Sanders Kaitlyn, Jung Jin Hyuk, Loeken Mary R
Section on Islet Cell and Regenerative Biology, Joslin Diabetes Center, Boston, Massachusetts.
Birth Defects Res A Clin Mol Teratol. 2014 Aug;100(8):584-91. doi: 10.1002/bdra.23281. Epub 2014 Aug 13.
Neural tube defects (NTDs) are significantly increased by maternal diabetes. Embryonic stem cells (ESC) that can differentiate into neuroepithelium and can sense supraphysiological glucose concentrations would be very valuable to simulate the effects of maternal diabetes on molecular and cellular processes during neural tube formation.
LG-ESC, a recently established ESC line that expresses the glucose transporter, Scl2a2, and is sensitive to elevated glucose concentrations, were grown for up to 8 days in a three-dimensional culture to form neural cysts. We tested whether high glucose media inhibits expression of Pax3, a gene that is required for neural tube closure and whose expression is inhibited in embryos of diabetic mice, and inhibits formation of neural cysts.
Pax3 expression was detected after 4 days of culture and increased with time. Pax3 expression was inhibited by high glucose media, but not if cells had been cultured in low glucose media for the first 4 days of culture. Pax7, which is also expressed in dorsal neural tube, was not detected. Pax6, which is expressed in the ventral neural tube, was detected only after 8 days of culture, but was not inhibited by high glucose. High glucose media did not inhibit formation of neural cysts.
LG-ESC can be used as a model of embryonic exposure to a diabetic environment during neural tube development. While high glucose exposure inhibits expression of a gene required for neural tube closure, it may not inhibit all of the processes involved in formation of a neural tube-like structure.
母体糖尿病会显著增加神经管缺陷(NTDs)的发生风险。能够分化为神经上皮且能感知超生理浓度葡萄糖的胚胎干细胞(ESC),对于模拟母体糖尿病对神经管形成过程中分子和细胞过程的影响具有重要价值。
LG-ESC是最近建立的一种胚胎干细胞系,表达葡萄糖转运蛋白Scl2a2,对升高的葡萄糖浓度敏感。将其在三维培养中培养长达8天以形成神经囊肿。我们测试了高糖培养基是否会抑制Pax3的表达(Pax3是神经管闭合所需的基因,其表达在糖尿病小鼠胚胎中受到抑制),以及是否会抑制神经囊肿的形成。
培养4天后检测到Pax3表达,且随时间增加。高糖培养基抑制Pax3表达,但如果细胞在培养的前4天在低糖培养基中培养,则不会受到抑制。未检测到同样在背侧神经管表达的Pax7。在腹侧神经管表达的Pax6仅在培养8天后检测到,但不受高糖抑制。高糖培养基不抑制神经囊肿的形成。
LG-ESC可作为神经管发育过程中胚胎暴露于糖尿病环境的模型。虽然高糖暴露会抑制神经管闭合所需基因的表达,但可能不会抑制神经管样结构形成所涉及的所有过程。