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SUMMARY OBJECTIVE: This study aimed to investigate the presence of indoleamine-2,3-dioxygenase and bacterial translocation after the administration of 3-aminobenzamide and infliximab in the TNBS model of rat colitis. METHODS: The study group was divided into five categories as follows: group 1: (control), group 2: colitis+saline, group 3: colitis+3-aminobenzamide, group 4: colitis+infliximab, and group 5: colitis+3-aminobenzamide+infliximab. Intestinal mesenteric cultures were incubated on specific agar media plates under aerobic and anaerobic conditions, bacterial translocation was evaluated and assessed as colony-forming units per gram of tissue. Colonic tissue samples were evaluated by Western blotting method to detect the presence of indoleamine-2,3-dioxygenase. RESULTS: The results obtained were as follows: group 1: normal gut flora; group 2: eight of nine samples had bacterial translocation, of which six of them had positive indoleamine-2,3-dioxygenase protein; group 3: five of nine samples had bacterial translocation, of which seven of them had positive indoleamine-2,3-dioxygenase; group 4: three of nine samples had bacterial translocation, of which seven of them had positive indoleamine-2,3-dioxygenase; and group 5: only one sample had exact indoleamine-2,3-dioxygenase protein. CONCLUSION: Altered expression of indoleamine-2,3-dioxygenase results in a lower bacterial translocation via infliximab compared with 3-aminobenzamide treatment. Combined treatments emphasized different approaches for the new molecules related to indoleamine-2,3-dioxygenase.
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There are two serious obstacles to tumor immunotherapy. Firstly, the immune response of the tumor is seriously reduced due to immunosuppressive tumor microenvironment (ITM) and low immunogenicity of tumor. The second obstacle is the dense and complex heterogeneous structures, which seriously prevent the nanoparticles (NPs) from penetrating deeper into tumor tissue. Immunogenic cell death (ICD) induced by doxorubicin (DOX) is an effective method to enhance tumor immune activity. However, interferon-γ (IFN-γ) secreted by cytotoxic T lymphocytes (CTL) after ICD induction would increase the expression of indoleamine 2,3-dioxygenase 1 (IDO1) and enhance ITM. IDO1 siRNA would reduce the expression of IDO1 protein, regulate the tumor immunosuppressive microenvironment and regulate ITM, so as to enhance the ICD effect of DOX. In this paper, a novel charge conversional, particle size reduction and highly penetrable NPs based on a pH sensitive copolymer poly(ethylene glycol)-poly-L-lysine-2,3-dimethylmaleic anhydride (mPEG-PLL-DMA, PLD) and polyamidoamine (PAMAM) dendrimers to achieve deep delivery of tumor tissue. DOX and IDO1 siRNA were encapsulated to achieve efficient tumor immunotherapy. Preparation and cell level experiments showed that PLD material had significant pH sensitivity. Results of 3D tumor penetrable experiment in vitro showed that adding the pH sensitive material PLD significantly improved the permeability of the preparation. In addition, 4T1 tumor model was established for BALB/c mice and all animal experiments were displayed in according with the requirements of the Animal Experiment Ethics Committee of Shenyang Pharmaceutical University. The results of in vivo efficacy experiments and tissue experiments evaluated that IDO1 siRNA significantly improved the ICD effect owing to DOX, so as to significantly inhibit tumor growth.
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Indoleamine 2, 3-dioxygenase (IDO) is one of the rate-limiting enzymes that degrade tryptophan (Trp) into kynurenine (Kyn). Inflammatory factor IFN-γ mediates tumor′s immune escape by activating the IDO signaling pathway, upregulating theKyn/Trp (K/T ratio) and suppressing the activity of both CD 8+T and regulatory T cells. Radiotherapy plays a major role in treating non-small cell lung cancer. It not only bi-directionally regulates immune response of the host, but also collaborates with immunosuppressive agents to kill tumors. Meanwhile, immune status of the host can affect the therapeutic effect of radiotherapy. In recent years, studies have shown that IDO activity levels change before and after radiotherapy and is related to clinical prognosis. Nevertheless, relevant mechanism remains unclear. This article aims to elucidate the application of IDO signaling pathway in radiotherapy for non-small cell lung cancer.
