They Discover Another Anticancer Property Of Green Tea

Green tea was known to contain antioxidant polyphenols that fight free radicals that can damage DNA. But now it has been discovered that these polyphenols can act directly on the correct expression of a gene that protects against the development of half of the cancers.

Chunyu Wang, lead author of the study and professor of biological sciences at Rensselaer Polytechnic Institute, says they have found a previously unknown direct interaction between antioxidant activity and epigenetics, which may also pave the way for the development of new anticancer drugs.

“Our work helps explain how epigallocatechin gallate 3 (EGCG) in green tea can drive the anticancer activity of the P53 gene,” says Chunyu Wang.

Green tea collaborates with the gene “guardian of the genome”

Chunyu is an expert in the use of nuclear magnetic resonance spectroscopy to study specific mechanisms in Alzheimer’s disease and cancer, including the P53 gene, which expresses a protein that he describes as “the most important in human cancer.”

The P53 gene, a “tumor suppressor, “ known as “the guardian of the genome,” has several well-known anticancer functions, including stopping cell growth to allow DNA repair, activating DNA repair, and initiating programmed cell death. (apoptosis), if DNA damage cannot be repaired.

EGCG is a natural antioxidant, which means that it helps undo the almost constant damage caused by oxygen metabolism. It is found in abundance in green tea and can also be consumed as a supplement.

Green tea protects a natural anticancer protein

Wang’s team found that the interaction between EGCG and P53 preserves the protein from degradation. Generally, after being produced in the body, p53 is rapidly degraded when its “N-terminal domain” interacts with a protein called MDM2. This regular cycle of production and degradation keeps p53 levels in constant decline.

But when EGCG from green tea binds to P53, it prevents the degrading action of MDM2, so the level of anticancer protein increases.

The study, published in the scientific journal Nature Communications, involved researchers from centers in the United States and China and was conducted with the support of multiple grants from the United States National Institutes of Health.

Green tea is also anti-inflammatory

EGCG therefore adds a clear anti-cancer action to its already known anti-inflammatory properties that are beneficial for the cardiovascular system, for the brain and for metabolism (it contributes to the prevention of diabetes and obesity within the framework of a healthy diet) .

The main food source of EGCG is green tea, but it is also found in small amounts in berries, kiwis, peaches, apples, avocados, pecans, pistachios, and hazelnuts.

A cup of green tea contains 50 to 100 mg of EGCG. A review of studies published in the journal Regulatory Toxicology and Pharmacology estimates that an adequate dose for adults is 338 mg daily.

Matcha tea is the richest in EGCG

Different varieties of green tea can contain EGCG in different proportions. Matcha tea, which is obtained from plants that grow in the shade and is consumed as a powder dissolved in water, is the richest in EGCG.

The dose per cup of matcha tea is 1 or 2 grams and it is recommended to take 3 or 4 grams daily in 2 or 4 cups.

How to prepare the infusion of green tea leaves

When preparing the infusion of loose leaves of green tea, it is recommended that the water does not exceed 70 ºC of temperature and the two minutes of infusion.

Then a second infusion can be prepared with the same leaves, but at a higher temperature (90 ºC) and for 5-10 minutes. In this way, the maximum EGCG will be extracted from the leaves without the drink becoming too bitter.

Animal milk should not be added to green tea, because EGCG binds to protein, reducing its absorption.

Although it is a beneficial and very safe compound , EGCG must not exceed 700 mg daily, as it could increase blood levels of transaminases, which indicate liver damage.

Scientific references:

• Chunyu Wang et al. EGCG binds intrinsically disordered N-terminal domain of p53 and disrupts p53-MDM2 interaction. Nature Communications.
• Andrew Shao. The safety of green tea and green tea extract consumption in adults – Results of a systematic review. Regulatory Toxicology and Pharmacology.