Iridoids in gardenia fruit: key components in liver disease therapy

Liver diseases pose a serious threat to human health, necessitating the development of safe and effective preventive and therapeutic strategies. Gardenia fruit (GF), the mature fruit of Gardenia jasminoides Ellis, has been widely used in both food and medicinal applications. Over time, GF and its major bioactive constituents, the iridoids, have demonstrated significant potential in the prevention and treatment of various liver diseases. This review first summarizes the structural characteristics and pharmacological activities of the major iridoids in GF from a phytochemical perspective. It then focuses on the therapeutic effects of GF extracts against non-alcoholic fatty liver disease, cholestatic liver disease, acute liver injury, and liver fibrosis. Furthermore, the review provides a comprehensive examination of the multi-target mechanisms by which iridoids mediate their hepatoprotective effects. These mechanisms include the regulation of lipid metabolism, attenuation of cholestasis, suppression of inflammation and oxidative stress, amelioration of mitochondrial dysfunction, modulation of autophagy, as well as anti-fibrotic, anti-hepatocarcinogenic, and detoxification activities. Among these, the inhibition of inflammation and oxidative stress is highlighted as a primary mechanism of action. In addition, this review critically evaluates the current limitations associated with the use of GF and its iridoids in liver disease treatment and discusses potential directions for future research. The aim of this review is to provide theoretical foundations and scientific guidance for the further research and development of GF-based therapeutic agents.