In vitro evaluation of antioxidant, anxiolytic and antidepressant-like effects of the Bellis perennis extract

Acute toxicity, antioxidant activity in vitro and general pharmacological effects of the flower crude ethanolic extract of Bellis perennis L., Asteraceae, a popular medicine used in South America, were investigated in mice. The oral route LD50 value was found 2.31 g/kg. Oral administration at doses 50, 100 and 150 mg/kg of the extract neither caused significant changes in general behavior nor led to toxic symptoms. Anxiolytic-like properties were studied in the open field test and the possible antidepressant-like actions were evaluated in the forced swimming test (FST). There is a significant decrease in the number of crossings at all dosages mentioned above, but no sedative effects at any dosages when compared to controls. In the FST, the extract dosage of 150 mg/kg was effective in reducing immobility, along with a significant increase in swimming time. The ethanolic extract showed strong antioxidant potential in vitro, through the removal capacity against hydroxyl radicals and nitric oxide as well as prevented the formation of reactive substances to thiobarbituric acid (TBARS). Together, these results indicate that the ethanolic extract has effect on central nervous system, which might due to its antioxidant property, as demonstrated in vitro methods used. These results suggest that some of the components in ethanolic extract of B. perennis, such as alkaloids, phenolic compounds and flavonoids may have antioxidant, anxiolytic and antidepressant-like properties. Additional investigations are in progress.

Chemical composition and anxiolytic-like effects of the Bauhinia platypetala

The pantropical genus Bauhinia, Fabaceae, known popularly as cow's foot, is widely used in folk medicine as antidiabetic. Behavioral effects of the ethanolic extract and ethereal, aqueous and ethyl acetate fractions from B. platypetala Benth. ex Hemsl. leaves were studied in male Swiss mice. The ethanolic extract and fractions were administered intraperitoneally and its effects on spontaneous motor activity (total motility, locomotion, rearing and grooming behavior) were monitored. Anxiolytic-like properties were studied in the elevated plus-maze test and the possible antidepressant-like actions were evaluated in the forced swimming test. The results revealed that only the highest dose of the ethereal fraction (50 mg/kg, i.p.) caused a significant decrease in total motility, locomotion and rearing. Sole dose injected (50 mg/kg) of ethanolic extract and ethereal fractions increased the exploration of the elevated plus-maze open arms in a similar way to that of diazepam (2 mg/kg, i.p.). In the forced swimming test, the ethanolic extract and their fractions (12.5, 25 or 50 mg/kg) was not as effective as paroxetine (10 or 20 mg/kg, i.p.) and imipramine (25 or 50 mg/kg, i.p.) in reducing immobility. These results suggest that some of the components of the ethanolic extract and of the ethereal fraction from B. platypetala, such as p-cymene, phytol, D-lactic acid, hexadecanoic acid, among others, may have anxiolytic-like properties, which deserve further investigation. Furthermore, the results obtained indicate that ethanolic extract from B. platypetala and their fractions do not present antidepressive properties. However, these properties cannot be related to the chemical constituents identified in this specie.

Estudos comportamentais e das alterações histopatológicas em camundongos pré-tratados com Bellis perennis no modelo de convulsão induzido por pilocarpina / Behavioral studies and histopathological changes in mice pretreated with Bellis perennis in pilocarpine-induced seizures

The aim of this study was to investigate the potential neuroprotective and anticonvulsant effects of ethanolic extract from flowers (EEF) of B. perrenis in adult Swiss mice (2 months old) after seizures induced by pilocarpine. The animals were divided into 8 groups. The first group was treated with vehicle (0.05 percent Tween 80 dissolved in 0.9 percent saline) and the second with pilocarpine (400 mg/kg, P400 group). The third, fourth and fifth group were pretreated with EEF (50, 100 or 150 mg/kg) and 30 min later received P400 (EEF 50, EEF 100 or EEF 150 plus P400 groups), respectively. In turn, the remaining groups were treated with EEF alone (50, 100 or 150 mg/kg EEF 50, EEF 100 or EEF 150 groups), respectively. After treatment, the groups were observed for 24 h and then euthanized and their brains removed for histopathological analysis. All P400 group animals showed seizures that progressed to status epilepticus. Pre-treatment with EEF produced a significant reduction in those indices. P400 and EEF 50 plus P400 groups showed 87.5 percent and 37.5 percent of animals with brain damage in the hippocampus, respectively. In P400 group, the damage rate in striatum was 75 percent. In turn, this region has seen a reduction of 46.99 percent neuronal damage of those of EEF 50 plus P400 group. According to our results we suggest that the EEF may modulate epileptogenesis and promote anticonvulsant and neuroprotective mechanisms in model of seizures induced by pilocarpine.

O objetivo desse estudo foi investigar o potencial efeito neuroprotetor e anticonvulsivante do extrato etanólico das flores de B. perrenis (EEF) em camundongos Swiss adultos (2 meses) após convulsão induzida por pilocarpina. Os animais foram divididos em 8 grupos. O primeiro grupo foi tratado com veículo (Tween 80 0,05 por cento dissolvido em salina 0,9 por cento) e o segundo com pilocarpina (400 mg/kg, grupo P400). Já o terceiro, quarto e quinto grupo foram tratados com EEF (50, 100 ou 150 mg/kg), e 30 min depois receberam P400 (grupos EEF 50, EEF 100 ou EEF 150 plus P400), respectivamente. Por sua vez, os demais grupos foram tratados somente com EEF (50, 100 ou 150 mg/kg; grupos EEF 50, EEF 100 ou EEF 150), respectivamente. Após os tratamentos, os grupos foram observados durante 24 h e em seguida eutanasiados e seus cérebros removidos para as análises histopatológicas. Todos os animais do grupo P400 apresentaram convulsões que progrediram para o estado de mal epiléptico. O pré-tratamento com EEF produziu uma redução significativa nesses índices. Os grupos P400 e EEF 50 plus P400 apresentaram 87,5 por cento e 37,5 por cento de animais com lesão cerebral no hipocampo, respectivamente. No corpo estriado dos animais do grupo P400 houve um comprometimento de 75 por cento. Por sua vez, nessa região foi vista uma redução de 46,99 por cento nesse comprometimento nos animais do grupo EEF 50 plus P400. De acordo com nossos resultados podemos sugerir que o EEF pode modular a epileptogênese e promover ação neuroprotetora e anticonvulsivante no modelo das convulsões induzidas por pilocarpina.