Study On The Efficacy Mechanism Of Gegenqinlian Decoction On Diarrhea Caused By Intestinal Damp-heat Syndrome Based On Intestinal Flora-short-chain Fatty Acid

Objective:To investigate the effect of Gegenqinlian decoction on intestinal flora and short-chain fatty acid(SCFAs)in mice with diarrhea of intestinal dampness-heat syndrome,to clarify the correlation between intestinal flora and intestinal SCFAs levels in mice after diarrhea model of intestinal damp-heat syndrome and after Gegenqinlian decoction intervention,and to provide basis for the therapeutic mechanism of Gegenqinlian decoction on diarrhea of intestinal damp-heat syndrome.Methods:50 SPF male Kunming mice,among which 20 mice were normal group,30 mice were used to make diarrhea model of intestinal damp-heat syndrome.After the diarrhea model of intestinal damp-heat syndrome was established,10 mice were randomly selected from each group,the intestinal contents of mice in each group were extracted by aseptic manipulation.The remaining 10 mice in the normal group and 20 mice in the model group underwent the next stage,the 20 mice in the nodel group were randomly divided into self-healing group(n=10)and Gegenqinlian decoction intervention group(n=10),after the intervention of Gegenqinlian decoction,the contents of small intestine of mice in each group were extracted by aseptic operation.16S rRNA sequencing and gas chromatography-mass spectrometry(GC-MS)were used to detect the contents of mice,to analyze the changes of intestinal content flora and SCFAs content in mice with diarrhea of damp-heat syndrone and intervention of Gegenqinlian decoction.Results:(1)The structure of intestinal micro flora in the model group was changed,which showed that the relative abundance of Firmicutes decreased,while that of Bacteroidota,Proteobacteria and Actinobacteria increased.On the genus level,the abundance of beneficial bacteria Candidatus_Arthromitus,Lactobacillus and Limosilactobacillus in intestinal contents of mice in the model group decreased,while that of harmful bacteria Turicibacter increased(P>0.05).Lefse analysis showed that the relative abundance of Lactobacillus in the normal group was significantly higher than that in the model group,while the relative abundance of Actinobacteriota,Lachnospirales,Sporichthyaceae and Lachospiraceae in the model group was significantly higher than that in the normal group(P<0.05).(2)The abundance of acetic acid,butyric acid,valeric acid and caproic acid in the model group were decreased,but the abundance of propionic acid in the model group were increased(P>0.05).Spearman correlation analysis showed that valeric acid was positively correlated with while caproic acid was negatively correlated with Anaerobiospirillum(P<0.05).(3)The relative abundances of Firmicutes and Proteobacteria in the intestinal contents were decreased,while Bacteroidota were increased in the Gegenqinlian decoction group.At the genus level,the abundance of Ligilactobacillis and Candidatus_Arthromitus in the Gegenqinlian decoction group were higher than those in the self-healing group,but still lower than those in the normal group,the abundance of Lactobacillus increased and was higher than that of the normal group.The results of LEfSe analysis showed that Caulobacter and Ligilactabacillus were the biomarkers of intestinal content flora in normal mice,and Steptococcus was the characteristic bacterium in the Gegenqinlian decoction group.(4)The abundance of acetic acid,propionic acid,butyric acid,valeric acid and caproic acid in the intestinal contents of mice in the Gegenqinlian decoction group were decreased(P>0.05).Conclusion:The abundance and diversity of intestinal content flora increased,the relative abundance of Candidatus Arthromitus,Lactobacillus and Limosilactobacillis decreased,and the relative abundance of Twicibacter increased in mice of diarrhea with intestinal dampness-heat syndrome.diarrhea with intestinal dampness-heat syndrome reducc,d the abundance of acetic acid,butyric acid,valeric acid and caproic acid,but increased the abundance of propionic acid.Gegenqinlian decoction changed the abundance and diversity of intestinal flora in diarrhea mice with intestinal damp-heat syndrome,regulated the composition of intestinal flora,and decreased the relative abundance of Ligilactobacillus and Cardidatus Arthromitus in genus level,the relative abundance of Lactobacillus increased.Gegenqinlian decoction regulated the content of SCFAs in the intestinal contents of diarrhea mice with intestinal damp-heat syndrome.