A Comprehensive Review of Oxidative Stress as the Underlying Mechanism in Atherosclerosis and the Inefficiency of Antioxidants to Revert this Process

Abstract

Background: Cardiovascular diseases account for the highest mortality rate in the United States. The major underlying mechanism driving the onset and maintenance of cardiovascular diseases is atherosclerosis. Atherosclerosis is a chronic disease affecting large and medium-size arteries; it proceeds through four main stages along different decades of life, beginning at birth. Atherosclerosis is a consequence of oxidative stress, where homeostasis between endogenous antioxidants and reactive oxygen species is disrupted. Failure of intrinsic antioxidants and prophylactic antioxidant supplements to prevent atherosclerosis formation is an ongoing area of research in the race to avert, manage and cure atherosclerosis. Methods: The purpose of this work was to elucidate the actions of reactive oxygen species and oxidative stress on the formation of atherosclerosis as well as the different stages of atherosclerosis and the different mechanisms to prevent it. Through an extensive review of scientific literature, this paper correlates cell damage caused by oxidative stress to atheromatous plaque formation, as well as an in-depth analysis of high-density lipoproteins and enzymatic and non-enzymatic antioxidant role on atherosclerosis prevention. The antioxidant mechanism is overwhelmed by atherosclerotic processes and fails to be the ideal treatment of atherosclerosis. There is no scientific data that correlates prophylactic and non-prophylactic antioxidant treatment to a decrease in mortality or comorbidities pertaining to atherosclerosis. This is thought to be due to lack of consensus of optimal therapeutic doses, lack of reliable markers indicating which patient is to benefit from therapy and the chemical complexity of antioxidants in vivo. Current treatments for atherosclerosis include HMG-CoA reductase inhibitors which directly target low-density lipoproteins to tackle atherosclerotic plaque formation. Conclusion: HMG-CoA reductase inhibitors are not enough for the treatment of atherosclerosis given the complexity of the disease which has immune, musculoskeletal, genetic and hematologic aspects besides the involvement of lipids and lipoproteins. Therefore, other pharmacologic targets such as the PCSK9 enzyme and NFK- β should be researched in depth as possible treatments for atherosclerosis.