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1.
BMC Immunol ; 25(1): 37, 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38937711

RESUMO

BACKGROUND: Although immune checkpoint inhibitors (ICIs) have brought survival benefits to non-small cell lung cancer (NSCLC), disease progression still occurs, and there is no consensus on the treatment options for these patients. We designed a network meta-analysis (NMA) to evaluate systemic treatment options for NSCLC after failure of ICIs. METHODS: PubMed, Embase, Web of Science and Cochrane Library databases were searched, then literature screening was followed by NMA. We included all Phase II and III randomized controlled trials (RCTs). Progression-free survival (PFS) and overall survival (OS) used hazard ratio (HR) for evaluation. Objective response rate (ORR) and adverse events (AEs) used odds ratio (OR) and relative risk (RR) effect sizes, respectively. R software was applied to compare the Bayesian NMA results. RESULTS: We finally included 6 studies. 1322 patients received ICI plus Chemotherapy (ICI + Chemo), ICI plus Anti-angiogenic monoclonal antibody (ICI + Antiangio-Ab), ICI plus Tyrosine kinase inhibitor (ICI + TKI), Tyrosine kinase inhibitor plus Chemotherapy (TKI + Chemo), Standard of Care (SOC), Chemotherapy (Chemo). TKI + Chemo is associated with longer PFS, higher ORR (surface under cumulative ranking curve [SUCRA], 99.7%, 88.2%), ICI + TKI achieved the longest OS (SUCRA, 82.7%). ICI + Antiangio-Ab was granted the highest safety rating for adverse events (AEs) of any grade, AEs greater than or equal to grade 3 and AEs of any grade leading to discontinuation of treatment (SUCRA, 95%, 82%, 93%). CONCLUSIONS: For NSCLC after failure of ICIs, TKI + Chemo was associated with longer PFS and higher ORR, while ICI + TKI was associated with the longest OS. In terms of safety, ICI + Antiangio-Ab was the highest.


Assuntos
Teorema de Bayes , Carcinoma Pulmonar de Células não Pequenas , Inibidores de Checkpoint Imunológico , Neoplasias Pulmonares , Metanálise em Rede , Ensaios Clínicos Controlados Aleatórios como Assunto , Humanos , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/mortalidade , Carcinoma Pulmonar de Células não Pequenas/imunologia , Inibidores de Checkpoint Imunológico/uso terapêutico , Inibidores de Checkpoint Imunológico/efeitos adversos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/mortalidade , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos
2.
Int J Hyperthermia ; 41(1): 2328113, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38964750

RESUMO

PURPOSE: This study aimed to investigate the efficacy and safety of ultrasound-guided percutaneous radiofrequency ablation (RFA) for the treatment of synovial hyperplasia in the knee joints of antigen-induced arthritis (AIA) model rabbits. METHODS: Forty Japanese large-eared white rabbits were divided into AIA and control groups. After successful induction of the AIA model, the knee joints were randomly assigned to RFA and non-RFA groups. The RFA group underwent ultrasound-guided RFA to treat synovial hyperplasia in the knee joint. Dynamic observation of various detection indices was conducted to evaluate the safety and effectiveness of the RFA procedure. RESULTS: Successful synovial ablation was achieved in the RFA group, with no intraoperative or perioperative mortality. Postoperative the circumference of the knee joint reached a peak before decreasing in the third week after surgery. The incidence and diameter of postoperative skin ulcers were not significantly different compared to the non-RFA group (p > .05). Anatomical examination revealed an intact intermuscular fascia around the ablated area in the RFA group. The ablated synovial tissue initially presented as a white mass, which subsequently liquefied into a milky white viscous fluid. Gross articular cartilage was observed, along with liquefied necrosis of the synovium on pathological histology and infiltration of inflammatory cells in the surrounding soft tissue. CONCLUSION: The experimental results demonstrated that ultrasound-guided RFA of the knee in the treatment of synovial hyperplasia in AIA model animals was both effective and safe.


Assuntos
Hiperplasia , Ablação por Radiofrequência , Animais , Coelhos , Ablação por Radiofrequência/métodos , Hiperplasia/cirurgia , Hiperplasia/patologia , Membrana Sinovial/patologia , Membrana Sinovial/diagnóstico por imagem , Ultrassonografia/métodos , Masculino , Ultrassonografia de Intervenção/métodos
3.
Acta Pharmacol Sin ; 44(10): 1977-1988, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37217602

RESUMO

Atherosclerotic diseases remain the leading cause of adult mortality and impose heavy burdens on health systems globally. Our previous study found that disturbed flow enhanced YAP activity to provoke endothelial activation and atherosclerosis, and targeting YAP alleviated endothelial inflammation and atherogenesis. Therefore, we established a luciferase reporter assay-based drug screening platform to seek out new YAP inhibitors for anti-atherosclerotic treatment. By screening the FDA-approved drug library, we identified that an anti-psychotic drug thioridazine markedly suppressed YAP activity in human endothelial cells. Thioridazine inhibited disturbed flow-induced endothelial inflammatory response in vivo and in vitro. We verified that the anti-inflammatory effects of thioridazine were mediated by inhibition of YAP. Thioridazine regulated YAP activity via restraining RhoA. Moreover, administration of thioridazine attenuated partial carotid ligation- and western diet-induced atherosclerosis in two mouse models. Overall, this work opens up the possibility of repurposing thioridazine for intervention of atherosclerotic diseases. This study also shed light on the underlying mechanisms that thioridazine inhibited endothelial activation and atherogenesis via repression of RhoA-YAP axis. As a new YAP inhibitor, thioridazine might need further investigation and development for the treatment of atherosclerotic diseases in clinical practice.


