Di-(2-ethylhexyl) phthalate (DEHP) is a common plasticizer, which is known to be an environmental endocrine-disrupting chemical that can jeopardize the male reproductive system. Prepuberal exposure to DEHP leads to steroidogenesis disorders. However, the specific mechanism remains ambiguous. Therefore, Sprague Dawley (SD) rats underwent prepuberal DEHP exposure at a dose of 500 mg/kg per day through gavage. Additionally, the resulting testicular injury was evaluated to confirm the disturbed steroidogenesis. Changes in testicular histology, significant reduction of serum testosterone (P < 0.01) and luteinizing hormone (P < 0.001), and significantly decreased expressions of steroidogenic acute regulatory protein (P < 0.01) and 3-beta-hydroxysteroid dehydrogenase (P < 0.05) were found in DEHP-treated rats. DEHP exposure resulted in obvious intestinal damage and oxidative stress imbalance, primarily in the jejunum. Both the activation of the nuclear factor-E2-related factor 2 (Nrf2) signaling pathway and alterations of microbiota profiles were observed in all three gut specimens, but were most notable in the jejunum. We hypothesize that the gut-microbiota-testis axis, which is mediated by the activation of the Nrf2 antioxidant pathway, could be involved in the dysfunction of prepuberal steroidogenesis induced by DEHP.
Keywords: Di-(2-ethylhexyl) phthalate; Gut microbiota; Gut-microbiota-testis axis; Nrf2 signaling pathway; Oxidative stress; Prepuberal testis.