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The histone variant macroH2A is generally linked to transcriptionally inactive chromatin, but how macroH2A regulates chromatin structure and functions in the transcriptional process remains elusive. This study reveals that while the integration of human macroH2A1.2 into nucleosomes does not affect their stability or folding dynamics, it notably hinders the maintenance of facilitates chromatin transcription's (FACT's) function. We show that FACT effectively diminishes the stability of macroH2A1.2-nucleosomes and expedites their depletion subsequent to the initial unfolding process. Furthermore, we identify the residue S139 in macroH2A1.2 as a critical switch to modulate FACT's function in nucleosome maintenance. Genome-wide analyses demonstrate that FACT-mediated depletion of macroH2A-nucleosomes allows the correct localization of macroH2A, while the S139 mutation reshapes macroH2A distribution and influences stimulation-induced transcription and cellular response in macrophages. Our findings provide mechanistic insights into the intricate interplay between macroH2A and FACT at the nucleosome level and elucidate their collective role in transcriptional regulation and immune response of macrophages.
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In the version of this article initially published, the accession code for the RNA-seq data set deposited in the NCBI public repository Sequence Read Archive was missing from the 'Data availability' subsection of the Methods section. The accession code is SRP125477.
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Semiconducting graphene plays an important part in graphene nanoelectronics because of the lack of an intrinsic bandgap in graphene1. In the past two decades, attempts to modify the bandgap either by quantum confinement or by chemical functionalization failed to produce viable semiconducting graphene. Here we demonstrate that semiconducting epigraphene (SEG) on single-crystal silicon carbide substrates has a band gap of 0.6 eV and room temperature mobilities exceeding 5,000 cm2 V-1 s-1, which is 10 times larger than that of silicon and 20 times larger than that of the other two-dimensional semiconductors. It is well known that when silicon evaporates from silicon carbide crystal surfaces, the carbon-rich surface crystallizes to produce graphene multilayers2. The first graphitic layer to form on the silicon-terminated face of SiC is an insulating epigraphene layer that is partially covalently bonded to the SiC surface3. Spectroscopic measurements of this buffer layer4 demonstrated semiconducting signatures4, but the mobilities of this layer were limited because of disorder5. Here we demonstrate a quasi-equilibrium annealing method that produces SEG (that is, a well-ordered buffer layer) on macroscopic atomically flat terraces. The SEG lattice is aligned with the SiC substrate. It is chemically, mechanically and thermally robust and can be patterned and seamlessly connected to semimetallic epigraphene using conventional semiconductor fabrication techniques. These essential properties make SEG suitable for nanoelectronics.
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The hygiene hypothesis postulates that the recent increase in allergic diseases such as asthma and hay fever observed in Western countries is linked to reduced exposure to childhood infections. Here we investigated how infection with a gammaherpesvirus affected the subsequent development of allergic asthma. We found that murid herpesvirus 4 (MuHV-4) inhibited the development of house dust mite (HDM)-induced experimental asthma by modulating lung innate immune cells. Specifically, infection with MuHV-4 caused the replacement of resident alveolar macrophages (AMs) by monocytes with regulatory functions. Monocyte-derived AMs blocked the ability of dendritic cells to trigger a HDM-specific response by the TH2 subset of helper T cells. Our results indicate that replacement of embryonic AMs by regulatory monocytes is a major mechanism underlying the long-term training of lung immunity after infection.
