RESUMO
We report the supramolecular assembly of artificial metalloenzymes (ArMs), based on the Lactococcal multidrug resistance regulator (LmrR) and an exogeneous copper(II)-phenanthroline complex, in the cytoplasm of E.â coli cells. A combination of catalysis, cell-fractionation, and inhibitor experiments, supplemented with in-cell solid-state NMR spectroscopy, confirmed the in-cell assembly. The ArM-containing whole cells were active in the catalysis of the enantioselective Friedel-Crafts alkylation of indoles and the Diels-Alder reaction of azachalcone with cyclopentadiene. Directed evolution resulted in two different improved mutants for both reactions, LmrR_A92E_M8D and LmrR_A92E_V15A, respectively. The whole-cell ArM system required no engineering of the microbial host, the protein scaffold, or the cofactor to achieve ArM assembly and catalysis. We consider this a key step towards integrating abiological catalysis with biosynthesis to generate a hybrid metabolism.
Assuntos
Cobre/metabolismo , Escherichia coli/metabolismo , Metaloproteínas/metabolismo , Compostos Aza/química , Compostos Aza/metabolismo , Biocatálise , Chalconas/química , Chalconas/metabolismo , Cobre/química , Ciclopentanos/química , Ciclopentanos/metabolismo , Escherichia coli/citologia , Indóis/química , Indóis/metabolismo , Lactococcus/química , Lactococcus/metabolismo , Metaloproteínas/química , Estrutura Molecular , EstereoisomerismoRESUMO
Nitrogen-containing flame retardants have been extensively applied due to their low toxicity and smoke-suppression properties; however, their poor charring ability restricts their applications. Herein, a representative nitrogen-containing flame retardant, polyheptanazine, was investigated. Two novel, cost-effective phosphorus-doped polyheptazine (PCN) and cobalt-anchored PCN (Co@PCN) flame retardants were synthesized via a thermal condensation method. The X-ray photoelectron spectroscopy (XPS) results indicated effective doping of P into triazine. Then, flame-retardant particles were introduced into thermoplastic polyurethane (TPU) using a melt-blending approach. The introduction of 3 wt% PCN and Co@PCN could remarkably suppress peak heat release rate (pHRR) (48.5% and 40.0%), peak smoke production rate (pSPR) (25.5% and 21.8%), and increasing residues (10.18 wt%â17.04 wt% and 14.08 wt%). Improvements in charring stability and flame retardancy were ascribed to the formation of P-N bonds and P=N bonds in triazine rings, which promoted the retention of P in the condensed phase, which produced additional high-quality residues.
Assuntos
Compostos Aza/química , Retardadores de Chama , Heptanos/química , Poliuretanos/química , Cobalto/química , Retardadores de Chama/análise , Nanoestruturas/química , Nanoestruturas/ultraestrutura , Fósforo/química , Pirólise , TemperaturaRESUMO
Boron-dipyrromethene (BODIPY) belongs to a family of organoboron compounds, commercialized as fluorescent dyes by Invitrogen™. As BODIPY derivatives, Aza-boron-dipyrromethene (Aza-BODIPY) dyes display superior spectral performances, such as red-shifted spectra and high molar extinction coefficients, and are considered to be extremely attractive organic materials for various bioapplications. Therefore, scientists from different disciplinary backgrounds would benefit from a review that provides a timely summary and outlook regarding Aza-BODIPY dyes. In this review, we report on the latest advances of Aza-BODIPY dyes, along with the empirical design guidelines and photophysical property manipulation of these dyes. In addition, we will discuss the biological applications of Aza-BODIPY dyes in probing various biological activities, as well as in fluorescence bioimaging/detection, newly-emerging photoacoustic bioimaging/detection, and phototherapy together with future challenges and implications in this field. We aim at providing an insightful design guideline and a clear overview of Aza-BODIPY dyes, which might entice new ideas and directions.
Assuntos
Compostos Aza/química , Compostos de Boro/química , Corantes Fluorescentes/química , Imagem Óptica , Técnicas Fotoacústicas , Compostos de Boro/síntese química , Corantes Fluorescentes/síntese químicaRESUMO
High dose intake of docosahexaenoic acid showed beneficial effects on atopic dermatitis in patients and was found to increase regulatory T cells in mice, but its molecular target has not been identified. Free fatty acid receptor 4 (FFA4, also known as GPR120) is a receptor sensing polyunsaturated long-chain fatty acids including docosahexaenoic acid. In the present study, we examined whether FFA4 acted as a therapeutic target of docosahexaenoic acid for treating atopic dermatitis. Experimental atopic dermatitis was induced in mice by 2,4-dinitrochlorobenzene (DNCB) sensitization on day 0, followed by repeated DNCB challenges from D7 to D48. The mice were treated with a selective agonist compound A (30 mg· kg-1· d-1, ip) from D19 to D48, and sacrificed on D49. We found that DNCB-induced atopic dermatitis-like skin lesions, i.e. hypertrophy and mast cell infiltration in skin tissues, as well as markedly elevated serum IgE levels. Administration of compound A significantly suppressed the atopic responses in ears and lymph nodes, such as hypertrophy and mast cell infiltration in the ears, enlarged sizes of lymph nodes, and elevated serum IgE and levels of cytokines IL-4, IL-13, IL-17, and IFN-γ in ear tissue. The therapeutic effects of compound A were abolished by FFA4 knockout. Similarly, increased CD4+Foxp3+ regulatory T-cell population in lymph nodes was observed in wide-type mice treated with compound A, but not seen in FFA4-deficient mice. In conclusion, we demonstrate that activation of FFA4 ameliorates atopic dermatitis by increasing CD4+Foxp3+ regulatory T cells, suggesting FFA4 as a therapeutic target for atopic dermatitis.
