Objective To investigate the protective effect of indole-3-carbinol (I3C) on radiation-induced mouse bone marrow hematopoietic cell injury and the involved mechanisms. Methods (1) The bone marrow nuclear cells (BMNCs) from CD45.1 subtype of C57BL/6J mice were collected by a density gradient centrifugation method. The BMNCs were pretreated with a series doses of I3C (0 mol/L, 10-8 mol/L-10-3 mol/L) and then exposed with radiation of 137Csγ-ray (doses of irradiation were 0 Gy, 1 Gy and 4 Gy). After 18-hour culturing, the bioluminescence method was used to detect the cell viability. (2) These cells were divided into control group and 10-6 mol/L I3C group. Both groups were received the irradiation (0 Gy, 1 Gy and 4 Gy) and inoculated into the methylcellulose semi-solid culture medium to incubate 7 days, the colony forming unit-granulocyte monocytes (CFU-GM) were observed. (3) Twenty-four CD45.2 subtype mice used as the receptor were exposed with 8 Gy radiation. The CD45.1 BMNCs were divided into control group, 4 Gy irradiation group, 4 Gy irradiation and 10-6 mol/L I3C group. Donor cells were harvested from C57BL/6J (CD45.1) mice after they received various treatments, and were then mixed with competitive BMNCs from C57BL/6J (CD45.2) mice. The mixed cells were transplanted into recipient mice (8 mice/group). Flow cytometry was used to analyze the proportion of donor cells in peripheral blood of receptor. (4) The cells were divided into control group, 10-6 mol/L I3C group, 1 Gy irradiation group, 1 Gy irradiation with 10-6 mol/L I3C group. After 24-hour culturing, Western blot assay was used to detect the expression levels of nuclear factor erythroid 2-related factor 2 (Nrf2) and hemeoxygenase-1 (HO-1). Results (1) I3C showed a significant cytotoxic effect on the BMNCs when its concentration was above 10-4 mol/L. 10-7-10-6 mol/L I3C could reduce the radiation injury of BMNCs under the same dose of irradiation. Therefore, 10-6 mol/L I3C was chosen for subsequent experiments. (2) The CFU-GM was significantly higher in 10-6 mol/L I3C group than that of control group (P<0.05). (3) Results of flow cytometry showed that the proportion of donor cells in receptor was significantly higher in 4 Gy irradiation group than that of control group, which decreased the engraftment capability of irradiated HSCs (P<0.05), although the engraftment capability of irradiated HSCs improved after 10-6 mol/L I3C treatment. (4) I3C significantly enhanced the increased protein expression of Nrf2 and HO-1 caused by radiation (P<0.05). Conclusion I3C has a protective effect on hematopoietic cells following radiation-induced injury, which may be related with activating the Nrf2/HO-1 signal pathway.

Objective To investigate the protective effect of 3,3′-diindolylmethane (DIM) on radiation-induced injury in mouse hematopoietic system. Methods Thirty C57BL/6 mice were randomly divided into control group, 2 Gy irradiation group and 2 Gy irradiation+DIM group (n=10 for each group). Mice of control group received sham irradiation, and the other two groups accepted 2 Gy 137Cs γ-ray total body irradiation. Mice in 2 Gy irradiation +DIM group were intraperitoneally injected 75 mg/kg DIM 30 min before irradiation. Mice of other two groups were treated with reference solution. After 7 d and 15 d of 2 Gy irradiation, the peripheral blood samples were collected to count the number of bone marrow nuclear cells (BMNCs). The level of reactive oxygen species(ROS) was measured by DCFH-DA. The levels of colony forming units-granulocyte-macrophage (CFU-GM) were also detected. Results The numbers of white blood cell (WBC), platelet count (PLT), BMNCs and CFU-GM were significantly decreased and the ROS level of bone marrow cells increased significantly in the irradiated group than those of control group (P<0.05). Compared to 2 Gy irradiation group, the numbers of WBC, PLT, BMNCs and CFU-GM were significantly increased in 2 Gy irradiation +DIM group, and the level of ROS was decreased significantly (P<0.05). Conclusion DIM has a protective effect on hematopoietic cells following radiation-induced injury, which may be related with the decreased ROS level.

