Adjudin protects blood-brain barrier integrity and attenuates neuroinflammation following intracerebral hemorrhage in mice

Secondary brain injury exacerbates neurological dysfunction and neural cell death following intracerebral hemorrhage (ICH), targeting the pathophysiological mechanism of the secondary brain injury holds promise for improving ICH outcomes. Adjudin, a potential male contraceptive, exhibits neuroprotective effects in brain injury disease models, yet its impact in the ICH model remains unknown. In this study, we investigated the effects of adjudin on brain injury in a mouse ICH model and explored its underlying mechanisms. ICH was induced in male C57BL/6 mice by injecting collagenase into the right striatum. Mice received adjudin treatment (50 mg/kg/day) for 3 days before euthanization and the perihematomal tissues were collected for further analysis. Adjudin significantly reduced hematoma volume and improved neurological function compared with the vehicle group. Western blot showed that Adjudin markedly decreased the expression of MMP-9 and increased the expression of tight junctions (TJs) proteins, Occludin and ZO-1, and adherens junctions (AJs) protein VE-cadherin. Adjudin also decreased the blood-brain barrier (BBB) permeability, as indicated by the reduced albumin and Evans Blue leakage, along with a decrease in brain water content. Immunofluorescence staining revealed that adjudin noticeably reduced the infiltration of neutrophil, activation of microglia/macrophages, and reactive astrogliosis, accompanied by an increase in CD206 positive microglia/macrophages which exhibit phagocytic characteristics. Adjudin concurrently decreased the generation of proinflammatory cytokines, such as TNF-α and IL-1β. Additionally, adjudin increased the expression of aquaporin 4 (AQP4). Furthermore, adjudin reduced brain cell apoptosis, as evidenced by increased expression of anti-apoptotic protein Bcl-2, and decreased expression of apoptosis related proteins Bax, cleaved caspase-3 and fewer TUNEL positive cells. Our data suggest that adjudin protects against ICH-induced secondary brain injury and may serve as a potential neuroprotective agent for ICH treatment.

Acute evacuation of 54 intracerebral hematomas (aICH) during the microsurgical clipping of a ruptured middle cerebral artery bifurcation aneurysm-illustration of the individual clinical courses and outcomes with a serial brain CT/MRI panel until 12 months

PURPOSE

In aneurysmal intracerebral hemorrhage (aICH), our review showed the lack of the patient's individual (i) timeline panels and (ii) serial brain CT/MRI slice panels through the aICH evacuation and neurointensive care until the final brain tissue outcome.

METHODS

Our retrospective cohort consists of 54 consecutive aICH patients from a defined population who acutely underwent the clipping of a middle cerebral artery bifurcation saccular aneurysm (Mbif sIA) with the aICH evacuation at Kuopio University Hospital (KUH) from 2010 to 2019. We constructed the patient's individual timeline panels since the emergency call and serial brain CT/MRI slice panels through the aICH evacuation and neurointensive care until the final brain tissue outcome. The patients were indicated by numbers (1.-54.) in the pseudonymized panels, tables, results, and discussion.

RESULTS

The aICH volumes on KUH admission (median 46 cm3) plotted against the time from the emergency call to the evacuation (median 8 hours) associated significantly with the rebleeds (n=25) and the deaths (n=12). The serial CT/MRI slice panels illustrated the aICHs, intraventricular hemorrhages (aIVHs), residuals after the aICH evacuations, perihematomal edema (PHE), delayed cerebral injury (DCI), and in the 42 survivors, the clinical outcome (mRS) and the brain tissue outcome.

CONCLUSIONS

Regarding aICH evacuations, serial brain CT/MRI panels present more information than words, figures, and graphs. Re-bleeds associated with larger aICH volumes and worse outcomes. Swift logistics until the sIA occlusion with aICH evacuation is required, also in duty hours and weekends. Intraoperative CT is needed to illustrate the degree of aICH evacuation. PHE may evoke uncontrollable intracranial pressure (ICP) in spite of the acute aICH volume reduction.

