To explore the mechanism of Suanzaoren Decoction in the treatment of insomnia from endogenous bile acid regulation, the present study investigated the hepatoprotective effect of Suanzaoren Decoction and the molecular changes of bile acids in the serum, liver, and ileum of insomnia model mice and Suanzaoren Decoction treated mice. The insomnia model in mice was established by the sleep deprivation method. After Suanzaoren Decoction(48.96 mg·kg~(-1)·d~(-1)) intervention by gavage for 7 days, the related indicators, such as water consumption, food intake, body weight, aspartate aminotransferase(AST), alanine transaminase(ALT), and total bile acid(TBA) were detected, and the pathological changes of the liver and ileum were observed. The molecular levels and distribution of 23 bile acids in the serum, liver, and ileum were analyzed by UPLC-MS/MS combined with principal component analysis(PCA) and partial least squares discriminant analysis(PLS-DA). The results showed that Suanzaoren Decoction could improve the decreased water consumption and food intake, weight loss, and increased AST and ALT in the model group, and effectively reverse the injury and inflammation in the liver and ileum. The bile acids in the liver of the insomnia model mice were in the stage of decompensation, and the bile acids in the serum, liver, and ileum of the mice decreased or increased. Suanzaoren Decoction could regulate the anomaly of some bile acids back to normal. Seven bile acids including glycoursodeoxycholic acid(GUDCA), glycodesoxycholic acid(GDCA), tauro-α-MCA(T-α-MCA), α-MCA, taurodeoxycholate(TDCA), T-β-MCA, and LCA were screened out as the main discriminant components by PLS-DA. It is concluded that Suanzaoren Decoction possesses the hepatoprotective effect and bile acids could serve as the biochemical indicators to evaluate the drug efficacy in the treatment of abnormal liver functions caused by insomnia. The mechanism of Suanzao-ren Decoction in soothing the liver, resolving depression, tranquilizing the mind, and improving sleep may be related to the molecular regulation of bile acid signals.
Keywords: Suanzaoren Decoction; bile acid; ileum; insomnia; liver; serum.