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1.
Zhonghua Jie He He Hu Xi Za Zhi ; 43(12): 1061-1065, 2020 Dec 12.
Artigo em Chinês | MEDLINE | ID: mdl-33333640

RESUMO

Objective: To test the in vitro antibacterial activity of nemonoxacin against clinically isolates of Mycobacterium tuberculosis complex(MTBC), Mycobacterium intracellulare(MI) and Mycobacterium abscessus(MA). Methods: Totally 128, 80 and 50 isolates of MTBC, M.intracellulare and M.abscessus were tested, respectively. The minimum inhibitory concentrations (MICs) of nemonoxacin and levofloxacin against the strains of the three most frequently isolated mycobacterium species were measured by double dilution method with micro-well plate. Results: The MICs of 104(81.2%) strains of MTBC isolates against levofloxacin were ≤ 1 µg/ml. Whereas 112 (87.5%) strains of MTBC isolates had MICs against nemonoxacin than>1 µg/ml, furthermore, the MICs of 88(68.8%)strains of MTBC isolates against nemonoxacin were≥4 µg/ml. The median MIC of M. intracellulare isolates against levofloxacin and nenofloxacin were 16 and 32 µg/ml, separately, while were 16 µg/ml and 8 µg/ml for M. abscessus, respectively. The ratios of nemonoxacin MIC/levofloxacin MIC of M. abscessus were between 0.125-1.000. Conclusions: Nemonoxacin presented weaker inhibitory activity than levofloxacin against M. tuberculosis, whereas it had better activity than levofloxacin against M. abscessus.


Assuntos
Antibacterianos/farmacologia , Mycobacterium abscessus/efeitos dos fármacos , Complexo Mycobacterium avium/efeitos dos fármacos , Mycobacterium tuberculosis/efeitos dos fármacos , Quinolonas/farmacologia , Tuberculose/tratamento farmacológico , Antibacterianos/uso terapêutico , Humanos , Testes de Sensibilidade Microbiana , Mycobacterium abscessus/isolamento & purificação , Complexo Mycobacterium avium/isolamento & purificação , Mycobacterium tuberculosis/isolamento & purificação , Quinolonas/uso terapêutico
2.
PLoS One ; 15(12): e0243392, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33370295

RESUMO

Leishmaniasis is a neglected, parasitic tropical disease caused by an intracellular protozoan from the genus Leishmania. Quinoline alkaloids, secondary metabolites found in plants from the Rutaceae family, have antiparasitic activity against Leishmania sp. N-methyl-8-methoxyflindersin (1), isolated from the leaves of Raputia heptaphylla and also known as 7-methoxy-2,2-dimethyl-2H,5H,6H-pyran[3,2-c]quinolin-5-one, shows antiparasitic activity against Leishmania promastigotes and amastigotes. This study used in silico tools to identify synthetic quinoline alkaloids having structure similar to that of compound 1 and then tested these quinoline alkaloids for their in vitro antiparasitic activity against Leishmania (Viannia) panamensis, in vivo therapeutic response in hamsters suffering from experimental cutaneous leishmaniasis (CL), and ex vivo immunomodulatory potential in healthy donors' human peripheral blood (monocyte)-derived macrophages (hMDMs). Compounds 1 (natural), 2 (synthetic), and 8 (synthetic) were effective against intracellular promastigotes (9.9, 3.4, and 1.6 µg/mL medial effective concentration [EC50], respectively) and amastigotes (5.07, 7.94, and 1.91 µg/mL EC50, respectively). Compound 1 increased nitric oxide production in infected hMDMs and triggered necrosis-related ultrastructural alterations in intracellular amastigotes, while compound 2 stimulated oxidative breakdown in hMDMs and caused ultrastructural alterations in the parasite 4 h posttreatment, and compound 8 failed to induce macrophage modulation but selectively induced apoptosis of infected hMDMs and alterations in the intracellular parasite ultrastructure. In addition, synthetic compounds 2 and 8 improved the health of hamsters suffering from experimental CL, without evidence of treatment-associated adverse toxic effects. Therefore, synthetic compounds 2 and 8 are potential therapeutic candidates for topical treatment of CL.


Assuntos
Antiprotozoários/farmacologia , Compostos Heterocíclicos com 3 Anéis/farmacologia , Leishmania guyanensis/efeitos dos fármacos , Leishmaniose Cutânea/tratamento farmacológico , Alcaloides/farmacologia , Animais , Antiprotozoários/química , Cricetinae , Modelos Animais de Doenças , Compostos Heterocíclicos com 3 Anéis/química , Humanos , Leishmania guyanensis/patogenicidade , Leishmaniose Cutânea/parasitologia , Leishmaniose Cutânea/patologia , Macrófagos/efeitos dos fármacos , Macrófagos/parasitologia , Camundongos , Óxido Nítrico/genética , Folhas de Planta/química , Quinolinas/química , Quinolonas/farmacologia , Rutaceae/química
3.
F1000Res ; 9: 1166, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33204411

