RESUMO
African swine fever (ASF), caused by the African swine fever virus (ASFV), is a transboundary infectious disease of domestic pigs and wild boars, resulting in significant swine production losses. Currently, no effective commercial ASF vaccines or therapeutic options are available. A previous study has shown that deletions of ASFV MGF110-9L and MGF505-7R genes (ASFV-Δ110-9L/505-7R) attenuated virulence in pigs and provided complete protection against parental lethal ASFV CN/GS/2018 (wild-type ASFV [ASFV-WT]) challenge, but the underlying mechanism is unclear. This study found that ASFV-Δ110-9L/505-7R weakened TBK1 degradation compared with ASFV-WT through RNA sequencing (RNA-seq) and Western blotting analyses. Furthermore, we confirmed that ASFV-Δ110-9L/505-7R blocked the degradation of TBK1 through the autophagy pathway. We also identified that the downregulation of an autophagy-related protein PIK3C2B was involved in the inhibition of TBK1 degradation induced by ASFV-Δ110-9L/505-7R. Additionally, we also confirmed that PIK3C2B promoted ASFV-Δ110-9L/505-7R replication in vitro. Together, this study elucidated a novel mechanism of virulence change of ASFV-Δ110-9L/505-7R, revealing a new mechanism of ASF live attenuated vaccines (LAVs) and providing theoretical guidance for the development of ASF vaccines. IMPORTANCE African swine fever (ASF) is a contagious and lethal hemorrhagic disease of pigs caused by the African swine fever virus (ASFV), leading to significant economic consequences for the global pig industry. The development of an effective and safe ASF vaccine has been unsuccessful. Previous studies have shown that live attenuated vaccines (LAVs) of ASFV are the most effective vaccine candidates to prevent ASF. Understanding the host responses caused by LAVs of ASFV is important in optimizing vaccine design and diversifying the resources available to control ASF. Recently, our laboratory found that the live attenuated ASFV-Δ110-9L/505-7R provided complete protection against parental ASFV-WT challenge. This study further demonstrated that ASFV-Δ110-9L/505-7R inhibits TBK1 degradation mediated by an autophagy activator PIK3C2B to increase type I interferon production. These results revealed an important mechanism for candidate vaccine ASFV-Δ110-9L/505-7R, providing strategies for exploring the virulence of multigene-deleted live attenuated ASFV strains and the development of vaccines.
Assuntos
Vírus da Febre Suína Africana , Febre Suína Africana , Interferon Tipo I , Vacinas Virais , Animais , Febre Suína Africana/prevenção & controle , Vírus da Febre Suína Africana/genética , Interferon Tipo I/metabolismo , Sus scrofa , Suínos , Vacinas Atenuadas , Genes ViraisRESUMO
Aronia melanocarpa fruit contains a variety of active ingredients, such as phenolic acids, anthocyanins, proanthocyanidins, etc. Relevant in vivo and in vitro studies have concluded that it has beneficial effects in terms of treating dyslipidemia, hypertension, glucose metabolism disorders, etc. This article discusses the nutritional value and food processing of Aronia melanocarpa and reviews the chemical components of Aronia melanocarpa and the pharmacological activities of related substances in order to summarize the chemical characteristics of the fruit and its development prospects. The process optimization of juice production, the impact of antioxidant capacity, and the comprehensive utilization of pomace in feed are discussed. This article provides a reference for future comprehensive application research and product development of Aronia melanocarpa.
Assuntos
Photinia , Proantocianidinas , Antocianinas/farmacologia , Photinia/química , Antioxidantes/farmacologia , Antioxidantes/química , Extratos Vegetais/farmacologia , Extratos Vegetais/químicaRESUMO
Luminescent polymer nanomaterials not only have the characteristics of various types of luminescent functional materials and a wide range of applications, but also have the characteristics of good biocompatibility and easy functionalization of polymer nanomaterials. They are widely used in biomedical fields such as bioimaging, biosensing, and drug delivery. Designing and constructing new controllable synthesis methods for multifunctional fluorescent polymer nanomaterials with good water solubility and excellent biocompatibility is of great significance. Exploring efficient functionalization methods for luminescent materials is still one of the core issues in the design and development of new fluorescent materials. With this in mind, this review first introduces the structures, properties, and synthetic methods regarding fluorescent polymeric nanomaterials. Then, the functionalization strategies of fluorescent polymer nanomaterials are summarized. In addition, the research progress of multifunctional fluorescent polymer nanomaterials for bioimaging is also discussed. Finally, the synthesis, development, and application fields of fluorescent polymeric nanomaterials, as well as the challenges and opportunities of structure-property correlations, are comprehensively summarized and the corresponding perspectives are well illustrated.
