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1.
J Immunol ; 209(5): 991-1000, 2022 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-36130126

RESUMO

Akt-1 and Akt-2 are the major isoforms of the serine/threonine Akt family that play a key role in controlling immune responses. However, the involvement of Akt-1 and Akt-2 isoforms in antifungal innate immunity is completely unknown. In this study, we show that Akt2 -/-, but not Akt1 -/-, mice are protected from lethal Candida albicans infection. Loss of Akt-2 facilitates the recruitment of neutrophils and macrophages to the spleen and increases reactive oxygen species expression in these cells. Treating C57BL/6 mice with a specific inhibitor for Akt-2, but not Akt-1, provides protection from lethal C. albicans infection. Our data demonstrate that Akt-2 inhibits antifungal innate immunity by hampering neutrophil and macrophage recruitment to spleens and suppressing oxidative burst, myeloperoxidase activity, and NETosis. We thus describe a novel role for Akt-2 in the regulation of antifungal innate immunity and unveil Akt-2 as a potential target for the treatment of fungal sepsis.


Assuntos
Candida albicans , Candidíase , Proteínas Proto-Oncogênicas c-akt/metabolismo , Animais , Antifúngicos , Camundongos , Camundongos Endogâmicos C57BL , Neutrófilos , Peroxidase/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Serina/metabolismo , Treonina/metabolismo
2.
J Virol ; 96(8): e0027922, 2022 04 27.
Artigo em Inglês | MEDLINE | ID: mdl-35353002

RESUMO

Sp100 (speckled protein 100 kDa) is a constituent component of nuclear structure PML (promyelocytic leukemia) bodies, playing important roles in mediating intrinsic and innate immunity. The Sp100 gene encodes four isoforms with distinct roles in the transcriptional regulation of both cellular and viral genes. Since Sp100 is a primary intranuclear target of infected-cell protein 0 (ICP0), an immediate early E3 ligase encoded by herpes simplex virus 1 (HSV-1), previous investigations attempting to analyze the functions of individual Sp100 variants during HSV-1 infection mostly avoided using a wild-type virus. Therefore, the role of Sp100 under natural infection by HSV-1 remains to be clarified. Here, we reappraised the antiviral capacity of four Sp100 isoforms during infection by a nonmutated HSV-1, examined the molecular behavior of the Sp100 protein in detail, and revealed the following intriguing observations. First, Sp100 isoform A (Sp100A) inhibited wild-type HSV-1 propagation in HEp-2, Sp100-/-, and PML-/- cells. Second, endogenous Sp100 is located in both the nucleus and the cytoplasm. During HSV-1 infection, the nuclear Sp100 level decreased drastically upon the detection of ICP0 in the same subcellular compartment, but cytosolic Sp100 remained stable. Third, transfected Sp100A showed subcellular localizations similar to those of endogenous Sp100 and matched the protein size of endogenous cytosolic Sp100. Fourth, HSV-1 infection induced increased secretion of endogenous Sp100 and ectopically expressed Sp100A, which copurified with extracellular vesicles (EVs) but not infectious virions. Fifth, the Sp100A level in secreting cells positively correlated with its level in EVs, and EV-associated Sp100A restricted HSV-1 in recipient cells. IMPORTANCE Previous studies show that the PML body component Sp100 protein is immediately targeted by ICP0 of HSV-1 in the nucleus during productive infection. Therefore, extensive studies investigating the interplay of Sp100 isoforms with HSV-1 were conducted using a mutant virus lacking ICP0 or in the absence of infection. The role of Sp100 variants during natural HSV-1 infection remains blurry. Here, we report that Sp100A potently and independently inhibited wild-type HSV-1 and that during HSV-1 infection, cytosolic Sp100 remained stable and was increasingly secreted into the extracellular space, in association with EVs. Furthermore, the Sp100A level in secreting cells positively correlated with its level in EVs and the anti-HSV-1 potency of these EVs in recipient cells. In summary, this study implies an active antiviral role of Sp100A during wild-type HSV-1 infection and reveals a novel mechanism of Sp100A to restrict HSV-1 through extracellular communications.


