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1.
Arch Biochem Biophys ; 705: 108919, 2021 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-33992597

RESUMO

Baicalin is a traditional Chinese herb purified from the root of Scutellaria baicalensis Georgi. In this study, we further analyzed the molecular mechanism behind the anti-tumor activity of Baicalin in colorectal cancer (CRC). The establishment of circular RNA (circRNA)/microRNA (miRNA)/messenger RNA (mRNA) axis was predicted by bioinformatic databases and verified by dual-luciferase reporter assay and RNA immunoprecipitation (RIP) assay. Baicalin dose-dependently reduced the expression of circRNA myosin heavy chain 9 (circMYH9) in CRC cells. Baicalin exposure suppressed the malignant phenotypes of CRC cells, which were largely reversed by the overexpression of circMYH9. CircMYH9 functioned as a molecular sponge for miR-761. CircMYH9 overexpression protected CRC cells from Baicalin-induced injury partly through down-regulating miR-761. MiR-761 interacted with the 3' untranslated region (3' UTR) of hepatoma-derived growth factor (HDGF) mRNA. CircMYH9 up-regulated HDGF expression partly through sponging miR-761 in CRC cells. MiR-761 silencing counteracted the anti-tumor activity of Baicalin partly through up-regulating HDGF in CRC cells. Baicalin suppresses xenograft tumor growth in vivo, and this suppressive effect was partly reversed by the overexpression of circMYH9. In conclusion, Baicalin exhibited an anti-tumor activity in CRC cells partly through down-regulating circMYH9 and HDGF and up-regulating miR-761.


Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Neoplasias Colorretais/patologia , Flavonoides/farmacologia , Fenótipo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Regulação para Baixo/efeitos dos fármacos , Humanos , MicroRNAs/genética
2.
Acta Virol ; 65(2): 149-159, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34130466

RESUMO

Circulation of dominant genotype VII of Newcastle disease virus (NDV) causes significant economic losses to the poultry industry in China. Although most of genotype VII NDV has frequently been isolated in China to date, the genome sequence difference between duck-origin and chicken-origin NDVs remains largely unknown. In this study, a NDV strain of Chicken/China/HB/2017 (HB), isolated during an outbreak in China, was subjected to genetic, biological, phylogenetic and the pathogenicity characterization. The complete genome of HB strain is 15,192 nucleotides (nt) long and consisting of six genes in the order of 3'-NP-P-M-F-HN-L-5'. Several amino acid mutations were identified in the functional domains of F and HN proteins, including fusion peptide, heptad repeat region, transmembrane domains, and neutralizing epitopes. Phylogenetic analysis based on the F gene revealed that the HB strain and three other duck-origin NDV strains in China were grouped under subgenotype VII.1.1 and shared 99.1~99.2% nucleotide identity. Additionally, the challenge experiment results showed that the strain was highly pathogenic with 100% morbidity and mortality. Virus shedding was detected from 2 days post-infection until the fifth day. In conclusion, this study offers our understanding of circulating strains of NDV and genes involved in virulence and evolution between different hosts. Keywords: Newcastle disease virus; China; complete genome; genotype VII; mutations.


Assuntos
Doença de Newcastle , Doenças das Aves Domésticas , Animais , Galinhas , China , Genoma Viral , Genótipo , Vírus da Doença de Newcastle/genética , Filogenia
3.
Environ Sci Technol ; 52(5): 2677-2685, 2018 03 06.
Artigo em Inglês | MEDLINE | ID: mdl-29420017

RESUMO

Nanoplastics (NPs) are becoming an emerging pollutant of global concern. A potential risk is that NPs may serve as carriers to increase the spreading of coexisting contaminants. In this study, we examined the effects of polystyrene nanoplastics (PSNPs, 100 nm), used as a model NP, on the transport of five organic contaminants of different polarity in saturated soil. The presence of low concentrations of PSNPs significantly enhanced the transport of nonpolar (pyrene) and weakly polar (2,2',4,4'-tetrabromodiphenyl ether) compounds, but had essentially no effects on the transport of three polar compounds (bisphenol A, bisphenol F, and 4-nonylphenol). The strikingly different effects of NPs on the transport of nonpolar/weakly polar versus polar contaminants could not be explained with different adsorption affinities, but was consistent with the polarity-dependent extents of desorption hysteresis. Notably, desorption hysteresis was only observed for nonpolar/weakly polar contaminants, likely because nonpolar compounds tended to adsorb in the inner matrices of glassy polymeric structure of polystyrene (resulting in physical entrapment of adsorbates), whereas polar compounds favored surface adsorption. This hypothesis was verified with supplemental adsorption and desorption experiments of pyrene and 4-nonylphenol using a dense, glassy polystyrene polymer and a flexible, rubbery polyethylene polymer. Overall, the findings of this study underscore the potentially significant environmental implication of NPs as contaminant carriers.


