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BACKGROUND: O-GlcNAcylation modification affects multiple physiological and pathophysiolocal functions of cells. Altered O-GlcNAcylation was reported to participate in antivirus response. Stimulator of interferon genes (STING) is an adaptor mediating DNA virus-induced innate immune response. Whether STING is able to be modified by O-GlcNAcylation and how O-GlcNAcylation affects STING-mediated anti-DNA virus response remain unknown. METHODS: Metabolomics analysis was used for detecting metabolic alterations in HSV-1 infection cells. Succinylated wheat germ agglutinin (sWGA), co-immunoprecipitation, and pull-down assay were employed for determining O-GlcNAcylation. Mutagenesis PCR was applied for the generation of STING mutants. WT and Sting1-/- C57BL/6 mice (KOCMP-72512-Sting1-B6NVA) were infected with HSV-1 and treated with O-GlcNAcylation inhibitor for validating the role of STING O-GlcNAcylation in antiviral response. RESULTS: STING was functionally activated by O-GlcNAcylation in host cells challenged with HSV-1. We demonstrated that this signaling event was initiated by virus infection-enhanced hexosamine biosynthesis pathway (HBP). HSV-1 (or viral DNA mimics) promotes glucose metabolism of host cells with a marked increase in HBP, which provides donor glucosamine for O-GlcNAcylation. STING was O-GlcNAcylated on threonine 229, which led to lysine 63-linked ubiquitination of STING and activation of antiviral immune responses. Mutation of STING T229 to alanine abrogated STING activation and reduced HSV-1 stimulated production of interferon (IFN). Application of 6-diazo-5-oxonorleucine (DON), an agent that blocks the production of UDP-GlcNAc and inhibits O-GlcNAcylation, markedly attenuated the removal of HSV-1 in wild type C57BL/6 mice, leading to an increased viral retention, elevated infiltration of inflammatory cells, and worsened tissue damages to those displayed in STING gene knockout mice. Together, our data suggest that STING is O-GlcNAcylated in HSV-1, which is crucial for an effective antiviral innate immune response. CONCLUSION: HSV-1 infection activates the generation of UDP-Glc-NAc by upregulating the HBP metabolism. Elevated UDP-Glc-NAc promotes the O-GlcNAcylation of STING, which mediates the anti-viral function of STING. Targeting O-GlcNAcylation of STING could be a useful strategy for antiviral innate immunity.
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Herpesvirus Humano 1 , Proteínas de Membrana , Animais , Camundongos , Herpesvirus Humano 1/metabolismo , Imunidade Inata , Interferons , Proteínas de Membrana/metabolismo , Camundongos Endogâmicos C57BL , Difosfato de UridinaRESUMO
Whether bone marrow regulates bone metabolism through endocrine and paracrine mechanism remains largely unknown. Here, we found that (i) myeloid cell-specific myeloid-derived growth factor (MYDGF) deficiency decreased bone mass and bone strength in young and aged mice; (ii) myeloid cell-specific MYDGF restoration prevented decreases in bone mass and bone strength in MYDGF knockout mice; moreover, myeloid cell-derived MYDGF improved the progress of bone defects healing, prevented ovariectomy (OVX)-induced bone loss and age-related osteoporosis; (iii) MYDGF inhibited osteoclastogenesis and promoted osteoblast differentiation in vivo and in vitro; and (iv) PKCß-NF-κB and MAPK1/3-STAT3 pathways were involved in the regulation of MYDGF on bone metabolism. Thus, we concluded that myeloid cell-derived MYDGF is a positive regulator of bone homeostasis by inhibiting bone resorption and promoting bone formation. MYDGF may become a potential novel therapeutic drug for osteoporosis, and bone marrow may become a potential therapeutic target for bone metabolic disorders.
