Alteration of the translational readthrough isoform AQP4ex induces redistribution and downregulation of AQP4 in human glioblastoma.

Glioblastoma multiforme (GBM) is characterized by a remarkable cellular and molecular heterogeneity that make the behavior of this tumor highly variable and resistant to therapy. In addition, the most serious clinical complication of GBM and other brain tumors is the development of vasogenic edema which dramatically increase the intracranial pressure. In the present study we evaluate the expression, supramolecular organization and spatial distribution of AQP4 and AQP4ex, the new readthrough isoform of AQP4, in relationship with the degree of vasogenic brain edema and tumor progression. To this purpose, tissue samples from regions of tumor core, peritumoral and non-infiltrated tissues of each GBM patient (n = 31) were analyzed. Immunofluorescence experiments revealed that the expression of AQP4ex was almost absent in tumoral regions while the canonical AQP4 isoforms appear mostly delocalized. In peritumoral tissues, AQP4 expression was found altered in those perivascular astrocyte processes where AQP4ex appeared reduced and partially delocalized. Protein expression levels measured by immunoblot showed that global AQP4 was reduced mainly in the tumor core. Notably, the relative amount of AQP4ex was more severely reduced starting from the peritumoral region. BN-PAGE experiments showed that the supramolecular organization of AQP4 is only partially affected in GBM. Edema assessment by magnetic resonance imaging revealed that the level of AQP4ex downregulation correlated with edema severity. Finally, the degree of BBB alteration, measured with sodium fluorescein content in GBM biopsies, correlated with the edema index and AQP4ex downregulation. Altogether these data suggest that the AQP4ex isoform is critical in the triggering event of progressive downregulation and mislocalization of AQP4 in GBM, which may affect the integrity of the BBB and contributes to accumulation of edema in the peritumoral tissue. Thus, AQP4ex could be considered as a potential early biomarker of GBM progression.

rhFGF20 promotes angiogenesis and vascular repair following traumatic brain injury by regulating Wnt/ß-catenin pathway.

The pathology of cerebrovascular disorders takes an important role in traumatic brain injury (TBI) by increasing intracranial pressure. Fibroblast growth factor 20 (FGF20) is a brain-derived neurotrophic factor, that has been shown to play an important role in the survival of dopaminergic neurons and the treatment of Parkinson's disease (PD). However, little is known about the role of FGF20 in the treatment of TBI and its underlying mechanism. The purpose of this study was to evaluate the protective effect of recombinant human FGF20 (rhFGF20) on protecting cerebral blood vessels after TBI. In this study, we indicated that rhFGF20 could reduce brain edema, Evans blue penetration and upregulated the expression of blood-brain barrier (BBB)-related tight junction (TJ) proteins, exerting a protective effect on the BBB in vivo after TBI. In the TBI repair phase, rhFGF20 promoted angiogenesis, neurological and cognitive function recovery. In tumor necrosis factor-α (TNF-α)-induced human brain microvascular endothelial cells (hCMEC/D3), an in vitro BBB disruption model, rhFGF20 reversed the impairment in cell migration and tube formation induced by TNF-α. Moreover, in both the TBI mouse model and the in vitro model, rhFGF20 increased the expression of ß-catenin and GSK3ß, which are the two key regulators in the Wnt/ß-catenin signaling pathway. In addition, the Wnt/ß-catenin inhibitor IWR-1-endo significantly reversed the effects of rhFGF20. These results indicate that rhFGF20 may prevent vascular repair and angiogenesis through the Wnt/ß-catenin pathway.

Behavioral alterations in long-term Toxoplasma gondii infection of C57BL/6 mice are associated with neuroinflammation and disruption of the blood brain barrier.

