新型异黄酮T1对辐射引起的造血损伤的防护作用

Radioprotective effect of new isoflavonids(T1) on hemopoietic system of male SD rats

目的探讨新型异黄酮化合物(T1)对雄性SD大鼠由辐射引起的造血系统损伤的防护作用。方法将60只SD大鼠分为正常对照组、辐射组、T1预防组和T1治疗组,每组15只。4.5 Gy60Coγ射线一次性全身照射大鼠(正常对照组除外),T1预防组和T1治疗组大鼠分别在照射前和照射后按剂量为10 mg/kg腹腔注射T1溶液,辐射组在受照后不给予任何处理。动态观察各组大鼠受照前后体质量和外周血WBC 4周内的变化,比较照后1周和4周各组骨髓的病理学变化,并利用比色法测量照后1周各组肝脏组织抗氧化酶的活性。结果受照大鼠的体质量与正常对照组相比,体质量明显减轻(P<0.05);在照后第1、4、5天,T1预防组和T1治疗组的WBC明显高于辐射组(P<0.05),在T1预防组和T1治疗组间差异不明显,从第6天开始,WBC进入恢复期,除正常对照组外,各组WBC无明显差异(P>0.05);受照后1周,辐射组骨髓造血细胞明显减少伴脂肪组织显著增生,T1预防组和T1治疗组损伤相对较轻;在T1预防组,肝脏匀浆CAT、GSH-Px活力较辐射组明显升高,MDA水平明显降低(4.06±0.19vs5.61±0.46,P<0.05)。结论 T1可以减缓照后WBC的下降速度,使WBC的回升时间提前,并对辐射造成的骨髓损伤具有一定的防护作用,其机制可能与消除体内过量有害自由基有关。

Objective To identify the radioprotective effect of an isoflavonids（T1）,three hydroxyl isoflavone（or genistein） on the hemopoietic system of male SD rats.Methods Sixty rats were weighed and randomly divided into 4 groups,control（5%DMSO was intraperitoneally injected at a dose of 10 mg/kg,once per day for 3 d）,radiation group（5% DMSO was intraperitoneally injected at a dose of 10 mg/kg,once per day for 3 d,and then 4.5 Gy 60Co γ-ray irradiation was given in 4 h after last injection）,T1 prevention group（intraperitoneal injection of T1 at a dose of 10 mg/kg was given once per day for 3 d,and then the irradiation was given as irradiation group）,and T1 treatment group（First intraperitoneal injection of T1 at a dose of 10 mg/kg was given in 4 h after irradiation,and then for another 2 d）.The dynamic weight before and after irradiation and blood WBC count were measured for 4 consecutive weeks after irradiation.Then pathological changes in the bone marrow were observed in the first week and the fourth week after radiation.Antioxidase activity in the liver were measured by colorimetry in a week after radiation.Results Compared with control group,no significant weight loss was observed in the other 3 groups after radiation（P0.05）.In 1,4 and 5 d after radiation,the blood WBC count in T1 preventive group and T1 treatment group were significantly higher than those in radiation group（P0.05）,and there was no significant difference between T1 preventive group and T1 treatment group.The blood WBC count in each group（except the control group） had no difference in 6 d after radiation（P0.05） among these groups.Bone marrow hematopoietic cells were decreased significantly with adipose tissue hyperplasia in radiation group in a week after radiation,while relatively minor damages were seen in T1 preventive group and T1 treatment group.Over 7 d after irradiation,MDA content of T1 prevention group were much lower than those in radiation group（4.06±0.19 vs 5.61±0.46,P0.05）,meanwhile,CAT and GSH-Px activities were much higher（P0.05）,respectively.Conclusion T1 can significantly slow down the descent speed of WBC after irradiation and bring forward the recovery time.In addition,T1 plays an important role in radiation protection against the hemopoietic damage,and its mechanism might be related to eliminating the excessive free radicals.