Assuntos
Ácido Acético/uso terapêutico , Compostos Aza/uso terapêutico , Dermatite Atópica/tratamento farmacológico , Receptores Acoplados a Proteínas G/agonistas , Linfócitos T Reguladores/metabolismo , Animais , Dermatite Atópica/induzido quimicamente , Dermatite Atópica/patologia , Dinitroclorobenzeno , Orelha/patologia , Técnicas de Inativação de Genes , Linfonodos/efeitos dos fármacos , Linfonodos/patologia , Masculino , Camundongos Endogâmicos BALB C , Camundongos Knockout , Receptores Acoplados a Proteínas G/genéticaRESUMO
Herbs may contain pesticide residues which are an important discriminator of food security and food quality. The challenge of the research was to assess the fate of the herbicide clethodim (CLE) and the insecticide spirotetramat (SPI) applied in herbs (BBCH 11-21) during herb growth and processing under controlled greenhouse trial conditions. The metabolic profile of CLE and SPI and their degradation products in basil (Ocimum basilicum L.), peppermint (Mentha × piperita L.) and sage (Salvia officinalis L.) was also presented. The half-lives of CLE and SPI in herbs were 1.10-1.56 days and 0.51-0.83 days, respectively. The terminal residues of SPI (SPI-enol, SPI-ketohydroxy, SPI-monohydroxy and SPI-enol-glucoside) and CLE (CLE-sulfone and CLE-sulfoxide) in herbal matrices were measured below EU maximum residue limits. In this paper, we aimed to assess the impact of washing and dehydratation pretreatment and calculated processing factors (PFs) which can be applied to more accurate food safety assessments. The PF values of CLE and SPI after drying prior washing was below 1 indicating reduction of initial residues. Drying process without washing demonstrated increases of SPI concentrations (PF up to 1.50). The lowest PFs were obtained when raw herbal plants were washed before drying showing almost complete degradation of parent compound (93-99%).
Assuntos
Compostos Aza/farmacologia , Cicloexanonas/farmacologia , Inseticidas/farmacologia , Metaboloma/efeitos dos fármacos , Desenvolvimento Vegetal/efeitos dos fármacos , Plantas Medicinais/efeitos dos fármacos , Plantas Medicinais/metabolismo , Compostos de Espiro/farmacologia , Cromatografia Líquida , Meio Ambiente , Metabolômica/métodos , Plantas Medicinais/crescimento & desenvolvimento , Reprodutibilidade dos Testes , Espectrometria de Massas em TandemRESUMO
ω3-polyunsaturated free fatty acids (ω3-PUFAs), particularly docosahexaenoic (DHA) and eicosapentaenoic acid (EPA), are thought to exert health promoting effects in metabolic and in inflammatory diseases. The molecular mechanisms of these beneficial effects are only partially understood. DHA and EPA activate Free Fatty Acid receptor 4 (GPR120/FFA4). Recently, the first orally available, synthetic ligand of FFA4, 3-[2-chloro-5-(trifluoromethoxy)phenyl]-3-azaspiro[5.5]undecane-9-acetic acid ("compound A"; cpd A) has been developed. Cpd A exhibits distinctly higher potency, efficiency, and selectivity at FFA4 than ω3-PUFAs and ameliorates insulin resistance and adipose tissue inflammation in the mouse. With GPR120/FFA4 activation believed to also attenuate tissue inflammation in autoimmune diseases, cpd A may also have a beneficial effect in these diseases. We have therefore addressed the therapeutic potential of cpd A in mouse models of three prototypical autoimmune diseases, specifically psoriasis, rheumatoid arthritis, and bullous pemphigoid. The effect of cpd A on the course of Aldara™-induced psoriasis-like dermatitis, K/BxN serum transfer arthritis, and antibody transfer pemphigoid disease-like dermatitis was scrutinized. Cpd A did not alter the course of Aldara-induced psoriasis-like dermatitis, K/BxN serum transfer arthritis, or antibody transfer pemphigoid disease-like dermatitis. Our results suggest that therapeutic regimens solely relying on FFA4 activation do not bear the potential to treat inflammatory diseases. With cpd A distinctly more potent in activating GPR120/FFA4 than ω3-PUFAs, this also suggests that GPR120/FFA4 activation by ω3-PUFAs does not significantly contribute to the health-promoting effects of ω3-PUFAs in autoimmune diseases.
