Subarachnoid Hemorrhage Group Research Articles

CDDO, an Anti-Inflammatory and Antioxidant Compound, Attenuates Vasospasm and Neuronal Cell Apoptosis in Rats Subjected to Experimental Subarachnoid Hemorrhage.

Subarachnoid hemorrhage (SAH) is a type of stroke caused by bleeding into the subarachnoid space. SAH is a medical emergency and requires prompt treatment to prevent complications such as seizures, stroke, or other brain damage. Treatment options may include surgery, medication, or a combination of both. 2-Cyano-3,12-dioxoolean-1,9-dien-28-oic acid (CDDO), a compound with anti-inflammatory and antioxidant properties, is currently being investigated as a potential treatment for various diseases, including chronic kidney disease and pulmonary arterial hypertension. In this study, the effects of CDDO on rats subjected to SAH were evaluated. Male Sprague-Dawley rats were divided into four groups (n = 6/group): (1) control group, (2) SAH group, (3) SAH + low-dose CDDO (10 mg/kg injected into the subarachnoid space at 24 h after SAH) group, and (4) SAH + high-dose CDDO (20 mg/kg) group. CDDO improved SAH-induced poor neurological outcomes and reduced vasospasm in the basal artery following SAH. It also decreased the SAH-induced expression of proinflammatory cytokines such as TNF-α, IL-1β, and IL-6 in both the cerebrospinal fluid and serum samples as determined by ELISA. A Western blot analysis confirmed an increase in the p-NF-κB protein level after SAH, but it was significantly decreased with CDDO intervention. Immunofluorescence staining highlighted the proliferation of microglia and astrocytes as well as apoptosis of the neuronal cells after SAH, and treatment with CDDO markedly reduced the proliferation of these glial cells and apoptosis of the neuronal cells. The early administration of CDDO after SAH may effectively mitigate neuronal apoptosis and vasospasm by suppressing inflammation.

β-hydroxybutyrate alleviates neurological deficits by restoring glymphatic and inflammation after subarachnoid hemorrhage in mice

BackgroundBoth glymphatic system dysfunction and inflammatory response aggravate neurological dysfunction after subarachnoid hemorrhage (SAH). Studies have shown that β-hydroxybutyrate (BHB) may mitigate painful diabetic neuropathy (PDN) by upregulating SNTA1 expression and reinstating AQP4 polarity. However, the potential of BHB to ameliorate glymphatic system function and inflammatory response in SAH mice remains uncertain. MethodsThe SAH models were constructed by injection of arterial blood into cisterna Magana. Three groups of C57 mice were randomly assigned: Sham, SAH, and BHB. All mice were subjected to neurological function assessment, western blot, immunofluorescence double staining, and RNA-seq. Glymphatic system function was examined with tracer and immunofluorescence double staining, and the differential genes were examined with RNA-seq. In addition, the expression of related inflammation was detected. ResultsCompared with the SAH group, BHB reinstated AQP4 polarization by upregulating SNTA1 protein to enhance the glymphatic system. According to RNA-seq, the different genes were primarily connected to microglia activation, astrocytes, and inflammation. Western blot and immunofluorescence further confirmed that the related inflammatory protein expression levels were upregulated. BHB attenuated neuroinflammation after SAH. Ultimately, it can mitigate the neurological deficits in SAH mice. ConclusionThe study reveals a novel mechanism that BHB treatment mitigates neurologic impairment in SAH mice. We propose that BHB may play a neuroprotective effect by enhancing glymphatic system function and attenuating neuroinflammatory subarachnoid hemorrhage.

Effect of Intrathecal Eugenol on Cerebral Vasospasm in an Experimental Subarachnoid Hemorrhage Model

Eugenol has various curative properties. It affects the dilatation of cerebral arteries by voltage-dependent Ca2+ channel inhibition. This study is the first to explore the impact of eugenol on neuroprotection and vasospasm in an experimental subarachnoid hemorrhage (SAH) model. Twenty-four adult male Sprague-Dawley rats were indiscriminately separated into 3 groups: the control group (n = 8), the SAH group (n = 8), and the eugenol group (n = 8). A double bleeding method was used. The eugenol group received intracisternal eugenol (Sigma-Aldrich, St. Louis, MO, USA) at 30μg/20μl after induction of SAH. On the 7th day, all groups were euthanized. Measurements were taken for basilar artery wall thickness, lumen diameter, serum endothelin-1, and caspase-3 levels. The eugenol group exhibited significantly lower wall thickness, endothelin-1, oxidative stress index, and caspase-3 levels compared to the SAH group. In comparison to the control group, the eugenol group showed a higher oxidative stress index along with higher endothelin-1, and caspase-3 levels, but these differences were not statistically significant. Wall thickness was significantly higher in the eugenol group than in the control group. This study represents the first literature exploration of intrathecal eugenol's impact on vasospasm induced after experimental SAH. Administration of intrathecal eugenol demonstrates a positive effect on treatment of experimental vasospasm, as well as on reduction of oxidative stress and apoptosis.

