The objectives of this paper were to determine the level of oxidative stress in atrophied gastrocnemius, and to verify the effect of molecular hydrogen (H2) saturated alkaline electrolyzed water (HSW) on gastrocnemius atrophy by modifying the redox status, indicated by 8-hydroxy-2′-deoxyguanosine (8-OHdG), malondialdehyde (MDA), and superoxide dismutase (SOD)-like activity. Female Wistar rats were divided into four groups: (1) the control (CONT); (2) the Hindlimb unloading (HU, for 3 weeks) given purified normal water (HU-NW); (3) the HU given alkaline electrolyzed reduced water (HU-AEW); and (4) the HU given HSW (HU-HSW). We showed that 8-OHdG, but not MDA, significantly increased by 149% and 145% in HU-NW and HU-AEW, respectively, when compared with CONT. In contrast, there was a trend toward suppression in 8-OHdG levels (increased by 95% compared with CONT) by treatment of HSW, though this effect was not prominent. Additionally, SOD-like activity significantly increased in both HU-NW (184%) and HU-AEW (199%) when compared with CONT. This result suggests the elevation of O2-· in the atrophied gastrocnemius. However, upregulation of SOD-like activity in the HU-HSW was increased by only 169% compared with CONT, though this difference is too small to detect statistical significance. HU led to 13% and 15% reduction of gastrocnemius wet weights in HU-NW and HU-AEW, respectively, compared with CONT. And the reduction of gastrocnemius wet weights in HU-HSW was attenuated by 7% compared with CONT. The gastrocnemius wet weights in the HU-HSW group were significantly greater than those in the HU-AEW, but not statistically significant with HU-NW. These results indicate that HU causes an increase in oxidative stress, but, in this experimental protocol, continuous consumption of HSW during HU does not demonstrate successful attenuation of oxidative stress and HU-mediated gastrocnemius atrophy.
Hydrogen has been reported to relieve damage in many disease models, and is a potential additive in drinking water to provide protective effects for patients as several clinical studies revealed. However, the absence of a dose-response relationship in the application of hydrogen is puzzling. We attempted to identify the dose-response relationship of hydrogen in alkaline electrolyzed drinking water through the aspirin induced gastric injury model. In this study, hydrogen-rich alkaline water was obtained by adding H2 to electrolyzed water at one atmosphere pressure. After 2 weeks of drinking, we detected the gastric mucosal damage together with MPO, MDA and 8-OHdG in rat aspirin induced gastric injury model. Hydrogen-dose dependent inhibition was observed in stomach mucosal. Under pH 8.5, 0.07, 0.22 and 0.84 ppm hydrogen exhibited a high correlation with inhibitory effects showed by erosion area, MPO activity and MDA content in the stomach. Gastric histology also demonstrated the inhibition of damage by hydrogen-rich alkaline water. However, 8-OHdG level in serum did not have significant hydrogen-dose dependent effect. pH 9.5 showed higher but not significant inhibitory response compared with pH 8.5. Hydrogen is effective in relieving the gastric injury induced by aspirin-HCl, and the inhibitory effect is dose-dependent. The reason behind this may be that hydrogen-rich water directly interacted with the target tissue, while the hydrogen concentration in blood was buffered by liver glycogen, evoking a suppressed dose-response effect. Drinking hydrogen-rich water may protect healthy individuals from gastric damage caused by oxidative stress.
In Japan, alkaline electrolyzed water (AEW) apparatus have been approved as a medical device. And for the patients with gastrointestinal symptoms, drinking AEW has been found to be effective in relieving gastrointestinal symptoms. But some users of AEW apparatus do not have abdominal indefinite complaint. Little attention has been given to the benefit for the users which have no abdominal indefinite complaint. The object of this study is to evaluate the effect on health, including gastrointestinal symptoms, when a person without abdominal indefinite complaint, etc., drinks AEW on a daily basis. A double-blind, randomized controlled trial has been designed. Four-week period of everyday water drinking, PW drinking group: drink purified tap water as a placebo, AEW drinking group: drink alkaline electrolyzed water which made by electrolysis of purified tap water. Before the experiment and after the 4-week period of water drinking, Blood tests, physical fitness evaluations, and questionnaire evaluations is conducted. In this study, we did not specifically select patients with gastrointestinal symptoms. Sufficiently clear effect could not be confirmed. But the stools were more normal, and, as shown in the previous report, that drinking AEW is considered to contribute to intestinal normalization. In addition, when drinking AEW, a high proportion of the respondents said that they felt they were able to sleep soundly, and the proportion of subjects who answered that they felt good when awakening increased. The effect of reducing oxidative stress, thus allowing for improved sleep, was exhibited by drinking AEW containing hydrogen, which is considered to be an antioxidant substance. This research were approved by the Ethics Committee of the Osaka City University Graduate School of Medicine (No. 837) and were registered in the University Hospital Medical Information Network (UMIN) Clinical Trials Registry (UMIN ID: UMIN000031800) on March 22, 2018.