Assuntos
Nanoestruturas , Polímeros , Polímeros/química , Nanoestruturas/química , Corantes , Sistemas de Liberação de MedicamentosRESUMO
BACKGROUND: Yersinia ruckeri is a pathogen that can cause enteric redmouth disease in salmonid species, damaging global production of economically important fish including rainbow trout (Oncorhynchus mykiss). Herein, we conducted the transcriptomic profiling of spleen samples from rainbow trout at 24 h post-Y. ruckeri infection via RNA-seq in an effort to more fully understand their immunological responses. RESULTS: We identified 2498 differentially expressed genes (DEGs), of which 2083 and 415 were up- and down-regulated, respectively. We then conducted a more in-depth assessment of 78 DEGs associated with the immune system including CCR9, CXCL11, IL-1ß, CARD9, IFN, TNF, CASP8, NF-κB, NOD1, TLR8α2, HSP90, and MAPK11, revealing these genes to be associated with 20 different immunological KEGG pathways including the Cytokine-cytokine receptor interaction, Toll-like receptor signaling, RIG-I-like receptor signaling, NOD-like receptor signaling, and MAPK signaling pathways. Additionally, the differential expression of 8 of these DEGs was validated by a qRT-PCR approach and their immunological importance was then discussed. CONCLUSIONS: Our findings provide preliminary insight on molecular mechanism underlying the immune responses of rainbow trout following Y. ruckeri infection and the base for future studies of host-pathogen interactions in rainbow trout.
Assuntos
Doenças dos Peixes , Oncorhynchus mykiss , Yersiniose , Animais , Perfilação da Expressão Gênica , Imunidade/genética , Oncorhynchus mykiss/genética , Baço , Yersiniose/genética , Yersiniose/veterinária , Yersinia ruckeriRESUMO
In the present study, the anti-inflammation effect of Phellinus igniarius extract was detected on an in vitro model of RAW 264.7 cells stimulated using sodium urate. In this cell model, the content changes of inflammatory cytokines, intercellular adhesion molecule-1, and interleukin-1 beta, in cell culture supernatants were detected using an enzyme-linked immunosorbent assay. The xanthine oxidase inhibitory activity of P. igniarius extracts was determined using a microplate reader. Furthermore, in order to identify the active compounds of P. igniarius, ultrafiltration liquid chromatography mass spectrometry was utilized to screen xanthine oxidase inhibitors from the extract. Our results showed that in the presence of P. igniarius extract, the expressions of interleukin-1 beta and intercellular adhesion molecule-1 decreased (p < 0.01 and p < 0.05, respectively) compared to that in the control group. The extract effective inhibited the xanthine oxidase activity. Finally, seven compounds were screened and identified as potential xanthine oxidase inhibitors from P. igniarius. Taken together, these results demonstrate a potential anti-inflammation bioactivity of P. igniarius in vitro, providing a basis for further in vivo research for the prevention and treatment of gout.
Assuntos
Cromatografia Líquida/métodos , Supressores da Gota/análise , Espectrometria de Massas/métodos , Phellinus/química , Ultrafiltração/métodos , Animais , Técnicas In Vitro , Camundongos , Extratos Vegetais/farmacologia , Células RAW 264.7 , Xantina Oxidase/antagonistas & inibidoresRESUMO
Stomach cancer is the fourth most common cancer worldwide. Identification of novel molecular therapeutic targets and development of novel treatments are critical. Against a panel of gastric carcinoma cell lines, the activity of 2-(4-amino-3-methylphenyl)-5-fluorobenzothiazole (5F 203) was investigated. Adopting RT-PCR, Western blot and immunohistochemical techniques, we sought to determine molecular pharmacodynamic (PD) markers of sensitivity and investigate arylhydrocarbon (AhR) receptor-mediated signal transduction activation by 5F 203. Potent (IC50 ≤ 0.09 µmol/L), selective (>250-fold) in vitro antitumour activity was observed in MKN-45 and AGS carcinoma cells. Exposure of MKN-45 cells to 5F 203 triggered cytosolic AhR translocation to nuclei, inducing CYP1A1 (>50-fold) and CYP2W1 (~20-fold) transcription and protein (CYP1A1 and CYP2W1) expression. G2/M arrest and γH2AX expression preceded apoptosis, evidenced by PARP cleavage. In vivo, significant (P < .01) 5F 203 efficacy was observed against MKN-45 and AGS xenografts. In mice-bearing 5F 203-sensitive MKN-45 and 5F 203-insensitive BGC-823 tumours in opposite flanks, CYP1A1, CYP2W1 and γH2AX protein in MKN-45 tumours only following treatment of mice with 5F 203 (5 mg/kg) revealed PD biomarkers of sensitivity. 5F 203 evokes potent, selective antitumour activity in vitro and in vivo in human gastric cancer models. It triggers AhR signal transduction, CYP-catalysed bioactivation to electrophilic species causing lethal DNA double-strand breaks exclusively in sensitive cells. 5F 203 represents a novel therapeutic agent with a mechanism of action distinct from current clinical drugs, exploiting novel molecular targets pertinent to gastric tumourigenesis: AhR, CYP1A1 and CYP2W1. PD markers of 5F 203 sensitivity that could guide patient selection have been identified.
