RESUMO
Pregnant women with preeclampsia (PE) present a shift in the immune response to an inflammatory profile. This deviation could be due to the interaction of tumor necrosis factor (TNF) with TNFR1 and TNFR2 receptors, besides the failure in modulation of inflammation regulatory mechanisms. This study evaluated the effects of progesterone on the expression of TNFR1 and TNFR2 by Jurkat cells after stimulation with plasma from PE and normotensive (NT) pregnant women. Jurkat cells were cultured with or without progesterone in a medium containing 20% (v/v) plasma from PE or NT women. The expression of TNF receptors was evaluated by flow cytometry. The concentration of soluble forms of TNF receptors and cytokines was determined in culture supernatant and plasma by ELISA. The plasma of PE women showed significantly higher concentrations of sTNFR1 and TNF and lower concentrations of sTNFR2 compared to the NT group. TNFR1 receptor expression was increased in Jurkat cells, while TNFR2 was decreased after culture with PE plasma when compared with Jurkat cells cultured with progesterone and plasma from NT women. The concentration of sTNFR1, TNF, and IL-10 in the culture supernatant of Jurkat cells was increased after culture with PE plasma, while the sTNFR2 receptor was decreased when compared to the NT group. Results demonstrate that in preeclamptic women a systemic inflammation occurs with an increase of inflammatory molecules, and progesterone may have a modulating effect on the expression of TNF receptors, shifting Jurkat cells towards an anti-inflammatory profile with greater expression of TNFR2.
Assuntos
Pré-Eclâmpsia , Progesterona , Receptores Tipo II do Fator de Necrose Tumoral , Receptores Tipo I de Fatores de Necrose Tumoral , Feminino , Humanos , Gravidez , Células Cultivadas , Inflamação/metabolismo , Células Jurkat , Pré-Eclâmpsia/metabolismo , Gestantes , Progesterona/metabolismo , Receptores Tipo I de Fatores de Necrose Tumoral/metabolismo , Receptores Tipo II do Fator de Necrose Tumoral/metabolismo , Fator de Necrose Tumoral alfa/metabolismoRESUMO
Previous studies have shown the relevance of high mobility group box 1 protein (HMGB1) and tumor necrosis factor α (TNFα) in nerve or tissue injury-induced nociception. However, the role of these proteins in chronic stress and social transfer of stress (STS)-induced dysfunctional pain is not entirely known. The aim of this study was to determine the participation of the spinal HMGB1-TNFα signaling pathway and TNFα receptor 1 (TNFR1) in rats subjected to chronic restraint stress (CRS) and STS. Non-stressed female and male rats in contact with CRS rats increased sniffing behavior of the anogenital area, behavior related to STS. Rats subjected to CRS and STS reduced 50 % withdrawal threshold and reached the value of tactile allodynia after 21 days of stress. Rats return to the basal withdrawal threshold after 30 days without stress and return to allodynia values in only 5 days of stress sessions (priming). Female and male rats subjected to 28 days of CRS or STS were intrathecal injected with glycyrrhizin (inhibitor of HMGB1), thalidomide (inhibitor of the TNFα synthesis), and R7050 (TNFR1 antagonist), in all the cases, an antiallodynic effect was observed. Rats under CRS or STS enhanced HMGB1 and TNFR1 protein expression in DRG and dorsal spinal cord. Data suggest that the spinal HMGB1/TNFα/TNFR1 signaling pathway plays a relevant role in the maintenance of CRS and STS-induced nociceptive hypersensitivity in rats. These proteins could be helpful in developing pain treatments for fibromyalgia in humans.