Assuntos
Antígenos Nucleares , Autoantígenos , Herpes Simples , Herpesvirus Humano 1 , Interações entre Hospedeiro e Microrganismos , Corpos Nucleares da Leucemia Promielocítica , Antígenos Nucleares/metabolismo , Antivirais/metabolismo , Autoantígenos/metabolismo , Herpes Simples/genética , Herpesvirus Humano 1/metabolismo , Humanos , Corpos Nucleares da Leucemia Promielocítica/metabolismo , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo , Proteínas Virais/genética , Proteínas Virais/metabolismo
3.
Environ Res ; 236(Pt 1): 116738, 2023 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-37495066

RESUMO

As human society and industrialization have progressed, harmful algal blooms have contributed to global ecological pollution which makes the development of a novel and effective algal control strategy imminent. This is because existing physical and chemical methods for dealing with the problem have issues like cost and secondary pollution. Benefiting from their environmentally friendly and biocompatible properties, white-rot fungi (WRF) have been studied to control algal growth. WRF control algae by using algae for carbon or nitrogen, antagonism, and enhancing allelopathies. It can be better applied to practice by immobilization. This paper reviews the mechanism for WRF control of algae growth and its practical application. It demonstrates the limitations of WRF controlling algae growth and aids the further study of biological methods to regulate eutrophic water in algae growth research. In addition, it provides theoretical support for the fungi controlling algae growth.


Assuntos
Basidiomycota , Eutrofização , Humanos , Proliferação Nociva de Algas , Fungos
4.
Anim Biotechnol ; 32(4): 461-469, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32022644

RESUMO

Copy number variation (CNV) as an important source of genetic phenotypic and variation is related to complex phenotypic traits. The aim of this study was to investigate the potential associations of BAG4 (Bcl-2-associated athanogene 4) copy numbers variations with sheep growth traits in three Chinese sheep breeds (CKS, STHS, and HS). BAG4 is located within the stature and udder attachment quantitative trait loci (QTL) in sheep. Expression profiling revealed that the BAG4 gene was widely expressed in the tissues of sheep. The distribution of BAG4 gene copy number showed that the loss of copy number was more dominant in CKS and HS which was different from that in STHS. Statistical analysis revealed that the BAG4 CNV was significantly associated with body height in CKS (p < 0.05), with body slanting length in HS (p < 0.05), and with body height and hip cross height in STHS (p < 0.05). The χ2 values showed significant differences in the BAG4 CNV distribution frequency between varieties. In conclusion, the results establish the association between BAG4 CNV and sheep traits and suggest that BAG4 CNV may be a promising marker for the molecular breeding of Chinese sheep.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/genética , Variações do Número de Cópias de DNA , Locos de Características Quantitativas , Ovinos , Animais , China , Fenótipo , Ovinos/genética , Ovinos/crescimento & desenvolvimento
5.
Am J Public Health ; 110(12): 1837-1843, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33058712

RESUMO

Objectives. To compare the epidemic prevention ability of COVID-19 of each province in China and to evaluate the existing prevention and control capacity of each province.Methods. We established a quasi-Poisson linear mixed-effects model using the case data in cities outside Wuhan in Hubei Province, China. We adapted this model to estimate the number of potential cases in Wuhan and obtained epidemiological parameters. We estimated the initial number of cases in each province by using passenger flowrate data and constructed the extended susceptible-exposed-infectious-recovered model to predict the future disease transmission trends.Results. The estimated potential cases in Wuhan were about 3 times the reported cases. The basic reproductive number was 3.30 during the initial outbreak. Provinces with more estimated imported cases than reported cases were those in the surrounding provinces of Hubei, including Henan and Shaanxi. The regions where the number of reported cases was closer to the predicted value were most the developed areas, including Beijing and Shanghai.Conclusions. The number of confirmed cases in Wuhan was underestimated in the initial period of the outbreak. Provincial surveillance and emergency response capabilities vary across the country.