Assuntos
Ácido Acético/administração & dosagem , Anti-Inflamatórios não Esteroides/administração & dosagem , Artrite Reumatoide/tratamento farmacológico , Compostos Aza/administração & dosagem , Penfigoide Bolhoso/tratamento farmacológico , Psoríase/tratamento farmacológico , Receptores Acoplados a Proteínas G/agonistas , Ácido Acético/uso terapêutico , Administração Oral , Animais , Anti-Inflamatórios não Esteroides/uso terapêutico , Artrite Reumatoide/imunologia , Compostos Aza/uso terapêutico , Modelos Animais de Doenças , Ácidos Graxos Ômega-3/metabolismo , Humanos , Imiquimode/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Penfigoide Bolhoso/imunologia , Psoríase/imunologia , Receptores Acoplados a Proteínas G/imunologia , Receptores Acoplados a Proteínas G/metabolismo , Resultado do TratamentoRESUMO
BACKGROUND: There has been renewal of interest in the use of prophylactic antibiotics to reduce the frequency of exacerbations and improve quality of life in chronic obstructive pulmonary disease (COPD). OBJECTIVES: To determine whether or not regular (continuous, intermittent or pulsed) treatment of COPD patients with prophylactic antibiotics reduces exacerbations or affects quality of life. SEARCH METHODS: We searched the Cochrane Airways Group Trials Register and bibliographies of relevant studies. The latest literature search was performed on 27 July 2018. SELECTION CRITERIA: Randomised controlled trials (RCTs) that compared prophylactic antibiotics with placebo in patients with COPD. DATA COLLECTION AND ANALYSIS: We used the standard Cochrane methods. Two independent review authors selected studies for inclusion, extracted data, and assessed risk of bias. We resolved discrepancies by involving a third review author. MAIN RESULTS: We included 14 studies involving 3932 participants in this review. We identified two further studies meeting inclusion criteria but both were terminated early without providing results. All studies were published between 2001 and 2015. Nine studies were of continuous macrolide antibiotics, two studies were of intermittent antibiotic prophylaxis (three times per week) and two were of pulsed antibiotic regimens (e.g. five days every eight weeks). The final study included one continuous, one intermittent and one pulsed arm. The antibiotics investigated were azithromycin, erythromycin, clarithromycin, doxycyline, roxithromycin and moxifloxacin. The study duration varied from three months to 36 months and all used intention-to-treat analysis. Most of the pooled results were of moderate quality. The risk of bias of the included studies was generally low.The studies recruited participants with a mean age between 65 and 72 years and mostly at least moderate-severity COPD. Five studies only included participants with frequent exacerbations and two studies recruited participants requiring systemic steroids or antibiotics or both, or who were at the end stage of their disease and required oxygen. One study recruited participants with pulmonary hypertension secondary to COPD and a further study was specifically designed to asses whether eradication of Chlamydia pneumoniae reduced exacerbation rates.The co-primary outcomes for this review were the number of exacerbations and quality of life.With use of prophylactic antibiotics, the number of participants experiencing one or more exacerbations was reduced (odds ratio (OR) 0.57, 95% CI 0.42 to 0.78; participants = 2716; studies = 8; moderate-quality evidence). This represented a reduction from 61% of participants in the control group compared to 47% in the treatment group (95% CI 39% to 55%). The number needed to treat for an additional beneficial outcome with prophylactic antibiotics given for three to 12 months to prevent one person from experiencing an exacerbation (NNTB) was 8 (95% CI 5 to 17). The test for subgroup difference suggested that continuous and intermittent antibiotics may be more effective than pulsed antibiotics (P = 0.02, I² = 73.3%).The frequency of exacerbations per patient per year was also reduced with prophylactic antibiotic treatment (rate ratio 0.67; 95% CI 0.54 to 0.83; participants = 1384; studies = 5; moderate-quality evidence). Although we were unable to pool the result, six of the seven studies reporting time to first exacerbation identified an increase (i.e. benefit) with antibiotics, which was reported as statistically significant in four studies.There was a statistically significant improvement in quality of life as measured by the St George's Respiratory Questionnaire (SGRQ) with prophylactic antibiotic treatment, but this was smaller than the four unit improvement that is regarded as being clinically significant (mean difference (MD) -1.94, 95% CI -3.13 to -0.75; participants = 2237; studies = 7, high-quality evidence).Prophylactic antibiotics showed no significant effect on the secondary outcomes of frequency of hospital admissions, change in forced expiratory volume in one second (FEV1), serious adverse events or all-cause mortality (moderate-quality evidence). There was some evidence of benefit in exercise tolerance, but this was driven by a single study of lower methodological quality.The adverse events that were recorded varied among the studies depending on the antibiotics used. Azithromycin was associated with significant hearing loss in the treatment group, which was in many cases reversible or partially reversible. The moxifloxacin pulsed study reported a significantly higher number of adverse events in the treatment arm due to the marked increase in gastrointestinal adverse events (P < 0.001). Some adverse events that led to drug discontinuation, such as development of long QTc or tinnitus, were not significantly more frequent in the treatment group than the placebo group but pose important considerations in clinical practice.The development of antibiotic resistance in the community is of major concern. Six studies reported on this, but we were unable to combine results. One study found newly colonised participants to have higher rates of antibiotic resistance. Participants colonised with moxifloxacin-sensitive pseudomonas at initiation of therapy rapidly became resistant with the quinolone treatment. A further study with three active treatment arms found an increase in the degree of antibiotic resistance of isolates in all three arms after 13 weeks treatment. AUTHORS' CONCLUSIONS: Use of continuous and intermittent prophylactic antibiotics results in a clinically significant benefit in reducing exacerbations in COPD patients. All studies of continuous and intermittent antibiotics used macrolides, hence the noted benefit applies only to the use of macrolide antibiotics prescribed at least three times per week. The impact of pulsed antibiotics remains uncertain and requires further research.The studies in this review included mostly participants who were frequent exacerbators with at least moderate-severity COPD. There were also older individuals with a mean age over 65 years. The results of these studies apply only to the group of participants who were studied in these studies and may not be generalisable to other groups.Because of concerns about antibiotic resistance and specific adverse effects, consideration of prophylactic antibiotic use should be mindful of the balance between benefits to individual patients and the potential harms to society created by antibiotic overuse. Monitoring of significant side effects including hearing loss, tinnitus, and long QTc in the community in this elderly patient group may require extra health resources.