Assuntos
Antineoplásicos/uso terapêutico , Receptores de Hidrocarboneto Arílico/metabolismo , Transdução de Sinais , Neoplasias Gástricas/tratamento farmacológico , Neoplasias Gástricas/metabolismo , Tiazóis/uso terapêutico , Animais , Antineoplásicos/química , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Apoptose/genética , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sistema Enzimático do Citocromo P-450/genética , Sistema Enzimático do Citocromo P-450/metabolismo , Dano ao DNA , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Espaço Intracelular/metabolismo , Camundongos Endogâmicos BALB C , Camundongos Nus , Neoplasias Gástricas/genética , Neoplasias Gástricas/patologia , Tiazóis/química , Tiazóis/farmacologiaRESUMO
Drug discovery from complex mixtures, like Chinese herbs, is challenging and extensive false positives make it difficult to obtain compounds with anti-Alzheimer's activity. In this study, a continuous method comprised of accelerated solvent extraction coupled with online two-dimensional countercurrent chromatography was developed for the efficient, scaled-up extraction and separation of six bioactive compounds from Citrus limon peels: neoeriocitrin, isonaringin, naringin, hesperidin, neohesperidin, and limonin. These active compounds were isolated and purified from the raw plant materials by two-dimensional countercurrent chromatography separation via two sets of an n-hexane/n-butanol/methanol/water solvent system: 0.23:1.00:0.25:1.13 and 0.47:1.00:0.38:1.46, v/v/v/v. The compounds were collected in yields of 0.22, 0.25, 0.10, 0.31, 0.29, and 0.28 mg/g, respectively, with purities of 95.79, 96.47, 97.69, 97.22, 98.11, and 98.82%, respectively. Subsequently, a simple and efficient in vitro method was developed for rapidly evaluating the acetylcholinesterase inhibitory activities of six bioactive components. Furthermore, the PC12 cell model and the in vitro metabolism of cytochromes P450 were employed to verify the monomers obtained from the continuous method. The results demonstrated that these six bioactive extracts from the C. limon peels were strong acetylcholinesterase inhibitors.
Assuntos
Citrus/química , Distribuição Contracorrente/métodos , Flavanonas/isolamento & purificação , Extratos Vegetais/química , Animais , Inibidores da Colinesterase/isolamento & purificação , Inibidores da Colinesterase/farmacologia , Sistema Enzimático do Citocromo P-450/efeitos dos fármacos , Sistema Enzimático do Citocromo P-450/metabolismo , Dissacarídeos/isolamento & purificação , Dissacarídeos/farmacologia , Flavanonas/farmacologia , Flavonoides/isolamento & purificação , Flavonoides/farmacologia , Hesperidina/análogos & derivados , Hesperidina/isolamento & purificação , Hesperidina/farmacologia , Células PC12/efeitos dos fármacos , Células PC12/metabolismo , Ratos , Solventes/químicaRESUMO
As a major diarrheagenic human pathogen, enterohemorrhagic Escherichia coli (EHEC) produce attaching and effacing (A/E) lesions, characterized by the formation of actin pedestals, on mammalian cells. A bacterial T3SS effector NleL from EHEC O157:H7 was recently shown to be a HECT-like E3 ligase in vitro, but its biological functions and host targets remain elusive. Here, we report that NleL is required to effectively promote EHEC-induced A/E lesions and bacterial infection. Furthermore, human c-Jun NH2-terminal kinases (JNKs) were identified as primary substrates of NleL. NleL-induced JNK ubiquitylation, particularly mono-ubiquitylation at the Lys 68 residue of JNK, impairs JNK's interaction with an upstream kinase MKK7, thus disrupting JNK phosphorylation and activation. This subsequently suppresses the transcriptional activity of activator protein-1 (AP-1), which modulates the formation of the EHEC-induced actin pedestals. Moreover, JNK knockdown or inhibition in host cells complements NleL deficiency in EHEC infection. Thus, we demonstrate that the effector protein NleL enhances the ability of EHEC to infect host cells by targeting host JNK, and elucidate an inhibitory role of ubiquitylation in regulating JNK phosphorylation.
