水素化マグネシウムによる一酸化窒素シグナルを介したアルファルファの銅耐性付与機構
Magnesium hydride (MgH₂), a solid-state hydrogen source, was investigated for its biological role in plants under copper (Cu) stress. Administration of MgH₂ to alfalfa seedlings reduced root growth inhibition caused by Cu toxicity. Using aged MgH₂ as a negative control, the protective effect was attributed specifically to released molecular hydrogen rather than to magnesium metabolites or pH changes. MgH₂ enhanced Cu-induced nitric oxide (NO) production, with nitrate reductase identified as a primary contributor to this NO generation. Cu accumulation in root tissues was markedly decreased, while non-protein thiol content increased and Cu deposition in cell walls was elevated, collectively explaining the NO-mediated alleviation of Cu toxicity. Antioxidant enzyme activities were restored, and reactive oxygen species accumulation along with oxidative damage were reduced, as confirmed by histochemical and biochemical analyses. Blocking endogenous NO with a scavenger abolished these protective responses, confirming the central role of NO signaling. These findings suggest that solid-state hydrogen materials may have practical applications in agricultural settings.
H₂ released from MgH₂ enhances nitric oxide production via nitrate reductase, reduces Cu accumulation in root tissues by increasing non-protein thiols and promoting Cu deposition in cell walls, and restores redox balance by modulating antioxidant enzyme activities and suppressing reactive oxygen species.
This is basic research at the cellular or molecular level. For human application, inhalation is the most promising delivery route, but inhalation carries explosion risk and concentration matters (empirical LFL of 10%; high-concentration devices are not recommended).
See also:
https://h2-papers.org/en/papers/35032725