Cholestatic liver disease (CLD) is a pathological condition characterized by impaired bile formation, secretion, and excretion. However, the key pathophysiological mechanisms of CLD remain elusive, and therapeutic efficacy is unsatisfactory. We administered berberine (BBR) or dihydroberberine (dhBBR) in bile duct ligation-, ANIT-, and mdr2-/- CLD mouse models to evaluate the anti-CLD effect. We conducted fecal microbiota transplantation to determine the role of gut microbiota in BBR's effect. We conducted a randomized, controlled clinical trial to evaluate the effects of BBR in patients with CLD. Oral BBR alleviates cholestatic liver injury in multiple mouse models. Gut microbes can transform BBR into dhBBR, which suppresses 5-HT production in gut enterochromaffin cells by antagonizing tryptophan hydroxylase 1 (TPH1) activity and downregulating Tph1 transcription. This further ameliorates CLD by interrupting the 5-HT/5HTR axis. A clinical study validated that BBR improved blood biochemical indicators in patients with CLD and decreased 5-HT levels. BBR is transformed by gut microbiota to ameliorate CLD via inhibiting 5-HT, suggesting potential novel strategies for further clinical use.
Tu et al. (2025) studied this question.