Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 52
Filtrar
1.
ACS Chem Neurosci ; 13(6): 721-732, 2022 03 16.
Artigo em Inglês | MEDLINE | ID: mdl-35226456

RESUMO

Oxidative stress and mitochondrial dysfunction are among the mechanisms expected to explain the pathogenesis of Huntington's disease. Erythropoietin (EPO) and the Bacillus Calmette-Guérin (BCG) vaccine have neuroprotective effects against neurodegenerative diseases; however, the full mechanisms of their action are currently unclear. Here, for the first time, we investigated the neuroprotective effect of BCG vaccination in Huntington-like disease induced by 3-nitropropionic acid (3-NP) and its combination with EPO. Male Wistar rats were randomized into five groups: saline-treated control; 3-NP group (20 mg/kg/day, i.p.) for 7 days; EPO-treated group (5000 IU/kg/day, i.p.) for 14 days after 3-NP administration; live BCG vaccine prophylactic group (5000 cfu/g, i.p.) 10 days prior to 3-NP administration; and live BCG vaccine (5000 cfu/g, i.p.) 10 days before 3-NP administration, followed by EPO treatment (5000 IU/kg/day, i.p.) for 14 days. In a histopathological examination, striatum neurodegeneration was evidenced in the 3-NP injected rats. Administration of 3-NP elevated the levels of p-PI3K, p-Akt, p-mTOR, p-P70S6K, BAX, malondialdehyde, nitric oxide, and cytochrome oxidase while reduced the levels of BCL-2, superoxide dismutase, reduced glutathione, and the autophagy marker microtubule-associated protein light chain 3 in the striatum. EPO and BCG ameliorated the biochemical, histopathological, and behavioral derangements induced by 3-NP, with prominent neuroprotection observed in rats administered the BCG prophylactic combined with EPO treatment. These results highlight the role played by EPO and BCG in the management of 3-NP-induced Huntington-like disease by inhibiting the PI3K/Akt/mTOR/P70S6K pathway and enhancing the autophagy.


Assuntos
Eritropoetina , Doença de Huntington , Fármacos Neuroprotetores , Animais , Autofagia , Vacina BCG , Eritropoetina/uso terapêutico , Doença de Huntington/induzido quimicamente , Doença de Huntington/tratamento farmacológico , Doença de Huntington/prevenção & controle , Masculino , Fármacos Neuroprotetores/uso terapêutico , Nitrocompostos/efeitos adversos , Fosfatidilinositol 3-Quinases , Propionatos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ratos , Ratos Wistar , Proteínas Quinases S6 Ribossômicas 70-kDa/uso terapêutico , Serina-Treonina Quinases TOR , Vacinação
2.
Sci Rep ; 11(1): 19998, 2021 10 07.
Artigo em Inglês | MEDLINE | ID: mdl-34620963

RESUMO

Understanding the effects of metabolism on the rational design of novel and more effective drugs is still a considerable challenge. To the best of our knowledge, there are no entirely computational strategies that make it possible to predict these effects. From this perspective, the development of such methodologies could contribute to significantly reduce the side effects of medicines, leading to the emergence of more effective and safer drugs. Thereby, in this study, our strategy is based on simulating the electron ionization mass spectrometry (EI-MS) fragmentation of the drug molecules and combined with molecular docking and ADMET models in two different situations. In the first model, the drug is docked without considering the possible metabolic effects. In the second model, each of the intermediates from the EI-MS results is docked, and metabolism occurs before the drug accesses the biological target. As a proof of concept, in this work, we investigate the main antiviral drugs used in clinical research to treat COVID-19. As a result, our strategy made it possible to assess the biological activity and toxicity of all potential by-products. We believed that our findings provide new chemical insights that can benefit the rational development of novel drugs in the future.


Assuntos
Antivirais/metabolismo , Tratamento Farmacológico da COVID-19 , Descoberta de Drogas , SARS-CoV-2/efeitos dos fármacos , Adenina/efeitos adversos , Adenina/análogos & derivados , Adenina/metabolismo , Adenina/farmacologia , Adenosina/efeitos adversos , Adenosina/análogos & derivados , Adenosina/metabolismo , Adenosina/farmacologia , Monofosfato de Adenosina/efeitos adversos , Monofosfato de Adenosina/análogos & derivados , Monofosfato de Adenosina/metabolismo , Monofosfato de Adenosina/farmacologia , Alanina/efeitos adversos , Alanina/análogos & derivados , Alanina/metabolismo , Alanina/farmacologia , Amidas/efeitos adversos , Amidas/metabolismo , Amidas/farmacologia , Antivirais/efeitos adversos , Antivirais/farmacologia , COVID-19/metabolismo , Cloroquina/efeitos adversos , Cloroquina/análogos & derivados , Cloroquina/metabolismo , Cloroquina/farmacologia , Desenho de Fármacos , Humanos , Redes e Vias Metabólicas , Simulação de Acoplamento Molecular , Nitrocompostos/efeitos adversos , Nitrocompostos/metabolismo , Nitrocompostos/farmacologia , Pirazinas/efeitos adversos , Pirazinas/metabolismo , Pirazinas/farmacologia , Pirrolidinas/efeitos adversos , Pirrolidinas/metabolismo , Pirrolidinas/farmacologia , Ribavirina/efeitos adversos , Ribavirina/metabolismo , Ribavirina/farmacologia , SARS-CoV-2/metabolismo , Tiazóis/efeitos adversos , Tiazóis/metabolismo , Tiazóis/farmacologia
3.
J Pharmacol Sci ; 147(4): 367-375, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34663519

