Avaliação das toxicidades sistêmica aguda e crônica do extrato de própolis em roedores

Abstract

Propolis has been empirically used in folk medicine, and every day there are new studies on its biological activity. In Dentistry, it is desired to develop a propolis paste for intracanal medication use. Evaluate, experimentally, if the oral administration of green propolis extract is capable to promote acute or chronic toxicities in rodents. Materials and methods: To assess the acute toxicity, Swiss mice were used (n=30), weighing between 25 and 30g, separated into three groups: propolis 4,000 and 5,000, which was orally (gavage) administered a single dose (4,000 or 5,000mg/kg) of propolis extract, and control, which received water orally as well. Animals were observed daily during the period of seven days since the administration in order to identify any physiological and/or behavioral changes. To evaluate the chronic toxicity, it was used 22 male Wistar rats weighing approximately 200g each. These animals were individually separated in metabolic cages, and divided in two groups: propolis, which was orally (gavage) administered a single 1mL daily dose of 500mg/kg diluted extract; and a control group, which received only water also orally. Throughout all the 30 days trial period, the animals were weighed daily, and the amount of feed and water intake was determined. It was also evaluated the hematological profile of the animals (pre and post experiment), and plasma concentrations (post experiment) of urea, creatinine, glucose, alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase, and acid phosphatase. After necropsy, it was evaluated the weight of organs, namely: heart, lung, stomach, thymus, kidneys, adrenal glands, spleen and liver, and the last four ones were histotechnical prepared for microscopic analysis. The statistical analysis was performed by using linear mixed-effects models and t-Student test, at a significance level of 5%. There was no mortality or physiological and behavioral changes in mice that received the 4,000 and 5,000mg/kg propolis dose. In the chronic evaluation both groups showed similar results in all available parameters, as in ingesta and blood, macro or microscopic analyses. The data demonstrate absence of any toxicity by oral systemic administration of green propolis extract in rodents.