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1.
Nat Commun ; 14(1): 5311, 2023 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-37658047

RESUMO

The rapid emergence of antimicrobial resistance (AMR) pathogens highlights the urgent need to approach this global burden with alternative strategies. Cefiderocol (Fetroja®) is a clinically-used sideromycin, that is utilized for the treatment of severe drug-resistant infections, caused by Gram-negative bacteria; there is evidence of cefiderocol-resistance occurring in bacterial strains however. To increase the efficacy and extend the life-span of sideromycins, we demonstrate strong synergisms between cefiderocol and metallodrugs (e.g., colloidal bismuth citrate (CBS)), against Pseudomonas aeruginosa and Burkholderia cepacia. Moreover, CBS enhances cefiderocol efficacy against biofilm formation, suppresses the resistance development in P. aeruginosa and resensitizes clinically isolated resistant P. aeruginosa to cefiderocol. Notably, the co-therapy of CBS and cefiderocol significantly increases the survival rate of mice and decreases bacterial loads in the lung in a murine acute pneumonia model. The observed phenomena are partially attributable to the competitive binding of Bi3+ to cefiderocol with Fe3+, leading to enhanced uptake of Bi3+ and reduced levels of Fe3+ in cells. Our studies provide insight into the antimicrobial potential of metallo-sideromycins.


Assuntos
Antibacterianos , Farmacorresistência Bacteriana , Camundongos , Animais , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Carga Bacteriana , Pseudomonas aeruginosa , Cefiderocol
2.
Emerg Microbes Infect ; 12(2): 2254415, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37671453

RESUMO

Staphylococcus aureus is a major human pathogen responsible for a wide range of clinical infections. SaeRS is one of the two-component systems in S. aureus that modulate multiple virulence factors. Although SaeR is required for S. aureus to develop an infection, inhibitors have not been reported. Using an in vivo knockdown method, we demonstrated that SaeR is targetable for the discovery of antivirulence agent. HR3744 was discovered through a high-throughput screening utilizing a GFP-Lux dual reporter system driven by saeP1 promoter. The antivirulence efficacy of HR3744 was tested using Western blot, Quantitative Polymerase Chain Reaction, leucotoxicity, and haemolysis tests. In electrophoresis mobility shift assay, HR3744 inhibited SaeR-DNA probe binding. WaterLOGSY-NMR test showed HR3744 directly interacted with SaeR's DNA-binding domain. When SaeR was deleted, HR3744 lost its antivirulence property, validating the target specificity. Virtual docking and mutagenesis were used to confirm the target's specificity. When Glu159 was changed to Asn, the bacteria developed resistance to HR3744. A structure-activity relationship study revealed that a molecule with a slight modification did not inhibit SaeR, indicating the selectivity of HR3744. Interestingly, we found that SAV13, an analogue of HR3744, was four times more potent than HR3744 and demonstrated identical antivirulence properties and target specificity. In a mouse bacteraemia model, both HR3744 and SAV13 exhibited in vivo effectiveness. Collectively, we identified the first SaeR inhibitor, which exhibited in vitro and in vivo antivirulence properties, and proved that SaeR could be a novel target for developing antivirulence drugs against S. aureus infections.


Assuntos
Bacteriemia , Infecções Estafilocócicas , Humanos , Animais , Camundongos , Staphylococcus aureus/genética , Infecções Estafilocócicas/tratamento farmacológico , Western Blotting , Modelos Animais de Doenças
3.
Int J Mol Sci ; 24(7)2023 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-37047217

RESUMO

Antibiotic tolerance poses a threat to current antimicrobial armamentarium. Bacteria at a tolerant state survive in the presence of antibiotic treatment and account for persistence, relapse and recalcitrance of infections. Antibiotic treatment failure may occur due to antibiotic tolerance. Persistent infections are difficult to treat and are often associated with poor prognosis, imposing an enormous burden on the healthcare system. Effective strategies targeting antibiotic-tolerant bacteria are therefore highly warranted. In this study, small molecule compound SA-558 was identified to be effective against Staphylococcus aureus that are tolerant to being killed by conventional antibiotics. SA-558 mediated electroneutral transport across the membrane and led to increased ATP and ROS generation, resulting in a reduction of the population of antibiotic-tolerant bacteria. In a murine chronic infection model, of which vancomycin treatment failed, we demonstrated that SA-558 alone and in combination with vancomycin caused significant reduction of MRSA abundance. Our results indicate that SA-558 monotherapy or combinatorial therapy with vancomycin is an option for managing persistent S. aureus bacteremia infection and corroborate that bacterial metabolism is an important target for counteracting antibiotic tolerance.


