RESUMO
BACKGROUND/AIM: The nocturnal production of melatonin by the pineal gland is triggered by sympathetic activation of adrenoceptors and may be modulated by immunological signals. The effect of glucocorticoids on nocturnal melatonin synthesis is controversial; both stimulatory and inhibitory effects have been reported. During pathophysiological processes, an increased sympathetic tonus could result in different patterns of adrenoceptor activation in the pineal gland. Therefore, in this investigation, we evaluated whether the pattern of adrenergic stimulation of the pineal gland drives the direction of the glucocorticoid effect on melatonin production. METHODS: The corticosterone effect on the pineal hormonal production induced by ß-adrenoceptor or ß+α1-adrenoceptor activation was evaluated in cultured glands. We also investigated whether the in vivo lipopolysaccharide (LPS)-induced inhibition of melatonin is dependent on the interaction of glucocorticoids and the α1-adrenoceptor in adrenalectomized animals and on the in vivo blockade of glucocorticoid receptors (GRs) or the α1-adrenoceptor. RESULTS: Corticosterone potentiated ß-adrenoceptor-induced pineal melatonin synthesis, whilst corticosterone-dependent inhibition was observed when melatonin production was induced by ß+α1-adrenoceptors agonists. The inhibitory effect of corticosterone is mediated by GR, as it was abolished in the presence of a GR antagonist. Moreover, LPS-induced reduction in melatonin nocturnal plasma content was reversed by adrenalectomy and by antagonizing GR or α1-adrenoceptors. CONCLUSIONS: The dual effect of corticosterone on pineal melatonin synthesis is determined by the activation pattern of adrenoceptors (ß or ß+α1) in the gland during GR activation, suggesting that increased activation of the sympathetic system and the hypothalamic-pituitary-adrenal axis are necessary for the control of melatonin production during defense responses.
Assuntos
Catecolaminas/metabolismo , Corticosterona/administração & dosagem , Melatonina/biossíntese , Glândula Pineal/metabolismo , Receptores Adrenérgicos alfa 1/metabolismo , Receptores Adrenérgicos beta/metabolismo , Agonistas Adrenérgicos beta/administração & dosagem , Animais , Inflamação/metabolismo , Isoproterenol/administração & dosagem , Lipopolissacarídeos , Masculino , Glândula Pineal/efeitos dos fármacos , Ratos , Ratos WistarRESUMO
The phenotype of primary cells in culture varies according to the donor environmental condition. We recently showed that the time of the day imposes a molecular program linked to the inflammatory response that is heritable in culture. Here we investigated whether microRNAs (miRNAs) would show differential expression according to the time when cells were obtained, namely daytime or nighttime. Cells obtained from explants of cremaster muscle and cultivated until confluence (â¼20 days) presented high CD133 expression. Global miRNA expression analysis was performed through deep sequencing in order to compare both cultured cells. A total of 504 mature miRNAs were identified, with a specific miRNA signature being associated to the light versus dark phase of a circadian cycle. miR-1249 and miR-129-2-3p were highly expressed in daytime cells, while miR-182, miR-96-5p, miR-146a-3p, miR-146a-5p, and miR-223-3p were highly expressed in nighttime cells. Nighttime cells are regulated for programs involved in cell processes and development, as well as in the inflammation, cell differentiation and maturation; while daytime cells express miRNAs that control stemness and cytoskeleton remodeling. In summary, the time of the day imposes a differential profile regarding to miRNA signature on CD133(+) cells in culture. Understanding this daily profile in the phenotype of cultured cells is highly relevant for clinical outputs, including cellular therapy approaches. J. Cell. Physiol. 231: 1953-1963, 2016. © 2016 Wiley Periodicals, Inc.