Assuntos
Poliestirenos , Poluentes do Solo , Adsorção , Polímeros , Solo
4.
Proc Natl Acad Sci U S A ; 112(45): 13794-9, 2015 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-26504210

RESUMO

Devastating floods due to Atlantic hurricanes are relatively rare events. However, the frequency of the most intense storms is likely to increase with rises in sea surface temperatures. Geoengineering by stratospheric sulfate aerosol injection cools the tropics relative to the polar regions, including the hurricane Main Development Region in the Atlantic, suggesting that geoengineering may mitigate hurricanes. We examine this hypothesis using eight earth system model simulations of climate under the Geoengineering Model Intercomparison Project (GeoMIP) G3 and G4 schemes that use stratospheric aerosols to reduce the radiative forcing under the Representative Concentration Pathway (RCP) 4.5 scenario. Global mean temperature increases are greatly ameliorated by geoengineering, and tropical temperature increases are at most half of those temperature increases in the RCP4.5. However, sulfate injection would have to double (to nearly 10 teragrams of SO2 per year) between 2020 and 2070 to balance the RCP4.5, approximately the equivalent of a 1991 Pinatubo eruption every 2 y, with consequent implications for stratospheric ozone. We project changes in storm frequencies using a temperature-dependent generalized extreme value statistical model calibrated by historical storm surges and observed temperatures since 1923. The number of storm surge events as big as the one caused by the 2005 Katrina hurricane are reduced by about 50% compared with no geoengineering, but this reduction is only marginally statistically significant. Nevertheless, when sea level rise differences in 2070 between the RCP4.5 and geoengineering are factored into coastal flood risk, we find that expected flood levels are reduced by about 40 cm for 5-y events and about halved for 50-y surges.

5.
Vet Sci ; 11(9)2024 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-39330826

RESUMO

The sugC gene of Streptococcus suis (S. suis) is a coding gene for the ATP-binding transporter-associated protein with strong pathogenicity. In order to reveal the effect of the sugC gene on the virulence of S. suis serotype 2, a wild-type strain of TJS75, isolated from fattening pigs' brain tissue samples, was used as a parent strain, and a knockout sugC gene (ΔsugC) and complementary strain (CΔsugC) were successfully constructed via homologous recombination technology. The biological characteristics of TJS75, ΔsugC and CΔsugC were compared and analyzed through growth curves, biochemical characteristics, hemolysis characteristics, cell infection tests and pathogenicity tests on BALB/c mice. The results of the growth characteristic experiments in vitro showed that the plateau stage growth period of ΔsugC was delayed compared to the TJS75 strain, but there was no difference in the total number of bacteria. The biochemical characteristics and hemolysis ability of ΔsugC in sheep blood had no difference compared with TJS75, but its adhesion and invasion abilities in PK-15 cells were decreased. Knockout of the sugC gene had no impact on the expression levels of adhesion-related genes in TJS75 in real-time PCR analysis. In addition, the LD50 of ΔsugC in BALB/c mice was 1.47 × 108 CFU, seven times higher than that of TJS75 (LD50 = 2.15 × 107 CFU). These results illustrate that the deletion of sugC reduced the virulence of TJS75 to BALB/c mice, but its role in the adhesion and invasion of PK-15 cells in this strain needs to be further explored. In summary, this study provides evidence that the sugC gene is a virulence-related gene in the S. suis serotype 2 strain and plays a crucial role in the adhesion and invasion of S. suis. This study lays a foundation for the further exploration of the potential virulence factors and pathogenesis of S. suis.

