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1.
Eur J Neurosci ; 2023 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-37539658

RESUMO

The dopaminergic system is implicated in the pathophysiology of migraine. However, the underlying mechanisms remain unclear. We explored the effects and mechanisms of dopaminergic system modulation in the in vivo and in vitro rat models of migraine. Dopaminergic agonist apomorphine, D2 receptor antagonists metoclopramide and haloperidol and 5-HT3 receptor antagonist ondansetron alone and together were tested in nitroglycerin-induced migraine model, in vivo. Likewise, the combinations of drugs were also tested on basal calcitonin gene-related peptide (CGRP) release in vitro hemiskull preparations. Mechanical allodynia was tested by von Frey filaments. CGRP concentrations in trigeminovascular structures and in vitro superfusates and c-Fos levels in the brainstem were determined by enzyme-linked immunosorbent assay. Meningeal mast cells were evaluated with toluidine blue staining. Apomorphine further enhanced nitroglycerin-induced mechanical allodynia, brainstem c-fos expression, trigeminal ganglion and brainstem CGRP concentrations and meningeal mast cell degranulation, in vivo. Haloperidol completely antagonised all apomorphine-induced effects and also alleviated changes induced by nitroglycerin without apomorphine. Metoclopramide and ondansetron partially attenuated apomorphine- or nitroglycerin-induced effects. A combination of haloperidol and ondansetron decreased basal CGRP release, in vitro, whereas the other administrations were ineffective. Apomorphine-mediated dopaminergic activation exacerbated nitroglycerin-stimulated nociceptive reactions by further enhancing c-fos expression, CGRP release and mast cell degranulation in strategical structures associated with migraine pain. Metoclopramide partially attenuated the effects of apomorphine, most likely because it is also a 5-HT3 receptor antagonist. Haloperidol with pure D2 receptor antagonism feature appears to be more effective than metoclopramide in reducing migraine-related parameters in dopaminergic activation- and/or NTG-induced migraine-like conditions.

2.
Chem Biol Interact ; 376: 110450, 2023 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-36925032

RESUMO

Excitotoxicity and neuroinflammation are key contributors to perinatal brain injuries. Capsaicin, an active ingredient of chili peppers, is a potent exogenous agonist for transient receptor potential vanilloid 1 receptors. Although the neuroprotective and anti-inflammatory effects of capsaicin are well-documented, its effects on excitotoxic-induced neonatal brain injury and neuroinflammation have not previously been investigated. The aim of this study was to investigate the effects of capsaicin on brain damage, brain mast cells, and inflammatory mediators in a model of ibotenate-induced excitotoxic brain injury in neonatal rats. P5 rat-pups were intraperitoneally injected with vehicle, 0.2-, 1-, and 5-mg/kg doses of capsaicin, or the NMDA (N-methyl-d-aspartate) receptor antagonist MK-801 (dizocilpine), 30 min before intracerebral injection of 10 µg ibotenate. The naive-control group received no substance administration. The rat pups were sacrificed one or five days after ibotenate injection. Levels of activin A and interleukin (IL)-1ß, IL-6, and IL-10 in brain tissue were measured using the enzyme-linked immunosorbent assay method. Cortex and white matter thicknesses, white matter lesion size, and mast cells were evaluated in brain sections stained with cresyl-violet or toluidine-blue. Capsaicin improved ibotenate-induced white matter lesions and cerebral white and gray matter thicknesses in a dose-dependent manner. In addition, it suppressed the degranulation and increased number of brain mast cells induced by ibotenate. Capsaicin also reduced the excitotoxic-induced production of neuronal survival factor activin A and of the pro-inflammatory cytokines IL-1ß, and IL-6 in brain tissue. However, IL-10 levels were not altered by the treatments. MK-801, as a positive control, reversed all these ibotenate-induced changes, further confirming the success of the model. Our findings provide, for the first time, evidence for the therapeutic effects of capsaicin against excitotoxic-induced neonatal brain injury and brain mast cell-mediated neuroinflammation. Capsaicin may therefore be a promising candidate in the prevention and/or reduction of neonatal brain damage.


