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1.
Acta Pharmacol Sin ; 44(9): 1856-1866, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37193755

RESUMO

Psychological stress increases the susceptibility to herpes simplex virus type 1 (HSV-1) infection. There is no effective intervention due to the unknown pathogenesis mechanisms. In this study we explored the molecular mechanisms underlying stress-induced HSV-1 susceptibility and the antiviral effect of a natural compound rosmarinic acid (RA) in vivo and in vitro. Mice were administered RA (11.7, 23.4 mg·kg-1·d-1, i.g.) or acyclovir (ACV, 206 mg·kg-1·d-1, i.g.) for 23 days. The mice were subjected to restraint stress for 7 days followed by intranasal infection with HSV-1 on D7. At the end of RA or ACV treatment, mouse plasma samples and brain tissues were collected for analysis. We showed that both RA and ACV treatment significantly decreased stress-augmented mortality and alleviated eye swelling and neurological symptoms in HSV-1-infected mice. In SH-SY5Y cells and PC12 cells exposed to the stress hormone corticosterone (CORT) plus HSV-1, RA (100 µM) significantly increased the cell viability, and inhibited CORT-induced elevation in the expression of viral proteins and genes. We demonstrated that CORT (50 µM) triggered lipoxygenase 15 (ALOX15)-mediated redox imbalance in the neuronal cells, increasing the level of 4-HNE-conjugated STING, which impaired STING translocation from the endoplasmic reticulum to Golgi; the abnormality of STING-mediated innate immunity led to HSV-1 susceptibility. We revealed that RA was an inhibitor of lipid peroxidation by directly targeting ALOX15, thus RA could rescue stress-weakened neuronal innate immune response, thereby reducing HSV-1 susceptibility in vivo and in vitro. This study illustrates the critical role of lipid peroxidation in stress-induced HSV-1 susceptibility and reveals the potential for developing RA as an effective intervention in anti-HSV-1 therapy.


Assuntos
Herpes Simples , Herpesvirus Humano 1 , Neuroblastoma , Humanos , Animais , Camundongos , Herpesvirus Humano 1/genética , Peroxidação de Lipídeos , Aciclovir/farmacologia , Aciclovir/uso terapêutico , Herpes Simples/tratamento farmacológico
2.
Clin Sci (Lond) ; 135(3): 447-463, 2021 02 12.
Artigo em Inglês | MEDLINE | ID: mdl-33458764

RESUMO

Abnormal vascular smooth muscle cell (VSMC) proliferation is a critical step in the development of atherosclerosis. Serpina3c is a serine protease inhibitor (serpin) that plays a key role in metabolic diseases. The present study aimed to investigate the role of serpina3c in atherosclerosis and regulation of VSMC proliferation and possible mechanisms. Serpina3c is down-regulated during high-fat diet (HFD)-induced atherosclerosis. An Apoe-/-/serpina3c-/--double-knockout mouse model was used to determine the role of serpina3c in atherosclerosis after HFD for 12 weeks. Compared with Apoe-/- mice, the Apoe-/-/serpina3c-/- mice developed more severe atherosclerosis, and the number of VSMCs and macrophages in aortic plaques was significantly increased. The present study revealed serpina3c as a novel thrombin inhibitor that suppressed thrombin activity. In circulating plasma, thrombin activity was high in the Apoe-/-/serpina3c-/- mice, compared with Apoe-/- mice. Immunofluorescence staining showed thrombin and serpina3c colocalization in the liver and aortic cusp. In addition, inhibition of thrombin by dabigatran in serpina3c-/- mice reduced neointima lesion formation due to partial carotid artery ligation. Moreover, an in vitro study confirmed that thrombin activity was also decreased by serpina3c protein, supernatant and cell lysate that overexpressed serpina3c. The results of experiments showed that serpina3c negatively regulated VSMC proliferation in culture. The possible mechanism may involve serpina3c inhibition of ERK1/2 and JNK signaling in thrombin/PAR-1 system-mediated VSMC proliferation. Our results highlight a protective role for serpina3c as a novel thrombin inhibitor in the development of atherosclerosis, with serpina3c conferring protection through the thrombin/PAR-1 system to negatively regulate VSMC proliferation through ERK1/2 and JNK signaling.


