RESUMO
CARD14/CARMA2sh (CARMA2sh) is a scaffold protein whose mutations are associated with the onset of human genetic psoriasis and other inflammatory skin disorders. Here we show that the immunomodulatory adapter protein TRAF family member-associated NF-κB activator (TANK) forms a complex with CARMA2sh and MALT1 in a human keratinocytic cell line. We also show that CARMA2 and TANK are individually required to activate the nuclear factor κB (NF-κB) response following exposure to polyinosinic-polycytidylic (poly [I:C]), an agonist of toll-like receptor 3. Finally, we present data indicating that TANK is essential for activation of the TBK1/IRF3 pathway following poly (I:C) stimulation, whereas CARMA2sh functions as a repressor of it. More important, we report that two CARMA2sh mutants associated with psoriasis bind less efficiently to TANK and are therefore less effective in suppressing the TBK1/IRF3 pathway. Overall, our data indicate that TANK and CARMA2sh regulate TLR3 signaling in human keratinocytes, which could play a role in the pathophysiology of psoriasis.
Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Proteínas Adaptadoras de Sinalização CARD/metabolismo , Guanilato Ciclase/metabolismo , Inflamação/metabolismo , Queratinócitos/metabolismo , Proteínas de Membrana/metabolismo , Poli I-C/metabolismo , Proteínas Adaptadoras de Sinalização CARD/genética , Linhagem Celular , Guanilato Ciclase/genética , Células HEK293 , Humanos , Fator Regulador 3 de Interferon/metabolismo , Proteínas de Membrana/genética , Mutação/genética , NF-kappa B/metabolismo , Ligação Proteica/fisiologia , Proteínas Serina-Treonina Quinases/metabolismo , Psoríase/genética , Psoríase/metabolismo , Transdução de Sinais/fisiologiaRESUMO
CARD14/CARMA2 is a scaffold molecule whose genetic alterations are linked to human inherited inflammatory skin disorders. However, the mechanisms through which CARD14/CARMA2 controls innate immune response and chronic inflammation are not well understood. By means of a yeast two-hybrid screening, we identified the UBA Domain Containing 1 (UBAC1), the non-catalytic subunit of the E3 ubiquitin-protein ligase KPC complex, as an interactor of CARMA2sh, the CARD14/CARMA2 isoform mainly expressed in human keratinocytes. UBAC1 participates in the CARMA2sh/TANK complex and promotes K63-linked ubiquitination of TANK. In human keratinocytes, UBAC1 negatively regulates the NF-κF-activating capacity of CARMA2sh following exposure to poly (I:C), an agonist of Toll-like Receptor 3. Overall, our data indicate that UBAC1 participates in the inflammatory signal transduction pathways involving CARMA2sh.
Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Proteínas Adaptadoras de Sinalização CARD/metabolismo , Guanilato Ciclase/metabolismo , Proteínas de Membrana/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Células HEK293 , Células HaCaT , Humanos , NF-kappa B/metabolismo , Ligação Proteica , Transdução de Sinais , Receptor 3 Toll-Like/metabolismo , UbiquitinaçãoRESUMO
The I-κB kinase (IKK) subunit NEMO/IKKγ (NEMO) is an adapter molecule that is critical for canonical activation of NF-κB, a pleiotropic transcription factor controlling immunity, differentiation, cell growth, tumorigenesis, and apoptosis. To explore the functional role of canonical NF-κB signaling in thyroid gland differentiation and function, we have generated a murine strain bearing a genetic deletion of the NEMO locus in thyroid. Here we show that thyrocyte-specific NEMO knock-out mice gradually develop hypothyroidism after birth, which leads to reduced body weight and shortened life span. Histological and molecular analysis indicate that absence of NEMO in thyrocytes results in a dramatic loss of the thyroid gland cellularity, associated with down-regulation of thyroid differentiation markers and ongoing apoptosis. Thus, NEMO-dependent signaling is essential for normal thyroid physiology.