RESUMO

Huntington's disease (HD) is an inherited neurodegenerative disorder caused by CAG repeat expansion in the huntingtin (HTT) gene. Here, we examined the effects of antioxidants on 3-nitropropionic acid (3-NP; a mitochondrial complex II inhibitor)-induced mitochondrial dysfunction and cell death in STHdhQ111 striatal cells carrying homozygous mutant HTT with extended CAG repeats compared with those in STHdhQ7 striatal cells. 3-NP reduced cell viability and increased cell death both in STHdhQ111 and STHdhQ7, and the cytotoxicity was markedly attenuated by antioxidants (N-acetyl-l-cysteine and edaravone). Furthermore, 3-NP increased intracellular reactive oxygen species (ROS) production in both cell lines, and this increase was inhibited by antioxidants. Mitochondrial ROS was also increased by 3-NP in STHdhQ111 but not in STHdhQ7, and this increase was significantly inhibited by edaravone. Mitochondrial membrane potential (MMP) was lower in STHdhQ111 than that in STHdhQ7, and antioxidants prevented 3-NP-induced MMP decrease in STHdhQ111.3-NP enhanced oligomerization of dynamin-related protein 1 (Drp1), a protein that promotes mitochondrial fission in both cells, and both antioxidants prevented the increase in oligomerization. These results suggest that reduced mitochondrial complex II activity enhances cell death via intracellular ROS production and Drp1 oligomerization in striatal cells with mutant HTT and antioxidants may reduce striatal cell death.


Assuntos
Antioxidantes/farmacologia , Morte Celular/efeitos dos fármacos , Morte Celular/genética , Complexo II de Transporte de Elétrons/metabolismo , Proteína Huntingtina/genética , Doença de Huntington/genética , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Mutação/genética , Espécies Reativas de Oxigênio/metabolismo , Expansão das Repetições de Trinucleotídeos/genética , Animais , Edaravone/farmacologia , Complexo II de Transporte de Elétrons/antagonistas & inibidores , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Camundongos Transgênicos , Dinâmica Mitocondrial/efeitos dos fármacos , Nitrocompostos/efeitos adversos , Nitrocompostos/antagonistas & inibidores , Propionatos/efeitos adversos , Propionatos/antagonistas & inibidores
4.
Expert Opin Drug Metab Toxicol ; 17(4): 355-357, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33432831

RESUMO

Introduction: The CD47 and SIRPα checkpoint pathway has garnered much interest within the anti-cancer research community, with multiple experimental checkpoint inhibitors targeting CD47 and SIRPα in development. The use of such checkpoint inhibitors may however be limited by hematologic toxicity.Areas covered: We report on RRx-001, the first known small molecule downregulator of CD47 and SIRPα, which has shown a lack of hematologic toxicity in clinical trials.Expert opinion: RRx-001 is the first reported small molecule downregulator of CD47 and SIRPα and lacks any notable hematologic or systemic toxicity as demonstrated in clinical trials to date. Small molecule RRx-001 could be used in combination with or in place of CD47 targeting antibodies for anti-cancer treatment.


Assuntos
Antineoplásicos/efeitos adversos , Azetidinas/efeitos adversos , Nitrocompostos/efeitos adversos , Anemia/epidemiologia , Anemia/etiologia , Antígenos de Diferenciação/metabolismo , Antineoplásicos/administração & dosagem , Antineoplásicos/farmacologia , Azetidinas/administração & dosagem , Azetidinas/farmacologia , Antígeno CD47/metabolismo , Humanos , Nitrocompostos/administração & dosagem , Nitrocompostos/farmacologia , Receptores Imunológicos/metabolismo , Trombocitopenia/epidemiologia , Trombocitopenia/etiologia
5.
Expert Opin Investig Drugs ; 30(2): 177-183, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33306414

RESUMO

Background: In a Phase II study RRx-001 was combined with Etoposide platinum (EP) in previously platinum treated SCLC. We correlated expression of the M2 marker, CD206, on HLA-DRlow/- monocytes, a phenotype that correlates with a poor prognosis, with response to RRx-001. Research design and methods: Patients received 4 mg RRx-001 once weekly until progression followed by the start of EP (etoposide 100 mg/m2 IV on days 1-3 of a 21-day cycle and either cisplatin 80 mg/m2 IV on day 1 or carboplatin AUC 5-6 IV on day 1). Treatment continued until progression or intolerable toxicity. Peripheral blood was collected in Cell Preparation Tubes with sodium citrate from 14 patients for exploratory studies during screening and after therapy on Days 1, 8, and 15. Peripheral blood mononuclear cells (PBMCs) were isolated from blood by centrifugation and multiparameter flow cytometric analysis was performed. Results: CD206 expression on HLA-DRlow/- monocytes was associated with response to chemotherapy and overall survival. Conclusion: During treatment with RRx-001, reduced expression of the protumorigenic M2 marker CD206 on peripheral monocytes positively correlated with increased response and survival.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Azetidinas/uso terapêutico , Carboplatina/uso terapêutico , Cisplatino/uso terapêutico , Etoposídeo/uso terapêutico , Neoplasias Pulmonares/tratamento farmacológico , Nitrocompostos/uso terapêutico , Carcinoma de Pequenas Células do Pulmão/tratamento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Azetidinas/efeitos adversos , Carboplatina/efeitos adversos , Cisplatino/efeitos adversos , Progressão da Doença , Etoposídeo/efeitos adversos , Antígenos HLA-DR/sangue , Humanos , Neoplasias Pulmonares/sangue , Neoplasias Pulmonares/mortalidade , Neoplasias Pulmonares/patologia , Glicoproteínas de Membrana/sangue , Nitrocompostos/efeitos adversos , Receptores Imunológicos/sangue , Carcinoma de Pequenas Células do Pulmão/sangue , Carcinoma de Pequenas Células do Pulmão/mortalidade , Carcinoma de Pequenas Células do Pulmão/patologia , Fatores de Tempo , Resultado do Tratamento , Macrófagos Associados a Tumor/efeitos dos fármacos , Macrófagos Associados a Tumor/metabolismo
6.
Apoptosis ; 26(1-2): 52-70, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33226552