Assuntos
COVID-19/epidemiologia , COVID-19/prevenção & controle , China/epidemiologia , Humanos , Pandemias , SARS-CoV-2 , Índice de Gravidade de Doença , Meios de Transporte/estatística & dados numéricos , Viagem/estatística & dados numéricos
6.
Anim Biotechnol ; 31(1): 42-51, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30570383

RESUMO

Cellular retinoic acid binding protein 2 (CRABP2) is essential to myoblast differentiation. However, there was no report about the function of CRABP2 gene in cattle. This study explored the association of CRABP2 gene polymorphisms with growth traits in cattle breeds by several methods, such as DNA sequencing, PCR, PCR-RFLP and forced PCR-RFLP. Two sequence variants were determined. There were 621 individuals in six cattle breeds from China for the experiment, and three breeds were used to test validation of polymorphisms and extent of linkage disequilibrium (LD). The results showed that both SNPs (SNP1, g.2458 G > T, SNP2, g.3878 G > A) were in intron1. Two SNPs were in low linkage disequilibrium. Association analysis suggested that SNP1 had the significant difference on growth traits with body height, height at hip cross and body slanting length (P < .05), while SNP2 showed a significant difference in growth traits with body height, height at hip cross and body slanting length(P < .05). The results of this investigation displayed that the CRABP2 gene is an available candidate gene and may be used for breed selection and conservation.


Assuntos
Bovinos/fisiologia , Estudos de Associação Genética/veterinária , Polimorfismo de Nucleotídeo Único/genética , Animais , Cruzamento , Bovinos/genética , Bovinos/crescimento & desenvolvimento , Feminino , Genótipo , Desequilíbrio de Ligação , Camundongos , Fenótipo , Polimorfismo de Fragmento de Restrição , Característica Quantitativa Herdável , Análise de Sequência de DNA/veterinária
7.
J Cell Physiol ; 234(10): 18361-18370, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-30887511

RESUMO

Long noncoding RNA maternally expressed gene 3 (lncRNA-MEG3) is an important regulator in multiple biological functions. However, lncRNA-MEG3's function in cattle growth and regulatory mechanism on bovine skeletal muscle development has not yet been well studied. In this project, we first investigated lncRNA-MEG3's expression profile and detected that it was highly expressed in bovine skeletal muscle tissue and its RNA level was kept increasingly during the early phase of bovine primary myoblast differentiation. Using luciferase reporter assays, we identified the lncRNA-MEG3 core promoter containing putative transcription factor binding site for myocyte enhancer factor 2C (MEF2C). Interestingly, we found that LncRNA-MEG3 could significantly upregulate and downregulate myosin heavy chain ( MHC), myogenin ( MyoG), and MEF2C through overexpression and RNAi strategies, respectively. Using luciferase reporter assays, we also verified lncRNA-MEG3 as a miR-135 sponge. Overexpression of miR-135 markedly inhibited the wild type of lncRNA-MEG3, but not the mutant lncRNA-MEG3 reporter. The luciferase activity of miR-135 sensor could be rescued by lncRNA-MEG3 via competing for miRNA-135. In addition, the luciferase activity of MEF2C was significantly upregulated by the wild type of lncRNA-MEG3. This study, for the first time, revealed that lncRNA-MEG3 could promote bovine skeletal muscle differentiation via interacting with miRNA-135 and MEF2C. The results were valuable for further studies and applications of lncRNA related roles in beef molecular breeding.


Assuntos
Diferenciação Celular/genética , MicroRNAs/genética , Mioblastos/fisiologia , RNA Longo não Codificante/genética , Animais , Apoptose/genética , Bovinos , Diferenciação Celular/fisiologia , Proliferação de Células/genética , Regulação para Baixo/genética , Fatores de Transcrição MEF2/genética , Desenvolvimento Muscular/genética , Músculo Esquelético/fisiologia , Interferência de RNA/fisiologia , Ativação Transcricional/genética , Regulação para Cima/genética
8.
J Cell Physiol ; 234(4): 3720-3729, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30317561

RESUMO

Skeletal muscle is the most abundant tissue in the body. The development of skeletal muscle cell is complex and affected by many factors. A sea of microRNAs (miRNAs) have been identified as critical regulators of myogenesis. MiR-208b, a muscle-specific miRNA, was reported to have a connection with fiber type determination. However, whether miR-208b has effect on proliferation of muscle cell was under ascertained. In our study, cyclin-dependent kinase inhibitor 1A (CDKN1A), which participates in cell cycle regulation, was predicted and then validated as one target gene of miR-208b. We found that overexpression of miR-208b increased the expression of cyclin D1, cyclin E1, and cyclin-dependent kinase 2 at the levels of messenger RNA and protein in cattle primary myoblasts in vivo and in vitro. Flow cytometry showed that forced expression of miR-208b increased the percentage of cells at the S phase and decreased the percentage of cells at the G0/G1 phase. These results indicated that miR-208b participates in the cell cycle regulation of cattle primary myoblast cells. 5-Ethynyl-20-deoxyuridine and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assays showed that overexpression of miR-208b promoted the proliferation of cattle primary myoblasts. Therefore, we conclude that miR-208b participates in the cell cycle and proliferation regulation of cattle primary skeletal muscle cell through the posttranscriptional downregulation of CDKN1A.


