A specific antioxidant found in green tea may be able to prevent the onset of a rare condition associated with multiple myeloma and amyloidosis. Epigallocatechin gallate (EGCG) is a polyphenol found in green tea that is proving itself to be a powerful anticarcinogenic. A study published last year found that EGCG can affect protein buildup in the bone marrow, preventing it from becoming misshapen and replicating. The research was published in the Journal of Biological Chemistry.
Systemic light chain amyloidosis (AL) can affect patients with multiple myeloma or amyloidosis. Both diseases affect the bone marrow, disrupting normal function. To date, there is no cure for either disease. AL occurs when abnormal plasma cells in the bone marrow make too many light chains. All healthy antibodies contain two short light chains and two longer heavy chains. In light chain amyloidosis, the excess of light chains clump together and become a substance called an amyloid. This abnormal protein can then build up in an organ leading to failure. For example, an amyloid buildup in the heart can cause congestive heart failure whereas an amyloid in the kidney can result in poor kidney function. AL is the most common form of systemic amyloidosis and has a high occurrence rate among multiple myeloma patients.
This breakthrough study concludes that EGCG transforms light chain amyloids. Dr. Jan Bieschke, the lead author, and his colleagues previously examined EGCG’s potential effects in Alzheimer’s and Parkinson’s patients. The polyphenol, also known as Epigallocatechin-3-gallate, prevented the buildup of protein in both diseases. Results of the latest study showed similar effects. “In the presence of green tea, the chains have a different internal structure. The ECGC [sic] pulled the light chain into a different type of aggregate that wasn’t toxic and didn’t form fibril structures, as happens to organs affected by amyloidosis,” says Dr. Bieschke.
Dr. Bieschke and his team are currently reviewing the mechanism of the EGCG in a test tube. He concludes, “we are studying how it works on a foundational level. At the same time, clinical trials at the Amyloidosis Center in Heidelberg, with Alzheimer’s in Berlin and with the Parkinson’s in China examine the process in people. We all want this compound to work in a patient.”
Tea is the most popular beverage in the world, aside from water. It is composed of alkaloids, amino acids, and several polyphenols. It is the last component that is thought to be responsible for the various health benefits attributed to tea, especially those of the green variety.
The predominant polyphenol in tea, EGCG, has been linked to cancer prevention and treatment. The antioxidant properties of EGCG inhibit tumor growth. Cancer cells form when the cellular growth cycle is affected. When this happens, uncontrollable amounts of cells begin to grow, building up to tumors. EGCG blocks enzymes needed by cancer cells to maintain their so-called “cell cycle.” This forces the cancer cells to go into “growth arrest.”
EGCG can also induce apoptosis (cell death). One study suggests that EGCG influences abnormal cells to commit “suicide” by triggering a specific protein activity within these cells. In the study, breast cancer cells were treated with EGCG. Researchers say these cells died in such a large amount as to cause a significant reduction in tumor size.
Furthermore, tea has been shown to improve immune system function, prevent ultraviolet radiation damage, and promote detoxification.
As with Dr. Bieschke’s study, most of the effects of green tea have been found in laboratory studies. Human clinical trials need to be carried out in order to fully determine the effects of EGCG in the prevention of cancer. That being said, all available evidence still suggests that a daily consumption of around two to three cups of tea can lower cancer risk.