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Reproduction, Fertility and Development Reproduction, Fertility and Development Society
Vertebrate reproductive science and technology
RESEARCH ARTICLE

Culture environment regulates amino acid turnover and glucose utilisation in human ES cells

Joy Rathjen A B , Christine Yeo A , Charlotte Yap A , Boon Siang Nicholas Tan A , Peter D. Rathjen A B and David K. Gardner A C
+ Author Affiliations
- Author Affiliations

A Department of Zoology, University of Melbourne, Parkville, Vic. 3010, Australia.

B Menzies Research Institute Tasmania, University of Tasmania, 17 Liverpool Street, Hobart, Tas. 7000, Australia.

C Corresponding author. Email: david.gardner@unimelb.edu.au

Reproduction, Fertility and Development 26(5) 703-716 https://doi.org/10.1071/RD12276
Submitted: 23 August 2012  Accepted: 24 April 2013   Published: 13 June 2013

Abstract

Human embryonic stem (ES) cells have been proposed as a renewable source of pluripotent cells that can be differentiated into various cell types for use in research, drug discovery and in the emerging area of regenerative medicine. Exploitation of this potential will require the development of ES cell culture conditions that promote pluripotency and a normal cell metabolism, and quality control parameters that measure these outcomes. There is, however, relatively little known about the metabolism of pluripotent cells or the impact of culture environment and differentiation on their metabolic pathways. The effect of two commonly used medium supplements and cell differentiation on metabolic indicators in human ES cells were examined. Medium modifications and differentiation were compared in a chemically defined and feeder-independent culture system. Adding serum increased glucose utilisation and altered amino acid turnover by the cells, as well as inducing a small proportion of the cells to differentiate. Cell differentiation could be mitigated by inhibiting p38 mitogen-activated protein kinase (p38 MAPK activity). The addition of Knockout Serum Replacer also increased glucose uptake and changed amino acid turnover by the cells. These changes were distinct from those induced by serum and occurred in the absence of detectable differentiation. Induction of differentiation by bone morphogenetic protein 4 (BMP4), in contrast, did not alter metabolite turnover. Deviations from metabolite turnover by ES cells in fully defined medium demonstrated that culture environment can alter metabolite use. The challenge remains to understand the impact of metabolic changes on long-term cell maintenance and the functionality of derived cell populations.

Additional keywords: carbohydrate use, metabolomics, pluripotency.


References

Abaci, H. E., Truitt, R., Luong, E., Drazer, G., and Gerecht, S. (2010). Adaptation to oxygen deprivation in cultures of human pluripotent stem cells, endothelial progenitor cells and umbilical vein endothelial cells. Am. J. Physiol. Cell Physiol. 298, C1527–C1537.
Adaptation to oxygen deprivation in cultures of human pluripotent stem cells, endothelial progenitor cells and umbilical vein endothelial cells.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC3cXnvFams7o%3D&md5=4f00ec7eec2eaaeac578b896abfd99b2CAS | 20181925PubMed |

Adewumi, O., Aflatoonian, B., Ahrlund-Richter, L., Amit, M., Andrews, P. W., Beighton, G., Bello, P. A., Benvenisty, N., Berry, L. S., Bevan, S., Blum, B., Brooking, J., Chen, K. G., Choo, A. B., Churchill, G. A., Corbel, M., Damjanov, I., Draper, J. S., Dvorak, P., Emanuelsson, K., Fleck, R. A., Ford, A., Gertow, K., Gertsenstein, M., Gokhale, P. J., Hamilton, R. S., Hampl, A., Healy, L. E., Hovatta, O., Hyllner, J., Imreh, M. P., Itskovitz-Eldor, J., Jackson, J., Johnson, J. L., Jones, M., Kee, K., King, B. L., Knowles, B. B., Lako, M., Lebrin, F., Mallon, B. S., Manning, D., Mayshar, Y., McKay, R. D., Michalska, A. E., Mikkola, M., Mileikovsky, M., Minger, S. L., Moore, H. D., Mummery, C. L., Nagy, A., Nakatsuji, N., O’Brien, C. M., Oh, S. K., Olsson, C., Otonkoski, T., Park, K. Y., Passier, R., Patel, H., Patel, M., Pedersen, R., Pera, M. F., Piekarczyk, M. S., Pera, R. A., Reubinoff, B. E., Robins, A. J., Rossant, J., Rugg-Gunn, P., Schulz, T. C., Semb, H., Sherrer, E. S., Siemen, H., Stacey, G. N., Stojkovic, M., Suemori, H., Szatkiewicz, J., Turetsky, T., Tuuri, T., van den Brink, S., Vintersten, K., Vuoristo, S., Ward, D., Weaver, T. A., Young, L. A., and Zhang, W. (2007). Characterization of human embryonic stem-cell lines by the International Stem Cell Initiative. Nat. Biotechnol. 25, 803–816.
Characterization of human embryonic stem-cell lines by the International Stem Cell Initiative.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD2sXnsFaru7w%3D&md5=dab49aaa0d6a0f6da2b79c1b188c0866CAS | 17572666PubMed |

