Estudo dos efeitos antitumorais e toxicológicos do óleo essencial das folhas de Xylopia frutescens Aubl. (Annonaceae)

• Autor(a) principal: Lunguinho, Daiene Martins
• Data de Publicação: 2012
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: Biblioteca Digital de Teses e Dissertações da UFPB
• Texto Completo: https://repositorio.ufpb.br/jspui/handle/tede/6738
• topic: Xylopia frutescens; Óleo essencial; Atividade antitumoral; Toxicidade; Xylopia frutescens; Essential oil; Antitumor activity; Toxicity; CNPQ::CIENCIAS BIOLOGICAS::FARMACOLOGIA

Cancer is a disease of genetic material of our cells, whose initiation and progression involve steps in which the DNA accumulates a series of mutations. This disease is responsible for over 7.6 million deaths per year, representing 13% of all causes of death in the world. Many drugs currently used in chemotherapy have been isolated from plant species or derived from a natural prototype. However, antineoplastic agents, natural or synthetic, can cause serious damage to the organism, justifying the need for its toxicity. The genus Xylopia is considered one of the largest among the Annonaceae, with about 160 species, pantropical distribution. The species of this genus are known for their pharmacological activities and uses ethnomedicine. Xylopia frutescens Aubl., popularly known as "twine", "seed-to-twine" and "red-twine" is seldom reported in the literature both in aspects of phytochemical and pharmacological. Studies report that species of Xylopia and different constituents of these isolates have antitumor activity in vitro and in vivo by different mechanisms of action, a fact that arouses interest for the investigation of a possible antitumor activity of Xylopia frutescens. Additionally, essential oils isolated from different species are known to have different biological activities, among them anti-tumor activity. Given the above, this study aimed to evaluate the antitumor activity and toxicity of essential oil from leaves of X. frutescens (O.E.X.p) by means of in vitro and in vivo. Initially we evaluated the bioactivity of the oil against the brine shrimp Artemia salina. The LC50 value obtained was 180.7 mg / mL, demonstrating that this bioactive oil. The assessment of in vitro antitumor activity against sarcoma 180 cell line, the value of IC50 obtained by reduction of the MTT assay was 216.6 mg / mL. The CH50 value obtained in the experiment of cytotoxicity against erythrocytes of mice was 63.87 mg / mL, demonstrating the toxicity of the product front erythrocytes. During the acute toxicity test was no record of changes in behavior and death of the animals treated with 250 mg / kg, however at doses of 375 and 500 mg / kg these effects were observed. Based on these results, the no observed effect adverse level - NOAEL of O.E.X. was 250 mg/ kg and lowest observed effect adverse level - LOAEL was 375 mg / kg. In the evaluation of antitumor activity in vivo inhibition rates of tumor growth (sarcoma 180) was 45.1% and 65.9% for the 100 mg / kg and 150 mg / kg O.E.X. respectively. The toxicological analyzes showed hematologic, gastrointestinal (evidenced by the anorexic effect) and biochemistry toxicity, the latter demonstrated by significant changes in liver function (increased AST), and corroborated with histopathological tests, for both treated groups O.E.X. However, the changes are considered reversible and not substantial when compared to those produced by several widely used anticancer drugs in clinical medicine, including 5-FU, used with standard drug. The oil under study has not genotoxic.Therefore, it is possible to infer that O.E.X. has significant antitumor activity and moderate toxicity in experimental models evaluated, which is not a limiting factor for its possible therapeutic applicability. However, controlled studies are needed, which may help to elucidate more precisely the possible risks of their use by the population for therapeutic purposes.