RESUMO

Striatal neurons depends on an afferent supply of brain-derived neurotrophic factor-(BDNF) that explicitly interacts with tropomyosin receptor kinase B (TrkB) receptor and performs sundry functions including synaptic plasticity, neuronal differentiation and growth. Therefore, we aimed to scrutinize an active molecule that functions identical to BDNF in activating TrkB receptor and it's downstream targets for restoring neuronal survival in Huntington disease (HD). Data from in vitro Neuro-2a cell line showed that treatment with 7,8-dihydroxyflavone (7,8-DHF), improved 3-nitropropionic acid (3-NP) induced neuronal death by stabilizing the loss of mitochondrial membrane potential and transiently increased the activity of cAMP-response element-binding protein (CREB) and BDNF via TrkB receptor activation. Consistent with in vitro findings, our in vivo results stated that treatment with 7,8-DHF at a dose of 10 mg/kg body weight ameliorated various behavior alterations caused by 3-NP intoxication. Further histopathological and electron microscopy evidences from striatal region of 3-NP mice brain treated with 7,8-DHF showed more improved neurons with intact mitochondria and less autophagic vacuoles. Protein expression analysis of both in vitro and in vivo study showed that 7,8-DHF promotes neuronal survival through upregulation and phosphorylation of phosphatidylinositol 3-kinase (PI3K) and Akt at serine-473/threonine-308). Akt phosphorylation additionally phosphorylates Bad at serine-136 and inhibits its translocation to mitochondria thereby promoting mitochondrial biogenesis, enhanced ATP production and inhibit apoptosis mediated neuronal death. These aforementioned findings help in strengthening our hypothesis and has come up with a novel neuroprotective mechanism of 7,8-DHF against 3-NP induced neuronal death.


Assuntos
Fator Neurotrófico Derivado do Encéfalo/metabolismo , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Flavonas/administração & dosagem , Doença de Huntington/fisiopatologia , Glicoproteínas de Membrana/agonistas , Neurônios/citologia , Fosfatidilinositol 3-Quinase/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Animais , Apoptose/efeitos dos fármacos , Fator Neurotrófico Derivado do Encéfalo/genética , Morte Celular/efeitos dos fármacos , Sobrevivência Celular , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/genética , Humanos , Doença de Huntington/tratamento farmacológico , Doença de Huntington/genética , Doença de Huntington/metabolismo , Masculino , Glicoproteínas de Membrana/genética , Glicoproteínas de Membrana/metabolismo , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos C57BL , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/genética , Mitocôndrias/metabolismo , Neurônios/metabolismo , Fármacos Neuroprotetores/administração & dosagem , Nitrocompostos/efeitos adversos , Fosfatidilinositol 3-Quinase/genética , Propionatos/efeitos adversos , Proteínas Tirosina Quinases/genética , Proteínas Tirosina Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/genética , Transdução de Sinais
7.
Int J Mol Sci ; 21(7)2020 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-32260390

RESUMO

The rhizome of Anemarrhena asphodeloides Bunge, used in Traditional Chinese Medicine as a brain function-improving herb, is a promising source of neuroprotective substances. The aim of this study was to evaluate the protective action of xanthones from A. asphodeloides rhizomes on the PC12 cell line exposed to the neurotoxic agent-3-nitropropionic acid (3-NP). The xanthone-enriched fraction of the ethanolic extract of A. asphodeloides (abbreviated from now on as XF, for the Xanthone Fraction), rich in polyphenolic xanthone glycosides, in concentrations from 5 to 100 µg/mL, and 3-NP in concentrations from 2.5 to 15 mM, were examined. After 8, 16, 24, 48, and 72 h of exposure of cells to various combinations of 3-NP and XF, the MTT viability assay was performed and morphological changes were estimated by confocal fluorescence microscopy. The obtained results showed a significant increase in the number of cells surviving after treatment with XF with exposure to neurotoxic 3-NP and decreased morphological changes in PC12 cells in a dose and time dependent manner. The most effective protective action was observed when PC12 cells were pre-incubated with the XF. This effect may contribute to the traditional indications of this herb for neurological and cognitive complaints. However, a significant cytotoxicity observed at higher XF concentrations (over 10 µg/mL) and longer incubation time (48 h) requires caution in future research and thorough investigation into potential adverse effects.


