Pediatric Primary Dural Lymphoblastic B-cell Lymphoma Presenting as Hematoma in the Frontoparietal Region: A Case Report.

Lymphomas originating from the meninges without brain or systemic involvement represent an extremely rare type of primary central nervous system lymphomas. Here, we report a case of primary dural lymphoma in a 3-year-old boy who was brought to the hospital due to headache, nausea, and vomiting episodes ongoing for several days. An acute hematoma in the right frontoparietal region was detected on a brain CT scan. The patient underwent surgery to remove the hematoma, which was then sent for pathologic examination. The pathology report revealed lymphoblastic B-cell lymphoma with a Ki-67 proliferation index of 80%. Radiologic and FDG-PET/CT imaging, as well as bone marrow examination, did not reveal any systemic disease. The NHL BFM 2012 lymphoblastic lymphoma treatment protocol was started and successfully completed. The patient has been followed for ~2 years and is still alive and disease-free. This is the first case of pediatric primary dural lymphoblastic B-cell lymphoma ever reported in the literature.

Effects of intestinal flora on cerebral hemorrhage area and brain tissue inflammation in acute hemorrhagic stroke.

To explore the impacts of intestinal flora on cerebral hemorrhage area and brain tissue inflammation in acute hemorrhagic stroke, seventy-two male C57BL/6 mice were randomly separated into 6 groups (n=12), the experimental group (EG, day 1, day 3 and day 7) and the control group (CG, day 1, day 3 and day 7). The mouse cerebral hemorrhage model was established by collagenase injection, and the EG received 0.4 mL fecal filtrate of healthy mice once a day, and the CG received the same amount of normal saline transplantation. The mNSS score, hematoma volume and cerebral edema content were used to evaluate nerve function injury and brain injury degree at each time point after operation. The expressions of inflammatory factors were detected by western blot. We found that at each time point after operation, compared with the CG, nerve function deficit scores of mice in the EG declined (P<0.05), the water content of mice brain tissue in the EG declined (P<0.05), and the protein expressions of inflammatory factors in the EG were decreased (P<0.05). Relative to the CG, the volume of hematoma in the EG declined on day 3 along with day 7 after operation (P<0.05). In conclusion, intestinal flora can reduce cerebral hemorrhage area and brain tissue inflammation, and then improve the performance of nerve function deficit in acute hemorrhagic stroke.

A comprehensive prediction model predicts perihematomal edema growth in the acute stage after intracerebral hemorrhage.

BACKGROUND: Perihematomal edema (PHE) is regarded as a potential intervention indicator of secondary injury following intracerebral hemorrhage (ICH). But it still lacks a comprehensive prediction model for early PHE formation. METHODS: The included ICH patients have received an initial Computed Tomography scan within 6 hours of symptom onset. Hematoma volume and PHE volume were computed using semiautomated computer-assisted software. The volume of the hematoma, edema around the hematoma, and surface area of the hematoma were calculated. The platelet-to-lymphocyte ratio (PLR) was calculated by dividing the platelet count by the lymphocyte cell count. All analyses were 2-tailed, and the significance level was determined by P <0.05. RESULTS: A total of 226 patients were included in the final analysis. The optimal cut-off values for PHE volume increase to predict poor outcomes were determined as 5.5 mL. For clinical applicability, we identified a value of 5.5 mL as the optimal threshold for early PHE growth. In the multivariate logistic regression analyses, we finally found that baseline hematoma surface area (p < 0.001), expansion-prone hematoma (p < 0.001), and PLR (p = 0.033) could independently predict PHE growth. The comprehensive prediction model demonstrated good performance in predicting PHE growth, with an area under the curve of 0.841, sensitivity of 0.807, and specificity of 0.732. CONCLUSION: In this study, we found that baseline hematoma surface area, expansion-prone hematoma, and PLR were independently associated with PHE growth. Additionally, a risk nomogram model was established to predict the PHE growth in patients with ICH.

Spontaneously ruptured huge hepatic subcapsular hematoma associated with preeclampsia: A case report and literature review.

