title: Spermatogenesis disruption by dioxins: Epigenetic reprograming and windows of susceptibility.
abstract: Dioxins are a group of highly persistent chemicals that are generated as by-products of industrial and natural processes. Reduction in sperm counts is among the most sensitive endpoints of dioxin toxicity. The exact mechanism by which dioxins reduce sperm counts is not known. Recent data implicate the role of epididymal factors rather than disruption of spermatogenesis. Studies reviewed here demonstrate that dioxins induce the transfer of environmental conditions to the next generation via male germline following exposures during the window of epigenetic reprogramming of primordial germ cells. Increased incidence of birth defects in offspring of male veterans exposed to dioxin containing, Agent Orange, suggest that dioxins may induce epigenomic changes in male germ cells of adults during spermatogenesis. This is supported by recent animal data that show that environmental conditions can cause epigenetic dysregulation in sperm in the context of specific windows of epigenetic reprogramming during spermatogenesis.
authors.affiliation: Department of Environmental Health Sciences, University of Massachusetts Amherst, 686 N. Pleasant St., 171 Goessmann, Amherst, MA 01003-9303, USA. Electronic address: rpilsner@umass.edu.
authors.forename: J Richard
authors.initials: JR
authors.lastname: Pilsner
authors.affiliation: Department of Environmental Health Sciences, University of Massachusetts Amherst, 686 N. Pleasant St., 171 Goessmann, Amherst, MA 01003-9303, USA. Electronic address: mmpanchenko@gmail.com.
authors.forename: Mikhail
authors.initials: M
authors.lastname: Parker
authors.affiliation: Department of Genomics and Human Genetics, Vavilov Institute of General Genetics, Russian Academy of Sciences, 3 Gubkina St., 119991 Moscow, Russia; Chapaevsk Medical Association, 3a Meditsinskaya St., 446100 Chapaevsk, Samara Region, Russia. Electronic address: olegsergeyev1@yandex.ru.
authors.forename: Oleg
authors.initials: O
authors.lastname: Sergeyev
authors.affiliation: Department of Environmental Health Sciences, University of Massachusetts Amherst, 686 N. Pleasant St., 171 Goessmann, Amherst, MA 01003-9303, USA. Electronic address: asuvorov@umass.edu.
authors.forename: Alexander
authors.initials: A
authors.lastname: Suvorov
mesh_terms: D000818:Animals; D004147:Dioxins / Q000633:toxicity*; D004785:Environmental Pollutants / Q000633:toxicity*; D044127:Epigenesis, Genetic; D006801:Humans; D013091:Spermatogenesis / Q000187:drug effects*
chemical_list: D004147:Dioxins; D004785:Environmental Pollutants
keywords: DNA methylation; Dioxin; Endocrine disruption; Epigenetic; Sperm; Spermatogenesis; TCDD; Windows of susceptibility