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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.
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Indoleamine 2, 3-dioxygenase (IDO) is an important immunoregulatory enzyme, which can degrade the level of the mammalian essential amino acid tryptophan (TRP), catalyze the initiation and rate-limiting steps through the kynurenine pathway, and produce a variety of metabolites to participate in the immune response. On the one hand, IDO plays an immunosuppressive role in microenvironment and thus leads to infection and immune escape of tumor cells; on the other hand, IDO also exerts an inhibitory effect on the pathogens such as bacteria and parasites and thus protects the body from the harm of pathogens to a certain extent. Therefore, IDO is considered an important medium with the role of a double-edged sword in the development and progression of various liver diseases. This article reviews the latest research advances in IDO in viral hepatitis, liver fibrosis, liver cirrhosis, liver cancer, and hepatic echinococcosis.
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We analyzed the anticancer effect and mechanism of the novel indoleamine 2,3-dioxygenase 1 (IDO1) inhibitor NLG-919 combined with temozolomide (TMZ) on human glioma cell lines. The anti-tumor activity of NLG-919 and temozolomide after single and combined treatments was detected by MTT assay. Colony formation assay, invasion assay and migration assays were used to detect the effects of NLG-919 and temozolomide alone or in combination on proliferation, invasion and migration of human glioma cells. A flow cytometry assay was used to detect cell apoptosis, cell cycle arrest, reactive oxygen species (ROS) production and mitochondrial membrane potential damage (JC-1). An immunofluorescence assay was used to detect the expression level of IDO1 and HPLC was used to detect the expression level of L-kynurenine (Kyn) to explore the anti-tumor mechanism of NLG-919 and temozolomide. The results show that NLG-919 had a weak in vitro inhibitory effect compared to that of temozolomide. The IC50 of NLG-919 on U251 cells and U87 after 72 h was 26.9 and 30.7 μmol·L-1, respectively. However, when NLG-919 was used in combination with temozolomide, its anti-glioma activity was significantly increased. Compared with the single treatment, the combination treatment had a potent ability to inhibit proliferation, invasion and migration of glioma cells. Combination treatment improved the capacity of temozolomide to induce cell cycle arrest and inhibit the growth of glioma cells. NLG-919 significantly down-regulated the expression and activity of IDO1 in glioma cells, and the inhibitory effect was improved after combination with temozolomide, and effectively blocked the production of Kyn through the metabolism of L-tryptophan (Trp). In conclusion, the IDO1 inhibitor NLG-919 and temozolomide showed synergistic effects in the anticancer therapy of human glioma cell lines.
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Impaired immunomodulatory capacity and oxidative stress are the key factors limiting the effectiveness of mesenchymal stem cell transplantation therapy. The present study was aimed to investigate the effects of jujuboside A (JuA) on the protective effect and immunomodulatory capacity of human umbilical cord mesenchymal stem cells (hUC-MSCs). Hydrogen peroxide was used to establish an oxidative damage model of hUC-MSCs, while PBMCs isolated from rats were used to evaluate the effect of JuA pre-treatment on the immunomodulatory capacity of hUC-MSCs. Furthermore, Hoechst 33258 staining, lactate dehydrogenase test, measurement of malondialdehyde, Western blot, high-performance liquid chromatography; and flow cytometry were performed. Our results indicated that JuA (25 μmol·L-1) promoted the proliferation of hUC-MSCs, but did not affect the differentiating capability of these cells. JuA pre-treatment inhibited apoptosis, prevented oxidative damage, and up-regulated the protein expression of nuclear factor-erythroid factor 2-related factor 2 and heme oxygenase 1 in hUC-MSCs in which oxidative stress was induced with H2O2. In addition, JuA pre-treatment enhanced the inhibitory effect of hUC-MSCs against abnormally activated PBMCs, which was related to stimulation of the expression and activity of indoleamine 2,3-dioxygenase. In conclusion, our results demonstrate that JuA pre-treatment can enhance the survival and immunomodulatory ability through pathways related to oxidative stress, providing a new option for the improvement of hUC-MSCs in the clinical setting.
