Effect Of Adipose-Derived Stem Cells On Proliferation And Dedifferentiation Of Schwann Cells In The Early Stage Of Wallerian Degeneration

Objective: To investigate the effect of adipose-derived stem cells(ADSCs)on proliferation and dedifferentiation of Schwann cells(SCs)at early stage of Wallerian degeneration by constructing in vitro rat model.Methods: After extracting subcutaneous adipose tissue from the groin of SD rats under sterile conditions,adipose-derived stem cells were isolated and cultured in vitro,and the morphology and growth status were observed by inverted microscope.Their surface markers were examined by flow cytometry.Wallerian degeneration in vitro rat models were constructed by the use of sciatic nerve and randomly divided into experimental and control group.In the experimental group,sciatic nerve and adipose-derived stem cells were co-cultured in a non-contact way,while sciatic nerve were cultured alone in the control group.Real time PCR was conducted to detect the m RNA expression of p75 NTR and MPZ at different time points(0h,24 h,72h).The protein expression of p75 NTR and MPZ were detected after 72 h in vitro culture by Western blot.The proliferation and apoptosis of Schwann cells in both groups were examined at different time points(24h,48 h,72h)by immunohistochemical staining(IHC)and Tunel method,respectively.Results:Flow cytometry showed that CD90 and CD105 were highly expressed in the adipose-derived stem cells,but CD34 was rarely expressed.After 72 h culture,the m RNA expression of the dedifferentiation marker p75 NTR was greatly increased,and a more significant growth trend was examined in the experimental group(P<0.05).And the m RNA expression of the differentiation marker MPZ was gradually reduced with a more obvious decreasing tendency in the experimental group(P < 0.001).In addition,compared with the control group,the protein expression of p75 NTR was significantlyhigher after 72 h co-culture(P<0.05),and the expression of MPZ was significantly lower(P<0.001).Besides,the expression of Ki67 in the experimental group was significantly higher than the control group by IHC,and the apoptosis rate was lower in the experimental group by Tunel method.Conclusion: Adipose-derived stem cells might promote the proliferation and dedifferentiation of Schwann cells of Wallerian degeneration,and also inhibit their apoptosis.