Objective To explore the effect of low calorie metabolism on the survival of HeLa cells exposed to X-rays,and the influence of starvation on the antioxidative factors in the blood of rats after irradiation.Methods MTT method was used to evaluate the impact of different concentration glucose on the proliferation of HeLa cells.Colony formation assay was employed to detect the influence of glucose ( 1,5,10 and 25 mmol/L) on radiosensitivity of HeLa cells. Flow cytometry assay was used to analyze distribution of cell cycle and apoptosis.60 male SD rats were randomly divided into 6 groups with 10 rats each.Rats in every two groups were fed ad libitum,fasted for 24 h and fasted for 48 h,respectively.Rats in one group of each approach were respectively exposed to whole-body X-rays at 11 Gy. At 2 h after irradiation,all of rats were sacrificed and their venous blood was collected.Elisa kits were used to detect superoxide dismutase (SOD) and total antioxidant capacity (T-AOC).Results An increased viability was observed in HeLa cells treated with the glucose at low concentration ( ＜25 mmol/L),while HeLa cell growth was inhibited by glucose at doses of ＞25 mmol/L. Relevant to cells treated with 1 mmoL/L glucose,SERs (sensitive enhancement ratio) in cells exposed to 5,10 and 25 mmol/L glucose were 1.07,1.10 and 1.23,respectively. A reduction of G2/M and S arrests and apeptosis caused by 6 Gy X-ray irradiation were observed [(49.68 ±1.88)％ and (35.54±1.45)％ at G2/M phase,(16.88 ±1.22)％ and (10.23 ±1.65)％ atS phase,t=10.42,5.61,P＜0.05]and in the cells treated with 1 mmol/L glucose compared with cells treated with 25 mmol/L glucose [ ( 25.50 ± 0.95 ) ％ and (7.56 ± 1.07 ) ％,t =21.72,P ＜0.05 ].Without irradiation,calorie restriction exhibited a negligible influence on SOD and T-AOC in rats.However,after 11 Gy irradiation,compared with rats fed ad libitum,the levels of SOD and T-AOC were significantly increased in rats with calorie restriction ( t =40.32,42.78, P ＜ 0.05 ).Conclusions Calorie restriction has a certain radioprotective effect in vivo and in vitro.

Aim and Methods To investigate the effect of UCN-01(7-hydroxystaurosporine) on cell migration and invasion ability of DU-145, an invasive human prostate cancer cell line.Results It was found that UCN-01 at non-cytotoxic doses (100 nmol· L-1) significantly inhibited prostate cancer DU-145 cell invasion and migration behaviors.Moreover, this anti-invasion and migration activity of UCN-01 was associated with an up-regulation of cell adhesion molecule E-cadherin. Conclusion These results indicate for first time that UCN-01 inhibits the invasion and migration of human prostate cancer cells.Thus, clinical application of UCN-01 may contribute to the potential benefit for suppression of prostate cancer invasion and metastasis.

Objective To observe the effect of sesamol on the hematopoietic system in mice exposed to 4 Gy irradiation. Method Twenty C 57 BL/6 mice were randomly divided into control group, sesamol group, irradiated group and irradiated+sesamol group (n=5). Mice of control and sesamol group received sham irradiation, and the rest exposed to 4 Gy total body irradiation, dose rate 1.01 Gy/min. Mice in sesamol group and irradiated+sesamol group received a dose of 10 mg/kg sesamol administered by gavage every day for 7 days after irradiation exposure. Mice of other two groups were treated with vehicle solution. After 4 Gy irradiation 7 day, the peripheral bloods were collected. The levels of colony forming units-granulocyte-macrophage (CFU-GM) were detected. Results Compared to irradiation group, the level of WBC、cell count of BMNCs and CFU-GM significantly decreased in the irradiated mice, decreased in the irradiated mice (P<0.05). Compared to irradiation group, cell count of BMNCs and CFU-GM in the irradiated+sesamol group increased significantly (P<0.05). Conclusion Sesamol has a certain impact on the radiation-induced changes in hematopoietic system. The mechanism need to be further explored.