Assuntos
Aterosclerose/metabolismo , Serpinas/farmacologia , Trombina/efeitos dos fármacos , Animais , Antitrombinas/farmacologia , Aorta , Apolipoproteínas E/deficiência , Aterosclerose/patologia , Células Cultivadas , Dabigatrana/farmacologia , Dieta Hiperlipídica , Masculino , Camundongos Endogâmicos C57BL , Camundongos Knockout , Neointima , Placa Aterosclerótica/metabolismo , Serpinas/genética , Transdução de Sinais
3.
FASEB J ; 34(8): 10998-11014, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32619083

RESUMO

Chronic stress-evoked depression has been implied to associate with the decline of adult hippocampal neurogenesis. Caffeine has been known to combat stress-evoked depression. Herein, we aim to investigate whether the protective effect of caffeine on depression is related with improving adult hippocampus neurogenesis and explore the mechanisms. Mouse chronic water immersion restraint stress (CWIRS) model, corticosterone (CORT)-established cell stress model, a coculture system containing CORT-treated BV-2 cells and hippocampal neural stem cells (NSCs) were utilized. Results showed that CWIRS caused obvious depressive-like disorders, abnormal 5-HT signaling, and elevated-plasma CORT levels. Notably, microglia activation-evoked brain inflammation and inhibited neurogenesis were also observed in the hippocampus of stressed mice. In comparison, intragastric administration of caffeine (10 and 20 mg/kg, 28 days) significantly reverted CWIRS-induced depressive behaviors, neurogenesis recession and microglia activation in the hippocampus. Further evidences from both in vivo and in vitro mechanistic experiments demonstrated that caffeine treatment significantly suppressed microglia activation via the A2AR/MEK/ERK/NF-κB signaling pathway. The results suggested that CORT-induced microglia activation contributes to stress-mediated neurogenesis recession. The antidepression effect of caffeine was associated with unlocking microglia activation-induced neurogenesis inhibition.


Assuntos
Cafeína/farmacologia , Corticosterona/farmacologia , Hipocampo/efeitos dos fármacos , Microglia/efeitos dos fármacos , Neurogênese/efeitos dos fármacos , Estresse Fisiológico/efeitos dos fármacos , Animais , Antidepressivos/farmacologia , Depressão/tratamento farmacológico , Depressão/metabolismo , Modelos Animais de Doenças , Hipocampo/metabolismo , Masculino , Camundongos , Microglia/metabolismo , Células-Tronco Neurais/efeitos dos fármacos , Células-Tronco Neurais/metabolismo , Serotonina/metabolismo , Transdução de Sinais/efeitos dos fármacos
4.
Ecotoxicol Environ Saf ; 227: 112886, 2021 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-34673406

RESUMO

Atrazine (ATR) is a widely used herbicide that can induce the degeneration of dopaminergic (DAergic) neurons in the substantia nigra, resulting in a Parkinson's disease-like syndrome. Despite the high risk of environmental exposure, few studies have investigated strategies for the prevention of ATR neurotoxicity. Our previous studies demonstrated that ATR can impair mitochondrial function, leading to metabolic failure. Cells maintain mitochondrial quality through selective autophagic elimination, termed mitophagy. Soybean isoflavones (SI) possess multiple beneficial bioactivities, including preservation of mitochondria function, so it was hypothesized that SI can protect neurons against ATR toxicity by promoting mitophagy. Pretreatment of SH-SY5Y neurons with SI prevented ATR-induced metabolic failure and cytotoxicity as assessed by intracellular ATP, Na+-K+-ATPase activity, mitochondrial membrane potential, and cell viability assays. The neuroprotective efficacy of SI was superior to the major individual components genistein, daidzein, and glycitein. Ultrastructural analyses revealed that ATR induced mitochondrial damage, while SI promoted the sequestration of damaged mitochondria into autophagic vesicles. Soybean isoflavones also induced mitophagy as evidenced by upregulated expression of BNIP3/NIX, BEX2, and LC3-II, while co-treatment with the mitophagy inhibitor Mdivi-1 blocked SI-mediated neuroprotection and prevented SI from reversing ATR-induced BEX2 downregulation. Furthermore, BEX2 knockdown inhibited SI-induced activation of the BNIP3/NIX pathway, mitophagy, and neuroprotection. These findings suggest that SI protects against ATR-induced mitochondrial dysfunction and neurotoxicity by activating the BEX2/BNIP3/NIX pathway.


Assuntos
Atrazina , Isoflavonas , Mitofagia , Atrazina/toxicidade , Neurônios Dopaminérgicos , Humanos , Isoflavonas/farmacologia , Proteínas de Membrana , Proteínas do Tecido Nervoso , Proteínas Proto-Oncogênicas , Glycine max/química , Proteínas Supressoras de Tumor
5.
Eur Respir J ; 56(5)2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32527738