The effect of neutrophil-to-lymphocyte ratio and systemic inflammatory response on perihematomal edema after intracerebral hemorrhage

BACKGROUND

Perihematomal edema (PHE) is a marker of secondary brain injury in patients with intracerebral hemorrhage (ICH) and is associated with increased inflammatory markers and neurological disability. This study aims to assess the effect of the neutrophile-to-lymphocyte ratio (NLR) and systemic inflammatory response syndrome (SIRS) on PHE measurements and functional status in patients with ICH.

METHODS

We included 215 patients with primary ICH and the primary outcomes were absolute and relative PHE, and edema extension distance (EED). A favorable functional outcome was defined as a modified Rankin Scale (mRS) score 0-2 measured 3 months after ICH.

RESULTS

Median age was 73.0 years (interquartile range 66-80) and 54.4% patients were males. Fifty-nine patients were functionally independent at 90 days (mRS 0 to 2). NLR and SIRS were not predictors of absolute, relative PHE, and EED when adjusted for multiple confounders. However, admission NLR was independently associated with an unfavorable functional outcome at 90 days (aOR = 0.38; 95% CI 0.17-0.87; p = 0.021).

CONCLUSIONS

NLR and SIRS are not independent predictors of absolute and relative PHE measurements following ICH. Nevertheless, NLR predicts long-term disability in ICH patients. Further research is needed to understand the mechanisms by which inflammation causes neurological injury in ICH.

An updated systematic review and meta-analysis investigating perihematomal edema and clinical outcome after intracerebral hemorrhage

OBJECTIVES

The relationship between perihematomal edema (PHE) and intracerebral hemorrhage (ICH) outcomes is uncertain. Given newly published studies, we updated a previous systematic review and meta-analysis assessing the prognostic impact of PHE on ICH outcomes.

MATERIALS AND METHODS

Databases were searched through September 2022 using pre-defined keywords. Included studies used regression to examine the association between PHE and functional outcome (assessed by modified Rankin Scale [mRS]) and mortality. The study quality was assessed using the Newcastle-Ottawa Scale. The overall pooled effect, and secondary analyses exploring different subgroups were obtained by entering the log transformed odds ratios and their confidence intervals into a DerSimonian-Laird random effects meta-analysis.

RESULTS

Twenty-eight studies (n=8655) were included. The pooled effect size for overall outcome (mRS and mortality) was 1.05 (95% CI 1.03, 1.07; p<0.00). In secondary analyses, PHE volume and growth effect sizes were 1.03 (CI 1.01, 1.05) and 1.12 (CI 1.06, 1.19), respectively. Results of subgroup analyses assessing absolute PHE volume and growth at different time points were: baseline volume 1.02 (CI 0.98, 1.06), 72-hour volume 1.07 (CI 0.99, 1.16), growth at 24 hours 1.30 (CI 0.96, 1.74) and growth at 72 hours 1.10 (CI 1.04, 1.17). Heterogeneity across studies was substantial.

CONCLUSIONS

This meta-analysis indicates that PHE growth, especially within the first 24 hours after ictus, has a stronger impact on functional outcome and mortality than PHE volume. Definitive conclusions are limited by the large variability of PHE measures, heterogeneity, and different evaluation time points between studies.

A case of intravenous iron administration resulting in cerebral edema expansion

BACKGROUND

Iron plays an important role in the development of perihematomal edema (PHE) in the setting of intracerebral hemorrhage (ICH). Cerebral iron is increased via direct hemoglobin release in ICH, and several studies have investigated the use of iron-chelating agents to mitigate its toxicity. However, the effect of systemic iron administration, corroborating the reverse concept, has never been investigated or reported clinically. We report the first case of systemic iron administration in the setting of hemorrhagic traumatic brain injury (TBI).

CASE PRESENTATION

A 46-year-old woman was admitted to the hospital with acute moderate-to-severe TBI. Her head computed tomography (CT) scan showed bifrontal hemorrhagic contusions with mild PHE. She was started on hypertonic saline 3% continuous infusion and her condition remained stable initially. She was found to be anemic and was given intravenous iron sucrose. Shortly after iron administration, her mental status declined, and left pupil became dilated and sluggish. Repeat CT demonstrated significantly worsening PHE. This prompted maximum hyperosmolar therapy and external ventricular drain (EVD) placement which both were weaned off slowly due to liable ICPs. She was discharged home after a 25-day hospital stay.