Subject(s)
Animals , Humans , Rats , Cell Differentiation , Hydrogen Peroxide/metabolism , Mesenchymal Stem Cells , Oxidative Stress , Saponins , Umbilical Cord/metabolismABSTRACT
Indoleamine 2,3-dioxygenase 1 (IDO1) and tryptophan 2,3-dioxygenase (TDO) catalyze the initial and rate limiting step in the catabolism of tryptophan, which is related to tumor immune tolerance and poor prognosis in patients. In this regard, two enzymes have become important therapeutic targets for tumor immunotherapy. So far, nine IDO1 inhibitors and three IDO1/TDO dual inhibitors have entered clinical trials. This review summarizes the research progress of IDO1 inhibitors, TDO inhibitors and IDO1/TDO dual inhibitors from the perspective of medicinal chemistry.
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Indoleamine 2,3-dioxygenase 1 (IDO1) is the rate-limiting enzyme in the degradation of tryptophan to kynurenine. IDO1 is highly expressed in some tumor tissues. IDO1 can deplete tryptophan in tumor microenvironment, inhibit T cell function, and mediate the immune escape of tumor cells. Thus, IDO1 is considered a potential target of tumor immunotherapy. Currently, there are several IDO1 inhibitors in clinical research studies. The mechanism of IDO1-mediated tumor immune escape and the structure of IDO1 inhibitors are summarized in this review.
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OBJECTIVE Programmed death ligand-1 (PD-L1) and indoleamine 2, 3-dioxygenase 1 (IDO1) are immune checkpoints which can be induced by interferon-γ(IFN-γ) in the tumor microenvironment, leading to immune escape of tumors. Myricetin (MY) is a flavonoid distributed in many edible and medicinal plants. The aim of this study is to clarify the effect and the mechanism of MY on inhibiting IFN-γ-induced PD-L1 and IDO1 in lung cancer cells. METHODS Expressions of PD-L1 and major histocompatibility complex-I (MHC-I) were evaluated by flow cytometry and Western blotting, and the expression of IDO1 was measured by Western blotting. qRT-PCR was used to detect their mRNA levels. The function of T cells was evaluated using a co-culture system consist of lung cancer cells and the Jurkat-PD-1 T cell line that overexpressing PD-1. Molecular docking analysis, Western blotting and immunofluorescence were used for mechanism study. RESULTS MY potently inhibited IFN-γ-induced PD-L1 and IDO1 expression in human lung cancer cells, while didn't show obvious effect on the expression of MHC-I. In addition, MY restored the survival, proliferation, CD69 expression and interleukin-2 (IL-2) secretion of Jurkat-PD-1 T cells suppressed by IFN-γ-treated lung cancer cells in the co-culture system. Mechanistically, IFN-γ up-regulated PD-L1 and IDO1 at the transcriptional level through the JAK-STAT-IRF1 axis, which was targeted and inhibited by MY. CONCLUSION Our research revealed a new insight into the anti-tumor effects of MY which inhibited IFN-γ-induced PD-L1 and IDO1 expression, supporting the potential of MY in anti-tumor immunotherapy.
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Indoleamine 2, 3-dioxygenase (IDO) is an important immunoregulatory enzyme, which mediates immune effects by depleting tryptophan and producing multiple metabolites. Recently, the studies on the immune function of IDO have been mostly restricted in tumors and autoimmune diseases. Nevertheless, there are few studies pertaining to the role of IDO in parasitic diseases, notably in parasite-host immune interactions. This review mainly describes IDO-mediated immunoregulatory effects and its regulation of parasite-host interactions, so as to provide insights into the development of immune intervention schemes against parasitic diseases.