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Asma/terapia , Macrófagos Alveolares/imunologia , Monócitos/imunologia , Pyroglyphidae/imunologia , Rhadinovirus/imunologia , Células Th2/imunologia , Transferência Adotiva , Animais , Asma/imunologia , Linhagem Celular , Cricetinae , Células Dendríticas/imunologia , Feminino , Infecções por Herpesviridae/imunologia , Infecções por Herpesviridae/virologia , Macrófagos Alveolares/citologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Knockout , Células Th2/transplanteRESUMO
This article provides an in-depth review of computational methods for predicting transcriptional regulators (TRs) with query gene sets. Identification of TRs is of utmost importance in many biological applications, including but not limited to elucidating biological development mechanisms, identifying key disease genes, and predicting therapeutic targets. Various computational methods based on next-generation sequencing (NGS) data have been developed in the past decade, yet no systematic evaluation of NGS-based methods has been offered. We classified these methods into two categories based on shared characteristics, namely library-based and region-based methods. We further conducted benchmark studies to evaluate the accuracy, sensitivity, coverage, and usability of NGS-based methods with molecular experimental datasets. Results show that BART, ChIP-Atlas, and Lisa have relatively better performance. Besides, we point out the limitations of NGS-based methods and explore potential directions for further improvement.
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Biologia Computacional , Sequenciamento de Nucleotídeos em Larga Escala , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Biologia Computacional/métodos , Humanos , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Regulação da Expressão GênicaRESUMO
Living in a microbe-rich environment reduces the risk of developing asthma. Exposure of humans or mice to unmethylated CpG DNA (CpG) from bacteria reproduces these protective effects, suggesting a major contribution of CpG to microbe-induced asthma resistance. However, how CpG confers protection remains elusive. We found that exposure to CpG expanded regulatory lung interstitial macrophages (IMs) from monocytes infiltrating the lung or mobilized from the spleen. Trafficking of IM precursors to the lung was independent of CCR2, a chemokine receptor required for monocyte mobilization from the bone marrow. Using a mouse model of allergic airway inflammation, we found that adoptive transfer of IMs isolated from CpG-treated mice recapitulated the protective effects of CpG when administered before allergen sensitization or challenge. IM-mediated protection was dependent on IL-10, given that Il10-/- CpG-induced IMs lacked regulatory effects. Thus, the expansion of regulatory lung IMs upon exposure to CpG might underlie the reduced risk of asthma development associated with a microbe-rich environment.
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Quimiotaxia de Leucócito/imunologia , DNA Bacteriano/imunologia , Hipersensibilidade/imunologia , Macrófagos Alveolares/imunologia , Hipersensibilidade Respiratória/imunologia , Animais , Modelos Animais de Doenças , Citometria de Fluxo , Ativação de Macrófagos/imunologia , Macrófagos/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Oligodesoxirribonucleotídeos/imunologia , Baço/imunologiaRESUMO
The human FACT (facilitates chromatin transcription) complex, composed of two subunits SPT16 (Suppressor of Ty 16) and SSRP1 (Structure-specific recognition protein-1), plays essential roles in nucleosome remodeling. However, the molecular mechanism of FACT reorganizing the nucleosome still remains elusive. In this study, we demonstrate that FACT displays dual functions in destabilizing the nucleosome and maintaining the original histones and nucleosome integrity at the single-nucleosome level. We found that the subunit SSRP1 is responsible for maintenance of nucleosome integrity by holding the H3/H4 tetramer on DNA and promoting the deposition of the H2A/H2B dimer onto the nucleosome. In contrast, the large subunit SPT16 destabilizes the nucleosome structure by displacing the H2A/H2B dimers. Our findings provide mechanistic insights by which the two subunits of FACT coordinate with each other to fulfill its functions and suggest that FACT may play essential roles in preserving the original histones with epigenetic identity during transcription or DNA replication.
