Similarly, an increased level of QA was found, but the number of studies (k = 2) was small. Conclusion: KA, which has possibly neuroprotective effects, is increased in SZ. QA, which has neurotoxic effects, may be increased in MDD. There were no alterations in BD. Alterations in the KYN pathway may occur based on population characteristics and mood states. Future studies should explore the utility of these metabolites as biomarkers.

The kynurenine pathway in Alzheimer's disease: a meta-analysis of central and peripheral levels

Objective: Changes in the kynurenine pathway are recognized in psychiatric disorders, but their role in Alzheimer's disease (AD) is less clear. We aimed to conduct a systematic review and meta-analysis to determine whether tryptophan and kynurenine pathway metabolites are altered in AD. Methods: We performed a systematic review and random-effects meta-analyses. Inclusion criteria were studies that compared AD and cognitively normal (CN) groups and assessed tryptophan or kynurenine pathway metabolites in cerebrospinal fluid or peripheral blood. Results: Twenty-two studies with a total of 1,356 participants (664 with AD and 692 CN individuals) were included. Tryptophan was decreased only in peripheral blood. The kynurenine-to-tryptophan ratio was only increased in peripheral blood of the AD group. 3-Hydroxykynurenine was decreased only in cerebrospinal fluid and showed higher variability in the CN group than the AD group. Kynurenic acid was increased in cerebrospinal fluid and decreased in peripheral blood. Finally, there were no changes in kynurenine and quinolinic acid between the groups. Conclusions: Our results suggested a shift toward the kynurenine pathway in both the brain and in the periphery, as well as a shift towards increased kynurenic acid production in the brain but decreased production in peripheral blood. In addition, our analysis indicated dissociation between the central and peripheral levels, as well as between plasma and serum for some of these metabolites. Finally, changes in the kynurenine pathway are suggested to be a core component of AD. More studies are warranted to verify and consolidate our results.

Mechanism of tryptanthrin in treatment of ulcerative colitis in mice based on serum metabolomics / 中国中药杂志

This study aims to explore the effect of tryptanthrin on potential metabolic biomarkers in the serum of mice with ulcerative colitis(UC) induced by dextran sulfate sodium(DSS) based on liquid chromatography-mass spectrometry(LC-MS) and predict the related metabolic pathways. C57BL/6 mice were randomly assigned into a tryptanthrin group, a sulfasalazine group, a control group, and a model group. The mouse model of UC was established by free drinking of 3% DSS solution for 11 days, and corresponding drugs were adminsitrated at the same time. The signs of mice were observed and the disease activity index(DAI) score was recorded from the first day. Colon tissue samples were collected after the experiment and observed by hematoxylin-eosin(HE) staining. The levels of interleukin-4(IL-4), interleukin-10(IL-10), tumor necrosis factor-α(TNF-α), interleukin-6(IL-6), and interleukin-8(IL-8) in the serum were measured by enzyme linked immunosorbent assay(ELISA). The serum samples were collected from 6 mice in each group for widely targeted metabolomics. The metabolic pathways were enriched by MetaboAnalyst 5.0. The results showed that compared with the model group, tryptanthrin treatment decreased the DAI score(P<0.05), alleviated the injury of the colon tissue and the infiltration of inflammatory cells, lowered the levels of proinflammatory cytokines, and elevated the levels of anti-inflammatory cytokines in the serum. The metabolomic analysis revealed 28 differential metabolites which were involved in 3 metabolic pathways including purine metabolism, arachidonic acid metabolism, and tryptophan metabolism. Tryptanthrin may restore the metabolism of the mice with UC induced by DSS to the normal level by regulating the purine metabolism, arachidonic acid metabolism, and tryptophan metabolism. This study employed metabolomics to analyze the mechanism of tryptanthrin in the treatment of UC, providing an experimental basis for the utilization and development of tryptanthrin.

Modular engineering of Escherichia coli for high-level production of l-tryptophan / 生物工程学报

As an essential amino acid, l-tryptophan is widely used in food, feed and medicine sectors. Nowadays, microbial l-tryptophan production suffers from low productivity and yield. Here we construct a chassis E. coli TRP3 producing 11.80 g/L l-tryptophan, which was generated by knocking out the l-tryptophan operon repressor protein (trpR) and the l-tryptophan attenuator (trpL), and introducing the feedback-resistant mutant aroGfbr. On this basis, the l-tryptophan biosynthesis pathway was divided into three modules, including the central metabolic pathway module, the shikimic acid pathway to chorismate module and the chorismate to tryptophan module. Then we used promoter engineering approach to balance the three modules and obtained an engineered E. coli TRP9. After fed-batch cultures in a 5 L fermentor, tryptophan titer reached to 36.08 g/L, with a yield of 18.55%, which reached 81.7% of the maximum theoretical yield. The tryptophan producing strain with high yield laid a good foundation for large-scale production of tryptophan.

