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Varghese J, Link B, Wong B, Thundathil JC. Comparison of the developmental competence of in vitro-produced mouse embryos cultured under 5 versus 2% O 2 with in vivo-derived blastocysts. J Assist Reprod Genet 2024:10.1007/s10815-024-03267-7. [PMID: 39313714 DOI: 10.1007/s10815-024-03267-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2023] [Accepted: 09/16/2024] [Indexed: 09/25/2024] Open
Abstract
PURPOSE The prevalence of infertility in Canada has substantially increased over 30 years, and plateaued success rates of culture systems warrant further optimization for transfer outcomes. In clinical programs, embryos commonly undergo extended culture under 5% O2 until the blastocyst stage. The aim of this study is to characterize the developmental competence and stress-related responses of embryos cultured under 5 versus 2% O2 in comparison to in vivo-derived blastocysts. We hypothesized 2% O2 compromises developmental competence through altered embryonic stress responses and induction of apoptosis-related genes relative to those cultured under 5% O2 and in vivo-derived blastocysts. METHODS Quantitative measures of development and relative expressions of a cohort of stress-related genes in CD1 mouse zygotes cultured to blastocysts under 5 or 2% O2 were compared to in vivo-derived embryos. Apoptotic responses were evaluated using an immunofluorescence assay for Caspase-3. RESULTS The mean percentage of blastocysts developed, and total cell number of embryos derived in vivo or cultured under 5% O2 was significantly higher than those cultured under 2% O2. Blastocyst expansion was greatest in embryos cultured under 5% O2. Stress response genes were significantly upregulated in embryos cultured under 2% O2, and expression of antioxidant-related genes was significantly lower in cultured versus in vivo-derived embryos. Caspase-3 immunofluorescence was significantly higher in cultured embryos versus in vivo-derived embryos. CONCLUSION We inferred that 5% O2 systems better approximate physiologic oxygen availability for culture of mouse embryos, warranting re-evaluation of culturing embryos under threshold or sub-physiologic oxygen concentrations during clinical IVF programs.
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Affiliation(s)
- Jacob Varghese
- Faculty of Veterinary Medicine, University of Calgary, Calgary, AB, T2N 4N1, Canada
| | - Brad Link
- Regional Fertility Program, 2000 Veterans Pl NW #400, Calgary, AB, T3B 4N2, Canada
| | - Ben Wong
- Regional Fertility Program, 2000 Veterans Pl NW #400, Calgary, AB, T3B 4N2, Canada
| | - Jacob C Thundathil
- Faculty of Veterinary Medicine, University of Calgary, Calgary, AB, T2N 4N1, Canada.
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Sakkas D, Navarro-Sánchez L, Ardestani G, Barroso G, Bisioli C, Boynukalin K, Cimadomo D, Frantz N, Kopcow L, Andrade GM, Ozturk B, Rienzi L, Weiser A, Valbuena D, Simón C, Rubio C. The impact of implementing a non-invasive preimplantation genetic testing for aneuploidies (niPGT-A) embryo culture protocol on embryo viability and clinical outcomes. Hum Reprod 2024; 39:1952-1959. [PMID: 39059790 DOI: 10.1093/humrep/deae156] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2024] [Revised: 06/10/2024] [Indexed: 07/28/2024] Open
Abstract
STUDY QUESTION Are modifications in the embryo culture protocol needed to perform non-invasive preimplantation genetic testing for aneuploidies (niPGT-A) affecting clinical reproductive outcomes, including blastocyst development and pregnancy outcomes? SUMMARY ANSWER The implementation of an embryo culture protocol to accommodate niPGT-A has no impact on blastocyst viability or pregnancy outcomes. WHAT IS KNOWN ALREADY The recent identification of embryo cell-free (cf) DNA in spent blastocyst media has created the possibility of simplifying PGT-A. Concerns, however, have arisen at two levels. First, the representativeness of that cfDNA to the real ploidy status of the embryo. Second, the logistical changes that need to be implemented by the IVF laboratory when performing niPGT-A and their effect on reproductive outcomes. Concordance rates of niPGT-A to invasive PGT-A have gradually improved; however, the impact of culture protocol changes is not as well understood. STUDY DESIGN, SIZE, DURATION As part of a trial examining concordance rates of niPGT-A versus invasive PGT-A, the IVF clinics implemented a specific niPGT-A embryo culture protocol. Briefly, this involved initial culture of fertilized oocytes following each laboratory standard routine up to Day 4. On Day 4, embryos were washed and cultured individually in 10 μl of fresh media. On Day 6 or 7, blastocysts were then biopsied, vitrified, and media collected for the niPGT-A analysis. Six IVF clinics from the previously mentioned trial were enrolled in this analysis. In the concordance trial, Clinic A cultured all embryos (97 cycles and 355 embryos) up to Day 6 or 7, whereas in the remaining clinics (B-F) (379 cycles), nearly a quarter of all the blastocysts (231/985: 23.5%) were biopsied on Day 5, with the remaining blastocysts following the niPGT-A protocol (754/985: 76.5%). During the same period (April 2018-December 2020), the IVF clinics also performed standard invasive PGT-A, which involved culture of embryos up to Days 5, 6, or 7 when blastocysts were biopsied and vitrified. PARTICIPANTS/MATERIALS, SETTING, METHODS In total, 428 (476 cycles) patients were in the niPGT-A study group. Embryos from 1392 patients underwent the standard PGT-A culture protocol and formed the control group. Clinical information was obtained and analyzed from all the patients. Statistical comparisons were performed between the study and the control groups according to the day of biopsy. MAIN RESULTS AND THE ROLE OF CHANCE The mean age, number of oocytes, fertilization rates, and number of blastocysts biopsied were not significantly different for the study and the control group. Regarding the overall pregnancy outcomes, no significant effect was observed on clinical pregnancy rate, miscarriage rate, or ongoing pregnancy rate (≥12 weeks) in the study group compared to the control group when stratified by day of biopsy. LIMITATIONS, REASONS FOR CAUTION The limitations are intrinsic to the retrospective nature of the study, and to the fact that the study was conducted in invasive PGT-A patients and not specifically using niPGT-A cases. WIDER IMPLICATIONS OF THE FINDINGS This study shows that modifying current IVF laboratory protocols to adopt niPGT-A has no impact on the number of blastocysts available for transfer and overall clinical outcomes of transferred embryos. Whether removal of the invasive biopsy step leads to further improvements in pregnancy rates awaits further studies. STUDY FUNDING/COMPETING INTEREST(S) This study was funded by Igenomix. C.R., L.N.-S., and D.V. are employees of Igenomix. D.S. was on the Scientific Advisory Board of Igenomix during the study. TRIAL REGISTRATION NUMBER ClinicalTrials.gov (NCT03520933).
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Affiliation(s)
- Denny Sakkas
- Boston IVF R&D Department, Boston IVF-IVIRMA Global Research Alliance, Waltham, MA, USA
| | | | - Goli Ardestani
- Boston IVF R&D Department, Boston IVF-IVIRMA Global Research Alliance, Waltham, MA, USA
| | - Gerardo Barroso
- IVF Clinical Department, Escuela Superior de Medicina Instituto Politécnico Nacional y Centro de Reproducción Arcos S.C. NASCERE, CDMX, Mexico
| | - Claudio Bisioli
- Department of Reproductive Genetics, Pregna Medicina Reproductiva, Buenos Aires, Argentina
| | | | - Danilo Cimadomo
- Science & Research, GENERA Center for Reproductive Medicine, Clinica Valle Giulia, Rome, Italy
| | - Nilo Frantz
- Embryology Department, Nilo Frantz Reproductive Medicine, Porto Alegre, Brazil
| | - Laura Kopcow
- Department of Reproductive Genetics, Pregna Medicina Reproductiva, Buenos Aires, Argentina
| | | | - Bilgen Ozturk
- Clinical Department, Bahçeci Fertility, Istanbul, Turkey
| | - Laura Rienzi
- Science & Research, GENERA Center for Reproductive Medicine, Clinica Valle Giulia, Rome, Italy
| | - Ariane Weiser
- IVF Clinical Department, Escuela Superior de Medicina Instituto Politécnico Nacional y Centro de Reproducción Arcos S.C. NASCERE, CDMX, Mexico
| | | | - Carlos Simón
- Department of Pediatrics, Obstetrics and Gynecology, University of Valencia, INCLIVA, Valencia, Spain
- Research & Medical Department, Carlos Simon Foundation, INCLIVA Health Research Institute, Valencia, Spain
- Department of Obstetrics and Gynecology, BIDMC, Harvard University, Boston, MA, USA
| | - Carmen Rubio
- R&D Department, Igenomix, Paterna, Valencia, Spain
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Wang XY, Gao Y, Liu HR, Wang T, Feng ML, Xue FR, Ding K, Yang Q, Jiang ZY, Sun D, Song CR, Zhang XJ, Liang CG. C-Phycocyanin improves the quality of goat oocytes after in vitro maturation and vitrification. Theriogenology 2024; 222:66-79. [PMID: 38626583 DOI: 10.1016/j.theriogenology.2024.04.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2024] [Revised: 03/30/2024] [Accepted: 04/11/2024] [Indexed: 04/18/2024]
Abstract
In vitro maturation (IVM) and cryopreservation of goat oocytes are important for establishing a valuable genetic bank for domesticated female animals and improving livestock reproductive efficiency. C-Phycocyanin (PC) is a Spirulina extract with antioxidant, antiinflammatory, and radical scavenging properties. However, whether PC has positive effect on goat oocytes IVM or developmental competence after vitrification is still unknown. In this study, we found that first polar body extrusion (n = 293), cumulus expansion index (n = 269), and parthenogenetic blastocyst formation (n = 281) were facilitated by adding 30 μg/mL PC to the oocyte maturation medium when compared with the control groups and that supplemented with 3, 10, 100 or 300 μg/mL PC (P < 0.05). Although PC supplementation did not affect spindle formation or chromosome alignment (n = 115), it facilitated or improved cortical granules migration (n = 46, P < 0.05), mitochondria distribution (n = 39, P < 0.05), and mitochondrial membrane potential (n = 46, P < 10-4). Meanwhile, supplementation with 30 μg/mL PC in the maturation medium could significantly inhibit the reactive oxygen species accumulation (n = 65, P < 10-4), and cell apoptosis (n = 42, P < 0.05). In addition, PC increased the oocyte mRNA levels of GPX4 (P < 0.01), and decreased the mRNA and protein levels of BAX (P < 0.01). Next, we investigated the effect of PC supplementation in the vitrification solution on oocyte cryopreservation. When compared with the those equilibrate in the vitrification solution without PC, recovered oocytes in the 30 μg/mL PC group showed higher ratios of normal morphology (n = 85, P < 0.05), survival (n = 85, P < 0.05), first polar body extrusion (n = 62, P < 0.05), and parthenogenetic blastocyst formation (n = 107, P < 0.05). Meanwhile, PC supplementation of the vitrification solution increased oocyte mitochondrial membrane potential (n = 53, P < 0.05), decreased the reactive oxygen species accumulation (n = 73, P < 0.05), promoted mitochondria distribution (n = 58, P < 0.05), and inhibited apoptosis (n = 46, P < 10-3). Collectively, our findings suggest that PC improves goat oocyte IVM and vitrification by reducing oxidative stress and early apoptosis, which providing a novel strategy for livestock gamete preservation and utilization.
