Attenuation of Hg(II)-induced cellular and DNA damage in human blood cells by uric acid
- 1 February 2022
- journal article
- research article
- Published by Canadian Science Publishing in Biochemistry and Cell Biology
- Vol. 100 (1), 45-58
- https://doi.org/10.1139/bcb-2021-0229
Abstract
Mercury (Hg) is a widespread environmental pollutant and toxicant which induces multiple organ damage in humans and animals. Hg toxicity is mediated by the induction of oxidative stress in target cells. We have used uric acid (UA), a potent antioxidant found in biological fluids, to protect human red blood cells (RBC) and lymphocytes against Hg-mediated cell, organelle and genotoxicity. RBC were incubated with HgCl2, an Hg(II) compound, either alone or in presence of UA. Incubation of RBC with only HgCl2 increased production of nitrogen and oxygen radical species, enhanced methemoglobin levels, heme degradation, free ferrous iron, oxidation of proteins and membrane lipids and reduced antioxidant capacity of cells. UA enhanced the antioxidant capacity of RBC and restored metabolic, plasma membrane-bound and antioxidant enzyme activities. Scanning electron microscopy showed that UA prevented HgCl2-mediated morphological changes in RBC. HgCl2 dissipated the mitochondrial membrane potential and increased lysosomal membrane damage in lymphocytes, but UA pre-treatment attenuated these effects. Genotoxicity analysis by comet assay showed that UA protected lymphocyte DNA from HgCl2-induced damage. Importantly, UA itself did not exhibit any deleterious effects in either RBC or lymphocytes. Thus, UA protects human blood cells from Hg(II)-mediated oxidative damage reducing the harmful effects of this extremely toxic metal. We suggest that UA performs a similar protective role in the plasma against heavy metal toxicity.Keywords
This publication has 82 references indexed in Scilit:
- Mercury as a Global Pollutant: Sources, Pathways, and EffectsEnvironmental Science & Technology, 2013
- Global mercury emissions to the atmosphere from anthropogenic and natural sourcesAtmospheric Chemistry and Physics, 2010
- Markers of Oxidative Stress in Erythrocytes and Plasma During Aging in HumansOxidative Medicine and Cellular Longevity, 2010
- Mercury and human genotoxicity: Critical considerations and possible molecular mechanismsPharmacological Research, 2009
- Heme degradation and oxidative stress in murine models for hemoglobinopathies: Thalassemia, sickle cell disease and hemoglobin C diseaseBlood Cells, Molecules, and Diseases, 2008
- Glutamate: A potential mediator of inorganic mercury neurotoxicityMetabolic Brain Disease, 1996
- Effect of methyl mercuric chloride treatment on haematological characteristics and erythrocyte morphology of Swiss miceEnvironmental Pollution, 1991
- DNA damage by oxygen‐derived species Its mechanism and measurement in mammalian systemsFEBS Letters, 1991
- Urate and ascorbate: their possible roles as antioxidants in determining longevity of mammalian speciesArchives of Gerontology and Geriatrics, 1984
- HgCl2 increases the methemoglobin prooxidant activity. Possible mechanism of Hg2+-induced lipid peroxidation in erythrocytesChemico-Biological Interactions, 1984