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1.
Nat Commun ; 15(1): 1669, 2024 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-38396029

RESUMO

The bacterial pathogen Neisseria gonorrhoeae is able to invade epithelial cells and survive intracellularly. During this process, it secretes outer membrane vesicles (OMVs), however, the mechanistic details for interactions between gonococcal OMVs and epithelial cells and their impact on intracellular survival are currently not established. Here, we show that gonococcal OMVs induce epithelial cell mitophagy to reduce mitochondrial secretion of reactive oxygen species (ROS) and enhance intracellular survival. We demonstrate that OMVs deliver PorB to mitochondria to dissipate the mitochondrial membrane potential, resulting in mitophagy induction through a conventional PINK1 and OPTN/NDP52 mechanism. Furthermore, PorB directly recruits the E3 ubiquitin ligase RNF213, which decorates PorB lysine residue 171 with K63-linked polyubiquitin to induce mitophagy in a p62-dependent manner. These results demonstrate a mechanism in which polyubiquitination of a bacterial virulence factor that targets mitochondria directs mitophagy processes to this organelle to prevent its secretion of deleterious ROS.


Assuntos
Gonorreia , Mitofagia , Humanos , Espécies Reativas de Oxigênio/metabolismo , Mitocôndrias/metabolismo , Gonorreia/microbiologia , Células Epiteliais/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Adenosina Trifosfatases/metabolismo
2.
J Infect Dis ; 228(12): 1776-1788, 2023 12 20.
Artigo em Inglês | MEDLINE | ID: mdl-37926090

RESUMO

Neisseria gonorrhoeae establishes tight interactions with mucosal epithelia through activity of its type IV pilus, while pilus retraction forces activate autophagic responses toward invading gonococci. Here we studied pilus-independent epithelial cell responses and showed that pilus-negative gonococci residing in early and late endosomes are detected and targeted by nucleotide-binding oligomerization domain 1 (NOD1). NOD1 subsequently forms a complex with immunity-related guanosine triphosphatase M (IRGM) and autophagy-related 16-like 1 (ATG16L1) to activate autophagy and recruit microtubule-associated protein light chain 3 (LC3) to the intracellular bacteria. IRGM furthermore directly recruits syntaxin 17 (STX17), which is able to form tethering complexes with the lysosome. Importantly, IRGM-STX17 interactions are enhanced by LC3 but were still observed at lower levels in an LC3 knockout cell line. These findings demonstrate key roles for NOD1 and IRGM in the sensing of intracellular N gonorrhoeae and subsequent directing of the bacterium to the lysosome for degradation.


Assuntos
Autofagia , Neisseria gonorrhoeae , Neisseria gonorrhoeae/metabolismo , Células Epiteliais/metabolismo , Lisossomos/metabolismo , Proteínas Associadas aos Microtúbulos/metabolismo , Proteínas Qa-SNARE/genética , Proteínas Qa-SNARE/metabolismo , Endossomos/metabolismo
3.
Microbiol Spectr ; 11(6): e0244923, 2023 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-37982635

RESUMO

IMPORTANCE: Ceftriaxone-based antimicrobial therapies for gonorrhea are threatened by waning ceftriaxone susceptibility levels and the global dissemination of the high-level ceftriaxone-resistant gonococcal FC428 clone. Combination therapy can be an effective strategy to restrain the development of ceftriaxone resistance, and for that purpose, it is important to find an alternative antimicrobial to replace azithromycin, which has recently been removed in some countries from the recommended ceftriaxone plus azithromycin dual-antimicrobial therapy. Ideally, the second antimicrobial should display synergistic activity with ceftriaxone. We hypothesized that bacitracin might display synergistic activity with ceftriaxone because of their distinct mechanisms targeting bacterial cell wall synthesis. In this study, we showed that bacitracin indeed displays synergistic activity with ceftriaxone against Neisseria gonorrhoeae. Importantly, strains associated with the FC428 clone appeared to be particularly susceptible to the bacitracin plus ceftriaxone combination, which might therefore be an interesting dual therapy for further in vivo testing.


Assuntos
Ceftriaxona , Gonorreia , Humanos , Ceftriaxona/farmacologia , Gonorreia/tratamento farmacológico , Gonorreia/microbiologia , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Azitromicina , Bacitracina/farmacologia , Testes de Sensibilidade Microbiana , Neisseria gonorrhoeae , Farmacorresistência Bacteriana
4.
Emerg Microbes Infect ; 12(2): 2249124, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37584947