Assuntos
Anemarrhena/química , Fármacos Neuroprotetores/farmacologia , Nitrocompostos/efeitos adversos , Células PC12/citologia , Propionatos/efeitos adversos , Xantonas/farmacologia , Animais , Apoptose/efeitos dos fármacos , Relação Dose-Resposta a Droga , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/farmacologia , Estrutura Molecular , Fármacos Neuroprotetores/química , Células PC12/efeitos dos fármacos , Ratos , Rizoma/química , Fatores de Tempo , Xantonas/química
8.
Biochem Soc Trans ; 48(2): 709-717, 2020 04 29.
Artigo em Inglês | MEDLINE | ID: mdl-32129826

RESUMO

Mechanisms responsible for neuronal vulnerability in the brain remain unclear. Striatal neurons are preferentially damaged by 3-nitropropionic acid (3-NP), a mitochondrial complex-II inhibitor, causing striatal damage reminiscent of Huntington's disease (HD), but the mechanisms of the selectivity are not as well understood. We have discovered that Rhes, a protein enriched in the striatum, removes mitochondria via the mitophagy process. The process becomes intensified in the presence of 3-NP, thereby eliminating most of the mitochondria from the striatum. We put forward the hypothesis that Rhes acts as a 'mitophagy ligand' in the brain and promotes mitophagy via NIX, a mitophagy receptor. Since Rhes interacts and promotes toxicity in association with mutant huntingtin (mHTT), the genetic cause of HD, it is tempting to speculate on whether the exaggerated mitophagy may be a contributing factor to the striatal lesion found in HD. Thus, Rhes-mediated exaggerated mitophagy may act as a weapon of striatal destruction in the brain.


Assuntos
Encéfalo/efeitos dos fármacos , Encéfalo/patologia , Doença de Huntington/tratamento farmacológico , Mitofagia , Nitrocompostos/efeitos adversos , Propionatos/efeitos adversos , Animais , Corpo Estriado/metabolismo , Desenvolvimento de Medicamentos , Hipocampo/metabolismo , Humanos , Proteína Huntingtina/genética , Lisossomos/metabolismo , Proteínas de Membrana/metabolismo , Mitocôndrias/metabolismo , Neurônios/metabolismo , Domínios Proteicos , Proteínas Proto-Oncogênicas/metabolismo
9.
Sci Total Environ ; 678: 611-617, 2019 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-31078851

RESUMO

Extensive epidemiological studies have revealed that nearly 25% of the premature mortality from lung cancer is attributed to regional haze caused by a high level of fine particulate matter (PM2.5). The nitro-PAHs (NPAHs), with a lower volatility, are more likely to be absorbed with PM2.5 and to pose a threat to health, whereas there is insufficient information about carcinogenesis caused by NPAHs. Our study evaluated the carcinogenic effect of typical NPAHs on lung cancer cell adhesion and metastasis and revealed the possibly involved mechanism through in vitro experiments. For the specific mechanism, typical NPAHs could directly induce the inactivation of serine/threonine kinase (MST1/2) and large tumor suppressor (LATS1/2) and result in the nuclear translocation of Yes-associated protein (YAP). The nuclear YAP would then combine with TEA domain transcription factor (TEAD) and profoundly influence the transcription of migration and adhesion genes related to lung cancer metastasis. These findings remind us of the possible carcinogenicity of NPAHs absorbed with PM2.5 and provide a reference for the prevention and mitigation of tumorigenesis in a heavily polluted environment.


Assuntos
Transformação Celular Neoplásica , Transição Epitelial-Mesenquimal , Nitrocompostos/efeitos adversos , Material Particulado/efeitos adversos , Hidrocarbonetos Policíclicos Aromáticos/efeitos adversos , Transdução de Sinais/efeitos dos fármacos , Células A549 , Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Poluentes Atmosféricos/efeitos adversos , Adesão Celular , Via de Sinalização Hippo , Humanos , Neoplasias Pulmonares/patologia , Metástase Neoplásica/fisiopatologia , Fosfoproteínas/genética , Fosfoproteínas/metabolismo , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , Fatores de Transcrição , Proteínas de Sinalização YAP
10.
J Exp Biol ; 221(Pt 7)2018 04 11.
Artigo em Inglês | MEDLINE | ID: mdl-29643175

RESUMO

Neonicotinoids are the most widespread insecticides in agriculture, preferred for their low toxicity to mammals and their systemic nature. Nevertheless, there have been increasing concerns regarding their impact on non-target organisms. Glyphosate is also widely used in crops and, therefore, traces of this pesticide are likely to be found together with neonicotinoids. Although glyphosate is considered a herbicide, adverse effects have been found on animal species, including honey bees. Apis mellifera is one of the most important pollinators in agroecosystems and is exposed to both these pesticides. Traces can be found in nectar and pollen of flowers that honey bees visit, but also in honey stores inside the hive. Young workers, which perform in-hive tasks that are crucial for colony maintenance, are potentially exposed to both these contaminated resources. These workers present high plasticity and are susceptible to stimuli that can modulate their behaviour and impact on colony state. Therefore, by performing standardised assays to study sublethal effects of these pesticides, these bees can be used as bioindicators. We studied the effect of chronic joint exposure to field-realistic concentrations of the neonicotinoid imidacloprid and glyphosate on gustatory perception and olfactory learning. Both pesticides reduced sucrose responsiveness and had a negative effect on olfactory learning. Glyphosate also reduced food uptake during rearing. The results indicate differential susceptibility according to honey bee age. The two agrochemicals had adverse effects on different aspects of honey bee appetitive behaviour, which could have repercussions for food distribution, propagation of olfactory information and task coordination within the nest.


