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1.
Nat Immunol ; 25(4): 622-632, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38454157

RESUMO

The development of a vaccine specific to severe acute respiratory syndrome coronavirus 2 Omicron has been hampered due to its low immunogenicity. Here, using reverse mutagenesis, we found that a phenylalanine-to-serine mutation at position 375 (F375S) in the spike protein of Omicron to revert it to the sequence found in Delta and other ancestral strains significantly enhanced the immunogenicity of Omicron vaccines. Sequence FAPFFAF at position 371-377 in Omicron spike had a potent inhibitory effect on macrophage uptake of receptor-binding domain (RBD) nanoparticles or spike-pseudovirus particles containing this sequence. Omicron RBD enhanced binding to Siglec-9 on macrophages to impair phagocytosis and antigen presentation and promote immune evasion, which could be abrogated by the F375S mutation. A bivalent F375S Omicron RBD and Delta-RBD nanoparticle vaccine elicited potent and broad nAbs in mice, rabbits and rhesus macaques. Our research suggested that manipulation of the Siglec-9 pathway could be a promising approach to enhance vaccine response.


Assuntos
COVID-19 , SARS-CoV-2 , Animais , Camundongos , Coelhos , Anticorpos Neutralizantes , Anticorpos Antivirais , Macaca mulatta , Macrófagos , Nanovacinas , Fagocitose , Lectinas Semelhantes a Imunoglobulina de Ligação ao Ácido Siálico
2.
Adv Sci (Weinh) ; 10(27): e2301034, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37526323

RESUMO

Because of the rapid mutation and high airborne transmission of SARS-CoV-2, a universal vaccine preventing the infection in the upper respiratory tract is particularly urgent. Here, a mosaic receptor-binding domain (RBD) nanoparticle (NP) vaccine is developed, which induces more RBD-targeted type IV neutralizing antibodies (NAbs) and exhibits broad cross-protective activity against multiple SARS-CoV-2 sublineages including the newly-emerged BF.7, BQ.1, XBB. As several T-cell-reactive epitopes, which are highly conserved in sarbecoviruses, are displayed on the NP surface, it also provokes potent and cross-reactive cellular immune responses in the respiratory tissue. Through intranasal delivery, it elicits robust mucosal immune responses and full protection without any adjuvants. Therefore, this intranasal mosaic NP vaccine can be further developed as a pan-sarbecovirus vaccine to block the viral entrance from the upper respiratory tract.


Assuntos
COVID-19 , Nanopartículas , Vacinas , Humanos , SARS-CoV-2 , COVID-19/prevenção & controle , Imunidade nas Mucosas
4.
Oncogene ; 41(22): 3104-3117, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35468939

RESUMO

Kelch superfamily involves a variety of proteins containing multiple kelch motif and is well characterized as substrate adaptors for CUL3 E3 ligases, which play critical roles in carcinogenesis. However, the role of kelch proteins in lung cancer remains largely unknown. In this study, the non-small cell lung cancer (NSCLC) patients with higher expression of a kelch protein, kelch domain containing 3 (KLHDC3), showed worse overall survival. KLHDC3 deficiency affected NSCLC cell lines proliferation in vitro and in vivo. Further study indicated that KLHDC3 mediated CUL2 E3 ligase and tumor suppressor p14ARF interaction, facilitating the N-terminal ubiquitylation and subsequent degradation of p14ARF. Interestingly, Gefitinib-resistant NSCLC cell lines displayed higher KLHDC3 protein levels. Gefitinib and Osimertinib medications were capable of upregulating KLHDC3 expression to promote p14ARF degradation in the NSCLC cell lines. KLHDC3 shortage significantly increased the sensitivity of lung cancer cells to epidermal growth factor receptor (EGFR)-targeted drugs, providing an alternative explanation for the development of Gefitinib and Osimertinib resistance in NSCLC therapy. Our works suggest that CRL2KLHDC3 could be a valuable target to regulate the abundance of p14ARF and postpone the occurrence of EGFR-targeted drugs resistance.


