RESUMEN
Type 1 interferons (IFNs) promote inflammation in the skin but the mechanisms responsible for inducing these cytokines are not well understood. We found that IFN-ß was abundantly produced by epidermal keratinocytes (KCs) in psoriasis and during wound repair. KC IFN-ß production depended on stimulation of mitochondrial antiviral-signaling protein (MAVS) by the antimicrobial peptide LL37 and double stranded-RNA released from necrotic cells. MAVS activated downstream TBK1 (TANK-Binding Kinase 1)-AKT (AKT serine/threonine kinase 1)-IRF3 (interferon regulatory factor 3) signaling cascade leading to IFN-ß production and then promoted maturation of dendritic cells. In mice, the production of epidermal IFN-ß by LL37 required MAVS, and human wounded and/or psoriatic skin showed activation of MAVS-associated IRF3 and induction of MAVS and IFN-ß gene signatures. These findings show that KCs are an important source of IFN-ß and MAVS is critical to this function, and demonstrates how the epidermis triggers unwanted skin inflammation under disease conditions.
Asunto(s)
Catelicidinas/metabolismo , Células Dendríticas/fisiología , Epidermis/patología , Queratinocitos/inmunología , Mitocondrias/metabolismo , Psoriasis/inmunología , Heridas y Lesiones/inmunología , Proteínas Adaptadoras Transductoras de Señales/genética , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Animales , Péptidos Catiónicos Antimicrobianos , Catelicidinas/genética , Diferenciación Celular , Células Cultivadas , Humanos , Interferón beta/metabolismo , Ratones , Ratones Noqueados , ARN Interferente Pequeño/genética , Transducción de Señal , Cicatrización de HeridasRESUMEN
Accumulating evidence revealed the abnormal expression of KLF5 in human cancers while its role in melanoma remains uncharacterized. This study aimed to explore the role of KLF5 in the proliferation and metastasis of melanoma. Bioinformatics analysis was performed to detect WWP1, BAP1 and KLF5 expression in melanoma, followed by expression determination on clinical tissues from melanoma patients and cancer cells. The cancer cells were infected with lentivirus expressing KLF5 or BAP1 while PI3K, AKT and mTOR expression was detected and autophagy was observed. Treated cells were injected to mice when tumor growth was measured and autophagy-related protein was detected. Plasmids expressing WWP1 and Ub-K48 were co-transfected into treated melanoma cells while immunoprecipitation assay was performed to determine the interaction among KLF5, WWP1, and BAP1. WWP1 was poorly expressed in melanoma cells and tissues whereas KLF5 was highly expressed and was positively correlated to poor prognosis. KLF5 promoted melanoma cell malignant phenotypes as well as inhibited autophagy. Interestingly, KLF5 contributed to activation of PI3K-AKT-mTOR signaling pathway, thereby inhibiting autophagy in melanoma cells. WWP1 mediated K48-linked ubiquitination of KLF5 to promote its degradation, and BAP1 antagonized this modification and stabilized KLF5 protein expression. Besides, BAP1 promoted KLF5-mediated growth of melanoma in vivo. Taken altogether, BAP1 antagonized WWP1-mediated ubiquitination of KLF5 to inhibit autophagy and promote melanoma development.
Asunto(s)
Factores de Transcripción de Tipo Kruppel/genética , Melanoma/genética , Proteínas Supresoras de Tumor/genética , Ubiquitina Tiolesterasa/genética , Ubiquitina-Proteína Ligasas/genética , Adulto , Anciano , Animales , Autofagia/genética , Línea Celular Tumoral , Proliferación Celular/genética , Progresión de la Enfermedad , Femenino , Regulación Neoplásica de la Expresión Génica , Xenoinjertos , Humanos , Masculino , Melanoma/patología , Ratones , Persona de Mediana Edad , Proteínas Proto-Oncogénicas c-akt/genética , Serina-Treonina Quinasas TOR/genética , Ubiquitinación/genéticaRESUMEN
Group A Streptococcus (GAS) is a preeminent human bacterial pathogen causing hundreds of millions of infections each year worldwide. In the clinical setting, the bacterium is easily identified by a rapid antigen test against the group A carbohydrate (GAC), a polysaccharide that comprises 30 to 50% of the GAS cell wall by weight. Originally described by Rebecca Lancefield in the 1930s, GAC consists of a polyrhamnose backbone and a N-acetylglucosamine (GlcNAc) side chain. This side chain, the species-defining immunodominant antigen, is potentially implicated in autoreactive immune responses against human heart or brain tissue in poststreptococcal rheumatic fever or rheumatic heart disease. The recent discovery of the genetic locus encoding GAC biosynthesis and new insights into its chemical structure have provided novel insights into the assembly of the polysaccharide, its contribution to immune evasion and virulence, and ideas for safely harnessing its natural immunogenicity in vaccine design. This minireview serves to summarize the emerging new literature on GAC, the eponymous cell well antigen that provides structural integrity to GAS and directly interfaces with host innate and adaptive immune responses.