Assuntos
Ciclo Celular , Proliferação de Células , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , MicroRNAs/metabolismo , Doenças Musculares/metabolismo , Mioblastos Esqueléticos/metabolismo , Regiões 3' não Traduzidas , Animais , Sítios de Ligação , Gatos , Diferenciação Celular , Inibidor de Quinase Dependente de Ciclina p21/genética , Modelos Animais de Doenças , Regulação da Expressão Gênica , Células HEK293 , Humanos , Camundongos Endogâmicos C57BL , MicroRNAs/genética , Doenças Musculares/genética , Doenças Musculares/patologia , Mioblastos Esqueléticos/patologia , Processamento Pós-Transcricional do RNA , Transdução de Sinais
9.
Funct Integr Genomics ; 18(5): 559-567, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29737453

RESUMO

Copy number variation (CNV) of DNA sequences, functionally significant but yet fully ascertained, is believed to confer considerable increments in unexplained heritability of quantitative traits. Identification of phenotype-associated CNVs (paCNVs) therefore is a pressing need in CNV studies to speed up their exploitation in cattle breeding programs. Here, we provided a new avenue to achieve this goal that is to project the published CNV data onto meta-quantitative trait loci (meta-QTL) map which connects causal genes with phenotypes. Any CNVs overlapping meta-QTL therefore will be potential paCNVs. This study reported potential paCNVs in Bos taurus autosome 3 (BTA3). Notably, overview indexes and CNVs both highlighted a narrower region (BTA3 54,500,000-55,000,000 bp, named BTA3_INQTL_6) within one constructed meta-QTL. Then, we ascertained guanylate-binding protein 4 (GBP4) among the nine positional candidate genes was significantly associated with adult cattle stature, including body weight (BW, P < 0.05) and withers height (WHT, P < 0.05), fitting GBP4 CNV either with three levels or with six levels in the model. Although higher copy number downregulated the mRNA levels of GBP2 (P < 0.05) and GBP4 (P < 0.05) in 1-Mb window (54.0-55.0 Mb) in muscle and adipose, additional analyses will be needed to clarify the causality behind the ascertained association.


Assuntos
Variações do Número de Cópias de DNA , Proteínas de Ligação ao GTP/genética , Genoma , Locos de Características Quantitativas , Animais , Peso Corporal , Cruzamento , Bovinos , Mapeamento Cromossômico , Proteínas de Ligação ao GTP/metabolismo , Genótipo , Fenótipo , Característica Quantitativa Herdável
10.
J Immunol ; 195(8): 3769-80, 2015 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-26363056

RESUMO

Although dendritic cells (DCs) have been widely demonstrated to play essential roles in initiation of Th2 responses in helminth infections and allergic reactions, the mechanisms remain uncertain largely because DCs do not produce IL-4. In present investigation, we have uncovered a novel subset of DCs from mice infected with Th2-provoking pathogens Schistosoma japonica, which independently promoted Th2 cells via IL-4-dependent pathway. These DCs contained similar levels of IL-4 mRNA and higher levels of IL-12p40 mRNA comparing to basophils, correlating to their Th2-promoting and Th1-promoting dual polarization capacities. Characterized by expression of FcεRI(+), these DCs were induced independent of T cells. Further investigations revealed that Th2-promoting FcεRI(+) DCs were monocyte-derived inflammatory DCs, which were sufficient to induce Th2 cells in vivo. Egg Ags together with GM-CSF or IL-3 alone were able to stimulate the generation of Th2-promoting FcεRI(+) DCs from bone marrow cells in vitro. To our knowledge, our data for the first time demonstrate that IL-4-producing DCs are induced under some Th2-provoking situations, and they should play important roles in initiation of Th2 response.


