Estimation of the hydrogen concentration in rat tissue using an airtight tube following the administration of hydrogen via various routes

Hydrogen exerts beneficial effects in disease animal models of ischemia-reperfusion injury as well as inflammatory and neurological disease. Additionally, molecular hydrogen is useful for various novel medical and therapeutic applications in the clinical setting. In the present study, the hydrogen concentration in rat blood and tissue was estimated. Wistar rats were orally administered hydrogen super-rich water (HSRW), intraperitoneal and intravenous administration of hydrogen super-rich saline (HSRS), and inhalation of hydrogen gas. A new method for determining the hydrogen concentration was then applied using high-quality sensor gas chromatography, after which the specimen was prepared via tissue homogenization in airtight tubes. This method allowed for the sensitive and stable determination of the hydrogen concentration. The hydrogen concentration reached a peak at 5 minutes after oral and intraperitoneal administration, compared to 1 minute after intravenous administration. Following inhalation of hydrogen gas, the hydrogen concentration was found to be significantly increased at 30 minutes and maintained the same level thereafter. These results demonstrate that accurately determining the hydrogen concentration in rat blood and organ tissue is very useful and important for the application of various novel medical and therapeutic therapies using molecular hydrogen.

Luminal Injection of Hydrogen-Rich Solution Attenuates Intestinal Ischemia-Reperfusion Injury in Rats

Luminal preservation of the intestine is an attractive method to locally mitigate preservation injury and ischemic-reperfusion injury in small bowel transplantation (SBT) because this method has a potential to maintain the intestinal graft integrity. Hydrogen is noted as an antioxidant material by reducing hydroxyl radicals. We hypothesized that hydrogen-containing solution can be an optimum material for luminal preservation method in SBT. Ischemic reperfusion was induced in Lewis rats by occlusion of the supramesenteric artery and vein for 90 min. Experimental protocols were divided into four groups: sham operation group, no luminal injection (control) group, luminal injection of 5% glucose saline (GS) solution group, and luminal injection of hydrogen-rich GS (HRGS) group. Two milliliters of experimental solution was locally injected into the lumen of the intestine before declamping of vessels. Oxidative stress markers, proinflammatory cytokines, apoptosis in the crypt cells, and morphologic changes of the intestine were assessed. The production of malondialdehyde and 8-hydroxydeoxyguanosine, as oxidative stress markers, were markedly suppressed in HRGS group. The level of proinflammatory cytokines, such as inducible nitric oxide synthase and interleukin-6, was significantly inhibited in HRGS group. Crypt apoptosis was also significantly suppressed in HRGS group. Histopathologically, integrity of villus in intestine was maintained in HRGS group in comparison to the other groups. Luminal injection of hydrogen-rich solution can reduce oxidative stress and consequently ameliorate ischemic-reperfusion injury. Hydrogen-containing solution can be a novel and promising luminal preservation material in SBT.