RESUMO

Background: The coronavirus disease 2019 (COVID-19) pandemic, caused by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), took more lives than combined epidemics of SARS, MERS, H1N1, and Ebola. Currently, the prevention and control of spread are the goals in COVID-19 management as there are no specific drugs to cure or vaccines available for prevention. Hence, the drug repurposing was explored by many research groups, and many target proteins have been examined. The major protease (M pro), and RNA-dependent RNA polymerase (RdRp) are two target proteins in SARS-CoV-2 that have been validated and extensively studied for drug development in COVID-19. The RdRp shares a high degree of homology between those of two previously known coronaviruses, SARS-CoV and MERS-CoV. Methods: In this study, the FDA approved library of drugs were docked against the active site of RdRp using Schrodinger's computer-aided drug discovery tools for in silico drug-repurposing. Results: We have shortlisted 14 drugs from the Standard Precision docking and interaction-wise study of drug-binding with the active site on the enzyme. These drugs are antibiotics, NSAIDs, hypolipidemic, coagulant, thrombolytic, and anti-allergics. In molecular dynamics simulations, pitavastatin, ridogrel and rosoxacin displayed superior binding with the active site through ARG555 and divalent magnesium. Conclusion: Pitavastatin, ridogrel and rosoxacin can be further optimized in preclinical and clinical studies to determine their possible role in COVID-19 treatment.


Assuntos
Antivirais , Infecções por Coronavirus/tratamento farmacológico , Reposicionamento de Medicamentos , Pneumonia Viral/tratamento farmacológico , /antagonistas & inibidores , Antivirais/farmacologia , Betacoronavirus/efeitos dos fármacos , Betacoronavirus/enzimologia , Domínio Catalítico , Humanos , Simulação de Acoplamento Molecular , Pandemias , Ácidos Pentanoicos/farmacologia , Piridinas/farmacologia , Quinolinas/farmacologia , Quinolonas/farmacologia
4.
PLoS Pathog ; 16(9): e1008867, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32925969

RESUMO

Surface attachment, an early step in the colonization of multiple host environments, activates the virulence of the human pathogen P. aeruginosa. However, the downstream toxins that mediate surface-dependent P. aeruginosa virulence remain unclear, as do the signaling pathways that lead to their activation. Here, we demonstrate that alkyl-quinolone (AQ) secondary metabolites are rapidly induced upon surface association and act directly on host cells to cause cytotoxicity. Surface-induced AQ cytotoxicity is independent of other AQ functions like quorum sensing or PQS-specific activities like iron sequestration. We further show that packaging of AQs in outer-membrane vesicles (OMVs) increases their cytotoxicity to host cells but not their ability to stimulate downstream quorum sensing pathways in bacteria. OMVs lacking AQs are significantly less cytotoxic, suggesting these molecules play a role in OMV cytotoxicity, in addition to their previously characterized role in OMV biogenesis. AQ reporters also enabled us to dissect the signal transduction pathways downstream of the two known regulators of surface-dependent virulence, the quorum sensing receptor, LasR, and the putative mechanosensor, PilY1. Specifically, we show that PilY1 regulates surface-induced AQ production by repressing the AlgR-AlgZ two-component system. AlgR then induces RhlR, which can induce the AQ biosynthesis operon under specific conditions. These findings collectively suggest that the induction of AQs upon surface association is both necessary and sufficient to explain surface-induced P. aeruginosa virulence.


Assuntos
Proteínas de Bactérias/metabolismo , Infecções por Pseudomonas/metabolismo , Pseudomonas aeruginosa , Quinolonas/farmacologia , Percepção de Quorum/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Fatores de Virulência/metabolismo , Células A549 , Animais , Humanos , Camundongos , Infecções por Pseudomonas/patologia , Pseudomonas aeruginosa/metabolismo , Pseudomonas aeruginosa/patogenicidade
5.
Int J Food Microbiol ; 335: 108859, 2020 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-32947147

RESUMO

In this study, 205 Salmonella enterica serovar Corvallis strains were obtained from humans and foods from Guangdong, Guangxi, and Shanghai in China from 2009 to 2017 to assess drug resistance and molecular epidemiology. These isolates displayed high rates of resistance to sulfisoxazole (94.15%) and tetracycline (77.56%). Surprisingly, the rate of resistance to ciprofloxacin reached 21.46%. Moreover, 63.9% of the strains displayed multidrug resistance. Detection of quinolone genes showed that 97.56% of the strains had single mutations (T57S) in parC. The plasmid-mediated quinolone resistance (PMQR) genes qnrS, aac(6')-Ib-cr, and qnrB, were also detected. The extended spectrum ß-lactamase (ESBLS) gene that was most common among the isolates was blaTEM-1 (18.05%). These S. Corvallis isolates are the first to date, that have been reported to possess blaCTX-M-55 or blaNDM-5. Additionally, 95.61% of isolates were biofilm producers. The streptomycin resistance rate was higher in strong biofilm producers (87.50%) than in moderate (37.93%) and weak (26.49%) biofilm producers. Pulsed-field gel electrophoresis (PFGE) showed that some strains from different sources had the same genotype. These isolates may be transmitted to humans through food and therefore the monitoring of these isolates should be strengthened in China.