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Affiliation(s)
- Xing-Yue Wang
- State Key Laboratory of Reproductive Regulation & Breeding of Grassland Livestock, School of Life Sciences, Inner Mongolia University, Hohhot, Inner Mongolia, PR China
| | - Yang Gao
- State Key Laboratory of Reproductive Regulation & Breeding of Grassland Livestock, School of Life Sciences, Inner Mongolia University, Hohhot, Inner Mongolia, PR China
| | - Hao-Ran Liu
- State Key Laboratory of Reproductive Regulation & Breeding of Grassland Livestock, School of Life Sciences, Inner Mongolia University, Hohhot, Inner Mongolia, PR China
| | - Teng Wang
- State Key Laboratory of Reproductive Regulation & Breeding of Grassland Livestock, School of Life Sciences, Inner Mongolia University, Hohhot, Inner Mongolia, PR China
| | - Meng-Lei Feng
- State Key Laboratory of Reproductive Regulation & Breeding of Grassland Livestock, School of Life Sciences, Inner Mongolia University, Hohhot, Inner Mongolia, PR China
| | - Fang-Rui Xue
- State Key Laboratory of Reproductive Regulation & Breeding of Grassland Livestock, School of Life Sciences, Inner Mongolia University, Hohhot, Inner Mongolia, PR China
| | - Kang Ding
- State Key Laboratory of Reproductive Regulation & Breeding of Grassland Livestock, School of Life Sciences, Inner Mongolia University, Hohhot, Inner Mongolia, PR China
| | - Qi Yang
- State Key Laboratory of Reproductive Regulation & Breeding of Grassland Livestock, School of Life Sciences, Inner Mongolia University, Hohhot, Inner Mongolia, PR China
| | - Zhao-Yu Jiang
- State Key Laboratory of Reproductive Regulation & Breeding of Grassland Livestock, School of Life Sciences, Inner Mongolia University, Hohhot, Inner Mongolia, PR China
| | - Dui Sun
- State Key Laboratory of Reproductive Regulation & Breeding of Grassland Livestock, School of Life Sciences, Inner Mongolia University, Hohhot, Inner Mongolia, PR China
| | - Chun-Ru Song
- State Key Laboratory of Reproductive Regulation & Breeding of Grassland Livestock, School of Life Sciences, Inner Mongolia University, Hohhot, Inner Mongolia, PR China
| | - Xiao-Jie Zhang
- State Key Laboratory of Reproductive Regulation & Breeding of Grassland Livestock, School of Life Sciences, Inner Mongolia University, Hohhot, Inner Mongolia, PR China
| | - Cheng-Guang Liang
- State Key Laboratory of Reproductive Regulation & Breeding of Grassland Livestock, School of Life Sciences, Inner Mongolia University, Hohhot, Inner Mongolia, PR China.
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Deaville LA, Berrens RV. Technology to the rescue: how to uncover the role of transposable elements in preimplantation development. Biochem Soc Trans 2024; 52:1349-1362. [PMID: 38752836 PMCID: PMC11346443 DOI: 10.1042/bst20231262] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2024] [Revised: 04/23/2024] [Accepted: 04/24/2024] [Indexed: 06/27/2024]
Abstract
Transposable elements (TEs) are highly expressed in preimplantation development. Preimplantation development is the phase when the cells of the early embryo undergo the first cell fate choice and change from being totipotent to pluripotent. A range of studies have advanced our understanding of TEs in preimplantation, as well as their epigenetic regulation and functional roles. However, many questions remain about the implications of TE expression during early development. Challenges originate first due to the abundance of TEs in the genome, and second because of the limited cell numbers in preimplantation. Here we review the most recent technological advancements promising to shed light onto the role of TEs in preimplantation development. We explore novel avenues to identify genomic TE insertions and improve our understanding of the regulatory mechanisms and roles of TEs and their RNA and protein products during early development.
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Affiliation(s)
- Lauryn A. Deaville
- Institute for Developmental and Regenerative Medicine, Oxford University, IMS-Tetsuya Nakamura Building, Old Road Campus, Roosevelt Dr, Oxford OX3 7TY, U.K
- Department of Paediatrics, Oxford University, Level 2, Children's Hospital, John Radcliffe Headington, Oxford OX3 9DU, U.K
- MRC Weatherall Institute of Molecular Medicine, Oxford University, John Radcliffe Hospital, Oxford OX3 9DS, U.K
| | - Rebecca V. Berrens
- Institute for Developmental and Regenerative Medicine, Oxford University, IMS-Tetsuya Nakamura Building, Old Road Campus, Roosevelt Dr, Oxford OX3 7TY, U.K
- Department of Paediatrics, Oxford University, Level 2, Children's Hospital, John Radcliffe Headington, Oxford OX3 9DU, U.K
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5
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Gualtieri R, De Gregorio V, Candela A, Travaglione A, Genovese V, Barbato V, Talevi R. In Vitro Culture of Mammalian Embryos: Is There Room for Improvement? Cells 2024; 13:996. [PMID: 38920627 PMCID: PMC11202082 DOI: 10.3390/cells13120996] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2024] [Revised: 06/03/2024] [Accepted: 06/05/2024] [Indexed: 06/27/2024] Open
Abstract
Preimplantation embryo culture, pivotal in assisted reproductive technology (ART), has lagged in innovation compared to embryo selection advancements. This review examines the persisting gap between in vivo and in vitro embryo development, emphasizing the need for improved culture conditions. While in humans this gap is hardly estimated, animal models, particularly bovines, reveal clear disparities in developmental competence, cryotolerance, pregnancy and live birth rates between in vitro-produced (IVP) and in vivo-derived (IVD) embryos. Molecular analyses unveil distinct differences in morphology, metabolism, and genomic stability, underscoring the need for refining culture conditions for better ART outcomes. To this end, a deeper comprehension of oviduct physiology and embryo transport is crucial for grasping embryo-maternal interactions' mechanisms. Research on autocrine and paracrine factors, and extracellular vesicles in embryo-maternal tract interactions, elucidates vital communication networks for successful implantation and pregnancy. In vitro, confinement, and embryo density are key factors to boost embryo development. Advanced dynamic culture systems mimicking fluid mechanical stimulation in the oviduct, through vibration, tilting, and microfluidic methods, and the use of innovative softer substrates, hold promise for optimizing in vitro embryo development.
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Affiliation(s)
- Roberto Gualtieri
- Department of Biology, University of Naples ‘’Federico II’’, Complesso Universitario Di Monte S. Angelo, Via Cinthia, 80126 Naples, Italy; (V.D.G.); (A.C.); (A.T.); (V.G.); (V.B.); (R.T.)
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6
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Travaglione A, Candela A, De Gregorio V, Genovese V, Cimmino M, Barbato V, Talevi R, Gualtieri R. Individually Cultured Bovine Zygotes Successfully Develop to the Blastocyst Stage in an Extremely Confined Environment. Cells 2024; 13:868. [PMID: 38786090 PMCID: PMC11119105 DOI: 10.3390/cells13100868] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2024] [Revised: 05/16/2024] [Accepted: 05/17/2024] [Indexed: 05/25/2024] Open
Abstract
The possibility of detecting the developmental competence of individually cultured embryos through analysis of spent media is a major current trend in an ART setting. However, individual embryo culture is detrimental compared with high-density group culture due to the reduced concentration of putative embryotropins. The main aim of this study was to identify an individual culture system that is not detrimental over high-density group culture in the bovine model. Blastocyst rates and competence were investigated in a conventional (GC) group, semi-confined group (MG), and individual culture (MS) in a commercial microwell device. Main findings showed that: (1) individual embryos can be continuously cultured for 7 days in ~70 nL microwells (MS) without detrimental effects compared with the GC and MG; (2) MS and MG blastocysts had a reduced number of TUNEL-positive cells compared to GC blastocysts; (3) though blastocyst mean cell numbers, mitochondrial activity, and lipid content were not different among the three culture conditions, MS blastocysts had a higher frequency of small-sized lipid droplets and a reduced mean droplet diameter compared with GC and MG blastocysts. Overall, findings open the way to optimize the development and competence of single embryos in an ART setting.
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Affiliation(s)
| | | | | | | | | | | | | | - Roberto Gualtieri
- Department of Biology, University of Naples “Federico II”, Complesso Universitario Di Monte S. Angelo, Via Cinthia, 80126 Naples, Italy; (A.T.); (A.C.); (V.D.G.); (V.G.); (M.C.); (V.B.); (R.T.)
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7
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Gardner DK, Sakkas D. Making and selecting the best embryo in the laboratory. Fertil Steril 2023; 120:457-466. [PMID: 36521518 DOI: 10.1016/j.fertnstert.2022.11.007] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2022] [Revised: 10/20/2022] [Accepted: 11/07/2022] [Indexed: 12/15/2022]
Abstract
Over the past 4 decades our ability to maintain a viable human embryo in vitro has improved dramatically, leading to higher implantation rates. This has led to a notable shift to single blastocyst transfer and the ensuing elimination of high order multiple gestations. Future improvements to embryo culture systems will not only come from new improved innovative media formulations (such as the inclusion of antioxidants), but plausibly by moving away from static culture to more dynamic perfusion-based systems now made a reality owing to the breakthroughs in three-dimensional printing technology and micro fabrication. Such an approach has already made it feasible to create high resolution devices for intracytoplasmic sperm injection, culture, and cryopreservation, paving the way not only for improvements in outcomes but also automation of assisted reproductive technology. Although improvements in culture systems can lead to further increases in pregnancy outcomes, the ability to quantitate biomarkers of embryo health and viability will reduce time to pregnancy and decrease pregnancy loss. Currently artificial intelligence is being used to assess embryo development through image analysis, but we predict its power will be realized through the creation of selection algorithms based on the integration of information related to metabolic functions, cell-free DNA, and morphokinetics, thereby using vast amounts of different data types obtained for each embryo to predict outcomes. All of this will not only make assisted reproductive technology more effective, but it will also make it more cost effective, thereby increasing patient access to infertility treatment worldwide.
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Affiliation(s)
- David K Gardner
- Melbourne IVF, East Melbourne, Victoria, Australia; School of BioSciences, University of Melbourne, Melbourne, Victoria, Australia.
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8
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Anisimova MV, Gon Y, Kontsevaya GV, Romashchenko AV, Khotskin NV, Stanova AK, Gerlinskaya LA, Moshkin MP. Body composition as an indicator of metabolic changes in mice obtained by in vitro fertilization. Vavilovskii Zhurnal Genet Selektsii 2023; 27:357-365. [PMID: 37465196 PMCID: PMC10350860 DOI: 10.18699/vjgb-23-43] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2023] [Revised: 06/05/2023] [Accepted: 06/09/2023] [Indexed: 07/20/2023] Open
Abstract
To identify body systems subject to epigenetic transformation during in vitro fertilization (IVF), comparative morphological and functional studies were performed on sexually mature offspring of outbred CD1 mice, specific-pathogen-free (SPF), obtained by IVF (experiment) and natural conception (control). The studies included assessment of age-related changes in body weight and composition, energy intake and expenditure, and glucose homeostasis. To level the effects caused by the different number of newborns in the control and in the experiment, the size of the fed litters was halved in the control females. Males obtained using the IVF procedure were superior in body weight compared to control males in all age groups. As was shown by analysis of variance with experiment/control factors, gender, age (7, 10 and 20 weeks), the IVF procedure had a statistically significant and unidirectional effect on body composition. At the same time, IVF offspring outperformed control individuals in relative fat content, but were behind in terms of lean mass. The effect of the interaction of factors was not statistically significant. IVF offspring of both sexes had higher fat to lean mass ratios (FLR). Since adipose tissue contributes significantly less to total energy intake compared to muscle, the main component of lean mass, it is not surprising that at the same level of IVF locomotor activity offspring consumed less food than controls. When converted to one gram of body weight, this difference reached 19 %. One of the consequences of reduced utilization of IVF energy substrates by offspring is a decrease in their tolerance to glucose loading. The integral criterion for the effectiveness of restoring the initial glucose level is the area under the curve (AUC), the value of which was 2.5 (males) and 3.2 (females) times higher in IVF offspring compared to the corresponding control. Thus, the totality of our original and literature data shows an increase in the risk of metabolic disorders in IVF offspring, which is confirmed by epidemiological studies of a relatively young cohort of people born using assisted reproductive technologies.
