Tao Lei1, Na Guo1, Jie-Qiong Liu2, Mei-Hua Tan1, Yu-Feng Li1. 1. Department of Reproductive Medicine, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology Wuhan, China. 2. Department of Anesthesiology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology Wuhan, China.
Abstract
BACKGROUND: In the assisted reproductive technique, cryopreserving in vitro-matured oocytes is a new strategy to extend the pool of total oocytes. However, oocyte cryopreservation technique is still unsatisfied. So the assessment of cyro-damage on meiotic spindle and mitochondrial function is necessary to evaluate and refine the current protocols. MATERIAL AND METHODS: The immature oocytes were donated from women undergoing ICSI cycles. Cytoskeleton was assessed by α-tubulin and mitochondria through the fluorescent ΔΨm reporter JC-1. RESULTS: Relative inner membrane potential in MII oocytes from vIVM group sharply decreased, compared with the control (n=30) (1.397 vs. 1.019, P<0.05). 45.2% defective spindles were observed in fIVM group, compared with 48.0% in vIVM group (P>0.05). Oocytes in fIVM (35.5%, 11/31) and vIVM (40.0%, 10/25) displayed abnormal chromosome (P>0.05). CONCLUSION: In vitro maturation (IVM) has an adverse effect on the organization of spindle and chromosome, and no significantly effect on spindle and chromosome was discovered after vitrification-thaw cycle, while there was obvious damage of oocyte mitochondrial function of in vitro-matured oocyte detected after warming, which may be the reason of the low following developmental potential.
BACKGROUND: In the assisted reproductive technique, cryopreserving in vitro-matured oocytes is a new strategy to extend the pool of total oocytes. However, oocyte cryopreservation technique is still unsatisfied. So the assessment of cyro-damage on meiotic spindle and mitochondrial function is necessary to evaluate and refine the current protocols. MATERIAL AND METHODS: The immature oocytes were donated from women undergoing ICSI cycles. Cytoskeleton was assessed by α-tubulin and mitochondria through the fluorescent ΔΨm reporter JC-1. RESULTS: Relative inner membrane potential in MII oocytes from vIVM group sharply decreased, compared with the control (n=30) (1.397 vs. 1.019, P<0.05). 45.2% defective spindles were observed in fIVM group, compared with 48.0% in vIVM group (P>0.05). Oocytes in fIVM (35.5%, 11/31) and vIVM (40.0%, 10/25) displayed abnormal chromosome (P>0.05). CONCLUSION: In vitro maturation (IVM) has an adverse effect on the organization of spindle and chromosome, and no significantly effect on spindle and chromosome was discovered after vitrification-thaw cycle, while there was obvious damage of oocyte mitochondrial function of in vitro-matured oocyte detected after warming, which may be the reason of the low following developmental potential.
Entities:
Keywords:
Assisted reproduction; human oocytes; mitochondrial function; spindle; vitrification
Authors: Mehdi Mohsenzadeh; Mohammad Ali Khalili; Saeedeh Nazari; Vahid Hemayatkhah Jahromi; Azam Agharahimi; Iman Halvaei Journal: Ital J Anat Embryol Date: 2012
Authors: Joseph A Lee; Jason Barritt; Rose Marie Moschini; Richard E Slifkin; Alan B Copperman Journal: Fertil Steril Date: 2012-12-21 Impact factor: 7.329