Assuntos
Aterosclerose , Células Endoteliais , Tioridazina , Animais , Humanos , Camundongos , Aterosclerose/tratamento farmacológico , Aterosclerose/prevenção & controle , Inflamação/etiologia , Proteína rhoA de Ligação ao GTP/efeitos dos fármacos , Tioridazina/uso terapêutico , Proteínas de Sinalização YAP/efeitos dos fármacos
4.
Breast Cancer Res ; 24(1): 12, 2022 02 12.
Artigo em Inglês | MEDLINE | ID: mdl-35151363

RESUMO

BACKGROUND: Preclinical and epidemiological studies indicate a potential chemopreventive role of low-density lipoprotein cholesterol (LDL-C) -lowering drugs in the risks of breast cancer and prostate cancer, but the causality remains unclear. We aimed to evaluate the association of genetically proxied inhibition of 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase, Niemann-Pick C1-Like 1 (NPC1L1), and proprotein convertase subtilisin/kexin type 9 (PCSK9) with risks of breast cancer and prostate cancer using a two-sample Mendelian randomization (MR) method. METHODS: Single-nucleotide polymorphisms (SNPs) in HMGCR, NPC1L1, and PCSK9 associated with LDL-C in a genome-wide association study (GWAS) meta-analysis from the Global Lipids Genetics Consortium (GLGC; up to 188,577 European individuals) were used to proxy inhibition of HMG-CoA reductase, NPC1L1, and PCSK9. Summary statistics with outcomes were obtained from a GWAS meta-analysis of the Breast Cancer Association Consortium (BCAC; 228,951 European females) and a Prostate Cancer Association Group to Investigate Cancer Associated Alterations in the Genome (PRACTICAL; 140,254 European males) consortium. SNPs were combined into multiallelic models and MR estimates representing lifelong inhibition of targets were generated using the inverse-variance weighted method. RESULTS: Genetically proxied inhibition of HMG-CoA reductase (OR: 0.84; 95% CI 0.74-0.95; P = 0.005) and NPC1L1 (OR: 0.72; 95% CI 0.58-0.90; P = 0.005) equivalent to a 1-mmol/L (38.7 mg/dL) reduction in LDL-C was associated with reduced breast cancer risk. There were no significant associations of genetically proxied inhibition of PCSK9 with breast cancer. In contrast, genetically proxied inhibition of PCSK9 (OR: 0.81; 95% CI 0.73-0.90; P < 0.001) but not HMG-CoA reductase and NPC1L1 was negatively associated with prostate cancer. In the secondary analysis, genetically proxied inhibition of HMG-CoA reductase (OR: 0.82; 95% CI 0.71-0.95; P = 0.008) and NPC1L1 (OR: 0.66; 95% CI 0.50-0.86; P = 0.002) was associated with estrogen receptor-positive breast cancer, whereas there was no association of HMG-CoA reductase and NPC1L1 with estrogen receptor-negative breast cancer. CONCLUSIONS: Genetically proxied inhibition of HMG-CoA reductase and NPC1L1 was significantly associated with lower odds of breast cancer, while genetically proxied inhibition of PCSK9 was associated with reduced risk of prostate cancer. Further randomized controlled trials are needed to confirm the respective roles of these LDL-C-lowering drugs in breast cancer and prostate cancer.


Assuntos
Neoplasias da Mama , Inibidores de Hidroximetilglutaril-CoA Redutases , Neoplasias da Próstata , Acil Coenzima A , Neoplasias da Mama/epidemiologia , Neoplasias da Mama/genética , LDL-Colesterol/genética , Coenzima A , Estudo de Associação Genômica Ampla , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Masculino , Proteínas de Membrana Transportadoras/genética , Análise da Randomização Mendeliana , Oxirredutases , Pró-Proteína Convertase 9/genética , Neoplasias da Próstata/genética , Receptores de Estrogênio/genética
5.
J Org Chem ; 87(2): 1526-1536, 2022 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-34995462

RESUMO

Here we demonstrate the feasibility and efficiency of simple iridium-based catalytic systems in the synthesis of multisubstituted alkenyl boronates from internal alkynes with high selectivities. A variety of alkynes were smoothly decorated with HBpin under a mild [Ir(cod)Cl]2/dppm/acetone condition to afford trisubstituted alkenyl boronic esters with up to >99:1 regioselectivity. The diboration reaction could effectively occur in the presence of [Ir(cod)Cl]2/DCM. Plausible mechanisms were provided to illustrate these two catalytic processes, in which the intrinsic functional group of the alkyne was supposed to be important in facilitating these reactions as well as the regioselectivity.

