UNIVERSITY PARK, Pa. — Barry Halliwell, a senior adviser to the president, will present the Healthy Lion Award Seminar, co-sponsored by Penn State's Center of Excellence for Plant and Mushroom Foods for Health and the Department of Food Science.
The seminar, which is open to the public, will take place from 5 to 6 p.m. Oct. 5 in Berg Auditorium, located in the Life Sciences Building on the University Park campus. A reception will take place at 4 p.m. on the building's bridge.
Halliwell, Tan Chin Tuan Centennial Professor at National University of Singapore, is one of the world's leading scientists on the subject of free radicals, antioxidants and aging. During the seminar — titled "The Benefits of Antioxidants, Fact or Fiction?" — Halliwell will explain how oxygen free radicals and related "reactive oxygen species" are fundamental to survival.
"They help drive evolution, yet the damage that they can do — 'oxidative damage' — is involved in most, if not all, human diseases and in aging itself," he said. "The fact that reactive oxygen species cause such harm while playing important pathophysiological roles can be explained by Darwinian medicine."
Halliwell's research team helped elucidate the key roles played by transition metals (especially iron) in oxidative damage as well as the pathway used by plants to remove H2O2, known as the ascorbate-glutathione cycle. Plants are key to human life, he pointed out.
"They supply us with oxygen and provide a variety of nutrients with antioxidant abilities, and diets rich in plants lower the risk of developing many diseases, including diabetes, atherosclerosis, dementias and stroke," he said. "Exactly why is uncertain."
Halliwell will discuss the reasons for the general lack of effectiveness of such "classical" antioxidant supplements as ascorbate, vitamin E and beta-carotene in decreasing risk or severity of human disease in intervention studies. One explanation, he said, is that antioxidants are often ineffective in decreasing levels of oxidative damage in humans.
These antioxidants work better in cell culture and in rodent models (which questions the relevance of some mouse models of human disease, and cell culture studies can generate many errors). Halliwell will explain how we can minimize oxidative damage in the human body and will present strategies to accomplish that goal. Studies on lifespan and healthspan using C. elegans as a model will also be presented.
"Much of our research now focuses on ergothioneine, a diet-derived antioxidant that is avidly retained by the human body and particularly accumulated at sites of tissue injury, where it may help to diminish tissue damage," he said. "We have conducted a detailed study of how ergothioneine behaves when administered to humans. Ergothioneine is made by fungi and some bacteria, although the list of these able to make it grows daily."
More information on the Healthy Lion Award Seminar and the Center of Excellence for Plant and Mushroom Foods for Health, which is housed in the College of Agricultural Sciences, is available online.