Effect of tamoxifen treatment on global and insulin-like growth factor 2-H19 locus-specific DNA methylation in rat spermatozoa and its association with embryo loss.
OBJECTIVE
To determine the effect of tamoxifen treatment on global and insulin-like growth factor 2-H19 imprinting control region (Igf2-H19 ICR)-specific DNA methylation in rat spermatozoa and analyze its association with postimplantation loss.


METHODS
Experimental prospective study.


METHODS
Animal research and academic research facility.


METHODS
Male and female 75-day-old Holtzman rats.


METHODS
Global and Igf2-H19 ICR-specific DNA methylation was analyzed in an epididymal sperm sample in control and tamoxifen-treated rats at a dose of 0.4 mg tamoxifen/kg/day. DNA methylation status was correlated to postimplantation loss in females mated with tamoxifen-treated males.


METHODS
Global sperm DNA methylation level, methylation status of Igf2-H19 ICR in sperm, postimplantation loss.


RESULTS
Tamoxifen treatment significantly reduced methylation at Igf2-H19 ICR in epididymal sperm. However, the global methylation level was not altered. A mating experiment confirmed a significant increase in postimplantation loss upon tamoxifen treatment and showed significant correlation with methylation at Igf2-H19 ICR.


CONCLUSIONS
Reduced DNA methylation at Igf2-H19 ICR in rat spermatozoa upon tamoxifen treatment indicated a role of estrogen-associated signaling in the acquisition of paternal-specific imprints during spermatogenesis. In addition, association between DNA methylation and postimplantation loss suggests that errors in paternal imprints at Igf2-H19 ICR could affect embryo development.
Pathak
Shilpa
S
National Institute for Research in Reproductive Health, Indian Council for Medical Research, Mumbai, India.
Kedia-Mokashi
Neelam
N
Saxena
Madhurima
M
D'Souza
Ryan
R
Maitra
Anurupa
A
Parte
Priyanka
P
Gill-Sharma
Manjit
M
Balasinor
Nafisa
N
D000818:Animals; D018899:CpG Islands / Q000187:drug effects; D004247:DNA / Q000187:drug effects / Q000235:genetics; D019175:DNA Methylation / Q000187:drug effects*; D020964:Embryo Loss / Q000453:epidemiology* / Q000517:prevention & control; D005260:Female; D007335:Insulin-Like Growth Factor II / Q000235:genetics*; D008297:Male; D011247:Pregnancy; D051381:Rats; D013094:Spermatozoa / Q000187:drug effects / Q000502:physiology*; D013629:Tamoxifen / Q000494:pharmacology*
D013629:Tamoxifen; D007335:Insulin-Like Growth Factor II; D004247:DNA