Assuntos
Aderência Bacteriana , Escherichia coli Êntero-Hemorrágica/fisiologia , Infecções por Escherichia coli/enzimologia , Infecções por Escherichia coli/microbiologia , Proteínas de Escherichia coli/metabolismo , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Motivos de Aminoácidos , Escherichia coli Êntero-Hemorrágica/genética , Infecções por Escherichia coli/genética , Proteínas de Escherichia coli/genética , Células HeLa , Humanos , Proteínas Quinases JNK Ativadas por Mitógeno/química , Proteínas Quinases JNK Ativadas por Mitógeno/genética , MAP Quinase Quinase 7/genética , MAP Quinase Quinase 7/metabolismo , Fosforilação , Fator de Transcrição AP-1/genética , Fator de Transcrição AP-1/metabolismo , Ubiquitina-Proteína Ligases/genética , UbiquitinaçãoRESUMO
Nonsteroidal anti-inflammatory drugs reportedly reduce the risk of developing cancer. One mechanism by which they reduce carcinogenesis involves the inhibition of the activity of cyclooxygenase-2, an enzyme that is overexpressed in various cancer tissues. Its overexpression increases cell proliferation and inhibits apoptosis. However, selected cyclooxygenase-2 inhibitors can also act through cyclooxygenase-independent mechanisms. In this study, using ultrafiltration, enzyme-immobilized magnetic beads, high-performance liquid chromatography, and electrospray-ionization mass spectrometry, several isoflavonoids in Trifolium pratense L. extracts were screened and identified. Semi-preparative high-performance liquid chromatography and high-speed counter-current chromatography were then applied to separate the active constituents. Using these methods, seven major compounds were identified in Trifolium pratense L. As cyclooxygenase-2 inhibitors: rothindin, ononin, daidzein, trifoside, pseudobaptigenin, formononetin, and biochanin A, which were then isolated with >92% purity. This is the first report of the presence of potent cyclooxygenase-2 inhibitors in Trifolium pratense L. extracts. The results of this study demonstrate that the systematic isolation of bioactive components from Trifolium pratense L., by using ultrafiltration, enzyme-immobilized magnetic beads, semi-preparative high-performance liquid chromatography, and high-speed counter-current chromatography, represents a feasible and efficient technique that could be extended for the identification and isolation of other enzyme inhibitors.
Assuntos
Inibidores de Ciclo-Oxigenase 2/isolamento & purificação , Genisteína/isolamento & purificação , Glucosídeos/isolamento & purificação , Isoflavonas/isolamento & purificação , Cromatografia Líquida de Alta Pressão , Distribuição Contracorrente , Inibidores de Ciclo-Oxigenase 2/química , Enzimas Imobilizadas/química , Enzimas Imobilizadas/metabolismo , Genisteína/química , Glucosídeos/química , Isoflavonas/química , Fenômenos Magnéticos , Trifolium/química , UltrafiltraçãoRESUMO
Nonsteroidal anti-inflammatory drugs appear to reduce the risk of developing cancer. One mechanism through which nonsteroidal anti-inflammatory drugs act to prevent carcinogenesis is inhibition of the activity of the enzyme cyclooxygenase-2. The cyclooxygenase-2 inhibitors are widely used to reduce the risk of developing cancer. Natural products are considered to be a promising source of several novel cyclooxygenase-2 inhibitors. Ultrafiltration with liquid chromatography and mass spectrometry is an efficient method that can be applied to rapidly screen and identify the ligands from the barks of Phellodendron amurense Ruprecht. A continuous online method comprised of pressurized liquid extraction, countercurrent chromatography, and semi-preparative liquid chromatography was developed for the efficient scaled-up production of eight compounds with high purities. The bioactivities of the separated compounds were assessed by an in vitro enzyme inhibition assay. The use of bioactivity screening method combined with preparation method of bioactive compounds and an in vitro enzyme inhibition assay facilitated the efficient screening and isolation of the cyclooxygenase-2 inhibitors from complex samples. This could be used as an efficient method for the large-scale production of functional ingredients.