Linderae Radix water extract treats diarrhea-predominant irritable bowel syndrome in rats: a serum metabolomics study / 中国中药杂志

This study aims to investigate the mechanism of Linderae Radix water extract(LRWE) in the prevention and treatment of diarrhea-predominant irritable bowel syndrome(IBS-D) based on serum metabolomics. Eighteen 2-week-old male SD rats were randomized into control, IBS-D model, and LRWE groups. The rats in other groups except the control group received gavage of senna concentrate combined with restraint stress for the modeling of IBS-D. The rats in the LRWE group were administrated with LRWE(5.4 g·kg~(-1)) by gavage, and those in the control and IBS-D model groups with an equal volume of distilled water for a total of 14 days. The visceral sensitivity was evaluated by the abdominal withdrawal reflex(AWR) score, and the degree of diarrhea was assessed by the fecal water content(FWC). The morphological changes of the colon and the morphology and number of goblet cells were observed by hematoxylin-eosin(HE) and periodic acid-schiff(PAS) staining, respectively. Ultra-high performance liquid chromatography-tandem mass spectrometry(UPLC-MS/MS) was used for the screening of the potential biomarkers in the rat serum and their related metabolic pathways. The results showed that LRWE reduced the AWR score, decreased FWC, and alleviated visceral sensitivity and diarrhea symptoms in IBS-D rats. HE and PAS staining showed that LRWE mitigated low-grade intestinal inflammation and increased the number of mature secretory goblet cells in the colonic epithelium of IBS-D rats. A total of 25 potential biomarkers of LRWE in treating IBS-D were screened out in this study, which were mainly involved in riboflavin, tryptophan, glycine, serine and threonine metabolism, glyoxylate and dicarboxylate metabolism, and cysteine and methionine metabolism. The regulatory effects were the most significant on the riboflavin and tryptophan metabolism pathways. LRWE may alleviate the visceral hypersensitivity by promoting energy metabolism and amino acid metabolism, enhancing intestinal barrier function, and improving intestinal immune function in IBS-D rats.

Effects of moxibustion on behaviors and tryptophan metabolism-related products in mice with irritable bowel syndrome / 针灸推拿医学（英文版）

Objective: To observe the effect of moxibustion on behaviors and related products of tryptophan (Trp) metabolism in the colon of mice with irritable bowel syndrome (IBS), and to explore the mechanism of moxibustion in the IBS treatment.Methods: Twenty-four mice were randomly divided into a normal group, a model group, a moxibustion group, and a probiotic group, with 6 mice in each group. The visceral pain model of IBS was established by enema with 2,4,6-trinitrobenzene sulfonic acid (TNBS) solution. Mice in the moxibustion group were treated with mild moxibustion at bilateral Zusanli (ST36), and those in the probiotic group were treated with probiotics such as Bifidobacterium by gavage. Abdominal withdrawal reflex (AWR) test, elevated plus-maze (EPM) test, and forced swimming test (FST) were performed after treatment. The expression levels of 5-hydroxytryptamine (5-HT) and tryptophan hydroxylase 1 (TPH1) in the colon were detected by immunofluorescence, and the expression levels of Trp, kynurenine (Kyn), and indole-2,3-oxygenase (IDO) in the colon were detected by enzyme-linked immunosorbent assay. Results: Compared with the normal group, the AWR scores were increased significantly in the model group under different pressure values (P<0.01), the open-arm staying time and open-arm entries in the EPM test were decreased significantly (P<0.01, P<0.05), the motionless time in the FST was increased significantly (P<0.01), and the expression levels of colonic Trp, TPH1, IDO, 5-HT, and Kyn were increased significantly (P<0.01) in the models. Compared with the model group, the AWR scores were differently decreased (P<0.05 or P<0.01), the open-arm entries in the EPM test were increased (P<0.05), the motionless times in the FST were decreased (P<0.05), and the colonic expression levels of Trp, TPH1, IDO, and 5-HT were decreased (P<0.01 or P<0.05) in the moxibustion and probiotic groups; the open-arm staying time was significantly increased in the moxibustion group (P<0.01), and the colonic expression level of Kyn was significantly decreased in the probiotic group (P<0.01). Conclusion: Moxibustion at Zusanli (ST36) improves visceral pain and pain mood and down-regulates the expression levels of colonic TPH1, IDO, Trp, 5-HT, and Kyn in IBS mice.

Development and validation of ID-LC-MS/MS method for L-tryptophan and its metabolites / 中华检验医学杂志

Objective:To establish an isotope dilution liquid chromatography-tandem mass spectrometry (ID-LC-MS/MS) method for the determination of L-tryptophan and its metabolites in serum.Methods:The methodology was established and evaluated using serum samples collected from 166 healthy subjects undergoing physical examinations at West China Hospital from November 2022 to January 2023 were collected. Isotope-labeled markers of L-tryptophan (Trp), L-kynurenine (Kyn), and kynurenic acid (KA) were used as internal standards. After protein precipitation treatment of serum samples, LC-MS/MS was used to determine Trp, Kyn, and KA simultaneously. The selectivity, specificity, linearity, detection limit (LOD), quantification limit (LOQ), carry-over, precision, recovery rate, matrix effect, and dilution integrity of the method were evaluated.Results:The linearity of Trp, Kyn, and KA was demonstrated to be 0.999. The LODs were 0.10 μmol/L, 0.01 μmol/L and 1.00 nmol/L, respectively. The LOQs were 0.20 μmol/L, 0.04 μmol/L and 2.00 nmol/L, respectively. The intra-batch precision and inter-batch precision were below<10%. The average recovery rate and the relative matrix effect were all about 100%. The samples over the upper limit of quantitation can be diluted up to 16 times. The Trp concentration, Kyn concentration, KA concentration, Kyn/Trp ratio, and KA/Kyn ratio in serum of healthy subjects were 59.55±10.92 μmol/L, 1.85±0.43 μmol/L, 39.89±17.93 nmol/L, (31.64±8.19)×10 -3 and 21.51±6.72, respectively. Conclusion:An ID-LC-MS/MS method was successfully established for the quantitative determination of Trp, Kyn, and KA in serum. The method proved to be simple, rapid, sensitive, accurate, and reliable, providing robust support for clinical research related to these analytes.

Breastfeeding and infant sleep:a review / 中国实用护理杂志

Sufficient and organized sleep is a key factor during the developmental process of infancy while disrupted sleep schedule and diseases might lead to sleeping disorders in infants. Breastfeeding is considered to be the most beneficial way to meet the nutritional needs of infants for optimal growth and development. The α-lactalbumin-tryptophan-melatonin axis, nucleotides, and other factors are breast milk components that may affect infant sleep. Meanwhile, diet, feeding schedule, tobacco smoking, alcohol intake, and caffeine consumption will affect the circadian rhythms which might lead to the fluctuations of sleep-influencing factors in breast milk. This study reviews literature of previous studies on this topic to summarize information that can be considered for both breastfeeding practice and future basic research on the establishment of organized sleep patterns in infants.

La miocardiopatía hipertrófica induce cambios en la expresión de la triptófano-5-hidroxilasa, el transportador de serotonina y receptores serotoninérgicos / Hypertrophic cardiomyopathy induces changes in the tryptophan-5-hydroxylase, serotonin transporter and serotonergic receptors expressions

Resumen Introducción: Los cardiomiocitos poseen la maquinaria bioquímica capaz de sintetizar, utilizar y recapturar serotonina. Objetivo: Determinar si la miocardiopatía hipertrófica (MCH) induce cambios en la expresión de la triptófano-5-hidroxilasa (TPH) 1 y 2, el transportador de serotonina (SERT) y los receptores serotoninérgicos (RS). Métodos: Estudio transversal de cinco bloques de tejido de corazones con MCH y cinco bloques de corazones de control. Se obtuvieron cinco cortes de la pared libre del ventrículo izquierdo (PLVI) y del septum interventricular (SIV) de cada bloque, para determinar la expresión de TPH1 y TPH2, SERT y RS con anticuerpos por inmunofluorescencia. La inmunofluorescencia fue evaluada mediante t de WELCH, con nivel de significación de p < 0.05. Resultados: La PLVI y el SIV de los corazones con MCH mostraron aumento de la expresión de TPH1 y TPH2, así como de los receptores 5-HT2A y 5-HT2B en comparación con los controles (p < 0.01). El receptor 5-HT4 y SERT aumentaron en el SIV de los corazones con MCH (p < 0.01). Conclusiones: Se demostró aumento de las expresiones de TPH, SERT y RS en los cardiomiocitos de los corazones con MCH en comparación con los controles, lo cual podría participar en la fisiopatología de la MCH en los humanos.

Abstract Introduction: Cardiomyocytes have a biochemical machinery with the capacity to synthesize, utilize and reuptake serotonin. Objective: To determine whether hypertrophic cardiomyopathy (HCM) induces changes in the expression of tryptophan-5-hydroxylase (TPH) 1 and 2, serotonin transporter (SERT) and serotonergic receptors (SR). Methods: Cross-sectional study of five tissue blocks from hearts with HCM and five controls. Five sections of the left ventricular free wall (LVFW) and interventricular septum (IVS) were obtained from each block to determine the expression of TPH1 and TPH2, SERT and SRs by immunofluorescence with specific antibodies. Immunofluorescence was evaluated by WELCH t-test, with a level of significance of p < 0.05. Results: LVFW and IVS of hearts with HCM showed an increase in the expression of TPH1 and TPH 2 and 5-HT2A and 5-HT2B receptors in comparison with controls (p < 0.01). The 5-HT4 receptor and SERT showed an increase in the IVS of hearts with HCM (p < 0.01). Conclusions: This study demonstrated an increased expression of TPH, SERT and SRs in cardiomyocytes from hearts with HCM in comparison with controls, which could be involved in the pathophysiology of HCM in humans.

