Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 1.339
Filtrar
1.
IET Nanobiotechnol ; 15(7): 627-637, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34695297

RESUMO

Infection with human immunodeficiency virus (HIV)-1 causes immunological disorders and death worldwide which needs to be further assisted by novel anti-retroviral drug delivery systems. Consequently, finding newer anti-retroviral pharmaceuticals by using biocompatible, biodegradable nanomaterials comprising a nanoparticle as core and a therapeutic agent is of high global interest. In this experiment, a second generation of a negatively charged nano-biopolymer linear globular G2 dendrimer was carefully conjugated and loaded with well-known anti-HIV drugs lamivudine and efavirenz, respectively. They were characterised by a variety of analytical methods such as Zetasizer, Fourier-transform infrared spectroscopy, elemental analysis and liquid chromatography-mass spectroscopy. Additionally, conjugated lamivudine and loaded efazirenz with globular PEGylated G2 dendrimer were tested on an HEK293 T cell infected by single-cycle replicable HIV-1 virion and evaluated using XTT test and HIV-1 P24 protein load. The results showed that lamivudine-conjugated G2 significantly decreased retroviral activity without any cell toxicity. This effect was more or less observed by efavirenz-loaded G2. These nano-constructs are strongly suggested for further in vivo anti-HIV assays.


Assuntos
Dendrímeros , Lamivudina , Alcinos , Benzoxazinas/farmacologia , Ciclopropanos , Sistemas de Liberação de Medicamentos , Células HEK293 , Humanos , Lamivudina/farmacologia
2.
J Med Microbiol ; 70(10)2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34668851

RESUMO

Introduction. Biofilm formation and hemolysis are closely related to the pathogenicity of Staphylococcus aureus.Hypothesis/Gap Statement. Strategies that reduce the mortality of S. aureus infections may involve novel antimicrobials and/or drugs that decrease S. aureus virulence, such as biofilm formation. The antiviral drug efavirenz is a non-nucleoside reverse transcriptase inhibitor, which also has shown antibacterial effect on Bacillus subtilis and Escherichia coli. Its effect on pathogen virulence has not yet been explored.Aim. This study investigates the antimicrobial and anti-virulence effect of efavirenz on S. aureus.Methodology. Biofilm biomasses were detected by crystal violet staining. Hemolysis activities of S. aureus were determined by rabbit erythrocytes lysis assay. RNA levels of transcriptional regulatory genes, biofilm-related genes, and virulence-related genes of S. aureus were determined by RT-qPCR.Results. Efavirenz showed an inhibitory effect on the growth of S. aureus, Enterococcus faecalis and Streptococcus agalactiae at 50 µM. Efavirenz significantly inhibited biofilm formation of both methicillin-sensitive S. aureus (MSSA) and methicillin-resistant S. aureus (MRSA) at 25 µM, but did not affect the growth of planktonic S. aureus cells. Moreover, hemolysis by S. aureus was inhibited by efavirenz at 25 µM. The expression levels of RNA transcriptional regulatory genes (agrA, agrC, sigB, saeR and saeS), biofilm-related genes (cidA, clfA, clfB, fnbA, fnbB), and virulence-related genes (hla, hld, staphopain B, alpha-3 PSM, beta PSM, delta PSM) of S. aureus decreased significantly at 25 µM efavirenz.Conclusion. Efavirenz inhibits S. aureus biofilm formation and virulence in vitro.


Assuntos
Alcinos/farmacologia , Antibacterianos/farmacologia , Benzoxazinas/farmacologia , Biofilmes/efeitos dos fármacos , Ciclopropanos/farmacologia , Infecções Estafilocócicas/tratamento farmacológico , Staphylococcus aureus/efeitos dos fármacos , Virulência/efeitos dos fármacos
3.
Molecules ; 26(20)2021 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-34684770

RESUMO

The Sterling Research Group identified pravadoline as an aminoalkylindole (AAI) non-steroidal anti-inflammatory pain reliever. As drug design progressed, the ability of AAI analogs to block prostaglandin synthesis diminished, and antinociceptive activity was found to result from action at the CB1 cannabinoid receptor, a G-protein-coupled receptor (GPCR) abundant in the brain. Several laboratories applied computational chemistry methods to ultimately conclude that AAI and cannabinoid ligands could overlap within a common binding pocket but that WIN55212-2 primarily utilized steric interactions via aromatic stacking, whereas cannabinoid ligands required some electrostatic interactions, particularly involving the CB1 helix-3 lysine. The Huffman laboratory identified strategies to establish CB2 receptor selectivity among cannabimimetic indoles to avoid their CB1-related adverse effects, thereby stimulating preclinical studies to explore their use as anti-hyperalgesic and anti-allodynic pharmacotherapies. Some AAI analogs activate novel GPCRs referred to as "Alkyl Indole" receptors, and some AAI analogs act at the colchicine-binding site on microtubules. The AAI compounds having the greatest potency to interact with the CB1 receptor have found their way into the market as "Spice" or "K2". The sale of these alleged "herbal products" evades FDA consumer protections for proper labeling and safety as a medicine, as well as DEA scheduling as compounds having no currently accepted medical use and a high potential for abuse. The distribution to the public of potent alkyl indole synthetic cannabimimetic chemicals without regard for consumer safety contrasts with the adherence to regulatory requirements for demonstration of safety that are routinely observed by ethical pharmaceutical companies that market medicines.


