Mitochondria were first discovered in 1890, and in 1936 it was further discovered that they contain their own unique DNA. The most basic role of mitochondria is to control the energy supply for oxidative reactions in cells, so it is important for embryos Development, apoptosis and aging are all important.
The role of mitochondria in embryonic development
At the time of ovulation, the egg cell contains about 100,000 mitochondria, but these mitochondria are not structurally differentiated and the concentration of ATP produced is low. Until the early stage of the embryo, due to the demand for local energy, mitochondria are in the cell If this process is damaged, it will have a negative impact on the recombination and separation of chromosomes. The difference in mitochondria between different cells affects the difference in ATP content in the egg cell. Although it does not affect the ability of the egg to fertilize, it will. But it reflects the potential of subsequent embryonic development. Furthermore, we all know that mitochondrial health is very important to the embryo, and even if there are mitochondrial mutations outside the D-loop, it often leads to cytoplasmic factors. And the role of mitochondria and ATP in it on embryonic growth and development is obvious.
For the treatment of infertility, there are many factors that affect the development and implantation of human embryos. One of the main factors is maternal age. In particular, poor egg cytoplasm quality is considered to be the main cause, especially the neutrophils in the egg cytoplasm. Insufficient ATP efficiency caused by poor body function is an important factor. Cytoplasmic transfer has been shown in mouse experiments to increase ATP production in mouse cytoplasmic recipients, thus promoting embryonic development and implantation in some human patients. After IVF treatment, although various methods have been used to improve the quality of the embryos, it is still difficult to achieve success. For these patients, Cohen in the United States first published a breakthrough method in Lancet in 1997, which was to use egg cytoplasm. Transplantation is not difficult to treat these patients and is similar to ICSI. It is to microinject part of the egg cytoplasm that is considered healthy into the egg cells of infertile patients, using foreign cytoplasm and various factors in it. The injection, including mitochondria, improves the quality of cytoplasm to promote egg cell fertilization and division.
In the results of related experiments, mitochondria are considered to be the most important factor. However, due to Cohen's egg cytoplasm transfer technique, the transferred cytoplasm comes from the donor, so the genetic problems of mitochondrial DNA between different individuals are not possible. This has been questioned, so recently some researchers from Taiwan's Peking University Medical School have tried to isolate the mitochondria from the patient's own granulosa cells, and then injected them into the egg cytoplasm through microinjection to achieve the purpose of improving embryonic development and implantation. It has caused widespread discussion, but the number of mitochondria it can inject is limited, and whether the effects of different mitochondria between somatic cells and germ cells can complement each other, as well as the lack of control groups and animal experiments to prove its effectiveness, make this method difficult. Whether this treatment can really improve embryonic development has become the focus of discussion, which also shows the importance of mitochondria in the process of embryonic development.
In view of the fact that mitochondria have a great impact on embryonic development, fertilization, and even the future health and lifespan of the child through maternal inheritance after pregnancy, it is important to plan the activation of maternal mitochondria during the pregnancy preparation period. The most important thing.
