[HTML][HTML] Activation of α-7 nicotinic acetylcholine receptor reduces ischemic stroke injury through reduction of pro-inflammatory macrophages and oxidative stress

Z Han, F Shen, Y He, V Degos, M Camus, M Maze… - PloS one, 2014 - journals.plos.org
Z Han, F Shen, Y He, V Degos, M Camus, M Maze, WL Young, H Su
PloS one, 2014journals.plos.org
Activation of α-7 nicotinic acetylcholine receptor (α-7 nAchR) has a neuro-protective effect
on ischemic and hemorrhagic stroke. However, the underlying mechanism is not completely
understood. We hypothesized that α-7 nAchR agonist protects brain injury after ischemic
stroke through reduction of pro-inflammatory macrophages (M1) and oxidative stress.
C57BL/6 mice were treated with PHA568487 (PHA, α-7 nAchR agonist), methyllycaconitine
(MLA, nAchR antagonist), or saline immediately and 24 hours after permanent occlusion of …
Activation of α-7 nicotinic acetylcholine receptor (α-7 nAchR) has a neuro-protective effect on ischemic and hemorrhagic stroke. However, the underlying mechanism is not completely understood. We hypothesized that α-7 nAchR agonist protects brain injury after ischemic stroke through reduction of pro-inflammatory macrophages (M1) and oxidative stress. C57BL/6 mice were treated with PHA568487 (PHA, α-7 nAchR agonist), methyllycaconitine (MLA, nAchR antagonist), or saline immediately and 24 hours after permanent occlusion of the distal middle cerebral artery (pMCAO). Behavior test, lesion volume, CD68+, M1 (CD11b+/Iba1+) and M2 (CD206/Iba1+) microglia/macrophages, and phosphorylated p65 component of NF-kB in microglia/macrophages were quantified using histological stained sections. The expression of M1 and M2 marker genes, anti-oxidant genes and nicotinamide adenine dinucleotide phosphate (NADPH) oxidase were quantified using real-time RT-PCR. Compared to the saline-treated mice, PHA mice had fewer behavior deficits 3 and 7 days after pMCAO, and smaller lesion volume, fewer CD68+ and M1 macrophages, and more M2 macrophages 3 and 14 days after pMCAO, whereas MLA's effects were mostly the opposite in several analyses. PHA increased anti-oxidant genes and NADPH oxidase expression associated with decreased phosphorylation of NF-kB p65 in microglia/macrophages. Thus, reduction of inflammatory response and oxidative stress play roles in α-7 nAchR neuro-protective effect.
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