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1.
Sci Rep ; 14(1): 12734, 2024 06 03.
Artículo en Inglés | MEDLINE | ID: mdl-38830969

RESUMEN

The early screening of depression is highly beneficial for patients to obtain better diagnosis and treatment. While the effectiveness of utilizing voice data for depression detection has been demonstrated, the issue of insufficient dataset size remains unresolved. Therefore, we propose an artificial intelligence method to effectively identify depression. The wav2vec 2.0 voice-based pre-training model was used as a feature extractor to automatically extract high-quality voice features from raw audio. Additionally, a small fine-tuning network was used as a classification model to output depression classification results. Subsequently, the proposed model was fine-tuned on the DAIC-WOZ dataset and achieved excellent classification results. Notably, the model demonstrated outstanding performance in binary classification, attaining an accuracy of 0.9649 and an RMSE of 0.1875 on the test set. Similarly, impressive results were obtained in multi-classification, with an accuracy of 0.9481 and an RMSE of 0.3810. The wav2vec 2.0 model was first used for depression recognition and showed strong generalization ability. The method is simple, practical, and applicable, which can assist doctors in the early screening of depression.


Asunto(s)
Depresión , Voz , Humanos , Depresión/diagnóstico , Masculino , Femenino , Inteligencia Artificial , Adulto
2.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 41(1): 9-16, 2024 Feb 25.
Artículo en Chino | MEDLINE | ID: mdl-38403599

RESUMEN

For the increasing number of patients with depression, this paper proposes an artificial intelligence method to effectively identify depression through voice signals, with the aim of improving the efficiency of diagnosis and treatment. Firstly, a pre-training model called wav2vec 2.0 is fine-tuned to encode and contextualize the speech, thereby obtaining high-quality voice features. This model is applied to the publicly available dataset - the distress analysis interview corpus-wizard of OZ (DAIC-WOZ). The results demonstrate a precision rate of 93.96%, a recall rate of 94.87%, and an F1 score of 94.41% for the binary classification task of depression recognition, resulting in an overall classification accuracy of 96.48%. For the four-class classification task evaluating the severity of depression, the precision rates are all above 92.59%, the recall rates are all above 92.89%, the F1 scores are all above 93.12%, and the overall classification accuracy is 94.80%. The research findings indicate that the proposed method effectively enhances classification accuracy in scenarios with limited data, exhibiting strong performance in depression identification and severity evaluation. In the future, this method has the potential to serve as a valuable supportive tool for depression diagnosis.


Asunto(s)
Inteligencia Artificial , Depresión , Humanos , Depresión/diagnóstico , Reconocimiento en Psicología , Habla
3.
PLoS Biol ; 21(8): e3002227, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37531320

RESUMEN

Phosphoinositide-dependent kinase-1 (PDK1) is a master kinase of the protein A, G, and C (AGC) family kinases that play important roles in regulating cancer cell proliferation, survival, and metabolism. Besides phosphorylating/activating AKT at the cell membrane in a PI3K-dependent manner, PDK1 also exhibits constitutive activity on many other AGC kinases for tumor-promoting activity. In the latter case, PDK1 protein levels dominate its activity. We previously reported that MAPK4, an atypical MAPK, can PI3K-independently promote AKT activation and tumor growth. Here, using triple-negative breast cancer (TNBC) cell models, we demonstrate that MAPK4 can also enhance PDK1 protein synthesis, thus phosphorylate/activate PDK1 substrates beyond AKT. This new MAPK4-PDK1 axis alone lacks vigorous tumor-promoting activity but cooperates with our previously reported MAPK4-AKT axis to promote tumor growth. Besides enhancing resistance to PI3K blockade, MAPK4 also promotes cancer cell resistance to the more stringent PI3K and PDK1 co-blockade, a recently proposed therapeutic strategy. Currently, there is no MAPK4 inhibitor to treat MAPK4-high cancers. Based on the concerted action of MAPK4-AKT and MAPK4-PDK1 axis in promoting cancer, we predict and confirm that co-targeting AKT and PDK1 effectively represses MAPK4-induced cancer cell growth, suggesting a potential therapeutic strategy to treat MAPK4-high cancers.


Asunto(s)
Proteínas Quinasas Dependientes de 3-Fosfoinosítido , Proteínas Quinasas Activadas por Mitógenos , Neoplasias , Proteínas Proto-Oncogénicas c-akt , Humanos , Proteínas Quinasas Dependientes de 3-Fosfoinosítido/metabolismo , Proteínas Quinasas Activadas por Mitógenos/metabolismo , Neoplasias/tratamiento farmacológico , Fosfatidilinositol 3-Quinasas/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Transducción de Señal
4.
Phys Med Biol ; 68(11)2023 05 30.
Artículo en Inglés | MEDLINE | ID: mdl-37172613