Hepatic subcapsular hematoma (HSH) is an uncommon complication of pregnancy and is associated with elevated rates of maternal and foetal mortality. The rupture of an HSH is a critical situation that necessitates immediate and timely intervention to prevent loss of life. We present here, a case of a spontaneously ruptured massive HSH caused by preeclampsia. In addition, we conducted a comprehensive review of existing literature, encompassing 49 cases of HSH associated with pregnancy. If a pregnant woman with gestational hypertension experiences right upper abdominal pain with shoulder pain or radiating shoulder pain, it is crucial for her to have an urgent abdominal ultrasound because of the potential development of HSH and/or rupture. Our review of current literature suggests that opting for a caesarean section may offer notable advantages in preventing HSH rupture.

Research advances in predicting the expansion of hypertensive intracerebral hemorrhage based on CT images: an overview.

Hematoma expansion (HE) is an important risk factor for death or poor prognosis in patients with hypertensive intracerebral hemorrhage (HICH). Accurately predicting the risk of HE in patients with HICH is of great clinical significance for timely intervention and improving patient prognosis. Many imaging signs reported in literatures showed the important clinical value for predicting HE. In recent years, the development of radiomics and artificial intelligence has provided new methods for HE prediction with high accuracy. Therefore, this article reviews the latest research progress in CT imaging, radiomics, and artificial intelligence of HE, in order to help identify high-risk patients for HE in clinical practice.

Acute upper airway obstruction due to cervical hematoma after cervicofacial liposuction.

Liposuction is a surgical procedure performed worldwide. Although many fatal complications of liposuction have been reported, to our knowledge, no cases of fatal liposuction complications specifically related to the face region have been reported. Here, we present a case of a woman in her 30s who developed a cervical hematoma and upper airway obstruction following facial liposuction. We present this unique case to highlight the rare occurrence of fatal complications specific to facial liposuction. The patient underwent liposuction during surgery at a cosmetic surgical clinic and awoke from anesthesia after the procedure. Two hours later, she developed a neck swelling and dyspnea. While the anesthesiologist managed her airway, she went into cardiopulmonary arrest. She was then transferred to the emergency room but died on day 7 of hospitalization. The autopsy revealed swelling of the right cheek and mandible, a subcutaneous hematoma in the same area, and laryngeal edema. A damaged facial artery branch was identified, which was consistent with the computed tomography (CT) findings on admission. CT also showed that the hematoma compressed the right internal jugular vein, suggesting that venous outflow impairment caused by the hematoma may have exacerbated the airway obstruction. This case reveals that cervical hematoma caused by facial liposuction can cause fatal upper airway obstruction and the onset of the hematoma may be gradual.

Single-cell RNA sequencing reveals the evolution of the immune landscape during perihematomal edema progression after intracerebral hemorrhage.

BACKGROUND: Perihematomal edema (PHE) after post-intracerebral hemorrhage (ICH) has complex pathophysiological mechanisms that are poorly understood. The complicated immune response in the post-ICH brain constitutes a crucial component of PHE pathophysiology. In this study, we aimed to characterize the transcriptional profiles of immune cell populations in human PHE tissue and explore the microscopic differences between different types of immune cells. METHODS: 9 patients with basal ganglia intracerebral hemorrhage (hematoma volume 50-100 ml) were enrolled in this study. A multi-stage profile was developed, comprising Group1 (n = 3, 0-6 h post-ICH, G1), Group2 (n = 3, 6-24 h post-ICH, G2), and Group3 (n = 3, 24-48 h post-ICH, G3). A minimal quantity of edematous tissue surrounding the hematoma was preserved during hematoma evacuation. Single cell RNA sequencing (scRNA-seq) was used to map immune cell populations within comprehensively resected PHE samples collected from patients at different stages after ICH. RESULTS: We established, for the first time, a comprehensive landscape of diverse immune cell populations in human PHE tissue at a single-cell level. Our study identified 12 microglia subsets and 5 neutrophil subsets in human PHE tissue. What's more, we discovered that the secreted phosphoprotein-1 (SPP1) pathway served as the basis for self-communication between microglia subclusters during the progression of PHE. Additionally, we traced the trajectory branches of different neutrophil subtypes. Finally, we also demonstrated that microglia-produced osteopontin (OPN) could regulate the immune environment in PHE tissue by interacting with CD44-positive cells. CONCLUSIONS: As a result of our research, we have gained valuable insight into the immune-microenvironment within PHE tissue, which could potentially be used to develop novel treatment modalities for ICH.