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Reabsorção Óssea , Interleucinas , Osteogênese , Animais , Reabsorção Óssea/metabolismo , Reabsorção Óssea/prevenção & controle , Osso e Ossos/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Feminino , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Interleucinas/genética , Interleucinas/metabolismo , Interleucinas/farmacologia , Camundongos , Camundongos Endogâmicos C57BL , NF-kappa B/metabolismo , Osteoblastos/metabolismo , Osteogênese/genéticaRESUMO
BACKGROUND: Inflammation contributes to the pathogenesis of atherosclerosis. But little is known about the potential benefits of inflammatory cells to atherosclerosis. The aim of this study was to investigate the function of inflammatory cells/endothelium axis and determine whether and how inflammatory cell-derived MYDGF (myeloid-derived growth factor) inhibited endothelial LDL (low-density lipoprotein) transcytosis. METHODS: In in vivo experiments, both loss- and gain-of-function strategies were used to evaluate the effect of inflammatory cell-derived MYDGF on LDL transcytosis. We generated monocyte/macrophage-targeted MYDGF-null mice on an Ldlr (LDL receptor)-/- background in the loss-of-function strategy and restored the inflammatory cell-derived MYDGF by bone marrow transplantation and inflammatory cell-specific overexpression of MYDGF mice model in the gain-of-function strategy. In in vitro experiments, coculture experiments between primary mouse aortic endothelial cells and macrophages and mouse aortic endothelial cells supplemented with or without recombinant MYDGF were conducted. RESULTS: Inflammatory cell-derived MYDGF deficiency aggravated endothelial LDL transcytosis, drove LDL uptake by artery wall, and thus exacerbated atherosclerosis in vivo. Inflammatory cell-derived MYDGF restoration by bone marrow transplantation and inflammatory cell MYDGF overexpression alleviated LDL transport across the endothelium, prevented LDL accumulation in the subendothelial space, and subsequently ameliorated atherosclerosis in vivo. Furthermore, in the in vitro study, macrophages isolated from MYDGF+/+ mice and recombinant MYDGF attenuated LDL transcytosis and uptake in mouse aortic endothelial cells. Mechanistically, MYDGF inhibited MAP4K4 (mitogen-activated protein kinase kinase kinase kinase isoform 4) phosphorylation, enhanced activation of Akt (protein kinase B)-1, and diminished the FoxO (forkhead box O) 3a signaling cascade to exert protective effects of MYDGF on LDL transcytosis and atherosclerosis. CONCLUSIONS: The findings support a role for inflammatory cell-derived MYDGF served as a cross talk factor between inflammatory cells and endothelial cells that inhibits LDL transcytosis across endothelium. MYDGF may become a novel therapeutic drug for atherosclerosis, and the beneficial effects of inflammatory cell in atherosclerosis deserve further attention.
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Aterosclerose , Células Endoteliais , Camundongos , Animais , Células Endoteliais/metabolismo , Aterosclerose/genética , Aterosclerose/prevenção & controle , Aterosclerose/metabolismo , Lipoproteínas LDL/metabolismo , Receptores de LDL/genética , Receptores de LDL/metabolismo , Camundongos Knockout , Transcitose , Endotélio/metabolismoRESUMO
The source of macrophages that contribute to human liver disease remains poorly understood. The purpose of this study is to investigate the functional mechanism of peritoneal macrophages in the development of hepatic immunopathology. By performing the natural infection with the blood fluke Schistosoma japonicum (S. japonicum) and the chemically carbon tetrachloride (CCl4 )-induced liver injured mouse model, we identified the peritoneal cavity as an essential source of hepatic macrophages. Here, we show that a large number of F4/80+ macrophages was accumulated in the peritoneal cavity during liver injury. An unknown source population of macrophages, which highly expressed GATA6 that is specific to peritoneal macrophages, was found to exist in the injured livers. Peritoneal macrophage deletion by injection with clodronate-containing liposomes led to an attenuated hepatic pathology and the inflammatory microenvironment, while adoptive transfer of macrophages into the abdominal cavity, by contrast, results in restoring liver pathology. Importantly, there are set genes of monocyte chemoattractant protein (MCP)-1, -2, and -3 that are highly related to recruit GATA6+ macrophages during S. japonicum infection, while administration of bindarit, a selective inhibitor of MCPs synthesis, dramatically decreased the hepatic expression of GATA6+ macrophages and thus attenuated hepatic pathology. Furthermore, in vivo study showed that peritoneal macrophages promote hepatic immunopathology is dependent on the accumulation of regulatory T cells (Tregs) in the liver. Altogether, these data provide the first clear evidence that GATA6+ peritoneal macrophages play critical roles in both the formation of hepatic immunopathology and the accumulation of Tregs cells.
