RESUMEN
INTRODUCTION: Gut microbiota plays a critical role in the regulation of immune homeostasis. Accordingly, several autoimmune disorders have been associated with dysbiosis in the gut microbiota. Notably, the dysbiosis associated with central nervous system (CNS) autoimmunity involves a substantial reduction of bacteria belonging to Clostridia clusters IV and XIVa, which constitute major producers of short-chain fatty acids (SCFAs). Here we addressed the role of the surface receptor-mediated effects of SCFAs on mucosal T-cells in the development of CNS autoimmunity. METHODS: To induce CNS autoimmunity, we used the mouse model of experimental autoimmune encephalomyelitis (EAE) induced by immunization with the myelin oligodendrocyte glycoprotein (MOG)-derived peptide (MOG35-55 peptide). To address the effects of GPR43 stimulation on colonic TCRαß+ T-cells upon CNS autoimmunity, mucosal lymphocytes were isolated and stimulated with a selective GPR43 agonist ex vivo and then transferred into congenic mice undergoing EAE. Several subsets of lymphocytes infiltrating the CNS or those present in the gut epithelium and gut lamina propria were analysed by flow cytometry. In vitro migration assays were conducted with mucosal T-cells using transwells. RESULTS: Our results show a sharp and selective reduction of intestinal propionate at the peak of EAE development, accompanied by increased IFN-γ and decreased IL-22 in the colonic mucosa. Further analyses indicated that GPR43 was the primary SCFAs receptor expressed on T-cells, which was downregulated on colonic TCRαß+ T-cells upon CNS autoimmunity. The pharmacologic stimulation of GPR43 increased the anti-inflammatory function and reduced the pro-inflammatory features in several TCRαß+ T-cell subsets in the colonic mucosa upon EAE development. Furthermore, GPR43 stimulation induced the arrest of CNS-autoreactive T-cells in the colonic lamina propria, thus avoiding their infiltration into the CNS and dampening the disease development. Mechanistic analyses revealed that GPR43-stimulation on mucosal TCRαß+ T-cells inhibits their CXCR3-mediated migration towards CXCL11, which is released from the CNS upon neuroinflammation. CONCLUSIONS: These findings provide a novel mechanism involved in the gut-brain axis by which bacterial-derived products secreted in the gut mucosa might control the CNS tropism of autoreactive T-cells. Moreover, this study shows GPR43 expressed on T-cells as a promising therapeutic target for CNS autoimmunity.
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Encefalomielitis Autoinmune Experimental , Receptores de Antígenos de Linfocitos T alfa-beta , Ratones , Animales , Autoinmunidad , Disbiosis , Sistema Nervioso Central , Glicoproteína Mielina-Oligodendrócito/toxicidad , Péptidos , Ratones Endogámicos C57BLRESUMEN
Cardiovascular diseases are the leading cause of mortality and morbidity in the Region of the Americas, and hypertension is one of the main risk factors. In 2018, Argentina began implementing the HEARTS Initiative in five primary health care centers, through the National Plan for the Prevention and Control of Arterial Hypertension. This study presents the impact its implementation has had on the indicators of effective coverage, treatment, combination therapy, and control. The HEARTS Initiative has multiple components; these include training health teams, reassigning tasks based on the transfer of clinical competencies, providing automatic and clinically validated blood pressure measurement devices, and using a single standardized treatment protocol. A longitudinal data model (generalized estimating equation analysis) was used, and the information from the five health centers was grouped using weighted averages according to the size of the population under coverage. Analysis of the results was stratified into two time periods delimited by the imposition of restrictions due to COVID-19. During the first period of 18 months, significant improvement was observed in treatment (5.9%; p<0.01) and combination therapy (13.4%; p<0.01), with no significant change in coverage (8.4%; p=0.87) and with a paradoxical decrease in control (-3.3%; p=0.02). When the period of restrictions was compared to the previous period, a generalized reduction was observed in all indicators, particularly coverage (-23.6%; p<0.01) and control (-12.5%; p<0.01). However, treatment and combination therapy levels remained above baseline values (1.7%; p<0.01 and 5.4%; p<0.01, respectively).
As doenças cardiovasculares são a principal causa de morbimortalidade, e a hipertensão, seu principal fator de risco. Em 2018, a Argentina começou a implementar a Iniciativa HEARTS em 5 centros de atenção primária à saúde por meio do Plano Nacional de Prevenção e Controle da Hipertensão Arterial. Este estudo apresenta o impacto de sua implementação nos indicadores de cobertura efetiva, tratamento, tratamento combinado e controle. A Iniciativa HEARTS inclui vários componentes. Entre eles, se destacam a capacitação das equipes de saúde, a reorganização das tarefas com base na transferência de competências clínicas, a disponibilização de aparelhos automáticos e clinicamente validados para aferição da pressão arterial e a utilização de um único protocolo padronizado de tratamento. Foi utilizado um modelo de equações de estimativas generalizadas para a análise de dados longitudinais, e as informações dos 5 centros de saúde foram agrupadas por meio de médias ponderadas de acordo com o tamanho da população coberta. A análise dos resultados foi estratificada em dois períodos de tempo delimitados pela irrupção das restrições em virtude da COVID-19. Durante os primeiros 18 meses, houve melhora significativa no tratamento (5,9%; p<0,01) e no tratamento combinado (13,4%; p<0,01), sem mudança significativa na cobertura (8,4%; p=0,87) e com uma diminuição paradoxal no controle (−3,3%; p=0,02). Durante as restrições e em relação ao período anterior, verificou-se redução generalizada em todos os indicadores, principalmente na cobertura (−23,6%; p<0,01) e no controle (−12,5%; p<0,01). No entanto, os níveis de tratamento e tratamento combinado persistiram acima dos valores basais (1,7%; p<0,01 e 5,4%; p<0,01, respectivamente).