Assuntos
Apoptose , Hipotireoidismo/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Glândula Tireoide/metabolismo , Animais , Peso Corporal , Feminino , Deleção de Genes , Hipotireoidismo/genética , Hipotireoidismo/patologia , Peptídeos e Proteínas de Sinalização Intracelular/genética , Masculino , Camundongos , Camundongos Knockout , NF-kappa B/metabolismo , Transdução de Sinais , Glândula Tireoide/citologia , Glândula Tireoide/patologiaRESUMO
The seven members of the tumor necrosis factor receptor (TNF-R)-associated factor (TRAF) family of intracellular proteins were originally discovered and characterized as signaling adaptor molecules coupled to the cytoplasmic regions of receptors of the TNF-R superfamily. Functionally, TRAFs act both as a scaffold and/or enzymatic proteins to regulate activation of mitogen-activated protein kinases (MAPKs) and transcription factors of nuclear factor-κB family (NF-κB). Given the wide variety of stimuli intracellularly conveyed by TRAF proteins, they are physiologically involved in multiple biological processes, including embryonic development, tissue homeostasis, and regulation of innate and adaptive immune responses. In the last few years, it has become increasingly evident the involvement of TRAF7, the last member of the TRAF family to be discovered, in the genesis and progression of several human cancers, placing TRAF7 in the spotlight as a novel tumor suppressor protein. In this paper, we review and discuss the literature recently produced on this subject. J. Cell. Physiol. 232: 1233-1238, 2017. © 2016 The Authors. Journal of Cellular Physiology Published by Wiley Periodicals, Inc.
Assuntos
Carcinogênese/metabolismo , Carcinogênese/patologia , Neoplasias/metabolismo , Neoplasias/patologia , Peptídeos e Proteínas Associados a Receptores de Fatores de Necrose Tumoral/metabolismo , Animais , Humanos , Modelos Biológicos , Mutação/genética , Domínios Proteicos , Peptídeos e Proteínas Associados a Receptores de Fatores de Necrose Tumoral/química , Peptídeos e Proteínas Associados a Receptores de Fatores de Necrose Tumoral/genéticaRESUMO
The three CARD-containing MAGUK (CARMA) proteins function as scaffolding molecules that regulate activation of the pro-inflammatory transcription factor NF-κB. Recently, mutations in CARMA2 have been linked to psoriasis susceptibility due to their acquired altered capacity to activate NF-κB. By means of two-hybrid screening with yeast, we identified RING finger protein 7 (RNF7) as an interactor of CARMA2. We present evidence that RNF7 functions as a negative regulator of the NF-κB-activating capacity of CARMA2. Mechanistically, RNF7 influences CARMA2 signaling by regulating the ubiquitination state of MALT1 and the NF-κB-regulatory molecule NEMO. Interestingly, CARMA2short (CARMA2sh) mutants associated with psoriasis susceptibility escape the negative control exerted by RNF7. In conclusion, our findings identify a new mechanism through which the ability of CARMA2 to activate NF-κB is regulated, which could have significant implications for our understanding of why mutations of this protein trigger human psoriasis.
Assuntos
Proteínas Adaptadoras de Sinalização CARD/genética , Proteínas Adaptadoras de Sinalização CARD/metabolismo , Guanilato Ciclase/genética , Guanilato Ciclase/metabolismo , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Transdução de Sinais , Ubiquitina-Proteína Ligases/metabolismo , Proteínas Adaptadoras de Sinalização CARD/química , Linhagem Celular , Regulação da Expressão Gênica , Guanilato Ciclase/química , Células HEK293 , Humanos , Quinase I-kappa B/metabolismo , Proteínas de Membrana/química , Proteína de Translocação 1 do Linfoma de Tecido Linfoide Associado à Mucosa/metabolismo , Mutação , NF-kappa B/metabolismo , Ligação Proteica , Ubiquitina-Proteína Ligases/química , UbiquitinaçãoRESUMO
Initially identified by their ability to modulate the functional activity of BCL10, the three CARMA proteins, CARMA1, -2, and -3, have recently themselves taken a leading role on the stage of molecular medicine. Although considered for some time as simple ancillary proteins, increasingly accumulating recent data evidently indicate a role of primary importance for these three proteins in the pathophysiology of several human tumors and inflammatory disorders. In fact, recent scientific literature clearly establishes that CARMA1 is one of the most mutated genes in a subtype of B-cell lymphoma and, at the same time, responsible for some rare human immunodeficiency conditions. On the other hand, mutations in CARMA2 are responsible for the hereditary transmission of some inflammatory disorders of the skin, including familial psoriasis and ptiriasis; whereas expression of CARMA3 appears to be deregulated in different human tumors. Here we describe and summarize the mutations found in the genes coding for the three CARMA proteins in these different human pathological conditions, and offer an interpretation of the molecular mechanisms from which arise the biological outcomes in which these proteins are involved.
