Investigação da atividade antidepressiva do ortoeugenol em modelos comportamentais de depressão induzidos por dexametasona

• Autor(a) principal: Araújo, Alana Natalicia Vasconcelos de
• Data de Publicação: 2018
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: Biblioteca Digital de Teses e Dissertações da UFPB
• Texto Completo: https://repositorio.ufpb.br/jspui/handle/123456789/14761
• topic: Eugenol; Estresse; Fenilpropanoide; Mecanismo de ação; Eugenol; Stress; Phenylpropanoid; Action mechanism; CNPQ::CIENCIAS HUMANAS::PSICOLOGIA

Depression is a serious, recurring, and disabling mood disorder. It is believed that its etiology is the result of several abnormalities which interact with environmental factors, with stress being the main environment factor with impact on the emergency of the disease. Essential oils have a variety of bioactive compounds, such as phenylpropanoids. These have different pharmacological activities, such as anxiolytic, anti-inflammatory, anticonvulsant, and antidepressant, among others. Ortho-eugenol is a phenylpropanoid, a synthetic structural analogous to eugenol, which has already presented various pharmacological activities, including antidepressant activity. However, the lack of research on the possible antidepressant activities of ortho-eugenol encouraged the accomplishment of this work. This study examined the potential antidepressant activity of ortho-eugenol in adult female mice subjected to dexamethasone-induced stress model. To investigate otho-eugenol antidepressant profile, the animals were pre-administered with dexamethasone (64µg/kg s.c.) 3h30 minutes before conducting behavioral tests such as tail suspension, sucrose spraying, and open field; being ortho-eugenol (50, 75 and 100 mg/kg i.p.) and imipramine (10 mg/kg i.p.) administered 30 minutes before testing. In the tail suspension test, dexamethasone group increased immobility time of the animals, while ortho-eugenol in doses of 50 mg/kg decreased immobility time compatible with the standard drug imipramine. Ortho-eugenol, in the dose of 50 mg/kg was able to decrease latency to immobility in comparison with dexamethasone group. Next, the animals were evaluated in the sucrose spraying test, in which ortho-eugenol (50 and 100 mg/kg) increased the grooming time similarly to imipramine. Dexamethasone group increased latency to grooming, and the three doses of ortho-eugenol and imipramine decreased. Finally, the animals were submitted to the open field test to evaluate crossing number, time in the center of the field, rearing number, and latency to rearing. Ortho-eugenol, dexamethasone, and imipramine did not alter any of the open field parameters. In evaluating possible action mechanisms ortho-eugenol, the tail suspension test in doses of 50 mg/kg was chosen, which presented the best effects in the described tests. The administration of the SC23390 antagonist emphasized D1 dopaminergic receptors participation in ortho-eugenol antidepressant activity, as well as a1 adrenergic receptor with the use of prazosin antagonist, and 5-HT2A/2C serotonergic receptors with the use of antagonist ritanserin. The findings demonstrated that dexamethasona protocol was able to induce depression-simile, and that ortho-eugenol did not interfere in locomotive activity of the animals and presented a relevant antidepressant activity through D1 dopaminergic receptors and a1 adrenergic.