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RESUMEN En las gestantes obesas se han observado complicaciones, incluyendo prevalencia de abortos espontáneos y preeclampsia. Se ha propuesto que en parte estas complicaciones podrían explicarse por el ambiente inflamatorio que predomina en la obesidad. La enzima indolami-na-2,3-dioxigenasa 1 (IDO1) es inducida por la citoquina pro-inflamatoria IFN-y, por lo que se ha sugerido un incremento en su expresión en pacientes obesos. IDO1 desempeña funciones claves durante el embarazo, entre las que se encuentra el establecimiento de la tolerancia materno-fetal, la placentación y la regulación del flujo sanguíneo en la placenta. Hasta el momento los estudios que evalúan la expresión de IDO1 en la gestación en condiciones de obesidad son escasos. Por lo tanto, en esta revisión se propuso explorar las implicaciones derivadas de la alteración en la expresión de esta enzima en gestantes obesas. Según la evidencia disponible en la literatura, es posible que en gestantes obesas se presente un aumento en la expresión y la actividad de IDO1. Estas modificaciones podrían tener efectos deletéreos sobre la gestación y estar relacionada con las complicaciones que se observan en gestantes obesas.
ABSTRACT Women who have an obese body mass index are more likely to experience pregnancy complications, including spontaneous abortion and preeclampsia. It has been suggested that these complications are at least in part related to the pro-inflamatory environment that predominates in obesity. Indoleamine-2,3-dioxygenase 1 is an enzyme induced downstream IFN-y signalling, hence it has been suggested that it increases its expression and activity in obese patients. IDO1 exerts multiple functions in pregnancy, including its contribution to materno-fetal tolerance, placentation and regulation of placental blood flow. The evidence about IDO1 in pregnant obese women is scarce. Therefore, herein the implications of an overexpression of IDO1 in pregnant obese patients were explored. The evidence available at the moment suggests that it is possible that IDO1 increases its expression and activity in pregnant obese women contributing to the complications observed on these patients.
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BACKGROUND: Although Th2 immune activation is predominant in allergic diseases, neopterinlevels and indoleamine 2,3-dioxygenase (IDO)-1 activity (kynurenine:tryptophan ratio), which reflect Th1 immune activity, increase with interferon-gamma (IFN-γ) stimulation. We investigated neopterin, tryptophan, and kynurenine levels as biomarkersof the Th1 immune system activation and changes in IDO-1 activityin children with asthma, allergic rhinitis, and atopic dermatitis, as well as the relationship between these biomarkers and the total IgE level, age, and disease severity. METHODS: We divided 205 children (80 girls and 125 boys, four months to 17 years old) into four groups: controls, patients with asthma, patients with allergic rhinitis, and patients with atopic dermatitis. Peripheral venous blood samples were collected. Neopterin levels were determined by an enzyme immunoassay. Tryptophan and kynurenine levels were analyzed using HPLC. IDO-1 enzyme activity was calculated using tryptophan and kynurenine levels. IgE levels were measured. The Mann-Whitney U test, Kruskal-Wallis test, and Conover post-hoc method were used for statistical analysis. RESULTS: Neopterin, tryptophan, and kynurenine levels were higher and IgE levels and IDO-1 enzyme activity were lower in patients with asthma and allergic rhinitis than in controls (P < 0.05). Patients with atopic dermatitis showed higher neopterin, tryptophan, and kynurenine levels, higher IDO-1 activity, and lower IgE levels thancontrols (P < 0.05). CONCLUSIONS: The Th1/Th2 balance is disrupted in children with allergic diseases, concomitant with increased Th1-mediated immune response activation and reduced IgEproduction, which is promoted by Th2-type cytokines.
