Oxidative stress impacts numerous physiological and pathological conditions. The excess of reactive oxygen and nitrogen species together with weakened antioxidant defense, are thought to play a significant role in the aetiology of cancer, cardiovascular, neurodegenerative, immune diseases, diabetes mellitus, obesity, aging, and others. Pro/antioxidant imbalance leads to the oxidative damage of several macromolecules, including that of DNA, proteins, and lipids that in turn support the progress of many pathologies, including mutagen formation, cell dysfunction, and inflammatory states. Many efforts have been invested in understanding the role of oxidative stress in the pathogenesis of chronic diseases. However, the effects of different strategies used to reduce oxidative stress below the threshold on the development and prevention of these conditions are still not well understood and established. These strategies include not only the effect of least understood supplementation with substances that may provide antioxidant activity, but also that of different procedures, including physical activity, exercise, or therapeutic hypothermia and hyperthermia that may in turn also generate oxidative molecules.

Therefore, it is extremely important to understand the mechanisms of operation of available and new strategies as to how do they influence the antioxidant processes and in particular, as to how do they protect cells and organs against the deleterious action of free radicals to obtain an objective of freedom from diseases. Modern populations are affected by obesity, chronic diseases, and age-related disorders such as dementia and Parkinson disease and even more. This is why expanding our knowledge regarding possible therapies and enhancing antioxidant defenses is crucial for world healthcare.

The aim of this Special Issue is to collate original research, clinical studies, and review articles describing the current findings on therapies modifying pro/antioxidant balance in health and in disease progression. We are particularly interested in articles that might contribute to better understanding the biochemical and molecular mechanisms involved in the therapeutic strategies that may decrease oxidative stress and consequently may influence the inflammatory state.

Potential topics include but are not limited to the following:

• Effects of dietary supplements and different diets on pro/antioxidant balance in humans and in animal models
• New therapies modulating oxidative stress in animal and human cell models
• Protective effects of antioxidants in experimental carcinogenesis
• Identification of pro- and antioxidant processes during anticancer treatment
• Impact of physical activity, hyperbaric therapy, cryogenic temperatures, hypo- and hyperthermia, and other conditions on oxidative stress, and endothelium as well as bone metabolism markers in humans and experimental animals
• Pro- and antioxidant processes accompanying poor nutrition, obesity, metabolic syndrome, and their treatment
• Relationship between oxidative stress and immune system under health and disease conditions