Akopian, V., Andrews, P. W., Beil, S., Benvenisty, N., Brehm, J., Christie, M., Ford, A., Fox, V., Gokhale, P. J., Healy, L., Holm, F., Hovatta, O., Knowles, B. B., Ludwig, T. E., McKay, R. D., Miyazaki, T., Nakatsuji, N., Oh, S. K., Pera, M. F., Rossant, J., Stacey, G. N., and Suemori, H. (2010). Comparison of defined culture systems for feeder-cell-free propagation of human embryonic stem cells. In Vitro Cell. Dev. Biol. Anim. 46, 247–258.
Comparison of defined culture systems for feeder-cell-free propagation of human embryonic stem cells.Crossref | GoogleScholarGoogle Scholar | 20186512PubMed |

Amps, K., Andrews, P. W., Anyfantis, G., Armstrong, L., Avery, S., Baharvand, H., Baker, J., Baker, D., Munoz, M. B., Beil, S., Benvenisty, N., Ben-Yosef, D., Biancotti, J. C., Bosman, A., Brena, R. M., Brison, D., Caisander, G., Camarasa, M. V., Chen, J., Chiao, E., Choi, Y. M., Choo, A. B., Collins, D., Colman, A., Crook, J. M., Daley, G. Q., Dalton, A., De Sousa, P. A., Denning, C., Downie, J., Dvorak, P., Montgomery, K. D., Feki, A., Ford, A., Fox, V., Fraga, A. M., Frumkin, T., Ge, L., Gokhale, P. J., Golan-Lev, T., Gourabi, H., Gropp, M., Lu, G., Hampl, A., Harron, K., Healy, L., Herath, W., Holm, F., Hovatta, O., Hyllner, J., Inamdar, M. S., Irwanto, A. K., Ishii, T., Jaconi, M., Jin, Y., Kimber, S., Kiselev, S., Knowles, B. B., Kopper, O., Kukharenko, V., Kuliev, A., Lagarkova, M. A., Laird, P. W., Lako, M., Laslett, A. L., Lavon, N., Lee, D. R., Lee, J. E., Li, C., Lim, L. S., Ludwig, T. E., Ma, Y., Maltby, E., Mateizel, I., Mayshar, Y., Mileikovsky, M., Minger, S. L., Miyazaki, T., Moon, S. Y., Moore, H., Mummery, C., Nagy, A., Nakatsuji, N., Narwani, K., Oh, S. K., Olson, C., Otonkoski, T., Pan, F., Park, I. H., Pells, S., Pera, M. F., Pereira, L. V., Qi, O., Raj, G. S., Reubinoff, B., Robins, A., Robson, P., Rossant, J., Salekdeh, G. H., Schulz, T. C., Sermon, K., Sheik Mohamed, J., Shen, H., Sherrer, E., Sidhu, K., Sivarajah, S., Skottman, H., Spits, C., Stacey, G. N., Strehl, R., Strelchenko, N., Suemori, H., Sun, B., Suuronen, R., Takahashi, K., Tuuri, T., Venu, P., Verlinsky, Y., Ward-van Oostwaard, D., Weisenberger, D. J., Wu, Y., Yamanaka, S., Young, L., and Zhou, Q. (2011). Screening ethnically diverse human embryonic stem cells identifies a chromosome 20 minimal amplicon conferring growth advantage. Nat. Biotechnol. 29, 1132–1144.
Screening ethnically diverse human embryonic stem cells identifies a chromosome 20 minimal amplicon conferring growth advantage.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC3MXhsFeitr3M&md5=9105a934b1227939b9cf4bc357a2b9b3CAS | 22119741PubMed |

Brand, K., Aichinger, S., Forster, S., Kupper, S., Neumann, B., Nurnberg, W., and Ohrisch, G. (1988). Cell-cycle-related metabolic and enzymatic events in proliferating rat thymocytes. Eur. J. Biochem. 172, 695–702.
Cell-cycle-related metabolic and enzymatic events in proliferating rat thymocytes.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaL1cXhs1Gqu7o%3D&md5=3653bf79b9f1a3bbd13f1b2824eec2acCAS | 3258238PubMed |

