Signal Transduction Pathways Involved in the Chemo-Preventive Effect of Dietary Antioxidants: Study in HepG2 as a Cell Culture Model

Oxidative stress caused by oxygen radicals damages cellular DNA, proteins and lipids and is widely recognized as one of the causes of the development of chronic disease. There is substantial evidence that antioxidant food components have a protective role against oxidative stress-induced atherosclerosis, degenerative and age-related diseases, cancer and aging. The study of the molecular mechanisms involved in the prevention of cell damage mediated by antioxidant compounds could help to prevent appearance and development of oxidative stress related diseases. The present overview describes a model of oxidative stress in cultured cells suitable to test the signal transduction pathways involved in the chemo-preventive effect of dietary compounds. Human HepG2, a well differentiated transformed cell line from hepatic origin, is a reliable model for human hepatocytes widely used for biochemical and nutritional studies. The products selected for this overview are representative of different foodstuffs widely included in the human diet: cocoa flavonoids and olive oil hydroxytyrosol. The results confirm the reliability of the model and give more insight into the molecular mechanisms involved in the biological activity of the tested compounds.