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Proteínas de Ligação a DNA/metabolismo , Proteínas de Grupo de Alta Mobilidade/metabolismo , Nucleossomos/metabolismo , Fatores de Elongação da Transcrição/metabolismo , Animais , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Cromatina/metabolismo , DNA/metabolismo , Replicação do DNA , Proteínas de Ligação a DNA/genética , Proteínas de Grupo de Alta Mobilidade/genética , Histonas/metabolismo , Humanos , Modelos Moleculares , Nucleossomos/genética , Ligação Proteica , Multimerização Proteica , Proteínas de Saccharomyces cerevisiae/metabolismo , Células Sf9 , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Fatores de Elongação da Transcrição/genéticaRESUMO
Fatty acid oxidation (FAO) is crucial for cells to overcome metabolic stress by providing ATP and NADPH. However, the mechanism by which FAO is regulated in tumors remains elusive. Here we show that Nur77 is required for the metabolic adaptation of melanoma cells by protecting FAO. Glucose deprivation activates ERK2 to phosphorylate and induce Nur77 translocation to the mitochondria, where Nur77 binds to TPß, a rate-limiting enzyme in FAO. Although TPß activity is normally inhibited by oxidation under glucose deprivation, the Nur77-TPß association results in Nur77 self-sacrifice to protect TPß from oxidation. FAO is therefore able to maintain NADPH and ATP levels and prevent ROS increase and cell death. The Nur77-TPß interaction further promotes melanoma metastasis by facilitating circulating melanoma cell survival. This study demonstrates a novel regulatory function of Nur77 with linkage of the FAO-NADPH-ROS pathway during metabolic stress, suggesting Nur77 as a potential therapeutic target in melanoma.
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Melanoma/metabolismo , Membro 1 do Grupo A da Subfamília 4 de Receptores Nucleares/metabolismo , Animais , Sobrevivência Celular/fisiologia , Ácidos Graxos/metabolismo , Glucose/metabolismo , Células HEK293 , Humanos , Metabolismo dos Lipídeos , Melanoma/patologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Mitocôndrias/metabolismo , Subunidade beta da Proteína Mitocondrial Trifuncional/metabolismo , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Estresse Oxidativo/fisiologia , Espécies Reativas de Oxigênio/metabolismoRESUMO
Inhibition of host DNA damage response (DDR) is a common mechanism used by viruses to manipulate host cellular machinery and orchestrate viral life cycles. Epstein-Barr virus tegument protein BKRF4 associates with cellular chromatin to suppress host DDR signaling, but the underlying mechanism remains elusive. Here, we identify a BKRF4 histone binding domain (residues 15-102, termed BKRF4-HBD) that can accumulate at the DNA damage sites to disrupt 53BP1 foci formation. The high-resolution structure of the BKRF4-HBD in complex with a human H2A-H2B dimer shows that BKRF4-HBD interacts with the H2A-H2B dimer via the N-terminal region (NTR), the DWP motif (residues 80-86 containing D81, W84, P86), and the C-terminal region (CTR). The "triple-anchor" binding mode confers BKRF4-HBD the ability to associate with the partially unfolded nucleosomes, promoting the nucleosome disassembly. Importantly, disrupting the BKRF4-H2A-H2B interaction impairs the binding between BKRF4-HBD and nucleosome in vitro and inhibits the recruitment of BKRF4-HBD to DNA breaks in vivo. Together, our study reveals the structural basis of BKRF4 bindings to the partially unfolded nucleosome and elucidates an unconventional mechanism of host DDR signal attenuation.
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Infecções por Vírus Epstein-Barr , Herpesvirus Humano 4 , Interações Hospedeiro-Patógeno , Nucleossomos , Proteínas Virais , Infecções por Vírus Epstein-Barr/metabolismo , Infecções por Vírus Epstein-Barr/virologia , Herpesvirus Humano 4/genética , Herpesvirus Humano 4/metabolismo , Histonas/metabolismo , Humanos , Nucleossomos/metabolismo , Nucleossomos/virologia , Ligação Proteica , Proteínas Virais/genética , Proteínas Virais/metabolismoRESUMO
BACKGROUND: The mechanism by which proton pump inhibitors (PPIs) alter gut microbiota remains to be elucidated. We aimed to learn whether PPI induced gut microbiota alterations by promoting oral microbial translocation. METHODS: Healthy adult volunteers were randomly assigned: PP group (n=8, 40 mg esomeprazole daily for seven days) and PM group (n=8, 40 mg esomeprazole along with chlorhexidine mouthwash after each meal for seven days). Fecal and saliva samples were analysed using 16S ribosomal RNA sequencing. Mouse models were introduced to confirm the findings in vivo, while the effect of pH on oral bacteria proliferation activity was investigated in vitro. RESULTS: Taxon-based analysis indicated that PPI administration increased Streptococcus abundance in gut microbiota (P<0.001), and the increased species of Streptococcus were found to be from the oral site or oral/nasal sites, in which Streptococcus anginosus was identified as the significantly changed species (P<0.004). Microbial source tracker revealed that PPI significantly increased the contribution of oral bacteria to gut microbiota (P=0.026), and no significant difference was found in PM group (P=0.467). Compared to the baseline, there was a 42-fold increase in gut abundance of Streptococcus anginosus in PP group (P=0.002), and the times decreased to 16-fold in PM group (P=0.029). Mouse models showed that combination of PPI and Streptococcus anginosus significantly increased the gut abundance of Streptococcus anginosus compared with using PPI or Streptococcus anginosus only. Furthermore, Streptococcus anginosus cannot survive in vitro at a pH lower than 5. CONCLUSIONS: PPIs altered gut microbiota by promoting oral-originated Streptococcus translocation into gut.