Assuntos
Diferenciação Celular/genética , Inflamação/genética , MicroRNAs/genética , Fotoperíodo , Antígeno AC133/imunologia , Animais , Células Cultivadas , Perfilação da Expressão Gênica/métodos , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Masculino , Ratos WistarRESUMO
Melatonin is the hormone produced by the pineal gland known to regulate physiologic rhythms and to display immunomodulatory and neuroprotective properties. It has been reported that Alzheimer disease patients show impaired melatonin production and altered expression of the 2 G protein-coupled melatonin receptors (MTRs), MT1 and MT2, but the underlying mechanisms are not known. Here we evaluated whether this dysfunction of the melatonergic system is directly caused by amyloid ß peptides (Aß(1-40) and Aß(1-42)). Aß treatment of rat pineal glands elicited an inflammatory response within the gland, evidenced by the up-regulation of 52 inflammatory genes, and decreased the production of melatonin up to 75% compared to vehicle-treated glands. Blocking NF-κB activity prevented this effect. Exposure of HEK293 cells stably expressing recombinant MT1 or MT2 receptors to Aß lead to a 40% reduction in [(125)I]iodomelatonin binding to MT1. ERK1/2 activation triggered by MTRs, but not by the ß2-adrenergic receptor, was markedly impaired by Aß in HEK293 transfected cells, as well as in primary rat endothelial cells expressing endogenous MTRs. Our data reveal the melatonergic system as a new target of Aß, opening new perspectives to Alzheimer disease diagnosis and therapeutic intervention.
Assuntos
Peptídeos beta-Amiloides/farmacologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Melatonina/biossíntese , Fragmentos de Peptídeos/farmacologia , Glândula Pineal/efeitos dos fármacos , Receptores de Melatonina/metabolismo , Animais , Células Cultivadas , Citocinas/genética , Citocinas/metabolismo , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/metabolismo , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Expressão Gênica/efeitos dos fármacos , Células HEK293 , Humanos , Immunoblotting , Masculino , Glândula Pineal/metabolismo , Multimerização Proteica/efeitos dos fármacos , Ratos Wistar , Receptores de Melatonina/química , Receptores de Melatonina/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução de Sinais/efeitos dos fármacos , Técnicas de Cultura de TecidosRESUMO
The endothelial layer regulates the traffic of cells and substances between the blood and tissues and plays a central role in the mounting of an inflammatory response. We have recently shown that inhibition of the nocturnal melatonin surge during the mounting of an inflammatory response primes endothelial cells to a highly reactive state, increasing the expression of adhesion molecules and inducible nitric oxide synthase (iNOS) as well as the in vitro adherence of leukocytes. Here, we investigated whether physiological variations in the plasma melatonin levels owing to the light/dark environmental cycle could also prime the reactive state of endothelial cells. Cultured endothelial cells (16-20 days) obtained from rats killed during the daytime adhere more neutrophils, expressed more adhesion molecules and iNOS, and had a higher content of the transcription factor nuclear factor kappa B (NF-kB) translocated to the nuclei. We also evaluated the expression of 84 genes (using real-time PCR array) related to the innate inflammatory response and observed a higher expression of 19 genes in cultures obtained during the daytime. In addition, the only gene that was highly expressed in cells obtained from rats killed during nighttime was one that encodes a protein that negatively modulates inflammatory response. In conclusion, the daily rhythm of melatonin also primes the ability of endothelial cells to adhere to neutrophils. This new approach for evaluating the influence of the donor on cells maintained in culture should have applications for the standardization of cell banks.
Assuntos
Células Endoteliais/metabolismo , Iluminação , Melatonina/metabolismo , Óxido Nítrico Sintase Tipo II/metabolismo , Animais , Ensaio de Desvio de Mobilidade Eletroforética , Imunofluorescência , Masculino , NF-kappa B/metabolismo , Neutrófilos/metabolismo , RatosRESUMO
Primary central nervous system (CNS) tumors are the most common deadly childhood cancer. Several patients with medulloblastoma experience local or metastatic recurrences after standard treatment, a condition associated with very poor prognosis. Current neuroimaging techniques do not accurately detect residual stem-like medulloblastoma cells promoting tumor relapses. In attempt to identify candidate tumor markers that could be circulating in blood or cerebrospinal (CSF) fluid of patients, we evaluated the proteome and miRNome content of extracellular microvesicles (MVs) released by highly-aggressive stem-like medulloblastoma cells overexpressing the pluripotent factor OCT4A. These cells display enhanced tumor initiating capability and resistance to chemotherapeutic agents. A common set of 464 proteins and 10 microRNAs were exclusively detected in MVs of OCT4A-overexpressing cells from four distinct medulloblastoma cell lines, DAOY, CHLA-01-MED, D283-MED, and USP13-MED. The interactome mapping of these exclusive proteins and miRNAs revealed ERK, PI3K/AKT/mTOR, EGF/EGFR, and stem cell self-renewal as the main oncogenic signaling pathways altered in these aggressive medulloblastoma cells. Of these MV cargos, four proteins (UBE2M, HNRNPCL2, HNRNPCL3, HNRNPCL4) and five miRNAs (miR-4449, miR-500b, miR-3648, miR-1291, miR-3607) have not been previously reported in MVs from normal tissues and in CSF. These proteins and miRNAs carried within MVs might serve as biomarkers of aggressive stem-like medulloblastoma cells to improve clinical benefit by helping refining diagnosis, patient stratification, and early detection of relapsed disease.
