The protective effect of 2-(2-benzonfu-ranyl)-2-imidazoline against oxygen-glucose deprivation in cultured rat cortical astrocytes

Combined Treatment With 2-(2-Benzofu-Ranyl)-2-Imidazoline and Recombinant Tissue Plasminogen Activator Protects Blood-Brain Barrier Integrity in a Rat Model of Embolic Middle Cerebral Artery Occlusion

Recombinant tissue plasminogen activator (rt-PA) is used to treat acute ischemic stroke but is only effective if administered within 4.5 h after stroke onset. Delayed rt-PA treatment causes blood-brain barrier (BBB) disruption and hemorrhagic transformation. The compound 2-(-2-benzofuranyl)-2-imidazoline (2-BFI), a newly discovered antagonist of high-affinity postsynaptic N-methyl-D-aspartate (NMDA) receptors, has been shown to have neuroprotective effects in ischemia. Here, we investigated whether combining 2-BFI and rt-PA can ameliorate BBB disruption and prolong the therapeutic window in a rat model of embolic middle cerebral artery occlusion (eMCAO). Ischemia was induced in male Sprague Dawley rats by eMCAO, after which they were treated with 2-BFI (3 mg/kg) at 0.5 h in combination with rt-PA (10 mg/kg) at 6 or 8 h. Control rats were treated with saline or 2-BFI or rt-PA. Combined therapy with 2-BFI and rt-PA (6 h) reduced the infarct volume, denatured cell index, BBB permeability, and brain edema. This was associated with increased expression of aquaporin 4 (AQP4) and tight junction proteins (occludin and ZO-1) and downregulation of intercellular adhesion molecule 1 (ICAM-1) and matrix metalloproteinases 2 and 9 (MMP2 and MMP9). We conclude that 2-BFI protects the BBB from damage caused by delayed rt-PA treatment in ischemia. 2-BFI may therefore extend the therapeutic window up to 6 h after stroke onset in rats and may be a promising therapeutic strategy for humans. However, mechanisms to explain the effects oberved in the present study are not yet elucidated.

2-BFI Provides Neuroprotection Against Inflammation and Necroptosis in a Rat Model of Traumatic Brain Injury

Inflammation and programmed necrosis (necroptosis) are the two hallmark pathological changes after traumatic brain injury (TBI) that contribute to aggravated brain damage. 2-(2-Benzofuranyl)-2-imidazoline (2-BFI) has been shown to exert both anti-inflammatory and programmed cell death effects. Therefore, the aim of the present study was to evaluate the potential beneficial effects of 2-BFI in a rat model of TBI induced by a weight-drop device. 2-BFI or vehicle was given via intraperitoneal injection starting at 30 min post trauma and then twice daily for three consecutive days. Following a neurofunctional test at 72 h after injury, histological, molecular, and immunohistochemistry analyses were performed on the pericontusional areas of the brain. 2-BFI treatment significantly attenuated neurological deficits, brain edema and blood-brain barrier permeability after TBI. Also, treatment with 2-BFI significantly reduced microglial activation, neutrophil infiltration, and proinflammatory cytokine interleukin (IL)-1β secretion, which is related to nucleotide binding and oligomerization domain-like receptor family pyrin domain-containing 3 (NLRP3) inflammasome activation after TBI. In addition, 2-BFI treatment markedly reduced cortical tissue loss as well as repressed TBI-induced increases in necroptosis and necroptosis-associated proteins, including receptor-interacting protein (RIP1), RIP3, and mixed linkage kinase domain-like (MLKL) in the pericontusional brain tissue. Taken together, these findings indicate that 2-BFI may be an effective neuroprotectant after brain trauma and warrants further study.