Assuntos
Antineoplásicos , Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Linhagem Celular Tumoral , Proliferação de Células , Resistencia a Medicamentos Antineoplásicos/genética , Receptores ErbB/genética , Receptores ErbB/metabolismo , Gefitinibe/farmacologia , Gefitinibe/uso terapêutico , Humanos , Repetição Kelch , Neoplasias Pulmonares/metabolismo , Inibidores de Proteínas Quinases/farmacologia , Proteína Supressora de Tumor p14ARF/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitinação
5.
Patient Prefer Adherence ; 16: 635-645, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35283626

RESUMO

Purpose: This study examines the preferences for WeChat-based and hospital-based family intervention among caregivers of people living with schizophrenia (PLS) and identify correlates associated with these preferences. Patients and Methods: A cross-sectional study was conducted with 449 family caregivers of PLS. Face-to-face interviews were conducted to collect information on socio-demographics, preferences for WeChat-based and hospital-based family intervention, social support, and coping. Results: Over 72.16% of participants endorsed hospital-based family intervention, while 50.11% endorsed WeChat-based family intervention. Endorsement of WeChat-based family intervention was associated with younger age (OR=0.42, 95% CI: 0.22, 0.79), WeChat use (OR=12.90, 95% CI: 7.48, 22.23), and higher social support (OR=1.03, 95% CI: 1.01, 1.04). Endorsement of hospital-based family intervention was associated with lower education (OR=0.19-0.37, 95% CI: 0.07, 0.66) and WeChat use (OR=3.27, 95% CI: 1.91, 5.59). Conclusion: The studies showed a higher endorsement rate for hospital-based family intervention than WeChat-based family intervention and provide implications for developing targeted family intervention programs based on participants' own unique characteristics.

6.
Adv Sci (Weinh) ; 9(11): e2105378, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35142444

RESUMO

The SARS-CoV-2 Delta (B.1.617.2) strain is a variant of concern (VOC) that has become the dominant strain worldwide in 2021. Its transmission capacity is approximately twice that of the original strain, with a shorter incubation period and higher viral load during infection. Importantly, the breakthrough infections of the Delta variant have continued to emerge in the first-generation vaccine recipients. There is thus an urgent need to develop a novel vaccine with SARS-CoV-2 variants as the major target. Here, receptor binding domain (RBD)-conjugated nanoparticle vaccines targeting the Delta variant, as well as the early and Beta/Gamma strains, are developed. Under both a single-dose and a prime-boost strategy, these RBD-conjugated nanoparticle vaccines induce the abundant neutralizing antibodies (NAbs) and significantly protect hACE2 mice from infection by the authentic SARS-CoV-2 Delta strain, as well as the early and Beta strains. Furthermore, the elicitation of the robust production of broader cross-protective NAbs against almost all the notable SARS-CoV-2 variants including the Omicron variant in rhesus macaques by the third re-boost with trivalent vaccines is found. These results suggest that RBD-based monovalent or multivalent nanoparticle vaccines provide a promising second-generation vaccine strategy for SARS-CoV-2 variants.


Assuntos
COVID-19 , Nanopartículas , Animais , Anticorpos Amplamente Neutralizantes , COVID-19/prevenção & controle , Macaca mulatta/metabolismo , Camundongos , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus , Vacinas Conjugadas
7.
Cell Rep ; 38(3): 110256, 2022 01 18.
Artigo em Inglês | MEDLINE | ID: mdl-34990583

RESUMO

Inoculation against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is ongoing worldwide. However, the emergence of SARS-CoV-2 variants could cause immune evasion. We developed a bivalent nanoparticle vaccine that displays the receptor binding domains (RBDs) of the D614G and B.1.351 strains. With a prime-boost or a single-dose strategy, this vaccine elicits a robust neutralizing antibody and full protection against infection with the authentic D614G or B.1.351 strain in human angiotensin-converting enzyme 2 transgene mice. Interestingly, 8 months after inoculation with the D614G-specific vaccine, a new boost with this bivalent vaccine potently elicits cross-neutralizing antibodies for SARS-CoV-2 variants in rhesus macaques. We suggest that the D614G/B.1.351 bivalent vaccine could be used as an initial single dose or a sequential enforcement dose to prevent infection with SARS-CoV-2 and its variants.


Assuntos
COVID-19/prevenção & controle , Proteção Cruzada , SARS-CoV-2/imunologia , Vacinas Combinadas/uso terapêutico , Animais , Células CHO , Vacinas contra COVID-19/síntese química , Vacinas contra COVID-19/imunologia , Vacinas contra COVID-19/uso terapêutico , Chlorocebus aethiops , Cricetulus , Proteção Cruzada/imunologia , Feminino , Células HEK293 , Humanos , Macaca mulatta , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Nanopartículas , Vacinação/métodos , Vacinas Combinadas/síntese química , Vacinas Combinadas/imunologia , Células Vero
8.
Signal Transduct Target Ther ; 7(1): 7, 2022 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-34983926

