不同剂量^(60)Co-γ射线对TM3细胞的损伤效应

Effect of different doses of ^(60)Co γ-radiation on TM3 cells

目的:对不同剂量6 0Co-γ射线下TM 3细胞的损伤进行细胞生物学行为、转录层面的分析。方法:TM 3细胞分4组,包括3个6 0Co-γ射线照射组(3、6、9 Gy)及对照组(不照射)。于2 4、4 8、7 2 h观察各组细胞凋亡情况(流式细胞法)、氧化损伤(ELISA)、睾酮合成关键因子(St AR、P450scc、P450c17及3β-HSD)的m R NA表达(实时定量PCR法)。于24、48、72、96、120、144 h,观察细胞增殖情况(MTS法)。结果:第24、72 h,各照射组细胞凋亡率均高于对照组(P<0.008);MTS实验中,第144、120 h,各照射组OD490值均低于对照组(P<0.008);第24,48,72 h,3 Gy组8-OHd G浓度与对照组相比无差异(P>0.008),而9 Gy组高于对照组(P<0.008);在72 h,各照射组St AR、P450scc、3β-HSD m RNA表达均低于对照组(P<0.008),而P450c17的表达在3 Gy组中无显著改变,在6 Gy组中高于对照组,在9 Gy组中低于对照组。结论:6 0Co-γ射线使TM 3细胞凋亡增加、细胞增殖能力下降。6 Gy、9 Gy照射可以导致TM3细胞DNA的氧化损伤。辐照导致TM3细胞中St AR、P450scc、3β-HSD m RNA表达下降。6 Gy的照射使P450c17 m RNA表达上升,9 Gy使之下降。

Objective：To analyze the impairment of TM3 cells induced by 60 Co γ radiation on cytobiological behaviors and transcriptional change.Methods：TM3 cells were divided into four groups,including three groups exposed to different doses of 60 Co γ radiation（3,6,9 Gy） and one control group without exposure.At 24,48,72 h,cell apoptotic rate of different groups was measured by l owcytometry;oxidative damage was measured by ELISA;m RNA expression of the key factors in the synthesis of testosterone（St AR,P450 Scc,P450c17,3β-HSD） was measured by q PCR.At 24,48,72,96,120,144 h,cell proliferation was measured by MTS.Results：At 24,72 h,apoptotic rate of all exposed groups was obviously higher than that of the control group（P〈0.008）;in MTS assay,at 144,120 h,the OD490 value of all exposed groups was lower than that of the control group（P〈0.008）.At 24,48,72 h,no signii cant dif erence of 8-OHd G level was observed between 3 Gy group and control group（P〈0.008）;8-OHd G level of the 9 Gy group was higher than that of the control group（P〈0.008）.At 72 h,the m RNA expression of St AR,P450 scc and P450 scc in all exposed groups was down-regulated,as compared to the control group（P〈0.008）.However,the m RNA expression of P450c17 in 3 Gy group had no dif erence from that of the control group.It was up-regulated in 6 Gy Group and down-regulated in 9 Gy Group.Conclusion：60 Co γ radiation induced cell apoptosis and decreased cell proliferation in TM3 cells.A single dose of 6 or 9 Gy caused oxidative damage in TM3 cells.Radiation down-regulated the m RNA expression of the key factors of testosterone synthesis,including St AR,P450 scc and 3β-HSD.6 Gy radiation increased the P450c17 expression level,while 9 Gy radiation decreased it.