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The removal of dead cells (efferocytosis) contributes to the resolution of the infection and preservation of the tissue. Depending on the environment milieu, macrophages may show inflammatory (M1) or anti-inflammatory (M2) phenotypes. Inflammatory leukocytes are recruited during infection, followed by the accumulation of infected and non-infected apoptotic cells (AC). Efferocytosis of non-infected AC promotes TGF-ß, IL-10, and PGE2 production and the polarization of anti-inflammatory macrophages. These M2 macrophages acquire an efficient ability to remove apoptotic cells that are involved in tissue repair and resolution of inflammation. On the other hand, the impact of efferocytosis of infected apoptotic cells on macrophage activation profile remains unknown. Here, we are showing that the efferocytosis of gram-positive Streptococcus pneumoniae-AC (Sp-AC) or gram-negative Klebsiella pneumoniae-AC (Kp-AC) promotes distinct gene expression and cytokine signature in macrophages. Whereas the efferocytosis of Kp-AC triggered a predominant M1 phenotype in vitro and in vivo, the efferocytosis of Sp-AC promoted a mixed M1/M2 activation in vitro and in vivo in a model of allergic asthma. Together, these findings suggest that the nature of the pathogen and antigen load into AC may have different impacts on inducing macrophage polarization.
Assuntos
Apoptose , Fagocitose , Macrófagos/metabolismo , Fenótipo , Anti-InflamatóriosRESUMO
Inflammatory responses are terminated by the clearance of dead cells, a process termed efferocytosis. A consequence of efferocytosis is the synthesis of the antiinflammatory mediators TGF-ß, PGE2, and IL-10; however, the efferocytosis of infected cells favors Th17 responses by eliciting the synthesis of TGF-ß, IL-6, and IL-23. Recently, we showed that the efferocytosis of apoptotic Escherichia coli-infected macrophages by dendritic cells triggers PGE2 production in addition to pro-Th17 cytokine expression. We therefore examined the role of PGE2 during Th17 differentiation and intestinal pathology. The efferocytosis of apoptotic E. coli-infected cells by dendritic cells promoted high levels of PGE2, which impaired IL-1R expression via the EP4-PKA pathway in T cells and consequently inhibited Th17 differentiation. The outcome of murine intestinal Citrobacter rodentium infection was dependent on the EP4 receptor. Infected mice treated with EP4 antagonist showed enhanced intestinal defense against C. rodentium compared with infected mice treated with vehicle control. Those results suggest that EP4 signaling during infectious colitis could be targeted as a way to enhance Th17 immunity and host defense.
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Citrobacter rodentium/imunologia , Colite/imunologia , Células Dendríticas/imunologia , Dinoprostona/imunologia , Infecções por Enterobacteriaceae/imunologia , Intestinos/imunologia , Macrófagos/imunologia , Animais , Colite/microbiologia , Colite/patologia , Células Dendríticas/microbiologia , Células Dendríticas/patologia , Infecções por Enterobacteriaceae/microbiologia , Infecções por Enterobacteriaceae/patologia , Feminino , Intestinos/microbiologia , Macrófagos/microbiologia , Macrófagos/patologia , Camundongos , Receptores de Prostaglandina E Subtipo EP4/imunologiaRESUMO
Efferocytosis, or clearance of apoptotic cells (ACs), by dendritic cells (DCs) leads to immune response suppression and tolerance to self-antigens. However, efferocytosis of infected apoptotic cells (IACs) leads to the production of a mixed pro- and anti-inflammatory cytokine milieu. We examined the DC phenotype and ability to migrate after phagocytosis of ACs or IACs and observed higher levels of CD86 and CCR7 expression in DCs, as well as enhanced migration capacity following efferocytosis of IACs. Interestingly, higher levels of interleukin-1ß, interleukin-10 and prostaglandin E2 (PGE2 ) were also produced in this context. Blockage of IAC recognition led to an impaired maturation profile and PGE2 production, which may have contributed to reduced CD86 and CCR7 expression and migration capacity. These data contribute to the understanding of how efferocytosis of sterile or infected cells may regulate the adaptive immune response, although the precise role of PGE2 in this process requires further investigation.
