Angiotensin II Causes Apoptosis of Adult Hippocampal Neural Stem Cells and Memory Impairment Through the Action on AMPK-PGC1 alpha Signaling in Heart Failure

作者:Kim Min Seok; Lee Geun Hee; Kim Yong Min; Lee Byoung Wook; Nam Hae Yun; Sim U Cheol; Choo Suk Jung; Yu Seong Woon; Kim Jae Joong; Kwon Yunhee Kim*; Kim Seong Who*
来源:Stem Cells Translational Medicine, 2017, 6(6): 1491-1503.
DOI:10.1002/sctm.16-0382

摘要

Data are limited on the mechanisms underlying memory impairment in heart failure (HF). We hypothesized that angiotensin II (Ang II) may determine the fate of adult hippocampal neural stem cells (HCNs), a cause of memory impairment in HF. HCNs with neurogenesis potential were isolated and cultured from adult rat hippocampi. Ang II decreased HCN proliferation in dose- and timedependent manners. Moreover, Ang II treatment (1 mu M) for 48 hours induced apoptotic death, which was attenuated by pretreatment with Ang II receptor blockers (ARBs). Ang II increased mitochondrial reactive oxygen species (ROS) levels, which was related to mitochondrial morphological changes and functional impairment. Moreover, ROS activated the AMP-activated protein kinase (AMPK) and consequent peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC1 alpha) expression, causing cell apoptosis. In the HF rat model induced by left anterior descending artery ligation, ARB ameliorated the spatial memory ability which decreased 10 weeks after ischemia. In addition, neuronal cell death, especially of newly born mature neurons, was observed in HF rat hippocampi. ARB decreased cell death and promoted the survival of newly born neural precursor cells and mature neurons. In conclusion, Ang II caused HCN apoptosis through mitochondrial ROS formation and subsequent AMPK-PGC1 alpha signaling. ARB improved learning and memory behaviors impaired by neuronal cell death in the HF animal model. These findings suggest that HCN is one treatment target for memory impairment in HF and that ARBs have additional benefits in HF combined with memory impairment.

  • 出版日期2017-6