Assuntos
Proteína HMGB1 , Hiperalgesia , Humanos , Ratos , Masculino , Feminino , Animais , Receptores Tipo I de Fatores de Necrose Tumoral/efeitos adversos , Receptores Tipo I de Fatores de Necrose Tumoral/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Proteína HMGB1/efeitos adversos , Proteína HMGB1/metabolismo , Dor/induzido quimicamenteRESUMO
The TNF-α/TNFR system is involved in endometriosis (EDT), a gynecologic estrogen-dependent disease. Elevated copper concentrations have also been associated with EDT, even in TNFR1-deficient mice where disease worsening occurs. We aimed to evaluate whether treatment with ammonium tetrathiomolybdate (TM, copper chelator) is beneficial in TNFR1-deficient mice presenting with worsened EDT status. Female C57BL/6 mice were divided into three groups: KO Sham, KO EDT, and KO EDT+TM. TM was administered from the 15th postoperative day, and samples were collected one month after inducing pathology. In peritoneal fluid, copper and estradiol levels were determined by electrothermal atomic absorption spectrometry and electrochemiluminescence, respectively. Lesions were processed for the analysis of cell proliferation (PCNA immunohistochemistry), expression of angiogenic markers (RT-qPCR), and oxidative stress (spectrophotometric methods). We found that EDT increased copper and estradiol levels compared to the KO Sham group, while the TM administration restored the levels of both factors. TM also reduced the volume and weight of the lesions and cell proliferation rate. Besides, TM treatment decreased the number of blood vessels and the Vegfa, Fgf2, and Pdgfb expression. Furthermore, superoxide dismutase and catalase activity decreased, and lipid peroxidation increased. TM administration inhibits EDT progression in TNFR1-deficient mice where the pathology is exacerbated.
Assuntos
Endometriose , Receptores Tipo I de Fatores de Necrose Tumoral , Humanos , Camundongos , Feminino , Animais , Receptores Tipo I de Fatores de Necrose Tumoral/metabolismo , Cobre/metabolismo , Endometriose/metabolismo , Camundongos Endogâmicos C57BL , Quelantes/farmacologia , EstradiolRESUMO
Ulcerative colitis (UC) and Crohn's disease (CD) are part of Inflammatory Bowel Diseases (IBD) and have pathophysiological processes such as bowel necrosis and enteric neurons and enteric glial cells. In addition, the main inflammatory mediator is related to the tumor necrosis factor-alpha (TNF-α). TNF-α is a me-diator of the intestinal inflammatory processes, thus being one of the main cytokines involved in the pathogenesis of IBD, however, its levels, when measured, are present in the serum of patients with IBD. In addition, TNF-α plays an important role in promoting inflammation, such as the production of interleukins (IL), for instance IL-1ß and IL-6. There are two receptors for TNF as following: The tumor necrosis factor 1 receptor (TNFR1); and the tumor necrosis factor 2 receptor (TNFR2). They are involved in the pathogenesis of IBD and their receptors have been detected in IBD and their expression is correlated with disease activity. The soluble TNF form binds to the TNFR1 receptor with, and its activation results in a signaling cascade effects such as apoptosis, cell proliferation and cytokine secretion. In contrast, the transmembrane TNF form can bind both to TNFR1 and TNFR2. Recent studies have suggested that TNF-α is one of the main pro-inflammatory cytokines involved in the pathogenesis of IBD, since TNF levels are present in the serum of both patients with UC and CD. Intravenous and subcutaneous biologics targeting TNF-α have revolutionized the treatment of IBD, thus becoming the best available agents to induce and maintain IBD remission. The application of antibodies aimed at neutralizing TNF-α in patients with IBD that induce a satisfactory clinical response in up to 60% of patients, and also induced long-term maintenance of disease remission in most patients. It has been suggested that anti-TNF-α agents inactivate the pro-inflammatory cytokine TNF-α by direct neutralization, i.e., resulting in suppression of inflammation. However, anti-TNF-α antibodies perform more complex functions than a simple blockade.