RESUMEN
BACKGROUND: Recent evidence has shown dopamine as a major regulator of inflammation. Accordingly, dopaminergic regulation of immune cells plays an important role in the physiopathology of inflammatory disorders. Multiple sclerosis (MS) is an inflammatory disease involving a CD4+ T-cell-driven autoimmune response to central nervous system (CNS) derived antigens. Evidence from animal models has suggested that B cells play a fundamental role as antigen-presenting cells (APC) re-stimulating CD4+ T cells in the CNS as well as regulating T-cell response by mean of inflammatory or anti-inflammatory cytokines. Here, we addressed the role of the dopamine receptor D3 (DRD3), which displays the highest affinity for dopamine, in B cells in animal models of MS. METHODS: Mice harbouring Drd3-deficient or Drd3-sufficient B cells were generated by bone marrow transplantation into recipient mice devoid of B cells. In these mice, we compared the development of experimental autoimmune encephalomyelitis (EAE) induced by immunization with a myelin oligodendrocyte glycoprotein (MOG)-derived peptide (pMOG), a model that leads to CNS-autoimmunity irrespective of the APC-function of B cells, or by immunization with full-length human MOG protein (huMOG), a model in which antigen-specific activated B cells display a fundamental APC-function in the CNS. APC-function was assessed in vitro by pulsing B cells with huMOG-coated beads and then co-culturing with MOG-specific T cells. RESULTS: Our data show that the selective Drd3 deficiency in B cells abolishes the disease development in the huMOG-induced EAE model. Mechanistic analysis indicates that although DRD3-signalling did not affect the APC-function of B cells, DRD3 favours the CNS-tropism in a subset of pro-inflammatory B cells in the huMOG-induced EAE model, an effect that was associated with higher CXCR3 expression. Conversely, the results show that the selective Drd3 deficiency in B cells exacerbates the disease severity in the pMOG-induced EAE model. Further analysis shows that DRD3-stimulation increased the expression of the CNS-homing molecule CD49d in a B-cell subset with anti-inflammatory features, thus attenuating EAE manifestation in the pMOG-induced EAE model. CONCLUSIONS: Our findings demonstrate that DRD3 in B cells exerts a dual role in CNS-autoimmunity, favouring CNS-tropism of pro-inflammatory B cells with APC-function and promoting CNS-homing of B cells with anti-inflammatory features. Thus, these results show DRD3-signalling in B cells as a critical regulator of CNS-autoimmunity.
Asunto(s)
Autoinmunidad/fisiología , Linfocitos B/metabolismo , Dopamina/metabolismo , Encefalomielitis Autoinmune Experimental/metabolismo , Receptores de Dopamina D3/metabolismo , Secuencia de Aminoácidos , Animales , Linfocitos B/inmunología , Células Cultivadas , Sistema Nervioso Central/inmunología , Sistema Nervioso Central/metabolismo , Dopamina/inmunología , Encefalomielitis Autoinmune Experimental/genética , Encefalomielitis Autoinmune Experimental/inmunología , Femenino , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Ratones Transgénicos , Receptores de Dopamina D3/genética , Receptores de Dopamina D3/inmunologíaRESUMEN
In Argentina, cardiovascular disease (CVD) represents the first cause of mortality, but effective coverage for CVD prevention is low. Strategies based on behavioral economics are emerging worldwide as key pieces to increase the effectiveness of CVD prevention approaches. The aim of this study was to evaluate whether the implementation of two strategies based on financial incentives and framing increased attendance to clinical visits as proposed by the national program for CVD risk factors management among the uninsured and poor population with moderate or high CVD risk in Argentina. We conducted a cluster randomized trial in nine primary care clinics (PCCs) in Argentina. Three PCCs were assigned to financial incentives, 3 to framing-text messages (SMS) and 3 to usual care. The incentive scheme included a direct incentive for attending the first clinical visit and the opportunity to participate in a lottery when attending a second clinical visit. The framing-text messages group received messages with a gain-frame format. The main outcome was the proportion of participants who attended the clinical visits. A total of 918 individuals with a risk ≥10% of suffering a CVD event within the next 10 years were recruited to participate in the study. The financial incentive group had a significantly higher percentage of participants who attended the first (59.0% vs 33.9%, pË 0.001) and the follow up visit (34.4% and 16.6%, pË 0.001) compared to control group. However, the framing-SMS group did not show significant differences compared to the control group. TRIAL REGISTRATION: This study is registered at www.clinicaltrials.govNCT03300154.
