Reactive oxygen species: from health to disease

Abstract

Upon reaction with electrons, oxygen is transformed into reactive oxygen species (ROS). It has long been known that ROS can destroy bacteria and destroy human cells, but research in recent decades has highlighted new roles for ROS in health and disease. Indeed, while prolonged exposure to high ROS concentrations may lead to non-specific damage to proteins, lipids, and nucleic acids, low to intermediate ROS concentrations exert their effects rather through regulation of cell signalling cascades. Biological specificity is achieved through the amount, duration, and localisation of ROS production. ROS have crucial roles in normal physiological processes, such as through redox regulation of protein phosphorylation, ion channels, and transcription factors. ROS are also required for biosynthetic processes, including thyroid hormone production and crosslinking of extracellular matrix. There are multiple sources of ROS, including NADPH oxidase enzymes; similarly, there are a large number of ROS-degrading systems. ROS-related disease can be either due to a lack of ROS (e.g., chronic granulomatous disease, certain autoimmune disorders) or a surplus of ROS (e.g., cardiovascular and neurodegenerative diseases). For diseases caused by a surplus of ROS, antioxidant supplementation has proven largely ineffective in clinical studies, most probably because their action is too late, too little, and too non-specific. Specific inhibition of ROS-producing enzymes is an approach more promising of clinical efficacy.

Sinapinic and protocatechuic acids found in rapeseed: isolation, characterisation and potential benefits for human health as functional food ingredients

“…High levels of ROS are known to be carcinogenic, damaging vital cellular components including lipids, proteins and DNA. Given the destructive potential of ROS, it is generally thought that the use of antioxidants could reduce intracellular ROS levels and thus alleviate ROS-mediated damage (Brieger et al, 2012). Recent studies indicate the antioxidant activity of SA and SA's superoxide radical and hydroxyl radical, as well as its -O 2…”

Metabolic stability of superoxide adducts derived from newly developed cyclic nitrone spin traps

“…Reactive oxygen species (ROS) are important mediators in aging [1] , cell signaling under physiological and pathological conditions such as inflammation, cancers, and neurodegenerative diseases [2,3] . Superoxide radical anion (O 2 -) is a major contributor to oxidative stress, as it is the origin of damaging species such as H 2 O 2 , HO .…”

Comparison Between the Phytochemical and Antioxidant Properties of Plants Used in Plant Infusions for Medicinal Purposes

“…The current state of medical knowledge attributes to antioxidant molecules a crucial role in counteracting the effects of oxidative stress caused by Reactive Oxygen Species (ROS), such as superoxide anions, hydrogen peroxide, and hydroxyl, nitric oxide and peroxynitrite radicals. It is now recognized that oxidative stress is related to the pathogenesis of several diseases such as metabolic syndrome, cancer and degenerative disorders (Alfadda & Sallam, 2012;Brieger et al, 2012;Finkel, 2000). The oxidation of lipids, proteins, DNA, carbohydrates, and other biological molecules by toxic ROS may cause DNA mutations and/or damage target cells and tissues, and this often results in cell senescence and death.…”