RESUMO

Menthofuran is a monoterpene present in various essential oils derived from species from Mentha genus, and in Brazil, those species are widely used in treating gastrointestinal and respiratory disorders. Considering the wide pharmacological potential of monoterpenes, including their antioxidant activity, this study aimed to evaluate menthofuran-gastroprotective activity, as well as the involvement of antioxidant mechanisms in this effect. The acute toxicity was evaluated according to the fixed dose method. The antiulcerogenic activity was investigated by using experimental models of gastric ulcers induced by ethanol, indomethacin, and ischemia/reperfusion in rats. The antisecretory gastric activity, the catalase activity, and the gastric wall mucus were determined in pylorus ligated rats. Gastric wall nonprotein sulfhydryl (NPSH) group content, myeloperoxidase (MPO) activity, and malondialdehyde (MDA) content were evaluated in ethanol-induced the gastric ulcer model. Menthofuran (2 g/kg) presented low acute toxicity and showed gastroprotective activity against ethanol-, indomethacin-, and ischemia/reperfusion-induced ulcers. Moreover, menthofuran presented antisecretory activity, reduced the total acidity, and increased pH of gastric secretion. On the other hand, a decrease in mucus content of gastric wall without alteration of gastric juice volume and catalase activity was observed. Interestingly, menthofuran increased NPSH levels and reduced MDA levels and MPO activity. Gastroprotective effects of menthofuran appear to be mediated, at least in part, by the NOS pathway, endogenous prostaglandins, reduced gastric juice acidity, increased concentration of the NPSH groups, and reduced lipidic peroxidation. These findings support the menthofuran as an effective gastroprotective agent, as well as the marked participation of antioxidant mechanisms in this response.

RESUMO

Curcuma longa L., also known as turmeric, has been widely studied for its various therapeutic properties, including antineoplastic action. The ethanolic extract of the plant contains several phenolic compounds, especially curcumin. Osteosarcoma is a predominant bone tumor in dogs and humans, characterized by high metastatic potential and an unfavorable prognosis. The aim of this study was to investigate the effects of turmeric ethanol extract on canine osteosarcoma cells from established culture. The cells were cultured and treated with different curcumin concentrations (0, 10 µM, 20 µM, 50 µM, 100 µM, and 1000 µM) and exposure times (24h, 48h, and 72h). We first performed tetrazolium reduction technique (MTT) assay and calculated IC50. An immunocytochemistry assay was performed after extract treatment to verify the expression of mutated p53 and therefore study the proliferative potential of malignant cells; Bcl-2 and Ki-67 were used to assess apoptosis and the degree of malignancy, respectively. The extract enhanced the proliferation of canine osteosarcoma cells, reaching 3,819.74% at 50 µM of curcumin. The extract also significantly altered the expression of mutated p53 and Ki-67 proteins but not that of Bcl-2, suggesting that it did not induce this antiapoptotic pathway. Overall, these results are prerequisite to better understanding how natural compounds such as turmeric ethanolic extract affect cell proliferation and could be used to treat various diseases.

A Curcuma longa L., planta conhecida popularmente como açafrão, tem sido amplamente estudada por suas diversas propriedades terapêuticas, incluindo a ação antineoplásica. O extrato etanólico da planta contém diversos compostos fenólicos, com destaque para a curcumina. O osteossarcoma é um tumor ósseo predominante em cães e humanos, caracterizado por apresentar alto potencial metastático e prognóstico desfavorável. Procurou-se investigar os efeitos de diferentes concentrações de curcumina do extrato etanólico de açafrão sobre células de osteossarcoma canino de cultura estabelecida. As células foram cultivadas e submetidas ao tratamento com extrato com diferentes concentrações de curcumina (0, 10 µM, 20 µM, 50 µM, 100 µM e 1000 µM) e tempos de exposição (24h, 48h e 72h) pelo EEA. Inicialmente, foram realizados: técnica de redução do tetrazólio (MTT) e cálculo da IC50. Posteriormente, após o tratamento com o extrato, realizou-se o ensaio de imunocitoquímica para verificar a expressão de p53 mutada e estudar o potencial proliferativo das células malignas; Bcl-2, com intuito de averiguar o estímulo de via antiapoptótica; e o marcador Ki-67, que sinaliza aumento no grau de malignidade. O extrato promoveu proliferação de células de osteossarcoma canino, com incremento de até 3819,74% na concentração de 50µM de curcumina. O composto também alterou a expressão das proteínas p53 mutante e Ki-67 significativamente, mas não alterou a expressão de Bcl-2, mostrando que não induziu a via antiapoptótica mediada por esta. Estes resultados demonstram que o extrato etanólico do açafrão apresenta potencial proliferativo sobre células de osteossarcoma canino, sugerindo a necessidade de conscientização e conhecimento dos reais efeitos de determinados compostos naturais, considerados seguros ao serem utilizados como tratamento de diversas enfermidades.

Assuntos

RESUMO

The selective activity of an antineoplastic drug is related to its ability to promote cytotoxic action on tumor cells and preserve the integrity of non-neoplastic cells. Beta-lapachone is extracted from the sawdust of Ipe wood, a thick bark tree from the Ipe wood found in the Brazilian Cerrado biome. This study aimed to evaluate the cytotoxic action of beta-lapachone in an endothelial cell line. The EA.hy926 cells were seeded in two groups, G1 and G2, cultured and exposed to beta-lapachone at concentrations of 0.0, 0.01, 0.03, 0.1, 0.3, 1 and 3 & 956;M for 24 hours. G1 remained under normal cultivation conditions and G2 was subjected to oxidative stress through an ischemia and reperfusion assay, in a deoxygenated sealed chamber. The cytotoxicity assay was performed using the tetrazolium reduction method. In G1, the cytotoxicity ranged from 0.0 to 10.0%; and in G2 between 0.0 and 6.3%. No statistically significant difference was observed between the obtained values. Moreover, we found no cytotoxic action of beta-lapachone on endothelial cells, and the results point out that the drug might have preserved the cells integrity against oxidative stress under the conditions of this experiment. This promising result suggests the possibility of beta-lapachone as a chemotherapy drug with selective activity.(AU)

Assuntos

RESUMO

The selective activity of an antineoplastic drug is related to its ability to promote cytotoxic action on tumor cells and preserve the integrity of non-neoplastic cells. Beta-lapachone is extracted from the sawdust of Ipe wood, a thick bark tree from the Ipe wood found in the Brazilian Cerrado biome. This study aimed to evaluate the cytotoxic action of beta-lapachone in an endothelial cell line. The EA.hy926 cells were seeded in two groups, G1 and G2, cultured and exposed to beta-lapachone at concentrations of 0.0, 0.01, 0.03, 0.1, 0.3, 1 and 3 & 956;M for 24 hours. G1 remained under normal cultivation conditions and G2 was subjected to oxidative stress through an ischemia and reperfusion assay, in a deoxygenated sealed chamber. The cytotoxicity assay was performed using the tetrazolium reduction method. In G1, the cytotoxicity ranged from 0.0 to 10.0%; and in G2 between 0.0 and 6.3%. No statistically significant difference was observed between the obtained values. Moreover, we found no cytotoxic action of beta-lapachone on endothelial cells, and the results point out that the drug might have preserved the cell’s integrity against oxidative stress under the conditions of this experiment. This promising result suggests the possibility of beta-lapachone as a chemotherapy drug with selective activity.

Assuntos