title: Effect of isolated fractions of Harpagophytum procumbens D.C. (devil's claw) on COX-1, COX-2 activity and nitric oxide production on whole-blood assay.
abstract: 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.
authors.affiliation: Faculdade de Medicina da Universidade de São Paulo, Department of Internal Medicine, Rheumatology Division, São Paulo, Brazil.
authors.forename: Maria Cecilia
authors.initials: MC
authors.lastname: Anauate
authors.forename: Luce Maria
authors.initials: LM
authors.lastname: Torres
authors.forename: Suzana Beatriz Veríssimo
authors.initials: SB
authors.lastname: de Mello
mesh_terms: D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000494:pharmacology; D001774:Blood Chemical Analysis; D001777:Blood Coagulation; D001792:Blood Platelets / Q000378:metabolism; D002934:Cinnamates / Q000494:pharmacology; D051545:Cyclooxygenase 1 / Q000378:metabolism*; D051546:Cyclooxygenase 2 / Q000378:metabolism*; D016861:Cyclooxygenase Inhibitors / Q000494:pharmacology*; D015232:Dinoprostone / Q000096:biosynthesis; D000077613:Etoricoxib; D005260:Female; D006027:Glycosides / Q000494:pharmacology*; D031684:Harpagophytum / Q000737:chemistry*; D006801:Humans; D007213:Indomethacin / Q000494:pharmacology; D018836:Inflammation Mediators / Q000378:metabolism; D039823:Iridoids / Q000494:pharmacology; D008070:Lipopolysaccharides; D009569:Nitric Oxide / Q000096:biosynthesis*; D010936:Plant Extracts / Q000494:pharmacology*; D011714:Pyrans / Q000494:pharmacology*; D011725:Pyridines / Q000494:pharmacology; D013450:Sulfones / Q000494:pharmacology; D013929:Thromboxane B2 / Q000096:biosynthesis
chemical_list: D000894:Anti-Inflammatory Agents, Non-Steroidal; D002934:Cinnamates; D016861:Cyclooxygenase Inhibitors; D006027:Glycosides; D018836:Inflammation Mediators; D039823:Iridoids; D008070:Lipopolysaccharides; D010936:Plant Extracts; D011714:Pyrans; D011725:Pyridines; D013450:Sulfones; C029010:cinnamic acid; D009569:Nitric Oxide; D013929:Thromboxane B2; C033249:harpagoside; D051545:Cyclooxygenase 1; D051546:Cyclooxygenase 2; D015232:Dinoprostone; D000077613:Etoricoxib; D007213:Indomethacin