ABSTRACT
Polygala paniculata L. (Polygalaceae) é uma erva que ocorre em todas as regiões do Brasil. No presente trabalho, foram avaliadas as atividades analgésica, através do teste da placa quente, da retirada de cauda e da formalina, e antiedematogênica, através do teste do edema de orelha induzido por óleo de cróton, dos extratos etanólicos obtidos das partes aéreas de Polygala paniculata selvagem e cultivadas por micropropagação. A aplicação oral do extrato etanólico de Polygala paniculata apresentou atividade analgésica, em ratos, tanto em testes de dor induzida por agentes térmicos (testes da placa quente e de retirada da cauda) quanto por agentes químicos (teste da formalina), de modo que os melhores resultados foram obtidos na dose de 400 mg/kg. Também foi observada redução na formação de edema de orelha induzida pela aplicação de óleo de cróton. Os efeitos provocados pelos extratos obtidos a partir das plantas cultivadas in vitro foram menos pronunciados que aqueles produzidos pelos extratos das plantas selvagens, embora ambos tenham sido significativos. Estes resultados sugerem que o extrato etanólico de Polygala paniculata possui atividades analgésica e antiedematogênica.
The ethanolic extracts of Polygala paniculata L. (Polygalaceae), wich is a herbaceous plant widely distributed all over Brazil, were tested for their analgesic effects using hot plate, tail flick and formalin test models, and for their antiedematogenic effects using croton oil induced ear oedema. The ethanolic extracts obtained from wild and micropropagated plants produced analgesic effects against thermal and chemical induced pain. The highest results were observed at the dose of 400 mg/kg. The inhibition of ear oedema in mice was also observed after treatment with ethanolic extract of Polygala paniculata. The effects produced by micropropagated plants were lower than wild plants, whereas both had produced significant effects. These results suggest that the ethanolic extracts from wild and micropropagated Polygala paniculata possess analgesic and antiedematogenic effects.
ABSTRACT
Açaí (Euterpe oleracea Mart.), é uma palmeira tropical muito apreciada por sua beleza e valor nutricional. Estudos químicos revelaram a presença de ácidos graxos e esteróides. No presente trabalho foi avaliada a ação de extratos obtidos dos frutos e flores sobre a produção de óxido nítrico (ON), molécula que apresenta várias atividades fisiológicas, tais como vasodilatação, neurotransmissão, além de atividades tumoricidas e citotóxicas. Células Raw 264,7 estimuladas com lipopolissacarídeo bacteriano (LPS, 100 ng/ml) e interferon-alfa (IFN-alfa, 10 U/ml) produziram grande quantidade de óxido nítrico (35 μM) quando comparadas com as células não estimuladas (3 μM). Os extratos com hexano, diclorometano, acetato de etila e n-butanol apresentaram alta capacidade de inibição em células ativadas com LPS e IFN-alfa, de acordo com a concentração, sendo que na concentração mais alta ocorreu uma inibição de quase 100 por cento. Também avaliamos se o efeito inibitório seria devido a seqüestro do radical livre (ON), através do uso do SNAP (um doador de ON). Somente o extrato em acetato de etila mostrou atividade sequestrante. Esforços estão sendo empregados na tentativa de compreender os possíveis mecanismos associados ao efeito inibitório destes extratos.
Açaí (Euterpe oleracea Mart.) is a tropical palm tree appreciated for its attractive beauty and for nutritional purposes. Chemical studies have revealed the presence of fatty acids and steroids. In the present work, it has been tested the action of the extracts obtained from the fruits and flowers on the nitric oxide (NO) production, a very important molecule with a lot of physiological rules such as vasodilatation, neurotransmission, tumoricidal and cytotoxic activity. Cells RAW 264.7 stimulated with bacterial lipopolysaccharide (LPS, 100 ng/ml) and interferonalpha (IFN-alpha, 10 U/ml) produce large amounts of nitric oxide (35 μM) when compared with non-stimulated cells (3μM). The hexane, dichloromethane, ethyl acetate and n-butanol extracts have shown high inhibition capacity, concentration-dependent in the cells activated with LPS and IFN-alpha, and the highest concentration has promoted almost 100 percent of inhibition. We also have tested if the inhibitory effect was due to a scavenger action using a NO donor, the SNAP. Only the ethyl acetate extract has shown significant scavenger action. At this moment an effort is going on to try to understand the possible mechanisms associated to the inhibition of those extracts.
ABSTRACT
A series of new 4-acyl-arylhydrazone pyrazole compunds were tested for antinociceptive activity using the inhibition of abdominal contortions induced by acetylcholine (4 mg/Kg, ip) in the mouse. Dipyrone was used for comparison of the antinociceptive potency of the compounds being tested. All drugs wee administered po in saline (dipyrone) or in propylene flycol 94-acyl-arylhydrazones). The maximum response induced by dipyrone (86% inhibition) was assigned an efficacy index of 1.0. Although none of the compounds had an efficacy index greater than 1.0, all three reached 1.0. The two most potent compounds, Wd1 and W1g, which also had an efficacy similar to that of dipyrone, contain a p-N(CH3)2 and m-OH,p-OCH3 group in the aromatic ring of the acyl-hydrazone, respectively. W1d presented the lowest antinociceptive ED50 in the series (1.41 mg/Kg) and was eleven times more potent than dypyrone (ED50 = 15.80 mg/Kg). Other substitutions at the para position had lower potency than W1d. The present results indicate that the introduction of a group at the para postion of the acyl-arylhydrazone ring increases the antinociceptive activity of these compounds to provide compounds of the same efficacy but greater potency than dipyrone to which these new compounds ara structurally related. Other assays of nociceptive activity are veing used to characterize the mechanism of action of the potential new drugs