Green Tea Attacks Plaque

Summary: The chemical compound epigallocatechin-3-gallate (EGCG) was found to break up and dissolve protein plaques in the blood vessels that reduce the flow of blood to the heart and brain. The study: Researchers at Lancaster University, England studying the effects of EGCG have added to the growing list of areas where there is some evidence of preventive impact, ranging from breast cancer to leukemia and cardiovascular diseases.

The findings: The team has made two contributions to this body of work. The first is to identify how the molecules of EGCG break up and dissolve protein plaques in the blood vessels that reduce the flow of blood to the heart and brain. These plaques build up and are a major risk factor for heart attacks and strokes from atherosclerosis. The researchers identified the problem protein, an amyloid. These have the characteristic that they form copies that can stick together and form fibrils – in other words, they clog the arteries. They showed that EGCG can convert the fibrils to small, soluble molecules that dissolve and are eliminated in the body. The press has picked up on this result, a few even calling ECGC “the magic molecule” but in most cases they report the findings as a conditional or question: “Component found in green tea may help…” “Green tea molecule could protect…” The dominant problem in research on tea and health is while the results are suggestive, positive and consistently showing a degree of association between green tea and health, it’s not conclusive enough to meet the standards of scientific proof. Just about every paper ends with “more research is needed.” It’s here that the study makes its second contribution. It’s contained in a comment by a professor working for the sponsor of the research, The British Heart Foundation: “by engineering the molecule slightly, we might be able to make new medicines.” Tea research around the green tea-health link has moved in three historical steps, with three units. The first was the cupful as unit. Studies explored the relationship between cups of consumption and some measure of health and disease prevention. That’s pretty much accepted now. The second stage has been the chemistry, with a focus on groups of compounds: catechins (of which EGCG is one), theaflavins, antioxidants, polythenols, etc. That has sharpened understanding of the health dynamics of tea varieties. Why the research is interesting: The Lancaster study is an instance of the molecular engineering level of study. This goes below the leaf, cup, and compound to the micro-biology. The study links the EGCG molecular structure to the amyloid protein one. It’s at the molecular level that the preventive and curative powers of EGCG operate. Basically, they are attack molecules. They savage “free radical” cells – biological outlaws -- block pathways that targeted cells need to be able to grow and, as in this study, bind to, break up and dissolve malignant cells.

From a purely medical perspective, green tea is a water-based solution for delivering EGCG molecules to attack malignant cells in the body. It’s an inefficient one. The researchers stress that their finding won’t make drinking green tea curative in and of itself. EGCG biodegrades quickly in the system, and the dosage is too small to have much effect but high consumption brings risks of toxicity and tissue damage. But if the researchers succeed in tweaking the molecule “slightly” these limitations can be reduced. There are many problems in making supplements safe and effective, but the molecular engineering techniques are available and proven. Conclusions: The Lancaster study completes the three stages of (1) Does green tea help reduce heart attack? Yes, but only slightly. (2) Is there some component of green tea that provides the benefits? Yes, EGCG. (3) Do we know how it works? Yes. Now comes (4) Can we use the green tea leaf to provide the molecules and put them to work? Oh, yes. Sources: Journal of Biological Chemistry, British Heart Foundation, NCBI, British Heart Foundation, NCBI