WITHDRAWN: Recombinant osteopontin stabilizes the blood brain barrier following subarachnoid hemorrhage in rats

Background and PurposeRecombinant osteopontin (rOPN) decreases neuronal cell death and brain edema and improves the neurological scores following subarachnoid hemorrhage (SAH) in rats. The molecular mechanisms of the preservation of blood-brain barrier of rOPN following SAH in rats were examined in this study. MethodsAdult rats were divided into 3 groups: sham, vehicle, and treatment groups. Each animal in the SAH group underwent a surgical procedure to induce SAH, and the brains was harvested at 24 hours for analysis. For the mechanism part of the study two additional groups were operated and treated with Fib-14 and Wortmannin additional to rOPN. rOPN was administered via the nasal route and neurological scores as well as brain water content were evaluated at 24 hours after SAH induction. The blood brain barrier (BBB) permeability was evaluated using Evans Blue dye extravasation. The expressions of tight junction proteins claudin-3, claudin-5, occludin and the phosphorylation of β-catenin were examined using Western blot analysis. ResultsrOPN improved neurological scores and reduced brain edema at 24 hours after SAH. The BBB preservation action of rOPN is mediated in part through stabilizing β-catenin and increasing expression of tight junction proteins, claudin-3, claudin-5, and occludin. rOPN is thought to exert its effects through FAK activated PI3K-Akt pathway. ConclusionSince BBB disruption is one of the major pathophysiology of EBI after SAH, rOPN may be a promising drug to maintain BBB integrity and functions in SAH treatment.

Intimal Hemorrhage of Basilar Artery Induced by Severe Vasospasm Following Subarachnoid Hemorrhage: The Experimental Analysis.

Cerebral vasospasm, a serious complication of subarachnoid hemorrhage (SAH), has been extensively studied for its neurochemical and pathophysiological mechanisms. However, the contribution of inner elastic membrane dissection and subintimal hemorrhage to basilar artery occlusion remains underexplored. This study investigates inner elastic membrane-related changes in the basilar artery after SAH. Twenty-four hybrid rabbits were divided into control, sham, and SAH groups, with SAH induced by autologous blood injection. After two weeks, basilar artery changes, vasospasm indexes (VSI), and dissections were evaluated. The SAH group showed significantly higher VSI, with vascular wall thickening, luminal narrowing, convoluted smooth muscle cells, intimal elastic membrane disruption, endothelial cell desquamation and apoptosis. Some SAH animals exhibited subintimal hemorrhage, inner elastic membrane dissection, and ruptures. Basilar arteries with subintimal hemorrhage had notably higher VSI. These findings highlight the role of subintimal hemorrhage and inner elastic membrane dissection in basilar artery occlusion post-SAH, offering valuable insights into vasospasm pathophysiology.

MiR-221-5p regulates blood–brain barrier dysfunction through the angiopoietin-1/-2/Tie-2 signaling axis after subarachnoid hemorrhage

ABSTRACT Aim To explore the potential role of microRNA miR-221-5p on the angiopoietin-1 (Ang-1)/Ang-2/Tie-2 signaling axis after subarachnoid hemorrhage (SAH) in a rat model. Methods Aspects of the rat’s behavior were measured using the Kaoutzanis scoring system to test neurological responses. This included feeding behavior, body contraction, motor, and eye-opening responses. Brain sections were studied using transmission electron microscopy and Evans blue extravasation. Levels of Ang-1, Ang-2, and Tie-2 were determined by Western blot, while miR-221-5p was quantified using stem-loop real-time quantitative PCR (RT-qPCR). Results The SAH group responded worse to the neurological response test than the sham-operated group. The intercellular space was widened in the SAH group, but not in the sham-operated group. Evans blue dye leaked significantly more into brain tissue cells of the SAH group. Stem-loop qRT-PCR showed elevated miR-221-5p levels. Additionally, Ang-1 and Tie-2 were reduced but Ang-2 expression was increased after SAH. This led to a significant reduction of the Ang-1/Ang-2 ratio in the brain tissue, which was associated with the destruction of the blood-brain barrier. Conclusion The data indicate that miR-221-5p might regulate blood-brain barrier dysfunction through the Ang-1/Ang-2/Tie-2 signaling axis, suggesting that it should be further investigated as a potential novel biomarker.

