Protective effect of hydrogen (H₂) gas on cardiac ischemia-reperfusion (I/R) injury has been demonstrated previously. This study was designed to test the hypothesis that hydrogen-rich saline (saline saturated with molecular hydrogen), which is easy to use, induces cardioprotection against ischemia (30 min) and reperfusion (24 h) injury in rats. Adult male Sprague-Dawley rats underwent 30-min occlusion of the left anterior descending (LAD) coronary artery and 24-h reperfusion. Intraperitoneal injection of hydrogen-rich saline before reperfusion significantly decreased plasma and myocardium malondialdehyde (MDA) concentration, decreased cardiac cell apoptosis, and myocardial 8-hydroxydeoxyguanosine (8-OHdG) in area at risk zones (AAR), suppressed the activity of caspase-3, and reduced infarct size. The heart function parameters including left ventricular systolic pressure (LVSP), left ventricular diastolic pressure (LVDP), +(dP/dt)_max and −(dP/dt)_max were also significantly improved 24 h after reperfusion. It is concluded that hydrogen-rich saline is a novel, simple, safe, and effective method to attenuate myocardial I/R injury.

Objective: We investigated the feasibility and efficacy of hydrogen-rich saline therapy on delayed neurologic sequelae in a rat model of severe acute carbon monoxide (CO) poisoning. Design: Controlled animal study. Setting: University research laboratory for Diving Medicine. Subjects: Sprague-Dawley rats weighing 250 ± 20 g. Interventions: The rats were exposed to 1000 ppm CO in air for 40 min and then to 3000 ppm for another 20 min until they lost consciousness. Rats were intraperitoneal injected with hydrogen-rich saline or normal saline (10 mL/kg) for six times after resuscitation at 0, 12, 24, 36, 48, and 60 hrs, respectively. The rats without CO poisoning were used as normal controls. Measurements and Main Results: Brain tissue inflammation, cell death, and cognitive dysfunction were observed at one week after CO poisoning. Hydrogen-rich saline treatment significantly reduced the level of degraded myelin basic protein, decreased the expression of ionized calcium-binding adapter molecule 1, Iba1, a microglial marker, reduced DNA oxidation, and suppressed proinflammatory cytokine interleukin-1β, interleukin-6, and tumor necrosis factor-α in the cortex and hippocampal tissues when compared with those in normal saline-treated rats. These histologic and biological improvements were accompanied with an improvement in the Morris water maze test. Conclusions: This observation demonstrated that hydrogen-rich saline peritoneal injection improves histologic and functional assessment in a rat model of CO encephalopathy. Hydrogen saline has potentials as a novel and alternative therapy for severely CO-poisoned patients with delayed neurologic sequelae. The therapeutic effects of hydrogen-rich saline may be related to antioxidant and anti-inflammatory actions.

Arterialized vein grafts often fail due to intimal hyperplasia. Hydrogen potently protects organs and cells from many insults via its anti-inflammatory and antioxidant properties. We investigated the efficacy of oral administration of hydrogen-rich water (HW) for prevention of intimal hyperplasia. The inferior vena cava was excised, stored in cold Ringer solution for 2 h, and placed as an interposition graft in the abdominal aorta of syngeneic Lewis rats. HW was generated by immersing a magnesium stick in tap water (Mg + 2H₂O → Mg (OH)₂ + H₂). Beginning on the day of graft implantation, recipients were given tap water [regular water (RW)], HW or HW that had been subsequently degassed water (DW). Six weeks after grafting, the grafts in the rats given RW or DW had developed intimal hyperplasia, accompanied by increased oxidative injury. HW significantly suppressed intimal hyperplasia. One week after grafting, the grafts in HW-treated rats exhibited improved endothelial integrity with less platelet and white blood cell aggregation. Up-regulation of the mRNAs for intracellular adhesion molecules was attenuated in the vein grafts of the rats receiving HW. Activation of p38 mitogen-activated protein kinase, matrix metalloproteinase (MMP)-2, and MMP-9 was also significantly inhibited in grafts receiving HW. In rat smooth muscle cell (A7r5) cultures, hydrogen treatment for 24 h reduced smooth muscle cell migration. Drinking HW significantly reduced neointima formation after vein grafting in rats. Drinking HW may have therapeutic value as a novel therapy for intimal hyperplasia and could easily be incorporated into daily life.