Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 1.198
Filtrar
1.
Nat Commun ; 12(1): 5491, 2021 10 07.
Artigo em Inglês | MEDLINE | ID: mdl-34620856

RESUMO

Many neuron types consist of populations with continuously varying molecular properties. Here, we show a continuum of postsynaptic molecular properties in three types of neurons and assess the functional correlates in cerebellar unipolar brush cells (UBCs). While UBCs are generally thought to form discrete functional subtypes, with mossy fiber (MF) activation increasing firing in ON-UBCs and suppressing firing in OFF-UBCs, recent work also points to a heterogeneity of response profiles. Indeed, we find a continuum of response profiles that reflect the graded and inversely correlated expression of excitatory mGluR1 and inhibitory mGluR2/3 pathways. MFs coactivate mGluR2/3 and mGluR1 in many UBCs, leading to sequential inhibition-excitation because mGluR2/3-currents are faster. Additionally, we show that DAG-kinase controls mGluR1 response duration, and that graded DAG kinase levels correlate with systematic variation of response duration over two orders of magnitude. These results demonstrate that continuous variations in metabotropic signaling can generate a stable cell-autonomous basis for temporal integration and learning over multiple time scales.


Assuntos
Córtex Cerebelar/metabolismo , Fibras Nervosas/fisiologia , Neurônios/fisiologia , Receptores de Glutamato Metabotrópico/metabolismo , Potenciais de Ação/efeitos dos fármacos , Aminoácidos/farmacologia , Animais , Córtex Cerebelar/citologia , Estimulação Elétrica , Antagonistas de Aminoácidos Excitatórios , Feminino , Masculino , Camundongos Endogâmicos C57BL , Técnicas de Patch-Clamp/métodos , Receptores de Glutamato Metabotrópico/antagonistas & inibidores , Transmissão Sináptica/efeitos dos fármacos , Transmissão Sináptica/fisiologia , Fatores de Tempo , Xantenos/farmacologia
2.
Nat Commun ; 12(1): 5426, 2021 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-34521824

RESUMO

Much hope in drug development comes from the discovery of positive allosteric modulators (PAM) that display target subtype selectivity and act by increasing agonist potency and efficacy. How such compounds can allosterically influence agonist action remains unclear. Metabotropic glutamate receptors (mGlu) are G protein-coupled receptors that represent promising targets for brain diseases, and for which PAMs acting in the transmembrane domain have been developed. Here, we explore the effect of a PAM on the structural dynamics of mGlu2 in optimized detergent micelles using single molecule FRET at submillisecond timescales. We show that glutamate only partially stabilizes the extracellular domains in the active state. Full activation is only observed in the presence of a PAM or the Gi protein. Our results provide important insights on the role of allosteric modulators in mGlu activation, by stabilizing the active state of a receptor that is otherwise rapidly oscillating between active and inactive states.


Assuntos
Ácido Glutâmico/farmacologia , Receptores de Glutamato Metabotrópico/agonistas , Receptores de Glutamato Metabotrópico/química , Regulação Alostérica/efeitos dos fármacos , Sítio Alostérico , Aminoácidos/química , Aminoácidos/farmacologia , Compostos de Bifenilo/química , Compostos de Bifenilo/farmacologia , Compostos Bicíclicos com Pontes/química , Compostos Bicíclicos com Pontes/farmacologia , Compostos Bicíclicos Heterocíclicos com Pontes/química , Compostos Bicíclicos Heterocíclicos com Pontes/farmacologia , Domínio Catalítico , Membrana Celular/efeitos dos fármacos , Membrana Celular/metabolismo , Ésteres do Colesterol/química , Ésteres do Colesterol/farmacologia , Diosgenina/análogos & derivados , Diosgenina/química , Diosgenina/farmacologia , Dissacarídeos/química , Dissacarídeos/farmacologia , Transferência Ressonante de Energia de Fluorescência , Expressão Gênica , Glucosídeos/química , Glucosídeos/farmacologia , Glicolipídeos/química , Glicolipídeos/farmacologia , Células HEK293 , Humanos , Indanos/química , Indanos/farmacologia , Micelas , Octoxinol/química , Octoxinol/farmacologia , Ligação Proteica , Conformação Proteica , Multimerização Proteica , Receptores de Glutamato Metabotrópico/genética , Receptores de Glutamato Metabotrópico/metabolismo , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Imagem Individual de Molécula , Xantenos/química , Xantenos/farmacologia
3.
Am J Physiol Renal Physiol ; 321(4): F424-F430, 2021 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-34396788

RESUMO

Chronic metabolic acidosis stimulates cell-mediated net Ca2+ efflux from bone mediated by increased osteoblastic cyclooxygenase 2, leading to prostaglandin E2-induced stimulation of receptor activator of NF-κB ligand-induced osteoclastic bone resorption. Ovarian cancer G protein-coupled receptor-1 (OGR1), an osteoblastic H+-sensing G protein-coupled receptor, is activated by acidosis and leads to increased bone resorption. As regulator of G protein signaling (RGS) proteins limit GPCR signaling, we tested whether RGS proteins themselves are regulated by metabolic acidosis. Primary osteoblasts were isolated from neonatal mouse calvariae and incubated in physiological neutral or acidic (MET) medium. Cells were collected, and RNA was extracted for real-time PCR analysis with mRNA levels normalized to ribosomal protein L13a. RGS1, RGS2, RGS3, RGS4, RGS10, RGS11, and RGS18 mRNA did not differ between MET and neutral medium; however, by 30 min, MET decreased RGS16, which persisted for 60 min and 3 h. Incubation of osteoblasts with the OGR1 inhibitor CuCl2 inhibited the MET-induced increase in RGS16 mRNA. Gallein, a specific inhibitor of Gßγ signaling, was used to determine if downstream signaling by the ßγ-subunit was critical for the response to acidosis. Gallein decreased net Ca2+ efflux from calvariae and cyclooxygenase 2 and receptor activator of NF-κB ligand gene expression from isolated osteoblasts. These results indicate that regulation of RGS16 plays an important role in modulating the response of the osteoblastic GPCR OGR1 to metabolic acidosis and subsequent stimulation of osteoclastic bone resorption.NEW & NOTEWORTHY The results presented in this study indicate that regulation of regulator of G protein signaling 16 and G protein signaling in the osteoblast plays an important role in modulating the response of osteoblastic ovarian cancer G protein-coupled receptor 1 (OGR1) to metabolic acidosis and the subsequent stimulation of osteoclastic bone resorption. Further characterization of the regulation of OGR1 in metabolic acidosis-induced bone resorption will help in understanding bone loss in acidotic patients with chronic kidney disease.