Assuntos
Canabinoides/química , Canabinoides/farmacologia , Drogas Desenhadas/química , Drogas Desenhadas/farmacologia , Analgésicos/química , Analgésicos/farmacologia , Animais , Benzoxazinas/farmacologia , Sítios de Ligação , Materiais Biomiméticos/química , Materiais Biomiméticos/farmacologia , Desenho de Fármacos , Humanos , Indóis/química , Indóis/farmacologia , Ligantes , Morfolinas/farmacologia , Naftalenos/farmacologia , Receptor CB1 de Canabinoide/agonistas , Receptor CB1 de Canabinoide/química , Receptor CB2 de Canabinoide/agonistas , Receptor CB2 de Canabinoide/química , Eletricidade Estática , Relação Estrutura-Atividade
4.
Life Sci ; 285: 119993, 2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34592231

RESUMO

AIMS: Characterizing cannabinoid receptors (CBRs) expressed in Ewing sarcoma (EWS) cell lines as potential targets for anti-cancer drug development. MAIN METHODS: CBR affinity and function were examined by competitive binding and G-protein activation, respectively. Cannabinoid-mediated cytotoxicity and cell viability were evaluated by LDH, and trypan blue assays, respectively. KEY FINDINGS: qRT-PCR detected CB1 (CB1R) and CB2 receptor (CB2R) mRNA in TC-71 cells. However, binding screens revealed that CBRs expressed exhibit atypical properties relative to canonical receptors, because specific binding in TC-71 could only be demonstrated by the established non-selective CB1/CB2R radioligand [3H]WIN-55,212-2, but not CB1/CB2R radioligand [3H]CP-55,940. Homologous receptor binding demonstrated that [3H]WIN-55,212-2 binds to a single site with nanomolar affinity, expressed at high density. Further support for non-canonical CBRs expression is provided by subsequent binding screens, revealing that only 9 out of 28 well-characterized cannabinoids with high affinity for canonical CB1 and/or CB2Rs were able to displace [3H]WIN-55,212-2, whereas two ligands enhanced [3H]WIN-55,212-2 binding. Five cannabinoids producing the greatest [3H]WIN-55,212-2 displacement exhibited high nanomolar affinity (Ki) for expressed receptors. G-protein modulation and adenylyl cyclase assays further indicate that these CBRs exhibit distinct signaling/functional profiles compared to canonical CBRs. Importantly, cannabinoids with the highest affinity for non-canonical CBRs reduced TC-71 viability and induced cytotoxicity in a time-dependent manner. Studies in a second EWS cell line (A-673) showed similar atypical binding properties of expressed CBRs, and cannabinoid treatment produced cytotoxicity. SIGNIFICANCE: Cannabinoids induce cytotoxicity in EWS cell lines via non-canonical CBRs, which might be a potential therapeutic target to treat EWS.


Assuntos
Antineoplásicos/farmacologia , Benzoxazinas/farmacologia , Canabinoides/farmacologia , Morfolinas/farmacologia , Naftalenos/farmacologia , Receptor CB1 de Canabinoide/metabolismo , Receptor CB2 de Canabinoide/metabolismo , Sarcoma de Ewing/metabolismo , Ligação Competitiva , Linhagem Celular Tumoral , Citotoxinas/farmacologia , Desenvolvimento de Medicamentos , Humanos , Ligantes , Receptor CB1 de Canabinoide/agonistas , Receptor CB2 de Canabinoide/agonistas
5.
Sci Rep ; 11(1): 16801, 2021 08 19.
Artigo em Inglês | MEDLINE | ID: mdl-34413352

RESUMO

The lymphatic network of mammalian heart is an important regulator of interstitial fluid compartment and immune cell trafficking. We observed a remodeling of the cardiac lymphatic vessels and a reduced lymphatic efficiency during heart hypertrophy and failure induced by transverse aortic constriction. The lymphatic endothelial cell number of the failing hearts was positively correlated with cardiac function and with a subset of cardiac macrophages. This macrophage population distinguished by LYVE-1 (Lymphatic vessel endothelial hyaluronic acid receptor-1) and by resident macrophage gene expression signature, appeared not replenished by CCR2 mediated monocyte infiltration during pressure overload. Isolation of macrophage subpopulations showed that the LYVE-1 positive subset sustained in vitro and in vivo lymphangiogenesis through the expression of pro-lymphangiogenic factors. In contrast, the LYVE-1 negative macrophage subset strongly expressed MMP12 and decreased the endothelial LYVE-1 receptors in lymphatic endothelial cells, a feature of cardiac lymphatic remodeling in failing hearts. The treatment of mice with a CCR2 antagonist during pressure overload modified the proportion of macrophage subsets within the pathological heart and preserved lymphatic network from remodeling. This study reports unknown and differential functions of macrophage subpopulations in the regulation of cardiac lymphatic during pathological hypertrophy and may constitute a key mechanism underlying the progression of heart failure.