Assuntos
Abelhas/efeitos dos fármacos , Glicina/análogos & derivados , Herbicidas/efeitos adversos , Inseticidas/efeitos adversos , Aprendizagem/efeitos dos fármacos , Neonicotinoides/efeitos adversos , Nitrocompostos/efeitos adversos , Percepção Gustatória/efeitos dos fármacos , Animais , Aprendizagem por Associação/efeitos dos fármacos , Glicina/efeitos adversos , Olfato/efeitos dos fármacos , Glifosato
11.
J Toxicol Environ Health A ; 81(8): 229-239, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29437547

RESUMO

Imidacloprid (IMD) is a neonicotinoid insecticide widely used in crops, pets, and on farm animals for pest control. Several studies were conducted examining the adverse effects of IMD on animals often exhibiting hepatic damage. The aim of this study was to determine the effects of IMD on bioenergetics of mitochondria isolated from rat liver. Imidacloprid (50-200 µM) produced a concentration-dependent decrease in oxygen consumption and ATP production without markedly affecting mitochondrial membrane potential (MMP). Oxygen consumption experiments showed that IMD did not significantly affect the respiratory chain, and this was similar to findings with oligomycin and carboxyatractyloside, suggesting a direct action on FoF1-ATP synthase and/or the adenine nucleotide translocator (ANT). Imidacloprid inhibited FoF1-ATP synthase activity only in disrupted mitochondria and induced a partial inhibition of ADP-stimulated depolarization of the MMP. Our results indicate that IMD interacts specifically with FoF1-ATP synthase resulting in functional inhibition of the enzyme with consequent impairment of mitochondrial bioenergetics. These effects of IMD on mitochondrial bioenergetics may be related to adverse effects of this insecticide on the liver.


Assuntos
Metabolismo Energético/efeitos dos fármacos , Inseticidas/efeitos adversos , Fígado/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Neonicotinoides/efeitos adversos , Nitrocompostos/efeitos adversos , ATPases Translocadoras de Prótons/metabolismo , Animais , Fígado/enzimologia , Masculino , Mitocôndrias/enzimologia , Ratos , Ratos Wistar
12.
J Insect Physiol ; 104: 33-39, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29133226

RESUMO

For bumble bees (genus Bombus), the capacity for non-flight thermogenesis is essential for two fundamental processes undertaken by adult workers, namely recovery from torpor after chilling and brood incubation. Farmland bees can be widely exposed to dietary residues of neurotoxic neonicotinoid insecticides that appear in the nectar and pollen of treated bee-attractive crops, which may harm them. An earlier study shows that dietary neonicotinoids cause complex alterations to thermoregulation in honey bees, but their effect on the thermogenic capabilities of individual bumble bees has been untested previously. We therefore conducted laboratory trials involving separate dietary exposures of bumble bees to two neonicotinoids, imidacloprid and thiamethoxam, and we measured their effects on the thoracic temperatures of bees during recovery from chilling. Specifically, we used thermal imaging to measure the rates of rewarming by individual bees after chill-induced torpor and to quantify their equilibrated thoracic temperatures post-recovery. We found that both toxicants caused dose-dependent decreases in the rates of rewarming and in the equilibrated thoracic temperatures. As previously found in honey bees, the dose-response relationship for imidacloprid exhibited a biphasic hormesis with low-dose stimulation and high-dose inhibition, for which we propose a mechanism. Our present study is among the first to detect ecologically relevant effects on bees in neonicotinoid exposures involving dietary concentrations below 5 ppb. If the effects on thoracic temperatures that we observed over a short period were sustained, they could have ecologically significant impacts on farmland bumble bees.


Assuntos
Abelhas/fisiologia , Inseticidas/efeitos adversos , Neonicotinoides/efeitos adversos , Termogênese/efeitos dos fármacos , Animais , Abelhas/efeitos dos fármacos , Dieta , Relação Dose-Resposta a Droga , Nitrocompostos/efeitos adversos , Oxazinas/efeitos adversos , Distribuição Aleatória , Tiametoxam , Tiazóis/efeitos adversos
13.
Proc Biol Sci ; 284(1869)2017 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-29263280

RESUMO

The honey bee is a major pollinator whose health is of global concern. Declines in bee health are related to multiple factors, including resource quality and pesticide contamination. Intensive agricultural areas with crop monocultures potentially reduce the quality and quantity of available nutrients and expose bee foragers to pesticides. However, there is, to date, no evidence for synergistic effects between pesticides and nutritional stress in animals. The neonicotinoids clothianidin (CLO) and thiamethoxam (TMX) are common systemic pesticides that are used worldwide and found in nectar and pollen. We therefore tested if nutritional stress (limited access to nectar and access to nectar with low-sugar concentrations) and sublethal, field-realistic acute exposures to two neonicotinoids (CLO and TMX at 1/5 and 1/25 of LD50) could alter bee survival, food consumption and haemolymph sugar levels. Bee survival was synergistically reduced by the combination of poor nutrition and pesticide exposure (-50%). Nutritional and pesticide stressors reduced also food consumption (-48%) and haemolymph levels of glucose (-60%) and trehalose (-27%). Our results provide the first demonstration that field-realistic nutritional stress and pesticide exposure can synergistically interact and cause significant harm to animal survival. These findings have implications for current pesticide risk assessment and pollinator protection.


