Dataset Information

Analysis of the phospholipid profile of metaphase II mouse oocytes undergoing vitrification.

ABSTRACT: Oocyte freezing confers thermal and chemical stress upon the oolemma and various other intracellular structures due to the formation of ice crystals. The lipid profiles of oocytes and embryos are closely associated with both, the degrees of their membrane fluidity, as well as the degree of chilling and freezing injuries that may occur during cryopreservation. In spite of the importance of lipids in the process of cryopreservation, the phospholipid status in oocytes and embryos before and after freezing has not been investigated. In this study, we employed mass spectrometric analysis to examine if vitrification has an effect on the phospholipid profiles of mouse oocytes. Freshly prepared metaphase II mouse oocytes were vitrified using copper grids and stored in liquid nitrogen for 2 weeks. Fresh and vitrified-warmed oocytes were subjected to phospholipid extraction procedure. Mass spectrometric analyses revealed that multiple species of phospholipids are reduced in vitrified-warmed oocytes. LIFT analyses identified 31 underexpressed and 5 overexpressed phospholipids in vitrified mouse oocytes. The intensities of phosphatidylinositol (PI) {18?2/16?0} [M-H]- and phosphatidylglycerol (PG) {14?0/18?2} [M-H]- were decreased the most with fold changes of 30.5 and 19.1 in negative ion mode, respectively. Several sphingomyelins (SM) including SM {d38?3} [M+H]+ and SM {d34?0} [M+K]+ were decreased significantly in positive ion mode. Overall, the declining trend of multiple phospholipids demonstrates that vitrification has a marked effect on phospholipid profiles of oocytes. These results show that the identified phospholipids can be used as potential biomarkers of oocyte undergoing vitrification and will allow for the development of strategies to preserve phospholipids during oocyte cryopreservation.

SUBMITTER: Jung J

PROVIDER: S-EPMC4102530 | biostudies-literature | 2014

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Analysis of the phospholipid profile of metaphase II mouse oocytes undergoing vitrification.

Jung Jaehun J Shin Hyejin H Bang Soyoung S Mok Hyuck Jun HJ Suh Chang Suk CS Kim Kwang Pyo KP Lim Hyunjung Jade HJ

PloS one 20140717 7

Oocyte freezing confers thermal and chemical stress upon the oolemma and various other intracellular structures due to the formation of ice crystals. The lipid profiles of oocytes and embryos are closely associated with both, the degrees of their membrane fluidity, as well as the degree of chilling and freezing injuries that may occur during cryopreservation. In spite of the importance of lipids in the process of cryopreservation, the phospholipid status in oocytes and embryos before and after f ...[more]

PMID: 25033391

Similar Datasets

Project description:Objective:Over the last years, vitrification has been widely used for oocyte cryopreservation, in animals and humans; however, it frequently causes minor and major epigenetic modifications. The effect of oocyte vitrification on levels of acetylation of histone H4 at lysine 12 (AcH4K12), and histone acetyltransferase (Hat) expression, was previously assessed; however, little is known about the inhibition of Hat expression during oocyte vitrification. This study evaluated the effect of anacardic acid (AA) as a Hat inhibitor on vitrified mouse oocytes. Materials and Methods:In this experimental study, 248 mouse oocytes at metaphase II (MII) stage were divided in three experimental groups namely, fresh control oocytes (which were not affected by vitrification), frozen/thawed oocytes (vitrified) and frozen/thawed oocytes pre-treated with AA (treatment). Out of 248 oocytes, 173 oocytes were selected and from them, 84 oocytes were vitrified without AA (vitrified group) and 89 oocytes were pretreated with AA, and then vitrified (treatment group). Fresh MII mouse oocytes were used as control group. Hat expression and AcH4K12 levels were assessed by using real-time quantitative polymerase chain reaction (PCR) and immunofluoresce staining, respectively. In addition, survival rate was determined in vitrified and treatment oocytes. Results:Hat expression and AcH4K12 modification significantly increased [4.17 ± 1.27 (P≤0.001) and 97.57 ± 6.30 (P<0.001), respectively] in oocytes that were vitrified, compared to the fresh oocytes. After treatment with AA, the Hat mRNA expression and subsequently H4K12 acetylation levels were significantly reduced [0.12 ± 0.03 (P≤0.001) and 89.79 ± 3.20 (P≤0.05), respectively] in comparison to the vitrified group. However, the survival rate was not significantly different between the vitrified (90.47%) and treatment (91.01%) groups (P>0.05). Conclusion:The present study suggests that AA reduces vitrification risks caused by epigenetic modifications, but does not affect the quality of vitrification. In fact, AA as a Hat inhibitor was effective in reducing the acetylation levels of H4K12.

Project description:BackgroundAn inverse relationship between oocyte efficiency and ovarian response was reported in conventional IVF. The purpose of this study was to report metaphase II (MII) oocyte efficiency according to oocyte yield in minimal/mild stimulation IVF (mIVF) and to assess whether oocyte yield affects live birth rate (LBR).MethodsInfertile women (n = 264) aged < 39 years old with normal ovarian reserve who had mIVF were recruited. All participants received the same protocol for ovarian stimulation. All the embryos were cultured to the blastocyst stage and vitrified using a freeze-all approach. This was followed by a single blastocyst transferred to each participant in subsequent cycles over a 6-month period. Ovarian response was categorized according to the number of MII oocyte yield (low: 1-2, intermediate: 3-6 and high ≥ 7 MII oocytes). MII oocyte utilization rate was calculated as the number of live births divided by the number of MII oocytes produced after only one oocyte retrieval and subsequent transfers of vitrified/warmed blastocysts. The main outcome measure was cumulative LBR over a 6-month period.ResultsAmong all the participants, 1173 total retrieved oocytes (4.4 ± 0.2 per patient) resulted in 1019 (3.9 ± 0.2 per patient) total MII oocytes, a clinical pregnancy rate of 48.1 % and a LBR of 41.2 %. Oocyte utilization rate was inversely related to ovarian response where it was 30.3 % in the "low" vs. 9.3 % in the "intermediate" vs. 4.3 % in the "high" oocyte yield groups (p < 0.05). Implantation rate significantly dropped as the number of MII oocytes increased and was highest in the "low" oocyte yield group (p < 0.0001). Cumulative LBR was similar in "low," "intermediate," and "high" oocyte yield groups (p > 0.05). The number of MII oocytes had poor sensitivity and specificity for predicting a live birth.ConclusionThese data extend the hypothesis of oocyte efficiency reported in conventional IVF protocols to mIVF protocols.Trial registrationRegistration clinicaltrials.gov: NCT00799929.