Assuntos
Colite Ulcerativa , Doença de Crohn , Doenças Inflamatórias Intestinais , Humanos , Receptores Tipo II do Fator de Necrose Tumoral , Receptores Tipo I de Fatores de Necrose Tumoral/metabolismo , Inibidores do Fator de Necrose Tumoral , Colite Ulcerativa/tratamento farmacológico , Fator de Necrose Tumoral alfa/metabolismo , Inflamação , Citocinas/metabolismo , Doença de Crohn/tratamento farmacológicoRESUMO
Poor disease outcomes and lethality are directly related to endothelial dysfunction in betacoronavirus infections. Here, we investigated the mechanisms underlying the vascular dysfunction caused by the betacoronaviruses MHV-3 and SARS-CoV-2. Wild-type C57BL/6 (WT) and knockout mice for inducible nitric oxide synthase (iNOS-/-) or TNF receptor 1 (TNFR1-/-) were infected with MHV-3, and K18-hACE2 transgenic mice expressing human ACE2 were infected with SARS-CoV-2. Isometric tension was used to evaluate vascular function. Protein expression was determined by immunofluorescence. Tail-cuff plethysmography and Doppler were used to assess blood pressure and flow, respectively. Nitric oxide (NO) was quantified with the DAF probe. ELISA was used to assess cytokine production. Survival curves were estimated using Kaplan-Meier. MHV-3 infection reduced aortic and vena cava contractility, arterial blood pressure, and blood flow, resulting in death. Resistance mesenteric arteries showed increased contractility. The contractility of the aorta was normalized by removing the endothelium, inhibiting iNOS, genetically deleting iNOS, or scavenging NO. In the aorta, iNOS and phospho-NF-kB p65 subunit expression was enhanced, along with basal NO production. TNF production was increased in plasma and vascular tissue. Genetic deletion of TNFR1 prevented vascular changes triggered by MHV-3, and death. Basal NO production and iNOS expression were also increased by SARS-CoV-2. In conclusion, betacoronavirus induces an endothelium-dependent decrease in contractility in macro-arteries and veins, leading to circulatory failure and death via TNF/iNOS/NO. These data highlight the key role of the vascular endothelium and TNF in the pathogenesis and lethality of coronaviruses.
Assuntos
COVID-19 , Choque , Camundongos , Humanos , Animais , Óxido Nítrico Sintase Tipo II/genética , Óxido Nítrico Sintase Tipo II/metabolismo , Óxido Nítrico Sintase/metabolismo , Receptores Tipo I de Fatores de Necrose Tumoral/genética , Receptores Tipo I de Fatores de Necrose Tumoral/metabolismo , SARS-CoV-2/metabolismo , Camundongos Endogâmicos C57BL , Endotélio Vascular/metabolismo , Óxido Nítrico/metabolismo , Camundongos Transgênicos , Artérias Mesentéricas/metabolismoRESUMO
Tumor necrosis factor (TNF)-α is a pleiotropic cytokine implicated in the etiology of several autoimmune diseases, including rheumatoid arthritis (RA). TNF-α regulates diverse effector functions through the activation of TNF-α receptor (TNFR)1 and TNFR2. Although the detrimental role of this cytokine has been addressed in distinct disease settings, the effects of TNF-α on cytokine production by isolated CD4+ T helper type 1 (Th1) and Th17 cells, two T cell subpopulations that contribute to the pathogenesis of RA, have not been completely elucidated. Here, we show that TNF-α promotes a reduction and expansion in the frequency of both T cell subsets producing IFN-γ and IL-17, respectively. Selective blockade of TNFR1 or TNFR2 on Th1 and Th17 cells revealed that TNFR2 mediates the decrease in IFN-γ production, while signaling through both receptors augments IL-17 production. We also demonstrate that Th1, but not Th17 cells from RA patients present lower levels of TNFR1 compared to healthy controls, whereas TNFR2 expression on both T cell types is similar between patients and controls. Since TNF-α receptors levels in RA patients are not significantly changed by the therapeutic blockade of TNF-α, we propose that targeting TNFR2 may represent an alternative strategy to normalize the levels of key cytokines that contribute to RA pathogenesis.
