Hydrogen Gas Inhalation Alleviates Radiation-Induced Bone Marrow Damage in Cancer Patients

Abstract:

Abstract: Background:

Radiotherapy for cancer patients is one of the useful methods; however, it not only impairs the targeted tumor tissues but also damage the normal surrounding tissues. Intensity modulated radiation therapy (IMRT) for cancer patients has been recently performed to alleviate the adverse effects, but reducing bone marrow damage is limited in the patients with multiple tumor lesions and large irradiation volume. Molecular hydrogen (H2) was recently reported as a preventive and therapeutic antioxidant that selectively scavenges hydroxy radical (*OH) and peroxynitrite (ONOO-). This observational study aims to examine whether H2 gas treatment improves IMRT radiation-induced bone marrow damage in cancer patients. Methods:

The patients with end stage of cancer were received IMRT once per day for 1 to 4 weeks except Saturday and Sunday. After each IMRT, the patients of control group (n = 7) were housed in health care chamber (HCC, mild hyperbaric oxygen chamber) for 30 minutes, and the patients of H2 group (n = 16) were also housed in HCC and received 5% H2 gas for 30 minutes once per day. Radiation-induced bone marrow damage was evaluated by hematological examination of peripheral blood obtained before and after IMRT. Results:

IMRT with HCC therapy significantly reduced white blood cells (WBC) and platelets (PLT) respectively, but not red blood cells (RBC), hemoglobin (HGB) and hematocrit (HT). In contrast, H2 gas treatment significantly alleviates reducing effects of WBC and PLT respectively. There was no difference in anti-tumor effects between the two groups. Interpretation: Our study demonstrated that H2 gas inhalation therapy significantly alleviates IMRT radiation-induced bone marrow damage without compromising anti-tumor effects. These results suggest that H2 gas treatment would be a strategy for reducing IMRT bone marrow damage in cancer patients.