6.
Dev Cell ; 59(13): 1655-1667.e6, 2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38670102

RESUMO

Proteotoxic stress drives numerous degenerative diseases. Cells initially adapt to misfolded proteins by activating the unfolded protein response (UPR), including endoplasmic-reticulum-associated protein degradation (ERAD). However, persistent stress triggers apoptosis. Enhancing ERAD is a promising therapeutic approach for protein misfolding diseases. The ER-localized Zn2+ transporter ZIP7 is conserved from plants to humans and required for intestinal self-renewal, Notch signaling, cell motility, and survival. However, a unifying mechanism underlying these diverse phenotypes was unknown. In studying Drosophila border cell migration, we discovered that ZIP7-mediated Zn2+ transport enhances the obligatory deubiquitination of proteins by the Rpn11 Zn2+ metalloproteinase in the proteasome lid. In human cells, ZIP7 and Zn2+ are limiting for deubiquitination. In a Drosophila model of neurodegeneration caused by misfolded rhodopsin (Rh1), ZIP7 overexpression degrades misfolded Rh1 and rescues photoreceptor viability and fly vision. Thus, ZIP7-mediated Zn2+ transport is a previously unknown, rate-limiting step for ERAD in vivo with therapeutic potential in protein misfolding diseases.


Assuntos
Proteínas de Transporte de Cátions , Proteínas de Drosophila , Degradação Associada com o Retículo Endoplasmático , Retículo Endoplasmático , Zinco , Animais , Proteínas de Transporte de Cátions/metabolismo , Proteínas de Transporte de Cátions/genética , Zinco/metabolismo , Proteínas de Drosophila/metabolismo , Proteínas de Drosophila/genética , Humanos , Retículo Endoplasmático/metabolismo , Complexo de Endopeptidases do Proteassoma/metabolismo , Proteólise , Drosophila melanogaster/metabolismo , Resposta a Proteínas não Dobradas , Ubiquitinação , Movimento Celular , Drosophila/metabolismo
7.
Int J Biol Macromol ; 277(Pt 2): 132755, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38821295

RESUMO

Interferon-induced transmembrane 3 (IFITM3) is a membrane-associated protein that exhibits antiviral activities against a wide range of viruses through interactions with other cellular and viral proteins. However, knowledge of the mechanisms of IFITM3 in Porcine deltacoronavirus (PDCoV) infection has been lacking. In this study, we demonstrate that IFN-α treatment induces the upregulation of IFITM3 activity and thus attenuates PDCoV infection. PDCoV replication is inhibited in a dose-dependent manner by IFITM3 overexpression. To clarify the novel roles of IFITM3 during PDCoV infection, proteins that interact with IFITM3 were screened by TAP/MS in an ST cell line stably expressing IFITM3 via a lentivirus. We identified known and novel candidate IFITM3-binding proteins and analyzed the protein complexes using GO annotation, KEGG pathway analysis, and protein interaction network analysis. A total of 362 cellular proteins associate with IFITM3 during the first 24 h post-infection. Of these proteins, the relationship between IFITM3 and Rab9a was evaluated by immunofluorescence colocalization analysis using confocal microscopy. IFITM3 partially colocalized with Rab9a and Rab9a exhibited enhanced colocalization following PDCoV infection. We also demonstrated that IFITM3 interacts specifically with Rab9a. Our results considerably expand the protein networks of IFITM3, suggesting that IFITM3 participates in multiple cellular processes during PDCoV infection.


Assuntos
Proteínas de Membrana , Ligação Proteica , Proteínas de Membrana/metabolismo , Animais , Suínos , Coronavirus/metabolismo , Mapas de Interação de Proteínas , Cromatografia de Afinidade/métodos , Humanos , Replicação Viral , Proteínas de Ligação a RNA/metabolismo , Linhagem Celular , Espectrometria de Massas em Tandem , Interferon-alfa/metabolismo , Interferon-alfa/farmacologia
8.
bioRxiv ; 2023 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-37292980

RESUMO

Proteotoxic stress drives numerous degenerative diseases. In response to misfolded proteins, cells adapt by activating the unfolded protein response (UPR), including endoplasmic reticulum-associated protein degradation (ERAD). However persistent stress triggers apoptosis. Enhancing ERAD is a promising therapeutic approach for protein misfolding diseases. From plants to humans, loss of the Zn2+ transporter ZIP7 causes ER stress, however the mechanism is unknown. Here we show that ZIP7 enhances ERAD and that cytosolic Zn2+ is limiting for deubiquitination of client proteins by the Rpn11 Zn2+ metalloproteinase as they enter the proteasome in Drosophila and human cells. ZIP7 overexpression rescues defective vision caused by misfolded rhodopsin in Drosophila. Thus ZIP7 overexpression may prevent diseases caused by proteotoxic stress, and existing ZIP inhibitors may be effective against proteasome-dependent cancers.