Assuntos
Células Dendríticas/imunologia , Interleucina-4/imunologia , Schistosoma japonicum/imunologia , Esquistossomose Japônica/imunologia , Transdução de Sinais/imunologia , Células Th2/imunologia , Animais , Células Dendríticas/patologia , Subunidade p40 da Interleucina-12/genética , Subunidade p40 da Interleucina-12/imunologia , Interleucina-4/genética , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Knockout , Receptores de IgE/genética , Receptores de IgE/imunologia , Esquistossomose Japônica/genética , Esquistossomose Japônica/patologia , Transdução de Sinais/genética , Células Th2/patologia
11.
Immunology ; 149(2): 238-51, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27315109

RESUMO

Aluminium hydroxide (alum), the most widely used adjuvant in human and animal vaccines, has long been known to promote T helper type 2 (Th2) responses and Th2-associated humoral responses, but the mechanisms have remained poorly understood. In this study, we explored whether alum is able to directly modulate antigen-presenting cells to enhance their potency for Th2 polarization. We found that alum treatment of dendritic cells failed to show any Th2-promoting activities. In contrast, alum was able to enhance the capacity of basophils to induce Th2 cells. When basophils from interleukin-4 (IL-4) knockout mice were examined, the intrinsic Th2-promoting activities by basophils were largely abrogated, but the alum-enhanced Th2-promoting activities on basophils were still detectable. More importantly, Th2-promoting adjuvant activities by alum found in IL-4 knockout mice were also largely reduced when basophils were depleted by antibody administration. Therefore, basophils can mediate Th2-promoting activities by alum both in vitro and in vivo through IL-4-independent mechanisms. Further studies revealed that secreted soluble molecules from alum-treated basophils were able to confer the Th2-promoting activities, and neutralization of thymic stromal lymphopoietin or IL-25 attenuated the IL-4-independent development of Th2 cells elicited by alum-treated basophils. Finally, alum was able to activate NACHT, LRR and PYD domains-containing protein 3 (NLRP3) inflammasome in murine basophils in the same way as alum in professional antigen-presenting cells, but NLRP3 was not required for Th2-promoting activities on basophils by alum in vitro. These results demonstrated that alum can enhance the capacities of basophils to polarize Th2 cells via IL-4- and NLRP3-independent pathways.


Assuntos
Adjuvantes Imunológicos/administração & dosagem , Compostos de Alúmen/administração & dosagem , Basófilos/imunologia , Células Dendríticas/imunologia , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Células Th2/imunologia , Vacinas/imunologia , Animais , Apresentação de Antígeno , Diferenciação Celular , Células Cultivadas , Humanos , Inflamassomos/metabolismo , Interleucina-4/genética , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Knockout
12.
Stat Methods Med Res ; : 9622802241259174, 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38865137

RESUMO

Estimation of the 100p percent lethal dose (LD100p) is of great interest to pharmacologists for assessing the toxicity of certain compounds. However, most existing literature focuses on the interval estimation of LD100p and little attention has been paid to its point estimation. Currently, the most commonly used method for estimating the LD100p is the maximum likelihood estimator (MLE), which can be represented as a ratio estimator, with the denominator being the slope estimated from the logistic regression model. However, the MLE can be seriously biased when the sample size is small, a common nature in such studies, or when the dose-response curve is relatively flat (i.e. the slope approaches zero). In this study, we address these issues by developing a novel penalised maximum likelihood estimator (PMLE) that can prevent the denominator of the ratio from being close to zero. Similar to the MLE, the PMLE is computationally simple and thus can be conveniently used in practice. Moreover, with a suitable penalty parameter, we show that the PMLE can (a) reduce the bias to the second order with respect to the sample size and (b) avoid extreme estimates. Through simulation studies and real data applications, we show that the PMLE generally outperforms the existing methods in terms of bias and root mean square error.

