Development and Validation of CXCR4 Nomogram-Based Immune Infiltration/Tumor Inflammation in Primary Glioblastoma.

Glioblastoma (GBM) is a highly malignant and aggressive tumor with poor prognosis. Therefore, the discovery of new prognostic molecular markers is of great significance for clinical prognosis. The CXC chemokine receptor (CXCR) members play a key regulatory role in many cancers. In this study, we explore the clinical value and application of the CXCR members in primary glioblastoma. Two GBM datasets from The Cancer Genome Atlas (TCGA) and The China Glioma Genome Atlas (CGGA) databases were used to explore the relationship between differential expression of CXCRs and GBM subtypes as well as immune infiltration. C-X-C motif chemokine receptor 4 (CXCR4) was screened as an independent prognostic factor, and a nomogram and risk prediction model were developed and tested in the CGGA database using the TCGA database. Receiver operating curve (ROC) and decision curve analysis (DCA) found good accuracy and net benefit of the models. The correlation of CXCR4 with immune infiltration and tumor was analyzed using CancerSEA and TIMER. In in vitro experiments, we found that CXCR4 was significantly overexpressed in glioblastoma and was closely related to the inflammatory response of U251/U87 cells. CXCR4 is an excellent independent prognostic factor for glioblastoma and positively correlates with tumor inflammation.

Long-term survival of patients with intracranial metastases from thyroid cancer presenting with seizures: a case report and literature review.

Background: Thyroid cancer has low incidence and mortality. While metastatic cancer is the most common type of intracranial cancer, patients with intracranial metastases from thyroid cancer very rarely present with seizures. Here, we describe a case study and review the neurological symptoms and histopathology of intracranial metastases from thyroid cancer. Case Description: A 38-year-old woman was diagnosed with intracranial metastases from papillary thyroid cancer, with the chief symptom being generalized seizures. The bilateral frontal masses were completely resected in 2 operations, after which the patient was treated with whole-brain radiotherapy and tyrosine kinase inhibitors (TKIs). It has now been over 13 years since thyroid cancer resection and 51 months since she was diagnosed with intracranial metastases from papillary thyroid cancer. The long-term survival might be due to the effective and prompt treatment. Through literature review, we found the incidence of intracranial metastases from different subtypes of thyroid cancer to be inconsistent with epidemiological findings in thyroid cancer. Conclusions: Intracranial metastases of thyroid cancer should be considered when the patient has a history of thyroid cancer with seizures. A combination of surgery, radiation therapy, and TKI drugs may prolong survival.

Remote ischemic postconditioning ameliorates stroke injury via the SDF-1α/CXCR4 signaling axis in rats.

Remote Ischemic Postconditioning (RIPostC) has become a research hotspot due to its protective effect on the brain in clinical studies related to ischemic stroke. The purpose of this study is to investigate the protective effect of RIPostC after ischemic stroke in rats. The middle cerebral artery occlusion/reperfusion (MCAO/R) model was established by the wire embolization method. RIPostC was obtained by inducing temporary ischemia in the hind limbs of rats. First, based on the results of short-term behavioral measures and long-term neurological function experiments, RIPostC was found to have a protective effect on the MCAO/R model and to improve neurological recovery in rats. Compared to the sham group, RIPostC upregulated the expression levels of C-X-C motif chemokine receptor 4(CXCR4) in the brain and stromal cell-derived factor-1(SDF-1α) in peripheral blood. In addition, RIPostC upregulated CXCR4 expression on CD34 + stem cells in peripheral blood in flow cytometric assays. Meanwhile, according to the results of EdU/DCX co-staining and CD31 staining, it was found that the effect of RIPostC on ameliorating brain injury via SDF-1α/CXCR4 signaling axis may be associated with vascular neogenesis. Finally, after inhibiting the SDF-1α/CXCR4 signaling axis using AMD3100(Plerixafor), we found that the neuroprotective effect of RIPostC was diminished. Taken together, RIPostC can improve neurobehavioral damage induced by MCAO/R in rats, and its mechanism may be related to SDF-1α/CXCR4 signaling axis. Therefore, RIPostC can be used as an intervention strategy for stroke. SDF-1α/CXCR4 signaling axis can also be a potential target for intervention.