Mas receptor activation facilitates innate hematoma resolution and neurological recovery after hemorrhagic stroke in mice.

BACKGROUND: Intracerebral hemorrhage (ICH) is a devastating neurological disease causing severe sensorimotor dysfunction and cognitive decline, yet there is no effective treatment strategy to alleviate outcomes of these patients. The Mas axis-mediated neuroprotection is involved in the pathology of various neurological diseases, however, the role of the Mas receptor in the setting of ICH remains to be elucidated. METHODS: C57BL/6 mice were used to establish the ICH model by injection of collagenase into mice striatum. The Mas receptor agonist AVE0991 was administered intranasally (0.9 mg/kg) after ICH. Using a combination of behavioral tests, Western blots, immunofluorescence staining, hematoma volume, brain edema, quantitative-PCR, TUNEL staining, Fluoro-Jade C staining, Nissl staining, and pharmacological methods, we examined the impact of intranasal application of AVE0991 on hematoma absorption and neurological outcomes following ICH and investigated the underlying mechanism. RESULTS: Mas receptor was found to be significantly expressed in activated microglia/macrophages, and the peak expression of Mas receptor in microglia/macrophages was observed at approximately 3-5 days, followed by a subsequent decline. Activation of Mas by AVE0991 post-treatment promoted hematoma absorption, reduced brain edema, and improved both short- and long-term neurological functions in ICH mice. Moreover, AVE0991 treatment effectively attenuated neuronal apoptosis, inhibited neutrophil infiltration, and reduced the release of inflammatory cytokines in perihematomal areas after ICH. Mechanistically, AVE0991 post-treatment significantly promoted the transformation of microglia/macrophages towards an anti-inflammatory, phagocytic, and reparative phenotype, and this functional phenotypic transition of microglia/macrophages by Mas activation was abolished by both Mas inhibitor A779 and Nrf2 inhibitor ML385. Furthermore, hematoma clearance and neuroprotective effects of AVE0991 treatment were reversed after microglia depletion in ICH. CONCLUSIONS: Mas activation can promote hematoma absorption, ameliorate neurological deficits, alleviate neuron apoptosis, reduced neuroinflammation, and regulate the function and phenotype of microglia/macrophages via Akt/Nrf2 signaling pathway after ICH. Thus, intranasal application of Mas agonist ACE0991 may provide promising strategy for clinical treatment of ICH patients.

Peri-hematomal edema shape features related to 3-month outcome in acute supratentorial intracerebral hemorrhage.