13.
Environ Int ; 183: 108432, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38219542

RESUMO

Micro- and nanoplastics (MNPs), emerging as pervasive environmental pollutants, present multifaceted threats to diverse ecosystems. This review critically examines the ability of MNPs to traverse biological barriers in fish, leading to their accumulation in gonadal tissues and subsequent reproductive toxicity. A focal concern is the potential transgenerational harm, where offspring not directly exposed to MNPs exhibit toxic effects. Characterized by extensive specific surface areas and marked surface hydrophobicity, MNPs readily adsorb and concentrate other environmental contaminants, potentially intensifying reproductive and transgenerational toxicity. This comprehensive analysis aims to provide profound insights into the repercussions of MNPs on fish reproductive health and progeny, highlighting the intricate interplay between MNPs and other pollutants. We delve into the mechanisms of MNPs-induced reproductive toxicity, including gonadal histopathologic alterations, oxidative stress, and disruptions in the hypothalamic-pituitary-gonadal axis. The review also underscores the urgency for future research to explore the size-specific toxic dynamics of MNPs and the long-term implications of chronic exposure. Understanding these aspects is crucial for assessing the ecological risks posed by MNPs and formulating strategies to safeguard aquatic life.


Assuntos
Poluentes Ambientais , Poluentes Químicos da Água , Animais , Ecossistema , Microplásticos , Peixes , Gônadas , Plásticos
14.
Adv Healthc Mater ; : e2400514, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38652681

RESUMO

Gliomas, the most prevalent primary brain tumors, pose considerable challenges due to their heterogeneity, intricate tumor microenvironment (TME), and blood-brain barrier (BBB), which restrict the effectiveness of traditional treatments like surgery and chemotherapy. This review provides an overview of engineered cell membrane technologies in glioma therapy, with a specific emphasis on targeted drug delivery and modulation of the immune microenvironment. This study investigates the progress in engineered cell membranes, encompassing physical, chemical, and genetic alterations, to improve drug delivery across the BBB and effectively target gliomas. The examination focuses on the interaction of engineered cell membrane-coated nanoparticles (ECM-NPs) with the TME in gliomas, emphasizing their potential to modulate glioma cell behavior and TME to enhance therapeutic efficacy. The review further explores the involvement of ECM-NPs in immunomodulation techniques, highlighting their impact on immune reactions. While facing obstacles related to membrane stability and manufacturing scalability, the review outlines forthcoming research directions focused on enhancing membrane performance. This review underscores the promise of ECM-NPs in surpassing conventional therapeutic constraints, proposing novel approaches for efficacious glioma treatment.

15.
Adv Sci (Weinh) ; 11(9): e2305907, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38126621

RESUMO

Cell cycle dysregulation is a defining feature of breast cancer. Here, 1-methyl-nicotinamide (1-MNA), metabolite of nicotinamide N-methyltransferase(NNMT) is identified, as a novel driver of cell-cycle progression in breast cancer. NNMT, highly expressed in breast cancer tissues, positively correlates with tumor grade, TNM stage, Ki-67 index, and tumor size. Ablation of NNMT expression dramatically suppresses cell proliferation and causes cell-cycle arrest in G0/G1 phase. This phenomenon predominantly stems from the targeted action of 1-MNA, resulting in a specific down-regulation of p27 protein expression. Mechanistically, 1-MNA expedites the degradation of p27 proteins by enhancing cullin-1 neddylation, crucial for the activation of Cullin-1-RING E3 ubiquitin ligase(CRL1)-an E3 ubiquitin ligase targeting p27 proteins.  NNMT/1-MNA specifically up-regulates the expression of UBC12, an E2 NEDD8-conjugating enzyme required for cullin-1 neddylation. 1-MNA showes high binding affinity to UBC12, extending the half-life of UBC12 proteins via preventing their localization to lysosome for degradation. Therefore, 1-MNA is a bioactive metabolite that promotes breast cancer progression by reinforcing neddylation pathway-mediated p27 degradation. The study unveils the link between NNMT enzymatic activity with cell-cycle progression, indicating that 1-MNA may be involved in the remodeling of tumor microenvironment.