Transient Receptor Potential Mucolipin-1 Participates in Intracerebral Hemorrhage-Induced Secondary Brain Injury by Inducing Neuroinflammation and Neuronal Cell Death.

Transient receptor potential mucolipin-1 (TRPML1) is the most abundantly and widely expressed channel protein in the TRP family. While numerous studies have been conducted involving many aspects of TRPML1, such as its role in cell biology, oncology, and neurodegenerative diseases, there are limited reports about what role it plays in intracerebral hemorrhage (ICH)-induced secondary brain injury (SBI). Here we examined the function of TRPML1 in ICH-induced SBI. The caudal arterial blood of rats was injected into the caudate nucleus of basal ganglia to establish an experimental ICH model. We observed that lentivirus downregulated the expression level of TRPML1 and chemical agonist promoted the enzyme activity of TRPML1. The results indicated that the protein levels of TRPML1 in brain tissues increased 24 h after ICH. These results suggested that downregulated TRPML1 could significantly reduce inflammatory cytokines, and ICH induced the production of LDH and ROS. Furthermore, TRPML1 knockout relieved ICH-induced neuronal cell death and degeneration, and declines in learning and memory after ICH could be improved by downregulating the expression of TRPML1. In addition, chemical agonist-expressed TRPML1 showed the opposite effect and exacerbated SBI after ICH. In summary, this study demonstrated that TRPML1 contributed to brain injury after ICH, and downregulating TRPML1 could improve ICH-induced SBI, suggesting a potential target for ICH therapy.

Oestrogen ameliorates blood-brain barrier damage after experimental subarachnoid haemorrhage via the SHH pathway in male rats.

BACKGROUND: Sex differences affect the occurrence, progression and regression of subarachnoid haemorrhage (SAH). Oestrogen plays a protective role in alleviating the vasospasm and neuronal apoptosis induced by SAH. However, whether oestrogen affects blood‒brain barrier (BBB) integrity has not been fully studied. Oestrogen has been found to regulate the sonic hedgehog (SHH) signalling pathway through the oestrogen receptor in gastric cancer and adrenal glands, and the SHH signalling pathway has an important role in maintaining the BBB by upregulating the expression of tight junction proteins. In this study, we investigated the relationship between oestrogen and the SHH signalling pathway using clinical data and established an experimental SAH model to explore whether oestrogen could ameliorate BBB damage after SAH through the SHH pathway. METHODS: Correlations between oestrogen and the SHH pathway were analysed by patients' cerebrospinal fluid (CSF) samples and the Genotype-Tissue Expression database (GTEx). Then, an experimental rat SAH model was established using the endovascular perforation method and treated with oestrogen, oestrogen inhibitors and SHH signalling pathway inhibitors. Then, the effects of oestrogen on BBB damage were analysed by western blot, immunofluorescence and neurobehavioural experiments. RESULTS: ESLIA detection and correlation analysis showed that oestrogen levels in patients' CSF were positively correlated with the SHH pathway, which was further verified by GTEx gene-correlation analysis. SHH was found to be mainly expressed in neurons and astrocytes in rats under physiological conditions and was upregulated by oestrogen pretreatment. In the SAH model, oestrogen pretreatment was found to reverse SAH-induced decreases in the SHH pathway, which were counteracted by oestrogen receptor inhibitors. Furthermore, oestrogen pretreatment reduced SAH-induced BBB damage, brain oedema and neurological dysfunction, which were eliminated by SHH pathway inhibitors. CONCLUSION: In conclusion, we demonstrate here that oestrogen pretreatment ameliorates brain injury after SAH, at least in part through SHH pathway-mediated BBB protection.

Efficacy and Safety of Different Bioactive Coils in Intracranial Aneurysm Interventional Treatment, a Systematic Review and Bayesian Network Meta-Analysis.

