Green Tea Extracts Attenuate Brain Dysfunction in High-Fat-Diet-Fed SAMP8 Mice

Area of Science:

• Neuroscience
• Nutritional Science
• Gerontology

Background:

• Unhealthy diets accelerate metabolic disorders and cognitive decline during aging.
• Green tea extracts (GTEs) exhibit metabolic and neuroprotective benefits, but their impact on aging-related brain dysfunction from poor diets is not fully understood.
• Senescence-accelerated mouse prone-8 (SAMP8) mice serve as a model for studying aging and age-related diseases.

Purpose of the Study:

• To investigate the neuroprotective effects of GTEs in SAMP8 mice fed a high-fat (HF) diet.
• To determine if GTEs can mitigate HF diet-induced cognitive impairment and brain dysfunction in aging mice.

Main Methods:

• SAMP8 mice were assigned to three groups: control diet, HF diet, or HF diet supplemented with 0.5% GTEs (HFGT) for four months.
• Cognitive function was assessed by memory retention tests.
• Brain tissue analysis included measuring amyloid-beta (Aβ₁₋₄₂), malondialdehyde (MDA) levels, and the expression of synaptic plasticity proteins like brain-derived neurotrophic factor (BDNF) and postsynaptic density protein 95 (PSD95).

Main Results:

• HF diet consumption led to reduced memory retention and increased Aβ₁₋₄₂ accumulation in SAMP8 mice.
• HF diet-fed mice showed elevated lipid oxidative stress (increased MDA levels) and reduced levels of synaptic plasticity proteins (BDNF, PSD95).
• GTE supplementation in the HFGT group attenuated these negative effects, preserving memory function and synaptic integrity.

Conclusions:

• GTEs may counteract high-fat diet-induced brain dysfunction in aging mice (SAMP8 model).
• The neuroprotective mechanisms of GTEs involve preserving synaptic plasticity and exerting anti-oxidative effects.
• GTEs show potential for ameliorating diet-induced cognitive aging and brain dysfunction.