9.
Adv Sci (Weinh) ; 10(20): e2205949, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37166058

RESUMO

Isocitrate dehydrogenase (IDH) mutation, a known pathologic classifier, initiates metabolic reprogramming in glioma cells and has been linked to the reaction status of glioma-associated microglia/macrophages (GAMs). However, it remains unclear how IDH genotypes contribute to GAM phenotypes. Here, it is demonstrated that gliomas expressing mutant IDH determine M1-like polarization of GAMs, while archetypal IDH induces M2-like polarization. Intriguingly, IDH-mutant gliomas secrete excess cholesterol, resulting in cholesterol-rich, pro-inflammatory GAMs without altering their cholesterol biosynthesis, and simultaneously exhibiting low levels of tumoral cholesterol due to expression remodeling of cholesterol transport molecules, particularly upregulation of ABCA1 and downregulation of LDLR. Mechanistically, a miR-19a/LDLR axis-mediated novel post-transcriptional regulation of cholesterol uptake is identified, modulated by IDH mutation, and influencing tumor cell proliferation and invasion. IDH mutation-induced PERK activation enhances cholesterol export from glioma cells via the miR-19a/LDLR axis and ABCA1/APOE upregulation. Further, a synthetic PERK activator, CCT020312 is introduced, which markedly stimulates cholesterol efflux from IDH wild-type glioma cells, induces M1-like polarization of GAMs, and consequently suppresses glioma cell invasion. The findings reveal an essential role of the PERK/miR-19a/LDLR signaling pathway in orchestrating gliomal cholesterol transport and the subsequent phenotypes of GAMs, thereby highlighting a novel potential target pathway for glioma therapy.


Assuntos
Neoplasias Encefálicas , Glioma , MicroRNAs , Humanos , Neoplasias Encefálicas/metabolismo , Colesterol , Glioma/metabolismo , Isocitrato Desidrogenase/genética , Microglia/metabolismo , MicroRNAs/genética
10.
Sci Total Environ ; 829: 154300, 2022 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-35271924

RESUMO

Formation of non-extractable residues (NERs) is the major fate of most environmental organic contaminants in soil, however, there is no direct evidence yet to support the assumed physical entrapment of NERs (i.e., type I NERs) inside soil humic substances. Here, we used 14C-radiotracer and silylation techniques to analyze NERs of six emerging and traditional organic contaminants formed in a suspension of humic acids (HA) under catalysis of the oxidative enzyme laccase. Laccase induced formation of both type I and covalently bound NERs (i.e., type II NERs) of bisphenol A, bisphenol F, and tetrabromobisphenol A to a large extent, and of bisphenol S (BPS) and sulfamethoxazole (SMX) to a less extent, while no induction for phenanthrene. The type I NERs were formed supposedly owing to laccase-induced alteration of primary (active groups) and secondary (conformation) structure of humic supramolecules, contributing surprisingly to large extents (23.5%-65.7%) to the total NERs, particularly for BPS and SMX, which both were otherwise not transformed by laccase catalysis. Electron-withdrawing sulfonyl group and bromine substitution significantly decreased amount and kinetics of NER formation, respectively. This study provides the first direct evidence for the formation of type I NERs in humic substances and implies a "Trojan horse" effect of such NERs in the environment.


