Multi-omics reveals deoxycholic acid modulates bile acid metabolism via the gut microbiota to antagonize carbon tetrachloride-induced chronic liver injury.

Deoxycholic acid (DCA) serves essential functions in both physiological and pathological liver processes; nevertheless, the relationship among DCA, gut microbiota, and metabolism in chronic liver injury remain insufficiently understood. The primary objective of this study is to elucidate the potential of DCA in ameliorating chronic liver injury and evaluate its regulatory effect on gut microbiota and metabolism via a comprehensive multi-omics approach. Our study found that DCA supplementation caused significant changes in the composition of gut microbiota, which were essential for its antagonistic effect against CCl4-induced chronic liver injury. When gut microbiota was depleted with antibiotics, the observed protective efficacy of DCA against chronic liver injury became noticeably attenuated. Mechanistically, we discovered that DCA regulates the metabolism of bile acids (BAs), including 3-epi DCA, Apo-CA, and its isomers 12-KLCA and 7-KLCA, IHDCA, and DCA, by promoting the growth of A.muciniphila in gut microbiota. This might lead to the inhibition of the IL-17 and TNF inflammatory signaling pathway, thereby effectively countering CCl4-induced chronic liver injury. This study illustrates that the enrichment of A. muciniphila in the gut microbiota, mediated by DCA, enhances the production of secondary bile acids, thereby mitigating chronic liver injury induced by CCl4. The underlying mechanism may involve the inhibition of hepatic IL-17 and TNF signaling pathways. These findings propose a promising approach to alleviate chronic liver injury by modulating both the gut microbiota and bile acids metabolism.

A population-based study on prevalence and predisposing risk factors of infant functional gastrointestinal disorders in a single center in Southern Fujian.

Background and aim: The prevalence of infant functional gastrointestinal disorders (FGIDs) varies across different areas but is largely unknown in southern Fujian. The aim of this study is to evaluate the prevalence of infant FGIDs in southern Fujian according to Rome IV diagnostic criteria. Methods: A cross-sectional prospective questionnaire-based survey was conducted among healthy infants between 0 and 3 months of age in southern Fujian. A total of 1,006 infants who received a physical examination from October 2017 to October 2018 were recruited in this study. Parents or caregivers provided demographic information and completed the questionnaire on gastrointestinal symptoms for infants. Infants with FGIDs were diagnosed using the Rome IV criteria. Results: Based on the Rome IV criteria, the prevalence of having a FGID in infants is 58.3% (586/1,006). The most common FGIDs in infants were regurgitation (45.7%, 460/1,006), followed by difficult defecation (3.6%, 36/1,006), functional constipation (3.2%, 32/1,006), and colic (2.4%, 24/1,006). No infants fulfilled diagnostic criteria for rumination syndrome and cyclic vomiting syndrome. Among the infants with FGIDs, 457 cases (78.0%, 457/586) were found with single FGID. Combined FGIDs were diagnosed in 129 (22.0%, 129/586) infants; of whom, 21.2% (124/586) had double disorders and 0.9% (5/586) had triple disorders. The most common combined FGIDs were regurgitation and difficult defecation (12.8%), followed by regurgitation and colic (2.4%). Risk factor analysis revealed that younger paternal age (B = 0.424, P = 0.004), paternal history of FGIDs (B = 0.821, P = 0.000), maternal history of FGIDs (B = 0.427, P = 0.012), and probiotics received in infant (B = 0.324, P = 0.032) were associated with an increased risk of infant FGIDs, whereas vitamin D supplementation after birth (B = -0.690, P = 0.000) can reduce the risk of developing FGIDs. Conclusion: FGIDs are common in infants living in southern Fujian according to Rome IV diagnostic criteria. The most common FGIDs in infants were regurgitation, difficult defecation, and functional constipation. Factors including younger paternal age, parental history of FGIDs, and the probiotic supplementation in infant showed a significant association with infant FGIDs. Whereas, vitamin D supplementation in infant was found to be a protective factor against FGIDs.