Assuntos
Apoptose , Quimiotaxia , Células Dendríticas/patologia , Infecções por Escherichia coli/patologia , Linfonodos/patologia , Macrófagos/patologia , Fagocitose , Animais , Antígeno B7-2/metabolismo , Quimiocina CCL19/metabolismo , Quimiocina CCL21/metabolismo , Técnicas de Cocultura , Células Dendríticas/imunologia , Células Dendríticas/metabolismo , Células Dendríticas/microbiologia , Dinoprostona/metabolismo , Infecções por Escherichia coli/imunologia , Infecções por Escherichia coli/metabolismo , Infecções por Escherichia coli/microbiologia , Feminino , Mediadores da Inflamação/metabolismo , Linfonodos/imunologia , Linfonodos/metabolismo , Macrófagos/imunologia , Macrófagos/metabolismo , Macrófagos/microbiologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Fenótipo , Células RAW 264.7 , Receptores CCR7/metabolismo , Transdução de SinaisRESUMO
Background and objective: Imprinted genes are important for the offspring development. To assess the relationship between obesity-related H19DMR methylation and H19 and IGF2 gene expression and offspring growth and body composition. Methods: Thirty-nine overweight/obese and 25 normal weight pregnant women were selected from the "Araraquara Cohort Study" according to their pre-pregnancy BMI. Fetal growth and body composition and newborn growth were assessed, respectively, by ultrasound and anthropometry. The methylation of H19DMR in maternal blood, cord blood, maternal decidua and placental villi tissues was evaluated by methylation-sensitive restriction endonuclease qPCR, and H19 and IGF2 expression by relative real-time PCR quantification. Multiple linear regression models explored the associations of DNA methylation and gene expression with maternal, fetal, and newborn parameters. Results: H19DMR was less methylated in maternal blood of the overweight/obese group. There were associations of H19DMR methylation in cord blood with centiles of fetal biparietal diameter (BPD) and abdominal subcutaneous fat thickness and newborn head circumference (HC); H19DMR methylation in maternal decidua with fetal occipitofrontal diameter (OFD), HC, and length; H19DMR methylation in placental villi with fetal OFD, HC and abdominal subcutaneous fat thickness and with newborn HC. H19 expression in maternal decidua was associated with fetal BPD and femur length centiles and in placental villi with fetal OFD and subcutaneous arm fat. IGF2 expression in maternal decidua was associated with fetal BPD and in placental villi with fetal OFD. Conclusion: To our knowledge, this is the first study to demonstrate associations of imprinted genes variations at the maternal-fetal interface of the placenta and in cord blood with fetal body composition, supporting the involvement of epigenetic mechanisms in offspring growth and body composition.
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OBJECTIVE: To investigate associations of maternal and cord blood cytokine patterns with newborn size and body composition. METHODS: This cross-sectional study involved 70 pregnant women and their healthy newborns selected from the "Araraquara Cohort Study". Newborn anthropometric measurements were recorded at birth. Body composition was evaluated by air displacement plethysmography. Maternal blood samples were collected from pregnant women between 30 and 36 weeks of gestation, and umbilical cord blood samples were collected immediately after placenta discharge. The concentrations of the cytokines were determined in plasma by ELISA. Multiple linear regression models were used to assess associations between maternal and cord blood cytokine concentrations and newborn anthropometry and body composition measurements. RESULTS: Maternal plasma TGF-ß1 concentration was inversely associated with newborn weight (ß = -43.0; p = 0.012), length (ß = -0.16, p = 0.028), head circumference (ß = -0.13, p = 0.004), ponderal index (ß = -0.32, p = 0.011) and fat-free mass (ß = -0.05, p = 0.005). However, the association persisted just for head circumference (ß = -0.26; p = 0.030) and ponderal index (ß = - 0.28; p = 0.028), after adjusting for pre-gestational BMI, gestational weight gain, gestational age, hours after delivery, newborn sex, smoking and alcohol consumption. CONCLUSIONS: Maternal plasma TGF-ß1 concentration may be involved in the regulation of newborn size, mainly head circumference and ponderal index. Further cohort studies are necessary to investigate the role of TGF-ß1 in different trimesters of pregnancy and its effect during the early stages of fetal development.