Assuntos
Neoplasias Cerebelares/diagnóstico , Vesículas Extracelulares/metabolismo , Meduloblastoma/diagnóstico , MicroRNAs/análise , Proteoma/análise , Biomarcadores Tumorais/sangue , Biomarcadores Tumorais/líquido cefalorraquidiano , Linhagem Celular Tumoral , Neoplasias Cerebelares/sangue , Neoplasias Cerebelares/líquido cefalorraquidiano , Humanos , Meduloblastoma/sangue , Meduloblastoma/líquido cefalorraquidiano , Prognóstico , ProteômicaRESUMO
Inflammatory joint conditions are characterized by synovial inflammation, which involves activation of fibroblast-like synoviocytes (FLSs) and production of inflammatory mediators and matrix metalloproteases (MMPs) in joints. This study showed that the snake venom metalloprotease (SVMP) BaP1 activates FLSs to produce PGE2 by a mechanism dependent on COX-2, mPGES-1 and iPLA2s. BaP1 also induces IL-1ß release, which up-regulates the production of PGE2 at a late stage of the stimulation. Expression of COX-2 and mPGES-1 are induced by BaP1 via activation of NF-κB pathway. While NF-κB p50 and p65 subunits are involved in up-regulation of COX-2 expression, only p65 is involved in BaP1-induced mPGES-1 expression. In addition, BaP1 up-regulates EP4 receptor expression. Engagement of this receptor by PGE2 triggers a positive feedback loop for its production by up-regulating expression of key components of the PGE2 biosynthetic cascade (COX-2, mPGES-1 and the EP4 receptor), thus contributing to amplification of BaP1-induced effects in FLSs. These data highlight the importance of FLS as a target for metalloproteases in joint inflammation and provide new insights into the roles of MMPs in inflammatory joint diseases. Moreover, our results may give insights into the importance of the catalytic domain, of MMPs for the inflammatory activity of these enzymes.
Assuntos
Dinoprostona/metabolismo , Fibroblastos/metabolismo , Interleucina-1beta/metabolismo , Metaloendopeptidases/farmacologia , Receptores de Prostaglandina E Subtipo EP4/metabolismo , Transdução de Sinais , Animais , Ciclo-Oxigenase 2/metabolismo , Regulação da Expressão Gênica , Inflamação , Masculino , NF-kappa B/metabolismo , Ratos , Ratos Wistar , Doenças Reumáticas/metabolismo , Líquido Sinovial/citologia , Regulação para CimaRESUMO
Melatonin is well known for its circadian production by the pineal gland, and there is a growing body of data showing that it is also produced by many other cells and organs, including immune cells. The chronobiotic role of pineal melatonin, as well as its protective effects in vitro and in vivo, have been extensively explored. However, the interaction between the chronobiotic and defence functions of endogenous melatonin has been little investigated. This review details the current knowledge regarding the coordinated shift in melatonin synthesis from the pineal gland (circadian and monitoring roles) to the regulation of acute immune responses via immune cell production and autocrine effects, producing systemic interactions termed the immune-pineal axis. An acute inflammatory response drives the transcription factor, NFκB, to switch melatonin synthesis from pinealocytes to macrophages/microglia and, upon acute inflammatory resolution, back to pinealocytes. The potential pathophysiological relevance of immune-pineal axis dysregulation is highlighted, with both research and clinical implications, across several medical conditions, including host/parasite interaction, neurodegenerative diseases and cancer. LINKED ARTICLES: This article is part of a themed section on Recent Developments in Research of Melatonin and its Potential Therapeutic Applications. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v175.16/issuetoc.