Assuntos
Inibidores de Ciclo-Oxigenase 2/análise , Inibidores de Ciclo-Oxigenase 2/isolamento & purificação , Phellodendron/química , Casca de Planta/química , Anti-Inflamatórios não Esteroides/análise , Anti-Inflamatórios não Esteroides/isolamento & purificação , Cromatografia Líquida , Distribuição Contracorrente , Humanos , Extratos Vegetais/química , Reprodutibilidade dos Testes , Solventes , Espectrometria de Massas em Tandem , UltrafiltraçãoRESUMO
Natural products have become one of the most important resources for discovering novel xanthine oxidase inhibitors, which are commonly employed in the treatment of hyperuricemia and gout. However, to date, few reports exist regarding the use of monoterpene glycosides as xanthine oxidase inhibitors. Thus, we herein report the use of ultrafiltration coupled with liquid chromatography in the screening of monoterpene glycoside xanthine oxidase inhibitors from the extract of Paeonia lactiflora (P. lactiflora), and both high-performance counter-current chromatography and medium-pressure liquid chromatography were employed to separate the main constituents. Furthermore, the xanthine oxidase inhibitory activities and the mechanisms of inhibition of the isolated compounds were evaluated using a multi-mode microplate reader by Molecular Devices. As a result, three monoterpene glycosides were separated by combined high-performance counter-current chromatography and medium-pressure liquid chromatography in purities of 90.4, 98.0, and 86.3%, as determined by liquid chromatography. These three compounds were identified as albiflorin, paeoniflorin, and 1-O-ß-á´ -glucopyranosyl-8-O-benzoylpaeonisuffrone by electrospray ionization tandem mass spectrometry, and albiflorin and paeoniflorin were screened as potential xanthine oxidase inhibitors by ultrafiltration with liquid chromatography. The evaluation results of xanthine oxidase inhibitory activity corresponded with the screening results, as only albiflorin and paeoniflorin exhibited xanthine oxidase inhibitory activity.
Assuntos
Inibidores Enzimáticos/isolamento & purificação , Glicosídeos/isolamento & purificação , Monoterpenos/isolamento & purificação , Paeonia/química , Xantina Oxidase/antagonistas & inibidores , Cromatografia Líquida de Alta Pressão , Cromatografia Líquida , Espectrometria de Massas por Ionização por ElectrosprayRESUMO
In the present study, we investigated the protective mechanism of paeoniflorin (PF), a monoterpene glycoside extracted from Radix Paeoniae alba roots, on MPP(+)-induced neurotoxicity in cultured rat pheochromocytoma cells (PC12). Our work included examination of cell viability assessment, amounts of released lactic dehydrogenase (LDH), intracellular Ca(2+) concentration, cell apoptosis, mitochondrial membrane potential, caspase-3 activity, and expression profiling of two apoptosis-related genes (Bcl-2 and Bax). It was shown that, PF functioned as an MPP(+) antagonist, being able to suppress apoptosis, decrease LDH release and Ca(2+) concentration, attenuate membrane potential collapse and, inhibit caspase-3 activation, decrease in Bax/Bcl-2 ratio. These observations suggest that PF could protect PC12 cells against MPP(+)-induced injury and the mechanism PF's neuroprotective effect was closely associated with Bcl-2 up-regulation and Bax down-regulation. PF has neuroprotective effects on MPP(+)-induced apoptosis in PC12 cells via regulating mitochondrial membrane potential and Bcl-2/Bax/caspase-3 signaling pathways, and this new insight will help develop a PF-based therapeutic strategy for treatmenting neurodegenerative diseases and injury.
Assuntos
1-Metil-4-fenilpiridínio/toxicidade , Sobrevivência Celular/fisiologia , Glucosídeos/farmacologia , Monoterpenos/farmacologia , Fármacos Neuroprotetores/farmacologia , Animais , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Células PC12 , RatosRESUMO
Heat-labile enterotoxin (LT) of enterotoxigenic Escherichia coli (ETEC) is one of the major virulence factors for causing diarrhea in piglets, and LT is a strong immunogen. Thus, LT represents an important target for development of vaccines and diagnostic tests. In this study, bioinformatic tools were used to predict six antigenic B cell epitopes in the B subunit of LT protein (LTB) of ETEC strains. Then, seven antigenic B cell epitopes of LTB were identified by polyclonal antisera (polyclonal antibody (PAb)) using a set of LTB-derived peptides expressed as maltose-binding protein (MBP) fusion protein. In addition, one LTB-specific monoclonal antibody (MAb) was generated and defined its corresponding epitope as mentioned above. This MAb was able to specifically bind with native LT toxin and has no cross-reaction with LT-II (type II heat-labile enterotoxin), Stx1 (Shiga toxin I), Stx2 (Shiga toxin II), STa (heat-stable enterotoxin I), and STb (heat-stable enterotoxin II) toxins. Further, this MAb was able to interrupt LT toxin specific binding to GM1 receptor, indicating that the corresponding epitope is the specific binding region to GM1 receptor. Moreover, in vitro and in vivo assay showed that the MAb was able to neutralize the native LT toxin. Diarrheal suckling pigs challenged with LT-positive ETEC strain recovered when an enema with this purified MAb was administered. This study will provide the foundation for further studies about the interaction between LT toxin and GM1 receptor and about the developing of epitope-based vaccines and specific therapeutic agent.