RESUMO

INTRODUCTION: Acute lung injury (ALI) is a fatal but undertreated condition with severe neutrophilic inflammation, although little is known about the functions of eosinophils in the pathogenesis of ALI. Our objectives were to investigate the roles and molecular mechanisms of eosinophils in ALI. METHODS: Pulmonary eosinophils were identified by flow cytometry. Mice with abundant or deficient eosinophils were used. Cellularity of eosinophils and neutrophils in bronchoalveolar lavage fluid, inflammatory assessment, and survival rate were determined. Human samples were also used for validating experimental results. RESULTS: Blood eosinophils were increased in surviving patients with acute respiratory distress syndrome (ARDS) independent of corticosteroid usage. There existed homeostatic eosinophils in lung parenchyma in mice and these homeostatic eosinophils, originating from the bone marrow, were predominantly CD101-. More CD101- eosinophils could be recruited earlier than lipopolysaccharide (LPS)-initiated neutrophilic inflammation. Loss of eosinophils augmented LPS-induced pulmonary injury. Homeostatic CD101- eosinophils ameliorated, while allergic CD101+ eosinophils exacerbated, the neutrophilic inflammation induced by LPS. Likewise, CD101 expression in eosinophils from ARDS patients did not differ from healthy subjects. Mechanistically, CD101- eosinophils exhibited higher levels of Alox15 and Protectin D1. Administration of Protectin D1 isomer attenuated the neutrophilic inflammation. CONCLUSIONS: Collectively, our findings identify an uncovered function of native CD101- eosinophils in suppressing neutrophilic lung inflammation and suggest a potential therapeutic target for ALI.


Assuntos
Lesão Pulmonar Aguda , Endotoxinas , Lesão Pulmonar Aguda/induzido quimicamente , Animais , Líquido da Lavagem Broncoalveolar , Eosinófilos , Humanos , Lipopolissacarídeos , Pulmão , Camundongos
6.
Eur Respir J ; 56(3)2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32366484

RESUMO

It is currently not understood whether cigarette smoke exposure facilitates sensitisation to self-antigens and whether ensuing auto-reactive T cells drive chronic obstructive pulmonary disease (COPD)-associated pathologies.To address this question, mice were exposed to cigarette smoke for 2 weeks. Following a 2-week period of rest, mice were challenged intratracheally with elastin for 3 days or 1 month. Rag1-/- , Mmp12-/- , and Il17a-/- mice and neutralising antibodies against active elastin fragments were used for mechanistic investigations. Human GVAPGVGVAPGV/HLA-A*02:01 tetramer was synthesised to assess the presence of elastin-specific T cells in patients with COPD.We observed that 2 weeks of cigarette smoke exposure induced an elastin-specific T cell response that led to neutrophilic airway inflammation and mucus hyperproduction following elastin recall challenge. Repeated elastin challenge for 1 month resulted in airway remodelling, lung function decline and airspace enlargement. Elastin-specific T cell recall responses were dose dependent and memory lasted for over 6 months. Adoptive T cell transfer and studies in T cells deficient Rag1-/- mice conclusively implicated T cells in these processes. Mechanistically, cigarette smoke exposure-induced elastin-specific T cell responses were matrix metalloproteinase (MMP)12-dependent, while the ensuing immune inflammatory processes were interleukin 17A-driven. Anti-elastin antibodies and T cells specific for elastin peptides were increased in patients with COPD.These data demonstrate that MMP12-generated elastin fragments serve as a self-antigen and drive the cigarette smoke-induced autoimmune processes in mice that result in a bronchitis-like phenotype and airspace enlargement. The study provides proof of concept of cigarette smoke-induced autoimmune processes and may serve as a novel mouse model of COPD.


Assuntos
Elastina , Doença Pulmonar Obstrutiva Crônica , Animais , Autoimunidade , Modelos Animais de Doenças , Humanos , Pulmão , Camundongos , Camundongos Endogâmicos C57BL , Fumaça/efeitos adversos , Fumar/efeitos adversos
7.
Chem Biodivers ; 17(1): e1900436, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31705573

RESUMO

A facile method was developed for synthesis of boronic acid-functionalized silica nanocomposites (SiO2 -BA) by 'thiol-ene' click reaction, where silica nanoparticles were synthesized by using tetraethoxysilane (TEOS) and γ-mercaptopropyl trimethoxysilane (γ-MPTS) as precursors. The morphology and structure properties of the resultant SiO2 -BA were characterized by transmission electronic microscopy (TEM), Fourier transform infrared spectroscopy (FT-IR), and Brunner-Emmet-Teller measurements (BET). The adsorption behavior of the SiO2 -BA for glycoproteins was evaluated. Under the optimized conditions, the SiO2 -BA exhibited higher adsorption capacity towards glycoproteins (ovalbumin, OVA, 7.64 µmol/g) than non-glycoproteins (bovine serum albumin, BSA, 0.83 µmol/g). In addition, the practicality of the SiO2 -BA was further assessed by selective enrichment of glycoproteins from egg white samples.


