FYI Research: Researchers find clue to the `French paradox'

Despite a cuisine laden with high-fat foods, the rates of some cancers are lower in France than in America. Also, the incidence of coronary heart disease among the French is about 40 percent of that suffered by Americans.

This inconsistency -- dubbed the "French paradox" -- intrigued scientists, who suspected that a taste for wine with meals was somehow protecting the French from the ravages of disease.

Now, Carolina researchers Minnie Holmes-McNary and Albert S. Baldwin, Jr., of the Lineberger Comprehensive Cancer Center, have found a clue to the puzzle. Apparently, the French can thank trans-Resveratrol (Res), a substance found in red wine, for protecting them.

A few years ago, scientists at the University of Illinois identified the anticancer and anti-inflammatory attributes of Res, which is also abundant in mulberries, raspberries, muscadine grapes and peanuts. Holmes-McNary, a nutritional biologist, and Baldwin, a biology professor, have demonstrated how Res controls gene expression and renders cancer cells vulnerable to the protective mechanisms of the body. Their findings were reported in the July issue of Cancer Research.

Working with cultured cells from humans and rats, the researchers found that Res acts as a switch, activating a delicate chemical cascade that inhibits the activation of the protein NF-kappa B and NF-kappa B-dependent gene expression. Res seems to exert an inhibitory force on a related protein, I-kappa B, which regulates the activation of NF-kappa.

"Using Res, we were able to promote apoptosis, a process that the body uses to kill cancer and other defective cells," Holmes-McNary said. "In the absence of Res, the cancer cells continued to survive."

Baldwin first reported several years ago that NF-kappa B appears to protect cultured cancer cells from attack by anticancer chemicals. This may explain why some cancer cells withstand chemotherapy, becoming impervious to the chemical onslaught.

Holmes-McNary's and Baldwin's findings have implications for heart disease because Res also inhibited the NF-kappa B-dependent gene MCP-1, which is involved in the development of atherosclerosis.

Plans are under way to reproduce the studies using rodents. If those go well, Holmes-McNary may conduct clinical trials in several years. "This is very exciting work because we believe it explains how diet modulates changes at the molecular level," she said.

Holmes-McNary's advice to increase consumption of foods rich in Res is music to the ears of David Fussell, the owner of Duplin Winery in Rose Hill, which is the largest cooperative of scuppernong grape growers in North Carolina. The scuppernong, a muscadine grape that is native to North Carolina, tops the list of foods with high Res content.

The winery is gearing up to produce supplements made from the grape's seeds and hulls, where the Res concentration is greatest. "It's a win-win situation," Fussell said. "It will mean a great deal to our farmers and the health of people." Over the past three years, he has noted a marked increase in sales of his wines, as the beneficial properties of Res and the scuppernong's high Res content became known. The supplements, which should be available this fall, could increase the price farmers receive for scuppernong grapes by 48 percent.

Provided by Graduate Studies and Research

Writer: Janet Wagner

Editor: Neil Caudle