Assuntos
Antibacterianos/uso terapêutico , Antibioticoprofilaxia/métodos , Progressão da Doença , Doença Pulmonar Obstrutiva Crônica/tratamento farmacológico , Qualidade de Vida , Idoso , Amoxicilina/efeitos adversos , Amoxicilina/uso terapêutico , Antibacterianos/efeitos adversos , Compostos Aza/uso terapêutico , Azitromicina/efeitos adversos , Azitromicina/uso terapêutico , Claritromicina/uso terapêutico , Ácido Clavulânico/efeitos adversos , Ácido Clavulânico/uso terapêutico , Esquema de Medicação , Eritromicina/uso terapêutico , Fluoroquinolonas , Humanos , Moxifloxacina/uso terapêutico , Quinolinas/uso terapêutico , Ensaios Clínicos Controlados Aleatórios como Assunto , Roxitromicina/efeitos adversos , Roxitromicina/uso terapêutico , Combinação Trimetoprima e Sulfametoxazol/efeitos adversos , Combinação Trimetoprima e Sulfametoxazol/uso terapêuticoRESUMO
The nuclear factor-κB (NF-κB) plays an important role in inflammatory and immune responses. Aberrant NF-κB signaling is implicated in multiple disorders, including cancer. Targeting the regulatory scaffold subunit IκB kinase γ (IKKγ/NEMO) as therapeutic interventions could be promising due to its specific involvement in canonical NF-κB activation without interfering with non-canonical signaling. In this study, the use of unnatural amino acid substituted IKKß with unique photophysical activity to sense water environment changes upon interaction with NEMO provides a powerful in vitro screening platform that would greatly facilitate the identification of compounds having the potential to disrupt IKKß-NEMO interaction, and thus specifically modulate the canonical NF-κB pathway. We then utilized a competitive binding platform to screen the binding ability of a number of potential molecules being synthesized. Our results suggest that a lead compound (-)-PDC-099 is a potent agent with ascertained potency to disrupt IKKß-NEMO complex for modulating NF-κB canonical pathway.
Assuntos
Avaliação Pré-Clínica de Medicamentos/métodos , Corantes Fluorescentes/química , Quinase I-kappa B/metabolismo , Peptídeos/química , Mapas de Interação de Proteínas/efeitos dos fármacos , Triptofano/análogos & derivados , Compostos Aza/química , Compostos Aza/metabolismo , Corantes Fluorescentes/metabolismo , Humanos , Quinase I-kappa B/antagonistas & inibidores , Quinase I-kappa B/química , Modelos Moleculares , Peptídeos/metabolismo , Triptofano/metabolismoRESUMO
The need for better imaging assisted cancer therapy calls for new biocompatible agents with excellent imaging and therapeutic capabilities. This study successfully fabricates albumin-cooperated human serum albumin (HSA)-GGD-ICG nanoparticles (NPs), which are comprised of a magnetic resonance (MR) contrast agent, glycyrrhetinic-acid-modified gadolinium (III)-1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetate (GGD), and a fluorescence (FL) dye, indocyanine green (ICG), for multimodal MR/FL imaging assisted cancer therapy. These HSA-GGD-ICG NPs with excellent biocompatibility are stable under physiological conditions, and exhibit enhanced T1 contrast capability and improved fluorescence imaging capacity. In vitro experiments reveal an apparent effect of the NPs in killing tumor cells under low laser irradiation, due to the enhanced photothermal conversion efficiency (≈85.1%). Importantly, multimodal MR/FL imaging clearly shows the in vivo behaviors and the efficiency of tumor accumulation of HSA-GGD-ICG NPs, as confirmed by a pharmacokinetic study. With the guidance of multimodal imaging, photothermal therapy is subsequently conducted, which demonstrates again high photothermal conversion capability for eliminating tumors without relapse. Notably, real-time monitoring of tumor ablation for prognosis and therapy evaluation is also achieved by MR imaging. This strategy of constructing nanoplatforms through albumin-mediated methods is both convenient and efficient, which would enlighten the design of multimodal imaging assisted cancer therapy for potential clinical translation.