Assuntos
Staphylococcus aureus Resistente à Meticilina , Infecções Estafilocócicas , Humanos , Animais , Camundongos , Antibacterianos/uso terapêutico , Staphylococcus aureus/metabolismo , Vancomicina/farmacologia , Infecções Estafilocócicas/tratamento farmacológico , Infecções Estafilocócicas/microbiologia , Bactérias , Trifosfato de Adenosina/metabolismo , Testes de Sensibilidade Microbiana
4.
Chem Sci ; 13(42): 12445-12460, 2022 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-36382278

RESUMO

Multidrug-resistant bacterial pathogens pose an increasing threat to human health. Certain bacteria, such as Staphylococcus aureus, are able to survive within professional phagocytes to escape the bactericidal effects of antibiotics and evade killing by immune cells, potentially leading to chronic or persistent infections. By investigating the macrophage response to S. aureus infection, we may devise a strategy to prime the innate immune system to eliminate the infected bacteria. Here we applied untargeted tandem mass spectrometry to characterize the lipidome alteration in S. aureus infected J774A.1 macrophage cells at multiple time points. Linoleic acid (LA) metabolism and sphingolipid metabolism pathways were found to be two major perturbed pathways upon S. aureus infection. The subsequent validation has shown that sphingolipid metabolism suppression impaired macrophage phagocytosis and enhanced intracellular bacteria survival. Meanwhile LA metabolism activation significantly reduced intracellular S. aureus survival without affecting the phagocytic capacity of the macrophage. Furthermore, exogenous LA treatment also exhibited significant bacterial load reduction in multiple organs in a mouse bacteremia model. Two mechanisms are proposed to be involved in this progress: exogenous LA supplement increases downstream metabolites that partially contribute to LA's capacity of intracellular bacteria-killing and LA induces intracellular reactive oxygen species (ROS) generation through an electron transport chain pathway in multiple immune cell lines, which further increases the capacity of killing intracellular bacteria. Collectively, our findings not only have characterized specific lipid pathways associated with the function of macrophages but also demonstrated that exogenous LA addition may activate lipid modulator-mediated innate immunity as a potential therapy for bacterial infections.

5.
Int J Biol Sci ; 18(12): 4744-4755, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35874954

RESUMO

Viruses exploit the host lipid metabolism machinery to achieve efficient replication. We herein characterize the lipids profile reprogramming in vitro and in vivo using liquid chromatography-mass spectrometry-based untargeted lipidomics. The lipidome of SARS-CoV-2-infected Caco-2 cells was markedly different from that of mock-infected samples, with most of the changes involving downregulation of ceramides. In COVID-19 patients' plasma samples, a total of 54 lipids belonging to 12 lipid classes that were significantly perturbed compared to non-infected control subjects' plasma samples were identified. Among these 12 lipid classes, ether-linked phosphatidylcholines, ether-linked phosphatidylethanolamines, phosphatidylcholines, and ceramides were the four most perturbed. Pathway analysis revealed that the glycerophospholipid, sphingolipid, and ether lipid metabolisms pathway were the most significantly perturbed host pathways. Phosphatidic acid phosphatases (PAP) were involved in all three pathways and PAP-1 deficiency significantly suppressed SARS-CoV-2 replication. siRNA knockdown of LPIN2 and LPIN3 resulted in significant reduction of SARS-CoV-2 load. In summary, these findings characterized the host lipidomic changes upon SARS-CoV-2 infection and identified PAP-1 as a potential target for intervention for COVID-19.


