Objective

2

To explore the therapeutic effect and possible mechanism of Banxia Xiexintang and its disassembled prescriptions in regulating the flora disorder induced by mixed antibiotics in young rats.

Method

2

Seventy male BALB/C young rats were randomly assigned into 7 groups： blank group， model group， Bifidobacterium tetralogy viable tablets （0.68 g·kg

-1

） group， Banxia Xiexintang （9.1 g·kg

-1

） group， Xinkai （3.19 g·kg

-1

） group， Kujiang （1.82 g·kg

-1

） group， and Ganbu （4.1 g·kg

-1

） group， with 10 rats in each group. Except the blank group， the other groups were given mixed antibiotics by gavage to induce intestinal flora disorder. After 14 days， the rats in different drug groups were administrated with corresponding drugs by gavage， and those in the blank group and model group with the same amount of normal saline once a day for 14 days. After that， fecal samples were collected aseptically for 16S rDNA sequencing of intestinal flora， and lipopolysaccharide （LPS， 10 mg·kg

-1

） was injected intraperitoneally to induce inflammatory reaction. The tissue morphology of colonic mucosa was observed via hematoxylin-eosin （HE） staining， and the macrophage infiltration of colonic mucosa was observed via toluidine blue staining and immunohistochemistry. The expression of interleukin-1

β

（IL-1

β

）， interleukin-6 （IL-6）， interleukin-8 （IL-8）， tumor necrosis factor-

α

（TNF-

α

）， and interleukin-10 （IL-10） mRNA were determined by real-time fluorescence quantitative polymerase chain reaction （Real-time PCR）.

Result

2

Compared with the blank group， the modeling changed the intestinal flora structure of the young rats （

P

<

0.01）， damaged the colonic mucosa， reduced the macrophage infiltration， and down-regulated the mRNA levels of IL-1

β

， IL-6， IL-8， TNF-

α

， and IL-10 （

P

<

0.01）. Compared with the model group， bifidobacterium quadruple viable tablets， Banxia Xiexintang and its disassembled prescriptions increased the diversity of intestinal flora and the relative abundance of beneficial bacteria such as Bacteroidetes and Firmicutes （

P

<

0.01）. At the same time， they ameliorated colonic mucosal injury （

P

<

0.05，

P

<

0.01）， increased macrophage infiltration （

P

<

0.05，

P

<

0.01）， and up-regulated the mRNA levels of IL-6， IL-8， and TNF-

α

（

P

<

0.01）. The mRNA level of IL-1

β

was up-regulated in Bifidobacterium tetralogy viable tablets， Banxia Xiexintang， Kujiang， and Ganbu groups （

P

<

0.01）， and that of IL-10 was up-regulated in Bifidobacterium tetralogy viable tablets， Banxia Xiexintang， Xinkai， and Ganbu groups （

P

<

0.01）.

Conclusion

2

Banxia Xiexintang and the disassembled prescriptions can adjust the intestinal flora of young rats exposed to antibiotics and protect the immune barrier of colonic mucosa after intestinal flora disorder. In particularly， the whole prescription of Banxia Xiexintang demonstrates the best performance.