CONCLUSIONS

We believe this is the first report of exacerbating PHE accompanied by clinical decline after intravenous iron administration in the setting of acute hemorrhagic brain contusions. Though the effects of systemic iron administration on brain edema and the treatments targeting cerebral iron are poorly understood, the administration of systemic iron in acute TBI seems to be detrimental. More research is needed to address iron toxicity in TBI. Our case adds to the growing evidence for such a pathway in the treatment of ICH and TBI.

Cytotoxic Edema and Adverse Clinical Outcomes in Patients with Intracerebral Hemorrhage

BACKGROUND

Cytotoxic edema (CE) is an important form of perihematomal edema (PHE), which is a surrogate marker of secondary injury after intracerebral hemorrhage (ICH). However, knowledge about CE after ICH is insufficient. Whether CE has adverse effects on clinical outcomes of patients with ICH remains unknown. Therefore, we aimed to investigate the temporal pattern of CE and its association with clinical outcomes in patients with ICH.

METHODS

Data were derived from a randomized controlled study (comparing the deproteinized calf blood extract with placebo in patients with ICH). Intervention in this original study did not show any impact on hematoma and PHE volume, presence of CE, or clinical outcomes. We conducted our analysis in 20 patients who underwent magnetic resonance imaging with diffusion-weighted imaging (DWI) and apparent diffusion coefficient (ADC) images at day 3 and within 7-12 days after symptom onset. CE was defined as an elevated DWI b1000 signal and an ADC value reduced by > 10% compared with the mirror area of interest in the perihematomal region. The modified Rankin Scale (mRS), National Institutes of Health Stroke Scale (NIHSS), and Barthel Index (BI) were performed face to face at 30-day and 90-day follow-ups after ICH onset to assess the clinical outcomes of the patients.

RESULTS

CE was detected in nearly two thirds of patients with ICH in our study and seemed to be reversible. CE within 7-12 days, rather than at day 3 after symptom onset, was associated with poor clinical outcome (mRS 3-6) at the 30-day follow-up (P = 0.020). In addition, compared with those without CE, patients with CE within 7-12 days had more severe neurological impairment measured by NIHSS score (P = 0.024) and worse daily life quality measured by BI (P = 0.004) at both the 30- and 90-day follow-ups.

CONCLUSIONS

CE appears in the acute phase of ICH and might be reversible. CE within 7-12 days post ICH was related to poor outcomes, which provides a novel therapeutic target for ICH intervention.

Radiomics for prediction of intracerebral hemorrhage outcomes: A retrospective multicenter study

BACKGROUND

Accurate risk stratification of patients with intracerebral hemorrhage (ICH) could help refine adjuvant therapy selection and better understand the clinical course. We aimed to evaluate the value of radiomics features from hematomal and perihematomal edema areas for prognosis prediction and to develop a model combining clinical and radiomic features for accurate outcome prediction of patients with ICH.

METHODS

This multicenter study enrolled patients with ICH from January 2016 to November 2021. Their outcomes at 3 months were recorded based on the modified Rankin Scale (good, 0-3; poor, 4-6). Independent clinical and radiomic risk factors for poor outcome were identified through multivariate logistic regression analysis, and predictive models were developed. Model performance and clinical utility were evaluated in both internal and external cohorts.

RESULTS

Among the 1098 ICH patients evaluated (mean age, 60 ± 13 years), 703 (64 %) had poor outcomes. Age, hemorrhage volume and location, and Glasgow Coma Scale (GCS) were independently associated with outcomes. The area under the receiver operating characteristic curve (AUC) of the clinical model was 0.881 in the external validation cohort. Addition of the Rad-score (combined hematoma and perihematomal edema area) improved predictive accuracy and model performance (AUC, 0.893), net reclassification improvement, 0.140 (P < 0.001), and integrated discrimination improvement, 0.050 (P < 0.001).