RESUMO

Activation-induced cytidine deaminase (AID) initiates class-switch recombination and somatic hypermutation (SHM) in antibody genes. Protein expression and activity are tightly controlled by various mechanisms. However, it remains unknown whether a signal from the extracellular environment directly affects the AID activity in the nucleus where it works. Here, we demonstrated that a deubiquitinase USP10, which specifically stabilizes nuclear AID protein, can translocate into the nucleus after AKT-mediated phosphorylation at its T674 within the NLS domain. Interestingly, the signals from BCR and TLR1/2 synergistically promoted this phosphorylation. The deficiency of USP10 in B cells significantly decreased AID protein levels, subsequently reducing neutralizing antibody production after immunization with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) or human immunodeficiency virus type 1 (HIV-1) nanoparticle vaccines. Collectively, we demonstrated that USP10 functions as an integrator for both BCR and TLR signals and directly regulates nuclear AID activity. Its manipulation could be used for the development of vaccines and adjuvants.


Assuntos
Vacinas contra a AIDS/imunologia , Fator Ativador de Células B/imunologia , Vacinas contra COVID-19/imunologia , Citidina Desaminase/imunologia , HIV-1/imunologia , Nanopartículas , SARS-CoV-2/imunologia , Transdução de Sinais/imunologia , Ubiquitina Tiolesterase/imunologia , Ubiquitinação/imunologia , Vacinas contra a AIDS/genética , Animais , Fator Ativador de Células B/genética , Vacinas contra COVID-19/genética , Citidina Desaminase/genética , Células HEK293 , HIV-1/genética , Humanos , Camundongos , Camundongos Knockout , SARS-CoV-2/genética , Transdução de Sinais/genética , Ubiquitina Tiolesterase/genética
9.
Nat Prod Res ; 36(15): 3938-3944, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33719794

RESUMO

Two previously undescribed triterpenoids (1-2), along with thirteen known compounds (3-15) were isolated from a CHCl3-soluble extract of the leaves of Cyclocarya paliurus. Their structures were established on the basis of chemical and spectroscopic approaches. These compounds were assessed for their therapeutic effects on diabetic nephropathy (DN)-evoked fibrosis through High-Glucose and transforming growth factor-ß1 (TGF-ß1) challenged HK-2 cells. Among them, compounds 3, 5 and 8 could remarkedly decrease the level of fibronectin to relieve DN with 27.66 ± 2.77%, 6.09 ± 0.57% and 17.74 ± 5.83% inhibition rate at 10 µM, 10 µM and 1 µM, respectively.


Assuntos
Juglandaceae , Triterpenos , Juglandaceae/química , Extratos Vegetais/química , Folhas de Planta/química , Triterpenos/química
10.
Signal Transduct Target Ther ; 6(1): 420, 2021 12 14.
Artigo em Inglês | MEDLINE | ID: mdl-34907154

RESUMO

COVID-19 is identified as a zoonotic disease caused by SARS-CoV-2, which also can cross-transmit to many animals but not mice. Genetic modifications of SARS-CoV-2 or mice enable the mice susceptible to viral infection. Although neither is the natural situation, they are currently utilized to establish mouse infection models. Here we report a direct contact transmission of SARS-CoV-2 variant B.1.351 in wild-type mice. The SARS-CoV-2 (B.1.351) replicated efficiently and induced significant pathological changes in lungs and tracheas, accompanied by elevated proinflammatory cytokines in the lungs and sera. Mechanistically, the receptor-binding domain (RBD) of SARS-CoV-2 (B.1.351) spike protein turned to a high binding affinity to mouse angiotensin-converting enzyme 2 (mACE2), allowing the mice highly susceptible to SARS-CoV-2 (B.1.351) infection. Our work suggests that SARS-CoV-2 (B.1.351) expands the host range and therefore increases its transmission route without adapted mutation. As the wild house mice live with human populations quite closely, this possible transmission route could be potentially risky. In addition, because SARS-CoV-2 (B.1.351) is one of the major epidemic strains and the mACE2 in laboratory-used mice is naturally expressed and regulated, the SARS-CoV-2 (B.1.351)/mice could be a much convenient animal model system to study COVID-19 pathogenesis and evaluate antiviral inhibitors and vaccines.