Assuntos
Ácidos Borônicos/química , Glicoproteínas/química , Nanocompostos/química , Dióxido de Silício/química , Adsorção , Clara de Ovo/química , Estrutura Molecular , Tamanho da Partícula , Dióxido de Silício/síntese química , Propriedades de Superfície
8.
J Sci Food Agric ; 100(9): 3598-3607, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32100298

RESUMO

BACKGROUND: Pingwu Fuzhuan brick tea is a type of post-fermented tea manufactured from leaves of the tea plant, Camellia sinensis var. sinensis, the quality of which is influenced by numerous factors, especially microorganisms. Currently, there is little research on the effect of microorganisms on the fermentation and quality characteristics of Pingwu Fuzhuan brick tea. Investigation of the main fungus in this tea and its effect on the fermentation process and tea quality can provide insights into the manufacturing of 'western road' border-selling tea and could lay the foundation for the popularization of Pingwu Fuzhuan brick tea. RESULTS: The main 'golden flower fungus' in Pingwu Fuzhuan brick tea was isolated and identified as Eurotium cristatum (GenBank accession number: MF800948.1; strain PW-1). Compared with natural fermentation, PW-1 inoculated fermentation accelerated biotransformation of phenolic compounds, which provided tea samples with better taste and tea infusion color. The proportions of velvety and sweet-tasting amino acids increased after 16-day fermentation with PW-1. Alcohols were the most abundant volatiles, with 40.13% and 39.43% content in NF16d and IF16d tea samples, respectively. Orthogonal partial least-squares discriminant analysis (OPLS-DA) and hierarchical clustering analysis (HCA) further revealed that naturally fermented and PW-1 fermented teas were significantly different. CONCLUSION: Strain PW-1 plays an important role in the fermentation process of Fuzhuan brick tea. Considering fermentation efficiency and tea quality, fermentation inoculated with E. cristatum PW-1 can be applied in the manufacturing of 'western road' border-selling tea. © 2020 Society of Chemical Industry.


Assuntos
Camellia sinensis/química , Eurotium/metabolismo , Folhas de Planta/microbiologia , Camellia sinensis/microbiologia , Eurotium/classificação , Eurotium/genética , Eurotium/isolamento & purificação , Fermentação , Folhas de Planta/química , Chá/química
9.
Sheng Li Xue Bao ; 72(5): 575-585, 2020 Oct 25.
Artigo em Zh | MEDLINE | ID: mdl-33106828

RESUMO

Ferroptosis is a novel form of regulated cell death which is dependent on iron and reactive oxygen species (ROS) and associated with the accumulation of lipid peroxides. It is obviously different from other cell death types in terms of morphology, biochemistry, genetics, etc. Also, it is related to the production of iron catalyzed lipid peroxides which is triggered by non-enzymatic or enzymatic reactions. Ferroptosis has been proved to be involved in hematological diseases, cardio-cerebrovascular diseases, liver and kidney diseases. This paper will review the definition, mechanism, inducers of ferroptosis, as well as the function of ferroptosis in respiratory system. We expect to present a new concept for respiratory research and suggest potential targets for clinical prevention and treatment of respiratory diseases.


Assuntos
Ferroptose , Transtornos Respiratórios , Morte Celular , Humanos , Ferro , Espécies Reativas de Oxigênio
10.
Acta Pharmacol Sin ; 40(6): 769-780, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30446733

RESUMO

Tissue factor (TF)-dependent coagulation contributes to lung inflammation and the pathogenesis of acute lung injury (ALI). In this study, we explored the roles of targeted endothelial anticoagulation in ALI using two strains of transgenic mice expressing either a membrane-tethered human tissue factor pathway inhibitor (hTFPI) or hirudin fusion protein on CD31+ cells, including vascular endothelial cells (ECs). ALI was induced by intratracheal injection of LPS, and after 24 h the expression of TF and protease-activated receptors (PARs) on EC in lungs were assessed, alongside the extent of inflammation and injury. The expression of TF and PARs on the EC in lungs was upregulated after ALI. In the two strains of transgenic mice, expression of either of hTFPI or hirudin by EC was associated with significant reduction of inflammation, as assessed by the extent of leukocyte infiltration or the levels of proinflammatory cytokines, and promoted survival after LPS-induced ALI. The beneficial outcomes were associated with inhibition of the expression of chemokine CCL2 in lung tissues. The protection observed in the CD31-TFPI-transgenic strain was abolished by injection of an anti-hTFPI antibody, but not by prior engraftment of the transgenic strains with WT bone marrow, confirming that the changes observed were a specific transgenic expression of anticoagulants by EC. These results demonstrate that the inflammation in ALI is TF and thrombin dependent, and that expression of anticoagulants by EC significantly inhibits the development of ALI via repression of leukocyte infiltration, most likely via inhibition of chemokine gradients. These data enhance our understanding of the pathology of ALI and suggest a novel therapeutic strategy for treatment.


