RESUMO
Background: The pathogenesis of chronic spontaneous urticaria (CSU) has not been clarified entirely. Type IIb autoimmune chronic spontaneous urticaria (CSUaiTIIb) is a distinct subtype of CSU that is often difficult to treat and is connected to low levels of total IgE. Previous findings indicate that an enhanced signal transducer and activator of transcription 3 (STAT3) may be responsible for reduced IgE serum levels. Objective: Our aim was to investigate a possible underlying gain-of-function mutation or activating polymorphism in STAT3 that could be responsible for the low levels of IgE in patients with CSUaiTIIb. Methods: We included 10 patients with CSUaiTIIb and low levels of IgE and sequenced selected single nucleotide polymorphisms (SNP) in STAT3 associated with common autoimmune diseases. Exon sequencing was performed for the most relevant exons of STAT3. To test for a gain-of-function of STAT3, we performed a phospho-specific flow cytometry analysis of STAT3 in peripheral blood mononuclear cells before and after stimulation with interleukin-6. Results: No differences were found in the prevalence of the tested SNPs between our patients and a control population. Moreover, we could not find any mutations or variants on the tested exons of STAT3. The function of STAT3 was also not altered in our patients. Conclusion: In total, we could not find any evidence for our hypothesis that low IgE in patients with CSUaiTIIb is linked to mutations in STAT3 or altered activity of STAT3. Thus, it remains to be discovered what causes the low serum levels of IgE in patients with CSUaiTIIb.
Assuntos
Urticária Crônica , Imunoglobulina E , Fator de Transcrição STAT3 , Urticária Crônica/sangue , Urticária Crônica/genética , Mutação com Ganho de Função , Humanos , Imunoglobulina E/sangue , Leucócitos Mononucleares , Fator de Transcrição STAT3/sangue , Fator de Transcrição STAT3/genéticaRESUMO
Current genetic characterization of pancreatic ductal adenocarcinoma (PDAC) does not integrate the host reaction to cancer cells and cannot predict the response to chemo- or immunotherapy. The JAK/STAT pathway is an important factor of cytokine-mediated cancer inflammation, but its relationship with pancreatic carcinogenesis and the role of potential biomarkers is not established yet. Our study aimed to assess the significance of serum levels of JAK/STAT3 expression and inflammatory cytokines in PDAC in relation to the clinicopathological features and prognosis. This prospective cohort study included patients with proven adenocarcinoma and a matched group of controls without any malignancies. There were evaluated the serum expression of IL2, 6, 8, 17, JAK2, and STAT3 by ELISA assays in these two groups. The PDAC patients were followed up for 24 months. A Cox regression multivariate analysis model was used to determine factors influencing survival. The study comprised 56 patients with PDAC and 56 controls. The upregulated serum JAK2/STAT3 or cytokines were present in about half of the patients with PDAC, similar to controls. The expression of JAK2 in serum of PDAC patients was significantly associated with the expression of IL2 (p=0.03) and IL6 (p=0.02) but not with survival or metastasis development. Only age and the presence of lymph node metastases were associated with reduced survival in multivariate analyses. The STAT 3/JAK2 expression, although correlated with inflammatory status (IL2, IL6) was not overexpressed in PDAC compared to controls and proved no prognostic value.
Assuntos
Biomarcadores Tumorais/sangue , Carcinoma Ductal Pancreático/sangue , Citocinas/sangue , Janus Quinase 2/sangue , Neoplasias Pancreáticas/sangue , Fator de Transcrição STAT3/sangue , Idoso , Carcinoma Ductal Pancreático/diagnóstico , Carcinoma Ductal Pancreático/terapia , Feminino , Humanos , Mediadores da Inflamação/sangue , Interleucina-2/sangue , Interleucina-6/sangue , Masculino , Pessoa de Meia-Idade , Avaliação de Resultados em Cuidados de Saúde/métodos , Avaliação de Resultados em Cuidados de Saúde/estatística & dados numéricos , Neoplasias Pancreáticas/diagnóstico , Neoplasias Pancreáticas/terapia , Prognóstico , Modelos de Riscos Proporcionais , Estudos Prospectivos , Análise de SobrevidaRESUMO
OBJECTIVES: Preeclampsia is associated with maternal morbidity and mortality during pregnancy, and also an increased cardiovascular disease (CVD) risk later in life. During preeclampsia, alterations in secreted placental factors leading to systemic maternal endothelial dysfunction are evident. However, little is known about the associated endothelial intracellular signaling. STAT3 is a latent cytoplasmic transcription factor involved in endothelial cell differentiation, survival, and angiogenesis. We aimed to test if preeclampsia and preeclampsia-related placental factors could alter serum-induced STAT3(Y705) activation in endothelial cells. Furthermore, if altered serum-induced endothelial STAT3 (Y705) activation is related to post-preeclamptic CVD risk. STUDY DESIGN: HUVECs were used as a model of maternal endothelium. Experiments entailed addition of 20% human pregnancy serum as well as addition of recombinant PlGF, sFLT1 and VEGF-A165a to the cells. MAIN OUTCOME MEASURES: Levels of pSTAT3(Y705) related to STAT3 levels were evaluated by immunoblotting analysis. RESULTS: Our results show that preeclamptic serum induces significantly lower STAT3(Y705) phosphorylation compared with uncomplicated pregnancy serum (P = 0.0089) in endothelial cells. Furthermore, STAT3(Y705) phosphorylation was not changed upon addition of PlGF, sFLT1, or VEGF-A165a together with pregnancy sera compared with sera alone. Finally, sera from women with previous preeclampsia and current hypertension and carotid atherosclerotic plaques show significantly lower STAT3(Y705) phosphorylation capabilities compared with healthy women with previous uncomplicated pregnancies 8-18 years after deliveries (P = 0.029). CONCLUSIONS: Reduction in serum-induced endothelial STAT3(Y705) activation may play an important role in the preeclampsia-associated endothelial dysfunction. Additionally, reduced endothelial STAT3(Y705) phosphorylation may contribute to increased post-preeclamptic CVD risk 8-18 years after delivery.