INTRODUCTION: Perihematomal edema (PHE) represents secondary brain injury and a potential treatment target in intracerebral hemorrhage (ICH). However, studies differ on optimal PHE volume metrics as prognostic factor(s) after spontaneous, non-traumatic ICH. This study examines associations of baseline and 24-h PHE shape features with 3-month outcomes. PATIENTS AND METHODS: We included 796 patients from a multicentric trial dataset and manually segmented ICH and PHE on baseline and follow-up CTs, extracting 14 shape features. We explored the association of baseline, follow-up, difference (baseline/follow-up) and temporal rate (difference/time gap) of PHE shape changes with 3-month modified Rankin Score (mRS) - using Spearman correlation. Then, using multivariable analysis, we determined if PHE shape features independently predict outcome adjusting for patients' age, sex, NIH stroke scale (NIHSS), Glasgow Coma Scale (GCS), and hematoma volume. RESULTS: Baseline PHE maximum diameters across various planes, main axes, volume, surface, and sphericity correlated with 3-month mRS adjusting for multiple comparisons. The 24-h difference and temporal change rates of these features had significant association with outcome - but not the 24-h absolute values. In multivariable regression, baseline PHE shape sphericity (OR = 2.04, CI = 1.71-2.43) and volume (OR = 0.99, CI = 0. 98-1.0), alongside admission NIHSS (OR = 0.86, CI = 0.83-0.88), hematoma volume (OR = 0.99, CI = 0. 99-1.0), and age (OR = 0.96, CI = 0.95-0.97) were independent predictors of favorable outcomes. CONCLUSION: In acute ICH patients, PHE shape sphericity at baseline emerged as an independent prognostic factor, with a less spherical (more irregular) shape associated with worse outcome. The PHE shape features absolute values over the first 24 h provide no added prognostic value to baseline metrics.

External Mechanical Stability Regulates Hematoma Vascularization in Bone Healing Rather than Endothelial YAP/TAZ Mechanotransduction.

Bone fracture healing is regulated by mechanobiological cues. Both, extracellular matrix (ECM) deposition and microvascular assembly determine the dynamics of the regenerative processes. Mechanical instability as by inter-fragmentary shear or compression is known to influence early ECM formation and wound healing. However, it remains unclear how these external cues shape subsequent ECM and microvascular network assembly. As transcriptional coactivators, the mechanotransducers yes-associated protein 1 (YAP)/transcriptional coactivator with PDZ-binding motif (TAZ) translate physical cues into downstream signaling events, yet their role in sprouting angiogenesis into the hematoma after injury is unknown. Using bone healing as model system for scar-free regeneration, the role of endothelial YAP/TAZ in combination with tuning the extrinsic mechanical stability via fracture fixation is investigated. Extrinsically imposed shear across the gap delayed hematoma remodeling and shaped the morphology of early collagen fiber orientations and microvascular networks, suggesting that enhanced shear increased the nutrient exchange in the hematoma. In contrast, endothelial YAP/TAZ deletion has little impact on the overall vascularization of the fracture gap, yet slightly increases the collagen fiber deposition under semi-rigid fixation. Together, these data provide novel insights into the respective roles of endothelial YAP/TAZ and extrinsic mechanical cues in orchestrating the process of bone regeneration.

Application of high-resolution magnetic resonance vessel wall image in the treatment of M1 segment stenosis of middle cerebral artery.

OBJECTIVE: To investigate the application of high-resolution magnetic resonance vessel wall image (HRMR-VWI) in treating middle cerebral artery (MCA) M1 segment stenosis. METHODS: We retrospectively analyzed preoperative clinical data, imaging data, preoperative evaluation, stent procedure, and postoperative complications in 35 patients with atherosclerotic stenosis of the MCA M1 segment. And the 30-day postoperative mortality and disability and the 12-month restenosis were followed up. RESULTS: There were 21 males and 14 females, with a median age of 55 and a median duration of 1 month from onset to stenting. DSA confirmed that the stenosis locates in the M1 segment, with a stenosis degree of (75.00 ± 17.15) %, a stenosis length of (4.34 ± 1.51) mm, and a blood vessel diameter of (2.25 ± 0.42) mm. After the operation, there was 1 case of death after a craniotomy to remove hematoma + decompression due to reperfusion hemorrhage. There were two technical complications during the procedure (1 case of asymptomatic occlusion of the A1 segment due to the covering of stent at the initial part of A1, 1 case of intraparenchymal hematoma in the temporal lobe due to penetrating distal small blood vessel with guide wire). CONCLUSION: HRMR-VWI is of great value in observing plaques' location, morphology, and stability. It can improve the safety and effectiveness of stenting treatment of MCA M1 segment stenosis.

Intramural Duodenal Hematoma in a Case of Hyper IgM Syndrome.