The Apicomplexa protozoan Toxoplasma gondii is a mandatory intracellular parasite and the causative agent of toxoplasmosis. This illness is of medical importance due to its high prevalence worldwide and may cause neurological alterations in immunocompromised persons. In chronically infected immunocompetent individuals, this parasite forms tissue cysts mainly in the brain. In addition, T. gondii infection has been related to mental illnesses such as schizophrenia, bipolar disorder, depression, obsessive-compulsive disorder, as well as mood, personality, and other behavioral changes. In the present study, we evaluated the kinetics of behavioral alterations in a model of chronic infection, assessing anxiety, depression and exploratory behavior, and their relationship with neuroinflammation and parasite cysts in brain tissue areas, blood-brain-barrier (BBB) integrity, and cytokine status in the brain and serum. Adult female C57BL/6 mice were infected by gavage with 5 cysts of the ME-49 type II T. gondii strain, and analyzed as independent groups at 30, 60 and 90 days postinfection (dpi). Anxiety, depressive-like behavior, and hyperactivity were detected in the early (30 dpi) and long-term (60 and 90 dpi) chronic T. gondii infection, in a direct association with the presence of parasite cysts and neuroinflammation, independently of the brain tissue areas, and linked to BBB disruption. These behavioral alterations paralleled the upregulation of expression of tumor necrosis factor (TNF) and CC-chemokines (CCL2/MCP-1, CCL3/MIP-1α, CCL4/MIP-1ß and CCL5/RANTES) in the brain tissue. In addition, increased levels of interferon-gamma (IFNγ), TNF and CCL2/MCP-1 were detected in the peripheral blood, at 30 and 60 dpi. Our data suggest that the persistence of parasite cysts induces sustained neuroinflammation, and BBB disruption, thus allowing leakage of cytokines of circulating plasma into the brain tissue. Therefore, all these factors may contribute to behavioral changes (anxiety, depressive-like behavior, and hyperactivity) in chronic T. gondii infection.

NLRP3 inhibition attenuates early brain injury and delayed cerebral vasospasm after subarachnoid hemorrhage.

BACKGROUND: The NLRP3 inflammasome is a critical mediator of several vascular diseases through positive regulation of proinflammatory pathways. In this study, we defined the role of NLRP3 in both the acute and delayed phases following subarachnoid hemorrhage (SAH). SAH is associated with devastating early brain injury (EBI) in the acute phase, and those that survive remain at risk for developing delayed cerebral ischemia (DCI) due to cerebral vasospasm. Current therapies are not effective in preventing the morbidity and mortality associated with EBI and DCI. NLRP3 activation is known to drive IL-1ß production and stimulate microglia reactivity, both hallmarks of SAH pathology; thus, we hypothesized that inhibition of NLRP3 could alleviate SAH-induced vascular dysfunction and functional deficits. METHODS: We studied NLRP3 in an anterior circulation autologous blood injection model of SAH in mice. Mice were randomized to either sham surgery + vehicle, SAH + vehicle, or SAH + MCC950 (a selective NLRP3 inhibitor). The acute phase was studied at 1 day post-SAH and delayed phase at 5 days post-SAH. RESULTS: NLRP3 inhibition improved outcomes at both 1 and 5 days post-SAH. In the acute (1 day post-SAH) phase, NLRP3 inhibition attenuated cerebral edema, tight junction disruption, microthrombosis, and microglial reactive morphology shift. Further, we observed a decrease in apoptosis of neurons in mice treated with MCC950. NLRP3 inhibition also prevented middle cerebral artery vasospasm in the delayed (5 days post-SAH) phase and blunted SAH-induced sensorimotor deficits. CONCLUSIONS: We demonstrate a novel association between NLRP3-mediated neuroinflammation and cerebrovascular dysfunction in both the early and delayed phases after SAH. MCC950 and other NLRP3 inhibitors could be promising tools in the development of therapeutics for EBI and DCI.

Estimation of the Morphofunctional Status of the Brain in Hypertensive Wistar Rats Using Diffusion-Weighted MRI.

Morphofunctional changes of the brain tissues of Wistar rats were studied based on the development of a multifactor cardiovasorenal model of arterial hypertension using MRI. An increase of the signal on the diffusion brain maps was recorded in 3 months, which indicated fluid accumulation in the intra- and extracellular space of the brain tissue. The data characterize the development of the pathogenetic mechanism of the hypervolemic variant of experimental arterial hypertension. The development of endothelial dysfunction in the brain vessels was manifested by predominance of abnormal constrictor reactions. In 6 months after arterial hypertension simulation, structural changes in the brain developed, such as leukoareosis, cystic encephalomalacia with dilated cerebrospinal fluid spaces and limited blood supply to brain tissue in the basins of the large cerebral arteries.