Assuntos
Placenta/metabolismo , Pré-Eclâmpsia/genética , Fator de Transcrição STAT3/genética , Adulto , Células Endoteliais/metabolismo , Feminino , Humanos , Estudos Longitudinais , Pessoa de Meia-Idade , Pré-Eclâmpsia/sangue , Gravidez , Sistema de Registros , Fatores de Risco , Fator de Transcrição STAT3/sangue , Fator A de Crescimento do Endotélio Vascular/sangueRESUMO
OBJECTIVES: Clinical practice lacks biomarkers to predict the severity of acute pancreatitis (AP). We studied if intracellular signaling of circulating leukocytes could predict persistent organ dysfunction (OD) and secondary infections in AP. METHODS: A venous blood sample was taken from 174 patients with AP 72 hours or less from onset of symptoms and 31 healthy controls. Phosphorylation levels (p) of appropriately stimulated signal transducer and activator of transcription 1 (STAT1), STAT6, nuclear factor-κB (NF-κB), Akt, and nonstimulated STAT3 in monocytes, neutrophils, and lymphocytes was measured using phosphospecific flow cytometry. RESULTS: The patients showed higher pSTAT3 and lower pSTAT1, pSTAT6, pNF-κB, and pAkt than healthy controls. pSTAT3 in all leukocyte subtypes studied increased, and pSTAT1 in monocytes and T cells decreased in an AP severity-wise manner. In patients without OD at sampling, high pSTAT3 in monocytes and T lymphocytes were associated with development of persistent OD. In patients with OD, low interleukin-4-stimulated pSTAT6 in monocytes and neutrophils and Escherichia coli-stimulated pNF-κB in neutrophils predicted OD persistence. High pSTAT3 in monocytes, CD8+ T cells, and neutrophils; low pSTAT1 in monocytes and T cells; and low pNF-κB in lymphocytes predicted secondary infections. CONCLUSIONS: Leukocyte STAT3, STAT1, STAT6, and NF-κΒ phosphorylations are potential predictors of AP severity.
Assuntos
Leucócitos/metabolismo , NF-kappa B/sangue , Pancreatite/sangue , Fatores de Transcrição STAT/sangue , Transdução de Sinais , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/sangue , Estudos de Casos e Controles , Feminino , Citometria de Fluxo , Humanos , Masculino , Pessoa de Meia-Idade , Pancreatite/diagnóstico , Fosforilação , Valor Preditivo dos Testes , Estudos Prospectivos , Fator de Transcrição STAT1/sangue , Fator de Transcrição STAT3/sangue , Fator de Transcrição STAT6/sangue , Índice de Gravidade de Doença , Adulto JovemRESUMO
The aim was to investigate the role of the α7nAChR-mediated cholinergic anti-inflammatory pathway in vagal nerve regulated atrial fibrillation (AF).18 beagles (standard dogs for testing) were used in this study, and the effective refractory period (ERP) of atrium and pulmonary veins and AF inducibility were measured hourly during rapid atrial pacing at 800 beats/minute for 6 hours in all beagles. After cessation of 3 hours of RAP, the low-level vagal nerve stimulation (LL-VNS) group (n = 6) was given LL-VNS and injection of salinne (0.5 mL/GP) into four GPs, the methyllycaconitine (MLA, the antagonist of α7nAChR) group (n = 6) was given LL-VNS and injection of MLA into four GPs, and the Control group (n = 6) was given saline into four GPs and the right cervical vagal nerve was exposed without stimulation. Then, the levels of the tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), acetylcholine (ACh), STAT3, and NF-κB proteins were measured. During the first 3 hours of RAP, the ERPs gradually decreased while the dispersion of ERPs (dERPs) and AF inducibility gradually increased in all three groups. During the last 3 hours of 6 hours' RAP in this study, the ERPs in the LL-VNS group were higher, while the dERPs and AF inducibility were significantly lower when compared with the Control and MLA groups at the same time points. The levels of ACh in the serum and atrium in the LL-VNS and MLA groups were higher than in the Control group, and the levels of TNF-α and IL-6 were higher in the Control and MLA groups than in the LL-VNS group. The concentrations of STAT3 in RA and LA tissues were higher in the LL-VNS group while those of NF-κB were lower.In conclusion, the cholinergic anti-inflammatory pathway mediated by α7nACh plays an important role in low-level vagal nerve-regulated AF.