Assuntos
Proteínas Adaptadoras de Sinalização CARD/metabolismo , Guanilato Ciclase/metabolismo , Inflamação/metabolismo , Proteínas de Membrana/metabolismo , Neoplasias/metabolismo , Proteínas Adaptadoras de Sinalização CARD/genética , Regulação da Expressão Gênica/fisiologia , Guanilato Ciclase/genética , Humanos , Inflamação/genética , Proteínas de Membrana/genética , Neoplasias/genéticaRESUMO
Colorectal cancer (CRC) is a significant global health challenge, ranking among the leading causes of cancer-related mortality worldwide. Despite efforts in prevention and early detection, CRC incidence and mortality rates are expected to rise substantially. Traditional screening methods like gFOBT, FIT, flexible sigmoidoscopy, colonoscopy, CTC, and colon capsule have limitations, including false positives/negatives, limited scope, or invasiveness. Recent developments in CRC screening involve DNA methylation biomarkers, showing promise in detecting early-stage CRC and precancerous lesions. Stool-based DNA testing is emerging as a noninvasive and convenient method for detecting CRC-associated DNA methylation alterations, offering potential for earlier detection compared to traditional methods. Several commercial stool-based DNA methylation tests targeting different genes associated with CRC have demonstrated varying sensitivity and specificity, some surpassing traditional screening methods. Challenges remain in optimizing their performance and accessibility. This review discusses how DNA methylation biomarkers could enhance CRC screening, and stool-based DNA methylation tests could revolutionize CRC screening practices, comparing them to the gold standard.
RESUMO
Glucocorticoids (GCs) are widely used as powerful anti-inflammatory and immunosuppressive therapeutics in multiple pathological conditions. However, compelling evidence indicates that they might promote neurodegeneration by altering mitochondrial homeostatic processes. Although the effect of dexamethasone on cell survival and homeostasis has been widely investigated, the effect of other glucocorticoids needs to be explored in more detail. In this report, we have compared the neurotoxicity induced by dexamethasone, prednisolone, betamethasone, and hydrocortisone in cultured neuroblastoma cells, through the analysis of several parameters such as cell viability, ER stress, oxidative stress, and mitochondrial fusion and fission markers. Interestingly, we have found that synthetic glucocorticoids may impact neuronal viability by affecting different cellular responses, suggesting that their therapeutic use should be consciously decided after careful consideration of benefits and detrimental effects.