Assuntos
Artrite Reumatoide , Receptores Tipo II do Fator de Necrose Tumoral , Receptores Tipo I de Fatores de Necrose Tumoral , Células Th1 , Células Th17 , Artrite Reumatoide/metabolismo , Citocinas/metabolismo , Humanos , Interleucina-17 , Receptores Tipo I de Fatores de Necrose Tumoral/metabolismo , Receptores Tipo II do Fator de Necrose Tumoral/metabolismo , Fator de Necrose Tumoral alfa/metabolismoRESUMO
BACKGROUND: Chronic inflammation due to Helicobacter pylori (H. pylori) infection promotes gastric carcinogenesis. Tumour necrosis factor-α (TNF-α), a key mediator of inflammation, induces cell survival or apoptosis by binding to two receptors (TNFR1 and TNFR2). TNFR1 can induce both survival and apoptosis, while TNFR2 results only in cell survival. The dysregulation of these processes may contribute to carcinogenesis. AIM: To evaluate the effects of TNFR1 and TNFR2 downregulation in AGS cells treated with H. pylori extract on the TNF-α pathway. METHODS: AGS cell lines containing TNFR1 and TNFR2 receptors downregulated by specific shRNAs and nonsilenced AGS cells were treated with H. pylori extract for 6 h. Subsequently, quantitative polymerase chain reaction with TaqMan® assays was used for the relative quantification of the mRNAs (TNFA, TNFR1, TNFR2, TRADD, TRAF2, CFLIP, NFKB1, NFKB2, CASP8, CASP3) and miRNAs (miR-19a, miR-34a, miR-103a, miR-130a, miR-181c) related to the TNF-α signalling pathway. Flow cytometry was employed for cell cycle analysis and apoptosis assays. RESULTS: In nonsilenced AGS cells, H. pylori extract treatment increased the expression of genes involved in cell survival and inhibited both apoptosis (NFKB1, NFKB2 and CFLIP) and the TNFR1 receptor. TNFR1 downregulation significantly decreased the expression of the TRADD and CFLIP genes, although no change was observed in the cellular process or miRNA expression. In contrast, TNFR2 downregulation decreased the expression of the TRADD and TRAF2 genes, which are both important downstream mediators of the TNFR1-mediated pathway, as well as that of the NFKB1 and CFLIP genes, while upregulating the expression of miR-19a and miR-34a. Consequently, a reduction in the number of cells in the G0/G1 phase and an increase in the number of cells in the S phase were observed, as well as the promotion of early apoptosis. CONCLUSION: Our findings mainly highlight the important role of TNFR2 in the TNF-α pathway in gastric cancer, indicating that silencing it can reduce the expression of survival and anti-apoptotic genes.
Assuntos
MicroRNAs , Neoplasias Gástricas , Fator 2 Associado a Receptor de TNF/metabolismo , Apoptose , Carcinogênese , Ciclo Celular , Regulação para Baixo , Expressão Gênica , Humanos , Inflamação , MicroRNAs/genética , Receptores Tipo I de Fatores de Necrose Tumoral/genética , Receptores Tipo I de Fatores de Necrose Tumoral/metabolismo , Receptores Tipo II do Fator de Necrose Tumoral/genética , Neoplasias Gástricas/genética , Proteína de Domínio de Morte Associada a Receptor de TNF/metabolismo , Fator 2 Associado a Receptor de TNF/genética , Fator de Necrose Tumoral alfa/metabolismoRESUMO
An insult can trigger a protective response or even cell death depending on different factors that include the duration and magnitude of the event and the ability of the cell to activate protective intracellular signals, including inflammatory cytokines. Our previous work showed that the treatment of Lister Hooded rat retinal cell cultures with 50 ng/mL phorbol 12-myristate 13-acetate (PMA), a protein kinase C activator, increases the survival of retinal ganglion cells (RGCs) kept in culture for 48 h after axotomy. Here we aim to analyze how PMA modulates the levels of TNF-α and IL-1ß (both key inflammatory mediators) and the impact of this modulation on RGCs survival. We hypothesize that the increase in RGCs survival mediated by PMA treatment depends upon modulation of the levels of IL-1ß and TNF-α. The effect of PMA treatment was assayed on cell viability, caspase 3 activation, TNF-α and IL-1ß release and TNF receptor type I (TNFRI) and TNF receptor type II (TNFRII) levels. PMA treatment increases IL-1ß and TNF-α levels in 15 min in culture and increases the release of both cytokines after 30 min and 24 h, respectively. Both IL-1ß and TNF-α levels decrease after 48 h of PMA treatment. PMA treatment also induces an increase in TNFRII levels while decreasing TNFRI after 24 h. PMA also inhibited caspase-3 activation, and decreased ROS production and EthD-1/calcein ratio in retinal cell cultures leading to an increase in cell viability. The neutralization of IL-1ß (anti-IL1ß 0,1ng/mL), the neutralization of TNF-α (anti-TNF-α 0,1ng/mL) and the TNF-α inhibition using a recombinant soluble TNFRII abolished PMA effect on RGCs survival. These data suggest that PMA treatment induces IL1ß and TNF-α release and modulation of TNFRI/TNFRII expression promoting RGCs survival after axotomy.
