Development of Iron-Chelating/Antioxidant Nutraceuticals and Natural Products as Pharmaceuticals for Clinical Use in...

Antioxidant activity is a normal physiological function that is essential for healthy living, and it is maintained by antioxidant dietary nutrients. However, increases in free radical production and oxidative toxicity in many clinical conditions can cause serious and sometimes irreversible damage. Despite many investigations, including hundreds of clinical trials suggesting that there are health benefits obtained from the use of natural antioxidants, no antioxidant drugs have yet been developed for the treatment of any disease associated with free radical pathology. Millions of people choose to use nutraceutical and natural product antioxidants as therapeutics and also for chemoprevention against cancer and other diseases. New academic efforts and strategies are required for the development of antioxidant drugs in clinical practice in the absence of interest by the pharmaceutical and nutraceutical industries. One of the most effective antioxidant therapeutic strategies is inhibition by chelators of iron involved in the catalytic formation of free radical reactions and their associated damage. Hundreds of phytochelators have been shown to inhibit oxidative damage, similar to the iron-chelating drugs deferiprone and deferoxamine. In particular, several nutraceuticals and natural products such as ascorbic acid, quercetin, curcumin, fisetin, lipoic acid, and maltol have been shown to have high antioxidant activity and iron-binding capacity, as well as other effects on iron metabolism, in pre-clinical studies and clinical trials involving different categories of patients. For example, ascorbic acid and maltol-iron complexes are sold as pharmaceutical products for the treatment of iron deficiency. The development of nutraceuticals as antioxidant drugs may involve one or more applications, such as short- or long-term treatments, single-drug or combination therapies, and also different targets, such as the prevention, treatment, or post-treatment of diseases associated with free radical pathology as well as ferroptosis. The academic efforts surrounding the developments of iron-chelating nutraceuticals or natural products into antioxidant pharmaceuticals should fulfill all of the regulatory requirements and include clinical tests of antioxidants in rare or untreatable diseases, as well as the involvement of government translational research institutions and expert groups that specialize in regulatory drug affairs, among others.