Assuntos
Substâncias Húmicas , Poluentes do Solo , Catálise , Substâncias Húmicas/análise , Lacase/química , Solo/química , Poluentes do Solo/análise
11.
Front Immunol ; 13: 1107173, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36618383

RESUMO

Innate immunity is the first line of the cellular host to defend against viral infection. Upon infection, viruses can be sensed by the cellular host's pattern recognition receptors (PRRs), leading to the activation of the signaling cascade and the robust production of interferons (IFNs) to restrict the infection and replication of the viruses. However, numerous cunning viruses have evolved strategies to evade host innate immunity. The senecavirus A (SVA) is a newly identified member of the Picornaviridae family, causing severe vesicular or ulcerative lesions on the oral mucosa, snout, coronary bands, and hooves of pigs of different ages. During SVA infection, the cellular host will launch the innate immune response and various physiological processes to restrict SVA. In contrast, SVA has evolved several strategies to evade the porcine innate immune responses. This review focus on the underlying mechanisms employed by SVA to evade pattern recognition receptor signaling pathways, type I interferon (IFN-α/ß) receptor (IFNAR) signaling pathway, interferon-stimulated genes (ISGs) and autophagy, and stress granules. Deciphering the antiviral immune evasion mechanisms by SVA will enhance our understanding of SVA's pathogenesis and provide insights into developing antiviral strategies and improving vaccines.


Assuntos
Picornaviridae , Vírus , Suínos , Animais , Evasão da Resposta Imune , Antivirais , Interações Hospedeiro-Patógeno , Imunidade Inata , Interferon-alfa
12.
Front Microbiol ; 13: 925953, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35722302

RESUMO

Circular RNAs (circRNAs) are a new class of noncoding RNAs that play vital roles in many biological processes. Virus infection induces modifications in cellular circRNA transcriptomes and expresses viral circRNAs. The outbreaks of Hydropericardium-hepatitis syndrome (HHS) caused by fowl adenovirus serotype 4 (FAdV-4) have resulted in huge economic losses to the poultry industry worldwide. To investigate the expression of circRNAs during FAdV-4 infection, we performed transcriptome analysis of FAdV-4-infected leghorn male hepatoma (LMH) cells. In total, 19,154 cellular circRNAs and 135 differentially expressed (DE) cellular circRNAs were identified. The characteristics of the DE cellular circRNAs were analyzed and most of them were related to multiple biological processes according to GO and KEGG enrichment analysis. The accuracy of 10 cellular circRNAs were verified by semiquantitative RT-PCR and sequencing. The change trend was consistent with the RNA sequencing results. Moreover, 2014 viral circRNAs were identified and 10 circRNAs were verified by the same methods. Our analysis showed that seven circRNAs with the same 3' terminal and variable 5' terminal regions were located at pTP protein and DNA pol protein of FAdV-4, which may be generated via alternative splicing events. Moreover, the expression level of viral circRNAs was closely related to the replication efficiency of the virus and partial of the viral circRNAs promoted the replication of FAdV-4. Competing endogenous RNA analysis further showed that the effects of cellular and viral circRNAs on host or viral genes may act via miRNAs. Collectively, our findings first indicate that FAdV-4 infection induced the differential expression of cellular circRNAs and FAdV-4 also expressed viral circRNAs, some of which affected FAdV-4 replication. These findings will provide new clues for further understanding FAdV-4 and provide a basis for investigating host-virus interactions.

13.
Front Immunol ; 13: 951984, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35911774

RESUMO

Senecavirus A (SVA), also known as Seneca Valley virus, is a recently discovered picornavirus that can cause swine vesicular disease, posing a great threat to the global swine industry. It can replicate efficiently in cells, but the molecular mechanism remains poorly understood. This study determined the host's differentially expressed proteins (DEPs) during SVA infection using dimethyl labeling based on quantitative proteomics. Among the DE proteins, DDX21, a member of the DEAD (Asp-Glu-Ala-Asp)-box RNA helicase (DDX) family, was downregulated and demonstrated inhibiting SVA replication by overexpression and knockdown experiment. To antagonize this antiviral effect of DDX21, SVA infection induces the degradation of DDX21 by 2B and 3C proteins. The Co-IP results showed that 2B and 3C did not interact with DDX21, suggesting that the degradation of DDX21 did not depend on their interaction. Moreover, the 3C protein protease activity was necessary for the degradation of DDX21. Furthermore, our study revealed that the degradation of DDX21 by 2B and 3C proteins of SVA was achieved through the caspase pathway. These findings suggest that DDX21 was an effective antiviral factor for suppressing SVA infection and that SVA antagonized its antiviral effect by degrading DDX21, which will be useful to guide further studies into the mechanism of mutual regulation between SVA and the host.