RESUMEN

Objective. Convolutional neural networks have been widely adopted for medical image segmentation with their outstanding feature representation capabilities. As the segmentation accuracy gets constantly updated, the complexity of networks increases as well. Complex networks can achieve better performance but require more parameters and are hard to train with limited resources, while lightweight models are faster but cannot fully utilize the contextual information of medical images. In this paper, we focus on better balancing the efficiency and accuracy.Approach. We propose a correlation-enhanced lightweight network (CeLNet) for medical image segmentation, which adopts a siamese structure for weight sharing and parameter saving. Through the feature reuse and feature stacking of parallel branches, a point-depth convolution parallel block (PDP Block) is proposed to reduce the model parameters and computational cost while improving the feature extraction capability of encoder. A relation module is also designed to extract feature correlations of input slices, which utilizes global and local attention to enhance feature connections, while reducing feature differences through element subtraction, and finally obtains contextual information of associated slices to improve the segmentation performance.Main results. We conduct extensive experiments on the LiTS2017, MM-WHS and ISIC2018 datasets, and the proposed model consumes merely 5.18M parameters but achieves excellent segmentation performance, specifically, a DSC of 0.9233 in LiTS2017 dataset, an average DSC of 0.7895 on MM-WHS dataset and an average DSC of 0.8401 on ISIC2018 dataset.Significance. CeLNet achieves state-of-the-art performance in multiple datasets while ensuring lightweight.


Asunto(s)
Procesamiento de Imagen Asistido por Computador , Redes Neurales de la Computación
5.
Heliyon ; 9(4): e14728, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37025774

RESUMEN

Respiratory activity is the most important basic life activity of human body, respiratory state detection is of great practical significance. Based on the characteristic of high correlation between the change of tidal volume and the change of abdominal displacement, a method of detecting respiratory status through abdominal displacement data is proposed. The method uses a gas pressure sensor to collect the tidal volume in the steady state of the subject once, which is used as the baseline data. The abdominal displacement data of the subject in the three breathing states of slow breathing, steady breathing and rapid breathing were collected with an acceleration sensor. The warp path distance between the lung and abdominal data in the three different states was calculated, this warp path distance together with the period extracted from the abdominal data is used as a two-dimensional feature and input to the support vector machine classifier. The experiments show that the accuracy of the classification results reaches 90.23%. The method only needs to measure the lung data once in smooth breathing state, and the subsequent continuous detection is achieved by measuring the displacement of the abdomen only. This method has the advantages of stable and reliable acquisition results, low implementation cost and simplified wearing method, and has high practicality.

6.
Cell Chem Biol ; 29(7): 1174-1186.e7, 2022 07 21.
Artículo en Inglés | MEDLINE | ID: mdl-35316658

RESUMEN

Phospholipids are ligands for nuclear hormone receptors (NRs) that regulate transcriptional programs relevant to normal physiology and disease. Here, we demonstrate that mimicking phospholipid-NR interactions is a robust strategy to improve agonists of liver receptor homolog-1 (LRH-1), a therapeutic target for colitis. Conventional LRH-1 modulators only partially occupy the binding pocket, leaving vacant a region important for phospholipid binding and allostery. Therefore, we constructed a set of molecules with elements of natural phospholipids appended to a synthetic LRH-1 agonist. We show that the phospholipid-mimicking groups interact with the targeted residues in crystal structures and improve binding affinity, LRH-1 transcriptional activity, and conformational changes at a key allosteric site. The best phospholipid mimetic markedly improves colonic histopathology and disease-related weight loss in a murine T cell transfer model of colitis. This evidence of in vivo efficacy for an LRH-1 modulator in colitis represents a leap forward in agonist development.


Asunto(s)
Colitis , Fosfolípidos , Receptores Citoplasmáticos y Nucleares , Animales , Colitis/tratamiento farmacológico , Ligandos , Ratones , Fosfolípidos/uso terapéutico , Receptores Citoplasmáticos y Nucleares/agonistas
7.
Nature ; 593(7857): 147-151, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33828301

RESUMEN

Bile acids are lipid-emulsifying metabolites synthesized in hepatocytes and maintained in vivo through enterohepatic circulation between the liver and small intestine1. As detergents, bile acids can cause toxicity and inflammation in enterohepatic tissues2. Nuclear receptors maintain bile acid homeostasis in hepatocytes and enterocytes3, but it is unclear how mucosal immune cells tolerate high concentrations of bile acids in the small intestine lamina propria (siLP). CD4+ T effector (Teff) cells upregulate expression of the xenobiotic transporter MDR1 (encoded by Abcb1a) in the siLP to prevent bile acid toxicity and suppress Crohn's disease-like small bowel inflammation4. Here we identify the nuclear xenobiotic receptor CAR (encoded by Nr1i3) as a regulator of MDR1 expression in T cells that can safeguard against bile acid toxicity and inflammation in the mouse small intestine. Activation of CAR induced large-scale transcriptional reprogramming in Teff cells that infiltrated the siLP, but not the colon. CAR induced the expression of not only detoxifying enzymes and transporters in siLP Teff cells, as in hepatocytes, but also the key anti-inflammatory cytokine IL-10. Accordingly, CAR deficiency in T cells exacerbated bile acid-driven ileitis in T cell-reconstituted Rag1-/- or Rag2-/- mice, whereas pharmacological activation of CAR suppressed it. These data suggest that CAR acts locally in T cells that infiltrate the small intestine to detoxify bile acids and resolve inflammation. Activation of this program offers an unexpected strategy to treat small bowel Crohn's disease and defines lymphocyte sub-specialization in the small intestine.