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Esomeprazol , Fezes , Microbioma Gastrointestinal , Inibidores da Bomba de Prótons , Saliva , Adulto , Animais , Feminino , Humanos , Masculino , Camundongos , Adulto Jovem , Translocação Bacteriana/efeitos dos fármacos , Clorexidina/farmacologia , Esomeprazol/farmacologia , Fezes/microbiologia , Microbioma Gastrointestinal/efeitos dos fármacos , Voluntários Saudáveis , Concentração de Íons de Hidrogênio , Boca/microbiologia , Antissépticos Bucais/farmacologia , Estudos Prospectivos , Inibidores da Bomba de Prótons/farmacologia , RNA Ribossômico 16S , Saliva/microbiologia , Streptococcus anginosus/efeitos dos fármacos , Streptococcus anginosus/isolamento & purificaçãoRESUMO
Aprotic lithium-oxygen (Li-O2) batteries are considered to be a promising alternative option to lithium-ion batteries for high gravimetric energy storage devices. However, the sluggish electrochemical kinetics, the passivation, and the structural damage to the cathode caused by the solid discharge products have greatly hindered the practical application of Li-O2 batteries. Herein, the nonsolid-state discharge products of the off-stoichiometric Li1-xO2 in the electrolyte solutions are achieved by iridium (Ir) single-atom-based porous organic polymers (termed as Ir/AP-POP) as a homogeneous, soluble electrocatalyst for Li-O2 batteries. In particular, the numerous atomic active sites act as the main nucleation sites of O2-related discharge reactions, which are favorable to interacting with O2-/LiO2 intermediates in the electrolyte solutions, owing to the highly similar lattice-matching effect between the in situ-formed Ir3Li and LiO2, achieving a nonsolid LiO2 as the final discharge product in the electrolyte solutions for Li-O2 batteries. Consequently, the Li-O2 battery with a soluble Ir/AP-POP electrocatalyst exhibits an ultrahigh discharge capacity of 12.8 mAh, an ultralow overpotential of 0.03 V, and a long cyclic life of 700 h with the carbon cloth cathode. The manipulation of nonsolid discharge products in aprotic Li-O2 batteries breaks the traditional growth mode of Li2O2, bringing Li-O2 batteries closer to being a viable technology.
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It is generally recognized that tumor cells proliferate more rapidly than normal cells. Due to such an abnormally rapid proliferation rate, cancer cells constantly encounter the limits of insufficient oxygen and nutrient supplies. To satisfy their growth needs and resist adverse environmental events, tumor cells modify the metabolic pathways to produce both extra energies and substances required for rapid growth. Realizing the metabolic characters special for tumor cells will be helpful for eliminating them during therapy. Cell death is a hot topic of long-term study and targeting cell death is one of the most effective ways to repress tumor growth. Many studies have successfully demonstrated that metabolism is inextricably linked to cell death of cancer cells. Here we summarize the recently identified metabolic characters that specifically impact on different types of cell deaths and discuss their roles in tumorigenesis.