Limiting Brain Shift in Malignant Hemispheric Infarction by Decompressive Craniectomy.

OBJECTIVE: Decompressive craniectomy (DC) improves functional outcomes in selected patients with malignant hemispheric infarction (MHI), but variability in the surgical technique and occasional complications may be limiting the effectiveness of this procedure. Our aim was to evaluate predefined perioperative CT measurements for association with post-DC midline brain shift in patients with MHI. METHODS: At two medical centers we identified 87 consecutive patients with MHI and DC between January 2007 and December 2019. We used our previously tested methods to measure the craniectomy surface area, extent of transcalvarial brain herniation, thickness of tissues overlying the craniectomy, diameter of the cerebral ventricle atrium contralateral to the stroke, extension of infarction beyond the craniectomy edges, and the pre and post-DC midline brain shifts. To avoid potential confounding from medical treatments and additional surgical procedures, we excluded patients with the first CT delayed >30 hours post-DC, resection of infarcted brain, or insertion of an external ventricular drain during DC. The primary outcome in multiple linear regression analysis was the postoperative midline brain shift. RESULTS: We analyzed 72 qualified patients. The average midline brain shift decreased from 8.7 mm pre-DC to 5.4 post-DC. The only factors significantly associated with post-DC midline brain shift at the p<0.01 level were preoperative midline shift (coefficient 0.32, standard error 0.10, p=0.002) and extent of transcalvarial brain herniation (coefficient -0.20, standard error 0.05, p <0.001). CONCLUSIONS: In patients with MHI and DC, smaller post-DC midline shift is associated with smaller pre-DC midline brain shift and greater transcalvarial brain herniation. This knowledge may prove helpful in assessing DC candidacy and surgical success. Additional studies to enhance the surgical success of DC are warranted.

The role of vascular endothelial growth factor in ischemic stroke.

Ischemic stroke is an injury caused by temporary or permanent cerebral vascular occlusion. It has a high incidence, mortality, and disability rate in clinical practice, and thus poses a considerable threat to public health as one of the top three major conditions endangering human health. Vascular endothelial growth factor is a specific mitogen of endothelial cells and a protein factor that is closely related to ischemic stroke. Vascular endothelial growth factor plays an important role in a multitude of physiological and pathological conditions. As a potential angiogenic protein for the treatment of ischemic stroke, vascular endothelial growth factor plays a role in promoting angiogenesis and neuroprotection and regeneration. At the same time, it plays a role in brain edema, collateral artery formation, and atherosclerosis. An increase in vascular endothelial growth factor levels contributes to the early pathological changes in patients with stroke and is closely related to the formation of cerebral edema in ischemic stroke complications. In theory, the neuroprotective and angiogenic effects of vascular endothelial growth factor make it an ideal candidate for the treatment of stroke. Here, we review the mechanism by which vascular endothelial growth factor participates in various stages of ischemic stroke and its prospects for use in the treatment of ischemic stroke.

Mesenchymal Stem Cells: The Potential Therapeutic Cell Therapy to Reduce Brain Stroke Side Effects.

Tissue plasminogen activator (tPA) is the gold standard treatment for ischemic stroke in the time window of 3-4.5 hours after the onset of symptoms. However, tPA administration is associated with inflammation and neurotoxic effects. Mesenchymal stem cells (MSC)-based therapy is emerging as a promising therapeutic strategy to control different inflammatory conditions. This project was designed to examine the protective role of MSC administration alone or in combination with royal jelly (RJ) five hours after stroke onset. The mice model of middle cerebral artery occlusion (MCAO) was established and put to six groups, including intact (healthy mice without stroke), control (untreated stroke), treated with mouse MSC (mMSC), Sup (conditioned medium), RJ and combination of mMSC and RJ (mMSC/RJ). Thereafter, behavioral functions, serum and brain (in both infarcted and non-infarcted tissues) levels of interleukin (IL)-1ß, IL-4, IL-10, tumor necrosis factor-alpha (TNF-α) and interferon-gamma (IFN-γ) the sizes of brain infarction have been determined in the groups. Administration of mMSC and mMSC/RJ significantly improved the behavioral functions when compared to the controls. mMSC, RJ and mMSC/RJ significantly decreased the infarcted volumes. RJ and mMSC/RJ, but not mMSC, significantly decreased the brain edema. The infarction increased the serum levels of the cytokines, except TNF-α, and treatment with mMSC, Sup and RJ reduced serum levels of the pro-inflammatory cytokines. mMSC reduced IL-1ß in the non-infarcted brain tissue. To conclude, data revealed that using mMSC/RJ combination significantly reduced stroke side effects, including brain edema and serum levels of pro-inflammatory cytokines, and suggested that combination therapy of MSCs with RJ may be considered as an effective stroke therapeutic strategy.

