Effect of Stryphnodendron adstringens (barbatimão) on energy metabolism in the rat liver.
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.
Rebecca
Marcelo Alessandro
MA
Laboratory of Inflammation, Department of Pharmacy and Pharmacology, University of Maringá, Avenida Colombo, 5790, CEP-87020-900, Maringá-Pr, Brazil.
Ishii-Iwamoto
Emy Luiza
EL
Kelmer-Bracht
Ana Maria
AM
Caparroz-Assef
Silvana Martins
SM
Cuman
Roberto Kenji Nakamura
RK
Pagadigorria
Clairce Luzia Salgueiro
CL
de Mello
João Carlos Palazzo
JC
Bracht
Adelar
A
Bersani-Amado
Ciomar Aparecida
CA
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
D010936:Plant Extracts; D011506:Proteins; D000244:Adenosine Diphosphate; D006003:Glycogen; D000251:Adenosine Triphosphatases