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Schistosoma japonicum , Esquistossomose Japônica , Animais , Fator de Transcrição GATA6/genética , Fator de Transcrição GATA6/metabolismo , Humanos , Fígado/metabolismo , Macrófagos/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Esquistossomose Japônica/metabolismo , Linfócitos T Reguladores/metabolismoRESUMO
Osteoarthritis (OA) is characterized by chondrocyte apoptosis and increased degradation of type II collagen. Inflammation is one of the major risk factors involved in the pathophysiology of OA. Neuregulin 4 (Nrg4) plays a protective role in a variety of low-level inflammatory diseases, such as non-alcoholic fatty liver disease, inflammatory bowel disease, or type 2 diabetes mellitus. Here we found that (1) Nrg4 deficiency aggravated the destruction and inflammation of articular cartilage and the apoptosis of chondrocytes in vivo. (2) Nrg4 restoration reversed these changes in vivo. (3) Murine recombinant Nrg4 (rNrg4) suppressed inflammation and apoptosis of chondrocytes and decreased the degradation of extracellular matrix in vitro. (4) Mechanistically, the mitogen-activated protein kinase/c-jun N-terminal kinase (MAPK/JNK) signaling pathway may be involved in the regulation of Nrg4 in the pathophysiology of OA. Therefore, we concluded that Nrg4 alleviated the progression of OA by inhibiting the inflammation, protecting against apoptosis of chondrocyte, and decreasing the degradation of extracellular matrix in a manner involving MAPK/JNK signaling.
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Apoptose , Cartilagem Articular , Condrócitos , Neurregulinas/genética , Osteoartrite , Animais , Células Cultivadas , Progressão da Doença , Inflamação , Camundongos , Osteoartrite/genéticaRESUMO
CD4+ T cells differentiate into distinct functional effector and inhibitory subsets are facilitated by distinct cytokine cues present at the time of antigen recognition. Maintaining a balance between T helper 17 (Th17) and regulatory T (Treg) cells are critical for the control of the immunopathogenesis of liver diseases. Here, by using the mouse model of helminth Schistosoma japonicum (S japonicum) infection, we show that the hepatic mRNA levels of P21-activated kinase 1 (PAK1), a key regulator of the actin cytoskeleton, adhesion and cell motility, are significantly increased and associated with the development of liver pathology during S japonicum infection. In addition, PAK1-deficient mice are prone to suppression of Th17 cell responses but increased Treg cells. Furthermore, PAK1 enhances macrophage activation through promoting IRF1 nuclear translocation in an NF-κB-dependent pathway, resulting in promoting Th17 cell differentiation through inducing IL-6 production. These findings highlight the importance of PAK1 in macrophages fate determination and suggest that PAK1/IRF1 axis-dependent immunomodulation can ameliorate certain T cell-based immune pathologies.
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Helmintíase/metabolismo , Helmintíase/parasitologia , Macrófagos/imunologia , Macrófagos/metabolismo , Células Th17/imunologia , Células Th17/metabolismo , Quinases Ativadas por p21/metabolismo , Animais , Antígenos de Helmintos/imunologia , Biomarcadores , Citocinas/metabolismo , Modelos Animais de Doenças , Imunofenotipagem , Camundongos , Esquistossomose Japônica/imunologia , Esquistossomose Japônica/metabolismo , Esquistossomose Japônica/parasitologia , Subpopulações de Linfócitos T/imunologia , Subpopulações de Linfócitos T/metabolismoRESUMO
Atrial fibrillation (AF) is the most common arrhythmia in clinic, which can cause hemodynamic changes, heart failure and stroke, and seriously affect human life and health. As a self-promoting disease, the treatment of AF can become more and more difficult with the deterioration of the disease, and the early prediction and intervention of AF is the key to curbing the deterioration of the disease. Based on this, in this study, by controlling the dose of acetylcholine, we changed the AF vulnerability of five mongrel dogs and tried to assess it by analyzing the electrophysiology of atrial epicardium under different states of sinus rhythm. Here, indices from four aspects were proposed to study the atrial activation rule. They are the variability of atrial activation rhythm, the change of the earliest atrial activation, the change of atrial activation delay and the left-right atrial dyssynchrony. By using binary logistic regression analysis, multiple indices above were transformed into the AF inducibility, which were used to classify the signals during sinus rhythm. The sensitivity, specificity and accuracy of classification reached 85.7%, 95.8% and 91.7%, respectively. As the experimental results show, the proposed method has the ability to assess the AF vulnerability of atrium, which is of great clinical significance for the early prediction and intervention of AF.
