Effect and Mechanism of Steamed Allii Sativi Bulbus Polysaccharide Against Dysbiosis-induced Diarrhea in Young Rats / 中国实验方剂学杂志

ABSTRACT

ObjectiveTo verify the efficacy of steamed Allii Sativi Bulbus polysaccharide in regulating the intestinal flora of young dysbiosis-induced diarrhea rats based on 16S rRNA gene sequencing. MethodThe young SD rats were randomly divided into blank group，model group，positive drug group （bifid triple viable capsules），and high-dose and low-dose steamed Allii Sativi Bulbus polysaccharide groups，six in each group. The dysbiosis-induced diarrhea rat model was established，and the blank group and the model group were given normal saline by gavage （each 10 mL·kg-1），and the high-dose and low-dose steamed Allii Sativi Bulbus polysaccharide groups were administered with corresponding drugs （500 mg·kg-1 and 250 mg·kg-1， respectively） ，once a day for seven consecutive days. The loose stool rate，loose stool grade，diarrhea index，small intestine propulsion rate and hematoxylin-eosin （HE） staining were used as indexes to investigate the effect of steamed Allii Sativi Bulbus polysaccharide on improving diarrhea symptoms in young rats. The feces of rats were collected for 16S rRNA gene high-throughput sequencing. ResultCompared with the model group， the positive drug group and the high-dose and low-dose steamed Allii Sativi Bulbus polysaccharide groups had alleviated symptoms， down-regulated loose stool rate and diarrhea index （P<0.01） and decreased small intestine advancement rate （P<0.05）. HE staining showed that after the treatment with steamed Allii Sativi Bulbus polysaccharide，the inflammatory cell infiltration of the colon tissue was improved and the intestinal gland recovered to the normal condition，which indicated that steamed Allii Sativi Bulbus polysaccharide could significantly ameliorate the diarrhea in young rats. The sequencing results revealed that steamed Allii Sativi Bulbus polysaccharide had a moderating effect on the abundance of the intestinal flora of young dysbiosis-induced diarrhea rats，elevating the flora richness and diversity indexes. Specifically， the abundance of Bacteroidota was increased while that of Firmicutes and Proteobacteria was decreased. ConclusionSteamed Allii Sativi Bulbus polysaccharide can be used to treat dysbiosis-induced diarrhea in young rats by regulating the abundance of intestinal microbiota.