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Carcinogênese , Neoplasias , Humanos , Transformação Celular Neoplásica/genética , Morte Celular , Nutrientes , Oxigênio , ApoptoseRESUMO
R-loops are stable chromatin structures comprising a DNA:RNA hybrid and a displaced single-stranded DNA. R-loops have been implicated in gene expression and chromatin structure, as well as in replication blocks and genome instability. Here, we conducted a genome-wide identification of R-loops and identified more than 700,000 R-loop peaks in the maize (Zea mays) genome. We found that sense R-loops were mainly enriched in promoters and transcription termination sites and relatively less enriched in gene bodies, which is different from the main gene-body localization of sense R-loops in Arabidopsis and Oryza sativa At the chromosome scale, maize R-loops were enriched in pericentromeric heterochromatin regions, and a significant portion of R-loops were derived from transposable elements. In centromeres, R-loops preferentially formed within the binding regions of the centromere-specific histone CENH3, and centromeric retrotransposons were strongly associated with R-loop formation. Furthermore, centromeric retrotransposon R-loops were observed by applying the single-molecule imaging technique of atomic force microscopy. These findings elucidate the fundamental character of R-loops in the maize genome and reveal the potential role of R-loops in centromeres.
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Estruturas R-Loop , Zea mays , Centrômero/genética , Mapeamento Cromossômico , Histonas/genética , Histonas/metabolismo , Zea mays/genética , Zea mays/metabolismoRESUMO
BACKGROUND: Intrahepatic cholangiocarcinoma (ICC) constitutes a group of heterogeneous malignancies within the liver. We sought to subtype ICC based on anatomical origin of tumors, as well as propose modifications of the current classification system. METHODS: Patients undergoing curative-intent resection for ICC, hilar cholangiocarcinoma (CCA), or hepatocellular carcinoma (HCC) were identified from three international multi-institutional consortia of databases. Clinicopathological characteristics and survival outcomes were assessed. RESULTS: Among 1264 patients with ICC, 1066 (84.3%) were classified as ICC-peripheral subtype, whereas 198 (15.7%) were categorized as ICC-perihilar subtype. Compared with ICC-peripheral subtype, ICC-perihilar subtype was more often associated with aggressive tumor characteristics, including a higher incidence of nodal metastasis, macro- and microvascular invasion, perineural invasion, as well as worse overall survival (OS) (median: ICC-perihilar 19.8 vs. ICC-peripheral 37.1 months; p < 0.001) and disease-free survival (DFS) (median: ICC-perihilar 12.8 vs. ICC-peripheral 15.2 months; p = 0.019). ICC-perihilar subtype and hilar CCA had comparable OS (19.8 vs. 21.4 months; p = 0.581) and DFS (12.8 vs. 16.8 months; p = 0.140). ICC-peripheral subtype tumors were associated with more advanced tumor features, as well as worse survival outcomes versus HCC (OS, median: ICC-peripheral 37.1 vs. HCC 74.3 months; p < 0.001; DFS, median: ICC-peripheral 15.2 vs. HCC 45.5 months; p < 0.001). CONCLUSIONS: ICC should be classified as ICC-perihilar and ICC-peripheral subtype based on distinct clinicopathological features and survival outcomes. ICC-perihilar subtype behaved more like carcinoma of the bile duct (i.e., hilar CCA), whereas ICC-peripheral subtype had features and a prognosis more akin to a primary liver malignancy.