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Enfermedades Cardiovasculares , Motivación , Atención Ambulatoria , Argentina , Enfermedades Cardiovasculares/epidemiología , Enfermedades Cardiovasculares/prevención & control , Factores de Riesgo de Enfermedad Cardiaca , Humanos , Factores de Riesgo , Poblaciones VulnerablesRESUMEN
Floating ferns of the genus Salvinia have great potential for phytoremediation of heavy metals. To date, the effect of essential metals on the accumulation and transport of toxic metals by aquatic ferns has not been suitably established. The aim of this study was to compare the ability of floating leaves of Salvinia minima and Salvinia rotundifolia species to accumulate Cr from Cr(VI solutions containing very low (0.02 mg L-1) and low (5 mg L-1) Zn concentrations. After 7-day metal-exposure period, results showed that Zn increased Cr accumulation in S. minima leaves whereas in S. rotundifolia decreased significantly. Contrarily Zn accumulation did not show great differences between species. This fact may indicate that Zn interfere Cr(VI) uptake by S. rotundifolia. Bioconcentration factor (BCF) and translocation factor (TF) were affected differently by Zn in both Salvinia species. Membrane stability index (MSI) of both Salvinia species was decreased significantly by 5 mg L-1 Zn concentration. Zn ions also increased hydrogen peroxide accumulation in fronds of Salvinia species. Total thiols (TT), non-protein thiols (NPT) and protein-bound thiols (PBT) were differentially affected by Cr(VI) and Zn ions. This study provides evidences on the involvement of different mechanisms against Cr(VI)/Zn toxicity in S. minima and S rotundifolia species.
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Metales Pesados , Contaminantes Químicos del Agua , Biodegradación Ambiental , Cromo , Compuestos de Sulfhidrilo , Contaminantes Químicos del Agua/toxicidad , ZincRESUMEN
Dopamine receptor D3 (DRD3) expressed on CD4(+) T cells is required to promote neuroinflammation in a murine model of Parkinson's disease. However, how DRD3 signaling affects T cell-mediated immunity remains unknown. In this study, we report that TCR stimulation on mouse CD4(+) T cells induces DRD3 expression, regardless of the lineage specification. Importantly, functional analyses performed in vivo using adoptive transfer of OVA-specific OT-II cells into wild-type recipients show that DRD3 deficiency in CD4(+) T cells results in attenuated differentiation of naive CD4(+) T cells toward the Th1 phenotype, exacerbated generation of Th2 cells, and unaltered Th17 differentiation. The reciprocal regulatory effect of DRD3 signaling in CD4(+) T cells favoring Th1 generation and impairing the acquisition of Th2 phenotype was also reproduced using in vitro approaches. Mechanistic analysis indicates that DRD3 signaling evokes suppressor of cytokine signaling 5 expression, a negative regulator of Th2 development, which indirectly favors acquisition of Th1 phenotype. Accordingly, DRD3 deficiency results in exacerbated eosinophil infiltration into the airways of mice undergoing house dust mite-induced allergic response. Interestingly, our results show that, upon chronic inflammatory colitis induced by transfer of naive CD4(+) T cells into lymphopenic recipients, DRD3 deficiency not only affects Th1 response, but also the frequency of Th17 cells, suggesting that DRD3 signaling also contributes to Th17 expansion under chronic inflammatory conditions. In conclusion, our findings indicate that DRD3-mediated signaling in CD4(+) T cells plays a crucial role in the balance of effector lineages, favoring the inflammatory potential of CD4(+) T cells.
Asunto(s)
Inflamación Neurogénica/inmunología , Enfermedad de Parkinson/inmunología , Receptores de Dopamina D3/metabolismo , Proteínas Supresoras de la Señalización de Citocinas/metabolismo , Células TH1/inmunología , Células Th17/inmunología , Animales , Diferenciación Celular , Células Cultivadas , Modelos Animales de Enfermedad , Regulación de la Expresión Génica , Humanos , Activación de Linfocitos , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Ratones Transgénicos , Receptores de Antígenos de Linfocitos T/genética , Receptores de Antígenos de Linfocitos T/metabolismo , Receptores de Dopamina D3/genética , Transducción de Señal , Proteínas Supresoras de la Señalización de Citocinas/genética , Balance Th1 - Th2RESUMEN
BACKGROUND: The dual potential to promote tolerance or inflammation when facing self-antigens makes dendritic cells (DCs) fundamental players in autoimmunity. There is an association between smoking and DCs maturation in patients with rheumatoid arthritis (RA). However, ethnicity is a key factor in autoimmune disorders. AIM: To evaluate phenotypic and functional alterations of DCs obtained from Chilean patients with RA as compared to healthy controls (HC). In second term, to compare the inflammatory behaviour of DCs between smoker and non-smoker patients. MATERIAL AND METHODS: Monocyte-derived DCs and T-cells were obtained from blood samples isolated from 30 HC and 32 RA-patients, 14 of which were currently smokers and 18 non-smokers. Several maturation surface markers were evaluated in DCs, including HLA-DR, CD40, CD80, CD83 and CD86. Furthermore, autologous co-cultures of DCs and T-cells were carried out and then T-cell proliferation, and expansion of Th1, Th17 and Tregs were analysed. RESULTS: Compared with HC, RA-patients displayed increased HLA-DR expression in DCs, which was manifested mainly in patients with moderate-to- high disease activity scores (DAS28). Furthermore, RA-patients presented a stronger Th17-expansion and a correlation between DAS28 and Th1-expansion. Both effects were mainly observed in patients in remission or with a low DAS28. Moreover, smoker RA-patients displayed enhanced HLA-DR and CD83 expression in DCs as well as an exacerbated Th17-expansion and a correlation between DAS28 and Th1-expansion. CONCLUSIONS: These findings suggest that smoking enhances the inflammatory behaviour of DCs and the consequent Th1 and Th17-mediated response in patients with RA.
