Peripheral nerve regeneration requires stepwise and well-organized establishment of microenvironment.Since local delivery of VEGF-A in peripheral nerve repair is expected to promote angiogenesis in the microenvironmen...Peripheral nerve regeneration requires stepwise and well-organized establishment of microenvironment.Since local delivery of VEGF-A in peripheral nerve repair is expected to promote angiogenesis in the microenvironment and Schwann cells(SCs)play critical role in nerve repair,combination of VEGF and Schwann cells may lead to efficient peripheral nerve regeneration.VEGF-A overexpressing Schwann cells were established and loaded into the inner wall of hydroxyethyl cellulose/soy protein isolate/polyaniline sponge(HSPS)conduits.When HSPS is mechanically distorted,it still has high durability of strain strength,thus,can accommodate unexpected strain of nerve tissues in motion.A 10 mm nerve defect rat model was used to test the repair performance of the HSPS-SC(VEGF)conduits,meanwhile the HSPS,HSPS-SC,HSPS-VEGF conduits and autografts were worked as controls.The immunofluorescent co-staining of GFP/VEGF-A,Ki67 and MBP showed that the VEGF-A overexpressing Schwann cells could promote the proliferation,migration and differentiation of Schwann cells as the VEGF-A was secreted from the VEGF-A overexpressing Schwann cells.The nerve repair performance of the multifunctional and flexible conduits was examined though rat behavioristics,electrophysiology,nerve innervation to gastrocnemius muscle(GM),toluidine blue(TB)staining,transmission electron microscopy(TEM)and NF200/S100 double staining in the regenerated nerve.The results displayed that the effects on the repair of peripheral nerves in HSPS-SC(VEGF)group was the best among the conduits groups and closed to autografts.HSPS-SC(VEGF)group exhibited notably increased CD31+endothelial cells and activation of VEGFR2/ERK signaling pathway in the regenerated nerve tissues,which probably contributed to the improved nerve regeneration.Altogether,the comprehensive strategy including VEGF overexpressing Schwann cells-mediated and HSPS conduit-guided peripheral nerve repair provides a new avenue for nerve tissue engineering.展开更多
基金This research was supported by grants from the Ministry of Ed- ucation (705001), National Basic Research Program of China (973 Program 2009CB941200), National Natural Science Foundation of China (30830061 and 30421004), and a 111 project to H Deng. We thank Dr Tak Wah Mak (University of Alberta, Canada) for kindly providing the Ptern mice, Dr Guoqiang Gu (Vanderbilt University, USA) for kindly providing the plasmid of Pdxl-Cre, and Dr C Wright (Vanderbilt University, USA) for the PDX1 antibody. We thank the Model Animal Research Center of Nanjing University for B6 129-Gt(ROSA)26Sor tm/Sho/J mice and the Research Center for Proteome Analysis for proteomics analysis. We thank Dr Matt Stremlau, Dr Hui Zhang, Jun Cai, Han Qin, Jian Li, Yan Shi, Haisheng Zhou, and Fei Ye for their critical reading of the manu- script. We also thank Wei Jiang, Yushan Guo, Jie Yang, Chengyan Wang, Hui Zhang, and other colleagues in our laboratory for providing technical assistance and advice during the experiments.
基金This work was supported by the National Natural Science Foundation of China(Grant No.:NSFC 81871493,81871503)the Medical Science Advancement Program(Clinical Medicine)of Wuhan University(Grant No.:TFLC2018002,2018003)。
文摘Peripheral nerve regeneration requires stepwise and well-organized establishment of microenvironment.Since local delivery of VEGF-A in peripheral nerve repair is expected to promote angiogenesis in the microenvironment and Schwann cells(SCs)play critical role in nerve repair,combination of VEGF and Schwann cells may lead to efficient peripheral nerve regeneration.VEGF-A overexpressing Schwann cells were established and loaded into the inner wall of hydroxyethyl cellulose/soy protein isolate/polyaniline sponge(HSPS)conduits.When HSPS is mechanically distorted,it still has high durability of strain strength,thus,can accommodate unexpected strain of nerve tissues in motion.A 10 mm nerve defect rat model was used to test the repair performance of the HSPS-SC(VEGF)conduits,meanwhile the HSPS,HSPS-SC,HSPS-VEGF conduits and autografts were worked as controls.The immunofluorescent co-staining of GFP/VEGF-A,Ki67 and MBP showed that the VEGF-A overexpressing Schwann cells could promote the proliferation,migration and differentiation of Schwann cells as the VEGF-A was secreted from the VEGF-A overexpressing Schwann cells.The nerve repair performance of the multifunctional and flexible conduits was examined though rat behavioristics,electrophysiology,nerve innervation to gastrocnemius muscle(GM),toluidine blue(TB)staining,transmission electron microscopy(TEM)and NF200/S100 double staining in the regenerated nerve.The results displayed that the effects on the repair of peripheral nerves in HSPS-SC(VEGF)group was the best among the conduits groups and closed to autografts.HSPS-SC(VEGF)group exhibited notably increased CD31+endothelial cells and activation of VEGFR2/ERK signaling pathway in the regenerated nerve tissues,which probably contributed to the improved nerve regeneration.Altogether,the comprehensive strategy including VEGF overexpressing Schwann cells-mediated and HSPS conduit-guided peripheral nerve repair provides a new avenue for nerve tissue engineering.