RESUMO
BACKGROUND: Community-acquired pneumonia (CAP) is a major public health challenge worldwide. However, the aetiological and disease severity-related pathogens associated with CAP in adults in China are not well established based on the detection of both viral and bacterial agents. METHODS: A multicentre, prospective study was conducted involving 10 hospitals located in nine geographical regions in China from 2014 to 2019. Sputum or bronchoalveolar lavage fluid (BALF) samples were collected from each recruited CAP patient. Multiplex real-time PCR and bacteria culture methods were used to detect respiratory pathogens. The association between detected pathogens and CAP severity was evaluated. RESULTS: Among the 3,403 recruited eligible patients, 462 (13.58%) had severe CAP, and the in-hospital mortality rate was 1.94% (66/3,403). At least one pathogen was detected in 2,054 (60.36%) patients, with two or more pathogens were co-detected in 725 patients. The ten major pathogens detected were Mycoplasma pneumoniae (11.05%), Haemophilus influenzae (10.67%), Klebsiella pneumoniae (10.43%), influenza A virus (9.49%), human rhinovirus (9.02%), Streptococcus pneumoniae (7.43%), Staphylococcus aureus (4.50%), adenovirus (2.94%), respiratory syncytial viruses (2.35%), and Legionella pneumophila (1.03%), which accounted for 76.06-92.52% of all positive detection results across sampling sites. Klebsiella pneumoniae (p < 0.001) and influenza viruses (p = 0.005) were more frequently detected in older patients, whereas Mycoplasma pneumoniae was more frequently detected in younger patients (p < 0.001). Infections with Klebsiella pneumoniae, Staphylococcus aureus, influenza viruses and respiratory syncytial viruses were risk factors for severe CAP. CONCLUSIONS: The major respiratory pathogens causing CAP in adults in China were different from those in USA and European countries, which were consistent across different geographical regions over study years. Given the detection rate of pathogens and their association with severe CAP, we propose to include the ten major pathogens as priorities for clinical pathogen screening in China.
Assuntos
Infecções Comunitárias Adquiridas , Legionella pneumophila , Pneumonia Bacteriana , Pneumonia , Humanos , Adulto , Idoso , Pneumonia Bacteriana/diagnóstico , Pneumonia Bacteriana/epidemiologia , Pneumonia Bacteriana/complicações , Estudos Prospectivos , Pneumonia/diagnóstico , Pneumonia/epidemiologia , Pneumonia/etiologia , Streptococcus pneumoniae , Mycoplasma pneumoniae , Vírus Sinciciais Respiratórios , Klebsiella pneumoniae , Infecções Comunitárias Adquiridas/diagnóstico , Infecções Comunitárias Adquiridas/epidemiologia , Infecções Comunitárias Adquiridas/etiologiaRESUMO
As a major virulence factor of Listeria monocytogenes (L. monocytogenes), listeriolysin O (LLO) can assist in the immune escape of L. monocytogenes, which is critical for the pathogen to evade host immune recognition, leading to various infectious diseases. Cinnamon twig (CT), as a traditional medicine, has been widely used in clinics for multiple functions and it has exhibited excellent safety, efficacy and stability. There are few reports on the effects of the extracts of traditional medicine on bacterial virulence factors. CT has not been reported to be effective in the treatment of L. monocytogenes infection. Therefore, this study aims to explore the preventive effect of CT against L. monocytogenes infection in vivo and in vitro by targeting LLO. Firstly, a hemolysis assay and a cell viability determination are used to detect the effect of CT extract on the inhibition of the cytolytic activity of LLO. The potential mechanism through which CT extract inhibits LLO activity is predicted through network pharmacology, molecular docking assay, real-time polymerase chain reaction (RT-PCR), Western blotting and circular dichroism (CD) analysis. The experimental therapeutic effect of CT extract is examined in a mouse model infected with L. monocytogenes. Then, the ingredients are identified through a high-performance liquid chromatography (HPLC) and thin layer chromatography (TLC) analysis. Here we find that CT extract, containing mainly cinnamic acid, cinnamaldehyde, ß-sitosterol, taxifolin, catechin and epicatechin, shows a potential inhibition of LLO-mediated hemolysis without any antimicrobial activity. The results of the mechanism research show that CT extract treatment can simultaneously inhibit LLO expression and oligomerization. Furthermore, the addition of CT extract led to a remarkable alleviation of LLO-induced cytotoxicity. After treatment with CT extract, the mortality, bacterial load, pathological damage and inflammatory responses of infected mice are significantly reduced when compared with the untreated group. This study suggests that CT extract can be a novel and multicomponent inhibitor of LLO with multiple strategies against L. monocytogenes infection, which could be further developed into a novel treatment for infections caused by L. monocytogenes.