Assuntos
Neoplasias da Mama , Proteínas Culina , Humanos , Feminino , Proteínas Culina/metabolismo , Proteína NEDD8/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Processamento de Proteína Pós-Traducional , Microambiente Tumoral , Nicotinamida N-Metiltransferase/metabolismo
16.
Heliyon ; 10(7): e28429, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38590888

RESUMO

Rapid ascent to high-altitude areas above 2500 m often leads to acute high altitude illness (AHAI), posing significant health risks. Current models for AHAI research are limited in their ability to accurately simulate the high-altitude environment for drug screening. Addressing this gap, a novel static self-assembled water vacuum transparent chamber was developed to induce AHAI in zebrafish. This study identified 6000 m for 2 h as the optimal condition for AHAI induction in zebrafish. Under these conditions, notable behavioral changes including slow movement, abnormal exploration behavior and static behavior in the Novel tank test. Furthermore, this model demonstrated changes in oxidative stress-related markers included increased levels of malondialdehyde, decreased levels of glutathione, decreased activities of superoxide dismutase and catalase, and increased levels of inflammatory markers IL-6, IL-1ß and TNF-α, and inflammatory cell infiltration and mild edema in the gill tissue, mirroring the clinical pathophysiology observed in AHAI patients. This innovative zebrafish model not only offers a more accurate representation of the high-altitude environment but also provides a high-throughput platform for AHAI drug discovery and pathogenesis research.

17.
Artigo em Chinês | MEDLINE | ID: mdl-24812882

RESUMO

UNLABELLED: OBJECTIVE; To observe the changes in various dendritic cell (DC) subsets, macrophages, basophils, eosinophils and mast cells in mouse spleen before and after Schistosoma japonicum infection induced Th2 response. METHODS: C57BL6 mice were infected with 20 S. japonicum cercariae via abdominal skin. Before infection and at 2, 4, and 6 weeks post-infection, the mice were sacrificed and spleen was removed. The frequencies of non-T, non-B basophils (NTNB), eosinophils, mast cells, subsets of DC and macrophages in the spleen were measured by flow cytometry. RESULTS: At 4 weeks after infection, when Th2 cells started to occur, the proportion of CD11c+CD8+DC and CD11c+CD4+DC in B220CD11c+DC increased from 7.4% and 7.9% before infection to 17.1% and 12.0%, respectively. During the infection, CD11c+CD4-CD8-DC, the majority of B220CD11c+DC, remained on a nearly constant level (70%); the percentage of B220+ CD11c+ DC in NTNB decreased. The macrophages were subdivided into two subsets: F4/80+CD11b(int) and F4/80+CD11b(high). The percentage of F4/80+CD11b(int) and F4/80+CD11b(high) in NTNB dropped from 15.4% and 13.7% before infection to 2.7% and 8.6% at 4 weeks post-infection. The proportion of CD11b high macrophages in F4/80+ cells significantly increased from 47.1% before infection to 75.5% at 4 weeks after infection. During S. japonicum infection, eosinophil percentage in the spleen gradually increased, while the frequency of basophils and mast cells in NTNB greatly decreased. CONCLUSION: At the time when Th2 response starts to occur, the frequency of CD11c+CD8+DC and CD11c+CD4+DC in CD11c+ dendritic cells increases. Once Th2 immune response established, the eosinophil frequency increases.


Assuntos
Células Apresentadoras de Antígenos/citologia , Esquistossomose Japônica/imunologia , Baço/citologia , Animais , Basófilos/imunologia , Células Dendríticas , Eosinófilos/imunologia , Feminino , Citometria de Fluxo , Macrófagos/imunologia , Mastócitos/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Schistosoma japonicum , Esquistossomose Japônica/parasitologia , Baço/imunologia
18.
Front Microbiol ; 14: 1205906, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37396389

RESUMO

HSV-1 hijacks the cellular vesicular secretion system and promotes the secretion of extracellular vesicles (EVs) from infected cells. This is believed to facilitate the maturation, secretion, intracellular transportation and immune evasion of the virus. Intriguingly, previous studies have shown that noninfectious EVs from HSV-1-infected cells exert antiviral effects on HSV-1 and have identified host restrictive factors, such as STING, CD63, and Sp100 packed in these lipid bilayer-enclosed vesicles. Octamer-binding transcription factor-1 (Oct-1) is shown here to be a pro-viral cargo in non-virion-containing EVs during HSV-1 infection and serves to facilitate virus dissemination. Specifically, during HSV-1 infection, the nuclear localized transcription factor Oct-1 displayed punctate cytosolic staining that frequently colocalized with VP16 and was increasingly secreted into the extracellular space. HSV-1 grown in cells bereft of Oct-1 (Oct-1 KO) was significantly less efficient at transcribing viral genes during the next round of infection. In fact, HSV-1 promoted increased exportation of Oct-1 in non-virion-containing EVs, but not the other VP16-induced complex (VIC) component HCF-1, and EV-associated Oct-1 was promptly imported into the nucleus of recipient cells to facilitate the next round of HSV-1 infection. Interestingly, we also found that EVs from HSV-1-infected cells primed cells for infection by another RNA virus, vesicular stomatitis virus. In summary, this investigation reports one of the first pro-viral host proteins packed into EVs during HSV-1 infection and underlines the heterogenetic nature and complexity of these noninfectious double-lipid particles.