Abstract TP318: Evaluating Hypothalamic Injury in a Rat Model of Subarachnoid Hemorrhage

Background and purpose: Hypothalamus is one of the most affected parts of the brain by subarachnoid hemorrhage (SAH). There are some reports that hypothalamic disorders are important determinants of poor prognosis after SAH from acute to chronic phase. However, there have never been any reports on the development of therapeutic strategies targeting the hypothalamus for SAH, and few reports have even demonstrated immunohistological evidence of hypothalamic injury after SAH. Here, we demonstrated on the investigation of temporal changes in hypothalamic injury from the hyperacute phase to the chronic phase after SAH in a rat model of SAH. Methods: Moderate to severe endovascular perforation model of SAH was created using 300g - 450g Sprague-Dawley rats, and they were divided into two groups: Sham operated and SAH group.The endpoints were 3, 6, 12, 24, and 72 hours after SAH, and 7 days and 4 weeks after SAH, and physiological findings and neurological symptoms were measured and hypothalamic injury and related factors in the hypothalamus were studied immunohistochemically. Results: The SAH group showed significant neurological deterioration, and the expression of FJC, indicative of cell death, and TUNEL-positive cells, indicative of apoptosis, in the hypothalamus was significantly elevated in the early phase and decreased over time compared to the sham SAH group. On the other hand, oxytocin, a hypothalamic hormone associated with neuronal protection, was significantly decreased in the SAH group during the acute phase. Conclusions: The present study shows that hypothalamic injury appears hyper acute phase of SAH and persists at least during the acute phase of SAH. These findings suggest that the hypothalamus may be an important therapeutic target in the acute phase of SAH.

Abstract TP319: Time Course of Novel Hypothalamic Protein Sushi Repeat-Containing Protein X- Linked 2 Expression in a Rat Model of Subarachnoid Hemorrhage

Background: Hypothalamic injury after subarachnoid hemorrhage (SAH) is known to be associated with short- and long-term prognosis. Recently, a novel hypothalamic protein, Sushi repeat-containing protein X-linked 2 (SRPX2), was reported as a potential biomarker for hypothalamic damage after traumatic brain injury. However, there are no reports on SRPX2 in SAH, and its role is unknown. In this study, we investigated the expression of SRPX2 in the hypothalamus after SAH using a rat model of SAH. Methods: We made endovascular perforation model of SAH using 300g - 450g SD rats, and they were divided into two groups: Sham operated and SAH group. The endpoints were 3, 6, 12, 24, and 72 hours after SAH, and 7 days and 4 weeks after SAH, and physiological findings and neurological symptoms were measured. In addition, changes in SRPX-2 in the hypothalamic injury and related factors were examined immunohistochemically. Results: The SAH group showed significant neurological deterioration, and a significant decrease in body temperature after 3 h of SAH. Expression of SRPX2 in the hypothalamus was also significantly decreased at 3 h after SAH. However, it was not associated with changes in FJC- and TUNEL-positive cells suggestive of cell death or DHE expression suggestive of oxidative stress. On the other hand, OXT showed a significant decrease after 3 hours of SAH as measured by ELISA in serum from the jugular vein. Conclusions: This is the first study to investigate the expression of SRPX2 in the hypothalamus after SAH time course. Although our results suggest that SRPX2 may not be directly associated with hypothalamic injury after SAH, the fact that SRPX2 expression was decreased during the hyperacute phase and OXT and body temperature were also decreased at the same time suggests that SRPX2 may be indirectly associated with hypothalamic injury after SAH through regulation of endocrine and autonomic function in the hypothalamic-pituitary axis. Further studies are warranted to investigate the possibility that SRPX2 may be indirectly related to hypothalamic disturbances after SAH through endocrine and autonomic regulation of the hypothalamic-pituitary axis.