Assuntos
Acidose/metabolismo , Proteínas de Ligação ao GTP/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Osteoblastos/metabolismo , Proteínas RGS/metabolismo , Animais , Bicarbonatos/administração & dosagem , Bicarbonatos/farmacologia , Dióxido de Carbono , Células Cultivadas , Proteínas de Ligação ao GTP/genética , Concentração de Íons de Hidrogênio , Camundongos , Proteínas RGS/genética , RNA/genética , RNA/metabolismo , Xantenos/farmacologia
4.
Molecules ; 26(14)2021 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-34299503

RESUMO

Naturally occurring flavonoids are found as secondary metabolites in a wide number of plants exploited for both medicine and food and have long been known to be endowed with multiple biological activities, making them useful tools for the treatment of different pathologies. Due to the versatility of the scaffolds and the vast possibilities of appropriate decoration, they have also been regarded as fruitful sources of lead compounds and excellent chemical platforms for the development of bioactive synthetic compounds. Flavone-8-acetic acid (FAA) and 5,6-dimethylxanthone acetic acid (DMXAA) emerged for their antitumour potential due to the induction of cytokines and consequent rapid haemorrhagic necrosis of murine tumour vasculature, and different series of derivatives have been designed thereafter. Although the promising DMXAA failed in phase III clinical trials because of strict species-specificity, a boost in research came from the recent identification of the stimulator of interferon genes (STING), responsible for supporting tumoural innate immune responses, as a possible biological target. Consequently, in the last decade a renewal of interest for these flavonoid-based structures was noticed, and novel derivatives have been synthesised and evaluated for a deeper understanding of the molecular features needed for affecting human cells. Undoubtedly, these natural-derived molecules deserve further investigation and still appear attractive in an anticancer perspective.


Assuntos
Flavonoides/farmacologia , Neoplasias/tratamento farmacológico , Animais , Antineoplásicos/farmacologia , Ensaios Clínicos Fase III como Assunto , Humanos , Xantenos/farmacologia , Xantonas/farmacologia
6.
Sci Rep ; 11(1): 13779, 2021 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-34215805

RESUMO

Microtiter plate methods are commonly used for biofilm assessment. However, results obtained with these methods have often been difficult to reproduce. Hence, it is important to obtain a better understanding of the repeatability and reproducibility of these methods. An interlaboratory study was performed in five different laboratories to evaluate the reproducibility and responsiveness of three methods to quantify Staphylococcus aureus biofilm formation in 96-well microtiter plates: crystal violet, resazurin, and plate counts. An inter-lab protocol was developed for the study. The protocol was separated into three steps: biofilm growth, biofilm challenge, biofilm assessment. For control experiments participants performed the growth and assessment steps only. For treatment experiments, all three steps were performed and the efficacy of sodium hypochlorite (NaOCl) in killing S. aureus biofilms was evaluated. In control experiments, on the log10-scale, the reproducibility SD (SR) was 0.44 for crystal violet, 0.53 for resazurin, and 0.92 for the plate counts. In the treatment experiments, plate counts had the best responsiveness to different levels of efficacy and also the best reproducibility with respect to responsiveness (Slope/SR = 1.02), making it the more reliable method to use in an antimicrobial efficacy test. This study showed that the microtiter plate is a versatile and easy-to-use biofilm reactor, which exhibits good repeatability and reproducibility for different types of assessment methods, as long as a suitable experimental design and statistical analysis is applied.


Assuntos
Técnicas Bacteriológicas , Biofilmes/crescimento & desenvolvimento , Hipoclorito de Sódio/farmacologia , Staphylococcus aureus/efeitos dos fármacos , Antibacterianos/farmacologia , Biofilmes/efeitos dos fármacos , Violeta Genciana/farmacologia , Humanos , Oxazinas/farmacologia , Infecções Estafilocócicas/diagnóstico , Infecções Estafilocócicas/microbiologia , Staphylococcus aureus/crescimento & desenvolvimento , Staphylococcus aureus/patogenicidade , Xantenos/farmacologia
7.
mBio ; 12(3): e0059221, 2021 06 29.
Artigo em Inglês | MEDLINE | ID: mdl-34126765

