Effect of Shaoyao Gancao Granules on Intestinal Flora in Mice with Alopecia Areata and Syndrome of Liver Depression and Spleen Deficiency:A Study Based on 16S rDNA Technique
Objective To investigate the mechanism of action of Shaoyao Gancao Granules in promoting hair regenerationin mice with alopecia areata (AA)and syndrome of liver depression and spleen deficiency based on 16S rDNA technique from the perspective of intestinal flora.Methods C57BL/6J mice were randomly divided into blank group,model group,positive con-trol drug group,and high-,middle-,and low-dose Shaoyao Gancao Granules groups.All mice except those in the blank group were treated with chronic unpredictable mild stress combined with 5% imiquimod cream for 21 days to establish a mouse model of AA with syndrome of liver depression and spleen deficiency.Drug intervention was initiated on day 8 of the experiment as follows:the mice in the blank group and the model group were given normal saline,those in the high-,middle-,and low-dose Shaoyao Gancao Granules groups were given Shaoyao Gancao Granules at a dose of 7.8、3.9、1.95 g/kg,respectively,and those in the positive control drug group were given compound glycyrrhizin tablets 20 mg/kg,by gavage for 14 consecutive days.Af-ter the experiment ended,immunohistochemistry was used to measure the expression levels of CD4+and CD8+T cells in skin lesion of the mice in the blank group and the model group;dermoscopy was used to observe the features of hair in the area of skin lesion;the tail suspension test (TST)and the forced swimming test (FST)were used for behavioral assessment;the 16S rDNA technique was used to measure the changes in intestinal flora,and PICRUSt2 was used to predict the function of intesti-nal flora;a correlation analysis was performed for differentially expressed flora and behavioral assessments.Results For the mice in the model group,dermoscopic findings of skin lesion,immunohistochemistry,and behavioral assessments showed that Shaoyao Gancao Granules effectively promoted hair regeneration and improved macroscopic representation and behavioral mani-festation.Compared with the blank group,the model group had a significant reduction in the relative abundance of Firmicutes and a significant increase in the relative abundance of Bacteroidetes (P<0.05),as well as a significant reduction in Lactobacil-lus (P<0.05)and significant increases in StaPhylococcus,Duncaniella,and Paramuribaculum (P<0.05).Shaoyao Gancao Granules at different doses could significantly reverse the increases or reductions in the above differentially expressed flora,in-volving various metabolic pathways such as glycoprotein biosynthesis and metabolism and the metabolism of cofactors and vita-mins.FST was negatively correlated with the relative abundance of Firmicutes and was positively correlated with Paramuribac-ulum.Conclusion For AA mice with syndrome of liver depression and spleen deficiency,Shaoyao Gancao Granules can effec-tively promote hair regeneration and alleviate the symptoms of liver depression and spleen deficiency,possibly by regulating the composition of intestinal flora and promote the balance of flora.