Background:This study investigated the effect of melatonin(MT)on cell cycle(G1/S/G2/M)of parthenogenetic zygotes developed from vitrified-warmed mouse metaphase II(MII)oocytes and elucidated the potential mechanism of...Background:This study investigated the effect of melatonin(MT)on cell cycle(G1/S/G2/M)of parthenogenetic zygotes developed from vitrified-warmed mouse metaphase II(MII)oocytes and elucidated the potential mechanism of MT action in the first cleavage of embryos.Results:After vitrification and warming,oocytes were parthenogenetically activated(PA)and in vitro cultured(IVC).Then the spindle morphology and chromosome segregation in oocytes,the maternal mRNA levels of genes including Miss,Doc1r,Setd2 and Ythdf2 in activated oocytes,pronuclear formation,the S phase duration in zygotes,mitochondrial function at G1 phase,reactive oxygen species(ROS)level at S phase,DNA damage at G2 phase,early apoptosis in 2-cell embryos,cleavage and blastocyst formation rates were evaluated.The results indicated that the vitrification/warming procedures led to following perturbations 1)spindle abnormalities and chromosome misalignment,alteration of maternal mRNAs and delay in pronucleus formation,2)decreased mitochondrial membrane potential(MMP)and lower adenosine triphosphate(ATP)levels,increased ROS production and DNA damage,G1/S and S/G2 phase transition delay,and delayed first cleavage,and 3)increased early apoptosis and lower levels of cleavage and blastocyst formation.Our results further revealed that such negative impacts of oocyte cryopreservation could be alleviated by supplementation of warming,recovery,PA and IVC media with 10^(−9) mol/L MT before the embryos moved into the 2-cell stage of development.Conclusions:MT might promote cell cycle progression via regulation of MMP,ATP,ROS and maternal mRNA levels,potentially increasing the first cleavage of parthenogenetic zygotes developed from vitrified-warmed mouse oocytes and their subsequent development.展开更多
Oocyte cryopreservation is widely used for clinical and social reasons.Previous studies have demonstrated that conventional slow-freezing cryopreservation procedures,but not storage time,can alter the gene expression ...Oocyte cryopreservation is widely used for clinical and social reasons.Previous studies have demonstrated that conventional slow-freezing cryopreservation procedures,but not storage time,can alter the gene expression profiles of frozen oocytes.Whether vitrification procedures and the related frozen storage durations have any effects on the transcriptomes of human metaphase Ⅱ oocytes remain unknown.Four women(30–32 years old)who had undergone IVF treatment were recruited for this study.RNA-Seq profiles of 3 fresh oocytes and 13 surviving vitrified-thawed oocytes(3,3,4,and 3 oocytes were cryostored for 1,2,3,and 12 months)were analyzed at a single-cell resolution.A total of 1987 genes were differentially expressed in the 13 vitrifiedthawed oocytes.However,no differentially expressed genes were found between any two groups among the 1-,2-,3-,and 12-month storage groups.Further analysis revealed that the aberrant genes in the vitrified oocytes were closely related to oogenesis and development.Our findings indicated that the effects of vitrification on the transcriptomes of mature human oocytes are induced by the procedure itself,suggesting that long-term cryostorage of human oocytes is safe.展开更多
Objective To discuss the reason why human M Ⅱ oocytes failed to fertilize after IVF and ICSI. Methods The unfertilized human MⅡ oocytes were collected 24-48 h after IVF and ICSI and stained for immunoflurescence and...Objective To discuss the reason why human M Ⅱ oocytes failed to fertilize after IVF and ICSI. Methods The unfertilized human MⅡ oocytes were collected 24-48 h after IVF and ICSI and stained for immunoflurescence and PI counterstain. The types of fertilization failure were identified under the fluorescence microscopy. Results About 55.8% oocytes in IVF were found no sperm in them, which were more than that in ICSI （9.7%） （P〈0.01）. About 14.9% oocytes in IVF and 58.1% in ICSI displayed oocyte activation failure. The difference was significant （P〈0.01）. Defects in pronuclear formation and or migration was found in a similar proportion of oocytes both after IVF （25.3%） and ICSI （32.3%）（P〉0.05）. There were 3.9% oocytes with other abnormalities were observed in IVF but none in ICSI. Conclusion The main reason of fertilization failure after IVF was no sperm penetration. However fertilization failure after ICSI was mainly associated with incomplete oocyte activation.展开更多