Cambios en la actividad y expresión de las triptófano-5-hidroxilasas cerebrales y en el número de neuronas serotoninérgicas por la diabetes mellitus, que no retornan a la normalidad con la insulina / Diabetes mellitus causes changes in brain tryptophan-5-hydroxylases activity and expression and in the number of serotonergic neurons, which do not return to normal with insulin treatment

Resumen Introducción: La diabetes mellitus (DM) inhibe la biosíntesis de serotonina cerebral mediante cambios en la actividad y expresión de triptófano-5-hidroxilasa (TPH). Objetivos: Determinar si los cambios en la expresión de TPH1 y TPH2 cerebral y en el número de neuronas serotoninérgicas causados por la DM retornan a la normalidad en ratas con diabetes tratadas con insulina. Métodos: Ratas con diabetes inducida con estreptozotocina se dividieron en dos grupos uno tratado con insulina y otro sin tratamiento. En el día 14, se obtuvieron tallos cerebrales para cuantificar niveles de L-triptófano, 5-hidroxitriptamina y la actividad de la TPH. La expresión de TPH1 y TPH2 fue mediante Western blot y el número de neuronas serotoninérgicas por inmunohistoquímica. Resultados: En las ratas con diabetes se confirmó disminución de los niveles de L-triptófano, 5-hidroxitriptamina y la actividad de la TPH, así como menor expresión de TPH1 y TPH2 y menor número de neuronas serotoninérgicas. Cuando las ratas diabéticas fueron tratadas con insulina, el L-triptófano regresó a la normalidad, no así la 5-hidroxitriptamina, la expresión de TPH ni el número de neuronas serotoninérgicas. Conclusiones: La DM inhibe crónicamente la síntesis de 5-hidroxitriptamina cerebral mediante modificaciones en la expresión de TPH1 y TPH2 y disminución de las neuronas serotoninérgicas, que persisten a pesar del tratamiento con insulina.

Abstract Introduction: Diabetes mellitus (DM) inhibits brain serotonin biosynthesis through changes in tryptophan-5-hydroxylase (TPH) activity and expression. Objectives: To determine whether DM-induced changes in brain TPH1 and TPH2 expression and in the number of serotonergic neurons return to normal in diabetic rats treated with insulin. Methods: Rats with streptozotocin-induced diabetes were divided in two groups: one treated with insulin and the other without treatment. On day 14, brain stems were obtained in order to quantify L-tryptophan and 5-hydroxytryptamine levels, as well as to determine TPH activity. The expressión of TPH1 and THP2 by Western blot, and the number of serotonergic neurons by immunohistochemistry. Results: In diabetic rats, a decrease in the levels of L-tryptophan, 5-hydroxytryptamine and TPH activity was confirmed, as well as lower TPH1 and TPH2 expression and lower numbers of serotonergic neurons. When diabetic rats were treated with insulin, L-tryptophan returned to normal, but not 5-hydroxytryptamine, TPH expression, or the number of serotonergic neurons. Conclusions: DM chronically inhibits the synthesis of brain 5-hydroxytryptamine through changes in TPH1 and TPH2 expression and a decrease in the number of serotonergic neurons, which persist despite insulin treatment.

Desenvolvimento de bebidas lácteas probióticas adicionadas de polpa de morango e suplementadas com L-triptofano elaboradas a partir de leite bubalino e bovino / Development of probiotic dairy beverages with strawberry pulp and supplemented with L-tryptophan from buffalo and bovine milk

O objetivo deste estudo foi desenvolver uma formulação de bebida láctea bubalina probiótica adicionada de polpa de morango, comparando os efeitos do uso do leite de búfala e de vaca na elaboração dos produtos e verificando a possibilidade de suplementação com triptofano nos produtos lácteos probióticos. Como primeira etapa do trabalho, bebidas lácteas probióticas foram elaboradas a partir de leite bubalino e bovino, fermentadas com Streptococcus thermophilus TA040, Lactobacillus bulgaricus LB340 e Lactobacillus acidophilus La5, e formuladas com 0, 25 e 50% de soro em sua formulação. As bebidas foram avaliadas quanto à cinética de fermentação das culturas láticas utilizadas, ao teor de proteína, gordura e sólidos totais não gordurosos, pós-acidificação, viabilidade das culturas fermentadoras e sua capacidade de sobrevivência ao estresse gastrointestinal in vitro. As bebidas lácteas bubalinas apresentaram resultados superiores as bebidas bovinas. O uso do leite de búfala na elaboração das bebidas lácteas promoveu benefícios quanto as culturas láticas presentes nos produtos, exercendo efeito protetivo e influindo na preservação da viabilidade das bactérias ao longo do armazenamento refrigerado e durante a simulação do estresse gastrointestinal in vitro. As bebidas lácteas elaboradas com 25% apresentaram os resultados mais próximos aos obtidos pelos produtos controle, sem adição de soro, sendo selecionadas para a segunda parte do estudo. Nesta etapa, as formulações de bebida láctea com 25% de soro, foram acrescidas de um preparado com polpa de morango e bebidas sem adição da fruta, utilizadas como controle. As bebidas lácteas bubalinas frutadas, apresentaram menor teor de gordura e melhores características reológicas, com maior viscosidade e consistência do que os produtos controle, sem afetar a pós-acidificação, o perfil de ácido graxo, assim como, a viabilidade e a resistência às condições de estresse gastrointestinal in vitro das culturas fermentadoras. A avaliação da possibilidade de suplementar lácteos probióticos com triptofano foi realizada em conjunto com a Universidade de Milão. Para isso, iogurtes probióticos receberam adição de triptofano antes ou após a fermentação, sendo avaliados com relação ao perfil de pós-acidificação, quantidade de triptofano nos produtos, número de células viáveis por plaqueamento e citometria de fluxo ao longo do armazenamento a 25° e 4°C. Complementarmente, a influência da presença do triptofano no crescimento e produção de compostos antimicrobianos pelas culturas láticas, também foi avaliada. A adição de triptofano após a fermentação dos iogurtes, que foram armazenados sob refrigeração (4°C), além de não afetar a pós-acidificação dos produtos, apresentou benefícios quanto a viabilidade L. acidophilus, redução do dano e aumento do número de células vivas, promovendo teor maior do aminoácido nos iogurtes. A presença do triptofano nos meios de cultivo, também influenciou de forma positiva o crescimento de S. thermophilus e L. acidophilus, melhorando o desenvolvimento das bactérias durante a fermentação e influindo em uma maior atividade antilistérica por parte do S. thermophilus. Diante da influência positiva da aplicação do leite de búfala na elaboração das bebidas lácteas, assim como, a adição do triptofano em iogurtes probióticos, a suplementação do aminoácido em bebidas lácteas bubalinas frutadas permitiria a obtenção de um produto funcional, onde seus benefícios estariam relacionados tanto ao consumo do probiótico presente no produto quanto a complementação de triptofano na dieta do consumidor

