Cyclic Mechanical Stretch Ameliorates the Degeneration of Nucleus Pulposus Cells through Promoting the ITGA2/PI3K/AKT Signaling Pathway

Figure 6

Involvement of the PI3K-AKT pathway in the cyclic mechanical stretch-mediated effects on NP cells. (a) Cyclic mechanical stretch promoted the PI3K-AKT pathway in NP cells. The protein expression of ITGA2, p-AKT, AKT, and COL2A1 was upregulated in the tensile stress group. (b) Inhibition of the PI3K-AKT pathway. Western blot analyses showing downregulation of ITGA2 and AKT protein expression in NP cells transfected with siRNA-ITGA2/AKT. COL2A1 protein expression was remarkably decreased. Cyclic mechanical stretch did not significantly affect the expression of ITGA2, AKT, and COL2A1 in NP cells transfected with siRNA-ITGA2/AKT. (c) Downregulation of the PI3K-AKT pathway significantly inhibited the proliferation of NP cells. Cyclic mechanical stretch did not significantly affect the proliferation of NP cells when the PI3K-AKT pathway was inhibited.

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