Antioxidant strategies in protection against neurodegenerative disorders

The most common neurodegenerative diseases include Alzheimer's disease, Parkinson's disease and stroke; they are devastating clinical problems which lack effective treatments. Although the aetiology of these diseases is not fully understood, oxidative stress is believed to be a contributing causative factor. In addition to conventional therapies, antioxidant strategies in protection against neurodegenerative conditions have been increasingly addressed, as evidenced by an increasing number of animal studies, clinical reports and patents regarding these processes in recent years. The effectiveness of antioxidants in protecting against neurodegenerative disorders lies mainly in their ability to cross the blood-brain barrier, their potential in terms of subcellular distribution occurring in membranes, in the cytoplasm and especially in mitochondria, and their multifunctional capacity as well as their synergistic actions. The naturally occurring antioxidants with different properties collaborate as an array to defend against oxidative stress. Single antioxidant supplementation would not then be expected to have a remarkable influence on neurodegenerative diseases, which may involve free radicals. Thus, using combinations of antioxidants with different subcellular distributions and different properties for prophylaxis or treatment would probably improve therapeutic outcomes. Based on their multifactoral aetiology, the development of novel antioxidants with anti-inflammatory and metal-chelating properties and the ability to improve metabolism, for example by increasing ATP production rate or a new formulation of antioxidants with other agents, which have different functions, will become the new strategies in protecting against neurodegenerative disorders.