RESUMO

ABSTRACTGlobal dissemination of high-level ceftriaxone-resistant Neisseria gonorrhoeae strains associated with the FC428 clone poses a threat to the efficacy ceftriaxone-based therapies. Vaccination is the best strategy to contain multidrug-resistant infections. In this study, we investigated the efficacy of MtrE and its surface Loop2 as vaccine antigens when combined with a Th1-polarizing adjuvant, which is expected to be beneficial for gonococcal vaccine development. Using in vitro dendritic cell maturation and T cell differentiation assays, CpG1826 was identified as the optimal Th1-polarizing adjuvant for MtrE and Loop2 displayed as linear epitope (Nloop2) or structural epitope (Intraloop2) on a carrier protein. Loop2-based antigens raised strongly Th1-polarized and bactericidal antibody responses in vaccinated mice. Furthermore, the vaccine formulations provided protection against a gonococcal challenge in mouse vaginal tract infection model when provided as prophylactic vaccines. Also, the vaccine formulations accelerated gonococcal clearance when provided as a single therapeutic dose to treat an already established infection, including against a strain associated with the FC428 clone. Therefore, this study demonstrated that MtrE and Loop 2 are effective gonococcal vaccine antigens when combined with the Th1-polarizing CpG1826 adjuvant.


Assuntos
Ceftriaxona , Gonorreia , Feminino , Camundongos , Animais , Gonorreia/prevenção & controle , Vacinas Bacterianas , Neisseria gonorrhoeae/genética , Epitopos
5.
Stem Cell Res Ther ; 14(1): 147, 2023 05 29.
Artigo em Inglês | MEDLINE | ID: mdl-37248497

RESUMO

BACKGROUND: Atopic dermatitis (AD) is one of the most common immune and inflammatory skin disorders, leading to insufferable itching and skin abnormalities that seriously affect life quality of patients. There are still huge unmet needs for long-term and effective disease control, despite currently available therapies. Evidenced by some preclinical and clinical studies of AD treatment with stem cells, stem cell treatment could significantly and effectively ameliorate AD symptoms. OBJECTIVES: To elucidate underlying mechanisms of how stem cells therapy alleviates AD-like symptoms. METHODS: An AD-like mouse model was constructed and treated with mesenchymal stem cells (MSCs) subcutaneously or subcutaneously combined with intravenously. The differentially expressed genes were sorted out from RNA sequencing results of dorsal skin and blood. RESULTS: Two injection routes of MSCs could alleviate AD-like symptoms and pathologic changes of the skin and immune organs. RNA sequencing of dorsal skin sections and blood provided gene expression signatures for amelioration of skin defects, inflammatory and immune modulation by MSCs, as well as common AD molecular markers for the skin and blood, which may benefit for clinical diagnosis. IL-1ß and its signaling pathway were specifically found to be associated with the development of AD-like dermatitis lesions. MSC treatment effectively inhibited the JAK-STAT pathway and receptors of IL-4, IL-13, IL-17, and IgE. CONCLUSIONS: MSC therapy could regulate abnormal immune and inflammatory status in AD. Mechanistic exploration will contribute to the development of personalized AD treatment based on MSCs.


Assuntos
Dermatite Atópica , Células-Tronco Mesenquimais , Animais , Camundongos , Humanos , Dermatite Atópica/terapia , Janus Quinases/metabolismo , Transdução de Sinais , Fatores de Transcrição STAT/metabolismo , Pele/patologia , Fatores Imunológicos/farmacologia , Células-Tronco Mesenquimais/metabolismo , Cordão Umbilical/metabolismo , Citocinas/metabolismo
6.
Life Sci ; 326: 121788, 2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37230377

RESUMO

AIM: Psoriasis is one of the most common dermatological disorders, characterized by increased epidermal hyperplasia and immune cell infiltration. Psychological stress has been reported to contribute to the severity, aggravation, and relapse of psoriasis. However, the exact mechanism involved in psychological stress's impact on psoriasis is still unclear. We aim to investigate the role of psychological stress in psoriasis from a transcriptomic and metabolomic perspective. MAIN METHOD: We developed a chronic restrain stress (CRS)-imiquimod (IMQ)-induced psoriasis-like mouse model and performed a comprehensive comparative transcriptomic and metabolic analysis with control mice, CRS-treated mice, and IMQ-treated mice to investigate how psychological stress affects psoriasis. KEY FINDING: We found that CRS-IMQ-induced psoriasis-like mice showed significant exacerbation of psoriasis-like skin inflammation compared with mice treated with IMQ only. Mice of the CRS + IMQ group showed increased expression of keratinocyte proliferation and differentiation genes, differential regulation of cytokines, and promotion of linoleic acid metabolism. Correlation analysis of differentially expressed genes in the CRS-IMQ-induced psoriasis-like mice and human psoriasis datasets compared with respective controls revealed 96 overlapping genes of which 30 genes showed consistent induced or repressed expression in all human and mouse datasets. SIGNIFICANCE: Our study provides new insights into the effects of psychological stress on psoriasis pathogenesis and the mechanisms involved, which provides clues for development of therapeutics or biomarkers.