Assuntos
Antivirais , Picornaviridae , Animais , Antivirais/farmacologia , Caspases , Picornaviridae/genética , Suínos , Proteínas Virais/metabolismo
14.
Diagn Pathol ; 16(1): 47, 2021 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-34030715

RESUMO

BACKGROUND: Colorectal cancer (CRC) is one of the third normal malignancy worldwide. Taurine-upregulated gene 1 (TUG1), a member of long noncoding RNAs (lncRNAs), has been reported to be involved in various cancers. However, the mechanism underlying TUG1 in the progression of CRC remains unclear. METHODS: The expression of TUG1, microRNA-542-3p (miR-542-3p), and tribbles homolog 2 (TRIB2) in CRC tissues and cells (LoVo and HCT116) were detected by quantitative real-time PCR (qRT-PCR). Methyl thiazolyl tetrazolium (MTT), transwell and flow cytometry assays were employed to evaluate the effects of TUG1 in CRC cells. The interaction between miR-542-3p and TUG1 or TRIB2 were verified by dual-luciferase reporter assay. A xenograft tumor model in nude mice was established to investigate the biological role of TUG1 in CRC in vivo. RESULTS: TUG1 was increased in CRC tissues and cells (LoVo and HCT116) in contrast with adjacent normal tissues and normal intestinal mucous cells (CCC-HIE-2). Downregulation of TUG1 or TRIB2 suppressed the proliferation, migration, invasion, and induced apoptosis in CRC cells. And knockdown of TUG1 repressed tumor growth in vivo. Besides, overexpression of TRIB2 reversed the effects of TUG1 depletion on the progression of CRC. Meanwhile, TUG1 interacted with miR-542-3p and TRIB2 was a target of miR-542-3p. Furthermore, miR-542-3p knockdown or TRIB2 overexpression partly reversed the suppression effect of TUG1 depletion on the Wnt/ß-catenin pathway. CONCLUSIONS: TUG1 served as a tumor promoter, impeded the progression of CRC by miR-542-3p/TRIB2 axis to inactivate of Wnt/ß-catenin pathway, which providing a novel target for CRC treatment.


Assuntos
Proteínas Quinases Dependentes de Cálcio-Calmodulina/metabolismo , Neoplasias Colorretais/metabolismo , MicroRNAs/metabolismo , RNA Longo não Codificante/metabolismo , Via de Sinalização Wnt , Animais , Apoptose , Proteínas Quinases Dependentes de Cálcio-Calmodulina/genética , Movimento Celular , Proliferação de Células , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Progressão da Doença , Feminino , Regulação Neoplásica da Expressão Gênica , Células HCT116 , Humanos , Masculino , Camundongos Nus , MicroRNAs/genética , Pessoa de Meia-Idade , Invasividade Neoplásica , RNA Longo não Codificante/genética , Carga Tumoral
15.
Front Microbiol ; 12: 745502, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34659180

RESUMO

Senecavirus A (SVA), also known as Seneca Valley virus, is a recently emerged picornavirus that can cause swine vesicular disease, posing a great threat to the global swine industry. A recombinant reporter virus (rSVA-Nluc) stably expressing the nanoluciferase (Nluc) gene between SVA 2A and 2B was developed to rapidly detect anti-SVA neutralizing antibodies and establish a high-throughput screen for antiviral agents. This recombinant virus displayed similar growth kinetics as the parental virus and remained stable for more than 10 passages in BHK-21 cells. As a proof-of-concept for its utility for rapid antiviral screening, this reporter virus was used to rapidly quantify anti-SVA neutralizing antibodies in 13 swine sera samples and screen for antiviral agents, including interferons ribavirin and interferon-stimulated genes (ISGs). Subsequently, interfering RNAs targeting different regions of the SVA genome were screened using the reporter virus. This reporter virus (rSVA-Nluc) represents a useful tool for rapid and quantitative screening and evaluation of antivirals against SVA.

