Molecular Targets of Tannic Acid in Alzheimer's Disease.
Tannic acid (TA) is a naturally occurring plant-derived polyphenol found in several herbaceous and woody plants, including legumes, sorghum, beans, bananas, persimmons, rasberries, wines and a broad selection of teas. Clinically, TA has strong antioxidant/free radical scavenging, antiinflammatory, anti-viral/bacterial, and anti-carcinogenic properties. While the aetiology of Alzheimer's disease (AD) remains unclear, this complex multifactorial neurodegenerative disorder remains the most common form of dementia, and is a growing public health concern worldwide. The neuroprotective effects of TA against AD have been shown in several in vitro and in vivo models of AD. Apart from its potent antioxidant and anti-inflammatory roles, evidence suggests that TA is also a natural inhibitor of β-secretase (BACE1) activity and protein expression. BACE1 is the primary enzyme responsible for the production and deposition of Aβ peptide. TA also destabilises neurotoxic amyloid beta (Aβ) fibrils in vitro. Apart from its effects on the Aβ cascade, TA can also inhibit the in vitro aggregation of tau peptide, a core component of intracellular neurofibrillary tangles (NFTs). This review summarizes the relevance of TA and TA-related vegetable extracts (tannins) in the pathogenesis of AD and its enzymatic targets. It also highlights the significance of TA as an important lead compound against AD.
Centre for Healthy Brain Ageing, School of Psychiatry, University of New South Wales, Sydney, Australia.
Nady
N
Braidy
School of Biotechnology and Biomolecular Sciences, University of New South Wales, Sydney, Australia.
Bat-Erdene
BE
Jugder
School of Medical Sciences, University of New South Wales, Sydney, Australia.
Anne
A
Poljak
Centre for Healthy Brain Ageing, School of Psychiatry, University of New South Wales, Sydney, Australia.
Tharusha
T
Jayasena
Applied Biotechnology Research Center, Baqiyatallah University of Medical Sciences, Tehran. Iran.
Seyed Mohammad
SM
Nabavi
Neuropsychiatric Institute, Prince of Wales Hospital, Sydney, Australia.
Perminder
P
Sachdev
Sydney Medical School, University of Sydney, Sydney, Australia.
Ross
R
Grant
D000544:Alzheimer Disease / Q000188:drug therapy* / Q000378:metabolism*; D053829:Amyloid Precursor Protein Secretases / Q000378:metabolism; D000818:Animals; D016282:Aspartic Acid Endopeptidases / Q000378:metabolism; D006801:Humans; D018696:Neuroprotective Agents / Q000737:chemistry / Q000627:therapeutic use*; D013634:Tannins / Q000737:chemistry / Q000627:therapeutic use*
D018696:Neuroprotective Agents; D013634:Tannins; D053829:Amyloid Precursor Protein Secretases; D016282:Aspartic Acid Endopeptidases; C509280:BACE1 protein, human
Alzheimer's disease; Aβ pathology; Tannic acid; neurons; tau; β-secretase