Objective To study the effect of sanguinarine on the growth and radiosensitivity of ovarian cancer SK-OV-3 cells.Methods Cell growth was determined by MTT and clonogenic assay.Cell cycle analysis was performed by flow cytometry assay.The cell apoptosis was analyzed by Annexin V/PI assay.Results Sanguinarine inhibited SK-OV-3 cell growth in a dose-and time-dependent fashion and its IC50 values were 3.02 and 1.11 μmol/L at 24 and 48 h,respectively. Sanguinarine also significantly triggered a sub-G1 peak,an indicator of apoptosis,and caused a G0/G1 arrest.Furthermore,the cell apoptosis induced by X-irradiation was significantly increased at 6 Gy when the cells were pre-treated with sanguinarine,in which the early apoptotic population increased from 10.28％ to 43.28％ (t =19.41,P ＜0.01 ) and the late apoptotic population increased from 20.26％ to 30.80％ ( t =8.78,P ＜ 0.01 ).The multi-target click model was used to fit survival curves and the SER of sanguinarine treatment approached to 1.625 at the dose of D0. Conclusions Sanguinarine could inhibit SK-OV-3 cell growth by inducing apoptosis and cell cycle arrest and enhance cell radiosensitivity at low doses.

Objective To investigate the protective effect of theaflavins on thymus injury caused by total body irradiation (TBI).Methods Twenty-five C57BL/6 mice were randomly divided into 5 groups:control group,4 Gy TBI group,4 Gy TBI + 25 mg/kg theaflavins group,4 Gy TBI + 50 mg/kg theaflavins group and 4 Gy TBI + 100 mg/kg theaflavins group.Thymus index and total number of thymocytes were detected at the 14th d post-irradiation to determine the optimal dose of theaflavins.According to this optimal dose,32 C57BL/6 mice were randomly divided into 4 groups:control group,theaflavins group,4 Gy TBI group and 4 Gy TBI + theaflavins group.Thymus histomorphology,CD4CD8 T cell subsets,and reactive oxygen species (ROS) in thymocytes were examined at the 14th d post-irradiation.Results The irradiated thymus exhibited decreased thymus index and total number of thymocytes (P ＜ 0.05),aberrant histomorphology and T cell subsets (P ＜ 0.05),and increased ROS level in thymocytes (P ＜ 0.05).Compared with 4 Gy TBI group,the thymus index and total number of thymocytes were significantly increased in 4 Gy TBI + 50 mg/kg theaflavins group (P ＜ 0.05).The total number of thymocytes was significantly higher in 4 Gy TBI + 50 mg/kg theaflavins group than that in 4 Gy TBI + 25 mg/kg theaflavins group (P ＜ 0.05).Therefore,50 mg/kg theaflavins was chosen as the optimal dose for subsequent experiments.Moreover,the aberrant histomorphology of irradiated thymus was alleviated by theaflavins.A decline in the percentage of CD4-CD8-T cells and an elevation of CD4+CD8-and CD4+CD8+ T cells were found in irradiated mice administered with theaflavins (P ＜ 0.05).Compared with 4 Gy TBI group,the ROS level was significantly decreased in 4 Gy TBI + theaflavins group (P ＜ 0.05).Conclusion Theaflavins exhibits a protective effect on radiation-induced thymus injury.