Assuntos
Encefalite , Mastócitos , Animais , Ratos , Animais Recém-Nascidos , Capsaicina/farmacologia , Lesões Encefálicas/induzido quimicamente , Lesões Encefálicas/tratamento farmacológico , Encefalite/induzido quimicamente , Encefalite/tratamento farmacológico , Encefalite/patologia , Substância Branca , Substância Cinzenta , Ácido Ibotênico/toxicidade , Citocinas/metabolismo
3.
Life Sci ; 313: 121300, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36535399

RESUMO

AIMS: To investigate the effects of different doses of esculetin on epileptiform activity, behavioral seizures, memory impairment, and cortical and hippocampal NF-κB, as a mediator of pro-inflammatory gene induction, and pro-inflammatory cytokines in penicillin- and pentylenetetrazole(PTZ)-induced seizure models in rats. MAIN METHODS: Different doses of esculetin (5, 10, and 20 mg/kg), and diazepam (5 mg/kg) as a positive control, were tested in penicillin- and pentylenetetrazole(PTZ)-induced seizure models. In the PTZ model, cognitive function, behavioral seizures, and cortical and hippocampal pro-inflammatory biomarkers and survival factor was evaluated. In the penicillin model, the frequency and amplitude of electrophysiological epileptiform activity were assessed. KEY FINDINGS: In the PTZ model, the 10 mg/kg esculetin displayed anticonvulsant effects by extending onset-times of myoclonic-jerk and generalized tonic-clonic seizure, and by diminishing seizure severity and duration of generalized tonic-clonic seizure. It also ameliorated PTZ-induced cognitive impairment, and cortical and hippocampal activin-A, IL-1ß, IL-6 and NF-κB levels. In the penicillin model, the 10 mg/kg esculetin decreased the frequency of spikes without changing the amplitude of spikes. As a positive-control, diazepam reversed all changes induced by both PTZ and penicillin. SIGNIFICANCE: Esculetin exhibits anticonvulsant and memory-improving effects by alleviating the behavioral and electrophysiological characteristics of epileptic seizures. Additionally, esculetin exerts anti-neuroinflammatory actions in the PTZ-induced seizures model. Thus, esculetin may be a multi-targeted promising agent with anticonvulsant and anti-neuroinflammatory effects in the treatment of epilepsy.


Assuntos
Disfunção Cognitiva , Epilepsia , Ratos , Animais , Pentilenotetrazol/toxicidade , Anticonvulsivantes/efeitos adversos , Citocinas/uso terapêutico , NF-kappa B , Convulsões/induzido quimicamente , Convulsões/tratamento farmacológico , Epilepsia/tratamento farmacológico , Diazepam/farmacologia , Disfunção Cognitiva/induzido quimicamente , Disfunção Cognitiva/tratamento farmacológico , Modelos Animais de Doenças
4.
Arq Neuropsiquiatr ; 80(12): 1220-1226, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36580959

RESUMO

BACKGROUND: The fact that inflammation triggers epileptic seizures brings to mind the antiepileptic properties of anti-inflammatory drugs. OBJECTIVE: To investigate the electrophysiological and anti-inflammatory effects of fingolimod on an experimental penicillin-induced acute epileptic seizure model in rats. METHODS: Thirty-two male Wistar rats were divided into four groups: control (penicillin), positive control (penicillin + diazepam [5 mg/kg]), drug (penicillin + fingolimod [0.3 mg/kg]) and synergy group (penicillin + diazepam + fingolimod). The animals were anesthetized with urethane, and epileptiform activity was induced by intracortical injection of penicillin (500,000 IU). After electrophysiological recording for 125 minutes, IL-1ß, TNF-α, and IL-6 were evaluated by ELISA in the serum of sacrificed animals. RESULTS: During the experiment, animal deaths occurred in the synergy group due to the synergistic negative chronotropic effect of diazepam and fingolimod. Although not statistically significant, fingolimod caused a slight decrease in spike-wave activity and spike amplitudes in the acute seizure model induced by penicillin (p > 0.05). Fingolimod decreased serum IL-1ß (p < 0.05); fingolimod and diazepam together reduced IL-6 (p < 0.05), but no change was observed in serum TNF-α values. CONCLUSION: Even in acute use, the spike-wave and amplitude values of fingolimod decrease with diazepam, anticonvulsant and anti-inflammatory effects of fingolimod will be more prominent in chronic applications and central tissue evaluations. In addition, concomitant use of fingolimod and diazepam is considered to be contraindicated due to the synergistic negative inotropic effect.


