Evidence Shows Red Wine Antioxidant Kills Cancer
— Rochester
researchers showed for the first time that a natural antioxidant found in grape
skins and red wine can help destroy pancreatic cancer cells by reaching to the
cell''s core energy source, or mitochondria, and crippling its function. The new
study also showed that when the pancreatic cancer cells were doubly assaulted
-- pre-treated with the antioxidant, resveratrol, and irradiated -- the
combination induced a type of cell death called apoptosis, an important goal of
cancer therapy.
The research has many implications for patients, said lead author Paul
Okunieff, M.D., chief of Radiation Oncology at the James P. Wilmot Cancer
Center at the University
of Rochester Medical Center. The study is published in the March edition of the
journal, Advances in Experimental Medicine and Biology.
Yet despite widespread interest in antioxidants, some physicians are
concerned antioxidants might end up protecting tumors. Okunieff''s study showed
there is little evidence to support that fear. In fact, the research suggests
resveratrol not only reaches its intended target, injuring the nexus of
malignant cells, but at the same time protects normal tissue from the harmful
effects of radiation. Resveratrol is known for its ability to protect plants
from bacteria and fungi. Purified versions have been described in scientific
journals as potential anti-cancer, anti-inflammatory and anti-atherogenic
agents, and for their ability to modulate cell growth. Other well-known antioxidants
derived from natural sources include caffeine, melatonin, flavonoids,
polyphenols, and vitamins C and E. The discovery is critical because, like the
cell nucleus, the mitochondria contains its own DNA and has the ability to
continuously supply the cell with energy when functioning properly. Stopping
the energy flow theoretically stops the cancer.
Researchers divided pancreatic cancer cells into two groups: cells treated
without resveratrol, or with resveratrol, at a relatively high dose of 50
mg/ml, in combination with ionizing radiation.
(The resveratrol concentration
in red wine can be as high as 30 mg/ml, the study said, and higher doses are
expected to be safe as long as a physician is monitoring.) They evaluated the
mitochondria function of the cells treated with resveratrol, and also measured
apoptosis (cell death), the level of reactive oxygen species in the cells, and
how the cell membranes responded to the antioxidant.
Laboratory experiments showed that resveratrol:
Reduced the function of proteins
in the pancreatic cancer cell membranes that are responsible for pumping
chemotherapy out of the cell, making the cells chemo-sensitive.Triggered the production of
reactive oxygen species (ROS), which are substances circulating in the
human body that have been implicated in a number of diseases: when ROS is
increased, cells burn out and die. Caused apoptosis, which is
likely the result of increased ROS.Depolarized the mitochondrial
membranes, which indicates a decrease in the cell''s potential to function.
Radiation alone does not injure the mitochondrial membrane as much.
The team also wanted to investigate why pancreatic cancer cells seem to be
particularly resistant to chemotherapy. The pancreas, a gland located deep in
the abdomen, produces insulin and regulates sugar, and pumps or channels
powerful digestive enzymes into the duodenum. This natural pumping process,
however, ends up ridding the needed chemotherapy from cells in the pancreas.
But just as reseveratrol interferes with the cancer cells'' energy source, it
also may decrease the power available to pump chemotherapy out of the cell..