Abstract:
Objective
By observing the changes of bile acid metabolites in serum of RSV-infected rats, we observed indirectly the changes of intestinal flora caused by RSV. Based on the "Lung-Intestine Theory", the regulation mechanism of Dingchuan decoction on bile acid metabolism and intestinal microflora after RSV infection was further elucidated.
Methods
Wistar rats were randomly divided into normal control group, RSV infection model group and Dingchuan decoction group. Except the normal control group, the other groups were intranasally inoculated with RSV Long strain virus solution. The general state and pathological changes of each group of rats were evaluated, and the related metabolites were detected by liquid chromatography-mass spectrometry(LC-MS).
Results
(1)Dingchuan decoction could regulate the general state of rats after RSV infection, reduce the lung index after RSV infection and improve pathological changes. (2)Compared with normal group, the levels of serum CA(citrate), TCA(taurocholic acid), TUDCA(tauroursodeoxycholic acid), CDCA(chenodeoxycholic acid), 7-ketodeoxycholic acid and phenylacetic acid in RSVinfected rats were significantly increased, while GCDCA(glycine chenodeoxycholic acid) was significantly decreased, and the difference was statistically significant（P＜0.05）；compared with the RSV model group, the serum levels of CA(citric acid), TCA(taurocholic acid), TUDCA(tauroursodeoxycholic acid), CDCA(chenodeoxycholic acid), GCDCA(glycine chenodeoxycholic acid), 7-ketodeoxycholic acid and phenylacetic acid of Dingchun decoction group were all downregulated, the difference being statistically significant.
ConclusionDingchuan decoction can effectively regulate the imbalance of bile acid metabolism in serum of rats after RSV infection, and thus maintain the stability of intestinal microflora.

Key words: Respiratory syncytial virus, Lung-intestine Theory, Dingchuan decoction, Bile acid metabolism, Intestinal flora, Rat