BACKGROUND: Bioactive coils have been used for nearly 20 years to improve aneurysm treatments. Previous studies are inadequate for comparing the efficacy and safety between different coils. The aim of this study was to investigate the safety and efficacy of different coils by comparing the percentage of people with different modified Raymond scale grades, re-rupture rates, and mortality in patients with intracranial aneurysms embolized with different coils. METHOD: Randomized controlled trials (RCTs) containing coils for aneurysm interventional treatment were collected from Web of Science, PubMed, and the Cochrane Library up to December 2021. Bayesian network meta-analysis with a randomized or fixed model was performed to compare the efficacy and safety among different bioactive coils and bare platinum coils. RESULTS: We pooled 3362 patients from eight RCTs. No significant differences were found between coils in the proportion of patients with a three-grade classification assessed with the modified Raymond scale immediately after surgery. Hydrogel coils did not show a significant difference in the percentage of patients with a modified Raymond scale grade I postoperatively compared with bare platinum coils (OR, -0.1080; 95% CI, -0.4201-0.2423), but at follow-up, the percentage of patients with modified Raymond scale grade I was significantly higher with hydrogel coils than with bare platinum coils (OR, 0.4957; 95% CI, 0.0060-0.9442). There were no statistical differences between these four coils in terms of aneurysm rupture or re-rupture rate and mortality. CONCLUSION: Though there was no significant difference in the embolization effect between the several coils in the postoperative period, complete embolization was more likely to be achieved with hydrogel coils compared to bare platinum coils at follow-up. There were no significant differences in safety between the several coil materials.

Intraoperative indocyanine green video angiography (ICG-VA) with FLOW 800 software in complex intracranial aneurysm surgery.

BACKGROUND: Indocyanine green video angiography (ICG-VA) is a safe and effective instrument to assess changes in cerebral blood flow during cerebrovascular surgery. After ICG-VA, FLOW 800 provides a color-coded map to directly observe the dynamic distribution of blood flow and to calculate semiquantitative blood flow parameters later. The purpose of our study is to assess whether FLOW 800 is useful for surgery of complex intracranial aneurysms and to provide reliable evidence for intraoperative decision-making. METHODS: We retrospectively reviewed patients with complex aneurysms that underwent microsurgical and intraoperative evaluation of ICG-VA and FLOW 800 color-coded maps from February 2019 to May 2020. FLOW 800 data were correlated with patient characteristics, clinical outcomes, and intraoperative decision-making. RESULTS: The study included 32 patients with 42 complex aneurysms. All patients underwent ICG-VA FLOW 800 data provided semiquantitative data regarding localization, flow status in major feeding arteries; color maps confirmed relative adequate flow in parent, branching, and bypass vessels. CONCLUSIONS: FLOW 800 is a useful supplement to ICG-VA for intraoperative cerebral blood flow assessment. ICG-VA and FLOW 800 can help to determine the blood flow status of the parent artery after aneurysm clipping and the bypass vessels after aneurysm bypass surgery.

A new scoring system for predicting extent of resection in medial sphenoid wing meningiomas based on three-dimensional multimodality fusion imaging.

BACKGROUND: Three-dimensional (3D) fusion imaging has been proved to be a promising neurosurgical tool for presurgical evaluation of tumor removal. We aim to develop a scoring system based on this new tool to predict the resection grade of medial sphenoid wing meningiomas (mSWM) intuitively. METHODS: We included 46 patients treated for mSWM from 2014 to 2019 to evaluate their tumors' location, volume, cavernous sinus involvement, vascular encasement, and bone invasion by 3D multimodality fusion imaging. A scoring system based on the significant parameters detected by statistical analysis was created and evaluated. RESULTS: The tumor volumes ranged from 0.8 cm3 to 171.9 cm3. A total of 39 (84.8%) patients had arterial involvement. Cavernous sinus (CS) involvement was observed in 23 patients (50.0%) and bone invasion was noted in 10 patients (21.7%). Simpson I resection was achieved in 10 patients (21.7%) and Simpson II resection was achieved in 17 patients (37.0%). Fifteen patients (32.6%) underwent Simpson III resection and 4 patients (8.7%) underwent Simpson IV resections. A scoring system was created. The score ranged from 1 to 10 and the mean score of our patients was 5.3 ± 2.8. Strong positive monotonic correlation existed between the score and resection grade (Rs = 0.772, P < 0.001). The scoring system had good predictive capacity with an accuracy of 69.60%. CONCLUSIONS: We described a scoring system that enabled neurosurgeons to predict extent of resection and outcomes for mSWM preoperatively with 3D multimodality fusion imaging. TRIAL REGISTRATION: Retrospectively registered.