Assuntos
Aconitina/análogos & derivados , Fibrilação Atrial/fisiopatologia , Neuroimunomodulação/efeitos dos fármacos , Nervo Vago/efeitos dos fármacos , Receptor Nicotínico de Acetilcolina alfa7/antagonistas & inibidores , Acetilcolina/sangue , Aconitina/administração & dosagem , Aconitina/farmacologia , Animais , Estimulação Cardíaca Artificial/efeitos adversos , Estimulação Cardíaca Artificial/métodos , Estudos de Casos e Controles , Modelos Animais de Doenças , Cães , Átrios do Coração/inervação , Átrios do Coração/fisiopatologia , Interleucina-6/sangue , NF-kappa B/sangue , Antagonistas Nicotínicos/administração & dosagem , Antagonistas Nicotínicos/farmacologia , Veias Pulmonares/inervação , Veias Pulmonares/fisiopatologia , Período Refratário Eletrofisiológico/efeitos dos fármacos , Fator de Transcrição STAT3/sangue , Fator de Necrose Tumoral alfa/sangue , Estimulação do Nervo Vago/efeitos adversos , Estimulação do Nervo Vago/métodosRESUMO
Acute pancreatitis (AP) remains a significant clinical challenge. Mitochondrial dysfunction contributes significantly to the pathogenesis of AP. Milk fat globule EGF factor 8 (MFG-E8) is an opsonizing protein, which has many biological functions via binding to αvß3/5 integrins. Ligand-dependent integrin-FAK activation of STAT3 was reported to be of great importance for maintaining a normal mitochondrial function. However, MFG-E8's role in AP has not been evaluated. METHODS: Blood samples were acquired from 69 healthy controls and 134 AP patients. Serum MFG-E8 levels were measured by ELISA. The relationship between serum concentrations of MFG-E8 and disease severity were analyzed. The role of MFG-E8 was evaluated in experimental models of AP. RESULTS: Serum concentrations of MFG-E8 were lower in AP patients than healthy controls. And serum MFG-E8 concentrations were negatively correlated with disease severity in AP patients. In mice, MFG-E8 administration decreased L-arginine-induced pancreatic injury and mortality. MFG-E8's protective effects in experimental AP were associated with improvement in mitochondrial function and reduction in oxidative stress. MFG-E8 knockout mice suffered more severe pancreatic injury and greater mitochondrial damage after l-arginine administration. Mechanistically, MFG-E8 activated the FAK-STAT3 pathway in AP mice. Cilengitide, a specific αvß3/5 integrin inhibitor, abolished MFG-E8's beneficial effects in AP. PF00562271, a specific FAK inhibitor, blocked MFG-E8-induced STAT3 phosphorylation. APTSTAT3-9R, a specific STAT3 antagonist, also eliminated MFG-E8's beneficial effects under such a condition. CONCLUSIONS: MFG-E8 acts as an endogenous protective mediator in the pathogenesis of AP. MFG-E8 administration protects against AP possibly by restoring mitochondrial function via activation of the integrin-FAK-STAT3 signaling pathway. Targeting the action of MFG-E8 may present a potential therapeutic option for AP.
Assuntos
Antígenos de Superfície/sangue , Integrinas/sangue , Proteínas do Leite/sangue , Mitocôndrias/genética , Pancreatite/sangue , Pancreatite/genética , Fator de Transcrição STAT3/sangue , Animais , Antígenos de Superfície/genética , Modelos Animais de Doenças , Feminino , Quinase 1 de Adesão Focal/sangue , Quinase 1 de Adesão Focal/genética , Humanos , Integrinas/genética , Masculino , Camundongos , Pessoa de Meia-Idade , Proteínas do Leite/genética , Fator de Transcrição STAT3/genética , Transdução de Sinais/genéticaRESUMO
Background: Although gliomas are confined to the central nervous system, their negative influence over the immune system extends to peripheral circulation. The immune suppression exerted by myeloid cells can affect both response to therapy and disease outcome. We analyzed the expansion of several myeloid parameters in the blood of low- and high-grade gliomas and assessed their relevance as biomarkers of disease and clinical outcome. Methods: Peripheral blood was obtained from 134 low- and high-grade glioma patients. CD14+, CD14+/p-STAT3+, CD14+/PD-L1+, CD15+ cells and four myeloid-derived suppressor cell (MDSC) subsets, were evaluated by flow cytometry. Arginase-1 (ARG1) quantity and activity was determined in the plasma. Multivariable logistic regression model was used to obtain a diagnostic score to discriminate glioma patients from healthy controls and between each glioma grade. A glioblastoma prognostic model was determined by multiple Cox regression using clinical and myeloid parameters. Results: Changes in myeloid parameters associated with immune suppression allowed to define a diagnostic score calculating the risk of being a glioma patient. The same parameters, together with age, permit to calculate the risk score in differentiating each glioma grade. A prognostic model for glioblastoma patients stemmed out from a Cox multiple analysis, highlighting the role of MDSC, p-STAT3, and ARG1 activity together with clinical parameters in predicting patient's outcome. Conclusions: This work emphasizes the role of systemic immune suppression carried out by myeloid cells in gliomas. The identification of biomarkers associated with immune landscape, diagnosis, and outcome of glioblastoma patients lays the ground for their clinical use.