Assuntos
COVID-19 , SARS-CoV-2 , Células CACO-2 , Ceramidas , Éteres , Glicerofosfolipídeos , Humanos , Metabolismo dos Lipídeos , Fosfatidato Fosfatase/genética , Fosfatidato Fosfatase/metabolismo , Fosfatidilcolinas/metabolismo , Fosfatidiletanolaminas/metabolismo
6.
Antibiotics (Basel) ; 11(6)2022 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-35740225

RESUMO

Staphylococcus aureus can cause a plethora of life-threatening infections. Antibiotics have been extensively used to treat S. aureus infections. However, when antibiotics are used at sub-inhibitory concentrations, especially for ß-lactam antibiotics, they may enhance staphylococcal pathogenicity and exacerbate the infection. The combination of antivirulence agents and antibiotics may be a novel approach to controlling antibiotic-induced S. aureus pathogenicity. We have illustrated that under in vitro conditions, antivirulence agent M21, when administered concurrently with ampicillin, suppressed the expression and production of virulence factors induced by ampicillin. In a mouse peritonitis model, M21 reduced bacterial load irrespective of administration of ampicillin. In a bacteremia model, combinatorial treatment consisting of ampicillin or ceftazidime and M21 increased the survival rate of mice and reduced cytokine abundance, suggesting the suppression of antibiotic-induced virulence by M21. Different from traditional antibiotic adjuvants, an antivirulence agent may not synergistically inhibit bacterial growth in vitro, but effectively benefit the host in vivo. Collectively, our findings from this study demonstrated the benefits of antivirulence-antibiotic combinatorial treatment against S. aureus infections and provide a new perspective on the development of antibiotic adjuvants.

7.
Microbiol Spectr ; 10(4): e0064022, 2022 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-35758685

RESUMO

Antibiotics are widely used for the treatment of bacterial infections. However, injudicious use of antibiotics based on an empirical method may lead to the emergence of resistant strains. Despite appropriate administration of antibiotics, their concentrations may remain subinhibitory in the body, due to individual variations in tissue distribution and metabolism rates. This may promote bacterial virulence and complicate the treatment strategies. To investigate whether the administration of certain classes of antibiotics will induce bacterial virulence and worsen the infection under in vivo conditions. Different classes of antibiotics were tested in vitro for their ability to induce virulence in a methicillin-resistant S. aureus strain Mu3 and clinical isolates. Antibiotic-induced pathogenicity was assessed in vivo using mouse peritonitis and bacteremia models. In vitro, ß-lactam antibiotics and tetracyclines induced the expression of multiple surface-associated virulence factors as well as the secretion of toxins. In peritonitis and bacteremia models, mice infected with MRSA and treated with ampicillin, ceftazidime, or tetracycline showed enhanced bacterial pathogenicity. The release of induced virulence factors in vivo was confirmed in a histological examination. Subinhibitory concentrations of antibiotics belonging to ß-lactam and tetracycline aggravated infection by inducing staphylococcal virulence in vivo. Thus, when antibiotics are required, it is preferable to employ combination therapy and to initiate the appropriate treatment plan, following diagnosis. Our findings emphasize the risks associated with antibiotic-based therapy and underline the need for alternative therapeutic options. IMPORTANCE Antibiotics are widely applied to treat infectious diseases. Empirically treatment with incorrect antibiotics, or even correct antibiotics always falls into subinhibitory concentrations, due to dosing, distribution, or secretion. In this study, we have systematically evaluated in vitro virulence induction effect of antibiotics and in vivo exacerbated infection. The major highlight of this work is to prove the ß-lactam and tetracyclines antibiotics exacerbated disease is due to their induction effect on staphylococcal virulence. This phenomenon is common and suggests that if ß-lactam antibiotics remain the first line of defense during empirical therapy, we either need to increase patient reliability or the treatment approach may improve in the future when paired with anti-virulence drugs.


