Gastroprotective effect of the hydroethanolic extract of geopropolis produced by Melipona subnitida (Meliponinae, Apidae) in Wistar rats

The jandaíra bee (Melipona subnitida) is a species native to northeastern Brazil that produces geopropolis, a mixture of clay and propolis, used in folk medicine. Geopropolis has traditionally been used in folk medicine because of its potential therapeutic properties, including antimicrobial, anti-inflammatory, and wound-healing effects. Recent studies have highlighted the rich composition of bioactive compounds such as flavonoids and phenolic acids, contributing to their pharmacological potential. Despite these findings, the gastroprotective properties of geopropolis and the underlying mechanisms remain underexplored and warrant further investigation. Therefore, we aimed to evaluate the gastroprotective effects of a hydroethanolic extract of geopropolis (HEG) produced by M. subnitida in Wistar rats, focusing on its antioxidant activity and the role of its bioactive compounds in preventing gastric mucosal damage. The gastroprotective potential was evaluated in Wistar rats pre-treated with HEG (250, 500, and 1 000 mg/kg, orally) for seven days and subjected to acute gastric lesions with ethanol (0.2 ml/animal, orally). One group of rats that received only distilled water served as the negative control, whereas the other group that received only ethanol served as the positive control. The stomachs were evaluated to determine the following parameters: evidence of macroscopic and histological changes, volume of mucus-containing mucin, stomach pH, and index of ulcerative lesions. Kolmogorov-Smirnov and Levene tests were performed, followed by the Tukey test, with values considered significant at P < 0.05. HEG reduced the severity of the ulcerative lesions at all doses tested. Additionally, there was no significant difference in the pH values of gastric secretions, mucus volume, and mucin content in the stomachs of animals pretreated with HEG compared to the negative control group. These results indicate that HEG has gastroprotective activity, which may be related to the presence of phenolic compounds and its high antioxidant activity.