Assuntos
Vasos Linfáticos/metabolismo , Macrófagos/metabolismo , Miocárdio/patologia , Pressão , Animais , Benzoxazinas/farmacologia , Células CHO , Polaridade Celular/efeitos dos fármacos , Cricetulus , Eletrocardiografia , Células Endoteliais/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Linfangiogênese/efeitos dos fármacos , Vasos Linfáticos/efeitos dos fármacos , Macrófagos/efeitos dos fármacos , Masculino , Camundongos Endogâmicos C57BL , Monócitos/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptores CCR2/metabolismo , Compostos de Espiro/farmacologia , Transcriptoma , Proteínas de Transporte Vesicular/metabolismo
6.
Int J Mol Sci ; 22(15)2021 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-34360704

RESUMO

The activation of the endocannabinoid system controls the release of many neurotransmitters involved in the brain reward pathways, including glutamate. Both endocannabinoid and glutamate systems are crucial for alcohol relapse. In the present study, we hypothesize that N-methyl-D-aspartate (NMDA) glutamate receptors regulate the ability of a priming dose of WIN 55,212-2 to cross-reinstate ethanol-induced conditioned place preference (CPP). To test this hypothesis, ethanol-induced (1.0 g/kg, 10% w/v, i.p.) CPP (unbiased method) was established using male adult Wistar rats. After CPP extinction, one group of animals received WIN 55,212-2 (1.0 and 2.0 mg/kg, i.p.), the cannabinoid receptor 1 (CB1) agonist, or ethanol, and the other group received memantine (3.0 or 10 mg/kg, i.p.), the NMDA antagonist and WIN 55,212-2 on the reinstatement day. Our results showed that a priming injection of WIN 55,212-2 (2.0 mg/kg, i.p.) reinstated (cross-reinstated) ethanol-induced CPP with similar efficacy to ethanol. Memantine (3.0 or 10 mg/kg, i.p.) pretreatment blocked this WIN 55,212-2 effect. Furthermore, our experiments indicated that ethanol withdrawal (7 days withdrawal after 10 days ethanol administration) down-regulated the CNR1 (encoding CB1), GRIN1/2A (encoding GluN1 and GluN2A subunit of the NMDA receptor) genes expression in the prefrontal cortex and dorsal striatum, but up-regulated these in the hippocampus, confirming the involvement of these receptors in ethanol rewarding effects. Thus, our results show that the endocannabinoid system is involved in the motivational properties of ethanol, and glutamate may control cannabinoid induced relapse into ethanol seeking behavior.


Assuntos
Benzoxazinas/farmacologia , Condicionamento Psicológico/efeitos dos fármacos , Etanol/farmacologia , Memantina/farmacologia , Morfolinas/farmacologia , Motivação/efeitos dos fármacos , Naftalenos/farmacologia , Animais , Masculino , Ratos , Ratos Wistar
7.
Front Immunol ; 12: 639378, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34093527

RESUMO

Microglia, the resident brain phagocytes, likely play a key role in human immunodeficiency virus (HIV) infection of the central nervous system (CNS) and subsequent neuropathogenesis; however, the nature of the infection-induced changes that yield damaging CNS effects and the stimuli that provoke microglial activation remains elusive, especially in the current era of using antiretroviral (ARV) drugs for ARV therapy (ART). Altered microglial metabolism can modulate cellular functionality and pathogenicity in neurological disease. While HIV infection itself alters brain energy metabolism, the effect of ARV drugs, particularly those currently used in treatment, on metabolism is understudied. Dolutegravir (DTG) and emtricitabine (FTC) combination, together with tenofovir (TAF or TDF), is one of the recommended first line treatments for HIV. Despite the relatively good tolerability and safety profile of FTC, a nucleoside reverse transcriptase inhibitor, and DTG, an integrase inhibitor, adverse side effects have been reported and highlight a need to understand off-target effects of these medications. We hypothesized that similar to previous ART regimen drugs, DTG and FTC side effects involve mitochondrial dysfunction. To increase detection of ARV-induced mitochondrial effects, highly glycolytic HeLa epithelial cells were forced to rely on oxidative phosphorylation by substituting galactose for glucose in the growth media. We assessed ATP levels, resazurin oxidation-reduction (REDOX), and mitochondrial membrane potential following 24-hour exposure (to approximate effects of one dose equivalent) to DTG, FTC, and efavirenz (EFV, a known mitotoxic ARV drug). Further, since microglia support productive HIV infection, act as latent HIV cellular reservoirs, and when dysfunctional likely contribute to HIV-associated neurocognitive disorders, the experiments were repeated using BV2 microglial cells. In HeLa cells, FTC decreased mitochondrial REDOX activity, while DTG, similar to EFV, impaired both mitochondrial ATP generation and REDOX activity. In contrast to HeLa cells, DTG increased cellular ATP generation and mitochondrial REDOX activity in BV2 cells. Bioenergetic analysis revealed that DTG, FTC, and EFV elevated BV2 cell mitochondrial respiration. DTG and FTC exposure induced distinct mitochondrial functional changes in HeLa and BV2 cells. These findings suggest cell type-specific metabolic changes may contribute to the toxic side effects of these ARV drugs.


Assuntos
Alcinos/farmacologia , Fármacos Anti-HIV/farmacologia , Benzoxazinas/farmacologia , Ciclopropanos/farmacologia , Emtricitabina/farmacologia , Células Epiteliais/efeitos dos fármacos , Infecções por HIV/tratamento farmacológico , Compostos Heterocíclicos com 3 Anéis/farmacologia , Microglia/efeitos dos fármacos , Oxazinas/farmacologia , Piperazinas/farmacologia , Piridonas/farmacologia , Trifosfato de Adenosina/metabolismo , Linhagem Celular Tumoral , Células Epiteliais/metabolismo , Infecções por HIV/metabolismo , Infecções por HIV/virologia , HIV-1/efeitos dos fármacos , Células HeLa , Humanos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Microglia/metabolismo , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Oxazinas/metabolismo , Inibidores da Transcriptase Reversa/farmacologia , Latência Viral/efeitos dos fármacos , Xantenos/metabolismo
8.
Cancer Chemother Pharmacol ; 88(3): 369-377, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34019108