Abstract TMP90: Extension of Subarachnoid Hemorrhage Following Mechanical Thrombectomy is Associated With Clinical Outcomes: A Subgroup Analysis of CLEAR Trial

Introduction: Subarachnoid hemorrhage (SAH) following mechanical thrombectomy (MT) is not uncommon. The prognostic implication for these patients remains unclear and may be affected by the extension of SAH. Methods: We included patients with SAH detected on CT after MT from CLEAR Study (The Vesalio NeVa Stent Retriever Study for Treatment of Large Vessel Occlusion Strokes). SAH was further classified according to extension degree into diffuse (> 1 extraparenchymal compartment) and non-diffuse. Unadjusted and adjusted logistic regressions were used to measure the association of both groups with modified Rankin Scale (mRS) (mRS) score at 90 days. Results: Among 139 patients, 20 SAH patients qualified for final analysis (10 with diffuse SAH: 10 with non-diffuse SAH). There were no statistically significant differences for sex, thrombolytics administration, pre mRS score, baseline NIHSS score, and procedure access (p >0.1) while there were statistically significant imbalances for age and site of occlusion (p=0.02). At the end of the procedure, there was no statistically significant difference in successful recanalization rates defined as a Modified Treatment in Cerebral Ischemia (mTICI) score of 2b or greater (100% in non-diffuse vs. 90% diffuse, P>0.99). However, non-diffuse SAH group were significantly associated with reduced disability at 90 days in both unadjusted (Common odds ratio [cOR] 11.09, 95% confidence interval [CI] (1.72-71.37), p = 0.01) and adjusted models (cOR 12.32, 95% CI 1.49-102.05, p = 0.02). Additionally, non-diffuse SAH group were significantly associated with significantly improved 90-day good functional outcomes defined as mRS 0-2 in unadjusted analysis (80% vs. 30%, OR 9.33, 95% CI 1.99-72.99, p = 0.03) but not in adjusted analysis (OR 7.84, 95% CI 0.55-109.94, p = 0.13). Median NIHSS at 24 hours was significantly lower in non-diffuse group compared to diffuse group (3 [2-6] vs. 17.5 [12-19], p< 0.001) while mortality was reduced to half but did not reach a statistical significance level (10% vs. 20%, p>0.99). Conclusions: Non-diffuse SAH was associated with better clinical outcomes compared to diffuse SAH. These findings may inform adjustable management approaches according to extension degree of SAH.

Abstract TP303: Perfluorocarbon Oxygent Limits Functional Impairment and Brain Damage Following Subarachnoid Hemorrhage

Introduction: Subarachnoid hemorrhage (SAH) is the deadliest form of hemorrhagic stroke. Post-SAH vasospasm induces brain tissue hypoxia-ischemia resulting in brain injury and functional impairments. However, translational studies focused on post-SAH brain tissue oxygenation for functional improvements remain limited. We propose the use of Oxygent, a perfluorocarbon (PFC) based lipid emulsion oxygen carrier, as a promising therapy to improve post-SAH functional outcomes. Here we propose the use of Oxygent, a perfluorocarbon (PFC), as effective therapeutics. Oxygent-PFC comes as a lipid emulsion of micro-particles with great flexibility. The ultra-smaller size of these particles as compared to RBCs lets them flow even when there is just a trickle of residual plasma and efficiently deliver oxygen to prevent tissue damage. We tested the hypothesis that Oxygent-PFC would attenuate post-SAH functional and anatomical impairments. Methods: Adult C57BL/6 wildtype mice were subjected to the endoperforation model of SAH followed by an i.v injection of Oxygent-PFC or saline (9ml/kg at 6h after SAH). At 48h after SAH, mice were tested for functional outcomes followed by blood collection through cardiac puncture. Thereafter, mice were transcardially perfused, and brains were harvested to assess various immunohistochemical and biochemical outcomes. Results and Conclusion: We found that SAH resulted in significant neurologic and motor deficits while Oxygent-PFC treatment attenuated these functional deficits. There was a significant neuronal death after SAH as compared with the sham group and Oxygent-PFC prevented neuronal death. Moreover, mitochondrial activity as assessed by OXPHOS was markedly decreased after SAH while Oxygent-PFC treatment significantly improved the mitochondrial activity as compared to the vehicle-treated SAH group. These data show that Oxygent-PFC treatment preserves mitochondrial activity, dimmish tissue damage, and improve functional outcomes. Our novel preliminary study in SAH encourages us to investigate the mechanism of action of Oxygent-PFC and a comprehensive preclinical trial to test its efficacy in different animal models of SAH.

