Reactive Oxygen Species: A Key Hallmark of Cardiovascular Disease

Abstract

Cardiovascular diseases (CVDs) have been the prime cause of mortality worldwide for decades. However, the underlying mechanism of their pathogenesis is not fully clear yet. It has been already established that reactive oxygen species (ROS) play a vital role in the progression of CVDs. ROS are chemically unstable reactive free radicals containing oxygen, normally produced by xanthine oxidase, nicotinamide adenine dinucleotide phosphate oxidase, lipoxygenases, or mitochondria or due to the uncoupling of nitric oxide synthase in vascular cells. When the equilibrium between production of free radicals and antioxidant capacity of human physiology gets altered due to several pathophysiological conditions, oxidative stress is induced, which in turn leads to tissue injury. This review focuses on pathways behind the production of ROS, its involvement in various intracellular signaling cascades leading to several cardiovascular disorders (endothelial dysfunction, ischemia-reperfusion, and atherosclerosis), methods for its detection, and therapeutic strategies for treatment of CVDs targeting the sources of ROS. The information generated by this review aims to provide updated insights into the understanding of the mechanisms behind cardiovascular complications mediated by ROS.

Figure 1

Production of ROS. The figure shows the pathway of ROS production in the human body with various enzymes involved. SOD: superoxide dismutase; MPO: myeloperoxidase.

Figure 2

Sources of O₂ ^∙− and H₂O₂ in cells. The figure shows the enzymatic pathway of superoxide anion (O₂ ^∙−) and hydrogen peroxide (H₂O₂) generation in cells.