Macrophage stimulating protein preserves blood brain barrier integrity after intracerebral hemorrhage through recepteur d'origine nantais dependent GAB1/Src/ß-catenin pathway activation in a mouse model.

Blood brain barrier (BBB) disruption is an important contributor to brain edema and neurological deficits following intracerebral hemorrhage (ICH). Macrophage stimulating protein (MSP) is a hepatocyte growth factor-like protein that mediates its functions via activating receptor tyrosine kinase recepteur d'origine nantais (RON). Grb2-associated binder 1 (GAB1) is a docking protein that mediates downstream receptor signal transduction pathways. This study aimed to evaluate the role of MSP and RON activated signaling pathway in preserving BBB integrity after collagenase-induced ICH. ICH mice received recombinant human MSP (rhMSP) or rhMSP combined with siRNA knockdown of RON or GAB1. rhMSP was administered by intranasal route 1 h after ICH. Brain edema, neurobehavior, BBB tight junction protein expression, and BBB permeability were evaluated. The expression of endogenous MSP and p-RON was decreased after ICH. Exogenous rhMSP administration reduced brain edema, neurological deficits, BBB permeability, and increased the expression of tight junction proteins in ICH mice. rhMSP administration increased the expression of p-RON, p-GAB1, p-Src, nuclear ß-catenin, and tight junction proteins after ICH. These effects were reversed with RON and GAB1 siRNA. We conclude that MSP activation of RON preserved BBB integrity via GAB-1/Src/ß-catenin pathway, thereby reducing brain edema and neurological deficits after ICH in mice.

Comparative analysis on microsurgical removal of craniopharyngioma via lateral supraorbital approach and standard pterional approach.

BACKGROUND: Craniopharyngioma is a kind of intracranial benign tumor that is primarily treated with surgery. At present, a variety of surgical approaches are used for tumor resection. We have conducted a comparative analysis of the two approaches most used in our department. METHODS: The study retrospectively analyzed the clinical data from 65 patients with craniopharyngioma surgically treated by the two approaches mentioned above. Among these patients, 24 were treated by lateral supraorbital (LSO) approach and 41 by standard pterional approach. Indicators including, but not limited to, length of incision, operation time, postoperative pituitary function, urine volume, visual function improvement, and hospitalization were used to compare these two groups of patients. RESULTS: The data shows that there was no significant difference in total tumor resection rate (P = 0.54), postoperative visual field improvement (P = 0.68) and postoperative function of endocrine. However, the LSO approach significantly reduced the operative incision (P = 0.001), shortened the operation time (P = 0.001) and operative complexity, while reducing the incidence of postoperative complications (P = 0.04). CONCLUSIONS: In surgical treatment of craniopharyngioma, LSO approach has similar surgical effect with standard pterional approach, but it can significantly shorten the operation time, reduce surgical trauma and the incidence of complications. Therefore, LSO provides another alternative to surgical approach for microsurgical removal of craniopharyngioma.

Potential dual role of nuclear factor-kappa B in experimental subarachnoid hemorrhage-induced early brain injury in rabbits.

