Li Ma, Bing Shi, Qian Zheng
Dept. of Stomatology, Shandong Provincial Hospital Affiliated to Shandong University, Jinan 250021, China;State Key Laboratory of Oral Diseases & National Clinical Research Center for Oral Diseases & Dept. of Cleft Lip and Palate Surgery, West China Hospital of Stomatology, Sichuan University, Chengdu 610041, China.
State Key Laboratory of Oral Diseases & National Clinical Research Center for Oral Diseases & Dept. of Cleft Lip and Palate Surgery, West China Hospital of Stomatology, Sichuan University, Chengdu 610041, China.
Hua Xi Kou Qiang Yi Xue Za Zhi. 2018 Feb 1;36(1):9-16. doi: 10.7518/hxkq.2018.01.003.
This study aims to investigate whether dexamethasone (DEX) can down-regulate the PAR complex and disrupt the cell polarity in the palatal epithelium during palatal fusion.
Pregnant rats were randomly divided into control and DEX groups, which were injected intraperitoneally with 0.9% sodium chloride (0.1 mL) and DEX (6 mg·kg ⁻¹), respectively, every day from E10 to E12. The palatal epithelial morphology was observed using hematoxylin and eosin staining and scanning electron microscopy. Immunofluorescence staining, Western Blot analysis, and real-time polymerase chain reaction were performed to detect the expression of PAR3, PAR6, and aPKC.
The incidence of cleft palate in DEX group (46.15%) was significantly higher than that in control group (3.92%), and the difference was statistically significant (χ2=24.335, P=0.00). DEX can also retard the growth of the palatal shelves and the short palatal shelves. The morphology and arrangement of MEE cells changed from polarized bilayer cells to nonpolarized monolayer ones. Additionally, the spherical structure decreased, which caused the cleft palate. PAR3 and PAR6 were only detected in the palatal epithelium, and aPKC was expressed in the palatal epithelium and mesenchyme. DEX can reduce the expression levels of PAR3, PAR6, and aPKC in the protein and gene levels.
DEX can down-regulate the complex gene expression in the MEE cells, thereby destroying the cell polarity and causing cleft palate.
本研究旨在探讨地塞米松（DEX）是否能下调腭融合过程中腭上皮中的PAR复合物并破坏细胞极性。
将孕鼠随机分为对照组和DEX组，从胚胎第10天（E10）至第12天（E12）每天分别腹腔注射0.9%氯化钠（0.1 mL）和DEX（6 mg·kg⁻¹）。采用苏木精-伊红染色和扫描电子显微镜观察腭上皮形态。进行免疫荧光染色、蛋白质印迹分析和实时聚合酶链反应以检测PAR3、PAR6和非典型蛋白激酶C（aPKC）的表达。
DEX组腭裂发生率（46.15%）显著高于对照组（3.92%），差异具有统计学意义（χ2=24.335，P=0.00）。DEX还可延缓腭突生长及使腭突短小。正中腭上皮（MEE）细胞的形态和排列从极化的双层细胞变为非极化的单层细胞。此外，球形结构减少，导致腭裂。PAR3和PAR6仅在腭上皮中检测到，aPKC在腭上皮和间充质中表达。DEX可在蛋白质和基因水平降低PAR3、PAR6和aPKC的表达水平。
DEX可下调MEE细胞中的复合物基因表达，从而破坏细胞极性并导致腭裂。
