Study of ironizing radiation sensitivity decrease of stem cell induced by 635 nm low level laser / 国际生物医学工程杂志

ABSTRACT

Objective To study the radioresistance increased by low level laser irradiation (LLLI) in stem cells.Methods Umbilical cord mesenchymal stem cells (UC-MSCs) were divided into control group and experimental groups (LLLI only,γ-ray irradiation only and LLLI combined with γ-ray irradiation groups).635 nm (10 mW/cm2,12 J/cm2) laser irradiation was applied using for 3 days (twice a day),and cells were exposed in 2 Gy dose γ-ray irradiation on the third day.DNA injury was detected by alkaline single cell gel electrophoresis,reactive oxygen species (ROS),superoxide dismutase (SOD) and catalase (CAT) activity were valued using detection kits.Results DNA injury in LLLI combined with γ-ray irradiation group was lower than that in γ-ray irradiation exposed group,activity of oxidation stress kinases was enhanced,and level of ROS was inhibited.Conclusions Ironizing radioresistance of UC-MSCs can be increased after treatment of 635 nm LLLI,which will induce the radiation sensitivity of transplanting cells.