RESUMO

PURPOSE: Fedratinib is an oral and selective Janus kinase 2 inhibitor that is indicated for treatment of adults with intermediate-2 or high-risk primary or secondary myelofibrosis. Fedratinib is metabolized by cytochrome P450s (CYPs), primarily CYP3A4. The objective of this study was to determine the effects of the strong CYP3A4 inducer rifampin and moderate CYP3A4 inducer efavirenz on the pharmacokinetics of single doses of fedratinib. METHODS: This Phase 1, open-label, two-part study (Part 1 for rifampin and Part 2 for efavirenz) was conducted in healthy adult men and women. A single dose of fedratinib (500 mg) was administered on Day 1. Participants received rifampin 600 mg daily or efavirenz 600 mg daily on Days 9-18. On Day 17, a single dose of fedratinib (500 mg) was coadministered with rifampin or efavirenz. Plasma fedratinib concentrations were measured using validated liquid chromatography-tandem mass spectrometry. RESULTS: Maximum observed plasma fedratinib concentrations were lowered by approximately 70% and 30% during coadministration with rifampin or efavirenz, respectively, compared with fedratinib alone. Geometric means of fedratinib area under the plasma concentration-time curve from 0 to infinity were decreased by 81% (90% confidence interval [CI], 77-83%) and 47% (90% CI, 40-53%) during coadministration with rifampin or efavirenz, respectively. Fedratinib was generally well tolerated when administered alone or in combination with rifampin or efavirenz. CONCLUSION: Significant reductions in fedratinib exposure were observed in the presence of strong or moderate CYP3A4 inducers. These results suggest that agents that are strong or moderate inducers of CYP3A4 should be avoided when coadministered with fedratinib. TRIAL REGISTRATION NUMBER: NCT03983239 (Registration date: June 12, 2019).


Assuntos
Indutores do Citocromo P-450 CYP3A/farmacologia , Inibidores de Proteínas Quinases/farmacocinética , Pirrolidinas/farmacocinética , Sulfonamidas/farmacocinética , Adulto , Alcinos/farmacologia , Área Sob a Curva , Benzoxazinas/farmacologia , Cromatografia Líquida , Ciclopropanos/farmacologia , Interações Medicamentosas , Feminino , Humanos , Janus Quinase 2/antagonistas & inibidores , Masculino , Pessoa de Meia-Idade , Inibidores de Proteínas Quinases/efeitos adversos , Pirrolidinas/efeitos adversos , Rifampina/farmacologia , Sulfonamidas/efeitos adversos , Espectrometria de Massas em Tandem , Adulto Jovem
9.
Nat Commun ; 12(1): 2500, 2021 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-33947853

RESUMO

Reverse transcription of the HIV-1 viral RNA genome (vRNA) is an integral step in virus replication. Upon viral entry, HIV-1 reverse transcriptase (RT) initiates from a host tRNALys3 primer bound to the vRNA genome and is the target of key antivirals, such as non-nucleoside reverse transcriptase inhibitors (NNRTIs). Initiation proceeds slowly with discrete pausing events along the vRNA template. Despite prior medium-resolution structural characterization of reverse transcriptase initiation complexes (RTICs), higher-resolution structures of the RTIC are needed to understand the molecular mechanisms that underlie initiation. Here we report cryo-EM structures of the core RTIC, RTIC-nevirapine, and RTIC-efavirenz complexes at 2.8, 3.1, and 2.9 Å, respectively. In combination with biochemical studies, these data suggest a basis for rapid dissociation kinetics of RT from the vRNA-tRNALys3 initiation complex and reveal a specific structural mechanism of nucleic acid conformational stabilization during initiation. Finally, our results show that NNRTIs inhibit the RTIC and exacerbate discrete pausing during early reverse transcription.


Assuntos
Transcriptase Reversa do HIV/química , HIV-1/efeitos dos fármacos , RNA de Transferência de Lisina/química , RNA Viral/química , Inibidores da Transcriptase Reversa/química , Alcinos/química , Alcinos/farmacologia , Benzoxazinas/química , Benzoxazinas/farmacologia , Domínio Catalítico , Microscopia Crioeletrônica , Ciclopropanos/química , Ciclopropanos/farmacologia , Transcriptase Reversa do HIV/genética , Transcriptase Reversa do HIV/metabolismo , HIV-1/enzimologia , HIV-1/genética , HIV-1/metabolismo , Modelos Moleculares , Nevirapina/química , Nevirapina/farmacologia , Conformação de Ácido Nucleico/efeitos dos fármacos , RNA de Transferência de Lisina/genética , RNA Viral/genética , Inibidores da Transcriptase Reversa/farmacologia
10.
Biomed Res Int ; 2021: 6612592, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33977107

RESUMO

Glioblastoma is a highly invasive primary malignant tumor of the central nervous system. Cannabinoid analogue WIN 55,212-2 (WIN) exhibited a novel anticancer effect against human tumors. However, the anticancer potential and underlying mechanism of WIN against human glioma remain unclear. Herein, the anticancer efficiency and mechanism of WIN in U251 human glioma cells were investigated. The results showed that WIN dose-dependently inhibited U251 cell proliferation, migration, and invasion in vitro. WIN treatment also effectively suppressed U251 tumor spheroids growth ex vivo. Further studies found that WIN induced significant apoptosis as convinced by the caspase-3 activation and release of cytochrome C. Mechanism investigation revealed that WIN triggered ROS-mediated DNA damage and caused dysfunction of VEGF-AKT/FAK signal axis. However, ROS inhibition effectively attenuated WIN-induced DNA damage and dysfunction of VEGF-AKT/FAK signal axis and eventually improved U251 cell proliferation, migration, and invasion. Taken together, our findings validated that WIN had the potential to inhibit U251 cell proliferation, migration, and invasion and induce apoptosis by triggering ROS-dependent DNA damage and dysfunction of VEGF-AKT/FAK signal axis.