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Neoplasias dos Ductos Biliares , Carcinoma Hepatocelular , Colangiocarcinoma , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/cirurgia , Neoplasias Hepáticas/patologia , Colangiocarcinoma/patologia , Prognóstico , Neoplasias dos Ductos Biliares/patologia , Ductos Biliares Intra-Hepáticos/patologiaRESUMO
We found that in regenerative erythropoiesis, the erythroid progenitor landscape is reshaped, and a previously undescribed progenitor population with colony-forming unit-erythroid (CFU-E) activity (stress CFU-E [sCFU-E]) is expanded markedly to restore the erythron. sCFU-E cells are targets of erythropoietin (Epo), and sCFU-E expansion requires signaling from the Epo receptor (EpoR) cytoplasmic tyrosines. Molecularly, Epo promotes sCFU-E expansion via JAK2- and STAT5-dependent expression of IRS2, thus engaging the progrowth signaling from the IGF1 receptor (IGF1R). Inhibition of IGF1R and IRS2 signaling impairs sCFU-E cell growth, whereas exogenous IRS2 expression rescues cell growth in sCFU-E expressing truncated EpoR-lacking cytoplasmic tyrosines. This sCFU-E pathway is the major pathway involved in erythrocytosis driven by the oncogenic JAK2 mutant JAK2(V617F) in myeloproliferative neoplasm. Inability to expand sCFU-E cells by truncated EpoR protects against JAK2(V617F)-driven erythrocytosis. In samples from patients with myeloproliferative neoplasm, the number of sCFU-E-like cells increases, and inhibition of IGR1R and IRS2 signaling blocks Epo-hypersensitive erythroid cell colony formation. In summary, we identified a new stress-specific erythroid progenitor cell population that links regenerative erythropoiesis to pathogenic erythrocytosis.
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Eritropoetina , Transtornos Mieloproliferativos , Neoplasias , Policitemia , Humanos , Eritropoese/fisiologia , Receptores da Eritropoetina/genética , Receptores da Eritropoetina/metabolismo , Policitemia/metabolismo , Eritropoetina/metabolismo , Transtornos Mieloproliferativos/metabolismo , Células Precursoras Eritroides/metabolismo , Neoplasias/metabolismo , Receptor IGF Tipo 1/metabolismoRESUMO
OBJECTIVES: The emergence of carbapenem-resistant Pseudomonas putida (CRPP) has raised public awareness. This study investigated two strains from the Pseudomonas putida group that were resistant to carbapenem, tigecycline, and aztreonam-avibactam (ATM-AVI), with a focus on their microbial and genomic characteristics. METHODS: We assessed the antibiotic resistance profile using broth dilution, disk diffusion, and E-test methods. Efflux pump phenotype testing and real-time quantitative PCR were employed to evaluate efflux pump activity in tigecycline resistance, while polymerase chain reaction was utilized to detect common carbapenem genes. Additionally, whole-genome sequencing was performed to analyze genomic characteristics. The transferability of blaIMP-1 and blaAFM-4 was assessed through a conjugation experiment. Furthermore, growth kinetics and biofilm formation were examined using growth curves and crystal violet staining. RESULTS: Both strains demonstrated resistance to carbapenem, tigecycline, and ATM-AVI. Notably, NMP can restore sensitivity to tigecycline. Subsequent analysis revealed that they co-produced blaIMP-1, blaAFM-4, tmexCD-toprJ, and blaOXA-1041, belonging to a novel sequence type ST268. Although they were closely related on the phylogenetic tree, they exhibited different levels of virulence. Genetic environment analysis indicated variations compared to prior studies, particularly regarding the blaIMP-1 and blaAFM-4 genes, which showed limited horizontal transferability. Moreover, it was observed that temperature exerted a specific influence on their biological factors. CONCLUSION: We initially identified two P. putida ST268 strains co-producing blaIMP-1, blaAFM-4, blaOXA-1041, and tmexCD-toprJ. The resistance to tigecycline and ATM-AVI can be attributed to the presence of multiple drug resistance determinants. These findings underscore the significance of P. putida as a reservoir for novel antibiotic resistance genes. Therefore, it is imperative to develop alternative antibiotic therapies and establish effective monitoring of bacterial resistance.