Assuntos
Aminoquinolinas , Psoríase , Camundongos , Humanos , Animais , Imiquimode/toxicidade , Aminoquinolinas/toxicidade , Camundongos Endogâmicos BALB C , Psoríase/induzido quimicamente , Psoríase/genética , Análise de Sequência de RNA , Modelos Animais de Doenças , Pele
7.
Microbiol Spectr ; 10(6): e0395222, 2022 12 21.
Artigo em Inglês | MEDLINE | ID: mdl-36350125

RESUMO

Alternative antimicrobial therapies are urgently required for the multidrug-resistant bacterial pathogen Neisseria gonorrhoeae, for which currently ceftriaxone is the only remaining recommended first-line therapy. Repurposing of drugs that are approved for other clinical applications offers an efficient approach for development of alternative antimicrobial therapies. Auranofin, cannabidivarin, and tolfenamic acid were recently identified to display antimicrobial activity against N. gonorrhoeae. Here, we investigated their activity against a collection of 575 multidrug-resistant clinical isolates. All three compounds displayed consistent antimicrobial activity against all isolates, including against strains associated with the high-level ceftriaxone-resistant FC428 clone, with both the mode and MIC90 for auranofin of 0.5 mg/L, while both the mode and MIC90 for cannabidivarin and tolfenamic acid were 8 mg/L. Correlations between MICs of ceftriaxone and auranofin, cannabidivarin or tolfenamic acid were low, indicating that development of cross-resistance is unlikely. Furthermore, antimicrobial synergy analysis between ceftriaxone and auranofin, cannabidivarin, or tolfenamic acid by determination of the fractional inhibitory concentration index (FICI) resulted in an interpretation of indifference. Finally, time-kill analyses showed that all three compounds are bactericidal against both the N. gonorrhoeae ATCC 49226 reference strain and an FC428-associated clinical isolate, with particularly cannabidivarin displaying rapid bactericidal activity. Overall, auranofin, cannabidivarin, and tolfenamic acid displayed consistent antimicrobial activity against multidrug-resistant N. gonorrhoeae, warranting further exploration of their suitability as alternative antimicrobials for treatment of gonococcal infections. IMPORTANCE Neisseria gonorrhoeae is a major public health concern because of the high incidence of gonorrhea and the increasingly limited options for antimicrobial therapy. Strains associated with the FC428 clone are a particular concern because they have shown global dissemination and they display high-level resistance against the currently recommended ceftriaxone therapy. Therefore, development of alternative antimicrobial therapies is urgently required to ensure treatment of gonorrhea remains available in the future. Repurposing of clinically approved drugs could be a rapid approach for the development of such alternative antimicrobials. In this study, we showed that repurposing of auranofin, cannabidivarin, and tolfenamic acid for antimicrobial therapy of gonorrhea deserves further clinical explorations because these compounds displayed consistent antimicrobial activity against a large collection of contemporary multidrug-resistant gonococcal isolates that included strains associated with the FC428 clone.


Assuntos
Anti-Infecciosos , Gonorreia , Humanos , Neisseria gonorrhoeae , Gonorreia/epidemiologia , Ceftriaxona/farmacologia , Auranofina/farmacologia , Auranofina/uso terapêutico , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Anti-Infecciosos/farmacologia , Testes de Sensibilidade Microbiana , Farmacorresistência Bacteriana
8.
BMC Microbiol ; 22(1): 176, 2022 07 08.
Artigo em Inglês | MEDLINE | ID: mdl-35804301

RESUMO

BACKGROUND: Staphylococcus aureus is a leading cause for morbidity and mortality associated with skin and burn wound infections. Therapeutic options for methicillin-resistant S. aureus (MRSA) have dwindled and therefore alternative treatments are urgently needed. In this study, the immuno-stimulating and anti-MRSA effects of cyclic di-guanosine monophosphate (c-di-GMP), a uniquely bacterial second messenger and immuno-modulator, were investigated in HaCaT human epidermal keratinocytes and a murine skin wound infection model. RESULTS: Stimulation of HaCaT cells with 125 µM c-di-GMP for 12 h prior to MRSA challenge resulted in a 20-fold reduction in bacterial colonization compared with untreated control cells, which was not the result of a direct c-di-GMP toxic effect, since bacterial viability was not affected by this dose in the absence of HaCaT cells. C-di-GMP-stimulated or MRSA-challenged HaCaT cells displayed enhanced secretion of the antimicrobial peptides human ß-defensin 1 (hBD-1), hBD-2, hBD-3 and LL-37, but for hBD1 and LL-37 the responses were additive in a c-di-GMP-dose-dependent manner. Secretion of the chemokines CXCL1 and CXCL8 was also elevated after stimulation of HaCaT cells with lower c-di-GMP doses and peaked at a dose of 5 µM. Finally, pre-treatment of mice with a 200 nmol dose of c-di-GMP 24 h before a challenge with MRSA in skin wound infection model resulted in a major reduction (up to 1,100-fold by day 2) in bacterial CFU counts recovered from challenged skin tissue sections compared PBS-treated control animals. Tissue sections displayed inflammatory cell infiltration and enhanced neutrophil influx in the c-di-GMP pre-treated animals, which might account for the reduced ability of MRSA to colonize c-di-GMP pre-treated mice. CONCLUSIONS: These results demonstrate that c-di-GMP is a potent immuno-modulator that can stimulate anti-MRSA immune responses in vivo and might therefore be a suitable alternative prophylactic or therapeutic agent for MRSA skin or burn wound infections.