The aim of this study was to develop a formulation of probiotic buffalo dairy beverage added with strawberry pulp, comparing the effects of using buffalo and cow's milk in the preparation of products and verifying the possibility of tryptophan supplementation in probiotic dairy products. As a first stage of the work, probiotic dairy beverages were made from buffalo and bovine milk, fermented with Streptococcus thermophiles TA040, Lactobacillus bulgaricus LB340 and Lactobacillus acidophilus La5, and formulated with 0, 25 and 50% whey in their formulation. The beverages were evaluated for the fermentation kinetics of the used lactic cultures, the levels of protein, fat and total no fat solids, post-acidification, fermenting cultures viability and their ability to survive gastrointestinal stress in vitro. Buffalo milk use in dairy beverages production promoted benefits regarding the lactic cultures present in the products, exerting a protective effect and influencing the viability preservation of bacteria during the cold storage and simulation of gastrointestinal stress in vitro. Dairy beverages made with 25% whey addition showed results similar to those obtained by the control products, without whey addition, being selected for the second part of the study. In this part, the dairy beverages formulations with 25% whey, were added with a preparation were added with a strawberry pulp preparation and dairy beverages without added fruit, used as a control. Fruity bubaline dairy beverages had lower fat content and better rheological characteristics, with higher viscosity and consistency than control products, without affecting post-acidification, fatty acid profile, as well as viability and resistance to in vitro gastrointestinal condition of fermented cultures. The possibility of supplementing probiotic dairy products with tryptophan was evaluated in partnership with the University of Milan. For this, probiotic yogurts received the addition of tryptophan before or after fermentation, being evaluated in relation to the post-acidification profile, tryptophan amount in the products, viable cell number per plating and flow cytometry during storage at 25°C and 4°C. In addition, the influence of the tryptophan presence on the growth and production of antimicrobial compounds by lactic cultures was also evaluated. The addition of tryptophan after the yogurt fermentation, which were stored under refrigeration (4°C), in addition to not affecting the post-acidification of the products, showed benefits to the viability of L. acidophilus, reduced the damage and increased the number of cells promoting higher amino acid content in yogurts. Tryptophan presence in the culture media also positively influenced the growth of S. thermophiles and L. acidophilus, improving the development of bacteria during fermentation and influencing better antilisteric activity in the part of S. thermophiles. In view of the buffalo milk positive influence observed after the application in dairy beverage preparation, as well as the addition of tryptophan in probiotic yoghurts, amino acid supplementation in fruity buffalo dairy beverages would allow to obtain a functional product, where its benefits would be related both to the consumption of the probiotic present in the product as to the supplementation of tryptophan in the consumer's diet

Desenvolvimento de bebidas lácteas probióticas adicionadas de polpa de morango e suplementadas com L-triptofano elaboradas a partir de leite bubalino e bovino / Development of probiotic dairy beverages with strawberry pulp and supplemented with L-tryptophan from buffalo and bovine milk

