The novel antioxidant TA293 reveals the role of cytoplasmic hydroxyl radicals in oxidative stress-induced senescence and inflammation

Hydrogen Indirectly Suppresses Increases in Hydrogen Peroxide in Cytoplasmic Hydroxyl Radical-Induced Cells and Suppresses Cellular Senescence

“…In recent studies using H 2 gas and H 2 water, H 2 was found to be useful for the treatment of various geriatric diseases involving oxidative stress [1]. In a previous study using cyto •OH scavenger TA293, we demonstrated that cyto •OH induced cellular senescence in vitro and in vivo [2]. In this study, similar to TA293, we found that H 2 suppressed the cellular senescence of pyocyanin-stimulated cells.…”

“…In addition, suppressed cell death of dopaminergic neurons in a Parkinson’s disease animal model [24,25], prevention of atherosclerosis in an apolipoprotein E knockout (apoE KO) mouse [26], and suppressed mild cognitive impairment in a dementia animal model [27] provide supporting evidence for in vivo effects. Cyto •OH scavenging is also known to suppress cellular senescence and inflammation [2]. Moreover, NO, O 2 − , and the •OH scavenger phloroglucinol suppress H 2 O 2 -induced premature senescence and inhibit lipid peroxidation [28].…”

“…Western blotting was conducted following the same procedures described in a previous study [2] using primary antibodies against p16Ink4a (Bioworld Technology, St. Louis Park, MN, USA), p21Waf1/Cip1 (Santa Cruz Biotechnology, Dallas, TX, USA), ATF4, p-p53 ser15 , p-eIF2α ser51 , β-actin (Cell Signaling Technology, Beverly, MA, USA), p-ATM ser1981 (Rockland Immunochemicals Inc., Limerick, PA, USA), and HRI (Millipore, Sydney, Australia) diluted 1:1000. After incubation with horseradish peroxidase (HRP)-linked secondary antibodies diluted 1:2000 (Cell Signaling Technology), signals were detected using ECL Plus Western Blotting Detection Reagents (GE Healthcare Life Sciences, Marlborough, MA, USA).…”

“…Oxidative DNA damage in MEFs was evaluated by first extracting the DNA using the DNA Extractor TIS Kit (JaICA, Shizuoka, Japan) according to the manufacturer’s instructions. DNA damage was assessed by measuring 8-hydroxy-2-deoxyguanosine (8-OHdG) using the 8-OHdG EIA kit (JaICA) according to the manufacturer’s instructions, as previously described [2].…”

“…Recent research has shown that H 2 specifically neutralizes hydroxyl radicals (•OH), which have the strongest oxidizing power among reactive oxygen species (ROS) [1]. Recently, it was suggested that •OH located in the cytoplasm (cyto •OH), unlike •OH localized in the mitochondria (mito •OH), is one of the inducers of cellular senescence [2]. Senescent cells accumulate in aged tissues, and elimination of senescent cells suppresses tissue and organ dysfunction [3].…”