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Fibrilação Atrial , Mapeamento Epicárdico , Animais , Fibrilação Atrial/diagnóstico , Cães , Fenômenos Eletrofisiológicos , Átrios do Coração , Humanos , Acidente Vascular Cerebral/prevenção & controleRESUMO
Esophageal squamous cell carcinoma (ESCC) possesses a poor prognosis and treatment outcome. Dysregulated metabolism contributes to unrestricted growth of multiple cancers. However, abnormal metabolism, such as highly activated pentose phosphate pathway (PPP) in the progression of ESCC remains largely unknown. Herein, we report that high-mobility group AT-hook 1 (HMGA1), a structural transcriptional factor involved in chromatin remodeling, promoted the development of ESCC by upregulating the PPP. We found that HMGA1 was highly expressed in ESCC. Elevated HMGA1 promoted the malignant phenotype of ESCC cells. Conditional knockout of HMGA1 markedly reduced 4-nitroquinoline-1-oxide (4NQO)-induced esophageal tumorigenesis in mice. Through the metabolomic analysis and the validation assay, we found that HMGA1 upregulated the non-oxidative PPP. With the transcriptome sequencing, we identified that HMGA1 upregulated the expression of transketolase (TKT), which catalyzes the reversible reaction in non-oxidative PPP to exchange metabolites with glycolytic pathway. HMGA1 knockdown suppressed the PPP by downregulating TKT, resulting in the reduction of nucleotides in ESCC cells. Overexpression of HMGA1 upregulated PPP and promoted the survival of ESCC cells by activating TKT. We further characterized that HMGA1 promoted the transcription of TKT by interacting with and enhancing the binding of transcription factor SP1 to the promoter of TKT. Therapeutics targeting TKT with an inhibitor, oxythiamine, reduced HMGA1-induced ESCC cell proliferation and tumor growth. Together, in this study, we identified a new role of HMGA1 in ESCCs by upregulating TKT-mediated activation of PPP. Our results provided a new insight into the role of HMGA1/TKT/PPP in ESCC tumorigenesis and targeted therapy.
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Progressão da Doença , Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , Proteína HMGA1a , Via de Pentose Fosfato , Transcetolase , Regulação para Cima , Humanos , Animais , Transcetolase/metabolismo , Transcetolase/genética , Carcinoma de Células Escamosas do Esôfago/patologia , Carcinoma de Células Escamosas do Esôfago/genética , Carcinoma de Células Escamosas do Esôfago/metabolismo , Proteína HMGA1a/metabolismo , Proteína HMGA1a/genética , Neoplasias Esofágicas/patologia , Neoplasias Esofágicas/genética , Neoplasias Esofágicas/metabolismo , Camundongos , Regulação para Cima/genética , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica , Proliferação de Células , Camundongos Nus , Fator de Transcrição Sp1/metabolismo , Fator de Transcrição Sp1/genéticaRESUMO
Chemotherapy is a primary treatment for esophageal squamous cell carcinoma (ESCC). Resistance to chemotherapeutic drugs is an important hurdle to effective treatment. Understanding the mechanisms underlying chemotherapy resistance in ESCC is an unmet medical need to improve the survival of ESCC. Herein, we demonstrate that ferroptosis triggered by inhibiting high mobility group AT-hook 1 (HMGA1) may provide a novel opportunity to gain an effective therapeutic strategy against chemoresistance in ESCC. HMGA1 is upregulated in ESCC and works as a key driver for cisplatin (DDP) resistance in ESCC by repressing ferroptosis. Inhibition of HMGA1 enhances the sensitivity of ESCC to ferroptosis. With a transcriptome analysis and following-up assays, we demonstrated that HMGA1 upregulates the expression of solute carrier family 7 member 11 (SLC7A11), a key transporter maintaining intracellular glutathione homeostasis and inhibiting the accumulation of malondialdehyde (MDA), thereby suppressing cell ferroptosis. HMGA1 acts as a chromatin remodeling factor promoting the binding of activating transcription factor 4 (ATF4) to the promoter of SLC7A11, and hence enhancing the transcription of SLC7A11 and maintaining the redox balance. We characterized that the enhanced chemosensitivity of ESCC is primarily attributed to the increased susceptibility of ferroptosis resulting from the depletion of HMGA1. Moreover, we utilized syngeneic allograft tumor models and genetically engineered mice of HMGA1 to induce ESCC and validated that depletion of HMGA1 promotes ferroptosis and restores the sensitivity of ESCC to DDP, and hence enhances the therapeutic efficacy. Our finding uncovers a critical role of HMGA1 in the repression of ferroptosis and thus in the establishment of DDP resistance in ESCC, highlighting HMGA1-based rewiring strategies as potential approaches to overcome ESCC chemotherapy resistance. Schematic depicting that HMGA1 maintains intracellular redox homeostasis against ferroptosis by assisting ATF4 to activate SLC7A11 transcription, resulting in ESCC resistance to chemotherapy.