Assuntos
Farmacorresistência Bacteriana Múltipla/genética , Quinolonas/farmacologia , Salmonella enterica/efeitos dos fármacos , Salmonella enterica/genética , beta-Lactamases/genética , Animais , Antibacterianos/farmacologia , Biofilmes/crescimento & desenvolvimento , Galinhas/microbiologia , China , Eletroforese em Gel de Campo Pulsado , Microbiologia de Alimentos , Humanos , Testes de Sensibilidade Microbiana , Plasmídeos/genética , Prevalência , Salmonella enterica/isolamento & purificação , Sorogrupo
6.
Cell Prolif ; 53(10): e12901, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32960500

RESUMO

OBJECTIVES: To assess the expression, prognostic value, and functionality of T-lymphokine-activated killer (T-LAK) cell-originated protein kinase (TOPK) in chordoma pathogenesis. MATERIALS AND METHODS: TOPK expression in chordoma was assessed via immunohistochemical staining of a tissue microarray (TMA) and correlated with patient clinicopathology. TOPK expression in chordoma cell lines and fresh patient tissues was then evaluated by Western blot. TOPK small interfering RNA (siRNA) and the specific inhibitor OTS514 were applied to determine the roles of TOPK in chordoma pathogenicity. The effect of TOPK expression on chordoma cell clonogenicity was also investigated using clonogenic assays. A 3D cell culture model was utilized to mimic in vivo environment to validate the effect of TOPK inhibition on chordoma cells. RESULTS: TOPK was highly expressed in 78.2% of the chordoma specimens in the TMA and all chordoma cell lines. High TOPK expression significantly correlated with metastasis, recurrence, disease status and shorter overall survival. Knockdown of TOPK with specific siRNA resulted in significantly decrease chordoma cell viability. Inhibition of TOPK with OTS514 significantly inhibited chordoma cell growth and proliferation, colony-forming capacity and ex vivo spheroid growth. CONCLUSIONS: High expression of TOPK is an important predictor of poor prognosis in chordoma. Inhibition of TOPK resulted in significantly decrease chordoma cell proliferation and increase apoptosis. Our results indicate TOPK as a novel prognostic biomarker and therapeutic target for chordoma.


Assuntos
Neoplasias Ósseas/patologia , Cordoma/patologia , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , Neoplasias Ósseas/metabolismo , Neoplasias Ósseas/mortalidade , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Cordoma/metabolismo , Cordoma/mortalidade , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Quinases de Proteína Quinase Ativadas por Mitógeno/antagonistas & inibidores , Quinases de Proteína Quinase Ativadas por Mitógeno/genética , Metástase Neoplásica , Prognóstico , Inibidores de Proteínas Quinases/farmacologia , Quinolonas/farmacologia , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Tiofenos/farmacologia
7.
PLoS Comput Biol ; 16(8): e1008106, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32797079

RESUMO

Antibiotic resistance is rising and we urgently need to gain a better quantitative understanding of how antibiotics act, which in turn would also speed up the development of new antibiotics. Here, we describe a computational model (COMBAT-COmputational Model of Bacterial Antibiotic Target-binding) that can quantitatively predict antibiotic dose-response relationships. Our goal is dual: We address a fundamental biological question and investigate how drug-target binding shapes antibiotic action. We also create a tool that can predict antibiotic efficacy a priori. COMBAT requires measurable biochemical parameters of drug-target interaction and can be directly fitted to time-kill curves. As a proof-of-concept, we first investigate the utility of COMBAT with antibiotics belonging to the widely used quinolone class. COMBAT can predict antibiotic efficacy in clinical isolates for quinolones from drug affinity (R2>0.9). To further challenge our approach, we also do the reverse: estimate the magnitude of changes in drug-target binding based on antibiotic dose-response curves. We overexpress target molecules to infer changes in antibiotic-target binding from changes in antimicrobial efficacy of ciprofloxacin with 92-94% accuracy. To test the generality of our approach, we use the beta-lactam ampicillin to predict target molecule occupancy at MIC from antimicrobial action with 90% accuracy. Finally, we apply COMBAT to predict antibiotic concentrations that can select for resistance due to novel resistance mutations. Using ciprofloxacin and ampicillin as well defined test cases, our work demonstrates that drug-target binding is a major predictor of bacterial responses to antibiotics. This is surprising because antibiotic action involves many additional effects downstream of drug-target binding. In addition, COMBAT provides a framework to inform optimal antibiotic dose levels that maximize efficacy and minimize the rise of resistant mutants.


Assuntos
Antibacterianos , Biologia Computacional/métodos , Desenvolvimento de Medicamentos/métodos , Quinolonas , Antibacterianos/química , Antibacterianos/metabolismo , Antibacterianos/farmacologia , Relação Dose-Resposta a Droga , Farmacorresistência Bacteriana/efeitos dos fármacos , Enterobacteriaceae/efeitos dos fármacos , Infecções por Enterobacteriaceae/microbiologia , Humanos , Testes de Sensibilidade Microbiana , Modelos Biológicos , Quinolonas/administração & dosagem , Quinolonas/química , Quinolonas/metabolismo , Quinolonas/farmacologia
8.
Int J Food Microbiol ; 330: 108692, 2020 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-32521291

RESUMO

Salmonella 4,[5],12:i:- is a monophasic variant of Salmonella Typhimurium, which is responsible for global foodborne disease outbreaks. Here, 255 S. 4,[5],12:i:- strains isolated from humans (11.0%) or food-borne animals (89.0%) between 2010 and 2018 were examined. Tests of susceptibility to 19 antimicrobial agents using the broth micro dilution method showed that 99.2% (n = 253) of the isolates were resistant to at least one compound. Antibiotic susceptibility analysis demonstrated that 91.8% of the isolates were multidrug-resistant (MDR) strains with predominant resistance to tetracycline (90.6%), followed by resistance to ampicillin (86.3%), streptomycin (63.5%), chloramphenicol (62.7%), and trimethoprim-sulfamethoxazole (55.3%). The 5 major distinct patterns of multi-resistance were identified as R-type AST, R-type ACTSxt, R-type ACSTSxt, R-type ACGSTSxt and R-type ASTSxt. Among the PMQR genes examined in this study, oqxAB and aac (6')-Ib-cr were the most prevalent resistance genes in the multi-resistant isolates. Our findings highlight the prevalence of the resistance of S. 4,[5],12:i:- in some regions of China, and several common types of multidrug resistance phenotypes, to provide valuable information for epidemiological studies, risk management, and public health strategies.