CONCLUSIONS

The radiomics features of hematomal and perihematomal edema area have additional value in prognostic prediction; moreover, addition of radiomic features significantly improves model accuracy.

An exploratory analysis of biomarkers of perihematomal edema in the CN-105 in participants with acute supratentorial intracerebral hemorrhage (CATCH) trial

OBJECTIVE

To identify biomarkers with potential to indicate severity of perihematomal edema and secondary tissue injury after intracerebral hemorrhage (ICH), and which could be used as surrogate markers in future clinical trials for novel ICH therapeutics.

MATERIALS AND METHODS

This exploratory cohort study compared trends in neuroinflammatory biomarker levels in 18 consecutively enrolled patients with acute supratentorial ICH and 16 patients treated with the investigational neuroprotective therapy CN-105 to identify a panel of 10 biomarkers. Biomarker levels over five days post-hemorrhage were then compared with edema volumes in a larger sample of patients treated with CN-105.

RESULTS

Mean normalized edema volumes increased over time; higher CRP levels were associated with increased edema volumes (p = 0.006, r = 0.56). Higher IL8, IL10, MCP, and MMP-9 levels were associated with decreased edema volumes (p = 0.005, r =-0.57; p = 0.02, r =-0.51; p = 0.02, r =-0.52; p = .002, r =-0.63, respectively). IL1-RA, IL1-B, IL23, vWF, and IL17 levels were not significantly associated with edema volumes (p > 0.05).

CONCLUSIONS

This exploratory study provides some of the first insights into the longitudinal associations between markers of neuroinflammation and development of perihematomal edema and secondary tissue injury in human ICH. We hypothesize that these biomarkers could be used as surrogates for treatment effect in novel therapies intended to limit neuroinflammation after ICH.

Perihematomal Edema and Clinical Outcome After Intracerebral Hemorrhage: A Systematic Review and Meta-Analysis

BACKGROUND

Perihematomal edema (PHE) has been proposed as a radiological marker of secondary injury and therapeutic target in intracerebral hemorrhage (ICH). We conducted a systematic review and meta-analysis to assess the prognostic impact of PHE on functional outcome and mortality in patients with ICH.

METHODS

We searched major databases through December 2020 using predefined keywords. Any study using logistic regression to examine the association between PHE or its growth and functional outcome was included. We examined the overall pooled effect and conducted secondary analyses to explore the impact of individual PHE measures on various outcomes separately. Study quality was assessed by three independent raters using the Newcastle-Ottawa Scale. Odds ratios (per 1-unit increase in PHE) and their confidence intervals (CIs) were log transformed and entered into a DerSimonian-Laird random-effects meta-analysis to obtain pooled estimates of the effect.

RESULTS

Twenty studies (n = 6633 patients) were included in the analysis. The pooled effect size for overall outcome was 1.05 (95% CI 1.02-1.08; p < 0.00). For the following secondary analyses, the effect size was weak: mortality (1.01; 95% CI 0.90-1.14), functional outcome (1.04; 95% CI 1.02-1.07), both 90-day (1.06; 95% CI 1.02-1.11), and in-hospital assessments (1.04; 95% CI 1.00-1.08). The effect sizes for PHE volume and PHE growth were 1.04 (95% CI 1.01-1.07) and 1.14 (95% CI 1.04-1.25), respectively. Heterogeneity across studies was substantial except for PHE growth.

CONCLUSIONS

This meta-analysis demonstrates that PHE volume within the first 72 h after ictus has a weak effect on functional outcome and mortality after ICH, whereas PHE growth might have a slightly larger impact during this time frame. Definitive conclusions are limited by the large variability of PHE measures, heterogeneity, and different evaluation time points between studies.