Brison, D. R., Houghton, F. D., Falconer, D., Roberts, S. A., Hawkhead, J., Humpherson, P. G., Lieberman, B. A., and Leese, H. J. (2004). Identification of viable embryos in IVF by non-invasive measurement of amino-acid turnover. Hum. Reprod. 19, 2319–2324.
Identification of viable embryos in IVF by non-invasive measurement of amino-acid turnover.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD2cXns1OmsrY%3D&md5=c71ef2a90a58811f60ab6e248e880548CAS | 15298971PubMed |

Bröer, A., Juelich, T., Vanslambrouck, J. M., Tietze, N., Solomon, P. S., Holst, J., Bailey, C. G., Rasko, J. E., and Bröer, S. (2011). Impaired nutrient signalling and body-weight control in a Na+-neutral amino-acid cotransporter (Slc6a19)-deficient mouse. J. Biol. Chem. 286, 26 638–26 651.
Impaired nutrient signalling and body-weight control in a Na+-neutral amino-acid cotransporter (Slc6a19)-deficient mouse.Crossref | GoogleScholarGoogle Scholar |

Bruhat, A., Jousse, C., Carraro, V., Reimold, A. M., Ferrara, M., and Fafournoux, P. (2000). Amino acids control mammalian gene transcription: activating transcription factor 2 is essential for the amino-acid responsiveness of the CHOP promoter. Mol. Cell. Biol. 20, 7192–7204.
Amino acids control mammalian gene transcription: activating transcription factor 2 is essential for the amino-acid responsiveness of the CHOP promoter.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD3cXms1Cjtb8%3D&md5=65ad220180a27976c6028f731aa8cb09CAS | 10982836PubMed |

Chang, X., and Wei, C. (2011). Glycolysis and rheumatoid arthritis. Int. J. Rheum. Dis. 14, 217–222.
Glycolysis and rheumatoid arthritis.Crossref | GoogleScholarGoogle Scholar | 21816017PubMed |

Cuenda, A., Rouse, J., Doza, Y., Meier, R., Cohen, P., Gallagher, T., Young, P., and Lee, J. (1995). SB 203580 is a specific inhibitor of a MAP kinase homologue which is stimulated by cellular stresses and interleukin-1. FEBS Lett. 364, 229–233.
SB 203580 is a specific inhibitor of a MAP kinase homologue which is stimulated by cellular stresses and interleukin-1.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaK2MXls12itL4%3D&md5=4ce71d3b93b31cb0ca61665649a2ade5CAS | 7750577PubMed |

DeBerardinis, R. J., Mancuso, A., Daikhin, E., Nissim, I., Yudkoff, M., Wehrli, S., and Thompson, C. B. (2007). Beyond aerobic glycolysis: transformed cells can engage in glutamine metabolism that exceeds the requirement for protein and nucleotide synthesis. Proc. Natl. Acad. Sci. USA 104, 19 345–19 350.
Beyond aerobic glycolysis: transformed cells can engage in glutamine metabolism that exceeds the requirement for protein and nucleotide synthesis.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD1cXisVOjtQ%3D%3D&md5=2131666d8452e7b843ad7f668c6cce2aCAS |

Donohoe, D. R., and Bultman, S. J. (2012). Metaboloepigenetics: interrelationships between energy metabolism and epigenetic control of gene expression. J. Cell. Physiol. 227, 3169–3177.
Metaboloepigenetics: interrelationships between energy metabolism and epigenetic control of gene expression.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC38Xnt1Knt7c%3D&md5=33e555d3f5757df9d249357a1d849f01CAS | 22261928PubMed |

Ezashi, T., Das, P., and Roberts, R. M. (2005). Low O2 tensions and the prevention of differentiation of hES cells. Proc. Natl. Acad. Sci. USA 102, 4783–4788.
Low O2 tensions and the prevention of differentiation of hES cells.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD2MXjt1Ohsrs%3D&md5=b957d0a08efa34feda81a80e196dfc04CAS | 15772165PubMed |

Fernandes, T. G., Diogo, M. M., Fernandes-Platzgummer, A., da Silva, C. L., and Cabral, J. M. (2010a). Different stages of pluripotency determine distinct patterns of proliferation, metabolism and lineage commitment of embryonic stem cells under hypoxia. Stem Cell Res. 5, 76–89.
Different stages of pluripotency determine distinct patterns of proliferation, metabolism and lineage commitment of embryonic stem cells under hypoxia.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC3cXpsFenuro%3D&md5=bd859cd47ee3c62effd772a5d9dfd8fdCAS | 20537975PubMed |