Assuntos
Antibacterianos/farmacologia , Farmacorresistência Bacteriana Múltipla/genética , Quinolonas/farmacologia , Salmonella/efeitos dos fármacos , Animais , China/epidemiologia , Humanos , Testes de Sensibilidade Microbiana , Prevalência , Salmonella/genética , Salmonella/isolamento & purificação , Infecções por Salmonella/epidemiologia , Infecções por Salmonella/microbiologia
9.
Nucleic Acids Res ; 48(13): 7454-7467, 2020 07 27.
Artigo em Inglês | MEDLINE | ID: mdl-32520327

RESUMO

Cystic fibrosis (CF) is an autosomal recessive disorder caused by mutations in the CF transmembrane conductance regulator (CFTR) gene, encoding an anion channel that conducts chloride and bicarbonate across epithelial membranes. Mutations that disrupt pre-mRNA splicing occur in >15% of CF cases. One common CFTR splicing mutation is CFTR c.3718-2477C>T (3849+10 kb C>T), which creates a new 5' splice site, resulting in splicing to a cryptic exon with a premature termination codon. Splice-switching antisense oligonucleotides (ASOs) have emerged as an effective therapeutic strategy to block aberrant splicing. We test an ASO targeting the CFTR c.3718-2477C>T mutation and show that it effectively blocks aberrant splicing in primary bronchial epithelial (hBE) cells from CF patients with the mutation. ASO treatment results in long-term improvement in CFTR activity in hBE cells, as demonstrated by a recovery of chloride secretion and apical membrane conductance. We also show that the ASO is more effective at recovering chloride secretion in our assay than ivacaftor, the potentiator treatment currently available to these patients. Our findings demonstrate the utility of ASOs in correcting CFTR expression and channel activity in a manner expected to be therapeutic in patients.


Assuntos
Regulador de Condutância Transmembrana em Fibrose Cística/genética , Fibrose Cística/metabolismo , Células Epiteliais/metabolismo , Oligodesoxirribonucleotídeos Antissenso/farmacologia , Processamento de RNA , Aminofenóis/farmacologia , Brônquios/citologia , Linhagem Celular Tumoral , Células Cultivadas , Agonistas dos Canais de Cloreto/farmacologia , Cloretos/metabolismo , Regulador de Condutância Transmembrana em Fibrose Cística/metabolismo , Células Epiteliais/efeitos dos fármacos , Humanos , Transporte de Íons/efeitos dos fármacos , Mutação , Quinolonas/farmacologia
10.
PLoS One ; 15(5): e0232710, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32384111

RESUMO

With the growing threat of antimicrobial resistance worldwide, uncovering the molecular epidemiology is critical for understanding what is driving this crisis. We aimed to evaluate the prevalence of plasmid-mediated-quinolone-resistance (PMQR) and extended-spectrum beta-lactamase- (ESBL) producing gram-negative organisms among primigravid women with bacteriuria. We collected urine specimens from primigravid women attending their first antenatal visit at Gandhi Hospital during October 1, 2015 to September 30, 2016. We determined antimicrobial susceptibility and ESBL and quinolone resistance using VITEK-2. We performed polymerase chain reaction amplification on resistant isolates for detection of ESBL-encoding genes (TEM, SHV, CTX-M) and PMQR genes (qnrA, qnrB, qnrD, qnrS, aac (6')-Ib-cr). Of 1,841 urine samples, 133 demonstrated significant bacterial growth with gram-negative bacilli accounting for 85% of isolates, including Escherichia coli (n = 79), Klebsiella pneumoniae (n = 29), Sphingomonas (n = 3), Enterobacter (n = 1), and Citrobacter (n = 1). We found 65% of E. coli isolates and 41% of K. pneumoniae isolates were ESBL positive. Of ESBL-positive isolates, the most common genes conferring resistance were TEM-1 (66.7%) followed by CTX-M-15 (33.3%). Fifty-seven percent of ESBL-positive E. coli also demonstrated resistance to quinolones with the most common PMQR genes being qnr-S (62.5%) and aac (6')-Ib-cr (37.5%). We did not find any resistance to quinolones among ESBL-positive K. pneumoniae isolates. Across different classes of antibiotics we found a strong clustering of multi-drug resistance in E. coli with over 45% of ESBL-positive isolates demonstrating resistance to at least three classes of antibiotics. This study emphasizes the high prevalence of plasmid-mediated ESBL and quinolone resistance in community-acquired urinary tract infections of primigravid women. The overall abundance of multi-drug-resistant isolates in this population is alarming and may present therapeutic challenges.