Three-year-old boy who presented with colicky abdominal pain, diarrhoea and vomiting was investigated with computed tomography which revealed a mass in the peripancreatic region. An imaging possibility of duodenal intramural hematoma was considered after reassessment with ultrasound which was subsequently confirmed by magnetic resonance imaging. The development of a spontaneous duodenal hematoma lead to further evaluation of the patient and revealed X linked hyper IgM syndrome.

Imaging of pediatric skull lytic lesions: A review.

Skull lesions in pediatric population are common findings on imaging and sometimes with heterogeneous manifestations, constituting a diagnostic challenge. Some lesions can be misinterpreted for their aggressiveness, as with larger lesions eroding cortical bone, containing soft tissue components, leading to excessive and, in some cases, invasive inappropriate etiological investigation. In this review, we present multiple several conditions that may present as skull lesions or pseudolesions, organized by groups (anatomic variants, congenital and development disorders, traumatic injuries, vascular issues, infectious conditions, and tumoral processes). Anatomic variants are common imaging findings that must be recognized by the neuroradiologist. Congenital malformations are rare conditions, such as aplasia cutis congenita and sinus pericranii, usually seen at earlier ages, the majority of which are benign findings. In case of trauma, cephalohematoma, growing skull fractures, and posttraumatic lytic lesions should be considered. Osteomyelitis tends to be locally aggressive and may mimic malignancy, in which cases, the clinical history can be the key to diagnosis. Vascular (sickle cell disease) and tumoral (aneurismal bone cyst, eosinophilic granuloma, metastases) lesions are relatively rare lesions but should be considered in the differential diagnosis, in the presence of certain imaging findings. The main difficulty is the differentiation between the benign and malignant nature; therefore, the main objective of this pictorial essay is to review the main skull lytic lesions found in pediatric age, describing the main findings in different imaging modalities (CT and MRI), allowing the neuroradiologist greater confidence in establishing the differential diagnosis, through a systematic and simple characterization of the lesions.

The Crosstalk Between Immune Cells After Intracerebral Hemorrhage.

The inflammatory mechanism of intracerebral hemorrhage (ICH) has been widely studied, and it is believed that the regulation of this mechanism is of great significance to the prognosis. In the early stage of the acute phase of ICH, the release of a large number of inflammatory factors around the hematoma can recruit more inflammatory cells to infiltrate the area, further release inflammatory factors, cause an inflammatory cascade reaction, aggravate the volume of cerebral hematoma and edema and further destroy the blood-brain barrier (BBB), according to this, the crosstalk between cells may be of great significance in secondary brain injury (SBI). Because most of the cells recruited are inflammatory immune cells, this paper mainly discusses the cells based on the inflammatory mechanism to discuss their functions after ICH, we found that among the main cells inherent in the brain, glial cells account for the majority, of which microglia are the most widely studied and it can interact with a variety of cells, which is reflected in the literature researches on its pathogenesis and treatment. We believe that exploring multi-mechanism and multi-cell regulated drugs may be the future development trend, and the existing research, the comparison and unification of modeling methods, and the observation of long-term efficacy may be the first problem that researchers need to solve.

Therapeutic effect of allicin in a mouse model of intracerebral hemorrhage.

Natural compounds with sulfur moiety produce various biological actions that may be beneficial for the therapies of several devastative disorders of the central nervous system. Here we investigated potential therapeutic effect of allicin, an organosulfur compound derived from garlic, in a mouse model of intracerebral hemorrhage (ICH) based on intrastriatal collagenase injection. Daily intraperitoneal administration of allicin (50 mg/kg) from 3 h after induction of ICH afforded neuroprotective effects, as evidenced by the increase of surviving neurons in the hematoma, reduction of axonal transport impairment, and prevention of axon tract injury. In addition, allicin inhibited accumulation of activated microglia/macrophages around the hematoma and infiltration of neutrophils within the hematoma. Allicin also suppressed ICH-induced mRNA upregulation of pro-inflammatory factors such as interleukin 6 and C-X-C motif ligand 2 in the brain, suggesting its anti-inflammatory effect. Moreover, ICH-induced increase of malondialdehyde as well as decrease of total glutathione in the brain was attenuated by allicin. Finally, allicin-treated mice showed better recovery of sensorimotor functions after ICH than vehicle-treated mice. These results indicate that allicin produces a therapeutic effect on ICH pathology via alleviation of neuronal damage, inflammatory responses and oxidative stress in the brain.

