Taxonomic Distribution of Medicinal Plants for Alzheimer's Disease: A Cue to Novel Drugs

Alzheimer's disease (AD) is a neurodegenerative disorder manifested by decline in memory and mild cognitive impairment leading to dementia. Despite global occurrence of AD, the severity and hence onset of dementia vary among different regions, which was correlated with the customary use of medicinal herbs and exposure level to the causatives. In spite of execution of versatile therapeutic strategies to combat AD and other neurodegenerative diseases, success is only limited to symptomatic treatment. The role of natural remedies remained primitive and irreplaceable in all ages. In some examples, the extracted drugs failed to show comparable results due to lack of micro ingredients. Micro ingredients impart a peerless value to natural remedies which are difficult to isolate and/or determine their precise role during treatment. A variety of plants have been used for memory enhancement and other dementia-related complications since ages. Acetyl choline esterase inhibition, antioxidant potential, neuroprotection, mitochondrial energy restoration, and/or precipitated protein clearance put a vast taxonomic variety into a single group of anti-AD plants. Secondary metabolites derived from these medicinal plants have the potential to treat AD and other brain diseases of common pathology. This review summarizes the potential of taxonomically diverse medicinal plants in the treatment of AD serving as a guide to further exploration.