Assuntos
Proteína Quinase C/metabolismo , Células Ganglionares da Retina/efeitos dos fármacos , Acetato de Tetradecanoilforbol/farmacologia , Fator de Necrose Tumoral alfa/metabolismo , Animais , Animais Recém-Nascidos , Axotomia/efeitos adversos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Feminino , Interleucina-1beta/metabolismo , Masculino , Cultura Primária de Células , Ratos , Receptores Tipo I de Fatores de Necrose Tumoral/metabolismo , Receptores Tipo II do Fator de Necrose Tumoral/metabolismo , Células Ganglionares da Retina/metabolismo , Inibidores do Fator de Necrose Tumoral/farmacologia , Fator de Necrose Tumoral alfa/antagonistas & inibidoresRESUMO
Bovine leukemia virus (BLV) main host cells are B lymphocytes. Infected animals can be classified into high or low proviral load (HPL or LPL respectively), regarding the number of proviral copies infected lymphocytes they carry. After infection, there is an overexpression of several cytokines, particularly TNF-α, which has a delicate regulation mediated by receptors TNFRI and TNFRII; the first one involved with apoptosis, while the other stimulates cell proliferation. The study aimed to quantify TNF-α and its receptors mRNA expression, and in which extent in vitro proliferation was affected, in peripheral blood mononuclear cells (PBMC) from BLV-infected animals with different proviral loads, after the addition or not of synthetic TNF-α (rTNF-α) for 48 h. PBMC from BLV-infected animals showed spontaneous proliferation after 48 h in culture but did not show changes in proliferation rates after 48 h incubation in the presence of the rTNF-α. TNF-α mRNA expression after 48 h culture without exogenous stimulation was significantly lower, regardless of the proviral load of the donor, compared to non-infected animals. In the LPL animals, the expression of TNF-α mRNA was significantly lower with respect to the control group while the expression of TNFRI mRNA was significantly increased. The HPL animals showed a significant decrease in the expression of TNF-α and TNFRII mRNA respect to the control group. After 48 h incubation with rTNF-α, PBMC from infected animals had different responses: TNF-α and TNFRI mRNA expression was reduced in PBMC from the LPL group compared to the BLV negative group, but no differences were observed in PBMC from the HPL group. TNFRII mRNA expression showed no differences between HPL, LPL, and BLV negative groups, though HPL animals expressed 10.35 times more TNFRI mRNA than LPL. These results support the hypothesis that LPL animals, when faced with viral reactivation, present a pro-apoptotic and anti-proliferative state. However, complementary studies are needed to explain the influence of TNFRII on the development of the HLP profile. On the other hand, exogenous stimulation studies reinforce the hypothesis that BLV infection compromises the immune response of the animals.
Assuntos
Leucose Enzoótica Bovina/imunologia , Vírus da Leucemia Bovina/fisiologia , Receptores Tipo II do Fator de Necrose Tumoral/genética , Receptores Tipo I de Fatores de Necrose Tumoral/genética , Fator de Necrose Tumoral alfa/genética , Carga Viral , Animais , Bovinos , Proliferação de Células , Citocinas/imunologia , Leucose Enzoótica Bovina/virologia , Expressão Gênica , Sistema Imunitário , Leucócitos Mononucleares/virologia , RNA Mensageiro/genética , Receptores Tipo I de Fatores de Necrose Tumoral/metabolismo , Receptores Tipo II do Fator de Necrose Tumoral/metabolismo , Fator de Necrose Tumoral alfa/metabolismoRESUMO
Tumor necrosis factor (TNF) is one of the main cytokines regulating a pro-inflammatory environment. It has been related to several cell functions, for instance, phagocytosis, apoptosis, proliferation, mitochondrial dynamic. Moreover, during mycobacterial infections, TNF plays an essential role to maintain granuloma formation. Several effector mechanisms have been implicated according to the interactions of the two active forms, soluble TNF (solTNF) and transmembrane TNF (tmTNF), with their receptors TNFR1 and TNFR2. We review the impact of these interactions in the context of mycobacterial infections. TNF is tightly regulated by binding to receptors, however, during mycobacterial infections, upstream activation signalling pathways may be influenced by key regulatory factors either at the membrane or cytosol level. Detailing the structure and activation pathways used by TNF and its receptors, such as its interaction with solTNF/TNFRs versus tmTNF/TNFRs, may bring a better understanding of the molecular mechanisms involved in activation pathways which can be helpful for the development of new therapies aimed at being more efficient against mycobacterial infections.