Objective To observe the protective effect of anthocyanin on irradiation induced bone marrow c-kit positive cell injury, and further explore its possible mechanism. Methods Mouse bone marrow c-kit positive cells were collected by cell sorting method. There were 2 groups: control group and anthocyanin group, which were sub-divided into three groups and received 0 Gy, 1 Gy and 4 Gy irradiation respectively. The control group was added 700μL cell suspension and an equal volume of serum-free hematopoietic stem/progenitor cell culture medium. The 2 × 10-5 mol/L anthocyanin was co-cultured with mouse bone marrow c-kit positive cells of anthocyanin group half an hour before irradiation exposure, then cells were cultured for 18 hours under the conventional culture conditions (37℃,5%CO2). Mouse c-kit positive cell viability was measured by bioluminescence, and which was reflected by relative light units (RLU). The ability of colony-forming units was reflected by CFU-GM. The reactive oxygen species (ROS) level and mean fluorescence intensity (MFI) ofγ-H2AX were detected by flow cytometry. Results Compared to un-irradiated control group, the cell viability and the number of CFU-GM were decreased significantly, while the ROS level and MFI ofγ-H2AX were increased in c-kit positive cells irradiated with 1 Gy and 4 Gy (P<0.05). Compared to 1 Gy and 4 Gy irradiation groups, c-kit positive cell viability and the number of CFU-GM were increased, the ROS level and MFI of γ-H2AX were decreased in anthocyanin group (P < 0.05). Conclusion Anthocyanin exhibits a promising protective effect on radiation-induced bone marrow c-kit positive cell injury, which may be related to the alleviating ROS and DNA damage in bone marrow cells.

Objective To investigate the protective effect of hydrogen-rich water (HRW) on radiation-induced hematopoietic stem and progenitor cells (HSPCs) injury.Methods Totally 32 C57BL/6 mice were randomly divided into four groups with 8 mice in each group,including control,HRW,radiation and radiation + HRW.Mice in HRW and radiation + HRW groups received 0.5 ml hydrogen-rich water per day by intragastric administration 5 min before irradiation until 7 d post-irradiation.Mice in other groups received 0.5 ml distilled water.Mice in radiation and radiation + HRW group were irradiated with 2 Gy of total body irradiation.Bone marrow cells were isolated at 15 d post-irradiation,and LSK cells were examined for the percentage of hematopoietic stem and progenitor cells,the ability of colony formation and reconstitution,reactive oxygen species (ROS) levels and cell apoptosis.Results Compared with radiation group,the percentages of hematopoietic progenitor cells and LSK cells,colony number of bone marrow cells were significantly increased in radiation + HRW group (t =-4.935,-7.898,5.488,P ＜ 0.05).An elevation of donor chimerism was also found in recipient mice administered HRW after competitive bone marrow transplantation (t =-12.769,P ＜ 0.05).Compared with radiation group,the ROS levels and cell apoptosis in LSK cells were significantly decreased (t =4.380,3.954,P ＜ 0.05).Conclusions Hydrogen-rich water exhibited a protective effect on radiation-induced HSPCs injury.

Objective To investigate the effect of ethanol on radiosensitivity of human breast cancer MCF-7 cells.Methods Human breast cancer MCF-7 cells were divided into four groups including control group,ethanol treatment group,X-ray exposed group,and ethanol combined with X-ray group.Clonogenic assay was used to determine cell survival.Flow cytometry was employed to analyze cell cycle progression.Annexin V-FITC kit was used to determine cell apoptosis induction.Results Ethanol(50 and 100 mmol/L,50 h)had no influence on MCF-7 cell growth( t =0.82,1.15,P ＞0.05 ).The radiosensitivity of MCF-7 cells was reduced when the cells were pretreated with 50 mmol/L ethanol (t =4.15,P ＜0.05)and 100 mmol/L ethanol ( t =10.28,P ＜ 0.05 ) for 2 h. Compared with irradiation with X-ray alone,ethanol treatment decreased G2/M phase arrest(t =7.18,P ＜0.05) and sub-G1population(an indicator of apoptosis induction) ( t =5.39,P ＜ 0.05).A decrease of advanced and early apoptosis in the cells pretreated with ethanol was also confirmed by Annexin V-FITC apoptosis assay( t =4.86,7.59,P ＜ 0.05 ).Conclusions Ethanol causes radioresistance in human breast cancer MCF-7 cells,where the decreases of radiation-induced G2/M phase arrest and apoptosis may be involved.