Asunto(s)
Ácidos y Sales Biliares/metabolismo , Regulación de la Expresión Génica , Intestino Delgado/metabolismo , Receptores Citoplasmáticos y Nucleares/metabolismo , Linfocitos T/metabolismo , Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/biosíntesis , Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/genética , Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/metabolismo , Animales , Linfocitos T CD4-Positivos/metabolismo , Receptor de Androstano Constitutivo , Enfermedad de Crohn/metabolismo , Femenino , Ileítis/metabolismo , Inflamación/metabolismo , Interleucina-10/biosíntesis , Interleucina-10/genética , Intestino Delgado/citología , Ratones
8.
Nat Commun ; 11(1): 4457, 2020 09 08.
Artículo en Inglés | MEDLINE | ID: mdl-32901017

RESUMEN

Innate lymphoid cells (ILCs) and CD4+ T cells produce IL-22, which is critical for intestinal immunity. The microbiota is central to IL-22 production in the intestines; however, the factors that regulate IL-22 production by CD4+ T cells and ILCs are not clear. Here, we show that microbiota-derived short-chain fatty acids (SCFAs) promote IL-22 production by CD4+ T cells and ILCs through G-protein receptor 41 (GPR41) and inhibiting histone deacetylase (HDAC). SCFAs upregulate IL-22 production by promoting aryl hydrocarbon receptor (AhR) and hypoxia-inducible factor 1α (HIF1α) expression, which are differentially regulated by mTOR and Stat3. HIF1α binds directly to the Il22 promoter, and SCFAs increase HIF1α binding to the Il22 promoter through histone modification. SCFA supplementation enhances IL-22 production, which protects intestines from inflammation. SCFAs promote human CD4+ T cell IL-22 production. These findings establish the roles of SCFAs in inducing IL-22 production in CD4+ T cells and ILCs to maintain intestinal homeostasis.


Asunto(s)
Ácidos Grasos Volátiles/inmunología , Microbioma Gastrointestinal/inmunología , Inmunidad Innata , Interleucinas/biosíntesis , Animales , Butiratos/inmunología , Butiratos/metabolismo , Butiratos/farmacología , Linfocitos T CD4-Positivos/efectos de los fármacos , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD4-Positivos/microbiología , Citrobacter rodentium , Colitis/inmunología , Colitis/microbiología , Colitis/prevención & control , Infecciones por Enterobacteriaceae/inmunología , Infecciones por Enterobacteriaceae/microbiología , Infecciones por Enterobacteriaceae/prevención & control , Ácidos Grasos Volátiles/metabolismo , Ácidos Grasos Volátiles/farmacología , Microbioma Gastrointestinal/fisiología , Inhibidores de Histona Desacetilasas/farmacología , Humanos , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Técnicas In Vitro , Interleucinas/deficiencia , Interleucinas/genética , Linfocitos/efectos de los fármacos , Linfocitos/inmunología , Linfocitos/microbiología , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Ratones Transgénicos , Regiones Promotoras Genéticas , Receptores de Hidrocarburo de Aril/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Interleucina-22
9.
J Immunol ; 205(7): 1944-1952, 2020 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-32859726

RESUMEN

The role of IL-21, produced mainly by Th17 cells and T follicular helper cells, has been intensively investigated in B cell differentiation and Ab class switch. However, how IL-21 regulates memory IgA+ B cell development and memory IgA responses in the intestines is still not completely understood. In this study, we found the total IgA+ B cells as well as CD38+CD138-IgA+ memory B cells were significantly increased in intestinal lamina propria (LP) of TCRßxδ-/- mice after transfer of microbiota Ag-specific Th17 cells but not Th1 cells. Although IL-21R-/- mice or IL-17R-/- mice showed decreased Ag-specific memory IgA production in the intestines upon infection with Citrobacter rodentium, the percentage of IgA+CD38+CD138- memory B cells in Peyer's patches and LP was decreased only in IL-21R-/- mice, but not in IL-17R-/- mice, after reinfection with C. rodentium compared with wild-type mice. Blockade IL-21 in vivo suppressed intestinal C. rodentium-specific IgA production as well as IgA+CD38+CD138- memory B cells in Peyer's patches and LP. Furthermore, IL-21 significantly induced B cell IgA production in vitro, with the increased expression of genes related with class-switching and memory B cell development, including Aicda, Ski, Bmi1, and Klf2. Consistently, Aicda and Ski expression was decreased in B cells of IL-21R-/- mice after C. rodentium reinfection. In conclusion, our study demonstrated that IL-21 promotes intestinal memory IgA B cell development, possibly through upregulating differentiation-related and class switching-related genes, indicating a potential role of IL-21 in memory IgA+ B cell responses in the intestines.