Automated magnetic resonance imaging quantification of cerebral parenchymal and ventricular volume following subarachnoid hemorrhage: associations with cognition

This study aims to investigate cerebral parenchymal and ventricular volume changes after subarachnoid hemorrhage (SAH) and their potential association with cognitive impairment. 17 patients with aneurysmal SAH (aSAH) and 21 patients with angiographically negative SAH (anSAH) without visually apparent parenchymal loss on conventional magnetic resonance imaging (MRI) were included, along with 76 healthy controls. Volumetric analyses were performed using an automated clinical segmentation and quantification tool. Measurements were compared to on-board normative reference database (n = 1923) adjusted for age, sex, and intracranial volume. Cognition was assessed with tests for psychomotor speed, attentional control, (working) memory, executive functioning, and social cognition. All measurements took place 5 months after SAH. Lower cerebral parenchymal volumes were most pronounced in the frontal lobe (aSAH: n = 6 [35%], anSAH n = 7 [33%]), while higher volumes were most substantial in the lateral ventricle (aSAH: n = 5 [29%], anSAH n = 9 [43%]). No significant differences in regional brain volumes were observed between both SAH groups. Patients with lower frontal lobe volume exhibited significantly lower scores in psychomotor speed (U = 81, p = 0.02) and attentional control (t = 2.86, p = 0.004). Additionally, higher lateral ventricle volume was associated with poorer memory (t = 3.06, p = 0.002). Regional brain volume changes in patients with SAH without visible parenchymal abnormalities on MRI can still be quantified using a fully automatic clinical-grade tool, exposing changes which may contribute to cognitive impairment. Therefore, it is important to provide neuropsychological assessment for both SAH groups, also including those with clinically mild symptoms.

Sevoflurane Postconditioning Protects From an Early Neurological Deficit After Subarachnoid Hemorrhage: Results of a Randomized Laboratory Study in Rats.

Subarachnoid hemorrhage (SAH) is associated with neurocognitive impairment. Recent data suggest that sevoflurane attenuates edema formation after SAH in rats. However, so far, no information is available about the long-term repair phase, nor if sevoflurane impacts functionality by increasing vascularity. This study tested whether sevoflurane postconditioning would improve long-term neurologic deficit through increased formation of new vessels close to the hemorrhage area. Fifty-three animals were subjected to SAH or sham surgery with or without a 2-hour sevoflurane postconditioning (versus propofol anesthesia). Animal survival, including dropout animals due to death or reaching termination criteria, as well as neurologic deficit, defined by the Garcia score, were assessed 2 hours after recovery until postoperative day 14. On day 14, blood samples and brain tissue were harvested. Vessel density was determined by the number of cluster of differentiation 31 (CD31)-positive vessels, and activated glial cells by glial fibrillary acidic protein (GFAP)-positive astrocytes per field of view. The survival rate for sham animals was 100%, 69% in the SAH-propofol and 92% in the SAH-sevoflurane groups. According to the log-rank Mantel-Cox test, survival curves were significantly different (P = .024). The short-term neurologic deficit was higher in SAH-propofol versus SAH-sevoflurane animals 2 hours after recovery and on postoperative day 1 (propofol versus sevoflurane: 14. 6 ± 3.4 vs 15. 9 ± 2.7 points, P = .034, and 16. 2 ± 3.5 vs 17. 8 ± 0.9 points, P = .015). Overall complete recovery from neurologic deficit was observed on day 7 in both SAH groups (18. 0 ± 0.0 vs 18. 0 ± 0.0 points, P = 1.000). Cortical vascular density increased to 80. 6 ± 15.0 vessels per field of view in SAH-propofol animals (vs 71. 4 ± 10.1 in SAH-sevoflurane, P < .001). Activation of glial cells, an indicator of neuroinflammation, was assessed by GFAP-positive astrocytes GFAP per field of view. Hippocampal GFAP-positive cells were 201 ± 68 vs 179 ± 84 cells per field of view in SAH-propofol versus SAH-sevoflurane animals (P < .001). Sevoflurane postconditioning improves survival by 23% (SAH-sevoflurane versus SAH-propofol). The sevoflurane intervention could attenuate the early neurologic deficit, while the long-term outcome was similar across the groups. A higher vascular density close to the SAH area in the propofol group was not associated with improved outcomes.

Study on the effect of ginaton on reducing cerebral vasospasm and early brain injury after hemorrhagic stroke by inhibiting inflammatory response