Upregulation of AQP4 Improves Blood-Brain Barrier Integrity and Perihematomal Edema Following Intracerebral Hemorrhage

In intracerebral hemorrhage (ICH), delayed secondary neural damages largely occur from perihematomal edema (PHE) resulting from the disruption of the blood-brain barrier (BBB). PHE is often considered the principal cause of morbidity and mortality in patients with ICH. Nevertheless, the main cellular mechanism as well as the specific BBB component involved in the formation of PHE after ICH remains elusive. Herein, we evaluated the role of AQP4, a water channel expressed on the astrocytes of the BBB, in the formation of PHE in ICH. The static and dynamic functions of the BBB were evaluated by analyzing the microstructure and leakage assay. Protein changes in the PHE lesion were analyzed and the control mechanism of AQP4 expression by reactive oxygen species was also investigated. Delayed PHE formation due to BBB disruption after ICH was confirmed by the decreased coverage of multiple BBB components and increased dynamic leakages. Microstructure assay showed that among the BBB components, AQP4 showed a markedly decreased expression in the PHE lesions. The decrease in AQP4 was due to microenvironmental ROS derived from the hemorrhage and was restored by treatment with ROS scavenger. AQP4-deficient mice had significantly larger PHE lesions and unfavorable survival outcomes compared with wild-type mice. Our data identify AQP4 as a specific BBB-modulating target for alleviating PHE in ICH. Further comprehensive studies are needed to form the preclinical basis for the use of AQP4 enhancers as BBB modulators for preventing delayed cerebral edema after ICH.

Liver Fibrosis and Perihematomal Edema Growth in Primary Intracerebral Hemorrhage

BACKGROUND

Liver disease is associated with altered serum osmolality, increased thrombin generation, and systemic inflammation, all of which may contribute to perihematomal edema (PHE) after intracerebral hemorrhage (ICH). We evaluated the association between a validated liver fibrosis index and PHE growth in a cohort of patients with primary ICH.

METHODS

We performed a retrospective cohort study using data from the Virtual International Stroke Trials Archive-ICH. We included adult patients with primary ICH presenting within 6 h of symptom onset. The exposure of interest was the Fibrosis-4 (FIB-4) score, a validated liver fibrosis index; this was modeled as a continuous variable. The primary outcome was absolute PHE growth over 96 h. Secondary outcomes were absolute admission and 96-h PHE volumes. We used multiple linear regression models adjusted for established determinants of PHE. In a secondary analysis, the FIB-4 score was modeled as a categorical variable to compare patients with versus without liver fibrosis.

RESULTS

Among 354 patients with ICH, 8% had evidence of liver fibrosis based on a validated cutoff. The FIB-4 score was not associated with PHE growth in unadjusted (β, 0.03; 95% CI, - 0.01 to 0.12) or adjusted models (β, 0.04; 95% CI, - 0.03 to 0.13). In a secondary analysis treating FIB-4 as a categorical variable, patients with liver fibrosis did not have greater PHE growth than those without liver fibrosis. FIB-4 score was also not associated with absolute admission or 96-h PHE volumes.

CONCLUSIONS

In a multicenter cohort of patients with primary intracerebral hemorrhage, a liver fibrosis score was not associated with PHE volume or growth.

Impact of Perihematomal Edema on Infectious Complications after Spontaneous Intracerebral Hemorrhage

OBJECTIVE

Intracerebral hematoma involves two mechanisms leading to brain injury: the mechanical disruption of adjacent brain tissue by the hematoma and delayed neurological injury. Delayed neurological injury involves perihematomal edema (PHE) formation. Infectious complications following intracerebral hemorrhage (ICH) are a significant contributor to post-ICH recovery. We sought to identify a correlation between PHE volumes and infectious complications following ICH. We also sought to explore the clinical impact of this association.

MATERIALS AND METHODS

This retrospective study included 143 patients with spontaneous ICH. CT scans were performed on admission, and 3 h, 24 h, and 72 h following admission. Hematoma and PHE volumes were calculated using a semi-automatic method. The absolute PHE volume at each time point and changes in PHE volume (ΔPHE) were calculated. Neutrophil to lymphocyte ratio (NLR) and serum C-reactive protein (CRP) levels were measured from the obtained blood samples. Neurological deterioration (ND) was assessed in all patients.