Asunto(s)
Linfocitos B/inmunología , Citrobacter rodentium/fisiología , Infecciones por Enterobacteriaceae/inmunología , Interleucinas/metabolismo , Mucosa Intestinal/inmunología , Receptores de Interleucina-21/metabolismo , Células Th17/inmunología , Animales , Células Cultivadas , Inmunoglobulina A/metabolismo , Cambio de Clase de Inmunoglobulina/genética , Memoria Inmunológica , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Receptores de Interleucina-21/genética
10.
J Med Chem ; 62(24): 11022-11034, 2019 12 26.
Artículo en Inglés | MEDLINE | ID: mdl-31419141

RESUMEN

As a key regulator of metabolism and inflammation, the orphan nuclear hormone receptor, liver receptor homolog-1 (LRH-1), has potential as a therapeutic target for diabetes, nonalcoholic fatty liver disease, and inflammatory bowel diseases (IBD). Discovery of LRH-1 modulators has been difficult, in part due to the tendency for synthetic compounds to bind unpredictably within the lipophilic binding pocket. Using a structure-guided approach, we exploited a newly discovered polar interaction to lock agonists in a consistent orientation. This enabled the discovery of the first low nanomolar LRH-1 agonist, one hundred times more potent than the best previous modulator. We elucidate a novel mechanism of action that relies upon specific polar interactions deep in the LRH-1 binding pocket. In an organoid model of IBD, the new agonist increases expression of LRH-1-controlled steroidogenic genes and promotes anti-inflammatory gene expression changes. These studies constitute major progress in developing LRH-1 modulators with potential clinical utility.


Asunto(s)
Diseño de Fármacos , Desarrollo de Medicamentos , Enfermedades Metabólicas/tratamiento farmacológico , Receptores Citoplasmáticos y Nucleares/agonistas , Humanos , Enfermedades Metabólicas/metabolismo , Estructura Molecular , Relación Estructura-Actividad
11.
J Immunol ; 203(1): 282-292, 2019 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-31076530

RESUMEN

The gut microbiota has been shown critical for mucosal adjuvant activity of cholera toxin (CT), a potent mucosal adjuvant. However, the mechanisms involved remain largely unknown. In this study, we report that depletion of gut bacteria significantly decreased mucosal and systemic Ab responses in mice orally immunized with OVA and CT. Feeding mice short-chain fatty acids (SCFAs) promoted Ab responses elicited by CT, and, more importantly, rescued Ab responses in antibiotic-treated mice. In addition, mice deficient in GPR43, a receptor for SCFAs, showed impaired adjuvant activity of CT. Administering CT did not promote SCFA production in the intestines; thus, SCFAs facilitated but did not directly mediate the adjuvant activity of CT. SCFAs promoted B cell Ab production by promoting dendritic cell production of BAFF and ALDH1a2, which induced B cell expression of IFN regulatory factor 4, Blimp1, and XBP1, the plasma B cell differentiation-related genes. Furthermore, when infected with Citrobacter rodentium, GPR43-/- mice exhibited decreased Ab responses and were more susceptible to infection, whereas the administration of SCFAs promoted intestinal Ab responses in wild-type mice. Our study thereby demonstrated a critical role of gut microbiota and their metabolite SCFAs in promoting mucosal adjuvant activity of CT through GPR43.


Asunto(s)
Adyuvantes Inmunológicos/metabolismo , Linfocitos B/inmunología , Toxina del Cólera/metabolismo , Citrobacter rodentium/fisiología , Células Dendríticas/inmunología , Infecciones por Enterobacteriaceae/inmunología , Ácidos Grasos Volátiles/metabolismo , Microbioma Gastrointestinal/fisiología , Receptores Acoplados a Proteínas G/metabolismo , Familia de Aldehído Deshidrogenasa 1/metabolismo , Animales , Formación de Anticuerpos , Factor Activador de Células B/metabolismo , Diferenciación Celular , Inmunidad Mucosa , Ratones , Ratones Noqueados , Comunicación Paracrina , Receptores Acoplados a Proteínas G/genética , Retinal-Deshidrogenasa/metabolismo
12.
Artículo en Inglés | MEDLINE | ID: mdl-30831322

