Hydrogen nanobubbles enhancing antioxidant activity of glutathione peroxidase: Superiority at the nanoscale over molecular scale

As novel antioxidants, hydrogen nanobubbles (NBs) intricately regulate the growth and developmental processes of organisms, bolstering their tolerance to external stresses. Despite their recognized potential, the precise antioxidative mechanisms remain inadequately elucidated. In this study, we present evidence supporting the protective role of hydrogen NBs in an oxidative stress system, utilizing Cu²⁺ as a prototypical inducer and Tetrahymena thermophila as a representative model organism. To elucidate the molecular mechanism of this phenomenon, we employed a comprehensive approach, integrating transcriptomic analysis and molecular dynamics simulations. Additionally, intrinsic differential scanning and surface plasmon resonance techniques were applied to unveil the molecular-level response and nanoscale interactions. Our investigation revealed that hydrogen NBs induce a notable upregulation in the expression of glutathione peroxidase (GPx). Moreover, compared to molecular hydrogen, hydrogen NBs have a more pronounced effect on the structural reconfiguration and catalytic efficacy of GPx, as demonstrated by the greater reduction in the distance between the catalytic center amino acids and a significant increase in GPx’s affinity for GSH. In summary, our findings underscore GPx as the targeted molecules through which hydrogen NBs exert their antioxidative effects. These insights contribute to a deeper comprehension of the molecular implications of hydrogen NBs and provide new perspectives for alleviating the toxicity of environmental pollutants.