RESUMO

The opportunistic pathogen Pseudomonas aeruginosa is a leading cause of nosocomial infections, which are becoming increasingly difficult to treat due to antibiotic resistance. Polyphosphate (polyP) plays a key role in P. aeruginosa virulence, stress response, and antibiotic tolerance, suggesting an attractive drug target. Here, we show that the small molecule gallein disrupts polyphosphate homeostasis by inhibiting all members of both polyphosphate kinase (PPK) families (PPK1 and PPK2) encoded by P. aeruginosa, demonstrating dual-specificity PPK inhibition for the first time. Inhibitor treatment phenocopied ppk deletion to reduce cellular polyP accumulation and attenuate biofilm formation, motility, and pyoverdine and pyocyanin production. Most importantly, gallein attenuated P. aeruginosa virulence in a Caenorhabditis elegans infection model and synergized with antibiotics while exhibiting negligible toxicity toward the nematodes or HEK293T cells, suggesting our discovery of dual-specificity PPK inhibitors as a promising starting point for the development of new antivirulence therapeutics. IMPORTANCE Many priority bacterial pathogens such as P. aeruginosa encode both PPK1 and PPK2 enzymes to maintain polyphosphate homeostasis. While PPK1 and PPK2 have distinct structures and catalytic mechanisms, they are both capable of synthesizing and consuming polyphosphate; thus, PPK2 enzymes can compensate for the loss of PPK1 and vice versa. In this study, we identified the small molecule gallein as a dual-specificity inhibitor of both PPK1 and PPK2 enzyme families in P. aeruginosa. Inhibitor treatment reduced cellular polyP in wild-type (WT), Δppk1, and Δppk2 strains to levels that were on par with the Δppk1 Δppk2A Δppk2B Δppk2C knockout control. Treatment also attenuated biofilm formation, motility, toxin production, and virulence to a similar extent, thereby elucidating a hitherto-undocumented role of PPK2 enzymes in P. aeruginosa virulence phenotypes. This work therefore establishes PPK2s, in addition to PPK1, as valuable drug targets in P. aeruginosa and provides a favorable starting molecule for future inhibitor design efforts.


Assuntos
Antibacterianos/farmacologia , Inibidores Enzimáticos/farmacologia , Fosfotransferases (Aceptor do Grupo Fosfato)/antagonistas & inibidores , Pseudomonas aeruginosa/efeitos dos fármacos , Pseudomonas aeruginosa/patogenicidade , Xantenos/farmacologia , Animais , Antibacterianos/uso terapêutico , Caenorhabditis elegans/efeitos dos fármacos , Caenorhabditis elegans/microbiologia , Inibidores Enzimáticos/uso terapêutico , Células HEK293 , Humanos , Fenótipo , Fosfotransferases (Aceptor do Grupo Fosfato)/classificação , Infecções por Pseudomonas/tratamento farmacológico , Infecções por Pseudomonas/microbiologia , Pseudomonas aeruginosa/enzimologia , Virulência/efeitos dos fármacos , Xantenos/uso terapêutico
8.
Int J Mol Sci ; 22(11)2021 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-34071042

RESUMO

Osteoporosis is a chronic disease that has become a serious public health problem due to the associated reduction in quality of life and its increasing financial burden. It is known that inhibiting osteoclast differentiation and promoting osteoblast formation prevents osteoporosis. As there is no drug with this dual activity without clinical side effects, new alternatives are needed. Here, we demonstrate that austalide K, isolated from the marine fungus Penicillium rudallenes, has dual activities in bone remodeling. Austalide K inhibits the receptor activator of nuclear factor-κB ligand (RANKL)-induced osteoclast differentiation and improves bone morphogenetic protein (BMP)-2-mediated osteoblast differentiation in vitro without cytotoxicity. The nuclear factor of activated T cells c1 (NFATc1), tartrate-resistant acid phosphatase (TRAP), dendritic cell-specific transmembrane protein (DC-STAMP), and cathepsin K (CTSK) osteoclast-formation-related genes were reduced and alkaline phosphatase (ALP), runt-related transcription factor 2 (Runx2), osteocalcin (OCN), and osteopontin (OPN) (osteoblast activation-related genes) were simultaneously upregulated by treatment with austalide K. Furthermore, austalide K showed good efficacy in an LPS-induced bone loss in vivo model. Bone volume, trabecular separation, trabecular thickness, and bone mineral density were recovered by austalide K. On the basis of these results, austalide K may lead to new drug treatments for bone diseases such as osteoporosis.


Assuntos
Conservadores da Densidade Óssea/uso terapêutico , Reabsorção Óssea/prevenção & controle , Osteoblastos/efeitos dos fármacos , Osteoclastos/efeitos dos fármacos , Penicillium/química , Xantenos/uso terapêutico , Animais , Conservadores da Densidade Óssea/isolamento & purificação , Conservadores da Densidade Óssea/farmacologia , Reabsorção Óssea/induzido quimicamente , Diferenciação Celular/efeitos dos fármacos , Modelos Animais de Doenças , Avaliação Pré-Clínica de Medicamentos , Regulação da Expressão Gênica/efeitos dos fármacos , Sedimentos Geológicos/microbiologia , Lipopolissacarídeos/toxicidade , Masculino , Camundongos , Camundongos Endogâmicos ICR , Estrutura Molecular , Fatores de Transcrição NFATC/biossíntese , Fatores de Transcrição NFATC/genética , Osteoporose , Penicillium/isolamento & purificação , Ligante RANK/farmacologia , Fosfatase Ácida Resistente a Tartarato/antagonistas & inibidores , Xantenos/isolamento & purificação , Xantenos/farmacologia
9.
Acta Chim Slov ; 68(1): 51-64, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34057520

