Renhao Sun1,2, Chunxi Zhang1, Yicong Liu3, Zhenggang Chen1, Wen Liu2, Fang Yang1, Fei Zeng1, Qingyuan Guo4,5. 1. Department of Stomatology, Qingdao Municipal Hospital, Qingdao, China. 2. School of Stomatology, Dalian Medical University, Dalian, China. 3. School of Stomatology, Qingdao University, Qingdao, China. 4. Department of Stomatology, Qingdao Municipal Hospital, Qingdao, China. guoqingyuanqd@163.com. 5. School of Stomatology, Qingdao University, Qingdao, China. guoqingyuanqd@163.com.
Abstract
BACKGROUND: In orthodontics, mechanical stress plays an important role in the process of bone remodeling. Mechanical stress has an effect on osteogenic differentiation of bone marrow-derived mesenchymal stem cells (BMSCs). However, the mechanism remains to be studied. The aim of this study is to investigate the effects of demethyltransferase fat mass and obesity-associated (FTO) on osteogenic differentiation of BMSCs under mechanical stress condition. METHODS AND RESULTS: The rat BMSCs were cultured in vitro, followed by flow cytometry to identify the cell surface antigens. Osteogenic differentiation of BMSCs was induced by mechanical stress by using the flexcell tension system for 6 h every day and 3 days in total. BMSCs were transfected by using plasmid for FTO knockdown. The expression level of FTO, hypoxia-inducible factor (HIF)-1α, runt-related transcription factor 2 (RUNX2), bone morphogenetic proteins (BMPs) and alkaline phosphatase (ALP) were measured by real-time qPCR, western blotting. ALP activity were determined by ALP staining assays. The expression of FTO and HIF-1α in BMSCs with mechanical stress were significantly higher than BMSCs without mechanical stress, also, the expression of osteogenic differentiation markers were higher in BMSCs with mechanical stress. Knockdown of FTO decreased expression of osteogenic differentiation marker and ALP activity in stretched BMSCs. In addition, the expression of HIF-1α was decreased after knocking down FTO. CONCLUSIONS: FTO promotes the expression of HIF-1α and osteogenic differentiation under the condition of mechanical stress. This finding may facilitate the clinical application of orthodontics and the mechanism research of mechanical stress-induced osteogenesis.
BACKGROUND: In orthodontics, mechanical stress plays an important role in the process of bone remodeling. Mechanical stress has an effect on osteogenic differentiation of bone marrow-derived mesenchymal stem cells (BMSCs). However, the mechanism remains to be studied. The aim of this study is to investigate the effects of demethyltransferase fat mass and obesity-associated (FTO) on osteogenic differentiation of BMSCs under mechanical stress condition. METHODS AND RESULTS: The rat BMSCs were cultured in vitro, followed by flow cytometry to identify the cell surface antigens. Osteogenic differentiation of BMSCs was induced by mechanical stress by using the flexcell tension system for 6 h every day and 3 days in total. BMSCs were transfected by using plasmid for FTO knockdown. The expression level of FTO, hypoxia-inducible factor (HIF)-1α, runt-related transcription factor 2 (RUNX2), bone morphogenetic proteins (BMPs) and alkaline phosphatase (ALP) were measured by real-time qPCR, western blotting. ALP activity were determined by ALP staining assays. The expression of FTO and HIF-1α in BMSCs with mechanical stress were significantly higher than BMSCs without mechanical stress, also, the expression of osteogenic differentiation markers were higher in BMSCs with mechanical stress. Knockdown of FTO decreased expression of osteogenic differentiation marker and ALP activity in stretched BMSCs. In addition, the expression of HIF-1α was decreased after knocking down FTO. CONCLUSIONS: FTO promotes the expression of HIF-1α and osteogenic differentiation under the condition of mechanical stress. This finding may facilitate the clinical application of orthodontics and the mechanism research of mechanical stress-induced osteogenesis.
Authors: Raghu R Edupuganti; Simon Geiger; Rik G H Lindeboom; Hailing Shi; Phillip J Hsu; Zhike Lu; Shuang-Yin Wang; Marijke P A Baltissen; Pascal W T C Jansen; Martin Rossa; Markus Müller; Hendrik G Stunnenberg; Chuan He; Thomas Carell; Michiel Vermeulen Journal: Nat Struct Mol Biol Date: 2017-09-04 Impact factor: 15.369
Authors: Magdalena A Machnicka; Kaja Milanowska; Okan Osman Oglou; Elzbieta Purta; Malgorzata Kurkowska; Anna Olchowik; Witold Januszewski; Sebastian Kalinowski; Stanislaw Dunin-Horkawicz; Kristian M Rother; Mark Helm; Janusz M Bujnicki; Henri Grosjean Journal: Nucleic Acids Res Date: 2012-10-30 Impact factor: 16.971