Objective: The objective of this study was to investigate the effects and possible mechanisms of action of ginseng on cerebral vasospasm and early brain injury (EBI) following hemorrhagic stroke. Materials and Methods: Sprague-Dawley (SD) rats (n = 48) were randomly divided into sham operation (sham group), subarachnoid hemorrhage (SAH) model (SAH group), normal saline (NS group), and Ginaton (Extract of Ginkgo Biloba Leaves Drops) intervention (gin group) groups. MCP-1 mRNA and tumor necrosis factor levels were detected using reverse transcription–polymerase chain reaction. The relative expression of mRNA was detected by Western blotting. Results: (1) Compared with the sham group, the SAH, NS, and gin groups had different degrees of neurological dysfunction. Compared with the SAH and NS groups, the neurological deficits in the gin group were significantly improved (P &lt; 0.05). (2) Compared with the sham group, the relative expression levels of MCP-1 mRNA in the SAH, NS, and gin groups were 5.1 ± 0.9, 3.4 ± 0.6, and 2.5 ± 0.4, respectively; the relative expression levels of mRNA were 13.3 ± 2.4, 11.2 ± 1.8, and 3.8 ± 0.6, respectively. (3) The apoptosis rates of brain tissue in the sham, SAH, NS, and gin groups were 4.8 ± 0.7, 54.2 ± 10.3, 50.1 ± 7.4, and 28.4 ± 4.5, respectively. (4) Western blot showed that the relative expression levels of toll-like receptor-4 (TLR-4) protein in the sham, SAH, NS, and gin groups were 0.29 ± 0.03, 0.87 ± 0.15, 0.65 ± 0.13, and 0.41 ± 0.17, respectively; the relative expression levels of B protein were 0.21 ± 0.04, 0.96 ± 0.14, 0.73 ± 0.18, and 0.30 ± 0.05, respectively. Gin treatment could inhibit TLR-4 and nuclear factor-κB (NF-κB) protein expression. Conclusions: Dona tablets may inhibit activation of the NF-κB signaling pathway, and SAH-induced inflammatory response, so as to reduce cerebral vasospasm and EBI.

Protective mechanisms of tea polyphenols regulating the PI3K/Akt pathway on early brain injury after subarachnoid hemorrhage in rats.

In recent years, numerous studies have demonstrated that tea polyphenols (TPPs) can exert neuroprotective effects through the regulation of the PI3K/Akt pathway. The objective of this work was to verify whether TPPs could protect against early brain injury in rats after subarachnoid hemorrhage (SAH) by modulating the PI3K/Akt pathway. A total of 150 rats were randomly rolled into control (C), TPP, and SAH groups. The TPP and SAH groups underwent endovascular perforation to induce SAH, while C group received only endovascular needle puncture and saline injection. Brain water content, Evans Blue (EB) extravasation assay, terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) staining, Western blot, and RT-PCR analyses were performed. Relative to SAH group, TPP treatment considerably improved neurological function scores following SAH, reduced brain edema, cortical neuronal apoptosis, and blood-brain barrier damage. Levels of aquaporin-4 (AQP4) and apoptosis-related protein Bax were considerably lower in the TPP group than in SAH group. Conversely, levels of anti-apoptotic protein Bcl-2 and tight junction protein Zona occludens 1 (ZO-1) were considerably higher in the TPP group. Furthermore, TPP treatment was found to activate the PI3K/Akt signaling. TPPs can mitigate early brain injury caused by SAH in rats by reducing AQP4 levels, alleviating cortical damage, and attenuating neuronal apoptosis. These findings elucidate the protective mechanisms of TPPs against early brain injury following SAH through the regulation of the PI3K/Akt signaling.

Norad Competently Binds with Pum2 to Regulate Neuronal Apoptosis and Play a Neuroprotective Role After SAH in Mice

Subarachnoid Hemorrhage (SAH) is a cerebrovascular disorder that has been found to have severe consequences, including a high mortality and disability rate. Research has indicated that neuronal death, particularly apoptosis, plays a major role in the neurological impairment that follows SAH. RNA-binding protein Pum2 can interfere with translation or other biological functions by connecting to the UGUAHAUA sequence on RNA. Noncoding RNA activated by DNA damage (Norad) contains some Pum2 recognition sequences, which may bind to Pum2 protein and affect its capacity to attach to target mRNA. The time course expression of Norad and Pum2 after SAH is analyzed by establishing a mouse SAH model. Subsequently, the purpose of this study is to investigate the potential role and mechanism of the Norad-Pum2 axis after SAH using lentivirus overexpression of Pum2 and knockdown of Norad. Analysis of Pum2 and Norad levels reveal that the former is significantly reduce and the latter is significantly increased in the SAH group compared to the sham group. Subsequent overexpression of Pum2 and Norad knockdown is found to reduce SAH-induced oxidative stress, neuronal apoptosis, and ultimately improve behavioral and cognitive changes in SAH mice. Our study indicates that Norad-Pum2 acts as a neuromodulator in SAH, and that by increasing Pum2 and decreasing Norad levels, SAH-induced neuronal apoptosis can be reduced and neurological deficits alleviated. Consequently, Norad-Pum2 may be a promising therapeutic target for SAH.