6.
Bioorg Chem ; 118: 105474, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34794102

RESUMO

The worldwide prevalence of NDM-1-producing Gram-negative pathogens has drastically undermined the clinical efficacy of carbapenems, prompting a need to devise an effective strategy to preserve their clinical value. Here we constructed a focused compound library of dithiocarbamates and systematically evaluated their potential synergistic antibacterial activities combined with copper. SA09-Cu exhibited excellent inhibition against a series of clinical NDM-1-producing carbapenem-resistant Enterobacteriaceae (CRE) in restoring meropenem effect, and slowed down the development of carbapenem resistance. Enzymatic kinetic and isothermal titration calorimetry studies demonstrated that SA09-Cu was a noncompetitive NDM-1 inhibitor. The electron paramagnetic resonance (EPR) and X-ray photoelectron spectroscopy (XPS) revealed a novel inhibition mechanism, which is that SA09-Cu could convert NDM-1 into an inactive state by oxidizing the Zn(II)-thiolate site of the enzyme. Importantly, SA09-Cu showed a unique redox tuning ability, and avoided to be reduced by intracellular thiols of bacteria. In vivo experiments indicated that SA09 combined with CuGlu could effectively potentiate MER's effect against NDM-1-producing E. coli (EC23) in the murine infection model. This study provides a highly promising scaffold in developing novel inhibitors to combat NDM-1-producing CREs.


Assuntos
Antibacterianos/farmacologia , Enterobacteriáceas Resistentes a Carbapenêmicos/efeitos dos fármacos , Complexos de Coordenação/farmacologia , Cobre/farmacologia , Inibidores Enzimáticos/farmacologia , Tiocarbamatos/farmacologia , beta-Lactamases/metabolismo , Antibacterianos/síntese química , Antibacterianos/química , Enterobacteriáceas Resistentes a Carbapenêmicos/enzimologia , Complexos de Coordenação/síntese química , Complexos de Coordenação/química , Cobre/química , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/química , Escherichia coli/efeitos dos fármacos , Escherichia coli/enzimologia , Testes de Sensibilidade Microbiana , Estrutura Molecular , Relação Estrutura-Atividade , Tiocarbamatos/química
7.
Bioorg Chem ; 120: 105654, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35149265

RESUMO

The "superbug" infection caused by metallo-ß-lactamases (MßLs) has grown into anemergent health threat, and development of effective MßL inhibitors to restore existing antibiotic efficacy is an ideal alternative. Although the serine-ß-lactamase inhibitors have been used in clinical settings, MßL inhibitors are not available to date. In this work, thirty-one quinolinyl sulfonamides 1a-p and sulphonyl esters 2a-o were synthesized and assayed against MßL NDM-1. The obtained molecules specifically inhibited NDM-1, 1a-p and 2a-o exhibited an IC50 value in the range of 0.02-1.4 and 8.3-24.8 µM, respectively, and 1e and 1f were found to be the most potent inhibitors, with an IC50 of 0.02 µM using meropenem (MER) as substrate. Structure-activity relationship reveals that the substitute phenyl and the phenyl with a halogen atom more significantly improve inhibitory effect of quinolinederivatives on NDM-1. 1a-p restored antimicrobial effect of MER on E. coli with NDM-1, EC01 and EC08, resulting in a 2-64-fold reduction in MIC values. Most importantly, 1e synergized MER and significantly reduced the load of EC08 in the spleen and liver of mice after a single intraperitoneal dose. Docking studies suggested that the endocyclic nitrogen of the quinoline ring, and exocyclic nitrogen of the sulfonamide functional group are coordinate with Zn(II) ion at active sites of NDM-1. Cytotoxicity assays indicated that 1e had low cytotoxicity. This work offers potential lead compounds for further development of the clinically useful inhibitor targeting NDM-1.


Assuntos
Escherichia coli , Ésteres , Animais , Antibacterianos/química , Antibacterianos/farmacologia , Ésteres/farmacologia , Camundongos , Testes de Sensibilidade Microbiana , Nitrogênio/farmacologia , Sulfanilamida/farmacologia , Sulfonamidas/farmacologia , beta-Lactamases/química
8.
Bioorg Chem ; 124: 105799, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35462235

RESUMO

The emerging COVID-19 pandemic generated by Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) has severely threatened human health. The main protease (Mpro) of SARS-CoV-2 is promising target for antiviral drugs, which plays a vital role for viral duplication. Development of the inhibitor against Mpro is an ideal strategy to combat COVID-19. In this work, twenty-three hydroxamates 1a-i and thiosemicarbazones 2a-n were identified by FRET screening to be the potent inhibitors of Mpro, which exhibited more than 94% (except 1c) and more than 69% inhibition, and an IC50 value in the range of 0.12-31.51 and 2.43-34.22 µM, respectively. 1a and 2b were found to be the most effective inhibitors in the hydroxamates and thiosemicarbazones, with an IC50 of 0.12 and 2.43 µM, respectively. Enzyme kinetics, jump dilution and thermal shift assays revealed that 2b is a competitive inhibitor of Mpro, while 1a is a time-dependently inhibitor; 2b reversibly but 1a irreversibly bound to the target; the binding of 2b increased but 1a decreased stability of the target, and DTT assays indicate that 1a is the promiscuous cysteine protease inhibitor. Cytotoxicity assays showed that 1a has low, but 2b has certain cytotoxicity on the mouse fibroblast cells (L929). Docking studies revealed that the benzyloxycarbonyl carbon of 1a formed thioester with Cys145, while the phenolic hydroxyl oxygen of 2b formed H-bonds with Cys145 and Asn142. This work provided two promising scaffolds for the development of Mpro inhibitors to combat COVID-19.


