(2)母体由来パラクライン因子による卵成熟および胚発育の調節(<特集>第60回学術講演会要旨シンポジウム2「卵の発育・成熟・老化機構の解明と臨床応用」)
スポンサーリンク
概要
- 論文の詳細を見る
In mammals, rupture of ovarian follicles and final maturation of oocytes occur in response to stimulation by pituitaryderived luteinizing hormones (LH) that act on the somatic granulosa and theca cells surrounding the oocyte. Because LH interacts only with ovarian somatic cells, its potential regulation of oocyte functions is presumably mediated by local paracrine factors. Shortly after stimulation by the preovulatory surge of LH, oocytes arrested at the late prophase resume meiosis characterized by germinal vesicle (nuclear envelope) breakdown (GVBD), chromosome condensation, and extrusion of the first polar body in preparation for fertilization and early embryonic development. In addition to nuclear maturation exemplified by GVBD and extrusion of the first polar body to complete the first meiotic division, oocytes also undergo cytoplasmic maturation characterized by cytoplasmic changes essential for monospermic fertilization, processing of the sperm, and preparation for development to preimplantation embryos. Although the spermatozoon provides an essential element for embryo generation, the developmental fate of the embryo is principally dictated by the oocyte. Accumulating evidence indicates that a number of growth factors and cytokines act as paracrine and/or autocrine factors during early embryo development. In addition, developing early embryos produce growth factors that act in an autocrine manner to regulate their own growth and differentiation, or to serve as paracrine factors by regulating endometrial receptivity for blastocyst implantation. Apoptosis is an essential physiologic process used in almost all tissues to remove damaged or superfluous cells. However, early embryos are unique because no cell death is found up to the blastocyst stage during normal development. Recent studies have focused on the role of apoptosis on the degradation of preimplantation embryos during in vitro cultures. In the in vitro environment, apoptosis of early embryos has been attributed to the lack of maternal paracrine factors such as essential growth factors and cytokines released by maternal reproductive tracts. Here, we show novel maternal paracrine factors that regulate oocyte maturation and preimplantation embryo development and apoptosis. We performed DNA microarray analyses using ovaries following gonadotropin stimulation and identified candidate ligand-receptor pairs potentially involved in the process of oocyte maturation. Among ovarian genes, we selected the candidates based on the increased expression levels by the preovulatory LH surge and localization of ligands and receptors in ovarian somatic cells and oocytes or cumulus-oocyte complexes, respectively. Using in vitro and in vivo studies for oocyte nuclear and cytoplasmic maturation, we determined novel ovarian paracrine factors for induction of oocyte maturation. We also found novel paracrine factors that stimulate or inhibit early embryonic development and apoptosis based on the localization of ligand-receptor pairs in reproductive tracts and preimplantation embryos. Furthermore, we demonstrated molecular mechanisms of the paracrine factors to inhibit apoptosis by using antisense approach for gene down regulation in the embryos. In this meeting, I have shown brain derived neurotrophic factor, GnRH-I, transforming growth factor/survivin, as representative maternal paracrine factors for oocyte maturation, embryo development, and mechanism of apoptosis in embryos, respectively.
- 社団法人 日本産科婦人科学会の論文
- 2008-10-01
著者
関連論文
- 選択的単一胚移植(eSET)の当科における適応基準とその多胎妊娠予防効果の検討
- 母体由来の Survivin mRNA のマウス卵子および着床前期胚における発現様式
- 新規母体由来卵成熟・胚発育調節因子の同定 : Glial cell-line derived neurotrophic factor (GDNF)
- TNFによる着床前期胚のアポトーシス誘導と TGF alpha/Phosphatidylinositol 3-kinase 経路によるその抑制機構の解明
- 新規母体由来卵成熟因子の同定 : endothelin-1/EDNRA signaling system
- 平成17年度学術奨励賞受賞論文 卵巣由来Brain-Derived Neurotrophic Factor(BDNF)による卵成熟機構の解明
- マウス着床前期胚におけるHtrA2/Omiの発現とアポトーシスおよびフラグメンテーションへの関与に関する研究
- マウス着床前期胚における leptin の発育促進作用について
- 40歳以上の不妊症婦人における体外受精胚移植法の治療成績
- 着床前期胚の発育とその調節因子
- (2)母体由来パラクライン因子による卵成熟および胚発育の調節(第60回学術講演会要旨シンポジウム2「卵の発育・成熟・老化機構の解明と臨床応用」)
- 臨床経験 新規母体由来卵成熟・胚発育調節因子の同定--Glial cell-line derived neurotrophic factor(GDNF)