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 ... -  《-》

Hypotensive and diuretic effect of the butanolic soluble fraction of the hydroethanolic extract of bark of Scutia buxifolia Reissek in rats.

Scutia buxifolia, a native tree popularly known as "coronilha", is widely used in Brazilian folk medicine for diuretic and anti-hypertensive purposes. We investigated the effects of a butanolic (BuOH) soluble fraction of the hydroethanolic extract (HESB) of bark of Scutia buxifolia on both blood pressure and urinary excretion of rats. The involvement of the nitric oxide/guanylate cyclase pathway in the hypotensive effect found was also explored. We tested the effect of the BuOH soluble fraction of HESB on the mean arterial pressure (MAP) of anesthetized rats. The fraction was administered at doses of 1, 3 and 10mg/kg (i.v.) in normotensive rats during continuous infusion of vehicle (10 μl/min), or phenylephrine (4 μg/kg/min), or l-NAME (7 mg/kg/min), two approaches able to induce a sustained hypertensive state. In some experiments, a bolus injection of ODQ (2mg/kg) was administered in animals infused with phenylephrine before the administration of the BuOH soluble fraction of HESB. We also measured the effects of the BuOH soluble fraction on the MAP of spontaneously hypertensive rats (SHR). Separate groups of rats were treated orally with either HESB (10, 30 or 100mg/kg), or its BuOH soluble fraction (3, 10 or 30 mg/kg), and were subjected to measurement of diuresis and blood pressure. The BuOH soluble fraction of HESB (10mg/kg, i.v.) reduced the MAP of both phenylephrine-infused and SHR rats by 20.6 ± 6.0 and 41.8 ± 8.3 mm Hg, respectively. However, no hypotensive effect was found in normotensive animals infused with l-NAME, a non-selective inhibitor of nitric oxide synthase, or animals previously treated with the soluble guanylate cyclase inhibitor ODQ. The urinary excretion was increased by 70% at 6-8h after a single oral administration of the BuOH soluble fraction of HESB (10mg/kg), without change in urinary density, pH, or Na(+) and K(+) concentrations. In addition, MAP was lower 3h after the acute oral treatment with the BuOH soluble fraction (82.1 ± 3.8 mm Hg), compared with MAP of animals from the control group (97 ± 3.2 mm Hg). This study demonstrates that the BuOH soluble fraction of the hydroethanolic bark of Scutia buxifolia, which has its bark used in folk medicine for the treatment of hypertension mainly by its presumed diuretic properties, possesses both diuretic and hypotensive effects in rats, and that at least the hypotensive effect is fully dependent on activation of the nitric oxide/guanylate cyclase pathway.

Da Silva Rde C ，de Souza P ，Crestani S ，Gasparotto Júnior A ，Boligon AA ，Athayde ML ，da Silva-Santos JE ... -  《-》

Evaluation of acute and subacute toxicity of hydroethanolic extract of Dolichandra unguis-cati L. leaves in rats.

Dolichandra unguis-cati L. is a native climbing plant of Brazil, popularly known as "unha de gato". It has been traditionally used mainly as an antipyretic, anti-inflammatory and anti-tumor agent, yet little toxicological information is found in the literature. To identify the chemical composition of the hydroethanolic extract obtained from the leaves of Dolichandra uniguis-cati and to evaluate the acute and subacute toxicity in male and female rats, in order to assess the safety profile of this plant. In the acute study, a single dose (2000mg/kg) of the extract was orally administered to male and female rats. In the subacute study, the extract was orally administered to male and female rats at doses 100, 200 and 400mg/kg for 28 days. Behavioral changes, catalase and tbars evaluations, biochemical, hematological and histopathological analysis were determined. The extract' chemical composition was accessed through UHPLC/MS. Chlorogenic acid, caffeic acid, ferulic acid, vanillinic acid, p-coumaric acid, rosmarinic acid, trans-cinnamic acid, luteolin, apigenin, quercitrin and quercetin were identified in the extract. In the acute treatment, the extract was classified as safe (category 5), according to the OECD guide. In relation to the subacute study, females showed a reduction in AST (100, 200 and 400mg/kg), ALT (200mg/kg) and BUN (100 and 200mg/kg) levels, while male rats 400mg/kg presented an increase in AST levels. The Chol dosage significantly decreased in female rats in a dose-dependent manner, whereas for male rats this parameter showed no statistically significant reductions. No behavioral and histopathological changes were recorded. Our results indicate that the hydroethanolic extract of Dolichandra unguis-cati leaves did not present relevant toxic effects when administered orally to male and female rats. The extract also showed a potential hypocholesterolemic activity.

Calil Brondani J ，Reginato FZ ，da Silva Brum E ，de Souza Vencato M ，Lima Lhamas C ，Viana C ，da Rocha MI ，de Freitas Bauermann L ，Manfron MP ... -  《-》

Acute and subacute toxicity and chemical constituents of the hydroethanolic extract of Verbena litoralis Kunth.

Verbena litoralis Kunth is a native species of South America, popularly known as gervãozinho-do-campo or erva-de-pai-caetano. It is used in gastrointestinal disorders, as detoxifying the organism, antifebrile properties and amidaglitis. To identify the chemical constituents of the hydroethanolic extract obtained from the aerial parts of V. litoralis and to evaluate the acute and sub-acute toxicity in male and female rats. The single dose (2000 mg/kg) of the extract was administered orally to male and female rats. In the subacute study the extract was given at doses of 100, 200 and 400 mg/kg during 28 days orally. Biochemical, hematological and histological analyzes were performed, oxidative stress markers were tested and chemical constituents were identified through UHPLC-ESI-HRMS RESULTS: Six classes of metabolites were identified: iridoids glycosides, flavonoids, phenylpropanoids-derived, phenylethanoid-derived, cinnamic acid-derived and triterpenes. In the acute treatment, the extract was classified as safe (category 5), according to the OECD guide. Our results demonstrated that subacute administration of the crude extract of V. litoralis at 400 mg/kg resulted in an increase in AST in males, whereas ALT enzyme showed a small increase in males that received 200 mg/kg and 400 mg/kg of the extract. The extract of the aerial parts of Verbena litoralis did not present significant toxicity when administered a single dose. However, when different doses were administered for 28 days, were observed changes in hematological, biochemical and histological parameters in rats.

de Lima R ，Guex CG ，da Silva ARH ，Lhamas CL ，Dos Santos Moreira KL ，Casoti R ，Dornelles RC ，da Rocha MIUM ，da Veiga ML ，de Freitas Bauermann L ，Manfron MP ... -  《-》

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 ... -  《-》