Assuntos
Bacteriemia , Staphylococcus aureus Resistente à Meticilina , Peritonite , Infecções Estafilocócicas , Animais , Antibacterianos/farmacologia , Bacteriemia/tratamento farmacológico , Camundongos , Testes de Sensibilidade Microbiana , Peritonite/tratamento farmacológico , Reprodutibilidade dos Testes , Infecções Estafilocócicas/tratamento farmacológico , Infecções Estafilocócicas/microbiologia , Tetraciclina/farmacologia , Fatores de Virulência , beta-Lactamas/farmacologia
8.
Antibiotics (Basel) ; 11(3)2022 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-35326832

RESUMO

The emergence of multidrug-resistant strains and hyper-virulent strains of Mycobacterium tuberculosis are big therapeutic challenges for tuberculosis (TB) control. Repurposing bioactive small-molecule compounds has recently become a new therapeutic approach against TB. This study aimed to identify novel anti-TB agents from a library of small-molecule compounds via a rapid screening system. A total of 320 small-molecule compounds were used to screen for their ability to suppress the expression of a key virulence gene, phop, of the M. tuberculosis complex using luminescence (lux)-based promoter-reporter platforms. The minimum inhibitory and bactericidal concentrations on drug-resistant M. tuberculosis and cytotoxicity to human macrophages were determined. RNA sequencing (RNA-seq) was conducted to determine the drug mechanisms of the selected compounds as novel antibiotics or anti-virulent agents against the M. tuberculosis complex. The results showed that six compounds displayed bactericidal activity against M. bovis BCG, of which Ebselen demonstrated the lowest cytotoxicity to macrophages and was considered as a potential antibiotic for TB. Another ten compounds did not inhibit the in vitro growth of the M. tuberculosis complex and six of them downregulated the expression of phoP/R significantly. Of these, ST-193 and ST-193 (hydrochloride) showed low cytotoxicity and were suggested to be potential anti-virulence agents for M. tuberculosis.

9.
Emerg Microbes Infect ; 11(1): 926-937, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35259078

RESUMO

Pandemic influenza virus and SARS-CoV-2 vaiants have posed major global threats to public health. Broad-spectrum antivirals blocking viral entry can be an effective strategy for combating these viruses. Here, we demonstrate a frog-defensin-derived basic peptide (FBP), which broadly inhibits the influenza virus by binding to haemagglutinin so as to block low pH-induced HA-mediated fusion and antagonizes endosomal acidification to inhibit the influenza virus. Moreover, FBP can bind to the SARS-CoV-2 spike to block spike-mediated cell-cell fusion in 293T/ACE2 cells endocytosis. Omicron spike shows a weak cell-cell fusion mediated by TMPRSS2 in Calu3 cells, making the Omicron variant sensitive to endosomal inhibitors. In vivo studies show that FBP broadly inhibits the A(H1N1)pdm09 virus in mice and SARS-CoV-2 (HKU001a and Delta)in hamsters. Notably, FBP shows significant inhibition of Omicron variant replication even though it has a high number of mutations in spike. In conclusion, these results suggest that virus-targeting FBP with a high barrier to drug resistance can be an effective entry-fusion inhibitor against influenza virus and SARS-CoV-2 in vivo.


Assuntos
Tratamento Farmacológico da COVID-19 , Vírus da Influenza A Subtipo H1N1 , Animais , Camundongos , Peptídeos , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus/genética , Glicoproteína da Espícula de Coronavírus/metabolismo
12.
EBioMedicine ; 70: 103505, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34332295

