A chemical found in red wine remains effective at fighting cancer even after the body's metabolism has converted it into other compounds, a new study has claimed.
Researchers at the University of Leicester's Department of Cancer Studies and Molecular Medicine found that resveratrol - a compound extracted from the skins of red grapes - is not rendered ineffective once it is metabolised by the body.
Resveratrol is metabolised very quickly and it had previously been thought that levels of the extracted chemical drop too quickly to make it usable in clinical trials.
The new research shows that the chemical can still be taken into cells after it has been metabolised into resveratrol sulfates.
Enzymes within cells are then able to break it down into resveratrol again - meaning that levels of resveratrol in the cells are higher than was previously thought.
In fact, the results appear to show resveratrol may be more effective once it has been generated from resveratrol sulfate than it is if it has never been metabolised because the
concentrations achieved are higher.
The team, led by University of Leicester translational cancer research expert Professor Karen Brown, administered resveratrol sulfate to mice models.
They were subsequently able to detect free resveratrol in plasma and a variety of tissues in the mice. This is the first direct sign that resveratrol can be formed from resveratrol sulfate in live animals, and the researchers think it may help to show how resveratrol is able to have beneficial effects in animals.
The study also showed that resveratrol generated from resveratrol sulfate is able to slow the growth of cancer cells by causing them to digest their own internal constituents and stopping them from dividing.
"It has been known for many years that resveratrol is rapidly converted to sulfate and glucuronide metabolites in humans and animals - meaning the plasma concentrations of
resveratrol itself quickly become very low after administration," Brown said.
"Our study was the first to show that resveratrol can be regenerated from sulfate metabolites in cells and that this resveratrol can then have biological activity that could be useful in a wide variety of diseases in humans.
"There is considerable commercial interest in developing new forms of resveratrol that can resist or overcome the issue of rapid metabolism. Our results suggest such products may not
actually be necessary to deliver biologically active doses of resveratrol to people," she said.
The study was published in the journal Science Translational Medicine