Regulation of mandibular condylar chondrocyte differentiation by mechanosensitive microRNA

2019 Fiscal Year Final Research Report

• Project/Area Number: 17K11941
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Orthodontics/Pediatric dentistry
• Research Institution: Kyushu University
• Principal Investigator: Hoshi Kenji 九州大学, 大学病院, 助教 (90569964)
• Co-Investigator(Kenkyū-buntansha): 高橋 一郎 九州大学, 歯学研究院, 教授 (70241643) ; 野村 俊介 九州大学, 歯学研究院, 助教 (60710994)
• Project Period (FY): 2017-04-01 – 2020-03-31
• Keywords: 下顎頭軟骨 / メカニカルストレス / microRNA / 間葉系細胞

Outline of Final Research Achievements

According to the microarray analysis in our previous research, we have selected five candidate microRNAs (miRNAs) which might function as mechanosensitive miRNAs in murine condylar cartilage. We transfected the five miRNAs to mesenchymal stromal cells isolated from anlagen of murine mandibular condylar cartilages, and performed cell proliferation analysis. This analysis revealed that one of the five miRNAs significantly repressed the cell proliferation. Furthermore, we examined the time-course change of expressions of the five miRNAs from prenatal stage to postnatal growth stage. According to the analysis, we divided the five miRNAs into the following three groups; miRNAs that were strongly expressed in prenatal stage, miRNAs that kept higher expression throughout growth stage, and miRNAs that remarkably increased expression after reaching full growth. These result indicated that the five miRNAs might control the growth of mandibular condylar cartilage in stage specific manners.

Free Research Field

矯正歯科

Academic Significance and Societal Importance of the Research Achievements

下顎頭軟骨は、下顎骨の成長を制御する重要な解剖学的構造の一つである。これの成長の制御が幼少期の矯正歯科治療において試みられているが、効果のばらつきは依然大きく、人為的な制御と呼べる段階ではない。これは、下顎頭軟骨の矯正力（メカニカルストレス）に対する応答の詳細が解明できていないことも大きな原因の一つである。本研究より、マウス下顎頭軟骨のメカニカルストレス応答に関する重要な知見が得られた。本研究より得られた結果は、矯正力による下顎頭軟骨の成長発育の人為的制御に繋がり得る成果の一つであるといえる。