Subject(s)
Child , Female , Humans , Asthma , Biomarkers , Chromatography, High Pressure Liquid , Cytokines , Dermatitis, Atopic , Hypersensitivity , Immune System , Immunoenzyme Techniques , Immunoglobulin E , Indoleamine-Pyrrole 2,3,-Dioxygenase , Interferon-gamma , Kynurenine , Methods , Neopterin , Rhinitis, Allergic , TryptophanABSTRACT
Objective To investigate the effect of Immutol on inducing the immune tolerance of cardiac grafts in rat models. Methods A rat model of heterotopic abdominal heart transplantation was established. The recipient rats were divided into 5 groups: blank control group (n=6); dimethyl sulfoxide (DMSO) group (n=6), in which DMSO was administered until the cardiac graft arrest; Immutol group (n=6), in which Immutol was administered until the cardiac graft arrest; ciclosporin (CsA) group (n=10), in which CsA was administered for 20 d; combined group (n=13), in which Immutol was given for 60 d combined with CsA for 20 d. The survival time and pathological changes of cardiac grafts in each group were observed. The contents of serum interleukin (IL)-10 and interferon (IFN)-γ were detected. The expression levels of indoleamine 2, 3-dioxygenase (IDO) and fibrinogen-like protein 2(Fgl2) messenger RNA(mRNA) in heart tissues of rats in each group were measured. Results In the combined group, the cardiac grafts survived for >180 d and immune tolerance was induced. The pathological score of cardiac grafts in the combined group was significantly lower than that in the CsA group at postoperative 39 d (P < 0.05). The levels of serum IL-10 and IFN-γ in the combined group were significantly higher than those in the CsA group at 9 d and 39 d after operation (both P < 0.05). The content of serum IL-10 and IFN-γ in the combined group were gradually increased over time. At postoperative 39 d, the expression levels of IDO and Fgl2 mRNA in the combined group were significantly higher than those in the CsA group (both P < 0.05). The expression level of IDO mRNA in the combined group tended to gradually elevate after operation. In the combined group, the expression level of Fgl2 mRNA at postoperative 180 d was significantly higher than those at 9 d and 39 d after operation (both P < 0.05). Conclusions Combined administration of Immutol and CsA can effectively inhibit the incidence of acute rejection, and maintain the long-term survival of the cardiac grafts and induce immune tolerance after drug withdrawal.
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In this study, we used the tumor immunotherapy protein indoleamine 2,3-dioxygenase 1 (IDO1) as the target, and proposed an enzyme-cell-based tertiary IDO1 inhibitor high throughput screening platform. Firstly, the recombinant human IDO1 protein was expressed by genetic engineering and efficient IDO enzymatic screening system was established. Secondly, A172 cells stimulated with interferon-γ (IFNγ) or constructed plasmid which could highly express human IDO1 protein in HEK293 cells with transient transfection were used to construct the specific IDO1 cell based screening system. Finally, the effect of the compound on kynurenine and tryptophan in mouse plasma was determined by LC/MS/MS method on C57 mice, which could further verify the inhibitory effect of the selected compounds on IDO1 in vivo. The established and optimized enzyme-cell based screening model in this study can efficiently and effectively obtain IDO1 inhibitors in vitro, which lays a good foundation for the rapid development of clinical drugs. Procedures for animal study were performed with approval of the Animal Care and Use Committee of the Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College.
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Indoleamine 2,3-dioxygenase 1 (IDO1) is a key enzyme in the human tryptophan metabolism pathway, which can mediate tumor immune response. An IDO1 inhibitor would be a potential cancer immunotherapy drug. Based on the recently reported crystal of an IDO1 protein-inhibitor complex (PDBID: 6AZV), the structure of reported inhibitor, and by analyzing the interaction mode between the inhibitor and IDO1, new inhibitor molecules were designed and synthesized. All structures were confirmed by spectral data. Preliminary activity studies showed that compounds containing an azabiphenyl tetrazole structure (B1 and B2) and biphenyl compounds containing a sulfonamide structure (D1, D2 and D3) had excellent inhibitory activity of IDO1 at the enzyme and cell level, and were comparable or even better than the control drug INCB24360.