Assuntos
Tratamento Farmacológico da COVID-19 , Tiossemicarbazonas , Animais , Antivirais/química , Proteases 3C de Coronavírus , Humanos , Camundongos , Simulação de Acoplamento Molecular , Pandemias , Inibidores de Proteases/química , SARS-CoV-2 , Tiossemicarbazonas/farmacologia
9.
Bioorg Chem ; 127: 105928, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35717802

RESUMO

The superbug infection mediated by metallo-ß-lactamases (MßLs) has grown into anemergent health threat, and development of MßL inhibitors is an ideal strategy to combat the infection. In this work, twenty-five thiosemicarbazones 1a-e, 2a-e, 3a-e, 4a-d, 5a-d and 6a-b were synthesized and assayed against MßLs ImiS, NDM-1 and L1. The gained molecules specifically inhibited NDM-1 and ImiS, exhibiting an IC50 value in the range of 0.37-21.35 and 0.45-8.76 µM, and 2a was found to be the best inhibitor, with an IC50 of 0.37 and 0.45 µM, respectively, using meropenem (MER) as substrate. Enzyme kinetics and dialysis tests revealed and confirmed by ITC that 2a is a time-and dose-dependent inhibitor of ImiS and NDM-1, it competitively and reversibly inhibited ImiS with a Ki value of 0.29 µM, but irreversibly inhibited NDM-1. Structure-activity relationship disclosed that the substitute dihydroxylbenzene significantly enhanced inhibitory activity of thiosemicarbazones on ImiS and NDM-1. Most importantly, 1a-e, 2a-e and 3a-b alone more strongly sterilized E. coli-ImiS and E. coli-NDM-1 than the MER, displaying a MIC value in the range of 8-128 µg/mL, and 2a was found to be the best reagent with a MIC of 8 and 32 µg/mL. Also, 2a alone strongly sterilized the clinical isolates EC01, EC06-EC08, EC24 and K. pneumonia-KPC-NDM, showing a MIC value in the range of 16-128 µg/mL, and exhibited synergistic inhibition with MER on these bacteria tested, resulting in 8-32-fold reduction in MIC of MER. SEM images shown that the bacteria E. coli-ImiS, E. coli-NDM-1, EC24, K. pneumonia-KPC and K. pneumonia-KPC-NDM treated with 2a (64 µg/mL) suffered from distortion, emerging adhesion between individual cells and crumpled membranes. Mice tests shown that monotherapy of 2a evidently limited growth of EC24 cells, and in combination with MER, it significantly reduced the bacterial load in liver and spleen. Docking studies suggest that the 2,4-dihydroxylbenzene of 2a acts as zinc-binding group with the Zn(II) and the residual amino acids in CphA active center, tightly anchoring the inhibitor at active site. This work offered a promising scaffold for the development of MßLs inhibitors, specifically the antimicrobial for clinically drug-resistant isolates.


Assuntos
Tiossemicarbazonas , Inibidores de beta-Lactamases , Animais , Antibacterianos/química , Antibacterianos/farmacologia , Bactérias/metabolismo , Escherichia coli , Camundongos , Testes de Sensibilidade Microbiana , Tiossemicarbazonas/farmacologia , Inibidores de beta-Lactamases/química , Inibidores de beta-Lactamases/farmacologia , beta-Lactamases/metabolismo
10.
Molecules ; 27(18)2022 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-36144828

RESUMO

Salvianic acid A (SAA), as the main bioactive component of the traditional Chinese herb Salvia miltiorrhiza, has important application value in the treatment of cardiovascular diseases. In this study, a two-step bioprocess for the preparation of SAA from l-DOPA was developed. In the first step, l-DOPA was transformed to 3,4-dihydroxyphenylalanine (DHPPA) using engineered Escherichia coli cells expressing membrane-bound L-amino acid deaminase from Proteus vulgaris. After that, the unpurified DHPPA was directly converted into SAA by permeabilized recombinant E. coli cells co-expressing d-lactate dehydrogenase from Pediococcus acidilactici and formate dehydrogenase from Mycobacterium vaccae N10. Under optimized conditions, 48.3 mM of SAA could be prepared from 50 mM of l-DOPA, with a yield of 96.6%. Therefore, the bioprocess developed here was not only environmentally friendly, but also exhibited excellent production efficiency and, thus, is promising for industrial SAA production.