O objetivo deste estudo foi desenvolver uma formulação de bebida láctea bubalina probiótica adicionada de polpa de morango, comparando os efeitos do uso do leite de búfala e de vaca na elaboração dos produtos e verificando a possibilidade de suplementação com triptofano nos produtos lácteos probióticos. Como primeira etapa do trabalho, bebidas lácteas probióticas foram elaboradas a partir de leite bubalino e bovino, fermentadas com Streptococcus thermophilus TA040, Lactobacillus bulgaricus LB340 e Lactobacillus acidophilus La5, e formuladas com 0, 25 e 50% de soro em sua formulação. As bebidas foram avaliadas quanto à cinética de fermentação das culturas láticas utilizadas, ao teor de proteína, gordura e sólidos totais não gordurosos, pós-acidificação, viabilidade das culturas fermentadoras e sua capacidade de sobrevivência ao estresse gastrointestinal in vitro. As bebidas lácteas bubalinas apresentaram resultados superiores as bebidas bovinas. O uso do leite de búfala na elaboração das bebidas lácteas promoveu benefícios quanto as culturas láticas presentes nos produtos, exercendo efeito protetivo e influindo na preservação da viabilidade das bactérias ao longo do armazenamento refrigerado e durante a simulação do estresse gastrointestinal in vitro. As bebidas lácteas elaboradas com 25% apresentaram os resultados mais próximos aos obtidos pelos produtos controle, sem adição de soro, sendo selecionadas para a segunda parte do estudo. Nesta etapa, as formulações de bebida láctea com 25% de soro, foram acrescidas de um preparado com polpa de morango e bebidas sem adição da fruta, utilizadas como controle. As bebidas lácteas bubalinas frutadas, apresentaram menor teor de gordura e melhores características reológicas, com maior viscosidade e consistência do que os produtos controle, sem afetar a pós-acidificação, o perfil de ácido graxo, assim como, a viabilidade e a resistência às condições de estresse gastrointestinal in vitro das culturas fermentadoras. A avaliação da possibilidade de suplementar lácteos probióticos com triptofano foi realizada em conjunto com a Universidade de Milão. Para isso, iogurtes probióticos receberam adição de triptofano antes ou após a fermentação, sendo avaliados com relação ao perfil de pós-acidificação, quantidade de triptofano nos produtos, número de células viáveis por plaqueamento e citometria de fluxo ao longo do armazenamento a 25° e 4°C. Complementarmente, a influência da presença do triptofano no crescimento e produção de compostos antimicrobianos pelas culturas láticas, também foi avaliada. A adição de triptofano após a fermentação dos iogurtes, que foram armazenados sob refrigeração (4°C), além de não afetar a pós-acidificação dos produtos, apresentou benefícios quanto a viabilidade L. acidophilus, redução do dano e aumento do número de células vivas, promovendo teor maior do aminoácido nos iogurtes. A presença do triptofano nos meios de cultivo, também influenciou de forma positiva o crescimento de S. thermophilus e L. acidophilus, melhorando o desenvolvimento das bactérias durante a fermentação e influindo em uma maior atividade antilistérica por parte do S. thermophilus. Diante da influência positiva da aplicação do leite de búfala na elaboração das bebidas lácteas, assim como, a adição do triptofano em iogurtes probióticos, a suplementação do aminoácido em bebidas lácteas bubalinas frutadas permitiria a obtenção de um produto funcional, onde seus benefícios estariam relacionados tanto ao consumo do probiótico presente no produto quanto a complementação de triptofano na dieta do consumidor

The aim of this study was to develop a formulation of probiotic buffalo dairy beverage added with strawberry pulp, comparing the effects of using buffalo and cow's milk in the preparation of products and verifying the possibility of tryptophan supplementation in probiotic dairy products. As a first stage of the work, probiotic dairy beverages were made from buffalo and bovine milk, fermented with Streptococcus thermophiles TA040, Lactobacillus bulgaricus LB340 and Lactobacillus acidophilus La5, and formulated with 0, 25 and 50% whey in their formulation. The beverages were evaluated for the fermentation kinetics of the used lactic cultures, the levels of protein, fat and total no fat solids, post-acidification, fermenting cultures viability and their ability to survive gastrointestinal stress in vitro. Buffalo milk use in dairy beverages production promoted benefits regarding the lactic cultures present in the products, exerting a protective effect and influencing the viability preservation of bacteria during the cold storage and simulation of gastrointestinal stress in vitro. Dairy beverages made with 25% whey addition showed results similar to those obtained by the control products, without whey addition, being selected for the second part of the study. In this part, the dairy beverages formulations with 25% whey, were added with a preparation were added with a strawberry pulp preparation and dairy beverages without added fruit, used as a control. Fruity bubaline dairy beverages had lower fat content and better rheological characteristics, with higher viscosity and consistency than control products, without affecting post-acidification, fatty acid profile, as well as viability and resistance to in vitro gastrointestinal condition of fermented cultures. The possibility of supplementing probiotic dairy products with tryptophan was evaluated in partnership with the University of Milan. For this, probiotic yogurts received the addition of tryptophan before or after fermentation, being evaluated in relation to the post-acidification profile, tryptophan amount in the products, viable cell number per plating and flow cytometry during storage at 25°C and 4°C. In addition, the influence of the tryptophan presence on the growth and production of antimicrobial compounds by lactic cultures was also evaluated. The addition of tryptophan after the yogurt fermentation, which were stored under refrigeration (4°C), in addition to not affecting the post-acidification of the products, showed benefits to the viability of L. acidophilus, reduced the damage and increased the number of cells promoting higher amino acid content in yogurts. Tryptophan presence in the culture media also positively influenced the growth of S. thermophiles and L. acidophilus, improving the development of bacteria during fermentation and influencing better antilisteric activity in the part of S. thermophiles. In view of the buffalo milk positive influence observed after the application in dairy beverage preparation, as well as the addition of tryptophan in probiotic yoghurts, amino acid supplementation in fruity buffalo dairy beverages would allow to obtain a functional product, where its benefits would be related both to the consumption of the probiotic present in the product as to the supplementation of tryptophan in the consumer's diet

