A study on the estrogenic effects of Benzophenone-2 in adult ovariectomized mice

Abstract Background Benzophenone-2 (BP2) is an ultraviolet absorber extensively used in personal care products. Due to rising infertility issues and scarce scientific data on its effect on female reproductive health, this study aimed to investigate the possible estrogenic effects of BP2 in adult female mice following bilateral ovariectomy. Experimental female mice were randomly assigned to 6 groups, The Sham and OVX Control groups received subcutaneous olive oil treatment, while the other three groups were administered with BP2 subcutaneously daily at a dose of 50,100 and 200 mg/kg bw for the time frame of 7 and 21 days consecutively alongside a positive OVX Control of the 17β-estradiol group at a dose of 1 µg/kg bw for the two successive periods (7 and 21 days) too. The estrogenic activity was assessed through vaginal cornification, uterine weight, serum estrogen, progesterone, FSH and LH levels, and histopathological analysis of the uterus. Results The different concentrations of Benzophenone-2 (BP2) treated ovariectomized female mice for 7 and 21 days increased vaginal cornification (20.0 ± 1.6% and 50.6 ± 0.7% respectively at 200 mg/kg bw; P < 0.001), increased uterine weight (0.062 ± 0 g at 200 mg/kg bw; P < 0.001), and increased serum estradiol levels (17.4 ± 1.6 pg/ml at 200 mg/kg bw; P < 0.05) compared to the OVX Control group. Histopathological analysis of the uterus revealed uterine atrophy in the untreated OVX Control group. At the same time, BP2-treated mice exhibited enhanced endometrial glands, proliferative luminal epithelial cells, increased lumen size, and endometrial and myometrial response. These effects were comparable to those observed in the positive OVX Control group. Conclusion Benzophenone-2 (BP2), an ultraviolet absorber may possess an estrogenic effect in ovariectomized mice, and could induce vaginal cornification, histopathological modifications as well interference with normal hormone balance in female reproductive function.