Assuntos
Resistência Microbiana a Medicamentos/genética , Plasmídeos/genética , Infecções Urinárias/microbiologia , Resistência Microbiana a Medicamentos/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Escherichia coli/genética , Escherichia coli/isolamento & purificação , Feminino , Genes Bacterianos , Humanos , Índia , Klebsiella pneumoniae/efeitos dos fármacos , Klebsiella pneumoniae/genética , Klebsiella pneumoniae/isolamento & purificação , Fenótipo , Gravidez , Quinolonas/farmacologia , beta-Lactamases/genética
11.
PLoS One ; 15(5): e0233439, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32469934

RESUMO

In epithelial cells, the cystic fibrosis transmembrane conductance regulator (CFTR), a cAMP-regulated Cl- channel, plays a key role in water and electrolytes secretion. A dysfunctional CFTR leads to the dehydration of the external environment of the cells and to the production of viscous mucus in the airways of cystic fibrosis patients. Here, we applied the quadriwave lateral shearing interferometry (QWLSI), a quantitative phase imaging technique based on the measurement of the light wave shift when passing through a living sample, to study water transport regulation in human airway epithelial CFBE and CHO cells expressing wild-type, G551D- and F508del-CFTR. We were able to detect phase variations during osmotic challenges and confirmed that cellular volume changes reflecting water fluxes can be detected with QWLSI. Forskolin stimulation activated a phase increase in all CFBE and CHO cell types. This phase variation was due to cellular volume decrease and intracellular refractive index increase and was completely blocked by mercury, suggesting an activation of a cAMP-dependent water efflux mediated by an endogenous aquaporin (AQP). AQP3 mRNAs, not AQP1, AQP4 and AQP5 mRNAs, were detected by RT-PCR in CFBE cells. Readdressing the F508del-CFTR protein to the cell surface with VX-809 increased the detected water efflux in CHO but not in CFBE cells. However, VX-770, a potentiator of CFTR function, failed to further increase the water flux in either G551D-CFTR or VX-809-corrected F508del-CFTR expressing cells. Our results show that QWLSI could be a suitable technique to study water transport in living cells. We identified a CFTR and cAMP-dependent, mercury-sensitive water transport in airway epithelial and CHO cells that might be due to AQP3. This water transport appears to be affected when CFTR is mutated and independent of the chloride channel function of CFTR.


Assuntos
Aquaporina 3/metabolismo , Regulador de Condutância Transmembrana em Fibrose Cística/metabolismo , Mucosa Respiratória/metabolismo , Água/metabolismo , Aminofenóis/farmacologia , Animais , Aquaporina 3/genética , Transporte Biológico Ativo/efeitos dos fármacos , Fenômenos Biofísicos , Brônquios/citologia , Brônquios/metabolismo , Células CHO , Linhagem Celular , Agonistas dos Canais de Cloreto/farmacologia , Colforsina/farmacologia , Cricetulus , Fibrose Cística/tratamento farmacológico , Fibrose Cística/genética , Fibrose Cística/metabolismo , Regulador de Condutância Transmembrana em Fibrose Cística/genética , Células Epiteliais/metabolismo , Humanos , Microscopia de Interferência , Proteínas Mutantes/genética , Proteínas Mutantes/metabolismo , Osmose , Quinolonas/farmacologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Mucosa Respiratória/citologia
12.
Cancer Invest ; 38(6): 349-355, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32441531

RESUMO

Background: Meningiomas represent ∼30% of primary central nervous system (CNS) tumors. Although advances in surgery and radiotherapy have significantly improved survival, there remains an important subset of patients whose tumors have more aggressive behavior and are refractory to conventional therapy. Recent advances in molecular genetics and epigenetics suggest that this aggressive behavior may be due to the deletion of the DNA repair and tumor suppressor gene, CHEK2, neurofibromatosis Type 2 (NF2) mutation on chromosome 22q12, and genetic abnormalities in multiple RTKs including FGFRs. Management of higher-grade meningiomas, such as anaplastic meningiomas (AM: WHO grade III), is truly challenging and there isn't an established chemotherapy option. We investigate the effect of active multi tyrosine receptor kinase inhibitor Dovitinib at stopping AM cell growth in in vitro with either frequent codeletion or mutated CHEK2 and NF2 gene.Methods: Treatment effects were assessed using MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay, western blot analysis, caspases assay, and DNA fragmentation assay.Results: Treatment of CH157MN and IOMM-Lee cells with Dovitinib suppressed multiple angiokinases-mainly FGFRs, leading to suppression of downstream signaling by RAS-RAF-MAPK molecules and PI3K-AKT molecules which are involved in cell proliferation, cell survival, and tumor invasion. Furthermore, Dovitinib induced apoptosis via downregulation of survival proteins (Bcl-XL), and over-expression of apoptotic factors (Bax and caspase-3) regardless of CHEK2 and NF2 mutation status.Conclusions: This study establishes the groundwork for the development of Dovitinib as a therapeutic agent for high-grade AM with either frequent codeletion or mutated CHEK2 and NF2, an avenue with high translational potential.