Assuntos
Abelhas/fisiologia , Guanidinas/efeitos adversos , Inseticidas/efeitos adversos , Neonicotinoides/efeitos adversos , Nitrocompostos/efeitos adversos , Oxazinas/efeitos adversos , Tiazóis/efeitos adversos , Fenômenos Fisiológicos da Nutrição Animal/efeitos dos fármacos , Animais , Abelhas/efeitos dos fármacos , Privação de Alimentos , Longevidade/efeitos dos fármacos , Tiametoxam
14.
J Agric Food Chem ; 65(31): 6572-6581, 2017 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-28704996

RESUMO

Imidacloprid, a neonicotinoid insecticide, was previously reported to enhance adipogenesis and resulted in insulin resistance in cell culture models. It was also reported to promote high fat diet-induced obesity and insulin resistance in male C57BL/6J mice. Thus, the goal of the present study was to determine the effects of imidacloprid and dietary fat interaction on the development of adiposity and insulin resistance in female C57BL/6J mice. Mice were fed with a low (4% w/w) or high fat (20% w/w) diet containing imidacloprid (0.06, 0.6, or 6 mg/kg bw/day) for 12 weeks. Mice fed with imidacloprid (0.6 mg/kg bw/day) significantly enhanced high fat diet-induced weight gain and adiposity. Treatment with imidacloprid significantly increased serum insulin levels with high fat diet without effects on other markers of glucose homeostasis. AMPKα activation was significantly inhibited by 0.6 and 6 mg imidacloprid/kg bw/day in white adipose tissue. Moreover, AMPKα activation with 5-aminoimidazole-4-carboxamide ribonucleotide abolished the effects of imidacloprid (10 µM) on enhanced adipogenesis in 3T3-L1 adipocytes. N-Acetyl cysteine also partially reversed the effects of imidacloprid on reduced phosphorylation of protein kinase B (AKT) in C2C12 myotubes. These results indicate that imidacloprid may potentiate high fat diet-induced adiposity in female C57BL/6J mice and enhance adipogenesis in 3T3-L1 adipocytes via the AMPKα-mediated pathway. Imidacloprid might also influence glucose homeostasis partially by inducing cellular oxidative stress in C2C12 myotubes.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Adipócitos/efeitos dos fármacos , Adipogenia/efeitos dos fármacos , Adiposidade/efeitos dos fármacos , Imidazóis/efeitos adversos , Inseticidas/efeitos adversos , Nitrocompostos/efeitos adversos , Obesidade/metabolismo , Proteínas Quinases Ativadas por AMP/genética , Adipócitos/citologia , Adipócitos/metabolismo , Animais , Dieta Hiperlipídica/efeitos adversos , Feminino , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Neonicotinoides , Obesidade/etiologia , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais/efeitos dos fármacos
15.
Biomed Pharmacother ; 91: 1022-1041, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28531918

RESUMO

Imidacloprid (IMI) is very harmful to human health and cause problems. Recently, plants have been considered as potential agents for protection against these disorders. Urtica urens L. (UU) is very useful for relieving rheumatic pains and there is no scientific evidence justifying its use, which lets us think of its direct effect on the bone. This study aimed to investigate the protective effect of UU against toxicity effects of IMI in female rat. Rats were divided into control group, 3 groups treated with IMI at 50, 200 or 300mg/kg/day and 3 groups co-treated with IMI (50, 200 or 300mg/kg/day)+100mg/kg/day of UU. We studied bone remodeling through histological, histomorphometry and biochemical analyses. In IMI- treated groups, we have noted, following histomorphomotric analysis, significant decreases in cortical, trabecular thicknesses and osteoid surfaces. Elsewhere, IMI intoxication significantly decreased serum vitamin D and hydroxyproline levels in the groups treated for 60days. IMI intoxication increased significantly calcium, phosphorus contents, MDA and AOPP levels and the rate of calcification. It decreased significantly GSH, GPx, SOD, CAT, 17b-Estradiol and vitamin E levels, induces a tendency of rarefaction and increases of intrabecular spaces. The co-treatment with UU improved all biochemical parameters (hydroxyproline, MDA, AOPP, GSH, GPx, SOD, CAT, 17b-Estradiol, vitamin D, vitamin E calcium, phosphorus). UU leads to a significant increase in cortical, trabecular thicknesses, osteoid surfaces, a decrease in the intrabecular spaces and the rarefaction of bone. In conclusion, IMI inhibits bone remodeling and enhances bone formation. A significant antioxidant activity was also observed in UU and a total of 6 compounds were identified. Co-administration of UU provided a significant protection which might be due to its antioxidant property.


