RESUMO
SUMMARY OBJECTIVE We aimed to explore the effects of neuropeptides ghrelin, obestatin, and vasoactive intestinal peptide (VIP) on seizures and plasma concentrations of neuroinflammation biomarkers including calcitonin gene-related peptide (CGRP), substance-P (SP), and interleukin-1 beta (IL-1β) in pentylenetetrazol-induced seizures in rats. METHODS Ghrelin (80 µg/kg), obestatin (1 µg/kg), VIP (25 ng/kg) or saline were administered to rats intraperitoneally 30 min before pentylenetetrazole (PTZ, 50 mg/kg) injections. Stages of epileptic seizures were evaluated by Racine's scale, and plasma CGRP, SP, and IL-1β concentrations were measured using ELISA. RESULTS Both obestatin and VIP shortened onset-time of generalized tonic-clonic seizure, respectively, moreover VIP also shortened the onset-time of first myoclonic-jerk induced by PTZ. While PTZ increased plasma CGRP, SP and IL-1β concentrations, ghrelin reduced the increases evoked by PTZ. While VIP further increased PTZ-evoked CGRP levels, it diminished IL-1β concentrations. However, obestatin did not change CGRP, SP, and IL-1β concentrations. CONCLUSION Our results suggest that ghrelin acts as an anticonvulsant, obestatin acts as a proconvulsant, and VIP has dual action on epilepsy. Receptors of those neuropeptides may be promising targets for epilepsy treatment.
RESUMO OBJETIVO Nosso objetivo foi explorar os efeitos dos neuropeptídeos grelina, obestatina e peptídeo intestinal vasoativo (VIP) nas convulsões e concentrações plasmáticas de biomarcadores neuroinflamatórios, incluindo peptídeo relacionado ao gene da calcitonina (CGRP), substância-P (SP) e interleucina-1 beta (IL-1β) em convulsões induzidas por pentilenotetrazol em ratos. MÉTODOS Grelina (80 µg/kg), obestatina (1 µg/kg), VIP (25 ng/kg) ou solução salina foram administrados a ratos intraperitonealmente 30 minutos antes de injeções de pentilenotetrazol (PTZ, 50 mg/kg). Os estágios das crises epilépticas foram avaliados pela escala de Racine e as concentrações plasmáticas de CGRP, SP e IL-1β foram medidas usando Elisa. RESULTADOS Tanto a obestatina quanto o VIP encurtaram o tempo de início da crise tônico-clônica generalizada, respectivamente. Além disso, o VIP também encurtou o tempo de início do primeiro impulso mioclônico induzido por PTZ. Enquanto o PTZ aumentou as concentrações plasmáticas de CGRP, SP e IL-1β, a grelina reduziu os aumentos evocados por PTZ. Enquanto o VIP aumenta ainda mais os níveis de CGRP evocados por PTZ, diminui as concentrações de IL-1β. No entanto, a obestatina não alterou as concentrações de CGRP, SP e IL-1β. CONCLUSÃO Nossos resultados sugerem que a grelina tem anticonvulsivante, a obestatina tem proconvulsivante e o VIP tem ação dupla na epilepsia. Receptores desses neuropeptídeos podem ser alvos promissores para o tratamento da epilepsia.
