ABSTRACT
Our daily food affords us the nutritional value we need. However, the philosophy that the healthpromoting role of food may afford us more than just that its nutritional value has been recognized among the scientic community, in which many dietary components have been found to be benecial for disease prevention and treatment (Reddy 1996). Epidemiological studies suggest that a reduced risk of cancer is associated with high consumption of vegetables and fruits, which are major sources of phytochemicals and micronutrients (Reddy, Wang et al. 1997). Several phytochemicals and micronutrients present in fruits and vegetables are known to exert cancer chemopreventive
4.1 Introduction ............................................................................................................................ 55 4.1.1 Benets of Nutritional Phytochemicals in Health Improvement ................................ 55 4.1.2 Application of Nutritional Phytochemicals on Chemoprevention .............................. 56
4.2 Antioxidant Signaling Pathway and Chemoprevention .......................................................... 57 4.2.1 Carcinogenesis and Chemoprevention ........................................................................ 57 4.2.2 Reactive Oxygen/Nitrogen Species and the Body Defense of Human Diseases ........ 57 4.2.3 Antioxidant Regulation in the Health System ............................................................ 62
4.3 Nrf2, a Central Mediator of Antioxidant Response ............................................................... 62 4.3.1 Nrf2 and Antioxidant Regulation ............................................................................... 63 4.3.2 Nrf2 Regulation by Keap1 .......................................................................................... 63 4.3.3 Nrf2 Regulation under Kinase Signaling ...................................................................64
