First Author | Kim H | Year | 2020 |
Journal | Brain Behav Immun | Volume | 87 |
Pages | 765-776 | PubMed ID | 32201254 |
Mgi Jnum | J:309298 | Mgi Id | MGI:6717585 |
Doi | 10.1016/j.bbi.2020.03.011 | Citation | Kim H, et al. (2020) AIM2 inflammasome contributes to brain injury and chronic post-stroke cognitive impairment in mice. Brain Behav Immun 87:765-776 |
abstractText | Although over one-third of stroke patients may develop post-stroke cognitive impairment (PSCI), the mechanisms underlying PSCI remain unclear. We explored here, the involvement of post-stroke inflammasomes in long-term PSCI development, using a 45 min-middle cerebral artery occlusion (MCAO)/reperfusion-induced PSCI model. Immunohistological assessment on day 1, 3, and 7 was followed by cognitive function test 28 days post-stroke. Evaluation of inflammasome sensor gene expression in aged mouse brains showed dominant expression of absent in melanoma 2 (Aim2) in 6-, 12-, and 18-month-old mouse brains. AIM2 mRNA and protein increased until 7 days post-stroke. PSCI decreased anxiety in elevated plus maze test and impaired spatial learning and memory functions in Morris water maze test 28 days post-stroke. AIM2 and other inflammasome subunit immunoreactivities, including those for caspase-1, interleukin (IL)-1beta, and IL-18, were higher in the hippocampus and cortex of the PSCI than in those of the sham group 7 days post-stroke. AIM2 immunoreactivity of the PSCI group was primarily co-localized with Iba-1 (microglial marker) and CD31 (endothelial cell marker) immunoreactivities but not NeuN (neuronal marker) and GFAP (astrocyte marker) immunoreactivities, suggesting that microglia or endothelial cell-induced AIM2 production mediated PSCI pathogenesis. Additionally, inflammasome-induced pyroptosis might contribute to acute and chronic neuronal death after stroke. AIM2 knockout (KO) and Ac-YVAD-CMK-induced caspase-1 inhibition in mice significantly improved cognitive function and reversed brain volume in the hippocampus relative to those in stroke mice. Conclusively, AIM2 inflammasome-mediated inflammation and pyroptosis likely aggravated PSCI; therefore, targeting and controlling AIM2 inflammasome could potentially treat PSCI. |