Assuntos
Lesão Pulmonar Aguda/metabolismo , Células Endoteliais/metabolismo , Hirudinas/metabolismo , Inflamação/metabolismo , Lipoproteínas/metabolismo , Lesão Pulmonar Aguda/induzido quimicamente , Animais , Coagulação Sanguínea/fisiologia , Quimiocinas/metabolismo , Quimiotaxia de Leucócito/fisiologia , Hirudinas/genética , Humanos , Inflamação/induzido quimicamente , Sanguessugas/química , Lipopolissacarídeos , Lipoproteínas/genética , Pulmão/patologia , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Molécula-1 de Adesão Celular Endotelial a Plaquetas/genética , Molécula-1 de Adesão Celular Endotelial a Plaquetas/metabolismo , Pseudomonas aeruginosa/química , Receptores Ativados por Proteinase/metabolismo , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Trombina/metabolismo , Tromboplastina/metabolismo
11.
Am J Pathol ; 187(2): 280-291, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27912076

RESUMO

Mucus hypersecretion is an important pathologic feature of chronic obstructive pulmonary disease. Activating transcription factor 3 (ATF3) is an adaptive-response gene that participates in various cellular processes. However, little is known about its role in cigarette smoke (CS)-induced mucus hyperproduction. This study aimed to investigate the role and molecular mechanisms of ATF3 in CS-induced Mucin 5AC (MUC5AC) expression. ATF3 was elevated in lung tissues of mice exposed to CS for 12 weeks. Treatment with CS extract significantly induced ATF3 expression and MUC5AC production in human bronchial epithelial cells, NCI-H292, and mouse tracheal epithelial cells. Interference of ATF3 significantly attenuated CS-induced MUC5AC expression in NCI-H292 and human bronchial epithelial cells. Mouse tracheal epithelial cells isolated from Atf3-/- mice also exhibited less MUC5AC production in response to CS extract treatment. In vivo, the Atf3-/- mice also displayed a significantly reduced mucus production relative to wild-type controls in response to chronic CS exposure. Furthermore, a chromatin immunoprecipitation assay revealed increased ATF3 binding to the MUC5AC promoter after CS treatment, and this transcriptional binding was significantly inhibited by knockdown of JUN, a subunit of activator protein-1. These results demonstrate that ATF3 may be involved in activator protein-1 signaling and transcriptional promotion of CS-induced MUC5AC expression in airway epithelial cells.


Assuntos
Fator 3 Ativador da Transcrição/metabolismo , Mucina-5AC/biossíntese , Mucosa Respiratória/patologia , Fumar/efeitos adversos , Fator de Transcrição AP-1/metabolismo , Animais , Western Blotting , Imunoprecipitação da Cromatina , Modelos Animais de Doenças , Humanos , Imuno-Histoquímica , Camundongos , Camundongos Knockout , Reação em Cadeia da Polimerase , Doença Pulmonar Obstrutiva Crônica/metabolismo , Mucosa Respiratória/metabolismo
12.
Bioconjug Chem ; 29(8): 2606-2618, 2018 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-29947505

RESUMO

Here, polyamidoamine grafted halloysite nanotubes (PAMAM- g-HNTs) were synthesized for loading of siRNA in order to intracellular delivery of siRNA and treat of breast cancer via gene therapy. The successful grafting of PAMAM on HNTs was confirmed by various analytical methods. The size, zeta potential, and grafting ratio of PAMAM- g-HNTs is ∼206.2 nm, +19.8 mV, and 3.04%, respectively. PAMAM- g-HNTs showed good cytocompatibility toward HUVECs (84.7%) and MCF-7 cells (82.3%) even at high concentration of 100 µg/mL. PAMAM- g-HNTs/siRNA exhibited enhanced cellular uptake efficiency of 94.3% compared with Lipofectamine 2000 (Lipo2000)/siRNA (83.6%). PAMAM- g-HNTs/small interfering RNA-vascular endothelial growth factor (siVEGF) led to 78.0% knockdown of cellular VEGF mRNA and induced 33.6% apoptosis in the MCF-7 cells, which is also much higher than that of Lipo2000/siVEGF. In vivo anti-cancer results demonstrated that PAMAM- g-HNTs/siVEGF treated 4T1-bearing mice showed enhanced anti-cancer efficacy than Lipo2000/siVEGF group. Also, the nanocarrier system showed negligible toxic effects toward the major organs of mice. In vivo fluorescence imaging studies showed that there is a slight decrease in the fluorescence signal of PAMAM- g-HNTs/cy5-siVEGF after 72 h post-injection. Therefore, PAMAM- g-HNTs show promising application as novel nanovectors for siRNA delivery and gene therapy of cancer.