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Artritis Reumatoide/metabolismo , Proliferación Celular/fisiología , Células Dendríticas/inmunología , Fumar/efectos adversos , Antígenos de Diferenciación de Linfocitos B/inmunología , Artritis Reumatoide/inmunología , Artritis Reumatoide/fisiopatología , Estudios de Casos y Controles , Chile , Progresión de la Enfermedad , Femenino , Citometría de Flujo , Antígenos HLA-DR/inmunología , Humanos , Inflamación/tratamiento farmacológico , Inflamación/fisiopatología , Persona de Mediana Edad , Fenotipo , Fumar/fisiopatología , Subgrupos de Linfocitos T/inmunologíaRESUMEN
Human respiratory syncytial virus (hRSV) is the leading cause of infant hospitalization related to respiratory disease. Infection with hRSV produces abundant infiltration of immune cells into the airways, which combined with an exacerbated pro-inflammatory immune response can lead to significant damage to the lungs. Human RSV re-infection is extremely frequent, suggesting that this virus may have evolved molecular mechanisms that interfere with host adaptive immunity. Infection with hRSV can be reduced by administering a humanized neutralizing antibody against the virus fusion protein in high-risk infants. Although neutralizing antibodies against hRSV effectively block the infection of airway epithelial cells, here we show that both, bone marrow-derived dendritic cells (DCs) and lung DCs undergo infection with IgG-coated virus (hRSV-IC), albeit abortive. Yet, this is enough to negatively modulate DC function. We observed that such a process is mediated by Fcγ receptors (FcγRs) expressed on the surface of DCs. Remarkably, we also observed that in the absence of hRSV-specific antibodies FcγRIII knockout mice displayed significantly less cellular infiltration in the lungs after hRSV infection, compared with wild-type mice, suggesting a potentially harmful, IgG-independent role for this receptor in hRSV disease. Our findings support the notion that FcγRs can contribute significantly to the modulation of DC function by hRSV and hRSV-IC. Further, we provide evidence for an involvement of FcγRIII in the development of hRSV pathogenesis.
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Células Dendríticas/metabolismo , Pulmón/metabolismo , Activación de Linfocitos , Receptores de IgG/metabolismo , Infecciones por Virus Sincitial Respiratorio/metabolismo , Virus Sincitial Respiratorio Humano/patogenicidad , Linfocitos T/metabolismo , Inmunidad Adaptativa , Animales , Anticuerpos Neutralizantes/farmacología , Anticuerpos Antivirales/inmunología , Anticuerpos Antivirales/metabolismo , Antivirales/farmacología , Células Cultivadas , Técnicas de Cocultivo , Citocinas/metabolismo , Células Dendríticas/efectos de los fármacos , Células Dendríticas/inmunología , Células Dendríticas/virología , Modelos Animales de Enfermedad , Inmunoglobulina G/inmunología , Inmunoglobulina G/metabolismo , Pulmón/efectos de los fármacos , Pulmón/inmunología , Pulmón/virología , Activación de Linfocitos/efectos de los fármacos , Ratones Endogámicos C57BL , Ratones Noqueados , Palivizumab/farmacología , Receptores de IgG/deficiencia , Receptores de IgG/genética , Receptores de IgG/inmunología , Infecciones por Virus Sincitial Respiratorio/tratamiento farmacológico , Infecciones por Virus Sincitial Respiratorio/genética , Infecciones por Virus Sincitial Respiratorio/inmunología , Infecciones por Virus Sincitial Respiratorio/virología , Virus Sincitial Respiratorio Humano/efectos de los fármacos , Virus Sincitial Respiratorio Humano/inmunología , Transducción de Señal , Linfocitos T/efectos de los fármacos , Linfocitos T/inmunología , Linfocitos T/virología , Carga Viral , Replicación ViralRESUMEN
APOBEC3G (apolipoprotein B mRNA editing enzyme catalytic polypeptide-like 3G; A3G) is an innate defense protein showing activity against retroviruses and retrotransposons. Activated CD4(+) T cells are highly permissive for HIV-1 replication, whereas resting CD4(+) T cells are refractory. Dendritic cells (DCs), especially mature DCs, are also refractory. We investigated whether these differences could be related to a differential A3G expression and/or subcellular distribution. We found that A3G mRNA and protein expression is very low in resting CD4(+) T cells and immature DCs, but increases strongly following T-cell activation and DC maturation. The Apo-7 anti-A3G monoclonal antibody (mAb), which was specifically developed, confirmed these differences at the protein level and disclosed that A3G is mainly cytoplasmic in resting CD4(+) T cells and immature DCs. Nevertheless, A3G translocates to the nucleus in activated-proliferating CD4(+) T cells, yet remaining cytoplasmic in matured DCs, a finding confirmed by immunoblotting analysis of cytoplasmic and nuclear fractions. Apo-7 mAb was able to immunoprecipitate endogenous A3G allowing to detect complexes with numerous proteins in activated-proliferating but not in resting CD4(+) T cells. The results show for the first time the nuclear translocation of A3G in activated-proliferating CD4(+) T cells.