RESUMO

In this work the multi-component reactions of either of the arylhydrazocyclohexan-1,3-dione derivatives 3a-c with either of benzaldehyde (4a), 4-chlorobenzaldehyde (4b) or 4-methoxybenzaldehyde (4c) and either malononitrile (5a) or ethyl cyanoacetate (5b) giving the 5,6,7,8-tetrahydro-4H-chromene derivatives 6a-r, respectively, are presented. The reaction of two equivalents of cyclohexan-1,3-dione with benzaldehyde gave the hexahydro-1H-xanthene-1,8(2H)-dione derivative 7. On the other hand, the multi-component reactions of compound 1 with dimedone and benzaldehyde gave 13. Both of 7 and 13 underwent heterocyclization reactions to produce fused thiophene, pyran and thiazole derivatives. Selected compounds among the synthesized compounds were tested against six cancer cell lines where most of them gave high inhibitions; especially compounds 3b, 3c, 6b, 6c, 6d, 6f, 6i, 6m, 6n, 8b, 14a, 15 and 16 being the most cytotoxic compounds. Further tests against the five tyrosine kinases c-Kit, Flt-3, VEGFR-2, EGFR, and PDGFR and Pim-1 kinase showed that compounds 3c, 6c, 6d, 6f, 6n, 14a and 15 were the most potent of the tested compounds toward the five tyrosine kinases and compounds 3c, 6c, 6d, 6n and 15 displayed the highest inhibitions toward Pim-1 kinase.


Assuntos
Antineoplásicos/farmacologia , Cicloexanonas/química , Inibidores de Proteínas Quinases/farmacologia , Xantenos/farmacologia , Antineoplásicos/síntese química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Hidrazonas/química , Estrutura Molecular , Inibidores de Proteínas Quinases/síntese química , Relação Estrutura-Atividade , Tiazóis/síntese química , Tiazóis/farmacologia , Tiofenos/síntese química , Tiofenos/farmacologia , Xantenos/síntese química
10.
Biosci Biotechnol Biochem ; 85(3): 520-527, 2021 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-33624779

RESUMO

The purpose of this study is to investigate the protective effect of gambogenic acid (GA) in acetaminophen (APAP)-induced hepatotoxicity in rat models. GA (10 mg/kg) was administered intraperitoneal (i.p.) to rats for 7 consecutive days followed by APAP (500 mg/kg) single dose (i.p.) on the final day after GA administration. The levels of MDA, GSH, SOD, CAT, GPx, GST, ALP, AST, ALT, proinflammatory cytokines (TNF-α, IL-1ß, IL-6), apoptosis markers (caspase-3 and -9, Bax, Bcl-2), 4-hydroxynonenal (4-HNE), and prostaglandin E2 (PGE2) were evaluated. Results exhibited protective effects of GA by inhibiting inflammation, preventing oxidative stress and apoptosis in APAP-induced liver. Histopathological changes caused by APAP were attenuated, protein expressions of phosphatidylinositol 3-kinase/protein kinase B (PI3K/Akt) were upregulated, and nuclear factor-kappa ß (NF-kß) was downregulated by GA. In summary, GA significantly exerted anti-inflammatory and antiapoptotic effects against APAP-induced hepatotoxicity potentially through regulation of PI3K/Akt and NF-kß signaling pathways.


Assuntos
Acetaminofen/toxicidade , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Fígado/efeitos dos fármacos , NF-kappa B/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais/efeitos dos fármacos , Xantenos/farmacologia , Animais , Modelos Animais de Doenças , Fígado/enzimologia , Fígado/metabolismo , Masculino , Ratos , Ratos Sprague-Dawley
11.
Int Immunopharmacol ; 90: 107200, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33246825

RESUMO

Hypertrophic scar (HS) is a dermal fibroproliferative disease that often occurs following abnormal wound healing. To date, there is no satisfied treatment strategies for improvement of scar formation with few side effects. The effects of gambogenic acid (GNA) on scar hypertrophy has not been studied previously. The present study was undertaken to find out the scar-reducing effects of GNA (0.48, 0.96 or 1.92 mg/ml) on skin wounds in rabbit ears. Scar evaluation index (SEI), collagen I (Col1) and collagen III (Col3), microvascular density (MVD), CD4+T cells and macrophages, vascular endothelial growth factor receptor 2 (VEGFR2), fibroblast growth factor receptor 1 (FGFR1), phospho-VEGFR 2 (p-VEGFR2) and p-FGFR1, interleukin (IL)-1ß, IL-6, IL-10 and tumor necrosis factor (TNF)-α, transforming growth factor (TGF)-ß1 and connective tissue growth factor (CTGF) in scar tissue were detected using various methods, respectively. Our data showed that GNA significantly reduced SEI, and the expression of Col1 and Col3 in scar tissue in a concentration-dependent manner. Also, it decreased MVD, the infiltration of CD4+T cells and macrophages, and the levels of VEGFR2, p-VEGFR2, FGFR1, p-FGFR1, TGF-ß1, CTGF, IL-1ß, IL-6, TNF-α, in addition to upregulated IL-10 in scar tissue. As a result, this study revealed that GNA reduced HS formation, which was associated with the inhibition of neoangiogenesis, local inflammatory response and growth factor expression in scar tissue during wound healing. These findings suggested that GNA may be considered as a preventive and therapeutic candidate for HS.


