RESUMO
Since its role in inflammatory diseases was recognized, nitric oxide (NO) has become an important mediator to evaluate anti-inflammatory agents. Sesquiterpene lactones, which occur in several medicinal plants, inhibit the NO production in macrophage-like cells. This action is probably due to a 1,4 addition reaction between its alpha,beta-unsaturated carbonyl group with sulfhydryl (SH)-containing compounds. For this reason it is believed that these compounds are cytotoxic, which restricts their therapeutic use. In this contribution, the ability of the ambrosanolide-type sesquiterpene lactone cumanin (from the Asteraceae Ambrosia psilostachya) to inhibit NO biosynthesis was evaluated in lipopolisaccharide-induced peritoneal murine macrophages and its cytotoxicity was assessed in the MTT assay. Cumanin showed a potent inhibitory effect in NO production (IC(50) = 9.38+/-0.38 microM) with low cytotoxicity. The 1,4-addition reaction of thiols was slow, which does not explain the inhibition of NO production but does explain the low cytotoxicity of cumanin with respect to other lactones.
Assuntos
Ambrosia , Macrófagos Peritoneais/efeitos dos fármacos , Óxido Nítrico/antagonistas & inibidores , Óxido Nítrico/biossíntese , Animais , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Macrófagos Peritoneais/metabolismo , Masculino , Camundongos , Componentes Aéreos da Planta , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/farmacologia , Sesquiterpenos/química , Sesquiterpenos/isolamento & purificação , Sesquiterpenos/farmacologiaRESUMO
The dried aqueous extract of aerial parts of Cirsium subcoriaceum (Asteraceae) and its major flavonoid glycoside, pectolinarin, have been evaluated for analgesic and anti-inflammatory effects in mice and rats, respectively. Both the extract and pectolinarin exerted significant and dose-dependent analgesic and anti-inflammatory activities. Also, the anti-inflammatory activities of an aqueous extract of Buddleia cordata and its principal glycoside linarin were evaluated. The results of pharmacological testing proved that linarin is a better anti-inflammatory agent than pectolinarin and indomethacin. On the other hand, pectolinarin exerted a better analgesic effect than linarin.