Assuntos
Materiais Biocompatíveis/química , Hipertermia Induzida , Imageamento por Ressonância Magnética , Nanopartículas/química , Imagem Óptica , Fototerapia , Animais , Compostos Aza/química , Linhagem Celular Tumoral , Terapia Combinada , Compostos Heterocíclicos com 1 Anel/química , Verde de Indocianina/química , Camundongos , Nanopartículas/ultraestrutura , Imagens de Fantasmas , Prognóstico , Albumina Sérica Humana/química , TemperaturaRESUMO
Distribution of homogeneous fingermarks in blood is essential for conducting proficiency tests in forensic science. Hence, the artificial blood was prepared using the root nodule extract of Glycine max plants. The reactivity of the artificial blood with widely used human blood detection reagents was tested. Artificial latent fingermarks in blood were printed using an inkjet cartridge case filled with artificial blood solution. The artificial latent fingermarks in blood were developed with amino acid-sensitive reagents and could obtain development as prominent as the image of the master fingermark saved on the computer. Therefore, it has been confirmed that the extract of legume root nodules can be used as artificial blood, and the artificial blood can be used for the preparation of artificial latent fingermarks or footmarks in blood.
Assuntos
Substitutos Sanguíneos , Dermatoglifia , Fabaceae/química , Extratos Vegetais/química , Raízes de Plantas/química , Compostos Aza , Corantes , Ciências Forenses , Humanos , Indanos , Indicadores e Reagentes , Leghemoglobina , Ninidrina , FenolftaleínaRESUMO
Cough is the most common reason to visit a primary care physician, yet it remains an unmet medical need. Fatty acid amide hydrolase (FAAH) is an enzyme that breaks down endocannabinoids, and inhibition of FAAH produces analgesic and anti-inflammatory effects. Cannabinoids inhibit vagal sensory nerve activation and the cough reflex, so it was hypothesised that FAAH inhibition would produce antitussive activity via elevation of endocannabinoids.Primary vagal ganglia neurons, tissue bioassay, in vivo electrophysiology and a conscious guinea pig cough model were utilised to investigate a role for fatty acid amides in modulating sensory nerve activation in vagal afferents.FAAH inhibition produced antitussive activity in guinea pigs with concomitant plasma elevation of the fatty acid amides N-arachidonoylethanolamide (anandamide), palmitoylethanolamide, N-oleoylethanolamide and linoleoylethanolamide. Palmitoylethanolamide inhibited tussive stimulus-induced activation of guinea pig airway innervating vagal ganglia neurons, depolarisation of guinea pig and human vagus, and firing of C-fibre afferents. These effects were mediated via a cannabinoid CB2/Gi/o-coupled pathway and activation of protein phosphatase 2A, resulting in increased calcium sensitivity of calcium-activated potassium channels.These findings identify FAAH inhibition as a target for the development of novel, antitussive agents without the undesirable side-effects of direct cannabinoid receptor agonists.
Assuntos
Amidoidrolases/antagonistas & inibidores , Antitussígenos/uso terapêutico , Capsaicina/farmacologia , Tosse/tratamento farmacológico , Inibidores Enzimáticos/uso terapêutico , Compostos de Espiro/farmacologia , Adulto , Idoso , Animais , Compostos Aza/farmacologia , Moduladores de Receptores de Canabinoides/farmacologia , Canabinoides/antagonistas & inibidores , Feminino , Cobaias , Humanos , Masculino , Pessoa de Meia-Idade , Receptor CB2 de Canabinoide/efeitos dos fármacos , Nervo Vago/efeitos dos fármacosRESUMO
The influence of perspective anti-migraine drug tropoxin on the content of monoamines and related metabolites in Wistar rat brain structures, including frontal cortex (FC), hypothalamus, nucleus accumbens (NA), striatum, and hippocampus, has been studied using HPLC/ED technique. Tropoxin (10 mg/kg) induced a 30% decrease (p < 0.05) in dopamine (DA) level in FC as well as norepinephrine content in NA, while the concentrations of DA metabolites DOPAC and HVA in the hypothalamus were found to increase. The injection of tropoxin in a dose of 20 mg/kg led to an increase in HVA level in hypothalamus as well as seroto- nin metabolite 5-HIAA content in NA. The obtained data provide evidence that tropoxin predominantly influenced the activity of dopaminergic system while the drug effects on the parameters of serotoninergic link seem to be rather mild.