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Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , Ferroptose , Animais , Camundongos , Carcinoma de Células Escamosas do Esôfago/tratamento farmacológico , Carcinoma de Células Escamosas do Esôfago/genética , Neoplasias Esofágicas/tratamento farmacológico , Neoplasias Esofágicas/genética , Neoplasias Esofágicas/metabolismo , Proteína HMGA1a/genética , Resistencia a Medicamentos Antineoplásicos/genética , Ferroptose/genética , Proteína HMGA1b , Linhagem Celular TumoralRESUMO
Esophageal carcinoma is amongst the prevalent malignancies worldwide, characterized by unclear molecular classifications and varying clinical outcomes. The PI3K/AKT/mTOR signaling, one of the frequently perturbed dysregulated pathways in human malignancies, has instigated the development of various inhibitory agents targeting this pathway, but many ESCC patients exhibit intrinsic or adaptive resistance to these inhibitors. Here, we aim to explore the reasons for the insensitivity of ESCC patients to mTOR inhibitors. We assessed the sensitivity to rapamycin in various ESCC cell lines by determining their respective IC50 values and found that cells with a low level of HMGA1 were more tolerant to rapamycin. Subsequent experiments have supported this finding. Through a transcriptome sequencing, we identified a crucial downstream effector of HMGA1, FKBP12, and found that FKBP12 was necessary for HMGA1-induced cell sensitivity to rapamycin. HMGA1 interacted with ETS1, and facilitated the transcription of FKBP12. Finally, we validated this regulatory axis in in vivo experiments, where HMGA1 deficiency in transplanted tumors rendered them resistance to rapamycin. Therefore, we speculate that mTOR inhibitor therapy for individuals exhibiting a reduced level of HMGA1 or FKBP12 may not work. Conversely, individuals exhibiting an elevated level of HMGA1 or FKBP12 are more suitable candidates for mTOR inhibitor treatment.
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Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , Proteína HMGA1a , Inibidores de MTOR , Proteína Proto-Oncogênica c-ets-1 , Proteína 1A de Ligação a Tacrolimo , Animais , Humanos , Camundongos , Linhagem Celular Tumoral , Neoplasias Esofágicas/metabolismo , Neoplasias Esofágicas/tratamento farmacológico , Neoplasias Esofágicas/genética , Carcinoma de Células Escamosas do Esôfago/metabolismo , Carcinoma de Células Escamosas do Esôfago/tratamento farmacológico , Carcinoma de Células Escamosas do Esôfago/genética , Carcinoma de Células Escamosas do Esôfago/patologia , Proteína HMGA1a/metabolismo , Proteína HMGA1a/genética , Camundongos Nus , Inibidores de MTOR/farmacologia , Inibidores de MTOR/uso terapêutico , Proteína Proto-Oncogênica c-ets-1/metabolismo , Proteína Proto-Oncogênica c-ets-1/genética , Transdução de Sinais/efeitos dos fármacos , Sirolimo/farmacologia , Sirolimo/uso terapêutico , Proteína 1A de Ligação a Tacrolimo/metabolismo , Proteína 1A de Ligação a Tacrolimo/genética , Serina-Treonina Quinases TOR/metabolismoRESUMO
In this article, an integral barrier Lyapunov-function (IBLF)-based adaptive tracking controller is proposed for a class of switched nonlinear systems under the arbitrary switching rule, in which the unknown terms are approximated by radial basis function neural networks (RBFNNs). The IBLF method is used to solve the problem of state constraint. This method constrains states directly and avoids the verification of feasibility conditions. In addition, a completely unknown control gain is considered, which makes it impossible to directly apply previous existing methods. To offset the effect of the unknown control gain, the lower bound of the control gain is added into the barrier Lyapunov function, and a regulating term is introduced into the controller. The proposed control strategy realizes three control objectives: 1) all the signals in the resulting system are bounded; 2) the system output tracks the reference signal to a arbitrarily small compact set; and 3) all the constraint conditions for system states are not violated. Finally, a simulation example is used to show the effectiveness of the proposed method.
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BACKGROUND: Dermatophagoides pteronyssinus (D. pteronyssinus) is the main cause of allergic airway inflammation. As the earliest intracytoplasmic pathogen recognition receptors (PRR), NOD1 has been identified as key inflammatory mediator in NOD-like receptor (NLR) family. OBJECTIVE: Our primary aim is to elucidate whether NOD1 and its downstream regulatory proteins mediate D. pteronyssinus-induced allergic airway inflammation. METHODS: Mouse and cell models of D. pteronyssinus-induced allergic airway inflammation were established. NOD1 was inhibited in bronchial epithelium cells (BEAS-2B cells) and mice by cell transfection or application of inhibitor. The change of downstream regulatory proteins was detected by quantitative real-time PCR (qRT-PCR) and Western blot. The relative expression of inflammatory cytokines was evaluated by ELISA. RESULTS: The expression level of NOD1 and its downstream regulatory proteins increased in BEAS-2B cells and mice after treating with D. pteronyssinus extract, followed by the aggravation of inflammatory response. Moreover, inhibition of NOD1 decreased the inflammatory response, which also downregulated the expression of downstream regulatory proteins and inflammatory cytokines. CONCLUSIONS: NOD1 involves in the development of D. pteronyssinus-induced allergic airway inflammation. Inhibition of NOD1 reduces D. pteronyssinus-induced airway inflammation.