Assuntos
Escherichia coli , Levodopa , Biocatálise , Escherichia coli/genética , Formiato Desidrogenases , Ácidos Fenilpirúvicos
11.
Org Biomol Chem ; 19(28): 6216-6220, 2021 07 21.
Artigo em Inglês | MEDLINE | ID: mdl-34195740

RESUMO

Here we reported the iridium-catalyzed hydrosilylation of internal alkynes under simple and mild conditions. The intrinsic functional groups of alkyne substrates were disclosed to be crucial in facilitating both the hydrosilylation process and related regioselectivity owing to their coordination capability towards the iridium catalyst. Utilization of the steric trimethylsilyl-protected trihydroxysilane proved to be another critical factor in ensuring the efficient proceeding of this process.

12.
Bioorg Med Chem ; 38: 116128, 2021 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-33862468

RESUMO

To combat the superbug infection caused by metallo-ß-lactamases (MßLs), a dipyridyl-substituted thiosemicarbazone (DpC), was identified to be the broad-spectrum inhibitor of MßLs (NDM-1, VIM-2, IMP-1, ImiS, L1), with an IC50 value in the range of 0.021-1.08 µM. It reversibly and competitively inhibited NDM-1 with a Ki value of 10.2 nM. DpC showed broad-spectrum antibacterial effect on clinical isolate K. pneumonia, CRE, VRE, CRPA and MRSA, with MIC value ranged from 16 to 32 µg/mL, and exhibited synergistic antibacterial effect with meropenem on MßLs-producing bacteria, resulting in a 2-16-, 2-8-, and 8-fold reduction in MIC of meropenem against EC-MßLs, EC01-EC24, K. pneumonia, respectively. Moreover, mice experiments showed that DpC also had synergistic antibacterial action with meropenem. In this work, DpC was identified to be a potent scaffold for the development of broad-spectrum inhibitors of MßLs.


Assuntos
Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Tiossemicarbazonas/farmacologia , Inibidores de beta-Lactamases/farmacologia , beta-Lactamases/metabolismo , Antibacterianos/síntese química , Antibacterianos/química , Bactérias/enzimologia , Relação Dose-Resposta a Droga , Testes de Sensibilidade Microbiana , Estrutura Molecular , Relação Estrutura-Atividade , Tiossemicarbazonas/síntese química , Tiossemicarbazonas/química , Inibidores de beta-Lactamases/síntese química , Inibidores de beta-Lactamases/química
13.
Bioorg Chem ; 107: 104576, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33383326

RESUMO

The superbug infection caused by New Delhi metallo-ß-lactamase (NDM-1) has become an emerging public health threat. Inhibition of NDM-1 has proven challenging due to its shuttling between pathogenic bacteria. A potent scaffold, diaryl-substituted thiosemicarbazone, was constructed and assayed with metallo-ß-lactamases (MßLs). The obtained twenty-six molecules specifically inhibited NDM-1 with IC50 0.038-34.7 µM range (except 1e, 2e, and 3d), and 1c is the most potent inhibitor (IC50 = 0.038 µM). The structure-activity relationship of synthetic thiosemicarbazones revealed that the diaryl-substitutes, specifically 2-pyridine and 2-hydroxylbenzene improved inhibitory activities of the inhibitors. The thiosemicarbazones exhibited synergistic antimycobacterial actions against E. coli-NDM-1, resulted a 2-512-fold reduction in MIC of meropenem, while 1c restored 16-256-, 16-, and 2-fold activity of the antibiotic on clinical isolates ECs, K. pneumonia and P. aeruginosa harboring NDM-1, respectively. Also, mice experiments showed that 1c had a synergistic antibacterial ability with meropenem, reduced the bacterial load clinical isolate EC08 in the spleen and liver. This work provided a highly promising scaffold for the development of NDM-1 inhibitors.


Assuntos
Antibacterianos/farmacologia , Inibidores Enzimáticos/farmacologia , Tiossemicarbazonas/farmacologia , beta-Lactamases/metabolismo , Antibacterianos/síntese química , Antibacterianos/química , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/química , Escherichia coli/enzimologia , Testes de Sensibilidade Microbiana , Estrutura Molecular , Relação Estrutura-Atividade , Tiossemicarbazonas/síntese química , Tiossemicarbazonas/química
14.
Bioorg Chem ; 112: 104889, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33915460

RESUMO

The emerging COVID-19 pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has raised a global catastrophe. To date, there is no specific antiviral drug available to combat this virus, except the vaccine. In this study, the main protease (Mpro) required for SARS-CoV-2 viral replication was expressed and purified. Thirty-six compounds were tested as inhibitors of SARS-CoV-2 Mpro by fluorescence resonance energy transfer (FRET) technique. The half-maximal inhibitory concentration (IC50) values of Ebselen and Ebsulfur analogs were obtained to be in the range of 0.074-0.91 µM. Notably, the molecules containing furane substituent displayed higher inhibition against Mpro, followed by Ebselen 1i (IC50 = 0.074 µM) and Ebsulfur 2k (IC50 = 0.11 µM). The action mechanism of 1i and 2k were characterized by enzyme kinetics, pre-incubation and jump dilution assays, as well as fluorescent labeling experiments, which suggested that both compounds covalently and irreversibly bind to Mpro, while molecular docking suggested that 2k formed an SS bond with the Cys145 at the enzymatic active site. This study provides two very potent scaffolds Ebsulfur and Ebselen for the development of covalent inhibitors of Mpro to combat COVID-19.


