Free Radicals and Antioxidants in Human Diseases: A Review

Intensive oxidative processes occurring in human organisms lead to formation of reactive oxygen species (ROS), which can damage systemic cells and tissues. ROS are well recognised for playing a dual role, being both deleterious and beneficial species. They are mainly derived from oxygen (ROS) and generated in our body through various endogenous systems, exposure to different physic-chemical conditions or pathophysiological states. ROS can adversely alter lipids, proteins and DNA and are implicated in ageing and in several human diseases. Antioxidants appear to be the first line of defence against free radical damage, and are vital for maintaining optimum health and well-being. This review describes the ROS-linked pathogenesis of cancer, heart diseases, ischaemia/reperfusion injury, diabetes mellitus, neurodegenerative diseases (Alzheimer's disease and Parkinson's disease) and ageing.