Hydrogen Medicine Materials

ConspectusHydrogen medicine materials are defined as a new concept of biomedical materials specifically engineered to overcome critical challenges in hydrogen medicine, including exploration of biological effects and mechanisms of H2 by in vivo monitoring of H2 transportation, metabolism and transformation, enhancement of H2 therapeutic efficacy against various oxidative stress-related diseases by high-efficiency and site-specific delivery and controlled release of H2, etc. As the smallest and weakly reductive molecule, H2 exhibits some unique biological characteristics, including high tissue permeability, antioxidative stress (OS), anti-inflammation, antiapoptosis, antisenescence, pro-regeneration/pro-self-repairing, anticancer, antibiofilm, high biocompatibility, and biosafety, holding a high value of biomedical applications. However, the related biological mechanisms are not very clear. Typically, multifaceted biological behaviors of H2 in varied pathological microenvironments, such as inflammation, cancer, and injured tissue, have not been well elucidated. Moreover, as a therapeutic agent, the pharmacokinetics of H2, involving absorption, biodistribution, metabolism, and excretion, has to be clarified before clinical application, which needs the development of hydrogen bioprobes to resolve. Based on high biosafety and therapeutic validity of H2, both hydrogen gas inhalator and hydrogen-rich water generator have been clinically approved for adjuvant therapy of some respiratory and digestive system diseases including chronic obstructive pulmonary disease (COPD), hyperuricemia, hyperlipemia, gastrelcosis and coprostasis, but they hardly realize effective delivery toward remote diseased focuses. Therefore, efficient, site-specific and controlled/sustained H2-delivering materials with high biosafety urgently need to be developed for improving the outcome of hydrogen therapy. Based on these unique advantages and unsolved key issues in hydrogen medicine, hydrogen medicine materials as an emerging interdisciplinary field have attracted increasing attention in recent years.In this Account, we present a brief overview of the recent advances of hydrogen medicine materials including hydrogen bioprobes and hydrogen-delivering materials (hydrogen carriers, hydrolytic hydrogen-generating materials, and catalytic hydrogen-generating materials), as well as their typical biomedical applications including targeted inflammation therapy, targeted tumor therapy, and local tissue repair/regeneration. Finally, a forward-looking perspective on hydrogen medicine materials is demonstrated, which attempts to address the current clinical challenges in the field of hydrogen medicine. Especially, the development of small molecular bioprobes for in vivo H2 detection, the understanding of H2 pharmacokinetics and potential bioeffects, the exploration of the profound mechanisms underlying multifaceted biological behaviors of H2, the development of versatile hydrogen-delivering materials for the treatment of various intractable diseases, and the evaluation of potential long-term toxicity risk of both high-dose H2 and hydrogen-delivering materials are highlighted. This Account is expected to illuminate the way for exploration of hydrogen medicine materials.