Assuntos
Desenvolvimento Fetal , Fator de Crescimento Transformador beta1 , Humanos , Recém-Nascido , Gravidez , Feminino , Estudos de Coortes , Peso ao Nascer , Estudos Transversais , Idade GestacionalRESUMO
Obesity is increasing in incidence worldwide, especially in women, which can affect the outcome of pregnancy. During this period, viral infections represent a risk to the mother, the placental unit, and the fetus. The Zika virus (ZIKV) outbreak in Brazil has been the cause of congenital Zika syndrome (CZS), with devastating consequences such as microcephaly in newborns. Herein, we analyzed the impact of maternal overweight/obesity on the antiviral factors' expression in the placental tissue of Zika-infected mothers. We accessed placentas from women with and without obesity from 34 public health units (São Paulo) and from Zika-infected mothers with and without obesity from the Clinical Cohort Study of ZIKV pregnant women (Rio de Janeiro, Brazil). We first verified that obesity, without infection, did not alter the constitutive transcriptional expression of antiviral factors or IFN type I/III expression. Interestingly, obesity, when associated with ZIKV infection, showed a decreased transcriptional expression of RIG-I and IFIH1 (MDA-5 protein precursor gene). At the protein level, we also verified a decreased RIG-I and IRF-3 expression in the decidual placenta from the Zika-infected obese group, regardless of microcephaly. This finding shows, for the first time, that obesity associated with ZIKV infection leads to an impaired type I IFN downstream signaling pathway in the maternal-fetal interface.
Assuntos
Interferon Tipo I , Microcefalia , Infecção por Zika virus , Zika virus , Recém-Nascido , Gravidez , Feminino , Humanos , Antivirais , Gestantes , Infecção por Zika virus/complicações , Estudos de Coortes , Brasil/epidemiologia , Placenta , ObesidadeRESUMO
Apoptotic cell clearance by professional and nonprofessional phagocytes in the process of efferocytosis is critical to preserve tissue homeostasis. Uptake of apoptotic cells by dendritic cells generates regulatory T cells and induces immunologic tolerance against self-antigens. In contrast, ingestion of infected apoptotic cells promotes activation of TLR4/MyD88-dependent bone marrow-derived dendritic cells (BMDCs) and triggers Th17 cell differentiation. In this study, we evaluated the impact of Streptococcus pneumoniae-infected apoptotic cell efferocytosis by BMDCs derived from C57BL/6 mice on differentiation and expansion of CD4+ T cell subsets, as well as the role of TLR2/4 and receptor-interacting protein 2 (RIP2) receptors in recognizing intracellular pathogens during efferocytosis. We demonstrated that BMDC-mediated efferocytosis of S. pneumoniae-infected apoptotic cells induced Th1 cell differentiation and expansion. Although TLR2/4 and RIP2 deficiency in BMDCs did not affect Th1 cell differentiation during efferocytosis, the absence of RIP2 decreased IFN-γ production by CD4 T cells during the expansion phase. These findings suggest that RIP2-mediated IL-1ß production during efferocytosis of S. pneumoniae-infected apoptotic cells partially supports a Th1-mediated IFN-γ production microenvironment.
Assuntos
Linfócitos T CD4-Positivos , Interferon gama/biossíntese , Streptococcus pneumoniae , Receptor 2 Toll-Like , Ubiquitina-Proteína Ligases/metabolismo , Animais , Apoptose , Interferon gama/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Transdução de Sinais , Células Th1 , Receptor 2 Toll-Like/metabolismoRESUMO
In 2019, COVID-19 emerged as a severe respiratory disease that is caused by the novel coronavirus, Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2). The disease has been associated with high mortality rate, especially in patients with comorbidities such as diabetes, cardiovascular and kidney diseases. This could be attributed to dysregulated immune responses and severe systemic inflammation in COVID-19 patients. The use of effective antiviral drugs against SARS-CoV-2 and modulation of the immune responses could be a potential therapeutic strategy for COVID-19. Studies have shown that natural phenolic compounds have several pharmacological properties, including anticoronavirus and immunomodulatory activities. Therefore, this review discusses the dual action of these natural products from the perspective of applicability at COVID-19.