Assuntos
Listeria monocytogenes , Listeriose , Animais , Camundongos , Cinnamomum zeylanicum , Simulação de Acoplamento Molecular , Hemólise , Listeriose/tratamento farmacológico , Listeriose/microbiologia , Proteínas Hemolisinas , Fatores de Virulência/metabolismoRESUMO
The efficacy of colistin, the last option against multidrug-resistant (MDR) Gram-negative bacteria, is severely threatened by the prevalence of plasmid- or chromosome-mediated colistin resistance genes. Herein, naringenin has dramatically restored colistin sensitivity against colistin-resistant Klebsiella pneumoniae infection without affecting bacterial viability, inducing resistance and causing obvious cell toxicity. Mechanism analysis reveals that naringenin potentiates colistin activity by multiple strategies including inhibition of mobilized colistin resistance gene activity, repression of two-component system regulation, and acceleration of reactive oxygen species-mediated oxidative damage. A lung-targeted delivery system of naringenin microspheres has been designed to facilitate naringenin bioavailability, accompanied by an effective potentiation of colistin for Klebsiella pneumoniae infection. Consequently, a new recognition of naringenin microspheres has been elucidated to restore colistin efficacy against colistin-resistant Gram-negative pathogens, which may be an effective strategy of developing potential candidates for MDR Gram-negative bacteria infection.
Assuntos
Antibacterianos , Colistina , Colistina/farmacologia , Antibacterianos/farmacologia , Klebsiella pneumoniae/genética , Microesferas , Testes de Sensibilidade MicrobianaRESUMO
Following the publication of the above article, the authors have realized that an error was made in the Acknowledgements section in this paper; this research was not, in fact, supported by a grant from the National Natural Science Foundation of Jilin (Project no. 83657488), as had been stated. The authors regret their oversight in providing this incorrect information in the Acknowledgements section of their paper. They thank the Editor of Molecular Medicine Reports for allowing them the opportunity to publish this corrigendum, and apologize to the readership of the Journal for any inconvenience caused. [the original article was published in Molecular Medicine Reports 9: 763-767, 2014; DOI: 10.3892/mmr.2013.1850].
RESUMO
The irrational use of broad-spectrum antibiotics has led to increasing resistance of bacteria to antibiotics, and the emergence of the plasmid-mediated colistin resistance gene mcr-1 has led to the dilemma of infections with no available cure. Here, we have found a potential MCR-1 inhibitor for use against infections caused by MCR-1 positive resistant bacteria. A checkerboard MIC (minimum inhibitory concentration) assay, growth curve assay, kill curve assay, cytotoxicity assay, molecular dynamics simulation analysis, Western blot assay and mouse pneumonia model in vivo protection rate assay were used to evaluate the synergy effect between genistein and polymyxins. The results showed that genistein could restore the bactericidal activity against MCR-1-positive strains for which there was no antibacterial activity, and reduce the bacterial load to some extent. Genistein does not inhibit the expression of MCR-1, but inhibits the binding of MCR-1 to its substrate by binding to the amino acids of the active region of MCR-1, thereby inhibiting the biological activity of MCR-1. The in vivo results also showed that the protection rate of mice treated with the combination therapy of genistein and polymyxins increased by 20% compared to that of mice treated with polymyxins alone. Our results confirm that genistein is an inhibitor of MCR-1 and promote its potential use in combination with polymyxins to treat severe infections caused by MCR-1 positive Enterobacteriaceae.
Assuntos
Farmacorresistência Bacteriana Múltipla , Polimixinas , Animais , Antibacterianos/farmacologia , Colistina/farmacologia , Farmacorresistência Bacteriana , Camundongos , Testes de Sensibilidade Microbiana , Plasmídeos , Polimixinas/farmacologiaRESUMO
Gas gangrene, caused mainly by the anaerobic bacterium Clostridium perfringens (C. perfringens), causes death within 48 h of onset. Limited therapeutic strategies are available, and it is associated with extremely high mortality. Both C. perfringens alpha toxin (CPA) and perfringolysin O (PFO) are important virulence factors in the development of gas gangrene, suggesting that they are therapeutic targets. Here, we found that verbascoside, a phenylpropanoid glycoside widely distributed in Chinese herbal medicines, could effectively inhibit the biological activity of both CPA and PFO in hemolytic assays. The oligomerization of PFO was remarkably inhibited by verbascoside. Although no antibacterial activity was observed, verbascoside treatment protected Caco-2 cells from the damage caused by CPA and PFO. Additionally, infected mice treated with verbascoside showed significantly alleviated damage, reduced bacterial burden, and decreased mortality. In summary, verbascoside has an effective therapeutic effect against C. perfringens virulence both in vitro and in vivo by simultaneously targeting CPA and PFO. Our results provide a promising strategy and a potential lead compound for C. perfringens infections, especially gas gangrene.
