Physiological roles of insulin-like growth factor binding protein 3 in mouse endometrium

IGFBP3抑制IGF1诱导的子宫内膜细胞增殖。雌二醇（E2）和TGFα可降低子宫内膜间质细胞中IGFBP3 mRNA的表达，MMP 3和激肽释放酶（Klk）1可降解IGFBP3。TGFα可增加MMP 3mRNA的表达，E2可增加Klk 1mRNA的表达。MMP 3和Klk 1的产生增加降低了子宫内膜中的IGFBP3水平，导致游离IGF1水平增加。E2促进子宫内膜间质细胞分泌IGF1，E2和TGFα降低IGFBP3水平，从而促进子宫内膜细胞增殖。

IGFBP3 inhibited IGF1-induced proliferation of endometrial cells. Igfbp3 mRNA expression in the endometrial stromal cells was decreased by estradiol-17β(E2) and TGFα.MMP3 and Kallikrein (Klk) 1 degrade IGFBP3. Mmp3mRNA expression was increased by TGFα, and Klk1mRNA expression was by E2. Enhanced production of MMP3 and Klk1 decrease IGFBP3 levels in the endometrium, resulting in the increase in free IGF1 levels. E2 increased Igf1mRNA expression.These findings provide the possible regulatory mechanism of endometrialstromal cell proliferation that E2 stimulates IGF1 production, while E2 and TGFαdecrease IGFBP3 level, leading to the stimulation of endometrial cell proliferation.