RESUMEN

BACKGROUND & AIMS: Regenerating islet-derived protein (REG3γ), an antimicrobial peptide, typically expressed by intestinal epithelial cells (IEC), plays crucial roles in intestinal homeostasis and controlling gut microbiota. However, the mechanisms that regulate IEC expression of REG3γ are still largely unclear. In this study, we investigated whether and how interleukin (IL) 33, an alarmin produced by IEC in response to injury, regulates REG3γ expression in IEC, thus contributing to intestinal homeostasis. METHODS: IEC were isolated from wild-type and IL33-/- mice to determine expression of REG3γ and other antimicrobial peptides by quantitative real-time polymerase chain reaction and Western blot. IEC cell lines were used for mechanistic studies. 16S rRNA pyrosequencing analysis was used for measuring gut microbiota. Citrobacter rodentium was used for enteric infections. RESULTS: The expression of REG3γ, but not ß-defensins, in IECs of IL33-/- mice was significantly lower than wild-type mice. IL33 treatment induced IEC expression of REG3γ in both mice and human cell lines. Mechanistically, IL33 activated STAT3, mTOR, and ERK1/2 in IEC. Inhibition of these pathways abrogated IL33-induction of REG3γ. IL33-/- mice demonstrated higher bacteria loads and altered microbiota composition. IL33 did not directly inhibit bacterial growth, but promoted wild-type, not REG3γKO, IECs to kill bacteria in vitro. Consistently, C rodentium infection induced IEC IL33 expression, and IL33-/- mice demonstrated an impaired bacterial clearance with C rodentium infection. CONCLUSIONS: Our study demonstrated that IL33, which is produced by IEC in response to injury and inflammatory stimulation, in turn promotes IEC expression of REG3γ, and controls the gut microbiota of the host.


Asunto(s)
Bacterias/clasificación , Interleucina-33/metabolismo , Mucosa Intestinal/metabolismo , Proteínas Asociadas a Pancreatitis/metabolismo , ARN Ribosómico 16S/genética , Animales , Bacterias/genética , Bacterias/aislamiento & purificación , Células Cultivadas , Citrobacter rodentium/inmunología , Citrobacter rodentium/patogenicidad , Células Epiteliales/citología , Células Epiteliales/metabolismo , Microbioma Gastrointestinal , Regulación de la Expresión Génica , Células HT29 , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Mucosa Intestinal/citología , Ratones , Filogenia , Transducción de Señal
13.
Inflamm Bowel Dis ; 25(9): 1450-1461, 2019 08 20.
Artículo en Inglés | MEDLINE | ID: mdl-30918945

RESUMEN

BACKGROUND: How the gut microbiota regulates intestinal homeostasis is not completely clear. Gut microbiota metabolite short-chain fatty acids (SCFAs) have been reported to regulate T-cell differentiation. However, the mechanisms underlying SCFA regulation of T-cell differentiation and function remain to be investigated. METHODS: CBir1, an immunodominant microbiota antigen, transgenic T cells were treated with butyrate under various T-cell polarization conditions to investigate butyrate regulation of T-cell differentiation and the mechanism involved. Transfer of butyrate-treated CBir T cells into Rag1-/- mice was performed to study the in vivo role of such T cells in inducing colitis. RESULTS: Although butyrate promoted Th1 cell development by promoting IFN-γ and T-bet expression, it inhibited Th17 cell development by suppressing IL-17, Rorα, and Rorγt expression. Interestingly, butyrate upregulated IL-10 production in T cells both under Th1 and Th17 cell conditions. Furthermore, butyrate induced T-cell B-lymphocyte-induced maturation protein 1 (Blimp1) expression, and deficiency of Blimp1 in T cells impaired the butyrate upregulation of IL-10 production, indicating that butyrate promotes T-cell IL-10 production at least partially through Blimp1. Rag1-/- mice transferred with butyrate-treated T cells demonstrated less severe colitis, compared with transfer of untreated T cells, and administration of anti-IL-10R antibody exacerbated colitis development in Rag-/- mice that had received butyrate-treated T cells. Mechanistically, the effects of butyrate on the development of Th1 cells was through inhibition of histone deacetylase but was independent of GPR43. CONCLUSIONS: These data indicate that butyrate controls the capacity of T cells in the induction of colitis by differentially regulating Th1 and Th17 cell differentiation and promoting IL-10 production, providing insights into butyrate as a potential therapeutic for the treatment of inflammatory bowel disease.


Asunto(s)
Butiratos/farmacología , Diferenciación Celular/inmunología , Colitis/etiología , Microbioma Gastrointestinal/fisiología , Mucosa Intestinal/metabolismo , Células TH1/inmunología , Células Th17/inmunología , Animales , Diferenciación Celular/efectos de los fármacos , Colitis/metabolismo , Colitis/patología , Interferón gamma/metabolismo , Interleucina-10/metabolismo , Interleucina-17/inmunología , Interleucina-17/metabolismo , Mucosa Intestinal/microbiología , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Miembro 3 del Grupo F de la Subfamilia 1 de Receptores Nucleares/metabolismo , Proteínas de Dominio T Box/metabolismo , Células TH1/efectos de los fármacos , Células TH1/metabolismo , Células TH1/patología , Células Th17/efectos de los fármacos , Células Th17/metabolismo , Células Th17/patología
14.
Nat Commun ; 9(1): 3555, 2018 09 03.
Artículo en Inglés | MEDLINE | ID: mdl-30177845