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Desaminasa APOBEC-3G/metabolismo , Linfocitos T CD4-Positivos/inmunología , Diferenciación Celular , Células Dendríticas/citología , Activación de Linfocitos/inmunología , Desaminasa APOBEC-3G/genética , Desaminasa APOBEC-3G/inmunología , Animales , Anticuerpos Monoclonales/metabolismo , Línea Celular , Núcleo Celular/metabolismo , Humanos , Inmunoprecipitación , Ratones Endogámicos BALB C , Peso Molecular , Monocitos/citología , Unión Proteica , ARN Mensajero/genética , ARN Mensajero/metabolismo , Fracciones Subcelulares/enzimología , Regulación hacia Arriba/genéticaRESUMEN
As it has been established that demethylation of lysine 27 of histone H3 by the lysine-specific demethylase JMJD3 increases immune responses and thus elicits inflammation, we hypothesize that inhibition of JMJD3 may attenuate autoimmune disorders. We found that in vivo administration of GSK-J4, a selective inhibitor of JMJD3 and UTX, ameliorates the severity of experimental autoimmune encephalomyelitis (EAE). In vitro experiments revealed that the anti-inflammatory effect of GSK-J4 was exerted through an effect on dendritic cells (DCs), promoting a tolerogenic profile characterized by reduced expression of costimulatory molecules CD80/CD86, an increased expression of tolerogenic molecules CD103 and TGF-ß1, and reduced secretion of proinflammatory cytokines IL-6, IFN-γ, and TNF. Adoptive transfer of GSK-J4-treated DCs into EAE mice reduced the clinical manifestation of the disease and decreased the extent of inflammatory CD4+ T cells infiltrating the central nervous system. Notably, Treg generation, stability, and suppressive activity were all exacerbated by GSK-J4-treated DCs without affecting Th1 and Th17 cell production. Our data show that GSK-J4-mediated modulation of inflammation is achieved by a direct effect on DCs and that systemic treatment with GSK-J4 or adoptive transfer of GSK-J4-treated DCs ex vivo may be promising approaches for the treatment of inflammatory and autoimmune disorders.
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Benzazepinas/farmacología , Células Dendríticas/efectos de los fármacos , Encefalomielitis Autoinmune Experimental/prevención & control , Histona Demetilasas con Dominio de Jumonji/antagonistas & inhibidores , Pirimidinas/farmacología , Traslado Adoptivo , Animales , Antígenos CD/inmunología , Antígenos CD/metabolismo , Antígeno B7-1/inmunología , Antígeno B7-1/metabolismo , Antígeno B7-2/inmunología , Antígeno B7-2/metabolismo , Western Blotting , Linfocitos T CD4-Positivos/inmunología , Citocinas/genética , Citocinas/inmunología , Citocinas/metabolismo , Células Dendríticas/inmunología , Células Dendríticas/metabolismo , Encefalomielitis Autoinmune Experimental/genética , Encefalomielitis Autoinmune Experimental/inmunología , Expresión Génica/efectos de los fármacos , Tolerancia Inmunológica/genética , Tolerancia Inmunológica/inmunología , Mediadores de Inflamación/inmunología , Mediadores de Inflamación/metabolismo , Cadenas alfa de Integrinas/inmunología , Cadenas alfa de Integrinas/metabolismo , Histona Demetilasas con Dominio de Jumonji/inmunología , Histona Demetilasas con Dominio de Jumonji/metabolismo , Ratones Endogámicos C57BL , Ratones Transgénicos , Fenotipo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Factor de Crecimiento Transformador beta1/inmunología , Factor de Crecimiento Transformador beta1/metabolismoRESUMEN
Emerging evidence has demonstrated that CD4(+) T cells infiltrate into the substantia nigra (SN) in Parkinson's disease (PD) patients and in animal models of PD. SN-infiltrated CD4(+) T cells bearing inflammatory phenotypes promote microglial activation and strongly contribute to neurodegeneration of dopaminergic neurons. Importantly, altered expression of dopamine receptor D3 (D3R) in PBLs from PD patients has been correlated with disease severity. Moreover, pharmacological evidence has suggested that D3R is involved in IFN-γ production by human CD4(+) T cells. In this study, we examined the role of D3R expressed on CD4(+) T cells in neurodegeneration of dopaminergic neurons in the SN using a mouse model of PD. Our results show that D3R-deficient mice are strongly protected against loss of dopaminergic neurons and microglial activation during 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced PD. Notably, D3R-deficient mice become susceptible to MPTP-induced neurodegeneration and microglial activation upon transfer of wild-type (WT) CD4(+) T cells. Furthermore, RAG1 knockout mice, which are devoid of T cells and are resistant to MPTP-induced neurodegeneration, become susceptible to MPTP-induced loss of dopaminergic neurons when reconstituted with WT CD4(+) T cells but not when transferred with D3R-deficient CD4(+) T cells. In agreement, experiments analyzing activation and differentiation of CD4(+) T cells revealed that D3R favors both T cell activation and acquisition of the Th1 inflammatory phenotype. These findings indicate that D3R expressed on CD4(+) T cells plays a fundamental role in the physiopathology of MPTP-induced PD in a mouse model.
