Reactive Molecules Research

Studies Show Reactive Molecules Play Important Role in Our Health!

• Importance of antioxidant supplements for athletes
• Continuous regeneration of antioxidant capacity is critical
• Antioxidants may help reduce body inflammation
• Mitochondrial proteases may be directly involved in neurodegenerative diseases

Sen CK.Department of Surgery and Molecular and Cellular Biochemistry, Davis Heart and Lung Research Institute, The Ohio State University Medical Center, Columbus 43210, USA. sen-1@medctr.osu.edu

Physical exercise may be associated with a 10- to 20-fold increase in whole body oxygen uptake. Oxygen flux in the active peripheral skeletal muscle fibers may increase by as much as 100- to 200-fold during exercise. Studies during the past 2 decades suggest that during strenuous exercise, generation of reactive oxygen species (ROS) is elevated to a level that overwhelms tissue antioxidant defense systems. The result is oxidative stress. The magnitude of the stress depends on the ability of the tissues to detoxify ROS, that is, antioxidant defenses. Antioxidants produced by the body act in concert with their exogenous, mainly dietary, counterparts to provide protection against the ravages of reactive oxygen as well as nitrogen species. Antioxidant supplementation is likely to provide beneficial effects against exercise-induced oxidative tissue damage. While universal recommendations specifying types and dosages of antioxidants are difficult to make, it would be prudent for competitive athletes routinely engaged in strenuous exercise to seek an estimate of individual requirement. A new dimension in oxidant biology has recently unfolded. Although excessive oxidants may cause damage to tissues, lower levels of oxidants in biological cells may act as messenger molecules enabling the function of numerous physiological processes. It is plausible that some exercise-induced beneficial effects are actually oxidant-mediated. Such developments call for an even more careful analysis of the overall significance of types and amounts of antioxidants in diet. While these complexities pose significant challenges, experts agree that if used prudently, oxidants and antioxidants may serve as potent therapeutic tools. Efforts to determine individual needs of athletes and a balanced diet rich in antioxidant supplements are highly recommended.

Biochemical aspects of cellular antioxidant systems.Fernandez V, Videla LA.

Departamento de Bioquímica, Facultad de Medicina, Universidad de Chile, Santiago, Chile.

Aerobic life is characterized by a steady generation of reactive oxygen species balanced by a similar rate of their consumption by antioxidants. To maintain homeostasis, there is a requirement for the continuous regeneration of antioxidant capacity, and if this is not met, oxidative stress occurs, resulting in pathophysiological events. Cellular protection against oxidative stress is organized at multiple levels. Defense strategies include prevention, interception, replacement, and repair. These mechanisms are coupled to the intermediary metabolism for a continuous supply of energy, reducing equivalents, and precursors, and depend on the dietary supply of metabolic fuels and essential molecules to allow an optimal cellular functioning.