title: Critical estradiol dose optimization for oocyte in vitro maturation in the common marmoset.
abstract: The aim of the present study was to critically evaluate the effect of different concentrations of estradiol (E2) during IVM of common marmoset (Callithrix jacchus) oocytes from antral follicles. The doses tested were 0, 0.1, 1, or 10 μg/mL E2 (referred to as 0 E2, 0.1 E2, 1 E2, and 10 E2 groups). After a preincubation, the concentration of E2 in IVM drops under oil was approximately 20% of the amount added (0.02; 0.2 and 1.9 μg/mL, respectively) because of absorption into the oil. Oocyte progression to metaphase II was significantly higher in the 0.1 E2 group than that in the absence of E2. With progressively higher doses, the maturation rate tended to decrease suggesting an overdose effect. Furthermore, the total first cleavage rate was significantly higher in the 0.1 E2 group than that in the 0 E2 group and decreased progressively with further increases in E2 concentration, with the 10 E2 group showing the same low rate as without E2. The oocytes which failed to cleave, after maturation in 10 E2, showed obvious signs of overdose with the highest rates of degeneration and abnormal spindle form, and an absence of embryo progression. In contrast to these obvious negative effects on the oocyte, 10 E2 was the only group in which a significant increase in radial cumulus expansion was observed. The concentration 0.1 E2, which is 10 times lower than the most commonly used E2 dose, produced the best results in all oocyte factors evaluated. These results represent the first study for a primate species showing a strong positive effect of E2 on oocyte maturation and embryo development, but only at the optimal concentration, and emphasize the critical limits of the optimal concentration range.
authors.affiliation: Reproductive Biology Unit, German Primate Center, Leibniz Institute for Primate Research, Göttingen, Germany; Department of Biology, Free University, Berlin, Germany. Electronic address: olenatkachenko@googlemail.com.
authors.forename: O Y
authors.initials: OY
authors.lastname: Tkachenko
authors.affiliation: Reproductive Biology Unit, German Primate Center, Leibniz Institute for Primate Research, Göttingen, Germany; Department of Biology, Medical University of Sofia, Sofia, Bulgaria.
authors.forename: S
authors.initials: S
authors.lastname: Delimitreva
authors.affiliation: Endocrinology Laboratory, German Primate Centre, Leibniz Institute for Primate Research, Göttingen, Germany.
authors.forename: M
authors.initials: M
authors.lastname: Heistermann
authors.affiliation: Reproductive Biology Unit, German Primate Center, Leibniz Institute for Primate Research, Göttingen, Germany; Department of Internal Medicine, Roskilde Hospital, Roskilde, Denmark.
authors.forename: J U
authors.initials: JU
authors.lastname: Scheerer-Bernhard
authors.affiliation: Reproductive Biology Unit, German Primate Center, Leibniz Institute for Primate Research, Göttingen, Germany; Department of Hepato-Gastroenterology, Nouvel Hôpital Civil, Strasbourg University Hospital, Strasbourg, France.
authors.forename: E
authors.initials: E
authors.lastname: Wedi
authors.affiliation: Reproductive Biology Unit, German Primate Center, Leibniz Institute for Primate Research, Göttingen, Germany.
authors.forename: P L
authors.initials: PL
authors.lastname: Nayudu
mesh_terms: D000818:Animals; D002144:Callithrix; D004305:Dose-Response Relationship, Drug; D046149:Embryo Culture Techniques / Q000662:veterinary; D047108:Embryonic Development / Q000187:drug effects; D004958:Estradiol / Q000008:administration & dosage*; D005260:Female; D005307:Fertilization in Vitro / Q000662:veterinary; D059471:In Vitro Oocyte Maturation Techniques / Q000379:methods / Q000662:veterinary*; D008297:Male
chemical_list: D004958:Estradiol
keywords: Cumulus expansion; Embryo; Estradiol; IVM; Marmoset monkey