A destructive sinonasal organizing hematoma mimicking malignancy.

Sinonasal organizing hematomas (SOH) are rare, benign lesions that can be mistaken for malignancies due to their unfamiliarity among clinicians and aggressive appearance on imaging, which can lead to aggressive and unnecessary therapeutic interventions. Herein, we report an unusual case of SOH in an 87-year-old female patient who sought care at a maxillofacial surgery service due to persistent right nasal obstruction and imaging findings that suggested the possibility of sinonasal malignancy. We highlight the importance of recognizing these lesions to ensure adequate treatment through a conservative approach.

Myosin heavy chain 2 (MYH2) expression in hypertrophic chondrocytes of soft callus provokes endochondral bone formation in fracture.

AIMS: Muscle-bone interactions during fracture healing are rarely known. Here we investigated the presence and significance of myosin heavy chain 2 (MYH2), a component of myosin derived from muscles, in fracture healing. MAIN METHODS: We collected five hematoma and seven soft callus tissues from patients with distal radius fractures patients, randomly selected three of them, and performed a liquid chromatography-mass spectrometry (LC-MS) proteomics analysis. Proteomic results were validated by histological observation, immunohistochemistry, and immunofluorescence for MYH2 expression. These findings were further confirmed in a murine femoral fracture model in vivo and investigated using various methods in vitro. KEY FINDINGS: The LC-MS proteomics analysis showed that MYH proteins were enriched in human soft calluses compared to hematoma. Notably, MYH2 protein is upregulated as high rank in each soft callus. The histological examination showed that MYH2 expression was elevated in hypertrophic chondrocytes within the human soft callus. Consistent with human data, Myh2 were significantly co-localized with Sox9 in hypertrophic chondrocytes of murine femoral fracture, in comparison to pre-hypertrophic and proliferating chondrocytes. Soluble MYH2 protein treatment increased MMP13 and RUNX2 expression in chondrocytes. In soluble MYH2 treatment, proliferation of chondrocytes was not altered, but the osteogenic and chondrogenic features of chondrocytes increased and decreased during differentiation, respectively. SIGNIFICANCE: These findings indicate the potential of soluble MYH2 protein as a promising therapeutic strategy for promoting endochondral bone formation in chondrocytes following fracture.

CD22 blockade modulates microglia activity to suppress neuroinflammation following intracerebral hemorrhage.

Microglia are first responders to acute brain insults and initiate neuroinflammation to drive secondary tissue injury. Yet the key molecular switches in control of the inflammatory activity of microglia remain poorly understood. Intracerebral hemorrhage (ICH) is a devastating stroke subtype whereby a hematoma is formed within the brain parenchyma and associated with high mortality. Using a mouse model of ICH, we found upregulation of CD22 that predominantly occurred in microglia. Antibody blockade of CD22 led to a reduction in neurological deficits, brain lesion and hematoma volume. This was accompanied by reduced inflammatory activity, increased expression of alternative activation markers (CD206 and IL-10) and enhanced phagocytosis activity in microglia after ICH. CD22 blockade also led to an increase of phosphorylated SYK and AKT after ICH. Notably, the benefits of CD22 blockade were ablated in ICH mice subjected to microglial depletion with a colony-stimulating factor 1 receptor inhibitor PLX5622. Additionally, the protective effects of CD22 blockade was diminished in ICH mice receiving a SYK inhibitor R406. Together, our findings highlight CD22 as a key molecular switch to control the detrimental effects of microglia after acute brain injury, and provide a novel strategy to improve the outcome of ICH injury.

Hematomyelia associated with coronavirus disease 2019: A rare case report.