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Rheumatoid arthritis (RA) is an autoimmune disease characterized by excessive activation of autoreactive T cells and B cells, abundant production of autoantibodies and multiple joint involvement. Under the influence of heredity and environment, the disorder of innate immunity and adaptive immunity is the fundamental cause of the disease. In recent years, with rapid development of immunometabolism, milestone has been made in regulating the differentiation and function of immune cells through different energy metabolism pathways and related molecules. Many studies have shown that Trp-IDO1,2/TDO2-Kyn metabolic pathway mediates the pathogenesis and development of autoimmune diseases such as RA. This review summarizes the role of tryptophan (Trp), kynurenine (Kyn) and other metabolites in this metabolic pathway, as well as the role of rate-limiting enzymes indoleamine 2,3-dioxygenase 1 (IDO1), indoleamine 2,3-dioxygenase 2 (IDO2) and tryptophan-2,3-dioxygenase 2 (TDO2) in mediating RA inflammatory immune response and synovitis inflammation. This provides an important basis for elucidating the new pathological mechanism of RA and discovering new drug targets.
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PURPOSE: Breast cancer has become a major public health threat in the current society. Anthracycline doxorubicin (DOX) is a widely used drug in breast cancer chemotherapy. We aimed to investigate the immunogenic death of breast tumor cells caused by DOX, and detect the effects of combination of DOX and a small molecule inhibitor in tumor engrafted mouse model. METHODS: We used 4T1 breast cancer cells to examine the anthracycline DOX-mediated immunogenic death of breast tumor cells by assessing the calreticulin exposure and adenosine triphosphate and high mobility group box 1 release. Using 4T1 tumor cell-engrafted mouse model, we also detected the expression of indoleamine 2,3-dioxygenase (IDO) in tumor tissues after DOX treatment and further explored whether the specific small molecule IDO1 inhibitor NLG919 combined with DOX, can exhibit better therapeutic effects on breast cancer. RESULTS: DOX induced immunogenic cell death of murine breast cancer cells 4T1 as well as the upregulation of IDO1. We also found that treatment with NLG919 enhanced kynurenine inhibition in a dose-dependent manner. IDO1 inhibition reversed CD8+ T cell suppression mediated by IDO-expressing 4T1 murine breast cancer cells. Compared to the single agent or control, combination of DOX and NLG919 significantly inhibited the tumor growth, indicating that the 2 drugs exhibit synergistic effect. The combination therapy also increased the expression of transforming growth factor-β, while lowering the expressions of interleukin-12p70 and interferon-γ. CONCLUSION: Compared to single agent therapy, combination of NLG919 with DOX demonstrated better therapeutic effects in 4T1 murine breast tumor model. IDO inhibition by NLG919 enhanced the therapeutic efficacy of DOX in breast cancer, achieving synergistic effect.