Microsurgical Treatment of Anterior Communicating Artery Aneurysms: An Analysis of 74 Consecutive Cases. Approach Side Choice and Outcome Considerations

Abstract Introduction Anterior communicating artery aneurysms (ACoAAs) are intracranial aneurysms whose treatment is still considered a challenging task. Materials and Methods Altogether, 74 patients were included in this study. The variables included age, sex, comorbidities, incidence of subarachnoid hemorrhage (SAH), the Fisher, Hunt-Hess, and WFNS scores, approach side, length of hospital stay, and mortality. We also investigate A1/A2 dimensions, association with approach side choice and the influence of surgeon's experience on the outcome. Results There were 61 patients (82.2%) admitted with SAH and 13 were treated for unruptured aneurysms. The A1 and A2 branches were larger ipsilaterally to the selected approach side (p &lt; 0,001). No deaths occurred in the unruptured aneurysm group. In the SAH group, mortality was strongly correlated with the Hunt-Hess score (p &lt; 0.001), Fisher grade (p &lt; 0.001), and WFNS score (p &lt; 0.001). No significant difference was found in mortality between the right-side and the left-side approaches (p = 0.253). A significant survival difference was identified on the group operated by the senior surgeon versus the non-senior group (p = 0.048). Discussion and Conclusion A1 dominance was identified as a factor associated to the approach side for SAH cases at our center. Understanding the factors involved in brain aneurysm surgery remains a relevant and underexplored subject. Further studies involving larger case series and multicenter collaborations are necessary to elucidate these factors and to determine the external validity of our findings.

The influence of acelysin and nimotop on the cellular response of the hippocampus during the dynamics of experimental subarachnoid hemorrhage

Aim. Immunohistochemical study of rat hippocampal neurons and astrocytes at different time-points of experimental brain hemorrhage treated with acelysin and nimotop. Materials and methods. Subarachnoid hemorrhage (SAH) was modeled according to R. V. Dudhani et al. using 35 Wistar rats which were divided into 7 groups. Animals of the 1st and 2nd groups, for 4 and 7 days respectively received acelysin at a dose of 15 mg/kg once a day; animals of the 3rd and 4th groups received nimodipine at a dose of 0.3 mg/kg every 8 hours for 4 and 7 days. In groups 5th and 6th (control), SAH was modeled without treatment with observation periods of 4 and 7 days, respectively. The 7th group consisted of intact animals. Hippocampal CA1 fields were studied immunohistochemically evaluating the expression of CASP3, NeuN, GFAP by the relative area of immunostaining in ImageJ. Results. CASP3 expression in hippocampal neurons increases by 2.3 and 5.7 times on day 4 and by 1.8 and 3.9 times on day 7 of experimental SAH (groups 1–4) compared to intact group. GFAP expression increases in all observation groups compared to intact animals with the maximum values in the 5th group – by 8.14 times. The dynamics of NeuN expression in hippocampal neurons when using acelysin and nimotop corresponds to the inverse dynamics of CASP3 expression. The NeuN expression increases maximally on the 7th day of acelysin use and is equal to 91.76 % of the intact group values. Conclusions. The experimental SAH is accompanied by a change in the expression of CASP3, NeuN in neurons and GFAP in astrocytes. The use of acelysin and nimotop leads to decrease in CASP3 expression in hippocampal neurons on the 4th day by 3.82 and 1.54 times compared to control group, and on the 7th day by 4.00 and 1.84 times, respectively, which reflects the positive effect of the therapy on the prevention of apoptotic death of hippocampal neurons. Compared with nimotop, the use of acelicine significantly increases the expression of NeuN on day 4 and 7 – by 1.84 and 1.95 times, respectively, which indicates a more pronounced neuroprotective effect of acelysin on hippocampal neurons in SAH. Increased GFAP expression reflects the dynamic reactive remodeling of astrocytes, while the use of acelysin and nimotop does not affect the reduction of GFAP levels on days 4 and 7 of SAH and their return to baseline values. The results of the present experimental study provide a theoretical justification of the feasibility of including metabolitotropic drugs in the basic therapy of SAH.

GPR30 agonist G1 combined with hypothermia alleviates cognitive impairment and anxiety-like behavior after subarachnoid hemorrhage in rats.