Assuntos
Adjuvantes Imunológicos , GMP Cíclico/análogos & derivados , Imunidade Inata , Staphylococcus aureus Resistente à Meticilina , Infecções Cutâneas Estafilocócicas , Adjuvantes Imunológicos/farmacologia , Adjuvantes Imunológicos/uso terapêutico , Animais , Queimaduras/complicações , GMP Cíclico/farmacologia , GMP Cíclico/uso terapêutico , Modelos Animais de Doenças , Humanos , Imunidade Inata/efeitos dos fármacos , Queratinócitos/efeitos dos fármacos , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Camundongos , Infecções Cutâneas Estafilocócicas/tratamento farmacológico
9.
J Antimicrob Chemother ; 77(9): 2461-2469, 2022 08 25.
Artigo em Inglês | MEDLINE | ID: mdl-35762496

RESUMO

OBJECTIVES: Ceftriaxone therapy for gonorrhoea has become under increasing pressure due to waning susceptibility levels and emergence of high-level resistant strains such as the FC428 clone. Moenomycin was recently identified to display potent anti-gonococcal activity against some reference strains. Therefore, the aim of this study was to investigate moenomycin in vitro and in vivo antimicrobial activity. METHODS: Moenomycin in vitro antimicrobial activity was investigated against 575 clinical isolates, including strains associated with the FC428 clone, using the agar dilution method. Moenomycin in vivo activity was investigated in a mouse vaginal tract gonococcal infection model. RESULTS: The moenomycin MIC range for the strain collection was 0.004-0.06 mg/L, with a MIC50 of 0.016 mg/L and a MIC90 of 0.03 mg/L. The correlation between moenomycin and ceftriaxone susceptibility levels was poor (R = 0.13), while the fractional inhibitory concentration index (FICI) resulted in indifference for all tested strains. Therefore, development of cross-resistance between moenomycin and ceftriaxone is unlikely for N. gonorrhoeae. Determination of the moenomycin mode of activity against N. gonorrhoeae by time-kill assays showed that moenomycin is bactericidal, with over 104-fold inactivation observed after 4 h exposure. Finally, an intramuscular moenomycin dose of 10 mg/kg given on 2 consecutive days was able to clear a gonococcal infection in a mouse vaginal tract infection model within 1-3 days after the second dose, which was significantly faster than for mice treated with the vehicle control (P < 0.0001). CONCLUSIONS: Moenomycin displays potent in vitro and in vivo antimicrobial activity against N. gonorrhoeae, warranting further exploration as alternative therapy.


Assuntos
Bambermicinas , Gonorreia , Animais , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Ceftriaxona/farmacologia , Ceftriaxona/uso terapêutico , Farmacorresistência Bacteriana , Feminino , Gonorreia/tratamento farmacológico , Camundongos , Testes de Sensibilidade Microbiana , Neisseria gonorrhoeae
10.
Oxid Med Cell Longev ; 2022: 1863098, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35368866

RESUMO

Consistent high-risk human papillomavirus (HPV) infection leads to various malignant cancers. Autophagy can promote cancer progression by helping cancer cells survive under stress or induce oncogenic effects when mutations or abnormalities occur. Mitogen activated protein kinases (MAPKs) can transduce various external or intrinsic stimuli into cellular responses, including autophagy, and dual-specificity phosphates (DUSPs) contribute to the direct regulation of MAPK activities. Previously, we showed that expression of DUSP5 was repressed in HPV16 E7-expressing normal human epidermal keratinocytes (NHEKs). Here we show that clinical HPV16 E7-positive precancerous and cancerous tissues also demonstrate low DUSP5 levels compared with control tissues, indicating that the inverse correlation between HPV16 E7 and DUSP5 is clinically relevant. We furthermore investigated the autophagy response in both DUSP5-deficient and HPV16 E7-expressing NHEKs. Confocal microscopy and Western analysis showed induction of LC3-II levels, autophagosome formation and autophagy fluxes in DUSP5-deficient NHEKs. Furthermore, Western analysis demonstrated specific induction of phosphorylated ERK in DUSP5-deficient and HPV16 E7-expressing NHEKs, indicating that HPV16 E7-mediated repression of DUSP5 results in induced MAPK/ERK signaling. Finally, phosphorylated mTOR and ULK (S757) were reduced in DUSP5-deficient NHEKs, while phosphorylated ULK (S555) and AMPK were increased, thereby inducing canonical autophagy through the mTOR and AMPK pathways. In conclusion, our results demonstrate that HPV16 E7 expression reduces DUSP5 levels, which in turn results in active MAPK/ERK signaling and induction of canonical autophagy through mTOR and MAPK regulation. Given its demonstrated inverse correlation with clinical cancerous tissues, DUSP5 may serve as a potential therapeutic target for cervical cancer.


