Review Article

Combating Oxidative Stress and Inflammation in COVID-19 by Molecular Hydrogen Therapy: Mechanisms and Perspectives

Figure 2

Possible mechanisms of alleviation properties of molecular hydrogen on COVID-19 patients. OH: hydroxyl radical; O2-: superoxide anion; ONOO-: peroxynitrite anion; H2O2: hydrogen peroxide; H2: molecular hydrogen; NOX: nicotinamide adenine dinucleotide phosphate (NADPH) oxidase; AMPK: 5 adenosine monophosphate- (AMP-) activated protein kinase; MAPK: mitogen-activated protein kinase; PI3K: phosphatidylinositol 3-kinase; Keap1: Kelch-like ECH-associated protein 1; Nrf2: nuclear factor erythroid 2-related factor 2; MAF: small MAF protein; ARE: Nrf2-antioxidant response element; SOD: superoxide dismutase; CAT: catalase; GPx: glutathione peroxidase; P53: tumor protein; Bax: BCL2-associated X protein; Bcl-2: B-cell lymphoma 2 protein; Bcl-XL: B-cell lymphoma–extra-large protein; IL-12: interleukin 12; IL-1β: interleukin 1-beta; IL-6: interleukin 6; IL-8: interleukin 8; TNF-α: tumor necrosis factor α; NF-κB: nuclear factor-kappa-light-chain-enhancer of activated B cells.