PI3-K/Akt/JNK/NF-魏B is essential for MMP-9 expression and outgrowth in human limbal epithelial cells on intact amniotic membrane
- 作者：Ching-Yi Chenga ; Hsi-Lung Hsiehb ; Li-Der Hsiaoc ; Chuen-Mao Yangc ; chuenmao@mail.cgu.edu.tw
- 关键词：MMP-9 ; matrix metalloproteinase-9 ; SCs ; stem cells ; LSCD ; limbal stem cell deficiency ; ECM ; extracellular matrix ; PI3-K ; phosphatidylinositol 3-kinase ; ERK1/2 ; extracellular signal-regulated kinase 1/2 ; JNKs ; c-Jun N-terminal kinases
- 刊名：Stem Cell Research
- 出版年：2012
- 期刊代码：P20_18735061
- 类别：bio
- 出版时间：July, 2012
- 卷：9
- 期：1
- 页码：9-23
- 文件大小：1926 K
摘要
Matrix metalloproteinase-9 (MMP-9) plays an important role in the outgrowth of expanded human limbal epithelial cells on intact amniotic membranes (AM). The mechanisms of MMP-9 expression and cell outgrowth remain unknown. Here, we demonstrated that MMP-9 is preferentially expressed at the leading edge of limbal epithelial outgrowth. Treatment with the inhibitors of PI3-K (LY294002), Akt (SH-5), MEK1/2 (U0126), and JNK1/2 (SP600125) attenuated the outgrowth area, indicating that PI3-K/Akt, p42/p44 MAPK, and JNK1/2 are involved in the outgrowth of intact AM-expanded limbal epithelial cells. However, MMP-9 expression at both transcriptional and translational levels was attenuated by treatment with SP600125, LY294002, or SH-5, not by U0126 and SB202190, suggesting that JNK1/2 and PI3-K/Akt participate in MMP-9 expression. Moreover, NF-魏B phosphorylation and nuclear translocation was especially noted at the leading edge, which was attenuated by treatment with SP600125 or LY294002. Helenalin, a selective NF-魏B inhibitor, reduced both the limbal epithelial outgrowth and MMP-9 expression. Finally, the data reveal that PI3-K/Akt is an upstream component of the JNK1/2 pathway in MMP-9 expression. Thus, both MAPKs and PI3-K/Akt are required for limbal epithelial outgrowth on intact AM, only the PI3-K/Akt/JNK is essential for MMP-9 expression mediated through activation of transcriptional factor NF-魏B in this model.