Herba Sideritis: A putative adaptogen for reducing the risk of age-related cognitive decline and neurodegenerative disorders

Traditional use of Greek mountain tea (GMT), Herba Sideritis (Sideritis scardica Griseb.), is used to treat the common cold and mild gastrointestinal disorders. Recent studies suggest its potential efficacy for reducing the risk of age-related cognitive decline and neurodegenerative diseases, which could be associated with the common mechanisms of action. The aims of this monograph were: (i) to elaborate a rationale for a mode of pharmacological action, which is likely associated with a regulation of the neuroendocrine-immune complex (stress system), and (ii) to systematically update new evidence of the quality, efficacy, and safety of GMT preparations and validate their potential health benefits. Literature screening using the Pubmed database and original publications were assessed according to WHO criteria for monographs of herbal medicines. Results. Sideritis scardica extracts and its ingredient phenylethyl-phenylpropanoid glycoside acteoside (AC, syn. verbascoside) exhibited cognitive improvement, stress-protective, neuroprotective, neurogenesis, anxiolytic, anti-aging, anti-inflammatory, antimicrobial, gastroprotective, glycemic, anti-obesity, antioxidant, and anti-tumor activity. The recent findings supported by preclinical and clinical data suggest using Herba Sideritis extracts to improve cognitive functions and mental disorders in aging. This monograph, for the first time, provided systematic information on the safety, efficacy, and quality of Herba Sideritis to facilitate its use in WHO Member States for reducing the risk of age-related cognitive decline and neurodegenerative disorders. Further research of preclinical and clinical studies is needed to thoroughly validate the potential health benefits of GMT and clarify the mechanisms underlying of adaptogenic of GMT.