Omega-3 fatty acids: possible neuroprotective mechanisms in the model of global ischemia in rats

Background. Omega-3 (omega 3) administration was shown to protect against hypoxic-ischemic injury. The objectives were to study the neuroprotective effects of omega 3, in a model of global ischemia. Methods. Male Wistar rats were subjected to carotid occlusion (30 min), followed by reperfusion. The groups were SO, untreated ischemic and ischemic treated rats with omega 3 (5 and 10 mg/kg, 7 days). The SO and untreated ischemic animals were orally treated with 1% cremophor and, 1 h after the last administration, they were behaviorally tested and euthanized for neurochemical (DA, DOPAC, and NE determinations), histological (Fluoro jade staining), and immunohistochemical (TNF-alpha, COX-2 and iNOS) evaluations. The data were analyzed by ANOVA and Newman-Keuls as the post hoc test. Results. Ischemia increased the locomotor activity and rearing behavior that were partly reversed by omega 3. Ischemia decreased striatal DA and DOPAC contents and increased NE contents, effects reversed by omega 3. This drug protected hippocampal neuron degeneration, as observed by Fluoro-Jade staining, and the increased immunostainings for TNF-alpha, COX-2, and iNOS were partly or totally blocked by omega 3. Conclusion. This study showed a neuroprotective effect of omega 3, in great part due to its anti-inflammatory properties, stimulating translational studies focusing on its use in clinic for stroke managing.Faculty of Medicine, Estácio of Juazeiro do Norte (FMJ), Rua Tenente Raimundo Rocha 515, 63040-360 Juazeiro do Norte, CE, BrazilFederal University of Ceará (UFC), Rua Coronel Nunes de Melo 1127, 60430-270 Fortaleza, CE, BrazilFederal University of São Paulo (UNIFESP), Rua Pedro de Toledo 669, 04039-032 São Paulo, SP, BrazilFederal University of São Paulo (UNIFESP), Rua Pedro de Toledo 669, 04039-032 São Paulo, SP, BrazilWeb of Scienc

Antidepressant-Like Effect of Lippia sidoides CHAM (Verbenaceae) Essential Oil and Its Major Compound Thymol in Mice

Depression is a common disease affecting more than 300 million people worldwide. Since Lippia sidoides has shown central nervous system effects in previous works, we aimed to investigate the effect of L. sidoides essential oil and its major compound, thymol on a corticosterone-induced depression model in mice. Male mice (20–25 g) received corticosterone (20 mg/kg, subcutaneously), once a day for 22 days. From the 16th day on, mice were grouped to receive either corticosterone or L. sidoides essential oil (100 and 200 mg/kg), or thymol (25 and 50 mg/kg) or fluoxetine (35 mg/kg) by gavage. The forced swimming test, tail suspension, open field, elevated plus maze and sucrose preference tests were performed from the 19th to 22nd day. Data were analyzed by ANOVA followed by the Student-Newman-Keuls as a post hoc test and the results were considered significant when p < 0.05. It was shown that L. sidoides essential oil, thymol and fluoxetine decreased the immobility time in the tail suspension and forced swimming tests and none of these altered locomotor activity in the open field test. However, the drugs increased the amount of grooming. In the elevated plus maze, all drugs increased the number of entries and the time of permanence in the open arms. In the sucrose preference test, the L. sidoides essential oil, thymol and fluoxetine reversed anhedonia. These results suggest that the thymol and L. sidoides essential oil have an antidepressant-like effect, similar to fluoxetine. However, future studies should be encouraged to enhance understanding of the effects of essential oil and thymol for the treatment of depression