Fernandes, T. G., Fernandes-Platzgummer, A. M., da Silva, C. L., Diogo, M. M., and Cabral, J. M. (2010b). Kinetic and metabolic analysis of mouse embryonic stem-cell expansion under serum-free conditions. Biotechnol. Lett. 32, 171–179.
Kinetic and metabolic analysis of mouse embryonic stem-cell expansion under serum-free conditions.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD1MXhsFaqtrbM&md5=ee452545237f3f938e3cf9e99295ef32CAS | 19705070PubMed |

Forristal, C. E., Wright, K. L., Hanley, N. A., Oreffo, R. O., and Houghton, F. D. (2010). Hypoxia-inducible factors regulate pluripotency and proliferation in human embryonic stem cells cultured at reduced oxygen tensions. Reproduction 139, 85–97.
Hypoxia-inducible factors regulate pluripotency and proliferation in human embryonic stem cells cultured at reduced oxygen tensions.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC3cXovVWmsg%3D%3D&md5=bb35406a0b96da7b91e60a3e0282a38bCAS | 19755485PubMed |

Forsyth, N. R., Musio, A., Vezzoni, P., Simpson, A. H., Noble, B. S., and McWhir, J. (2006). Physiologic oxygen enhances human embryonic stem-cell clonal recovery and reduces chromosomal abnormalities. Cloning Stem Cells 8, 16–23.
Physiologic oxygen enhances human embryonic stem-cell clonal recovery and reduces chromosomal abnormalities.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD28XivFWgs7Y%3D&md5=232a3e8bf317bc3f049be784046ac679CAS | 16571074PubMed |

Fox, C. J., Hammerman, P. S., and Thompson, C. B. (2005). Fuel feeds function: energy metabolism and the T-cell response. Nat. Rev. Immunol. 5, 844–852.
Fuel feeds function: energy metabolism and the T-cell response.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD2MXhtFKls7jO&md5=3f108775fd60e97bf82e2002bd6e8e13CAS | 16239903PubMed |

Fritz, V., and Fajas, L. (2010). Metabolism and proliferation share common regulatory pathways in cancer cells. Oncogene 29, 4369–4377.
Metabolism and proliferation share common regulatory pathways in cancer cells.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC3cXms1ynur0%3D&md5=742bce2535ee349a1e12923768779f28CAS | 20514019PubMed |

Gardner, D. K. (1998). Changes in requirements and utilization of nutrients during mammalian preimplantation embryo development and their significance in embryo culture. Theriogenology 49, 83–102.
Changes in requirements and utilization of nutrients during mammalian preimplantation embryo development and their significance in embryo culture.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaK1cXnsFCrtA%3D%3D&md5=165a9203efeb5c56f7274ce52617e9f5CAS | 10732123PubMed |

Gardner, D. K. (2011) Analysis of embryo metabolism and the metabolome to identify the most viable embryo within a cohort. In ‘Human Assisted Reproductive Technology’. (Eds D. K. Gardner, B. R. M. B. Rizk and T. Falcone) pp. 301–312. (Cambridge University Press: New York.)

Gardner, D. K., and Leese, H. J. (1990). Concentrations of nutrients in mouse oviduct fluid and their effects on embryo development and metabolism in vitro. J. Reprod. Fertil. 88, 361–368.
Concentrations of nutrients in mouse oviduct fluid and their effects on embryo development and metabolism in vitro.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaK3cXhsFCks7Y%3D&md5=1473e5b1bce7cfad5b09868085c858fcCAS | 2313649PubMed |

Gardner, D. K., and Wale, P. L. (2013). Analysis of metabolism to select viable human embryos. Fertil. Steril. 99, 1062–1072.
Analysis of metabolism to select viable human embryos.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC3sXnslyksQ%3D%3D&md5=4e02b832dffc9d7ca1e51a9db210de9bCAS | 23312219PubMed |

Gardner, D. K., Wale, P. L., Collins, R., and Lane, M. (2011). Glucose consumption of single post-compaction human embryos is predictive of embryo sex and live-birth outcome. Hum. Reprod. 26, 1981–1986.
Glucose consumption of single post-compaction human embryos is predictive of embryo sex and live-birth outcome.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC3MXptFCnsbw%3D&md5=80a59836ab1d4073baf95eec4ce6839eCAS | 21572086PubMed |