Assuntos
Melatonina/imunologia , Fagócitos/imunologia , Glândula Pineal/imunologia , Animais , Humanos , Imunidade Inata , Inflamação/imunologia , Neoplasias/metabolismoRESUMO
Objetivo: Estimar a custo-efetividade do blinatumomabe como novo padrão no tratamento de consolidação de pacientes pediátricos com leucemia linfoblástica aguda de células precursoras B (LLA-B) em primeira recidiva de alto risco. Métodos: Um modelo de sobrevida particionado com horizonte lifetime e ciclo de quatro semanas foi construído na perspectiva do Sistema Único de Saúde (SUS). Sobrevida livre de eventos e sobrevida global foram extrapoladas com base no ensaio clínico 20120215, usando funções paramétricas. A taxa de desconto foi de 5%. O impacto de variações em pressupostos foi explorado em análises de cenário. Resultados: O custo lifetime com desconto para o caso base foi de R$ 351.615 para blinatumomabe contra R$ 97.770 para HC3 (grupo controle de quimioterapia-padrão), com ganho de 9,96 e 6,74 anos de vida ajustados para qualidade (QALYs), respectivamente. A razão de custo-efetividade incremental (RCEI) foi de R$ 78.873/QALY. Considerando um cenário sem descontos, a RCEI foi de R$ 33.731/QALY ganho. Os outros cenários com maior impacto na RCEI foram a exclusão do desperdício de blinatumomabe (isto é, considerando que a sobra em frasco-ampola de um paciente seria reaproveitada para outro paciente: R$ 35.751) e a alteração do tempo de infusão (troca de bolsa em 48 ou 96 horas em vez de 24 horas: R$ 35.515). A probabilidade de o blinatumomabe ser custo-efetivo foi de 65,7% na análise probabilística, considerando um limiar de R$ 95.501. Conclusões: Blinatumomabe é custo-efetivo para pacientes pediátricos com LLA-B derivada em primeira recidiva de alto risco na perspectiva do SUS.
Objective: To estimate the cost-effectiveness of blinatumomab as the new standard treatment of consolidation in high-risk first relapse pediatric patients with B-cell acute lymphoblastic leukemia (B-ALL). Methods: A partitioned survival model with a lifetime horizon and a 4-week cycle was developed from the Brazilian public healthcare payer's perspective (SUS). Event-free survival and overall survival were extrapolated based on data from the 20120215 clinical trial using parametric functions. A 5% discount rate was used, and the impact of variations in model parameters and assumptions were explored in scenario analyses. Results: The discounted base case lifetime cost was R$ 351,615 for blinatumomab vs. R$ 97,770 for standard chemotherapy control group (HC3), with 9.96 QALYs gained with blinatumomab vs. 6.74 QALYs gained with HC3. The incremental costeffectiveness ratio (ICER) was R$ 78,873/QALY. Considering an undiscounted scenario, the ICER was.
Assuntos
Sistema Único de Saúde , Leucemia-Linfoma Linfoblástico de Células Precursoras , Análise de Custo-EfetividadeRESUMO
Tumors develop numerous strategies to fine-tune inflammation and avoid detection and eradication by the immune system. The identification of mechanisms leading to local immune dysregulation is critical to improve cancer therapy. We here demonstrate that Interleukin-1 receptor 8 (IL-1R8 - previously known as SIGIRR/TIR8), a negative regulator of Toll-Like and Interleukin-1 Receptor family signaling, is up-regulated during breast epithelial cell transformation and in primary breast tumors. IL-1R8 expression in transformed breast epithelial cells reduced IL-1-dependent NF-κB activation and production of pro-inflammatory cytokines, inhibited NK cell activation and favored M2-like macrophage polarization. In a murine breast cancer model (MMTV-neu), IL-1R8-deficiency reduced tumor growth and metastasis and was associated with increased mobilization and activation of immune cells, such as NK cells and CD8+ T cells. Finally, immune-gene signature analysis in clinical specimens revealed that high IL-1R8 expression is associated with impaired innate immune sensing and T-cell exclusion from the tumor microenvironment. Our results indicate that high IL-1R8 expression acts as a novel immunomodulatory mechanism leading to dysregulated immunity with important implications for breast cancer immunotherapy.