Assuntos
Antivirais/metabolismo , Azóis/metabolismo , Compostos Organosselênicos/metabolismo , SARS-CoV-2/metabolismo , Compostos de Enxofre/metabolismo , Proteínas da Matriz Viral/metabolismo , Antivirais/química , Antivirais/uso terapêutico , Azóis/química , Azóis/uso terapêutico , Sítios de Ligação , COVID-19/patologia , COVID-19/virologia , Domínio Catalítico , Transferência Ressonante de Energia de Fluorescência , Humanos , Concentração Inibidora 50 , Isoindóis , Cinética , Simulação de Acoplamento Molecular , Compostos Organosselênicos/química , Compostos Organosselênicos/uso terapêutico , SARS-CoV-2/isolamento & purificação , Relação Estrutura-Atividade , Compostos de Enxofre/química , Compostos de Enxofre/uso terapêutico , Proteínas da Matriz Viral/antagonistas & inibidores , Proteínas da Matriz Viral/genética , Tratamento Farmacológico da COVID-19
15.
Biol Pharm Bull ; 44(3): 379-388, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33390389

RESUMO

Lipopolysaccharide (LPS)-induced inflammation is the leading cause of multiple organ failure in sepsis. Pyruvate kinase 2 (PKM2) is a protein kinase and transcriptional coactivator that plays an important role in glycolysis. Recent studies have confirmed that glycolysis maintains the M1 differentiation and induces immune activation in macrophages. Lycium barbarum polysaccharide (LBP), the main bioactive component of Chinese wolfberry, suppresses glycolysis and inflammation. Here, RAW264.7 macrophages were treated with LBP for evaluating its effects against LPS-induced inflammation. The differentiation of M1/M2 macrophages was assessed by flow cytometry for assessing the cell surface markers, CD86 and CD206. The enrichment of hypoxia inducible factor (HIF)-1α and ubiquitin in the PKM2 protein complex was determined by co-immunoprecipitation. LBP suppressed LPS-induced glycolysis, differentiation of M1 macrophages, and the production of interleukin (IL)-1ß, tumor necrosis factor (TNF)-α, and high mobility group (HMG) 1 proteins. The suppressive effects of LBP were similar to those of PKM2 knockdown, but were abolished by the overexpression of PKM2. LPS elevated the mRNA and protein levels of PKM2. LBP reduced the LPS-induced expression of PKM2 protein, but had no effects on the expression of PKM2 mRNA. LPS inhibited the ubiquitination of PKM2, probably by downregulating the expression of ubiquitin ligases, including Nedd4L, Nedd4, and Gnb2. LBP interfered with the inhibition of PKM2 ubiquitination by upregulating the expression of Nedd4L, Nedd4, and Gnb2. In conclusion, LBP suppressed the LPS-induced inflammation by altering glycolysis and the M1 differentiation of macrophages. The effects of LBP were mediated by the downregulation of PKM2 via enhanced ubiquitination.


Assuntos
Medicamentos de Ervas Chinesas/farmacologia , Glicólise/efeitos dos fármacos , Piruvato Quinase/metabolismo , Animais , Diferenciação Celular/efeitos dos fármacos , Proteínas de Ligação ao GTP/genética , Proteínas de Ligação ao GTP/metabolismo , Glucose/metabolismo , Inflamação/induzido quimicamente , Inflamação/genética , Inflamação/metabolismo , Ácido Láctico/metabolismo , Lipopolissacarídeos , Camundongos , Ubiquitina-Proteína Ligases Nedd4/genética , Ubiquitina-Proteína Ligases Nedd4/metabolismo , Proteólise/efeitos dos fármacos , Piruvato Quinase/genética , Células RAW 264.7 , Ubiquitinação/efeitos dos fármacos
16.
Int J Cancer ; 147(9): 2503-2514, 2020 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-32428246

RESUMO

Chemotherapy-induced neuropathic pain is a common dose-limiting side effect of cancer treatment but the underlying mechanisms are largely unknown. Here, we used a whole-genome expression microarray and gene ontology analysis to identify the upregulation of a sequence-specific DNA-binding protein, HOXA6, in the spinal dorsal horn on Day 10 after injection of rats with oxaliplatin. Genetic disruption of HOXA6 with siRNAs alleviated mechanical allodynia after oxaliplatin administration. Reduced representation bisulfite sequencing assays indicated that oxaliplatin decreased the methylation levels of the SOX10 promoter but not of HOXA6. TET1 was also upregulated by oxaliplatin. Genetic disruption of TET1 with siRNA blocked the promoter demethylation of SOX10 and the upregulation of HOXA6 and SOX10. Importantly, inhibition of SOX10 by intrathecal application of SOX10 siRNA ameliorated the mechanical allodynia induced by oxaliplatin and downregulated the expression of HOXA6. Consistently, overexpression of SOX10 through intraspinal injection of AAV-SOX10-EGFP produced mechanical allodynia and upregulated the expression of spinal dorsal horn HOXA6. Moreover, chromatin immunoprecipitation assays demonstrated that oxaliplatin increased the binding of SOX10 to the promoter region of HOXA6. Taken together, our data suggest that HOXA6 upregulation through the TET1-mediated promoter demethylation of SOX10 may contribute to oxaliplatin-induced neuropathic pain.


