Anti-androgenic activity of 3-methyl-4-nitrophenol in diesel exhaust particles.
In our continuing studies on nitrophenol derivatives as vasodilators in diesel exhaust particles, we have reported that nitrophenols in diesel exhaust particles possess not only vasodilatory activity but also estrogenic activity in vitro and in vivo, as well as anti-androgenic activity in vitro. Our efforts here were focused on the in vitro and in vivo anti-androgenic activity of 3-methyl-4-nitrophenol (4-nitro-m-cresol; PNMC), known a degradation product of the insecticide fenitrothion, in diesel exhaust particles. We investigated its anti-androgenic activity using an in vitro recombinant yeast screen and in vivo Hershberger assays. Recombinant yeast screen assay showed that PNMC possesses anti-androgenic activity at low concentrations. Furthermore, castrated 28-day-old immature male rats each implanted with a 5-mm-long silastic tube containing crystalline testosterone and injected with PNMC subcutaneously at doses from as low as 0.01 and 0.1 mg/kg up to 1 mg/kg for 5 consecutive days showed significantly decreased weights of the seminal vesicles, ventral prostate, and glans penis. Plasma follicle-stimulating hormone (FSH) and luteinizing hormone (LH) levels were significantly increased in the 0.1 mg/kg PNMC treatment group. Our results demonstrate that PNMC in diesel exhaust particles clearly has anti-androgenic activity both in vitro and in vivo and can therefore be considered as an endocrine-disrupting chemical.
Li
ChunMei
C
Department of Basic Veterinary Science, The United Graduate School of Veterinary Sciences, Gifu University, Gifu 501-1193, Japan.
Taneda
Shinji
S
Suzuki
Akira K
AK
Furuta
Chie
C
Watanabe
Gen
G
Taya
Kazuyoshi
K
D000393:Air Pollutants / Q000633:toxicity*; D000726:Androgen Antagonists / Q000633:toxicity*; D000818:Animals; D001681:Biological Assay; D003408:Cresols / Q000633:toxicity*; D004305:Dose-Response Relationship, Drug; D005640:Follicle Stimulating Hormone / Q000097:blood; D017930:Genes, Reporter; D005837:Genitalia, Male / Q000187:drug effects*; D007763:Lac Operon; D007986:Luteinizing Hormone / Q000097:blood; D008297:Male; D009919:Orchiectomy; D009929:Organ Size / Q000187:drug effects; D011401:Promoter Regions, Genetic / Q000187:drug effects; D011863:Radioimmunoassay; D051381:Rats; D017208:Rats, Wistar; D011944:Receptors, Androgen / Q000235:genetics; D012441:Saccharomyces cerevisiae / Q000378:metabolism; D013739:Testosterone / Q000097:blood; D001335:Vehicle Emissions / Q000633:toxicity*
C410798:AR protein, human; D000393:Air Pollutants; D000726:Androgen Antagonists; D003408:Cresols; D011944:Receptors, Androgen; D001335:Vehicle Emissions; C008636:4-nitro-3-cresol; D013739:Testosterone; D007986:Luteinizing Hormone; D005640:Follicle Stimulating Hormone