Journal of Molecular Histology

, Volume 50, Issue 3, pp 273–283 | Cite as

Role of mTOR complex in IGF-1 induced neural differentiation of DPSCs

  • Dan Huang
  • Shuling Shen
  • Ming Cai
  • Lin Jin
  • Jun Lu
  • Ke Xu
  • Jinlong Zhang
  • Guijuan Feng
  • Yingzi Hu
  • Ke ZhengEmail author
  • Xingmei FengEmail author
Original Paper


Recent studies have demonstrated that IGF-1 modulates the pluripotent differentiation of dental pulp stem cells (DPSCs). Although mTOR pathway activation has been showed as responsible for IGF-1 induced pluripotent differentiation, the mechanism that the IGF-1–mTOR pathway induces the neural differentiation of DPSCs is still unclear. In our research, we have demonstrated that 0–10 ng/mL IGF-1 had no obvious effect on the proliferation of DPSCs, but IGF-1 nonetheless enhances the neural differentiation of DPSCs in a dose-dependent manner. Simultaneously, we found that phosphorylated mTOR was up-regulated, which indicated the involvement of mTOR in the process. Rapamycin, an inhibitor of mTOR activity, can reverse the effect of DPSCs stimulated by IGF-1. Next, we studied the role of mTORC1 and mTORC2, two known mTOR complexes, in the neural differentiation of DPSCs. We found that inhibition of mTORC1 can severely restricts the neural differentiation of DPSCs. However, inhibition of mTORC2 has the opposite effect. This latter effect disappears when both rictor and mTOR are inhibited, showing that the mTORC2 effect is mTORC1 dependent. This study has expanded the role of mTOR in DPSCs neural differentiation regulated by IGF-1.


Dental pulp stem cells (DPSCs) Insulin-like growth factor 1 (IGF-1) mTOR signaling Neural differentiation 



This study was supported by Chinese National Natural Science Foundation of China Grant (Nos. 81500809, 81501076).


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Copyright information

© Springer Nature B.V. 2019

Authors and Affiliations

  • Dan Huang
    • 1
  • Shuling Shen
    • 2
  • Ming Cai
    • 3
  • Lin Jin
    • 4
  • Jun Lu
    • 1
  • Ke Xu
    • 1
  • Jinlong Zhang
    • 5
  • Guijuan Feng
    • 1
  • Yingzi Hu
    • 6
  • Ke Zheng
    • 7
    Email author
  • Xingmei Feng
    • 1
    Email author
  1. 1.Department of StomatologyAffiliated Hospital of Nantong UniversityNantongChina
  2. 2.Department of StomatologyAffiliated Hospital of Jiangsu UniversityZhenjiangChina
  3. 3.General Surgery DepartmentThe Second Affiliated Hospital of Nantong UniversityNantongChina
  4. 4.Department of EndodonticsNantong Stomatological HospitalNantongChina
  5. 5.Department of Spine SurgeryThe Second Affiliated Hospital of Nantong UniversityNantongChina
  6. 6.Medical College of Nantong UniversityNantongChina
  7. 7.Department of StomatologyWuxi No.2 People’s HospitalWuxiChina

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