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Affiliation(s)
- M V Anisimova
- Institute of Cytology and Genetics of the Siberian Branch of the Russian Academy of Sciences, Novosibirsk, Russia
| | - Yanli Gon
- Institute of Cytology and Genetics of the Siberian Branch of the Russian Academy of Sciences, Novosibirsk, Russia
| | - G V Kontsevaya
- Institute of Cytology and Genetics of the Siberian Branch of the Russian Academy of Sciences, Novosibirsk, Russia
| | - A V Romashchenko
- Institute of Cytology and Genetics of the Siberian Branch of the Russian Academy of Sciences, Novosibirsk, Russia
| | - N V Khotskin
- Institute of Cytology and Genetics of the Siberian Branch of the Russian Academy of Sciences, Novosibirsk, Russia
| | - A K Stanova
- Institute of Cytology and Genetics of the Siberian Branch of the Russian Academy of Sciences, Novosibirsk, Russia
| | - L A Gerlinskaya
- Institute of Cytology and Genetics of the Siberian Branch of the Russian Academy of Sciences, Novosibirsk, Russia
| | - M P Moshkin
- Institute of Cytology and Genetics of the Siberian Branch of the Russian Academy of Sciences, Novosibirsk, Russia Tomsk State University, Department of Vertebrate Zoology and Ecology, Tomsk, Russia
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Suebthawinkul C, Babayev E, Lee HC, Duncan FE. Morphokinetic parameters of mouse oocyte meiotic maturation and cumulus expansion are not affected by reproductive age or ploidy status. J Assist Reprod Genet 2023; 40:1197-1213. [PMID: 37012451 PMCID: PMC10239409 DOI: 10.1007/s10815-023-02779-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2022] [Accepted: 03/17/2023] [Indexed: 04/05/2023] Open
Abstract
INTRODUCTION Morphokinetic analysis using a closed time-lapse monitoring system (EmbryoScope + ™) provides quantitative metrics of meiotic progression and cumulus expansion. The goal of this study was to use a physiologic aging mouse model, in which egg aneuploidy levels increase, to determine whether there are age-dependent differences in morphokinetic parameters of oocyte maturation. METHODS Denuded oocytes and intact cumulus-oocyte complexes (COCs) were isolated from reproductively young and old mice and in vitro matured in the EmbryoScope + ™. Morphokinetic parameters of meiotic progression and cumulus expansion were evaluated, compared between reproductively young and old mice, and correlated with egg ploidy status. RESULTS Oocytes from reproductively old mice were smaller than young counterparts in terms of GV area (446.42 ± 4.15 vs. 416.79 ± 5.24 µm2, p < 0.0001) and oocyte area (4195.71 ± 33.10 vs. 4081.62 ± 41.04 µm2, p < 0.05). In addition, the aneuploidy incidence was higher in eggs with advanced reproductive age (24-27% vs. 8-9%, p < 0.05). There were no differences in the morphokinetic parameters of oocyte maturation between oocytes from reproductively young and old mice with respect to time to germinal vesicle breakdown (GVBD) (1.03 ± 0.03 vs. 1.01 ± 0.04 h), polar body extrusion (PBE) (8.56 ± 0.11 vs. 8.52 ± 0.15 h), duration of meiosis I (7.58 ± 0.10 vs. 7.48 ± 0.11 h), and kinetics of cumulus expansion (0.093 ± 0.002 vs. 0.089 ± 0.003 µm/min). All morphokinetic parameters of oocyte maturation were similar between euploid and aneuploid eggs irrespective of age. CONCLUSION There is no association between age or ploidy and the morphokinetics of mouse oocyte in vitro maturation (IVM). Future studies are needed to evaluate whether there is an association between morphokinetic dynamics of mouse IVM and embryo developmental competence.
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Affiliation(s)
- Chanakarn Suebthawinkul
- Department of Obstetrics and Gynecology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
- Department of Obstetrics and Gynecology, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand
| | - Elnur Babayev
- Department of Obstetrics and Gynecology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | - Hoi Chang Lee
- Department of Obstetrics and Gynecology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | - Francesca E Duncan
- Department of Obstetrics and Gynecology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA.
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10
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Zhu L, Zeng X, Liu W, Han W, Huang G, Li J. Comparison of DNA methylation profiles of human embryos cultured in either uninterrupted or interrupted incubators. J Assist Reprod Genet 2023; 40:113-123. [PMID: 36459262 PMCID: PMC9840733 DOI: 10.1007/s10815-022-02669-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2022] [Accepted: 11/21/2022] [Indexed: 12/04/2022] Open
Abstract
PURPOSE We aimed to compare the DNA methylation profiles of human embryos cultured in uninterrupted or interrupted incubators. METHODS This study included 9 women, ≤ 30 years old (range: 20-30 years), without a history of genetic diseases or smoking, undergoing ICSI treatment, and each woman donated one oocyte. Embryos were randomly assigned to culture in either time-lapse imaging or standard incubators after ICSI. We compared the DNA methylation profiles of human eight-cell embryos cultured in uninterrupted condition using time-lapse imaging (TLI) incubator (EmbryoScope) to those cultured in interrupted culture model using standard incubators (SI, G185 K-System). Nine single-cell whole-genome bisulfite sequencing (WGBS) datasets were analyzed, including four SI-cultured embryos and five TLI-cultured embryos at the eight-cell stage. RESULTS A total of 581,140,020 and 732,348,182 clean reads were generated from the TLI and SI groups, respectively. TLI-cultured embryos had similar genome-wide methylation patterns to SI-cultured embryos. There were no significant differences in the methylation and transcription levels of transposable elements and imprinted control regions. Although a total of 198 differentially methylated genes (DMGs) were identified, only five DMGs had significantly different transcription levels between the two groups. CONCLUSIONS This is the first study to compare the DNA methylation profiles of embryos cultured in TLI and SI and will provide a foundation for evaluating the safety of TLI application in assisted reproductive technologies. However, further study with a larger cohort of samples was needed for the data validation.
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Affiliation(s)
- Ling Zhu
- Chongqing Key Laboratory of Human Embryo Engineering, Center for Reproductive Medicine, Women and Children's Hospital of Chongqing Medical University, Chongqing, China
- Chongqing Clinical Research Center for Reproductive Medicine, Chongqing Health Center for Women and Children, Chongqing, China
| | - Xi Zeng
- Chongqing Key Laboratory of Human Embryo Engineering, Center for Reproductive Medicine, Women and Children's Hospital of Chongqing Medical University, Chongqing, China
- Chongqing Clinical Research Center for Reproductive Medicine, Chongqing Health Center for Women and Children, Chongqing, China
| | - Weiwei Liu
- Chongqing Key Laboratory of Human Embryo Engineering, Center for Reproductive Medicine, Women and Children's Hospital of Chongqing Medical University, Chongqing, China
- Chongqing Clinical Research Center for Reproductive Medicine, Chongqing Health Center for Women and Children, Chongqing, China
| | - Wei Han
- Chongqing Key Laboratory of Human Embryo Engineering, Center for Reproductive Medicine, Women and Children's Hospital of Chongqing Medical University, Chongqing, China
- Chongqing Clinical Research Center for Reproductive Medicine, Chongqing Health Center for Women and Children, Chongqing, China
| | - Guoning Huang
- Chongqing Key Laboratory of Human Embryo Engineering, Center for Reproductive Medicine, Women and Children's Hospital of Chongqing Medical University, Chongqing, China.
- Chongqing Clinical Research Center for Reproductive Medicine, Chongqing Health Center for Women and Children, Chongqing, China.
| | - Jingyu Li
- Chongqing Key Laboratory of Human Embryo Engineering, Center for Reproductive Medicine, Women and Children's Hospital of Chongqing Medical University, Chongqing, China.
- Chongqing Clinical Research Center for Reproductive Medicine, Chongqing Health Center for Women and Children, Chongqing, China.
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11
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Suebthawinkul C, Babayev E, Zhou LT, Lee HC, Duncan FE. Quantitative morphokinetic parameters identify novel dynamics of oocyte meiotic maturation and cumulus expansion†. Biol Reprod 2022; 107:1097-1112. [PMID: 35810327 PMCID: PMC9562117 DOI: 10.1093/biolre/ioac139] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2022] [Revised: 05/30/2022] [Accepted: 06/30/2022] [Indexed: 12/05/2022] Open
Abstract
Meiotic maturation and cumulus expansion are essential for the generation of a developmentally competent gamete, and both processes can be recapitulated in vitro. We used a closed time-lapse incubator (EmbryoScope+™) to establish morphokinetic parameters of meiotic progression and cumulus expansion in mice and correlated these outcomes with egg ploidy. The average time to germinal vesicle breakdown (GVBD), time to first polar body extrusion (PBE), and duration of meiosis I were 0.91 ± 0.01, 8.82 ± 0.06, and 7.93 ± 0.06 h, respectively. The overall rate of cumulus layer expansion was 0.091 ± 0.002 μm/min, and the velocity of expansion peaked during the first 8 h of in vitro maturation (IVM) and then slowed. IVM of oocytes exposed to Nocodazole, a microtubule disrupting agent, and cumulus oocyte complexes (COCs) to 4-methylumbelliferone, a hyaluronan synthesis inhibitor, resulted in a dose-dependent perturbation of morphokinetics, thereby validating the system. The incidence of euploidy following IVM was >90% for both denuded oocytes and intact COCs. No differences were observed between euploid and aneuploid eggs with respect to time to GVBD (0.90 ± 0.22 vs. 0.97 ± 0.19 h), time to PBE (8.89 ± 0.98 vs. 9.10 ± 1.42 h), duration of meiosis I (8.01 ± 0.91 vs. 8.13 ± 1.38 h), and overall rate and kinetics of cumulus expansion (0.089 ± 0.02 vs 0.088 ± 0.03 μm/min) (P > 0.05). These morphokinetic parameters provide novel quantitative and non-invasive metrics for the evaluation of meiotic maturation and cumulus expansion and will enable screening compounds that modulate these processes.
