-
[show abstract]
[hide abstract]
ABSTRACT: Abstract It has been reported that carboxyfullerene (C3) exhibits a strong free radical scavenging capacity, which plays a critical role in radiation damage. We hypothesized that C3 is an effective radioprotective agent. In this study, we demonstrated that C3 effectively scavenged hydroxyl radical in a cell-free Fenton system and C3 showed no obvious toxicity for cultured cells. Different concentrations (100-400mg/L) of C3 pretreatment effectively protected AHH-1 cells from radiation-induced apoptosis, by about 2 folds, while only 100mg/L C3 reduced apoptosis rate of HIEC cells. C3 also alleviated DNA damage detected by comet assay at 0, 4 and 8h after irradiation. It was found that 75% mice were protected from 7.2Gy γ-irradiation induced death when 100mg/kg C3 was administered prior to irradiation, but no change was observed for the survival time of mice who died. We also found that C3 attenuated radiation-mediated decreases in endogenous antioxidants such as SOD and GSH and reduced the level of MDA. In conclusion, these data showed that C3 effectively protected cells and mice from radiation injury, thus indicating the potential of C3 as a safe and effective radioprotectant.
Free radical research 01/2013; · 2.22 Impact Factor
-
Cong Liu, Chuanfeng Zhou,
Fu Gao,
Shengyun Cai,
Chao Zhang,
Luqian Zhao,
Fang Zhao,
Fei Cao,
Jing Lin,
Yanyong Yang,
Jin Ni,
Jun Jia,
Wei Wu,
Li Zhou,
Jianguo Cui,
Wei Zhang,
Bailong Li,
Jianming Cai
-
Yanyong Yang,
Bailong Li,
Cong Liu,
Yunhai Chuai,
Jixiao Lei,
Fu Gao,
Jianguo Cui,
Ding Sun,
Ying Cheng, Chuanfeng Zhou,
Jianming Cai
[show abstract]
[hide abstract]
ABSTRACT: Radiation often causes depletion of immunocytes in tissues and blood, which results in immunosuppression. Molecular hydrogen (H2) has been shown in recent studies to have potential as a safe and effective radioprotective agent through scavenging free radicals. This study was designed to test the hypothesis that H2 could protect immunocytes from ionizing radiation (IR).
H2 was dissolved in physiological saline or medium using an apparatus produced by our department. A 2-[6-(4'-hydroxy) phenoxy-3H-xanthen-3-on-9-yl] benzoate (HPF) probe was used to detect intracellular hydroxyl radicals (•OH). Cell apoptosis was evaluated by annexin V-FITC and Propidium iodide (PI) staining as well as the caspase 3 activity. Finally, we examined the hematological changes using an automatic Sysmex XE 2100 hematology analyzer.
We demonstrated H2-rich medium pretreatment reduced •OH level in AHH-1 cells. We also showed H2 reduced radiation-induced apoptosis in thymocytes and splenocytes in living mice. Radiation-induced caspase 3 activation was also attenuated by H2 treatment. Finally, we found that H2 rescued the radiation-caused depletion of white blood cells (WBC) and platelets (PLT).
This study suggests that H2 protected the immune system and alleviated the hematological injury induced by IR.
Medical science monitor: international medical journal of experimental and clinical research 04/2012; 18(4):BR144-8. · 1.70 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Recent studies suggest that mangiferin aglycone (norathyriol) has great potential as a novel radioprotector without any known toxic side effects. In this study, we assessed the protective effects of mangiferin aglycone against radiation-induced injuries on normal human intestinal epithelial cells (HIECs), while using mangiferin as a reference compound. The in vitro experiments showed that pretreatment of either mangiferin aglycone or mangiferin could inhibit cytotoxic effects of ionizing irradiation (IR) on HIECs. Cellular changes were estimated by measuring cell viability, clonogenic surviving rate, and apoptotic rate. Compared to mangiferin, we found mangiferin aglycone had greater radioprotective effects of mangiferin aglycone on HIECs. It has been demonstrated that the cytotoxicity of ionizing radiation relates to its capacity to induce DNA damage. In view of this, we monitored DNA double-strand breaks (DSBs) using γH2AX foci formation to test whether mangiferin aglycone and mangiferin could modulate genotoxic effects of radiation. It shows that mangiferin aglycone could eliminate 46.8% of the total DSBs of the cells exposed to 2 Gy IR, which is significantly better than mangiferin. Complementing earlier results from our group, it appears possible to conclude that mangiferin aglycone presents potential useful effects on IR-induced damage and may be a better radioprotective agent than mangiferin therapeutically.