Assuntos
Benzoxazinas/farmacologia , Glioma/metabolismo , Morfolinas/farmacologia , Naftalenos/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacos , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Dano ao DNA/efeitos dos fármacos , Humanos
11.
Angew Chem Int Ed Engl ; 60(32): 17514-17521, 2021 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-34018657

RESUMO

Macrophage migration inhibitory factor (MIF) is involved in protein-protein interactions that play key roles in inflammation and cancer. Current strategies to develop small molecule modulators of MIF functions are mainly restricted to the MIF tautomerase active site. Here, we use this site to develop proteolysis targeting chimera (PROTAC) in order to eliminate MIF from its protein-protein interaction network. We report the first potent MIF-directed PROTAC, denoted MD13, which induced almost complete MIF degradation at low micromolar concentrations with a DC50 around 100 nM in A549 cells. MD13 suppresses the proliferation of A549 cells, which can be explained by deactivation of the MAPK pathway and subsequent induction of cell cycle arrest at the G2/M phase. MD13 also exhibits antiproliferative effect in a 3D tumor spheroid model. In conclusion, we describe the first MIF-directed PROTAC (MD13) as a research tool, which also demonstrates the potential of PROTACs in cancer therapy.


Assuntos
Antineoplásicos/farmacologia , Benzoxazinas/farmacologia , Oxirredutases Intramoleculares/metabolismo , Fatores Inibidores da Migração de Macrófagos/metabolismo , Ftalimidas/farmacologia , Células A549 , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Antineoplásicos/síntese química , Benzoxazinas/síntese química , Proliferação de Células/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Pontos de Checagem da Fase G2 do Ciclo Celular/efeitos dos fármacos , Humanos , Oxirredutases Intramoleculares/química , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Fatores Inibidores da Migração de Macrófagos/química , Ftalimidas/síntese química , Proteólise/efeitos dos fármacos , Esferoides Celulares/efeitos dos fármacos , Ubiquitina-Proteína Ligases/metabolismo
12.
Acta Neuropathol Commun ; 9(1): 58, 2021 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-33795005

RESUMO

Prion diseases are fatal, infectious, and incurable neurodegenerative disorders caused by misfolding of the cellular prion protein (PrPC) into the infectious isoform (PrPSc). In humans, there are sporadic, genetic and infectious etiologies, with sporadic Creutzfeldt-Jakob disease (sCJD) being the most common form. Currently, no treatment is available for prion diseases. Cellular cholesterol is known to impact prion conversion, which in turn results in an accumulation of cholesterol in prion-infected neurons. The major elimination of brain cholesterol is achieved by the brain specific enzyme, cholesterol 24-hydroxylase (CYP46A1). Cyp46A1 converts cholesterol into 24(S)-hydroxycholesterol, a membrane-permeable molecule that exits the brain. We have demonstrated for the first time that Cyp46A1 levels are reduced in the brains of prion-infected mice at advanced disease stage, in prion-infected neuronal cells and in post-mortem brains of sCJD patients. We have employed the Cyp46A1 activator efavirenz (EFV) for treatment of prion-infected neuronal cells and mice. EFV is an FDA approved anti-HIV medication effectively crossing the blood brain barrier and has been used for decades to chronically treat HIV patients. EFV significantly mitigated PrPSc propagation in prion-infected cells while preserving physiological PrPC and lipid raft integrity. Notably, oral administration of EFV treatment chronically at very low dosage starting weeks to months after intracerebral prion inoculation of mice significantly prolonged the lifespan of animals. In summary, our results suggest that Cyp46A1 as a novel therapeutic target and that its activation through repurposing the anti-retroviral medication EFV might be valuable treatment approach for prion diseases.


Assuntos
Alcinos/farmacologia , Benzoxazinas/farmacologia , Colesterol 24-Hidroxilase/metabolismo , Síndrome de Creutzfeldt-Jakob/metabolismo , Ciclopropanos/farmacologia , Inibidores das Enzimas do Citocromo P-450/farmacologia , Proteínas PrPSc/efeitos dos fármacos , Administração Oral , Animais , Colesterol 24-Hidroxilase/efeitos dos fármacos , Reposicionamento de Medicamentos , Humanos , Microdomínios da Membrana/metabolismo , Camundongos , Proteínas PrPC/efeitos dos fármacos , Proteínas PrPC/metabolismo , Proteínas PrPSc/metabolismo
13.
J Med Chem ; 64(9): 5838-5849, 2021 05 13.
Artigo em Inglês | MEDLINE | ID: mdl-33876629

RESUMO

Sirtuins are signaling hubs orchestrating the cellular response to various stressors with roles in all major civilization diseases. Sirtuins remove acyl groups from lysine residues of proteins, thereby controlling their activity, turnover, and localization. The seven human sirtuins, SirT1-7, are closely related in structure, hindering the development of specific inhibitors. Screening 170,000 compounds, we identify and optimize SirT1-specific benzoxazine inhibitors, Sosbo, which rival the efficiency and surpass the selectivity of selisistat (EX527). The compounds inhibit the deacetylation of p53 in cultured cells, demonstrating their ability to permeate biological membranes. Kinetic analysis of inhibition and docking studies reveal that the inhibitors bind to a complex of SirT1 and nicotinamide adenine dinucleotide, similar to selisistat. These new SirT1 inhibitors are valuable alternatives to selisistat in biochemical and cell biological studies. Their greater selectivity may allow the development of better targeted drugs to combat SirT1 activity in diseases such as cancer, Huntington's chorea, or anorexia.


