The Effect Of CLDN 15 On Early Wallerian Degeneration After Rat Sciatic Nerve Injury

Objective In the process of peripheral nerve repair, Schwann cells(SCs) secrete a variety of cytokines involved in the regeneration process, which provides good micro-environment for nerve regeneration. Based on the results of gene chip and protein chip analysis, claudin 15(CLDN 15)plays a central role in signal transduction network after rat sciatic nerve injury. This experiment aims to explore the effect of CLDN 15 on the function of SCs during early Wallerian degeneration, and explore the molecular mechanism of its regulation pathways for nerve regeneration,thus providing more theoretical basis for peripheral nerve repair.Methods1. Construction of rat sciatic nerve transection injury models;2. Immunohistochemistry(IHC) and Immunocytochemistry(ICC)analying the location of CLDN 15 and S100B;3. CLDN 15-si RNA and overexpression plasmid transfection into SCs in vitro;4. Real- time PCR analysis;5. Western Blot analysis;6. Ed U proliferation assay, Annexin V apoptosis assay, and Transwell migration assay;7. Statistical analysis.Results:1. IHC and ICC analysed the co-location of CLDN 15 and S100 B in SCs;2. The expression of CLDN 15 increased during eraly WD after rat sciatic nerve injury;3. SCs proliferation increased and apoptosis decreased after the transfection of CLDN 15-si RNA;4. SCs proliferation decreased and apoptosis increased after the transfection of CLDN 15 overexpression plasmid;5. After CLDN 15 interference and overexpression, genes associated to nerve regenration differentially expressed;6. C-jun differentially expressed after CLDN 15 interference and overexpression, but c-fos and PKC? changed only after CLDN 15 overexpression.Conclusions1. CLDN 15 expressed on the SCs membrane;2. CLDN 15 inhibits the proliferation of SCs and promotes the apoptosis of SCs, but has no insignificant influence on the migration of SCs;3. CLDN 15 may regulate SCs by c-jun pathway and it may also affect C-fos and PKC? pathways.