Asunto(s)
Interacciones Huésped-Patógeno/inmunología , Polisacáridos Bacterianos/inmunología , Infecciones Estreptocócicas/inmunología , Infecciones Estreptocócicas/microbiología , Streptococcus pyogenes/inmunología , Antígenos Bacterianos/inmunología , Susceptibilidad a Enfermedades , Humanos , Inmunidad , Infecciones Estreptocócicas/prevención & control , Virulencia , Factores de VirulenciaRESUMEN
Radiation-induced dermatitis is a common and serious side effect after radiotherapy. Current clinical treatments cannot efficiently or fully prevent the occurrence of post-irradiation dermatitis, which remains a significant clinical problem. Resolving this challenge requires gaining a better understanding of the precise pathophysiology, which in turn requires establishment of a suitable animal model that mimics the clinical condition, and can also be used to investigate the mechanism and explore effective treatment options. In this study, a single dose of 90 Gy irradiation to rats resulted in ulceration, dermal thickening, inflammation, hair follicle loss, and sebaceous glands loss, indicating successful establishment of the model. Few hair follicle cells migrated to form epidermal cells, and both the severity of skin fibrosis and hydroxyproline levels increased with time post-irradiation. Radiation damaged the mitochondria and induced both apoptosis and autophagy of the skin cells. Therefore, irradiation of 90 Gy can be used to successfully establish a rat model of radiation-induced dermatitis. This model will be helpful for developing new treatments and gaining a better understanding of the pathological mechanism of radiation-induced dermatitis. Specifically, our results suggest autophagy regulation as a potentially effective therapeutic target.
Asunto(s)
Modelos Animales de Enfermedad , Neoplasias/radioterapia , Traumatismos Experimentales por Radiación/patología , Radiodermatitis/patología , Animales , Apoptosis/efectos de la radiación , Movimiento Celular/efectos de la radiación , Folículo Piloso/patología , Folículo Piloso/efectos de la radiación , Humanos , Neoplasias/complicaciones , Dosis de Radiación , Radioterapia/efectos adversos , Ratas , Piel/patología , Piel/efectos de la radiaciónRESUMEN
Sodium phenylbutyrate (PBA) is a derivative of the short-chain fatty acid butyrate and is approved for treatment of urea cycle disorders and progressive familial intrahepatic cholestasis type 2. Previously known functions include histone deacetylase inhibitor, endoplasmic reticulum stress inhibitor, ammonia sink, and chemical chaperone. Here, we show that PBA has a previously undiscovered protective role in host mucosal defense during infection. Administration of PBA to Taconic mice resulted in the increase of intestinal Lactobacillales and segmented filamentous bacteria (SFB), as well as an increase of interleukin 17 (IL-17) production by intestinal cells. This effect was not observed in Jackson Laboratory mice, which are not colonized with SFB. Because previous studies showed that IL-17 plays a protective role during infection with mucosal pathogens, we hypothesized that Taconic mice treated with PBA would be more resistant to infection with Salmonella enterica serovar Typhimurium (S Typhimurium). By using the streptomycin-treated mouse model, we found that Taconic mice treated with PBA exhibited significantly lower S Typhimurium intestinal colonization and dissemination to the reticuloendothelial system, as well as lower levels of inflammation. The lower levels of S Typhimurium gut colonization and intestinal inflammation were not observed in Jackson Laboratory mice. Although PBA had no direct effect on bacterial replication, its administration reduced S Typhimurium epithelial cell invasion and lowered the induction of the proinflammatory cytokine IL-23 in macrophage-like cells. These effects likely contributed to the better outcome of infection in PBA-treated mice. Overall, our results suggest that PBA induces changes in the microbiota and in the mucosal immune response that can be beneficial to the host during infection with S Typhimurium and possibly other enteric pathogens.
