The gut-microbiota-testis axis mediated by the activation of the Nrf2 antioxidant pathway is related to prepuberal steroidogenesis disorders induced by di-(2-ethylhexyl) phthalate.

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.

Increased m6A RNA modification is related to the inhibition of the Nrf2-mediated antioxidant response in di-(2-ethylhexyl) phthalate-induced prepubertal testicular injury.

Di-(2-ethylhexyl) phthalate (DEHP) is a common environmental endocrine disrupting chemical that may induce male reproductive disorders. Exposure to DEHP at a prepubertal stage could lead to prepubertal testicular injury, but the underlying mechanisms remain unclear. In this study, we exposed Sprague-Dawley rats to 0, 250, and 500 mg DEHP per kg body weight per day at the prepuberty stage from postnatal day 22 (PND 22) to PND 35 by oral gavage. Testicular injury and oxidative stress were evaluated, and the levels of 6-methyladenosine (m6A) modification and expression of modulator genes for RNA methylation were measured in testes. Furthermore, m6A modification of the important antioxidant transcription factor Nrf2 was analyzed using methylated RNA immunoprecipitation qPCR. Our results show that DEHP worsened testicular histology, decreased testosterone concentrations, downregulated expression of spermatogenesis inducers, enhanced oxidative stress, inhibited the Nrf2-mediated antioxidant pathway, and increased apoptosis in testes. Additionally, DEHP increased global levels of m6A RNA modification and altered the expression of two important RNA methylation modulator genes, FTO and YTHDC2. Moreover, m6A modification of Nrf2 mRNA increased upon DEHP exposure. Overall, these findings link oxidative stress imbalance with epigenetic effects of DEHP toxicity and provide insight into the testicular toxicity of DEHP from the new perspective of m6A modification.

Clinical and socioeconomic factors associated with delayed orchidopexy in cryptorchid boys in China: a retrospective study of 2423 cases.

We investigated the associations of clinical and socioeconomic factors with delayed orchidopexy for cryptorchidism in China. A retrospective study was conducted on cryptorchid boys who underwent orchidopexy at Children's Hospital at Chongqing Medical University in China from January 2012 to December 2017. Of 2423 patients, 410 (16.9%) received timely repair by 18 months of age, beyond which surgery was considered delayed. Univariate analysis suggested that the laterality of cryptorchidism (P = 0.001), comorbidities including inguinal hernia/scrotal hydrocele (P < 0.001) or urinary tract disease (P = 0.016), and whether patients lived in a poverty county (P < 0.001) could influence whether orchidopexy was timely or delayed. Logistic regression analysis suggested that the following factors were associated with delayed repair: unilateral rather than bilateral cryptorchidism (odds ratio [OR] = 1.752, P < 0.001), absence of inguinal hernia or hydrocele (OR = 2.027, P = 0.019), absence of urinary tract disease (OR = 3.712, P < 0.001), and living in a poverty county (OR = 2.005, P < 0.001). The duration of postoperative hospital stay and hospital costs increased with the patient's age at the time of surgery.