XXXX mesenchymal stem cells are sensitive to abnormal gravity and exhibit classic apoptotic features.

@entity1 @entity522 @entity876 @entity12559
The aim of the present study was to investigate the effects of abnormal gravity on @entity1 mesenchymal stem cells (hMSCs). Strong magnetic field and magnetic field gradient generate a magnetic force that can add to or subtract from the gravitational force. In this study, this is defined as a high-magneto-gravitational environment (HMGE). The HMGE provides three apparent gravity levels, i.e. hypogravity ( g), hypergravity (2g) and normal gravity with strong magnetic field (1g) conditions. After hMSCs were subject to HMGE for 12 h, the proliferation, morphology, structure and apoptosis were investigated. Results showed that the proliferation of hMSCs was inhibited under  g condition. The abnormal gravity induced morphologic characteristics of apoptosis cells, such as cell shrinkage, membrane blebbing, nuclear chromatin condensation and margination, decreased cell viability, and increased @entity522 /7 activity. The rate of apoptosis under  g condition is up to 56.95%. The F-actin stress fibers and microtubules were disrupted under abnormal gravity condition. Under  g-condition, the expression of @entity876 at mRNA and protein levels was up-regulated more than 9- and 6 folds, respectively. The @entity12559 -a, an specific inhibitor of @entity876 , inhibited the apoptosis and prevented the disruption of cytoskeleton induced by abnormal gravity. These results implied that hMSCs were sensitive to abnormal gravity and exhibited classic apoptotic features, which might be associated with @entity876 signaling.
