Scientific Basis for Ayurvedic Medicinal Plants Against Alzheimer’s Disease

Abstract

Alzheimer’s disease (AD) is a degenerative brain disorder that manifests as a progressive deterioration of memory and mental function—a state of mind commonly referred to as “dementia” and causes changes in personality and behavior. AD was first described in 1906 by German neuropsychiatries Prof. Alois Alzheimer. Major pathological hallmarks of AD are characterized by deposition of abnormal amyloid β protein plaques, formation of neurofibrillary tangles of tau protein, and decline in cholinergic neurotransmission in brain. During the last decade, significant growth in Alzheimer’s prevalence has ignited the importance of more researches in the search of new medicine. One of the major clinical advances in the treatment of AD has been the use of acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) inhibitors to alleviate ACh level in brain although cholinergic compounds with nicotinic and muscarinic agonist properties also have attracted some interest. At present, there are very limited medications available to treat AD and most of the treatment is available only to delay the progression of symptoms and symptomatic relief for a short period of time. Medicinal plants represent a great deal of untapped reservoir of natural medicines and a potential source of natural AChE inhibitors. The structural diversity of their phytoconstituents makes them a valuable source of novel lead compounds for the quest of drugs to treat AD. Therefore, systematic ethnopharmacological screening of these plants may provide useful leads in the discovery of new drugs for AD therapy. With this background, a systematic review is prepared to bring forth an updated knowledge in various phytoextracts and their derivatives along with their possible action on cholinergic nervous system to ease AD therapy. Electronic database was used for searching the information related to studies performed in plants during last decades.