Andrographolide: a promising therapeutic agent against organ fibrosis

Fibrosis is the terminal pathology of chronic illness in many organs, marked by excessive accumulation of extracellular matrix proteins. These changes influence organ function, ultimately resulting in organ failure. Although significant progress has been achieved in comprehending the molecular pathways responsible for fibrosis in the last decades, effective and approved clinical therapies for the condition are still lacking. Andrographolide is a diterpenoid isolated and purified mainly from the aboveground parts of the Andrographis paniculata plant, which possesses good effects of purging heat, detoxifying, antibacterial and anti-inflammatory. In-depth research has gradually confirmed the anticancer, antioxidant, antiviral and other effects of Andro so that it can play a preventive and therapeutic role in various diseases. Over the past few years, an increasing number of research findings have indicated that Andro exerts antifibrotic effects in various organs by acting on transforming growth factor-β/small mother against decapentaplegic protein, mitogen-activated protein kinases, nuclear factor-E2-related factor 2, nuclear factor kappa-B and other signalling molecules to inhibit inflammation, oxidative stress, epithelial-mesenchymal transition, fibroblast activation and collagen buildup. This review presents a compilation of findings regarding the antifibrotic impact of Andro in tissue and cell models in vitro and in vivo. Emphasis is placed on the potential therapeutic benefits of Andro in diseases related to organ fibrosis. Existing studies and cutting-edge technologies on Andro pharmacokinetics, toxicity and bioavailability are briefly discussed to provide evidence for accelerating its clinical conversion and adoption.