Assuntos
Alphapapillomavirus , Neoplasias do Colo do Útero , Alphapapillomavirus/metabolismo , Autofagia , Fosfatases de Especificidade Dupla/genética , Fosfatases de Especificidade Dupla/metabolismo , Feminino , Humanos , Queratinócitos/metabolismo , Neoplasias do Colo do Útero/genética
11.
ACS Cent Sci ; 8(3): 322-331, 2022 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-35350606

RESUMO

The identification of an alternative chemical space in order to address the global challenge posed by emerging antimicrobial resistance is very much needed for the discovery of novel antimicrobial lead compounds. Boron clusters are currently being explored in drug discovery due to their unique steric and electronic properties. However, the challenges associated with the synthesis and derivatization techniques of these compounds have limited their utility in the rapid construction of a library of molecules for screening against various biological targets as an alternative molecular platform. Herein, we report a transition-metal-catalyzed regioselective direct B-H alkylation-annulation of the closo-dodecaborate anion with natural products such as menthol and camphor as the directing groups. This method allowed the rapid construction of a library of 1,2,3-trisubstituted clusters, which were evaluated in terms of their antibacterial activity against WHO priority pathogens. Several of the synthesized dodecaborate derivatives displayed medium- to high-level bactericidal activity against Gram-positive and Gram-negative bacteria.

12.
BMC Infect Dis ; 22(1): 169, 2022 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-35189827

RESUMO

BACKGROUND: Mycoplasma hominis is typically associated with a urogenital tract infection, while its association with bacteremia and pneumonia is rare and therefore easily overlooked. Here we report a M. hominis bloodstream infection and pneumonia in a surgical patient. CASE PRESENTATION: A 56-year-old male with symptoms of pneumonia underwent microsurgery and decompressive craniectomy after a left basal ganglia hemorrhage. The patient recovered well from surgery, but pulmonary symptoms progressively worsened, with antimicrobial therapies seemingly ineffective. Culturing of bilateral blood samples resulted in pin-point-sized colonies on blood agar plates, which were subsequently identified as M. hominis by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. Furthermore, sequencing of bronchoalveolar lavage samples also identified M. hominis as the main pathogen responsible for the pulmonary symptoms. The M. hominis strain was ciprofloxacin resistant, but susceptible to doxycycline and moxifloxacin. Doxycycline and moxifloxacin were subsequently used in a successful combination therapy that finally alleviated the patient's fever and resulted in absorption of pleural effusion. At 1-month follow-up, following complaints of dysuria, a prostate abscess containing M. hominis was detected as the likely primary source of infection. The abscess was successfully drained and treated with doxycycline. CONCLUSIONS: Mycoplasma hominis should be considered as a source of bloodstream infections and pneumonia, particularly when the response to standard antimicrobial therapy is limited. In this case, effective antimicrobial therapy was only commenced after identification of M. hominis and antimicrobial susceptibility testing.


Assuntos
Infecções por Mycoplasma , Neurocirurgia , Pneumonia , Sepse , Humanos , Masculino , Pessoa de Meia-Idade , Infecções por Mycoplasma/diagnóstico , Infecções por Mycoplasma/tratamento farmacológico , Infecções por Mycoplasma/etiologia , Mycoplasma hominis , Pneumonia/complicações , Sepse/complicações
13.
J Antimicrob Chemother ; 76(4): 936-939, 2021 03 12.
Artigo em Inglês | MEDLINE | ID: mdl-33406237

RESUMO

OBJECTIVES: Ceftriaxone is currently the last-remaining empirical antimicrobial therapy for treatment of gonorrhoea. However, the high-level ceftriaxone-resistant gonococcal FC428 clone has shown transmission in China in recent years. Therefore, the aim of this study was to analyse ceftriaxone resistance among a collection of recent clinical isolates, with a specific focus on prevalence of the FC428 clone. METHODS: A total of 70 consecutive gonococcal isolates were collected between May and October 2019 from a single hospital in Hangzhou, China, and analysed for antimicrobial susceptibility by the agar dilution method. STs were determined by PCR and sequences and isolates related to the FC428 clone were further characterized by WGS and phylogenetic analysis. RESULTS: Ceftriaxone resistance (MIC >0.125 mg/L) was observed in 21 (30%) isolates, while 14 (20%) isolates displayed a ceftriaxone MIC of 0.125 mg/L. Importantly, seven (10%) isolates were related to the gonococcal FC428 clone based on the presence of mosaic penA allele 60.001, displaying identical or closely related STs, and phylogenetic analysis after WGS. These seven isolates displayed high-level ceftriaxone resistance (MIC = 1 mg/L) and all associated gonorrhoea cases resulted in treatment failure because oral cephalosporins were initially prescribed. Subsequent re-treatment with a higher dose (2 g) of IV ceftriaxone appeared to be successful because all patients returning for test-of-cure became culture-negative. CONCLUSIONS: Here, we report a high percentage of the internationally spreading gonococcal FC428 clone among clinical isolates from a single hospital in Hangzhou, China. A high dose of ceftriaxone is currently the only recommended and effective therapy.