RESULTS

Infectious complications were associated with ΔPHE_72-24 (P < 0.01), whereas there was no association between infectious complications and ΔPHE_24-3 (P = 0.09) or ΔPHE_3-ad (P = 0.81). There was a positive correlation between ΔPHE_72-24 and NLR (r = 0.85, 95% CI: 0.79-0.90, P < 0.01) and between ΔPHE_72-24 and CRP levels (r = 0.89, 95% CI: 0.84-0.92, P < 0.01). The ND rate in the group of patients with infectious complications comorbid with high ΔPHE_72-24 was higher than the other patient groups (P < 0.01).

CONCLUSIONS

This study revealed a correlation between ΔPHE_72-24 and infectious complications after spontaneous ICH, which was associated with markers of systemic inflammation. This phenotype linkage is a negative cascade that drives ND.

Sustained Low-Efficiency Dialysis is Associated with Worsening Cerebral Edema and Outcomes in Intracerebral Hemorrhage

BACKGROUND/OBJECTIVES

We postulated that renal replacement therapy (RRT) in ICH patients with advanced chronic kidney disease (CKD) is associated with increased frequency and size of perihematomal edema (PHE) expansion and worse patient outcomes.

METHODS

The Get With the Guidelines-Stroke Registry was queried for all patients admitted with ICH (N = 1089). Secondary causes, brainstem ICH, and initial HV < 7 cc were excluded. We identified patients with advanced CKD with and without RRT following admission for ICH. ABC/2 formula was used to measure hematoma volume (HV) and PHE. Patient outcomes were 30-day mortality, 90-day modified Rankin Scale score, and discharge disposition. We used propensity scores and optimal matching to adjust for multiple covariates.

RESULTS

At 48 h post-ICH, PHE expansion was a significant predictor of poor patient outcomes in our cohort. Patients with CKD who received sustained low-efficacy dialysis (SLED) treatment had larger 48 h PHE growth compared to both untreated CKD group (average treatment effect (ATE), 11.5; 95% CI, 4.9-18.1; p < 0.01) and all untreated patients (ATE, 7.43; 95% CI, 4.7-10.2; p < 0.01). Moreover, patients with RRT had significantly worse functional and mortality outcomes.

CONCLUSIONS

SLED treatment in ICH patients with CKD was associated with significant increase in rate and frequency of PHE expansion. Absolute increase in PHE during 48-h post-ICH was associated with increased mortality and worse functional outcomes. Further prospective and multicenter evaluation is needed to differentiate the effects of RRT on hematoma dynamics and patient outcomes from those attributed to CKD.

The Hounsfield Unit of Perihematomal Edema Is Associated With Poor Clinical Outcomes in Intracerebral Hemorrhage

BACKGROUND

Hounsfield unit (HU) of perihematomal edema (PHE) may be a predictor of prognosis of intracerebral hemorrhage (ICH). Our study evaluated whether PHE mean HU at the 72 hours after ICH predicts outcome, and how it compares against other PHE measures.

METHODS

Patients with ICH from a tertiary medical institution were included. PHE was segmented by the semiautomatic plane method to measure volume and mean HU. Outcomes of interest was poor 90-day prognosis (modified Rankin Scale score ≥3). Logistic regression was used to assess relationships with outcome.

RESULTS

Data from a total of 159 patients with ICH were collected. The median mean HU of PHE at 72 hours was 22.1 (IQR: 19.2-25.0). Binary logistic regression showed that the 72-hour PHE mean HU was negatively correlated with the poor prognosis of patients with ICH (OR 0.59, 95% CI 0.47-0.75, P < 0.05). The receiver operator curves of meaningful indicators revealed that the area under the curve (AUC) of PHE mean HU at 72 hours was larger and the difference of AUC between PHE mean HU with PHE absolute volume or extension distance were statistically significant (P < 0.05). The 72-hour PHE mean HU has a higher value in predicting adverse prognosis of patients with ICH.

CONCLUSIONS

The PHE mean HU at 72 hours was negatively correlated with the poor prognosis of patients with ICH. The prediction ability of PHE mean HU at 72 hours was better than PHE absolute volume and extension distance, contributing to a rather good index for predicting outcome of ICH.