RESUMO
BACKGROUND: Listeria monocytogenes (L. monocytogenes) is a global opportunistic intracellular pathogen that can cause many infections, including meningitis and abortion in humans and animals; thus, L. monocytogenes poses a great threat to public safety and the development of the aquaculture industry. The isolation rate of Listeria monocytogenes in fishery products has always been high. And the pore-forming toxin listeriolysin O (LLO) is one of the most important virulence factors of L. monocytogenes. LLO can promote cytosolic bacterial proliferation and help the pathogen evade attacks from the host immune system. In addition, L. monocytogenes infection can trigger a series of severe inflammatory reactions. RESULTS: Here, we further confirmed that morin lacking anti-Listeria activity could inhibit LLO oligomerization. We also found that morin can effectively alleviate the inflammation induced by Listeria in vivo and in vitro and exerted an obvious protective effect on infected cells and mice. CONCLUSIONS: Morin does not possess anti-Listeria activity, neither does it interfere with secretion of LLO. However, morin inhibits oligomerisation of LLO and morin does reduce the inflammation caused during Listeria infection.
Assuntos
Toxinas Bacterianas/química , Flavonoides/administração & dosagem , Proteínas de Choque Térmico/química , Proteínas Hemolisinas/química , Listeria monocytogenes/patogenicidade , Listeriose/tratamento farmacológico , Animais , Linhagem Celular , Modelos Animais de Doenças , Flavonoides/farmacologia , Regulação Bacteriana da Expressão Gênica/efeitos dos fármacos , Proteínas de Choque Térmico/efeitos dos fármacos , Proteínas Hemolisinas/efeitos dos fármacos , Humanos , Listeria monocytogenes/efeitos dos fármacos , Listeria monocytogenes/enzimologia , Listeria monocytogenes/crescimento & desenvolvimento , Camundongos , Multimerização Proteica/efeitos dos fármacos , Virulência/efeitos dos fármacosRESUMO
ß-Lactamase-positive Staphylococcus aureus is one of the most prevalent multidrug-resistant pathogens worldwide and is associated with increasing threats to clinical therapeutics and public health. Here, we showed that isoalantolactone (IAL), in combination with penicillin G, exhibited significant synergism against 21 ß-lactamase-positive S. aureus strains (including methicillin resistant S. aureus). An enzyme inhibition assay, a checkerboard minimum inhibitory concentration (MIC) assay, a growth curve assay, a time-killing assay, a RT-PCR assay and Circular Dichroism (CD) spectroscopy were performed on different ß-lactamases or ß-lactamase-positive S. aureus strains, in vitro, to confirm the mechanism of inhibition of ß-lactamase and the synergistic effects of the combination of penicillin G and IAL. All the fractional inhibitory concentration (FIC) indices of penicillin G, in combination with IAL, against ß-lactamase-positive S. aureus, were less than 0.5, and ranged from 0.10 ± 0.02 to 0.38 ± 0.17. The survival rate of S. aureus-infected mice increased significantly from 35.29% to 88.24% within 144 h following multiple compound therapy approaches. Unlike sulbactam, IAL inactivated ß-lactamase during protein translation, and the therapeutic effect of combination therapy with IAL and penicillin G was equivalent to that of sulbactam with penicillin G. Collectively, our results indicated that IAL is a promising and leading drug that can be used to restore the antibacterial effect of ß-lactam antibiotics such as penicillin G and to address the inevitable infection caused by ßlactamase-positive S. aureus.
