Ischemic stroke,which is characterized by hypoxia and ischemia,triggers a cascade of injury responses,including neurotoxicity,inflammation,oxidative stress,disruption of the blood-brain barrier,and neuronal death.In t...Ischemic stroke,which is characterized by hypoxia and ischemia,triggers a cascade of injury responses,including neurotoxicity,inflammation,oxidative stress,disruption of the blood-brain barrier,and neuronal death.In this context,tryptophan metabolites and enzymes,which are synthesized through the kynurenine and 5-hydroxytryptamine pathways,play dual roles.The delicate balance between neurotoxic and neuroprotective substances is a crucial factor influencing the progression of ischemic stroke.Neuroprotective metabolites,such as kynurenic acid,exert their effects through various mechanisms,including competitive blockade of N-methyl-D-aspartate receptors,modulation ofα7 nicotinic acetylcholine receptors,and scavenging of reactive oxygen species.In contrast,neurotoxic substances such as quinolinic acid can hinder the development of vascular glucose transporter proteins,induce neurotoxicity mediated by reactive oxygen species,and disrupt mitochondrial function.Additionally,the enzymes involved in tryptophan metabolism play major roles in these processes.Indoleamine 2,3-dioxygenase in the kynurenine pathway and tryptophan hydroxylase in the 5-hydroxytryptamine pathway influence neuroinflammation and brain homeostasis.Consequently,the metabolites generated through tryptophan metabolism have substantial effects on the development and progression of ischemic stroke.Stroke treatment aims to restore the balance of various metabolite levels;however,precise regulation of tryptophan metabolism within the central nervous system remains a major challenge for the treatment of ischemic stroke.Therefore,this review aimed to elucidate the complex interactions between tryptophan metabolites and enzymes in ischemic stroke and develop targeted therapies that can restore the delicate balance between neurotoxicity and neuroprotection.展开更多
Background:Tertiary lymphoid structures(TLSs)promote antitumor immunity and predict favorable immunotherapy outcomes in breast cancer.The study aimed to investigate how Tryptophan 2,3-dioxygenase(TDO2)-associated tryp...Background:Tertiary lymphoid structures(TLSs)promote antitumor immunity and predict favorable immunotherapy outcomes in breast cancer.The study aimed to investigate how Tryptophan 2,3-dioxygenase(TDO2)-associated tryptophan metabolism influences TLS maturation and B cell class switching in breast cancer.Methods:Bulk transcriptomic data from The Cancer Genome Atlas-Breast Invasive Carcinoma(TCGA-BRCA,n=1055)were analyzed using Gene Set Variation Analysis(GSVA)-based metabolic scoring,immune deconvolution,and TLS quantification.Single-cell RNA sequencing(scRNA-seq,n=26)and spatial transcriptomics(n=1)were applied to map TDO2 expression and TLS spatial organization.Validation was performed by immunohistochemistry(n=38)and multiplex immunofluorescence(n=12).Results:We identified that elevated tryptophan metabolism was predominantly enriched in the Luminal A subtype and delineates an immune-cold phenotype with less immunogenicity,associated with a distinct immune-dominant cellular microenvironment,particularly enriched in T and plasma cells.High expression of the tryptophan-metabolizing enzyme TDO2 was significantly enriched in TLS-low tumors and negatively correlated with TLS maturation signatures.Functional enrichment revealed suppressed B cell class switching and attenuated C-X-C motif chemokine ligand 9(CXCL9)expression in TLS-deficient tumors.Spatial transcriptomics and hotspot analysis demonstrated an inverse spatial correlation between TDO2 expression and TLS core components.Tumors with high tryptophan metabolism showed decreased cluster of differentiation 20(CD20)^(+)and CXCL9^(+)cell infiltration within TLS zones.Tumors with strong TDO2-kynurenine activity displayed impaired TLS organization and attenuated humoral immunity.Conditional spatial co-occurrence modeling confirmed reduced proximity between tryptophan metabolism hotspots and TLS-related immune features.Conclusion:In conclusion,our findings suggest that TDO2-associated tryptophan metabolism is linked to impaired TLS maturation and suppressed B cell class switching in breast cancer.Targeting the TDO2-kynurenine axis may represent a promising strategy to restore TLS formation and enhance immunotherapy responsiveness in breast cancer.展开更多
Objective:Prenatal depression is one of the most common psychological disorders during pregnancy,with an incidence of approximately 19.7%in China,and the incidence is showing a significant upward trend.Prenatal depres...Objective:Prenatal depression is one of the most common psychological disorders during pregnancy,with an incidence of approximately 19.7%in China,and the incidence is showing a significant upward trend.Prenatal depression seriously endangers maternal and infant health,may lead to self-injury and suicide,and has lasting effects on the health of offspring.Studies have shown that gut microbiota imbalance and disruption of the gutbrain axis can affect brain function and behavior and play an important role in the occurrence and development of depression.Significant changes occur in the gut microbiota of pregnant women during pregnancy,which may influence inflammation and metabolism.Gut microbiota play a key role in tryptophan metabolism;however,the mechanisms by which maternal gut microbiota regulate tryptophan metabolism to affect brain function and mood remain unclear.This study aims to clarify the role of plasma tryptophan in the relationship between gut microbiota and prenatal depression in pregnant women based on the gut-brain axis mechanism.Methods:A total of 73 pregnant women were included in the study.The Edinburgh Postnatal Depression Scale(EPDS)was used for assessment.According to the cutoff score(10 points),participants were divided into a prenatal depression group(pregnant women with prenatal depression)and a control group(pregnant women without prenatal depression).Demographic information,fecal samples,and plasma samples were collected.Gut microbiota sequencing was performed using 16S ribosomal RNA(rRNA)sequencing.Amino acid detection in plasma and feces was conducted using ultrahigh performance liquid chromatography-electrospray ionization tandem mass spectrometry(UHPLC-ESIMS/MS).Data were analyzed using SPSS 26.0 and R software,and mediation model analysis was performed using SPSS PROCESS.Results:There were no statistically significant differences inα-diversity orβ-diversity of gut microbiota between the 2 groups(all P>0.05).Compared with the control group,plasma tryptophan levels were significantly higher in the prenatal depression group(t=−2.964,P<0.05).The abundances of Candidatus_Soleaferrea(β=−19.945,OR<0.001,95%CI<0.001 to 0.002,P=0.004)and Enterococcus(β=−9.074,OR<0.001,95%CI<0.001 to 0.183,P=0.016)were negatively correlated with prenatal depression,whereas the abundance of Lachnospiraceae_NC2004_group was positively correlated with prenatal depression(β=5.870,OR=354.354,95%CI 1.248 to 100619.527,P=0.042).Plasma tryptophan levels played a mediating role between Enterococcus abundance and prenatal depression.Conclusion:Depressive symptoms during pregnancy are associated with the composition of gut microbiota during pregnancy.Tryptophan,as a precursor of serotonin,may play a mediating role in this process,providing new insights for improving prenatal depression through interventions targeting gut microbiota or tryptophan metabolism.展开更多
Inflammation is often accompanied by glioblastoma cells(GBMs)and is considered a key factor for GBM growth.This feature is believed to be connected with the tryptophan pathway mainly affected by intestinal microbes si...Inflammation is often accompanied by glioblastoma cells(GBMs)and is considered a key factor for GBM growth.This feature is believed to be connected with the tryptophan pathway mainly affected by intestinal microbes since the concept of gut-brain axis(GBA)has been proposed.Here we present a microchip model co-culturing intestinal cells(Caco2),microbes(E.coli),and GBM cells(U87)to study inflammatory responses of GBM by investigating the tryptophan metabolism.E.coli after encapsulating with alginate hydrogel microparticles(AHMPs)was seeded in the microchip where Caco2 was located,forming the simulated system of intestinal physiology and avoiding excessive reproduction of microbes.Continuous flow was applied to maintain the cell viability,induce the morphogenesis,and simulate the tryptophan transportation in GBA.The morphological alterations of Caco2 and U87 were characterized by fluorescence imaging and the tryptophan metabolism,especially the tryptophan-kynurenine pathway,was analyzed by LC-MS.Above these results of molecular analysis and cell behavior,we can conclude that GBM inflammation is induced by tryptophan accumulation.This microchip-based model generally provides an alternative method for in vitro research of interactions in GBA.展开更多
