Electromagnetic field (10??Hz, 1??mT) protects mesenchymal stem cells from oxygen-glucose deprivation-induced cell death by reducing intracellular Ca2+ and reactive oxygen species

摘要

Protective effects of electromagnetic fields (EMFs) against oxygen and glucose deprivation (OGD)-induced human mesenchymal stem cell (MSC) death were studied. Cell survival, intracellular calcium and ROS/RNS levels were measured after culturing MSCs for 3??h under OGD with or without EMF exposure. The survival rate of cells cultured under OGD condition was significantly reduced compared to control cells, while cells cultured in OGD with 10??Hz/1??mT EMF exposure had higher survival ratio than that in equivalent non-exposed cells. This protective effect of EMF was not observed at different frequency/intensity combinations such as 10??Hz/0.01??mT, 10??Hz/0.1??mT, 50??Hz/1??mT and 100??Hz/1??mT. ROS/RNS levels of cells cultured under OGD conditions significantly increased compared to the control level while 10??Hz/1??mT EMF alleviated this effect. Intracellular calcium levels in OGD group were higher than control while those in OGD plus 10??Hz/1??mT EMF group were significantly lower than OGD group. Addition of Ca2+ chelator promoted protective effects of EMF against OGD-induced MSC death. Our results suggest that 10??Hz/1??mT EMF exposure protects MSCs from OGD-induced cell death and the underlying mechanisms of the protection are reduction of intracellular levels of Ca2+ and ROS/RNS.