目的观察钙离子载体A23187联合嘌呤霉素激活胚胎的性染色体和胰岛素样生长因子-Ⅱ(insulin-like growthfactor-Ⅱ,IGF-Ⅱ)表达。方法收集体外成熟周期(in vitromaturation and intracytoplasmicsperminjection,IVM-ICSI)和卵母细胞单精...目的观察钙离子载体A23187联合嘌呤霉素激活胚胎的性染色体和胰岛素样生长因子-Ⅱ(insulin-like growthfactor-Ⅱ,IGF-Ⅱ)表达。方法收集体外成熟周期(in vitromaturation and intracytoplasmicsperminjection,IVM-ICSI)和卵母细胞单精子显微注射(intracytoplasmic sperminjection,ICSI)中受精失败的卵母细胞95枚,采用钙离子载体A23187和嘌呤霉素激活。应用荧光原位杂交技术分析来源于2PN2PB胚胎的性染色体;免疫组化检测IGF-Ⅱ的表达,并与正常胚胎、孤雌胚胎相比较。结果钙离子载体A23187联合嘌呤霉素能有效地激活ICSI后22h未受精卵母细胞,激活胚胎能发育到囊胚阶段。激活胚胎的性染色体为5枚XX,8枚XY。激活胚胎的IGF-Ⅱ表达与正常胚胎相近,明显较孤雌胚胎增强。结论钙离子载体A23187联合嘌呤霉素是一种安全、有效的激活方式,有希望成为ICSI受精失败的有效补救措施。展开更多
The number of growth factors involved in female fertility has been extensively studied, but reluctance to add essential growth factors in culture media has limited progress in optimizing embryonic growth and implantat...The number of growth factors involved in female fertility has been extensively studied, but reluctance to add essential growth factors in culture media has limited progress in optimizing embryonic growth and implantation outcomes, a situation that has ultimately led to reduced pregnancy outcomes. Insulin-like growth factor Ⅱ(IGF-Ⅱ) is the most intricately regulated of all known reproduction-related growth factors characterized to date, and is perhaps the predominant growth factor in human ovarian follicles. This review aims to concisely summarize what is known about the role of IGF-Ⅱ in follicular development, oocyte maturation, embryonic development, implantation success, placentation, fetal growth, and in reducing placental cell apoptosis, as well as present strategies that use growth factors in culture systems to improve the developmental potential of oocytes and embryos in different species. Synthesizing the present knowledge about the physiological roles of IGF-Ⅱ in follicular development, oocyte maturation, and early embryonic development should, on the one hand, deepen our overall understanding of the potential beneficial effects of growth factors in female reproduction and on the other hand support development(optimization) of improved outcomes for assisted reproductive technologies.展开更多
基金supported by the National Natural Science Foundation of China(grant no.32072735,31572398)the Natural Science Fund of Qinghai Province(2020-ZJ-902)by the China Agriculture Research System(grant no.CARS-36).
文摘Background:This study investigated the effect of melatonin(MT)on cell cycle(G1/S/G2/M)of parthenogenetic zygotes developed from vitrified-warmed mouse metaphase II(MII)oocytes and elucidated the potential mechanism of MT action in the first cleavage of embryos.Results:After vitrification and warming,oocytes were parthenogenetically activated(PA)and in vitro cultured(IVC).Then the spindle morphology and chromosome segregation in oocytes,the maternal mRNA levels of genes including Miss,Doc1r,Setd2 and Ythdf2 in activated oocytes,pronuclear formation,the S phase duration in zygotes,mitochondrial function at G1 phase,reactive oxygen species(ROS)level at S phase,DNA damage at G2 phase,early apoptosis in 2-cell embryos,cleavage and blastocyst formation rates were evaluated.The results indicated that the vitrification/warming procedures led to following perturbations 1)spindle abnormalities and chromosome misalignment,alteration of maternal mRNAs and delay in pronucleus formation,2)decreased mitochondrial membrane potential(MMP)and lower adenosine triphosphate(ATP)levels,increased ROS production and DNA damage,G1/S and S/G2 phase transition delay,and delayed first cleavage,and 3)increased early apoptosis and lower levels of cleavage and blastocyst formation.Our results further revealed that such negative impacts of oocyte cryopreservation could be alleviated by supplementation of warming,recovery,PA and IVC media with 10^(−9) mol/L MT before the embryos moved into the 2-cell stage of development.Conclusions:MT might promote cell cycle progression via regulation of MMP,ATP,ROS and maternal mRNA levels,potentially increasing the first cleavage of parthenogenetic zygotes developed from vitrified-warmed mouse oocytes and their subsequent development.