Assuntos
Anticorpos Antibacterianos/imunologia , Anticorpos Neutralizantes/imunologia , Toxinas Bacterianas/imunologia , Enterotoxinas/imunologia , Epitopos de Linfócito B/imunologia , Proteínas de Escherichia coli/imunologia , Animais , Anticorpos Monoclonais/imunologia , Anticorpos Monoclonais/isolamento & purificação , Toxinas Bacterianas/genética , Biologia Computacional , Diarreia/terapia , Enema , Enterotoxinas/genética , Epitopos de Linfócito B/genética , Infecções por Escherichia coli/terapia , Infecções por Escherichia coli/veterinária , Proteínas de Escherichia coli/genética , Imunização Passiva/métodos , Testes de Neutralização , Ligação Proteica , Receptores de Superfície Celular/metabolismo , Suínos , Doenças dos Suínos/terapia , Resultado do TratamentoRESUMO
Previous epidemiological study showed that most of the porcine enterotoxin Escherichia coli (ETEC) strains harbor multiple enterotoxins but lack any of the fimbriae or non-fimbrial adhesion genes. Therefore, effective ETEC vaccines need to aim directly at all the enterotoxin antigens. The objective of this study was to evaluate the simultaneous immune effect of two live attenuated E. coli strains expressing LTR192G-STaA13Q and LTR192G-STb fusion immunogen, respectively. The results showed that both local mucosal and systemic immune responses against LT, STa, STb, and F41 were induced in BALB/c mice immunized orally with the recombinant E. coli strains ER-A and ER-B simultaneously. In addition, results of cellular immune responses showed that stimulation index (SI) values of immunized mice were significantly higher than control mice (P < 0.05) and a marked shift toward type-2 helper T lymphocyte (Th 2) immunity. Moreover, the induced antibodies demonstrated neutralizing effects on LT, STa, and STb producing E. coli infection. These data indicated that the use of recombinant E. coli ER-A and ER-B could be a valuable strategy for future polyvalent vaccine development of ETEC.
Assuntos
Toxinas Bacterianas/imunologia , Vacinas Bacterianas/imunologia , Enterotoxinas/imunologia , Proteínas de Escherichia coli/imunologia , Escherichia coli/imunologia , Imunização/métodos , Animais , Anticorpos Antibacterianos/sangue , Anticorpos Neutralizantes/sangue , Antígenos de Bactérias/genética , Antígenos de Bactérias/imunologia , Toxinas Bacterianas/genética , Vacinas Bacterianas/administração & dosagem , Enterotoxinas/genética , Escherichia coli/genética , Proteínas de Escherichia coli/genética , Camundongos , Camundongos Endogâmicos BALB C , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/imunologia , Linfócitos T/imunologia , Vacinas Atenuadas/administração & dosagem , Vacinas Atenuadas/imunologia , Vacinas Sintéticas/administração & dosagem , Vacinas Sintéticas/imunologiaRESUMO
Enter toxigenic Escherichia coli (ETEC) is a major pathogen of swine industry that can have a substantial impact on morbidity and mortality. Therefore, it is necessary to develop effective vaccines for the prevention of ETEC infection. Live attenuated bacteria delivery system are effective tools for mucosal immunization. The purpose of this study was to construct a novel delivery system that can present the LTR192G-STb fusion protein as oral vaccine candidate. Firstly, the PRPL-mKate2 fluorescent cassette was inserted into the genome (yaiT pseudogene) of an attenuated E. coli by homologous recombination methods to construct the delivery system O142(yaiT::PRPL-mKate2). Secondly, the oral vaccine O142(yaiT:: LT192-STb) (ER-B) was derived for replacing the PRPL-mKate2 by LT192-STb fusion gene, and then it was tested for its feasibility as oral vaccine candidate. Subsequently, BALB/c mice were orogastrically immunized with ER-B. Results showed that mice orally immunized with ER-B produced high levels of specific IgA and IgG antibodies. The induced antibodies demonstrated neutralizing effects to enter toxins LT and STb. In addition, results of cellular immune responses showed that stimulation index values of immunized mice were significantly higher than the control group (P < 0.05) and with a marked shift towards Th 2 immunity. These data indicated that the recombinant E. coli ER-B could be a valuable candidate of future vaccines against ETEC infection.