ANTECEDENTES: O fato de a inflamação desencadear crises epilépticas traz à mente as propriedades antiepilépticas dos anti-inflamatórios. OBJETIVO: Investigar os efeitos eletrofisiológicos e anti-inflamatórios do fingolimode em um modelo experimental de crise epiléptica aguda induzida por penicilina em ratos. MéTODOS: Trinta e dois ratos Wistar machos foram divididos em quatro grupos: controle (penicilina), controle positivo (penicilina + diazepam [5 mg/kg]), droga (penicilina + fingolimode [0,3 mg/kg]) e grupo sinergia (penicilina + diazepam + fingolimode). Os animais foram anestesiados com uretano, e a atividade epileptiforme foi induzida por injeção intracortical de penicilina (500.000 UI). Após registro eletrofisiológico por 125 minutos, IL-1ß, TNF-α e IL-6 foram avaliados por ELISA no soro dos animais sacrificados. RESULTADOS: Durante o experimento, ocorreram mortes de animais no grupo sinérgico devido ao efeito cronotrópico negativo sinérgico do diazepam e do fingolimode. Embora não seja estatisticamente significativo, o fingolimode causou uma ligeira diminuição na atividade pico-onda e nas amplitudes pico no modelo de convulsão aguda induzida pela penicilina (p > 0,05). O fingolimode diminuiu a IL-1ß sérica (p < 0,05); fingolimode e diazepam juntos reduziram a IL-6 (p < 0,05), mas não foi observada alteração nos valores séricos de TNF-α. CONCLUSãO: Pensa-se que o efeito anticonvulsivante leve de uma dose única de fingolimode será mais proeminente em aplicações crônicas e em avaliações de tecidos centrais. Além disso, o uso concomitante de fingolimode e diazepam é considerado contraindicado devido ao efeito inotrópico negativo sinérgico.


Assuntos
Cloridrato de Fingolimode , Penicilinas , Convulsões , Animais , Masculino , Ratos , Anti-Inflamatórios/farmacologia , Anticonvulsivantes/farmacologia , Diazepam/farmacologia , Modelos Animais de Doenças , Eletroencefalografia , Cloridrato de Fingolimode/farmacologia , Interleucina-6 , Penicilinas/efeitos adversos , Ratos Wistar , Convulsões/induzido quimicamente , Convulsões/tratamento farmacológico , Fator de Necrose Tumoral alfa , Contraindicações de Medicamentos
5.
Eur J Neurosci ; 2022 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-36485173

RESUMO

Growing evidence indicates that the parasympathetic system is implicated in migraine headache. However, the cholinergic mechanisms in the pathophysiology of migraine remain unclear. We investigated the effects and mechanisms of cholinergic modulation and a mast cell stabilizer cromolyn in the nitroglycerin-induced in vivo migraine model and in vitro hemiskull preparations in rats. Effects of cholinergic agents (acetylcholinesterase inhibitor neostigmine, or acetylcholine, and muscarinic antagonist atropine) and mast cell stabilizer cromolyn or their combinations were tested in the in vivo and in vitro experiments. The mechanical hyperalgesia was assessed by von Frey hairs. Calcitonin gene-related peptide (CGRP) and C-fos levels were measured by enzyme-linked immunosorbent assay. Degranulation and count of meningeal mast cells were determined by toluidine-blue staining. Neostigmine augmented the nitroglycerin-induced mechanical hyperalgesia, trigeminal ganglion CGRP levels, brainstem CGRP, and C-fos levels, as well as degranulation of mast cells in vivo. Atropine inhibited neostigmine-induced additional increases in CGRP levels in trigeminal ganglion and brainstem while it failed to do this in the mechanical hyperalgesia, C-fos levels, and the mast cell degranulation. However, all systemic effects of neostigmine were abolished by cromolyn. The cholinergic agents or cromolyn did not alter basal release of CGRP, in vitro, but cromolyn alleviated the CGRP-inducing effect of capsaicin while atropine failed to do it. These results ensure for a first time direct evidence that endogenous acetylcholine contributes to migraine pathology mainly by activating meningeal mast cells while muscarinic receptors are involved in CGRP release from trigeminal ganglion and brainstem, without excluding the possible role of nicotinic cholinergic receptors.