基金supported by grants from the National Key Research and Development Program(Nos.2017YFC1002000,2018YFC1004001,and 2016YFC1000600)the National Natural Science Foundation of China(Nos.81571386 and 31429004)the Capital Health Development Research Project(No.2018-2-4095).
文摘Oocyte cryopreservation is widely used for clinical and social reasons.Previous studies have demonstrated that conventional slow-freezing cryopreservation procedures,but not storage time,can alter the gene expression profiles of frozen oocytes.Whether vitrification procedures and the related frozen storage durations have any effects on the transcriptomes of human metaphase Ⅱ oocytes remain unknown.Four women(30–32 years old)who had undergone IVF treatment were recruited for this study.RNA-Seq profiles of 3 fresh oocytes and 13 surviving vitrified-thawed oocytes(3,3,4,and 3 oocytes were cryostored for 1,2,3,and 12 months)were analyzed at a single-cell resolution.A total of 1987 genes were differentially expressed in the 13 vitrifiedthawed oocytes.However,no differentially expressed genes were found between any two groups among the 1-,2-,3-,and 12-month storage groups.Further analysis revealed that the aberrant genes in the vitrified oocytes were closely related to oogenesis and development.Our findings indicated that the effects of vitrification on the transcriptomes of mature human oocytes are induced by the procedure itself,suggesting that long-term cryostorage of human oocytes is safe.
文摘Objective To discuss the reason why human M Ⅱ oocytes failed to fertilize after IVF and ICSI. Methods The unfertilized human MⅡ oocytes were collected 24-48 h after IVF and ICSI and stained for immunoflurescence and PI counterstain. The types of fertilization failure were identified under the fluorescence microscopy. Results About 55.8% oocytes in IVF were found no sperm in them, which were more than that in ICSI （9.7%） （P〈0.01）. About 14.9% oocytes in IVF and 58.1% in ICSI displayed oocyte activation failure. The difference was significant （P〈0.01）. Defects in pronuclear formation and or migration was found in a similar proportion of oocytes both after IVF （25.3%） and ICSI （32.3%）（P〉0.05）. There were 3.9% oocytes with other abnormalities were observed in IVF but none in ICSI. Conclusion The main reason of fertilization failure after IVF was no sperm penetration. However fertilization failure after ICSI was mainly associated with incomplete oocyte activation.
基金the National Key Research and Development Program of China (2017YFC1001500 and 2016YFC1000600)the Scientific Innovation Program of Shenzhen City, China, under basic research program (JCYJ20180305163835455)+1 种基金the Young Scholars Program of Shandong University (2016WLJH50)the Natural Science Foundation of Shandong Province (ZR2017MH049)。
文摘The number of growth factors involved in female fertility has been extensively studied, but reluctance to add essential growth factors in culture media has limited progress in optimizing embryonic growth and implantation outcomes, a situation that has ultimately led to reduced pregnancy outcomes. Insulin-like growth factor Ⅱ(IGF-Ⅱ) is the most intricately regulated of all known reproduction-related growth factors characterized to date, and is perhaps the predominant growth factor in human ovarian follicles. This review aims to concisely summarize what is known about the role of IGF-Ⅱ in follicular development, oocyte maturation, embryonic development, implantation success, placentation, fetal growth, and in reducing placental cell apoptosis, as well as present strategies that use growth factors in culture systems to improve the developmental potential of oocytes and embryos in different species. Synthesizing the present knowledge about the physiological roles of IGF-Ⅱ in follicular development, oocyte maturation, and early embryonic development should, on the one hand, deepen our overall understanding of the potential beneficial effects of growth factors in female reproduction and on the other hand support development(optimization) of improved outcomes for assisted reproductive technologies.