Assuntos
Sobrevivência Celular , Glucocorticoides , Neuroblastoma , Estresse Oxidativo , Glucocorticoides/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Neuroblastoma/patologia , Linhagem Celular Tumoral , Humanos , Estresse Oxidativo/efeitos dos fármacos , Estresse Oxidativo/fisiologia , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Estresse do Retículo Endoplasmático/fisiologia , Dexametasona/farmacologia , Hidrocortisona/farmacologia , Prednisolona/farmacologia , Betametasona/farmacologia , Neurônios/efeitos dos fármacos , Neurônios/metabolismoRESUMO
Progressive cartilage deterioration leads to chronic inflammation and loss of joint function, causing osteoarthritis (OA) and joint disease. Although symptoms vary among individuals, the disease can cause severe pain and permanent disability, and effective therapies are urgently needed. Human Adipose-Derived Stem Cells (ADSCs) may differentiate into chondrocytes and are promising for treating OA. Moreover, recent studies indicate that electromagnetic fields (EMFs) could positively affect the chondrogenic differentiation potential of ADSCs. In this work, we investigated the impact of EMFs with frequencies of 35 Hertz and 58 Hertz, referred to as extremely low frequency-EMFs (ELF-EMFs), on the chondrogenesis of ADSCs, cultured in both monolayer and 3D cell micromasses. ADSC cultures were daily stimulated for 36 min with ELF-EMFs or left unstimulated, and the progression of the differentiation process was evaluated by morphological analysis, extracellular matrix deposition, and gene expression profiling of chondrogenic markers. In both culturing conditions, stimulation with ELF-EMFs did not compromise cell viability but accelerated chondrogenesis by enhancing the secretion and deposition of extracellular matrix components at earlier time points in comparison to unstimulated cells. This study showed that, in an appropriate chondrogenic microenvironment, ELF-EMFs enhance chondrogenic differentiation and may be an important tool for supporting and accelerating the treatment of OA through autologous adipose stem cell therapy.
Assuntos
Tecido Adiposo , Diferenciação Celular , Condrogênese , Campos Eletromagnéticos , Células-Tronco Mesenquimais , Humanos , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/metabolismo , Tecido Adiposo/citologia , Células Cultivadas , Condrócitos/citologia , Condrócitos/metabolismo , Matriz Extracelular/metabolismo , Sobrevivência Celular/efeitos da radiaçãoRESUMO
(1) Background: Dry eye disease (DED) is a multifactorial ocular surface disease characterized by an imbalance in ocular surface homeostasis, and tear substitutes constitute the first line of treatment. The present study aimed to evaluate the changes in the signs and symptoms of patients with DED treated with a novel tear substitute containing the GlicoPro® complex. (2) Methods: Patients with DED not successfully responding to other tear substitutes were enrolled and treated with a novel ophthalmic solution (two drops four times daily). Patients were examined before starting the study treatment (T0) and after 30 (T1) and 60 (T2) days of treatment by means of Keratograph for the evaluation of the following: (i) tear meniscus height (TMH); (ii) noninvasive Keratograph break-up time (NIKBUT); (iii) bulbar redness; and (iv) infrared meibography. The SANDE questionnaire was administered to assess ocular discomfort symptoms. Analysis of the tear content of proenkephalin and Met/Leu-enkephalin was also performed. (3) Results: At T2, a significant improvement in NIKBUT first, average, and class, TMH, and SANDE score was found. The tear content of proenkephalins was significantly higher at T1, whereas processed active Met/Leu-enkephalins increased at both T1 and T2. (4) Conclusions: Our novel tear substitute based on GlicoPro® resulted in a significant improvement in ocular discomfort symptoms, tear volume, and stability in the patients treated. The increase in active peptides processed in tears may represent the pathophysiological substrate underlying this finding.
RESUMO
The molecular complexes containing CARMA proteins have been recently identified as a key components in the signal transduction pathways that regulate activation of nuclear factor κB (NF-κB) transcription factor. Here, we used immunoprecipitation coupled with mass spectrometry to identify cellular binding partners of CARMA proteins. Our data indicate that the Rho guanine nucleotide exchange factor Net1 binds to CARMA1 and CARMA3 in resting and activated cells. Net1 expression induces NF-κB activation and cooperates with BCL10 and CARMA proteins in inducing NF-κB activity. Conversely, shRNA-mediated abrogation of Net1 results in impaired NF-κB activation following stimuli that require correct CARMA-BCL10-MALT1 complex formation and functioning. Microarray expression data are consistent with a positive role for Net1 on NF-κB activation. Thus, this study identifies Net1 as a CARMA-interacting molecule and brings important information on the molecular mechanisms that control NF-κB transcriptional activity.
