The effects of 17β-trenbolone and bisphenol A on sexual behavior and social dominance via the hypothalamic-pituitary-gonadal axis in male mice

Abstract

17β-Trenbolone (17-TB) is well documented as an environmental endocrine disruptor in aquatic biological studies, but its effects on mammals remain poorly understood. Furthermore, 17-TB acts as a hormone with properties similar to testosterone, and the consequences of juvenile exposure on adult social behavior remain uncertain. Bisphenol A (BPA) acts as an estrogen-like hormone, compared to 17-TB. Three-week-old male Balb/c mice were exposed orally to 17-TB (100 µg/(kg·day)) and BPA (4 mg/(kg·day)) for 28 days. Assessments of social interactions and a three-chamber test showed that 17-TB increased virility in male mice, intensified both male and female sexual behavior, and attracted and accepted female mice. It also increased social dominance through tube tests in male mice and markedly activated the c-Fos+ immune response in the medial prefrontal cortex (mPFC) and basal amygdala (BLA). ELISA data showed that 17-TB and BPA exposure significantly affected serum gonadotropin-releasing hormone (GnRH), growth hormone (GH), estradiol (E2), and luteinizing hormone (LH) levels, as well as testicular lesions and androgen receptor (ARβ) and estrogen receptor (ERα) synthesis. Testicular transcriptomic analysis further confirmed that could disrupt steroid synthesis and linoleic acid-related biometabolic processes. These findings suggest the influence of 17-TB and BPA exposure on sexual behavior and fertility in male mice, possibly through modulation of the hypothalamic-pituitary-gonadal axis. This study provides insights relevant to human reproductive health and neuro-social behavioral research, and the potential risk of environmental disturbances should not be overlooked.