Project description:Study question: Does storage time impact on transcriptome of slowly frozen cryopreserved human metaphase II (MII) oocytes? Summary answer: For the first time, we demonstrate that the length of cryostorage has no effect on the gene expression profile of human metaphase II oocytes. What is known already: Oocyte cryopreservation is a largely-used technique in IVF for storage of surplus oocytes, as well as for fertility preservation (i.e., women undergoing gonadotoxic therapies) and oocyte donation programs. Although it is known that cryopreservation negatively impacts on oocyte physiology and it is associated with decrease of transcripts, no experimental data about the effect of storage time on the oocyte molecular profile are available to date. Study design, size, duration: This study included 27 women undergoing IVF treatment, < 38 years aged, without any ovarian pathology. Surplus MII oocytes were donated after written informed consent. A total of 31 non-cryopreserved oocytes and 68 surviving slow-frozen/rapid-thawed oocytes (32 oocytes cryostored for 3 years and 36 cryostored for 6 years) were analyzed. Participants/materials, setting, methods: Pools of ?10 oocytes for each group were prepared. Total RNA was extracted from each pool, amplified, labeled and hybridized on 4x44K v2 microarrays (Agilent). Analyses were performed by R v3.1.3 software using the limma package v3.22.7. Main results and the role of chance: Comparison of gene expression profiles between surviving thawed oocytes after 3 and 6 years of storage in liquid nitrogen found no differently expressed genes. The expression profiles of cryopreserved MII oocytes significantly differed from those of non-cryopreserved oocytes in 107 probe sets corresponding to 73 down-regulated and 29 up-regulated unique transcripts. Gene Ontology analysis by DAVID bioinformatics resource disclosed that cryopreservation deregulates genes involved in oocyte function and early embryo development, such as chromosome organization, RNA splicing and processing, cell cycle process, response to DNA damage stimulus, cellular response to stress and DNA repair, calcium ion binding, malate dehydrogenase activity, mitochondrial membrane respiratory chain. Among the probes significantly up-regulated in cryopreserved oocytes, 2 corresponded to ovary-specific expressed large intergenic noncoding (linc)RNAs. This study included 27 women undergoing IVF treatment, < 38 years aged, without any ovarian pathology. Surplus MII oocytes were donated after written informed consent. A total of 31 non-cryopreserved oocytes and 68 surviving slow-frozen/rapid-thawed oocytes (32 oocytes cryostored for 3 years and 36 cryostored for 6 years) were analyzed.

Project description:Study question: Does storage time impact on transcriptome of slowly frozen cryopreserved human metaphase II (MII) oocytes? Summary answer: For the first time, we demonstrate that the length of cryostorage has no effect on the gene expression profile of human metaphase II oocytes. What is known already: Oocyte cryopreservation is a largely-used technique in IVF for storage of surplus oocytes, as well as for fertility preservation (i.e., women undergoing gonadotoxic therapies) and oocyte donation programs. Although it is known that cryopreservation negatively impacts on oocyte physiology and it is associated with decrease of transcripts, no experimental data about the effect of storage time on the oocyte molecular profile are available to date. Study design, size, duration: This study included 27 women undergoing IVF treatment, < 38 years aged, without any ovarian pathology. Surplus MII oocytes were donated after written informed consent. A total of 31 non-cryopreserved oocytes and 68 surviving slow-frozen/rapid-thawed oocytes (32 oocytes cryostored for 3 years and 36 cryostored for 6 years) were analyzed. Participants/materials, setting, methods: Pools of ≈10 oocytes for each group were prepared. Total RNA was extracted from each pool, amplified, labeled and hybridized on 4x44K v2 microarrays (Agilent). Analyses were performed by R v3.1.3 software using the limma package v3.22.7. Main results and the role of chance: Comparison of gene expression profiles between surviving thawed oocytes after 3 and 6 years of storage in liquid nitrogen found no differently expressed genes. The expression profiles of cryopreserved MII oocytes significantly differed from those of non-cryopreserved oocytes in 107 probe sets corresponding to 73 down-regulated and 29 up-regulated unique transcripts. Gene Ontology analysis by DAVID bioinformatics resource disclosed that cryopreservation deregulates genes involved in oocyte function and early embryo development, such as chromosome organization, RNA splicing and processing, cell cycle process, response to DNA damage stimulus, cellular response to stress and DNA repair, calcium ion binding, malate dehydrogenase activity, mitochondrial membrane respiratory chain. Among the probes significantly up-regulated in cryopreserved oocytes, 2 corresponded to ovary-specific expressed large intergenic noncoding (linc)RNAs.

Dataset Information

Analysis of the phospholipid profile of metaphase II mouse oocytes undergoing vitrification.

Publications

Analysis of the phospholipid profile of metaphase II mouse oocytes undergoing vitrification.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets