thiourea and Subarachnoid-Hemorrhage

Perfusion abnormalities due to vasospasm remain a major cause of morbidity and mortality in subarachnoid hemorrhage (SAH). Despite a large number of clinical trials, therapeutic options with strong evidence for prevention and treatment of cerebral vasospasm are rare. In this study, we aimed to evaluate the neuroprotective effect of salubrinal (SLB) in endoplasmic reticulum stress-induced apoptosis, a catastrophic consequence of vasospasm.. Thirty-two Wistar albino rats were divided into 4 groups of 8 rats each: control group, SAH, SAH+SLB, and SAH+nimodipine (NMN). In the SAH+SLB group, intraperitoneal SLB (1 mg/kg dose) administered 30 minutes after establishment of SAH, and in the SAH+NMN group, intraperitoneal NMN (0.1 mg/kg dose) was also administered 30 minutes after SAH.. Higher total antioxidant status level, lower oxidative stress index, and significantly higher vascular endothelial growth factor-A (VEGF-A) level were detected in the SAH+SLB and SAH+NMN groups compared with the SAH group. There was a significant increase in eukaryotic translation initiation factor-2 alpha (elF2α) level in the SAH+SLB group compared with the SAH group. Histopathological evaluation revealed decrease in the subarachnoid hemorrhagic area, as well as in cortical edema and apoptotic bodies in the SAH+SLB and SAH+NMN groups. There was a significant decrease in caspase-3 staining in the SAH+SLB group, and the levels were significantly less in the SAH+NMN group than the SAH and SAH+SLB groups.. SLB, selective inhibitor of eIF2α dephosphorylation, and NMN, a calcium channel blocker, can ameliorate SAH-induced damage. Inhibition of eIF2α dephosphorylation and enhanced VEGF-A production with SLB may protect brain tissue from apoptosis.

Topics: Animals; Cinnamates; Disease Models, Animal; Endoplasmic Reticulum Stress; Neuroprotective Agents; Oxidative Stress; Rats; Rats, Wistar; Subarachnoid Hemorrhage; Thiourea; Vasospasm, Intracranial

Oxidative stress and neuronal apoptosis are considered crucial therapeutic targets against early brain injury (EBI) after subarachnoid hemorrhage (SAH). Emerging evidence indicates that mitochondrial dysfunction is the main reason for oxidative stress and neuronal apoptosis. MitoNEET, an outer mitochondrial membrane protein, has been shown to regulate mitochondrial function. However, whether mitoNEET activation attenuates oxidative stress and neuronal apoptosis after SAH remains unknown. This study was therefore conducted to verify the neuroprotective role of mitoNEET in EBI after SAH in rats. A total of 93 rats were subjected to an endovascular perforation model of SAH. TT01001, a selective agonist of mitoNEET, was administered intraperitoneally 1 h after SAH induction. Neurological tests, immunofluorescence, terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick-end labeling (TUNEL) staining, dihydroergotamine (DHE) staining, and western blot experiments were performed. The results showed that MitoNEET is expressed in neurons, but significantly decreased at 24 h after SAH induction. Activating mitoNEET with TT01001 significantly improved the neurological deficits, and reduced oxidative stress and neuronal apoptosis as measured by DHE and TUNEL staining, when compared with the SAH+vehicle group. Furthermore, TT01001 treatment decreased the expression of the proapoptotic marker, Bax, while increasing the expression of the antiapoptotic marker, Bcl-2. Together, our results suggested that mitoNEET activation with TT01001 reduced oxidative stress injury and neuronal apoptosis by improving mitochondrial dysfunction in EBI after SAH.

Topics: Animals; Apoptosis; Male; Mitochondria; Mitochondrial Proteins; Neurons; Neuroprotection; Neuroprotective Agents; Oxidative Stress; Piperidines; Rats; Rats, Sprague-Dawley; Subarachnoid Hemorrhage; Thiourea