Decoction of Four Fresh Drugs protects human lymphocytes against in vitro radiation

Objective To observe the protective effect of Decoction of Four Fresh Drugs on in vitro irradiated human peripheral blood lymphocytes. Methods In vitro cultured human peripheral blood lymphocytes were divided into control group,and 3 groups with different concentrations of Decoction of Four Fresh Drugs（1%,2%,and 4%） as experimental groups.Apoptosis rate of lymphocytes was detected with a flow cytometer.Radiation resistance of lymphocyte DNA was observed by ³H-thymidine incorporation.Proliferating activity of lymphocytes in control and different experimental groups was determined by MTT assay. Results Two hours after irradiation,the activity of lymphocytes was higher in different experimental groups than in control（P＜0.05）,which increased with the concentration of Decoction of Four Fresh drugs.Five hours after irradiation,only high concentration of Decoction of Four Fresh drugs increased the activity of lymphocytes（P＜0.05）.However,10h after irradiation,Decoction of Four Fresh drugs did not increase the activity of lymphocytes.After irradiation with 1Gy and 3Gy of ⁶⁰Co,1% and 2% Decoction of Four Fresh Drugs with ³H-TdR significantly improved the radiation resistance of lymphocyte DNA（P＜0.05）.After irradiation with over 6Gy of ⁶⁰Co,no difference was found in protective effect of Decoction of Four Fresh Drugs between control and experimental groups.After irradiation with 3Gy of ⁶⁰Co,the apoptosis rate of lymphocytes was higher in control group than in experimental groups（P＜0.01）. Conclusion Decoction of Four Fresh Drugs protects human lymphocytes against irradiation in a dose-and time-dependent manner.