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Linfocitos T CD4-Positivos/metabolismo , Neuronas Dopaminérgicas/patología , Proteínas de Homeodominio/genética , Enfermedad de Parkinson/patología , Receptores de Dopamina D3/metabolismo , 1-Metil-4-fenil-1,2,3,6-Tetrahidropiridina , Traslado Adoptivo , Animales , Linfocitos T CD4-Positivos/inmunología , Cuerpo Estriado/metabolismo , Modelos Animales de Enfermedad , Neuronas Dopaminérgicas/inmunología , Inflamación/inmunología , Interferón gamma/biosíntesis , Activación de Linfocitos/inmunología , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Microglía/metabolismo , Degeneración Nerviosa/metabolismo , Enfermedad de Parkinson/metabolismo , Receptores de Dopamina D3/biosíntesis , Receptores de Dopamina D3/genética , Bazo , Sustancia Negra/inmunología , Sustancia Negra/metabolismo , Factor de Necrosis Tumoral alfa/biosíntesisRESUMEN
Dendritic cells (DCs) are responsible for priming T cells and for promoting their differentiation from naive T cells into appropriate effector cells. Emerging evidence suggests that neurotransmitters can modulate T cell-mediated immunity. However, the involvement of specific neurotransmitters or receptors remains poorly understood. In this study, we analyzed the role of dopamine in the regulation of DC function. We found that DCs express dopamine receptors as well as the machinery necessary to synthesize, store, and degrade dopamine. Notably, the expression of D5R decreased upon LPS-induced DC maturation. Deficiency of D5R on the surface of DCs impaired LPS-induced IL-23 and IL-12 production and consequently attenuated the activation and proliferation of Ag-specific CD4(+) T cells. To determine the relevance of D5R expressed on DCs in vivo, we studied the role of this receptor in the modulation of a CD4(+) T cell-driven autoimmunity model. Importantly, D5R-deficient DCs prophylactically transferred into wild-type recipients were able to reduce the severity of experimental autoimmune encephalomyelitis. Furthermore, mice transferred with D5R-deficient DCs displayed a significant reduction in the percentage of Th17 cells infiltrating the CNS without differences in the percentage of Th1 cells compared with animals transferred with wild-type DCs. Our findings demonstrate that by contributing to CD4(+) T cell activation and differentiation to Th17 phenotype, D5R expressed on DCs is able to modulate the development of an autoimmune response in vivo.
Asunto(s)
Células Dendríticas/inmunología , Dopamina/fisiología , Encefalomielitis Autoinmune Experimental/inmunología , Receptores de Dopamina D5/fisiología , Células Th17/inmunología , Traslado Adoptivo , Animales , Comunicación Autocrina/inmunología , Linfocitos T CD4-Positivos/inmunología , Diferenciación Celular , Técnicas de Cocultivo , Citocinas/biosíntesis , Citocinas/genética , Células Dendríticas/efectos de los fármacos , Células Dendríticas/metabolismo , Células Dendríticas/trasplante , Dopamina/metabolismo , Dopamina/farmacología , Encefalomielitis Autoinmune Experimental/terapia , Femenino , Regulación de la Expresión Génica/efectos de los fármacos , Inmunidad Celular , Interleucina-17/biosíntesis , Interleucina-17/genética , Lipopolisacáridos/farmacología , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , ARN Mensajero/biosíntesis , ARN Mensajero/genética , Receptores de Dopamina D5/agonistas , Receptores de Dopamina D5/biosíntesis , Receptores de Dopamina D5/genética , Organismos Libres de Patógenos EspecíficosRESUMEN
Inflammatory bowel diseases (IBD) are a group of chronic inflammatory conditions of the gastrointestinal tract associated with multiple pathogenic factors, including dysregulation of the immune response. Effector CD4+ T cells and regulatory CD4+ T cells (Treg) are central players in maintaining the balance between tolerance and inflammation. Interestingly, genetic modifications in these cells have been implicated in regulating the commitment of specific phenotypes and immune functions. However, the transcriptional program controlling the pathogenic behavior of T helper cells in IBD progression is still unknown. In this study, we aimed to find master transcription regulators controlling the pathogenic behavior of effector CD4+ T cells upon gut inflammation. To achieve this goal, we used an animal model of IBD induced by the transfer of naïve CD4+ T cells into recombination-activating gene 1 (Rag1) deficient mice, which are devoid of lymphocytes. As a control, a group of Rag1-/- mice received the transfer of the whole CD4+ T cells population, which includes both effector T cells and Treg. When gut inflammation progressed, we isolated CD4+ T cells from the colonic lamina propria and spleen tissue, and performed bulk RNA-seq. We identified differentially up- and down-regulated genes by comparing samples from both experimental groups. We found 532 differentially expressed genes (DEGs) in the colon and 30 DEGs in the spleen, mostly related to Th1 response, leukocyte migration, and response to cytokines in lamina propria T-cells. We integrated these data into Gene Regulatory Networks to identify Master Regulators, identifying four up-regulated master gene regulators (Lef1, Dnmt1, Mybl2, and Jup) and only one down-regulated master regulator (Foxo3). The altered expression of master regulators observed in the transcriptomic analysis was confirmed by qRT-PCR analysis and found an up-regulation of Lef1 and Mybl2, but without differences on Dnmt1, Jup, and Foxo3. These two master regulators have been involved in T cells function and cell cycle progression, respectively. We identified two master regulator genes associated with the pathogenic behavior of effector CD4+ T cells in an animal model of IBD. These findings provide two new potential molecular targets for treating IBD.
