Urban fine particulate matter (PM2.5) exposure destroys blood–testis barrier (BTB) integrity through excessive ROS-mediated autophagy

AbstractContext: Blood–testis barrier (BTB), constituted by tight junctions (TJs), adherens junctions and gap junctions, is important for spermatogenesis. PM2.5 is known to impair testicular functions and reproduction. However, its effects on BTB and the underlying mechanisms remain obscure.Objective: To investigate the roles of autophagy in BTB toxicity induced by PM2.5.Materials and methods: Sprague–Dawley rats were developmentally exposed to normal saline (NS) or PM2.5 with the doses of 9 mg/kg b.w. and 24 mg/kg b.w. via intratracheal instillation for seven weeks. Success rate of mating, sperm quality, testicular morphology, expressions of BTB junction proteins and autophagy-related proteins were detected. In addition, expressions of oxidative stress markers were also analyzed.Results: Our results demonstrated that developmental PM2.5 exposure induced noticeable decreased fertility, significantly reduced sperm count, increased sperm abnormality rate and severe testicular damage in histomorphology. The ...