Gibbons, J., Hewitt, E., and Gardner, D. K. (2006). Effects of oxygen tension on the establishment and lactate dehydrogenase activity of murine embryonic stem cells. Cloning Stem Cells 8, 117–122.
Effects of oxygen tension on the establishment and lactate dehydrogenase activity of murine embryonic stem cells.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD28XlvVGmu70%3D&md5=5cc21b21506a3fe09c0527de67f40e65CAS | 16776603PubMed |

Harvey, A. J., Rathjen, J., and Gardner, D. K. (2013) The metabolic framework of pluripotent stem cells and potential mechanisms of regulation. In ‘Stem Cells in Reproductive Medicine.’ 3rd edn. (Eds C. Simon, A. Pellicer and R. Reijo-Pera.) (Cambridge University Press: Cambridge.) (In press.)

Houghton, F. D., Hawkhead, J. A., Humpherson, P. G., Hogg, J. E., Balen, A. H., Rutherford, A. J., and Leese, H. J. (2002). Non-invasive amino-acid turnover predicts human embryo developmental capacity. Hum. Reprod. 17, 999–1005.
Non-invasive amino-acid turnover predicts human embryo developmental capacity.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD38Xjs12isLg%3D&md5=c34e3a44a2da666ffd84059f2d0a6593CAS | 11925397PubMed |

Hughes, J. N., Dodge, N., Rathjen, P. D., and Rathjen, J. (2009). A novel role for gamma-secretase in the formation of primitive streak-like intermediates from ES cells in culture. Stem Cells 27, 2941–2951.
| 1:CAS:528:DC%2BC3cXhsVCqtr0%3D&md5=9fcd33f4ffcb91349ecf52c85c4d1586CAS | 19750540PubMed |

Kapinas, K., Grandy, R., Ghule, P., Medina, R., Becker, K., Pardee, A., Zaidi, S. K., Lian, J., Stein, J., van Wijnen, A., and Stein, G. (2013). The abbreviated pluripotent cell cycle. J. Cell. Physiol. 228, 9–20.
The abbreviated pluripotent cell cycle.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC38XhsVKhu7jF&md5=7d159f711d1075288a094d391796df64CAS | 22552993PubMed |

Khosla, S., Dean, W., Reik, W., and Feil, R. (2001). Culture of preimplantation embryos and its long-term effects on gene expression and phenotype. Hum. Reprod. Update 7, 419–427.
Culture of preimplantation embryos and its long-term effects on gene expression and phenotype.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD3MXlvVKjtLo%3D&md5=7477729fd89d54d77cc1b93212a2eca4CAS | 11476355PubMed |

Kim, E. (2009). Mechanisms of amino-acid sensing in mTOR signalling pathway. Nutr. Res. Pract. 3, 64–71.
Mechanisms of amino-acid sensing in mTOR signalling pathway.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD1MXkvFegtr0%3D&md5=28b431b8edc6a0be516f124c969bd475CAS | 20016704PubMed |

Kobayashi, M., Takada, T., Takahashi, K., Noda, Y., and Torii, R. (2008). BMP4 induces primitive endoderm but not trophectoderm in monkey embryonic stem cells. Cloning Stem Cells 10, 495–502.
BMP4 induces primitive endoderm but not trophectoderm in monkey embryonic stem cells.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD1cXhsVGhtbjF&md5=fcde3c8883684c19976f8cae8f4790c8CAS | 18823266PubMed |

Kondoh, H., Lleonart, M. E., Nakashima, Y., Yokode, M., Tanaka, M., Bernard, D., Gil, J., and Beach, D. (2007). A high glycolytic flux supports the proliferative potential of murine embryonic stem cells. Antioxid. Redox Signal. 9, 293–299.
A high glycolytic flux supports the proliferative potential of murine embryonic stem cells.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD2sXhtlKlsLw%3D&md5=107701b959d28b66584c1ec2193f7504CAS | 17184172PubMed |

Lane, M., and Gardner, D. K. (1996). Selection of viable mouse blastocysts prior to transfer using a metabolic criterion. Hum. Reprod. 11, 1975–1978.
Selection of viable mouse blastocysts prior to transfer using a metabolic criterion.Crossref | GoogleScholarGoogle Scholar | 1:STN:280:DyaK2s%2FnvFensA%3D%3D&md5=ea27d4a2b68948f9e0615d4dc3dafbb6CAS | 8921074PubMed |