Background Diets with high inclusion of corn co-products such as corn fermented protein(CFP)may contain excess Leu,which has a negative impact on feed intake and growth performance of pigs due to increased catabolism ...Background Diets with high inclusion of corn co-products such as corn fermented protein(CFP)may contain excess Leu,which has a negative impact on feed intake and growth performance of pigs due to increased catabolism of Val and Ile and reduced availability of Trp in the brain for serotonin synthesis.However,we hypothesized that the negative effect of using CFP in diets for weanling pigs may be overcome if diets are fortified with crystalline sources of Val,Trp,and(or)Ile.Methods Three hundred and twenty weanling pigs were randomly allotted to one of 10 dietary treatments in a com-pletely randomized design,with 4 pigs per pen and 8 replicate pens per treatment.A corn-soybean meal diet and 2 basal diets based on corn and 10%CFP or corn and 20%CFP were formulated.Seven additional diets were formu-lated by fortifying the basal diet with 20%CFP with Ile,Trp,Val,Ile and Val,Ile and Trp,Trp and Val,or Ile,Trp and Val.A two-phase feeding program was used,with d 1 to 14 being phase 1 and d 15 to 28 being phase 2.Fecal scores were recorded every other day.Blood samples were collected on d 14 and 28 from one pig per pen.On d 14,fecal samples were collected from one pig per pen in 3 of the 10 treatments to determine volatile fatty acids,ammonium concen-tration,and microbial protein.These pigs were also euthanized and ileal tissue was collected.Results There were no effects of dietary treatments on any of the parameters evaluated in phase 1.Inclusion of 10%or 20%CFP in diets reduced(P<0.05)final body weight on d 28,and average daily gain(ADG)and average daily feed intake(ADFI)in phase 2 and for the entire experimental period.However,pigs fed the CFP diet supplemented with Val,Ile,and Trp had final body weight,ADFI,ADG and gain to feed ratio in phase 2 and for the entire experiment that was not different from pigs fed the control diet.Fecal scores in phase 2 were reduced(P<0.05)if CFP was used.Conclusions Corn fermented protein may be included by up to 20%in diets for weanling pigs without affecting growth performance,gut health,or hindgut fermentation,if diets are fortified with extra Val,Trp,and Ile.Inclusion of CFP also improved fecal consistency of pigs.展开更多
Background Tryptophan is essential for nutrition,immunity and neural activity,but cannot be synthesized endogenously.Certain natural products influence host health by modulating the gut microbiota to promote the produ...Background Tryptophan is essential for nutrition,immunity and neural activity,but cannot be synthesized endogenously.Certain natural products influence host health by modulating the gut microbiota to promote the production of tryptophan metabolites.Sanguinarine(SAN)enhances broiler immunity,however,its low bioavailability and underlying mechanisms remain unclear.This study aimed to decode the mechanisms by which sanguinarine enhances intestinal immune function in broilers.Methods Liquid chromatography-tandem mass spectrometry(LC-MS/MS)was employed to identify the main metabolites of sanguinarine in the intestine.Subsequently,equal concentrations of sanguinarine and its metabolites were separately added to the diets.The effects of sanguinarine and its metabolites on the intestinal immune function of broiler chickens were evaluated using 16S rRNA gene amplicon sequencing and tryptophan metabolomics approaches.Results We determined that dihydrosanguinarine(DHSA)is the main metabolite of sanguinarine in the intestine.Both compounds increased average daily gain and reduced feed efficiency,thereby improving growth performance.They also enhanced ileal villus height and the villus-to-crypt(V/C)ratio while decreasing crypt depth and upregulating the mRNA expression of tight junction proteins ZO-1,occludin and claudin-1.Furthermore,both compounds promoted the proliferation of intestinal Lactobacillus species,a tryptophan-metabolizing bacterium,stimulated short-chain fatty acid production,and lowered intestinal pH.They regulated tryptophan metabolism by increasing the diversity and content of indole tryptophan metabolites,activating the aryl hydrocarbon receptor(AhR)pathway,and elevating the mRNA levels of CYP1A1,CYP1B1,SLC3A1,IDO2 and TPH1.Inflammatory cytokines IL-1β and IL-6 were inhibited,while anti-inflammatory cytokines IL-10 and IL-22,serum SIgA concentration,and intestinal MUC2 expression were increased.Notably,DHSA exhibited a more pronounced effect on enhancing immune function compared to SAN.Conclusions SAN is converted to DHSA in vivo,which increases its bioavailability.DHSA regulates tryptophan metabolism by activating the AhR pathway and modulating immune-related factors through changes in the gut microbiota.Notably,DHSA significantly increases the abundance of Lactobacillus,a key tryptophan-metabolizing bacterium,thereby enhancing intestinal immune function and improving broiler growth performance.展开更多
Obesity is a major focus of researchers due to its increasing prevalence and relationship with other diseases,such as cancer and cardiovascular diseases.Probiotics are active microorganisms and have been proven to all...Obesity is a major focus of researchers due to its increasing prevalence and relationship with other diseases,such as cancer and cardiovascular diseases.Probiotics are active microorganisms and have been proven to alleviate obesity by modulating the microbiota.In this study,we found that oral administration of Bifidobacterium adolescentis CCFM8630 to obese mice inhibited high-fat diet(HFD)-induced changes in body weight and adipose tissue and alleviated hepatic oxidative stress.Furthermore,B.adolescentis CCFM8630 treatment primarily affected the relative abundances of the phyla Proteobacteria and Actinobacteria,and thereby decreased the production of lipopolysaccharide(LPS)and the occurrence of LPS related diseases.A high fiber intake increased the abundance of Lactobacillus and the concentrations of short chain fatty acids in obese mice,but these changes were reversed by B.adolescentis CCFM8630 treatment.In addition,targeted metabolomic analysis and microbiota relationship analysis revealed that B.adolescentis CCFM8630 treatment modified the microbiota of obese mice by promoting the conversion of tryptophan(Trp)to xanthurenic acid,kynurenic acid,tryptamine,indole-3-acetic acid,and indole-3-carboxaldehyde;facilitated the expression of interleukin-17A and the aryl hydrocarbon receptor to generate interleukin-22 in the colon;and upregulated the expression of tight junction proteins,thereby strengthening intestinal barriers.In summary,our findings suggest that the intake of B.adolescentis CCFM8630 may alleviate obesity by modulating the gut microbiota and related Trp metabolism.展开更多
Obesity is a common noncommunicable disease characterized by persistent low-grade chronic inflammation and is associated with various metabolic disturbances,including insulin resistance and diabetes.The search for eff...Obesity is a common noncommunicable disease characterized by persistent low-grade chronic inflammation and is associated with various metabolic disturbances,including insulin resistance and diabetes.The search for effective obesity treatments has led to growing interest in the role of amino acids in metabolic regulation.Tryptophan(TRP),an essential amino acid,participates in several biological pathways,including the kynurenine,5-hydroxytryptamine(5-HT,also known as serotonin),and indole pathways.Recent evidence underscores the significance of TRP metabolism in obesity,showing that various metabolites and enzymes in its metabolic pathways are altered in individuals with obesity.These changes influence physiological processes,mood regulation,and overall metabolic health.This review provides a comprehensive overview of TRP metabolism.It highlights the potential of targeting TRP metabolism as a therapeutic strategy for managing obesity and its related metabolic and psychological comorbidities.展开更多
In this study,a novel colorimetric detection method for tryptophan is developed using Au@MnO_(2)NPs based on their redox reaction.Tryptophan etches the outer MnO_(2)NPs shell and forms a stable protective layer outsid...In this study,a novel colorimetric detection method for tryptophan is developed using Au@MnO_(2)NPs based on their redox reaction.Tryptophan etches the outer MnO_(2)NPs shell and forms a stable protective layer outside the released AuNPs core in situ,accompanied by a noticeable color change from brown to pink.According to the absorbance ratio of 545 nm and 580 nm(A_(545)/A_(580)),a rapid(within 1 min),accurate,and specific detection method for tryptophan is constructed amidst other common amino acids.Coupling with a smartphone application,integrated Au@MnO_(2)NPs-based portable test strips can be used for the point-of-care testing(POCT)of tryptophan.展开更多
