[Frontiers In Bioscience, Landmark, 23, 1848-1863, June1, 2018]

Differential effects of the PI3K/AKT pathway on antler stem cells for generation and regeneration of antlers in vitro

Zhen Liu1,2, Hai-ping Zhao1,2, Da-tao Wang1,2, Chris McMahon3, Chun-yi Li1,2

1Institute of Special Wild Economic Animals and Plants, Chinese Academy of Agricultural Sciences, Changchun, Jilin, P. R. China, 2State Key Laboratory for Molecular Biology of Special Economic Animals, Jilin, P. R. China, 3AgResearch Ltd, Ruakura Research Centre, Private bag 3123, Hamilton 3240, New Zealand


1. Abstract
2. Introduction
3. Materials and methods
3.1. Tissue collection and cell culture
3.2. MTT assay
3.3. Cytoskeleton staining
3.4. Cell cycle determination
3.5. Cellular adhesion testing
3.6. Tube formation assay
3.7. Quantitative PCR
3.8. Western blot analysis
4. Results
4.1. Effects of LY294002 on four basic parameters of the ASCs
4.1.1. Proliferation
4.1.2. Cytoskeleton
4.1.3. Cell cycle
4.1.4. Adhesion
4.2. Effects of the AP or PP conditioned medium on tube formation
4.3. Expression of VEGF-B mRNA in the AP or PP cells
4.4. LY294002 induces a PI3K-dependent decrease of p-AKT
5. Discussion
6. Acknowledgements
7. References


Understanding the role of the PI3K/AKT pathway in regulating basic antler stem cell parameters and angiogenesis may provide an insight into the mechanisms underlying mammalian appendage development. The present study took multiple approaches in vitro to investigate the effects of the PI3K/AKT pathway on antler stem cells. By addition of LY294002, proliferation rate of the antlerogenic periosteum (AP) cells was decreased significantly (p<0.01), while the proliferation rate of the pedicle periosteum (PP) cells decreased to a lesser extent; the cytoskeleton of the AP cells was essentially collapsed; and the PP cells significantly shrunken. By addition of LY294002 or KU-0063794, formation of networking tubular structures from HUVECs in the AP or PP cell conditioned medium was significantly inhibited; whereas, expression level of VEGF-B mRNA in the AP or PP cells was decreased by the former, and increased by the latter significantly. Therefore, the results suggest that the PI3K/AKT pathway is involved in proliferation and differentiation of the AP and the PP cells, and plays a more important role in the former than in the latter.


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Abbreviations: AP: antlerogenic periosteum; PP: pedicle periosteum; ASCs: antler stem cells; FP: facial periosteum; VEGF: Vascular endothelial growth factor; HUVECs: human umbilical vein endothelial cells

Key Words: PI3K/AKT pathway; Antler Stem Cell; Antler generation; Angiogenesis; VEGF-B

Send correspondence to: Chunyi Li, State Key Lab for Molecular Biology of Special Economic Animals, 4899 Juye Street, Changchun City, Jilin, China, Tel: 0431-81919500, Fax: 0431-81919800, E-mail: Chunyi.li@agresearch.co.nz