OBJECTIVE AND DESIGN: Nuclear factor-kappa B (NF-κB) has multiple physiological and pathological functions. The role of NF-κB can be protective or destructive. We aim to investigate the biphasic activation of NF-κB in brain after subarachnoid hemorrhage (SAH). MATERIAL OR SUBJECTS: Eighty male New Zealand rabbits are assigned to control, SAH, vehicle, and pyrrolidine dithiocarbamate (PDTC) groups. TREATMENT: PDTC (3 mg/kg, dissolved in saline) was injected into cisterna magna. METHODS: Immunofluorescence and electrophoretic mobility shift assay experiments were performed to assess the activation of NF-κB. The levels of inflammatory and apoptosis mediators were detected by ELISA and real-time polymerase chain reaction. Nissl and immunofluorescent stain was performed to evaluate neuron injury. RESULTS: NF-κB activity in the brain cortex showed two peaks after SAH. Inflammatory mediators exhibited similar time course. PDTC could significantly inhibit the NF-κB activity and inflammatory mediators. Suppressing the early NF-κB activity significantly decreased neuron injury, while inhibiting the late one could statistically increase neuron injury. CONCLUSIONS: The biphasic NF-κB activation in the brain cortex after SAH played a decisive role on neuronal fate through the inflammatory signaling pathway. The early NF-κB activity contributed to neuron damage after SAH. Nevertheless, the late activated NF-κB may serve as a protector.

Quantitative anatomic comparison of the extended pterional transtemporal transtentorial approach and the subtemporal transtentorial approach to the petroclival region.

AIM: The anatomic characters and applicability of the extended pterional transtemporal transtentorial (EPTT) approach versus the subtemporal transtentorial (ST) approach for surgical treatment of petroclival tumors were evaluated. MATERIAL AND METHODS: Ten sides from five adult Chinese injected cadavers were manipulated using both two approaches. Four deep bony anatomic landmarks were specified in the skull base to create two adjoining triangles that were respectively located in the anterior and posterior petroclival region. The real, projected area and the percentage of the projected area were determined and calculated to compare the deep exposure from the two approaches. RESULTS: There was no difference regarding the percentage of the projected area was calculated in the anterior triangles (EPTT, 21.5±12.5%; ST, 28.8±14.9%; p=0.1948), but a significant difference was present in the posterior triangles (EPTT, 74.0±4.5%; ST, 51.5±4.3%; p < 0.01). Compared with the ST approach, the EPTT approach provides an equivalent percentage of projected area in the middle cranial fossa and a wider exposed area in the posterior cranial fossa. CONCLUSION: Through anatomic comparative analysis the EPTT approach provides better exposure and is more appropriate than the ST approach for large and giant petroclival tumors predominantly in the posterior cranial fossa with extensive invasion to parasellar structures and the cavernous sinus.

Dimethylfumarate alleviates early brain injury and secondary cognitive deficits after experimental subarachnoid hemorrhage via activation of Keap1-Nrf2-ARE system.

OBJECT: Oxidative stress and the inflammatory response are thought to promote brain damage in the setting of subarachnoid hemorrhage (SAH). Previous reports have shown that dimethylfumarate (DMF) can activate the Kelch-like ECH-associated protein 1-nuclear factor erythroid 2-related factor 2-antioxidant-responsive element (Keap1-Nrf2-ARE) system in vivo and in vitro, which leads to the downregulation of oxidative stress and inflammation. The aim of this study was to evaluate the potential neuroprotective effect of DMF on SAH-induced brain injury in rats. METHODS: Rats were subjected to SAH by the injection of 300 µl of autologous blood into the chiasmatic cistern. Rats in a DMF-treated group were given 15 mg/kg DMF twice daily by oral gavage for 2 days after the onset of SAH. Cortical apoptosis, neural necrosis, brain edema, blood-brain barrier impairment, learning deficits, and changes in the Keap1-Nrf2-ARE pathway were assessed. RESULTS: Administration of DMF significantly ameliorated the early brain injury and learning deficits induced by SAH in this animal model. Treatment with DMF markedly upregulated the expressions of agents related to Keap1-Nrf2-ARE signaling after SAH. The inflammatory response and oxidative stress were downregulated by DMF therapy. CONCLUSIONS: DMF administration resulted in abatement of the development of early brain injury and cognitive dysfunction in this prechiasmatic cistern SAH model. This result was probably mediated by the effect of DMF on the Keap1-Nrf2-ARE system.