RATIONALE: Coronavirus disease 2019 (COVID-19) can damage the central nervous system. Although there have been reports of cerebral hemorrhage and infarction caused by COVID-19, hematomyelia due to COVID-19 has never been reported. PATIENT CONCERNS: A 40-year-old male was admitted to the hospital with positive nucleic acid detection for COVID-19 after experiencing fever for 2 weeks, urinary retention, fecal retention, and pain in both lower extremities for a week. DIAGNOSES: The patient diagnosis was established using thoracic and lumbar magnetic resonance imaging (MRI). Contrast-enhanced thoracic and lumbar MRI revealed subdural (dorsal predominant) short T1 and slightly long T2 bands in the T12-S2 infundibular canal in the scan field, and the subdural hematoma was yet to be distinguished from other diseases. Spinal cord edema was observed in the left vertebral plate and facet joint of the T11 vertebral body, indicative of inflammation. The cerebrospinal fluid (CSF) was positive for COVID-19 nucleic acid. INTERVENTIONS: Antiinfection, immunomodulation, correction of acid-base balance and electrolyte disorders, improvement of circulation, nerve nutrition, and other symptomatic supportive treatments were administered to the patient. OUTCOMES: The patient symptoms significantly improved after 4 weeks of anti-infection and immunomodulatory therapy. Repeat thoracolumbar MRI revealed absorption of the spinal cord hematoma, and the patient was discharged from the hospital. To date, COVID-19-related hematomyelia has not been reported and anti-infective and immunomodulatory therapies may be effective. LESSONS: COVID-19 not only easily leads to brain injury but can also cause spinal cord injury and even spinal cord hemorrhage. When patients with COVID-19 experience symptoms and signs of spinal cord injury, spinal cord injury and bleeding caused by COVID-19 should be considered, and MRI and lumbar puncture should be performed as soon as possible to make a clear diagnosis.

Spatiotemporal Cofilin Signaling, Microglial Activation, Neuroinflammation, and Cognitive Impairment Following Hemorrhagic Brain Injury.

Intracerebral hemorrhage (ICH) is a significant health concern associated with high mortality. Cofilin plays a crucial role in stress conditions, but its signaling following ICH in a longitudinal study is yet to be ascertained. In the present study, we examined the cofilin expression in human ICH autopsy brains. Then, the spatiotemporal cofilin signaling, microglia activation, and neurobehavioral outcomes were investigated in a mouse model of ICH. Human autopsy brain sections from ICH patients showed increased intracellular cofilin localization within microglia in the perihematomal area, possibly associated with microglial activation and morphological changes. Various cohorts of mice were subjected to intrastriatal collagenase injection and sacrificed at time points of 1, 3, 7, 14, 21, and 28 days. Mice suffered from severe neurobehavioral deficits after ICH, lasting for 7 days, followed by a gradual improvement. Mice suffered post-stroke cognitive impairment (PSCI) both acutely and in the chronic phase. Hematoma volume increased from day 1 to 3, whereas ventricle size increased from day 21 to 28. Cofilin protein expression increased in the ipsilateral striatum on days 1 and 3 and then decreased from days 7 to 28. An increase in activated microglia was observed around the hematoma on days 1 to 7, followed by a gradual reduction up to day 28. Around the hematoma, activated microglia showed morphological changes from ramified to amoeboid. mRNA levels of inflammatory [tumor necrosis factor-α (TNF-α), interleukin 1ß (IL-1ß), and interleukin-6 (IL-6) and anti-inflammatory markers [interleukin-10 (IL-10), transforming growth factor-ß TGF-ß, and arginase I (Arg1)] increased during the acute phase and decreased in the chronic phase. Blood cofilin levels increased on day 3 and matched the increase in chemokine levels. slingshot protein phosphatase 1 (SSH1) protein, which activates cofilin, was increased from day 1 to 7. These results suggest that microglial activation might be the sequel of cofilin overactivation following ICH, leading to widespread neuroinflammation and consequent PSCI.