Assuntos
Benzimidazóis/farmacologia , Quinase do Ponto de Checagem 2/genética , Meningioma/tratamento farmacológico , Neurofibromina 2/genética , Quinolonas/farmacologia , Apoptose/efeitos dos fármacos , Caspase 3/genética , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Meningioma/genética , Meningioma/patologia , Mutação/genética , Estadiamento de Neoplasias , Fosfatidilinositol 3-Quinases/genética , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas c-akt/genética , Receptores de Fatores de Crescimento de Fibroblastos/antagonistas & inibidores , Receptores de Fatores de Crescimento de Fibroblastos/genética , Transdução de Sinais/efeitos dos fármacos , Proteína X Associada a bcl-2/genética , Proteína bcl-X/genética
13.
Sci Rep ; 10(1): 6721, 2020 04 21.
Artigo em Inglês | MEDLINE | ID: mdl-32317694

RESUMO

Patients diagnosed with T-cell leukemias and T-cell lymphomas (TCLs) still have a poor prognosis and an inadequate response to current therapies, highlighting the need for targeted treatments. We have analyzed the potential therapeutic value of the farnesyltransferase inhibitor, tipifarnib, in 25 TCL cell lines through the identification of genomic and/or immunohistochemical markers of tipifarnib sensitivity. More than half of the cell lines (60%) were considered to be sensitive. Tipifarnib reduced cell viability in these T-cell leukemia and TCL cell lines, induced apoptosis and modified the cell cycle. A mutational study showed TP53, NOTCH1 and DNMT3 to be mutated in 84.6%, 69.2% and 30.0% of sensitive cell lines, and in 62.5%, 0% and 0% of resistant cell lines, respectively. An immunohistochemistry study showed that p-ERK and RelB were associated as potential biomarkers of tipifarnib sensitivity and resistance, respectively. Data from RNA-seq show that tipifarnib at IC50 after 72 h downregulated a great variety of pathways, including those controlling cell cycle, metabolism, and ribosomal and mitochondrial activity. This study establishes tipifarnib as a potential therapeutic option in T-cell leukemia and TCL. The mutational state of NOTCH1, p-ERK and RelB could serve as potential biomarkers of tipifarnib sensitivity and resistance.


Assuntos
Biomarcadores Tumorais/metabolismo , Leucemia-Linfoma Linfoblástico de Células T Precursoras/tratamento farmacológico , Quinolonas/uso terapêutico , Apoptose/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Regulação para Baixo/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/genética , Regulação Leucêmica da Expressão Gênica/efeitos dos fármacos , Humanos , Concentração Inibidora 50 , Linfoma de Células T/tratamento farmacológico , Linfoma de Células T/genética , Linfoma de Células T/patologia , Mutação/genética , Fenótipo , Leucemia-Linfoma Linfoblástico de Células T Precursoras/genética , Leucemia-Linfoma Linfoblástico de Células T Precursoras/patologia , Quinolonas/farmacologia , Transdução de Sinais/efeitos dos fármacos , Linfócitos T/efeitos dos fármacos , Linfócitos T/imunologia
14.
Eur J Med Chem ; 192: 112156, 2020 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-32114360

RESUMO

Androgen receptor (AR) plays important roles in the development of prostate cancer (PCa), and therefore it has been regarded as the most important therapeutic target for both hormone-sensitive prostate cancer (HSPC) and advanced PCa. In this study, a novel hit (C18) with IC50 of 2.4 µM against AR transcriptional activity in LNCaP cell was identified through structure-based virtual screening based on molecular docking and free energy calculations. The structure-activity relationship analysis and structural optimization of C18 resulted in the discovery of a structural analogue (AT2), a more potent AR antagonist with 16-fold improved anti-AR potency. Further assays indicated that AT2 was capable of effectively inhibiting the transcriptional function of AR and blocking the nuclear translocation of AR like the second-generation AR antagonists. The antagonists discovered in this study may be served as the promising lead compounds for the development of AR-driven PCa therapeutics.


Assuntos
Antagonistas de Receptores de Andrógenos/farmacologia , Quinolonas/farmacologia , Células 3T3 , Antagonistas de Receptores de Andrógenos/síntese química , Antagonistas de Receptores de Andrógenos/química , Animais , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Avaliação Pré-Clínica de Medicamentos , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Camundongos , Simulação de Acoplamento Molecular , Estrutura Molecular , Quinolonas/síntese química , Quinolonas/química , Relação Estrutura-Atividade , Células Tumorais Cultivadas
15.
J Med Chem ; 63(7): 3577-3595, 2020 04 09.
Artigo em Inglês | MEDLINE | ID: mdl-32141297

RESUMO

Free fatty acid receptor 3 (FFA3, previously GPR41) is activated by short-chain fatty acids, mediates health effects of the gut microbiota, and is a therapeutic target for metabolic and inflammatory diseases. The shortage of well-characterized tool compounds has however impeded progress. Herein, we report structure-activity relationship of an allosteric modulator series and characterization of physicochemical and pharmacokinetic properties of selected compounds, including previous and new tools. Two representatives, 57 (TUG-1907) and 63 (TUG-2015), showed improved solubility and preserved potency. Of these, 57, with EC50 = 145 nM and a solubility of 33 µM, showed high clearance in vivo but is a preferred tool in vitro. In contrast, 63, with EC50 = 162 nM and a solubility of 9 µM, showed lower clearance and seems better suited for in vivo studies. Using 57, we demonstrate for the first time that FFA3 activation leads to calcium mobilization in murine dorsal root ganglia.


