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31.
Yan Sun Chong-Chong Xu Jin Li Xi-Yin Guan Lu Gao Li-Xiang Ma Rui-Xi Li Yu-Wen Peng Guo-Pei Zhu 《PloS one》2013,8(2)
Demyelination contributes to the functional impairment of irradiation injured spinal cord. One potential therapeutic strategy involves replacing the myelin-forming cells. Here, we asked whether transplantation of Olig2+-GFP+-oligodendrocyte precursor cells (OPCs), which are derived from Olig2-GFP-mouse embryonic stem cells (mESCs), could enhance remyelination and functional recovery after spinal cord irradiation injury. We differentiated Olig2-GFP-mESCs into purified Olig2+-GFP+-OPCs and transplanted them into the rats’ cervical 4–5 dorsal spinal cord level at 4 months after irradiation injury. Eight weeks after transplantation, the Olig2+-GFP+-OPCs survived and integrated into the injured spinal cord. Immunofluorescence analysis showed that the grafted Olig2+-GFP+-OPCs primarily differentiated into adenomatous polyposis coli (APC+) oligodendrocytes (54.6±10.5%). The staining with luxol fast blue, hematoxylin & eosin (LFB/H&E) and electron microscopy demonstrated that the engrafted Olig2+-GFP+-OPCs attenuated the demyelination resulted from the irradiation. More importantly, the recovery of forelimb locomotor function was enhanced in animals receiving grafts of Olig2+-GFP+-OPCs. We concluded that OPC transplantation is a feasible therapy to repair the irradiated lesions in the central nervous system (CNS). 相似文献
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Sukehisa Nagano Margaret Takeda Lan Ma Betty Soliven 《Journal of neurochemistry》2001,77(6):1486-1495
Tumor necrosis factor-alpha and interferon-gamma are pleiotropic cytokines that regulate Schwann cell responses during injury and inflammatory demyelination. We have previously shown that cyclic AMP (cAMP)-elevating agents decrease the demyelination and Wallerian degeneration in experimental allergic neuritis. In this study, we examined the role of cAMP in cytokine-mediated signaling in a spontaneously immortal Schwann cell clone (iSC). We found that tumor necrosis factor-alpha and interferon-gamma exert synergistic inhibitory action on Schwann cell viability via the production of nitric oxide (NO) and ceramide (cer). Furthermore, we found that: (i) NO synthase inhibitors attenuate the cytokine-induced cer accumulation and cell death indicating that NO acts upstream of cer; and (ii) cytokine-induced cell death is decreased in iSCs pretreated continuously for 48-72 h with forskolin, an activator of adenylate cyclase. Although forskolin modulates the phosphorylation of ERKs and Akt, it decreases the susceptibility of iSC to cytokines via a separate mechanism operating after NO induction and before cer accumulation. We propose that the protective effect of cAMP-elevating agents in experimental allergic neuritis may be mediated in part via modulation of Schwann cell responses to cytokines. 相似文献
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A. H. Williams Ma Hta Kyu J. C. B. Fenton J. B. Cavanagh 《Journal of neurochemistry》1972,19(4):1073-1077
Abstract— Rats have been subjected to portocaval anastomosis and the ammonium ion in plasma and the glutamate and glutamine levels in plasma, red cells and brain have been estimated up to 6 weeks after operation. The glutamine, but not the glutamate, levels in brain were consistently raised, being about 2.5 times greater than normal and the level can be correlated with the level of plasma ammonium ion. Consideration is given to the possibility that the glutamine may be in the greatly enlarged neuroglial compartment in this abnormal metabolic state. 相似文献
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The suggested technique allows revealing the transport-specific dye (primulin) and catecholamine fluorescence simultaneously in the same cell of brain. Intense fluorescence is observed when brain tissue is quickly dehydrated and embedded in the epoxy resin. The same method is suggested for the identification of catecholamines in the embryonal and juvenile tissues of gastropod Lymnaea stagnalis (Mollusca Pulmonata) without using of primulin dye. 相似文献
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