Objectives:Triple-negative breast cancer(TNBC)is the breast cancer subtype with the poorest prognosis.This study aimed to elucidate the molecular pathways through which isoliquiritigenin(ISL),a natural chalcone compou...Objectives:Triple-negative breast cancer(TNBC)is the breast cancer subtype with the poorest prognosis.This study aimed to elucidate the molecular pathways through which isoliquiritigenin(ISL),a natural chalcone compound derived fromlicorice and other plant roots,targets interferon regulatory factor 5(IRF5)in TNBC.Methods:TNBC cell lines were cultured and subjected to IRF5 knockdown using short hairpin RNA.Cell proliferation was assessed by cell counting kit-8(CCK-8)assay and colony formation assays.Western blotting and quantitative reverse transcription polymerase chain reaction(RT-PCR)were employed to measure expression levels of IRF5,solute carrier family 7 member 5(SLC7A5),and indoleamine 2,3-dioxygenase 1(IDO1).Intracellular tryptophan and its metabolites were quantified using commercially available assay kits and high-performance liquid chromatography(HPLC).TNBC cells were treated with various concentrations of ISL to evaluate its effects on proliferation and tryptophanmetabolism.Results:IRF5 was highly expressed in TNBC cell lines.Silencing IRF5 significantly inhibited cellular proliferation and growth.Knockdown of IRF5 reduced the expression of SLC7A5 and IDO1,leading to decreased intracellular levels of tryptophan and its metabolites.ISL markedly suppressed TNBC cell proliferation and disrupted tryptophan metabolism in tumor cells.Conclusion:ISL may inhibit TNBC progression by downregulating IRF5 and interfering with SLC7A5/IDO1-mediated tryptophan metabolic reprogramming,suggesting a potential therapeutic mechanism for TNBC treatment.展开更多
The gene encoded for tryptophan decarboxylase (TDC), which is the key enzyme in terpenoil indole alkaloids pathway, was targeted to different subcellular compartments and stably expressed in transgenic tobacco (Nicoti...The gene encoded for tryptophan decarboxylase (TDC), which is the key enzyme in terpenoil indole alkaloids pathway, was targeted to different subcellular compartments and stably expressed in transgenic tobacco (Nicotiana tabacum L.) plants at the levels detected by Western blot and tryptamine accumulation analysis. It was shown that the TDC was located in subcellular compartments, the chloroplasts and cytosol. The recombinant TDC targeted to chloroplasts and cytosol in tobacco plants was effectively expressed as soluble protein by Western blot analysis and enzymatic assay. The level of tryptamine accumulation in chloroplast was higher than that in cytosol and very low in vacuole and endoplasmic reticulum (ER) to be hardly detected by Western blot analysis. It was indicated that the highest amount of tryptamine was in chloroplasts, lower in endoplasmic reticula and the lowest in vacuoles as compared to those in wild type plants. The TDC targeted to different subcellular compartments of tobacco plants and its expression level were studied by different nucleotide sequences coding signal peptides at 5'-end of tdc gene in order to know the effects of the TDC in compartmentation on its functionality.展开更多
Drought stress in plants is accompanied by several metabolic changes. One of them is the appearance of <em>N</em>-malonyltryptophan (MT) during leaf wilting of many species, but there is a significant numb...Drought stress in plants is accompanied by several metabolic changes. One of them is the appearance of <em>N</em>-malonyltryptophan (MT) during leaf wilting of many species, but there is a significant number of plant species in which the appearance of MT did not occur. Plants of some species were able to synthesize also <em>N</em>-acetyltryptophan (AT). Excised tomato leaves incubated with D-amino acids (including D-Trp) transform them into malonyl- and acetyl-derivatives even without water deficit. However, MT which appeared during water deficit has been shown to contain L-Trp. Amino acid—1-amino-cyclopropane-1-carboxylic acid (ACC) is also malonylated during water deficit, but other L-amino acids were not malonylated. <em>N</em>-malonyl transferases specific for Trp and ACC have been found in several plants. The existence of <em>N</em>-malonyltransferase specific to L-Trp and appeared during water deficit in plants forming MT is supposed, but clear experimental proof has not been obtained yet. Plants can transform MT applied exogenously into Trp and further to indole-3-acetic acid (IAA). But no evidence has been appeared up to now that endogenous MT may be a source of IAA. It is unknown till now why it is necessary for plants of many species to malonylate only Trp during water deficit. How MT metabolized in animals and if it affects them is also unknown. The necessity to use molecular-genetic approaches for the elucidation of the physiological significance of MT formation during water deficit is underlined.展开更多
AIM: To evaluate how Helicobacter pylori(H. pylori) is able to evade the immune response and whether it enhances systemic immune tolerance against colorectal cancer.METHODS: This prospective randomized study involved ...AIM: To evaluate how Helicobacter pylori(H. pylori) is able to evade the immune response and whether it enhances systemic immune tolerance against colorectal cancer.METHODS: This prospective randomized study involved 97 consecutive colorectal cancer patients and 108 cancer-free patients with extra-digestive diseases. Colorectal cancer and cancer-free patients were assigned into subgroups according to H. pylori Ig G seropositivity. Exposure to H. pylori was determined by Ig G seropositivity which was detected by enzyme linked immunoassay(ELISA). Serum neopterin levels were measured by ELISA. Serum tryptophan, kynurenine, and urinary biopterin concentrations were measured by high performance liquid chromatography. Serum nitrite levels were detected spectrophotometrically. Serum indoleamine 2,3-dioxygenase activity was estimated by the kynurenine to tryptophan ratio and by assessing the correlation between serum neopterin concentrations and the kynurenine to tryptophan ratio. The frequencies of increased serum kynurenine to tryptophan ratio of H. pylori seronegative and seropositive colorectal cancer subgroups were estimated by comparing them with the average kynurenine to tryptophan ratio of H. pylori seronegative tumor-free patients.RESULTS: Compared with respective controls, in both H. pylori seronegative and seropositive colorectal cancer patients, while serum tryptophan levels were decreased(controls vs patients; seronegative: 20.37 ± 0.89 μmol/L vs 15.71 ± 1.16 μmol/L, P < 0.05; seropositive: 20.71 ± 0.81 μmol/L vs 14.97 ± 0.79 μmol/L, P < 0.01) the kynurenine to tryptophan ratio was significantly increased(controls vs patients; seronegative: 52.85± 11.85 μmol/mmol vs 78.91 ± 8.68 μmol/mmol, P < 0.01, seropositive: 47.31 ± 5.93 μmol/mmol vs 109.65 ± 11.50 μmol/mmol, P < 0.01). Neopterin concentrations in cancer patients were significantly elevated compared with controls(P < 0.05). There was a significant correlation between serum neopterin levels and kynurenine/tryptophan in control and colorectal cancer patients groups(r s = 0.494, P = 0.0001 and r s= 0.293, P = 0.004, respectively). Serum nitrite levels of H. pylori seropositive cancer cases were significantly decreased compared with seropositive controls(controls vs patients; 26.04 ± 2.39 μmol/L vs 20.41 ± 1.48 μmol/L, P < 0.05) The decrease in the nitrite levels of H. pylori seropositive cancer patients may be attributed to excessive formation of peroxynitrite and other reactive nitrogen species.CONCLUSION: A significantly high kynurenine/tryptophan suggested that H. pylori may support the immune tolerance leading to cancer development, even without an apparent upper gastrointestinal tract disease.展开更多
Oxidative stress can induce abnormal tryptophan metabolism. The present study was mainly conducted to determine the effect of dietary tryptophan levels on oxidative stress in the liver of weaned pigs challenged by diq...Oxidative stress can induce abnormal tryptophan metabolism. The present study was mainly conducted to determine the effect of dietary tryptophan levels on oxidative stress in the liver of weaned pigs challenged by diquat. A total of 36 PIC piglets weaned at 21 days of age were randomly allotted to 1 of 3 diets containing dietary tryptophan levels of 0.18, 0.30, and 0A5% for 14 d. On day 8, the piglets were injected intraperitoneally with sterile 0.9% NaCI solution or diquat （10 mg/kg body weight）. During the first 7 d of trial, increasing dietary tryptophan levels enhanced average daily gain （P = 0.09） and average daily feed intake （P = 0.08）, and decreased the feed efficiency （P 〈 0.05） of piglets. The growth performance was decreased by diquat injection （P 〈 0.05）. Diquat injection also decreased the activities of the superoxide dismutase （SOD） and glutathione peroxidase （GPx） in the plasma and liver （P 〈 0.05）, increased plasma malondialdehyde （MDA） （P 〈 0.05） and urea nitrogen （P 〈 0.05） concentrations, and enhanced MDA concentration （P = 0.09） and tryptophan 2,3-dioxygenase （TDO） activity （P = 0.07） in liver of piglets. Increasing dietary tryptophan levels could attenuate the effects of diquat injection on the MDA （P = 0.06） concentration and the activities of SOD （P = 0.09） and GPx （P = 0.05） of the liver, and plasma urea nitrogen （P = 0.06） concentration in the piglet. There was a synergistic role for increasing TDO activity in the liver between dietary tryptophan levels and diquat injection （P 〈 0.05）. These results suggest that increasing dietary tryptophan levels could attenuate the oxidative stress of the liver in weaned piglets intraperitoneally injected with diquat via enhancing the antioxidant capacity.展开更多
