Antioxidative Effects of Rhodiola Genus: Phytochemistry and Pharmacological Mechanisms against the Diseases

Rhodiola as one of traditional medicines has been used for clinical treatments due to its strong antioxidant properties. Phytochemical analysis revealed the presence of flavonoids, phenylpropanoids, phenylethanol/benzyl alcohol derivatives, cyanogenic glycosides and terpenoids. The bioactive compounds had been demonstrated to be effective at scavenging reactive oxygen species (ROS). The structures contain phenolic hydroxyl groups and unsaturated bonds. This article reviews antioxidant capacities of the extracts and bioactive components derived from Rhodiola plants. As the major pharmacological ingredient, salidroside is rigorously investigated and used in scientific researches and clinical practices. Accumulated evidences indicated that extracts of Rhodiola plants or salidroside could be able to reverse DNA damage and alter expression of cytokines and antioxidative enzymes induced by ROS. The underlying mechanisms for the antioxidative effects of the herb have been investigated in the last two decades. We summarize the possible effects and acting pathways for the herb involved in several chronic diseases in cardiovascular, respiratory, and nervous systems, as well as potential epigenetic influences. The information generated from experimental and clinical studies offered valuable insights for further investigations of medical potentials of Rhodiola plants.