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Affiliation(s)
- Chanakarn Suebthawinkul
- Department of Obstetrics and Gynecology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
- Department of Obstetrics and Gynecology, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand
| | - Elnur Babayev
- Department of Obstetrics and Gynecology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | - Luhan Tracy Zhou
- Department of Obstetrics and Gynecology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | - Hoi Chang Lee
- Department of Obstetrics and Gynecology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | - Francesca E Duncan
- Department of Obstetrics and Gynecology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
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12
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Wang M, Zhu T, Liu C, Jin L, Fei P, Zhang B. Oviduct-mimicking microfluidic chips decreased the ROS concentration in the in vitro fertilized embryos of CD-1 mice. Biomed Pharmacother 2022; 154:113567. [PMID: 36007278 DOI: 10.1016/j.biopha.2022.113567] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2022] [Revised: 08/07/2022] [Accepted: 08/15/2022] [Indexed: 01/09/2023] Open
Abstract
BACKGROUND The process of the assisted reproductive technology (ART) cycle is extremely complicated, and various factors in each step may influence the final clinical outcomes; thus, optimizing culture conditions for embryos is crucial in the ART cycle, particularly when the traditional petri-dish method remains unchanged for decades. In the current study, we intend to culture embryos in a dynamic environment on chips to optimize the embryo culture conditions. METHODS Multilayer soft lithography technology was utilized to establish a microfluidics-based oviduct. Mouse primary oviduct epithelial cells were identified by immunofluorescence staining and then loaded into the chip to coculture with the embryos. The development potential parameters of embryos on chips with cells, on chips without cells, and in drops were compared, as well as reactive oxygen species (ROS) in embryos. RESULTS There were no obvious differences regarding the fertilization rate, 4-Cell embryo rate, cleavage rate, high-quality embryo rate, or blastocyst formation rate. However, the intracellular ROS levels in 4-Cell stage embryos on chips with cells were statistically significantly lower than those in drops (P < 0.001). This organ-on-chip device allowed the probability of mammalian embryo culture in a microfluidic-based manner. CONCLUSIONS Our findings demonstrated that this novel oviduct-on-chip model may optimize embryo culture conditions by reducing intracellular ROS levels, which may be a competent alternative to the existing stable embryo culture system.
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Affiliation(s)
- Meng Wang
- Reproductive Medicine Center, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Tingting Zhu
- School of Optical and Electronic Information, Wuhan National Laboratory for Optoelectronics, Huazhong University of Science and Technology, Wuhan, China
| | - Chang Liu
- Reproductive Medicine Center, Nanjing Drum Tower Hospital, The Affiliated Hospital of Nanjing University Medical School, China
| | - Lei Jin
- Reproductive Medicine Center, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Peng Fei
- School of Optical and Electronic Information, Wuhan National Laboratory for Optoelectronics, Huazhong University of Science and Technology, Wuhan, China
| | - Bo Zhang
- Reproductive Medicine Center, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.
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13
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The use of insulin-transferrin-selenium (ITS), and folic acid on individual in vitro embryo culture systems in cattle. Theriogenology 2022; 184:153-161. [DOI: 10.1016/j.theriogenology.2022.03.008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2021] [Revised: 03/09/2022] [Accepted: 03/09/2022] [Indexed: 11/21/2022]
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14
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Fancsovits P, Pribenszky C, Lehner A, Murber A, Kaszas Z, Nemes A, Urbancsek J. Prospective-randomized study comparing clinical outcomes of IVF treatments where embryos were cultured individually or in a microwell group culture dish. Biol Futur 2022; 73:229-236. [PMID: 35278201 DOI: 10.1007/s42977-022-00113-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2021] [Accepted: 02/17/2022] [Indexed: 10/18/2022]
Abstract
Culturing embryos together in a microdrop of media may improve embryo quality, based on the results of animal studies, however individual identification of the embryos in such a system is not possible. The microwell group culture dish contains 9 or 16 microwells with a minimal well-to-well distance and a specific well morphology that facilitates paracrine and autocrine effects. The microwell group culture dish enables individual identification of the embryos while providing the environment that comes with similar benefits as group culture. Our aim was to investigate whether embryo culture in the microwell group culture dish (Primo Vision Dish, Vitrolife) improves IVF outcomes compared to individual culture in human IVF treatment. Five hundred thirty-two IVF-ET cycles were enrolled in this prospective randomized study in a university hospital. IVF cycles were randomized into microwell group culture and individual culture groups. Primary outcome measure was clinical pregnancy rate and secondary outcome measures were embryo quality, fertilization, implantation, delivery and embryo utilization rates. Fertilization rate in ICSI cycles was significantly higher in the microwell group culture group (70.6% vs. 64.9%, P = 0.001). Clinical pregnancy rate was 50.8% in the group culture and 40.6% in the individual culture (P = 0.022). Live birth rate was 41.5% in microwell and 32.9% in individual culture (P = 0.0496). Embryo utilization rate was higher in microwell group culture than in individual culture (80.6% vs. 75.0%; P < 0.001). Microwell group culture has a beneficial effect on IVF outcome and it also allows following up individual embryo development.ClinicalTrials.gov: NCT01774006.
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Affiliation(s)
- Peter Fancsovits
- Division of Assisted Reproduction, Department of Obstetrics and Gynaecology, Semmelweis University School of Medicine, Baross u. 27, Budapest, 1088, Hungary.
| | - Csaba Pribenszky
- Department of Animal Hygiene, Herdhealth and Veterinary Ethology, University of Veterinary Science, Budapest, Hungary
| | - Adam Lehner
- Division of Assisted Reproduction, Department of Obstetrics and Gynaecology, Semmelweis University School of Medicine, Baross u. 27, Budapest, 1088, Hungary
| | - Akos Murber
- Division of Assisted Reproduction, Department of Obstetrics and Gynaecology, Semmelweis University School of Medicine, Baross u. 27, Budapest, 1088, Hungary
| | - Zita Kaszas
- Division of Assisted Reproduction, Department of Obstetrics and Gynaecology, Semmelweis University School of Medicine, Baross u. 27, Budapest, 1088, Hungary
| | - Annamaria Nemes
- Division of Assisted Reproduction, Department of Obstetrics and Gynaecology, Semmelweis University School of Medicine, Baross u. 27, Budapest, 1088, Hungary
| | - Janos Urbancsek
- Division of Assisted Reproduction, Department of Obstetrics and Gynaecology, Semmelweis University School of Medicine, Baross u. 27, Budapest, 1088, Hungary
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15
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Shi C, Sun TC, Meng SH, Wang P, Liang R, Duan SN, Han HJ, Liu YN, Shen H, Chen X. Embryo Density and Its Neutrality in Day-3 Embryo Development: A Retrospective Cohort Study. Int J Endocrinol 2022; 2022:6368678. [PMID: 35313456 PMCID: PMC8934215 DOI: 10.1155/2022/6368678] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/04/2021] [Accepted: 02/09/2022] [Indexed: 12/03/2022] Open
Abstract
INTRODUCTION Many studies have shown that embryo density has an impact on day-3 embryo-developmental outcomes; however, embryo density remains controversial in clinical practice. We aimed to evaluate the association between embryo density and day-3 embryo-developmental outcomes in real world with the largest sample size. METHODS In 2018, we identified 10941 day-3 embryos from all female patients (n = 1568) in the study. The embryos were allocated to three embryonic densities: 30 μl/embryo (individual culture), 15 μl/embryo, and 10 μl/embryo (group culture). The primary outcomes were cleaving speed, quality, and proportion of successful implantations. The generalized estimate equation (GEE) model was used both in the univariate analysis and multivariable logistic regression analyses to investigate the relationship between embryo density and embryo-developmental outcomes. RESULTS There were 3064, 5695, and 2182 embryos in the 30 μl/embryo group, 15 μl/embryo group, and 10 μl/embryo group, respectively. The proportions of 7-10 cell embryos were 57.2%, 56.1%, and 58.3% in three densities with no statistical significance (P=0.37), respectively. The proportions of morphologically good embryos were 20%, 20.3%, and 20% in three densities with no statistical significance (P=0.85), respectively. Proportions of implanted embryos were 37.7%, 37.1%, and 27.8% with no statistical significance (P=0.36), respectively. After adjustment for confounders, which were significant in the univariate analysis, the embryo density was still not associated with day-3 embryo-cleaving speed, day-3 embryo quality, and day-3 embryo-implanting potential (all P > 0.05). CONCLUSION In a 30 μl microdrop, the culturing embryos with embryo densities of 15, 10, and 30 μl/embryo (from zygotes to day 3) had similar developmental outcomes. The embryo density had no impact on day-3 embryo development.
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Affiliation(s)
- Cheng Shi
- Reproductive Medical Center, Peking University People's Hospital, Peking University, Beijing 100044, China
| | - Tie Cheng Sun
- Department of Obstetrics and Gynecology, Peking University International Hospital, Beijing 102206, China
| | - Shi Hui Meng
- Reproductive Medical Center, Peking University People's Hospital, Peking University, Beijing 100044, China
| | - Ping Wang
- Reproductive Medical Center, Peking University People's Hospital, Peking University, Beijing 100044, China
| | - Rong Liang
- Reproductive Medical Center, Peking University People's Hospital, Peking University, Beijing 100044, China
| | - Sheng Nan Duan
- Reproductive Medical Center, Peking University People's Hospital, Peking University, Beijing 100044, China
| | - Hong Jing Han
- Reproductive Medical Center, Peking University People's Hospital, Peking University, Beijing 100044, China
| | - Ya Nan Liu
- Department of Obstetrics and Gynecology, Second Affiliated Hospital of Soochow University, Suzhou 215006, China
| | - Huan Shen
- Reproductive Medical Center, Peking University People's Hospital, Peking University, Beijing 100044, China
| | - Xi Chen
- Reproductive Medical Center, Peking University People's Hospital, Peking University, Beijing 100044, China
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16
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Vajta G, Parmegiani L, Machaty Z, Chen WB, Yakovenko S. Back to the future: optimised microwell culture of individual human preimplantation stage embryos. J Assist Reprod Genet 2021; 38:2563-2574. [PMID: 33864207 PMCID: PMC8581087 DOI: 10.1007/s10815-021-02167-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2020] [Accepted: 03/22/2021] [Indexed: 02/01/2023] Open
Abstract
Although in vitro culture of human embryos is a crucial step in assisted reproduction, the lack of focused research hampers worldwide standardisation and consistent outcomes. Only 1.2% of research papers published in five leading journals in human reproduction in 2019 focused on in vitro culture conditions, creating the impression that the optimisation process has approached its limits. On the other hand, in vitro culture of mammalian embryos is based on old principles, while there is no consensus on basic issues as density, time, medium change, gas atmosphere and small technical details including the way of drop preparation. This opinion paper aims to highlight and analyse the slow advancement in this field and stimulate research for simple and affordable solutions to meet the current requirements. A possible way for advancement is discussed in detail. Selection of embryos with the highest developmental competence requires individual culture and modification of the widely used "drop under oil" approach. Current use of three-dimensional surfaces instead of large flat bottoms is restricted to time-lapse systems, but these wells are designed for optical clarity, not for the needs of embryos. The size and shape of the original microwells (Well of the Well; WOW) offer a practical and straightforward solution to combine the benefits of communal and individual incubation and improve the overall quality of cultured embryos.