Background： Highly automated cage-rearing systems are becoming increasingly popular in China. However, a high stocking density can cause oxidative stress and decrease broiler performance. The tryptophan （TRP） deriv...Background： Highly automated cage-rearing systems are becoming increasingly popular in China. However, a high stocking density can cause oxidative stress and decrease broiler performance. The tryptophan （TRP） derivative 5-hydroxytryptophan （5-HT） has been shown to preserve membrane fluidity in birds suffering from oxidative stress Therefore, this experiment was conducted to determine the effects of dietan/TRP supplementation on performance, breast meat quality and oxidative stress in broilers reared in cages with a high or low stocking density. Methods： Female Arbor Acres broilers （25-d-old, n = 144） were randomly allocated to 1 of 4 treatments. The birds were fed a diet based on corn, soybean meal, cottonseed meal and corn gluten meal containing either 0.18 or 0.27% TRP and were housed with stocking densities of 11 or 15.4 birds/m2 in a 2 x 2 factorial experiment. Broiler performance was evaluated from d 25 to 42. Eight birds from each treatment were slaughtered on d 42 and plasma and breast muscle samples were collected to measure biochemical indices. Results： A higher stocking density tended to be associated with reduced weight gain （P 〈 0.10）, and significantly increased plasma glutamic-pyruvic transaminase （GPT） activity （P 〈 0.001）. Increased dietary TRP significantly reduced the activities of lactic dehydrogenase and GPT while increasing total cholesterol in the plasma （P 〈 0.01）, reducing drip loss of breast muscle （P 〈 0.10） and improving feed efficiency （P 〈 0.10）. Conclusions： An increase in dietary TRP, ].S-fold higher than the standard supplementation level, can alleviate oxidative stress as well as improve welfare and feed efficiency in broilers reared in cages with a high stocking density.展开更多
Background Pectin is a heteropolysaccharide that acts as an intestinal immunomodulator,promoting intestinal development and regulating intestinal flora in the gut.However,the relevant mechanisms remain obscure.In this...Background Pectin is a heteropolysaccharide that acts as an intestinal immunomodulator,promoting intestinal development and regulating intestinal flora in the gut.However,the relevant mechanisms remain obscure.In this study,pigs were fed a corn-soybean meal-based diet supplemented with either 5%microcrystalline cellulose(MCC)or 5%pectin for 3 weeks,to investigate the metabolites and anti-inflammatory properties of the jejunum.Result The results showed that dietary pectin supplementation improved intestinal integrity(Claudin-1,Occludin)and inflammatory response[interleukin(IL)-10],and the expression of proinflammatory cytokines(IL-1β,IL-6,IL-8,TNF-α)was down-regulated in the jejunum.Moreover,pectin supplementation altered the jejunal microbiome and tryptophan-related metabolites in piglets.Pectin specifically increased the abundance of Lactococcus,Enterococcus,and the microbiota-derived metabolites(skatole(ST),3-indoleacetic acid(IAA),3-indolepropionic acid(IPA),5-hydroxyindole-3-acetic acid(HIAA),and tryptamine(Tpm)),which activated the aryl hydrocarbon receptor(AhR)pathway.AhR activation modulates IL-22 and its downstream pathways.Correlation analysis revealed the potential relationship between metabolites and intestinal morphology,intestinal gene expression,and cytokine levels.Conclusion In conclusion,these results indicated that pectin inhibits the inflammatory response by enhancing the AhR-IL22-signal transducer and activator of transcription 3 signaling pathway,which is activated through tryptophan metabolites.展开更多
Unbalanced brain serotonin(5-HT) levels have implications in various behavioral abnormalities and neuropsychiatric disorders. The biosynthesis of neuronal 5-HT is regulated by the rate-limiting enzyme, tryptophan hydr...Unbalanced brain serotonin(5-HT) levels have implications in various behavioral abnormalities and neuropsychiatric disorders. The biosynthesis of neuronal 5-HT is regulated by the rate-limiting enzyme, tryptophan hydroxylase-2(TPH2). In the present study, the clustered regularly interspaced short palindromic repeat(CRISPR)/CRISPR-associated(Cas) system was used to target the Tph2 gene in Bama mini pig fetal fibroblasts. It was found that CRISPR/Cas9 targeting efficiency could be as high as 61.5%, and the biallelic mutation efficiency reached at38.5%. The biallelic modified colonies were used as donors for somatic cell nuclear transfer(SCNT) and 10 Tph2 targeted piglets were successfully generated. These Tph2 KO piglets were viable and appeared normal at the birth.However, their central 5-HT levels were dramatically reduced, and their survival and growth rates were impaired before weaning. These Tph2 KO pigs are valuable large-animal models for studies of 5-HT deficiency induced behavior abnomality.展开更多
Objective To investigate changes of 5-hydroxytryptamine （5-HT） and its synthesis rate-limiting enzyme tryp-tophan hydroxylase （TPH） in the ventral horn of spinal cord after exercise-induced fatigue, and to further...Objective To investigate changes of 5-hydroxytryptamine （5-HT） and its synthesis rate-limiting enzyme tryp-tophan hydroxylase （TPH） in the ventral horn of spinal cord after exercise-induced fatigue, and to further discuss the mecha- nism of exercise-induced central fatigue at spinal level. Methods Sixteen healthy adult Wistar rats were randomly divided into 2 groups： exercise-induced fatigue group and control group. Immunohistochemical staining for 5-HT and TPH in the ventral horn were performed and analysized quantitatively. The mean optic densities of 5-HT and TPH positive fibers or terminals were measured by computerized image analyzer. Results Both 5-HT and TPH positive fibers/terminals decreased in the exercise-induced fatigue group. The immunohistochemical staining was weaker and the mean optic densities decreased obviously in the fatigue group compared with those in the control group （P 〈 0.05）. Conclusion 5-HT and TPH in the ventral horn of spinal cord might be involved in exercise-induced fatigue.展开更多
A feed trial was conducted with a total of 1 134 Beijing ducklings to study the optimum level of dietary lysine （Lys） （0.95, 1.10, 1.25%）, methionine （Met） （0.26, 0.46, 0.66%） and tryptophan （Trp） （0.20, 0....A feed trial was conducted with a total of 1 134 Beijing ducklings to study the optimum level of dietary lysine （Lys） （0.95, 1.10, 1.25%）, methionine （Met） （0.26, 0.46, 0.66%） and tryptophan （Trp） （0.20, 0.30, 0.40%） for those ducklings during a phase of 0-2 weeks. Ducklings were randomly allotted to 27 groups according to a 3 × 3× 3 factorial arrangement and fed a basal corn-soybean-peanut meal diet containing 20.26% CP, 12.45 MJ kg^-1 ME. The results from this study indicate that Lys affected body weight （P〈0.01）, feed intake （0-14 d） （P〈0.01）, but had no effect on feed/gain （0-14 d） （P〉0.05）, uric acid concentration （P 〉 0.05）. Methionine influenced body weight （P 〈 0.01）, feed/gain （P 〈 0.05）, and feed intake （P 〈 0.01）. Tryphtophan had no effect on indices measured. The requirement of the Lys and Met for Beijing ducklings of 0-2 weeks of age were 1.10 and 0.46%. The requirement of Trp for Beijing ducklings of 0-2 weeks of age was not more than 0.20%.展开更多
Inflammatory bowel diseases(IBD), which comprise Crohn's disease and ulcerative colitis, are chronic intestinal disorders with an increased prevalence and incidence over the last decade in many different regions o...Inflammatory bowel diseases(IBD), which comprise Crohn's disease and ulcerative colitis, are chronic intestinal disorders with an increased prevalence and incidence over the last decade in many different regions over the world. The etiology of IBD is still not well defined, but evidence suggest that it results from per-turbation of the homeostasis between the intestinal microbiota and the mucosal immune system, with the involvement of both genetic and environmental factors. Genome wide association studies, which involve large-scale genome-wide screening of potential polymorphism, have identified several mutations associated with IBD. Among them, Card9, a gene encoding an adapter molecule involved in innate immune response to fungi(via type C-lectin sensing) through the activation of IL-22 signaling pathway, has been identified as one IBD susceptible genes. Dietary compounds, which represent a source of energy and metabolites for gut bacteria, are also appreciated to be important actors in the etiology of IBD, for example by altering gut microbiota composition and by regulating the generation of short chain fatty acids. A noteworthy study published in the June 2016 issue of Nature Medicine by Lamas and colleagues investigates the interaction between Card9 and the gut microbiota in the generation of the microbiota-derived tryptophan metabolite. This study highlights the role of tryptophan in dampening intestinal inflammation in susceptible hosts.展开更多
基金supported by Shanghai Shenkang Center Demonstration Research Ward Construction,No.SHDC2022CRW010(to MF)Shanghai Shenkang Center Medical Enterprise Integration and Innovation Collaborative Special Project,No.SHDC2022CRT018(to MF)+4 种基金Shanghai Health System Key Supported Discipline-Rehabilitation Medicine,No.2023ZDFC0301(to JT)Science and Technology Development Project of Shanghai University of Traditional Chinese Medicine,No.23KFL009(to JT)Shanghai Postdoctoral Excellence Program,No.2022515(to CY)Yangfan Special Project of Shanghai Science and Technology Innovation Action Plan,No.23YF1447600(to CY)China Postdoctoral Science Foundation,No.2023M732338(to CY).
