# L‐Theanine Mitigates Aβ1‐42‐Induced Apoptosis in SH‐SY5Y Cells

## TL;DR

L-theanine, a compound found in tea, may protect nerve cells from damage linked to Alzheimer's disease by reducing cell death and oxidative stress.

## Contribution

This study demonstrates L-theanine's potential to mitigate Aβ1-42-induced apoptosis in SH-SY5Y cells through mechanisms like oxidative stress suppression.

## Key findings

- L-theanine significantly inhibits Aβ1-42-induced apoptosis in SH-SY5Y nerve cells.
- The compound suppresses mitochondrial membrane damage and oxidative stress.
- L-theanine reduces extracellular nitrite accumulation in affected cells.

## Abstract

Alzheimer's disease (AD) is a neurodegenerative disorder that significantly impacts the physical and mental health of elderly individuals. Previous research has demonstrated a close association between neurodegenerative diseases and neuronal apoptosis, with cognitive disorders such as AD often exhibiting pathological features, including neuronal apoptosis. In recent years, the application of natural plant molecules for the prevention of AD has emerged as a focal point in food nutrition research. L‐theanine, a unique active compound found in tea, has been shown to possess neuroprotective properties, although its underlying mechanisms remain to be fully elucidated. This study established an in vitro model of AD using SH‐SY5Y cells induced by Amyloid‐beta (1‐42) (Aβ1‐42) to investigate whether L‐theanine can interfere with Aβ1‐42‐induced apoptosis in these cells and to explore its potential mechanisms of action, thereby providing a theoretical foundation for the intervention and prevention of AD. L‐theanine effectively inhibits Aβ1‐42‐induced apoptosis in SH‐SY5Y cells, potentially through the suppression of oxidative stress and preservation of mitochondrial function.

Our research findings indicate that L‐theanine significantly inhibits Aβ1‐42 induced apoptosis in SH‐SY5Y nerve cells, potentially through mechanisms involving the suppression of mitochondrial membrane damage, oxidative stress and the accumulation of extracellular nitrite. These results suggest that L‐theanine is a potential natural substance for intervention in Alzheimer's disease.