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Fenilbutiratos/administración & dosificación , Salmonelosis Animal/tratamiento farmacológico , Salmonella typhimurium/efectos de los fármacos , Animales , Modelos Animales de Enfermedad , Inmunidad Mucosa/inmunología , Inflamación/inmunología , Inflamación/metabolismo , Inflamación/microbiología , Interleucina-17/metabolismo , Interleucina-23/metabolismo , Intestinos/inmunología , Intestinos/microbiología , Lactobacillales/efectos de los fármacos , Lactobacillales/inmunología , Lactobacillales/metabolismo , Ratones , Ratones Endogámicos C57BL , Salmonelosis Animal/inmunología , Salmonelosis Animal/microbiología , Salmonella typhimurium/inmunología , Estreptomicina/farmacologíaRESUMEN
Men historically consume more meat than women, show fewer intentions to reduce meat consumption, and are underrepresented among vegans and vegetarians. Eating meat strongly aligns with normative masculinities, decisively affirming that "real men" eat meat and subordinating men who choose to be veg*n (vegan or vegetarian). The emergence of meat alternatives and increasing environmental concerns may contest these long-standing masculine norms and hierarchies. The current scoping review addresses the research question what are the connections between masculinities and men's attitudes and behaviors toward meat consumption and veg*nism? Using keywords derived from two key concepts, "men" and "meat," 39 articles were selected and analyzed to inductively derive three thematic findings; (a) Meat as Masculine, (b) Veg*n Men as Othered, and (c) Veg*nism as Contemporary Masculinity. Meat as Masculine included how men's gendered identities, defenses, and physicalities were entwined with meat consumption. Veg*n Men as Othered explored the social and cultural challenges faced by men who adopt meatless diets, including perceptions of emasculation. Veg*nism as Contemporary Masculinity was claimed by men who eschewed meat in their diets and advocated for veg*nism as legitimate masculine capital through linkages to physical strength, rationality, self-determination, courage, and discipline. In light of the growing concern about the ecological impact of meat production and the adverse health outcomes associated with its excessive consumption, this review summarizes empirical connections between masculinities and the consumption of meat to consider directions for future men's health promotion research, policy, and practice.
Asunto(s)
Masculinidad , Carne , Humanos , Masculino , Dieta Vegana , Salud del Hombre , Dieta Vegetariana/psicologíaRESUMEN
Shifts in gender roles, identities and relations since the 1980s are continuing to influence masculinities within intimate partner relationships. Forefront in men's contemporary heterosexual relationships have been calls for gender equality and gender equity as a means to promoting the mental health and well-being of partners and their families. Most previous research has focused on a pathologized role of men in relationships (e.g., intimate partner violence). Little is known about how men perceive intimate partner relationships using a strength-based perspective. The current photovoice study addressed the research question, 'What are the connections between masculinities and men's heterosexual intimate partner relationships?' to highlight young men's (19-43 years-old) experiences of, and perspectives about their intimate partner relationships. Drawing from individual Zoom interviews with 92 heterosexual, cisgender men from 14 countries, we abductively derived three masculine typologies: 1) neo-traditionalist, 2) egalitarian and 3) progressive. Twenty-two (24%) participants embodied neo-traditionalist masculinities characterized by reliance's on traditional masculine norms that assign domesticities as feminine and prize masculine breadwinner and protector roles. Half of the participants (50%, n = 46) purposefully distanced themselves from traditional masculine norms to engage egalitarian masculinities. These men idealized equal (50-50) contributions and reciprocity wherein counts were often used to evaluate each partner's relative efforts and contributions to the relationship. Progressive masculinities were evident in 26% (n = 24) of participants who focused on fairness and social justice, checking their own privilege to justly operate within the relationship, and more broadly in society. The three typologies are grounded in men's heterosexual intimate partner gender relations, and advance masculinity frameworks to guide future health-research, policy and practice. In addition, there are opportunities for men's mental health promotion by prompting readers' reflexivity to thoughtfully consider what they idealize, and where they map in relation to the masculine typologies featured in the current article.