文摘Ischemic stroke,which is characterized by hypoxia and ischemia,triggers a cascade of injury responses,including neurotoxicity,inflammation,oxidative stress,disruption of the blood-brain barrier,and neuronal death.In this context,tryptophan metabolites and enzymes,which are synthesized through the kynurenine and 5-hydroxytryptamine pathways,play dual roles.The delicate balance between neurotoxic and neuroprotective substances is a crucial factor influencing the progression of ischemic stroke.Neuroprotective metabolites,such as kynurenic acid,exert their effects through various mechanisms,including competitive blockade of N-methyl-D-aspartate receptors,modulation ofα7 nicotinic acetylcholine receptors,and scavenging of reactive oxygen species.In contrast,neurotoxic substances such as quinolinic acid can hinder the development of vascular glucose transporter proteins,induce neurotoxicity mediated by reactive oxygen species,and disrupt mitochondrial function.Additionally,the enzymes involved in tryptophan metabolism play major roles in these processes.Indoleamine 2,3-dioxygenase in the kynurenine pathway and tryptophan hydroxylase in the 5-hydroxytryptamine pathway influence neuroinflammation and brain homeostasis.Consequently,the metabolites generated through tryptophan metabolism have substantial effects on the development and progression of ischemic stroke.Stroke treatment aims to restore the balance of various metabolite levels;however,precise regulation of tryptophan metabolism within the central nervous system remains a major challenge for the treatment of ischemic stroke.Therefore,this review aimed to elucidate the complex interactions between tryptophan metabolites and enzymes in ischemic stroke and develop targeted therapies that can restore the delicate balance between neurotoxicity and neuroprotection.
基金supported by grants from the Beijing Xisike Clinical Oncology Research Foundation(No.Y-Young2024-0138)China Postdoctoral Science Foundation(No.2024M750538)Qingdao Chengyang People’s Hospital Fund Project(No.202510300).
文摘Background:Tertiary lymphoid structures(TLSs)promote antitumor immunity and predict favorable immunotherapy outcomes in breast cancer.The study aimed to investigate how Tryptophan 2,3-dioxygenase(TDO2)-associated tryptophan metabolism influences TLS maturation and B cell class switching in breast cancer.Methods:Bulk transcriptomic data from The Cancer Genome Atlas-Breast Invasive Carcinoma(TCGA-BRCA,n=1055)were analyzed using Gene Set Variation Analysis(GSVA)-based metabolic scoring,immune deconvolution,and TLS quantification.Single-cell RNA sequencing(scRNA-seq,n=26)and spatial transcriptomics(n=1)were applied to map TDO2 expression and TLS spatial organization.Validation was performed by immunohistochemistry(n=38)and multiplex immunofluorescence(n=12).Results:We identified that elevated tryptophan metabolism was predominantly enriched in the Luminal A subtype and delineates an immune-cold phenotype with less immunogenicity,associated with a distinct immune-dominant cellular microenvironment,particularly enriched in T and plasma cells.High expression of the tryptophan-metabolizing enzyme TDO2 was significantly enriched in TLS-low tumors and negatively correlated with TLS maturation signatures.Functional enrichment revealed suppressed B cell class switching and attenuated C-X-C motif chemokine ligand 9(CXCL9)expression in TLS-deficient tumors.Spatial transcriptomics and hotspot analysis demonstrated an inverse spatial correlation between TDO2 expression and TLS core components.Tumors with high tryptophan metabolism showed decreased cluster of differentiation 20(CD20)^(+)and CXCL9^(+)cell infiltration within TLS zones.Tumors with strong TDO2-kynurenine activity displayed impaired TLS organization and attenuated humoral immunity.Conditional spatial co-occurrence modeling confirmed reduced proximity between tryptophan metabolism hotspots and TLS-related immune features.Conclusion:In conclusion,our findings suggest that TDO2-associated tryptophan metabolism is linked to impaired TLS maturation and suppressed B cell class switching in breast cancer.Targeting the TDO2-kynurenine axis may represent a promising strategy to restore TLS formation and enhance immunotherapy responsiveness in breast cancer.
基金supported by the National Natural Science Foundation of China(81903334 and 82473647).
文摘Objective:Prenatal depression is one of the most common psychological disorders during pregnancy,with an incidence of approximately 19.7%in China,and the incidence is showing a significant upward trend.Prenatal depression seriously endangers maternal and infant health,may lead to self-injury and suicide,and has lasting effects on the health of offspring.Studies have shown that gut microbiota imbalance and disruption of the gutbrain axis can affect brain function and behavior and play an important role in the occurrence and development of depression.Significant changes occur in the gut microbiota of pregnant women during pregnancy,which may influence inflammation and metabolism.Gut microbiota play a key role in tryptophan metabolism;however,the mechanisms by which maternal gut microbiota regulate tryptophan metabolism to affect brain function and mood remain unclear.This study aims to clarify the role of plasma tryptophan in the relationship between gut microbiota and prenatal depression in pregnant women based on the gut-brain axis mechanism.Methods:A total of 73 pregnant women were included in the study.The Edinburgh Postnatal Depression Scale(EPDS)was used for assessment.According to the cutoff score(10 points),participants were divided into a prenatal depression group(pregnant women with prenatal depression)and a control group(pregnant women without prenatal depression).Demographic information,fecal samples,and plasma samples were collected.Gut microbiota sequencing was performed using 16S ribosomal RNA(rRNA)sequencing.Amino acid detection in plasma and feces was conducted using ultrahigh performance liquid chromatography-electrospray ionization tandem mass spectrometry(UHPLC-ESIMS/MS).Data were analyzed using SPSS 26.0 and R software,and mediation model analysis was performed using SPSS PROCESS.Results:There were no statistically significant differences inα-diversity orβ-diversity of gut microbiota between the 2 groups(all P>0.05).Compared with the control group,plasma tryptophan levels were significantly higher in the prenatal depression group(t=−2.964,P<0.05).The abundances of Candidatus_Soleaferrea(β=−19.945,OR<0.001,95%CI<0.001 to 0.002,P=0.004)and Enterococcus(β=−9.074,OR<0.001,95%CI<0.001 to 0.183,P=0.016)were negatively correlated with prenatal depression,whereas the abundance of Lachnospiraceae_NC2004_group was positively correlated with prenatal depression(β=5.870,OR=354.354,95%CI 1.248 to 100619.527,P=0.042).Plasma tryptophan levels played a mediating role between Enterococcus abundance and prenatal depression.Conclusion:Depressive symptoms during pregnancy are associated with the composition of gut microbiota during pregnancy.Tryptophan,as a precursor of serotonin,may play a mediating role in this process,providing new insights for improving prenatal depression through interventions targeting gut microbiota or tryptophan metabolism.
基金supported by the National Key R&D Program of China(No.2021YFF0600700)the National Natural Science Foundation of China(No.22034005)+1 种基金Research Projects of Putian University(No.2024172)the Startup Fund for Advanced Talents of Putian University(No.2024046)。
文摘Inflammation is often accompanied by glioblastoma cells(GBMs)and is considered a key factor for GBM growth.This feature is believed to be connected with the tryptophan pathway mainly affected by intestinal microbes since the concept of gut-brain axis(GBA)has been proposed.Here we present a microchip model co-culturing intestinal cells(Caco2),microbes(E.coli),and GBM cells(U87)to study inflammatory responses of GBM by investigating the tryptophan metabolism.E.coli after encapsulating with alginate hydrogel microparticles(AHMPs)was seeded in the microchip where Caco2 was located,forming the simulated system of intestinal physiology and avoiding excessive reproduction of microbes.Continuous flow was applied to maintain the cell viability,induce the morphogenesis,and simulate the tryptophan transportation in GBA.The morphological alterations of Caco2 and U87 were characterized by fluorescence imaging and the tryptophan metabolism,especially the tryptophan-kynurenine pathway,was analyzed by LC-MS.Above these results of molecular analysis and cell behavior,we can conclude that GBM inflammation is induced by tryptophan accumulation.This microchip-based model generally provides an alternative method for in vitro research of interactions in GBA.