Correlation between tryptophan daily intake and occupational factors with stress outcome scores among offshore and onshore workers

INTRODUCTION@#Offshore and onshore workers have a higher risk of psychological stress related to their job. Stress reactions vary depending on the type of stressor, the duration or severity of the stressor, their genetics, their coping styles, and their nutrition. Tryptophan is an essential amino acid precursor of serotonin and melatonin, which have an antidepressant effect and roles in stress perception and management. This study assessed the correlation of daily tryptophan intake and occupational factors with stress outcome scores based on the Indonesian Short Version New Brief Job Stress Questionnaire (SV-NBJSQ) among offshore and onshore workers.@*METHODS@#A cross-sectional study was conducted on 14 offshore workers and 20 onshore workers. Interviews and questionnaires were conducted to obtain demographic data, dietary intake, occupational factors, and stress outcome scores. Tryptophan daily intake was measured through a single 24-hour dietary recall and a one-day-weighted food record. Data of average daily intake for two days were analyzed using the NutriSurvey software based on the food composition table from The United States Department of Agriculture National Nutrient Database for calculating tryptophan intake.@*RESULTS@#The median (min-max) tryptophan daily intake of offshore workers was 5.5 (1.9–9.9) mg/kg, and 4.5 (1.4–7.5) mg/kg among onshore workers. There was no difference in tryptophan daily intake between offshore and onshore workers (p = 0.064). There was no significant difference between occupational factors except for the shorter tenure of offshore workers (12.5 vs 3, p < 0.001). There was no significant correlation between tryptophan daily intake and each of the stress outcome scores. There was a significant correlation between occupational factors and stress outcome scores among offshore and onshore workers, specifically between workload and fatigue (r = 0.35, p =0.04), workload and depression (r = 0.4, p = 0.02), interpersonal conflict and anxiety (r = 0.47, p = 0.005), role conflict and anxiety (r = 0.47, p = 0.005), as well as between tenure and physical reaction stress (r = -0.42, p = 0.02).@*CONCLUSION@#Adequate tryptophan daily intake and high stress outcome scores among offshore and onshore oil and gas workers are observed in this study, and no correlation was found between the two. Similar food sources, homogeneous occupational stressors, the selection bias of the “healthy worker effect” or other factors that were not studied may influence the findings. There is a correlation between occupational factors and stress outcome scores, namely workload and fatigue, workload and depression, interpersonal conflict and anxiety, role conflict and anxiety, and tenure and stress physical reactions.

Progress of tryptophan and its metabolites in pathogenesis of allergic asthma / 国际儿科学杂志

Airway epithelial damage, increased Th2 inflammatory response, and impaired immune regulatory T cell function are important mechanisms for the development of asthma.Indoleamine 2, 3-dioxygenase(IDO) is induced by LPS and IFN-γ, which regulates the differentiation of naive T cells into CD4 + CD25 + regulatory T cells(Treg)and induces immune tolerance.It can inhibit eosinophilic airway inflammation.Decreased IDO activity may promote the development of asthma.Tryptophan metabolites act on AhR receptors to promote the production of IL-22 and enhance the integrity of the epithelium and its resistance to infection.The Th17/Treg balance induced by specific immunotherapy could be altered, and Treg cell proliferation was observed.Tryptophan metabolites can reduce airway inflammation and inflammatory cytokine infiltration.D-tryptophan can promote the diversity of intestinal flora, increase the number of Treg in lung and colon, reduce Th2 reaction, and reduce airway hyperresponsiveness.Tryptophan and its metabolites, IDO and D-tryptophan play an important role in the occurrence, development and specific immunotherapy of asthma.

Effects of ring finger and tryptophan-aspartic acid 2 on dendritic spines and synapse formation in cerebral cortex neurons of mice / 南方医科大学学报

OBJECTIVE@#To clarify the functional effects of differential expression of ring finger and tryptophan-aspartic acid 2 (RFWD2) on dendritic development and formation of dendritic spines in cerebral cortex neurons of mice.@*METHODS@#Immunofluorescent staining was used to identify the location and global expression profile of RFWD2 in mouse brain and determine the co-localization of RFWD2 with the synaptic proteins in the cortical neurons. We also examined the effects of RFWD2 over-expression (RFWD2-Myc) and RFWD2 knockdown (RFWD2-shRNA) on dendritic development, dendritic spine formation and synaptic function in cultured cortical neurons.@*RESULTS@#RFWD2 is highly expressed in the cerebral cortex and hippocampus of mice, and its expression level was positively correlated with the development of cerebral cortex neurons and dendrites. RFWD2 expression was detected on the presynaptic membrane and postsynaptic membrane of the neurons, and its expression levels were positively correlated with the length, number of branches and complexity of the dendrites. In cultured cortical neurons, RFWD2 overexpression significantly lowered the expressions of the synaptic proteins synaptophysin (P < 0.01) and postsynapic density protein 95 (P < 0.01), while RFWD2 knockdown significantly increased their expressions (both P < 0.05). Compared with the control and RFWD2-overexpressing cells, the neurons with RFWD2 knockdown showed significantly reduced number of dendritic spines (both P < 0.05).@*CONCLUSION@#RFWD2 can regulate the expression of the synaptic proteins, the development of the dendrites, the formation of the dendritic spines and synaptic function in mouse cerebral cortex neurons through ubiquitination of Pea3 family members and c-Jun, which may serve as potential treatment targets for neurological diseases.