Assuntos
Gonorreia , Neisseria gonorrhoeae , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Ceftriaxona/farmacologia , China/epidemiologia , Células Clonais , Farmacorresistência Bacteriana , Gonorreia/tratamento farmacológico , Gonorreia/epidemiologia , Hospitais , Humanos , Testes de Sensibilidade Microbiana , Neisseria gonorrhoeae/genética , Filogenia
14.
J Infect Dis ; 223(4): 721-732, 2021 02 24.
Artigo em Inglês | MEDLINE | ID: mdl-32644146

RESUMO

BACKGROUND: Base excision repair (BER), consisting mostly of lesion-specific DNA glycosylases and apurinic/apyrimidinic (AP) endonucleases, is one of the most important DNA repair mechanisms for repair of single nucleobase lesions generated by reactive oxygen and nitrogen species as part of an immune response against bacterial infections. However, few studies have addressed the contribution of BER to bacterial virulence and Listeria monocytogenes BER has thus far remained completely uncharacterized. METHODS: Analysis of the L. monocytogenes EGDe genome identified 7 DNA glycosylases (MutM, MutY, Nth, Tag, Mpg, Ung, and Ung2) and 2 apurinic/apyrimidinic endonucleases (Xth and Nfo) as part of BER. Markerless in-frame deletion mutants were generated for all 9 genes, and mutants were tested for DNA damage survival, mutagenesis, and the ability to colonize a mouse model of infection. RESULTS: Distinct lesion-specific phenotypes were identified for all deletion mutants. Importantly, the Δnth, ΔmutY, and Δnfo mutants were significantly attenuated for virulence in the mouse model and showed much lower colonization of the liver and spleen or were unable to compete with the wild-type strain during in vivo competition assays. CONCLUSIONS: Our results highlight the importance of BER for L. monocytogenes virulence and survival of DNA-damaging insults during host colonization.


Assuntos
Reparo do DNA , DNA Bacteriano/metabolismo , Listeria monocytogenes/genética , Listeria monocytogenes/patogenicidade , Listeriose/microbiologia , Macrófagos/microbiologia , Animais , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Dano ao DNA , DNA Glicosilases/genética , DNA Glicosilases/metabolismo , Reparo do DNA/genética , DNA Bacteriano/genética , DNA Liase (Sítios Apurínicos ou Apirimidínicos)/genética , DNA Liase (Sítios Apurínicos ou Apirimidínicos)/metabolismo , Feminino , Genes Bacterianos , Humanos , Listeria monocytogenes/crescimento & desenvolvimento , Listeria monocytogenes/metabolismo , Fígado/microbiologia , Camundongos , Camundongos Endogâmicos BALB C , Deleção de Sequência , Baço/microbiologia , Células THP-1
15.
J Infect Dis ; 224(1): 141-150, 2021 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-33170275

RESUMO

Neisseria gonorrhoeae is a bacterial pathogen that colonizes mucosal epithelia that are rich in antimicrobial molecules such as long-chain fatty acids. Here we studied the mechanisms involved in palmitic acid resistance and their impact on in vivo biological fitness in a murine genital tract infection model. A stable palmitic acid-resistant derivative was obtained by serial passage with incremental palmitic acid concentrations. This derivative outcompeted its parent strain for colonization and survival in the murine infection model. Subsequent whole-genome sequencing resulted in the identification of the 3 resistance-related SNPs ihfAC5T, fadDC772T, and farAG-52T (promoter) that were verified for resistance against palmitic acid. Subsequent characterization of the associated resistance determinants showed that ihfAC5T and farAG-52T induced gene expression of the FarAB efflux pump, whereas fadDC772T increased the maximum enzyme activity of the FadD long-chain fatty acid-coenzyme A ligase. Our results highlight the mechanisms involved in gonococcal adaptation to the murine host environment.


