Antioxidant

Antioxidants can be classified into enzymes, vitamins, small molecule antioxidants and plant phytochemicals. They either scavenge ROS or convent more harmful species to a lesser one. Some antioxidants such as vitamin E. C. can only be obtained via diet; some trace elements such as copper, zink, manganese and selenium are essential in the formation of antioxidant enzymes. One of our primary interest is to study how antioxidant enzymes are regulated by exercise, nutrient intake, disease, and aging.

Phytochemicals are organic molecules in plants (vegetables, fruits, grain, herbs, etc.) that demonstrate biological functions useful to human. Ginsenoside (ginseng), resveratrol (grape), catechin (tea), isoflavon (soy) are known to most people. Recent research indicates that these compounds serve not only as antioxidants but properties such as DNA binding, anti-inflammation, cancer-inhibiting, just to list a few. Currently our lab is studying anti-inflammatory function of avenanthramide, in oats and oleocanthal in olive oil, both at the gene level to explore their mechanism of action and in clinical trials to learn their efficacy in human.

Avenanthramides (AVA) are a group of diphenolic acids only found in oats. AVA have shown antioxidant anti-inflammatory and anti-atherogenic effects. These effects were shown to be derived from decreased NFκB activity. AVA is bioavailable to animal and human. Supplementation of AVA has been shown to inhibit plasma inflammatory markers induced by eccentric exercise.

Ginseng has demonstrated potent antioxidant function in vitro and in vivo that is largely attributed to the glycoside saponins (ginsenosides) content in the herb. Ginseng supplementation has been shown to reduce oxidative damage and increase antioxidant enzyme activities in numerous animal and human studies. We have shown that rats fed a diet fortified with ginseng had increased antioxidant enzyme activities and decreased protein oxidation in heart and skeletal muscles, and aged women supplemented with ginseng capsules daily increased plasma antioxidant capacity.