Lane, M., and Gardner, D. K. (2005). Understanding cellular disruptions during early embryo development that perturb viability and fetal development. Reprod. Fertil. Dev. 17, 371–378.
Understanding cellular disruptions during early embryo development that perturb viability and fetal development.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD2MXjt12nt7c%3D&md5=0edbf0593ecb2d0f8440d4284af7cf24CAS | 15745645PubMed |

López-Lázaro, M. (2008). The warburg effect: why and how do cancer cells activate glycolysis in the presence of oxygen? Anticancer. Agents Med. Chem. 8, 305–312.
The warburg effect: why and how do cancer cells activate glycolysis in the presence of oxygen?Crossref | GoogleScholarGoogle Scholar | 18393789PubMed |

Ludwig, T. E., Bergendahl, V., Levenstein, M. E., Yu, J., Probasco, M. D., and Thomson, J. A. (2006a). Feeder-independent culture of human embryonic stem cells. Nat. Methods 3, 637–646.
Feeder-independent culture of human embryonic stem cells.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD28XntFCgtb4%3D&md5=7d13e7c1da718910b690f4a8051c4eeeCAS | 16862139PubMed |

Ludwig, T. E., Levenstein, M. E., Jones, J. M., Berggren, W. T., Mitchen, E. R., Frane, J. L., Crandall, L. J., Daigh, C. A., Conard, K. R., Piekarczyk, M. S., Llanas, R. A., and Thomson, J. A. (2006b). Derivation of human embryonic stem cells in defined conditions. Nat. Biotechnol. 24, 185–187.
Derivation of human embryonic stem cells in defined conditions.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD28XhtFGqsrg%3D&md5=b0fb4d5337011941270825e1cdd02e5fCAS | 16388305PubMed |

Marks, H., Kalkan, T., Menafra, R., Denissov, S., Jones, K., Hofemeister, H., Nichols, J., Kranz, A., Stewart, A. F., Smith, A., and Stunnenberg, H. G. (2012). The transcriptional and epigenomic foundations of ground-state pluripotency. Cell 149, 590–604.
The transcriptional and epigenomic foundations of ground-state pluripotency.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC38Xmt1Gqtbw%3D&md5=e00cd2c6ef609a469bd33edb00762b2eCAS | 22541430PubMed |

Morgan, M. J., and Faik, P. (1981). Carbohydrate metabolism in cultured animal cells. Biosci. Rep. 1, 669–686.
Carbohydrate metabolism in cultured animal cells.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaL38Xit1Si&md5=d3ab31456383ab385be7a44bdc059a5bCAS | 6213274PubMed |

Oddens, B. L. B. (2006) ‘A decade of success in ART’. (Elsevier: Amsterdam.)

Pera, M. F., and Tam, P. P. (2010). Extrinsic regulation of pluripotent stem cells. Nature 465, 713–720.
Extrinsic regulation of pluripotent stem cells.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC3cXntF2nu70%3D&md5=4b61420a315c5570135ccb1627f94423CAS | 20535200PubMed |

Peura, T. T., Bosman, A., and Stojanov, T. (2007). Derivation of human embryonic stem-cell lines. Theriogenology 67, 32–42.
Derivation of human embryonic stem-cell lines.Crossref | GoogleScholarGoogle Scholar | 17074383PubMed |

Pinilla, J., Aledo, J. C., Cwiklinski, E., Hyde, R., Taylor, P. M., and Hundal, H. S. (2011). SNAT2 transceptor signalling via mTOR: a role in cell growth and proliferation? Front. Biosci. (Elite Ed) 3, 1289–1299.

Prasad, S. M., Czepiel, M., Cetinkaya, C., Smigielska, K., Weli, S. C., Lysdahl, H., Gabrielsen, A., Petersen, K., Ehlers, N., Fink, T., Minger, S. L., and Zachar, V. (2009). Continuous hypoxic culturing maintains activation of Notch and allows long-term propagation of human embryonic stem cells without spontaneous differentiation. Cell Prolif. 42, 63–74.
Continuous hypoxic culturing maintains activation of Notch and allows long-term propagation of human embryonic stem cells without spontaneous differentiation.Crossref | GoogleScholarGoogle Scholar | 1:STN:280:DC%2BD1M%2Fnt1SlsQ%3D%3D&md5=dd2c93c49fedbec90a3e260a638a1eb9CAS | 19143764PubMed |

Price, P. J., Goldsborough, M. D., and Tilkins, M. L. International Patent Application WO 98/30679. (1998). Embryonic stem-cell serum replacement. International Patent Application WO 98/30679.

