title: [The effect of mechanical strain on proliferation and osteogenic differentiation of bone marrow mesenchymal stem cells from rats].
abstract: In order to investigate the effects of cyclic biaxial mechanical strain on proliferation and osteogenic differentiation of bone marrow mesenchymal stem cells (MSCs)from rats. The MSCs were isolated from bone marrow in the 9-month-old female Sprague-Dawley rats by a density gradient method. After the third passage,1 x 10(5) cells were seeded on the flexible silicone membrane in the cyclic biaxial mechanical strain unit. The amplitude of mechanical strain applied to the cells were 4000 microstrain, at a frequency of one hertz (1 Hz), for periods of 3 repetitions of 2 hours' mechanical strain and a break of 2 hours. The osteoblastic marker such as osteopontin (OPN),alkaline phosphatease (ALP), osteocalcin (OCN), type I collagen (Col I) were detected by RT-PCR. The proliferation of all cells were studied with Flow Cytometry (FCM). ALP and OPN levels significantly increased in the mechanical strained groups and reached the top at 3th day after mechanical strain. COL I level was increase only at 3th day after mechanical strain, and the change of OCN was not obvious in every group. The proliferation index of the medchanical strained groups was increased, compared with the control. These results showed that mechanical strain can improve MSCs proliferation and make MSCs differentiate to osteoblast.
authors.affiliation: Institute of Biomedical Engineering, Basic Medicine and Forensic Medicine College, Sichuan University, Chengdu 610041, China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Jing
authors.forename: Liang
authors.initials: L
authors.lastname: Li
authors.forename: Yi
authors.initials: Y
authors.lastname: Li
authors.forename: Mengshi
authors.initials: M
authors.lastname: Chen
authors.forename: Wenchao
authors.initials: W
authors.lastname: Wu
authors.forename: Huaiqing
authors.initials: H
authors.lastname: Chen
authors.forename: Xiaojing
authors.initials: X
authors.lastname: Liu
mesh_terms: D000469:Alkaline Phosphatase / Q000032:analysis; D000818:Animals; D001696:Biomechanical Phenomena; D001854:Bone Marrow Cells / Q000166:cytology; D002454:Cell Differentiation; D049109:Cell Proliferation; D002478:Cells, Cultured; D005260:Female; D059630:Mesenchymal Stem Cells / Q000166:cytology*; D010006:Osteoblasts / Q000166:cytology*; D015675:Osteocalcin / Q000032:analysis; D053495:Osteopontin / Q000032:analysis; D051381:Rats; D017207:Rats, Sprague-Dawley
chemical_list: D015675:Osteocalcin; D053495:Osteopontin; D000469:Alkaline Phosphatase