Role of gut microbiota and tryptophan metabolism in nonalcoholic fatty liver disease / 临床肝胆病杂志

Nonalcoholic fatty liver disease (NAFLD) is a manifestation of multi-system dysfunction involving the liver, ranging from simple hepatic steatosis to nonalcoholic steatohepatitis, liver fibrosis, liver cirrhosis, and hepatocellular carcinoma. An increasing number of studies have shown the importance of the changes in gut microbiota dysbiosis and its metabolites in NAFLD. Tryptophan and its derivatives produced by gut microbiota have the effects on improving intestinal barrier function, regulating abnormal glucose and lipid metabolism, and alleviating insulin resistance and inflammatory response. This article reviews gut microbiota, tryptophan and its metabolites, and the effect of their interaction on NAFLD.

Tryptophan and tumor immunity / 药学学报

As an essential amino acid, tryptophan (Trp) has various physiological functions and is of great significance in the metabolic process of tumors. In the human body, tryptophan is mainly transformed through kynurenine metabolic pathway, which not only promotes the inherent malignant properties of tumor cells, but also leads to immune-suppressive tumor microenvironment. Changes in tryptophan metabolism often occur in tumors, accompanied by abnormal gene expression of tryptophan-related enzymes, among which indoleamine 2,3-bioxygenase (IDO)-related gene expression and tryptophan 2,3-dioxygenase (TDO)-related gene changes are the most significant. A large number of clinical trials on IDO inhibitors, TDO inhibitors and combination therapy have been carried out. This paper reviewed the tryptophan metabolic pathway, regulation of IDO (TDO), kynurenine (KYN) and other related genes in tumor cells, and outlined the development of therapeutic schedule targeting tryptophan-related genes. The new progress provides new ideas for the further exploration of tumor treatment options.

Investigation of Neuroprotective Effect of Geniposide on Chronic Alcoholism Rats Based on Metabonomics / 中国实验方剂学杂志

ObjectiveMetabolomics was used to identify biomarkers of chronic alcoholism， and to evaluate the neuroprotective effect of geniposide， providing reference for the diagnosis and treatment of chronic alcoholism. MethodThe rat model of chronic alcoholism was established by intragastric administration of 50% ethanol with 8 mL·kg-1 for 14 days， and then increased to 12 mL·kg-1 for 21 days. Meanwhile， the intervention was performed by continuous gavage of geniposide （15 mg·kg-1） for 35 days. At the end of the experiment， the biochemical indexes and histopathological morphology of liver and brain tissues of rats were detected. Ultra performance liquid chromatography-quadrupole-time-of-flight tandem mass spectrometry （UPLC-Q-TOF-MS） was used for urine metabonomics. The chromatographic conditions was as follows：ACQUITY UPLC™ HSS T3 column （2.1 mm×100 mm， 1.8 μm）， mobile phase of 0.1% formic acid acetonitrile solution （A）-0.1% formic acid aqueous solution （B） for gradient elution （0-2.5 min， 1%-11%A； 2.5-4.5 min， 11%-21%A； 4.5-7.0 min， 21%-40%A； 7.0-8.5 min， 40%-99%A； 8.5-10.5 min， 99%A； 10.5-10.6 min， 99%-1%A； 10.6-13.0 min， 1%A）， the flow rate of 0.4 mL·min-1. The conditions of mass spectrometry were electrospray ionization （ESI）， positive and negative ion modes， scanning range of m/z 50-1 200. Progenesis QI 2.0 and MassLynx 4.1 were used for data analysis， and biomarkers were identified by matching element composition and secondary fragments with Human Metabolome Database （HMDB）. ResultThe pathological results showed that on the 35th day of model replication， compared with the model group， the cortical neurons in the geniposide group showed a significantly improved state of disorder， nuclear pyknosis， hyperchromatism and cell membrane boundary blurred necrosis. The biochemical results showed that geniposide could significantly increase the activities of glutathione peroxidase （GSH-Px） and superoxide dismutase （SOD）， decrease the activity of acetylcholinesterase （AChE）， decrease the levels of β-endorphin （β-EP） and malondialdehyde （MDA）. A total of 48 biomarkers of chronic alcoholism were identified by metabonomics， involving seven metabolic pathways of tryptophan metabolism， phenylalanine metabolism， pentose and glucuronate interconversions， pyrimidine metabolism， ascorbate and aldarate metabolism， steroid hormone biosynthesis and purine metabolism. The main pathway is 5-hydroxytryptamine pathway of tryptophan metabolism. ConclusionBiomarkers related to nerve injury in chronic alcoholism are mainly derived from the 5-hydroxytryptamine metabolic pathway. Geniposide can regulate this pathway so as to improve oxidative stress in the brain and play a neuroprotective role.