Assuntos
Benzoxazinas/química , Sirtuína 1/antagonistas & inibidores , Acetilação/efeitos dos fármacos , Amidas/química , Benzoxazinas/metabolismo , Benzoxazinas/farmacologia , Sítios de Ligação , Carbazóis/química , Carbazóis/metabolismo , Linhagem Celular Tumoral , Avaliação Pré-Clínica de Medicamentos , Humanos , Concentração Inibidora 50 , Cinética , Simulação de Acoplamento Molecular , NAD/química , NAD/metabolismo , Isoformas de Proteínas/antagonistas & inibidores , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/química , Proteínas Recombinantes/isolamento & purificação , Sirtuína 1/genética , Sirtuína 1/metabolismo , Relação Estrutura-Atividade , Proteína Supressora de Tumor p53/metabolismo
14.
J Bone Joint Surg Am ; 103(11): 984-991, 2021 06 02.
Artigo em Inglês | MEDLINE | ID: mdl-33759484

RESUMO

BACKGROUND: After spinal surgery and other orthopaedic procedures, most patients receive opioids for pain, leading to potential complications such as pseudarthrosis and opioid abuse associated with long-term use. As an alternative, the endocannabinoid system has been shown to have antinociceptive activity, while contributing to bone homeostasis via the CB1 and CB2 cannabinoid receptors. This study evaluates the impact of the cannabinoid receptor agonist WIN55,212-2 (WIN55) on osteogenic differentiation in vitro as well as bone regeneration and spinal fusion in a preclinical rat model. METHODS: Primary rat bone marrow stromal cells were cultured in standard or osteogenic media and exposed to vehicle alone or WIN55. Runx2 and Alkaline phosphatase (Alpl) were quantified via qPCR (quantitative real-time polymerase chain reaction), followed by assessment of ALP activity and matrix mineralization. For in vivo evaluation, 45 female Sprague Dawley rats (n = 15 per group) underwent L4-L5 posterolateral spinal fusion with bilateral placement of collagen scaffolds preloaded with low-dose rhBMP-2 (recombinant human bone morphogenetic protein-2; 0.5 µg/implant). Postoperatively, rats received the vehicle alone or 0.5 or 2.5 mg/kg WIN55 via daily intraperitoneal injections for 5 days. Bone regeneration and spinal fusion were assessed using radiography, manual palpation-based fusion scoring, microcomputed tomography imaging, and histology. RESULTS: mRNA expression levels of Runx2 and Alp were similar among cells treated with vehicle alone and WIN55. Likewise, exposure to WIN55 did not inhibit ALP activity or bone matrix mineralization. In this animal model, no significant differences were found among groups with regard to mean fusion score, fusion rate, or new bone volume. CONCLUSIONS: WIN55 showed no adverse impact on osteogenic differentiation, bone regeneration, and spinal fusion. This supports that cannabinoid receptor agonists should be further investigated as a potential alternative approach for postoperative analgesia following spinal fusion and other orthopaedic procedures requiring bone-healing. CLINICAL RELEVANCE: The identification of alternative treatments for postoperative pain following orthopaedic surgical procedures is crucial in combating the ongoing opioid abuse crisis. The endocannabinoid system may represent a viable alternative target for addressing orthopaedic postoperative pain.


Assuntos
Benzoxazinas/farmacologia , Regeneração Óssea/efeitos dos fármacos , Agonistas de Receptores de Canabinoides/farmacologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Morfolinas/farmacologia , Naftalenos/farmacologia , Osteogênese/efeitos dos fármacos , Fusão Vertebral , Animais , Proteína Morfogenética Óssea 2/administração & dosagem , Feminino , Vértebras Lombares/diagnóstico por imagem , Vértebras Lombares/cirurgia , Período Pós-Operatório , Ratos , Ratos Sprague-Dawley , Proteínas Recombinantes/administração & dosagem , Tecidos Suporte , Tomografia Computadorizada por Raios X , Fator de Crescimento Transformador beta/administração & dosagem
15.
Psychopharmacology (Berl) ; 238(6): 1657-1669, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33715044