Subacute phase of subarachnoid haemorrhage in female rats: Increased intracranial pressure, vascular changes and impaired sensorimotor function.

OBJECTIVE: Early brain injury (EBI) and delayed cerebral ischemia (DCI) after subarachnoid haemorrhage (SAH) has devastating consequences but therapeutic options and the underlying pathogenesis remain poorly understood despite extensive preclinical and clinical research. One of the drawbacks of most preclinical studies to date is that the mechanisms behind DCI after SAH are studied only in male animals. In this study we therefore established a female rat model of SAH in order to determine subacute pathophysiological changes that may contribute to DCI in females. METHODS: Experimental SAH was induced in female rats by intracisternal injection of 300 µL of autologous blood. Sham operation served as a control. Neurological deficits and intracranial pressure measurements were evaluated at both 1 and 2 days after surgery. Additionally, changes in cerebral vascular contractility were evaluated 2 days after surgery using wire myography. RESULTS: SAH in female rats resulted in sensorimotor deficits and decreased general wellbeing on both day 1 and day 2 after SAH. Intracranial pressure uniformly increased in all rats subjected to SAH on day 1. On day 2 the intracranial pressure had increased further, decreased slightly or remained at the level seen on day 1. Furthermore, female rats subjected to SAH developed cortical brain edema. Cerebral arteries, isolated 2 days after SAH, exhibited increased vascular contractions to endothelin-1 and 5-carboxamidotryptamine. CONCLUSION: In the subacute phase after SAH in female rats, we observed increased intracranial pressure, decreased wellbeing, sensorimotor deficits, increased vascular contractility and cortical brain edema. Collectively, these pathophysiological changes may contribute to DCI after SAH in females. Previous studies reported similar pathophysiological changes for male rats in the subacute phase after SAH. Thus, prevention of these gender-independent mechanisms may provide the basis for a universal treatment strategy for DCI after SAH. Nevertheless, preclinical studies of potential therapies should employ both male and female SAH models.

Idiopathic Intracranial Hypertension: Glymphedema of the Brain.

BACKGROUND: During the last decade, our understanding of cerebrospinal fluid (CSF) physiology has dramatically improved, thanks to the discoveries of both the glymphatic system and lymphatic vessels lining the dura mater in human brains. EVIDENCE ACQUISITION: We detail the recent basic science findings in the field of CSF physiology and connect them with our current understanding of the pathophysiology of idiopathic intracranial hypertension (IIH). RESULTS: Transverse sinus (TS) stenoses seem to play a major causative role in the symptoms of IIH, as a result of a decrease in the pressure gradient between the venous system and the subarachnoid space. However, the intracranial pressure can be highly variable among different patients, depending on the efficiency of the lymphatic system to resorb the CSF and on the severity of TS stenoses. It is likely that there is a subclinical form of IIH and that IIH without papilledema is probably under-diagnosed among patients with chronic migraines or isolated tinnitus. CONCLUSIONS: IIH can be summarized in the following pathological triad: restriction of the venous CSF outflow pathway-overflow of the lymphatic CSF outflow pathway-congestion of the glymphatic system. To better encompass all the stages of IIH, it is likely that the Dandy criteria need to be updated and that perhaps renaming IIH should be considered.

Uric Acid Neuroprotection Associated to IL-6/STAT3 Signaling Pathway Activation in Rat Ischemic Stroke.