Assuntos
Toxinas Bacterianas/imunologia , Enterotoxinas/imunologia , Proteínas de Escherichia coli/imunologia , Vacinas contra Escherichia coli/imunologia , Escherichia coli/imunologia , Fluorescência , Genes Reporter , Administração Oral , Animais , Anticorpos Antibacterianos/análise , Anticorpos Antibacterianos/sangue , Anticorpos Neutralizantes/análise , Anticorpos Neutralizantes/sangue , Toxinas Bacterianas/genética , Proliferação de Células , Enterotoxinas/genética , Ensaio de Imunoadsorção Enzimática , Escherichia coli/genética , Proteínas de Escherichia coli/genética , Vacinas contra Escherichia coli/administração & dosagem , Vacinas contra Escherichia coli/genética , Fezes/química , Imunoglobulina A/análise , Imunoglobulina A/sangue , Imunoglobulina G/análise , Imunoglobulina G/sangue , Camundongos Endogâmicos BALB C , Soro/química , Linfócitos T/imunologia , Vacinas Atenuadas/administração & dosagem , Vacinas Atenuadas/genética , Vacinas Atenuadas/imunologia , Vacinas Sintéticas/administração & dosagem , Vacinas Sintéticas/genética , Vacinas Sintéticas/imunologiaRESUMO
Live attenuated bacteria delivered orally are interesting tools for mucosal immunization. The objective of this study was to construct a novel counter-selection platform based on an attenuated wild-type Escherichia coli (E. coli) strain and to utilize it for the delivery of LTR192G-STaA13Q fusion protein as an oral vaccine. First, a counter-selectable marker, namely, PRPL-Kil, was inserted into an attenuated wild-type E. coli strain through the use of the red and G-DOC homologous recombination systems to construct the counter-selection platform, and PRPL-Kil was subsequently replaced by the LT192-STa13 fusion gene to construct the oral vaccine O142 (yaiT::LT192-STa13) (ER-A). Subsequently, BALB/c mice were orogastrically inoculated with ER-A. Our results showed that ER-A could induce the production of specific IgA and IgG against fimbriae (F41) and enterotoxins (LT and STa), with neutralizing activity in BALB/c mice. In addition, assays of cellular immune responses showed that the stimulation index (SI) values of immunized mice were significantly higher than those of control mice (P<0.05), and revealed a marked shift toward Th2-mediated immunity. These findings suggest that ER-A is a suitable candidate for an oral vaccine strain to protect animals from enter toxigenic Escherichia coli (ETEC) infection.
Assuntos
Infecções por Escherichia coli/prevenção & controle , Vacinas contra Escherichia coli/imunologia , Escherichia coli/imunologia , Imunidade nas Mucosas , Administração Oral , Animais , Anticorpos Antibacterianos/sangue , Anticorpos Antibacterianos/imunologia , Anticorpos Neutralizantes/sangue , Anticorpos Neutralizantes/imunologia , Antígenos de Bactérias/imunologia , Enterotoxinas/imunologia , Escherichia coli/genética , Infecções por Escherichia coli/imunologia , Vacinas contra Escherichia coli/administração & dosagem , Feminino , Fímbrias Bacterianas/imunologia , Imunoglobulina A/imunologia , Imunoglobulina G/imunologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Proteínas Recombinantes/genética , Proteínas Recombinantes/imunologia , Vacinas Atenuadas/administração & dosagem , Vacinas Atenuadas/imunologiaRESUMO
Many approaches for generating large quantities of recombinant protein in Escherichia coli fuse the protein of interest to a protein tag to enhance solubility and improve recovery. However, the fusion tags can confound downstream applications, as the fusion partner can alter the structure and biological activity of the recombinant protein and proteolytic removal of the fusion tags can be expensive. Here we describe a new system for production of native proteins in E. coli that allows for removal of the fusion tag via intracellular self-cleavage by the human rhinovirus 3C (HRV3C) protease. This system allows for parallel cloning of target protein coding sequences into six different expression vectors, each with a different fusion partner tag to enhance solubility during induction. Temperature-regulated expression of the HRV3C protease allows for intracellular removal of the fusion tag following induction, and the liberated recombinant protein can be purified by affinity chromatography by virtue of a short six-histidine tag. This system will be an attractive approach for the expression and purification of recombinant proteins free of solubility-enhancing fusion tags, and should be amenable to high-throughput applications.
Assuntos
Clonagem Molecular/métodos , Escherichia coli/metabolismo , Proteínas Recombinantes de Fusão/metabolismo , Proteases Virais 3C , Cisteína Endopeptidases/genética , Cisteína Endopeptidases/metabolismo , Escherichia coli/genética , Proteínas de Fluorescência Verde/genética , Proteínas Recombinantes de Fusão/genética , Solubilidade , Proteínas Virais/genética , Proteínas Virais/metabolismoRESUMO
CONTEXT: Mogroside V, a compound isolated from Momordica grosvenori Swingle, which belongs to the Cucurbitaceae, is a traditional Chinese medicine reported to have anti-inflammatory potential in murine macrophages and a murine ear edema model. OBJECTIVE: To investigate the effects and mechanisms of action of this compound in a model of acute lung injury (ALI) induced by lipopolysaccharides (LPS). MATERIALS AND METHODS: Female BALB/c mice were treated with commercial mogroside V (2.5, 5 and 10 mg/kg) for 1 h prior to intranasal injection of LPS (10 µg in 50 µl). After 12 h, airway inflammation in the ALI model was determined by the wet/dry weight (W/D) ratio, myeloperoxidase (MPO) activity of lung tissue, leukocyte recruitment and cytokine levels in the bronchoalveolar lavage fluid (BALF). Additionally, lung tissue was examined by histology and western blotting to investigate the changes in pathology and the signalling in the presence and absence of mogroside V. RESULTS: Mogroside V at 5 and 10 mg/kg inhibited airway inflammation induced by LPS as measured by the decrease in the histological changes (44 and 67.3% reduction in lung injury score, respectively), a 28.9 and 55.3% reduction in lung MPO activity, and inflammatory cell counts, interleukin-1ß (IL-1ß, 382 and 280 pg/ml, respectively), IL-6 (378 and 232 pg/ml, respectively) and tumor necrosis factor-α (TNF-α, 12.5 and 7.8 ng/ml, respectively) levels in the BALF. Additionally, mogroside V treatment reduced the activation of cyclooxygenase 2 (COX-2), inducible NO synthase (iNOS), and the nuclear factor (NF)-κB. DISCUSSIONS AND CONCLUSIONS: Together, these data suggest that mogroside V has the potential to protect against LPS-induced airway inflammation in a model of ALI.
