Association of Tea Consumption with Risk of Alzheimer’s Disease and Anti-Beta-Amyloid Effects of Tea

Abstract

Neurodegenerative disease Alzheimer’s disease (AD) is attracting growing concern because of an increasing patient population among the elderly. Tea consumption is considered a natural complementary therapy for neurodegenerative diseases. In this paper, epidemiological studies on the association between tea consumption and the reduced risk of AD are reviewed and the anti-amyloid effects of related bioactivities in tea are summarized. Future challenges regarding the role of tea in preventing AD are also discussed.

Regardless of the Brewing Conditions, Various Types of Tea are a Source of Acetylcholinesterase Inhibitors

“…Studies conducted worldwide confirm the existence of a correlation between drinking tea and positive effects on human cognitive function [14,17,36]. In their literature review, Polito et al [14] analyzed epidemiological data and concluded that drinking tea can reduce the risk of AD and other neurodegenerative diseases, as well as improve cognitive functions in the elderly.…”

“…Studies conducted worldwide confirm the existence of a correlation between drinking tea and positive effects on human cognitive function [14,17,36]. In their literature review, Polito et al [14] analyzed epidemiological data and concluded that drinking tea can reduce the risk of AD and other neurodegenerative diseases, as well as improve cognitive functions in the elderly. Okello et al [37] demonstrated that green and black tea extracts can improve the efficiency of the cholinergic system, which may substantially contribute to alleviating the effects of the cholinergic deficit observed in AD and other age-related memory disorders.…”

“…Due to antioxidant activity, it is currently believed that drinks rich in polyphenols are recommendable as ingredients of a natural supplementary therapy, helping to alleviate the symptoms of AD [13]. One of those drinks is tea, including fruit tea variants which have been gaining considerable popularity in recent years due to their attractive aroma, taste, and the health benefits of constituting a natural source of antioxidants [14][15][16]. The ingredients of such tea-fruit, flowers, leaves, and other plant material-are an important source of phenolic compounds, as well as vitamins and minerals.…”

“…They function by inhibiting the amyloid precursor protein (APP) splitting, preventing incorrect protein folding and membrane damage induced by Aβ. They also suppress Aβ oligomer aggregation, alleviate Aβ-induced oxidative stress, regulate the signal pathway including Aβ aggregation, inhibit microtubule associated protein (TAU) hyperphosphorylation, and inhibit AChE [14,30,31]. The caffeine contained in tea has also been shown to have protective properties against neurological diseases such as AD due to its stimulatory effects on the central nervous system [32].…”

Biomimetic Nanocarrier Targeting Drug(s) to Upstream-Receptor Mechanisms in Dementia: Focusing on Linking Pathogenic Cascades

“…The authors concluded that their findings demonstrate that only Aβ(1-42) contains unique structural features that facilitate membrane insertion and channel formation, now aligning ion channel formation with the neurotoxic effect of Aβ(1-42) compared to Aβ in Alzheimer's disease [53]. (In addition, tea polyphenols have been repeatedly reported (e.g., [54]) to protect cells from Aβ-mediated neurotoxicity, by dose-dependently inhibiting the formation of Aβ aggregates (e.g., from fresh Aβ(1-42) peptides), through the destabilization of preformed Aβ aggregates. These green tea polyphenols (regularly ingested worldwide via tea beverage consumption) are considered to be valuable, for the prevention and therapeutic treatment of Alzheimer's disease, via the combined effect of inhibiting Aβ aggregate formation and protecting neurons from the toxicity (e.g., oxidative stress) induced by Aβ [54].…”