Despite the promising neuroprotective effects of uric acid (UA) in acute ischemic stroke, the seemingly pleiotropic underlying mechanisms are not completely understood. Recent evidence points to transcription factors as UA targets. To gain insight into the UA mechanism of action, we investigated its effects on pertinent biomarkers for the most relevant features of ischemic stroke pathophysiology: (1) oxidative stress (antioxidant enzyme mRNAs and MDA), (2) neuroinflammation (cytokine and Socs3 mRNAs, STAT3, NF-κB p65, and reactive microglia), (3) brain swelling (Vegfa, Mmp9, and Timp1 mRNAs), and (4) apoptotic cell death (Bcl-2, Bax, caspase-3, and TUNEL-positive cells). Adult male Wistar rats underwent intraluminal filament transient middle cerebral artery occlusion (tMCAO) and received UA (16 mg/kg) or vehicle (Locke's buffer) i.v. at 20 min reperfusion. The outcome measures were neurofunctional deficit, infarct, and edema. UA treatment reduced cortical infarct and brain edema, as well as neurofunctional impairment. In brain cortex, increased UA: (1) reduced tMCAO-induced increases in Vegfa and Mmp9/Timp1 ratio expressions; (2) induced Sod2 and Cat expressions and reduced MDA levels; (3) induced Il6 expression, upregulated STAT3 and NF-κB p65 phosphorylation, induced Socs3 expression, and inhibited microglia activation; and (4) ameliorated the Bax/Bcl-2 ratio and induced a reduction in caspase-3 cleavage as well as in TUNEL-positive cell counts. In conclusion, the mechanism for morphological and functional neuroprotection by UA in ischemic stroke is multifaceted, since it is associated to activation of the IL-6/STAT3 pathway, attenuation of edematogenic VEGF-A/MMP-9 signaling, and modulation of relevant mediators of oxidative stress, neuroinflammation, and apoptotic cell death.

E2-BSA and G1 exert neuroprotective effects and improve behavioral abnormalities following traumatic brain injury: The role of classic and non-classic estrogen receptors.

The role of classical and non-classical estrogen receptors (ERs) in mediating the neuroprotective effects of this hormone on brain edema and long-term behavioral disorders was evaluated after traumatic brain injury (TBI). Ovariectomized rats were divided as follows: E2 (17 ß-estradiol), E2-BSA (E2 conjugated to bovine serum albumin), G1 [G-protein-coupled estrogen receptor agonist (GPER)] or their vehicle was injected following TBI, whereas ICI (classical estrogen receptor antagonist), G15 (GPER antagonist), ICI + G15, and their vehicle were injected before the induction of TBI and the injection of E2 and E2-BSA. Brain water (BWC) and Evans blue (EB) contents were measured 24 h and 5 h after TBI, respectively. Intracranial pressure (ICP) and cerebral perfusion pressure (CPP) were measured before and at different times after TBI. Locomotor activity, anxiety-like behavior, and spatial memory were assessed on days 3, 7, 14, and 21 after injury. E2, E2-BSA, and G1 prevented the increase of BWC and EB content after TBI, and these effects were inhibited by ICI and G15. ICI and G15 also inhibited the beneficial effects of E2, E2-BSA on ICP, as well as CPP, after trauma. E2, E2-BSA, and G1 prevented the cognitive deficiency and behavioral abnormalities induced by TBI. Similar to the above parameters, ICI and G15 also reversed this E2 and E2-BSA effects on days 3, 7, 14, and 21. Our findings indicated that the beneficial effects of E2-BSA and E2 were inhibited by both ICI and G15, suggesting that GPER and classic ERs were involved in mediating the long-term effects of E2.

Effect of Recanalization on Cerebral Edema, Long-Term Outcome, and Quality of Life in Patients with Large Hemispheric Infarctions.