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Inflamação , NF-kappa B , Proteína Adaptadora de Sinalização NOD1 , Animais , Camundongos , Alérgenos , Citocinas/metabolismo , Células Epiteliais/metabolismo , NF-kappa B/metabolismo , Proteína Adaptadora de Sinalização NOD1/metabolismo , HumanosRESUMO
Tian et al. (Research Articles, 8 July 2022, abm2708) hypothesized that yunnanozoans are stem-group vertebrates on the basis of "cellular cartilage", "fibrillin microfibers", and "subchordal rod" associated with the branchial arches of yunnanozoans. However, we reject the presence of cellular cartilage, fibrillin, and the phylogenetic proposal of vertebrate affinities based on ultrastructure and morphology of yunnanozoans from more than 8000 specimens.
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Cartilagem , Faringe , Vertebrados , Animais , Faringe/ultraestrutura , FilogeniaRESUMO
Background: Dermatophagoides farinae (DFA) is an important species of house dust mites (HDMs) that causes allergic diseases. Previous studies have focused on allergens with protein components to explain the allergic effect of HDMs; however, there is little knowledge on the role of microRNAs (miRNAs) in the allergic effect of HDMs. This study aimed to unravel the new mechanism of dust mite sensitization from the perspective of cross-species transport of extracellular vesicles-encapsulated miRNAs from HDMs. Methods: Small RNA (sRNA) sequencing was performed to detect miRNAs expression profiles from DFA, DFA-derived exosomes and DFA culture supernatants. A quantitative fluorescent real-time PCR (qPCR) assay was used to detect miRNAs expression in dust specimens. BEAS-2B cells endocytosed exosomes were modeled in vitro to detect miRNAs from DFA and the expression of related inflammatory factors. Representative dfa-miR-276-3p and dfa-novel-miR2 were transfected into BEAS-2B cells, and then differentially expressed genes (DEGs) were analyzed by RNA sequencing. Protein-protein interaction (PPI) network analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway and Gene Ontology (GO) terms enrichment analyses were performed on the first 300 nodes of DEGs. Results: sRNA sequencing identified 42 conserved miRNAs and 66 novel miRNAs in DFA, DFA-derived exosomes, and DFA culture supernatants. A homology analysis was performed on the top 18 conserved miRNAs with high expression levels. The presence of dust mites and miRNAs from HDMs in living environment were also validated. Following uptake of DFA-derived exosomes by BEAS-2B cells, exosomes transported miRNAs from DFA to target cells and produced pro-inflammatory effects in corresponding cells. RNA sequencing identified DEGs in dfa-miR-276-3p and dfa-novel-miR2 transfected BEAS-2B cells. GO and KEGG enrichment analyses revealed the role of exosomes with cross-species transporting of DFA miRNAs in inflammatory signaling pathways, such as JAK-STAT signaling pathway, PI3K/AKT signaling pathway and IL-6-mediated signaling pathway. Conclusion: Our findings demonstrate the miRNAs expression profiles in DFA for the first time. The DFA miRNAs are delivered into living environments via exosomes, and engulfed by human bronchial epithelial cells, and cross-species regulation may contribute to inflammation-related processes.
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Exossomos , Hipersensibilidade , MicroRNAs , Animais , Humanos , MicroRNAs/genética , MicroRNAs/metabolismo , Dermatophagoides farinae/genética , Dermatophagoides farinae/metabolismo , Exossomos/genética , Exossomos/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Células Epiteliais/metabolismo , Pyroglyphidae , Inflamação/genética , Inflamação/metabolismo , Hipersensibilidade/metabolismo , Alérgenos/metabolismo , Poeira , Expressão GênicaRESUMO
Background: Emerging evidence reveals that SARS-CoV-2 possesses the capability to disrupt the gastrointestinal (GI) homeostasis, resulting in the long-term symptoms such as loss of appetite, diarrhea, gastroesophageal reflux, and nausea. In the current review, we summarized recent reports regarding the long-term effects of COVID-19 (long COVID) on the gastrointestine. Objective: To provide a narrative review of abundant clinical evidence regarding the development and management of long-term GI symptoms in COVID-19 patients. Results: Long-term persistent digestive symptoms are exhibited in a majority of long-COVID patients. SARS-CoV-2 infection of intestinal epithelial cells, cytokine storm, gut dysbiosis, therapeutic drugs, psychological factors and exacerbation of primary underlying diseases lead to long-term GI symptoms in COVID-19 patients. Interventions like probiotics, prebiotics, fecal microbiota transplantation, and antibiotics are proved to be beneficial in preserving intestinal microecological homeostasis and alleviating GI symptoms. Conclusion: Timely diagnosis and treatment of GI symptoms in long-COVID patients hold great significance as they may contribute to the mitigation of severe conditions and ultimately lead to the improvement of outcomes of the patients.