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Affiliation(s)
- Gábor Vajta
- RVT Australia, Cairns, QLD 4870 Australia
- VitaVitro Biotech Co., Ltd., Shenzhen, China
| | | | - Zoltan Machaty
- Department of Animal Sciences, Purdue University, West Lafayette, IN USA
| | | | - Sergey Yakovenko
- Altravita IVF Clinic, Moscow, Russia
- Biophysics Department, Moscow State University, Moscow, Russia
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17
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Ma Y, Gu M, Chen L, Shen H, Pan Y, Pang Y, Miao S, Tong R, Huang H, Zhu Y, Sun L. Recent advances in critical nodes of embryo engineering technology. Theranostics 2021; 11:7391-7424. [PMID: 34158857 PMCID: PMC8210615 DOI: 10.7150/thno.58799] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2021] [Accepted: 05/13/2021] [Indexed: 12/21/2022] Open
Abstract
The normal development and maturation of oocytes and sperm, the formation of fertilized ova, the implantation of early embryos, and the growth and development of foetuses are the biological basis of mammalian reproduction. Therefore, research on oocytes has always occupied a very important position in the life sciences and reproductive medicine fields. Various embryo engineering technologies for oocytes, early embryo formation and subsequent developmental stages and different target sites, such as gene editing, intracytoplasmic sperm injection (ICSI), preimplantation genetic diagnosis (PGD), and somatic cell nuclear transfer (SCNT) technologies, have all been established and widely used in industrialization. However, as research continues to deepen and target species become more advanced, embryo engineering technology has also been developing in a more complex and sophisticated direction. At the same time, the success rate also shows a declining trend, resulting in an extension of the research and development cycle and rising costs. By studying the existing embryo engineering technology process, we discovered three critical nodes that have the greatest impact on the development of oocytes and early embryos, namely, oocyte micromanipulation, oocyte electrical activation/reconstructed embryo electrofusion, and the in vitro culture of early embryos. This article mainly demonstrates the efforts made by researchers in the relevant technologies of these three critical nodes from an engineering perspective, analyses the shortcomings of the current technology, and proposes a plan and prospects for the development of embryo engineering technology in the future.
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Affiliation(s)
- Youwen Ma
- School of Mechanical and Electric Engineering, Jiangsu Provincial Key Laboratory of Advanced Robotics, Soochow University, Suzhou 215123, China
| | - Mingwei Gu
- School of Mechanical and Electric Engineering, Jiangsu Provincial Key Laboratory of Advanced Robotics, Soochow University, Suzhou 215123, China
| | - Liguo Chen
- School of Mechanical and Electric Engineering, Jiangsu Provincial Key Laboratory of Advanced Robotics, Soochow University, Suzhou 215123, China
| | - Hao Shen
- School of Mechanical and Electric Engineering, Jiangsu Provincial Key Laboratory of Advanced Robotics, Soochow University, Suzhou 215123, China
| | - Yifan Pan
- School of Mechanical and Electric Engineering, Jiangsu Provincial Key Laboratory of Advanced Robotics, Soochow University, Suzhou 215123, China
| | - Yan Pang
- School of Mechanical and Electric Engineering, Jiangsu Provincial Key Laboratory of Advanced Robotics, Soochow University, Suzhou 215123, China
| | - Sheng Miao
- School of Mechanical and Electric Engineering, Jiangsu Provincial Key Laboratory of Advanced Robotics, Soochow University, Suzhou 215123, China
| | - Ruiqing Tong
- Cardiology, Dushuhu Public Hospital Affiliated to Soochow University, Suzhou 215000, China
| | - Haibo Huang
- School of Mechanical and Electric Engineering, Jiangsu Provincial Key Laboratory of Advanced Robotics, Soochow University, Suzhou 215123, China
| | - Yichen Zhu
- Jiangsu Key Laboratory of Neuropsychiatric Diseases and Cambridge-Suda Genomic Resource Center, Soochow University, Suzhou 215123, China
| | - Lining Sun
- School of Mechanical and Electric Engineering, Jiangsu Provincial Key Laboratory of Advanced Robotics, Soochow University, Suzhou 215123, China
- State Key Laboratory of Robotics & Systems, Harbin Institute of Technology, Harbin, China
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18
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Ferrick L, Lee YSL, Gardner DK. Metabolic activity of human blastocysts correlates with their morphokinetics, morphological grade, KIDScore and artificial intelligence ranking. Hum Reprod 2021; 35:2004-2016. [PMID: 32829415 DOI: 10.1093/humrep/deaa181] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2020] [Revised: 06/18/2020] [Indexed: 01/15/2023] Open
Abstract
STUDY QUESTION Is there a relationship between blastocyst metabolism and biomarkers of embryo viability? SUMMARY ANSWER Blastocysts with higher developmental potential and a higher probability of resulting in a viable pregnancy consume higher levels of glucose and exhibit distinct amino acid profiles. WHAT IS KNOWN ALREADY Morphological and morphokinetic analyses utilized in embryo selection provide insight into developmental potential, but alone are unable to provide a direct measure of embryo physiology and inherent health. Glucose uptake is a physiological biomarker of viability and amino acid utilization is different between embryos of varying qualities. STUDY DESIGN, SIZE, DURATION Two hundred and nine human preimplantation embryos from 50 patients were cultured in a time-lapse incubator system in both freeze all and fresh transfer cycles. A retrospective analysis of morphokinetics, morphology (Gardner grade), KIDScore, artificial intelligence grade (EmbryoScore), glucose and amino acid metabolism, and clinical pregnancies was conducted. PARTICIPANTS/MATERIALS, SETTING, METHODS ICSI was conducted in all patients, who were aged ≤37 years and previously had no more than two IVF cycles. Embryos were individually cultured in a time-lapse incubator system, and those reaching the blastocyst stage had their morphokinetics annotated and were each assigned a Gardner grade, KIDScore and EmbryoScore. Glucose and amino acid metabolism were measured. Clinical pregnancies were confirmed by the presence of a fetal heartbeat at 6 weeks of gestation. MAIN RESULTS AND THE ROLE OF CHANCE Glucose consumption was at least 40% higher in blastocysts deemed of high developmental potential using either the Gardner grade (P < 0.01, n = 209), KIDScore (P < 0.05, n = 207) or EmbryoScore (P < 0.05, n = 184), compared to less viable blastocysts and in blastocysts that resulted in a clinical pregnancy compared to those that failed to implant (P < 0.05, n = 37). Additionally, duration of cavitation was inversely related to glucose consumption (P < 0.05, n = 200). Total amino acid consumption was significantly higher in blastocysts with an EmbryoScore higher than the cohort median score (P < 0.01, n = 185). Furthermore, the production of amino acids was significantly lower in blastocysts with a high Gardner grade (P < 0.05, n = 209), KIDScore (P < 0.05, n = 207) and EmbryoScore (P < 0.01, n = 184). LIMITATIONS, REASONS FOR CAUTION Samples were collected from patients who had ICSI treatment and from only one clinic. WIDER IMPLICATIONS OF THE FINDINGS These results confirm that metabolites, such as glucose and amino acids, are valid biomarkers of embryo viability and could therefore be used in conjunction with other systems to aid in the selection of a healthy embryo. STUDY FUNDING/COMPETING INTEREST(S) Work was supported by Virtus Health. D.K.G is contracted with Virtus Health. The other authors have no conflict of interest to declare. TRIAL REGISTRATION NUMBER N/A.
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Affiliation(s)
- Laura Ferrick
- School of BioSciences, University of Melbourne, Melbourne, VIC 3010, Australia
| | | | - David K Gardner
- School of BioSciences, University of Melbourne, Melbourne, VIC 3010, Australia.,Melbourne IVF, East Melbourne, Melbourne, VIC 3002, Australia
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Vajta G, Parmegiani L, Machaty Z, Chen WB, Yakovenko S. Back to the future: optimised microwell culture of individual human preimplantation stage embryos. J Assist Reprod Genet 2021. [PMID: 33864207 DOI: 10.1007/s10815-021-02167-4.] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/29/2022] Open
Abstract
Although in vitro culture of human embryos is a crucial step in assisted reproduction, the lack of focused research hampers worldwide standardisation and consistent outcomes. Only 1.2% of research papers published in five leading journals in human reproduction in 2019 focused on in vitro culture conditions, creating the impression that the optimisation process has approached its limits. On the other hand, in vitro culture of mammalian embryos is based on old principles, while there is no consensus on basic issues as density, time, medium change, gas atmosphere and small technical details including the way of drop preparation. This opinion paper aims to highlight and analyse the slow advancement in this field and stimulate research for simple and affordable solutions to meet the current requirements. A possible way for advancement is discussed in detail. Selection of embryos with the highest developmental competence requires individual culture and modification of the widely used "drop under oil" approach. Current use of three-dimensional surfaces instead of large flat bottoms is restricted to time-lapse systems, but these wells are designed for optical clarity, not for the needs of embryos. The size and shape of the original microwells (Well of the Well; WOW) offer a practical and straightforward solution to combine the benefits of communal and individual incubation and improve the overall quality of cultured embryos.
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Affiliation(s)
- Gábor Vajta
- RVT Australia, Cairns, QLD, 4870, Australia. .,VitaVitro Biotech Co., Ltd., Shenzhen, China.
| | | | - Zoltan Machaty
- Department of Animal Sciences, Purdue University, West Lafayette, IN, USA
| | | | - Sergey Yakovenko
- Altravita IVF Clinic, Moscow, Russia.,Biophysics Department, Moscow State University, Moscow, Russia
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20
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Zamfirescu RC, Day ML, Morris MB. mTORC1/2 signaling is downregulated by amino acid-free culture of mouse preimplantation embryos and is only partially restored by amino acid readdition. Am J Physiol Cell Physiol 2020; 320:C30-C44. [PMID: 33052068 DOI: 10.1152/ajpcell.00385.2020] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Development of the mammalian preimplantation embryo is influenced by autocrine/paracrine factors and the availability of nutrients. Deficiencies of these during in vitro culture reduce the success of assisted reproductive technologies. The mechanistic target of rapamycin complex 1 (mTORC1) pathway integrates external and internal signals, including those by amino acids (AAs), to promote normal preimplantation development. For this reason, AAs are often included in embryo culture media. In this study, we examined how withdrawal and addition of AAs to culture media modulate mTORC1 pathway activity compared with its activity in mouse embryos developed in vivo. Phosphorylation of signaling components downstream of mTORC1, namely, p70 ribosomal protein S6 kinase (p70S6K), ribosomal protein S6, and 4E binding protein 1 (4E-BP1), and that of protein kinase B (Akt), which lies upstream of mTORC1, changed significantly across stages of embryos developed in vivo. For freshly isolated blastocysts placed in vitro, the absence of AAs in the culture medium, even for a few hours, decreased mTORC1 signaling, which could only be partially restored by their addition. Long-term culture of early embryos to blastocysts in the absence of AAs decreased mTORC1 signaling to a greater extent and again this could only be partially restored by their inclusion. This failure to fully restore is probably due to decreased phosphatidylinositol 3-kinase (PI3K)/Akt/mTORC2 signaling in culture, as indicated by decreased P-AktS473. mTORC2 lies upstream of mTORC1 and is insensitive to AAs, and its reduced activity probably results from loss of maternal/autocrine factors. These data highlight reduced mTORC1/2 signaling activity correlating with compromised development in vitro and show that the addition of AAs can only partially offset these effects.