Assuntos
Biomarcadores Tumorais/sangue , Glioma/sangue , Glioma/diagnóstico , Células Mieloides/imunologia , Células Mieloides/metabolismo , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Arginase/sangue , Antígeno B7-H1/sangue , Feminino , Glioma/etiologia , Humanos , Hospedeiro Imunocomprometido , Imunofenotipagem , Leucócitos Mononucleares/imunologia , Leucócitos Mononucleares/metabolismo , Biópsia Líquida , Masculino , Pessoa de Meia-Idade , Células Supressoras Mieloides/imunologia , Células Supressoras Mieloides/metabolismo , Gradação de Tumores , Estadiamento de Neoplasias , Prognóstico , Fator de Transcrição STAT3/sangue , Adulto JovemRESUMO
Guchang Zhixie Wan (GZW) is a commonly used Chinese medicine for the treatment of ulcerative colitis (UC). This research explored the potential pharmacological mechanism of GZW in UC. The active ingredients, potential targets, and UC-related genes of GZW were retrieved from public databases. The pharmacological mechanisms including key components, potential targets and signal pathways were determined through bioinformatics analysis. The results of this study were verified through virtual molecular docking and cell experiments. Network analysis revealed that 26 active GZW compounds and 148 potential GZW target proteins were associated with UC. Quercetin, kaempferol and ß-sitosterol were identified as the core active ingredients of GZW. IFNG, IL-1A, IL-1B, JUN, RELA, and STAT1 were indicated as key targets of GZW. These key targets have a strong affinity for quercetin, kaempferol, and ß-sitosterol. GO and KEGG enrichment analysis showed that GZW target proteins are highly enriched in inflammatory, immune, and oxidative stress-related pathways. This study confirmed the therapeutic effect and revealed potential molecular mechanism of GZW on UC. And the protective effects of GZW on inflammatory bowel disease pathway were also revealed through STAT3/NF-κB/IL-6 pathway. The findings of this study enhanced our understanding of GZW in the treatment of UC and provided a feasible method for discovering potential drugs from traditional Chinese medicine formulations.
Assuntos
Medicamentos de Ervas Chinesas/metabolismo , Animais , Sítios de Ligação , Colite Ulcerativa/tratamento farmacológico , Colite Ulcerativa/patologia , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/farmacologia , Medicamentos de Ervas Chinesas/uso terapêutico , Humanos , Interleucina-6/sangue , Interleucina-6/metabolismo , Medicina Tradicional Chinesa , Camundongos , Simulação de Acoplamento Molecular , Mapas de Interação de Proteínas , Células RAW 264.7 , Fator de Transcrição STAT3/sangue , Fator de Transcrição STAT3/metabolismo , Transdução de Sinais/efeitos dos fármacos , Fator de Transcrição RelA/sangue , Fator de Transcrição RelA/metabolismoRESUMO
Chronic hepatitis B (CHB) is a life-threatening disease caused by HBV infection. Our previous work proved that activation of ERK1/2 and STAT3 signaling was involved in HBV tolerance. We herein investigated clinical significances of serum ERK1/2 and STAT3 proteins in CHB. Results showed that ERK1/2 and STAT3 were fluctuated with natural history of CHB. In addition, STAT3 was found to be positively correlated to the elevation of ALT, AST and GGT, while ERK1 was negatively correlated to decreases of TP and ALB. Also, there was a positive correlation between the anti-HBc antibody and ERK1, ERK2 or STAT3 in HBeAg-negative patients. Strikingly, serum ERK1 and ERK2 could reflect level of HBsAg-specific CD8+ T cells. A model composed with baseline ERK1 and ERK2 levels had a high accuracy to predict the effect of IFNα treatment. In conclusion, serum ERK1, ERK2 and STAT3 could serve as novel biomarkers in chronic HBV infections.
Assuntos
Linfócitos T CD8-Positivos/imunologia , Hepatite B Crônica , Interferon-alfa/uso terapêutico , Proteína Quinase 1 Ativada por Mitógeno/sangue , Proteína Quinase 3 Ativada por Mitógeno/sangue , Anticorpos Anti-Hepatite B/sangue , Hepatite B Crônica/sangue , Hepatite B Crônica/tratamento farmacológico , Hepatite B Crônica/imunologia , Humanos , Proteína Quinase 1 Ativada por Mitógeno/imunologia , Proteína Quinase 3 Ativada por Mitógeno/imunologia , Fator de Transcrição STAT3/sangue , Fator de Transcrição STAT3/imunologia , Resultado do TratamentoRESUMO
Metabolic syndrome (MetS) is a low-grade inflammation state that results from an interplay between genetic and environmental factors. The incidence of MetS among individuals with insulin resistance, dyslipidemia, elevated blood pressure, and obesity, which constitute the syndrome, is 40% in the Middle East. The absence of an approved therapeutic agent for MetS is one reason to investigate tocilizumab (TCZ), which might be effective in the treatment of MetS. Results have implicated interleukin 6 (IL-6) in the development of MetS, identifying inflammation as a critical factor in its etiology and offering hope for new therapeutic approaches development. Here, we evaluate whether tocilizumab can be used for metabolic syndrome treatment. We assigned rats to three groups, 8 rats each: a negative-control group, provided with standard rodent chow and water; a fructose-fed group, provided with standard rodent chow and 10% fructose in drinking water for 22 weeks; and a treatment group, fed as per the metabolic syndrome group but treated with tocilizumab (5 mg/kg/week, intraperitoneal) for the final 5 weeks. Treatment with TCZ successfully ameliorated the damaging effects of fructose by stabilizing body weight gain and through the normalization of serum biochemical parameters and histopathological examination. Significant differences in adipokine levels were perceived, resulting in a significant decline in serum leptin and interleukin 6 (IL-6) levels concurrent with adiponectin normalization. Tocilizumab might be an effective agent for the treatment of metabolic syndrome. However, further investigations on human subjects are needed before the clinical application of tocilizumab for this indication.