Assuntos
Enzima de Conversão de Angiotensina 2/genética , COVID-19/transmissão , Interações Hospedeiro-Patógeno/genética , Receptores Virais/genética , SARS-CoV-2/imunologia , Glicoproteína da Espícula de Coronavírus/genética , Enzima de Conversão de Angiotensina 2/imunologia , Animais , COVID-19/imunologia , COVID-19/virologia , Citocinas/genética , Citocinas/imunologia , Modelos Animais de Doenças , Expressão Gênica , Células HEK293 , Interações Hospedeiro-Patógeno/imunologia , Humanos , Pulmão/patologia , Pulmão/virologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Ligação Proteica , Domínios Proteicos , Receptores Virais/imunologia , SARS-CoV-2/classificação , SARS-CoV-2/genética , SARS-CoV-2/patogenicidade , Glicoproteína da Espícula de Coronavírus/imunologia , Replicação Viral
13.
Nanotechnology ; 32(35)2021 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-34034237

RESUMO

Herein, we demonstrate a distinctive energy harvesting method that electricity can be generated from the ionic solution flowing through the interstices between packed three-dimensional graphene powders. A constructed electrokinetic nanogenerator with an effective flow area of ∼0.34 cm2can generate a large current of 91.33 nA under 10-6M NaCl solution with a flow rate of 0.4 ml min-1, corresponding to a maximum power density of 0.45µW m-2. Besides, it shows a good linear relationship between the streaming current and the flow rate, suggesting that it could be used as a self-powered micro-flowmeter. These results provide a convenient way for clean energy harvesting and show a bright future for self-powered systems.

14.
mBio ; 12(1)2021 01 19.
Artigo em Inglês | MEDLINE | ID: mdl-33468688

RESUMO

The etiologic agent of COVID-19 is highly contagious and has caused a severe global pandemic. Until now, there has been no simple and reliable system available in a lower-biosafety-grade laboratory for SARS-CoV-2 virologic research and inhibitor screening. In this study, we reported a replicon system which consists of four plasmids expressing the required segments of SARS-CoV-2. Our study revealed that the features for viral RNA synthesis and responses to antivirus drugs of the replicon are similar to those of wild-type viruses. Further analysis indicated that ORF6 provided potent in trans stimulation of the viral replication. Some viral variations, such as 5'UTR-C241T and ORF8-(T28144C) L84S mutation, also exhibit their different impact upon viral replication. Besides, the screening of clinically used drugs identified that several tyrosine kinase inhibitors and DNA-Top II inhibitors potently inhibit the replicon, as well as authentic SARS-CoV-2 viruses. Collectively, this replicon system provides a biosafety-worry-free platform for studying SARS-CoV-2 virology, monitoring the functional impact of viral mutations, and developing viral inhibitors.IMPORTANCE COVID-19 has caused a severe global pandemic. Until now, there has been no simple and reliable system available in a lower-biosafety-grade laboratory for SARS-CoV-2 virologic research and inhibitor screening. We reported a replicon system which consists of four ordinary plasmids expressing the required segments of SARS-CoV-2. Using the replicon system, we developed three application scenarios: (i) to identify the effects of viral proteins on virus replication, (ii) to identify the effects of mutations on viral replication during viral epidemics, and (iii) to perform high-throughput screening of antiviral drugs. Collectively, this replicon system would be useful for virologists to study SARS-CoV-2 virology, for epidemiologists to monitor virus mutations, and for industry to develop antiviral drugs.


Assuntos
Antivirais/farmacologia , COVID-19/virologia , RNA Viral/biossíntese , Replicon/efeitos dos fármacos , SARS-CoV-2/efeitos dos fármacos , SARS-CoV-2/genética , Avaliação Pré-Clínica de Medicamentos/métodos , Feminino , Engenharia Genética , Células HEK293 , Ensaios de Triagem em Larga Escala , Humanos , Concentração Inibidora 50 , Mutação , Pandemias , RNA Viral/genética , Replicon/genética , SARS-CoV-2/metabolismo , Replicação Viral/efeitos dos fármacos
15.
Immunity ; 53(6): 1315-1330.e9, 2020 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-33275896

RESUMO

Various vaccine strategies have been proposed in response to the global COVID-19 pandemic, each with unique strategies for eliciting immune responses. Here, we developed nanoparticle vaccines by covalently conjugating the self-assembled 24-mer ferritin to the receptor binding domain (RBD) and/or heptad repeat (HR) subunits of the Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) spike (S) protein. Compared to monomer vaccines, nanoparticle vaccines elicited more robust neutralizing antibodies and cellular immune responses. RBD and RBD-HR nanoparticle vaccinated hACE2 transgenic mice vaccinated with RBD and/or RBD-HR nanoparticles exhibited reduced viral load in the lungs after SARS-CoV-2 challenge. RBD-HR nanoparticle vaccines also promoted neutralizing antibodies and cellular immune responses against other coronaviruses. The nanoparticle vaccination of rhesus macaques induced neutralizing antibodies, and T and B cell responses prior to boost immunization; these responses persisted for more than three months. RBD- and HR-based nanoparticles thus present a promising vaccination approach against SARS-CoV-2 and other coronaviruses.


