Neuroprotective effect of apocynin nitrone in oxygen glucose deprivation-treated SH-SY5Y cells and rats with ischemic stroke

Purpose: To investigate the neuroprotective potential of apocynin nitrone (AN-1), a nitrone analogue of apocynin, in rat brain tissue as a novel candidate for ischemic stroke treatment.
Methods: In vitro neuroprotection of AN-1 was studied in SH-SY5Y cells treated with oxygen glucose deprivation (OGD). Cell viability was measured using 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2Htetrazolium bromide (MTT) assay, and intracellular reactive oxygen species (ROS) level was investigated using flow cytometry. The protection of AN-1 in cerebral ischemia-reperfusion (I/R) rats was evaluated by cerebral infarct area and neurological deficit score. Oxidative stress of the ischemic hemisphere was assessed by malondialdehyde (MDA), glutathione (GSH) and superoxide dismutase (SOD) levels.
Results: In OGD-treated SH-SY5Y cells, AN-1 reduced cell death and ROS level. In I/R rats, AN-1 exerted potential protection against neurological deficit by reducing infarction area, decreasing neurological deficit score and relieving oxidative stress. AN-1 exhibited stronger action than its parent compound apocynin in vitro, but the two had similar effects in vivo. In addition, AN-1 demonstrated efficacy close to or higher than the positive reference Edaravone® both in vitro and in vivo. Furthermore, AN-1 showed lower toxicity than apocynin in vitro.
Conclusion: The results suggest that AN-1 may be a potential neuroprotective agent for the treatment of ischemic stroke in human.

Keywords
Apocynin nitrone; Cerebral ischemia-reperfusion injury; Neuroprotection; eactive oxygen species; Oxidative stress