Abstract
Free radicals are very damaging to cell membranes, proteins, lipids and deoxyribonucleic acid. Oxidative damage caused by the free radicals accumulates with age and is considered to be a major contributor to ageing and the development of degenerative diseases (e.g. eye disorders, inflammatory disease, rheumatoid arthritis, immune system decline, chronic obstructive lung disease, atherosclerosis, the Parkinson disease, the Alzheimer disease, some types of cancer). Therefore, defense against free radical damage seems to be important in maintaining structural and functional integrity of the endothelium and its cell types. Fortunately, to prevent free radical production, the human body is equipped with an array of antioxidant defense mechanisms to combat free radical damage. Providing proper antioxidant protection is a challenge similar to putting pieces of puzzle together. All the necessary pieces must be available and properly combined to create a comprehensive and balanced protection. The antioxidant system has many components. A deficiency in any of these components can cause a reduction in overall antioxidant status of an individual. Medical scientists have been trying to piece together the underlying cause of ageing and diseases. This implies that this topic needs to be studied further. So keeping all this in mind, besides of different causes, decreased total antioxidant status may be responsible for all above conditions. More studies on larger population are underway to determine whether these tendencies are real. At present we can not predict whether or not there is relevant dysfunction of the antioxidant enzymes and what role if any such a dysfunction would play in the development of different diseases.