OBJECTIVES: Space-occupying cerebral edema is the main cause of mortality and poor functional outcome in patients with large cerebral artery occlusion (LVO). We aimed to determine whether recanalization of LVO would augment cerebral edema volume and the impact on functional outcome and quality of life (QoL). MATERIALS AND METHODS: Prospectively, 43 patients with large middle cerebral artery territory infarction or NIHSS ≥ 12 on admission were enrolled. The degree of recanalization (partial and complete versus no recanalization) was assessed by computed tomography (CT)-angiography or Duplex ultrasound more than 24 h after symptom onset. Cerebral edema volume was measured on follow up CTs by computer-based planimetry. Mortality, functional outcome (by modified Ranking Scale (mRS) and Barthel Index (BI)) were assessed at discharge and 12 months, and QoL (by SF-36 and EQ-5D-3L) at 12 months. RESULTS: Mean cerebral edema volume was 333±141 ml without recanalization (n=13, group 1) and 276±140 ml with partial or complete recanalization (n=30, group 2, p= 0.23). There were no significant differences in mortality at discharge (38% versus 23%), at 12 months (58% versus 48%), in functional outcome at discharge (mRS 0-3: 0% both; mRS 4-5: 62% versus 77%) and at 12 months (mRS 0-3: 0% versus 11%; mRS 4-5: 42% versus 41%). The BI improved significantly from discharge to 12 months only in group 2 (p=0.001). Mean physical component score in SF-36 was 25.6±6.4, psychological component score was 41.9±14.1. In the EQ-5D-3L, most patients reported problems with activities of daily living, reduced mobility, and selfcare. CONCLUSIONS: Recanalization of a large cerebral artery occlusion in the anterior circulation territories is not associated with amplification of post-ischemic cerebral edema but may be correlated with better long-term functional outcome. QoL was low and mainly dependent on physical disability. The association between recanalization, collateral status and development of cerebral edema after LVO and the effect on functional outcome and quality of life should be explored in a larger patient population.

Higher vascularity at infiltrated peripheral edema differentiates proneural glioblastoma subtype.

BACKGROUND AND PURPOSE: Genetic classifications are crucial for understanding the heterogeneity of glioblastoma. Recently, perfusion MRI techniques have demonstrated associations molecular alterations. In this work, we investigated whether perfusion markers within infiltrated peripheral edema were associated with proneural, mesenchymal, classical and neural subtypes. MATERIALS AND METHODS: ONCOhabitats open web services were used to obtain the cerebral blood volume at the infiltrated peripheral edema for MRI studies of 50 glioblastoma patients from The Cancer Imaging Archive: TCGA-GBM. ANOVA and Kruskal-Wallis tests were carried out in order to assess the association between vascular features and the Verhaak subtypes. For assessing specific differences, Mann-Whitney U-test was conducted. Finally, the association of overall survival with molecular and vascular features was assessed using univariate and multivariate Cox models. RESULTS: ANOVA and Kruskal-Wallis tests for the maximum cerebral blood volume at the infiltrated peripheral edema between the four subclasses yielded false discovery rate corrected p-values of <0.001 and 0.02, respectively. This vascular feature was significantly higher (p = 0.0043) in proneural patients compared to the rest of the subtypes while conducting Mann-Whitney U-test. The multivariate Cox model pointed to redundant information provided by vascular features at the peripheral edema and proneural subtype when analyzing overall survival. CONCLUSIONS: Higher relative cerebral blood volume at infiltrated peripheral edema is associated with proneural glioblastoma subtype suggesting underlying vascular behavior related to molecular composition in that area.

Hydrogen gas inhalation improves delayed brain injury by alleviating early brain injury after experimental subarachnoid hemorrhage.

Molecular hydrogen (H2) protect neurons against reactive oxygen species and ameliorates early brain injury (EBI) after subarachnoid hemorrhage (SAH). This study investigated the effect of H2 on delayed brain injury (DBI) using the rat SAH + unilateral common carotid artery occlusion (UCCAO) model with the endovascular perforation method. 1.3% H2 gas (1.3% hydrogen premixed with 30% oxygen and balanced nitrogen) inhalation was performed on days 0 and 1, starting from anesthesia induction and continuing for 2 h on day 0, and starting from anesthesia induction and continuing for 30 min on day 1. EBI was assessed on the basis of brain edema, expression of S100 calcium-binding protein B (S100B), and phosphorylation of C-Jun N-terminal kinase on day 2, and neurological deficits on day 3. Reactive astrogliosis and severity of cerebral vasospasm (CV) were assessed on days 3 and 7. DBI was assessed on the basis of neurological deficits and neuronal cell death on day 7. EBI, reactive astrogliosis, and DBI were ameliorated in the H2 group compared with the control group. CV showed no significant improvement between the control and H2 groups. This study demonstrated that H2 gas inhalation ameliorated DBI by reducing EBI without improving CV in the rat SAH + UCCAO model.