Prigione, A., Fauler, B., Lurz, R., Lehrach, H., and Adjaye, J. (2010). The senescence-related mitochondrial/oxidative stress pathway is repressed in human induced pluripotent stem cells. Stem Cells 28, 721–733.
The senescence-related mitochondrial/oxidative stress pathway is repressed in human induced pluripotent stem cells.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC3cXms1yisL0%3D&md5=007ad00e9492da07a742b85db945fcbcCAS | 20201066PubMed |

Rathjen, J., and Rathjen, P. D. (2003). Lineage-specific differentiation of mouse ES cells: formation and differentiation of early primitive ectoderm-like (EPL) cells. Methods Enzymol. 365, 1–25.
Lineage-specific differentiation of mouse ES cells: formation and differentiation of early primitive ectoderm-like (EPL) cells.Crossref | GoogleScholarGoogle Scholar |

Reubinoff, B. E., Pera, M. F., Fong, C. Y., Trounson, A., and Bongso, A. (2000). Embryonic stem-cell lines from human blastocysts: somatic differentiation in vitro. Nat. Biotechnol. 18, 399–404.
Embryonic stem-cell lines from human blastocysts: somatic differentiation in vitro.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD3cXis1Gmt74%3D&md5=a6313256e9155ef170db9b9f03092483CAS | 10748519PubMed |

Sakkas, D., and Gardner, D. K. (2005). Noninvasive methods to assess embryo quality. Curr. Opin. Obstet. Gynecol. 17, 283–288.
Noninvasive methods to assess embryo quality.Crossref | GoogleScholarGoogle Scholar | 15870563PubMed |

Sancak, Y., Bar-Peled, L., Zoncu, R., Markhard, A. L., Nada, S., and Sabatini, D. M. (2010). Ragulator-Rag complex targets mTORC1 to the lysosomal surface and is necessary for its activation by amino acids. Cell 141, 290–303.
Ragulator-Rag complex targets mTORC1 to the lysosomal surface and is necessary for its activation by amino acids.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC3cXmtVWnsLk%3D&md5=7984528524b11846d0edc858317735bdCAS | 20381137PubMed |

Shodell, M., and Rubin, H. (1970). Studies on the nature of serum stimulation of proliferation in cell culture. In Vitro 6, 66–74.
Studies on the nature of serum stimulation of proliferation in cell culture.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaE3MXkvFGqtLs%3D&md5=d4298eccb50b6a5937684906b307ec41CAS | 5535596PubMed |

Simon, P. (2003). Q-Gene: processing quantitative real-time RT-PCR data. Bioinformatics 19, 1439–1440.
Q-Gene: processing quantitative real-time RT-PCR data.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD3sXlsl2lsb0%3D&md5=24f1ed93070594869acd61c5c2a37c8dCAS | 12874059PubMed |

Stead, E., White, J., Faast, R., Conn, S., Goldstone, S., Rathjen, J., Dhingra, U., Rathjen, P., Walker, D., and Dalton, S. (2002). Pluripotent cell division cycles are driven by ectopic Cdk2, cyclin A/E and E2F activities. Oncogene 21, 8320–8333.
Pluripotent cell division cycles are driven by ectopic Cdk2, cyclin A/E and E2F activities.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD38XovVGnu7Y%3D&md5=455e0289adbd1f5e2b1b700e1ec7a4e3CAS | 12447695PubMed |

Tan, B. S., Lonic, A., Morris, M. B., Rathjen, P. D., and Rathjen, J. (2011). The amino-acid transporter SNAT2 mediates l-proline-induced differentiation of ES cells. Am. J. Physiol. Cell Physiol. 300, C1270–C1279.
The amino-acid transporter SNAT2 mediates l-proline-induced differentiation of ES cells.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC3MXot1Cgtb4%3D&md5=2a1d09516d74146ef441fab58001cfdcCAS | 21346154PubMed |

Thompson, J. G., Gardner, D. K., Pugh, P. A., McMillan, W. H., and Tervit, H. R. (1995). Lamb birth weight is affected by culture system utilized during in vitro pre-elongation development of ovine embryos. Biol. Reprod. 53, 1385–1391.
Lamb birth weight is affected by culture system utilized during in vitro pre-elongation development of ovine embryos.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaK2MXpsVeisrs%3D&md5=ca25b748c413bc11c2c2a669d014b076CAS | 8562695PubMed |