Assuntos
Adipocinas/sangue , Anticorpos Monoclonais Humanizados/uso terapêutico , Frutose/toxicidade , Interleucina-6/sangue , Síndrome Metabólica/sangue , Fator de Transcrição STAT3/sangue , Animais , Anticorpos Monoclonais Humanizados/farmacologia , Resistência à Insulina/fisiologia , Masculino , Síndrome Metabólica/induzido quimicamente , Síndrome Metabólica/prevenção & controle , Ratos , Ratos WistarRESUMO
OBJECTIVES: To elucidate the molecular mechanisms underlying pathogenic Th17 cells, we investigated the modulation of epigenetic modifications and its association with SLE. METHODS: Naive CD4+ T cells were cultured in Th17 polarizing conditions for 5 days and then treated with various cytokines, including IL-23. Expression of Th17 cell-related markers and phosphorylation of signal transducers and activators of transcription (pSTATs) were analysed using flow cytometry and quantitative PCR. Histone modifications were assessed using chromatin immunoprecipitation PCR. T cell phenotypes and pSTATs were analysed in blood samples of patients with SLE (n = 28). Finally, the effects of baricitinib on memory Th17 cells were investigated in SLE patients (n = 12). RESULTS: Stimulation of resting Th17 cells with IL-23 promoted maturation of these cells (P < 0.0001). IL-23 induced pSTAT3, but not pSTAT4, during Th17 cell maturation (P < 0.05). IL-23-induced STAT3 directly bound the RORγT gene locus. This was accompanied by induction of the H3H4me3 permissive mark and reduction of the H3K27me3 repressive mark, leading to enhanced RORγT gene expression. IL-23-induced expansion of Th17 cells and pSTAT3 were suppressed by the addition of baricitinib in a concentration-dependent manner (P < 0.05). In memory Th17 cells from SLE patients, pSTAT3 was hypersensitized by IL-23 stimulation and inhibited by baricitinib (P < 0.05). CONCLUSION: The results of this study indicate that IL-23/STAT3 signalling plays a fundamental role in Th17 cell maturation through transcriptional and epigenetic modifications in patients with SLE. This mechanism may underlie pathogenic Th17 cell expansion and may lead to identification of novel therapeutic targets for SLE.
Assuntos
Interleucina-23/farmacologia , Lúpus Eritematoso Sistêmico/sangue , Fator de Transcrição STAT3/sangue , Células Th17/efeitos dos fármacos , Azetidinas/farmacologia , Linfócitos T CD4-Positivos/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Imunoprecipitação da Cromatina/métodos , Epigênese Genética , Citometria de Fluxo , Expressão Gênica , Humanos , Interleucina-12/farmacologia , Interleucinas/farmacologia , Histona Desmetilases com o Domínio Jumonji/metabolismo , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/genética , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/metabolismo , Fosforilação , Purinas/farmacologia , Pirazóis/farmacologia , Reação em Cadeia da Polimerase em Tempo Real/métodos , Fator de Transcrição STAT3/efeitos dos fármacos , Fator de Transcrição STAT3/metabolismo , Fator de Transcrição STAT4/metabolismo , Transdução de Sinais , Sulfonamidas/farmacologia , Células Th17/metabolismoRESUMO
BACKGROUND AND OBJECTIVES: IgA nephropathy is the most common primary glomerular disease in the world. Marked by mesangial inflammation and proliferation, it generally leads to progressive kidney fibrosis. As the Janus kinase signal transducer and activator of transcription pathway has been implicated as an important mediator of diabetic kidney disease and FSGS, detailed investigation of this pathway in IgA nephropathy was undertaken to establish the basis for targeting this pathway across glomerular diseases. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: Well characterized patients with IgA nephropathy and controls were studied, allowing us to compare 77 patients with biopsy-proven IgA nephropathy with 45 healthy subjects. STAT phosphorylation was assessed in peripheral blood monocytes (PBMCs) by phosphoflow before and after cytokine stimulation. Kidney Janus kinase signal transducer and activator of transcription activity was studied by immunofluorescence and by transcriptomic studies. An STAT1 activity score was established using downstream transcriptional targets of pSTAT1 and associated with disease and clinical outcomes. RESULTS: We found PBMCs to have upregulated pSTAT production at baseline in patients with IgA nephropathy with a limited reserve to respond to cytokine stimulation compared with controls. Increased staining in glomerular mesangium and endothelium was seen for Jak-2 and pSTAT1 and in the tubulointerstitial for JAK2, pSTAT1, and pSTAT3. Activation of the Janus kinase signal transducer and activator of transcription pathway was further supported by increased pSTAT1 and pSTAT3 scores in glomerular and tubulointerstitial sections of the kidney (glomerular activation Z scores: 7.1 and 4.5, respectively; P values: <0.001 and <0.001, respectively). Clinically, phosphoflow results associated with proteinuria and kidney function, and STAT1 activation associated with proteinuria but was not associated with progression. CONCLUSIONS: Janus kinase signal transducer and activator of transcription signaling was activated in patients with IgA nephropathy compared with controls. There were altered responses in peripheral immune cells and increased message and activated proteins in the kidney. These changes variably related to proteinuria and kidney function.
