Experimental study of O-GlcNAc on the influence of the upper lip development through inhibition of Wnt signa-ling pathway

Abstract

Objective To explore the role of Wnt signaling pathway in the process of epithelial layer's disappearance when Oxydiethanoldiethylene GlcNAc influence development of upper lip. Methods The over/lower-expression of O-GlcNAc and reverse-high expression experimental group was constructed by transplanting beads into the upper lip of chicken embryo which contain O-GlcNAc promoter OGT (O-GlcNAc transferase), O-GlcNAc inhibitor OGA (O-GlcNAcase) or OGA inhibitor STZ(streptozoticin). and kept incubation for 24 h. Phenotypic analysis of skeletal and morphological changes were performed by using Alizarin Red/Alcian Blue method. TUNEL assay was performed to analyze the cell apoptosis. Immunohistochemistry method was performed to test the Wnt signaling pathway including GSK-3β, β-catenin. Results In the group OGZ and STZ where O-GlcNAc was overexpressed, disappearance of the epithelial layers was delayed, embryo lips appeared bone defect in bonestaining, compared with the normal group, obvious cell apoptosis has not been found in TUNEL detection.But expression of GSK-3 beta increased in the cytoplasm, expression of beta-catenin nucleus reduced, upper lip development of normal side and the low expression of O-GlcNAc in the OGA group were not affected. Conclusion Overexpression of O-GlcNAc may lead to a delay of epithelial disappearance which was not caused by the apoptosis but maybe caused by inhibiting Wnt signaling pathway. The process can change related signaling factors including GSK-3 beta, beta-catenin, which may influence the development of upper lip and in the end lead to cleft lip and palate.

Keywords

• Wnt signaling pathway，
• O-linked N-acetylglucosamine，
• Cell apoptosis，
• Chicken embryo，
• Upper lip，