1. ES Micro-Environment Enhances Stemness and Inhibits Apoptosis in Human Limbal Stem Cells via the Maintenance of Telomerase Activity
- Author
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Hucheng Duan, Chaoyang Li, Pengxia Wan, Zhiping Liu, Zhichong Wang, Chenjing Zhou, Ying Liu, Zheqian Huang, Jin Zhou, Bowei Tan, Bishan Tian, and Qiang Zhou
- Subjects
Telomerase ,Cellular differentiation ,lcsh:Medicine ,Apoptosis ,Biology ,Limbus Corneae ,Models, Biological ,Colony-Forming Units Assay ,Mice ,Molecular Cell Biology ,Akt Signaling Cascade ,Animals ,Humans ,Telomerase reverse transcriptase ,lcsh:Science ,Wnt Signaling Pathway ,Embryonic Stem Cells ,WNT Signaling Cascade ,Cells, Cultured ,Cell Proliferation ,Multidisciplinary ,Akt/PKB signaling pathway ,Stem Cells ,lcsh:R ,Wnt signaling pathway ,Cell Differentiation ,Embryonic stem cell ,Signaling Cascades ,Cell biology ,Ophthalmology ,Cellular Microenvironment ,Culture Media, Conditioned ,Focal Adhesion Protein-Tyrosine Kinases ,Corneal Disorders ,Medicine ,lcsh:Q ,RNA Interference ,sense organs ,Stem cell ,Cellular Types ,Research Article ,Developmental Biology ,Signal Transduction - Abstract
Our previous work had found that telomerase rejuvenated in the cytoplasm of corneal epithelial cells cultured in embryonic stem cell-conditioned medium, the functional properties of stem-like corneal epithelial cells can be enhanced by co-culturing with embryonic stem cells (ESCs) via activation of the integrinβ1-FAK-PI3K/Akt signaling pathway. The goal of this study was to explore the potential molecular mechanisms of the ES micro-environment that enhance the stem cell-like phenotype and inhibit apoptosis in human limbal stem cells (LSC). The LSC were cultured in different media, either CnT-20 medium or CnT-20 +20% ES culture supernatant (ESC-CM). We observed that LSC cultured in ESC-CM had an increased proliferative capacity, greater serial passage capacity, higher colony-forming efficiency (CFE) and higher levels of stem cell-associated marker than those cultured in CnT-20. Compared with CnT-20, ESC-CM enhanced the undifferentiated status and inhibited apoptosis in the LSC by promoting the maintenance of telomerase activity, which could reduce the generation of reactive oxygen species (ROS), maintain the membrane potential (Δψm) at higher levels and reduce the expression of the p21 protein. Our findings indicated that ESC-CM system induced LSC to maintain a stem cell phenotype and inhibit the process of apoptosis. These effects might partially be achieved via the telomerase-p21-mitochondrial axis and the activation of the FAK/Wnt signaling pathways. This study may have high impact and clinic implication on the expansion of LSC in regenerative medicine, especially for ocular surface reconstruction.
- Published
- 2013