H2 appears to have an immuno-modulatory effects in which it can help decrease chronic inflammation and help regulate the immune system. Also it appears it may help attenuate radiation-induced immune dysfunction.
Recent studies showed that hydrogen can be used as an effective radio-protective agent through scavenging free radicals. The immune system is one of the most important defence mechanisms against various environmental agents including ionizing radiation. Epidemiological long‐term studies have demonstrated that ionizing radiation could induce a dose‐dependent impairment of the immune response as well as a persistent inflammatory status with deregulation of cytokines production.
Reactive oxygen species (ROS) produced by cellular metabolism play an important role as signaling messengers in immune system. Modulating the level of ROS, which hydrogen gas excels at, may be important to prolong survival of T cells and enhance their anti-tumor function.
Excess ROS is immunosuppressive, facilitates tumor invasion, metastasis, and resistance. ROS are immunosuppressive participants in tumor progression. ROS production greatly contributes to inhibitory activities of tumor induced immuno suppressive cells. Therefore, ROS are not only mediators of oxidative stress, but also players of immune regulation during tumor development. Thus hydrogen inhalation would be an important therapy in Natural Immuno-Oncology.
 Protective effect of hydrogen‐rich saline against radiation‐induced immune dysfunction
Sanhu Zhao Yanyong Yang Wen Liu Zhiqiang Xuan Shouming Wu Shunfei Yu Ke Mei Yijuan Huang Pei Zhang Jianming Cai Jin Ni Yaoxian Zhao
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