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Intestinal dysbiosis frequently occurs in abdominal radiotherapy and contributes to irradiation (IR)-induced intestinal damage and inflammation. Akkermansia muciniphila (A. muciniphila) is a recently characterized probiotic, which is critical for maintaining the dynamics of the intestinal mucus layer and preserving intestinal microbiota homeostasis. However, the role of A. muciniphila in the alleviation of radiation enteritis remains unknown. In this study, we reported that the abundance of A. muciniphila was markedly reduced in the intestines of mice exposed to abdominal IR and in the feces of patients who received abdominal radiotherapy. Abundance of A. muciniphila in feces of radiotherapy patients was negatively correlated with the duration of diarrhea in patients. Administration of A. muciniphila substantially mitigated IR-induced intestinal damage and prevented mouse death. Analyzing the metabolic products of A. muciniphila revealed that propionic acid, a short-chain fatty acid secreted by the microbe, mediated the radioprotective effect. We further demonstrated that propionic acid bound to G-protein coupled receptor 43 (GRP43) on the surface of intestinal epithelia and increased histone acetylation and hence enhanced the expression of tight junction proteins occludin and ZO-1 and elevated the level of mucins, leading to enhanced integrity of intestinal epithelial barrier and reduced radiation-induced intestinal damage. Metformin, a first-line agent for the treatment of type II diabetes, promoted intestinal epithelial barrier integrity and reduced radiation intestinal damage through increasing the abundance of A. muciniphila. Together, our results demonstrated that A. muciniphila plays a critical role in the reduction of abdominal IR-induced intestinal damage. Application of probiotics or their regulators, such as metformin, could be an effective treatment for the protection of radiation exposure-damaged intestine.
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Diabetes Mellitus Tipo 2 , Microbioma Gastrointestinal , Metformina , Humanos , Camundongos , Animais , Intestinos , Verrucomicrobia/metabolismoRESUMO
It is known that schistosome-derived antigens induce innate and adaptive immune responses that are essential for the formation of hepatic immunopathology. Here, we screened and synthesized four peptides derived from Schistosoma japonicum (S. japonicum) heat shock protein 90α (Sjp90α-1, -2, -3, and -4), which is widely expressed in adults and eggs of the genus S. japonicum and induces remarkable immune reactions. To define the antigenicity of these peptides, we stimulated splenocytes with peptides, and the results showed that only the Sjp90α-1 peptide could predominately induce the activation of dendritic cells (DCs) and macrophages as well as alter the proportion of follicular helper T (Tfh) cells. Next, CD4+ T cells were purified and cocultured with mouse bone-marrow-derived DCs (BMDCs) with or without Sjp90α-1 peptide stimulation in vitro, and the results showed that Sjp90α-1-stimulated BMDCs can significantly induce CD4+ T-cell differentiation into Tfh cells, while the direct stimulation of CD4+ T cells with Sjp90α-1 did not induce Tfh cells, indicating that the Sjp90α-1 peptide promotes Tfh cell differentiation depending on the presence of DCs. Furthermore, we selected and prepared an Sjp90α-1-peptide-based antibody and illustrated that it has excellent reactivity with the immunizing peptide and detects a single band of 29 kDa corresponding to the Sjp90α protein. The immunolocalization results showed that the protein recognized by this Sjp90α-1-peptide-based antibody is present in the mature eggs and the tegument of adults, implying that the parasite-derived peptide has a potential interaction with the host immune system. Finally, we evaluated antipeptide IgG antibodies and revealed a significantly higher level of anti-Sjp90α-1 peptide IgG antibodies in mice 3 weeks after S. japonicum infection. In conclusion, we illustrate that these synthetic peptides warrant further investigation by evaluating their antigen-specific immune response and their ability to efficiently induce Tfh cells. Moreover, they may constitute a potentially helpful method for the laboratory diagnosis of schistosomiasis japonica.