This study aimed to investigate the treatment effect of G protein-coupled receptor 30 (GPR30) agonist G1 combined with hypothermia (HT) on cognitive impairment and anxiety-like behavior after subarachnoid hemorrhage (SAH) in rats. Fifty male rats were randomly assigned to one of five groups: Sham group, SAH group, SAH+G1 group, SAH+HT group, and SAH+G1+HT group. The SAH rat model was established by modified endovascular puncture in all groups except the Sham group. Neurological function after the operation was assessed by Garcia scoring. The degree of rat cerebral edema was determined using dry-wet weighing method on the 28th day after operation. Moreover, the behavioral test was performed on rats on the 4th and 28th days after operation. Compared with Sham group, the Garcia score of each SAH rat model group decreased significantly on the first day and thereafter increased gradually. However, the recovery rate of each treatment group was higher than the SAH group (no treatment), and the Garcia score of SAH+G1+HT group was much higher than the SAH group on the seventh day after operation. In addition, each treatment group could obviously reduce the cerebral edema degree of SAH rats, among which rats in SAH+G1+HT group had lower cerebral edema degree than SAH+G1 group and SAH+HT group. Behavioral test results showed that the combination of GPR30 agonist G1 and HT markedly improved the learning and memory ability of SAH rats, alleviated their anxiety- and emotion-related behavior, and enhanced their social interaction. GPR30 agonist G1 combined with HT reduces cognitive impairment and anxiety-like behavior in rats with SAH.

Pretreatment with Clodronate Improved Neurological Function by Preventing Reduction of Posthemorrhagic Cerebral Blood Flow in Experimental Subarachnoid Hemorrhage.

Brain perivascular macrophages (PVMs) are potential treatment targets for subarachnoid hemorrhage (SAH), and previous studies revealed that their depletion by clodronate (CLD) improved outcomes after experimental SAH. However, the underlying mechanisms are not well understood. Therefore, we investigated whether reducing PVMs by CLD pretreatment improves SAH prognosis by inhibiting posthemorrhagic impairment of cerebral blood flow (CBF). In total, 80 male Sprague-Dawley rats received an intracerebroventricular injection of the vehicle (liposomes) or CLD. Subsequently, the rats were categorized into the prechiasmatic saline injection (sham) and blood injection (SAH) groups after 72h. We assessed its effects on weak and severe SAH, which were induced by 200- and 300-µL arterial blood injections, respectively. In addition, neurological function at 72h and CBF changes from before the intervention to 5min after were assessed in rats after sham/SAH induction as the primary and secondary end points, respectively. CLD significantly reduced PVMs before SAH induction. Although pretreatment with CLD in the weak SAH group provided no additive effects on the primary end point, rats in the severe SAH group showed significant improvement in the rotarod test. In the severe SAH group, CLD inhibited acute reduction of CBF and tended to decrease hypoxia-inducible factor 1α expression. Furthermore, CLD reduced the number of PVMs in rats subjected to sham and SAH surgery, although no effects were observed in oxidative stress and inflammation. Our study proposes that pretreatment with CLD-targeting PVMs can improve the prognosis of severe SAH through a candidate mechanism of inhibition of posthemorrhagic CBF reduction.

Long-term Course of Cognitive Functioning After Aneurysmal and Angiographically Negative Subarachnoid Hemorrhage.

Cognitive impairment is a common consequence of subarachnoid hemorrhage (SAH), negatively affecting everyday functioning. This study is the first to investigate the long-term course of cognitive functioning after SAH and its associations with long-term well-being (ie, anxiety and depression), cognitive complaints, and return to work, separately for patients with aneurysmal SAH (aSAH) and angiographically negative SAH (anSAH) in a longitudinal design. Cognitive functioning was measured at 2 time points (T1: 3-6 months post-SAH; T2: 2-4 years post-SAH) in 58 patients with aSAH and 22 patients with anSAH with neuropsychological tests for (working) memory, psychomotor speed, and attention/executive functioning. Questionnaires were used to measure cognitive complaints and well-being at T1 and T2 and return to work at T2. At T2, patients with aSAH only showed improvements in memory and on an executive functioning and psychomotor speed subtest, whereas in contrast, patients with anSAH had significantly poorer scores on tests for psychomotor speed. A significant amount of patients with aSAH and anSAH still reported cognitive complaints, anxiety, and depression in the chronic stage. Cognitive functioning was not significantly associated with cognitive complaints in both SAH groups. On the other hand, cognitive complaints were related to well-being at the long-term in both SAH groups. More cognitive complaints were also associated with more difficulties in return to work in patients with aSAH. Patients with aSAH and anSAH have cognitive impairments at the subacute stage post-SAH, and these impairments persist into the chronic stage. Moreover, both SAH groups still reported decreased well-being in the chronic stage post-SAH, related to cognitive complaints but not to cognitive impairment. For clinical practice, an early neuropsychological assessment will already provide relevant information to estimate long-term cognitive impairment, but in addition, it is important to pay attention to psychological distress at the long-term.