基金Financial support for this research from Minnesota Corn Growers Association(Burnsville,MN,USA)Green Plains Energy(Omaha,NE,USA)is greatly appreciated.
文摘Background Diets with high inclusion of corn co-products such as corn fermented protein(CFP)may contain excess Leu,which has a negative impact on feed intake and growth performance of pigs due to increased catabolism of Val and Ile and reduced availability of Trp in the brain for serotonin synthesis.However,we hypothesized that the negative effect of using CFP in diets for weanling pigs may be overcome if diets are fortified with crystalline sources of Val,Trp,and(or)Ile.Methods Three hundred and twenty weanling pigs were randomly allotted to one of 10 dietary treatments in a com-pletely randomized design,with 4 pigs per pen and 8 replicate pens per treatment.A corn-soybean meal diet and 2 basal diets based on corn and 10%CFP or corn and 20%CFP were formulated.Seven additional diets were formu-lated by fortifying the basal diet with 20%CFP with Ile,Trp,Val,Ile and Val,Ile and Trp,Trp and Val,or Ile,Trp and Val.A two-phase feeding program was used,with d 1 to 14 being phase 1 and d 15 to 28 being phase 2.Fecal scores were recorded every other day.Blood samples were collected on d 14 and 28 from one pig per pen.On d 14,fecal samples were collected from one pig per pen in 3 of the 10 treatments to determine volatile fatty acids,ammonium concen-tration,and microbial protein.These pigs were also euthanized and ileal tissue was collected.Results There were no effects of dietary treatments on any of the parameters evaluated in phase 1.Inclusion of 10%or 20%CFP in diets reduced(P<0.05)final body weight on d 28,and average daily gain(ADG)and average daily feed intake(ADFI)in phase 2 and for the entire experimental period.However,pigs fed the CFP diet supplemented with Val,Ile,and Trp had final body weight,ADFI,ADG and gain to feed ratio in phase 2 and for the entire experiment that was not different from pigs fed the control diet.Fecal scores in phase 2 were reduced(P<0.05)if CFP was used.Conclusions Corn fermented protein may be included by up to 20%in diets for weanling pigs without affecting growth performance,gut health,or hindgut fermentation,if diets are fortified with extra Val,Trp,and Ile.Inclusion of CFP also improved fecal consistency of pigs.
基金funded by National Key R&D Program of China(2023YFD1301200)the science and technology innovation Program of Hunan Province(2021RC3091).
文摘Background Tryptophan is essential for nutrition,immunity and neural activity,but cannot be synthesized endogenously.Certain natural products influence host health by modulating the gut microbiota to promote the production of tryptophan metabolites.Sanguinarine(SAN)enhances broiler immunity,however,its low bioavailability and underlying mechanisms remain unclear.This study aimed to decode the mechanisms by which sanguinarine enhances intestinal immune function in broilers.Methods Liquid chromatography-tandem mass spectrometry(LC-MS/MS)was employed to identify the main metabolites of sanguinarine in the intestine.Subsequently,equal concentrations of sanguinarine and its metabolites were separately added to the diets.The effects of sanguinarine and its metabolites on the intestinal immune function of broiler chickens were evaluated using 16S rRNA gene amplicon sequencing and tryptophan metabolomics approaches.Results We determined that dihydrosanguinarine(DHSA)is the main metabolite of sanguinarine in the intestine.Both compounds increased average daily gain and reduced feed efficiency,thereby improving growth performance.They also enhanced ileal villus height and the villus-to-crypt(V/C)ratio while decreasing crypt depth and upregulating the mRNA expression of tight junction proteins ZO-1,occludin and claudin-1.Furthermore,both compounds promoted the proliferation of intestinal Lactobacillus species,a tryptophan-metabolizing bacterium,stimulated short-chain fatty acid production,and lowered intestinal pH.They regulated tryptophan metabolism by increasing the diversity and content of indole tryptophan metabolites,activating the aryl hydrocarbon receptor(AhR)pathway,and elevating the mRNA levels of CYP1A1,CYP1B1,SLC3A1,IDO2 and TPH1.Inflammatory cytokines IL-1β and IL-6 were inhibited,while anti-inflammatory cytokines IL-10 and IL-22,serum SIgA concentration,and intestinal MUC2 expression were increased.Notably,DHSA exhibited a more pronounced effect on enhancing immune function compared to SAN.Conclusions SAN is converted to DHSA in vivo,which increases its bioavailability.DHSA regulates tryptophan metabolism by activating the AhR pathway and modulating immune-related factors through changes in the gut microbiota.Notably,DHSA significantly increases the abundance of Lactobacillus,a key tryptophan-metabolizing bacterium,thereby enhancing intestinal immune function and improving broiler growth performance.
基金supported by the National Natural Science Foundation of China(32272332,32021005,31820103010)the Fundamental Research Funds for the Central Universities(JUSRP622020,JUSRP22006,JUSRP51501)the Program of Collaborative Innovation Centre of Food Safety and Quality Control in Jiangsu Province.
文摘Obesity is a major focus of researchers due to its increasing prevalence and relationship with other diseases,such as cancer and cardiovascular diseases.Probiotics are active microorganisms and have been proven to alleviate obesity by modulating the microbiota.In this study,we found that oral administration of Bifidobacterium adolescentis CCFM8630 to obese mice inhibited high-fat diet(HFD)-induced changes in body weight and adipose tissue and alleviated hepatic oxidative stress.Furthermore,B.adolescentis CCFM8630 treatment primarily affected the relative abundances of the phyla Proteobacteria and Actinobacteria,and thereby decreased the production of lipopolysaccharide(LPS)and the occurrence of LPS related diseases.A high fiber intake increased the abundance of Lactobacillus and the concentrations of short chain fatty acids in obese mice,but these changes were reversed by B.adolescentis CCFM8630 treatment.In addition,targeted metabolomic analysis and microbiota relationship analysis revealed that B.adolescentis CCFM8630 treatment modified the microbiota of obese mice by promoting the conversion of tryptophan(Trp)to xanthurenic acid,kynurenic acid,tryptamine,indole-3-acetic acid,and indole-3-carboxaldehyde;facilitated the expression of interleukin-17A and the aryl hydrocarbon receptor to generate interleukin-22 in the colon;and upregulated the expression of tight junction proteins,thereby strengthening intestinal barriers.In summary,our findings suggest that the intake of B.adolescentis CCFM8630 may alleviate obesity by modulating the gut microbiota and related Trp metabolism.
文摘Obesity is a common noncommunicable disease characterized by persistent low-grade chronic inflammation and is associated with various metabolic disturbances,including insulin resistance and diabetes.The search for effective obesity treatments has led to growing interest in the role of amino acids in metabolic regulation.Tryptophan(TRP),an essential amino acid,participates in several biological pathways,including the kynurenine,5-hydroxytryptamine(5-HT,also known as serotonin),and indole pathways.Recent evidence underscores the significance of TRP metabolism in obesity,showing that various metabolites and enzymes in its metabolic pathways are altered in individuals with obesity.These changes influence physiological processes,mood regulation,and overall metabolic health.This review provides a comprehensive overview of TRP metabolism.It highlights the potential of targeting TRP metabolism as a therapeutic strategy for managing obesity and its related metabolic and psychological comorbidities.
基金College student innovation training program of Guangzhou University,202311078018the National Key Research and Development Program of China,2022YFE0201800+2 种基金Fundamental Research Funds for the Central Universities,24xkjc025Tertiary Education Scientific research project of Guangzhou Municipal Education Bureau,2024312227Guangzhou University Instrument and Equipment Open Sharing Fund,Year 2024。
文摘In this study,a novel colorimetric detection method for tryptophan is developed using Au@MnO_(2)NPs based on their redox reaction.Tryptophan etches the outer MnO_(2)NPs shell and forms a stable protective layer outside the released AuNPs core in situ,accompanied by a noticeable color change from brown to pink.According to the absorbance ratio of 545 nm and 580 nm(A_(545)/A_(580)),a rapid(within 1 min),accurate,and specific detection method for tryptophan is constructed amidst other common amino acids.Coupling with a smartphone application,integrated Au@MnO_(2)NPs-based portable test strips can be used for the point-of-care testing(POCT)of tryptophan.
