RESUMO
The present study evaluates the effect of isolated fractions of Harpagophytum procumbens (devil's claw) on cyclooxygenase (COX-1 and COX-2) activities and NO production using a whole blood assay. The activity of COX-1 was quantified as platelet thromboxane B(2) production in blood clotting and COX-2 as prostaglandin E(2) production in LPS-stimulated whole blood. Total NO(2) (-)/NO(3) (-) concentration was determined by Griess reaction in LPS stimulated blood. Assays were performed by incubation of isolated fractions obtained by flash chromatography monitored with HPLC, TLC and identified by (1)HNMR, containing different amounts of harpagoside with blood from healthy donors. Indomethacin and etoricoxib were the positive controls of COX-1 and COX-2 Inhibition. Data shows that fraction containing the highest concentration of harpagoside inhibited indistinctively COX-1 and COX-2 (37.2 and 29.5% respectively) activity and greatly inhibited NO production (66%). In contrast the fraction including iridoid pool increased COX-2 and did not alter NO and COX-1 activities. The fraction containing cinnamic acid was able to reduce only NO production (67%). Our results demonstrated that the harpagoside fraction is the main responsible for the effect of devils claw on these enzyme activities. However, other components from devil's claw crude extract could antagonize or increase the synthesis of inflammatory mediators.
Assuntos
Ciclo-Oxigenase 1/metabolismo , Ciclo-Oxigenase 2/metabolismo , Inibidores de Ciclo-Oxigenase/farmacologia , Glicosídeos/farmacologia , Harpagophytum/química , Óxido Nítrico/biossíntese , Extratos Vegetais/farmacologia , Piranos/farmacologia , Anti-Inflamatórios não Esteroides/farmacologia , Análise Química do Sangue , Coagulação Sanguínea , Plaquetas/metabolismo , Cinamatos/farmacologia , Dinoprostona/biossíntese , Etoricoxib , Feminino , Humanos , Indometacina/farmacologia , Mediadores da Inflamação/metabolismo , Iridoides/farmacologia , Lipopolissacarídeos , Piridinas/farmacologia , Sulfonas/farmacologia , Tromboxano B2/biossínteseRESUMO
OBJETIVO: O presente estudo avaliou o efeito dos extratos de H. procumbens e suas frações na atividade da COX-1 e COX-2 e produção de NO em ensaio de sangue total de voluntários sadios e pacientes com OA. MÉTODOS: A atividade da COX-1 foi determinada através da produção de TxB2 por plaquetas e da COX-2 pela produção de PGE2 por monócitos estimulados por LPS. A produção de NO2 -/NO3 - foi determinada por reação de Griess. Os ensaios in vitro foram realizados por incubação do extrato do extrato de H.procumbens e frações em sangue total. Os controles inibidores da atividade da COX-1 e COX-2 foram indometacina e etoricoxibe. A atividade enzimática das COXs e produção de NO foram avaliadas antes e após o tratamento com garra-dodiabo em pacientes com OA de coluna lombar. RESULTADOS: O tratamento com garra-do-diabo foi eficaz clinicamente e aumentou a atividade da COX-1 e COX-2 basal sem LPS. O extrato bruto do H. procumbens não alterou a atividade das COX. Entretanto, o harpagosideo inibiu a atividade da COX-1, COX-2 e a produção de NO. CONCLUSÃO: A garra-do-diabo mostrou-se eficaz no tratamento de pacientes com OA de coluna lombar. O harpagosideo deve ser alvo estudos específicos.
OBJECTIVE: The present study evaluated the effect of H. procumbens extracts and its fractions on COX-1 and COX-2 activity and NO production in whole blood assays of volunteers and OA patients. METHODS: The COX-1 and COX-2 activity was quantified as platelet TXB2 production in blood clotting and as PGE2 production in heparinized LPS-stimulated whole blood, respectively. Total NO2 -/NO3 - was determined by Griess reaction. In vitro assays were performed through incubation of the extract and fractions with whole blood from volunteers. Controls of the inhibition of COX-1 and COX-2 activity were indomethacin and etoricoxib. Before and after treating OA lumbar spine patients with devil's claw the COX-1 and COX-2 activity and NO production were evaluated in their whole blood. RESULTS: The treatment promoted clinical improvement and increase in the activity of COX-1 and basal COX-2, without LPS. The crude extract did not affect the activity of both enzymes. However, harpagoside inhibited COX-1 and COX-2 activity and NO production. CONCLUSION: Devil's claw promoted clinical improvement of OA patients and harpagoside must be focus of specific studies.