Reactive oxygen species in biological systems: Pathways, associated diseases, and potential inhibitors—A review

Abstract

Reactive oxygen species (ROS) are produced under normal physiological conditions and may have beneficial and harmful effects on biological systems. ROS are involved in many physiological processes such as differentiation, proliferation, necrosis, autophagy, and apoptosis by acting as signaling molecules or regulators of transcription factors. In this case, maintaining proper cellular ROS levels is known as redox homeostasis. Oxidative stress occurs because of the imbalance between the production of ROS and antioxidant defenses. Sources of ROS include the mitochondria, auto‐oxidation of glucose, and enzymatic pathways such as nicotinamide adenine dinucleotide phosphate reduced (NAD[P]H) oxidase. The possible ROS pathways are NF‐κB, MAPKs, PI3K‐Akt, and the Keap1‐Nrf2‐ARE signaling pathway. This review covers the literature pertaining to the possible ROS pathways and strategies to inhibit them. Additionally, this review summarizes the literature related to finding ROS inhibitors.

Insights into the Management of Chronic Hepatitis in Children—From Oxidative Stress to Antioxidant Therapy

“…It is widely recognized that the liver is involved in numerous metabolic activities via mitochondrial and microsomal systems. These typical metabolic activities result in the physiological production of reactive oxygen species (ROS) in hepatocytes [6]. As a defense mechanism, the organism utilizes antioxidant molecules such as catalase (CAT) and superoxide dismutase (SOD) [7], and lipid peroxidation causes an increase in malondialdehyde (MDA), a biomarker closely related to hepatocyte destruction [8].…”