Subject(s)
Animals , Mice , Adenosine Triphosphate , Breast Neoplasms , Breast , Calreticulin , Cell Death , Doxorubicin , Drug Therapy , Indoleamine-Pyrrole 2,3,-Dioxygenase , Kynurenine , Public Health , Therapeutic Uses , Up-RegulationABSTRACT
Objective To investigate the antidepressant effects of Chaihu Shugan Powder(CSP) on depressive rats induced by reserpine and its influences on the kynurenine (KYN),indoleamine 2,3-dioxyge-nase(IDO),interleukin-6(IL-6) and tumor necrosis factor-α( TNF-α). Methods Forty rats with similar behavior results were divide into 4 groups randomly,including Control group(Con),Model group(Res),Flu- oxetine group(Res+Flu) and Chaihu Shugan Powder group(CSP). The depressive rat model was established by intraperitoneal injection reserpine. The rats in Res+Flu group were administered with fluoxetine by intrap-eritoneal and rats in Res+CSP group were administered with CSP by intraperitoneal. After 14 days,the be-havior of rats was measured and then the rats were executed and sampled. The content of tryptophan and kynurenine in raphe nuclei tissue were detected. The mRNA expression level of IDO,IL-6,TNF-α in raphe nuclei tissue were detected. Results ( 1) Compared with Con group (( 81. 81 ± 36. 13) s, ( 83. 51 ± 5. 34)%), the swimming immobility time((150. 50±31. 45)s) in Res group increased(t=68. 7, P<0. 05) and the sucrose perference (59. 73±11. 30)%) in Res group decreased(t=23. 8,P<0. 05). Compared with Res group, the swimming immobility time in Res+Flu group((114. 90± 14. 29) s) and Res+CSP group ((111. 7±11. 34)s) decreased(t=35. 6,35. 8,both P<0. 05). Compared with Res group, the sucrose pref-erence in Res+Flu group((78. 21±10. 07)%) increased(t=18. 3, P<0. 05). (2)Compared with Con group (KYN/TRP:(0. 023±0. 016),IDO mRNA:(1. 00±0. 05),IL-6 mRNA:(1. 00±0. 58),TNF-α mRNA:(1. 00±0. 32)), the activity of IDO(KYN/TRP(0. 039±0. 003)) and the mRNA levels of IDO mRNA(3. 63± 0. 31),IL-6 mRNA(2. 36±0. 23),TNF-α mRNA( 3. 56± 0. 14) of Raphe Nuclei tissue in Res group were significantly increased (t=21. 2,12. 9,38. 3,19. 7,all P<0. 05). Compared with Res group, the activity of IDO(KYN/TRP(0. 030±0. 013)),the mRNA expression levels of IDO mRNA( 1. 56±0. 36),IL-6 mRNA (1. 62±0. 16),TNF-α mRNA(2. 64±0. 20)of Raphe Nuclei tissue in Res+Flu group were significantly de-creased(t=38. 8,15. 8,12. 8,26. 4,all P<0. 05). And compared with Res group,the activity of IDO( KYN/TRP(0. 028±0. 021)) ,the mRNA expression level of IDO mRNA( 1. 33± 0. 29),IL-6 mRNA(1. 36± 0. 34),TNF-α mRNA(1. 93±0. 21)of raphe nuclei tissue in Res+CSP group were also significantly decreased (t=23. 21,17. 3,19. 8,29. 8,all P<0. 05). Compared with Res+Flu group,the level of IDO mRNA and in-flammatory factors' mRNA in Res+CSP group were significantly decreased(t=18. 3,20. 8,31. 5,all P<0. 05). Conclusion Chaihu Shugan Powder has antidepressant effect,and the mechanism is related with de-creasing the inflammatory factors,inhibiting IDO activation and decreasing the IDO mRNA.