RESUMO
BACKGROUND: Recent studies have shown 6'-O-galloylpaeoniflorin (GPF), a nature product extracted from the roots of paeoniflorin exerts anti-oxidant and anti-inflammatory activities. However, the effects of GPF on the proliferation and invasion in non-small cell lung cancer (NSCLC) cells have not been clarified. METHODS: MTT assay was performed to determine the cytotoxicity of GPF treatment on NSCLC cells. Colony formation assay, cell scratch test and transwell assay were performed to determine the proliferation and invasion of NSCLC cells in vitro, respectively. An A549 cell xenograft mouse model was performed to confirm the growth of NSCLC cells in vivo. Western blotting was used to measure the levels of activating transcription factor 2 (ATF2), AMP-activated protein kinase (AMPK) and phosph-AMPK (p-AMPK). Luciferase assay was used to validate the binding of miR-299-5p on the 3' untranslated region (UTR) of ATF2. RESULTS: Administration of GPF (50 or 100 µM) was significantly cytotoxic to A549 cells and H1299 cells, as well as inhibited the clonality, invasion and metastasis of NSCLC cells in vitro. GPF treatment also inhibited the tumor growth of NSCLC cell mouse xenografts in vivo. Exotic expression of miR-299-5p significantly inhibited the growth of NSCLC cells in vitro and in vivo. Downregulation of miR-299-5p expression attenuated the inhibition of the proliferation and metastasis of non-small cell lung cancer cells by GPF treatment. miR-299-5p significantly decreased ATF2 mRNA and protein levels in A549 cells (p < 0.05). Overexpression of ATF2 blocked the inhibitory effect of miR-299-5p on the proliferation and invasiveness of A549 cells. CONCLUSIONS: GPF regulates miR-299-5p/ATF2 axis in A549 cells via the AMPK signalling pathway, thereby inhibiting the proliferation and metastasis of non-small cell lung cancer cells.
Assuntos
Fator 2 Ativador da Transcrição/metabolismo , Compostos Bicíclicos Heterocíclicos com Pontes/farmacologia , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Glucosídeos/farmacologia , Neoplasias Pulmonares/metabolismo , Sistema de Sinalização das MAP Quinases/fisiologia , MicroRNAs/metabolismo , Monoterpenos/farmacologia , Células A549 , Fator 2 Ativador da Transcrição/antagonistas & inibidores , Animais , Compostos Bicíclicos Heterocíclicos com Pontes/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/patologia , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/fisiologia , Relação Dose-Resposta a Droga , Feminino , Glucosídeos/uso terapêutico , Humanos , Neoplasias Pulmonares/patologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , MicroRNAs/antagonistas & inibidores , Monoterpenos/uso terapêutico , Ensaios Antitumorais Modelo de Xenoenxerto/métodosRESUMO
Oncol Rep 31: [Related article:] 12711276, 2014; DOI: 10.3892/or.2014.2991. The authors wish to retract their article entitled 'Down-regulation of NOB1 suppresses the proliferation and tumor growth of nonsmall cell lung cancer in vitro and in vivo', published in Oncology Reports 31: 12711276, 2014. The authors have identified that the results shown in Fig. 4A did not display a significant level of difference comparing among the groups, which undermines the conclusions stated in the article. In addition, the 'Acknowledgements' section featured an error in terms of the quoted project number. For these reasons, the authors have decided to withdraw this paper from the Journal. All the named authors agree to this retraction. and regret any inconvenience to the readers and to the Editor of Oncology Reports that this retraction will cause.
RESUMO
Salmonella enterica serovar Typhimurium (S. Typhimurium) is an important zoonotic pathogen in public health and food safety. The type III secretion system (T3SS) encoded by Salmonella pathogenicity island (SPI) is a sophisticated molecular machine that facilitates active invasion, intracellular replication, and host inflammation. Due to increasing antibiotic resistance, new therapeutic strategies that target the Salmonella T3SS have received considerable attention. In this study, paeonol was identified as an inhibitor of the S. Typhimurium T3SS. Paeonol significantly blocked the translocation of SipA into host cells and suppressed the expression of effector proteins without affecting bacterial growth in the effective concentration range. Additionally, S. Typhimurium-mediated cell injury and invasion levels were significantly reduced after treatment with paeonol, without cytotoxicity. Most importantly, the comprehensive protective effect of paeonol was confirmed in an S. Typhimurium mouse infection model. Preliminary mechanistic studies suggest that paeonol inhibits the expression of effector proteins by reducing the transcription level of the SPI-1 regulatory pathway gene hilA. This work provides proof that paeonol could be used as a potential drug to treat infections caused by Salmonella.