Assuntos
Glomerulonefrite por IGA/genética , Glomerulonefrite por IGA/metabolismo , Janus Quinase 2/metabolismo , Fator de Transcrição STAT1/metabolismo , Fator de Transcrição STAT3/metabolismo , Adulto , Linfócitos T CD4-Positivos/metabolismo , Estudos de Casos e Controles , Endotélio/metabolismo , Feminino , Perfilação da Expressão Gênica , Mesângio Glomerular/metabolismo , Glomerulonefrite por IGA/sangue , Glomerulonefrite por IGA/patologia , Humanos , Interferon gama/genética , Janus Quinase 1/genética , Janus Quinase 2/sangue , Túbulos Renais/metabolismo , Masculino , Pessoa de Meia-Idade , Monócitos/metabolismo , Fosforilação , Fator de Transcrição STAT1/sangue , Fator de Transcrição STAT1/genética , Fator de Transcrição STAT3/sangue , Transdução de Sinais/genética , Adulto JovemRESUMO
STAT3 plays an important role in regulating gene expression and is closely related with cancer. Thus, the sensitive and specific detection of the STAT3 biomarker is of great importance for disease diagnosis and therapeutics. In this study, by combining the target recycling amplification (TRA) with strand displacement amplification (SDA), we have developed a label-free and highly sensitive method for the dual-amplified detection of STAT3. The assay system consists of polymerization primer and label-free hairpin probe (HP) containing palindromic fragment and nicking site. In the presence of STAT3, the stem of the HP is opened, followed by the primer binding to initiate TRA and SDA with the help of Klenow Fragment (KF) and nickase. After multiple replication, nicking, and strand displacement, STAT3 was released and initiated the next round of reactions, generating a large number of terminal palindrome-contained fragments. Subsequently, the intermolecular hybridization between palindromic fragments occurred and the bidirectional extension by polymerase takes place, forming the dsDNAs. The double-stranded DNA products can be quantified by measuring the fluorescence intensity of SYBR Green I. The proposed strategy shows the excellent specificity and high sensitivity with a detection limit as low as 50 pM. In addition, this designed protocol can be successfully applied to detect the STAT3 in human serum, indicating great potential for the practical application in early diagnosis and prognosis.
Assuntos
Biomarcadores Tumorais/genética , Técnicas Biossensoriais , Técnicas de Amplificação de Ácido Nucleico , Fator de Transcrição STAT3/genética , Biomarcadores Tumorais/sangue , DNA de Neoplasias/genética , Humanos , Tamanho da Partícula , Fator de Transcrição STAT3/sangue , Propriedades de SuperfícieAssuntos
Receptores de Lipopolissacarídeos/imunologia , Monócitos/metabolismo , Fator de Transcrição STAT3/sangue , Escleroderma Sistêmico/sangue , Adulto , Biomarcadores/sangue , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Monócitos/imunologia , Fosforilação/imunologia , Fator de Transcrição STAT3/imunologia , Escleroderma Sistêmico/imunologiaRESUMO
Autism spectrum disorder (ASD) is a heterogeneous syndrome characterized by dysregulations in speech and social interactions as well as repetitive and stereotypical behavioral patterns in which immune system plays a significant role. IL-6, an essential cytokine for polarization of Th0 cells into Th17 cells has been demonstrated to be crucial in the etiology of ASD in past studies both in humans and mice. Th17 cells are also believed to be central players in the pathogenesis of ASD through release of IL-17A. However, there is still insufficient data regarding identification of Th17 cells with respect to IL-6 signaling in ASD subjects. Therefore, this study explored IL-6 receptors (IL-6R/sIL-6R) and Th17 (p-STAT3/IL-17A/IL-23R) related markers comprehensively in the blood of typically-developing control (TDC, nâ¯=â¯35) and ASD children (nâ¯=â¯45). Our data show that there is enhanced sIL-6R levels in plasma and CD4+ T cells of ASD subjects as compared to TDC group. Increased sIL-6R signaling is associated with upregulated Th17 development in ASD subjects. Further, severe ASD subjects have higher inflammation in terms of IL-6/IL-17A related signaling as compared to moderate ASD patients. Furthermore, treatment of CD4â¯+â¯T cells in vitro with IL-6 leads to much greater upregulation of p-STAT3, and IL-17A in ASD subjects than similarly treated CD4+ T cells in TDC group. Antagonism of IL-6 signaling by SC144 in vitro led to blockade of IL-6 mediated effects on CD4+ T cells. These data display unequivocally that IL-6 signaling components are dysregulated which play a crucial in enhancement of Th17 development in ASD subjects.