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Antibacterianos , Compostos Azabicíclicos , Aztreonam , Testes de Sensibilidade Microbiana , Pseudomonas putida , Tigeciclina , beta-Lactamases , Pseudomonas putida/genética , Pseudomonas putida/efeitos dos fármacos , Tigeciclina/farmacologia , Antibacterianos/farmacologia , China , Aztreonam/farmacologia , Compostos Azabicíclicos/farmacologia , beta-Lactamases/genética , beta-Lactamases/metabolismo , Farmacorresistência Bacteriana Múltipla/genética , Sequenciamento Completo do Genoma , Humanos , Combinação de Medicamentos , Biofilmes/efeitos dos fármacos , Biofilmes/crescimento & desenvolvimento , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Infecções por Pseudomonas/microbiologia , Carbapenêmicos/farmacologiaRESUMO
Exposure to particulate matter (PM10) can induce respiratory diseases that are closely related to bronchial hyperresponsiveness. However, the involved mechanism remains to be fully elucidated. This study aimed to demonstrate the effects of PM10 on the acetylcholine muscarinic 3 receptor (CHRM3) expression and the role of the ERK1/2 pathway in rat bronchial smooth muscle. A whole-body PM10 exposure system was used to stimulate bronchial hyperresponsiveness in rats for 2 and 4 months, accompanied by MEK1/2 inhibitor U0126 injection. The whole-body plethysmography system and myography were used to detect the pulmonary and bronchoconstrictor function, respectively. The mRNA and protein levels were determined by Western blotting, qPCR, and immunofluorescence. Enzyme-linked immunosorbent assay was used to detect the inflammatory cytokines. Compared with the filtered air group, 4 months of PM10 exposure significantly increased CHRM3-mediated pulmonary function and bronchial constriction, elevated CHRM3 mRNA and protein expression levels on bronchial smooth muscle, then induced bronchial hyperreactivity. Additionally, 4 months of PM10 exposure caused an increase in ERK1/2 phosphorylation and increased the secretion of inflammatory factors in bronchoalveolar lavage fluid. Treatment with the MEK1/2 inhibitor, U0126 inhibited the PM10 exposure-induced phosphorylation of the ERK1/2 pathway, thereby reducing the PM10 exposure-induced upregulation of CHRM3 in bronchial smooth muscle and CHRM3-mediated bronchoconstriction. U0126 could rescue PM10 exposure-induced pathological changes in the bronchus. In conclusion, PM10 exposure can induce bronchial hyperresponsiveness in rats by upregulating CHRM3, and the ERK1/2 pathway may be involved in this process. These findings could reveal a potential therapeutic target for air pollution induced respiratory diseases.
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Hiper-Reatividade Brônquica , Material Particulado , Receptor Muscarínico M3 , Animais , Hiper-Reatividade Brônquica/induzido quimicamente , Hiper-Reatividade Brônquica/fisiopatologia , Hiper-Reatividade Brônquica/metabolismo , Masculino , Material Particulado/toxicidade , Receptor Muscarínico M3/metabolismo , Receptor Muscarínico M3/genética , Ratos , Regulação para Cima/efeitos dos fármacos , Brônquios/efeitos dos fármacos , Brônquios/metabolismo , Brônquios/patologia , Ratos Sprague-Dawley , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Músculo Liso/efeitos dos fármacos , Músculo Liso/metabolismo , Broncoconstrição/efeitos dos fármacos , Citocinas/metabolismo , Citocinas/genética , Butadienos , NitrilasRESUMO
OBJECTIVE: To explore the clinical and imaging features of nasopharyngeal cancer (NPC) complicated by acute carotid blowout syndrome (CBS), analyze the risk factors for CBS, and improve diagnostic vigilance for early intervention. METHODS: This retrospective review was conducted between January 2003 and May 2023. Altogether, 49 patients with post-irradiation NPC with CBS and 49 patients without CBS as control group were enrolled. The condition of the patients when CBS occurred was reviewed. Patient characteristics of the CBS and control groups were compared, and binary logistic regression analysis was performed to identify risk factors for CBS. RESULTS: All patients in the CBS group were conscious, and 41 patients had a Karnofsky performance assessment scale score of ≥â¯70. After interventional therapy, 43 patients survived (the mean survival time of patients after CBS was 3.2⯱ 2.1 years). Compared with the control group, the CBS group had a higher incidence of sphenoid sinusitis (81% vs. 52.4%), osteonecrosis (82.9% vs. 51.2%), artery exposure (29.3% vs. 4.9%), and internal carotid artery injury (61% vs. 29.3%). Osteonecrosis and artery exposure were selected as important risk factor for CBS, with p-values of 0.016 and 0.031, respectively. CONCLUSION: CBS is an important factor that affects the survival of patients with NPC. If internal carotid artery injury, artery exposure, sphenoid sinusitis, and osteonecrosis are present, especially the latter two signs, the possibility of CBS should be considered.