6.
Cephalalgia ; 42(13): 1375-1386, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35861239

RESUMO

BACKGROUND: Calcitonin gene-related peptide release in trigeminovascular system is a pivotal component of neurogenic inflammation underlying migraine pathophysiology. Transient receptor potential channels and voltage-gated KCNQ/Kv7 potassium channels expressed throughout trigeminovascular system are important targets for modulation of calcitonin gene-related peptide release. We investigated the effects of certain transient receptor potential (TRP) channels the vanilloid 1 and 4 (TRPV1 and TRPV4), the ankyrin 1 (TRPA1), and metastatin type 8 (TRPM8), and voltage-gated potassium channel (Kv7) opener retigabine on calcitonin gene-related peptide release from peripheral (dura mater and trigeminal ganglion) and central (trigeminal nucleus caudalis) trigeminal components of rats. METHODS: The experiments were carried out using well-established in-vitro preparations (hemiskull, trigeminal ganglion and trigeminal nucleus caudalis) from male Wistar rats. Agonists and antagonists of TRPV1, TRPV4, TRPA1 and TRPM8 channels, and also retigabine were tested on the in-vitro release of calcitonin gene-related peptide. Calcitonin gene-related peptide concentrations were measured using enzyme-linked immunosorbent assay. RESULTS: Agonists of these transient receptor potential channels induced calcitonin gene-related peptide release from hemiskull, trigeminal ganglion and trigeminal nucleus caudalis, respectively. The transient receptor potential channels-induced calcitonin gene-related peptide releases were blocked by their specific antagonists and reduced by retigabine. Retigabine also decreased basal calcitonin gene-related peptide releases in all preparations. CONCLUSION: Our findings suggest that favorable antagonists of these transient receptor potential channels, or Kv7 channel opener retigabine may be effective in migraine therapy by inhibiting neurogenic inflammation that requires calcitonin gene-related peptide release.


Assuntos
Transtornos de Enxaqueca , Canais de Potencial de Receptor Transitório , Ratos , Masculino , Animais , Peptídeo Relacionado com Gene de Calcitonina/metabolismo , Canais de Potencial de Receptor Transitório/farmacologia , Canais de Cátion TRPV , Inflamação Neurogênica , Ratos Wistar , Gânglio Trigeminal/metabolismo , Transtornos de Enxaqueca/tratamento farmacológico
7.
J Neuroimmunol ; 368: 577894, 2022 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-35642994

RESUMO

We investigated effects of activation of TRESK channels by selective activator cloxyquin on excitotoxic-induced brain injury and neuroinflammation involving brain mast cells and inflammatory cytokines in neonatal rats. Three different doses of cloxyquin (0.2, 1 and 5 mg/kg) were studied in ibotenate-induced perinatal brain injury (PBI) in P5 rat-pups. Cerebral lesions and mast cells in coronal brain sections were evaluated. Concentrations of activin A, IL-1ß, IL-6 and IL-10 in brain homogenates were measured using ELISA. Cloxyquin dose-dependently exerted protective effects against excitotoxic-induced neonatal brain injury and neuroinflammation. TRESK channels may be a promising new target for the treatment of PBIs.


