Armstrong Stephanie J, Wiberg Mikael, Terenghi Giorgio, Kingham Paul J
Blond McIndoe Laboratories, The University of Manchester, Manchester, UK.
Neurosci Lett. 2008 Jul 4;439(1):42-6. doi: 10.1016/j.neulet.2008.04.091. Epub 2008 May 1.
Extracellular matrix (ECM) molecules and Schwann cells (SCs) are important components of peripheral nerve regeneration. In this study, the role of the transcription factor nuclear factor kappa B (NF-kappaB) in SC activation in response to laminin and the subsequent effect on in vitro neurite outgrowth was investigated. Immunocytochemistry and Western blot analysis showed that compared with poly-d-lysine (PDL), laminin enhanced the phosphorylation of IkappaB and p65 NF-kappaB signalling proteins in SCs. Phospho NF-kappaB-p65 was localised to the nucleus indicating activation of NF-kappaB. To assess the functional effect of NF-kappaB activation, SCs plated on PDL or laminin were pre-treated with NF-kappaB inhibitors, 6-amino-4-(4-phenoxyphenylethylamino)quinazoline (QNZ) or Z-leu-leu-leu-CHO (MG-132) before NG108-15 neuronal cells were seeded on the SC monolayer. After 24h co-culture in the absence of inhibitors, SCs seeded on laminin enhanced the mean number and length of neurites extended by NG108-15 cells (1.87+/-0.13 neurites; 238.74+/-8.53microm) compared with those cultured in the presence of SCs and PDL (1.26+/-0.07 neurites; 157.57+/-9.80microm). At 72h, neurite length had further increased to 321.83+/-6.60microm in the presence of SCs and laminin. Inhibition of NF-kappaB completely abolished the effect of laminin on SC evoked neurite outgrowth at 24h and reduced the enhancement of neurite length by over 60% at 72h. SC proliferation was unaffected by NF-kappaB inhibition suggesting that the NF-kappaB signalling pathway plays a discrete role in the activation of SCs and their neurotrophic potential.
细胞外基质（ECM）分子和雪旺细胞（SCs）是周围神经再生的重要组成部分。在本研究中，研究了转录因子核因子κB（NF-κB）在雪旺细胞对层粘连蛋白反应的激活中的作用以及随后对体外神经突生长的影响。免疫细胞化学和蛋白质印迹分析表明，与聚-D-赖氨酸（PDL）相比，层粘连蛋白增强了雪旺细胞中IkappaB和p65 NF-κB信号蛋白的磷酸化。磷酸化的NF-κB-p65定位于细胞核，表明NF-κB被激活。为了评估NF-κB激活的功能作用，在将NG108-15神经元细胞接种到雪旺细胞单层之前，用NF-κB抑制剂6-氨基-4-（4-苯氧基苯乙氨基）喹唑啉（QNZ）或Z-亮氨酸-亮氨酸-亮氨酸-CHO（MG-132）对接种在PDL或层粘连蛋白上的雪旺细胞进行预处理。在不存在抑制剂的情况下共培养24小时后，与在雪旺细胞和PDL存在下培养的细胞相比，接种在层粘连蛋白上的雪旺细胞增强了NG108-15细胞伸出的神经突的平均数量和长度（1.87±0.13个神经突；238.74±8.53微米）（1.26±0.07个神经突；157.57±9.80微米）。在72小时时，在雪旺细胞和层粘连蛋白存在下神经突长度进一步增加到321.83±6.60微米。NF-κB的抑制在24小时时完全消除了层粘连蛋白对雪旺细胞诱发的神经突生长的影响，并在72小时时将神经突长度的增加降低了60%以上。雪旺细胞增殖不受NF-κB抑制的影响，这表明NF-κB信号通路在雪旺细胞的激活及其神经营养潜能中起离散作用。