Asymmetric cerebral edema presenting with severe neurologic impairment and seizures after cardiac and thoracic interventions.

INTRODUCTION: A syndrome of focal neurologic deficits with characteristic imaging features, acute encephalopathy, and seizures after cardiac and thoracic interventions has been previously briefly reported in the literature. In a retrospective observational study, we aim to identify the prevalence and characteristics of this syndrome, in addition to discussing the possible underlying pathophysiology. METHODS: In a retrospective study, we reviewed records of consecutive adult patients (≥18 years old) who underwent cardiac and thoracic procedures at a single institution between September 2014 to September 2019 and found to have evidence of focal cerebral edema following their procedure. We included and reported clinical course of patients who developed post-operative neurologic dysfunction and underwent magnetic resonance imaging (MRI) showing (1) asymmetric cerebral edema with (2) cortical diffusion restriction and (3) T2 cortical or subcortical hyperintensity and (4) no proximal vascular occlusion. RESULTS: Three out of 107 patients (2.8%) met our inclusion criteria. These represented one male and two females with age at presentation of 63, 81 and 69, respectively. All patients developed severe neurologic impairment on the same day following their procedure (sternotomy with valve or bypass surgery in 2 patients; esophageal dilatation procedure in 1 patient). All patients underwent MRI of the brain and vessel imaging qualifying our inclusion criteria. Two patients improved neurologically prior to discharge, and one patient expired after family elected to withdraw care. CONCLUSION: We present a series of cases with a rare syndrome after cardiac and thoracic interventions. Although the exact mechanism of this syndrome remains unclear, we believe it to be related to relative cerebral hyperperfusion and cerebral dysautoregulation following anesthesia and thoracic manipulation. Future studies should focus on understanding the true prevalence and pathophysiology of this syndrome.

Clinical and Imaging Features of Contrast-Induced Neurotoxicity After Neurointerventional Surgery.

BACKGROUND: Contrast-induced neurotoxicity (CIN) is an infrequent complication of endovascular procedures, and its understanding remains poor. We aimed to study and characterize the clinical and imaging features of a case series of CIN after neurointerventional surgery. METHODS: We reviewed all neuroendovascular consecutive procedures from September 2014 to November 2018. CIN was defined as new onset of neurologic deficits that occurred postoperatively after excluding other conditions. All demographic, clinical, procedural, and radiologic data were retrospectively analyzed and collected. RESULTS: Eleven cases of CIN in 1587 patients were identified out of 2510 procedures. The median age was 76 years (interquartile range [IQR], 65-81). The most common comorbidity was hypertension (82%). Median procedure time was 100 minutes (IQR, 80-130.5 minutes). All patients showed wide variability in intraprocedural blood pressure (BP) recordings with fluctuations from the baseline BP. Systolic BP ranged from 83 mm Hg below the patient baseline to 80 mm Hg above baseline. The median symptom onset was 4 hours (IQR, 0.8-9.5 hours). The CIN signs and symptoms presented gradually, initially with encephalopathy and later with focal signs. All patients had an initial computed tomography scan, which showed ipsilateral cerebral edema in 82% of patients. Two had contrast enhancement. Complete resolution of CIN symptoms was obtained in a median time of 3 days (IQR, 2.5-3 days). CONCLUSIONS: CIN should be considered in the context of the progressive onset of neurologic deficits after neuroendovascular procedures. A distinct imaging pattern of ipsilateral hemisphere edema in the absence of ischemia is usually identified. Variability in procedural BP might be a predisposing factor.

Osmotherapy for malignant cerebral edema in a phase 2 prospective, double blind, randomized, placebo-controlled study of IV glibenclamide.