Assuntos
Compostos Aza/farmacologia , Compostos Bicíclicos Heterocíclicos com Pontes/farmacologia , Dopamina/metabolismo , Hipotálamo/metabolismo , Norepinefrina/metabolismo , Animais , Ratos , Ratos WistarRESUMO
BACKGROUND: Cleistopholine is a natural alkaloid present in plants with numerous biological activities. However, cleistopholine has yet to be isolated using modern techniques and the mechanism by which this alkaloid induces apoptosis in cancer cells remains to be elucidated. HYPOTHESIS/PURPOSE: This study aims to isolate cleistopholine from the roots of Enicosanthellum pulchrum by using preparative-HPLC technique and explore the mechanism by which this alkaloid induces apoptosis in human ovarian cancer (CAOV-3) cells in vitro from 24 to 72 h. This compound may be developed as an anticancer agent that induces apoptosis in ovarian cancer cells. STUDY DESIGN/METHODS: Cytotoxicity was assessed via the cell viability assay and changes in cell morphology were observed via the acridine orange/propidium iodide (AO/PI) assay. The involvement of apoptotic pathways was evaluated through caspase analysis and multiple cytotoxicity assays. Meanwhile, early and late apoptotic events via the Annexin V-FITC and DNA laddering assays, respectively. The mechanism of apoptosis was explored at the molecular level by evaluating the expression of specific genes and proteins. In addition, the proliferation of CAOV-3-cells treated with cleistopholine was analysed using the cell cycle arrest assay. RESULTS: The IC50 of cleistopholine (61.4 µM) was comparable with that of the positive control cisplatin (62.8 µM) at 24 h of treatment. Apoptos is was evidenced by cell membrane blebbing, chromatin compression and formation of apoptotic bodies. The initial phase of apoptosis was detected at 24 h by the increase in Annexin V-FITC binding to cell membranes. A DNA ladder was formed at 48 h, indicating DNA fragmentation in the final phase of apoptosis. The mitochondria participated in the process by stimulating the intrinsic pathway via caspase 9 with a reduction in mitochondrial membrane potential (MMP) and an increase in cytochrome c release. Cell death was further validated through the mRNA and protein overexpression of Bax, caspase 3 and caspase 9 in the treated cells compared with the untreated cells. In contrast, Bcl-2, Hsp70 and survivin decreased in expression upon cleistopholine treatment. Cell cycle was arrested at the G0/G1 phase and cell population percentage significantly increased to 43.5%, 45.4% and 54.3% in time-dependent manner in the cleistopholine-treated CAOV-3 cells compared with the untreated cells at 24, 48 and 72 h respectively. CONCLUSION: The current study indicated that cleistopholine can be a potential candidate as a new drug to treat ovarian cancer disease.
Assuntos
Annonaceae/química , Antraquinonas/farmacologia , Antineoplásicos Fitogênicos/farmacologia , Apoptose/efeitos dos fármacos , Compostos Aza/farmacologia , Neoplasias Ovarianas/metabolismo , Extratos Vegetais/farmacologia , Inibidores da Angiogênese/farmacologia , Inibidores da Angiogênese/uso terapêutico , Anexina A5/metabolismo , Antraquinonas/isolamento & purificação , Antraquinonas/uso terapêutico , Antineoplásicos Fitogênicos/uso terapêutico , Compostos Aza/isolamento & purificação , Compostos Aza/uso terapêutico , Caspase 9/metabolismo , Caspases/metabolismo , Ciclo Celular/efeitos dos fármacos , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células , Citocromos c/metabolismo , Fragmentação do DNA , Feminino , Humanos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Neoplasias Ovarianas/tratamento farmacológico , Fitoterapia , Extratos Vegetais/uso terapêutico , Raízes de PlantasRESUMO
CD4+ T-helper cells that produce interleukin-17 (Th17 cells) are characterized as pathological T-helper cells in autoimmune diseases. Differentiation of human and mouse Th17 cells requires a key transcription regulator, retinoic acid receptor-related orphan receptor γt (RORγt), which is a potential therapeutic target for autoimmune diseases. To develop a therapeutic agent for Th17-mediated autoimmune diseases, we have established a high-throughput screening (HTS) assay for candidate screening, in which the luciferase activity in RORγt-LBD positive and negative Jurkat cells were analyzed to evaluate induction of RORγt activity by compounds. This technique was applied to screen a commercially-available drug-like chemical compound library (Enamine) which contains 20155 compounds. The screening identified 17 compounds that can inhibit RORγt function in the HTS screen system. Of these, three tetraazacyclic compounds can potently inhibit RORγt activity, and suppress Th17 differentiation and IL-17 production. These three candidate compounds could significantly attenuate the expression of the Il17a by 65%- 90%, and inhibit IL-17A secretion by 47%, 63%, and 74%, respectively. These compounds also exhibited a potent anti-RORγt activity, with EC50 values of 0.25 µM, 0.67 µM and 2.6 µM, respectively. Our data demonstrated the feasibility of targeting the RORγt to inhibit Th17 cell differentiation and function with these tetraazacyclic compounds, and the potential to improve the structure of these compounds for autoimmune diseases therapeutics.