Assuntos
Dioxigenases/metabolismo , Proteínas de Homeodomínio/genética , Neuralgia/genética , Oxaliplatina/efeitos adversos , Fatores de Transcrição SOXE/genética , Animais , Desmetilação do DNA/efeitos dos fármacos , Dioxigenases/genética , Modelos Animais de Doenças , Perfilação da Expressão Gênica , Humanos , Hiperalgesia/induzido quimicamente , Hiperalgesia/genética , Hiperalgesia/patologia , Injeções Espinhais , Masculino , Neuralgia/induzido quimicamente , Neuralgia/patologia , Análise de Sequência com Séries de Oligonucleotídeos , Regiões Promotoras Genéticas/genética , RNA Interferente Pequeno/administração & dosagem , RNA Interferente Pequeno/genética , Ratos , Corno Dorsal da Medula Espinal/efeitos dos fármacos , Corno Dorsal da Medula Espinal/patologia , Regulação para Cima/efeitos dos fármacos
17.
J Antimicrob Chemother ; 75(10): 2773-2779, 2020 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-32747937

RESUMO

BACKGROUND: Bacterial heteroresistance has been increasingly identified as an important phenomenon for many antibiotic/bacterium combinations. OBJECTIVES: To investigate ciprofloxacin heteroresistance in Salmonella and characterize mechanisms contributing to ciprofloxacin heteroresistance. METHODS: Ciprofloxacin-heteroresistant Salmonella were identified by population analysis profiling (PAP). Target mutations and the presence of PMQR genes were detected using PCR and sequencing. Expression of acrB, acrF and qnrS was conducted by quantitative RT-PCR. Competition ability and virulence were also compared using pyrosequencing, blue/white screening, adhesion and invasion assays and a Galleria model. Two subpopulations were whole-genome sequenced using Oxford Nanopore and Illumina platforms. RESULTS: PAP identified one Salmonella from food that yielded a subpopulation demonstrating heteroresistance to ciprofloxacin at a low frequency (10-9 to 10-7). WGS and PFGE analyses confirmed that the two subpopulations were isogenic, with six SNPs and two small deletions distinguishing the resistant from the susceptible. Both subpopulations possessed a T57S substitution in ParC and carried qnrS. The resistant subpopulation was distinguished by overexpression of acrB and acrF, a deletion within rsxC and altered expression of soxS. The resistant population had a competitive advantage against the parental population when grown in the presence of bile salts but was attenuated in the adhesion and invasion of human intestinal cells. CONCLUSIONS: We determined that heteroresistance resulted from a combination of mutations in fluoroquinolone target genes and overexpression of efflux pumps associated with a deletion in rsxC. This study warns that ciprofloxacin heteroresistance exists in Salmonella in the food chain and highlights the necessity for careful interpretation of antibiotic susceptibility.


Assuntos
Antibacterianos , Ciprofloxacina , Farmacorresistência Bacteriana Múltipla , Salmonella enterica , Antibacterianos/farmacologia , Proteínas de Bactérias/genética , Ciprofloxacina/farmacologia , Farmacorresistência Bacteriana/efeitos dos fármacos , Farmacorresistência Bacteriana Múltipla/efeitos dos fármacos , Humanos , Testes de Sensibilidade Microbiana , Salmonella/efeitos dos fármacos , Salmonella enterica/efeitos dos fármacos , Salmonella enterica/genética , Sorogrupo
18.
Int J Neuropsychopharmacol ; 23(4): 257-267, 2020 04 23.
Artigo em Inglês | MEDLINE | ID: mdl-32124922

RESUMO

BACKGROUND: Although the action mechanism of antineoplastic agents is different, oxaliplatin, paclitaxel, or bortezomib as first-line antineoplastic drugs can induce painful neuropathy. In rodents, mechanical allodynia is a common phenotype of painful neuropathy for 3 chemotherapeutics. However, whether there is a common molecular involved in the different chemotherapeutics-induced painful peripheral neuropathy remains unclear. METHODS: Mechanical allodynia was tested by von Frey hairs following i.p. injection of vehicle, oxaliplatin, paclitaxel, or bortezomib in Sprague-Dawley rats. Reduced representation bisulfite sequencing and methylated DNA immunoprecipitation were used to detect the change of DNA methylation. Western blot, quantitative polymerase chain reaction, chromatin immunoprecipitation, and immunohistochemistry were employed to explore the molecular mechanisms. RESULTS: In 3 chemotherapeutic models, oxaliplatin, paclitaxel, or bortezomib accordantly upregulated the expression of transient receptor potential cation channel, subfamily C6 (TRPC6) mRNA and protein without affecting the DNA methylation level of TRPC6 gene in DRG. Inhibition of TRPC6 by using TRPC6 siRNA (i.t., 10 consecutive days) relieved mechanical allodynia significantly following application of chemotherapeutics. Furthermore, the downregulated recruitment of DNA methyltransferase 3 beta (DNMT3b) at paired box protein 6 (PAX6) gene led to the hypomethylation of PAX6 gene and increased PAX6 expression. Finally, the increased PAX6 via binding to the TPRC6 promoter contributes to the TRPC6 increase and mechanical allodynia following chemotherapeutics treatment. CONCLUSIONS: The TRPC6 upregulation through DNMT3b-mediated PAX6 gene hypomethylation participated in mechanical allodynia following application of different chemotherapeutic drugs.