Treatment Strategies to Attenuate Perihematomal Edema in Patients With Intracerebral Hemorrhage

Spontaneous intracerebral hemorrhage (SICH) continues to be a significant cause of neurologic morbidity and mortality throughout the world. Although recent advances in the treatment of SICH have significantly decreased mortality rates, functional recovery has not been dramatically improved by any intervention to date. There are 2 predominant mechanisms of brain injury from intracerebral hemorrhage: mechanical injury from the primary hematoma (including growth of that hematoma), and secondary injury from perihematomal inflammation. For instance, in the hours to weeks after SICH as the hematoma is being degraded, thrombin and iron are released and can result in neurotoxicity, free radical damage, dysregulated coagulation, and harmful inflammatory cascades; this can clinically and radiologically manifest as perihematomal edema (PHE). PHE can contribute to mass effect, cause acute neurologic deterioration in patients, and has even been associated with poor long-term functional outcomes. PHE therefore lends itself to being a potential therapeutic target. In this article, we will review 1) the pathogenesis and time course of the development of PHE, and 2) the clinical series and trials exploring various methods, with a focus on minimally invasive surgical techniques, to reduce PHE and minimize secondary brain injury. Promising areas of continued research also will be discussed.

Treatment of Edema Associated With Intracerebral Hemorrhage

OPINION STATEMENT

Cerebral edema (i.e., "brain swelling") is a common complication following intracerebral hemorrhage (ICH) and is associated with worse clinical outcomes. Perihematomal edema (PHE) accumulates during the first 72 h after hemorrhage, and during this period, patients are at risk of clinical deterioration due to the resulting tissue shifts and brain herniation. First-line medical therapies for patients symptomatic of PHE include osmotic agents, such as mannitol in low- or high-dose bolus form, or boluses of hypertonic saline (HTS) at varied concentrations with or without subsequent continuous infusion. Decompressive craniectomy may be required for symptomatic edema refractory to osmotherapy. Other strategies that reduce PHE such as hypothermia and minimally invasive surgery have shown promise in pilot studies and are currently being evaluated in larger clinical trials. Ongoing basic, translational, and clinical research seek to better elucidate the pathophysiology of PHE to identify novel strategies to prevent edema formation as a next major advance in the treatment of ICH.

High Serum MiR-130a Levels Are Associated with Severe Perihematomal Edema and Predict Adverse Outcome in Acute ICH

The development and/or progression of perihematomal edema (PHE) in patients with acute spontaneous intracerebral hemorrhage (ICH) vary substantially with different individuals. Although hematoma volume is a useful indicator for predicting PHE, its predictive power was not good at the early stage of ICH. Better predictors are urgently needed. In this study, we found that miR-130a was elevated in the serum of ICH patients and was an independent indicator positively associated with PHE volume within the first 3 days after onset. The R (2) was further evaluated when it is used in combination with hematoma mass. Serum miR-130a levels were associated with clinical outcome (National Institute of Health Stroke Scale (NIHSS) scores at day 14 and modified Rankin Scale (mRS) scores at day 90) only in patients with deep hematoma. Moreover, miR-130a was significantly increased in rat serum and perihematomal tissues and was in line with the change in brain edema. MiR-130a inhibitors reduced brain edema, blood-brain barrier (BBB) permeability, and increased neurological deficit scores, and miR-130a mimics increased monolayer permeability. Thrombin-stimulated brain microvascular endothelial cells (BMECs) were a main source of miR-130a under ICH. In the experimental model, the elevated miR-130a level was accompanied by the decreased caveolin-1 and increased matrix metalloproleinase (MMP)-2/9. Meanwhile, caveolin-1 (cav-1) was reduced by miR-130a mimics, accompanied by an increase in MMP-2/9 expression. The upregulated MMP-2/9 was then downregulated by cavtratin, a cav-1 scaffolding domain peptide. This regulation mechanism was authenticated in a thrombin-induced cellular ICH model. Our results suggest that serum miR-130a may serve as a useful early biomarker for monitoring post-ICH PHE and predicting prognosis and may be helpful in the decision-making of individualized therapy.