Ethyl Extract of Blaps rynchopetera Fairmaire Ameliorates Experimental Aerobic Vaginitis by Inhibiting Autophagy Activation

To investigate the therapeutic effects of Blaps rynchopetera Fairmaire (BRF) extracts on the autophagy activation in a rat model of aerobic vaginitis (AV), forty-eight adult female SD rats of the AV model were divided into five groups according to different treatments with the cream matrix, antibiotics (clindamycin phosphate, 20 mg/g), low-concentration extracts (100 mg/g), medium-concentration extracts (200 mg/g), or high-concentration extracts (300 mg/g). Two weeks after treatment, we conducted a series of assays, including measuring the improved Donders score and pH value of vaginal secretions, H&E staining, immunohistochemical (IHC) staining, western blotting, and ELISA, for evaluating the protein expression of autophagy biomarkers Beclin1 and LC3B. In vitro, BRF ethyl extracts had the lowest minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC). After administration in AV rats, the improved Donders score, pH value, and vaginal histopathology score of vaginal secretions in the model and low-concentration groups were not statistically different from those in the normal group. In contrast, these indicators improved significantly in other treatment groups, especially in the high-concentration group. Additionally, when compared to the normal group, IHC, western blot, and ELISA revealed no statistically significant difference in the expressions of Beclin1 and LC3B in the model and low-concentration groups, but decreased to varying degrees in the clindamycin, medium-concentration, and high-concentration groups, with no correlation between Beclin1 and LC3B. Medium- and high-concentration BRF ethyl extracts effectively treated AV in rats by inhibiting excessive autophagy activation and could be applied in the clinic future.