Assuntos
Remodelação Óssea/efeitos dos fármacos , Etanol/química , Neonicotinoides/efeitos adversos , Nitrocompostos/efeitos adversos , Extratos Vegetais/farmacologia , Substâncias Protetoras/farmacologia , Urticaceae/química , Animais , Antioxidantes/metabolismo , Osso e Ossos/efeitos dos fármacos , Osso e Ossos/metabolismo , Cálcio/metabolismo , Estradiol/metabolismo , Feminino , Hidroxiprolina/sangue , Malondialdeído/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Fósforo/metabolismo , Ratos , Vitamina D/sangue , Vitamina E/sangue
16.
Expert Opin Investig Drugs ; 26(1): 109-119, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27935336

RESUMO

INTRODUCTION: According to Hanahan and Weinberg, cancer manifests as six essential physiologic hallmarks: (1) self-sufficiency in growth signals, (2) insensitivity to growth-inhibitory signals, (3) evasion of programmed cell death, (4) limitless replicative potential, (5) sustained angiogenesis, and (6) invasion and metastasis. As a facilitator of these traits as well as immunosuppression and chemoresistance, the presence of tumor-associated macrophages (TAMs) may serve as the seventh hallmark of cancer. Anticancer agents that successfully reprogram TAMs to target rather than support tumor cells may hold the key to better therapeutic outcomes. Areas covered: This article summarizes the characteristics of the macrophage-stimulating agent RRx-001, a molecular iconoclast, sourced from the aerospace industry, with a particular emphasis on the cell-to-cell transfer mechanism of action (RBCs to TAMs) underlying its antitumor activity as well as its chemo and radioprotective properties, consolidated from various preclinical and clinical studies. Expert opinion: RRx-001 is macrophage-stimulating agent with the potential to synergize with chemotherapy, radiotherapy and immunotherapy while simultaneously protecting normal tissues from their cytotoxic effects. Given the promising indications of activity in multiple tumor types and these normal tissue protective properties, RRx-001 may be used to treat a broad spectrum of malignancies, if it is approved in the future.


Assuntos
Azetidinas/uso terapêutico , Macrófagos/efeitos dos fármacos , Neoplasias/tratamento farmacológico , Nitrocompostos/uso terapêutico , Animais , Antineoplásicos/efeitos adversos , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Azetidinas/efeitos adversos , Azetidinas/farmacologia , Morte Celular/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos , Humanos , Macrófagos/metabolismo , Neoplasias/patologia , Nitrocompostos/efeitos adversos , Nitrocompostos/farmacologia
17.
Acta Pharm ; 66(3): 443-8, 2016 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-27383892

RESUMO

The study tested the hypothesis that cerebrolysin protects the brain from free radicals in rats treated with 3-nitropropionic acid (3-NPA). To address this hypothesis, the levels of dopamine (DA) and some oxidative stress biomarkers were measured after administration of 3-NPA. Young male Fischer rats were treated for three days with cerebrolysin, 3-NPA or both substances. Their brains were extracted, and DA, lipid peroxidation (LP), glutathione (GSH), calcium, and H2O2 were measured using validated methods. In the cortex, hemispheres and cerebellum/medulla oblongata of the group treated with cerebrolysin and 3-NPA, the levels of DA and LP decreased. In addition, calcium and H2O2 levels decreased in the hemispheres of the same group, while GSH increased in cortex. The increased dopamine metabolism due to the administration of cerebrolysin led to increased formation of radical species and oxidative stress, especially when free radicals were generated by 3-NPA.


Assuntos
Aminoácidos/uso terapêutico , Antioxidantes/uso terapêutico , Neurônios Dopaminérgicos/efeitos dos fármacos , Doenças Neurodegenerativas/prevenção & controle , Fármacos Neuroprotetores/uso terapêutico , Síndromes Neurotóxicas/prevenção & controle , Estresse Oxidativo/efeitos dos fármacos , Aminoácidos/efeitos adversos , Animais , Antioxidantes/efeitos adversos , Cálcio/metabolismo , Córtex Cerebelar/efeitos dos fármacos , Córtex Cerebelar/metabolismo , Cerebelo/efeitos dos fármacos , Cerebelo/metabolismo , Cérebro/efeitos dos fármacos , Cérebro/metabolismo , Convulsivantes/efeitos adversos , Dopamina/metabolismo , Neurônios Dopaminérgicos/metabolismo , Glutationa/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Masculino , Bulbo/efeitos dos fármacos , Bulbo/metabolismo , Doenças Neurodegenerativas/induzido quimicamente , Doenças Neurodegenerativas/metabolismo , Fármacos Neuroprotetores/efeitos adversos , Síndromes Neurotóxicas/metabolismo , Nitrocompostos/efeitos adversos , Propionatos/efeitos adversos , Ratos Endogâmicos F344
18.
Pestic Biochem Physiol ; 131: 9-17, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27265821

RESUMO

The imidacloprid is used worldwide as a pesticide and has been linked with endocrine disturbances and reduced pulmonary function. However, effects of imidacloprid alone or in combination with microbial molecules on lungs are not fully understood. Because the pulmonary effects of interactions of endotoxins with imidacloprid are unknown, we designed a study to investigate that in a mouse model. Mice (N=14) were given imidacloprid orally @ 1/20(th) of LD50 dissolved in corn oil for 30days. After the treatments, six animals from each group were challenged with E. coli lipopolysaccharide (LPS) @ 80µg/animal via intranasal route and remaining animals were challenged with normal saline solution @ 80µl/animal via same route. Imidacloprid in combination with LPS led to significant increase in total cell and neutrophil counts in BAL and peripheral blood. Semi-quantitative histopathology revealed lung injury in imidacloprid treatment group and injury was more marked in animal receiving both imidacloprid and LPS. There was no change (p<0.05) in the expression of TLR-4 and TNF-α both at mRNA and protein levels following exposure to imidacloprid alone or in combination with LPS. The data show that imidacloprid alone or in combination with LPS resulted changes in lung morphology without altering the expression of TLR-4 and TNF-α. Furthermore, pre-treatment with imidacloprid didn't affect response to LPS.


