Mi Jie, Chen Dong, Ren Xiantan, Jia Huimin, Gao Hong, Wang Weilin
Department of Pediatric Surgery, Shengjing Hospital of China Medical University Liaoning, China.
Key Laboratory of Congenital Malformations, Ministry of Public Health, Shengjing Hospital of China Medical University Shenyang, Liaoning, China.
Int J Clin Exp Pathol. 2014 Apr 15;7(5):1997-2005. eCollection 2014.
Fecal incontinence and constipation after procedures for anorectal malformations (ARMs) are closely related to the maldevelopment of the striated muscle complex (SMC). Previous studies have demonstrated that myogenic regulatory factors (MRFs) play a significant role in muscle development. Wnt signal pathway is extremely important for MRFs regulation. This study was designed to investigate the spatiotemporal expression pattern of Wnt5a in SMC in ARMs rat embryos.
Anorectal malformation embryos were induced by ethylene thiourea on embryonic day 10 (E10). Expression levels of protein and mRNA of Wnt5a were confirmed by immunohistochemistry staining, western blot and quantitative real-time PCR (qRT-PCR) between normal rat embryos and embryos with ARMs.
Immunostaining revealed that, on embryonic day 17 (E17), the Wnt5a protein was initially expressed in the SMC in normal embryos. With the growth of pregnancy, the positive staining cells gradually increased. The same time-dependent changes of Wnt5a protein were detected in ARMs embryos. Besides, immunostaining showed that Wnt5a had a significant increase in normal embryos compared with ARMs embryos. Similarly, in Western blot and qRT-PCR, the higher expression of Wnt5a protein and mRNA were remarkable in normal embryos during the SMC development, relatively.
Our study demonstrated that the downregulation of Wnt5a at the time of SMC development might partly be related to the dysplasia of SMC in ARMs.
肛门直肠畸形(ARM)手术后的大便失禁和便秘与横纹肌复合体(SMC)发育异常密切相关。先前的研究表明,肌源性调节因子(MRF)在肌肉发育中起重要作用。Wnt信号通路对MRF的调节极为重要。本研究旨在探讨Wnt5a在ARM大鼠胚胎SMC中的时空表达模式。
在胚胎第10天(E10)用乙烯硫脲诱导肛门直肠畸形胚胎。通过免疫组织化学染色、蛋白质印迹法和定量实时PCR(qRT-PCR)确定正常大鼠胚胎和患有ARM的胚胎中Wnt5a的蛋白质和mRNA表达水平。
免疫染色显示,在胚胎第17天(E17),Wnt5a蛋白最初在正常胚胎的SMC中表达。随着孕期的增长,阳性染色细胞逐渐增加。在患有ARM的胚胎中也检测到Wnt5a蛋白的相同时间依赖性变化。此外,免疫染色显示正常胚胎中的Wnt5a与患有ARM的胚胎相比有显著增加。同样,在蛋白质印迹法和qRT-PCR中,在SMC发育过程中,正常胚胎中Wnt5a蛋白和mRNA的表达相对较高。
我们的研究表明,SMC发育时Wnt5a的下调可能部分与ARM中SMC发育异常有关。