Assuntos
Neoplasias da Mama/genética , Neoplasias da Mama/imunologia , Regulação Neoplásica da Expressão Gênica , Imunidade/genética , Receptores de Interleucina-1/genética , Animais , Neoplasias da Mama/patologia , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Linhagem Celular Tumoral , Transformação Celular Neoplásica/genética , Transformação Celular Neoplásica/imunologia , Citocinas/metabolismo , Células Dendríticas/imunologia , Células Dendríticas/metabolismo , Modelos Animais de Doenças , Feminino , Perfilação da Expressão Gênica , Humanos , Imunidade Inata/genética , Imunomodulação , Mediadores da Inflamação/metabolismo , Células Matadoras Naturais/imunologia , Células Matadoras Naturais/metabolismo , Camundongos , Camundongos Knockout , NF-kappa B/metabolismo , Evasão Tumoral/genéticaRESUMO
Until 15 years ago, vasculogenesis, the formation of new blood vessels from undifferentiated cells, was thought to occur only during embryonic development. The discovery of circulating cells that are able to promote vascular regeneration and repair-the so-called endothelial progenitor cells (EPCs)-changed that, and EPCs have since been studied extensively. It is already known that EPCs include many subtypes of cells that play a variety of roles in promoting vascular growth. Some EPCs are destined to differentiate into endothelial cells, whereas others are capable of promoting and sustaining angiogenesis through paracrine mechanisms. Vasculogenesis and angiogenesis might constitute complementary mechanisms for postnatal neovascularization, and EPCs could be at the core of this process. Although the formation of new blood vessels from preexisting vasculature plays a beneficial role in many physiological processes, such as wound healing, it also contributes to tumor growth and metastasis. However, many aspects of the role played by EPCs in tumor angiogenesis remain unclear. This review aims to address the main aspects of EPCs differentiation and certain characteristics of their main function, especially in tumor angiogenesis, as well as the potential clinical applications.
RESUMO
BACKGROUND: Endothelial cells are of great interest for cell therapy and tissue engineering. Understanding the heterogeneity among cell lines originating from different sources and culture protocols may allow more standardized material to be obtained. In a recent paper, we showed that adrenalectomy interferes with the expression of membrane adhesion molecules on endothelial cells maintained in culture for 16 to 18 days. In addition, the pineal hormone, melatonin, reduces the adhesion of neutrophils to post-capillary veins in rats. Here, we evaluated whether the reactivity of cultured endothelial cells maintained for more than two weeks in culture is inversely correlated to plasma melatonin concentration. METHODOLOGY/PRINCIPAL FINDINGS: The nocturnal levels of melatonin were manipulated by treating rats with LPS. Nocturnal plasma melatonin, significantly reduced two hours after LPS treatment, returned to control levels after six hours. Endothelial cells obtained from animals that had lower nocturnal melatonin levels significantly express enhanced adhesion molecules and iNOS, and have more leukocytes adhered than cells from animals that had normal nocturnal levels of melatonin (naïve or injected with vehicle). Endothelial cells from animals sacrificed two hours after a simultaneous injection of LPS and melatonin present similar phenotype and function than those obtained from control animals. Analyzing together all the data, taking into account the plasma melatonin concentration versus the expression of adhesion molecules or iNOS we detected a significant inverse correlation. CONCLUSIONS/SIGNIFICANCE: Our data strongly suggest that the plasma melatonin level primes endothelial cells "in vivo," indicating that the state of the donor animal is translated to cells in culture and therefore, should be considered for establishing cell banks in ideal conditions.