诺丽多糖对电离辐射损伤小鼠的防护作用及对肠道菌群的影响

Protective Effect of Noni Polysaccharide on Ionizing Radiation Injury Mice and Its Effect on Intestinal Microbiota

目的:探讨诺丽多糖对小鼠电离辐射损伤的防护和肠道菌群的调节作用。方法:将50只KM雄性小鼠随机分为正常组、模型组、诺丽多糖低剂量组、中剂量组和高剂量组,采用医用电子直线加速器进行全身一次性X射线辐照建立急性辐射损伤小鼠模型。观察辐射后小鼠的生存质量,检测辐射后72 h小鼠血清和肝脏组织相关生化指标;通过小鼠粪便的16S rRNA测序分析肠道菌群多样性。结果:诺丽多糖能够改善辐射损伤小鼠的生存质量,提高脏器指数、小鼠外周血白细胞(WBC)数、脾结节数、骨髓DNA含量,降低骨髓嗜多染红细胞微核(MN-PCE)率,提高血清及肝脏中的抗氧化酶过氧化氢酶(CAT)、超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH-Px)的活性,降低丙二醛(MDA)含量。与MC组相比,诺丽多糖高剂量组外周白细胞数和脾结节数分别增加了46.85%和38.23%,骨髓DNA含量提高了51.95%,MN-PCE降低率为38.84%,并对辐射后小鼠的氧化应激均有不同程度的改善。此外,诺丽多糖能够促进辐射损伤小鼠肠道菌群向有益于宿主健康的方向生长,同时促进益生菌的生长并抑制有害菌的定植,恢复电离辐射引起的肠道菌群变化。结论:诺丽多糖对X射线所致的电离辐射损伤小鼠具有明显的防护作用,且对辐射造成的肠道菌群紊乱有一定的恢复作用。

Objective:This study was to investigate the protective effect of Noni polysaccharides on ionizing radiation injury and its regulation of intestinal flora in mice.Methods:Fifty KM male mice were randomly divided into normal group,model group,noni polysaccharide low-dose group,noni polysaccharide medium-dose group and Noni polysaccharide highdose group.The whole body of the mice was irradiated by the medical electron linear accelerator,thus establishing acute radiation-damaged mice model.Subsequently,survival quality of mice after irradiating was observed,and related biochemical indicators of serum and liver tissue of mice after irradiating for 72 h were detected.Furthermore,16S rRNA sequencing of mouse feces was performed to analyze diversity of intestinal flora.Results:Noni polysaccharides could improve survival quality of radiation-damaged mice,and increase organ index,peripheral blood leukocyte(WBC)number,spleen nodule number,bone marrow DNA content.Moreover,noni polysaccharides could reduce the rate of bone marrow polychromatic erythrocyte micronucleus(MN-PCE),and increase the activities of antioxidant enzymes catalase(CAT),superoxide dismutase(SOD)and glutathione peroxidase(GSH-Px)in serum and liver,and reduce malondialdehyde(MDA)content.Compared with the MC group,the increase rate of peripheral white blood cell count and number of splenic noduleswas 46.85%,38.23%,and the content of bone marrow DNA increased by 51.95%,the reduction rate of MN-PCE was 38.84%of Noni polysaccharide high-dose group.Meanwhile,the oxidative stress of mice after irradiating had improvement in different degree of Noni polysaccharide.Additionally,Noni polysaccharides could promote the growth of intestinal flora of radiation-damaged mice in a direction of beneficial to host health.Meanwhile,Noni polysaccharides could accelerate the growth of probiotics and inhibit the colonization of harmful bacteria,and recover the changes of intestinal flora caused by ionizing radiation.Conclusion:Noni polysaccharides exhibited obvious protective effect on ionizing radiation-damaged mice caused by X-ray,and showed certain restoring effect on intestinal flora disturbance caused by radiation.