Effects of insulin-like growth factor I on the development of osteoblasts in hyperglycemia.
The delayed wound healing of tooth extraction, the activation of alveolar absorption and the being hindered bone formation around the implants in diabetes are difficult to be solved for dentists. So, the aim of the study was to investigate the influences of hyperglycemia and insulin-like growth factor I (IGF-I) on osteoblasts. Osteoblasts were cultured in different conditions: normal glucose, mimic hyperglycemia, hyperglycemia with IGF-I, hyperglycemia with insulin. The proliferation and mineralization of osteoblasts were observed. As abnormal transport of glucose involved in the development of chronic complications in diabetes. The expression of glucose transporter 1 (GLUT1) was further evaluated by RT-PCR, immunofluorescence and Western blot in different groups. These results showed that hyperglycemia increased the proliferation and inhibited the mineralization of osteoblasts, while IGF-I seemed to reverse these effects. The levels of GLUT1 mRNA and protein in hyperglycemia were elevated by 51% and 35%, respectively, compared with that in normal glucose, while the levels in hyperglycemia with IGF-I were almost the same as that in normal glucose. In conclusion, the increased expression of GLUT1 may contribute to the delayed mineralization of osteoblasts in hyperglycemia. Also IGF-I may be a new drug for diabetic bone disease through normalizing the expression of GLUT1.
Fang
Ying
Y
Department of Prosthodontics, College of Stomatology, Fourth Military Medical University, ChangLeXi Road, XinCheng District, Xi'an 710032, Shan-Xi province, China. fangying@fmmu.edu.cn
Wang
Zhong-Yi
ZY
Mao
Yong
Y
Xin
Hai-Tao
HT
Ren
Guang-Li
GL
Bai
Xue-Fan
XF
D000818:Animals; D002118:Calcium / Q000378:metabolism; D002478:Cells, Cultured; D051272:Glucose Transporter Type 1 / Q000096:biosynthesis; D006943:Hyperglycemia / Q000473:pathology*; D007328:Insulin / Q000494:pharmacology; D007334:Insulin-Like Growth Factor I / Q000494:pharmacology*; D010006:Osteoblasts / Q000166:cytology* / Q000187:drug effects; D051381:Rats
D051272:Glucose Transporter Type 1; D007328:Insulin; C495679:Slc2a1 protein, rat; D007334:Insulin-Like Growth Factor I; D002118:Calcium