Assuntos
Acetofenonas/farmacologia , Paeonia/química , Infecções por Salmonella/tratamento farmacológico , Salmonella typhimurium/efeitos dos fármacos , Sistemas de Secreção Tipo III/antagonistas & inibidores , Animais , Carga Bacteriana , Proteínas de Bactérias/antagonistas & inibidores , Translocação Bacteriana/efeitos dos fármacos , Citocinas/imunologia , Feminino , Camundongos , Camundongos Endogâmicos BALB C , Extratos Vegetais/farmacologia , Transativadores/antagonistas & inibidores , Sistemas de Secreção Tipo III/efeitos dos fármacosRESUMO
Streptococcus suis (S. suis) is one of the most common swine pathogens in the swine industry and leads to great harm to the normal progress of the swine industry. S. suis can also infect humans and cause a variety of fatal diseases, such as meningitis and streptococcal toxic shock syndrome, that pose a major threat to the safety of life and health of both humans and animals. In this paper, we found that isorhamnetin, a natural flavonoid compound without activity against S. suis, could significantly reduce the S. suis-stimulated production of the inflammatory cytokines interleukin (IL)-1ß, IL-6, and tumor necrosis factor alpha (TNF-α) and down-regulate the inflammatory response by inhibiting the activation of p38 and ERK in tissues infected with S. suis, thereby exerting protection against S. suis infection. The above findings suggest that isorhamnetin is a potential lead compound for the treatment of S. suis infections, thus laying a preliminary theoretical foundation for the further development of isorhamnetin as a candidate drug.
Assuntos
Antibacterianos/farmacologia , Quercetina/análogos & derivados , Streptococcus suis/efeitos dos fármacos , Streptococcus suis/patogenicidade , Animais , Western Blotting , Linhagem Celular , Inflamação/metabolismo , Cinética , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Macrófagos/metabolismo , Camundongos , Quercetina/farmacologia , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismoRESUMO
The classic NLRP3 inflammasome and NF-κB molecular pathways are activated in many inflammatory-related diseases, such as pleurisy. Because oridonin (Ori) has been indicated as a covalent NLRP3 inhibitor with strong anti-inflammasome activity, we herein aimed to assess the effects of Ori in a mouse model of carrageenan (CAR)-induced pleurisy. The results showed that CAR caused hemorrhaging and exudation of lung tissues and the release of inflammatory factors (TNF-α, IL-6 and IL-1ß), effects that were significantly reduced by treatment with Ori. In addition, increased neutrophil infiltration, protein concentrations and volumes were found in the exudates of the CAR group, and these phenomena were suppressed by Ori treatment. Regarding cellular pathways, Ori could alleviate the CAR-activated NF-κB and TXNIP/NLRP3 pathways. Additionally, oxidative stress was shown to be involved in the pathogenesis of pleurisy, but possible mechanisms remain to be explored. Herein, Ori reversed the CAR-induced depletion of GSH and SOD and the CAR-induced increases in ROS, MPO and MDA levels. Furthermore, Ori inhibited NOX-4 levels, initiated the dissociation of KEAP-1 from Nrf2, activated the downstream genes HO-1 and exerted antioxidative effects on CAR-induced pleurisy. In conclusion, Ori conferred protection against CAR-induced pleurisy via Nrf2-dependent antioxidative and NLRP3-dependent anti-inflammatory properties.
Assuntos
Anti-Inflamatórios/farmacologia , Antioxidantes/farmacologia , Diterpenos do Tipo Caurano/farmacologia , Pleurisia/prevenção & controle , Animais , Carragenina , Proteínas de Transporte/metabolismo , Modelos Animais de Doenças , Feminino , Inflamassomos/metabolismo , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Fator 2 Relacionado a NF-E2/metabolismo , NF-kappa B/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Pleurisia/patologia , Tiorredoxinas/metabolismoRESUMO
6'-O-galloylpaeoniflorin (GPF), a galloylated derivative of paeoniflorin isolated from peony root, has been proven to possess antioxidant potential. In this present study, we revealed that GPF treatment exerted significant neuroprotection of PC12 cells following OGD, as evidenced by a reduction of oxidative stress, inflammatory response, cellular injury, and apoptosis in vitro. Furthermore, treatment with GPF increased the levels of phosphorylated Akt (p-Akt) and nuclear factor-erythroid 2-related factor 2 (Nrf2), as well as promoted Nrf2 translocation in PC12 cells, which could be inhibited by Ly294002, an inhibitor of phosphoinositide 3-kinase (PI3K). In addition, Nrf2 knockdown or Ly294002 treatment significantly attenuated the antioxidant, anti-inflammatory, and antiapoptotic activities of GPF in vitro. In vivo studies indicated that GPF treatment significantly reduced infarct volume and improved neurological deficits in rats subjected to CIRI, as well as decreased oxidative stress, inflammation, and apoptosis, which could be inhibited by administration of Ly294002. In conclusion, these results revealed that GPF possesses neuroprotective effects against oxidative stress, inflammation, and apoptosis after ischemia-reperfusion insult via activation of the PI3K/Akt/Nrf2 pathway.