RESUMO

BACKGROUND: Staphylococcus aureus is a common human pathogen capable of causing diverse illnesses with possible recurrent infections. Although recent studies have highlighted the role of cellular immunity in recurrent infections, the mechanism by which S. aureus evades host responses remains largely unexplored. METHODS: This study utilizes in vitro and in vivo infection experiments to investigate difference of pro-inflammatory responses and subsequent adaptive immune responses between adsA mutant and WT S. aureus strain infection. FINDINGS: We demonstrated that adenosine synthase A (AdsA), a potent S. aureus virulence factor, can alter Th17 responses by interfering with NLRP3 inflammasome-mediated IL-1ß production. Specifically, S. aureus virulence factor AdsA dampens Th1/Th17 immunity by limiting the release of IL-1ß and other Th polarizing cytokines. In particular, AdsA obstructs the release of IL-1ß via the adenosine/A2aR/NLRP3 axis. Using a murine infection model, pharmacological inhibition of A2a receptor enhanced S. aureus-specific Th17 responses, whereas inhibition of NLRP3 and caspase-1 downregulated these responses. Our results showed that AdsA contributes to recurrent S. aureus infection by restraining protective Th1/Th17 responses. INTERPRETATION: Our study provides important mechanistic insights for therapeutic and vaccination strategies against S. aureus infections. FUNDING: This work was supported by grants from Shenzhen Peacock project (KQTD2015033-117210153), and Guangdong Science and Technology Department (2020B1212030004) to J.H. and China Postdoctoral Science Foundation (2019M663167) to BZZ. We also thank the L & T Charitable Foundation, the Guangdong Science and Technology Department (2020B1212030004), and the Program for Guangdong Introducing Innovative and Entrepreneurial Teams (2019BT02Y198) for their support.


Assuntos
Proteínas de Bactérias/imunologia , Infecções Estafilocócicas/imunologia , Staphylococcus aureus/enzimologia , Fatores de Virulência/imunologia , Adenosina/biossíntese , Animais , Células Cultivadas , Feminino , Humanos , Evasão da Resposta Imune , Interleucina-1beta/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Receptor A2A de Adenosina/metabolismo , Infecções Estafilocócicas/microbiologia , Staphylococcus aureus/imunologia , Staphylococcus aureus/patogenicidade , Células THP-1 , Células Th17/imunologia
13.
Nat Commun ; 12(1): 3331, 2021 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-34099682

RESUMO

The rapid emergence of drug resistant Staphylococcus aureus (S. aureus) poses a serious threat to public health globally. Silver (Ag)-based antimicrobials are promising to combat antibiotic resistant S. aureus, yet their molecular targets are largely elusive. Herein, we separate and identify 38 authentic Ag+-binding proteins in S. aureus at the whole-cell scale. We then capture the molecular snapshot on the dynamic action of Ag+ against S. aureus and further validate that Ag+ could inhibit a key target 6-phosphogluconate dehydrogenase through binding to catalytic His185 by X-ray crystallography. Significantly, the multi-target mode of action of Ag+ (and nanosilver) endows its sustainable antimicrobial efficacy, leading to enhanced efficacy of conventional antibiotics and resensitization of MRSA to antibiotics. Our study resolves the long-standing question of the molecular targets of silver in S. aureus and offers insights into the sustainable bacterial susceptibility of silver, providing a potential approach for combating antimicrobial resistance.


Assuntos
Antibacterianos/farmacologia , Farmacorresistência Bacteriana/efeitos dos fármacos , Nanopartículas Metálicas/química , Prata/farmacologia , Staphylococcus aureus/efeitos dos fármacos , Cristalografia por Raios X , Staphylococcus aureus Resistente à Meticilina , Testes de Sensibilidade Microbiana , Fosfogluconato Desidrogenase/efeitos dos fármacos , Proteômica , Prata/química , Nitrato de Prata , Infecções Estafilocócicas
14.
J Am Chem Soc ; 143(18): 6886-6894, 2021 05 12.
Artigo em Inglês | MEDLINE | ID: mdl-33909441

RESUMO

Carbapenems stand as one of the last-resort antibiotics; however, their efficacy is threatened by the rising number and rapid spread of carbapenemases. Effective antimicrobial stewardship thus calls for rapid tests for these enzymes to aid appropriate prescription and infection control. Herein, we report the first effective pan-carbapenemase reporter CARBA-H with a broad scope covering all three Ambler classes. Using a chemical biology approach, we demonstrated that the absence of the 1ß-substituent in the carbapenem core is key to pan-carbapenemase recognition, which led to our rational design and probe development. CARBA-H provides a dual colorimetric-fluorogenic response upon carbapenemase-mediated hydrolysis. A clear visual readout can be obtained within 15 min when tested against a panel of carbapenemase-producing Enterobacteriaceae (CPE) clinical isolates that notably includes OXA-48 and OXA-181-producing strains. Furthermore, CARBA-H can be applied to the detection of carbapemenase activity in CPE-spiked urine samples.


