Astragaloside Ⅳ suppresses post-ischemic natural killer cell infiltration and activation in the brain:involvement of histone deacetylase inhibition  

作　　者：Baokai Dou Shichun Li Luyao Wei Lixin Wang Shiguo Zhu Zhengtao Wang Zunji Ke Kaixian Chen Zhifei Wang 

机构地区：[1]School of Basic Medical Sciences,Shanghai University of Traditional Chinese Medicine,Shanghai 201203,China [2]Institute of Chinese Materia Medica,Shanghai University of Traditional Chinese Medicine,Shanghai 201203,China [3]Academy of Integrative Medicine,Shanghai University of Traditional Chinese Medicine,Shanghai 201203,China

出　　处：《Frontiers of Medicine》2021年第1期79-90,共12页医学前沿（英文版）

基　　金：supported by the National Natural Science Foundation of China(Nos.81503055 and 81873029);Shanghai Youth Eastern Scholar(No.QD2015037).

摘　　要：Natural killer(NK)cells,a type of cytotoxic lymphocytes,can infiltrate into ischemic brain and exacerbate neuronal cell death.Astragaloside Ⅳ(ASIV)is the major bioactive ingredient of Astragalus membranaceus,a Chinese herbal medicine,and possesses potent immunomodulatory and neuroprotective properties.This study investigated the effects of ASIV on post-ischemic brain infiltration and activation of NK cells.ASIV reduced brain infarction and alleviated functional deficits in MCAO rats,and these beneficial effects persisted for at least 7 days.Abundant NK cells infiltrated into the ischemic hemisphere on day 1 after brain ischemia,and this infiltration was suppressed by ASIV.Strikingly,ASIV reversed NK cell deficiency in the spleen and blood after brain ischemia.ASIV inhibited astrocyte-derived CCL2 upregulation and reduced CCR2+NK cell levels in the ischemic brain.Meanwhile,ASIV attenuated NK cell activating receptor NKG2D levels and reduced interferon-γproduction.ASIV restored acetylation of histone H3 and the p65 subunit of nuclear factor-κB in the ischemic brain,suggesting inhibition of histone deacetylase(HDAC).Simultaneously,ASIV prevented p65 nuclear translocation.The effects of ASIV on reducing CCL2 production,restoring acetylated p65 levels and preventing p65 nuclear translocation were mimicked by valproate,an HDAC inhibitor,in astrocytes subjected to oxygen-glucose deprivation.Our findings suggest that ASIV inhibits post-ischemic NK cell brain infiltration and activation and reverses NK cell deficiency in the periphery,which together contribute to the beneficial effects of ASIV against brain ischemia.Furthermore,ASIV’s effects on suppressing NK cell brain infiltration and activation may involve HDAC inhibition.

关 键 词：astragalosideⅣ brain ischemia natural killer cells histone deacetylase nuclear factor-κB 

分 类 号：R743.31[医药卫生—神经病学与精神病学]