Assuntos
Isquemia Encefálica/tratamento farmacológico , Compostos Bicíclicos Heterocíclicos com Pontes/uso terapêutico , Glucosídeos/uso terapêutico , Monoterpenos/uso terapêutico , Fármacos Neuroprotetores/uso terapêutico , Células PC12/metabolismo , Traumatismo por Reperfusão/tratamento farmacológico , Animais , Isquemia Encefálica/patologia , Compostos Bicíclicos Heterocíclicos com Pontes/farmacologia , Linhagem Celular Tumoral , Glucosídeos/farmacologia , Masculino , Monoterpenos/farmacologia , Fármacos Neuroprotetores/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt , Ratos , Ratos WistarRESUMO
Acute lung injury (ALI)/acute respiratory distress syndrome (ARDS) is a common clinical syndrome of diffuse lung inflammation with high mortality rates and limited therapeutic methods. Diosmetin, an active component from Chinese herbs, has long been noticed because of its antioxidant and anti-inflammatory activities. The aim of this study was to evaluate the effects of diosmetin on LPS-induced ALI model and unveil the possible mechanisms. Our results revealed that pretreatment with diosmetin effectively alleviated lung histopathological changes, which were further evaluated by lung injury scores. Diosmetin also decreased lung wet/dry ratios, as well as total protein levels, inflammatory cell infiltration and proinflammatory cytokine (eg. TNF-α, IL-1ß and IL-6) overproduction in bronchoalveolar lavage fluid (BALF). Additionally, increased MPO, MDA and ROS levels induced by LPS were also markly suppressed by diosmetin. Furthermore, diosmetin significantly increased the expression of Nrf2 along with its target gene HO-1 and blocked the activation of NLRP3 inflammasome in the lung tissues, which might be central to the protective effects of diosmetin. Further supporting these results, in vitro experiments also showed that diosmetin activated Nrf2 and HO-1, as well as inhibited the NLRP3 inflammasome in both RAW264.7 and A549 cells. The present study highlights the protective effects of diosmetin on LPS-induced ALI via activation of Nrf2 and inhibition of NLRP3 inflammasome, bringing up the hope of its application as a therapeutic drug towards LPS-induced ALI.
RESUMO
Among the cellular response mechanisms, the nuclear factor erythroid-2 related factor 2 (Nrf2) pathway is considered a survival pathway that alleviates oxidative injury, while both the NOD-like receptor protein 3 (NLRP3) and NF-κB pathways are pro-inflammatory pathways that cause damage to cells. These pathways are implicated in the development and resolution of acute lung injury (ALI). Isoliquiritigenin (ISL), a flavonoid from the liquorice compound, is suggested to be a regulator of the above pathways, but the mechanisms of how the NLRP3/NF-κB pathway interacts with Nrf2 and its protective effects in ALI remain unknown. In the present study, ISL inhibited reactive oxygen species (ROS) generation and cytotoxicity induced by t-BHP and pro-inflammatory enzymes production induced by LPS in RAW 264.7 cells. Such cytoprotective effects coincided with the induction of AMP-activated protein kinase (AMPK)/Nrf2/antioxidant response element (ARE) signaling and the suppression of the NLRP3 and NF-κB pathways. Consistent with these findings, ISL treatment significantly alleviated lung injury in LPS-induced ALI mice, which was reflected by reductions in histopathological changes, pulmonary edema, and protein leakage. At the same time, the increased levels of inflammatory cell exudation and pro-inflammatory mediators, the enhanced production of ROS, myeloperoxidase, and malondialdehyde, and the depleted expression of GSH and superoxide dismutase induced by LPS were ameliorated by ISL. Furthermore, ISL notably activated AMPK/Nrf2/ARE signaling and inhibited LPS-induced NLRP3 and NF-κB activation in the lung. Moreover, although inhibition of the LPS-induced histopathological changes and ROS production were attenuated in Nrf2-deficient mice, the repression of the NLRP3 and NF-κB pathways by ISL was Nrf2-dependent and Nrf2-independent, respectively. In conclusion, our results are the first to highlight the beneficial role and relevant mechanisms of ISL in LPS-induced ALI and provide novel insight into its application.
