Antinociceptive effect of ethanolic extract of Selaginella convoluta in mice.

BACKGROUND: Selaginella convoluta (Arn.) Spring (Selaginellaceae), commonly known as "jericó", is a medicinal plant found in northeastern Brazil. S. convoluta is used in folk medicine as an antidepressant, aphrodisiac, diuretic, analgesic, anti-inflammatory and it is used to combat amenorrhea, coughing and bleeding. This study was performed to evaluate the antinociceptive effects of ethanolic extract from S. convoluta in mice exposed to chemical and thermal models of nociception. METHODS: Preliminary phytochemical analysis of the ethanolic extract was performed. The ethanolic extract from Selaginella convoluta (Sc-EtOH) was examined for its intraperitoneal (i.p.) antinociceptive activity at the doses of 100, 200 and 400 mg/kg body weight. Acetic acid-induced writhing, formalin injection and hot plate tests were used to evaluate the antinociceptive activity of Sc-EtOH extract. The rota-rod test was used to evaluate motor coordination. RESULTS: A preliminary analysis of Sc-EtOH revealed that it contained phenols, steroids, terpenoids and flavonoids. In the acetic acid-induced writhing test, mice treated with Sc-EtOH (100, 200 and 400 mg/kg, i.p.) exhibited reduced writhing (58.46, 75.63 and 82.23%, respectively). Secondly, Sc-EtOH treatment (100, 200 and 400 mg/kg, i.p.) decreased the paw licking time in mice during the first phase of the formalin test (by 44.90, 33.33 and 34.16%, respectively), as well as during the second phase of the test (by 86.44, 56.20 and 94.95%, respectively). Additionally, Sc-EtOH treatment at doses of 200 and 400 mg/kg increased the latency time in the hot plate test after 60 and 90 minutes, respectively. In addition, Sc-EtOH did not impair motor coordination. CONCLUSION: Overall, these results indicate that Sc-EtOH is effective as an analgesic agent in various pain models. The activity of Sc-EtOH is most likely mediated via the inhibition of peripheral mediators and central inhibitory mechanisms. This study supports previous claims of traditional uses for S. convoluta.

Phythochemical screening and antimicrobial activity phythochemical of essential oil from Lippia gracillis

The chemical composition of the essential oil obtained from the fresh and dried leaves of Lippia gracillis Schauer, Verbenaceae, was analyzed by gas chromatography and gas chromatography/mass spectrometry (GC⁄MS). The yield of essential oil extracted from the dried leaves was significantly higher (p<0.05) when compared to the fresh leaves. Seventeen components were identified. The monoterpenes and sesquiterpene hydrocarbons with 96.26 percent (w/w) of the total oil obtained of fresh leaves and 86.99 percent (w/w) of the total oil obtained of dried leaves were the principal compound groups. Thymol was observed dominant (44.42 percent; 21.3 percent), followed by carvacrol (22.21 percent; 21.30 percent), p-cymene (6.23 percent; 8.58 percent), α-pinene (5.65 percent; 19.42 percent), β-caryophyllene (5.61 percent; 3.57 percent) and other minor constitutes, respectively. Microbiological results obtained by agar diffusion method, micro dilution method and minimum inhibitory concentration (MIC) showed that the essential oil has a relevant antimicrobial activity against E. coli (ATCC 10536), E. coli (Ec 27), Pseudomonas aeruginosa (ATCC 15442), S. aureus (ATCC 12692) and S. aureus (Sa 358), with their inhibition zones ranging from 9 to 13 mm and the MIC ranging from 64 to 512 μg/mL.

O papel dos canais iônicos nas epilepsias e considerações sobre as drogas antiepilépticas: uma breve revisão / Ion channels role in epilepsy and considers of the antiepileptic drugs: a short review

INTRODUÇÃO: A epilepsia é um transtorno neurológico que chega a afetar cerca de 1 por cento da população mundial. Muitas formas de epilepsias não conseguem ser tratadas adequadamente com os fármacos atualmente utilizados na clínica e o desenvolvimento de novas propostas terapêuticas que as tratem, não apenas de forma sintomática, mas em sua gênese, é uma busca constante de novos estudos. OBJETIVO E DISCUSSÃO: Nesse sentido, a presente revisão busca fazer um breve levantamento sobre os aspectos científicos mais consistentes acerca do papel dos canais iônicos no desenvolvimento das epilepsias, bem como correlacionar com o estudo de drogas antiepilépticas (DAEs) e mostrar as principais características farmacológicas das DAEs mais utilizadas na clínica atualmente. O papel dos canais de Na+ e Ca+2 como alvo de novas DAEs e a participação de outros receptores nesse processo são igualmente discutidos. CONCLUSÃO: A compreensão da fisiopatologia das epilepsias e dos possíveis alvos moleculares para novos fármacos é um dos principais focos para o descobrimento de tratamentos mais eficazes e com menos efeitos adversos.

INTRODUCTION: Current epidemiological studies show a prevalence rate for active epilepsy in 0,5-1 percent of the population. Many forms of epilepsy are intractable to current therapies and there is a pressing need to develop agents and strategies to not only suppress seizures, but also cure epilepsy. OBJECTIVE AND DISCUSSION: The aim of this review was to the recent advances in the physiology of ion channels and other potential molecular targets, in conjunction with new informations on the genetics of idiopathic epilepsies, and current antiepileptic drugs (AEDs). Marketed AEDs predominantly target voltage-gated cation channels (the a-subunits of voltage gated Na+ channels and also T-type voltage-gated Ca2+ channels) or influence GABA-mediated inhibition. CONCLUSION: The growing understanding of the pathophysiology of epilepsy and the structural and functional characterization of the molecular targets provide many opportunities to create improved epilepsy therapies.