FAN: Green tea improves cognitive function in middle-aged and elderly Chinese by improving antioxidant stress

Mild cognitive impairment (MCI) is a condition between normal aging and dementia that is characterized by a mild decline in cognitive function but still maintaining full function
in daily life.
Many of the benefits of green tea have been reported
.
However, the effects of green tea on cognitive function remain controversial, and the mechanisms remain unclear
.
The objective of this study was to explore the relationship
between green tea consumption and cognitive function and related blood biomarkers in middle-aged and elderly Chinese and elderly people.

A total of 264 participants
aged 50-70 were recruited from Zhongnan Hospital of Wuhan University.
They were interviewed about green tea consumption patterns and underwent neuropsychological tests covering five main cognitive domains to assess cognitive ability, including the Montreal Cognitive Assessment (MoCA) and 10 other scales
.
Serum markers of oxidative stress were then measured, including superoxide dismutase (SOD), malondialdehyde (MDA), glutathione peroxidase (GPx), glutathione reductase (GR), and Alzheimer's disease (AD) markers, including β-amyloid (Aβ) 40, Aβ42, and phosphorylated tau-181 (pTau181).

The results showed that MoCA scores (P = 0.
000), Hopkins Speech Learning Test (HVLT) instant recall (P = 0.
012) and delayed recall (P = 0.
013) were significantly higher in the tea drinking group, while Trail Making Test-B (P = 0.
005) and Victoria Stroop test interference (P = 0.
000) were lower
。 In terms of markers of oxidative stress, the tea drinking group had lower serum MDA levels (P = 0.
002), higher serum SOD (P = 0.
005) and higher levels of GPx (P = 0.
007
).
In terms of AD markers, serum levels of pTau181 (P < 0.
000), Aβ42 (P = 0.
019) and total Aβ (P = 0.
034) were lower
in the tea drinking group, excluding serum Aβ40.
In logistic regression analysis, there was a clear negative correlation between green tea consumption and cognitive impairment (OR = 0.
26, 95% CI 0.
13-0.
52).

In summary, regular drinking of green tea is related to the cognitive function of middle-aged and elderly people, mainly in terms of
memory and executive function.
It may achieve a protective effect by reducing the pathological changes associated with AD and improving antioxidant capacity, and the greater the amount of tea citation, the stronger
the protective effect.

References:

Green tea improves cognitive function through reducing AD-pathology and improving anti-oxidative stress capacity in Chinese middle-aged and elderly people.