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Os inibidores de BRAF (iBRAFs) e de MEK (iMEK), inauguraram uma nova classe de medicamentos, a terapia direcionada, no combate ao melanoma metastático. Entretanto, os pacientes adquirem resistência ao tratamento em poucos meses. Além disso, a imunoterapia vem ganhando espaço no tratamento do câncer, incluindo o melanoma, porém, com alguns aspectos inexplorados. Dentro deste tema, a enzima IDO vem despertando um grande interesse pela participação nos mecanismos de imunotolerância, imunoescape e progressão tumoral. A IDO é responsável pelo consumo e depleção do triptofano, produzindo a quinurenina. Ela está presente em diversos tipos celulares, incluindo células do sistema imune e células tumorais. Este trabalho objetivou avaliar a expressão de IDO durante a progressão da doença - desde do nevo até o melanoma metastático e também avaliar a regulação de IDO induzido por IFN-γ após tratamento com iBRAF em linhagens parentais e resistentes ao iBRAF, buscando-se os mecanismos moleculares. Por fim, objetivou-se entender os efeitos do 1-metil-triptofano (1-MT), um inibidor de IDO, tanto na sua capacidade de inibir a atividade de IDO quanto na sua influência na capacidade clonogênica. O estudo de bioinformática sobre o repositório público GSE12391 mostrou que o nível de expressão gênica de IDO foi superior nos estágios mais avançado da doença. Além disso, todas amostras de melanoma primário de pacientes apresentaram a imunomarcação de IDO, enquanto que nenhuma amostra de nevo apresentou tal marcação. Adicionalmente, a ocorrência de IDO se deu nos infiltrados linfoides, em células mononucleares do sistema imune. Duas análises de bioinformática de expressão gênica demonstraram que a IDO estava expressa positivamente na fase de resistência ao iBRAF. Ademais, os resultados de expressão proteica mostraram que a inibição de via MAPK (tanto por iBRAF quanto por iMEK) conseguiu modular a expressão de IDO, sendo que a maioria das linhagens apresentou uma diminuição de IDO. A atividade de IDO, medida através da produção de quinurenina, por HPLC se mostrou em consonância com os resultados de expressão proteica, exceto pela linhagem WM164 que não apresentou atividade enzimática, embora a proteína estivesse presente. Por fim, o 1-MT conseguiu inibir de maneira eficiente a enzima IDO, bloqueando a produção de quinurenina. Além de que, o 1-MT reduziu a capacidade clonogênica de maneira dose-dependente. Portanto, conclui-se que a expressão de IDO é crescente conforme a progressão do melanoma, que a inibição da via MAPK regulou a expressão de IDO e que o 1-MT reduz a capacidade clonogênica, além da sua função primária de inibir IDO
BRAF and MEK inhibitors (BRAFi and MEKi) has launched a new class of medication, the target therapy, to combat metastatic melanoma. Nevertheless, patients acquired resistance to the treatment in few months. Additionally, immunotherapy has been gaining space in cancer treatment, including melanoma, but some aspects need to be explored. Inside this theme, IDO enzyme has called the attention due to its participation in the mechanisms of immune tolerance, scape and tumor progression. IDO is responsible for tryptophan consume e depletion, producing kynurenine. It is present in different cells, including cells from immune system and tumor cells. This work purposed evaluate IDO expression during disease progression - since nevus until metastatic melanoma and also, evaluate IFN-γ-induced IDO regulation after BRAFi treatment in parental and resistant melanoma cell lines, seeking the molecular mechanisms. Lastly, it was evaluated the effects of 1-methyltryptopahn (1-MT), an IDO inhibitor, by its ability to inhibit IDO and also by its influency on the clonogenic capability. Bioinformatic study performed on GSE12391 showed that gene expression level of IDO was superior in the most advanced stages of the disease. Additionally, all sample of patient's primary melanoma presented IDO immunostaining, whereas, no nevus samples presented such staining. Besides, IDO occurrence was in the lymphoid infiltrates, in mononuclear cells from immune system. Two bioinformatic analysis of gene expression demonstrated that IDO was differentially overexpressed during BRAFi resistance stage. Moreover, protein expression results presented that MAPK pathway inhibition (both by BRAFi and by MEKy) was able to modulate IDO expression, and most of the cell lines presented an IDO downregulation. IDO activity, measured through kynurenine production, by HPLC was consonant with protein expression results, except by WM164 cell line, which did not present enzymatic activity, albeit the protein was present. By the end, 1-MT could inhibit efficiently IDO enzyme, blocking kynurenine production. Furthermore, 1-MT reduced clonogenic capability in a dosedependent manner. Therefore, it was concluded that IDO expression increases along with melanoma progression, MAPK pathway inhibition regulated IDO expression and 1-MT reduced clonogenic capability, besides its primary function of IDO inhibitor