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

BACKGROUNDLuminal 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. METHODSIschemic reperfusion was induced in Lewis rats by occlusion of the supramesenteric artery and vein for 90 min. Experimental protocols were divided into four groupssham 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. RESULTSThe 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. CONCLUSIONLuminal 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.