19.
Elife ; 122023 09 13.
Artigo em Inglês | MEDLINE | ID: mdl-37702383

RESUMO

The relative positions of viral DNA genomes to the host intranuclear environment play critical roles in determining virus fate. Recent advances in the application of chromosome conformation capture-based sequencing analysis (3 C technologies) have revealed valuable aspects of the spatiotemporal interplay of viral genomes with host chromosomes. However, to elucidate the causal relationship between the subnuclear localization of viral genomes and the pathogenic outcome of an infection, manipulative tools are needed. Rapid repositioning of viral DNAs to specific subnuclear compartments amid infection is a powerful approach to synchronize and interrogate this dynamically changing process in space and time. Herein, we report an inducible CRISPR-based two-component platform that relocates extrachromosomal DNA pieces (5 kb to 170 kb) to the nuclear periphery in minutes (CRISPR-nuPin). Based on this strategy, investigations of herpes simplex virus 1 (HSV-1), a prototypical member of the human herpesvirus family, revealed unprecedently reported insights into the early intranuclear life of the pathogen: (I) Viral genomes tethered to the nuclear periphery upon entry, compared with those freely infecting the nucleus, were wrapped around histones with increased suppressive modifications and subjected to stronger transcriptional silencing and prominent growth inhibition. (II) Relocating HSV-1 genomes at 1 hr post infection significantly promoted the transcription of viral genes, termed an 'Escaping' effect. (III) Early accumulation of ICP0 was a sufficient but not necessary condition for 'Escaping'. (IV) Subnuclear localization was only critical during early infection. Importantly, the CRISPR-nuPin tactic, in principle, is applicable to many other DNA viruses.


Assuntos
Herpesvirus Humano 1 , Humanos , Herpesvirus Humano 1/genética , Reposicionamento de Medicamentos , DNA Viral/genética , Núcleo Celular/genética , Citoplasma
20.
Comput Struct Biotechnol J ; 21: 3885-3893, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37602227

RESUMO

Colistin is considered as one of the last-resort antimicrobial agents for treating multidrug-resistant bacterial infections. Multidrug-resistant E. asburiae has been increasingly isolated from clinical patients, which posed a great challenge for antibacterial treatment. This study aimed to report a mcr-10 and blaNDM-1 co-carrying E. asburiae clinical isolate 5549 conferred a high-level resistance against colistin. Antibiotic susceptibility testing was performed using the microdilution broth method. Transferability of mcr-10 and blaNDM-1-carrying plasmids were investigated by conjugation experiments. Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) was used to identify modifications in lipid A. Whole genome sequencing and phylogenetic analysis between strain 5549 and a total of 301 E. asburiae genomes retrieved from NCBI database were performed. The genetic characteristics of mcr-10 and blaNDM-1-bearing plasmids were also analyzed. Our study indicated that strain 5549 showed extensively antibiotic-resistant trait, including colistin and carbapenem resistance. The mcr-10 and blaNDM-1 were carried by IncFIB/IncFII type p5549_mcr-10 (159417 bp) and IncN type p5549_NDM-1 (63489 bp), respectively. Conjugation assays identified that only the blaNDM-1-carrying plasmid could be successfully transferred to E. coli J53. Interestingly, mcr-10 did not mediate colistin resistance when it was cloned into E. coli DH5α. Mass spectrometry analysis showed the lipid A palmitoylation of the C-lacyl-oxo-acyl chain to the chemical structure of lipid A at m/z 2063 in strain 5549. In summary, this study is the first to report a mcr-10 and blaNDM-1 co-occurrence E. asburiae recovered from China. Our investigation revealed the distribution of different clonal lineage of E. asburiae with epidemiology perspective and the underlying mechanisms of colistin resistance. Active surveillance is necessary to control the further dissemination of multidrug-resistant E. asburiae.

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