益生菌制剂对抗生素诱导腹泻模型小鼠肠道菌群的恢复

The Effects of Probiotics on the Restoration of Intestinal Microflora in a Mouse Model of Antibiotic-induced Diarrhea

为了评价益生菌制剂对腹泻模型小鼠肠道菌群的恢复,现采用22.4 g/(kg·d)氨苄青霉素灌胃构造小鼠腹泻模型,其中空白对照组灌胃等量生理盐水。造模成功后,用低、中、高不同剂量的益生菌制剂对小鼠治疗恢复,治疗14 d后,观察益生菌制剂对小鼠稀便率、稀便级和腹泻指数的影响。无菌取治疗后0、7、14 d的小鼠粪便进行分析,分别采用平板计数和DGGE技术检测肠道目标菌群变化。停用益生菌制剂后,无菌采取0、7、14 d的粪便样品,荧光定量PCR定量检测外源益生菌。结果表明,益生菌制剂不仅能改善小鼠的腹泻情况,促进腹泻小鼠的生长,还对腹泻小鼠肠道菌群结构具有显著恢复作用;荧光定量PCR检测结果表明外源益生菌嗜酸乳杆菌NCFM、乳双歧杆菌Bi-07和鼠李糖乳杆菌HN001在停止灌胃益生菌制剂后可定殖存活,但随着时间推移呈一定衰减的趋势。

In order to evaluate the effects of probiotics on the restoration of intestinal microflora in a mouse model of diarrhea, 22.4 g/（kg·d） ampicillin was administered by gavage to construct the mouse model of diarrhea, and the blank control group was given saline at the same dosage. After the model was successfully constructed, low-, medium-, and high-dose probiotics were used to treat the mice to restore their intestinal microflora. The effect of probiotics on the loose stool rate, degree of loose stool, and diarrhea index were observed after 14 days of treatment. The aseptically collected fecal samples of mice at days 0, 7, and 14 after treatment were analyzed, and changes in the target intestinal flora were determined using denaturing gradient gel electrophoresis（DGGE） and plate counting methods. After the completion of probiotic treatment, the fecal samples of mice were collected aseptically at days 0, 7, and 14, and real-time fluorescent quantitative PCR（FQ-PCR） was carried out for the quantitative determination of exogenous probiotics. The results showed that probiotics not only mitigated diarrhea in mice and promoted mouse growth, but also exhibited a significant effect on the restoration of intestinal flora in mice with diarrhea. The results from FQ-PCR analysis indicated that the exogenous probiotics Lactobacillus acidophilus NCFM, Bifidobacterium lactis Bi-07, and Lactobacillus rhamnosus HN001 were able to colonize and survive after the administration of probiotics was stopped, but showed a certain downward trend over time.