title: Analgesic and anti-inflammatory activities of the isomeric mixture of alpha- and beta-amyrin from Protium heptaphyllum (Aubl.) march.
abstract: In the present work, we demonstrated that the mixture of alpha- and beta-amyrin (AMI) from Protium heptaphyllum has antinociceptive activity as was evident from the writhing and formalin tests in mice. AMI (10 and 50 mg/kg, i.p.) inhibited writhing in 73 and 94%, respectively, while preferentially inhibiting the 2nd phase of the response (37 and 51; and 60 and 73% inhibitions of the 1st and 2nd phases, respectively) to the formalin test. Naloxone, an opioid antagonist, did not reverse the antinociceptive effect. AMI (50 mg/kg, i.p.) was also active in the hot plate test, increasing the reaction time to thermal stimulus after 30 and 60 min, by 62 and 71%, respectively. A preventive antiedematogenic effect was observed in mice that had a carrageenan-induced paw edema. Paw volume was significantly and dose-dependently decreased by 39, 42 and 53%, three hours after administration of 10, 25 and 50 mg/kg doses, i.p., respectively. AMI (25 and 50 mg/kg, i.p.) was also able to reverse the edema already induced by carrageenan (curative effect). AMI (10 and 25 mg/kg, i.p.) was equally effective in the dextran- induced paw edema (preventive effect), reducing the paw volume by 50 and 60% at the 2nd hour, and by 63 and 73% at the third hour post-dose. AMI (50 mg/kg, i.p.) reverted the edema already formed after the dextran injection (curative effect). In conclusion, AMI demonstrated peripheral and central analgesic effects independent of the opioid system, and also showed a potent anti-inflammatory activity. The antiinflammatory activity was potentiated by both indomethacin and thalidomide, suggesting a potential involvement of prostaglandins and TNFalpha inhibitions.
authors.affiliation: Department of Physiology and Pharmacology, Federal University of Ceará, Rua Cel. Nunes de Melo 1127, Fortaleza, 60431-970, Brazil.
authors.forename: Gislei Frota
authors.initials: GF
authors.lastname: Aragão
authors.forename: Marta Cristhiany
authors.initials: MC
authors.lastname: Cunha Pinheiro
authors.forename: Paulo
authors.initials: P
authors.lastname: Nogueira Bandeira
authors.forename: Telma Leda
authors.initials: TL
authors.lastname: Gomes Lemos
authors.forename: Glauce S
authors.initials: GS
authors.lastname: de Barros Viana
mesh_terms: D000818:Animals; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000494:pharmacology*; D002351:Carrageenan; D003911:Dextrans; D004195:Disease Models, Animal; D004305:Dose-Response Relationship, Drug; D004487:Edema / Q000139:chemically induced / Q000188:drug therapy*; D051379:Mice; D009828:Oleanolic Acid / Q000031:analogs & derivatives* / Q000494:pharmacology; D010146:Pain / Q000139:chemically induced / Q000188:drug therapy*; D010147:Pain Measurement / Q000187:drug effects; D008517:Phytotherapy
chemical_list: D000894:Anti-Inflammatory Agents, Non-Steroidal; D003911:Dextrans; D009828:Oleanolic Acid; D002351:Carrageenan; C036380:beta-amyrin