The Neuroprotection of Lysosomotropic Agents in Experimental Subarachnoid Hemorrhage Probably Involving the Apoptosis Pathway Triggering by Cathepsins via Chelating Intralysosomal Iron.

α-Lipoic acid-plus (LAP), an amine derivative of α-lipoic acid (LA), could protect cells against oxidant challenges via chelating intralysosomal iron. However, the application of LAP in experimental subarachnoid hemorrhage (SAH) is still not well known. This study was designed to evaluate the potential neuroprotection of LAP on the early brain injury (EBI) and the underlying mechanisms in a rat model of SAH. The SAH models were induced in Sprague-Dawley rats. LA and LAP were oral administration and lasted for 72 h once a day. The brain tissue samples were obtained for assay at 72 h after SAH. In experiment 1, we found that lysosome amounts in neurons decreased significantly in SAH group, and LAP (100 mg/kg) could stabilize lysosomal membrane markedly based on lysosomal-associated membrane protein-1 (LAMP-1) expression in neurons by immunofluorescence. Hence, the LAP dosages of 100 and 150 mg/kg were applied in experiment 2. Firstly, Western blot analysis showed that the protein levels of cathepsin B/D, caspase-3, Bax, ferritin, and heme-oxygenase-1 (HO-1) markedly increased after SAH, which were further confirmed by double immunofluorescence staining and reversed by LA and LAP treatments. In addition, LA and LAP also reduced oxidative stress and iron deposition in brain tissue. Furthermore, LA and LAP significantly ameliorated brain edema, blood-brain barrier injury, cortical apoptosis, and neurological behavior impairment induced by SAH. Finally, it is noteworthy that LAP exerted more significant effects than LA on these parameters as described above. LAP probably exerted neuroprotective effects via targeting lysosomes and chelating intralysosomal iron in EBI post-SAH in rats.

Possible Role of Raf-1 Kinase in the Development of Cerebral Vasospasm and Early Brain Injury After Experimental Subarachnoid Hemorrhage in Rats.

This study aims to clarify the potential role of Raf-1 kinase in cerebral vasospasm (CVS) and early brain injury (EBI) after subarachnoid hemorrhage (SAH). Two experimental SAH models in rats, including cisterna magna double injection model for CVS study and prechiasmatic cistern single injection model for EBI study, were performed in this research. As a specific inhibitor of Raf-1, BAY 43-9006 was used in this study. In CVS study, time course study showed that the basilar artery exhibited vasospasm after SAH and became most severe at day 5, and the phosphorylation of Raf-1 had the same trends, while both vasospasm and the phosphorylation of Raf-1 induced by SAH were inhibited by BAY 43-9006 treatment. In addition, BAY 43-9006 treatment significantly reversed the phosphorylation of ERK1/2 and the activation of NF-κB induced by SAH and decreased the messenger RNA (mRNA) levels of IL-6 and IL-1ß. In EBI study, BAY 43-9006 treatment significantly suppressed the brain injury induced by SAH. Besides, BAY 43-9006 inhibited the phosphorylation of Raf-1 and ERK1/2; decreased the protein levels of COX-2, VEGF, and MMP-9; and reversed the activation of NF-κB induced by SAH. These results demonstrate that Raf-1 kinase contributes to CVS and EBI after SAH by enhancing the activation of the Raf-1/ERK1/2 and Raf-1/NF-κB signaling pathways, and that the inhibition of these pathways might offer new treatment strategies for CVS and EBI.

Elevated cerebral cortical CD24 levels in patients and mice with traumatic brain injury: a potential negative role in nuclear factor κb/inflammatory factor pathway.