16.
Curr Cancer Drug Targets ; 21(7): 558-574, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33949933

RESUMO

Gliomas are the most common type of malignant brain tumors. Despite significant medical advances, gliomas remain incurable and are associated with high mortality. Although numerous biomarkers of diagnostic value have been identified and significant progress in the prognosis of the outcome has been made, the treatment has not been parallelly improved during the last three decades. This review summarizes and discusses three aspects of recent discoveries related to glioma, with the objective to highlight the advantages of glioma-specific drugs targeting the cell of origin, microenvironment, and metabolism. Given the heterogeneous nature of gliomas, various cell populations have been implicated as likely sources of the tumor. Depending on the mutation(s) acquired by the cells, it is believed that neural stem/progenitor cells, oligodendrocyte progenitor cells, mature neurons, and glial cells can initiate cell transformation into a malignant phenotype. The level of tumorigenicity appears to be inversely correlated with the maturation of a given cell population. The microenvironment of gliomas includes non-cancer cells such as immune cells, fibroblasts, and cells of blood vessels, as well as secreted molecules and the extracellular matrix, and all these components play a vital role during tumor initiation and progression. We will discuss in detail how the tumor microenvironment can stimulate and drive the transformation of non-tumor cell populations into tumor-supporting cells or glioma cells. Metabolic reprogramming is a key feature of gliomas and is thought to reflect the adaptation to the increased nutritional requirements of tumor cell proliferation, growth, and survival. Mutations in the IDH gene can shape metabolic reprogramming and may generate some vulnerabilities in glioma cells, such as abnormal lipid metabolism and sensitivity to endoplasmic reticulum stress (ERS). We will analyze the prominent metabolic features of malignant gliomas and the key pathways regulating glioma metabolism. This review is intended to provide a conceptual background for the development of glioma therapies based on the properties of tumor cell populations, microenvironment, and metabolism.


Assuntos
Neoplasias Encefálicas , Glioma , Neoplasias Encefálicas/tratamento farmacológico , Transformação Celular Neoplásica , Glioma/tratamento farmacológico , Humanos , Prognóstico , Microambiente Tumoral
17.
Food Nutr Res ; 652021.
Artigo em Inglês | MEDLINE | ID: mdl-33776618

RESUMO

BACKGROUND: Obesity is a principal risk factor for the development of type 2 diabetes and cardiovascular diseases. Natural plants and/or foods play an important role in the management of obesity. Acalypha australis L. (AAL) is a kind of potherb popular among Asian populations, and it is also consumed as a food ingredient and traditional herbal medicine. OBJECTIVE: We investigated the effects of water extract from AAL on high-fat-diet (HFD)-induced obese mice and 3T3-L1 adipocytes to develop a new functional food material. DESIGN: Nine-week-old male mice were randomly divided into control (chow diet, n = 6) and HFD (n = 30) group. From 12-weeks onward, mice in the HFD group were further separated into model (saline, 6 mL/kg), simvastatin (0.11 mg/mL, 6 mL/kg), and AAL treatment (low, middle, and high dosage: 300, 600, and 900 mg/kg) group, with 6 animals per group, while mice in the control group were treated with saline (6 mL/kg). Food intake, body/fat weight, liver/kidney indexes, and lipid profiles were determined. Tissues were fixed with formalin for pathological examination. Western blotting and PCR were performed to evaluate the protein and mRNA expression in 3T3-L1 adipocytes. Oil Red O staining was used to determine lipid accumulation. RESULTS: AAL administration significantly suppressed body weight gain, and reduced fat pad weight and Lee's index in obese mice, but had no effect on liver/kidney index. AAL also reduced serum cholesterol, triglyceride, and LDL-C and increased HDL-C levels. Histological analysis revealed that AAL significantly ameliorated lipid accumulation in the liver and subcutaneous adipose tissue. In vitro, Oil Red O staining showed that AAL inhibited adipose differentiation by down-regulating the gene and protein expression of PPARγ and C/EBPα. AAL also reversed HFD-induced intestinal dysbacteriosis. CONCLUSION: AAL water-soluble extract has a significant anti-adipogenic effect in the HFD-induced obese mice model.

18.
Nat Commun ; 11(1): 5726, 2020 11 12.
Artigo em Inglês | MEDLINE | ID: mdl-33184261

RESUMO

Apoptosis is an ancient and evolutionarily conserved cell suicide program. During apoptosis, executioner caspase enzyme activation has been considered a point of no return. However, emerging evidence suggests that some cells can survive caspase activation following exposure to apoptosis-inducing stresses, raising questions as to the physiological significance and underlying molecular mechanisms of this unexpected phenomenon. Here, we show that, following severe tissue injury, Drosophila wing disc cells that survive executioner caspase activation contribute to tissue regeneration. Through RNAi screening, we identify akt1 and a previously uncharacterized Drosophila gene CG8108, which is homologous to the human gene CIZ1, as essential for survival from the executioner caspase activation. We also show that cells expressing activated oncogenes experience apoptotic caspase activation, and that Akt1 and dCIZ1 are required for their survival and overgrowth. Thus, survival following executioner caspase activation is a normal tissue repair mechanism usurped to promote oncogene-driven overgrowth.