Assuntos
Inibidores da Angiogênese/farmacologia , Anti-Inflamatórios/farmacologia , Cicatriz Hipertrófica/prevenção & controle , Neovascularização Fisiológica/efeitos dos fármacos , Pele/efeitos dos fármacos , Cicatrização/efeitos dos fármacos , Ferimentos e Lesões/tratamento farmacológico , Xantenos/farmacologia , Proteínas Angiogênicas/metabolismo , Animais , Cicatriz Hipertrófica/imunologia , Cicatriz Hipertrófica/metabolismo , Cicatriz Hipertrófica/patologia , Colágeno/metabolismo , Citocinas/metabolismo , Modelos Animais de Doenças , Orelha , Feminino , Mediadores da Inflamação/metabolismo , Masculino , Coelhos , Transdução de Sinais , Pele/imunologia , Pele/metabolismo , Pele/patologia , Ferimentos e Lesões/imunologia , Ferimentos e Lesões/metabolismo , Ferimentos e Lesões/patologia
12.
Eur J Med Chem ; 210: 113085, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33310284

RESUMO

BACKGROUND: Xanthenes are a special class of oxygen-incorporating tricyclic compounds. Structurally related to xanthones, the presence of different substituents in position 9 strongly influences their physical and chemical properties, as well as their biological applications. This review explores the synthetic methodologies developed to obtain 9H-xanthene, 9-hydroxyxanthene and xanthene-9-carboxylic acid, as well as respective derivatives, from simple starting materials or through modification of related structures. Azaxanthenes, bioisosteres of xanthenes, are also explored. Efficiency, safety, ecological impact and applicability of the described synthetic methodologies are discussed. Synthesis of multi-functionalized derivatives with drug-likeness properties are also reported and their activities explored. Synthetic methodologies for obtaining (aza)xanthenes from simple building blocks are available, and electrochemical and/or metal free procedures recently developed arise as greener and efficient methodologies. Nonetheless, the synthesis of xanthenes through the modification of the carbonyl in position 9 of xanthones represents the most straightforward procedure to easily obtain a variety of (aza)xanthenes. (Aza)xanthene derivatives displayed biological activity as neuroprotector, antitumor, antimicrobial, among others, proving the versatility of this nucleus for different biological applications. However, in some cases their chemical structures suggest a lack of pharmacokinetic properties being associated with safety concerns, which should be overcome if intended for clinical evaluation.


Assuntos
Anti-Infecciosos/farmacologia , Antineoplásicos/farmacologia , Neoplasias/tratamento farmacológico , Fármacos Neuroprotetores/farmacologia , Xantenos/farmacologia , Anti-Infecciosos/síntese química , Anti-Infecciosos/química , Antineoplásicos/síntese química , Antineoplásicos/química , Bactérias/efeitos dos fármacos , Química Farmacêutica , Fungos/efeitos dos fármacos , Humanos , Fármacos Neuroprotetores/síntese química , Fármacos Neuroprotetores/química , Xantenos/síntese química , Xantenos/química
13.
SAR QSAR Environ Res ; 31(12): 905-921, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33236957

RESUMO

Cancer remains one of the leading causes of death in humans, and new drug substances are therefore being developed. Thus, the anti-cancer activity of xanthene derivatives has become an important topic in the development of new and potent anti-cancer drug substances. Previously published novel series of xanthen-3-one and xanthen-1,8-dione derivatives have been synthesized in one of our laboratories and showed anti-proliferative activity in HeLa cancer cell lines. This series serves as a good basis to develop quantitative structure-activity relationship (QSAR), to study the relations between anti-proliferative activity and chemical structures. A QSAR model has been derived that relies only on two-dimensional molecular descriptors, providing mechanistic insight into the anti-proliferative activity of xanthene derivatives. The model is validated internally and externally and additionally with the set of inactive compounds of the original data, confirming model applicability for the design and discovery of novel xanthene derivatives. The QSAR model is available at the QsarDB repository (http://dx.doi.10.15152/QDB.237).


Assuntos
Antineoplásicos/farmacologia , Relação Quantitativa Estrutura-Atividade , Xantenos/farmacologia , Feminino , Células HeLa , Humanos , Modelos Moleculares
14.
Mol Cell Neurosci ; 109: 103566, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33049367

RESUMO

Human SH-SY5Y neuroblastoma cells stably expressing exogenous CB1 (CB1XS) or CB2 (CB2XS) receptors were developed to investigate endocannabinoid signaling in the extension of neuronal projections. Expression of cannabinoid receptors did not alter proliferation rate, viability, or apoptosis relative to parental SH-SY5Y. Transcripts for endogenous cannabinoid system enzymes (diacylglycerol lipase, monoacylglycerol lipase, α/ß-hydrolase domain containing proteins 6 and 12, N-acyl phosphatidylethanolamine-phospholipase D, and fatty acid amide hydrolase) were not altered by CB1 or CB2 expression. Endocannabinoid ligands 2-arachidonoylglycerol (2-AG) and anandamide were quantitated in SH-SY5Y cells, and diacylglycerol lipase inhibitor tetrahydrolipstatin decreased 2-AG abundance by 90% but did not alter anandamide abundance. M3 muscarinic agonist oxotremorine M, and inhibitors of monoacylglycerol lipase and α/ß hydrolase domain containing proteins 6 &12 increased 2-AG abundance. CB1 receptor expression increased lengths of short (<30 µm) and long (>30 µm) projections, and this effect was significantly reduced by tetrahydrolipstatin, indicative of stimulation by endogenously produced 2-AG. Pertussis toxin, Gßγ inhibitor gallein, and ß-arrestin inhibitor barbadin did not significantly alter long projection length in CB1XS, but significantly reduced short projections, with gallein having the greatest inhibition. The rho kinase inhibitor Y27632 increased CB1 receptor-mediated long projection extension, indicative of actin cytoskeleton involvement. CB1 receptor expression increased GAP43 and ST8SIA2 mRNA and decreased ITGA1 mRNA, whereas CB2 receptor expression increased NCAM and SYT mRNA. We propose that basal endogenous production of 2-AG provides autocrine stimulation of CB1 receptor signaling through Gi/o, Gßγ, and ß-arrestin mechanisms to promote neuritogenesis, and rho kinase influences process extension.


