Leach Richard E, Kilburn Brian A, Petkova Anelia, Romero Roberto, Armant D Randall
Department of Obstetrics and Gynecology, University of Illinois School of Medicine, Chicago, IL, USA.
Am J Obstet Gynecol. 2008 Apr;198(4):471.e1-7; discussion 471.e7-8. doi: 10.1016/j.ajog.2008.01.009.
The antiapoptotic action of heparin-binding epidermal growth factor (HBEGF)-like growth factor and its regulation by O(2) constitutes a key factor for trophoblast survival. The hypothesis that cytotrophoblast survival is compromised by exposure to hypoxia-reoxygenation (H/R) injury, which may contribute to preeclampsia and some missed abortions, prompted us to investigate HBEGF regulation and its role as a survival factor during H/R in cytotrophoblast cells.
A transformed human first-trimester cytotrophoblast cell line HTR-8/SVneo was exposed to H/R (2% O(2) followed by 20% O(2)) and assessed for HBEGF expression and cell death.
Cellular HBEGF declined significantly within 30 minutes of reoxygenation after culture at 2% O(2). H/R significantly reduced proliferation and increased cell death when compared with trophoblast cells cultured continuously at 2% or 20% O(2). Restoration of cell survival also was achieved by adding recombinant HBEGF during reoxygenation. HBEGF inhibited apoptosis through its binding to either human epidermal receptor (HER)-1 or HER4, its cognate receptors.
These results provide evidence that cytotrophoblast exposure to H/R induces apoptosis and decreased cell proliferation. HBEGF accumulation is diminished under these conditions, whereas restoration of HBEGF signaling improves trophoblast survival.
肝素结合表皮生长因子(HBEGF)样生长因子的抗凋亡作用及其受氧调节情况是滋养层细胞存活的关键因素。细胞滋养层细胞暴露于缺氧复氧(H/R)损伤会影响其存活,这可能与子痫前期和一些稽留流产有关,这一假说促使我们研究H/R过程中细胞滋养层细胞内HBEGF的调节情况及其作为存活因子的作用。
将人早孕细胞滋养层细胞系HTR-8/SVneo暴露于H/R(先在2%氧气条件下培养,后在20%氧气条件下培养),并评估HBEGF表达和细胞死亡情况。
在2%氧气条件下培养后复氧30分钟内,细胞内HBEGF显著下降。与在2%或20%氧气条件下持续培养的滋养层细胞相比,H/R显著降低了细胞增殖并增加了细胞死亡。在复氧期间添加重组HBEGF也实现了细胞存活的恢复。HBEGF通过与人表皮受体(HER)-1或其同源受体HER4结合来抑制细胞凋亡。
这些结果表明,细胞滋养层细胞暴露于H/R会诱导细胞凋亡并降低细胞增殖。在这些条件下,HBEGF的积累减少,而恢复HBEGF信号传导可提高滋养层细胞的存活率。