Asunto(s)
Linfocitos T CD4-Positivos , Redes Reguladoras de Genes , Enfermedades Inflamatorias del Intestino , Animales , Enfermedades Inflamatorias del Intestino/genética , Enfermedades Inflamatorias del Intestino/inmunología , Enfermedades Inflamatorias del Intestino/metabolismo , Enfermedades Inflamatorias del Intestino/patología , Ratones , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD4-Positivos/metabolismo , Modelos Animales de Enfermedad , Linfocitos T Reguladores/inmunología , Linfocitos T Reguladores/metabolismo , Ratones Endogámicos C57BL , Ratones Noqueados , Regulación de la Expresión GénicaRESUMEN
INTRODUCCIÓN: el envejecimiento poblacional es un fenómeno mundial. Los problemas de salud mental, altamente prevalentes en este grupo, impactan en la vida de los individuos, sus familias y la sociedad en su conjunto. OBJETIVO: identificar brechas de conocimiento y prioridades de investigación en salud mental del adulto mayor en Argentina. MATERIAL Y MÉTODOS: diseño cuali-cuantitativo, en tres etapas: (1) diagnóstico de situación, (2) evaluación global de necesidades de investigación y (3) ejercicio de priorización basado en la Matriz de Estrategias Combinadas validada para Argentina (MECA). RESULTADOS: con base en las primeras dos etapas del estudio se identificaron dos áreas temáticas investigar en el país y dimensiones priorizadas: (a) soledad-aislamiento y (b) deterioro cognitivo y demencia. Como resultado del ejercicio de priorización surgieron las siguientes dimensiones: en relación con soledad-aislamiento: 1. efecto de los programas, 2. falta de acceso a los recursos, 3. capacidad de adaptación a los contextos locales (integración social del adulto mayor) y 4. calidad de servicios. En relación con deterioro cognitivo y demencia: 1. impacto cuidadores y entorno, 2. barreras para la implementación de guías y capacitación, 3. estudios de costo-efectividad sobre intervenciones y calidad de vida, y 4. recolección y publicación de datos epidemiológicos. CONCLUSIÓN: se debe enfatizar la importancia de fortalecer la investigación en Argentina sobre la implementación y difusión de intervenciones de promoción, prevención y prestación de servicios en la salud mental del adulto mayor.
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Núcleo Familiar , Humanos , Argentina/epidemiología , Estudios RetrospectivosRESUMEN
Sporothrix brasiliensis is an emerging fungal pathogen causing cat-transmitted sporotrichosis, an epi-zoonosis affecting humans, cats and dogs in Brazil and now spreading to neighboring South American countries. Here, we report the first two autochthonous cases of cat-transmitted sporotrichosis in Paraguay. The first case was a four-year-old male cat showing several ulcerative lesions, nasal deformity and respiratory symptoms. The second case was a one-year-old male cat showing a single ulcerated lesion, respiratory symptoms and nasal deformity. Both cases were admitted to a veterinary clinic in Ciudad del Este, Paraguay. Isolates were recovered from swabs of the two cases. Using molecular methods, the isolates were identified as S. brasiliensis.
RESUMEN
OBJECTIVE: The dopaminergic system plays an important role in the prefrontal cortex (PFC) and is believed to mediate cognitive dysfunction (CD) in bipolar disorder (BD). The enzyme catechol-O-methyltransferase (COMT) is involved in the catabolism of dopamine in the PFC, and an association between COMT single nucleotide polymorphisms (SNPs) and BD has been reported. COMT SNPs have also been associated with executive and working memory performance in healthy subjects, patients with schizophrenia, and euthymic BD patients. The objective of this study was to investigate the association between COMT SNPs and acute CD during BD mood episodes. METHODS: Seventy-two symptomatic, medication-free subjects with bipolar I disorder (BD-I) and 76 healthy controls were evaluated using neuropsychological tests, and genotyped for COMT SNPs rs4680 and rs165599. RESULTS: Patients undergoing mania and mixed episodes carrying the COMT allele G had better performance on executive function, memory, verbal fluency, and intelligence tests. Moreover, an interaction was detected between the COMT allele G and the Young Mania Rating Scale in BD CD. CONCLUSIONS: Allele G from COMT SNPs rs4680 and rs165599 may represent reliable state-dependent predictors of global CD during manic and mixed episodes in BD. Further studies in larger samples are necessary to confirm these findings.
Asunto(s)
Trastorno Bipolar/genética , Catecol O-Metiltransferasa/genética , Trastornos del Conocimiento/genética , Adulto , Alelos , Atención , Trastorno Bipolar/complicaciones , Trastorno Bipolar/metabolismo , Estudios de Casos y Controles , Catecol O-Metiltransferasa/metabolismo , Trastornos del Conocimiento/etiología , Trastornos del Conocimiento/metabolismo , Dopamina/metabolismo , Función Ejecutiva , Femenino , Frecuencia de los Genes , Predisposición Genética a la Enfermedad , Genotipo , Humanos , Pruebas de Inteligencia , Masculino , Memoria , Pruebas Neuropsicológicas , Fenotipo , Polimorfismo de Nucleótido Simple , Corteza Prefrontal/metabolismoRESUMEN
Dopamine has emerged as an important regulator of immunity. Recent evidence has shown that signalling through low-affinity dopamine receptors exerts anti-inflammatory effects, whilst stimulation of high-affinity dopamine receptors potentiates immunity in different models. However, the dopaminergic regulation of CD8+ T-cells in anti-tumour immunity remains poorly explored. Here, we studied the role of dopamine receptor D3 (DRD3), which displays the highest affinity for dopamine, in the function of CD8+ T-cells and its consequences in the anti-tumour immune response. We observed that the deficiency of Drd3 (the gene encoding DRD3) in CD8+ T-cells limits their in vivo expansion, leading to an impaired anti-tumour response in a mouse melanoma model. Mechanistic analyses suggest that DRD3 stimulation favours the production of interleukin 2 (IL-2) and the surface expression of CD25, the α-chain IL-2 receptor, which are required for expansion and effector differentiation of CD8+ T-cells. Thus, our results provide genetic and pharmacologic evidence indicating that DRD3 favours the production of IL-2 by CD8+ T-cells, which is associated with higher expansion and acquisition of effector function of these cells, promoting a more potent anti-tumour response in a melanoma mouse model. These findings contribute to understanding how dopaminergic signalling affects the cellular immune response and represent an opportunity to improve melanoma therapy.