RESUMO
Lung cancer is a leading cause of cancer-associated mortality worldwide, which has a low survival rate. Multidrug resistance (MDR) is a major obstacle that hinders the treatment of lung cancer. Doxorubicin (DOX) is an anthracycline glycoside antibiotic, having a broad spectrum of anticancer activity against various solid tumors. Juglanin is a natural production, mainly extracted from green walnut husks of Juglans mandshurica, exhibiting various bioactivities. Here, we demonstrated that the combination of drug, gene and nanoparticle overcame MDR, inhibiting lung cancer progression. A novel nanoparticular pre-chemosensitizer was applied to develop a self-assembled nanoparticle formula of amphiphilic poly(juglanin (Jug) dithiodipropionic acid (DA))-b-poly(ethylene glycol) (PEG)-siRNA Kras with DOX in the core (DOX/PJAD-PEG-siRNA). The formed nanoparticles, appeared spherical shape, had mean particle size of 81.8 nm, and the zeta potential was -18.62 mV. The in vitro drug release results suggested that a sustained release was observed in DOX/PJAD-PEG-siRNA nanoparticles compared to the free DOX. Jug could improve the cytotoxicity of DOX to cancer cells with MDR. Oncogene, Kras, was dose-dependently reduced by treatment of DOX/PJAD-PEG-siRNA nanoparticles. Additionally, P-glycoprotein (MDR1) and c-Myc, contributing to tumor progression, were suppressed by the nanoparticles, while p53 was improved in drug-resistant cells. Colony formation analysis suggested that DOX/PJAD-PEG-siRNA nanoparticles showed the most effective role in reducing cancer cell proliferation. In vivo, DOX/PJAD-PEG-siRNA nanoparticles reduced tumor growth compared to the free DOX, accompanied with reduced KI-67 and enhanced TUNEL positive levels in drug-resistant xenografted nude mice. Thus, the findings above indicated that juglanin, as a chemosensitizer, potentiate the anti-cancer role of DOX in drug-resistant cancer cells. And the nanoparticles exhibited stronger antitumor efficiency, suggesting potential value in the treatment of lung cancer.
Assuntos
Doxorrubicina/administração & dosagem , Glicosídeos/administração & dosagem , Quempferóis/administração & dosagem , Neoplasias Pulmonares/terapia , Proteínas Proto-Oncogênicas p21(ras)/antagonistas & inibidores , Proteínas Proto-Oncogênicas p21(ras)/genética , RNA Interferente Pequeno/administração & dosagem , Células A549 , Animais , Antibióticos Antineoplásicos/administração & dosagem , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Portadores de Fármacos/administração & dosagem , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos , Resistência a Múltiplos Medicamentos , Resistencia a Medicamentos Antineoplásicos , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Masculino , Camundongos , Camundongos Nus , Nanopartículas/administração & dosagem , Nanopartículas/química , Nanopartículas/ultraestrutura , Nanotecnologia , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
Abundant natural flavonoids can induce nuclear factor-erythroid 2 related factor 2 (Nrf2) and/or AMP-activated protein kinase (AMPK) activation, which play crucial roles in the amelioration of various inflammation- and oxidative stress-induced diseases, including acute lung injury (ALI). Xanthohumol (Xn), a principal prenylflavonoid, possesses anti-inflammation and anti-oxidant activities. However, whether Xn could protect from LPS-induced ALI through inducing AMPK/Nrf2 activation and its downstream signals, are still poorly elucidated. Accordingly, we focused on exploring the protective effect of Xn in the context of ALI and the involvement of underlying molecular mechanisms. Our findings indicated that Xn effectively alleviated lung injury by reduction of lung W/D ratio and protein levels, neutrophil infiltration, MDA and MPO formation, and SOD and GSH depletion. Meanwhile, Xn significantly lessened histopathological changes, reactive oxygen species (ROS) generation, several cytokines secretion, and iNOS and HMGB1 expression, and inhibited Txnip/NLRP3 inflammasome and NF-κB signaling pathway activation. Additionally, Xn evidently decreased t-BHP-stimulated cell apoptosis, ROS generation and GSH depletion but increased various anti-oxidative enzymes expression regulated by Keap1-Nrf2/ARE activation, which may be associated with AMPK and GSK3ß phosphorylation. However, Xn-mediated inflammatory cytokines and ROS production, histopathological changes, Txnip/NLRP3 inflammasome and NF-κB signaling pathway in WT mice were remarkably abrogated in Nrf2-/- mice. Our experimental results firstly provided a support that Xn effectively protected LPS-induced ALI against oxidative stress and inflammation damage which are largely dependent upon upregulation of the Nrf2 pathway via activation of AMPK/GSK3ß, thereby suppressing LPS-activated Txnip/NLRP3 inflammasome and NF-κB signaling pathway.