RESUMO

RATIONALE: Nucleus cuneiformis (NC), a reticular nucleus of the midbrain, is a part of the descending pain modulatory system and therefore has an important role in pain perception. OBJECTIVES: Considering the abundance of GABAA and cannabinoid receptors in the NC and also the bidirectional roles for GABA in controlling nociception, the present study examined the effects of bilateral intra-NC microinjection of different doses of the GABAA receptor agonist, muscimol, and the GABAA receptor antagonist, bicuculline, on pain modulation using formalin test. We also assessed interaction between canabinergic and GABAergic systems in the NC during this test. METHODS: Rats were exposed to intra-NC microinjection of bicuculline (50,100, and 200 ng/side) or muscimol (60, 120, and 240 ng/side) and then subjected to the formalin test. In another set of experiments, the effects of muscimol (60 ng/side) or bicuculline (50 ng/side) administration 5 min before a cannabinoid receptor agonist WIN 55,212-2 (5, 10, and 20 µg/side) microinjection into NC on the formalin test were evaluated. RESULTS: Microinjection of bicuculline and muscimol into the NC decreased and increased pain responses, respectively, in a dose-dependent manner during both phases of the test. Microinjection of WIN 55,212-2 into the NC significantly reduced pain responses in a dose-dependent manner. Microinjection of bicuculline or muscimol in combination with WIN 55,212-2 into the NC respectively potentiated and attenuated WIN 55,212-2-induced antinociception in the formalin test. CONCLUSIONS: This study shows that GABA in the NC is involved in pain modulation and suggests the existence of a GABAA-mediated inhibitory system in the NC on pain control. Furthermore, it seems that the antinociceptive effect of WIN 55,212-2 in the formalin test is mediated partly by the activity of local GABAA receptors in the NC.


Assuntos
Benzoxazinas/farmacologia , Bicuculina/farmacologia , Agonistas de Receptores de GABA-A/farmacologia , Morfolinas/farmacologia , Muscimol/farmacologia , Naftalenos/farmacologia , Animais , Bicuculina/administração & dosagem , Canabinoides/farmacologia , Antagonistas de Receptores de GABA-A/farmacologia , Masculino , Nociceptividade/efeitos dos fármacos , Dor/tratamento farmacológico , Medição da Dor , Ratos , Ratos Wistar , Receptores de GABA-A/efeitos dos fármacos , Ácido gama-Aminobutírico/metabolismo
16.
Nat Neurosci ; 24(5): 658-666, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33737752

RESUMO

Cannabinoids reduce tremor associated with motor disorders induced by injuries and neurodegenerative disease. Here we show that this effect is mediated by cannabinoid receptors on astrocytes in the ventral horn of the spinal cord, where alternating limb movements are initiated. We first demonstrate that tremor is reduced in a mouse model of essential tremor after intrathecal injection of the cannabinoid analog WIN55,212-2. We investigate the underlying mechanism using electrophysiological recordings in spinal cord slices and show that endocannabinoids released from depolarized interneurons activate astrocytic cannabinoid receptors, causing an increase in intracellular Ca2+, subsequent release of purines and inhibition of excitatory neurotransmission. Finally, we show that the anti-tremor action of WIN55,212-2 in the spinal cords of mice is suppressed after knocking out CB1 receptors in astrocytes. Our data suggest that cannabinoids reduce tremor via their action on spinal astrocytes.


Assuntos
Astrócitos/metabolismo , Tremor Essencial/metabolismo , Interneurônios/metabolismo , Receptores de Canabinoides/metabolismo , Medula Espinal/metabolismo , Animais , Astrócitos/efeitos dos fármacos , Benzoxazinas/farmacologia , Agonistas de Receptores de Canabinoides/farmacologia , Modelos Animais de Doenças , Interneurônios/efeitos dos fármacos , Camundongos , Morfolinas/farmacologia , Naftalenos/farmacologia , Medula Espinal/efeitos dos fármacos , Transmissão Sináptica/efeitos dos fármacos , Transmissão Sináptica/fisiologia
17.
Science ; 371(6535)2021 03 19.
Artigo em Inglês | MEDLINE | ID: mdl-33542150

RESUMO

HIV-1 has high mutation rates and exists as mutant swarms within the host. Rapid evolution of HIV-1 allows the virus to outpace the host immune system, leading to viral persistence. Approaches to targeting immutable components are needed to clear HIV-1 infection. Here, we report that the caspase recruitment domain-containing protein 8 (CARD8) inflammasome senses HIV-1 protease activity. HIV-1 can evade CARD8 sensing because its protease remains inactive in infected cells before viral budding. Premature intracellular activation of the viral protease triggered CARD8 inflammasome-mediated pyroptosis of HIV-1-infected cells. This strategy led to the clearance of latent HIV-1 in patient CD4+ T cells after viral reactivation. Thus, our study identifies CARD8 as an inflammasome sensor of HIV-1, which holds promise as a strategy for the clearance of persistent HIV-1 infection.


Assuntos
Proteínas Adaptadoras de Sinalização CARD/metabolismo , Infecções por HIV/virologia , Protease de HIV/metabolismo , HIV-1/fisiologia , Inflamassomos/metabolismo , Proteínas de Neoplasias/metabolismo , Piroptose , Alcinos/farmacologia , Fármacos Anti-HIV/farmacologia , Benzoxazinas/farmacologia , Proteínas Adaptadoras de Sinalização CARD/química , Linfócitos T CD4-Positivos/fisiologia , Linfócitos T CD4-Positivos/virologia , Caspase 1/metabolismo , Ciclopropanos/farmacologia , Ativação Enzimática , Infecções por HIV/tratamento farmacológico , HIV-1/efeitos dos fármacos , Humanos , Macrófagos/fisiologia , Macrófagos/virologia , Proteínas de Neoplasias/química , Inibidores da Transcriptase Reversa/farmacologia , Rilpivirina/farmacologia , Células THP-1 , Latência Viral
18.
Arch Pharm (Weinheim) ; 354(2): e2000199, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33617016