Assuntos
Caspases/metabolismo , Proteínas Oncogênicas/metabolismo , Proteínas Adaptadoras de Sinalização CARD/química , Ativação Enzimática , Ensaio de Imunoadsorção Enzimática/métodos , Células HEK293 , Humanos , Proteínas I-kappa B/metabolismo , Células Jurkat , Leucócitos Mononucleares/citologia , Inibidor de NF-kappaB alfa , Análise de Sequência com Séries de Oligonucleotídeos , Fosforilação , Estrutura Terciária de Proteína , RNA/química , Transdução de Sinais , TransfecçãoRESUMO
The pro-inflammatory cytokine tumor necrosis factor (TNF) α signals both cell survival and death. The biological outcome of TNFα treatment is determined by the balance between survival factors and Jun NH(2)-terminal kinase (JNK) signaling, which promotes cell death. Here, we show that TRAF7, the most recently identified member of the TNF receptor-associated factors (TRAFs) family of proteins, is essential for activation of JNK following TNFα stimulation. We also show that TRAF6 and TRAF7 promote unconventional polyubiquitination of the anti-apoptotic protein c-FLIP(L) and demonstrate that degradation of c-FLIP(L) also occurs through a lysosomal pathway. RNA interference-mediated depletion of TRAF7 correlates with increased c-FLIP(L) expression level, which, in turn, results in resistance to TNFα cytotoxicity. Collectively, our results indicate an important role for TRAF7 in the activation of JNK following TNFα stimulation and clearly point to an involvement of this protein in regulating the turnover of c-FLIP and, consequently, cell death.
Assuntos
Proteína Reguladora de Apoptosis Semelhante a CASP8 e FADD/metabolismo , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Lisossomos/metabolismo , Poliubiquitina/metabolismo , Proteólise/efeitos dos fármacos , Peptídeos e Proteínas Associados a Receptores de Fatores de Necrose Tumoral/metabolismo , Fator de Necrose Tumoral alfa/farmacologia , Morte Celular/efeitos dos fármacos , Ativação Enzimática/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Técnicas de Silenciamento de Genes , Células HEK293 , Células HeLa , Humanos , Células Jurkat , Lisossomos/efeitos dos fármacos , RNA Interferente Pequeno/genética , Peptídeos e Proteínas Associados a Receptores de Fatores de Necrose Tumoral/deficiência , Peptídeos e Proteínas Associados a Receptores de Fatores de Necrose Tumoral/genética , Ubiquitinação/efeitos dos fármacosRESUMO
Long-lived individuals (LLIs) are considered an ideal model to study healthy human aging. Blood fatty acid (FA) profile of a cohort of LLIs (90-111 years old, n = 49) from Sicily was compared to adults (18-64 years old, n = 69) and older adults (65-89 years old, n = 54) from the same area. Genetic variants in key enzymes related to FA biosynthesis and metabolism were also genotyped to investigate a potential genetic predisposition in determining the FA profile. Gas chromatography was employed to determine the FA profile, and genotyping was performed using high-resolution melt (HRM) analysis. Blood levels of total polyunsaturated FA (PUFA) and total trans-FA decreased with age, while the levels of saturated FA (SFA) remained unchanged. Interestingly, distinctively higher circulatory levels of monounsaturated FA (MUFA) in LLIs compared to adults and older adults were observed. In addition, among LLIs, rs174537 in the FA desaturase 1/2 (FADS1/2) gene was associated with linoleic acid (LA, 18:2n-6) and docosatetraenoic acid (DTA, 22:4n-6) levels, and the rs953413 in the elongase of very long FA 2 (ELOVL2) was associated with DTA levels. We further observed that rs174579 and rs174626 genotypes in FADS1/2 significantly affect delta-6 desaturase (D6D) activity. In conclusion, our results suggest that the LLIs have a different FA profile characterized by high MUFA content, which indicates reduced peroxidation while maintaining membrane fluidity.
