Response of bone marrow mesenchymal stem cells to mechanical stretch and gene expression of transforming growth factor-beta and insulin-like growth factor-II under mechanical strain.
- Author:
Li-chi HAN
1
;
Meng-chun QI
;
Hong SUN
;
Jing HU
;
Shu-juan ZOU
;
Ji-hua LI
Author Information
- Publication Type:Journal Article
- MeSH: Animals; Bone Marrow Cells; Cell Differentiation; Cell Proliferation; Insulin-Like Growth Factor II; Mesenchymal Stromal Cells; Osteogenesis; Osteogenesis, Distraction; RNA, Messenger; Rats; Rats, Sprague-Dawley; Somatomedins; Transforming Growth Factor beta
- From: West China Journal of Stomatology 2009;27(4):381-385
- CountryChina
- Language:Chinese
-
Abstract:
OBJECTIVETo study the response of rat bone marrow mesenchymal stem cells (MSCs) to a single period of mechanical strain and expression patterns of transforming growth factor-beta (TGF-beta) and insulin-like growth factor-II (IGF-II) after mechanical stretch.
METHODSBone marrow MSCs were isolated from SD rats and cultured in vitro. A four-point bending apparatus were used to perform a single period of mechanical strain (2000 microepsilon, 40 min) on MSCs. Cellular proliferation and alkaline phosphatase (ALP) activity of MSCs were examined and gene expression patterns of TGF-beta and IGF-II were detected by SYBR green quantitative real-time RT-PCR.
RESULTSCell proliferation, ALP activity and expression of TGF-beta and IGF-II were all significantly up-regulated in stretched MSCs when compared with their controls. The mRNA levels of TGF-beta and IGF-II got top increase immediately after mechanical loading and increased about 51.44 and 8.92 folds, respectively, when compared with control cells. Expression of TGF-beta and IGF-II decreased with time and returned to control level at 12 h after mechanical stimulus, despite of a small increase at 6 h.
CONCLUSIONThe mechanical stretch can promote MSCs proliferation, up-regulate its ALP activity and induce a time-dependent expression increase of TGF-beta and IGF-II which in turn result in osteogenic differentiation of MSCs. Mechanical stimulus is a key stimulator for osteogenic differentiation of MSCs and vital for bone formation in distraction osteogenesis.