RESUMEN

T-cells are crucial in maintanence of intestinal homeostasis, however, it is still unclear how microbiota metabolites regulate T-effector cells. Here we show gut microbiota-derived short-chain fatty acids (SCFAs) promote microbiota antigen-specific Th1 cell IL-10 production, mediated by G-protein coupled receptors 43 (GPR43). Microbiota antigen-specific Gpr43-/- CBir1 transgenic (Tg) Th1 cells, specific for microbiota antigen CBir1 flagellin, induce more severe colitis compared with wide type (WT) CBir1 Tg Th1 cells in Rag-/- recipient mice. Treatment with SCFAs limits colitis induction by promoting IL-10 production, and administration of anti-IL-10R antibody promotes colitis development. Mechanistically, SCFAs activate Th1 cell STAT3 and mTOR, and consequently upregulate transcription factor B lymphocyte-induced maturation protein 1 (Blimp-1), which mediates SCFA-induction of IL-10. SCFA-treated Blimp1-/- Th1 cells produce less IL-10 and induce more severe colitis compared to SCFA-treated WT Th1 cells. Our studies, thus, provide insight into how microbiota metabolites regulate Th1 cell functions to maintain intestinal homeostasis.


Asunto(s)
Colitis/inmunología , Ácidos Grasos Volátiles/inmunología , Microbioma Gastrointestinal/inmunología , Interleucina-10/inmunología , Receptores Acoplados a Proteínas G/inmunología , Células TH1/inmunología , Animales , Ácidos Grasos Volátiles/metabolismo , Flagelina/inmunología , Expresión Génica , Técnicas de Inactivación de Genes , Homeostasis , Ratones , Factor 1 de Unión al Dominio 1 de Regulación Positiva/genética , Receptores Acoplados a Proteínas G/genética , Factor de Transcripción STAT3/inmunología , Serina-Treonina Quinasas TOR/inmunología , Regulación hacia Arriba
15.
J Immunol ; 201(8): 2492-2501, 2018 10 15.
Artículo en Inglés | MEDLINE | ID: mdl-30171165

RESUMEN

Neutrophils are the first responders to sites of inflammation when the intestinal epithelial barrier is breached and the gut microbiota invade. Despite current efforts in understanding the role of neutrophils in intestinal homeostasis, the complex interactions between neutrophils and intestinal epithelial cells (IECs) is still not well characterized. In this study, we demonstrated that neutrophils enhanced production of amphiregulin (AREG), a member of the EGFR ligand family, by IECs, which promoted IEC barrier function and tissue repair. Depletion of neutrophils resulted in more severe colitis in mice because of decreased AREG production by IECs upon dextran sodium sulfate (DSS) insult. Administration of AREG restored epithelial barrier function and ameliorated colitis. Furthermore, neutrophil-derived TGF-ß promoted AREG production by IECs. Mechanistically, TGF-ß activated MEK1/2 signaling, and inhibition of MEK1/2 abrogated TGF-ß-induced AREG production by IECs. Collectively, these findings reveal that neutrophils play an important role in the maintenance of IEC barrier function and homeostasis.


Asunto(s)
Anfirregulina/metabolismo , Colitis/inmunología , Enfermedades Inflamatorias del Intestino/inmunología , Mucosa Intestinal/fisiología , Neutrófilos/fisiología , Factor de Crecimiento Transformador beta/metabolismo , Animales , Células Cultivadas , Colitis/inducido químicamente , Sulfato de Dextran , Modelos Animales de Enfermedad , Femenino , Homeostasis , Humanos , MAP Quinasa Quinasa 1/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Transducción de Señal
16.
Oncotarget ; 9(10): 9073-9087, 2018 Feb 06.
Artículo en Inglés | MEDLINE | ID: mdl-29507675

RESUMEN

Cytostatic drugs used in cancer therapy were evaluated for their capacity to inhibit Echinococcus multilocularis metacestode growth and proliferation. Metacestode tissues were exposed in vitro to docetaxel, doxorubicin, navelbine, paclitaxel, and vorinostat for 1 week, then incubated in drug-free culture, and thereafter metacestodes were injected into the peritoneum of Meriones unguiculatus. Magnetic resonance imaging (MRI) and simultaneous positron emission tomography (PET) were applied to monitor in vivo growth of drug-exposed E. multilocularis in Meriones. At 3 month p.i., docetaxel (at 10 µM, 5 µM and 2 µM) inhibited in vivo growth and proliferation of E. multilocularis, and at 5 months p.i., only in the 2 µM docetaxel exposure group 0.3 cm 3 of parasite tissue was found. With paclitaxel and navelbine the in vivo growth of metacestodes was suppressed until 3 months p.i., thereafter, parasite tissues enlarged up to 3 cm 3 in both groups. E. multilocularis tissues of more than 10 g developed in Meriones injected with metacestodes which were previously exposed in vitro to doxorubicin, navelbine, paclitaxel or vorinostat. In Meriones infected with metacestodes previously exposed to docetaxel, the in vivo grown parasite tissues weighted 0.2 g. In vitro cultured E. multilocularis metacestodes exposed to docetaxel did not produce vesicles until 7 weeks post drug exposure, while metacestodes exposed to doxorubicin, navelbine and vorinostat proliferated continuously. In summary, docetaxel, and less efficaciously paclitaxel, inhibited in vivo and in vitro parasite growth and proliferation, and these observations suggest further experimental studies with selected drug combinations which may translate into new treatment options against alveolar echinococcosis.