Journal of Cellular Biochemistry 03/2012; 113(8):2633-42. · 2.87 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Bone marrow is a major site of radiation injury. The extreme sensitivity of bone marrow cells to genotoxic stress largely determines the adverse side effects of radiation. CpG-oligodeoxynucleotide (ODN) is known to be radioprotective in extramedullary hemopoiesis, but its effect on bone marrow hemopoiesis remains unknown. In this study, we investigated whether CpG-ODN ameliorated hemopoiesis radiation injury when administered after total-body irradiation (TBI). Mice were treated with 50 μg of CpG-ODN via intraperitoneal injection (i.p) 30 min., 24 and 48 hr after TBI. Our results show that CpG-ODN was able to mediate the activation of nuclear factor κB (NF-κB) via degradation of inhibitor NF-κB (IκB-α), and some oxidative stress parameters (malondialdehyde, glutathione and superoxide dismutase) showed significant differences between the radiation control group and the radiation and administration of CpG-ODN group. White blood cell count, bone marrow cell count and bone marrow histological examination indicated that CpG-ODN minimized bone marrow damage induced by radiation. Exogenous colony-forming unit-spleen count indicated that CpG-ODN reduced primitive hemopoietic stem cell damage and reconstituted the hemopoietic system after TBI. The survival of mice was also enhanced after various levels of TBI. The calculated dose reduction factor was 1.2. Thus, we conclude that CpG-ODN may contribute to the amelioration of hemopoiesis radiation injury.
Basic & Clinical Pharmacology & Toxicology 03/2011; 109(1):11-6. · 2.18 Impact Factor
-
Cong Liu, Chuanfeng Zhou,
Fu Gao,
Shengyun Cai,
Chao Zhang,
Luqian Zhao,
Fang Zhao,
Fei Cao,
Jing Lin,
Yanyong Yang,
Jin Ni,
Jun Jia,
Wei Wu,
Li Zhou,
Jianguo Cui,
Wei Zhang,
Bailong Li,
Jianming Cai
[show abstract]
[hide abstract]
ABSTRACT: MiR-34a, a direct target of p53, has shown to exert potent anti-proliferative effects. It has also been found that miR-34a can be induced by irradiation in vitro and in vivo. However, the relationship between miR-34a and radio-sensitivity, and its potential diagnostic significance in radiation biology, remain unclear. This study found that differing responses to ionizing radiation (IR) of young and adult mice were related to miR-34a. First, we found that miR-34a could be induced in many organs by radiation of both young and adult mice. However, the level of miR-34a induced by young mice was much higher when compared to adult mice. Next, we found that miR-34a played a critical role in radio-sensitivity variations of different tissues by enhancing cell apoptosis and decreasing cell viability. We also found that the induction of miR-34a by radiation was in a p53 dependent manner and that one possible downstream target of miR-34a that lead to different radio-sensitivity was the anti-apoptosis molecular Bcl-2. However, over-expression of miR-34a and knockdown of Bcl-2 could significantly enhance the radio-sensitivity of different cells while inhibition of miR-34a could protect cells from radiation injury. Finally, we concluded that miR-34a could be stable in serum after IR and serve as a novel indicator of radiation injury. Taken together, this data strongly suggests that miR-34a may be a novel indicator, mediator and target of radiation injury, radio-sensitivity and radioprotection.
International journal of biological sciences 01/2011; 7(2):221-33. · 2.70 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Ionizing radiation (IR) is a well-known carcinogen, however the mechanism of radiation induced thymic lymphoma is not well known. Moreover, an easy and effective method to protect mice from radiation induced thymic lymphoma is still unknown. Hydrogen, or H(2), is seldom regarded as an important agent in medical usage, especially as a therapeutic gas. Here in this study, we found that H(2) protects mice from radiation induced thymic lymphoma in BALB/c mice.
International journal of biological sciences 01/2011; 7(3):297-300. · 2.70 Impact Factor
