Shenqu xiaoshi oral solution enhances digestive function and stabilizes the gastrointestinal microbiota of juvenile rats with infantile anorexia

Massa Medicata Fermentata ("Shenqu") has long been applied in the treatment of indigestion in China; in fact, it is the active ingredient in the medicine Shenqu xiaoshi oral solution (SQXSOS). Based on robust clinical evidence, SQXSOS has shown efficacy in treating infantile anorexia (IFA).To investigate the underlying mechanisms by which SQXSOS treats IFA.The pharmacodynamic efficacy of SQXSOS was validated through a high-fat diet (HFD)-induced IFA model of juvenile rats, which share physiological similarities to two-year-old humans. Ultra-high-performance liquid chromatography coupled with time-of-flight mass spectrometry (UHPLC-TOF MS) was utilized to analyze the blood-dissolved components of SQXSOS in rats. After identification of the blood-dissolved components, the key components and target genes were predicted through network pharmacology analysis. To further validate the predicted key targets of the blood-dissolved components, RT-PCR and Western blotting were employed to measure the changes in their concentrations. Meanwhile, the efficacy of SQXSOS on the structure of gastrointestinal microbiota (GM) in IFA rats was investigated.SQXSOS, when administered to the IFA rats at a dosage equivalent to its clinical dose in humans (3.78 mL/kg/day), induced a significant increase in the gastric emptying rate (+1.9-fold) and small intestine advancement rate (+0.5-fold) compared to the IFA rats. Additionally, SQXSOS reversed the pathological changes observed in the serum levels of digestive functioning biochemicals (-32.4%～+250% compared to the model group, p < 0.05). A total of 40 blood-dissolved components were identified by UHPLC-TOF MS. Berberine, oleanolic acid, ganolucidic acid A, slicyluric acid, and glycyrrhetinic acid were identified as the key components of SQXSOS, while AKT1, STAT3, TP53, JUN, and MAPK1 were identified as the key targets enabling the therapeutic efficacy of SQXSOS in treating IFA. In a target validation study, the mRNA transcript levels of the abovementioned target genes were found to be significantly higher in the gastric antrum of IFA rats. However, SQXSOS administration (3.78 and 7.56 mL/kg/day) reduced the elevated mRNA transcript levels of the abovementioned target genes (41.1-77.3% compared to model group, p < 0.05). GM analysis revealed a significant increase in the Firmicutes/Bacteroidota ratio (F/B ratio, +214.2%) in the IFA fecal samples compared to normal rats, but the high dosage of SQXSOS induced a marked decrease in the F/B ratio (-44.1%) compared to IFA rats. Furthermore, the therapeutic efficacy of SQXSOS against IFA might be attributed to the increase in Muribaculaceae abundance and the decrease in Prevotellaceae_UCG_003 abundance.Mechanistic investigations indicated that the efficacy of SQXSOS in treating IFA could be manifested by regulating the transcription and expression levels of AKT1, MAPK1, STAT3, and TP53 genes in the gastric antrum as well as modulating the abundance of Muribaculaceae and Prevotellaceae_UCG_003 family. Furthermore, there are still some limitations: the contents of the key biochemicals remained to be determined, similar STAT3 transcription levels were observed in both normal rats and IFA rats, and it is crucial to further validate the potential target GM when transitioning from animal populations to humans.