Assuntos
Animais , Masculino , Pentilenotetrazol/efeitos adversos , Convulsões/induzido quimicamente , Neuropeptídeos/efeitos adversos , Convulsivantes/efeitos adversos , Hormônios Peptídicos/farmacologia , Convulsões/metabolismo , Fatores de Tempo , Peptídeo Intestinal Vasoativo/farmacologia , Biomarcadores/sangue , Distribuição Aleatória , Substância P/efeitos adversos , Substância P/sangue , Peptídeo Relacionado com Gene de Calcitonina/efeitos adversos , Peptídeo Relacionado com Gene de Calcitonina/sangue , Ratos Wistar , Modelos Animais de Doenças , Interleucina-1beta/efeitos adversos , Interleucina-1beta/sangue , Grelina/farmacologia , Inflamação , MiocloniaRESUMO
This study reports a pharmacological evaluation of anti-inflammatory and anti-ulcer activities of carvacrol, a phenolic monoterpene constituent of essential oils produced by oregano and other several aromatic plants and spices, in experimental models of edema induced by different phlogistic agents and gastric lesions induced by acetic acid. In models of paw edema induced by dextran or histamine, carvacrol was effective at 50 mg/kg (46% and 35%, respectively); in these models, cyproheptadine reduced edema formation (61% and 43%, respectively). In edema induced by substance P, carvacrol (100 mg/kg) and ruthenium red (3 mg/kg) also decreased the edema formation (46% and 40%, respectively). Carvacrol significantly reduced the ear edema induced by 12-O-tetradecanoylphorbol acetate and arachidonic acid at 0.1 mg per ear (43% and 33%, respectively), similar to indomethacin at 0.5 mg per ear or 2.0 mg per ear (55% and 57%, respectively). Carvacrol (at doses of 25, 50, and 100 mg/kg) showed a healing capacity on gastric lesions induced by acid acetic (60%, 91%, and 81%, respectively) after 14 days of treatment. These results suggest that carvacrol acts on different pharmacological targets, probably interfering in release and/or synthesis of inflammatory mediators, such as the prostanoids, and thus favoring the healing process for gastric ulcers.
Assuntos
Anti-Inflamatórios/farmacologia , Antiulcerosos/farmacologia , Inflamação/tratamento farmacológico , Monoterpenos/farmacologia , Óleos Voláteis/farmacologia , Origanum/química , Úlcera Gástrica/tratamento farmacológico , Animais , Ácido Araquidônico/efeitos adversos , Cimenos , Edema/induzido quimicamente , Edema/tratamento farmacológico , Feminino , Indometacina/efeitos adversos , Masculino , Camundongos , Ratos , Ratos Wistar , Rutênio Vermelho/farmacologia , Úlcera Gástrica/induzido quimicamente , Substância P/efeitos adversos , Acetato de Tetradecanoilforbol/efeitos adversos , Acetato de Tetradecanoilforbol/análogos & derivadosRESUMO
UNLABELLED: The popular medicine Passiflora edulis has been used as a sedative, tranquilizer, against cutaneous inflammatory diseases and intermittent fever. Most of the pharmacological investigations of Passiflora edulis have been addressed to its Central Nervous System activities, such as anxiolytic, anticonvulsant and sedative actions. Otherwise, there are few reports about the anti-inflammatory activity of the Passiflora species. The aim of this study was to investigate the mechanism of the anti-inflammatory effect of aqueous lyophilized extract obtained from leaves of Passiflora edulis var. flavicarpa Degener (Passifloraceae) in the mouse model of pleurisy induced by carrageenan (Cg), bradykinin, histamine or substance P, observing the effects upon leucocytes migration, myeloperoxidase (MPO), nitric oxide (NO) concentrations and tumor necrosis factor-alpha (TNFalpha) and interleukin-1 beta (IL-1beta) levels. RESULTS: Passiflora edulis (250mg/kg) administered by intraperitoneal route (i.p.) inhibited the leukocyte, neutrophils, myeloperoxidase, nitric oxide, TNFalpha and IL-1beta levels (P<0.01) in the pleurisy induced by carrageenan. Passiflora edulis (250-500mg/kg, i.p.) also inhibited total and differential leukocytes in the pleurisy induced by bradykinin, histamine or substance P (P<0.05). CONCLUSION: Several mechanisms, including the inhibition of pro-inflammatory cytokines (TNFalpha, IL-1beta), enzyme (myeloperoxidase) and mediators (bradykinin, histamine, substance P, nitric oxide) release and/or action, appear to account for Passiflora edulis's actions.