Effect of Ultramicro Superparamagnetic Iron Oxide Nanoparticles on Cerebral Infarction in Mice.

ABSTRACT

To investigate the effect of Feraheme (ferumoxytol) intravenous injection on cerebral infarction volume and inflammatory response in mice with permanent middle cerebral artery occlusion. We randomly divided 30 CS7BL6J mice into sham operated group, normal saline control group, and Feraheme group with 10 mice in each group. The model of permanent occlusion of right middle cerebral artery was made via the modified suture method in the normal saline control group and the Feraheme group. After 24 h of establishment the model, the tail vein was injected with 18 mg/kg Feraheme in the sham operation group and Feraheme group, and the normal saline control group was injected with an equal volume of normal saline. Neurobehavioral scores were obtained 24 h (before injection of Feraheme or normal saline) and 48 h (before MRI) after the model was established. The volume of cerebral infarction was calculated according to T2 weighted imaging. Orbital blood was collected after nodal scanning to detect serum TNF-α, IL-1ß, and IL-6 levels. Then, the brain tissues of mice were killed for HE staining and IBAL immunohistochemical staining. No significant differences in cerebral infarction volume and neurological function were observed between the normal saline control group and Feraheme group. The levels of TNF-α, IL-1ß and IL-6 in the normal saline control group and Feraheme group were significantly higher than those in the sham operation group (P < 0.05), but there were no significant differences between the normal saline control group and Feraheme group. We showed that intravenous injection of 18 mg/kg Feraheme 24 h after cerebral ischemia does not affect the infarct volume and inflammatory response, suggesting that the dose of Feraheme can be used for molecular imaging studies of inflammatory response after cerebral ischemia.