Journal article
Aneuploid sperm formation in rainbow trout exposed to the environmental estrogen 17α-ethynylestradiol
Proceedings of the National Academy of Sciences - PNAS, Vol.105(50), pp.19786-19791
12/16/2008
Handle:
https://hdl.handle.net/2376/105490
PMCID: PMC2604943
PMID: 19066213
Abstract
Environmental contaminants that mimic native estrogens (i.e., environmental estrogens) are known to significantly impact a wide range of vertebrate species and have been implicated as a source for increasing human male reproductive deficiencies and diseases. Despite the widespread occurrence of environmental estrogens and recognized detrimental effects on male vertebrate reproduction, no specific mechanism has been determined indicating how reduced fertility and/or fecundity is achieved. Previous studies show that male rainbow trout,
Oncorhynchus mykiss
, exposed to the environmental estrogen 17α-ethynylestradiol (EE2) before gamete formation and fertilization produce progeny with significantly reduced embryonic survival. To determine whether this observed decrease results from sperm chromosome alterations during spermatogenesis, male rainbow trout were exposed to 10 ng of EE2/l for 50 days. After exposure, semen was collected and sperm aneuploidy levels analyzed with two chromosome markers by fluorescent
in situ
hybridization.
In vitro
fertilizations were also conducted by using control and exposed sperm crossed to eggs from an unexposed female for offspring analysis. Evaluations for nucleolar organizer region number and karyotype were performed on developing embryos to determine whether sperm aneuploidy translated into embryonic aneuploidy. Results conclusively show increased aneuploid sperm formation due to EE2 exposure. Additionally, embryonic cells from propagated progeny of individuals possessing elevated sperm aneuploidy display high levels of embryonic aneuploidy. This study concludes that EE2 exposure in sexually developing male rainbow trout increases levels of aneuploid sperm, providing a mechanism for decreased embryonic survival and ultimately diminished reproductive success in EE2 exposed males.
Metrics
9 Record Views
Details
- Title
- Aneuploid sperm formation in rainbow trout exposed to the environmental estrogen 17α-ethynylestradiol
- Creators
- Kim H Brown - Department of Biological Sciences and Center for Reproductive Biology, University of Idaho, P.O. Box 443051, Moscow, ID 83844-3051; andIrvin R Schultz - Battelle Pacific Northwest National Laboratory-Marine Science Laboratory, 1529 West Sequim Bay Road, Sequim, WA 98382J. G Cloud - Department of Biological Sciences and Center for Reproductive Biology, University of Idaho, P.O. Box 443051, Moscow, ID 83844-3051; andJames J Nagler - Department of Biological Sciences and Center for Reproductive Biology, University of Idaho, P.O. Box 443051, Moscow, ID 83844-3051; and
- Publication Details
- Proceedings of the National Academy of Sciences - PNAS, Vol.105(50), pp.19786-19791
- Academic Unit
- UNKNOWN
- Publisher
- National Academy of Sciences
- Identifiers
- 99900546840101842
- Language
- English
- Resource Type
- Journal article