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Affiliation(s)
- Radu C Zamfirescu
- Discipline of Physiology and Bosch Institute, Faculty of Medicine and Health, School of Medical Sciences, The University of Sydney, Camperdown, New South Wales, Australia
| | - Margot L Day
- Discipline of Physiology and Bosch Institute, Faculty of Medicine and Health, School of Medical Sciences, The University of Sydney, Camperdown, New South Wales, Australia
| | - Michael B Morris
- Discipline of Physiology and Bosch Institute, Faculty of Medicine and Health, School of Medical Sciences, The University of Sydney, Camperdown, New South Wales, Australia
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21
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Lundin K, Park H. Time-lapse technology for embryo culture and selection. Ups J Med Sci 2020; 125:77-84. [PMID: 32096675 PMCID: PMC7720962 DOI: 10.1080/03009734.2020.1728444] [Citation(s) in RCA: 37] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/13/2020] [Revised: 02/04/2020] [Accepted: 02/06/2020] [Indexed: 12/20/2022] Open
Abstract
Culturing of human embryos in optimal conditions is crucial for a successful in vitro fertilisation (IVF) programme. In addition, the capacity to assess and rank embryos correctly for quality will allow for transfer of the potentially 'best' embryo first, thereby shortening the time to pregnancy, although not improving cumulative pregnancy and live birth rates. It will also encourage and facilitate the implementation of single embryo transfers, thereby increasing safety for mother and offspring. Time-lapse technology introduces the concept of stable culture conditions, in connection with the possibility of continuous viewing and documenting of the embryo throughout development. However, so far, even when embryo quality scoring is based on large datasets, or when using the time-lapse technology, the morphokinetic scores are still mainly based on subjective and intermittent annotations of morphology and timings. Also, the construction of powerful algorithms for widespread use is hampered by large variations in culture conditions between individual IVF laboratories. New methodology, involving machine learning, where every image from the time-lapse documentation is analysed by a computer programme, looking for patterns that link to outcome, may in the future provide a more accurate and non-biased embryo selection.
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Affiliation(s)
- Kersti Lundin
- Reproductive Medicine, Sahlgrenska University Hospital, Göteborg, Sweden
| | - Hannah Park
- Reproductive Medicine, Sahlgrenska University Hospital, Göteborg, Sweden
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22
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Apter S, Ebner T, Freour T, Guns Y, Kovacic B, Le Clef N, Marques M, Meseguer M, Montjean D, Sfontouris I, Sturmey R, Coticchio G. Good practice recommendations for the use of time-lapse technology †. Hum Reprod Open 2020; 2020:hoaa008. [PMID: 32206731 PMCID: PMC7081060 DOI: 10.1093/hropen/hoaa008] [Citation(s) in RCA: 91] [Impact Index Per Article: 22.8] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2019] [Revised: 12/05/2019] [Accepted: 01/29/2020] [Indexed: 12/26/2022] Open
Affiliation(s)
| | | | - Thomas Ebner
- Department of Gynecology, Obstetrics, and Gynecological Endocrinology, Kepler Universitätsklinikum, Linz, Austria
| | - Thomas Freour
- Médecine de la Reproduction, CHU de Nantes, Nantes, France
| | - Yves Guns
- Center for Reproductive Medicine, UZ Brussel, Brussels, Belgium
| | - Borut Kovacic
- Department of Reproductive Medicine and Gynecologic Endocrinology, Univerzitetni klinicni center Maribor, Maribor, Slovenia
| | - Nathalie Le Clef
- European Society of Human Reproduction and Embryology, Grimbergen, Belgium
| | | | - Marcos Meseguer
- IVF Laboratory, Instituto Valenciano de Infertilidad, Valencia, Spain
| | - Debbie Montjean
- Médecine et Biologie de la Reproduction, Hopital Saint Joseph, Marseille, France
| | | | - Roger Sturmey
- Centre for Atherothrombosis and Metabolic Disease, Hull York Medical School, University of Hull, Hull, UK
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23
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Gardner DK, Kuramoto T, Tanaka M, Mitzumoto S, Montag M, Yoshida A. Prospective randomized multicentre comparison on sibling oocytes comparing G-Series media system with antioxidants versus standard G-Series media system. Reprod Biomed Online 2020; 40:637-644. [PMID: 32299733 DOI: 10.1016/j.rbmo.2020.01.026] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2019] [Revised: 01/24/2020] [Accepted: 01/27/2020] [Indexed: 12/21/2022]
Abstract
RESEARCH QUESTION Does the inclusion of three antioxidants (A3), acetyl-l-carnitine (ALC), N-acetyl-l-cysteine (NAC) and alpha-lipoic acid (ALA) improve human embryo development and pregnancy potential? DESIGN Prospective randomized multicentre comparison of sibling oocytes. A total of 1563 metaphase II oocytes from 133 patients in two IVF centres. Day 3 embryo and day 5/6 blastocyst quality were assessed. Good embryo quality on day 3 was defined as 8 to 10 cells with even cells and low fragmentation; good quality blastocysts as 3BB or greater. Clinical outcome was assessed on transfers of fresh or vitrified-warmed blastocyst on day 5. RESULTS Of the two-pronuclei, 40.7% (G-Series) and 50.2% (G-Series with A3 group) resulted in good quality embryos on day 3 (P < 0.05). The implantation rate by fetal sac was 39.2% and 50.6%, and by fetal heartbeat was 37.8% and 47.1% for the G-Series and G-Series with A3 group, respectively. When stratified by female patient age, patients 35-40 years had an implantation rate by fetal sac and heart of 23.5% in the G-Series compared with 57.5% (P < 0.05) and 50.0% (P < 0.05) in the A3 group. The ongoing pregnancies in patients 35-40 years were significantly higher in the A3 group (50%) compared with the control (25.8%) (P < 0.05). CONCLUSIONS The presence of antioxidants during IVF and embryo culture for patients 35-40 years resulted in a significant increase in implantation and pregnancy rate. Supplementation of antioxidants to IVF and culture media may therefore improve the viability of human embryos in assisted reproductive technologies, plausibly through the reduction of oxidative stress.
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Affiliation(s)
- David K Gardner
- School of BioSciences, University of Melbourne, Parkville, Australia; Melbourne IVF, East Melbourne, Australia.
| | | | - Miho Tanaka
- Kiba Park Clinic, Reproductive Medicine, Tokyo, Japan
| | | | - Markus Montag
- ilabcomm GmbH, Eisenachstrasse 34, Sankt Augustin, Germany
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24
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Gu Z, Guo J, Wang H, Wen Y, Gu Q. Bioengineered microenvironment to culture early embryos. Cell Prolif 2020; 53:e12754. [PMID: 31916359 PMCID: PMC7046478 DOI: 10.1111/cpr.12754] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2019] [Revised: 12/13/2019] [Accepted: 12/16/2019] [Indexed: 12/12/2022] Open
Abstract
The abnormalities of early post-implantation embryos can lead to early pregnancy loss and many other syndromes. However, it is hard to study embryos after implantation due to the limited accessibility. The success of embryo culture in vitro can avoid the challenges of embryonic development in vivo and provide a powerful research platform for research in developmental biology. The biophysical and chemical cues of the microenvironments impart significant spatiotemporal effects on embryonic development. Here, we summarize the main strategies which enable researchers to grow embryos outside of the body while overcoming the implantation barrier, highlight the roles of engineered microenvironments in regulating early embryonic development, and finally discuss the future challenges and new insights of early embryo culture.
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Affiliation(s)
- Zhen Gu
- School of Chemistry and Biological EngineeringUniversity of Science and Technology BeijingBeijingChina
- CAS Key Laboratory of Bio‐inspired Materials and Interfacial ScienceTechnical Institute of Physics and ChemistryChinese Academy of SciencesBeijingChina
| | - Jia Guo
- State Key Laboratory of Membrane BiologyInstitute of ZoologyChinese Academy of SciencesBeijingChina
| | - Hongmei Wang
- State Key Laboratory of Stem Cell and Reproductive BiologyInstitute of ZoologyChinese Academy of SciencesBeijingChina
| | - Yongqiang Wen
- School of Chemistry and Biological EngineeringUniversity of Science and Technology BeijingBeijingChina
| | - Qi Gu
- State Key Laboratory of Membrane BiologyInstitute of ZoologyChinese Academy of SciencesBeijingChina
- University of Chinese Academy of SciencesBeijingChina
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25
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Ruíz M, Santamaría-López E, Blasco V, Hernáez MJ, Caligara C, Pellicer A, Fernández-Sánchez M, Prados N. Effect of Group Embryo Culture under Low-Oxygen Tension in Benchtop Incubators on Human Embryo Culture: Prospective, Randomized, Controlled Trial. Reprod Sci 2020; 27:1522-1533. [PMID: 31994003 DOI: 10.1007/s43032-020-00150-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2019] [Accepted: 12/30/2019] [Indexed: 10/25/2022]
Abstract
To evaluate the efficacy of group embryo culture under low-oxygen tension in benchtop incubators on human embryo development in vitro. The study was designed as a prospective, patient blind, randomized, controlled trial of a complex intervention. One hundred forty-eight women undergoing IVF were recruited in our fertility practice and randomized into two groups: intervention group (study culture strategy) or control group (control culture strategy). Intervention group embryos were cultured grouped under low-oxygen tension in benchtop incubators while control group embryos were cultured individually under atmospheric oxygen tension in large-box incubators. Using the study culture strategy, there were a significantly higher implantation rate (65.1% vs 49.2%; RR, 1.42; 95% CI, 1.17-1.73) and live birth delivery rate per embryo transfer (52.7% vs 39.5%; RR, 1.33; 95% CI, 1.02-1.75) with the first fresh embryo transfer. Cumulative implantation rate (56.7% vs 43.6%; RR, 1.30; 95% CI, 1.05-1.62) and cumulative live birth rate per embryo transfer (47.4% vs 36.2%; RR, 1.31; 95% CI, 1.01-1.69) were also statistically significantly increased in the study culture strategy. Human embryos exposed to our study culture condition strategy had statistically significant increased cumulative implantation rate and cumulative live birth rate per embryo transferred. Our findings suggest that this strategy specially favours poor quality embryos. Clinical Trial Registration Number: NCT01904006.