Increasing evidence indicates that sterile inflammatory response contributes to secondary brain injury following traumatic brain injury (TBI). However, the specific mechanisms remain largely unknown, as is whether CD24, known as an important regulator in the non-infectious inflammatory response, plays a role in secondary brain injury after TBI. Here, the expression of CD24 was detected in samples from patients with TBI by quantitative real-time polymerase chain reaction (PCR), western blotting, immunohistochemistry and immunofluorescence. RNA interference was used to investigate the effects of CD24 on inflammatory response in a mouse model of TBI. Nuclear factor kappa B (NF-κB) DNA-binding activity was measured by electrophoretic mobility shift assay, and the levels of downstream pro-inflammatory cytokines tumor necrosis factor-α (TNF-α) and Interleukin 1ß (IL-1ß) were detected by real-time PCR. The results indicated that both the mRNA and protein levels of CD24 were markedly elevated after TBI in humans and mice, showing a time-dependent expression. The expression of CD24 could be observed in neurons, astrocytes and microglia in both humans and mice. Meanwhile, downregulation of CD24 significantly induced an increase of NF-κB DNA-binding activity and mRNA levels of TNF-α and IL-1ß. These findings indicated that CD24 expression could negatively regulate the NF-κB/inflammatory factor pathway after experimental TBI in mice, thus providing a novel target for therapeutic intervention of TBI.

Melatonin alleviates secondary brain damage and neurobehavioral dysfunction after experimental subarachnoid hemorrhage: possible involvement of TLR4-mediated inflammatory pathway.

Previous studies proved that melatonin protected against secondary brain damage by modulating oxidative stress after experimental subarachnoid hemorrhage (SAH), but it has not been evaluated yet about its effects on inflammatory pathway and secondary cognitive dysfunction in SAH model. This study was undertaken to evaluate the influence of melatonin on toll-like receptor 4 (TLR4) signaling pathway and neurobehavioral tests after SAH. Adult SD rats were divided into four groups: control group (n = 20), SAH group (n = 20), SAH+vehicle group (n = 20), and SAH+melatonin group (n = 20). The rat SAH model was induced by injection of 0.3 mL fresh arterial, nonheparinized blood into the prechiasmatic cistern in 20 s. In SAH+melatonin group, melatonin was administered i.p. at 150 mg/kg at 2 and 24 hr after the induction of SAH. Cognitive and memory changes were investigated in the Morris water maze. Treatment with melatonin markedly decreased the expressions of TLR4 pathway-related agents, such as high-mobility group box 1 (HMGB1), TLR4, nuclear factor-κB (NF-κB), myeloid differentiation factor 88 (MyD88), interleukin-1ß (IL-1ß), tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), and inducible nitric oxide synthase (iNOS). Administration of melatonin following SAH significantly ameliorated spatial learning and memory deficits in this prechiasmatic blood injection model. Staining of apoptosis and necrosis indicated that fewer positive cells appeared in melatonin-treated group than SAH+vehicle group. In conclusion, melatonin may attenuate neurobehavioral dysfunction in this SAH model, and melatonin exhibits neuroprotection possibly not only through anti-oxidative pathway but also anti-inflammatory signaling after experimental SAH.

Correlation of Nrf2 and HIF-1α in glioblastoma and their relationships to clinicopathologic features and survival.

OBJECTIVES: Glioblastoma (GB) is the most common, aggressive, and proliferative among all brain tumors. The prognosis of GB is still far from satisfactory currently, thus demanding great modification and enhancement, which may be acquired by the help of the molecular target therapy. Nuclear factor E2-related factor 2 (Nrf2), a pivotal transcriptional factor of cellular responses to oxidative stress, was observed to function remarkably in cancer pathobiology. In the current study, we analyzed the correlation between Nrf2 and Hypoxia-inducible factor-1alpha (HIF-1alpha) in GB, together with their association to the features and survival of clinicopathology. METHODS: We examined the expression of Nrf2 and HIF-1alpha in 68 specimens of GB by tissue microarray and immunohistochemistry, and correlated this investigation to the outcome of GB patients. RESULTS: Nrf2 and HIF-1alpha were overexpressed in GB tissues. There was significant correlation between the high level of Nrf2 and tumor necrosis on MRI and 1-year survival. There was significant correlation between HIF-1alpha level and Nrf2 status (r = 0·294, P = 0·015). Kaplan-Meier analysis showed that high Nrf2 expression was significantly associated with shorter overall survival (OS) (log-rank test, P = 0·006), and was identified as an independent prognostic factor in multivariate analysis (P = 0·034). HIF-1alpha was another independent factor for both OS and progression-free survival by Cox regression analysis (P = 0·048 and P = 0·032, respectively). DISCUSSION: Mutual association between Nrf2 and HIF-1alpha was found in GB: higher Nrf2 expression and poorer outcome of GB patients. Nrf2 would therefore be a new molecular marker for the targeted treatment of GB.