Assuntos
Dendrímeros/química , Nanotubos/química , RNA Interferente Pequeno/administração & dosagem , Animais , Apoptose , Endossomos/metabolismo , Feminino , Inativação Gênica , Terapia Genética , Xenoenxertos , Células Endoteliais da Veia Umbilical Humana , Humanos , Lipídeos/química , Lisossomos/metabolismo , Células MCF-7 , Camundongos , Camundongos Endogâmicos BALB C , Poliaminas/química , Fator A de Crescimento do Endotélio Vascular/genética
13.
Biosci Biotechnol Biochem ; 82(1): 135-138, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29235425

RESUMO

The C-3-OH, C-4 carbonyl oxygen and hydrogenation of C2=C3 bond on the C-ring of 2R,3R-dihydromyricetin (DMY) proved to be not necessary for the antibacterial activity against Staphylococcus aureus. DMY significantly decreased the intracellular ATP of S. aureus cells but had few effects on pHin, proline oxidation, succinate dehydrogenase activity or malate dehydrogenase activity.


Assuntos
Antibacterianos/química , Flavonóis/química , Staphylococcus aureus/efeitos dos fármacos , Antibacterianos/farmacologia , Flavonóis/farmacologia , Malato Desidrogenase/metabolismo , Oxirredução , Prolina/química , Succinato Desidrogenase/metabolismo
14.
Foodborne Pathog Dis ; 15(8): 475-480, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29847738

RESUMO

The adherence and biofilm formation of Staphylococcus aureus on food contact surfaces are a major concern for the food industry. Development of antibiofilm agents from polyphenols has drawn much attention due to their potent activity. The present study explored the antibacterial and antibiofilm activities of 2R,3R-dihydromyricetin (DMY) against S. aureus ATCC 29213. It was found that DMY exerted excellent antibacterial and bactericidal properties against S. aureus with minimum inhibitory concentration and minimum bactericidal concentration values of 0.125 and 0.25 mg/mL, respectively. Crystal violet staining and 2,3-bis (2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxanilide sodium salt reduction assay demonstrated that DMY significantly reduced the biofilm biomass of S. aureus and decreased the metabolic activity of biofilm cells. Micrographs of light microscope and scanning electron microscope confirmed that DMY inhibited the biofilm formation and caused a disintegration of the complex biofilm architecture. Moreover, DMY was highly efficient in reducing the number of sessile S. aureus cells adhered to stainless steel. These results suggested that DMY could have potential application to control S. aureus contamination in a food processing environment.


Assuntos
Antibacterianos/farmacologia , Biofilmes/efeitos dos fármacos , Flavonóis/farmacologia , Staphylococcus aureus/efeitos dos fármacos , Contaminação de Alimentos/prevenção & controle , Testes de Sensibilidade Microbiana , Microscopia Eletrônica de Varredura , Aço Inoxidável
15.
Cell Physiol Biochem ; 43(5): 1866-1879, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29049987

RESUMO

BACKGROUND/AIMS: Atrazine (ATR) is a broad-spectrum herbicide in wide use around the world. However, ATR is neurotoxic and can cause cell death in dopaminergic neurons, leading to neurodegenerative disorders. Autophagy is the basic cellular catabolic process involving the degradation of proteins and damaged organelles. Studies have shown that certain plant compounds can induce autophagy and prevent neuronal cell death. This prompted us to investigate plant compounds that might reduce the neurotoxic effects of ATR. METHODS: By CCK-8 and flow cytometry, we tested the ability of five candidate compounds-isoflavones, resveratrol, quercetin, curcumin, and green tea polyphenols-to protect cells from ATR. Changes in the expression of tyrosine hydroxylase (TH) and brain-expressed X-linked 2 (BEX2), autophagy-related proteins and key factors in mTOR signaling, were detected by Western blotting. RESULTS: Isoflavones had the strongest activity against ATR-induced neuronal apoptosis. ATR reduced the expression of TH and BEX2, whereas isoflavones increased TH and BEX2 expression. In addition, ATR inhibited autophagy, whereas isoflavones induced autophagy through the accumulation of LC3-II and decreased expression of p62; this effect was abolished by 3-methyladenine (3-MA). Furthermore, BEX2 siRNA abolished isoflavone-mediated autophagy and neuroprotection in vitro. CONCLUSION: Isoflavones activate BEX2-dependent autophagy, protecting against ATR-induced neuronal apoptosis.