Assuntos
Proteínas de Bactérias/imunologia , Vacinas contra COVID-19/imunologia , COVID-19/imunologia , Ferritinas/imunologia , Helicobacter pylori/metabolismo , Proteínas Recombinantes de Fusão/imunologia , SARS-CoV-2/fisiologia , Glicoproteína da Espícula de Coronavírus/imunologia , Enzima de Conversão de Angiotensina 2/genética , Enzima de Conversão de Angiotensina 2/metabolismo , Animais , Anticorpos Neutralizantes/metabolismo , Anticorpos Antivirais/metabolismo , Proteínas de Bactérias/química , Vacinas contra COVID-19/química , Ferritinas/química , Humanos , Macaca mulatta , Camundongos , Camundongos Endogâmicos BALB C , Nanopartículas/química , Pandemias , Ligação Proteica , Glicoproteína da Espícula de Coronavírus/química , Vacinação
16.
ACS Infect Dis ; 5(2): 239-249, 2019 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-30485737

RESUMO

Respiration is a promising target for the development of new antimycobacterial agents, with a growing number of compounds in clinical development entering this target space. However, more candidate inhibitors are needed to expand the therapeutic options available for drug-resistant Mycobacterium tuberculosis infection. Here, we characterize a putative respiratory complex III (QcrB) inhibitor, TB47: a pyrazolo[1,5- a]pyridine-3-carboxamide. TB47 is active (MIC between 0.016 and 0.500 µg/mL) against a panel of 56 M. tuberculosis clinical isolates, including 37 multi-drug-resistant and two extensively drug-resistant strains. Pharmacokinetic and toxicity studies showed promising profiles, including negligible CYP450 interactions, cytotoxicity, and hERG channel inhibition. Consistent with other reported QcrB inhibitors, TB47 inhibits oxygen consumption only when the alternative oxidase, cytochrome bd, is deleted. A point mutation in the qcrB cd2-loop (H190Y, M. smegmatis numbering) rescues the inhibitory effects of TB47. Metabolomic profiling of TB47-treated M. tuberculosis H37Rv cultures revealed accumulation of steps in the TCA cycle and pentose phosphate pathway that are linked to reducing equivalents, suggesting that TB47 causes metabolic redox stress. In mouse infection models, a TB47 monotherapy was not bactericidal. However, TB47 was strongly synergistic with pyrazinamide and rifampicin, suggesting a promising role in combination therapies. We propose that TB47 is an effective lead compound for the development of novel tuberculosis chemotherapies.


Assuntos
Antituberculosos/farmacologia , Complexo III da Cadeia de Transporte de Elétrons/antagonistas & inibidores , Tuberculose Extensivamente Resistente a Medicamentos/tratamento farmacológico , Mycobacterium tuberculosis/efeitos dos fármacos , Tuberculose Resistente a Múltiplos Medicamentos/tratamento farmacológico , Animais , Antituberculosos/farmacocinética , Feminino , Metabolômica , Camundongos , Camundongos Endogâmicos BALB C , Testes de Sensibilidade Microbiana , Piridinas/farmacologia
17.
Carbohydr Res ; 445: 1-6, 2017 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-28376355

RESUMO

Six new cycloartane triterpenoid saponins, thalisides A-F (1-6), along with four known ones (7-10), were isolated from Thalictrum fortunei. The new structures were elucidated by using spectroscopic data (NMR, IR, UV, and MS). Compounds 1-10 were examined for their in vitro cytotoxicity against two human cancer cell lines (HepG2, A549) and antiviral activity against influenza A virus (H1N1) and found to be inactive.


