摘要
目的探讨双歧杆菌对电离辐射损伤的防护作用。方法选用SPF级C57BL小鼠30只,随机分成3组(每组10只):A组:正常对照组;B组:放射损伤组;C组:双歧处理组,用双歧杆菌菌悬液灌肠28 d后,然后与放射损伤组一同进行60Coγ射线一次性全身照射,形成急性放射损伤。24 h后按不同要求采集标本,对肝组织分别进行SOD和CAT活力及MDA的含量检测;用电镜观察脊神经组织细胞的超微结构;对脾脏组织用RT-PCR检测TLR2 mRNA水平的表达;并对肾脏组织用免疫组化检测bcl-2、NF-κBp65和Cytochrome C的蛋白表达情况。结果双歧杆菌处理组肝组织中SOD和CAT水平明显高于放射损伤组(P<0.01),同时MDA明显低于放射损伤组(P<0.01);电镜结果显示:放射损伤组与双歧处理组的细胞浆、细胞核和线粒体均明显肿胀,双歧处理组同时具有早期凋亡现象;RT-PCR结果显示:双歧处理组TLR2 mRNA的表达明显高于放射损伤组;免疫组化结果显示:双歧处理组Cytochrome C的表达明显优于放射损伤组,而NF-κBp65和bcl-2则相反。结论双歧杆菌可通过清除自由基、抗膜脂质氧化、提高免疫机能和诱导细胞凋亡等方式来降低辐射对小鼠的损伤。双歧杆菌具有一定的抗辐射作用。
Objective To study the radioprotective effect of bifidobacterium on C57BL mice. Methods C57BL mice in SPF grade were divided into three groups. Mice in control group （ n = 10） were abnoml. Mice in radiation damage group（n = 10） and in bifidobacterium group（n = 10） were received radiation damage. The later were received bifidobacteria 1×10^9CFU/d by enteroclysm for 28 days. 24 hours later,mice were sacrificed and collected specimen. Superoxide dismutase,catalase, malondialdehydy in liver, TLR2 mRNA in spleen, bcl-2, NF-κBp65, Cytochrome C in kidney, and spine neurocyte microstruction were studied or measured. Results The levels of SOD and CAT significantly increased and MDA decreased in bifidobacterium group compared to radiation damage group. Electronic microgragh of spine neurocyte and neurogliocyte showed that cytoplasm,cytoblast and plastiosome were significantly engorged, and neurogliocyte apoptosised in earlier period. TLR2 mRNA increased in C group compared to B group by RT-PCR. Cytochrome C in kidney increased in C group compared to B group, but bcl-2, NF-κBp65 increased. Conclusions Bifidobacteria can degrade radiation damage by scavenging free radical, resisting membrane lipid oxidation, elevating immunity and inducing apoptosis. So bifidobacterium possess invariably radioprotective effect.
出处
《中国微生态学杂志》
CAS
CSCD
2007年第4期330-332,共3页
Chinese Journal of Microecology