Assuntos
Ácidos Graxos Monoinsaturados , Ácidos Graxos , Humanos , Idoso , Idoso de 80 Anos ou mais , Ácidos Graxos Monoinsaturados/análise , Ácidos Graxos Monoinsaturados/metabolismoRESUMO
Combining exercise with fasting is known to boost fat mass-loss, but detailed analysis on the consequential mobilization of visceral and subcutaneous WAT-derived fatty acids has not been performed. In this study, a subset of fasted male rats (66 h) was submitted to daily bouts of mild exercise. Subsequently, by using gas chromatography-flame ionization detection, the content of 22 fatty acids (FA) in visceral (v) versus subcutaneous (sc) white adipose tissue (WAT) depots was compared to those found in response to the separate events. Findings were related to those obtained in serum and liver samples, the latter taking up FA to increase gluconeogenesis and ketogenesis. Each separate intervention reduced scWAT FA content, associated with increased levels of adipose triglyceride lipase (ATGL) protein despite unaltered AMP-activated protein kinase (AMPK) Thr172 phosphorylation, known to induce ATGL expression. The mobility of FAs from vWAT during fasting was absent with the exception of the MUFA 16:1 n-7 and only induced by combining fasting with exercise which was accompanied with reduced hormone sensitive lipase (HSL) Ser563 and increased Ser565 phosphorylation, whereas ATGL protein levels were elevated during fasting in association with the persistently increased phosphorylation of AMPK at Thr172 both during fasting and in response to the combined intervention. As expected, liver FA content increased during fasting, and was not further affected by exercise, despite additional FA release from vWAT in this condition, underlining increased hepatic FA metabolism. Both fasting and its combination with exercise showed preferential hepatic metabolism of the prominent saturated FAs C:16 and C:18 compared to the unsaturated FAs 18:1 n-9 and 18:2 n-6:1. In conclusion, depot-specific differences in WAT fatty acid molecule release during fasting, irrelevant to their degree of saturation or chain length, are mitigated when combined with exercise, to provide fuel to surrounding organs such as the liver which is correlated with increased ATGL/ HSL ratios, involving AMPK only in vWAT.
Assuntos
Ácidos Graxos , Esterol Esterase , Ratos , Masculino , Animais , Esterol Esterase/metabolismo , Ácidos Graxos/metabolismo , Proteínas Quinases Ativadas por AMP/metabolismo , Lipase/metabolismo , Lipólise/fisiologia , Obesidade/metabolismo , Jejum/metabolismo , Tecido Adiposo/metabolismoRESUMO
Tumor necrosis factor receptor-associated factor (TRAF) proteins are cytoplasmic regulatory molecules that function as signal transducers for receptors involved in both innate and adaptive humoral immune responses. In this study, we show that TRAF7, the unique noncanonical member of the TRAF family, physically associates with IκB kinase/NF-κB essential modulator (NEMO) and with the RelA/p65 (p65) member of the NF-κB transcription factor family. TRAF7 promotes Lys-29-linked polyubiquitination of NEMO and p65 that results in lysosomal degradation of both proteins and altered activation. TRAF7 also influences p65 nuclear distribution. Microarray expression data are consistent with an inhibitory role for TRAF7 on NF-κB and a positive control of AP-1 transcription factor. Finally, functional data indicate that TRAF7 promotes cell death. Thus, this study identifies TRAF7 as a NEMO- and p65-interacting molecule and brings important information on the ubiquitination events that control NF-κB transcriptional activity.