Assuntos
Proteínas de Bactérias/fisiologia , Coenzima A Ligases/genética , Gonorreia/etiologia , Mutação , Ácido Palmítico/farmacologia , Infecções do Sistema Genital/etiologia , Animais , Modelos Animais de Doenças , Feminino , Células HeLa , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Neisseria gonorrhoeae/efeitos dos fármacos , Doenças Vaginais/etiologia
16.
Aging (Albany NY) ; 12(22): 23017-23028, 2020 11 16.
Artigo em Inglês | MEDLINE | ID: mdl-33197887

RESUMO

Human papillomavirus type 11 (HPV11) is one of the main causes of condyloma acuminatum, a widespread sexually transmitted disease. During infection of its primary target cell, keratinocytes, it is likely to encounter the autophagy pathway, which is an intracellular maintenance process that is also able to target invading pathogens. It is currently unknown whether HPV11 is targeted by autophagy or whether it is able to escape autophagy-mediated killing. Here, we investigated the autophagy response during HPV11 pseudovirion (PsV) entry in human keratinocytes. Transmission electron microscopy showed that intracellular PsVs were sequestered in lumen of double-membrane autophagosomes that subsequently appeared to fuse with lysosomes, while confocal microscopy showed induction LC3 puncta, the hallmark of induced autophagy activity. Furthermore, quantitative infection assays showed that high autophagy activity resulted in reduced HPV11 PsV infectivity. Therefore, the autophagy pathway seemed to actively target invading HPV11 PsVs for destruction in the autolysosome. Western analysis on the phosphorylation state of autophagy regulators and upstream pathways indicated that autophagy was activated through interplay between Erk and Akt signaling. In conclusion, autophagy functions as a cellular protection mechanism against intracellular HPV11 and therefore therapies that stimulate autophagy may prevent recurrent condyloma acuminatum by helping eliminate latent HPV11 infections.


Assuntos
Autofagia , Papillomavirus Humano 11/patogenicidade , Queratinócitos/virologia , Infecções por Papillomavirus/virologia , Vírion/patogenicidade , Internalização do Vírus , Proteínas Relacionadas à Autofagia/metabolismo , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Células HaCaT , Interações Hospedeiro-Patógeno , Papillomavirus Humano 11/ultraestrutura , Humanos , Queratinócitos/metabolismo , Queratinócitos/ultraestrutura , Infecções por Papillomavirus/metabolismo , Infecções por Papillomavirus/patologia , Fosforilação , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais , Serina-Treonina Quinases TOR/metabolismo , Vírion/ultraestrutura
17.
PLoS One ; 15(9): e0238710, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32911519

RESUMO

OBJECTIVES: China has a high burden of gonorrhea, but an imbalanced male-to-female (M/F) ratio of reported cases. Therefore, the prevalence of gonorrhea in China may be underestimated due to inadequate testing of potentially infected females. The objective of this study is to investigate the cause of this imbalanced M/F ratio and develop strategies to enhance gonorrhea surveillance, particularly among females. METHODS: The national center for STD control (NCSTDC) of China CDC collected data in Zhongshan city over the year 2018 from the National Notifiable Disease Report System (NNDRS) and the Hospital and Laboratory Information Systems (HIS and LIS) that obtains information from 24 hospitals. RESULTS: Analysis of 1,542 reported cases of gonorrhea and the case distribution among different hospitals showed that most of the female cases (80.31%) were reported by gynecological clinics. The M/F ratio of reported cases varied between different hospitals and was dependent on the intensity of testing of females by their gynecological clinics. CONCLUSIONS: This study showed a significant correlation between M/F ratios and the relative contribution of female gonorrhea testing, especially in gynecology clinics. Enhancing gonorrhea testing among females should be advocated to improve surveillance in China.


Assuntos
Gonorreia/epidemiologia , Ginecologia , Vigilância da População , China/epidemiologia , Feminino , Gonorreia/diagnóstico , Hospitais , Humanos , Masculino , Projetos Piloto
18.
Front Genet ; 11: 819, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32849815

RESUMO

High-risk human papillomavirus (HPV) infections are the predominant cause of cervical cancer and its early gene E7 plays an important role in cellular proliferation and cell-cycle progression. While tremendous progress has been made in exploring the molecular mechanisms in late tumorigenesis, many pathways showing how HPV deregulates host gene expression in early inapparent infections and early tumorigenesis still remain undefined. Digital RNA sequencing was performed and a total of 195 differentially expressed genes were identified between the HPV16 E7-transfected NHEKs and control cells (p < 0.05, fold-change > 2). GO enrichment showed that HPV16 E7 primarily affected processes involved in anti-viral and immune responses, while KEGG pathway analysis showed enrichment of gene clusters of associated with HPV infection and MAPK signaling. Of the differentially expressed genes, IFI6, SLC39A9 and ZNF185 showed a strong correlation with tumor progression and patient survival in the OncoLnc database while roles for AKAP12 and DUSP5 in carcinogenesis and poor prognosis have previously been established for other cancer types. Our study identified several novel HPV16 E7-regulated candidate genes with putative functions in tumorigenesis, thus providing new insights into HPV persistence in keratinocytes and early onset of tumorigenesis.

