Inhibitory effect of Scutia buxifolia extracts, fractions, and ursolic acid on Na(+), K(+)-ATPase activity in vitro in membranes purified from rat hearts.

Scutia buxifolia is a tree native to South America and is used as a cardiotonic agent; however, this property has not been associated with a clear mechanism or a specific compound. Given the importance of Na(+),K(+)-ATPase as a drug target in the treatment of heart failure, this study aimed to investigate the possible inhibitory effect of S. buxifolia crude extract and fractions (dichloromethane, ethyl acetate, and butanolic fractions), and identified compounds with effects on the activity of Na(+),K(+)-ATPase in vitro. First, we characterized the crude extract and fractions by high-performance liquid chromatography, and then monitored their effects on the activity of Na(+),K(+)-ATPase obtained from heart muscle and brain membranes of adult male Wistar rats. We identified gallic acid, chlorogenic acid, caffeic acid, rutin, quercitrin, quercetin, and ursolic acid in S. buxifolia stem bark and leaves; quercitrin and ursolic acid were the main compounds in the ethyl acetate and dichloromethane fractions from leaves and stem bark. The crude extract (3 and 30mg/ml), and the ethyl acetate and dichloromethane fractions (0.1 and 1mg/ml) of both the stem bark and leaves inhibited Na(+),K(+)-ATPase activity in heart and brain samples. We found that, of the identified compounds, only ursolic acid (0.1mg/ml) was able to diminish Na(+), K(+)-ATPase activity in heart and brain samples. These data indicated that the cardiotonic effects of S. buxifolia may be due to the inhibition of Na(+),K(+)-ATPase activity in heart muscle, supporting the popular use of this plant as a treatment for heart failure.

Carvalho FB ，Boligon AA ，Athayde ML ，Rubin MA ，Ferreira J ，Trevisan G ... -  《-》

Biochemical and hematological effects of acute and sub-acute administration to ethyl acetate fraction from the stem bark Scutia buxifolia Reissek in mice.

Scutia buxifolia is a native tree of Southern Brazil, Uruguay, and Argentina, which is popularly known as "coronilha" and it is used as a cardiotonic, antihypertensive and diuretic substance. The aim of this study was to assess the acute and sub-acute toxicity of the ethyl acetate fraction from the stem bark Scutia buxifolia in male and female mice. The toxicity studies were based on the guidelines of the Organization for Economic Cooperation and Development (OECD-guidelines 423 and 407). In an acute study, a single dose of 2000 mg/kg of Scutia buxifolia was administered orally to male and female mice. Mortality, behavioral changes, and biochemical and hematological parameters were evaluated. In the sub-acute study, Scutia buxifolia was administered orally to male and female mice at doses of 100, 200, and 400mg/kg/day for 28 days. Behavioral changes and biochemical, hematological, and histological analysis were evaluated. The acute administration of Scutia buxifolia did not cause changes in behavior or mortality. Male and female mice presented decreased levels of platelets. Female mice presented decreased levels of leukocytes. On the other hand, in a sub-acute toxicity study, we observed no behavioral changes in male or female mice. Our results demonstrated a reduction in glucose levels in male mice treated to 200 and 400mg/kg of Scutia buxifolia. Aspartate aminotransferase (ASAT) activity was increased by Scutia buxifolia at 400mg/kg in male mice. In relation to the hematological parameters, male mice presented a reduction in hemoglobin (HGB) and hematocrit (HCT) when treated to 400mg/kg of plant fraction. Female mice showed no change in these parameters. Histopathological examination of liver tissue showed slight abnormalities that were consistent with the biochemical variations observed. Scutia buxifolia, after acute administration, may be classified as safe (category 5), according to the OECD guide. However, the alterations observed, after sub-acute administration with high doses of ethyl acetate fraction from the stem bark Scutia buxifolia, suggest that repeated administration of this fraction plant can cause adverse hepatic, renal, and hematological effects.

da Silva AR ，Moreira Lda R ，Brum Eda S ，de Freitas ML ，Boligon AA ，Athayde ML ，Roman SS ，Mazzanti CM ，Brandão R ... -  《-》

Antioxidant activities of flavonol derivatives from the leaves and stem bark of Scutia buxifolia Reiss.

Boligon AA ，Pereira RP ，Feltrin AC ，Machado MM ，Janovik V ，Rocha JB ，Athayde ML ... -  《-》

Antimicrobial and cytotoxic activities of leaves, twigs and stem bark of Scutia buxifolia Reissek.

Boligon AA ，Janovik V ，Frohlich JK ，Spader TB ，Froeder AL ，Alves SH ，Athayde ML ... -  《-》

Endothelium-dependent and independent vasorelaxation induced by an n-butanolic fraction of bark of Scutia buxifolia Reiss (Rhamanaceae).

Da Silva Rde C ，Crestani S ，de Souza P ，Boligon AA ，Athayde ML ，Santos AR ，Marques MC ，Kassuya CA ，Da Silva-Santos JE ... -  《-》