BACKGROUND/OBJECTIVE: Malignant edema can be a life-threatening complication of large hemispheric infarction (LHI), and is often treated with osmotherapy. In this exploratory analysis of data from the GAMES-RP study, we hypothesized that patients receiving osmotherapy had symptomatic cerebral edema, and that treatment with intravenous (IV) glibenclamide would modify osmotherapy use as compared with placebo. METHODS: GAMES-RP was a phase 2 multi-center prospective, double blind, randomized, placebo-controlled study in LHI. Patients were randomized to IV glibenclamide (e.g. IV glyburide) or placebo. Cerebral edema therapies included osmotherapy and/or decompressive craniectomy at the discretion of the treating team. Total bolus osmotherapy dosing was quantified by "osmolar load". Radiographic edema was defined by dichotomizing midline shift at 24 h. Clinical changes were defined as any increase in NIHSS1a. RESULTS: Osmotherapy was administered to 40 of the 77 patients at a median of 39 [27-55] h after stroke onset. The median baseline DWI lesion volume was significantly larger in the osmotherapy treated group (167 [146-211] mL v. 139 [112-170] mL; P=0.046). Adjudicated malignant edema (75% v. 16%; P<0.001) was more common in the osmotherapy treated group. There were no differences in the proportion of patients receiving osmotherapy or the median total osmolar load between treatment arms. Most patients (76%) had a decrease in consciousness (NIHSS item 1A ≥1) on the day they began receiving osmotherapy. CONCLUSIONS: In the GAMES-RP trial, osmolar therapies were most often administered in response to clinical symptoms of decreased consciousness. However, the optimal timing of administration and impact on outcome after LHI have yet to be defined.

MST4 Kinase Inhibitor Hesperadin Attenuates Autophagy and Behavioral Disorder via the MST4/AKT Pathway in Intracerebral Hemorrhage Mice.

BACKGROUND: The aim of this study was to explore the role of hesperadin in intracerebral hemorrhage (ICH) mice, with the involvement of the mammalian ste20-like kinase 4 (MST4)/AKT signaling pathway. METHODS: All mice were divided into four groups: sham group, sham+hesperidin group, ICH group, and ICH+hesperadin group. The effects of hesperadin were assessed on the basis of brain edema and neurobehavioral function. Furthermore, we observed MST4, AKT, phosphorylation of AKT (pAKT), and microtubule-associated protein light chain 3 (LC3) by western blotting. Protein localization of MST4 and LC3 was determined by immunofluorescence. RESULTS: The expression of MST4 was upregulated at 12 h and 24 h after ICH. Brain edema was significantly decreased and neurological function was improved in the hesperadin treatment group compared to the ICH group (P < 0.05). Hesperadin decreases the expressions of MST and increases pAKT after ICH. Autophagy significantly increased in the ICH group, while hesperadin reduced this increase. CONCLUSION: Hesperadin provides neuroprotection against ICH by inhibiting the MST4/AKT signaling pathway.

Basic Fibroblast Growth Factor (bFGF) Protects the Blood-Brain Barrier by Binding of FGFR1 and Activating the ERK Signaling Pathway After Intra-Abdominal Hypertension and Traumatic Brain Injury.

BACKGROUND Intra-abdominal hypertension (IAH) is associated with high morbidity and mortality. IAH leads to intra-abdominal tissue damage and causes dysfunction in distal organs such as the brain. The effect of a combined injury due to IAH and traumatic brain injury (TBI) on the integrity of the blood-brain barrier (BBB) has not been investigated. MATERIAL AND METHODS Intracranial pressure (ICP) monitoring, brain water content, EB permeability detection, immunofluorescence staining, real-time PCR, and Western blot analysis were used to examine the effects of IAH and TBI on the BBB in rats, and to characterize the protective effects of basic fibroblast growth factor (bFGF) on combined injury-induced BBB damage. RESULTS Combined injury from IAH and TBI to the BBB resulted in brain edema and increased intracranial pressure. The effects of bFGF on alleviating the rat BBB injuries were determined, indicating that bFGF regulated the expression levels of the tight junction (TJ), adhesion junction (AJ), matrix metalloproteinase (MMP), and IL-1ß, as well as reduced BBB permeability, brain edema, and intracranial pressure. Moreover, the FGFR1 antagonist PD 173074 and the ERK antagonist PD 98059 decreased the protective effects of bFGF. CONCLUSIONS bFGF effectively protected the BBB from damage caused by combined injury from IAH and TBI, and binding of FGFR1 and activation of the ERK signaling pathway was involved in these effects.