中文摘要：

目的研究吲哚-3-甲醇（I3C）对小鼠骨髓造血细胞辐射损伤的保护作用及机制。方法（1）密度梯度离心法获得CD45.1亚型C57BL/6J小鼠骨髓有核细胞，经0mol/L、10-8mol/L~10-3mol/LI3C处理后，接受不同剂量（0Gy、1Gy、4Gy）的137Csγ-射线照射；继续培养18h后采用生物发光法检测细胞活力。（2）设空白对照组和10-6mol/LI3C组，经上述3种剂量射线照射后，接种于甲基纤维素半固体培养基中培养7d，观察骨髓粒-单核巨噬细胞集落（CFU-GM）形成情况。（3）取24只CD45.2亚型小鼠接受8Gy137Csγ-射线照射作为受体，CD45.1亚型小鼠骨髓有核细胞（供体）设空白对照组、4Gy照射组和4Gy照射+10-6mol/LI3C组。将供体与竞争者（CD45.2亚型）骨髓细胞混和后，接种于受体小鼠体内（每组8只），流式细胞术检测受体小鼠外周血细胞中供体来源的细胞比例。（4）细胞设空白对照组、10-6mol/LI3C组、1Gy照射组和1Gy照射+10-6mol/LI3C组。培养24h后收集细胞，提取蛋白后Westernblot法检测各组核因子NF-E2相关因子（Nrf2）、血红素加氧酶（HO）-1表达。结果（1）I3C浓度>10-4mol/L时出现明显的细胞毒性作用（P>0.05）；相同剂量射线照射下，10-7~10-6mol/LI3C可减轻射线对细胞的损伤；因此选取10-6mol/L为本研究I3C的实验浓度。（2）相同剂量射线照射下，10-6mol/LI3C组CFU-GM形成数量较空白对照组明显升高（P<0.05）。（3）流式细胞结果显示，4Gy照射组细胞移植后，受体小鼠外周血中供体细胞比例较对照组明显降低（P<0.05），而10-6mol/LI3C预处理的供体小鼠细胞移植后，受体小鼠中供体细胞比例较4Gy照射组升高（P<0.05）。（4）Westernblot结果显示，1Gy照射+10-6mol/LI3C组Nrf2和HO-1蛋白表达水平明显高于其他3组（P<0.05）。结论I3C可以减轻辐射引起的小鼠造血细胞损伤和功能下降，其机制可能与激活Nrf2/HO-1通路有关。

英文摘要：

Objective To investigate the protective effect of indole-3-carbinol(I3C)on radiation-induced mousebone marrow hematopoietic cell injury and the involved mechanisms.Methods(1)The bone marrow nuclear cells(BMNCs)from CD45.1subtype of C57BL/6J mice were collected by a density gradient centrifugation method.The BMNCswere pretreated with a series doses of I3C(0mol/L,10-8mol/L-10-3mol/L)and then exposed with radiation of137Csγ-ray(doses of irradiation were0Gy,1Gy and4Gy).After18-hour culturing,the bioluminescence method was used to detect thecell viability.(2)These cells were divided into control group and10-6mol/L I3C group.Both groups were received theirradiation(0Gy,1Gy and4Gy)and inoculated into the methylcellulose semi-solid culture medium to incubate7days,thecolony forming unit-granulocyte monocytes(CFU-GM)were observed.(3)Twenty-four CD45.2subtype mice used as the receptor were exposed with8Gy radiation.The CD45.1BMNCs were divided into control group,4Gy irradiation group,4Gyirradiation and10-6mol/L I3C group.Donor cells were harvested from C57BL/6J(CD45.1)mice after they received varioustreatments,and were then mixed with competitive BMNCs from C57BL/6J(CD45.2)mice.The mixed cells were transplantedinto recipient mice(8mice/group).Flow cytometry was used to analyze the proportion of donor cells in peripheral blood ofreceptor.(4)The cells were divided into control group,10-6mol/L I3C group,1Gy irradiation group,1Gy irradiation with10-6mol/L I3C group.After24-hour culturing,Western blot assay was used to detect the expression levels of nuclear factorerythroid2-related factor2(Nrf2)and hemeoxygenase-1(HO-1).Results(1)I3C showed a significant cytotoxic effect onthe BMNCs when its concentration was above10-4mol/L.10-7-10-6mol/L I3C could reduce the radiation injury of BMNCsunder the same dose of irradiation.Therefore,10-6mol/L I3C was chosen for subsequent experiments.(2)The CFU-GM wassignificantly higher in10-6mol/L I3C group than that of control group(P<0.05).(3)Results of flow cytometry showed thatthe proportion