17.
Mucosal Immunol ; 11(3): 752-762, 2018 05.
Artículo en Inglés | MEDLINE | ID: mdl-29411774

RESUMEN

The antimicrobial peptides (AMP) produced by intestinal epithelial cells (IEC) play crucial roles in the regulation of intestinal homeostasis by controlling microbiota. Gut microbiota has been shown to promote IEC expression of RegIIIγ and certain defensins. However, the mechanisms involved are still not completely understood. In this report, we found that IEC expression levels of RegIIIγ and ß-defensins 1, 3, and 4 were lower in G protein-coupled receptor (GPR)43-/- mice compared to that of wild-type (WT) mice. Oral feeding with short-chain fatty acids (SCFA) promoted IEC production of RegIIIγ and defensins in mice. Furthermore, SCFA induced RegIIIγ and ß-defensins in intestinal epithelial enteroids generated from WT but not GPR43-/- mice. Mechanistically, SCFA activated mTOR and STAT3 in IEC, and knockdown of mTOR and STAT3 impaired SCFA induction of AMP production. Our studies thus demonstrated that microbiota metabolites SCFA promoted IEC RegIIIγ and ß-defensins in a GPR43-dependent manner. The data thereby provide a novel pathway by which microbiota regulates IEC expression of AMP and intestinal homeostasis.


Asunto(s)
Microbioma Gastrointestinal/fisiología , Mucosa Intestinal/fisiología , Receptores Acoplados a Proteínas G/metabolismo , Animales , Antiinfecciosos/metabolismo , Ácidos Grasos Volátiles/metabolismo , Homeostasis , Inmunidad Innata , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Proteínas Asociadas a Pancreatitis/genética , Proteínas Asociadas a Pancreatitis/metabolismo , Receptores Acoplados a Proteínas G/genética , Factor de Transcripción STAT3/metabolismo , Serina-Treonina Quinasas TOR/metabolismo , beta-Defensinas/genética , beta-Defensinas/metabolismo
18.
Mol Immunol ; 73: 98-111, 2016 05.
Artículo en Inglés | MEDLINE | ID: mdl-27062712

RESUMEN

Prenatal exposure to parasite antigens or allergens will influence the profile and strength of postnatal immune responses, such contact may tolerize and increase susceptibility to future infections or sensitize to environmental allergens. Exposure in utero to parasite antigens will distinctly alter cellular gene expression in newborns. Gene microarrays were applied to study gene expression in umbilical cord blood cell (UCBC) from parasite-exposed (Para-POS) and non-exposed (Para-NEG) neonates. UCBC were activated with antigens of helminth (Onchocerca volvulus), amoeba (Entamoeba histolytica) or allergens of mite (Dermatophagoides farinae). When UCBC from Para-POS and Para-NEG newborns were exposed to helminth antigens or allergens consistent differences occurred in the expression of genes encoding for MHC class I and II alleles, signal transducers of activation and transcription (STATs), cytokines, chemokines, immunoglobulin heavy and light chains, and molecules associated with immune regulation (SOCS, TLR, TGF), inflammation (TNF, CCR) and apoptosis (CASP). Expression of genes associated with innate immune responses were enhanced in Para-NEG, while in Para-POS, the expression of MHC class II and STAT genes was reduced. Within functional gene networks for cellular growth, proliferation and immune responses, Para-NEG neonates presented with significantly higher expression values than Para-POS. In Para-NEG newborns, the gene cluster and pathway analyses suggested that gene expression profiles may predispose for the development of immunological, hematological and dermatological disorders upon postnatal helminth parasite infection or allergen exposure. Thus, prenatal parasite contact will sensitize without generating aberrant inflammatory immune responses, and increased pro-inflammatory but decreased regulatory gene expression profiles will be present in those neonates lacking prenatal parasite antigen encounter.


Asunto(s)
Amebiasis/complicaciones , Helmintiasis/complicaciones , Complicaciones Parasitarias del Embarazo/inmunología , Efectos Tardíos de la Exposición Prenatal/inmunología , Amebiasis/genética , Amebiasis/inmunología , Animales , Antígenos Dermatofagoides/inmunología , Antígenos Helmínticos/inmunología , Antígenos de Protozoos/inmunología , Femenino , Sangre Fetal , Helmintiasis/genética , Helmintiasis/inmunología , Humanos , Recién Nacido , Análisis de Secuencia por Matrices de Oligonucleótidos , Reacción en Cadena de la Polimerasa , Embarazo , Complicaciones Parasitarias del Embarazo/genética , Efectos Tardíos de la Exposición Prenatal/genética , Transcriptoma/inmunología
19.
J Inflamm (Lond) ; 12: 5, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25698903

