乳双歧杆菌V9对头孢曲松钠作用小鼠肠道菌群的变化

Effect of Bifidobacterium lactis V9 on Changes in Intestinal Microflora of Ceftriaxone Sodium-treated Mice

该研究主要探讨了乳双歧杆菌V9对头孢曲松钠作用的小鼠肠道菌群的变化。头孢曲松钠连续灌胃5 d建立小鼠肠道菌群失调的模型,然后随机分为4组,分别为模型组及低、中和高剂量组。低、中和高剂量组灌胃不同剂量乳双歧杆菌V9溶液,另设正常对照组,与模型组灌胃等体积生理盐水,连续灌胃23 d。灌胃结束后,采集小鼠的粪便进行活菌计数和16S rDNA测序,检测粪便中微生物组成及分布,测定血清中IL-1β、IL-6、TNF-α以及IL-2的含量,测定小肠及肝脏组织中SOD、MDA、GSH、GSH-Px的含量,HE染色观察小鼠小肠组织病理学变化。结果表明,灌胃乳双歧杆菌V9溶液后,中、高剂量组IL-1β、IL-6、TNF-α及IL-2的含量分别显著降低31.73、17.04、12.57及31.71 pg/mL;高剂量组小肠及肝脏组织中MDA含量显著降低(p<0.01),中、高剂量组SOD、GSH及GSH-Px均极显著升高(p<0.01)。同时,乳双歧杆菌V9使得头孢曲松钠导致的小鼠肠道菌群失调得到明显改善,粪便活菌计数显示高剂量组肠杆菌数量显著降低0.34 lg cfu/g,乳杆菌及双歧杆菌数量显著增加,分别增加0.40 lg cfu/g和0.26 lg cfu/g。拟普雷沃菌属和魏斯氏菌丰度显著降低(p<0.01)。说明乳双歧杆菌V9对由头孢曲松钠引起的肠道菌群失衡具有一定的调节作用,并调节菌群多样性。

Ceftriaxone sodium was intragastrically administered for five days to establish an enteric dysbacteriosis model of mice.Mice were randomly divided into four groups:the model group,and the low-,medium-,and high-dose groups.The low-,medium-,and high-dose groups were intragastrically administered different doses of Bifidobacterium lactis V9 solution,whereas the normal control and model groups were administered the same volume of normal saline.Twenty-three days after administration,the composition and distribution of microorganisms in the feces of the mice were detected using viable count and 16S rRNA gene sequencing.An enzyme-linked immunosorbent assay kit was used to measure the levels of interleukin(IL)-1β,IL-6,tumor necrosis factor(TNF)-α,and IL-2 in serum and the levels of SOD,MDA,GSH,and GSH-Px in the small intestine and liver.HE staining was used to observe the histopathological changes in the small intestine.Thirty days after administration,the levels of IL-1β,IL-6,TNF-α,and IL-2 in the medium-and the high-dose groups were significantly lower than those in the model group(by 31.73,17.04,12.57 and 31.71 pg/mL,respectively);the MDA content in the small intestine and liver tissues in the high-dose group was significantly lower than that in the model group(p<0.01).The SOD,GSH,and GSH-Px levels in the middle-and high-dose groups significantly increased(p<0.01).B.lactis V9 significantly ameliorated the intestinal microflora imbalance caused by ceftriaxone sodium in mice.Fecal viable count indicated that the number of Enterobacter spp.significantly reduced(by 0.34 lg CFU/g)in the high-dose group.The numbers of Lactobacillus and Bifidobacterium spp.significantly increased(by 0.40 lg cfu/g and 0.26 lg cfu/g,respectively).The abundance of bacteria in the Alloprevotella and Weissella genera decreased significantly(p<0.01).Thus,B.lactis V9 effectively ameliorated the enteric dysbacteriosis caused by ceftriaxone sodium and regulated the diversity of intestinal microbiota.