低氧上调lncRNA-01126/HIF-1α/MAPK通路促进牙周炎发生发展的机制研究

Since periodontitis is one of the most prevalent oral diseases, the deep exploration of its pathogenic mechanism is significant for the early prevention. Previous studies indicate that improving hypoxia microenvironment may induce the periodontitis, while hypoxia inducible factor-1α (HIF-1α) is a major transcriptional factor. However, the mechanism of molecular regulatory pathways for HIF-1α is not well understood. In the preliminary study, we have found that an altered high-level expression of the tissue-specific long non-coding RNA (lncRNA-01126) in periodontitis tissue and human periodontal ligament cells (hPDLCs) cultured in hypoxia by chip inspections; meanwhile, the interference specific for lncRNA-01126 resulted in down-regulated expressions of HIF-1α and the related protein. Therefore, we proposed a hypothesis that hypoxia may up-regulate lncRNA-01126/HIF-1α/MAPK signaling pathway to promote periodontitis. Therefore, in the following study, we will use bioinformatics analysis, chip assay, RNA-pull down assay, RNA interference methods and ectopic osteogenesis in vivo to clarify the points as follows: (1) the biological functions of lncRNA-01126 in hPDLCs; (2) the specific binding sites of lncRNA-01126 and HIF-1α; (3) the regulatory mechanism of lncRNA-01126/HIF-1α/MAPK signaling pathway in the progression of periodontitis. We expect to provide new molecular targets and experimental evidences for the early diagnosis and treatment of periodontitis.

牙周炎是人类主要口腔疾患之一，深入探究其发病机制对疾病的早期防治具有重要意义。以往研究提示低氧对牙周炎有促进作用，但具体机制尚不清楚。项目组前期研究发现牙周炎组织和低氧培养的牙周膜细胞中lncRNA-01126高表达；沉默该lncRNA后HIF-1α表达下调，且MAPK通路相关基因表达也降低，因此，项目组提出低氧上调lncRNA-01126/HIF-1α/MAPK通路促进牙周炎发生发展的假说。本课题拟通过生物信息学、RNA干扰、RNA-IP和Pull down等技术及体内外实验，明确lncRNA-01126对牙周膜细胞生物学行为的影响，鉴定其与HIF-1α的特异性结合位点，探讨低氧微环境中lncRNA-01126/HIF-1α/MAPK通路对牙周炎的调控机制。这将另辟蹊径从lncRNA角度寻找牙周炎早期防治的新靶点，探索牙周炎修复性治疗的新策略，具有很好的临床转化前景。

牙周炎是人类主要口腔疾患之一，是成人牙齿丧失的主要原因。牙周炎与多种高发全身系统性疾病密切相关，严重影响了人类口腔及全身健康。牙周炎症可导致牙周膜细胞局部缺氧，然而，缺氧相关的长链非编码RNA参与牙周炎的机制在很大程度上仍不清楚。项目组通过临床标本高通量筛查和生物信息学分析，筛选了牙周炎差异表达量最高的lncRNA-01126，检测了lncRNA -01126对牙周膜细胞生物学行为的影响。体外实验表明，lncRNA-01126通过海绵吸附miR-518a-5p，抑制低氧hPDLCs的增殖，促进细胞凋亡和炎症反应。此外，我们发现HIF-1α是hPDCLs中miR-518a-5p的直接靶点，而lncRNA-01126通过调控miR-518a-5p/HIF-1α/MAPK通路促进牙周炎的发病机制。综上，lncRNA-01126通过miR-518a-5p/HIF-1α/MAPK通路促进hPDLCs的牙周炎发病机制，为lncRNA-01126用于牙周早期诊治提供了可能的思路。