Comparison of Free-Radical Scavenging Activity of Various Sources of Molecular Hydrogen

Molecular hydrogen is well-known for its antioxidative and antiinflammatory properties in numerous in vitro and in vivo experiments. High-molar-mass hyaluronan (HMM HA), a natural polysaccharide present in tissues of all vertebrates, was used as a marker of the polysaccharide degradation by reactive oxygen species. The radical scavenging capacity of various sources of molecular hydrogen dissolved in water was assessed by the DPPH assay. In experiments using rotational viscometry, HMM HA was oxidatively degraded by cupric ions (1 µM) and ascorbic acid (100 µM). Further, the effects of molecular hydrogen from various sources were assessed before beginning •OH radical-induced HA degradation or one hour later, when alkyloxy- and alkylperoxy-type radical-induced HA degradation prevailed. The results of the DPPH assay showed that of the examined samples, only H2 tablet dissolved in both distilled and drinkable water mildly scavenged DPP•. In contrast, experiments from rotational viscometry showed that the inhibition of reactive oxygen species induced-hyaluronan degradation was observed when examining molecular hydrogen saturated in both distilled and drinkable water.