Assuntos
Transtorno do Espectro Autista/imunologia , Linfócitos T CD4-Positivos/metabolismo , Interleucina-17/sangue , Receptores de Interleucina-6/sangue , Receptores de Interleucina/sangue , Fator de Transcrição STAT3/sangue , Células Th17/imunologia , Transtorno do Espectro Autista/sangue , Estudos de Casos e Controles , Criança , Estudos Transversais , Feminino , Humanos , Interleucina-6/metabolismo , Masculino , Índice de Gravidade de Doença , Regulação para CimaRESUMO
BACKGROUND: Prenatal alcohol exposure (PAE) causes long-term growth and neurodevelopmental deficits that are worsened by maternal iron deficiency (ID). In our preclinical rat model, PAE causes fetal anemia, brain ID, and elevated hepatic iron via increased maternal and fetal hepcidin synthesis. These changes are normalized by a prenatal iron-fortified (IF) diet. Here, we hypothesize that iron status and PAE dysregulate the major upstream pathways that govern hepcidin production-EPO/BMP6/SMAD and IL-6/JAK2/STAT3. METHODS: Pregnant, Long Evans rat dams consumed ID (2 to 6 ppm iron), iron-sufficient (IS, 100 ppm iron), or IF (500 ppm iron) diets and received alcohol (5 g/kg) or isocaloric maltodextrin daily from gestational days (GD) 13.5 to 19.5. Protein and gene expression were quantified in the 6 experimental groups at GD 20.5. RESULTS: PAE did not affect Epo or Bmp6 expression, but reduced p-SMAD1/5/8/SMAD1/5/8 protein ratios in both IS and ID maternal and fetal liver (all p's < 0.01). In contrast, PAE stimulated maternal hepatic expression of Il-6 (p = 0.03) and elevated p-STAT3/STAT3 protein ratios in both IS and ID maternal and fetal liver (all p's < 0.02). PAE modestly elevated maternal Il-1ß, Tnf-α, and Ifn-γ. Fetal cytokine responses to PAE were muted compared with dams, and PAE did not affect hepatic Il-6 (p = 0.78) in IS and ID fetuses. Dietary iron fortification sharply attenuated Il-6 expression in response to PAE, with IF driving a 150-fold decrease (p < 0.001) in maternal liver and a 10-fold decrease (p < 0.01) in fetal liver. The IF diet also normalized p-STAT3/STAT3 ratios in both maternal and fetal liver. CONCLUSIONS: These findings suggest that alcohol-driven stimulation of the IL-6/JAK2/STAT3 pathway mediates the elevated hepcidin observed in the PAE dam and fetus. Normalization of these signals by IF suggests that dysregulated hepcidin is driven by alcohol's disruption of the IL-6/JAK2/STAT3 pathway. Prenatal dietary IF represents a potential therapeutic approach for PAE that warrants further investigation.
Assuntos
Anemia Ferropriva/complicações , Etanol/efeitos adversos , Feto/efeitos dos fármacos , Interleucina-6/sangue , Efeitos Tardios da Exposição Pré-Natal/sangue , Fator de Transcrição STAT3/sangue , Animais , Modelos Animais de Doenças , Feminino , Feto/metabolismo , Interleucina-6/metabolismo , Ferro da Dieta , Gravidez , Ratos , Ratos Long-Evans , Reação em Cadeia da Polimerase em Tempo Real , Fator de Transcrição STAT3/metabolismo , Transdução de Sinais/efeitos dos fármacosRESUMO
OBJECTIVE AND DESIGN: The purpose of this study was to investigate the roles of SMYD3 and STAT3 in chronic lymphocytic leukemia (CLL) and the possible underlying mechanisms. MATERIALS: Blood samples were collected from 20 patients with CLL and 20 hematologically normal donors. Human cell lines K562, HL-60, MEG-1, and BALL-1 were performed in vitro and BALB/c nude mouse was used in subcutaneous tumor experiments. TREATMENT: WP1066 (30 mg/kg) was also injected intratumorally two days after the first lentivirus treatment and then every four days for a total of four injections and 3 µM WP1066 was carried out for 48 h to downregulate STAT3 phosphorylation. METHODS: We performed studies using the human CLL cell line MEG-1 in vitro and nude mouse subcutaneous tumor experiments in vivo. Differential expression of RNAs was determined using qRT-PCR. The CCK-8 assay and colony formation assay were conducted to evaluate cell proliferation. Flow cytometry was performed to assess cell apoptosis. The relative protein levels were detected using western blotting. Chromatin immunoprecipitation (ChIP) assays, luciferase reporter assays and WP1066, a STAT3 inhibitor, were used to explore the regulatory mechanisms of proteases and transcription factors. A subcutaneous tumor model was constructed to verify the results in vivo. RESULTS: SMYD3 and STAT3 expressions positively correlated with the progression of CLL. Upregulation of SMYD3 significantly promoted the proliferation and inhibited the expression of apoptosis-related genes. The results of the ChIP assays and luciferase reporter assays suggested that STAT3 targeted the promoter region of SMYD3 and, thus, promoted SMYD3 transcription. Downregulation of the phosphorylation of STAT3 by WP1066 notably inhibited the binding of STAT3 to the SMYD3 promoter, and subsequently downregulated SMYD3 transcription. The STAT3 inhibitor inhibited CLL cell growth in vivo, and overexpression of SMYD3 promoted CLL cell growth. Furthermore, overexpression of SMYD3 reversed the inhibitory effects of the STAT3 inhibitor on CLL cell growth. CONCLUSIONS: The STAT3-mediated transcription of SMYD3 plays a role in promoting the progression of chronic lymphocytic leukemia.
