Methane Attenuates Hepatic Ischemia/Reperfusion Injury in Rats Through Antiapoptotic, Anti-Inflammatory, and Antioxidative Actions

ABSTRACTHepatic ischemia/reperfusion (I/R) injury, which occurs in various diseases, introduces severe tissue damage and liver dysfunction. However, no promising therapies for such a significant condition currently exist. Methane has been suggested to exert a protective effect against intestinal I/R injury. In this study, we introduced methane to treat hepatic I/R injury to show its promising protective effect. Also, intraperitoneal injection with methane-rich saline, which could have potential clinical applications, was applied as a new method. Partial liver warm ischemia was applied in Sprague-Dawley rats for 60 min followed by succedent reperfusion. In the test for effective dosage, methane-rich saline was administrated intraperitoneally to the rats at doses of 1, 5, 20, or 40 mL/kg at onset of reperfusion. In the test for protective effect, rats received methane-rich saline intraperitoneally at a dose of 10 mL/kg before the initiation of reperfusion. We found that methane-rich saline significantly decreased serum alanine aminotransferase, aspartate aminotransferase activity, and the occurrence of necrosis. Moreover, methane-rich saline reduced the amount of caspase-3 and the number of apoptotic cells. In addition, methane-rich saline increased the level of superoxide dismutase and decreased the level of malondialdehyde and 8-hydroxyguanosine. Furthermore, research indicated that methane-rich saline markedly decreased gene expression and content of tumor necrosis factor-α and interleukin-6. Also, reduced CD68-positive cells showed decreased inflammatory cells in the liver. Our results suggest that methane protects the liver against I/R injury through antiapoptotic, antioxidative, and anti-inflammatory actions.