Thomson, J. A., Itskovitz-Eldor, J., Shapiro, S. S., Waknitz, M. A., Swiergiel, J. J., Marshall, V. S., and Jones, J. M. (1998). Embryonic stem-cell lines derived from human blastocysts. Science 282, 1145–1147.
Embryonic stem-cell lines derived from human blastocysts.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaK1cXntleisLg%3D&md5=10226bdf182a21e8fa65b20486124fe9CAS | 9804556PubMed |

Varum, S., Rodrigues, A. S., Moura, M. B., Momcilovic, O., Easley, C. A. t., Ramalho-Santos, J., Van Houten, B., and Schatten, G. (2011). Energy metabolism in human pluripotent stem cells and their differentiated counterparts. PLoS ONE 6, e20914.
Energy metabolism in human pluripotent stem cells and their differentiated counterparts.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC3MXotVWgt7k%3D&md5=a06eef87419a4079bbd06c60e5e602abCAS | 21698063PubMed |

Wale, P. L., and Gardner, D. K. (2012). Oxygen regulates amino-acid turnover and carbohydrate uptake during the preimplantation period of mouse embryo development. Biol. Reprod. 87, 24.
Oxygen regulates amino-acid turnover and carbohydrate uptake during the preimplantation period of mouse embryo development.Crossref | GoogleScholarGoogle Scholar | 22553221PubMed |

Wang, J., Alexander, P., Wu, L., Hammer, R., Cleaver, O., and McKnight, S. L. (2009). Dependence of mouse embryonic stem cells on threonine catabolism. Science 325, 435–439.
Dependence of mouse embryonic stem cells on threonine catabolism.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD1MXovVCgtLY%3D&md5=b036e2bb42fefee245703720e33f5e10CAS | 19589965PubMed |

Warburg, O. (1956). On the origin of cancer cells. Science 123, 309–314.
On the origin of cancer cells.Crossref | GoogleScholarGoogle Scholar | 1:STN:280:DyaG28%2FltV2ktQ%3D%3D&md5=d0b8a696fe9510e8c0d88d904d3bb342CAS | 13298683PubMed |

Washington, J. M., Rathjen, J., Felquer, F., Lonic, A., Bettess, M. D., Hamra, N., Semendric, L., Tan, B. S., Lake, J. A., Keough, R. A., Morris, M. B., and Rathjen, P. D. (2010). L-proline induces differentiation of ES cells: a novel role for an amino acid in the regulation of pluripotent cells in culture. Am J Physiol Cell Physiol , .
L-proline induces differentiation of ES cells: a novel role for an amino acid in the regulation of pluripotent cells in culture.Crossref | GoogleScholarGoogle Scholar | 20164384PubMed |

Weinberg, F., and Chandel, N. S. (2009). Mitochondrial metabolism and cancer. Ann. N. Y. Acad. Sci. 1177, 66–73.
| 1:CAS:528:DC%2BD1MXhsFWksr7P&md5=ed61fc6dd40e4abe9a3c17b6dbcce971CAS | 19845608PubMed |

Yoshida, Y., Takahashi, K., Okita, K., Ichisaka, T., and Yamanaka, S. (2009). Hypoxia enhances the generation of induced pluripotent stem cells. Cell Stem Cell 5, 237–241.
Hypoxia enhances the generation of induced pluripotent stem cells.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD1MXhsVCiurnI&md5=d4af875d5fa150baa6820428e2f873d7CAS | 19716359PubMed |

Zachar, V., Prasad, S. M., Weli, S. C., Gabrielsen, A., Petersen, K., Petersen, M. B., and Fink, T. (2010). The effect of human embryonic stem cells (hESCs) long-term normoxic and hypoxic cultures on the maintenance of pluripotency. In Vitro Cell. Dev. Biol. Anim. 46, 276–283.
The effect of human embryonic stem cells (hESCs) long-term normoxic and hypoxic cultures on the maintenance of pluripotency.Crossref | GoogleScholarGoogle Scholar | 20177991PubMed |

Zhang, J., Khvorostov, I., Hong, J. S., Oktay, Y., Vergnes, L., Nuebel, E., Wahjudi, P. N., Setoguchi, K., Wang, G., Do, A., Jung, H. J., McCaffery, J. M., Kurland, I. J., Reue, K., Lee, W. N., Koehler, C. M., and Teitell, M. A. (2011). UCP2 regulates energy metabolism and differentiation potential of human pluripotent stem cells. EMBO J. 30, 4860–4873.
UCP2 regulates energy metabolism and differentiation potential of human pluripotent stem cells.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC3MXhsVOitrvO&md5=8905f9a1e47ac6de2ac5b1de54e3d107CAS | 22085932PubMed |