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Antivirais/uso terapêutico , Tratamento Farmacológico da COVID-19 , Flavonoides/uso terapêutico , Fatores Imunológicos/uso terapêutico , Compostos Fitoquímicos/uso terapêutico , Inibidores de Proteases/uso terapêutico , Animais , Antivirais/química , Antivirais/farmacologia , Coronavirus/efeitos dos fármacos , Flavonoides/química , Flavonoides/farmacologia , Humanos , Fatores Imunológicos/química , Fatores Imunológicos/farmacologia , Compostos Fitoquímicos/química , Compostos Fitoquímicos/farmacologia , Inibidores de Proteases/química , Inibidores de Proteases/farmacologiaRESUMO
Bioactive compounds found in food and medicinal plants contribute to maintaining health and treating illnesses. For example, hydroxycinnamic acids, such as ferulic acid, are widely present in nature and have several pharmacological properties, including antioxidant, anti-inflammatory, and beneficial effects in parameters of diabetes and hyperlipidemia. The results of studies in animal models and in vitro experiments of ferulic acid suggest its high therapeutic and preventive potential against several pathological disorders, such as cardiovascular diseases. Therefore, in this review, the bioactivities of ferulic acid on the cardiovascular system are described, including the discussion of the mechanisms of action in the various components of the system. In this review, we discuss the pharmacological properties of this versatile natural product in aspects of cardiovascular health, including cardioprotective and antihypertensive actions, and on the metabolism of lipids, diabetes, and thrombosis.
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Doenças Cardiovasculares/prevenção & controle , Ácidos Cumáricos/uso terapêutico , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Antioxidantes/química , Produtos Biológicos/farmacologia , Produtos Biológicos/uso terapêutico , Doenças Cardiovasculares/metabolismo , Doenças Cardiovasculares/patologia , Ácidos Cumáricos/química , Ácidos Cumáricos/farmacologia , Microbioma Gastrointestinal/efeitos dos fármacos , Humanos , Estresse Oxidativo/efeitos dos fármacos , Trombose/tratamento farmacológico , Vasodilatação/efeitos dos fármacosRESUMO
Background: The efficiency of isolation and purification of the viral genome is a critical step to the accuracy and reliability of RT-qPCR to detect SARS-CoV-2. However, COVID-19 testing laboratories were overwhelmed by a surge in diagnostic demand that affected supply chains especially in low and middle-income facilities. Objectives: Thus, this study compares the performance of alternative methods to extraction and purification of viral RNA in samples of patients diagnosed with COVID-19. Study design: Nasopharyngeal swabs were submitted to three in-house protocols and three commercial methods; viral genome was detected using the primer-probe (N1 and N2) described by CDC and viral load of samples were determined. Results: The in-house protocols resulted in detection of virus in 82.4 to 86.3% of samples and commercial methods in 94.1 to 98%. The disagreement results were observed in samples with low viral load or below the estimated limit of detection of RT-qPCR. Conclusion: The simplified methods proposed might be less reliable for patients with low viral load and alternative commercial methods showed comparable performance.
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Abstract Objective To investigate associations of maternal and cord blood cytokine patterns with newborn size and body composition. Methods This cross-sectional study involved 70 pregnant women and their healthy newborns selected from the "Araraquara Cohort Study". Newborn anthropometric measurements were recorded at birth. Body composition was evaluated by air displacement plethysmography. Maternal blood samples were collected from pregnant women between 30 and 36 weeks of gestation, and umbilical cord blood samples were collected immediately after placenta discharge. The concentrations of the cytokines were determined in plasma by ELISA. Multiple linear regression models were used to assess associations between maternal and cord blood cytokine concentrations and newborn anthropometry and body composition measurements. Results Maternal plasma TGF-β1 concentration was inversely associated with newborn weight (β= -43.0; p= 0.012), length (β= -0.16, p= 0.028), head circumference (β= -0.13, p= 0.004), ponderal index (β= -0.32, p= 0.011) and fat-free mass (β= -0.05, p= 0.005). However, the association persisted just for head circumference (β= -0.26; p= 0.030) and ponderal index (β= - 0.28; p= 0.028), after adjusting for pre-gestational BMI, gestational weight gain, gestational age, hours after delivery, newborn sex, smoking and alcohol consumption. Conclusions Maternal plasma TGF-β1 concentration may be involved in the regulation of newborn size, mainly head circumference and ponderal index. Further cohort studies are necessary to investigate the role of TGF-β1 in different trimesters of pregnancy and its effect during the early stages of fetal development.