Assuntos
Quinolonas/farmacologia , Receptores Acoplados a Proteínas-G/metabolismo , Regulação Alostérica , Animais , Estabilidade de Medicamentos , Gânglios Espinais/efeitos dos fármacos , Humanos , Camundongos Knockout , Microssomos Hepáticos/metabolismo , Simulação de Acoplamento Molecular , Estrutura Molecular , Quinolonas/síntese química , Quinolonas/metabolismo , Quinolonas/farmacocinética , Receptores Acoplados a Proteínas-G/genética , Relação Estrutura-Atividade
16.
Eur J Med Chem ; 193: 112222, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32200200

RESUMO

In the search for novel hybrid molecules by fusing two biologically active scaffolds into one heteromeric chemotype, we found that hybrids of azithromycin and ciprofloxacin/gatifloxacin 26j and 26l can inhibit the supercoiling activity of E. coli gyrase by poisoning it in a way similar to fluoroquinolones. This may modestly contribute to their potencies, which are equal to ciprofloxacin against constitutively resistant Staphylococcus aureus, whose growth is not inhibited by the presence of macrolides. In contrast, introduction of quinolines (the 3-quinoline 26b and the 6-quinoline 26o) with an optimized rigid spacer at the 6-OH of azithromycin acylides did not exert significant potency against constitutively resistant S. aureus, despite the fact that the quinoline-containing compounds, exemplified by 26o, were as active as telithromycin against susceptible, inducibly- and efflux-resistant pathogens. The novel dual modes of action involving protein synthesis inhibition and poisoning DNA replication may pave the way for restoration of antibacterial activities of the current macrolides against constitutively resistant clinical isolates.


Assuntos
Antibacterianos/farmacologia , Azitromicina/farmacologia , Macrolídeos/farmacologia , Quinolinas/farmacologia , Quinolonas/farmacologia , Inibidores da Topoisomerase II/farmacologia , Antibacterianos/síntese química , Antibacterianos/química , Azitromicina/química , DNA Topoisomerases Tipo II/metabolismo , Relação Dose-Resposta a Droga , Desenho de Fármacos , Escherichia coli/enzimologia , Macrolídeos/síntese química , Macrolídeos/química , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Estrutura Molecular , Quinolinas/química , Quinolonas/química , Relação Estrutura-Atividade , Inibidores da Topoisomerase II/síntese química , Inibidores da Topoisomerase II/química
17.
Sci Rep ; 10(1): 3835, 2020 03 02.
Artigo em Inglês | MEDLINE | ID: mdl-32123217

RESUMO

The use of antiretroviral therapy (ART) has remarkably decreased the morbidity associated with HIV-1 infection, however, the prevalence of HIV-1-associated neurocognitive disorders (HAND) is still increasing. The blood-brain barrier (BBB) is the major impediment for penetration of antiretroviral drugs, causing therapeutics to reach only suboptimal level to the brain. Conventional antiretroviral drug regimens are not sufficient to improve the treatment outcomes of HAND. In our recent report, we have developed a poloxamer-PLGA nanoformulation loaded with elvitegravir (EVG), a commonly used antiretroviral drug. The nanoformulated EVG is capable of elevating intracellular drug uptake and simultaneously enhance viral suppression in HIV-1-infected macrophages. In this work, we identified the clinical parameters including stability, biocompatibility, protein corona, cellular internalization pathway of EVG nanoformulation for its potential clinical translation. We further assessed the ability of this EVG nanoformulation to cross the in vitro BBB model and suppress the HIV-1 in macrophage cells. Compared with EVG native drug, our EVG nanoformulation demonstrated an improved BBB model penetration cross the in vitro BBB model and an enhanced HIV-1 suppression in HIV-1-infected human monocyte-derived macrophages after crossing the BBB model without altering the BBB model integrity. Overall, this is an innovative and optimized treatment strategy that has a potential for therapeutic interventions in reducing HAND.


Assuntos
Barreira Hematoencefálica/metabolismo , Composição de Medicamentos , HIV-1/efeitos dos fármacos , Macrófagos/virologia , Nanopartículas/química , Quinolonas/química , Quinolonas/farmacologia , Fármacos Anti-HIV/química , Fármacos Anti-HIV/metabolismo , Fármacos Anti-HIV/farmacologia , Linhagem Celular , Relação Dose-Resposta a Droga , Portadores de Fármacos/química , Humanos , Teste de Materiais , Tamanho da Partícula , Poloxâmero/química , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/química , Quinolonas/metabolismo
18.
Eur J Med Chem ; 192: 112176, 2020 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-32120327

RESUMO

We have synthesized a series of 2-phenyl-3-hydroxy-4(1H)-quinolinone derivatives substituted with one or more fluorine atoms on the quinolone backbone as well as on phenyl ring. The derivatives bearing more fluorine atoms were subjected to modification by nucleophilic substitutions by thiophenol, morpholine, and piperazine derivative. We have tested the prepared compounds in cytotoxic activity assay against cancer cell lines. Four derivatives exhibited micromolar values of IC50 against some of the cancer cell lines, and we have subjected them to cell cycle analysis on CCRF-CEM. Moreover, most active 7-fluoro-3-hydroxy-2-phenyl-6-(phenylthio)quinolin-4(1H)-one inhibits mitosis progression. Cell cycle analysis, in vitro tubulin polymerization assay, and tubulin imaging in cells indicated that the anticancer activity of thiophenol derivative is associated with its ability to inhibit microtubule formation.