Assuntos
Proteínas de Bactérias/análise , Colorimetria , Corantes Fluorescentes/química , beta-Lactamases/análise , Proteínas de Bactérias/metabolismo , Citrobacter freundii/enzimologia , Enterobacter aerogenes/enzimologia , Escherichia coli/enzimologia , Corantes Fluorescentes/síntese química , Klebsiella pneumoniae/enzimologia , Estrutura Molecular , beta-Lactamases/metabolismo
15.
Nat Commun ; 11(1): 5263, 2020 10 16.
Artigo em Inglês | MEDLINE | ID: mdl-33067430

RESUMO

Global emergence of Gram-negative bacteria carrying the plasmid-borne resistance genes, blaMBL and mcr, raises a significant challenge to the treatment of life-threatening infections by the antibiotics, carbapenem and colistin (COL). Here, we identify an antirheumatic drug, auranofin (AUR) as a dual inhibitor of metallo-ß-lactamases (MBLs) and mobilized colistin resistance (MCRs), two resistance enzymes that have distinct structures and substrates. We demonstrate that AUR irreversibly abrogates both enzyme activity via the displacement of Zn(II) cofactors from their active sites. We further show that AUR synergizes with antibiotics on killing a broad spectrum of carbapenem and/or COL resistant bacterial strains, and slows down the development of ß-lactam and COL resistance. Combination of AUR and COL rescues all mice infected by Escherichia coli co-expressing MCR-1 and New Delhi metallo-ß-lactamase 5 (NDM-5). Our findings provide potential therapeutic strategy to combine AUR with antibiotics for combating superbugs co-producing MBLs and MCRs.


Assuntos
Antibacterianos/administração & dosagem , Auranofina/administração & dosagem , Carbapenêmicos/farmacologia , Colistina/farmacologia , Infecções por Escherichia coli/tratamento farmacológico , Inibidores de beta-Lactamases/administração & dosagem , Animais , Farmacorresistência Bacteriana Múltipla , Escherichia coli/efeitos dos fármacos , Escherichia coli/enzimologia , Escherichia coli/genética , Infecções por Escherichia coli/microbiologia , Proteínas de Escherichia coli/antagonistas & inibidores , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Feminino , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Testes de Sensibilidade Microbiana , beta-Lactamases/genética , beta-Lactamases/metabolismo
16.
Cancers (Basel) ; 11(12)2019 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-31769432

RESUMO

Autophagy, a conserved cellular mechanism, is manipulated by a number of viruses for different purposes. We previously demonstrated that an iron-chelator-like small compound, C7, reactivates Epstein-Barr virus (EBV) lytic cycle by activating the ERK1/2-autophagy axis in epithelial cancers. Here, we aim to identify the specific stage of autophagy required for EBV lytic reactivation, determine the autophagy dependency of EBV lytic inducers including histone deacetylase inhibitor (HDACi) and C7/iron chelators, for EBV lytic reactivation and measure the combinatorial effects of these types of lytic inducers in nasopharyngeal carcinoma (NPC). Inhibition of autophagy initiation by 3-MA and autolysosome formation by chloroquine demonstrated that only autophagy initiation is required for EBV lytic reactivation. Gene knockdown of various autophagic proteins such as beclin-1, ATG5, ATG12, ATG7, LC3B, ATG10, ATG3 and Rab9, revealed the importance of ATG5 in EBV lytic reactivation. 3-MA could only abrogate lytic cycle induction by C7/iron chelators but not by HDACi, providing evidence for autophagy-dependent and independent mechanisms in EBV lytic reactivation. Finally, the combination of C7 and SAHA at their corresponding reactivation kinetics enhanced EBV lytic reactivation. These findings render new insights in the mechanisms of EBV lytic cycle reactivation and stimulate a rational design of combination drug therapy against EBV-associated cancers.