RESUMEN

BACKGROUND: In sub-Saharan Africa poly-parasite infections are frequently observed in children, and with poly-parasitism modulating immune mechanisms, mediated by cytokines and chemokines, are required to prevent overwhelming inflammation and host tissue damage. We analyzed in children co-infected with helminthes and protozoan parasites their cellular production of regulatory and pro-inflammatory cytokines and chemokines in response to parasite antigens and allergens. METHODS: Intestinal and intravascular parasite infections were detected in stool and urines samples. The in vitro cellular cytokine and chemokine responses of peripheral blood mononuclear cells (PBMC) to parasite antigens and allergens were analysed in children (n = 87) with single and poly-parasite infection, and skin prick test reactivity to fungus and mite allergens was determined in singly and poly-parasitized children (n = 509). RESULTS: In children Entamoeba histolytica/dispar (62%), Necator americanus (31%), Schistosoma haematobium (28%), S. mansoni (21%), Hymenolepis nana (2%) and Strongyloides stercoralis (1%) were diagnosed. Singly infected were 37%, 47% were positive for 2 or more parasite species and 16% were infection-free. When PBMC were stimulated in vitro with parasite antigens and allergens, regulatory-type cytokine IL-27 and alarmin-type IL-33 enhanced with poly-parasite infections whilst IL-10 and pro-inflammatory MIP3-α/CCL20 and MIG/CXCL9 were produced in similar amounts in singly or poly-parasitized children. The co-stimulation in vitro of PBMC with mite allergens and Ascaris lumbricoides antigens depressed the allergen-induced pro-inflammatory IL-27, IL-33 and MIP3-α/CCL20 responses while regulatory IL-10 remained unaffected. Post albendazole and/or praziquantel treatment, the cellular release of IL-10, IL-33, MIP3-α/CCL20 and MIG/CXCL9 lessened significantly in all children infection groups. Skin prick test (SPT) reactivity to fungus Aspergillus fumigatus and mite Dermatophagoides pteronyssinus allergens was investigated in 509 children, and positive SPT responses were found in 23% of the infection-free, and in 47%, 53% and 56% of the singly, doubly and poly-parasite infected, respectively. CONCLUSIONS: In children co-infected with helminthes and protozoan parasites a mixed cellular response profile of both inflammatory and regulatory chemokines and cytokines was stimulated by individual antigens and allergens, pro-inflammatory cytokines and chemokines enhanced with an increasing number of parasite infections, and in poly-parasitized children skin prick test reactivity to allergens extracts was highest.

20.
Med Microbiol Immunol ; 203(3): 185-93, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24509604

RESUMEN

Metacestode larvae of the tapeworm Echinococcus multilocularis can cause alveolar echinococcosis (AE), a severe parasitic disease in man, which, if it remains untreated, may cause organ failure and death. Spontaneous and parasite antigen-induced cellular responses were studied in patients with cured, stable, and progressive AE to differentiate the response profiles between the distinct states of infection. Antibody reactivity was evaluated in AE patients with cured, stable, and progressive disease. The spontaneous cellular release of pro-inflammatory IL-31 and IL-33 was clearly depressed in all AE patients, while regulatory IL-27, anti-inflammatory SDF-1/CXCL12, and eosinophil granulocyte attracting Eotaxin-1, Eotaxin-2, and Eotaxin-3 (CCL11, CCL24, CCL26) were enhanced with disease progression. Such distinctive response profiles could be applied for monitoring of AE disease progression or regression. E. multilocularis metacestode (Em) antigens (entire metacestode EmAg as well as EmVesicles) stimulated in vitro IL-31, IL-33, Eotaxin-1, Eotaxin-3, and CXCL12 cytokine and chemokine responses, which were similarly present in all AE patient groups, while regulatory IL-27 was suppressed and pro-inflammatory Eotaxin-2 was enhanced. E. multilocularis metacestode-specific IgG1, IgG3, and IgE responses progressively diminished with regression from active to stable and cured AE. IgG2 and IgG4 reactivity remained similarly high in stable and progressive cases, and lessened only with cured AE. Antibody reactivity against E. multilocularis vesicle antigen distinctively separated between cured, stable, or progressive AE, with the exception of IgG4. In sum, the combined and longitudinal study of several cytokines and chemokines, together with the evaluation of E. multilocularis vesicle-specific antibody responses, should provide a better understanding of the immune response during progression and regression of AE, and may help to improve the staging of AE patients.


Asunto(s)
Anticuerpos Antihelmínticos/sangre , Citocinas/metabolismo , Equinococosis Hepática/inmunología , Echinococcus multilocularis/inmunología , Leucocitos Mononucleares/inmunología , Animales , Antígenos Helmínticos/inmunología , Equinococosis , Equinococosis Hepática/tratamiento farmacológico , Femenino , Humanos , Inmunoglobulina E/sangre , Inmunoglobulina G/sangre , Masculino , Persona de Mediana Edad
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