Objective To investigate the effect of intravenous infusion of hyper-oxygenated solution (HOS) on small intestinal ischemia-reperfusion (I/R) injury in rabbits.Methods Twenty-four rabbits of both sexes,weighing 2.5-3.2 kg,were randomly divided into 3 groups ( n =8 each):sham operation group (group S),I/R group,and HOS group.Small intestinal I/R was produced by clamping the superior mesenteric artery (SMA) for 1 h followed by 2 h of reperfusion in I/R and HOS groups,while the SMA was only clamped in group S.HOS was infused intravenously at a rate of 20 ml· kg-1 ·h -1 via the auricular vein starting from the time immediately after clamping the SMA in group HOS and the equal volume of normal saline was infused instead of HOS in group I/R.Blood samples were obtained from the inferior vena cava at 2 h of reperfusion to detect the concentration of serum lactic acid.The animals were then sacrificed and the small intestine was removed for determination of the malondialdehyde (MDA) content,and activities of superoxide dismutase (SOD),catalase (CAT) and glutathione peroxidase (GSH-Px) in intestinal tissues and for microscopic examination.The pathological changes of the intestinal epithelia were observed and the damage.to the mucous membrane was scored.The internal organs were removed and bacterial translocation from gut to the internal organs was observed.Results Compared with group S,the level of MDA and lactic acid,and rate of bacterial translocation were significantly increased,and the activities of SOD,CAT and GSH-Px were significantly decreased in groups I/R and HOS ( P ＜ 0.05).Compared with group I/R,the level of MDA and lactic acid,rate of bacterial translocation,and activities of SOD,CAT and GSH-Px were significantly decreased in group HOS ( P ＜ 0.05).Conclusion Intravenous infusion of HOS can reduce small intestinal I/R injury in rabbits.

The well-known insulin-like growth factor 1 (IGF1)/IGF-1 receptor (IGF-1R) signaling pathway is overexpressed in many tumors, and is thus an attractive target for cancer treatment. However, results have often been disappointing due to crosstalk with other signals. Here, we report that IGF-1R signaling stimulates the growth of hepatocellular carcinoma (HCC) cells through the translocation of IGF-1R into the ER to enhance sarco-endoplasmic reticulum calcium ATPase 2 (SERCA2) activity. In response to ligand binding, IGF-1Rβ is translocated into the ER by β-arrestin2 (β-arr2). Mass spectrometry analysis identified SERCA2 as a target of ER IGF-1Rβ. SERCA2 activity is heavily dependent on the increase in ER IGF-1Rβ levels. ER IGF-1Rβ phosphorylates SERCA2 on Tyr⁹⁹⁰ to enhance its activity. Mutation of SERCA2-Tyr⁹⁹⁰ disrupted the interaction of ER IGF-1Rβ with SERCA2, and therefore ER IGF-1Rβ failed to promote SERCA2 activity. The enhancement of SERCA2 activity triggered Ca²⁺_ER perturbation, leading to an increase in autophagy. Thapsigargin blocked the interaction between SERCA2 and ER IGF-1Rβ and therefore SERCA2 activity, resulting in inhibition of HCC growth. In conclusion, the translocation of IGF-1R into the ER triggers Ca²⁺_ER perturbation by enhancing SERCA2 activity through phosphorylating Tyr⁹⁹⁰ in HCC.