Assuntos
Endocanabinoides/fisiologia , Neuritos/ultraestrutura , Receptor CB1 de Canabinoide/fisiologia , Receptor CB2 de Canabinoide/fisiologia , Citoesqueleto de Actina/ultraestrutura , Amidas/farmacologia , Apoptose/efeitos dos fármacos , Ácidos Araquidônicos/biossíntese , Linhagem Celular Tumoral , Endocanabinoides/biossíntese , Regulação da Expressão Gênica/efeitos dos fármacos , Glicerídeos/biossíntese , Humanos , Lipase Lipoproteica/antagonistas & inibidores , Lipase Lipoproteica/metabolismo , Proteínas de Neoplasias/efeitos dos fármacos , Proteínas de Neoplasias/fisiologia , Proteínas do Tecido Nervoso/biossíntese , Proteínas do Tecido Nervoso/genética , Neuroblastoma , Orlistate/farmacologia , Oxotremorina/farmacologia , Toxina Pertussis/farmacologia , Alcamidas Poli-Insaturadas , Piridinas/farmacologia , Pirimidinas/farmacologia , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , Receptor CB1 de Canabinoide/efeitos dos fármacos , Receptor CB2 de Canabinoide/efeitos dos fármacos , Proteínas Recombinantes/biossíntese , Transdução de Sinais , Xantenos/farmacologia
15.
Bioorg Chem ; 104: 104190, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32919130

RESUMO

Interactions of two newly synthesized and six previously reported benzoxanthene lignans (BXLs), analogues of rare natural products, with DNA/RNA, G-quadruplex and HSA were evaluated by a set of spectrophotometric methods. Presence/absence of methoxy and hydroxy groups on the benzoxanthene core and minor modifications at C-1/C-2 side pendants - presence/absence of phenyl ring and presence/absence of methoxy and hydroxy groups on phenyl ring - influenced the fluorescence changes and the binding strength to double-stranded (ds-) and G-quadruplex structures. In general, compounds without phenyl ring showed stronger fluorescence changes upon binding than phenyl-substituted BXLs. On the other hand, BXLs with an unsubstituted phenyl ring showed the best stabilization effects of G-quadruplex. Circular dichroism spectroscopy results suggest mixed binding mode, groove binding and partial intercalation, to ds-DNA/RNA and end-stacking to top or bottom G-tetrads as the main binding modes of BXLs to those targets. All compounds exhibited micromolar binding affinities toward HSA and an increased protein thermal stability. Moderate to strong antiradical scavenging activity was observed for all BXLs with hydroxy groups at C-6, C-9 and C-10 positions of the benzoxanthene core, except for derivative bearing methoxy groups at these positions. BXLs with unsubstituted or low-substituted phenyl ring and one derivative without phenyl ring showed strong growth inhibition of Gram-positive Staphylococcus aureus. All compounds showed moderate to strong tumor cell growth-inhibitory activity and cytotoxicity.


Assuntos
Antineoplásicos/farmacologia , DNA Tumoral Circulante/química , Lignanas/farmacologia , RNA Neoplásico/química , Albumina Sérica Humana/química , Xantenos/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Escherichia coli K12/citologia , Escherichia coli K12/efeitos dos fármacos , Humanos , Lignanas/síntese química , Lignanas/química , Estrutura Molecular , Salmonella enterica/citologia , Salmonella enterica/efeitos dos fármacos , Staphylococcus aureus/citologia , Staphylococcus aureus/efeitos dos fármacos , Relação Estrutura-Atividade , Células Tumorais Cultivadas , Xantenos/síntese química , Xantenos/química
16.
Life Sci ; 262: 118481, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-32971104

RESUMO

AIMS: G-protein coupled receptors (GPCRs) tightly regulate platelet function by interacting with various physiological agonists. An essential mediator of GPCR signaling is the G protein αßγ heterotrimers, in which the ßγ subunits are central players in downstream signaling. Herein, we investigated the role of Gßγ subunits in platelet function, hemostasis and thrombogenesis. METHODS: To achieve this goal, platelets from both mice and humans were employed in the context of a small molecule inhibitor of Gßγ, namely gallein. We used an aggregometer to examine aggregation and dense granules secretion. We also used flow cytometry for P-selectin and PAC1 to determine the impact of inhibiting Gßγ on α -granule secretion and αIIbß3 activation. Clot retraction and the platelet spreading assay were used to examine Gßγ role in outside-in platelet signaling, whereas Western blot was employed to examine its role in Akt activation. Finally, we used the bleeding time assay and the FeCl3-induced carotid-artery injury thrombosis model to determine Gßγ contribution to in vivo platelet function. RESULTS: We observed that gallein inhibits platelet aggregation and secretion in response to agonist stimulation, in both mouse and human platelets. Furthermore, gallein also exerted inhibitory effects on integrin αIIbß3 activation, clot retraction, platelet spreading and Akt activation/phosphorylation. Finally, gallein's inhibitory effects manifested in vivo, as documented by its ability to modulate physiological hemostasis and delay thrombus formation. CONCLUSION: Our findings demonstrate, for the first time, that Gßγ subunits directly regulate GPCR-dependent platelet function, in vitro and in vivo. Moreover, these data highlight Gßγ as a novel therapeutic target for managing thrombotic disorders.