Assuntos
Compostos Aza/farmacologia , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/antagonistas & inibidores , Bibliotecas de Moléculas Pequenas/farmacologia , Células Th17/efeitos dos fármacos , Animais , Doenças Autoimunes/tratamento farmacológico , Doenças Autoimunes/imunologia , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Avaliação Pré-Clínica de Medicamentos , Células HEK293 , Ensaios de Triagem em Larga Escala , Humanos , Interleucina-17/metabolismo , Células Jurkat , Camundongos , Bibliotecas de Moléculas Pequenas/química , Células Th17/citologiaRESUMO
Through antigenic drift and shifts, influenza virus infections continue to be an annual cause of morbidity in healthy populations and of death among elderly and at-risk patients. The emergence of highly pathogenic avian influenza viruses such as H5N1 and H7N9 and the rapid spread of the swine-origin H1N1 influenza virus in 2009 demonstrate the continued need for effective therapeutic agents for influenza. While several neuraminidase inhibitors have been developed for the treatment of influenza virus infections, these have shown a limited window for treatment initiation, and resistant variants have been noted in the population. In addition, an older class of antiviral drugs for influenza, the adamantanes, are no longer recommended for treatment due to widespread resistance. There remains a need for new influenza therapeutic agents with improved efficacy as well as an expanded window for the initiation of treatment. Azaindole compounds targeting the influenza A virus PB2 protein and demonstrating excellent in vitro and in vivo properties have been identified. To evaluate the in vivo efficacy of these PB2 inhibitors, we utilized a mouse influenza A virus infection model. In addition to traditional endpoints, i.e., death, morbidity, and body weight loss, we measured lung function using whole-body plethysmography, and we used these data to develop a composite efficacy score that takes compound exposure into account. This model allowed the rapid identification and ranking of molecules relative to each other and to oseltamivir. The ability to identify compounds with enhanced preclinical properties provides an opportunity to develop more-effective treatments for influenza in patients.
Assuntos
Antivirais/farmacologia , Compostos Aza/farmacologia , Indóis/farmacologia , Vírus da Influenza A Subtipo H1N1/efeitos dos fármacos , Infecções por Orthomyxoviridae/tratamento farmacológico , Projetos de Pesquisa , Proteínas Virais/antagonistas & inibidores , Animais , Antivirais/síntese química , Antivirais/farmacocinética , Compostos Aza/síntese química , Compostos Aza/farmacocinética , Avaliação Pré-Clínica de Medicamentos , Farmacorresistência Viral , Expressão Gênica , Indóis/síntese química , Indóis/farmacocinética , Vírus da Influenza A Subtipo H1N1/genética , Vírus da Influenza A Subtipo H1N1/metabolismo , Pulmão/efeitos dos fármacos , Pulmão/metabolismo , Pulmão/patologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Infecções por Orthomyxoviridae/mortalidade , Infecções por Orthomyxoviridae/patologia , Infecções por Orthomyxoviridae/virologia , Oseltamivir/farmacologia , Testes de Função Respiratória , Análise de Sobrevida , Proteínas Virais/genética , Proteínas Virais/metabolismoRESUMO
The aim of this study was to evaluate the potential toxicity of spirotetramat to the earthworm Eisenia fetida in a natural soil environment. Many biochemical markers, viz., superoxide dismutase (SOD), catalase (CAT), peroxidase (POD), glutathione S-transferase (GST), cellulase, and malondialdehyde (MDA) contents were measured after exposure to 0.25, 1.25, and 2.5mgkg(-1) for 2, 7, 14, 21, and 28days. In addition, the comet assay was performed on earthworm coelomocytes to assess the level of genetic damage. The results demonstrate that the SOD activity and MDA content were significantly stimulated by the highest dose (2.5mgkg(-1)) of spirotetramat for the entire period of exposure. The activities of CAT and POD increased significantly by 2d and 21d, respectively, but the activities of both were significantly inhibited after prolonged exposure (28d). After an initial increase on the 2nd day, the cellulase activity in the high-dose treatment group was significantly inhibited for the entire remaining exposure period. The comet assay results demonstrate that spirotetramat (⩽2.5mgkg(-1)) can induce low and intermediate degrees of DNA damage in earthworm coelomocytes. The results indicate that spirotetramat may pose potential biochemical and genetic toxicity to earthworms (E. fetida), and this information is helpful for understanding the ecological toxicity of spirotetramat on soil invertebrate organisms.
Assuntos
Compostos Aza/toxicidade , Dano ao DNA , Monitoramento Ambiental/métodos , Oligoquetos/efeitos dos fármacos , Poluentes do Solo/toxicidade , Solo/química , Compostos de Espiro/toxicidade , Animais , Compostos Aza/análise , Biomarcadores/análise , Catalase/metabolismo , Ensaio Cometa , Glutationa Transferase/metabolismo , Malondialdeído/metabolismo , Oligoquetos/enzimologia , Oligoquetos/genética , Peroxidase/metabolismo , Solo/normas , Poluentes do Solo/análise , Compostos de Espiro/análise , Superóxido Dismutase/metabolismoRESUMO
Novel 4'-substituted ß-d-2'-deoxy-2'-α-fluoro (2'd2'F) nucleoside inhibitors of respiratory syncytial virus (RSV) are reported. The introduction of 4'-substitution onto 2'd2'F nucleoside analogs resulted in compounds demonstrating potent cell based RSV inhibition, improved inhibition of the RSV polymerase by the nucleoside triphosphate metabolites, and enhanced selectivity over incorporation by mitochondrial RNA and DNA polymerases. Selectivity over the mitochondrial polymerases was found to be extremely sensitive to the specific 4'-substitution and not readily predictable. Combining the most potent and selective 4'-groups from N-nucleoside analogs onto a 2'd2'F C-nucleoside analog resulted in the identification of ß-D-2'-deoxy-2'-α-fluoro-4'-α-cyano-5-aza-7,9-dideaza adenosine as a promising nucleoside lead for RSV.