17.
Int J Mol Sci ; 20(23)2019 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-31779252

RESUMO

Enterovirus A71 (EV-A71) and coxsackievirus A16 (CV-A16) are the most common causes of hand, foot, and mouth disease. Severe EV-A71 and CV-A16 infections may be associated with life-threatening complications. However, the pathogenic mechanisms underlying these severe clinical and pathological features remain incompletely understood. Lipids are known to play critical roles in multiple stages of the virus replication cycle. The specific lipid profile induced upon virus infection is required for optimal virus replication. The perturbations in the host cell lipidomic profiles upon enterovirus infection have not been fully characterized. To this end, we performed ultra-high performance liquid chromatography-electrospray ionization-quadrupole-time of flight-mass spectrometry (UPLC-ESI-Q-TOF-MS)-based lipidomics to characterize the change in host lipidome upon EV-A71 and CV-A16 infections. Our results revealed that 47 lipids within 11 lipid classes were significantly perturbed after EV-A71 and CV-A16 infection. Four polyunsaturated fatty acids (PUFAs), namely, arachidonic acid (AA), docosahexaenoic acid (DHA), docosapentaenoic acid (DPA), and eicosapentaenoic acid (EPA), were consistently upregulated upon EV-A71 and CV-A16 infection. Importantly, exogenously supplying three of these four PUFAs, including AA, DHA, and EPA, in cell cultures significantly reduced EV-A71 and CV-A16 replication. Taken together, our results suggested that enteroviruses might specifically modulate the host lipid pathways for optimal virus replication. Excessive exogenous addition of lipids that disrupted this delicate homeostatic state could prevent efficient viral replication. Precise manipulation of the host lipid profile might be a potential host-targeting antiviral strategy for enterovirus infection.


Assuntos
Enterovirus Humano A/patogenicidade , Infecções por Enterovirus/metabolismo , Lipidômica/métodos , Linhagem Celular , Cromatografia Líquida de Alta Pressão , Enterovirus Humano A/classificação , Infecções por Enterovirus/virologia , Homeostase , Humanos , Análise de Componente Principal , Espectrometria de Massas por Ionização por Electrospray , Replicação Viral
18.
mSphere ; 4(5)2019 09 04.
Artigo em Inglês | MEDLINE | ID: mdl-31484738

RESUMO

The demand for a prophylactic vaccine against methicillin-resistant Staphylococcus aureus (MRSA) has motivated numerous dedicated research groups to design and develop such a vaccine. In this study, we have developed a multivalent vaccine, Sta-V5, composed of five conserved antigens involved in three important virulence mechanisms. This prototype vaccine conferred up to 100% protection against multiple epidemiologically relevant S. aureus isolates in five different murine disease models. The vaccine not only elicits functional antibodies that mediate opsonophagocytic killing of S. aureus but also mounts robust antigen-specific T-cell responses. In addition, our data implied that γδ T cells contribute to the protection induced by Sta-V5 in a murine skin infection model.IMPORTANCEStaphylococcus aureus infections, especially MRSA infections, are becoming a major global health issue and are resulting in mortality rates that are increasing every year. However, an effective vaccine is lacking due to the complexity of the infection process of S. aureus In this study, we found that the addition of two novel protein components to three well-studied vaccine candidates significantly improved the efficacy of the combined vaccine. Furthermore, the five-component vaccine not only elicits a robust antibody response but also induces cytokine secretion by T cells, making it a promising vaccine candidate to fill the void.


