Nakazawa-Tanaka Nana, Fujiwara N, Miyahara K, Nakada S, Arikawa-Hirasawa E, Akazawa C, Urao M, Yamataka A
Department of Pediatric Surgery, Juntendo University Nerima Hospital, 3-1-10 Takanodai Nerima-ku, Tokyo, 177-8521, Japan.
Department of Pediatric Surgery, Juntendo University School of Medicine, Tokyo, Japan.
Pediatr Surg Int. 2018 Feb;34(2):143-147. doi: 10.1007/s00383-017-4181-5. Epub 2017 Oct 10.
BACKGROUND/AIM: Laminin-1 regulates neurite outgrowth in various neuronal cells. We have previously demonstrated that laminin-1 promotes enteric neural crest-derived cell (ENCC) migration by using Sox10-VENUS transgenic mice, in which ENCCs are labeled with a green fluorescent protein, Venus. Mice lacking the endothelin-B receptor gene, Ednrb mice, are widely used as a model for Hirschsprung's disease (HD). The aim of this study was to investigate the effects of laminin-1on ENCC migration in Sox10-VENUS/Ednrb mice, a newly created HD mice model.
Fetal guts were dissected on embryonic day 12.5 (E12.5). Specimens were incubated either with, or without laminin-1 for 24 h and images were taken under a stereoscopic microscope. The length from the stomach to the wavefront of ENCC migration (L-E) and the total length of the gut (L-G) were measured. Changes in the ratio of L-E to L-G (L-E/L-G) after 24 h were calculated.
On E12.5, the wavefront of ENCC migration in the HD gut samples was located in the midgut, whereas the wavefront of ENCC in Sox10-VENUS/Ednrb (WT) samples had reached the hindgut. After 24 h, L-E/L-G had increased by 1.49%, from 34.97 to 36.46%, in HD gut and had increased by 1.07%, from 48.08 to 49.15%, in HD with laminin-1, suggesting there was no positive effect of laminin-1 administration on ENCC migration in HD.
Our results suggest that laminin-1 does not have a positive effect on ENCC migration in HD mice on E12.5, in contrast to the phenomenon seen in normal mice gut specimens, where laminin-1 promotes ENCC migration during the same period. This suggests that there is an impairment in the interaction between ENCC and extracellular environmental factors, which are required for normal development of the enteric nervous system, resulting in an aganglionic colon in HD.
背景/目的：层粘连蛋白-1调节多种神经元细胞的神经突生长。我们之前利用Sox10-VENUS转基因小鼠证明了层粘连蛋白-1可促进肠神经嵴衍生细胞（ENCC）迁移，在该转基因小鼠中，ENCCs被绿色荧光蛋白Venus标记。缺乏内皮素B受体基因的小鼠（Ednrb小鼠）被广泛用作先天性巨结肠（HD）的模型。本研究的目的是探讨层粘连蛋白-1对新创建的HD小鼠模型Sox10-VENUS/Ednrb小鼠中ENCC迁移的影响。
在胚胎第12.5天（E12.5）解剖胎儿肠道。将标本分别在有或无层粘连蛋白-1的情况下孵育24小时，并在立体显微镜下拍照。测量从胃到ENCC迁移波前的长度（L-E）和肠道的总长度（L-G）。计算24小时后L-E与L-G的比值（L-E/L-G）的变化。
在E12.5时，HD肠道样本中ENCC迁移的波前位于中肠，而Sox10-VENUS/Ednrb（野生型）样本中ENCC的波前已到达后肠。24小时后，HD肠道中L-E/L-G从34.97%增加到36.46%，增加了1.49%，在添加层粘连蛋白-1的HD中从48.08%增加到49.15%，增加了1.07%，这表明给予层粘连蛋白-1对HD中ENCC迁移没有积极作用。
我们的结果表明，与正常小鼠肠道标本中观察到的层粘连蛋白-1在同一时期促进ENCC迁移的现象相反，层粘连蛋白-1对E12.5的HD小鼠中ENCC迁移没有积极作用。这表明在ENCC与细胞外环境因素之间的相互作用存在缺陷，而这是肠神经系统正常发育所必需的，从而导致HD中的无神经节结肠。
