Department of Oral & Maxillofacial Surgery, State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases & Other Research Platforms, West China Hospital of Stomatology, Sichuan University, Chengdu, China.
Division of Oral Biology, Tufts University School of Dental Medicine, Boston, MA, USA.
J Periodontal Res. 2020 Apr;55(2):191-198. doi: 10.1111/jre.12701. Epub 2019 Sep 21.
Periodontitis is a prevalent oral disease responsible for tooth loss. MicroRNAs have been proven crucial in bone disorders over the past decades. Promotive effect on osteogenic activities by microRNA-335-5p (miR-335-5p) has been well demonstrated, but its role involved in the pathogenesis of periodontitis remains elusive. In this study, we established experimental periodontitis (EP) on transgenic mice overexpressing miR-335-5p (335-Tg) to investigate the novel effects of miR-335-5p on periodontal inflammation and bone loss.
Experimental periodontitis was established via ligation. The expression of inflammatory and osteoclastic genes was examined by quantitative real-time PCR (qPCR). Morphology of alveolar bone was analyzed by microcomputed tomography (μCT). Hematoxylin and eosin (H&E), tartrate-resistant acid phosphatase (TRAP), and Toll-like receptor 4 (TLR4) immunohistochemistry (IHC) staining were conducted for histological analysis.
The expression of miR-335-5p decreased significantly in the periodontal tissues of EP. Compared to the WT-EP group, μCT analysis showed less bone loss in the 335-Tg-EP group accompanying with a decreased number of TRAP-positive osteoclasts. H&E and IHC staining exhibited attenuated inflammation and TLR4 expression in the 335-Tg-EP group. Furthermore, reduced expressions of IL-1β, IL-6, TNF-α, and TLR4 were also detected in the 335-Tg-EP group. Overexpression of miR-335-5p in vivo weakened the periodontal bone destruction and inflammation compared with the WT-EP group.
Our data exhibit novel roles of miR-335-5p in preventing bone loss and inflammation in experimental periodontitis.
牙周炎是一种常见的口腔疾病，可导致牙齿脱落。过去几十年来，microRNAs 已被证明在骨骼疾病中起着至关重要的作用。microRNA-335-5p（miR-335-5p）对成骨活性有促进作用，但它在牙周炎发病机制中的作用仍不清楚。在本研究中，我们在过表达 miR-335-5p 的转基因小鼠上建立了实验性牙周炎（EP）模型，以研究 miR-335-5p 对牙周炎症和骨丢失的新作用。
通过结扎建立实验性牙周炎。通过定量实时 PCR（qPCR）检测炎症和破骨细胞基因的表达。通过微计算机断层扫描（μCT）分析牙槽骨形态。进行苏木精和伊红（H&E）、抗酒石酸酸性磷酸酶（TRAP）和 Toll 样受体 4（TLR4）免疫组织化学（IHC）染色进行组织学分析。
miR-335-5p 在牙周组织中的表达在 EP 中显著降低。与 WT-EP 组相比，335-Tg-EP 组的 μCT 分析显示骨丢失较少，TRAP 阳性破骨细胞数量减少。H&E 和 IHC 染色显示 335-Tg-EP 组炎症和 TLR4 表达减弱。此外，在 335-Tg-EP 组还检测到 IL-1β、IL-6、TNF-α和 TLR4 的表达减少。与 WT-EP 组相比，体内过表达 miR-335-5p 可减轻牙周骨破坏和炎症。
我们的数据显示 miR-335-5p 在预防实验性牙周炎中的骨丢失和炎症方面具有新的作用。