Assuntos
Lesões Encefálicas , Canais de Potássio de Domínios Poros em Tandem , Canais de Potássio/metabolismo , Animais , Animais Recém-Nascidos , Lesões Encefálicas/induzido quimicamente , Lesões Encefálicas/tratamento farmacológico , Lesões Encefálicas/prevenção & controle , Cloroquinolinóis , Doenças Neuroinflamatórias , Ratos
8.
Inflammopharmacology ; 30(3): 1093-1105, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35412166

RESUMO

The present study aimed to explore the possible anti-inflammatory actions of liraglutide (LRG), a glucagon-like peptide-1 (GLP-1) receptor agonist, and to compare with tramadol (TR) or LRG, and TR combination treatment by investigating the inflammatory signs such as pain hypersensitivity, edema, and fever in carrageenan (CG)-induced acute peripheral inflammation model in rats. The levels of several biomarkers for inflammatory status, angiogenesis, and oxidative stress were also measured in inflamed tissues. CG induced inflammation in the paws of rats identified by hypersensitivities, redness, edema and fever. LRG, significantly improved the hypersensitivity to mechanical (from 4 to 35.5 g) or cold (from 5 to 44.2 s) stimuli, reduced the edema (paw mass, from 2.54 to 1.85 g), and fever (paw temperature, from 33.6 to 27.3 °C). LRG dramatically suppressed the inflammatory signs when compared to those of TR. In addition, co-administration of TR and LRG resulted in further reduction of sensitivity to mechanical and cold stimuli. Anti-inflammatory potential of LRG altered depending on their inhibitory effects in the biomarkers of inflamed paws. Consequently, the suppressive actions of LRG in the inflammation induced hypersensitivities, edema, and fever, indicating that these drugs have significant anti-inflammatory potential with anti-hypersensitivities, anti-edema, and anti-pyretic effects. LRG with anti-inflammatory actions may be a highly promising therapeutic option for the management of inflammatory conditions or inflammatory-related various diseases.


Assuntos
Hipersensibilidade , Liraglutida , Animais , Anti-Inflamatórios/uso terapêutico , Biomarcadores , Carragenina , Edema/induzido quimicamente , Edema/tratamento farmacológico , Febre/tratamento farmacológico , Receptor do Peptídeo Semelhante ao Glucagon 1/uso terapêutico , Hipersensibilidade/tratamento farmacológico , Inflamação/induzido quimicamente , Inflamação/tratamento farmacológico , Liraglutida/farmacologia , Ratos
9.
Arq Neuropsiquiatr ; 80(1): 48-55, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-35239805

RESUMO

BACKGROUND: Epilepsy has neuropsychiatric comorbidities such as depression, bipolar disorder, and anxiety. Drugs that target epilepsy may also be useful for its neuropsychiatric comorbidities. OBJECTIVE: To investigate the effects of serotonergic modulation on pro-inflammatory cytokines and the seizures in pentylenetetrazole (PTZ)-induced seizure model in rats. METHODS: Male Wistar rats were injected intraperitoneally with serotonin, selective serotonin reuptake inhibitor fluoxetine, 5-HT1B/D receptor agonist sumatriptan, or saline 30 min prior to PTZ treatment. Behavioral seizures were assessed by the Racine's scale. Concentrations of IL-1ß, IL-6, and TNF-α in serum and brain tissue were determined by ELISA. RESULTS: Serotonin and fluoxetine, but not sumatriptan, alleviated PTZ-induced seizures by prolonging onset times of myoclonic-jerk and generalized tonic-clonic seizures. The anti-seizure effect of fluoxetine was greater than that of serotonin. Likewise, serotonin and fluoxetine, but not sumatriptan, reduced PTZ-induced increases in the levels of IL-1ß and IL-6 in both serum and brain tissue. None of the administered drugs including PTZ affected TNF-α concentrations. CONCLUSIONS: Our findings suggest that endogenous and exogenous serotonin exhibits anticonvulsant effects by suppressing the neuroinflammation. It seems that 5-HT1B/D receptors do not mediate anticonvulsant and anti-neuroinflammatory effects of serotonin.