19.
Emerg Microbes Infect ; 9(1): 1219-1229, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32438866

RESUMO

Global dissemination of the Neisseria gonorrhoeae ceftriaxone-resistant FC428 clone jeopardizes the currently recommended ceftriaxone-based first-line therapies. Ceftriaxone resistance in the FC428 clone has been associated with the presence of its mosaic penA allele 60.001. Here we investigated the contribution penA allele 60.001 to ceftriaxone resistance and its impact on biological fitness. Gonococcal isolates expressing penA allele 60.001 and mosaic penA allele 10.001, which is widespread in the Asia-Pacific region and associated with reduced susceptibility to ceftriaxone and cefixime, were genetic engineered to exchange their penA alleles. Subsequent antimicrobial susceptibility analyses showed that mutants containing penA 60.001 displayed 8- to 16-fold higher ceftriaxone and cefixime minimal inhibitory concentrations (MICs) compared with otherwise isogenic mutants containing penA 10.001. Further analysis of biological fitness showed that in vitro liquid growth of single strains and in the competition was identical between the isogenic penA allele exchange mutants. However, in the presence of high concentrations of palmitic acid or lithocholic acid, the penA 60.001-containing mutants grew better than the isogenic penA 10.001-containing mutants when grown as single strains. In contrast, the penA 10.001 mutants outcompeted the penA 60.001 mutants when grown in competition at slightly lower palmitic acid or lithocholic acid concentrations. Finally, the penA 60.001 mutants were outcompeted by their penA 10.001 counterparts for in vivo colonization and survival in a mouse vaginal tract infection model. In conclusion, penA allele 60.001 is essential for ceftriaxone resistance of the FC428 clone, while its impact on biological fitness is dependent on the specific growth conditions.


Assuntos
Antibacterianos/farmacologia , Farmacorresistência Bacteriana , Gonorreia/microbiologia , Mutação , Neisseria gonorrhoeae/crescimento & desenvolvimento , Alelos , Animais , Ceftriaxona/farmacologia , Modelos Animais de Doenças , Feminino , Aptidão Genética , Ácido Litocólico/farmacologia , Camundongos , Testes de Sensibilidade Microbiana , Neisseria gonorrhoeae/efeitos dos fármacos , Neisseria gonorrhoeae/genética , Neisseria gonorrhoeae/isolamento & purificação , Ácido Palmítico/farmacologia
20.
J Antimicrob Chemother ; 75(9): 2499-2502, 2020 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-32473014

RESUMO

BACKGROUND: Ceftriaxone resistance in Neisseria gonorrhoeae has become an imminent threat to effective control of gonorrhoea globally. In recent years, the ceftriaxone-resistant FC428 clone has shown international dissemination. After our first report of the FC428 clone in China in 2016, we now describe another six cases of FC428-related ceftriaxone-resistant N. gonorrhoeae isolates from 2017 and 2018. OBJECTIVES: To identify the phenotypic and molecular characteristics of newly reported ceftriaxone-resistant isolates in China and to investigate the relationship between these isolates and FC428 clones reported globally. METHODS: Antimicrobial susceptibility to ceftriaxone, cefixime, azithromycin, spectinomycin, penicillin, ciprofloxacin and tetracycline was determined by the agar dilution method. N. gonorrhoeae multi-antigen sequence typing (NG-MAST), MLST and N. gonorrhoeae sequence typing for antimicrobial resistance (NG-STAR) were performed for genotyping and SNPs extracted from whole-genome sequences were used for phylogenetic analysis. RESULTS: All isolates were resistant to ceftriaxone, cefixime, penicillin, tetracycline and ciprofloxacin, but were susceptible to azithromycin and spectinomycin. NG-MAST, MLST and NG-STAR genotyping showed that all isolates shared identical or similar STs (<10 bp difference) to FC428 (NG-MAST ST3435, MLST ST1903, NG-STAR ST233) and contained the same mosaic penA allele 60.001. Phylogenetic analysis showed the Chinese isolates spreading in the whole phylogenetic tree and fully mixed with other international isolates. Half of the Chinese isolates were more closely related (<100 SNPs) to Japanese isolates than other international isolates. CONCLUSIONS: The newly reported cases in China were related to the internationally spreading FC428 clone. These isolates might have played a central role in international transmission of the FC428 clone. High ceftriaxone doses (1-2 g) still provide effective therapy.


Assuntos
Gonorreia , Neisseria gonorrhoeae , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Ceftriaxona/farmacologia , China/epidemiologia , Células Clonais , Farmacorresistência Bacteriana , Gonorreia/tratamento farmacológico , Gonorreia/epidemiologia , Humanos , Testes de Sensibilidade Microbiana , Tipagem de Sequências Multilocus , Neisseria gonorrhoeae/genética , Filogenia
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