Hassan Amal I, Ghoneim Mona A M, Mahmoud Manal G, Asker Mohsen M S, Mohamed Saher S
Department of Radioisotopes, Nuclear Research Centre, Atomic Energy Authority, Egypt
Department of Radioisotopes, Nuclear Research Centre, Atomic Energy Authority, Egypt.
J Radiat Res. 2016 Mar;57(2):189-200. doi: 10.1093/jrr/rrv075. Epub 2015 Dec 28.
Damage to normal tissues is a consequence of both therapeutic and accidental exposures to ionizing radiation. A water-soluble heteropolysaccharide called AXEPS, composed of glucose, galactose, rhamnose and glucouronic acid in a molar ratio of nearly 1.0:1.6:0.4:2.3, respectively, was isolated from culture medium of strain Alcaligenes xylosoxidans MSA3 by ethanol precipitation followed by freeze-drying. Chemical analysis, Fourier-transform infrared (FTIR) and chromatographic studies revealed that the molecular weight was 1.6 × 10(4) g mol(-1). This study was designed to investigate the radioprotective and biological effects of AXEPS in alleviating the toxicity of ionizing radiation in female albino rats. A total of 32 female albino rats were divided into four groups. In the control group, rats were administered vehicle by tube for four weeks. The second group was administered AXEPS (100 mg/kg) orally by gavage for four weeks. Animals in the third group were exposed to whole-body γ-rays (5 Gy) and remained for 2 weeks without treatment. The fourth group received AXEPS (100 mg/kg) orally by gavage for two weeks before being exposed to whole-body γ-rays (5 Gy), then 24 h post γ-rays, they received AXEPS (100 mg/kg) in a treatment continuing till the end of the experiment (15 days after the whole-body γ-irradiation). Oral administration of AXEPS (100 mg/kg) significantly reversed the oxidative stress effects of radiation, as evidenced by the decrease in DNA damage in the bone marrow. Assessment of apoptosis and cell proliferation markers revealed that caspase-3 significantly increased in the irradiated group. Moreover, a significant decrease in the hematological constituents of peripheral blood, the chemotactic index and CD8+ T cells were observed in animals in the irradiation-only group, whereas an increase in the lymphocyte index was observed in animals in that group. In contrast, AXEPS treatment prevented these alterations. From our results, we conclude that AXEPS is a potent antioxidant and treatment agent for protection from γ-rays.
正常组织受损是治疗性和意外性电离辐射暴露的结果。一种名为AXEPS的水溶性杂多糖，由葡萄糖、半乳糖、鼠李糖和葡萄糖醛酸以摩尔比分别约为1.0:1.6:0.4:2.3组成，通过乙醇沉淀然后冷冻干燥从木糖氧化产碱杆菌MSA3菌株的培养基中分离得到。化学分析、傅里叶变换红外光谱（FTIR）和色谱研究表明其分子量为1.6×10⁴ g/mol。本研究旨在探讨AXEPS在减轻雌性白化大鼠电离辐射毒性方面的辐射防护和生物学效应。总共32只雌性白化大鼠被分为四组。对照组大鼠通过灌胃给予赋形剂四周。第二组大鼠通过灌胃口服AXEPS（100 mg/kg）四周。第三组动物接受全身γ射线（5 Gy）照射，然后未经处理持续2周。第四组在接受全身γ射线（5 Gy）照射前两周通过灌胃口服AXEPS（100 mg/kg），然后在γ射线照射后24小时，它们接受AXEPS（100 mg/kg）治疗直至实验结束（全身γ射线照射后15天）。口服AXEPS（100 mg/kg）显著逆转了辐射的氧化应激效应，骨髓中DNA损伤的减少证明了这一点。对凋亡和细胞增殖标志物的评估显示，照射组中caspase-3显著增加。此外，仅接受照射组的动物外周血血液成分、趋化指数和CD8⁺ T细胞显著降低，而该组动物的淋巴细胞指数增加。相比之下，AXEPS治疗可防止这些改变。根据我们的结果，我们得出结论，AXEPS是一种有效的抗氧化剂和γ射线防护治疗剂。