Assuntos
Imidazóis/efeitos adversos , Inseticidas/efeitos adversos , Pulmão/efeitos dos fármacos , Nitrocompostos/efeitos adversos , Receptor 4 Toll-Like/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Animais , Relação Dose-Resposta a Droga , Lipopolissacarídeos/farmacologia , Pulmão/metabolismo , Pulmão/patologia , Masculino , Camundongos , Neonicotinoides
19.
Med Tr Prom Ekol ; (3): 12-6, 2016.
Artigo em Russo | MEDLINE | ID: mdl-27265938

RESUMO

Imidacloprid is a relatively new insecticide in neonicotinoids chemical class with neuroactivity in insects, being one of the most widely used insecticides in the world. For biomonitoring in workers exposed to pesticides, the authors designed a method detecting low levels of Imidacloprid in urine of operators, based on tandem liquid mass-spectrometry with ionization source--electrostatic dispersion (positive ionization) in multi-reaction monitoring regime with subsidiary ion (mass/charge) 209 for quantitative assessment and ion 175.1 for confirmation onion ratio. The study incorporated diurnal urine, about 100 ml of average sample was frozen and kept at temperature -20C for analysis. Before extraction, the sample was unfrozen, an aliquot of 5 ml was selected, diluted with 5 ml of 0.1% formic acid. The substance was concentrated out of the urine samples via solid-phase extraction with application of cartridges based on octadecylsilane, eluition--1 ml of methanol. Lower limit of Imidacloprid detection in urine is 0.02 ng/ml, of the quantitative assessment--0.1 ng/ ml, linear range of concentrations measured 0.1-10 ng/ml. The method was tested for monitoring in workers exposed to Imidacloprid preparations in natural conditions of pesticides application in agriculture, with various processing technologies. Imidacloprid was identified in urine of two professional operators after work in seed treatment and the subsequent seeding at lower limit of detection (0.02 ng/ml) and 0.34 ng/ml.


Assuntos
Agricultura/métodos , Imidazóis , Nitrocompostos , Exposição Ocupacional , Segurança , Doenças dos Trabalhadores Agrícolas/etiologia , Doenças dos Trabalhadores Agrícolas/prevenção & controle , Monitoramento Ambiental/métodos , Humanos , Imidazóis/efeitos adversos , Imidazóis/urina , Neonicotinoides , Nitrocompostos/efeitos adversos , Nitrocompostos/urina , Exposição Ocupacional/análise , Exposição Ocupacional/prevenção & controle , Praguicidas/efeitos adversos , Praguicidas/urina , Reprodutibilidade dos Testes , Extração em Fase Sólida/métodos , Espectrometria de Massas em Tandem/métodos
20.
Nutr Neurosci ; 19(2): 70-8, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-25896328

RESUMO

OBJECTIVE: To isolate the neuroprotective component from Convolvulus pluricaulis Chois. (Convolvulaceae) which can be used as a lead molecule in the treatment of Huntington's disease (HD). METHODS: The methanolic extract of whole plant was fractionated into four fractions; chloroform, ethyl acetate, n-butanol, and aqueous fraction. The chloroform and ethyl acetate fractions were pooled on the basis of antioxidant activity and TLC profile and charged into silica gel column. Four subfractions were collected from column (FrA, FrB, FrC, and FrD) and further assessed for antioxidant potential by 2,2-diphenyl-1-picrylhydrazyl in vitro assay. 3-Nitropropionic acid (3-NP) was administered to Wister rats for induction of HD. Different fractions were administered for 14 days. Different behavioral alterations were assessed in between study period. Animals were euthanized immediately following the last behavioral session, and biochemical parameters were measured. RESULT AND DISCUSSION: Systemic administration of 3-NP showed marked motor deficits and oxidative damage in rats. Only FrB showed significant antioxidant activity and on further purification gave pure compound (scopoletin). Our study showed that FrB (20 mg/kg) pre-treatment significantly attenuated the loss in body weight, improved the locomotor activity, grip strength, and gait abnormalities. It also has attenuated the increased malondialdehyde and nitrite levels, and restored superoxide dismutase and reduced GSH enzyme activity in the striatum and cortex in 3-NP-treated groups. These results suggest that C. pluricaulis Chois. exhibits a neuroprotective effect by accelerating brain antioxidant defense mechanisms in 3-NP-treated rats.


Assuntos
Antioxidantes/farmacologia , Convolvulus/química , Doença de Huntington/tratamento farmacológico , Fármacos Neuroprotetores/farmacologia , Animais , Comportamento Animal , Peso Corporal , Corpo Estriado/efeitos dos fármacos , Corpo Estriado/metabolismo , Glutationa/metabolismo , Doença de Huntington/induzido quimicamente , Peroxidação de Lipídeos/efeitos dos fármacos , Masculino , Malondialdeído/metabolismo , Síndromes Neurotóxicas/tratamento farmacológico , Nitritos/metabolismo , Nitrocompostos/efeitos adversos , Propionatos/efeitos adversos , Ratos , Ratos Wistar , Superóxido Dismutase/metabolismo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA