Decreased osteogenesis of adult mesenchymal stem cells by reactive oxygen species under cyclic stretch: a possible mechanism of age related osteoporosis.
Age related defect of the osteogenic differentiation of mesenchymal stem cells (MSCs) plays a key role in osteoporosis. Mechanical loading is one of the most important physical stimuli for osteoblast differentiation. Here, we compared the osteogenic potential of MSCs from young and adult rats under three rounds of 2 h of cyclic stretch of 2.5% elongation at 1 Hz on 3 consecutive days. Cyclic stretch induced a significant osteogenic differentiation of MSCs from young rats, while a compromised osteogenesis in MSCs from the adult rats. Accordingly, there were much more reactive oxygen species (ROS) production in adult MSCs under cyclic stretch compared to young MSCs. Moreover, ROS scavenger N-acetylcysteine rescued the osteogenic differentiation of adult MSCs under cyclic stretch. Gene expression analysis revealed that superoxide dismutase 1 (SOD1) was significantly downregulated in those MSCs from adult rats. In summary, our data suggest that reduced SOD1 may result in excessive ROS production in adult MSCs under cyclic stretch, and thus manipulation of the MSCs from the adult donors with antioxidant would improve their osteogenic ability.
Department of Orthodontics, Guanghua School of Stomatology, Hospital of Stomatology, Sun Yat-sen University, & Guangdong Provincial Key Laboratory of Stomatology , Guangzhou, China.
Jiali
J
Tan
State Key Laboratory of Oral Diseases, West China Hospital of Stomatology, Sichuan University , Chengdu, China.
Xin
X
Xu
Department of Orthodontics, Guanghua School of Stomatology, Hospital of Stomatology, Sun Yat-sen University, & Guangdong Provincial Key Laboratory of Stomatology , Guangzhou, China.
Zhongchun
Z
Tong
Department of Orthodontics, Guanghua School of Stomatology, Hospital of Stomatology, Sun Yat-sen University, & Guangdong Provincial Key Laboratory of Stomatology , Guangzhou, China.
Jiong
J
Lin
Department of Medicine, Division of Cardiovascular Medicine Brigham and Women's Hospital, Harvard Medical School, New Research Building, Room 630N , 77 Avenue Louis Pasteur, Boston, MA, USA.
Qiujun
Q
Yu
Department of Orthodontics, Guanghua School of Stomatology, Hospital of Stomatology, Sun Yat-sen University, & Guangdong Provincial Key Laboratory of Stomatology , Guangzhou, China.
Yao
Y
Lin
Department of Stomatology, Guangzhou General Hospital of Guangzhou Military Command , 111 Liuhua Road, Guangzhou, China.
Wei
W
Kuang