Traditional Paeonia radix alba formulas and their bioactive metabolites: a narrative review focusing on hepatoprotection in chronic liver diseases

Aim of the Review Paeoniae radix alba (PRA), a traditional Chinese medicine used for centuries to “soothe the liver” and relieve pain, has attracted increasing attention for its potential role in liver diseases. Emerging pharmacological evidence indicates that PRA exerts hepatoprotective, anti-inflammatory, antioxidant, and immunomodulatory effects. This paper reviews traditional Chinese medicine prescriptions containing PRA, its main active metabolites, and their underlying mechanisms in the treatment of liver diseases, and preliminarily summarizes its hepatotoxicity-attenuating mechanisms, to provide directions for further multifaceted research. Materials and Methods We searched Web of Science using the following strategies: AB=(xiaoyaosan OR XYS) AND AB = liver, with analogous searches for the other formulas; AB=(paeoniflorin OR PF OR PAE) AND AB=(“Paeonia lactiflora Pall” OR “Paeoniae radix alba” OR PRA) AND AB = liver, with analogous searches for the other metabolites; AB = process* AND AB=(“Paeonia lactiflora Pall” OR “Paeoniae radix alba” OR PRA) AND AB = liver; and AB=(hepatotoxicity OR detoxification) AND AB=(“Paeonia lactiflora Pall” OR “Paeoniae radix alba” OR PRA). We prioritized studies published within the past 5 years and those with more complete methodological details. Results PRA and its classic prescriptions, including Xiaoyao San, Shaoyao Gancao Tang, Danggui Shaoyao San and Sini San, have made significant contributions to the treatment of liver diseases. Notably, despite limited current research, PRA can effectively attenuate the hepatotoxicity of other botanical drugs, which is closely associated with its multiple protective effects against liver injury. Therefore, rational and cautious combination therapy should be considered in the clinical application of PRA to maximize its unique advantages and minimize potential risks. Conclusion Within the framework of TCM theory, PRA and its metabolites appear promising for the management of liver diseases and may also mitigate hepatotoxicity associated with certain herbal medicines. Further mechanistic investigations and clinical studies are needed to validate these findings.