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Sepsis-induced cardiomyopathy (SIC), caused by a dysregulated host response to infection, is a major contributor to high mortality. Angiotensin-converting enzyme 2 (ACE2), a crucial component of the renin-angiotensin system (RAS), has protective effects against several cardiovascular diseases, such as myocardial infarction and heart failure. However, the role of ACE2 in the pathogenesis of SIC and underlying mechanisms remain unknown. The present study was designed to examine the effects of ACE2 activation or inhibition on SIC in C57BL/6 mice. The ACE2 activator diminazene aceturate (DIZE) and ACE2 inhibitor MLN-4760 were applied for treatment. Myocardial function, inflammatory response, oxidative stress, apoptosis and mitochondrial biogenesis were investigated. Major assays were echocardiography, H&E staining, immunofluorescence staining, DHE staining, TUNEL staining, Western blot, qPCR analysis, ELISA and corresponding kits. We confirmed that ACE2 was markedly downregulated in septic heart tissues. Pharmacological activation of ACE2 by DIZE ameliorated cecal ligation puncture (CLP)-induced mortality, cardiac dysfunction, inflammatory response, oxidative stress and the cardiomyocyte apoptosis by promoting MasR-Sirt1-mediated mitochondrial biogenesis. In contrast, SIC was aggravated via inhibiting MasR-Sirt1-mediated mitochondrial biogenesis by the use of ACE2 inhibitor MLN-4760. Consequently, activation of ACE2 may protect against SIC by promoting MasR-Sirt1-mediated mitochondrial biogenesis.
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Cardiomiopatias , Sepse , Animais , Camundongos , Enzima de Conversão de Angiotensina 2 , Cardiomiopatias/tratamento farmacológico , Cardiomiopatias/etiologia , Camundongos Endogâmicos C57BL , Biogênese de Organelas , Peptidil Dipeptidase A , Sepse/complicações , Sepse/tratamento farmacológico , Sirtuína 1RESUMO
BACKGROUND: Bisphenol A (BPA) levels are high in women with polycystic ovary syndrome (PCOS). The mechanism by which BPA induces abnormal glucose metabolism in PCOS patients is largely unknown. METHODS: Serum and urine samples were collected from women with and without PCOS (control) at the reproductive medicine center with informed consent. Non-PCOS patients who received in vitro fertilization were recruited for collection of ovarian follicular fluid and granular cells. Wild-type C57BL/6 and AhR -/- mice were used to verify the effects of BPA on PCOS. Real-time PCR, western blotting, and ELISA were conducted to analyze the function of BPA. Chip-qPCR verified the role of AhR in GLUT4 transcription. Flow cytometry was performed to determine glucose uptake. RESULTS: A positive correlation was observed between BPA concentration and serum BPA levels in PCOS patients. BPA aggravated the changes in PCOS with abnormal glucose metabolism, impaired fertility, and increased body fat. Mechanistically, we showed that BPA activated AhR and led to decreased glucose transport via GLUT4 downregulation in ovarian granular cells. Therefore, the use of inhibitors or knockout of AhR could effectively rescue BPA-induced metabolic disorders in PCOS mice. CONCLUSIONS: Our results revealed that BPA suppressed GLUT4 expression and induced abnormal glucose metabolism by activating AhR, causing insulin resistance, and is thus a potential contributor to the development of PCOS. Therefore, AhR could be a potential new therapeutic target for PCOS. Video Abstract.