Assuntos
Antineoplásicos/farmacologia , DNA (Citosina-5-)-Metiltransferases/efeitos dos fármacos , Metilação de DNA/efeitos dos fármacos , Gânglios Espinais/efeitos dos fármacos , Expressão Gênica/efeitos dos fármacos , Hiperalgesia/induzido quimicamente , Neuralgia/induzido quimicamente , Fator de Transcrição PAX6/efeitos dos fármacos , Canais de Cátion TRPC/efeitos dos fármacos , Animais , Bortezomib/farmacologia , Modelos Animais de Doenças , Hiperalgesia/tratamento farmacológico , Hiperalgesia/etiologia , Masculino , Neuralgia/complicações , Oxaliplatina/farmacologia , Paclitaxel/farmacologia , Ratos , Ratos Sprague-Dawley , Canais de Cátion TRPC/antagonistas & inibidores , Regulação para Cima/efeitos dos fármacos , DNA Metiltransferase 3B
19.
J Surg Res ; 246: 170-181, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31590030

RESUMO

BACKGROUND: Electroacupuncture has been reported to protect the body from organ damages, but its mechanisms remain to be explored. This research was designed to investigate the function of electroacupuncture in lung injury resulted from hind limb ischemia-reperfusion (LIR) and whether p38 mitogen-activated protein kinase (p38 MAPK)-mediated nuclear factor erythroid-2-related factor-2 (Nrf2)/heme oxygenase (HO)-1 pathway contributes to the protective effect of electroacupuncture on LIR-originated lung damage. MATERIALS AND METHODS: Rabbits were subjected to occluding femoral artery for 2 h. Then they received reperfusion for 4 h to establish lung injury model. Electroacupuncture stimulation was performed bilaterally at Feishu and Zusanli acupoints for 15 min once a day for 5 d before the experiment and throughout the hind LIR model performing in the experimental day. Blood samples and lung tissues were collected to examine the role of electroacupuncture treatment in inflammatory response, oxidative stress, and lung injury. Both the protein expression and the messenger RNA level of Nrf2 and HO-1 were detected. RESULTS: The results showed that electroacupuncture treatment remarkably alleviated lung injury, decreased inflammatory cytokines secretion, attenuated lung oxidative stress, increased the amount of Nrf2 and HO-1, and increased the ratio of phospho-p38 MAPK to p38 MAPK after LIR. However, the protective effects exerted by electroacupuncture were reversed to some extent by the preconditioning with SB203580, a p38 MAPK-specific inhibitor. CONCLUSIONS: These results suggested that electroacupuncture could attenuate lung injury in rabbits subjected to LIR by inhibition of proinflammatory cytokine response and oxidative stress through activating p38 MAPK-mediated Nrf2/HO-1 pathway.


Assuntos
Lesão Pulmonar Aguda/prevenção & controle , Eletroacupuntura , Extremidades/irrigação sanguínea , Sistema de Sinalização das MAP Quinases/imunologia , Traumatismo por Reperfusão/complicações , Lesão Pulmonar Aguda/imunologia , Lesão Pulmonar Aguda/patologia , Animais , Modelos Animais de Doenças , Artéria Femoral/cirurgia , Heme Oxigenase-1/metabolismo , Humanos , Imidazóis/farmacologia , Mediadores da Inflamação/imunologia , Mediadores da Inflamação/metabolismo , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Masculino , Fator 2 Relacionado a NF-E2/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Estresse Oxidativo/imunologia , Piridinas/farmacologia , Coelhos , Traumatismo por Reperfusão/imunologia , Traumatismo por Reperfusão/terapia , Resultado do Tratamento , Proteínas Quinases p38 Ativadas por Mitógeno/antagonistas & inibidores , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
20.
Entropy (Basel) ; 22(7)2020 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-33286490

RESUMO

In this work, the formation of carbide with the concertation of carbon at 0.1 at.% in refractory high-entropy alloy (RHEA) Mo15Nb20Re15Ta30W20 was studied under both ambient and high-pressure high-temperature conditions. The x-ray diffraction of dilute carbon (C)-doped RHEA under ambient pressure showed that the phases and lattice constant of RHEA were not influenced by the addition of 0.1 at.% C. In contrast, C-doped RHEA showed unexpected phase formation and transformation under combined high-pressure and high-temperature conditions by resistively employing the heated diamond anvil cell (DAC) technique. The new FCC_L12 phase appeared at 6 GPa and 809 °C and preserved the ambient temperature and pressure. High-pressure and high-temperature promoted the formation of carbides Ta3C and Nb3C, which are stable and may further improve the mechanical performance of the dilute C-doped alloy Mo15Nb20Re15Ta30W20.

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