Assuntos
Epilepsia , Pentilenotetrazol , Animais , Anticonvulsivantes/efeitos adversos , Epilepsia/tratamento farmacológico , Fluoxetina/efeitos adversos , Humanos , Interleucina-6 , Masculino , Doenças Neuroinflamatórias , Pentilenotetrazol/efeitos adversos , Ratos , Ratos Wistar , Convulsões/induzido quimicamente , Convulsões/tratamento farmacológico , Serotonina/efeitos adversos , Sumatriptana/efeitos adversos , Fator de Necrose Tumoral alfa
10.
Arq. neuropsiquiatr ; 80(1): 48-55, Jan. 2022. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1360131

RESUMO

ABSTRACT Background: Epilepsy has neuropsychiatric comorbidities such as depression, bipolar disorder, and anxiety. Drugs that target epilepsy may also be useful for its neuropsychiatric comorbidities. Objective: To investigate the effects of serotonergic modulation on pro-inflammatory cytokines and the seizures in pentylenetetrazole (PTZ)-induced seizure model in rats. Methods: Male Wistar rats were injected intraperitoneally with serotonin, selective serotonin reuptake inhibitor fluoxetine, 5-HT1B/D receptor agonist sumatriptan, or saline 30 min prior to PTZ treatment. Behavioral seizures were assessed by the Racine's scale. Concentrations of IL-1β, IL-6, and TNF-α in serum and brain tissue were determined by ELISA. Results: Serotonin and fluoxetine, but not sumatriptan, alleviated PTZ-induced seizures by prolonging onset times of myoclonic-jerk and generalized tonic-clonic seizures. The anti-seizure effect of fluoxetine was greater than that of serotonin. Likewise, serotonin and fluoxetine, but not sumatriptan, reduced PTZ-induced increases in the levels of IL-1β and IL-6 in both serum and brain tissue. None of the administered drugs including PTZ affected TNF-α concentrations. Conclusions: Our findings suggest that endogenous and exogenous serotonin exhibits anticonvulsant effects by suppressing the neuroinflammation. It seems that 5-HT1B/D receptors do not mediate anticonvulsant and anti-neuroinflammatory effects of serotonin.


RESUMO Antecedentes: A epilepsia apresenta comorbidades neuropsiquiátricas como depressão, transtorno bipolar e ansiedade. Os medicamentos que visam o tratamento da epilepsia podem ser úteis para a epilepsia e suas comorbidades neuropsiquiátricas. Objetivo: Investigar os efeitos da modulação serotonérgica em citocinas pró-inflamatórias e as convulsões no modelo de convulsão induzida por pentilenotetrazol (PTZ) em ratos. Métodos: Ratos Wistar machos foram injetados intraperitonealmente com serotonina, inibidor seletivo da recaptação da serotonina fluoxetina, sumatriptano agonista do receptor 5-HT1B / D ou solução salina 30 min antes do tratamento com PTZ. As crises comportamentais foram avaliadas pela escala de Racine. As concentrações de IL-1β, IL-6 e TNF-α no soro e tecido cerebral foram determinadas por ELISA. Resultados: A serotonina e a fluoxetina, mas não o sumatriptano, aliviaram as convulsões induzidas por PTZ ao prolongar os tempos de início das convulsões mioclônicas e tônico-clônicas generalizadas. O efeito anticonvulsivo da fluoxetina foi maior do que o da serotonina. Da mesma forma, a serotonina e a fluoxetina, mas não o sumatriptano, reduziram os aumentos induzidos por PTZ nos níveis de IL-1β e IL-6 no soro e no tecido cerebral. Nenhum dos medicamentos administrados, incluindo PTZ, alterou as concentrações de TNF-α. Conclusões: Nossos achados sugerem que a serotonina endógena e exógena exibe efeitos anticonvulsivantes por suprimir a neuroinflamação. Aparentemente, os receptores 5-HT1B / D não medeiam os efeitos anticonvulsivantes e anti-neuroinflamatórios da serotonina.