Knockdown of NF-E2-related factor 2 inhibits the proliferation and growth of U251MG human glioma cells in a mouse xenograft model.

NF-E2-related factor 2 (Nrf2) is a pivotal transcription factor of cellular responses to oxidative stress and recent evidence suggests that Nrf2 plays an important role in cancer pathobiology. However, the underlying mechanism has yet to be elucidated, particularly in glioma. In the present study, we investigated the role of Nrf2 in the clinical prognosis, cell proliferation and tumor growth of human glioblastoma multiforme (GBM). We detected overexpression of Nrf2 protein levels in GBM compared to normal brain tissues. Notably, higher protein levels of Nrf2 were significantly associated with poorer overall survival and 1-year survival for GBM patients. Furthermore, we constructed the plasmid Si-Nrf2 and transduced it into U251MG cells to downregulate the expression of Nrf2 and established stable Nrf2 knockdown cells. The downregulation of Nrf2 suppressed cell proliferation in vitro and tumor growth in mouse xenograft models. We performed immunohistochemistry staining to detect the protein levels of Nrf2, Ki-67, caspase-3 and CD31 in the xenograft tumors and found that the expression levels of Nrf2 and Ki-67 were much lower in the Si-Nrf2 group compared to the Si-control group. In addition, the number of caspase-3-positive cells was significantly increased in the Si-Nrf2 group. By analysis of microvessel density (MVD) assessed by CD31, the MVD value in the Si-Nrf2 group decreased significantly compared to the Si-control group. These findings indicate that the knockdown of Nrf2 may suppress tumor growth by inhibiting cell proliferation, increasing cell apoptosis and inhibiting angiogenesis. These results highlight the potential of Nrf2 as a candidate molecular target to control GBM cell proliferation and tumor growth.

Activation of nuclear factor-κB in the brain after experimental subarachnoid hemorrhage and its potential role in delayed brain injury.

It has been reported that inflammation is involved in brain injury after subarachnoid hemorrhage (SAH). Nuclear factor-κB (NF-κB) is a key transcriptional regulator of inflammatory genes. Here, we used pyrrolidine dithiocarbamate(PDTC), an inhibitor of NF-κB, through intracisternal injection to study the role of NF-κB in delayed brain injury after SAH. A total of 55 rabbits were randomly divided into five groups: the control group; the SAH groups including Day-3, 5, and 7 SAH groups (the rabbits in these groups were sacrificed at 3, 5, 7 days after SAH, respectively); and the PDTC group (n = 11 for each group). Electrophoretic mobility shift assay (EMSA) was performed to detect NF-κB DNA-binding activity. The mRNA levels of tumor necrosis factor (TNF)-α, interleukin (IL)-1ß, and intercellular adhesion molecule (ICAM)-1 were evaluated by RT-PCR analysis. Deoxyribonucleic acid fragmentation was detected by TUNEL and p65 immunoactivity was assessed by immunohistochemistry. Our results showed the activation of NF-κB after SAH, especially at day 3 and 5. The activated p65 was detected in neurons. NF-κB DNA-binding activity was suppressed by intracisternal administration of PDTC. Increased levels of the TNF-α, IL-1ß, and ICAM-1 mRNA were found in the brain at day 5 after SAH, and which were suppressed in the PDTC group. The number of TUNEL-positive cells also decreased significantly in the PDTC group compared with that in the Day-5 SAH group. These results demonstrated that the activated NF-κB in neurons after SAH plays an important role in regulating the expressions of inflammatory genes in the brain, and ultimately contributes to delayed brain injury.