Document Type : Original Article
Embryology Department, Royan Institute for Reproductive Biomedicine, ACECR, Tehran, Iran Anatomy Department, Medical Science Faculty, Tarbiat Modares University, Tehran, Iran
Embryology Department, Royan Institute for Reproductive Biomedicine, ACECR, Tehran, Iran
Stem Cells and Developmental Biology Department, Royan Institute for Stem Cell Biology and Technology, ACECR, Tehran, Iran Developmental Biology Department, University of Science and Culture, ACECR, Tehran, Iran
To assess embryos derived by the transfer of meiosis-II chromosomes (M-II-t) from aged mice oocytes into ooplasms from younger mice to overcome the problem of age-related decline in female fertility.
Materials and methods
The developmental capacity karyotype and ultrastructure of reconstructed oocytes derived from meiosis-II chromosome transplantation from aged mice into the ooplasms of young mice by piezo-micromanipulation were assessed.
The survival rate of enucleated young oocytes was 54% and the percent of fertilized reconstructed oocytes was 23%. The rate of embryo development to the two-cell stage after cultivation was 40%. Since 82.4% of the analyzed embryos derived from reconstructed oocytes had condensed nuclei it was not possible to analyze their chromosomal integrity. However 17.6% of analyzable reconstructed old oocyte derived embryos (old-ODEs) had normal diploid sets of chromosomes. Major structural differences were not observed between young old and M-II-t derived two-cell embryos.
Our findings suggested that ooplasms from younger mice may overcome ageassociated problems in older mice.