Assuntos
Lesão Pulmonar Aguda/induzido quimicamente , Lesão Pulmonar Aguda/prevenção & controle , Lipopolissacarídeos/toxicidade , Triterpenos/uso terapêutico , Lesão Pulmonar Aguda/patologia , Animais , Feminino , Camundongos , Camundongos Endogâmicos BALB C , Substâncias Protetoras/uso terapêutico , Distribuição AleatóriaRESUMO
Our work aimed to investigate the interactive roles of transforming growth factor ß1 (TGF-ß1), ubiquitin-specific-processing protease 7 (USP7), and Yes-associated protein (YAP) in ferroptosis during sepsis-secondary acute lung injury (ALI). Our study demonstrated that ferroptosis was aggravated by TGF-ß1 in both cellular and animal models of acute lung injury. Additionally, YAP upregulated glutathione peroxidase 4 (GPX4) and SLC7A11 by regulating the binding of TEAD4 to GPX4/SLC7A11 promoters. Furthermore, large tumor suppressor kinase 1 (LATS1) knockdown resulted in YAP expression stimulation, while USP7 downregulated YAP via deubiquitinating and stabilizing LATS1/2. YAP overexpression or USP7/LATS1 silencing reduced ferroptosis process, which regulated YAP through a feedback loop. However, TGF-ß1 annulled the repression of ferroptosis by YAP overexpression or LATS1/USP7 knockdown. By elucidating the molecular interactions between TGF-ß1, USP7, LATS1/2, and YAP, we identified a new regulatory axis of ferroptosis in sepsis-secondary ALI. Our study sheds light on the pathophysiology of ferroptosis and proposes a potential therapeutic approach for sepsis-induced ALI.
RESUMO
In this study, we outlined the green synthesis of Zinc oxide nanoparticles (ZnO NPs) using the plant-mediated method. Employing the nitrate derivative of Zinc and the extract from the native medicinal plant, Ottonia anisum, the nanoparticles were effectively produced. After obtaining a yellow-colored paste, it was meticulously dried, gathered, and set aside for subsequent examination. The UV-visible spectrometry analysis indicated an absorption peak at 320 nm, which is indicative of ZnO NPs. Characterization techniques, such as XRD and HR-TEM, confirmed the existence of agglomerated ZnO NPs with an average diameter of 40 nm. Through EDS analysis, distinct energy signals for both Zinc and Oxygen were observed, confirming their composition. Furthermore, FT-IR spectroscopy highlighted an absorption peak for Zn-O bonding in the range of 400 to 600 cm -1 . Further, we employed three distinct pain models in mice to evaluate the influence of ZnO NPs on the nociceptive threshold. Our findings revealed that, when orally administered, ZnO NPs at concentrations ranging from 5-20 mg/kg exerted a dose-dependent analgesic effect in both the hot-plate and the acetic acid-induced writhing tests. Moreover, when ZnO NPs were administered at doses between 2.5-10 mg/kg, there was a notable reduction in pain responses during both the initial and subsequent phases of the formalin test, but no change in PGE 2 production within the mice's hind paw was found. On the other hand, acute lung injury studies revealed that the administration of ZnO NPs orally 90 minutes prior to HCl instillation decreased the neutrophil infiltration into the lungs in a doseresponsive manner. This reduction in pulmonary inflammation was paralleled by a significant decrease in lung edema, as evidenced by the reduced total protein content in the BALF. Additionally, the ZnO NPs appeared to recalibrate the lung's redox equilibrium following HCl exposure, which was determined through measurements of ROS, malondialdehyde, glutathione, and catalase activity. All these results further indicated the potential of biofabricated ZnO NPs for future applications in analgesics and acute lung injury treatments.