Green tea extract delivers molecular punch to disrupt formation of neurotoxic species

October 11, 2017, McMaster University
Credit: McMaster University

Green tea is widely considered to be beneficial for the brain. The antioxidant and detoxifying properties of green tea extracts help fight catastrophic diseases such as Alzheimer's. However, scientists have never fully understood how they work at the molecular level and how they could be harnessed to find better treatments.

Research from McMaster University is shedding new light on those underlying mechanisms. Preclinical evidence suggests that the green tea compound known as EGCG interferes with the formation of toxic assemblies (oligomers), one of the prime suspects in the early steps of the molecular cascade that leads to cognitive decline in Alzheimer's patients.

"At the , we believe EGCG coats toxic oligomers and changes their ability to grow and interact with healthy cells," explains Giuseppe Melacini, lead author and a professor in the Departments of Chemistry and Chemical Biology as well as of Biochemistry and Biomedical Sciences at McMaster, who has worked on Alzheimer's-related research for 15 years.

The findings, which are the results of a decade of advancements in (NMR) methodology and are featured in the cover page of the Journal of the American Chemical Society, could lead to new therapies and further drug discovery, say researchers.

Despite decades of research, the causes of Alzheimer's remain not fully understood, and treatment options are limited. According to the latest census numbers, seniors living in Canada now outnumber children, dramatically increasing the need for effective drugs and prevention. By some estimates, the number of Canadians with dementia is expected to rise to 937,000 by the year 2031, an increase of 66 per cent compared to current numbers.

"We all know that currently there is no cure for Alzheimer's once symptoms emerge, so our best hope is early intervention. That could mean using extracts or their derivatives early on, say 15 to 25 years before any symptoms ever set in," says Melacini.

Next, researchers hope to tackle nagging problems such as how to modify EGCG and similar molecules so they can be used effectively as a food additive, for example. EGCG is unstable at room temperature and notoriously difficult to deliver into the human body, particularly the brain.

"Food additives could prove to be a crucial therapy or adjuvant" says Melacini. "It will be important to capitalize on them early in life to increase the odds of healthy aging, in addition to exercise and a healthy lifestyle."

Explore further: Finding ways to detect and treat Alzheimer's disease

More information: Rashik Ahmed et al. Molecular Mechanism for the (−)-Epigallocatechin Gallate-Induced Toxic to Nontoxic Remodeling of Aβ Oligomers, Journal of the American Chemical Society (2017). DOI: 10.1021/jacs.7b05012

Related Stories

Finding ways to detect and treat Alzheimer's disease

February 17, 2014
Alzheimer's disease has long been marked by progress—but not the kind of progress the medical community seeks. It is the most common form of dementia among older Americans, and its risk increases with increasing age; for ...

Green tea ingredient may ameliorate memory impairment, brain insulin resistance, and obesity

July 28, 2017
A study published online in The FASEB Journal, involving mice, suggests that EGCG (epigallocatechin-3-gallate), the most abundant catechin and biologically active component in green tea, could alleviate high-fat and high-fructose ...

Green tea extract and exercise hinder progress of Alzheimer's disease in mice

May 4, 2015
According to the National Institutes of Health (NIH), Alzheimer's disease (AD) may affect as many as 5.5 million Americans. Scientists currently are seeking treatments and therapies found in common foods that will help stave ...

Study offers new insight into how Alzheimer's disease begins

November 18, 2016
A new study from The University of Texas Medical Branch at Galveston offers important insight into how Alzheimer's disease begins within the brain. The researchers found a relationship between inflammation, a toxic protein ...

Green tea and red wine extracts interrupt Alzheimer's disease pathway in cells

February 5, 2013
Natural chemicals found in green tea and red wine may disrupt a key step of the Alzheimer's disease pathway, according to new research from the University of Leeds.

Recommended for you

What really causes Alzheimer's and how might we fix it?

May 23, 2018
There have been a lot of theories about what causes Alzheimer's disease. Many of them have given rise to experimental treatments of one form or another. None of them have worked much better than taking anything you might ...

Study predicts most people with earliest Alzheimer's signs won't develop dementia associated with the disease

May 22, 2018
During the past decade, researchers have identified new ways to detect the earliest biological signs of Alzheimer's disease. These early signs, which are detected by biomarkers, may be present before a person starts to exhibit ...

Moderate to high intensity exercise does not slow cognitive decline in people with dementia

May 16, 2018
Moderate to high intensity exercise does not slow cognitive (mental) impairment in older people with dementia, finds a trial published by The BMJ today.

Mutation discovered to protect against Alzheimer's disease in mice

May 16, 2018
Researchers at the RIKEN Center for Brain Science have discovered a mutation that can protect against Alzheimer's disease in mice. Published in the scientific journal Nature Communications, the study found that a specific ...

Most deprived are nearly twice as likely to develop dementia

May 16, 2018
Older adults in England with fewer financial resources are more likely to develop dementia, according to new UCL research.

Scientists discover a variation of the genome predisposing to Alzheimer's disease

May 15, 2018
An article published in Nature Medicine shows that the inheritance of small changes in DNA alters the expression of the PM20D1 gene and is associated with an increased risk of developing Alzheimer's disease.

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.