摘要
AIM: To study the therapeutic effect of three tubeguides with electrical conductivity associated to mesenchymal stem cells(MSCs) on neuro-muscular regeneration after neurotmesis.METHODS: Rats with 10-mm gap nerve injury were tested using polyvinyl alcohol(PVA), PVA-carbon nanotubes(CNTs) and MSCs, and PVA-polypyrrole(PPy). The regenerated nerves and tibialis anterior muscles were processed for stereological studies after 20 wk. The functional recovery was assessed serially for gait biomechanical analysis, by extensor postural thrust, sciatic functional index and static sciatic functionalindex(SSI), and by withdrawal reflex latency(WRL). In vitro studies included cytocompatibility, flow cytometry, reverse transcriptase polymerase chain reaction and karyotype analysis of the MSCs. Histopathology of lung, liver, kidneys, and regional lymph nodes ensured the biomaterials biocompatibility. RESULTS: SSI remained negative throughout and independently from treatment. Differences between treted groups in the severity of changes in WRL existed, showing a faster regeneration for PVA-CNTs-MSCs(P < 0.05). At toe-off, less acute ankle joint angles were seen for PVA-CNTs-MSCs group(P = 0.051) suggesting improved ankle muscles function during the push off phase of the gait cycle. In PVA-PPy and PVA-CNTs groups, there was a 25% and 42% increase of average fiber area and a 13% and 21% increase of the "minimal Feret's diameter" respectively. Stereological analysis disclosed a significantly(P < 0.05) increased myelin thickness(M), ratio myelin thickness/axon diameter(M/d) and ratio axon diameter/fiber diameter(d/D; g-ratio) in PVA-CNT-MSCs group(P < 0.05). CONCLUSION: Results revealed that treatment with MSCs and PVA-CNTs tube-guides induced better nerve fiber regeneration. Functional and kinematics analysis revealed positive synergistic effects brought by MSCs and PVA-CNTs. The PVA-CNTs and PVA-PPy are promising scaffolds with electric conductive properties, bio- and cytocompatible that might prevent the secondary neurogenic muscular atrophy by improving the reestablishment of the neuro-muscular junction.
AIM To study the therapeutic effect of three tubeguideswith electrical conductivity associated tomesenchymal stem cells （MSCs） on neuro-muscularregeneration after neurotmesis.METHODS： Rats with 10-mm gap nerve injury weretested using polyvinyl alcohol （PVA）, PVA-carbonnanotubes （CNTs） and MSCs, and PVA-polypyrrole（PPy）. The regenerated nerves and tibialis anteriormuscles were processed for stereological studies after20 wk. The functional recovery was assessed serially forgait biomechanical analysis, by extensor postural thrust,sciatic functional index and static sciatic functional index （SSI）, and by withdrawal reflex latency （WRL）. Invitro studies included cytocompatibility, flow cytometry,reverse transcriptase polymerase chain reaction andkaryotype analysis of the MSCs. Histopathology of lung,liver, kidneys, and regional lymph nodes ensured thebiomaterials biocompatibility.RESULTS： SSI remained negative throughout andindependently from treatment. Differences betweentreted groups in the severity of changes in WRL existed,showing a faster regeneration for PVA-CNTs-MSCs （P〈 0.05）. At toe-off, less acute ankle joint angles wereseen for PVA-CNTs-MSCs group （P = 0.051） suggestingimproved ankle muscles function during the push offphase of the gait cycle. In PVA-PPy and PVA-CNTsgroups, there was a 25% and 42% increase of averagefiber area and a 13% and 21% increase of the ＂minimalFeret＇s diameter＂ respectively. Stereological analysisdisclosed a significantly （P 〈 0.05） increased myelinthickness （M）, ratio myelin thickness/axon diameter （M/d） and ratio axon diameter/fiber diameter （d/D; g-ratio）in PVA-CNT-MSCs group （P 〈 0.05）.CONCLUSION： Results revealed that treatmentwith MSCs and PVA-CNTs tube-guides induced betternerve fiber regeneration. Functional and kinematicsanalysis revealed positive synergistic effects brought byMSCs and PVA-CNTs. The PVA-CNTs and PVA-PPy arepromising scaffolds with electric conductive properties,bio- and cytocompatible that might prevent the secondaryneurogenic muscular atrophy by improving the reestablishmentof the neuro-muscular junction.
基金
Supported by System of Incentives for Research and Technological development of QREN in the scope of project n°38853/2013-DEXGELERATION:"Solucoes avancadas de regeneracao ossea com base em hidrogeis de dextrin"
the European Community FEDER fund through ON2-O Novo Norte-North Portugal Regional Operational Program 2007-2013
Project n°34128-BEPIM II:"Microdispositivos biomédicos com capacidade osteointegrativa porμPIM"
funded by Ad I
the program COMPETE-Programa Operacional Factores de Competitividade,projects Pest-OE/AGR/UI0211/2011
PTDC/CVT/103081/2008
CDRsp’s Strategic Project-UI-4044-2011-2012(Pest-OE/EME/UI4044/2011)funding from FCT
