title: Gastroprotective mechanisms of the chloroform and ethyl acetate phases of Praxelis clematidea (Griseb.) R.M.King & H.Robinson (Asteraceae).
abstract: Flavonoid-rich Praxelis clematidea (Griseb.) R.M.King & H.Robinson (Asteraceae) is a native plant of South America. This study evaluates the gastroprotective activity and possible mechanisms for both the chloroform (CHCl3P) and ethyl acetate phases (AcOEtP) obtained from aerial parts of the plant. The activity was investigated using acute models of gastric ulcer. Gastric secretion biochemical parameters were determined after pylorus ligature. The participation of cytoprotective factors such as mucus, nitric oxide (NO), sulfhydryl (SH) groups, prostaglandin E2 (PGE2), reduced glutathione (GSH), superoxide dismutase (SOD), glutathione peroxidase (GPx), glutathione reductase (GR), reduction of lipid peroxidation (malondialdehyde level), and polymorphonuclear infiltration (myeloperoxidase activity), was also investigated. CHCl3P (125, 250, and 500 mg/kg) and AcOEtP (62.5, 125, and 250 mg/kg) showed significant gastroprotective activity, reducing the ulcerative index by 75, 83, 88% and 66, 66, 81% for ethanol; 67, 67, 56% and 56, 53, 58% for a non-steroidal anti-inflammatory drug (NSAID); and 74, 58, 59% and 64, 65, 61% for stress-induced gastric ulcer, respectively. CHCl3P (125 mg/kg) and AcOEtP (62.5 mg/kg) significantly reduced the ulcerative area by 78 and 83%, respectively, for the ischemia-reperfusion model. They also did not alter the biochemical parameters of gastric secretion, the GSH level or the activities of SOD, GPx or GR. They increased the quantity of gastric mucus, not dependent on NO, yet dependent on SH groups, and maintained PGE2 levels. The P. clematidea phases demonstrated gastroprotective activity related to cytoprotective factors.
authors.affiliation: Laboratório de Tecnologia Farmacêutica (LTF), Departamento de Ciências Farmacêuticas, Centro de Ciências da Saúde, Universidade Federal da Paraiba (UFPB), Cx. Postal 5009, João Pessoa, PB, CEP 58051-970, Brazil.
authors.forename: Heloina de Sousa
authors.initials: Hde S
authors.lastname: Falcão
authors.forename: Gabriela Lemos de Azevedo
authors.initials: GL
authors.lastname: Maia
authors.forename: Flávia
authors.initials: F
authors.lastname: Bonamin
authors.forename: Hélio
authors.initials: H
authors.lastname: Kushima
authors.forename: Thiago Mello
authors.initials: TM
authors.lastname: Moraes
authors.forename: Clélia Akiko
authors.initials: CA
authors.lastname: Hiruma Lima
authors.forename: Christiane
authors.initials: C
authors.lastname: Takayama
authors.forename: Anderson Luiz
authors.initials: AL
authors.lastname: Ferreira
authors.forename: Alba Regina Monteiro
authors.initials: AR
authors.lastname: Souza Brito
authors.forename: Maria de Fátima
authors.initials: Mde F
authors.lastname: Agra
authors.forename: José Maria
authors.initials: JM
authors.lastname: Barbosa Filho
authors.forename: Leônia Maria
authors.initials: LM
authors.lastname: Batista
mesh_terms: D000085:Acetates / Q000737:chemistry; D000818:Animals; D000897:Anti-Ulcer Agents / Q000302:isolation & purification / Q000494:pharmacology*; D019659:Asteraceae / Q000737:chemistry*; D015415:Biomarkers / Q000378:metabolism; D002725:Chloroform / Q000737:chemistry; D019610:Cytoprotection; D004195:Disease Models, Animal; D004353:Drug Evaluation, Preclinical; D000431:Ethanol; D005753:Gastric Mucosa / Q000187:drug effects* / Q000378:metabolism / Q000473:pathology; D008297:Male; D051379:Mice; D009093:Mucus / Q000378:metabolism; D008517:Phytotherapy; D010894:Piroxicam; D035261:Plant Components, Aerial; D010936:Plant Extracts / Q000302:isolation & purification / Q000494:pharmacology*; D010946:Plants, Medicinal; D051381:Rats; D017208:Rats, Wistar; D015427:Reperfusion Injury / Q000378:metabolism / Q000473:pathology / Q000517:prevention & control*; D015398:Signal Transduction / Q000187:drug effects; D012997:Solvents / Q000737:chemistry; D013276:Stomach Ulcer / Q000139:chemically induced / Q000378:metabolism / Q000473:pathology / Q000517:prevention & control*
chemical_list: D000085:Acetates; D000897:Anti-Ulcer Agents; D015415:Biomarkers; D010936:Plant Extracts; D012997:Solvents; D010894:Piroxicam; D000431:Ethanol; C007650:ethyl acetate; D002725:Chloroform