International journal of molecular medicine
-
Intestinal ischemia/reperfusion (I/R) injury is a serious condition in intensive care patients, resulting in severe inflammation and remote organ damage. The activation of the mammalian target of rapamycin (mTOR)/p70 ribosomal S6 kinase (p70S6K) signaling pathway exerts protective effect against ischemia/reperfusion injury. Ghrelin, an orexigenic hormone, inhibits the release of pro-inflammatory cytokines, such as interleukin (IL)-1β, tumor necrosis factor-α and IL-6. ⋯ To determine whether the beneficial effects of ghrelin following gut I/R injury are associated with the mTOR/p70S6K signaling pathway, the phosphorylation levels of mTOR and p70S6K were detected by western blot analysis. Our results revealed that mTOR and p70S6K phosphorylation increased in the tissue from the small intestine and pulmonary tissue in the animals treated with ghrelin. These findings suggest that ghrelin attenuates organ injury following gut I/R by promoting the activation of the mTOR/p70S6K signaling pathway.
-
The enhancement of endogenous neurogenesis has been suggested in the treatment of traumatic brain injury (TBI); however, the factors that trigger the process of adult neurogenesis following TBI remain elusive. In the adult mammalian central nervous system, there are 2 neurogenic regions: the subgranular zone (SGZ) of the hippocampus and the subventricular zone (SVZ) of the lateral ventricles, both of which maintain relatively quiescent states in a stable microenvironment. However, once stimulated by intrinsic and extrinsic events, relevant signals are activated in these 2 regions. ⋯ In addition, the number of survivin (+) cells, as well as that of BrdU (+) cells increased in the SGZ of the dentate gyrus (DG) in the hippocampus following TBI, as shown by immunofluorescence double staining; the co-localization of survivin and BrdU was shown in the merged images. The expression of survivin was also significantly increased in the doublecortin (DCX) (+) immature neurons in the DG of the hippocampus soon after the induction of TBI. Taken together, these data confirm the connection between the expression of survivin and adult neurogenesis following TBI; our data also suggest the therapeutic potential of upregulating survivin expression as a novel strategy for the effective treatment of TBI.
-
The inhalation anesthetic, isoflurane, induces learning and memory impairment. Mitochondrial dysfunction and oxidative stress are thought to play important roles in isoflurane-induced neuroapoptosis. In this study, we treated neuronal cells with isoflurane for 6 h. ⋯ Our findings demonstrated that the neuroprotective effects of RESV were independent on its direct radical scavenging properties. Following treatment of the cells with various concentrations of RESV, we found that RESV induced the expression of mitochondrial superoxide dismutase and catalase activity, and reduced mitochondrial oxidative stress and damage. The data from the present study demonstrate that RESV effectively protects neuronal cells from isoflurane-induced cytotoxicity by activating the Akt signaling pathway.