Assuntos
Humanos , Animais , Masculino , Ratos , Pentilenotetrazol/efeitos adversos , Epilepsia/tratamento farmacológico , Convulsões/induzido quimicamente , Convulsões/tratamento farmacológico , Serotonina/efeitos adversos , Fluoxetina/efeitos adversos , Interleucina-6 , Fator de Necrose Tumoral alfa , Ratos Wistar , Sumatriptana/efeitos adversos , Anticonvulsivantes/efeitos adversos
11.
Eur J Neurosci ; 55(4): 1015-1031, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-32639078

RESUMO

Calcitonin gene-related peptide (CGRP), substance P and dural mast cells are main contributors in neurogenic inflammation underlying migraine pathophysiology. Modulation of endocannabinoid system attenuates migraine pain, but its mechanisms of action remain unclear. We investigated receptor mechanisms mediating anti-neuroinflammatory effects of endocannabinoid system modulation in in vivo migraine model and ex vivo hemiskull preparations in rats. To induce acute model of migraine, a single dose of nitroglycerin was intraperitoneally administered to male rats. Moreover, isolated ex vivo rat hemiskulls were prepared to study CGRP and substance P release from meningeal trigeminal afferents. We used methanandamide (cannabinoid agonist), rimonabant (cannabinoid receptor-1 CB1 antagonist), SR144528 (CB2 antagonist) and capsazepine (transient receptor potential vanilloid-1 TRPV1 antagonist) to explore effects of endocannabinoid system modulation on the neurogenic inflammation, and possible involvement of CB1, CB2 and TRPV1 receptors during endocannabinoid effects. Methanandamide attenuated nitroglycerin-induced CGRP increments in in vivo plasma, trigeminal ganglia and brainstem and also in ex vivo hemiskull preparations. Methanandamide also alleviated enhanced number and degranulation of dural mast cells induced by nitroglycerin. Rimonabant, but not capsazepine or SR144528, reversed the attenuating effects of methanandamide on CGRP release in both in vivo and ex vivo experiments. Additionally, SR144528, but not rimonabant or capsazepine, reversed the attenuating effects of methanandamide on dural mast cells. However, neither nitroglycerin nor methanandamide changed substance P levels in both in vivo and ex vivo experiments. Methanandamide modulates CGRP release in migraine-related structures via CB1 receptors and inhibits the degranulation of dural mast cells through CB2 receptors. Selective ligands targeting CB1 and CB2 receptors may provide novel and effective treatment strategies against migraine.


Assuntos
Endocanabinoides , Transtornos de Enxaqueca , Animais , Peptídeo Relacionado com Gene de Calcitonina , Masculino , Transtornos de Enxaqueca/tratamento farmacológico , Inflamação Neurogênica , Nitroglicerina , Ratos , Rimonabanto/farmacologia , Rimonabanto/uso terapêutico , Substância P
12.
Eur J Neurosci ; 55(9-10): 2912-2924, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-33565644