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Brown adipose tissue (BAT) activity contributes to cardiovascular health by its energy-dissipating capacity but how BAT modulates vascular function and atherosclerosis through endocrine mechanisms remains poorly understood. Here we show that BAT-derived neuregulin-4 (Nrg4) ameliorates atherosclerosis in mice. BAT-specific Nrg4 deficiency accelerates vascular inflammation and adhesion responses, endothelial dysfunction and apoptosis and atherosclerosis in male mice. BAT-specific Nrg4 restoration alleviates vascular inflammation and adhesion responses, attenuates leukocyte homing and reduces endothelial injury and atherosclerosis in male mice. In endothelial cells, Nrg4 decreases apoptosis, inflammation and adhesion responses induced by oxidized low-density lipoprotein. Mechanistically, protein kinase B (Akt)-nuclear factor-κB signaling is involved in the beneficial effects of Nrg4 on the endothelium. Taken together, the results reveal Nrg4 as a potential cross-talk factor between BAT and arteries that may serve as a target for atherosclerosis.
Assuntos
Tecido Adiposo Marrom , Aterosclerose , Neurregulinas , Animais , Masculino , Camundongos , Tecido Adiposo Marrom/metabolismo , Aterosclerose/metabolismo , Células Endoteliais/metabolismo , Endotélio , Inflamação/metabolismo , Neurregulinas/metabolismoRESUMO
Deficiency in T cell-mediated adaptive immunity, such as low CD8+ T cell infiltration, inhibits the immune surveillance, promotes malignant transformation, and facilitates tumor growth. Microbiota dysbiosis diminishes the immune system and contributes to the occurrence of cancer. However, the impact of oral dysbiosis on the occurrence and molecular mechanisms of oropharyngeal cancer (OPC) remains largely unknown. In the current study, we used 4-nitroquinoline-1-oxide (4NQO) to mimic tobacco-related carcinogenesis to generate a murine OPC model and determine the role of microbiota changes in OPC tumorigenesis. Our results showed that the oral flora composition of mice was deregulated during the tumorigenesis of OPC. The abundance of Streptococcus, Veillonella, Muribacter, Rodentibacter, and Gemella was increased, whereas the dominant genus Lactobacillus was gradually decreased with disease progression. We further demonstrated that infiltration of CD8+ T lymphocytes was markedly reduced due to the reduction of Lactobacillus. Supplementation of Lactobacillus increased the infiltration of CD8+ T cells, promoted the expression of IFN-γ and granzyme B, and lessened the OPC progression. Analyzing the metabolites of the Lactobacillus, we demonstrated that Lactobacillus enhanced the anti-tumor immune response by producing acetate in OPC development. Administration of acetate to mice could increase the expression of IFN-γ and IFN-γ-inducible chemokines in tumor tissues by activating GPR43 to promote the infiltration of CD8+ T lymphocytes and substantially delay the development of OPC. Together, our data suggest that dysbiosis of oral microbiota promotes the tumorigenesis of OPC through downregulation of cytotoxic T lymphocytes. Lactobacillus and its metabolite acetate improve the tumor microenvironment, which could be applied in the treatment of OPC.
RESUMO
Abdominal irradiation (IR) destroys the intestinal mucosal barrier, leading to severe intestinal infection. There is an urgent need to find safe and effective treatments to reduce IR-induced intestinal injury. In this study, we reported that metformin protected mice from abdominal IR-induced intestinal injury by improving the composition and diversity of intestinal flora. The elimination of intestinal microbiota (Abx) abrogated the protective effects of metformin on irradiated mice. We further characterized that treatment of metformin increased the murine intestinal abundance of Lactobacillus, which mediated the radioprotective effect. The administration of Lactobacillus or fecal microbiota transplantation (FMT) into Abx mice considerably lessened IR-induced intestinal damage and restored the radioprotective function of metformin in Abx mice. In addition, applying the murine intestinal organoid model, we demonstrated that IR inhibited the formation of intestinal organoids, and metformin alone bore no protective effect on organoids after IR. However, a combination of metformin and Lactobacillus or Lactobacillus alone displayed a strong radioprotection on the organoid formation. We demonstrated that metformin/Lactobacillus activated the farnesoid X receptor (FXR) signaling in intestinal epithelial cells and hence upregulated tight junction proteins and mucins in intestinal epithelia, increased the number of goblet cells, and augmented the mucus layer thickness to maintain the integrity of intestinal epithelial barrier, which eventually contributed to reduced radiation intestinal injury. In addition, we found that Lactobacillus abundance was significantly increased in the intestine of patients receiving metformin while undergoing abdominal radiotherapy and the abundance was negatively correlated with the diarrhea duration of patients. In conclusion, our results demonstrate that metformin possesses a protective effect on IR-induced intestinal injury by upregulating the abundance of Lactobacillus in the intestine.