Asunto(s)
Heterosexualidad , Violencia de Pareja , Masculino , Humanos , Adulto Joven , Adulto , Masculinidad , Promoción de la Salud , Relaciones InterpersonalesRESUMEN
Doxorubicin is a commonly used anthracycline chemotherapeutic agent; however, its application is limited owing to its cardiotoxicity. Current clinical treatments cannot efficiently or fully prevent doxorubicin-induced toxicity, primarily because its pathogenesis and mechanisms of action remain unknown. In this study, we established a rat model of chronic doxorubicin-induced cardiotoxicity, in which the severity of cardiac fibrosis and hydroxyproline levels increased in a time-dependent manner. Doxorubicin damaged the mitochondria and blood vessels and induced autophagy. Cells undergoing endothelial-to-mesenchymal transition (EndoMT)and those expressing endothelial cell and myofibroblast markers were simultaneously observed in vitro and in rats treated with doxorubicin. The NF-κB pathway was activated during EndoMT, andp65 and p-p65 were strongly expressed in the nucleus of endothelial cells in vitro. Taken together, these results suggest that vascular injury and cardiac fibrosis are characteristic symptoms of doxorubicin-induced cardiotoxicity. The NF-κB pathway-associated EndoMT may influence the pathogenesis of doxorubicin-induced cardiotoxicity, and the constituents of this pathway may be potential therapeutic targets to prevent the development of this condition.
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Antibióticos Antineoplásicos/toxicidad , Cardiotoxicidad/prevención & control , Doxorrubicina/toxicidad , Células Endoteliales/efectos de los fármacos , FN-kappa B/efectos de los fármacos , Transducción de Señal/efectos de los fármacos , Animales , Autofagia/efectos de los fármacos , Vasos Sanguíneos/efectos de los fármacos , Cardiotoxicidad/patología , Femenino , Fibrosis , Hidroxiprolina/metabolismo , Masculino , Mitocondrias Cardíacas/efectos de los fármacos , Miofibroblastos/efectos de los fármacos , Ratas , Ratas Sprague-Dawley , Factor de Transcripción ReIA/efectos de los fármacosRESUMEN
Malignant melanoma has a profound influence on populations around the world, with the underlying mechanisms controlling this disease yet to be fully identified. Hence, the current study aimed to investigate effects associated with VEPH1 on epithelial-mesenchymal transition (EMT), proliferation, invasion, migration and the apoptosis of human cutaneous melanoma (CM) cells through the TGF-ß signaling pathway. Microarray-based gene analysis was initially performed to screen the CM-related differentially expressed genes. The expression of VEPH1, TGF-ß signaling pathway- and EMT-related genes in CM tissues and cell lines was subsequently evaluated. Gain-of- and loss-of-function experiments were conducted to examine the effects of VEPH1 and the TGF-ß signaling pathway on the expression of EMT-related genes, cell proliferation, migration, invasion, cell cycle and apoptosis in vitro. Finally, tumor formation in nude mice was conducted. VEPH1 was lowly expressed and regulated the progression of CM with involvement in the TGF-ß signaling pathway. Human CM tissues were noted to activate the TGF-ß signaling pathway and EMT. A375 cells treated with overexpressed VEPH1 plasmids or/and TGF-ß signaling pathway inhibitor SB-431542 displayed diminished TGF-ß, SMAD4, Vimentin and N-cadherin expression while the expression of E-cadherin was elevated, accompanied by decreased cell proliferation, migration, invasion, inhibited cell cycle entry. However, si-VEPH1 or TGF-ß signaling pathway activator contributed to reverse results. Taken together, the key findings of the current study present evidence suggesting that VEPH1 protects against human CM by inhibiting the activation of the TGF-ß signaling pathway, highlighting its potential as a target for the prognosis and diagnosis of CM.
Asunto(s)
Transición Epitelial-Mesenquimal/fisiología , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Melanoma/patología , Neoplasias Cutáneas/patología , Factor de Crecimiento Transformador beta1/antagonistas & inhibidores , Adulto , Anciano , Animales , Apoptosis/fisiología , Benzamidas/farmacología , Cadherinas/biosíntesis , Línea Celular Tumoral , Movimiento Celular/fisiología , Proliferación Celular/fisiología , Dioxoles/farmacología , Femenino , Humanos , Péptidos y Proteínas de Señalización Intracelular/biosíntesis , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Persona de Mediana Edad , Invasividad Neoplásica/patología , Pronóstico , Transducción de Señal/fisiología , Proteína Smad4/biosíntesis , Vimentina/biosíntesisRESUMEN
The public health impact of Streptococcus pyogenes (group A Streptococcus, GAS) as a top 10 cause of infection-related mortality in humans contrasts with its benefit to biotechnology as the main natural source of Cas9 nuclease, the key component of the revolutionary CRISPR-Cas9 gene editing platform. Despite widespread knowledge acquired in the last decade on the molecular mechanisms by which GAS Cas9 achieves precise DNA targeting, the functions of Cas9 in the biology and pathogenesis of its native organism remain unknown. In this study, we generated an isogenic serotype M1 GAS mutant deficient in Cas9 protein and compared its behavior and phenotypes to the wild-type parent strain. Absence of Cas9 was linked to reduced GAS epithelial cell adherence, reduced growth in human whole blood ex vivo, and attenuation of virulence in a murine necrotizing skin infection model. Virulence defects of the GAS Δcas9 strain were explored through quantitative proteomic analysis, revealing a significant reduction in the abundance of key GAS virulence determinants. Similarly, deletion of cas9 affected the expression of several known virulence regulatory proteins, indicating that Cas9 impacts the global architecture of GAS gene regulation.
