title: Effects of in utero exposure to nanoparticle-rich diesel exhaust on testicular function in immature male rats.
abstract: We investigated the effects of in utero exposure to nanoparticle-rich diesel exhaust (NR-DE) on reproductive function in male rats. Pregnant F344 rats were exposed to NR-DE (148.86 microg/m(3), 1.83 x 10(6)particles/cm(3), 3.40 ppm CO, 1.46 ppm NOx), filtered diesel exhaust (F-DE; 3.10 microg/m(3), 2.66 particles/cm(3), 3.30 ppm CO, 1.41 ppm NOx), or clean air (as a control) from gestation days 1 to 19 (gestation day 0=day of sperm-positivity). Male offspring were examined on postnatal day 28. The relative weights of the seminal vesicle and prostate to body weight were decreased after exposure to NR-DE or F-DE compared with controls. Serum concentrations of testosterone, progesterone, corticosterone, and follicle stimulating hormone and testicular concentrations of steroidogenic acute regulatory protein and 17beta-hydroxysteroid dehydrogenase mRNA were decreased after exposure to NR-DE or F-DE compared with control levels. In contrast, serum concentrations of immunoreative inhibin were increased after exposure to NR-DE or F-DE compared with control levels, whereas transcription of follicle stimulating hormone receptor mRNA was increased in the NR-DE exposure group only. These results suggest that prenatal exposure to NR-DE or F-DE leads to endocrine disruption after birth and suppresses testicular function in male rats. Because both the NR-DE and F-DE-exposed groups reacted to the same extent, the nanoparticles in DE did not contribute to the observed reproductive toxicity.
authors.affiliation: Environmental Nanotoxicology Section, Research Center for Environmental Risk, National Institute for Environmental Studies, 16-2 Onogawa, Tsukuba, Ibaraki, Japan. li.chunmei@nies.go.jp
authors.forename: Chunmei
authors.initials: C
authors.lastname: Li
authors.forename: Shinji
authors.initials: S
authors.lastname: Taneda
authors.forename: Kazuyoshi
authors.initials: K
authors.lastname: Taya
authors.forename: Gen
authors.initials: G
authors.lastname: Watanabe
authors.forename: Xuezheng
authors.initials: X
authors.lastname: Li
authors.forename: Yuji
authors.initials: Y
authors.lastname: Fujitani
authors.forename: Tamie
authors.initials: T
authors.lastname: Nakajima
authors.forename: Akira K
authors.initials: AK
authors.lastname: Suzuki
mesh_terms: D015067:17-Hydroxysteroid Dehydrogenases / Q000235:genetics; D000818:Animals; D001835:Body Weight / Q000187:drug effects; D005260:Female; D005333:Fetus / Q000187:drug effects*; D005640:Follicle Stimulating Hormone / Q000097:blood; D007986:Luteinizing Hormone / Q000097:blood; D008297:Male; D053758:Nanoparticles / Q000633:toxicity*; D009929:Organ Size / Q000187:drug effects; D011247:Pregnancy; D051381:Rats; D011916:Rats, Inbred F344; D013737:Testis / Q000187:drug effects* / Q000473:pathology / Q000502:physiology; D013739:Testosterone / Q000097:blood; D001335:Vehicle Emissions / Q000633:toxicity*
chemical_list: D001335:Vehicle Emissions; D013739:Testosterone; D007986:Luteinizing Hormone; D005640:Follicle Stimulating Hormone; D015067:17-Hydroxysteroid Dehydrogenases; C044256:3 (or 17)-beta-hydroxysteroid dehydrogenase