Assuntos
Núcleo Celular/metabolismo , Quinase I-kappa B/metabolismo , Fator de Transcrição RelA/metabolismo , Transcrição Gênica/fisiologia , Peptídeos e Proteínas Associados a Receptores de Fatores de Necrose Tumoral/metabolismo , Ubiquitinação/fisiologia , Transporte Ativo do Núcleo Celular/fisiologia , Imunidade Adaptativa/fisiologia , Morte Celular , Núcleo Celular/genética , Núcleo Celular/imunologia , Células HEK293 , Células HeLa , Humanos , Quinase I-kappa B/genética , Quinase I-kappa B/imunologia , Imunidade Inata/fisiologia , Lisossomos/genética , Lisossomos/imunologia , Lisossomos/metabolismo , Fator de Transcrição AP-1/genética , Fator de Transcrição AP-1/imunologia , Fator de Transcrição AP-1/metabolismo , Fator de Transcrição RelA/genética , Fator de Transcrição RelA/imunologia , Peptídeos e Proteínas Associados a Receptores de Fatores de Necrose Tumoral/genética , Peptídeos e Proteínas Associados a Receptores de Fatores de Necrose Tumoral/imunologiaRESUMO
Tumor necrosis factor receptor-associated factors (TRAFs) have been discovered and characterized by their capacity to link tumor necrosis factor receptors (TNFR) family proteins to signaling pathways that transduce the cellular effects mediated by TNF family ligands. There are seven known mammalian TRAF proteins (TRAF1-7), that share a domain organization made of a modular structure, characteristic of adaptor proteins whose function is to link structurally dissimilar factors. Functionally, TRAF proteins mediate the assembly of cytoplasmic signal transducers and regulatory molecules downstream of receptors complexes. Despite the similarities in the signaling pathways activated by the different TRAF proteins, each appears to play distinct physiological roles. TRAF7 is the last member of the TRAF family that has been identified. Yet, the functional characterization of TRAF7 presents some aspects still obscure and poorly defined, making this protein arguably the most mysterious member of the family. In fact, recent data indicate that TRAF7 is involved in signal transduction pathways that lead either to activation or repression of NF-κB transcription factor. In addition, TRAF7 regulates activation of cellular stress pathways, as well as unconventional ubiquitination events and differentiation of muscle tissue. In this review, we try to summarize the most recent advances in our understanding of TRAF7 function and the biological processes of this protein is involved in.
Assuntos
Transdução de Sinais/fisiologia , Peptídeos e Proteínas Associados a Receptores de Fatores de Necrose Tumoral/fisiologia , Animais , Regulação para Baixo/fisiologia , Humanos , Camundongos , Camundongos Knockout , NF-kappa B/antagonistas & inibidores , NF-kappa B/biossíntese , Transdução de Sinais/genética , Peptídeos e Proteínas Associados a Receptores de Fatores de Necrose Tumoral/deficiência , Peptídeos e Proteínas Associados a Receptores de Fatores de Necrose Tumoral/genética , Regulação para Cima/fisiologiaRESUMO
The use of medical devices, such as contact lenses, represents a substantial risk of infection, as they can act as scaffolds for formation of microbial biofilms. Recently, the increasing emergency of antibiotic resistance has prompted the development of novel and effective antimicrobial drugs for biofilm treatment, such as oxidizing agents. The purpose of this study is to investigate the effects of Ozodrop® and Ozodrop® gel, commercial names of ozonated oil in liposomes plus hypromellose, on eradication and de novo formation of biofilms on different supports, such as plastic plates and contact lens. Our results demonstrate that ozonated liposomal sunflower oil plus hypromellose have an excellent inhibitory effect on bacterial viability and on both de novo formation and eradication of biofilms produced on plates and contact lens by Pseudomonas aeruginosa and Staphylococcus aureus. Moreover, we show that Ozodrop® formulations stimulate expression of antimicrobial peptides and that Ozodrop® gel has a strong repair activity on human epithelial cells, suggesting further applications for the treatment of non-healing infected wounds.