RESUMEN
Group A Streptococcus (GAS) is among the top ten causes of infection-related mortality in humans. M protein is the most abundant GAS surface protein, and M1 serotype GAS strains are associated with invasive infections, including necrotizing fasciitis and toxic shock syndrome. Here, we report that released, soluble M1 protein triggers programmed cell death in macrophages (MÏ). M1 served as a second signal for caspase-1-dependent NLRP3 inflammasome activation, inducing maturation and release of proinflammatory cytokine interleukin-1ß (IL-1ß) and macrophage pyroptosis. The structurally dynamic B-repeat domain of M1 was critical for inflammasome activation, which involved K+ efflux and M1 protein internalization by clathrin-mediated endocytosis. Mouse intraperitoneal challenge showed that soluble M1 was sufficient and specific for IL-1ß activation, which may represent an early warning to activate host immunity against the pathogen. Conversely, in systemic infection, hyperinflammation associated with M1-mediated pyroptosis and IL-1ß release could aggravate tissue injury.
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Antígenos Bacterianos/metabolismo , Proteínas de la Membrana Bacteriana Externa/metabolismo , Proteínas Portadoras/metabolismo , Interacciones Huésped-Patógeno/inmunología , Inflamasomas/inmunología , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Streptococcus pyogenes/inmunología , Streptococcus pyogenes/metabolismo , Animales , Apoptosis , Caspasa 1/metabolismo , Modelos Animales de Enfermedad , Endocitosis , Femenino , Humanos , Interleucina-1beta/metabolismo , Macrófagos/inmunología , Macrófagos/microbiología , Masculino , Ratones , Ratones Endogámicos C57BL , Piroptosis , Transducción de Señal , Infecciones Estreptocócicas/inmunología , Infecciones Estreptocócicas/microbiología , Streptococcus pyogenes/genética , Streptococcus pyogenes/patogenicidad , Células THP-1 , Factores de VirulenciaRESUMEN
Activation of CD4 T cells is a reaction to challenges such as microbial pathogens, cancer and toxins that defines adaptive immune responses. The roles of T cell receptor crosslinking, intracellular signaling, and transcription factor activation are well described, but the importance of post-transcriptional regulation by RNA-binding proteins (RBPs) has not been considered in depth. We describe a new model expanding and activating primary human CD4 T cells and applied this to characterizing activation-induced assembly of splicing factors centered on U2AF2. We immunoprecipitated U2AF2 to identify what mRNA transcripts were bound as a function of activation by TCR crosslinking and costimulation. In parallel, mass spectrometry revealed the proteins incorporated into the U2AF2-centered RNA/protein interactome. Molecules that retained interaction with the U2AF2 complex after RNAse treatment were designated as "central" interactome members (CIMs). Mass spectrometry also identified a second class of activation-induced proteins, "peripheral" interactome members (PIMs), that bound to the same transcripts but were not in physical association with U2AF2 or its partners. siRNA knockdown of two CIMs and two PIMs caused changes in activation marker expression, cytokine secretion, and gene expression that were unique to each protein and mapped to pathways associated with key aspects of T cell activation. While knocking down the PIM, SYNCRIP, impacts a limited but immunologically important set of U2AF2-bound transcripts, knockdown of U2AF1 significantly impairs assembly of the majority of protein and mRNA components in the activation-induced interactome. These results demonstrated that CIMs and PIMs, either directly or indirectly through RNA, assembled into activation-induced U2AF2 complexes and play roles in post-transcriptional regulation of genes related to cytokine secretion. These data suggest an additional layer of regulation mediated by the activation-induced assembly of RNA splicing interactomes that is important for understanding T cell activation.