Effects of GLUT1 and GLUT2 Mediated Glucose Uptake on Early Tooth Development in Mice
Objective:To explore the effects of glucose transporter(GLUT)1 and GLUT2 mediated glucose uptake on early tooth development in mice.Methods:The mandibular molar tooth germ and maxillary incisor tooth germ during embryonic day 13.5(E13.5),E14.5,E16.5,E18.5,and postnatal day 1(P1)were collected.RT-qPCR and Western blot were used to detect Glut1 and Glut2 mRNA and protein levels in tooth germ.Immuno-histochemical staining was used to detect GLUT1,GLUT2,Ki67,and glycogen levels in tooth germ.The mandib-ular molar tooth germ was cultivated in glucose-free DMEM medium and high glucose DMEM medium with differ-ent concentrations of Phloretin(0 mmol/L,0.25 mmol/L,0.5 mmol/L)for 9 days.Results:(1)During E13.5,GLUT1 was strongly expressed in enamel organ,with active cell proliferation and abundant deposition of glycogen in dental lamina and odontotheca.During E14.5 and E18.5,the expression of GLUT1 was gradually decreased in enamel organ,cell proliferation was decreased,and glycogen was heavily deposited in enamel organ and dental papil-lae.During P1,GLUT1 was highly expressed in middle layer and inner enamel epithelium,with increased cell pro-liferation and minimal deposition of glycogen in dental papilla.During the entire stage of tooth germ development,GLUT2 expression was relatively low.(2)GLUT1 was strongly expressed in preameloblasts and preodontoblasts cells,but less expressed in differentiated ameloblasts and odontoblasts cells.GLUT2 and GLUT1 exhibited opposite expression trends.(3)0.5 mmol/L Phloretin could inhibit the development of tooth germ in E13.5 stage,while 0.25 mmol/L root bark extract didn't inhibit the develop-ment of tooth germ in E13.5 and E14.5 stage,but could cause tooth germ to shrink and had a concentration depend-ent effect on Phloretin.Glucose-free culture medium could inhibit the development of explant dental germ in E13.5 and E14.5 stages.Conclusion:The expression of GLUT1 and GLUT2 in early tooth development were precisely spatiotemporal regulated,and GLUT1 and GLUT2 mediated glucose uptake played an important role in early tooth development in mice.
glucose transporter 1glucose transporter 2glucose uptakeearly development of teethphloretin