慢性牙周炎中淀粉样前体蛋白家族的表达研究
Study on the expression of amyloid precursor protein family in chronic periodontitis

目的·观察淀粉样前体蛋白（APP）家族在慢性牙周炎牙龈组织中的表达情况，及其在炎症微环境下人牙龈成纤维细胞（HGF）中的表达。方法·采用real-time PCR技术和免疫组化法分别检测健康成人和慢性牙周炎病例牙龈组织中APP家族基因和蛋白表达变化。体外培养HGF细胞，用1 μg/mL牙龈卟啉单胞菌脂多糖（P. g-LPS）模拟炎症微环境，运用real-time PCR技术检测APP家族基因表达。结果·慢性牙周炎组与健康组相比，APP和APLP2基因和蛋白表达均显著升高，APLP1无明显变化。HGF细胞在P. g-LPS刺激后APP、APLP1和APLP2基因表达均升高。结论·APP家族可能在慢性牙周炎发生发展过程中发挥一定作用。
： Objective·To observe the expression of amyloid precursor protein (APP) family in chronic periodontitis-affected gingival tissues and in human gingival fibroblasts (HGFs) under inflammatory microenvironment. Methods·Gene expression and protein level of APP family in healthy and chronic periodontitis-affected gingival tissues were measured by real-time PCR and immunohistochemistry (IHC) respectively. HGFs were cultured in vitro. The inflammatory microenvironment was simulated by 1 μg/mL lipopolysaccharide from P. gingivalis (P. g-LPS). The gene expression of APP family in HGFs was also measured using real-time PCR. Results·The gene expression and protein level of APP and APLP2 significantly increased in chronic periodontitis-affected gingival tissues compared with healthy gingival tissues, while the gene expression of APLP1 showed no significant change. The gene expressions of APP, APLP1, and APLP2 in HGFs all increased after being treated with P. g-LPS. Conclusion·APP family may play a role in the occurrence and development of chronic periodontitis