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. 2010 May;27(5):239-46.
doi: 10.1007/s10815-010-9401-z. Epub 2010 Mar 9.

In vitro maturation, apoptotic gene expression and incidence of numerical chromosomal abnormalities following cryotop vitrification of sheep cumulus-oocyte complexes

Bita Ebrahimi  1 , Mojtaba Rezazadeh Valojerdi, Poopak Eftekhari-Yazdi, Hossein Baharvand
Affiliations

In vitro maturation, apoptotic gene expression and incidence of numerical chromosomal abnormalities following cryotop vitrification of sheep cumulus-oocyte complexes

Bita Ebrahimi et al. J Assist Reprod Genet. 2010 May.

Abstract

Purpose: The purpose of this study was to evaluate the effects of cryotop vitrification of sheep cumulus-oocyte complexes (COCs) on oocyte maturation, apoptotic gene expression and incidence of chromosomal abnormalities.

Methods: Freshly isolated (control group) and vitrified-warmed COCs (cryotop group) were matured in vitro. The expression of pro- and anti-apoptotic genes was investigated by real-time PCR. The incidence of numerical chromosomal abnormalities was evaluated by cytogenetic analysis.

Results: The mean percentage of oocytes in the cryotop and control groups that reached metaphase II was 49.25 +/- 3.01% and 51.94 +/- 2.7% respectively. The expression rates of pro- and anti-apoptotic genes were similar in both groups, whereas the incidence of numerical chromosomal abnormalities was higher in the cryotop group compared to the control group (42.5% vs. 20%, p < 0.05).

Conclusion: Although cryotop vitrification of COCs did not affect the incidence of oocyte maturation or apoptotic gene expression, significant deficiencies in the maintenance of oocyte chromosomal organization were seen.

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Figures

Fig. 1
Fig. 1
(A) Healthy oocytes before and after in vitro maturation, (B) Different nuclear stages of oocytes in the control and cryotop groups. Note: Same superscripts show significant difference. a (p value ≤ 0.0001); b (p value = 0.003)
Fig. 2
Fig. 2
Fold differences of expression of relative apoptotic genes in the cryotop and control groups. Note: Data is shown as mean±SEM
Fig. 3
Fig. 3
Normal and abnormal chromosome number in mature oocytes. (A&B) control group, (C&D) cryotop group. Original magnification: 1000×
See this image and copyright information in PMC

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References

    1. Chen SU, Lien YR, Chao KH, Ho HN, Yang YS, Lee TY. Effects of cryopreservation on meiotic spindles of oocytes and its dynamis after thawing: clinical implications in oocyte freezing- a review article. Mol Cell Endocrinol. 2003;202:101–107. - PubMed
    1. Fabbri R, Porcu E, Marsella T, Primavera MR, Rocchetta G, Ciotti PM, Magrini O, Seracchioli R, Venturoli S, Flamigni C. Technical aspects of oocyte cryopreservation. Mol Cell Endocrinol. 2000;169:39–42. doi: 10.1016/S0303-7207(00)00349-X. - DOI - PubMed
    1. Vajta G, Kuwayama M. Improving cryopreservation systems. Theriogenology. 2006;65:236–244. doi: 10.1016/j.theriogenology.2005.09.026. - DOI - PubMed
    1. Pegg DE. The role of vitrification techniques of cryopreservation in reproductive medicine. Hum Fertil. 2005;8:231–239. doi: 10.1080/14647270500054803. - DOI - PubMed
    1. Pukazhenthi BS, Comizzoli P, Travis AJ, Wildt DE. Applications of emerging to the study and conservation of threatened and endangered species. Reprod Fertil Dev. 2006;18:77–90. doi: 10.1071/RD05117. - DOI - PubMed

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