基金supported by the Science and Technology Program of Guangzhou(No.202103000020).
文摘Objectives:Triple-negative breast cancer(TNBC)is the breast cancer subtype with the poorest prognosis.This study aimed to elucidate the molecular pathways through which isoliquiritigenin(ISL),a natural chalcone compound derived fromlicorice and other plant roots,targets interferon regulatory factor 5(IRF5)in TNBC.Methods:TNBC cell lines were cultured and subjected to IRF5 knockdown using short hairpin RNA.Cell proliferation was assessed by cell counting kit-8(CCK-8)assay and colony formation assays.Western blotting and quantitative reverse transcription polymerase chain reaction(RT-PCR)were employed to measure expression levels of IRF5,solute carrier family 7 member 5(SLC7A5),and indoleamine 2,3-dioxygenase 1(IDO1).Intracellular tryptophan and its metabolites were quantified using commercially available assay kits and high-performance liquid chromatography(HPLC).TNBC cells were treated with various concentrations of ISL to evaluate its effects on proliferation and tryptophanmetabolism.Results:IRF5 was highly expressed in TNBC cell lines.Silencing IRF5 significantly inhibited cellular proliferation and growth.Knockdown of IRF5 reduced the expression of SLC7A5 and IDO1,leading to decreased intracellular levels of tryptophan and its metabolites.ISL markedly suppressed TNBC cell proliferation and disrupted tryptophan metabolism in tumor cells.Conclusion:ISL may inhibit TNBC progression by downregulating IRF5 and interfering with SLC7A5/IDO1-mediated tryptophan metabolic reprogramming,suggesting a potential therapeutic mechanism for TNBC treatment.
文摘The gene encoded for tryptophan decarboxylase (TDC), which is the key enzyme in terpenoil indole alkaloids pathway, was targeted to different subcellular compartments and stably expressed in transgenic tobacco (Nicotiana tabacum L.) plants at the levels detected by Western blot and tryptamine accumulation analysis. It was shown that the TDC was located in subcellular compartments, the chloroplasts and cytosol. The recombinant TDC targeted to chloroplasts and cytosol in tobacco plants was effectively expressed as soluble protein by Western blot analysis and enzymatic assay. The level of tryptamine accumulation in chloroplast was higher than that in cytosol and very low in vacuole and endoplasmic reticulum (ER) to be hardly detected by Western blot analysis. It was indicated that the highest amount of tryptamine was in chloroplasts, lower in endoplasmic reticula and the lowest in vacuoles as compared to those in wild type plants. The TDC targeted to different subcellular compartments of tobacco plants and its expression level were studied by different nucleotide sequences coding signal peptides at 5'-end of tdc gene in order to know the effects of the TDC in compartmentation on its functionality.
文摘Drought stress in plants is accompanied by several metabolic changes. One of them is the appearance of <em>N</em>-malonyltryptophan (MT) during leaf wilting of many species, but there is a significant number of plant species in which the appearance of MT did not occur. Plants of some species were able to synthesize also <em>N</em>-acetyltryptophan (AT). Excised tomato leaves incubated with D-amino acids (including D-Trp) transform them into malonyl- and acetyl-derivatives even without water deficit. However, MT which appeared during water deficit has been shown to contain L-Trp. Amino acid—1-amino-cyclopropane-1-carboxylic acid (ACC) is also malonylated during water deficit, but other L-amino acids were not malonylated. <em>N</em>-malonyl transferases specific for Trp and ACC have been found in several plants. The existence of <em>N</em>-malonyltransferase specific to L-Trp and appeared during water deficit in plants forming MT is supposed, but clear experimental proof has not been obtained yet. Plants can transform MT applied exogenously into Trp and further to indole-3-acetic acid (IAA). But no evidence has been appeared up to now that endogenous MT may be a source of IAA. It is unknown till now why it is necessary for plants of many species to malonylate only Trp during water deficit. How MT metabolized in animals and if it affects them is also unknown. The necessity to use molecular-genetic approaches for the elucidation of the physiological significance of MT formation during water deficit is underlined.
文摘AIM: To evaluate how Helicobacter pylori(H. pylori) is able to evade the immune response and whether it enhances systemic immune tolerance against colorectal cancer.METHODS: This prospective randomized study involved 97 consecutive colorectal cancer patients and 108 cancer-free patients with extra-digestive diseases. Colorectal cancer and cancer-free patients were assigned into subgroups according to H. pylori Ig G seropositivity. Exposure to H. pylori was determined by Ig G seropositivity which was detected by enzyme linked immunoassay(ELISA). Serum neopterin levels were measured by ELISA. Serum tryptophan, kynurenine, and urinary biopterin concentrations were measured by high performance liquid chromatography. Serum nitrite levels were detected spectrophotometrically. Serum indoleamine 2,3-dioxygenase activity was estimated by the kynurenine to tryptophan ratio and by assessing the correlation between serum neopterin concentrations and the kynurenine to tryptophan ratio. The frequencies of increased serum kynurenine to tryptophan ratio of H. pylori seronegative and seropositive colorectal cancer subgroups were estimated by comparing them with the average kynurenine to tryptophan ratio of H. pylori seronegative tumor-free patients.RESULTS: Compared with respective controls, in both H. pylori seronegative and seropositive colorectal cancer patients, while serum tryptophan levels were decreased(controls vs patients; seronegative: 20.37 ± 0.89 μmol/L vs 15.71 ± 1.16 μmol/L, P < 0.05; seropositive: 20.71 ± 0.81 μmol/L vs 14.97 ± 0.79 μmol/L, P < 0.01) the kynurenine to tryptophan ratio was significantly increased(controls vs patients; seronegative: 52.85± 11.85 μmol/mmol vs 78.91 ± 8.68 μmol/mmol, P < 0.01, seropositive: 47.31 ± 5.93 μmol/mmol vs 109.65 ± 11.50 μmol/mmol, P < 0.01). Neopterin concentrations in cancer patients were significantly elevated compared with controls(P < 0.05). There was a significant correlation between serum neopterin levels and kynurenine/tryptophan in control and colorectal cancer patients groups(r s = 0.494, P = 0.0001 and r s= 0.293, P = 0.004, respectively). Serum nitrite levels of H. pylori seropositive cancer cases were significantly decreased compared with seropositive controls(controls vs patients; 26.04 ± 2.39 μmol/L vs 20.41 ± 1.48 μmol/L, P < 0.05) The decrease in the nitrite levels of H. pylori seropositive cancer patients may be attributed to excessive formation of peroxynitrite and other reactive nitrogen species.CONCLUSION: A significantly high kynurenine/tryptophan suggested that H. pylori may support the immune tolerance leading to cancer development, even without an apparent upper gastrointestinal tract disease.
基金financially supported by the earmarked fund for the China Agriculture Research System(CARS-36)the grant from the Science and Technology Support Program of Sichuan Province(13ZC2237)
文摘Oxidative stress can induce abnormal tryptophan metabolism. The present study was mainly conducted to determine the effect of dietary tryptophan levels on oxidative stress in the liver of weaned pigs challenged by diquat. A total of 36 PIC piglets weaned at 21 days of age were randomly allotted to 1 of 3 diets containing dietary tryptophan levels of 0.18, 0.30, and 0A5% for 14 d. On day 8, the piglets were injected intraperitoneally with sterile 0.9% NaCI solution or diquat （10 mg/kg body weight）. During the first 7 d of trial, increasing dietary tryptophan levels enhanced average daily gain （P = 0.09） and average daily feed intake （P = 0.08）, and decreased the feed efficiency （P 〈 0.05） of piglets. The growth performance was decreased by diquat injection （P 〈 0.05）. Diquat injection also decreased the activities of the superoxide dismutase （SOD） and glutathione peroxidase （GPx） in the plasma and liver （P 〈 0.05）, increased plasma malondialdehyde （MDA） （P 〈 0.05） and urea nitrogen （P 〈 0.05） concentrations, and enhanced MDA concentration （P = 0.09） and tryptophan 2,3-dioxygenase （TDO） activity （P = 0.07） in liver of piglets. Increasing dietary tryptophan levels could attenuate the effects of diquat injection on the MDA （P = 0.06） concentration and the activities of SOD （P = 0.09） and GPx （P = 0.05） of the liver, and plasma urea nitrogen （P = 0.06） concentration in the piglet. There was a synergistic role for increasing TDO activity in the liver between dietary tryptophan levels and diquat injection （P 〈 0.05）. These results suggest that increasing dietary tryptophan levels could attenuate the oxidative stress of the liver in weaned piglets intraperitoneally injected with diquat via enhancing the antioxidant capacity.