RESUMO

Neuroinflammation plays a key role in the pathogenesis of epilepsy, but the underlying mechanisms are not well understood. Mast cells are multifunctional immune cells that are also activated by stress. The effects of activated mast cells on epileptogenesis are not yet known. This study investigated the effects and mechanisms of compound 48/80-stimulated mast cell activation on pentylenetetrazole-induced epileptic seizures in rats. Male Wistar rats were separated into seven groups (n = 12). Group-1(NS+PTZ) received intraperitoneal saline solution, while groups 2(C-48/80+PTZ-1), 3(C-48/80+PTZ-2), and 4(C-48/80+PTZ-3) received compound-48/80 at doses of 0.5, 1, and 2 mg/kg, respectively, 30 min before 45 mg/kg pentylenetetrazole administration. Similarly, Group-5(Cr+C-48/80+PTZ) received 10 mg/kg cromolyn plus 2 mg/kg compound-48/80 before pentylenetetrazole, and Group-6(MC Dep+C-48/80+PTZ) was exposed to a mast cell-depletion process, and then received 2 mg/kg compound-48/80. Group-7(5-HT+PTZ) received 10 mg/kg serotonin. Seizure stages were evaluated using Racine's scale. Compound-48/80 at 2 mg/kg induced anticonvulsive effects against pentylenetetrazole-induced seizures by extending onset-times of both myoclonic-jerk and generalized tonic-clonic seizures (p = 0.0001), and by shortening the duration of generalized tonic-clonic seizure (p = 0.008). These effects were reversed by cromolyn (p = 0.0001). These effects were not observed in mast cell-depleted rats. Similarly to compound 48/80, serotonin also exhibited anticonvulsive effects against seizures (p < 0.05). Compound 48/80 acts as an anticonvulsant by activating mast cells in a dose-dependent manner. The anticonvulsive effects of mast cell activation may be mediated by serotonin. Mast cell activation may therefore provide protective activity against seizures under appropriate circumstances.


Assuntos
Epilepsia , Pentilenotetrazol , Animais , Anticonvulsivantes/farmacologia , Anticonvulsivantes/uso terapêutico , Cromolina Sódica/efeitos adversos , Masculino , Mastócitos , Ratos , Ratos Wistar , Convulsões/induzido quimicamente , Convulsões/tratamento farmacológico , Serotonina
13.
J Nutr Biochem ; 98: 108830, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34333116

RESUMO

Emerging evidence indicates that dysbiosis of gut microbiota plays an important role in epilepsy, although the underlying mechanisms remain unclear due to the complex nature of both microbial composition and pathophysiology of epilepsy. We investigated effects of long-term probiotics supplementation on epileptic seizures, and inflammatory and oxidant/antioxidant biomarkers in a pentylenetetrazole(PTZ)-induced seizure model in rats. Male Wistar weaner-rats were divided into four groups. The first two groups received 1 ml/day saline solution, while the other groups received 0.05 mg/1ml/day vehicle or 109cfu/1ml/day probiotic-mixture, respectively, for 60 days by gavage. Seizure was induced by a single convulsive dose of PTZ. Seizures were evaluated using Racine's scale. Concentrations of pro-inflammatory cytokines in plasma and brain tissue were determined using ELISA, while oxidant/antioxidant biomarkers were measured using an automated-colorimetric method. Probiotics supplementation exhibited anticonvulsant effects against PTZ-induced seizures by retarding onset-times of both myoclonic-jerk and generalized tonic-clonic seizure, and by shortening duration of generalized tonic-clonic seizure. Additionally, it alleviated PTZ-induced increases in levels of pro-inflammatory cytokines IL-1ß, IL-6, and IL-17A, but not of IFNγ, in plasma and brain tissue. Moreover, it restored PTZinduced fluctuations in levels of oxidants TOS and disulfide, and of antioxidants native thiol and total thiol. Our findings suggest that long-term probiotics supplementation exhibits protective effects against epileptic seizures, and alleviates (neuro)inflammation and oxidative stress related to pathophysiology of epilepsy. A probiotic-rich diet provided from childhood may provide prophylaxis against epileptic seizures, especially in susceptible individuals, as the neonate diet represents a fundamental extrinsic factor in establishing gut microbiota.


Assuntos
Inflamação/tratamento farmacológico , Estresse Oxidativo/efeitos dos fármacos , Probióticos/farmacologia , Convulsões/tratamento farmacológico , Animais , Anticonvulsivantes/farmacologia , Antioxidantes/farmacologia , Encéfalo/efeitos dos fármacos , Convulsivantes/efeitos adversos , Citocinas/metabolismo , Modelos Animais de Doenças , Epilepsia/tratamento farmacológico , Epilepsia/fisiopatologia , Microbioma Gastrointestinal/efeitos dos fármacos , Inflamação/metabolismo , Masculino , Pentilenotetrazol/efeitos adversos , Ratos , Ratos Wistar , Convulsões/metabolismo
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