Assuntos
Carcinogênese/genética , Caspases/metabolismo , Sobrevivência Celular , Proteínas Proto-Oncogênicas c-akt/metabolismo , Animais , Apoptose , Morte Celular , Drosophila/genética , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Humanos , Proteínas Nucleares , Oncogenes , Interferência de RNA , Fatores de Transcrição , Asas de Animais , Dedos de Zinco
19.
Artigo em Inglês | MEDLINE | ID: mdl-33198931

RESUMO

Lung cancer and chronic obstructive pulmonary disease (COPD) are closely linked diseases. In Xuanwei, China, the extremely high incidence and mortality rates of lung cancer and COPD are associated with exposure to household smoky coal burning. Previous studies found that telomere length was related to lung disease. The objective of this study is to investigate the relationship of peripheral blood leukocyte telomere length to both lung cancer and COPD, as well as indoor coal smoke exposure in Xuanwei. We measured telomere length using quantitative polymerase chain reaction (qPCR) in peripheral blood leukocytes of 216 lung cancer patients, 296 COPD patients, and 426 healthy controls from Xuanwei. The telomere length ratios (mean ± SD) in patients with lung cancer (0.76 ± 0.35) and COPD (0.81 ± 0.35) were significantly shorter than in that of controls (0.95 ± 0.39). Individuals with the shortest tertile telomere length had 3.90- and 4.54-fold increased risks of lung cancer and COPD, respectively, compared with individuals with the longest tertile telomere length. No correlation was found between telomere length and pack-years of smoking. In healthy subjects, coal smoke exposure level affected telomere length. Lung function was positively and negatively associated with telomere length and environmental exposure, respectively, when combination the control and COPD groups. The result suggests that shortened telomere length in peripheral blood leukocytes was associated with lung cancer and COPD and might be affected by coal smoke exposure level in Xuanwei. Whether variation in telomere length caused by environmental exposure has a role in lung cancer and COPD development and exacerbation needs further research.


Assuntos
Poluição do Ar em Ambientes Fechados/análise , Leucócitos/metabolismo , Neoplasias Pulmonares/genética , Doença Pulmonar Obstrutiva Crônica/genética , Encurtamento do Telômero/genética , Telômero/genética , Idoso , Poluição do Ar em Ambientes Fechados/efeitos adversos , China/epidemiologia , Carvão Mineral , Feminino , Humanos , Incidência , Neoplasias Pulmonares/epidemiologia , Neoplasias Pulmonares/etiologia , Masculino , Pessoa de Meia-Idade , Doença Pulmonar Obstrutiva Crônica/epidemiologia , Doença Pulmonar Obstrutiva Crônica/etiologia , Medição de Risco/métodos , Medição de Risco/estatística & dados numéricos , Fatores de Risco , Fumaça
20.
Science ; 370(6519): 987-990, 2020 11 20.
Artigo em Inglês | MEDLINE | ID: mdl-33214282

RESUMO

Moving cells can sense and respond to physical features of the microenvironment; however, in vivo, the significance of tissue topography is mostly unknown. Here, we used Drosophila border cells, an established model for in vivo cell migration, to study how chemical and physical information influences path selection. Although chemical cues were thought to be sufficient, live imaging, genetics, modeling, and simulations show that microtopography is also important. Chemoattractants promote predominantly posterior movement, whereas tissue architecture presents orthogonal information, a path of least resistance concentrated near the center of the egg chamber. E-cadherin supplies a permissive haptotactic cue. Our results provide insight into how cells integrate and prioritize topographical, adhesive, and chemoattractant cues to choose one path among many.


Assuntos
Movimento Celular , Drosophila melanogaster/citologia , Drosophila melanogaster/crescimento & desenvolvimento , Oócitos/fisiologia , Animais , Caderinas/metabolismo , Fatores Quimiotáticos/metabolismo , Imagem Molecular , Oócitos/metabolismo
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