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Melanoma , Linfocitos T Citotóxicos , Animales , Ratones , Linfocitos T CD8-positivos , Modelos Animales de Enfermedad , Dopamina , Interleucina-2/metabolismo , Receptores Dopaminérgicos , Linfocitos T Citotóxicos/metabolismoRESUMEN
Hexavalent chromium [Cr(VI)] is extremely toxic to plant cells and has been recognized to possess a high redox potential. Tolerant plant species have shown the ability to reduce Cr(VI), but the operating mechanism involved in this process is not elucidated. Thus, the aim of this study was to investigate the possible involvement of thiolic and phenolic compounds and thioredoxin expression during Cr(VI) reduction in S. minima. In addition, a probable enzymatic reduction of Cr(VI) was investigated. Plants were exposed to 20 mg L-1 Cr(VI) concentration during 7 days under controlled conditions. The amount of metal accumulated in lacinias (root-like submerged leaves) and fronds (floating leaves) indicated that a low percentage of absorbed Cr(VI) was mobilized from lacinias to fronds. X-ray absorption near-edge structure (XANES) analysis revealed that Cr(III) was the only chromium species occurring in S. minima plants. Thiols and phenolics of lacinias and fronds were increased significantly by Cr(VI) treatment, but accumulation patterns were different. The expression of an h-type thioredoxin (Trx h) was demonstrated for the first time in Cr-exposed lacinias. Enzymatic reduction showed a low contribution to the Cr(VI) reduction. Data of this study provide evidences on the involvement of thiols, thioredoxin, and phenolics in the reduction of Cr(VI) to Cr(III) in S. minima tissues.
Asunto(s)
Cromo , Tracheophyta , Oxidación-Reducción , Fenoles , TiorredoxinasRESUMEN
There is a considerable interindividual variation in L-thyroxine [3,5,3',5'-tetraiodo-l-thyronine (T4)] dose required for thyrotropin (thyroid-stimulating hormone) suppression in patients with differentiated thyroid cancer. To investigate whether uridine diphosphate-glucuronosyl transferase 1A1 (UGT1A1)-mediated T4 glucuronidation in liver affects T4 dose, we genotyped 101 patients for the common UGT1A1-53(TA)n polymorphism and compared T4 doses among patients having zero (5/6 and 6/6 genotypes), one (6/7 genotype), or two (7/7 and 7/8 genotypes) copies of the low-expression (TA)7 and (TA)8 alleles. A significant trend for decreasing T4 dose with increasing number of copies of (TA)7 and (TA)8 (P=0.037) and significant difference in T4 dose across the UGT1A1-53(TA)n genotypes (P=0.048) were observed, despite considerable overlap of T4 doses among different genotypes. These results are consistent with reduced T4 glucuronidation in patients with low-expression (TA)7 and (TA)8 alleles and provide the first evidence for association between UGT1A1-53(TA)n and T4-dose requirement for thyroid-stimulating hormone suppression in a natural clinical setting.
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Diferenciación Celular , Glucuronosiltransferasa/genética , Polimorfismo Genético/genética , Neoplasias de la Tiroides/tratamiento farmacológico , Neoplasias de la Tiroides/genética , Tiroxina/uso terapéutico , Alelos , ADN de Neoplasias/genética , Genotipo , Humanos , Reacción en Cadena de la Polimerasa , Neoplasias de la Tiroides/patología , TirotropinaRESUMEN
The development of various types of cancer results from the interaction among endogenous, environmental and hormonal factors, where the most notable of these factors is diet. The aim of the present study was to determine the antigenotoxic, anticarcinogenic, phagocytic and immunomodulatory activities of Agaricus blazei. The test antigenotoxicity (Comet Assay) and anticarcinogenic (Test of Aberrant Crypt Foci) assess changes in DNA and/or intestinal mucosa that correlate to cancer development. Tests of phagocytosis in the spleen and differential count in blood cells allow the inference of modulation of the immune system as well as to propose a way of eliminating cells with DNA damage. Supplementation with the mushroom was carried out under pre-treatment, simultaneous treatment, post-treatment and pre-treatment+continuous conditions. Statistical analysis demonstrated that the mushroom did not have genotoxic activity but showed antigenotoxic activity. Supplementation caused an increase in the number of monocytes and in phagocytic activity, suggesting that supplementation increases a proliferation of monocytes, consequently increasing phagocytic capacity especially in the groups pre-treatment, simultaneous and pre-treatment+continuous. The data suggest that A. blazei could act as a functional food capable of promoting immunomodulation which can account for the destruction of cells with DNA alterations that correlate with the development of cancer, since this mushroom was demonstrated to have a preventive effect against pre-neoplastic colorectal lesions evaluated by the aberrant crypt foci assay. According to these results and the literature, it is believed that supplementation with A. blazei can be an efficient method for the prevention of cancer as well as possibly being an important coadjuvant treatment in chemotherapy.