SOD对肿瘤细胞凋亡影响和抗氧化损伤的研究:Ⅱ.SOD对荷瘤小鼠脾淋巴细胞的辐射防护效应

Studies on tumor cell apoptosis with SOD and its anti-oxidation effect II. Radio-protective effect on spleen lymphocyte of tumor-bearing mice with SOD

以受照射荷瘤小鼠为实验对象,研究外源性超氧化物歧化酶(SOD)对荷瘤小鼠脾淋巴细胞分化、增殖、亚群间调节的影响,测定了抗氧化酶活性和氧化还原产物含量,观察了SOD对荷瘤小鼠脾脏超微结构的影响,同时检测SOD对射线杀伤肿瘤细胞效应的影响。结果显示,SOD能够促进受全身照射的H22肝癌荷瘤小鼠淋巴细胞分化、增殖及亚群间调节,同时增加脾脏组织中GSH-Px、T-SOD活力和GSH含量,降低MDA含量,并提高其免疫活性;;SOD可明显减轻电离辐射对荷瘤小鼠脾淋巴细胞超微结构的破坏,并通过延迟S期时相对改变其细胞周期。实验结果提示,SOD通过清除自由基降低ROS浓度,减轻脾淋巴细胞脂质过氧化,延迟脾淋巴细胞S期时相而提高其辐射抗性,同时SOD可提高抗氧化物酶活性,并通过影响细胞凋亡信号转导途径,进而影响细胞凋亡基因的表达。

In this paper the effects of exogenous SOD on differentiation, proliferation, regulation of subpopulation of spleen lymphocytes has been studied with irradiated tumor?bearing mice. The activity of antioxidant enzymes and the contents of redoxic products have also been determined. And the effect of SOD on ultra?structure of spleen of irradiated tumor?bearing mice has been investigated meanwhile the killed effect of spleen tumor under irradiation with addition of SOD has been observed. It has been found that SOD does emphasize the differentiation, proliferation, regulation of subpopulation of spleen lymphocytes cell with radiated tumor?bearing mice and increase the activities of GSH、GPX and total?vigor of SOD while MDA decreased in spleen. It has been also found that SOD injected before or after irradiation can reduce the injury of spleen obviously and makes the tissue have higher protection from irradiation while the tumor was killed as the same as no addition of SOD. It can be deduced that lighten of lipid peroxidation occurs from the scavenge of ROS by SOD, the high protection of sleep from irradiation is because of delay to S phase of lymphocytes and increase of activity of antioxidant enzymes. The concentration change of SOD and ROS may have some influence on signal transferring pathway and gene expression of cell apoptosis.