Avaliação dos efeitos de extratos de erva-mate sobre o desenvolvimento embrionário inicial de galinha-doméstica

Abstract

Yerba mate (llex paraguariensis A.St.-Hil.) is a plant native to South America, used in the preparation of different traditional beverages. Its chemical composition includes polyphenols, alkaloids, saponins, vitamins and minerals. This phytochemical variability is directly related to the therapeutic benefits associated with yerba mate consumption. Among other effects, I. paraguariensis extracts have antimicrobial, antiparasitic and anti-inflammatory properties. Studies on the toxicity of the plant are scarce and show conflicting results. Few studies have analyzed the direct action of yerba mate on the embryonic development of vertebrates. Thus, the aim of this study was to evaluate whether aqueous extracts of raw and commercial yerba mate have toxic effects on animal embryonic development, using the domestic chicken as an experimental model. This model organism was chosen because of its several advantages, such as the short development time and independence from the external environment and the maternal organism to develop. Raw yerba mate was prepared with material collected from a cultivated area and processed in the laboratory, while commercial yerba mate underwent common industrial processing. The extracts were prepared with distilled water at 70°C, filtered and sterilized in an autoclave. Fertile chicken eggs were injected with approximately 100 uL of each extract (30 g/L), through the air chamber. The control group received no treatment. After three days of incubation, the eggs were opened and checked for viability. Alive embryos were euthanized and then collected and mounted on permanent slides using the whole-mount technique. Statistical analyzes were performed using the RStudio software, in R programming language. Data with binomial distribution and Poisson distribution were analyzed using the Tukey test, using the generalized linear model, and data referring to the stages of embryonic development were submitted to the Kruskal-Wallis test. No statistically significant effects were observed on the parameters of egg viability, embryonic survival and malformations occurrence. However, there were significant differences (p < 0.05) in relation to heart rate and among developmental stages of the embryos. These effects are supposed to be related to the chemical compounds present in the extracts. However, the mechanisms involved still need to be understood. It is suggested that further studies be conducted to assess the toxic potential of yerba mate at molecular, cellular and systemic levels, through more specific methods and using other experimental models.