In a remarkable scientific discovery, graphene oxide has been found to reduce the toxicity of Alzheimer’s causing proteins. This is based on the probable early driver of Alzheimer’s disease being linked to the accumulation of molecules called amyloid peptides.
Amyloid peptides cause cell death and are commonly found in the brains of Alzheimer’s patients. Specifically, misfolded amyloid-beta peptides, Aβ peptides, that accumulate and aggregate in the brain, are believed to be the underlying cause of Alzheimer’s disease. They trigger a series of harmful processes in the neurons (brain cells) – causing the loss of many vital cell functions or cell death, and thus a loss of brain function in the affected area.
It is thought the amyloid aggregates exert their neurotoxic effects by causing various cellular metabolic disorders, such as stress in the endoplasmic reticulum – a major part of the cell, in which many of its proteins are produced. This reduces a cell’s ability to handle misfolded proteins, and consequently increase the accumulation of these proteins. The aggregates also affect the function of the mitochondria, the cells’ powerhouses.
Consequently, the neurons are exposed to increased oxidative stress (reactive molecules called oxygen radicals, which damage other molecules). Brain cells are particularly sensitive. Essentially the impacted cells age faster than normal, show endoplasmic reticulum stress and mitochondrial dysfunction.
The new study indicates that treatment with graphene oxide leads to reduced levels of aggregated amyloid peptides. This has been demonstrated in a yeast cell model (Saccharomyces cerevisiae). With this, scientists at Chalmers University of Technology, Sweden have shown that yeast cells that accumulate these misfolded amyloid peptides can recover after being treated with graphene oxide nanoflakes.
This supports other studies that show success using graphene oxide, although this had not previously been demonstrated in a biological model. Graphene oxide nanoflakes are two-dimensional carbon nanomaterials with special properties, including outstanding conductivity and high biocompatibility.
In terms of what is happening, graphene oxide affects the metabolism of the cells, in a way that increases their resistance to misfolded proteins and oxidative stress. The nanoflakes are hydrophilic (water soluble) and interact well with biomolecules such as proteins. When graphene oxide enters living cells, it is able to interfere with the self-assembly processes of proteins.
In one cellular pathway, graphene oxide acts directly to prevent amyloid-beta42 accumulation.
The results have been repeated using a laboratory model for human cells, with similar findings. This suggests graphene oxide holds great potential for future research in the field of neurodegenerative diseases.
The research appears in the journal Advanced Functional Materials, titled “Graphene Oxide Attenuates Toxicity of Amyloid-β Aggregates in Yeast by Promoting Disassembly and Boosting Cellular Stress Response.”
