A novel free radical scavenger, NSP-116, ameliorated the brain injury in both ischemic and hemorrhagic stroke models.

Reperfusion injury is a serious problem in ischemic stroke therapy, which leads to neuronal damage and intracranial hemorrhage (ICH). A novel free radical scavenger, NSP-116, has anti-oxidative effect and may ameliorate reperfusion injury. The purpose of this study was to investigate the effects of NSP-116 on both ischemic and hemorrhagic stroke models. First, we assessed whether NSP-116 has protective effects in vitro. Pre-treatment of NSP-116 decreased neuronal cell damage induced by H2O2 or LPS. Moreover, NSP-116 also suppressed mitochondria damage and apoptosis in H2O2-induced neuronal injury model. Based on these results, we used a middle cerebral artery occlusion (MCAO)-induced ischemic stroke model or a collagenase-induced ICH model. Using the MCAO model, we evaluated the cerebral blood flow (CBF), neurological deficit, and infarct volume. Hematoma volume was assessed at 3 days after ICH. In the MCAO model, oral administration of NSP-116 at 30 mg/kg attenuated the reduction of CBF, neurological deficits, and infarct formation. Interestingly, NSP-116 also ameliorated hematoma expansion and neurological deficits in the ICH model. Additionally, pre-treatment of NSP-116 suppressed the brain microvascular endothelial cell death induced by collagenase treatment. Collectively, our findings indicated that oral administration of NSP-116 attenuates both ischemic and hemorrhagic brain injuries after stroke.

Levetiracetam, an Antiepileptic Drug has Neuroprotective Effects on Intracranial Hemorrhage Injury.

Intracranial hemorrhage (ICH) is a devastating disease that induces hematoma formation with poor neuronal outcome. Levetiracetam (LEV) has been approval for epilepsy seizures. In a previous study, LEV exerted protective effects on cerebral ischemia models; however, the detail effects and the influence of LEV on ICH are still unknown. The aim of this study was to investigate whether oral administration of LEV (50 or 150 mg/kg) has protective effects on ICH injury using both in vivo and in vitro experiments. In in vivo experiments, we utilized ICH models induced by autologous blood (bICH) or collagenase (cICH) injection. Moreover, we established a neuronal injury model using SYSH5Y human neuroblastoma cell lines. In the bICH model, frequently oral administration of LEV attenuated both cerebral edema and neurological deficits. In addition, the expression levels of phosphorylation-extracellular signal­related kinase (ERK) 1/2 and cleaved caspase-7 were increased after ICH, and LEV suppressed such alterations. In in vitro experiments, hematoma releasing factors, such as hemoglobin (Hb) and hemin, induced neuronal cell death, and LEV treatment attenuated neuronal injury in a dose-dependent manner. In the cICH model, neurological deficits induced by extensive hematoma formation were attenuated by LEV without affecting hematoma volume. Taken together, these findings suggested that LEV has protective effect on neurons after ICH injury. Therefore, LEV may not only be an efficacious therapeutic agent for seizures, but also for post-hemorrhagic stroke brain injury.

Intracellular Fe2+ accumulation in endothelial cells and pericytes induces blood-brain barrier dysfunction in secondary brain injury after brain hemorrhage.

After intracranial hemorrhage (ICH), iron is released from the hematoma and induces secondary brain injury. However, the detail effect of iron on blood-brain barrier (BBB) function is still unknown. We investigated whether hemoglobin (Hb), ferrous ammonium sulfate (FAS) or hemin which contains iron have the detrimental effect on both human brain microvascular endothelial cells and pericytes by cellular function analysis in vitro. We developed an iron (Fe2+)-detectable probe, Si-RhoNox-1, to investigate intracellular Fe2+ accumulation (Fe2+intra). After FAS treatment, there was the correlation between Fe2+intra and cell death. Moreover, Hb or hemin treatment induced cell death, increased reactive oxygen species and promoted Fe2+intra in both cells. These changes were inhibited by the Fe2+ chelator, 2,2'-bipyridil (BP). Furthermore, hemin induced endothelial barrier dysfunction via disruption of junction integrity. Based on in vitro studies, we used a hemin-injection ICH mice model in vivo. Hemin injection (10 mM/10 µL, i.c.) induced deleterious effects including BBB hyper-permeability, neuronal deficits, neuronal damage, altered proteins expression, and Fe2+intra in BBB composed cells. Lastly, BP (40 mg/kg, i.p.) administration attenuated neuronal deficits at 3 days after surgery. Collectively, Hb or hemin damaged BBB composed cells via Fe2+intra. Therefore, the regulation of the Fe2+ movement in BBB might be effective for treatment of ICH.

Protective effects of the astaxanthin derivative, adonixanthin, on brain hemorrhagic injury.

Astaxanthin is beneficial for human health and is used as a dietary supplement. The present study was performed in order to examine the protective effects of the astaxanthin derivative, adonixanthin, against cell death caused by hemoglobin, collagenase, lipopolysaccharide, and hydrogen peroxide, which are associated with hemorrhagic brain injury. In an in vitro study, adonixanthin exerted cytoprotective effects against each type of damage, and its effects were stronger than those of astaxanthin. The increased production of reactive oxygen species in human brain endothelial cells in the hemoglobin treatment group was inhibited by adonixanthin. Moreover, adonixanthin suppressed cell death in SH-SY5Y cells. In an in vivo study, the oral administration of adonixanthin improved blood-brain barrier hyper-permeability in an autologous blood ICH model. We herein demonstrated for the first time that adonixanthin exerted protective effects against hemorrhagic brain damage by activating antioxidant defenses, and has potential as a protectant against intracerebral hemorrhage.