基金supported by the System for Poultry Production Technology,Beijing Innovation Research Team of Modern Agriculture(CARSPSTP)the National Key Technology R&D Program of China during the 12~(th) five-year plan(2012BAD39B04)
文摘Background： Highly automated cage-rearing systems are becoming increasingly popular in China. However, a high stocking density can cause oxidative stress and decrease broiler performance. The tryptophan （TRP） derivative 5-hydroxytryptophan （5-HT） has been shown to preserve membrane fluidity in birds suffering from oxidative stress Therefore, this experiment was conducted to determine the effects of dietan/TRP supplementation on performance, breast meat quality and oxidative stress in broilers reared in cages with a high or low stocking density. Methods： Female Arbor Acres broilers （25-d-old, n = 144） were randomly allocated to 1 of 4 treatments. The birds were fed a diet based on corn, soybean meal, cottonseed meal and corn gluten meal containing either 0.18 or 0.27% TRP and were housed with stocking densities of 11 or 15.4 birds/m2 in a 2 x 2 factorial experiment. Broiler performance was evaluated from d 25 to 42. Eight birds from each treatment were slaughtered on d 42 and plasma and breast muscle samples were collected to measure biochemical indices. Results： A higher stocking density tended to be associated with reduced weight gain （P 〈 0.10）, and significantly increased plasma glutamic-pyruvic transaminase （GPT） activity （P 〈 0.001）. Increased dietary TRP significantly reduced the activities of lactic dehydrogenase and GPT while increasing total cholesterol in the plasma （P 〈 0.01）, reducing drip loss of breast muscle （P 〈 0.10） and improving feed efficiency （P 〈 0.10）. Conclusions： An increase in dietary TRP, ].S-fold higher than the standard supplementation level, can alleviate oxidative stress as well as improve welfare and feed efficiency in broilers reared in cages with a high stocking density.
基金supported by National Natural Science Foundation of China(NSFC)(31802072)China Scholarship Council(CSC NO.202103250006)+1 种基金the Central Public-interest Scientific Institution Basal Research Fund(No.Y2022GH02&PJ01618301)State Key Laboratory of Animal Nutrition(2004DA125184G2102)。
文摘Background Pectin is a heteropolysaccharide that acts as an intestinal immunomodulator,promoting intestinal development and regulating intestinal flora in the gut.However,the relevant mechanisms remain obscure.In this study,pigs were fed a corn-soybean meal-based diet supplemented with either 5%microcrystalline cellulose(MCC)or 5%pectin for 3 weeks,to investigate the metabolites and anti-inflammatory properties of the jejunum.Result The results showed that dietary pectin supplementation improved intestinal integrity(Claudin-1,Occludin)and inflammatory response[interleukin(IL)-10],and the expression of proinflammatory cytokines(IL-1β,IL-6,IL-8,TNF-α)was down-regulated in the jejunum.Moreover,pectin supplementation altered the jejunal microbiome and tryptophan-related metabolites in piglets.Pectin specifically increased the abundance of Lactococcus,Enterococcus,and the microbiota-derived metabolites(skatole(ST),3-indoleacetic acid(IAA),3-indolepropionic acid(IPA),5-hydroxyindole-3-acetic acid(HIAA),and tryptamine(Tpm)),which activated the aryl hydrocarbon receptor(AhR)pathway.AhR activation modulates IL-22 and its downstream pathways.Correlation analysis revealed the potential relationship between metabolites and intestinal morphology,intestinal gene expression,and cytokine levels.Conclusion In conclusion,these results indicated that pectin inhibits the inflammatory response by enhancing the AhR-IL22-signal transducer and activator of transcription 3 signaling pathway,which is activated through tryptophan metabolites.
基金supported by a grant from the National Natural Science Foundation of China (No.81570402)a grant from the Jiangsu Key Laboratory of Xenotransplantation (BM2012116)+3 种基金grants from the Sanming Project of Medicine in Shenzhenthe Fund for High Level Medical Discipline Construction of Shenzhen (No.2016031638)the Shenzhen Foundation of Science and Technology (No.JCYJ20160229204849975 and GCZX2015043017281705)grant from the National Basic Research Program of China (2015CB559200)
文摘Unbalanced brain serotonin(5-HT) levels have implications in various behavioral abnormalities and neuropsychiatric disorders. The biosynthesis of neuronal 5-HT is regulated by the rate-limiting enzyme, tryptophan hydroxylase-2(TPH2). In the present study, the clustered regularly interspaced short palindromic repeat(CRISPR)/CRISPR-associated(Cas) system was used to target the Tph2 gene in Bama mini pig fetal fibroblasts. It was found that CRISPR/Cas9 targeting efficiency could be as high as 61.5%, and the biallelic mutation efficiency reached at38.5%. The biallelic modified colonies were used as donors for somatic cell nuclear transfer(SCNT) and 10 Tph2 targeted piglets were successfully generated. These Tph2 KO piglets were viable and appeared normal at the birth.However, their central 5-HT levels were dramatically reduced, and their survival and growth rates were impaired before weaning. These Tph2 KO pigs are valuable large-animal models for studies of 5-HT deficiency induced behavior abnomality.
文摘Objective To investigate changes of 5-hydroxytryptamine （5-HT） and its synthesis rate-limiting enzyme tryp-tophan hydroxylase （TPH） in the ventral horn of spinal cord after exercise-induced fatigue, and to further discuss the mecha- nism of exercise-induced central fatigue at spinal level. Methods Sixteen healthy adult Wistar rats were randomly divided into 2 groups： exercise-induced fatigue group and control group. Immunohistochemical staining for 5-HT and TPH in the ventral horn were performed and analysized quantitatively. The mean optic densities of 5-HT and TPH positive fibers or terminals were measured by computerized image analyzer. Results Both 5-HT and TPH positive fibers/terminals decreased in the exercise-induced fatigue group. The immunohistochemical staining was weaker and the mean optic densities decreased obviously in the fatigue group compared with those in the control group （P 〈 0.05）. Conclusion 5-HT and TPH in the ventral horn of spinal cord might be involved in exercise-induced fatigue.
文摘A feed trial was conducted with a total of 1 134 Beijing ducklings to study the optimum level of dietary lysine （Lys） （0.95, 1.10, 1.25%）, methionine （Met） （0.26, 0.46, 0.66%） and tryptophan （Trp） （0.20, 0.30, 0.40%） for those ducklings during a phase of 0-2 weeks. Ducklings were randomly allotted to 27 groups according to a 3 × 3× 3 factorial arrangement and fed a basal corn-soybean-peanut meal diet containing 20.26% CP, 12.45 MJ kg^-1 ME. The results from this study indicate that Lys affected body weight （P〈0.01）, feed intake （0-14 d） （P〈0.01）, but had no effect on feed/gain （0-14 d） （P〉0.05）, uric acid concentration （P 〉 0.05）. Methionine influenced body weight （P 〈 0.01）, feed/gain （P 〈 0.05）, and feed intake （P 〈 0.01）. Tryphtophan had no effect on indices measured. The requirement of the Lys and Met for Beijing ducklings of 0-2 weeks of age were 1.10 and 0.46%. The requirement of Trp for Beijing ducklings of 0-2 weeks of age was not more than 0.20%.
基金Supported by National Institutes of Health(NIH),Nos.DK099071 and DK083890the Career Development Award from the Crohn’s and Colitis Foundation of America(CCFA)
文摘Inflammatory bowel diseases(IBD), which comprise Crohn's disease and ulcerative colitis, are chronic intestinal disorders with an increased prevalence and incidence over the last decade in many different regions over the world. The etiology of IBD is still not well defined, but evidence suggest that it results from per-turbation of the homeostasis between the intestinal microbiota and the mucosal immune system, with the involvement of both genetic and environmental factors. Genome wide association studies, which involve large-scale genome-wide screening of potential polymorphism, have identified several mutations associated with IBD. Among them, Card9, a gene encoding an adapter molecule involved in innate immune response to fungi(via type C-lectin sensing) through the activation of IL-22 signaling pathway, has been identified as one IBD susceptible genes. Dietary compounds, which represent a source of energy and metabolites for gut bacteria, are also appreciated to be important actors in the etiology of IBD, for example by altering gut microbiota composition and by regulating the generation of short chain fatty acids. A noteworthy study published in the June 2016 issue of Nature Medicine by Lamas and colleagues investigates the interaction between Card9 and the gut microbiota in the generation of the microbiota-derived tryptophan metabolite. This study highlights the role of tryptophan in dampening intestinal inflammation in susceptible hosts.