Assuntos
Plaquetas/fisiologia , Subunidades beta da Proteína de Ligação ao GTP/metabolismo , Subunidades gama da Proteína de Ligação ao GTP/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Trombose/patologia , Animais , Retração do Coágulo/fisiologia , Modelos Animais de Doenças , Hemostasia/fisiologia , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Agregação Plaquetária/fisiologia , Complexo Glicoproteico GPIIb-IIIa de Plaquetas/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais/fisiologia , Xantenos/farmacologia
17.
Am J Physiol Endocrinol Metab ; 319(5): E877-E892, 2020 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-32893672

RESUMO

Free fatty acid (FFA) receptors FFA1 and FFA4 are omega-3 molecular targets in metabolic diseases; however, their function in cancer cachexia remains unraveled. We assessed the role of FFA1 and FFA4 receptors in the mouse model of cachexia induced by Lewis lung carcinoma (LLC) cell implantation. Naturally occurring ligands such as α-linolenic acid (ALA) and docosahexaenoic acid (DHA), the synthetic FFA1/FFA4 agonists GW9508 and TUG891, or the selective FFA1 GW1100 or FFA4 AH7614 antagonists were tested. FFA1 and FFA4 expression and other cachexia-related parameters were evaluated. GW9508 and TUG891 decreased tumor weight in LLC-bearing mice. Regarding cachexia-related end points, ALA, DHA, and the preferential FFA1 agonist GW9508 rescued body weight loss. Skeletal muscle mass was reestablished by ALA treatment, but this was not reflected in the fiber cross-sectional areas (CSA) measurement. Otherwise, TUG891, GW1100, or AH7614 reduced the muscle fiber CSA. Treatments with ALA, GW9508, GW1100, or AH7614 restored white adipose tissue (WAT) depletion. As for inflammatory outcomes, ALA improved anemia, whereas GW9508 reduced splenomegaly. Concerning behavioral impairments, ALA and GW9508 rescued locomotor activity, whereas ALA improved motor coordination. Additionally, DHA improved grip strength. Notably, GW9508 restored abnormal brain glucose metabolism in different brain regions. The GW9508 treatment increased leptin levels, without altering uncoupling protein-1 downregulation in visceral fat. LLC-cachectic mice displayed FFA1 upregulation in subcutaneous fat, but not in visceral fat or gastrocnemius muscle, whereas FFA4 was unaltered. Overall, the present study shed new light on FFA1 and FFA4 receptors' role in metabolic disorders, indicating FFA1 receptor agonism as a promising strategy in mitigating cancer cachexia.


Assuntos
Peso Corporal/efeitos dos fármacos , Caquexia/tratamento farmacológico , Carcinoma Pulmonar de Lewis/metabolismo , Ácidos Docosa-Hexaenoicos/uso terapêutico , Receptores Acoplados a Proteínas G/metabolismo , Ácido alfa-Linoleico/uso terapêutico , Animais , Benzoatos/farmacologia , Compostos de Bifenilo/farmacologia , Caquexia/etiologia , Caquexia/metabolismo , Carcinoma Pulmonar de Lewis/complicações , Modelos Animais de Doenças , Ácidos Docosa-Hexaenoicos/farmacologia , Metilaminas/farmacologia , Camundongos , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/metabolismo , Transplante de Neoplasias , Fenilpropionatos/farmacologia , Propionatos/farmacologia , Pirimidinas/farmacologia , Receptores Acoplados a Proteínas G/agonistas , Sulfonamidas/farmacologia , Xantenos/farmacologia , Ácido alfa-Linoleico/farmacologia
18.
Int J Mycobacteriol ; 9(3): 274-280, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32862160

RESUMO

Background: Because pyrazinamide (PZA) is only effective for Mycobacterium tuberculosis at an acidic pH, susceptibility tests are more difficult to perform than those for other anti-tuberculosis (TB) drugs. The purpose of our work was to investigate the effectiveness of colorimetric methods to detect PZA susceptibility and to detect pncA gene mutations in resistant isolates by sequence analysis. Methods: In this study, 30 clinical isolates and 2 reference isolates were used, 15 of which were resistant to PZA. The PZA susceptibility of all the isolates was determined by the BACTEC MGIT 960 reference method. As colorimetric methods, Resazurin Microtiter Assay (REMA), Nitrate Reductase Assay (NRA), Malachite Green Decolorization Assay (MGDA), and Crystal Violet Decolorization Assay (CVDA) methods were included in the study. In addition, mutations in the pncA gene were investigated using sequence analysis in PZA-resistant isolates. Results: As a result of the comparison of the colorimetric methods with the reference method, agreement was determined as 93.3% in REMA and NRA, 90% in MGDA, and 93.3% in CVDA. In 13 of 15 resistant isolates, the pncA gene mutation was detected by sequence analysis. Conclusions: As a result of the work, the results from the colorimetric methods were found to be at a high level of concordance with the reference method. They are also inexpensive and easily applicable methods.


Assuntos
Colorimetria/métodos , Farmacorresistência Bacteriana Múltipla , Mycobacterium tuberculosis/efeitos dos fármacos , Pirazinamida/farmacologia , Amidoidrolases/genética , Genótipo , Humanos , Testes de Sensibilidade Microbiana , Mutação/efeitos dos fármacos , Mycobacterium tuberculosis/genética , Oxazinas/farmacologia , Análise de Sequência de DNA , Tuberculose Resistente a Múltiplos Medicamentos/microbiologia , Xantenos/farmacologia
19.
Phytomedicine ; 78: 153306, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32854039

