机构:[1]Institute of Hypoxia Medicine, Xuanwu hospital, Capital Medical University, Beijing 100053, China首都医科大学宣武医院[2]Department of China-America Institute of Neuroscience , Xuanwu Hospital, Capital Medical University, Beijing 100053, China中美神经科学研究所首都医科大学宣武医院[3]Cerebrovascular Diseases Research Institute, Xuanwu Hospital, Capital Medical University, Beijing, China首都医科大学?脑血管病研究所首都医科大学宣武医院[4]Center for Neuroscience Discovery, Institute for Healthy Aging, University of North Texas Health Science Center at Fort Worth, Texas 76107, USA[5]Emergency department, Xuanwu hospital, Capital Medical University, Beijing 100053, China急诊科首都医科大学宣武医院[6]Beijing Key Laboratory of Hypoxia Translational Medicine, Beijing 100053, China
Limb Remote ischemic conditioning (LRIC) has been proved to be a promising neuroprotective method in white matter lesions after ischemia; however, its mechanism underlying protection after chronic cerebral hypoperfusion remains largely unknown. Here, we investigated whether LRIC promoted myelin growth by activating PI3K/Akt/mTOR signal pathway in a rat chronic hypoperfusion model. Thirty adult male Sprague Dawley underwent permanent double carotid artery (2VO), and limb remote ischemic conditioning was applied for 3 days after the 2VO surgery. Cognitive function, oligodendrocyte counts, myelin density, apoptosis and proliferation activity, as well as PTEN/Akt/mTOR signaling activity were determined 4 weeks after treatment. We found that LRIC significantly inhibited oligodendrocytes apoptosis (p< 0.05), promoted myelination (p< 0.01) in the corpus callosum and improved spatial learning impairment (p< 0.05) at 4 weeks after chronic cerebral hypoperfusion. Oligodendrocytes proliferation, along with demyelination, in corpus callosum were not obviously affected by LRIC (p> 0.05). Western blot analysis indicated that LRIC upregulated PTEN/Akt/mTOR signaling activities in corpus callosum (p< 0.05). Our results suggest that LRIC exerts neuroprotective effect on white matter injuries through activating PTEN/Akt/mTOR signaling pathway after chronic cerebral hypoperfusion.
基金:
National Natural Science Foundation of China (81573867),
Distinguished Professor of Cheung Kong Scholars Program (T2014251),
National Science Foundation for Distinguished Young Scholars (81325007)
Scientific Special Funding of Capital Health Development (NO. 2011-1001-03).