Assuntos
Saponinas/química , Saponinas/farmacologia , Thalictrum/química , Triterpenos/química , Células A549 , Antineoplásicos/química , Antineoplásicos/isolamento & purificação , Antineoplásicos/farmacologia , Antivirais/química , Antivirais/isolamento & purificação , Antivirais/farmacologia , Células Hep G2 , Humanos , Vírus da Influenza A Subtipo H1N1/efeitos dos fármacos , Saponinas/isolamento & purificação
18.
Eur J Med Chem ; 125: 41-48, 2017 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-27654393

RESUMO

A series of pyrazolo[1,5-a]pyridine-3-carboxamide hybrids were designed and evaluated as novel anti-tubercular agents. The representative hybrid 7 exhibited promising in vitro activity against susceptive strain H37Rv and a panel of drug-resistant Mtb strains with MIC values of 0.006 µg/mL and ranged from 0.003 to 0.014 µg/mL, respectively. More importantly, the hybrid 7 also showed very low cytotoxicity, and could significantly reduce the mycobacterial burden in a mouse model infected with autoluminescent H37Ra strain, which may serve as a lead compound for further development of new anti-tubercular agents.


Assuntos
Antituberculosos/síntese química , Piridinas/farmacologia , Animais , Antituberculosos/farmacologia , Morte Celular/efeitos dos fármacos , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Resistência Microbiana a Medicamentos , Camundongos , Testes de Sensibilidade Microbiana , Mycobacterium tuberculosis/efeitos dos fármacos , Piridinas/síntese química
19.
Bioorg Med Chem Lett ; 26(24): 5916-5919, 2016 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-27839917

RESUMO

A series of biheterocyclic (1H-indole, benzofuran, pyrazolo[1,5-a]pyrimidine, pyrazolo[1,5-a]pyrimidin-5(4H)-one, imidazo[2,1-b]thiazole and pyrazolo[5,1-b]thiazole) derivatives were synthesized and evaluated for their anti-tubercular activities. The imidazo[2,1-b]thiazoles 9a-c and pyrazolo[5,1-b]thiazoles 10a-c exhibited promising anti-tubercular activity in varying degrees. Especially, the 2,6-dimethylpyrazolo[5,1-b]thiazole 10a exhibited strong suppressing function against H37Ra strain with MIC value of 0.03µg/mL. Compound 10a also displayed good pharmacokinetic profiles with oral bioavailability (F) of 41.7% and a half-life of 13.4h. Furthermore, 10a significantly reduced the bacterial burden in an autoluminescent H37Ra infected mouse model, suggesting its promising potential for development of anti-tubercular drugs.


Assuntos
Antituberculosos/farmacologia , Descoberta de Drogas , Mycobacterium tuberculosis/efeitos dos fármacos , Tuberculose/tratamento farmacológico , Administração Oral , Animais , Antituberculosos/administração & dosagem , Antituberculosos/química , Disponibilidade Biológica , Chlorocebus aethiops , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Camundongos , Estrutura Molecular , Ratos , Relação Estrutura-Atividade , Células Vero
20.
J Chromatogr Sci ; 54(6): 1010-5, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27015983

RESUMO

A rapid and validated method using ultra high-performance liquid chromatography coupled with a triple quadrupole mass spectrometry (UHPLC-QQQ MS) was developed for simultaneous determination of four active steroidal saponins, i.e., dichotomin ( 1: ), pennogenin 3-O-α-l-arabinofuranosyl-(1→4)-[α-l-rhamnopyranosyl-(1→2)]-ß-d-glucopyranoside ( 2: ), pennogenin 3-O-α-l-rhamnopyranosyl-(1→2)-[α-l-rhamnopyranosyl-(1→4)-α-l-rhamnopyranosyl-(1→4)]-ß-d-glucopyranoside ( 3: ) and diosgenin 3-O-α-l-rhamnopyranosyl-(1→2)-[α-l-rhamnopyranosyl-(1→4)-α-l-rhamnopyranosyl-(1→4)]-ß-d-glucopyranosidein ( 4: ), in Ypsilandra thibetica Franch. The optimized sample preparation and UHPLC-QQQ MS conditions were chosen for quantitative analysis. The separation was performed on an Agilent Zorbax Eclipse Plus C18 column (2.1 mm × 50 mm, 1.8 µm) with gradient elution of acetonitrile-0.1% formic acid in water. All calibration curves showed good linear regression (r> 0.9985) within the test range. The limits of detection and quantification were in the range of 0.02-4.40 and 0.04-22.0 ng/mL, respectively. The proposed method was applied to analyze two batches of Y. thibetica samples for target compounds within 10 min. This work promoted the quality control method for raw material or preparations of Y. thibetica.


Assuntos
Técnicas de Química Analítica/métodos , Cromatografia Líquida de Alta Pressão , Espectrometria de Massas , Melanthiaceae/química , Saponinas/análise , Limite de Detecção , Tempo
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