Assuntos
Adenosina/química , Antivirais/química , DNA Polimerase Dirigida por DNA/química , Inibidores da Síntese de Ácido Nucleico/química , RNA Polimerase Dependente de RNA/antagonistas & inibidores , RNA/química , Vírus Sinciciais Respiratórios/enzimologia , Vírus Sinciciais Respiratórios/fisiologia , Adenosina/síntese química , Adenosina/farmacologia , Antivirais/síntese química , Antivirais/farmacologia , Compostos Aza/química , DNA Polimerase Dirigida por DNA/metabolismo , Avaliação Pré-Clínica de Medicamentos , Inibidores da Síntese de Ácido Nucleico/síntese química , Inibidores da Síntese de Ácido Nucleico/farmacologia , RNA/metabolismo , RNA Mitocondrial , RNA Polimerase Dependente de RNA/metabolismo , Vírus Sinciciais Respiratórios/efeitos dos fármacos , Relação Estrutura-Atividade , Replicação Viral/efeitos dos fármacosRESUMO
Synthesis and SAR of a series of 7-azaindoles as Orai channel inhibitors showing good potency inhibiting IL-2 production in Jurkat cells is described. Compound 14d displaying best pharmacokinetic properties was further characterized in a model of allergen induced asthma showing inhibition in the number of eosinophils in BALF. High lipophilicity remains as one of the main challenges for this class of compounds.
Assuntos
Bloqueadores dos Canais de Cálcio/química , Canais de Cálcio/química , Indóis/química , Piridinas/química , Pirróis/química , Animais , Asma , Compostos Aza/química , Bloqueadores dos Canais de Cálcio/farmacocinética , Bloqueadores dos Canais de Cálcio/uso terapêutico , Canais de Cálcio/metabolismo , Modelos Animais de Doenças , Avaliação Pré-Clínica de Medicamentos , Meia-Vida , Humanos , Hipersensibilidade/tratamento farmacológico , Hipersensibilidade/imunologia , Indóis/farmacocinética , Indóis/uso terapêutico , Interleucina-2/sangue , Interleucina-2/metabolismo , Células Jurkat , Microssomos/metabolismo , Modelos Biológicos , Ovalbumina/imunologia , Ligação Proteica , Piridinas/farmacocinética , Piridinas/uso terapêutico , Pirróis/farmacocinética , Pirróis/uso terapêutico , Ratos , Relação Estrutura-AtividadeRESUMO
The guardian of the genome, p53, is the most mutated protein found in all cancer cells. Restoration of wild-type activity to mutant p53 offers promise to eradicate cancer cells using novel pharmacological agents. Several molecules have already been found to activate mutant p53. While the exact mechanism of action of these compounds has not been fully understood, a transiently open pocket has been identified in some mutants. In our study, we docked twelve known activators to p53 into the open pocket to further understand their mechanism of action and rank the best binders. In addition, we predicted the absorption, distribution, metabolism, excretion and toxicity properties of these compounds to assess their pharmaceutical usefulness. Our studies showed that alkylating ligands do not all bind at the same position, probably due to their varying sizes. In addition, we found that non-alkylating ligands are capable of binding at the same pocket and directly interacting with Cys124. The comparison of the different ligands demonstrates that stictic acid has a great potential as a p53 activator in terms of less adverse effects although it has poorer pharmacokinetic properties.
Assuntos
Proteína Supressora de Tumor p53/química , Proteína Supressora de Tumor p53/metabolismo , Alquilação , Amifostina/química , Amifostina/farmacocinética , Amifostina/toxicidade , Compostos Aza/química , Compostos Aza/farmacocinética , Compostos Aza/toxicidade , Compostos Bicíclicos Heterocíclicos com Pontes/química , Compostos Bicíclicos Heterocíclicos com Pontes/farmacocinética , Compostos Bicíclicos Heterocíclicos com Pontes/toxicidade , Avaliação Pré-Clínica de Medicamentos , Elipticinas/química , Elipticinas/farmacocinética , Elipticinas/farmacologia , Elipticinas/toxicidade , Compostos Heterocíclicos de 4 ou mais Anéis/química , Compostos Heterocíclicos de 4 ou mais Anéis/farmacocinética , Compostos Heterocíclicos de 4 ou mais Anéis/toxicidade , Humanos , Cinética , Ligantes , Mercaptoetilaminas/química , Mercaptoetilaminas/farmacocinética , Mercaptoetilaminas/toxicidade , Simulação de Dinâmica Molecular , Mutagênese Sítio-Dirigida , Mutação , Oxepinas/química , Oxepinas/farmacocinética , Oxepinas/toxicidade , Ligação Proteica , Pirimidinas/química , Pirimidinas/farmacologia , Pirimidinas/toxicidade , Quinuclidinas/química , Quinuclidinas/farmacocinética , Quinuclidinas/toxicidade , Proteína Supressora de Tumor p53/genéticaRESUMO
Bond activation by gold is of imminent interest with respect to catalytic activity. By coordination of an AuCl fragment onto the P-P σ-bond of an azadiphosphiridine, the P-P bond is cleaved to give a PNP type of ligand in the gold(I) complex. Another equivalent of the gold precursor selectively binds on a P lone pair. The bonding situation was further studied by means of computation, indicating the existence of a 3-center-2-electron bond.