Lamiaceae: A source of nootropics with utility in neurodegenerative diseases
Nootropics are ingestible products that are presumed to improve mental functions such as cognition, memory, intelligence, motivation, attention, and concentration; and, are thought to work by altering the availability of the supply of neurochemicals (neurotransmitters, enzymes and hormones) to the brain by improving the brain’s oxygen supply, or by stimulating nerve growth. The occurrence of plants with nootropic properties has been known since antiquity, and Ginko biloba, Celastrus paniculatus, Salvia officinalis, Rosmarinus officinalis and Galanthus caucasicus, among others, have been used for a memory enhancement benefit (Dastmalchi et al, 2007). However, the compounds of some nootropic plants, or their modes of action that results in improved brain function, has remained uninvestigated. The aim of this project is the investigation of suspected nootropic plants in anecdotal medicinal accounts to establish possible cholinergic activity and the chemistry associated with it, expecting to find novel compounds useful in the development of improved therapies for Alzheimer’s disease (AD). Examination of these accounts led us to select a group of plants for study that include Salvia verticillata, Melissa officinalis, and Angelica sinensis. We have established in the laboratory an in vitro bioautographic technique to measure Acetylcholinesterase inhibitory (AChEi) activity associated with the compounds of the plants chosen for this investigation. This exploratory study yielded activity in all three species with the highest associated with M. officinalis. We chose to further study the activity of M. officinalis and have proceeded with the chemical analysis of the active extract using TLC and diagnostic reagents, which suggest the phenolic nature of the most active chemical component. This procedure was followed by HPLC analysis, the chromatographic fractionation of the crude extracts, UV-VIS spectrophotometry, and ESIMS mass spectrometry. A major AChEi principle has been isolated from M. officinalis and its structure has been elucidated to be rosmarinic acid, an ester of caffeic acid, and a 3,4-dihydroxyphenyllactic acid (Avila et al, 2004). Furthermore, it is argued that a contributing factor to the pathology of Alzheimer’s disease is oxidative stress (Perry et al, 2002). Thus, neuronal protection from reactive oxygen species (ROS) is advantageous. We have therefore measured the antioxidant activity of members of the Lamiaceae plant family.
Biological sciences honors program; Alzheimer's Disease; Natural remedies; medicinal chemistry; neurodegenerative disorders; plant biology
B.A. of Biological Sciences
Bachelor of Arts
dissertation or thesis