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BACKGROUND: Some probiotic strains have the potential to assist in relieving the symptoms of inflammatory bowel disease. The impact of daily ingestion of a soy-based product fermented by Enterococcus faecium CRL 183 and Lactobacillus helveticus 416 with the addition of Bifidobacterium longum ATCC 15707 on chemically induced colitis has been investigated thereof within a period of 30 days. METHODS: Colitis was induced by dextran sulfate sodium. The animals were randomly assigned into five groups: Group C: negative control; Group CL: positive control; Group CLF: DSS with the fermented product; Group CLP: DSS with the non-fermented product (placebo); Group CLS: DSS with sulfasalazine. The following parameters were monitored: disease activity index, fecal microbial analyses, gastrointestinal survival of probiotic microorganisms and short-chain fatty acids concentration in the feces. At the end of the protocol the animals' colons were removed so as to conduct a macroscopical and histopathological analysis, cytokines and nitrite quantification. RESULTS: Animals belonging to the CLF group showed fewer symptoms of colitis during the induction period and a lower degree of inflammation and ulceration in their colon compared to the CL, CLS and CLP groups (p<0.05). The colon of the animals in groups CL and CLS presented severe crypt damage, which was absent in CLF and CLP groups. A significant increase in the population of Lactobacillus spp. and Bifidobacterium spp. at the end of the protocol was verified only in the CLF animals (p<0.05). This group also showed an increase in short-chain fatty acids (propionate and acetate). Furthermore, the intestinal survival of E. faecium CRL 183 and B. longum ATCC 15707 in the CLF group has been confirmed by biochemical and molecular analyzes. CONCLUSIONS: The obtained results suggest that a regular intake of the probiotic product, and placebo to a lesser extent, can reduce the severity of DSS-induced colitis on rats.
Assuntos
Bifidobacterium longum , Colite/tratamento farmacológico , Enterococcus faecium , Fezes/microbiologia , Intestinos/microbiologia , Probióticos/uso terapêutico , Animais , Bebidas , Colite/induzido quimicamente , Colite/microbiologia , Sulfato de Dextrana , Modelos Animais de Doenças , Ácidos Graxos Voláteis/análise , Fezes/química , Ratos , Resultado do TratamentoRESUMO
Objective: COVID-19 is presently the most serious public health concern and diagnosis is a principal tool for controlling and monitoring the spread of the disease. This study aimed to evaluate the efficiency of direct RT-PCR (dRT-PCR) for detection of SARS-CoV-2. Methods: Twenty-seven nasopharyngeal swabs from symptomatic individuals were evaluated. Standard RT-PCR was conducted, and for dRT-PCR the samples were preheated before amplification. Results: Positive agreement was 63.2% and negative agreement was 100%, being moderately in accord. Conclusion: dRT-PCR may be an alternative for screening symptomatic patients and a reliable option during an eventual shortage of viral RNA purification kits.
Objetivo: A COVID-19 é atualmente um sério problema de saúde pública e o diagnóstico é a principal ferramenta para controlar e monitorar a propagação da doença. Este estudo teve como objetivo avaliar a eficiência da RT-PCR direta (dRT-PCR) para detecção do SARS-CoV-2. Métodos: Vinte e sete amostras de swab nasofaríngeo de indivíduos sintomáticos foram avaliados. A RT-PCR padrão foi realizada e para a dRT-PCR as amostras foram pré-aquecidas antes da amplificação. Resultados: A concordância positiva foi de 63,2% e a concordância negativa foi de 100%, sendo moderadamente concordante. Conclusão: A dRT-PCR pode ser uma alternativa para a triagem de pacientes sintomáticos e uma opção confiável durante uma eventual escassez de kits de purificação de RNA viral.