Avaliação da toxicidade in vivo e in vitro da goma do cajueiro (Anacardium Occidentale)

Abstract

Popularly known as cashew tree, Anacardium Occidentale is a Brazilian tree which is typical of tropical climate. Cashew's gum is a complex heteropolysaccharides especially extracted from the trunk of Anacardium Occidentale, being applied to several fields such as in Food and Pharmacy areas. It has shown properties which qualify it as an alternative use to Arabic gum, what indicates a potentially efficient possibility to be employed by pharmaceutical, food and cosmetic industries. The present study is relevant as there are several studies which indicate Cashew’s gum pharmacological activities and its pharmaceutical technology, however its safety profile is still unknown. In this sense, non-clinical acute toxicity studies are important in assessing the safety of products used by society. The pursued objective in this work was to start out an in vivo and in vitro evaluation of the non-clinical toxicity of cashew gum. The cashew gum was supplied by EMBRAPA and collected from plants exposed to treatment with Ethrel® (2-chloroethylphosphonic acid) (additive). In what regards to the evaluation of toxicity in vitro of cashew gum treated with Ethrel®, it was performed on isolated human neutrophils and subjected to both MTT and LDH tests. Whereas, the in vivo toxicity evaluation was made in Wistar rats, orally treated (single dose), and it was distributed in three experimental groups: Control (water 10 ml/kg), Gum without Ethrel® ( 2 g / kg); Gum with Ethrel® (2g / kg). The animals were observed for a period of 14 days, day 0 (zero) corresponds to the day before the experiment and day 15 corresponds to the last day of experiment, when the animals were euthanized. The animals were also evaluated for behavioral changes (Hippocratic test, Malone, 1962), biochemical and hematological parameters before and at the end of tests, as well as macro and microscopic analysis of the lungs, livers and kidneys were done. After statistical analysis, the weights of the organs of the gum groups without Ethrel® and gum with Ethrel® did not show any significant differences when compared to the vehicle. The Ethrel®-free gum group presented a significant difference when compared to day 0 in the ALT and creatinine values. While the Ethrel® gum group presented a significant difference when compared to day 0 in the values of ALT, urea, hemoglobin, platelet numbers and in the neutrophil differential count. Regarding the behavioral evaluation, none of the groups presented any alteration for the evaluated parameters. The organs analyzed did not show significant changes in relation to the control group. In the cytotoxicity tests, the gum did not reveal any significant cell alteration at the dosages performed, what corroborates with the results in vivo. Cashew gum was safe in the acute phase of the study. The alterations found were neither significant nor could be related to cashew gum