Assuntos
Quinolonas/farmacologia , Moduladores de Tubulina/farmacologia , Tubulina (Proteína)/metabolismo , Relação Dose-Resposta a Droga , Células HCT116 , Halogenação , Humanos , Estrutura Molecular , Polimerização/efeitos dos fármacos , Quinolonas/síntese química , Quinolonas/química , Relação Estrutura-Atividade , Moduladores de Tubulina/síntese química , Moduladores de Tubulina/química
19.
Sci Rep ; 10(1): 3937, 2020 03 03.
Artigo em Inglês | MEDLINE | ID: mdl-32127598

RESUMO

For a One-Health investigation of antimicrobial resistance (AMR) in Enterococcus spp., isolates from humans and beef cattle along with abattoirs, manured fields, natural streams, and wastewater from both urban and cattle feedlot sources were collected over two years. Species identification of Enterococcus revealed distinct associations across the continuum. Of the 8430 isolates collected, Enterococcus faecium and Enterococcus faecalis were the main species in urban wastewater (90%) and clinical human isolates (99%); Enterococcus hirae predominated in cattle (92%) and feedlot catch-basins (60%), whereas natural streams harbored environmental Enterococcus spp. Whole-genome sequencing of E. faecalis (n = 366 isolates) and E. faecium (n = 342 isolates), revealed source clustering of isolates, indicative of distinct adaptation to their respective environments. Phenotypic resistance to tetracyclines and macrolides encoded by tet(M) and erm(B) respectively, was prevalent among Enterococcus spp. regardless of source. For E. faecium from cattle, resistance to ß-lactams and quinolones was observed among 3% and 8% of isolates respectively, compared to 76% and 70% of human clinical isolates. Clinical vancomycin-resistant E. faecium exhibited high rates of multi-drug resistance, with resistance to all ß-lactam, macrolides, and quinolones tested. Differences in the AMR profiles among isolates reflected antimicrobial use practices in each sector of the One-Health continuum.


Assuntos
Antibacterianos/farmacologia , Enterococcus/patogenicidade , Farmacorresistência Bacteriana/genética , Enterococcus/efeitos dos fármacos , Enterococcus/genética , Enterococcus faecalis/efeitos dos fármacos , Enterococcus faecalis/genética , Enterococcus faecalis/patogenicidade , Enterococcus faecium/efeitos dos fármacos , Enterococcus faecium/genética , Enterococcus faecium/patogenicidade , Humanos , Macrolídeos/farmacologia , Filogenia , Quinolonas/farmacologia , Tetraciclinas/farmacologia , Virulência , Sequenciamento Completo do Genoma , Resistência beta-Lactâmica/genética
20.
J Appl Oral Sci ; 28: e20190156, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32049134

RESUMO

OBJECTIVE: The present study aimed to investigate the participation of focal adhesion kinases (FAK) in interactions between osteoblastic cells and titanium (Ti) surfaces with three different topographies, namely, untreated (US), microstructured (MS), and nanostructured (NS). METHODOLOGY: Osteoblasts harvested from the calvarial bones of 3-day-old rats were cultured on US, MS and NS discs in the presence of PF-573228 (FAK inhibitor) to evaluate osteoblastic differentiation. After 24 h, we evaluated osteoblast morphology and vinculin expression, and on day 10, the following parameters: gene expression of osteoblastic markers and integrin signaling components, FAK protein expression and alkaline phosphatase (ALP) activity. A smooth surface, porosities at the microscale level, and nanocavities were observed in US, MS, and NS, respectively. RESULTS: FAK inhibition decreased the number of filopodia in cells grown on US and MS compared with that in NS. FAK inhibition decreased the gene expression of Alp, bone sialoprotein, osteocalcin, and ALP activity in cells grown on all evaluated surfaces. FAK inhibition did not affect the gene expression of Fak, integrin alpha 1 ( Itga1 ) and integrin beta 1 ( Itgb1 ) in cells grown on MS, increased the gene expression of Fak in cells grown on NS, and increased the gene expression of Itga1 and Itgb1 in cells grown on US and NS. Moreover, FAK protein expression decreased in cells cultured on US but increased in cells cultured on MS and NS after FAK inhibition; no difference in the expression of vinculin was observed among cells grown on all surfaces. CONCLUSIONS: Our data demonstrate the relevance of FAK in the interactions between osteoblastic cells and Ti surfaces regardless of surface topography. Nanotopography positively regulated FAK expression and integrin signaling pathway components during osteoblast differentiation. In this context, the development of Ti surfaces with the ability to upregulate FAK activity could positively impact the process of implant osseointegration.


Assuntos
Proteína-Tirosina Quinases de Adesão Focal/antagonistas & inibidores , Osteoblastos/efeitos dos fármacos , Quinolonas/farmacologia , Sulfonas/farmacologia , Titânio/química , Animais , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Proteína-Tirosina Quinases de Adesão Focal/análise , Proteína-Tirosina Quinases de Adesão Focal/química , Expressão Gênica , Integrinas/análise , Microscopia Eletrônica de Varredura , Osseointegração/efeitos dos fármacos , Osteoblastos/fisiologia , Quinolonas/química , Ratos Wistar , Reação em Cadeia da Polimerase em Tempo Real , Transdução de Sinais , Sulfonas/química , Propriedades de Superfície
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