Assuntos
Lesão Pulmonar Aguda/tratamento farmacológico , Anti-Inflamatórios/administração & dosagem , Flavonoides/administração & dosagem , Lipopolissacarídeos/efeitos adversos , Propiofenonas/administração & dosagem , Transdução de Sinais/efeitos dos fármacos , Lesão Pulmonar Aguda/induzido quimicamente , Adenilato Quinase/metabolismo , Animais , Anti-Inflamatórios/farmacologia , Citocinas/metabolismo , Modelos Animais de Doenças , Flavonoides/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Glicogênio Sintase Quinase 3 beta/metabolismo , Camundongos , Fator 2 Relacionado a NF-E2/metabolismo , Propiofenonas/farmacologia , Espécies Reativas de Oxigênio/metabolismoRESUMO
Exposure to particulate matter (PM) with an aerodynamic diameter≤2.5µm (PM2.5) induces reactive oxygen species (ROS) and pro-inflammatory cytokine production, leading to airway epithelial injury. However, the mechanisms underlying the toxicity of PM2.5 have not been clarified. Here, we show that exposure to PM2.5 induces sustained activation of the nuclear factor kappa B (NF-κB) signaling in human airway epithelial Beas-2B (B2B) cells. In addition, PM2.5 exposure significantly decreased miR-331 expression in B2B cells, which was abrogated by inhibition of ROS or phosphoinositide 3-kinase (PI3K)/Akt pathway. Induction of miR-331 overexpression attenuated the PM2.5 exposure-induced NF-kBp65 nuclear translocation, IL-6 and IL-8 expression in B2B cells. Furthermore, miR-331 targeted the inhibitor of NF-κB kinase beta (IKK-ß) by down-regulating the IKK-ß-regulated luciferase activity in HEK293 cells. Moreover, induction of miR-331 over-expression inhibited IKK-ß expression while induction of IKK-ß over-expression prevented the inhibition of miR-331 on the PM2.5 exposure-induced NF-kBp65 nuclear translocation, IL-6 and IL-8 expression in B2B cells. Therefore, PM2.5 exposure decreased miR-331 expression via the ROS/PI3K/Akt pathway, resulting in an increase in the IKK-ß expression and sustained NF-κB activation in human airway epithelial cells. Our findings may provide new insights into the molecular mechanisms underlying the toxicity of PM2.5 exposure and aid in design of new therapeutic strategies to prevent PM2.5-induced toxicity.
Assuntos
Células Epiteliais/efeitos dos fármacos , MicroRNAs/genética , NF-kappa B/metabolismo , Material Particulado/toxicidade , Linhagem Celular , Células Epiteliais/citologia , Células Epiteliais/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Células HEK293 , Humanos , Quinase I-kappa B/genética , NF-kappa B/genética , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacosRESUMO
RATIONALE: With combination of multiple techniques, we have successfully characterized unique, complex chromosomal changes in a patient with chronic lymphocytic leukemia (CLL), a lymphoproliferative disorder. DIAGNOSES: The diagnosis was based on white blood cell, flow cytometry, and immunophenotypes and confirmed by karyotype, fluorescence in situ hybridization, and array comparative genomic hybridization from the patient's blood culture. INTERVENTIONS: The patient was given fludarabine, cyclophosphamide and rituximab (FCR) for 6 cycles. OUTCOMES: After completion of 6 cycles of FCR, the computed tomography scans of the neck/chest/abdomen/pelvic showed that the patient in CR. During the 10-month follow-up, the patient's clinical course remained uneventful. LESSONS: The translocation t(14;19) identified in this patient is a recurrent translocation found in patients with chronic B-cell lymphoproliferative disorders and the 3-way translocation involving chromosomes 2, 14, and 11 may play a role as an enhancer.