Assuntos
Anticorpos Antibacterianos/imunologia , Antígenos de Bactérias/imunologia , Infecções Estafilocócicas/prevenção & controle , Vacinas Antiestafilocócicas/imunologia , Animais , Proteínas de Bactérias/genética , Proteínas de Bactérias/imunologia , Citocinas/imunologia , Modelos Animais de Doenças , Feminino , Camundongos , Camundongos Endogâmicos BALB C , Sepse , Pele/imunologia , Pele/microbiologia , Infecções Estafilocócicas/imunologia , Vacinas Antiestafilocócicas/genética , Staphylococcus aureus
19.
Nat Commun ; 10(1): 120, 2019 01 10.
Artigo em Inglês | MEDLINE | ID: mdl-30631056

RESUMO

Viruses are obligate intracellular microbes that exploit the host metabolic machineries to meet their biosynthetic demands, making these host pathways potential therapeutic targets. Here, by exploring a lipid library, we show that AM580, a retinoid derivative and RAR-α agonist, is highly potent in interrupting the life cycle of diverse viruses including Middle East respiratory syndrome coronavirus and influenza A virus. Using click chemistry, the overexpressed sterol regulatory element binding protein (SREBP) is shown to interact with AM580, which accounts for its broad-spectrum antiviral activity. Mechanistic studies pinpoint multiple SREBP proteolytic processes and SREBP-regulated lipid biosynthesis pathways, including the downstream viral protein palmitoylation and double-membrane vesicles formation, that are indispensable for virus replication. Collectively, our study identifies a basic lipogenic transactivation event with broad relevance to human viral infections and represents SREBP as a potential target for the development of broad-spectrum antiviral strategies.


Assuntos
Benzoatos/farmacologia , Metabolismo dos Lipídeos/efeitos dos fármacos , Proteínas de Ligação a Elemento Regulador de Esterol/metabolismo , Tetra-Hidronaftalenos/farmacologia , Replicação Viral/efeitos dos fármacos , Antivirais/farmacologia , Benzoatos/química , Benzoatos/metabolismo , Vias Biossintéticas/efeitos dos fármacos , Vírus da Influenza A/efeitos dos fármacos , Vírus da Influenza A/fisiologia , Lipídeos/biossíntese , Coronavírus da Síndrome Respiratória do Oriente Médio/efeitos dos fármacos , Coronavírus da Síndrome Respiratória do Oriente Médio/fisiologia , Ligação Proteica , Retinoides/química , Retinoides/metabolismo , Retinoides/farmacologia , Tetra-Hidronaftalenos/química , Tetra-Hidronaftalenos/metabolismo , Viroses/prevenção & controle , Viroses/virologia
20.
Viruses ; 11(1)2019 01 16.
Artigo em Inglês | MEDLINE | ID: mdl-30654597

RESUMO

Lipids play numerous indispensable cellular functions and are involved in multiple steps in the replication cycle of viruses. Infections by human-pathogenic coronaviruses result in diverse clinical outcomes, ranging from self-limiting flu-like symptoms to severe pneumonia with extrapulmonary manifestations. Understanding how cellular lipids may modulate the pathogenicity of human-pathogenic coronaviruses remains poor. To this end, we utilized the human coronavirus 229E (HCoV-229E) as a model coronavirus to comprehensively characterize the host cell lipid response upon coronavirus infection with an ultra-high performance liquid chromatography-mass spectrometry (UPLC⁻MS)-based lipidomics approach. Our results revealed that glycerophospholipids and fatty acids (FAs) were significantly elevated in the HCoV-229E-infected cells and the linoleic acid (LA) to arachidonic acid (AA) metabolism axis was markedly perturbed upon HCoV-229E infection. Interestingly, exogenous supplement of LA or AA in HCoV-229E-infected cells significantly suppressed HCoV-229E virus replication. Importantly, the inhibitory effect of LA and AA on virus replication was also conserved for the highly pathogenic Middle East respiratory syndrome coronavirus (MERS-CoV). Taken together, our study demonstrated that host lipid metabolic remodeling was significantly associated with human-pathogenic coronavirus propagation. Our data further suggested that lipid metabolism regulation would be a common and druggable target for coronavirus infections.


Assuntos
Coronavirus Humano 229E/fisiologia , Interações Hospedeiro-Patógeno , Metabolismo dos Lipídeos , Replicação Viral , Ácido Araquidônico/metabolismo , Linhagem Celular , Cromatografia Líquida , Glicerofosfolipídeos/metabolismo , Humanos , Ácido Linoleico/metabolismo , Espectrometria de Massas em Tandem
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