Can vitamin C supplementation reverse the effects of exercise training in polluted air on oxidative stress markers? A randomized controlled trial

• Published in: ARYA atherosclerosis 2021-01, Vol.17 (1), p.1-9
• Main Authors: Eatemadyboroujeni, Amin, Karqarfard, Mehdi, Alaei, Hojatollah
• Format: Article
• Language: English
• Subjects: aerobic exercise; Air pollution; malondialdehyde; Mortality; Original; Oxidation; Oxidative stress; oxidized low-density lipoprotein; Vitamin C; Vitamin E
• ISSN: 1735-3955; 2251-6638
• DOI: 10.22122/arya.v17i0.2101

[...]polluted air significantly increased OxLDL levels in both exercise in polluted air groups. Keywords: Aerobic Exercise; Air Pollution; Vitamin C; Malondialdehyde; Oxidized Low-Density Lipoprotein Date of submission: 09 Jan. 2020, Date of acceptance: 12 Sep. 2020 Introduction Huge amounts of pollutants are produced by vehicles and released into the air every day, especially carbon monoxide (CO), sulfur dioxide (SO2), and nitrogen dioxide (NO2).1 Everybody is endangered by air pollution, but some are more at risk.2 During exercise, several physiological changes occur that could exacerbate the effects of air pollution on health. Vitamin C (ascorbic acid), which is water-soluble and present in the cytosolic compartment of the cell, serves as an electron donor to vitamin E radicals generated in the cell membrane during oxidative stress.12 It is a major water-soluble antioxidant that is an effective scavenger of reactive oxygen species in both intracellular and extracellular fluids. MDA's reactions with lysine residues generate lysine-lysine cross-link, which has been identified in apolipoprotein B (apoB) fractions of oxidized low-density lipoprotein (OxLDL) and is postulated to impair the interaction between OxLDL and macrophages, and thereby, to promote atherosclerosis.16,17 The oxidation of LDL, which leads to the creation of OxLDL and phospholipids, plays a central role in the pathogenesis of atherosclerosis, with the adducts being both pro-atherogenic and pro-inflammatory.18 OxLDL levels are higher in patients with CVD, and increasing OxLDL levels correlate with increasing severity of disease (e.g., stable angina vs. unstable angina vs. myocardial infarction).19 OxLDL levels also appear to be predictive of future CAD in apparently healthy men.20 The epidemiological association between exposure to air pollution and cardiovascular morbidity and mortality has been well documented in previous studies.21 Furthermore, long-term regular physical activity is significantly associated with a reduced risk of cardiovascular events.22 Habitual physical exercise benefits health and longevity across the life span; however, some researchers have recently noted the possible exposure to increased risk of air contaminants during exercise since exercise amplifies respiratory uptake and deposition of air pollutants in the lung and ambient air pollution affects health.23 Therefore, the cardiovascular health benefits of exercise may be countered to some degree by harmful acti