Assuntos
Autofagia/efeitos dos fármacos , Isoflavonas/farmacologia , Proteínas do Tecido Nervoso/metabolismo , Apoptose/efeitos dos fármacos , Atrazina/farmacologia , Western Blotting , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Curcumina/farmacologia , Citometria de Fluxo , Humanos , Polifenóis/farmacologia , Quercetina/farmacologia , Reação em Cadeia da Polimerase em Tempo Real , Resveratrol , Sincalida/metabolismo , Estilbenos/farmacologia , Serina-Treonina Quinases TOR/metabolismo , Tirosina 3-Mono-Oxigenase/metabolismo
16.
Biochem Biophys Res Commun ; 490(2): 147-154, 2017 08 19.
Artigo em Inglês | MEDLINE | ID: mdl-28602698

RESUMO

Early growth response factor 1 (Egr-1) is a zinc finger transcription factor which responses rapidly to a variety of extracellular stimuli. Previous studies have suggested that Egr-1 exerts pathological functions in chronic obstructive pulmonary disease (COPD) by regulation of cigarette smoking-induced autophagy, cell death, and inflammation. However, little is known about the role of Egr-1 in regulation of mucus production in airway epithelium. In this study, we observed that cigarette smoke extract (CSE) induced a successive expression of Egr-1 and MUC5AC in human bronchial epithelial (HBE) cells. Knockdown of Egr-1 markedly attenuated CSE-induced MUC5AC production, and chromatin immunoprecipitation revealed that Egr-1 transcriptionally bound to MUC5AC promoter upon CSE stimulation. Concurrently, CSE increased the expression of c-Jun and c-Fos, two subunits of activator protein 1 (AP-1) which also critically regulates CSE-induced MUC5AC in HBE cells. CSE also induced a physical interaction of Egr-1 and AP-1, and knockdown of Egr-1 significantly decreased CSE-induced expression of c-Fos and c-Jun. Furthermore, knockdown of c-Fos remarkably attenuated the CSE-induced Egr-1 binding to MUC5AC promoter. These data taken together demonstrate that Egr-1 is essential for CSE-induced MUC5AC production in HBE cells likely through interaction with and modulation of AP-1, and re-emphasize targeting Egr-1 as a novel therapeutic strategy for COPD.


Assuntos
Brônquios/metabolismo , Proteína 1 de Resposta de Crescimento Precoce/metabolismo , Células Epiteliais/metabolismo , Mucina-5AC/genética , Fumar , Brônquios/patologia , Células Cultivadas , Proteína 1 de Resposta de Crescimento Precoce/genética , Proteína 1 de Resposta de Crescimento Precoce/isolamento & purificação , Células Epiteliais/patologia , Humanos , Mucina-5AC/metabolismo
17.
Birth Defects Res B Dev Reprod Toxicol ; 104(5): 184-9, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26331294

RESUMO

Atrazine (ATR, 2-chloro-4-ethylamino-6-isopropylamino-s-triazine) is used worldwide as a herbicide, and its presence in the environment has resulted in documented human exposure. A lack of strong evidence for genetic heritability of idiopathic Parkinson's disease has focused attention on environmental toxicants in the disease etiology, particularly agrichemicals. Parkinson's disease is associated with advanced age and is characterized by the degeneration of dopaminergic neurons, but it is unclear whether specific neuronal damage could result from insults during development. The juvenile period is particularly vulnerable to environmental agent, therefore, we evaluated the effects of a 28-day exposure to ATR on the dopaminergic system in pubertal rats. Sprague-Dawley rats were treated orally with ATR at 50, 100, and 200 mg/kg bw, daily from postnatal days 27 to 54. In this study, we examined the hypothesis that pubertal exposure to ATR would disrupt the development of the nigrostriatal dopamine (DA) system. The content of DA and levodopa (L-DA) were examined in striatum samples by HPLC-FL, and the mRNA and protein expression of tyrosine hydroxylase, orphan nuclear hormone receptor (Nurr1), Nurr1 interacting protein (NuIP), and cyclin-dependent kinase inhibitors of the Cip̲Kip family (p57kip2) were examined in samples of the nigrostriatum by use of fluorescence Real-Time quantitative polymerase chain reaction (PCR). Exposure of juvenile rats to the high dose of ATR led to reduced levels of DA and L-DA, genes expression of NuIP, Nurr1, and p57kip2 in animals.


Assuntos
Atrazina/toxicidade , Dopamina/metabolismo , Exposição Ambiental , Maturidade Sexual/efeitos dos fármacos , Animais , Corpo Estriado/efeitos dos fármacos , Corpo Estriado/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Levodopa/metabolismo , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos Sprague-Dawley , Reação em Cadeia da Polimerase em Tempo Real , Aprendizagem Espacial/efeitos dos fármacos , Natação
18.
Int J Mol Sci ; 16(6): 13490-506, 2015 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-26075868

