title: Effect of Stryphnodendron adstringens (barbatimão) on energy metabolism in the rat liver.
abstract: The action of a barbatimão extract on hepatic energy metabolism was investigated using isolated mitochondria and the perfused rat liver. In mitochondria the barbatimão extract inhibited respiration in the presence of ADP and succinate. Stimulation occurred, however, after ADP phosphorylation (state IV respiration). The ADP/O and respiratory control ratios were reduced. The activities of succinate-oxidase, NADH-oxidase and the oxidation of ascorbate were inhibited. The ATPase of intact mitochondria was stimulated, but the ATPases of uncoupled and disrupted mitochondria were inhibited. In perfused livers the extract caused stimulation of oxygen consumption, inhibition of gluconeogenesis and stimulation of glycolysis. Glucose release due to glycogenolysis was stimulated shortly after the introduction of the extract, but inhibition gradually developed as the infusion was continued. Apparently the barbatimão extract impairs the hepatic energy metabolism by three mechanisms: (1) uncoupling of oxidative phosphorylation, (2) inhibition of mitochondrial electron transport, and (3) inhibition of ATP-synthase.
authors.affiliation: Laboratory of Inflammation, Department of Pharmacy and Pharmacology, University of Maringá, Avenida Colombo, 5790, CEP-87020-900, Maringá-Pr, Brazil.
authors.forename: Marcelo Alessandro
authors.initials: MA
authors.lastname: Rebecca
authors.forename: Emy Luiza
authors.initials: EL
authors.lastname: Ishii-Iwamoto
authors.forename: Ana Maria
authors.initials: AM
authors.lastname: Kelmer-Bracht
authors.forename: Silvana Martins
authors.initials: SM
authors.lastname: Caparroz-Assef
authors.forename: Roberto Kenji Nakamura
authors.initials: RK
authors.lastname: Cuman
authors.forename: Clairce Luzia Salgueiro
authors.initials: CL
authors.lastname: Pagadigorria
authors.forename: João Carlos Palazzo
authors.initials: JC
authors.lastname: de Mello
authors.forename: Adelar
authors.initials: A
authors.lastname: Bracht
authors.forename: Ciomar Aparecida
authors.initials: CA
authors.lastname: Bersani-Amado
mesh_terms: D000244:Adenosine Diphosphate / Q000378:metabolism; D000251:Adenosine Triphosphatases / Q000378:metabolism; D000818:Animals; D001938:Brazil; D002462:Cell Membrane / Q000187:drug effects / Q000201:enzymology; D004734:Energy Metabolism / Q000187:drug effects*; D007887:Fabaceae / Q000737:chemistry*; D005943:Gluconeogenesis / Q000187:drug effects; D006003:Glycogen / Q000096:biosynthesis; D066298:In Vitro Techniques; D008099:Liver / Q000187:drug effects / Q000201:enzymology / Q000378:metabolism*; D008297:Male; D008930:Mitochondria, Liver / Q000187:drug effects / Q000201:enzymology / Q000378:metabolism; D010101:Oxygen Consumption / Q000187:drug effects; D010477:Perfusion; D024301:Plant Bark / Q000737:chemistry; D010936:Plant Extracts / Q000494:pharmacology; D010946:Plants, Medicinal / Q000737:chemistry*; D011506:Proteins / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar
chemical_list: D010936:Plant Extracts; D011506:Proteins; D000244:Adenosine Diphosphate; D006003:Glycogen; D000251:Adenosine Triphosphatases