Assuntos
Regulação Leucêmica da Expressão Gênica , Histona-Lisina N-Metiltransferase/metabolismo , Leucemia Linfocítica Crônica de Células B/metabolismo , Fator de Transcrição STAT3/metabolismo , Animais , Apoptose , Células HL-60 , Histona-Lisina N-Metiltransferase/sangue , Humanos , Células K562 , Leucemia Linfocítica Crônica de Células B/sangue , Camundongos , Camundongos Nus , Transplante de Neoplasias , Fosforilação , Ligação Proteica , Piridinas/farmacologia , Fator de Transcrição STAT3/sangue , Tirfostinas/farmacologiaRESUMO
Background and objectives: Gastric cancer (GC) is one of the deadliest malignancies, with the underlying pathophysiological mechanisms still not completely understood. In this study, we aimed to investigate the signal transducer and activator of transcription 3 (STAT3) moleculeconnection with the pathological features of GCs, and the expression of cell adhesive molecules (E-cadherin and ß-catenin) and angiogenesis-related factors (vascular endothelial growth factor (VEGF), HIF1α, and CD31)). Materials and Methods: This study comprised 136 cases of GCs with data related to the patients' demographic characteristics (age, gender) and pathological features (tumor location, gross type, Laurens' type of GC, histological differentiation, invasion depth, lymphovascular invasion and the presence of metastases) which were correlated with STAT3 expression. Additionally, STAT3 expression and the expression of adhesive molecules and angiogenesis-related factors were studied by immunohistochemical methods. Results: The expression of STAT3 was found to be significantly associated with the occurrence of poorly differentiated GCs in the lower portion of the stomach and with the presence of distant metastases. Interestingly, none of the investigated parameters related to cell adhesion or to angiogenesis were found to be related to the expression of STAT3. Conclusions: The lack of significant differences between the studied STAT3 expression and some of the molecules associated with different cancer features might be due to the characteristics of the studied population sample associated with the origin, heterogeneity, and cancer pathophysiological background. Nonetheless, the results of our study suggest that STAT3 could be a useful marker for the presence of distant GC metastases, which further indicates that STAT3 action might involve some other signaling molecules/pathways that warrant further elucidation.
Assuntos
Prognóstico , Fator de Transcrição STAT3/análise , Neoplasias Gástricas/patologia , Adulto , Idoso , Indutores da Angiogênese , Adesão Celular/fisiologia , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Pessoa de Meia-Idade , Fator de Transcrição STAT3/sangue , Transdução de SinaisRESUMO
OBJECTIVE: Clinical and laboratory studies have demonstrated that platelets become hyperactive and prothrombotic in conditions of inflammation. We have previously shown that the proinflammatory cytokine interleukin (IL)-6 forms a complex with soluble IL-6 receptor α (sIL-6Rα) to prime platelets for activation by subthreshold concentrations of collagen. Upon being stimulated with collagen, the transcription factor signal transducer and activator of transcription (STAT) 3 in platelets is phosphorylated and dimerized to act as a protein scaffold to facilitate the catalytic action between the kinase Syk and the substrate phospholipase Cγ2 (PLCγ2) in collagen-induced signaling. However, it remains unknown how collagen induces phosphorylation and dimerization of STAT3. METHODS AND RESULTS: We conducted complementary in vitro experiments to show that the IL-6 receptor subunit glycoprotein 130 (GP130) was in physical proximity to the collagen receptor glycoprotein VI (GPVI in membrane lipid rafts of platelets. This proximity allows collagen to induce STAT3 activation and dimerization, and the IL-6-sIL-6Rα complex to activate the kinase Syk and the substrate PLCγ2 in the GPVI signal pathway, resulting in an enhanced platelet response to collagen. Disrupting lipid rafts or blocking GP130-Janus tyrosine kinase (JAK)-STAT3 signaling abolished the cross-activation and reduced platelet reactivity to collagen. CONCLUSION: These results demonstrate cross-talk between collagen and IL-6 signal pathways. This cross-talk could potentially provide a novel mechanism for inflammation-induced platelet hyperactivity, so the IL-6-GP130-JAK-STAT3 pathway has been identified as a potential target to block this hyperactivity.
Assuntos
Plaquetas/metabolismo , Receptor gp130 de Citocina/sangue , Microdomínios da Membrana/fisiologia , Glicoproteínas da Membrana de Plaquetas/fisiologia , Coagulação Sanguínea/efeitos dos fármacos , Colágeno/farmacologia , Receptor gp130 de Citocina/química , Hemorreologia , Humanos , Imunoprecipitação , Janus Quinase 2/antagonistas & inibidores , Janus Quinase 2/sangue , Fosfolipase C gama/sangue , Fosforilação , Agregação Plaquetária/efeitos dos fármacos , Agregação Plaquetária/fisiologia , Glicoproteínas da Membrana de Plaquetas/química , Mapeamento de Interação de Proteínas , Inibidores de Proteínas Quinases/farmacologia , Processamento de Proteína Pós-Traducional , Fator de Transcrição STAT3/sangueRESUMO
miRNAs are noncoding RNAs representing an important class of gene expression modulators. Extracellular circulating miRNAs are both candidate biomarkers for disease pathogenesis and mediators of cell-to-cell communication. We examined the miRNA expression profile of total serum and serum-derived exosome-enriched extracellular vesicles in people with normal glucose tolerance or type 2 diabetes. In contrast to total serum miRNA, which did not reveal any differences in miRNA expression, we identified differentially abundant miRNAs in patients with type 2 diabetes using miRNA expression profiles of exosome RNA (exoRNA). To validate the role of these differentially abundant miRNAs on glucose metabolism, we transfected miR-20b-5p, a highly abundant exoRNA in patients with type 2 diabetes, into primary human skeletal muscle cells. miR-20b-5p overexpression increased basal glycogen synthesis in human skeletal muscle cells. We identified AKTIP and STAT3 as miR-20b-5p targets. miR-20b-5p overexpression reduced AKTIP abundance and insulin-stimulated glycogen accumulation. In conclusion, exosome-derived extracellular miR-20b-5p is a circulating biomarker associated with type 2 diabetes that plays an intracellular role in modulating insulin-stimulated glucose metabolism via AKT signaling.