RESUMO

Seventeen 1,4-benzoxazin-2-ones bearing the enaminone moiety and three of their analogs were tested for the antibacterial activity against Mycobacterium tuberculosis (H37Rv). Minimal bactericidal concentrations (MBCs) were determined after 41 days of incubation by BACTEC. 1,4-Benzoxazin-2-ones bearing the unsubstituted benzo moiety showed the most promising activities (MBC = 5.00 µg/ml). For most active compounds, antibacterial activities were determined daily during the 41 days. The most promising compound showed a bacteriostatic effect at a concentration of 0.31 µg/ml on Day 4 of incubation, 0.62 µg/ml on Day 6, 2.50 µg/ml on Day 9, and 5.00 µg/ml on Day 41. All studied compounds, along with some of their reported analogs, were docked to 35 proteins of M. tuberculosis to find their potent targets in these organisms. As a result of reverse docking, aspartate 1-decarboxylase, panD, was selected as the most appropriate target. Docking of the most active compounds to mutant panD from pyrazinamide-resistant strains of M. tuberculosis implies that they would not be active against these strains. Considering that most of pyrazinamide clinical resistance cases are due to loss-of-function mutations in pyrazinamidase, pncA, compounds from this study could be useful drugs for the treatment of some cases of pyrazinamide-resistant tuberculosis.


Assuntos
Antibacterianos/farmacologia , Benzoxazinas/farmacologia , Simulação de Acoplamento Molecular , Mycobacterium tuberculosis/efeitos dos fármacos , Antibacterianos/síntese química , Antibacterianos/química , Benzoxazinas/síntese química , Benzoxazinas/química , Relação Dose-Resposta a Droga , Humanos , Testes de Sensibilidade Microbiana , Estrutura Molecular
19.
Int J Biol Macromol ; 170: 664-673, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33387546

RESUMO

A new class of bio based polymer blends have been prepared from a modified chitosan based benzoxazine precursor (E-ch) and amino cellulose (AC). AC was derived from cellulose with excellent film-forming, biocompatibility and biodegradability property. E-ch was synthesized from eugenol, modified chitosan and paraformaldehyde. The chemical structure was confirmed by FT-IR and 1H NMR analyses. Bio films were prepared by mixing E-ch and AC with diluted acetic acid, in different ratios. These films were further cross-linked by applying heat, via ring-opening polymerization of benzoxazine without any curing agent. FT-IR and DSC were used to study the effects of AC on E-ch to form cross-linked network polymer films [poly(E-ch)/AC]. Hydrogen bonding interactions were found to exist between poly(E-ch) and AC. These kinds of interactions considerably improve the mechanical and thermal properties and char yield of the polymer films. Additionally, these biofilms; poly(E-ch) and poly(E-ch)/AC have been examined for bio-activity with S. aureus. It is confirmed that these bio-films are effective in inhibiting bio-film related infection. In a similar way, both the bio-films act against C. albicans and thus avoid the formation of mycological infection. These results expose that poly(E-ch) and AC bio-films are capable to act as anti-microbial and anti-fungal agents.


Assuntos
Antibacterianos/química , Antifúngicos/química , Benzoxazinas/química , Celulose/química , Polímeros/química , Antibacterianos/farmacologia , Antifúngicos/farmacologia , Benzoxazinas/farmacologia , Biofilmes/efeitos dos fármacos , Candida albicans/efeitos dos fármacos , Quitosana/química , Eugenol/química , Formaldeído/química , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Staphylococcus aureus/efeitos dos fármacos
20.
Neuropharmacology ; 182: 108374, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33115642

RESUMO

Synthetic cannabinoids were introduced into recreational drug culture in 2008 and quickly became one of the most commonly abused drugs in the United States. The neurobiological consequences resulting from synthetic cannabinoid repeated exposure remain poorly understood. It is possible that a blunted dopamine (DA) response may lead drug users to consume larger quantities to compensate for this form of neurochemical tolerance. Because the endogenous cannabinoid and opioid systems exhibit considerable cross-talk and cross-tolerance frequently develops following repeated exposure to either opioids or cannabinoids, there is interest in investigating whether a history of synthetic cannabinoid exposure influences the ability of heroin to increase DA release. To test the effects of chronic cannabinoid exposure on cannabinoid- and heroin-evoked DA release, male adult rats were treated with either vehicle or a synthetic cannabinoid (WIN55-212-2; WIN) using an intravenous (IV) dose escalation regimen (0.2-0.8 mg/kg IV over 9 treatments). As predicted, WIN-treated rats showed a rightward shift in the dose-response relationship across all behavioral/physiological measures when compared to vehicle-treated controls. Then, using fast-scan cyclic voltammetry to measure changes in the frequency of transient DA events in the nucleus accumbens shell of awake and freely-moving rats, it was observed that the DA releasing effects of both WIN and heroin were significantly reduced in male rats with a pharmacological history of cannabinoid exposure. These results demonstrate that repeated exposure to the synthetic cannabinoid WIN can produce tolerance to its DA releasing effects and cross-tolerance to the DA releasing effects of heroin.


Assuntos
Analgésicos Opioides/farmacologia , Benzoxazinas/farmacologia , Canabinoides/administração & dosagem , Dopamina/metabolismo , Tolerância a Medicamentos/fisiologia , Heroína/farmacologia , Morfolinas/farmacologia , Naftalenos/farmacologia , Fatores Etários , Analgésicos , Animais , Relação Dose-Resposta a Droga , Esquema de Medicação , Masculino , Medição da Dor/efeitos dos fármacos , Medição da Dor/métodos , Ratos , Ratos Long-Evans
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...