Assuntos
Lipossomos , Pseudomonas aeruginosa , Antibacterianos/farmacologia , Biofilmes , Humanos , Derivados da Hipromelose/farmacologia , Lipossomos/farmacologia , Testes de Sensibilidade Microbiana , Staphylococcus aureusRESUMO
Molecular tests are the gold standard to diagnose severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection but are associated with a diagnostic delay, while antigen detection tests can generate results within 20 min even outside a laboratory. In order to evaluate the accuracy and reliability of the FAST COVID-19 SARS-CoV-2 Antigen Rapid Test Kit (Ag-RDT), two respiratory swabs were collected simultaneously from 501 patients, with mild or no coronavirus disease 2019 (COVID-19)-related symptoms, and analyzed with both the Reverse Transcriptase-quantitative Polymerase Chain Reaction (RT-qPCR) and the FAST COVID-19 SARS-CoV-2 Antigen Rapid Test. Results were then compared to determine clinical performance in a screening setting. We measured a precision of 97.41% (95% CI 92.42-99.15%) and a recall of 98.26% (95% CI 93.88-99.25%), with a specificity of 99.22% (95% CI 97.74-99.74%), a negative predictive value of 99.48% (95% CI 97.98-99.87%), and an overall accuracy of 99.00% (95% CI 97.69-99.68%). Concordance was described by a Kappa coefficient of 0.971 (95% CI 0.947-0.996). Considering short lead times, low cost, and opportunities for decentralized testing, the Ag-RDT test can enhance the efforts to control SARS-CoV-2 spread in several settings.
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SARS-CoV-2 virus is responsible for the current worldwide coronavirus disease 2019 (COVID-19) pandemic, infecting millions of people and causing hundreds of thousands of deaths. Understanding the antibody response to SARS-CoV-2 is crucial for the development of vaccines, therapeutics and public health interventions. However, lack of consistency in methods used to monitor antibody response to SARS-CoV-2 leaves some uncertainty in our fine understanding of the human antibody response mounted following SARS-CoV-2 infection. We developed a peptide-based enzyme-linked immunosorbent assay (ELISA) by selecting 7 synthetic peptides from the spike, membrane, and nucleocapsid protein sequences of SARS-CoV-2, which effectively detects the antibody response mounted by all COVID-19 convalescent tested. Strikingly, the assay shows a profound difference in antibody response among individual subjects, which may have a significant impact on disease severity. Together, our results define an efficient and specific serological assay to consistently measure the antibody response following SARS-CoV-2 infection, as well as help the design of vaccine and therapeuticals for prevention and treatment of COVID-19.
RESUMO
In the COVID-19 pandemic year 2021, several countries have implemented a vaccine certificate policy, the "Green Pass Policy" (GPP), to reduce virus spread and to allow safe relaxation of COVID-19 restrictions and reopening of social and economic activities. The rationale for the GPP is based on the assumption that vaccinated people should maintain a certain degree of immunity to SARS-CoV-2. Here we describe and compare, for the first time, the humoral immune response to mRNA-1273, BNT162b2, Ad26.COV2.S, and ChAdOx1 nCoV-19 vaccines in terms of antibody titer elicited, neutralizing activity, and epitope reactogenicity among 369 individuals aged 19 to 94 years. In parallel, we also considered the use of a rapid test for the determination of neutralizing antibodies as a tool to guide policymakers in defining booster vaccination strategies and eligibility for Green Pass. Our analysis demonstrates that the titer of antibodies directed towards the receptor-binding domain (RBD) of SARS-CoV-2 Spike is significantly associated with age and vaccine type. Moreover, natural COVID-19 infection combined with vaccination results, on average, in higher antibody titer and higher neutralizing activity as compared to fully vaccinated individuals without prior COVID-19. We also found that levels of anti-Spike RBD antibodies are not always strictly associated with the extent of inhibition of RBD-ACE2 binding, as we could observe different neutralizing activities in sera with similar anti-RBD concentrations. Finally, we evaluated the reactivity to four synthetic peptides derived from Spike protein on a randomly selected serum sample and observed that similar to SARS-CoV-2 infection, vaccination elicits a heterogeneous antibody response with qualitative individual features. On the basis of our results, the use of rapid devices to detect the presence of neutralizing antibodies, even on a large scale and repeatedly over time, appears helpful in determining the duration of the humoral protection elicited by vaccination. These aspects and their implications for the GPP are discussed.