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Affiliation(s)
- Myriam Ruíz
- IVI-RMA Seville, Avda. República Argentina 58, ES-41011, Seville, Spain.,IVI Foundation, Instituto de Investigación Sanitaria La Fe (IIS La Fe), ES-46026, Valencia, Spain
| | - Esther Santamaría-López
- IVI-RMA Seville, Avda. República Argentina 58, ES-41011, Seville, Spain.,IVI Foundation, Instituto de Investigación Sanitaria La Fe (IIS La Fe), ES-46026, Valencia, Spain
| | - Víctor Blasco
- IVI-RMA Seville, Avda. República Argentina 58, ES-41011, Seville, Spain.,IVI Foundation, Instituto de Investigación Sanitaria La Fe (IIS La Fe), ES-46026, Valencia, Spain
| | - María José Hernáez
- IVI-RMA Seville, Avda. República Argentina 58, ES-41011, Seville, Spain.,IVI Foundation, Instituto de Investigación Sanitaria La Fe (IIS La Fe), ES-46026, Valencia, Spain
| | - Cinzia Caligara
- IVI-RMA Seville, Avda. República Argentina 58, ES-41011, Seville, Spain.,IVI Foundation, Instituto de Investigación Sanitaria La Fe (IIS La Fe), ES-46026, Valencia, Spain
| | - Antonio Pellicer
- IVI Foundation, Instituto de Investigación Sanitaria La Fe (IIS La Fe), ES-46026, Valencia, Spain.,Department of Pediatrics, Obstetrics and Gynecology, School of Medicine, Valencia University, ES-46010, Valencia, Spain.,IVI-RMA Rome, Largo Ildebrando Pizzetti 1, IT-00197, Rome, Italy
| | - Manuel Fernández-Sánchez
- IVI-RMA Seville, Avda. República Argentina 58, ES-41011, Seville, Spain. .,IVI Foundation, Instituto de Investigación Sanitaria La Fe (IIS La Fe), ES-46026, Valencia, Spain. .,Departamento de Cirugía, Universidad de Sevilla, Avda. Sánchez Pizjuan S/N, ES-41009, Seville, Spain. .,Departamento de Biología Molecular e Ingeniería Bioquímica, Universidad Pablo de Olavide, ES-41013, Seville, Spain.
| | - Nicolás Prados
- IVI-RMA Seville, Avda. República Argentina 58, ES-41011, Seville, Spain.,IVI Foundation, Instituto de Investigación Sanitaria La Fe (IIS La Fe), ES-46026, Valencia, Spain.,Departamento de Biología Molecular e Ingeniería Bioquímica, Universidad Pablo de Olavide, ES-41013, Seville, Spain
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26
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‘There is only one thing that is truly important in an IVF laboratory: everything’ Cairo Consensus Guidelines on IVF Culture Conditions. Reprod Biomed Online 2020; 40:33-60. [DOI: 10.1016/j.rbmo.2019.10.003] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2019] [Revised: 09/22/2019] [Accepted: 10/02/2019] [Indexed: 02/06/2023]
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27
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Deng T, Xie J, Ge H, Liu Q, Song X, Hu L, Meng L, Zhang C. Tauroursodeoxycholic acid (TUDCA) enhanced intracytoplasmic sperm injection (ICSI) embryo developmental competence by ameliorating endoplasmic reticulum (ER) stress and inhibiting apoptosis. J Assist Reprod Genet 2019; 37:119-126. [PMID: 31802346 DOI: 10.1007/s10815-019-01627-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2019] [Accepted: 11/01/2019] [Indexed: 01/16/2023] Open
Abstract
PURPOSE The objective of this study was to examine the effect of tauroursodeoxycholic acid (TUDCA) on intracytoplasmic sperm injection (ICSI) embryos by evaluating endoplasmic reticulum (ER) stress, apoptosis, and embryo developmental competence in vitro and in vivo. METHODS ER stress-associated genes and apoptosis-associated genes were measured and apoptosis index was analyzed. Embryo developmental competence was assessed in vitro and in vivo via the inner cell mass (ICM)/trophectoderm (TE) index, pregnancy and implantation rates, and birth rate. RESULTS The relative mRNA and protein expression of binding immunoglobulin protein (BIP) was significantly higher in the ICSI embryo group without TUDCA treatment (ICSI-C) than in the in vitro fertilization (IVF) group and in the ICSI embryo group with TUDCA treatment (200 μM) (ICSI-T), while TUDCA ameliorated ER stress in ICSI embryos. Embryos in the ICSI-C group showed a higher apoptosis index than those in the IVF group and ICSI-T group, and there was no significant difference between the IVF group and ICSI-T group. TUDCA can significantly improve ICSI embryo developmental competence in vitro and in vivo based on the ICM/TE index, pregnancy and implantation rates, and birth rate. CONCLUSION ICSI embryos manifested high ER stress and high apoptosis, while TUDCA ameliorated ER stress and reduced apoptosis in ICSI embryos. TUDCA can significantly improve the developmental competence of ICSI embryos in vitro and in vivo. This study provides a new idea for improving the efficiency of ICSI, and it will also have a positive effect on the development of assisted reproduction technologies for humans and other animals.
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Affiliation(s)
- Tengfei Deng
- Reproductive Medical Center, Henan Provincial People's Hospital, 7 Weiwu Rd, Zhengzhou City, 450003, Henan, China.,Reproductive Medical Center, People's Hospital of Zhengzhou University, 7 Weiwu Rd, Zhengzhou City, 450003, Henan, China.,Reproductive Medical Center, Henan Provincial People's Hospital, School of Clinical Medicine, Henan University, 7 Weiwu Rd, Zhengzhou City, 450003, Henan, China
| | - Juanke Xie
- Reproductive Medical Center, Henan Provincial People's Hospital, 7 Weiwu Rd, Zhengzhou City, 450003, Henan, China.,Reproductive Medical Center, People's Hospital of Zhengzhou University, 7 Weiwu Rd, Zhengzhou City, 450003, Henan, China.,Reproductive Medical Center, Henan Provincial People's Hospital, School of Clinical Medicine, Henan University, 7 Weiwu Rd, Zhengzhou City, 450003, Henan, China
| | - Hengtao Ge
- Reproductive Medical Center, Henan Provincial People's Hospital, 7 Weiwu Rd, Zhengzhou City, 450003, Henan, China.,Reproductive Medical Center, People's Hospital of Zhengzhou University, 7 Weiwu Rd, Zhengzhou City, 450003, Henan, China.,Reproductive Medical Center, Henan Provincial People's Hospital, School of Clinical Medicine, Henan University, 7 Weiwu Rd, Zhengzhou City, 450003, Henan, China
| | - Qi Liu
- Reproductive Medical Center, Henan Provincial People's Hospital, 7 Weiwu Rd, Zhengzhou City, 450003, Henan, China.,Reproductive Medical Center, People's Hospital of Zhengzhou University, 7 Weiwu Rd, Zhengzhou City, 450003, Henan, China.,Reproductive Medical Center, Henan Provincial People's Hospital, School of Clinical Medicine, Henan University, 7 Weiwu Rd, Zhengzhou City, 450003, Henan, China
| | - Xiaobing Song
- Reproductive Medical Center, Henan Provincial People's Hospital, 7 Weiwu Rd, Zhengzhou City, 450003, Henan, China.,Reproductive Medical Center, People's Hospital of Zhengzhou University, 7 Weiwu Rd, Zhengzhou City, 450003, Henan, China.,Reproductive Medical Center, Henan Provincial People's Hospital, School of Clinical Medicine, Henan University, 7 Weiwu Rd, Zhengzhou City, 450003, Henan, China
| | - Lin Hu
- Reproductive Medical Center, Henan Provincial People's Hospital, 7 Weiwu Rd, Zhengzhou City, 450003, Henan, China.,Reproductive Medical Center, People's Hospital of Zhengzhou University, 7 Weiwu Rd, Zhengzhou City, 450003, Henan, China.,Reproductive Medical Center, Henan Provincial People's Hospital, School of Clinical Medicine, Henan University, 7 Weiwu Rd, Zhengzhou City, 450003, Henan, China
| | - Li Meng
- Reproductive Medical Center, Henan Provincial People's Hospital, 7 Weiwu Rd, Zhengzhou City, 450003, Henan, China.,Reproductive Medical Center, People's Hospital of Zhengzhou University, 7 Weiwu Rd, Zhengzhou City, 450003, Henan, China.,Reproductive Medical Center, Henan Provincial People's Hospital, School of Clinical Medicine, Henan University, 7 Weiwu Rd, Zhengzhou City, 450003, Henan, China.,LA IVF Clinic, Los Angeles, CA, USA
| | - Cuilian Zhang
- Reproductive Medical Center, Henan Provincial People's Hospital, 7 Weiwu Rd, Zhengzhou City, 450003, Henan, China. .,Reproductive Medical Center, People's Hospital of Zhengzhou University, 7 Weiwu Rd, Zhengzhou City, 450003, Henan, China. .,Reproductive Medical Center, Henan Provincial People's Hospital, School of Clinical Medicine, Henan University, 7 Weiwu Rd, Zhengzhou City, 450003, Henan, China.
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28
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Parameters of the Mouse Embryo Assay that affect detection of peroxides in mineral oil. Reprod Biomed Online 2019; 39:547-555. [DOI: 10.1016/j.rbmo.2019.05.008] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2019] [Revised: 05/08/2019] [Accepted: 05/08/2019] [Indexed: 11/19/2022]
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29
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Kelley RL, Gardner DK. Individual culture and atmospheric oxygen during culture affect mouse preimplantation embryo metabolism and post-implantation development. Reprod Biomed Online 2019; 39:3-18. [PMID: 31122833 DOI: 10.1016/j.rbmo.2019.03.102] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2018] [Revised: 01/30/2019] [Accepted: 03/06/2019] [Indexed: 12/30/2022]
Abstract
RESEARCH QUESTION Does single embryo culture under atmospheric or reduced oxygen alter preimplantation metabolism and post-implantation development compared with culture in groups? DESIGN Mouse embryos were cultured under 5% or 20% oxygen, individually or in groups of 10. Spent media were analysed after 48, 72 and 96 h of culture. Blastocysts were assessed by outgrowth assay or transferred to pseudo-pregnant recipients, and fetal and placental weight, length and morphology were assessed. RESULTS Compared with group culture, individually cultured blastocysts had lower net consumption of glucose and aspartate and higher glutamate production. Atmospheric oxygen reduced uptake of glucose and aspartate and increased production of glutamate and ornithine compared with 5% oxygen. Combining 20% oxygen and single culture resulted in further metabolic changes: decreased leucine, methionine and threonine consumption. Under 5% oxygen, individual culture decreased placental labyrinth area but had no other effects on fetal and placental development or outgrowth size compared with group culture. Under 20% oxygen, however, individual culture reduced outgrowth size and fetal and placental weight compared with group-cultured embryos. CONCLUSIONS Preimplantation metabolism of glucose and amino acids is altered by both oxygen and individual culture, and fetal weight is reduced by individual culture under atmospheric oxygen but not 5% oxygen. This study raises concerns regarding the increasing prevalence of single embryo culture in human IVF and adds to the existing evidence regarding the detrimental effects of atmospheric oxygen during embryo culture. Furthermore, these data demonstrate the cumulative nature of stress during embryo culture and highlight the importance of optimizing each element of the culture system.
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Affiliation(s)
- Rebecca L Kelley
- School of BioSciences, The University of Melbourne, Parkville Victoria 3010, Australia
| | - David K Gardner
- School of BioSciences, The University of Melbourne, Parkville Victoria 3010, Australia.
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30
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Saadeldin IM, Jang G. Sex differences in single IVF-derived bovine embryo cultured in chemically defined medium. Int J Vet Sci Med 2019; 6:S78-S80. [PMID: 30761326 PMCID: PMC6161862 DOI: 10.1016/j.ijvsm.2018.01.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2017] [Revised: 01/07/2018] [Accepted: 01/07/2018] [Indexed: 11/24/2022] Open
Abstract
Single embryo culture is essential for culturing embryos derived from few oocytes obtained from elite cows through ultrasonography guidance. Bovine in vitro fertilization (IVF) and individual embryo culture is a challenge as it generally leads to impaired embryo development. In this study, we explored the embryonic development and the sex ratio of IVF-derived bovine embryo cultured individually in chemically defined two-step culture medium. Total 63 cumulus-oocyte complexes were collected, in vitro matured, in vitro fertilized and the resultant fertilized oocytes were randomly cultured individually (4 trials, 15–16 oocytes each) in microdrops of 5 µL of a chemically defined two-step culture medium. Blastocysts were counted in every trial (n = 32, 50.79%) and all of them were used for both genomic DNA and total RNA extraction, cDNA synthesis and PCR using specific primers for GAPDH, GDP6, XIST and SRY genes. Results showed significant difference in expression of XIST (positive expression in 11 blastocysts) and SRY (positive expression in 21 blastocysts) mRNAs, P < .05. This result supports the hypothesis of sexual dimorphism among the pre-implantation in vitro produced embryos and provides an efficient medium for single bovine embryos in vitro production.