RESUMO

Atrazine (2-chloro-4-ethytlamino-6-isopropylamine-1,3,5-triazine; ATR) is widely used as a broad-spectrum herbicide. Animal studies have demonstrated that ATR exposure can cause cell death in dopaminergic neurons. The molecular mechanisms underlying ATR-induced neuronal cell death, however, are unknown. In this study, we investigated the autophagy and apoptosis induced by ATR in dopaminergic neurons in vivo. Wistar rats were administered with ATR at doses of 10, 50 and 100 mg/kg body weight by oral gavage for three months. In terms of histopathology, the expression of autophagy- and apoptosis-related genes as well as proteins related to the Beclin-1/B-cell lymphoma 2 (Bcl-2) autophagy and apoptosis pathways were examined in the rat nigrostriatal dopaminergic system. We observed degenerative micromorphology indicative of neuronal apoptosis and mitochondrial autophagy by electron microscopy in ATR-exposed rat striatum. The rat ventral mesencephalon in the ATR-exposed groups also showed increased expression of Beclin-1, LC3-II, Bax and Caspase-9, and decreased expression of tyrosine hydroxylase (TH), Bcl-xl and Bcl-2. These findings indicate that ATR may induce autophagy- and apoptosis-related changes in doparminergic neurons. Furthermore, this induction may be regulated by the Beclin-1 and Bcl-2 autophagy and apoptosis pathways, and this may help to better understand the mechanism underlying the neurotoxicity of ATR.


Assuntos
Apoptose , Atrazina/toxicidade , Autofagia , Neurônios Dopaminérgicos/efeitos dos fármacos , Herbicidas/toxicidade , Animais , Proteínas Reguladoras de Apoptose/metabolismo , Atrazina/efeitos adversos , Proteína Beclina-1 , Caspase 9/metabolismo , Neurônios Dopaminérgicos/metabolismo , Herbicidas/efeitos adversos , Masculino , Mesencéfalo/citologia , Mesencéfalo/efeitos dos fármacos , Mesencéfalo/metabolismo , Mesencéfalo/ultraestrutura , Proteínas Associadas aos Microtúbulos/metabolismo , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Ratos , Ratos Wistar , Proteína X Associada a bcl-2/metabolismo
19.
J Sci Food Agric ; 95(6): 1236-42, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25043720

RESUMO

BACKGROUND: Heavy tea consumption is suggested to be unsuitable for hypertensive people. However, the bioactive substances in different varieties of tea leaves are very different. This study compares the effects of three Chinese teas - C. sinensis, C. ptilophylla and C. assamica var. kucha - on blood pressure (BP) and heart rate in spontaneously hypertensive rats (SHRs). RESULTS: Intragastric administration of C. sinensis extract led to an acute increase in systolic blood pressure (SBP), diastolic blood pressure (DBP) and heart rate in SHRs. However, C. ptilophylla and C. assamica var. kucha exerted no obvious influences on SBP, DBP or heart rate. Similar to the extract of C. sinensis, intragastric administration of caffeine also led to an acute increase in BP and heart rate in SHRs. In contrast, theobromine and theacrine - purine alkaloids predominantly contained in C. ptilophylla and C. assamica var. kucha, respectively - had no pressor effects. The effect of caffeine on BP was related to the regulation of plasma epinephrine and norepinephrine levels in SHRs. CONCLUSION: The different effects of C. sinensis, C. ptilophylla and C. assamica var. kucha on BP might be explained, at least partially, by the differences in the varieties and contents of purine alkaloids.


Assuntos
Pressão Sanguínea/efeitos dos fármacos , Camellia sinensis/química , Hipertensão , Extratos Vegetais/farmacologia , Chá/química , Xantinas/farmacologia , Animais , Cafeína/farmacologia , Camellia sinensis/classificação , Epinefrina/sangue , Hipertensão/sangue , Hipertensão/fisiopatologia , Masculino , Norepinefrina/sangue , Ratos Endogâmicos SHR , Ratos Wistar , Especificidade da Espécie , Chá/classificação , Teobromina/farmacologia , Ácido Úrico/análogos & derivados , Ácido Úrico/farmacologia
20.
Arch Virol ; 159(12): 3457-61, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25168045

RESUMO

This study reports the complete genome sequence of an infectious bronchitis virus (CK/CH/SD/121220, KJ128295) isolated in 2012 from Shandong Province in northern China. The genome is 27,666 nt long, comprising six genes and 5' and 3' untranslated regions. The full-length genome of the CK/CH/SD/121220 isolate had the highest nucleotide sequence identity (96.7 %) to the YX10 strain. Sites of recombination were identified in the genes 1ab, S, 5a, 5b and N, with their putative parental strains belonging to the QX- and YN-type subgroups, which are already circulating in China. Our findings suggest an important role played by recombination in IBV evolution.


Assuntos
Genoma Viral , Vírus da Bronquite Infecciosa/genética , RNA Viral/genética , Análise de Sequência de DNA , Regiões 3' não Traduzidas , Regiões 5' não Traduzidas , China , Análise por Conglomerados , Genes Virais , Vírus da Bronquite Infecciosa/isolamento & purificação , Dados de Sequência Molecular , Filogenia , Recombinação Genética , Homologia de Sequência do Ácido Nucleico
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