RESUMO

BACKGROUND: Gambogenic acid (GNA), an active component of Garcinia hanburyi Hook.f. (Clusiaceae) (common name gamboge), exerts anti-inflammatory and antitumor properties. However, the underlying mechanism of GNA in colorectal cancer (CRC) is still not well understood. PURPOSE: This study aimed to investigate the antitumor effects and mechanisms of GNA on CRC in vitro and in vivo. METHODS: Cell viability, colony formation and cell apoptosis assays were performed to determine the antitumor effects of GNA. qRT-PCR and Western blotting were performed to evaluate the expression of genes or proteins affected by GNA in vitro and in vivo. HCT116 colon cancer xenografts and the APCmin/+ mice model were used to confirm the antitumor effects of GNA on CRC in vivo. RESULTS: GNA induced Noxa-mediated apoptosis by inducing reactive oxygen species (ROS) generation and c-Jun N-terminal kinase (JNK) activation. Moreover, GNA triggered endoplasmic reticulum (ER) stress, which subsequently activated inositol-requiring enzyme-1α (IRE1α) leading to JNK phosphorylation. ROS scavenger attenuated GNA-induced IRE1α activation and JNK phosphorylation. Knockdown of IRE1α also prevented GNA-induced JNK phosphorylation. In vivo, GNA suppressed tumor growth and progression in HCT116 colon cancer xenografts and the APCmin/+ mices model. CONCLUSION: These findings revealed that GNA induced Noxa-mediated apoptosis by activating the ROS/IRE1α/JNK signaling pathway in CRC both in vitro and in vivo. GNA is therefore a promising antitumor agent for CRC treatment.


Assuntos
Neoplasias Colorretais/tratamento farmacológico , Endorribonucleases/metabolismo , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Xantenos/farmacologia , Animais , Antineoplásicos Fitogênicos/farmacologia , Apoptose/efeitos dos fármacos , Apoptose/fisiologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Feminino , Humanos , Camundongos Endogâmicos BALB C , Proteínas Proto-Oncogênicas c-bcl-2/genética , Espécies Reativas de Oxigênio/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
20.
Mol Neurobiol ; 57(10): 4305-4321, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32700252

RESUMO

Buyang Huanwu Decoction (BHD), a classic traditional Chinese medicine (TCM) formula, has been used for recovering neurological dysfunctions and treating post-stroke disability in China for 200 years. In the present study, we investigated the effects of BHD on inhibiting neuronal apoptosis, promoting proliferation and differentiation of neural stem cells (NSCs) and neurite formation and enhancing learning and memory functional recovery in an experimental rat ischemic stroke model. BHD significantly reduced infarct volume and decreased cell apoptosis in the ischemic brain. BHD enhanced neuronal cell viability in vitro. BHD dose-dependently promoted the proliferation of NSCs in ischemic rat brains in vivo. Moreover, BHD promoted neuronal and astrocyte differentiation in primary cultured NSCs in vitro. Water maze test revealed that BHD promoted the recovery of learning function but not memory functions in the transient ischemic rats. We then investigated the changes of the cellular signaling molecules by using two-dimension (2D) gel electrophoresis and focused on the PI3K/Akt/Bad and Jak2/Stat3/cyclin D1signaling pathway to uncover its underlying mechanisms for its neuroprotective and neurogenetic effects. BHD significantly upregulated the expression of p-PI3K, p-Akt, and p-Bad as well as the expression of p-Jak, p-Stat3, and cyclin D1 in vitro and in vivo. In addition, BHD upregulated Hes1 and downregulated cav-1 in vitro and in vivo. Taken together, these results suggest that BHD has neuroprotective effects and neurogenesis-promoting effects via activating PI3K/Akt/Bad and Jak2/Stat3/Cyclin D1 signaling pathways. Graphical Abstract Buyang Huanwu Decoction (BHD) activates the PI3K-AKT-BAD pathway in the ischemic brain for neuroprotection. BHD also activates JAK2/STAT3/Cyclin D1 signaling cascades for promoting neurogenesis in the hippocampus of post-ischemic brains. Moreover, BHD inhibits the expression of caveolin-1 and increases the expression of HES1 for promoting neuronal differentiation. The neuroprotective and neurogenesis-promoting effects in the hippocampus of post-ischemic brains promote learning ability.


Assuntos
Medicamentos de Ervas Chinesas/uso terapêutico , Ataque Isquêmico Transitório/tratamento farmacológico , AVC Isquêmico/tratamento farmacológico , Neurogênese , Fármacos Neuroprotetores/uso terapêutico , Proteômica , Transdução de Sinais , Proteínas 14-3-3/metabolismo , Animais , Apoptose/efeitos dos fármacos , Astrócitos/efeitos dos fármacos , Astrócitos/metabolismo , Astrócitos/patologia , Axônios/patologia , Caveolina 1/metabolismo , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Ciclina D1/metabolismo , Regulação para Baixo/efeitos dos fármacos , Medicamentos de Ervas Chinesas/farmacologia , Receptores ErbB/metabolismo , Ataque Isquêmico Transitório/complicações , Ataque Isquêmico Transitório/patologia , Ataque Isquêmico Transitório/fisiopatologia , AVC Isquêmico/complicações , AVC Isquêmico/patologia , AVC Isquêmico/fisiopatologia , Janus Quinase 2/metabolismo , Masculino , Memória/efeitos dos fármacos , Células-Tronco Neurais/efeitos dos fármacos , Células-Tronco Neurais/patologia , Neurite (Inflamação)/patologia , Neurogênese/efeitos dos fármacos , Neuroproteção/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Células PC12 , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ratos , Ratos Sprague-Dawley , Recuperação de Função Fisiológica/efeitos dos fármacos , Traumatismo por Reperfusão/complicações , Traumatismo por Reperfusão/tratamento farmacológico , Traumatismo por Reperfusão/patologia , Fator de Transcrição STAT3/metabolismo , Fatores de Transcrição HES-1/metabolismo , Regulação para Cima/efeitos dos fármacos , Xantenos/farmacologia , Proteína de Morte Celular Associada a bcl/metabolismo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...