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Affiliation(s)
- Islam M Saadeldin
- Department of Animal Production, College of Food and Agricultural Sciences, King Saud University, 11451 Riyadh, Saudi Arabia.,Department of Physiology, Faculty of Veterinary Medicine, Zagazig University, 44519 Zagazig, Egypt
| | - Goo Jang
- Department of Theriogenology and Biotechnology, College of Veterinary Medicine, Seoul National University, Seoul, 08826, South Korea.,Emergence Center for Food-Medicine Personalized Therapy System, Advanced Institute of Convergence Technology, Seoul National University, Gyeonggi-Do, 16629, South Korea
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31
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Huang TT, Huang DH, Ahn HJ, Arnett C, Huang CT. Early blastocyst expansion in euploid and aneuploid human embryos: evidence for a non-invasive and quantitative marker for embryo selection. Reprod Biomed Online 2019; 39:27-39. [PMID: 31130402 DOI: 10.1016/j.rbmo.2019.01.010] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2018] [Revised: 12/14/2018] [Accepted: 01/17/2019] [Indexed: 12/27/2022]
Abstract
RESEARCH QUESTION How can the kinetics of human blastocyst expansion be used to evaluate an embryo's ploidy identified using preimplantation genetic testing for aneuploidy (PGT-A)? DESIGN This was a retrospective observational study of 188 autologous blastocysts from 34 sequential treatment cycles using PGT-A and blastocyst biopsy. Using time-lapse imaging, blastocyst expansion was evaluated using a quantitative standardized expansion assay (qSEA). Trophectoderm cell division was examined in selected, unbiopsied embryos (n = 7) to evaluate the contribution of mitosis to the expansion rate. RESULTS The averaged euploid blastocyst expansion rate was significantly (52.8%) faster than in aneuploid blastocysts (P = 0.0041). Scatterplots, representing 'expansion maps', revealed that both populations showed a similarly overlapping distribution of blastocyst formation times at 80-140 h from fertilization. Euploidy and aneuploidy were better distinguished in regions of higher and lower expansion, respectively, in expansion maps. Based upon the expansion slopes, rank-ordering of individual embryos within cohorts resulted in more than 90% euploid embryos in the first two ranks in patients less than 35 years of age. Additional detailed time-lapse image analysis provided evidence that rapid expansion was associated with robust, integrative cellular mitosis in trophectoderm cells. CONCLUSIONS The kinetics of human blastocyst expansion are related to an embryo's ploidy. These preliminary observations describe a new quantitative, non-invasive approach to embryo assessment that may be useful to identify single blastocysts for transfer, particularly in younger patient groups. However, this approach may also be useful for euploid embryo selection after PGT-A. The results support the hypothesis that aneuploidy universally impairs general cellular processes, including cell division, in differentiated cells.
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Affiliation(s)
- Thomas Tf Huang
- Department of Obstetrics and Gynecology and Women's Health, John A. Burns School of Medicine, Honolulu Hawaii, USA; Pacific In Vitro Fertilization Institute, Honolulu Hawaii, USA.
| | - David H Huang
- Pacific In Vitro Fertilization Institute, Honolulu Hawaii, USA
| | - Hyeong J Ahn
- Department of Complementary and Integrative Medicine, University of Hawaii John A. Burns School of Medicine, Honolulu Hawaii, USA
| | - Christina Arnett
- Advanced Reproductive Center of Hawaii, Kapiolani Medical Center for Women and Children, Honolulu Hawaii, USA
| | - Christopher Tf Huang
- Advanced Reproductive Center of Hawaii, Kapiolani Medical Center for Women and Children, Honolulu Hawaii, USA
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Risks in Surrogacy Considering the Embryo: From the Preimplantation to the Gestational and Neonatal Period. BIOMED RESEARCH INTERNATIONAL 2018; 2018:6287507. [PMID: 30112409 PMCID: PMC6077588 DOI: 10.1155/2018/6287507] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 12/01/2017] [Accepted: 07/09/2018] [Indexed: 01/01/2023]
Abstract
Surrogacy is an assisted reproduction-based approach in which the intended parents assign the gestation and birth to another woman called the surrogate mother. The drivers of surrogacy refer largely to infertility, medical conditions, same-sex couples' parenting, and cases of diversity regarding sexual identity and orientation. Surrogacy consists of a valid option for a variety of conditions or circumstances ranging from medical to social reasons. However, surrogacy may be associated with risks during the preimplantation, prenatal, and neonatal period. It became obvious during the exhaustive literature research that data on surrogacy and its association with factors specific to the IVF practice and the options available were not fully represented. Could it be that surrogacy management adds another level of complexity to the process from the ovarian stimulation, the subsequent IVF cycle, and the techniques employed within the IVF and the Genetic Laboratory to the fetal, perinatal, and neonatal period? This work emphasizes the risks associated with surrogacy with respect to the preimplantation embryo, the fetus, and the infant. Moreover, it further calls for larger studies reporting on surrogacy and comparing the surrogate management to that of the routine IVF patient in order to avoid suboptimal management of a surrogate cycle. This is of particular importance in light of the fact that the surrogate cycle may include not only the surrogate but also the egg donor, sperm donor, and the commissioning couple or single person.
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Exogenous growth factors do not affect the development of individually cultured murine embryos. J Assist Reprod Genet 2017; 35:523-531. [PMID: 29270871 DOI: 10.1007/s10815-017-1103-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2017] [Accepted: 11/29/2017] [Indexed: 12/21/2022] Open
Abstract
PURPOSE The objective of this study was to evaluate the effects of multiple growth factors on the development of individually cultured murine embryos. METHODS Embryos produced by in vitro fertilization using in vitro (IVM) or in vivo (IVO) matured oocytes from three strains of mice (CF1, Swiss Webster, B6D2F1) were cultured individually (10 μl) in the absence (control) or presence of growth factors (paf, epidermal growth factor [EGF], insulin-like growth factor 1 [IGF-1], and granulocyte-macrophage colony-stimulating factor [GM-CSF]). Blastocyst formation, hatching, and blastocyst cell numbers (trophectoderm, inner cell mass, and total) were evaluated on days 4 and 5 of culture. Post-hatching development of CF1 IVO embryos was also evaluated in vitro and in vivo. RESULTS The presence of growth factors did not improve the proportion of embryos forming blastocysts or initiating hatching for any of the types of embryos tested. The only significant (P < 0.05) effect of growth factors was a decrease in the proportion of embryos that formed blastocysts by day 5 in CF1 IVM embryos. The presence of growth factors also did not affect blastocyst cell numbers. For CF1 IVO embryos, the presence of growth factors during culture did not affect the proportion of embryos that attached to fibronectin-coated dishes, the size of the resulting outgrowths, or in vivo development following transfer. CONCLUSION Combinations of paf, EGF, GM-CSF, and IGF-1 did not improve development of murine embryos cultured individually in a sequential medium containing a defined protein source.
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Kelley RL, Gardner DK. Addition of interleukin-6 to mouse embryo culture increases blastocyst cell number and influences the inner cell mass to trophectoderm ratio. Clin Exp Reprod Med 2017; 44:119-125. [PMID: 29026717 PMCID: PMC5636923 DOI: 10.5653/cerm.2017.44.3.119] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2017] [Revised: 05/17/2017] [Accepted: 06/19/2017] [Indexed: 11/06/2022] Open
Abstract
Objective In vitro culture of preimplantation embryos is improved by grouping embryos together in a drop of media. Individually cultured embryos are deprived of paracrine factors; with this in mind, we investigated whether the addition of a single embryo-secreted factor, interleukin-6 (IL-6), could improve the development of individually cultured embryos. Methods Mouse embryos were cultured individually in 2 µL of G1/G2 media in 5% oxygen and supplemented with a range of doses of recombinant mouse or human IL-6. Results Mouse IL-6 increased hatching at doses of 0.01 and 10 ng/mL compared to the control (93% and 93% vs. 78%, p<0.05) and increased the total number of cells at a dose of 0.1 ng/mL compared to the control (101.95±3.36 vs. 91.31±3.33, p<0.05). In contrast, the highest dose of 100 ng/mL reduced the total number of cells (79.86±3.29, p<0.05). Supplementation with human IL-6 had a different effect, with no change in hatching or total cell numbers, but an increase in the percentage of inner cell mass per embryo at doses of 0.1, 1, and 100 ng/mL compared to the control (22.9%±1.1%, 23.3%±1.1%, and 23.1%±1.1% vs. 19.5%±1.0%, p<0.05). Conclusion These data show that IL-6 improved mouse embryo development when cultured individually in complex media; however, an excess of IL-6 may be detrimental. Additionally, these data indicate that there is some cross-species benefit of human IL-6 for mouse embryos, but possibly through a different mechanism than for mouse IL-6.
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Affiliation(s)
- Rebecca L Kelley
- School of Biosciences, University of Melbourne, Parkville, Australia
| | - David K Gardner
- School of Biosciences, University of Melbourne, Parkville, Australia
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Le Bras A, Hesters L, Gallot V, Tallet C, Tachdjian G, Frydman N. Shortening gametes co-incubation time improves live birth rate for couples with a history of fragmented embryos. Syst Biol Reprod Med 2017. [DOI: 10.1080/19396368.2017.1336581] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Affiliation(s)
- Anne Le Bras
- AP-HP, Antoine Béclère Hospital, Reproductive Biology Unit, Clamar, France
| | - Laetitia Hesters
- AP-HP, Antoine Béclère Hospital, Reproductive Biology Unit, Clamar, France
| | | | - Cathie Tallet
- AP-HP, Antoine Béclère Hospital, Reproductive Biology Unit, Clamar, France
| | - Gerard Tachdjian
- AP-HP, Antoine Béclère Hospital, Reproductive Biology Unit, Clamar, France
| | - Nelly Frydman
- AP-HP, Antoine Béclère Hospital, Reproductive Biology Unit, Clamar, France
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Abstract
The phenotype of the human embryo conceived through in vitro fertilization (IVF), that is its morphology, developmental kinetics, physiology and metabolism, can be affected by numerous components of the laboratory and embryo culture system (which comprise the laboratory environment). The culture media formulation is important in determining embryo phenotype, but this exists within a culture system that includes oxygen, temperature, pH and whether an embryo is cultured individually or in a group, all of which can influence embryo development. Significantly, exposure of an embryo to one suboptimal component of the culture system of laboratory typically predisposes the embryo to become more vulnerable to a second stressor, as has been well documented for atmospheric oxygen and individual culture, as well as for oxygen and ammonium. Furthermore, the inherent viability of the human embryo is derived from the quality of the gametes from which it is created. Patient age, aetiology, genetics, lifestyle (as well as ovarian stimulation in women) are all known to affect the developmental potential of gametes and hence the embryo. Thus, as well as considering the impact of the IVF laboratory environment, one needs to be aware of the status of the infertile couple, as this impacts how their gametes and embryos will respond to an in vitro environment. Although far from straight forward, analysing the interactions that exist between the human embryo and its environment will facilitate the creation of more effective and safer treatments for the infertile couple.
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