TIMP1 protects against blood-brain barrier disruption after subarachnoid haemorrhage by inhibiting ubiquitination of astrocytic ß1-integrin.

BACKGROUND: Astrocytes regulate blood-brain barrier (BBB) integrity, whereas subarachnoid haemorrhage (SAH) results in astrocyte dysregulation and BBB disruption. Here, we explored the involvement of tissue inhibitor of matrix metalloprotease-1 (TIMP1) in astrocyte-mediated BBB protection during SAH, along with its underlying mechanisms. METHODS: C57BL/6J mice were used to establish a model of SAH. The effects of TIMP1 on SAH outcomes were analysed by intraperitoneal injection of recombinant mouse TIMP1 protein (rm-TIMP1; 250 µg/kg). The roles of TIMP1 and its effector ß1-integrin on astrocytes were observed by in vivo transduction with astrocyte-targeted adeno-associated virus carrying TIMP1 overexpression plasmid or ß1-integrin RNAi. The molecular mechanisms underlying TIMP1 and ß1-integrin interactions were explored in primary cultured astrocytes stimulated with red blood cells (RBCs). RESULTS: TIMP1 was upregulated after SAH. Administration of rm-TIMP1 mitigated SAH-induced early brain injury (EBI) in male and female mice. TIMP1 was primarily expressed in astrocytes; its overexpression in astrocytes led to increased ß1-integrin expression in astrocytes, along with the preservation of astrocytic endfoot attachment to the endothelium and subsequent recovery of endothelial tight junctions. All of these effects were reversed by the knockdown of ß1-integrin in astrocytes. Molecular analysis showed that TIMP1 overexpression decreased the RBC-induced ubiquitination of ß1-integrin; this effect was partially achieved by inhibiting the interaction between ß1-integrin and the E3 ubiquitin ligase Trim21. CONCLUSION: TIMP1 inhibits the interaction between ß1-integrin and Trim21 in astrocytes, thereby rescuing the ubiquitination of astrocytic ß1-integrin. It subsequently restores interactions between astrocytic endfeet and the endothelium, as well as BBB integrity, eventually mitigating SAH-induced EBI.

TRIM25 promotes glioblastoma cell growth and invasion via regulation of the PRMT1/c-MYC pathway by targeting the splicing factor NONO.

BACKGROUND: Ubiquitination plays an important role in proliferating and invasive characteristic of glioblastoma (GBM), similar to many other cancers. Tripartite motif 25 (TRIM25) is a member of the TRIM family of proteins, which are involved in tumorigenesis through substrate ubiquitination. METHODS: Difference in TRIM25 expression levels between nonneoplastic brain tissue samples and primary glioma samples was demonstrated using publicly available glioblastoma database, immunohistochemistry, and western blotting. TRIM25 knockdown GBM cell lines (LN229 and U251) and patient derived GBM stem-like cells (GSCs) GBM#021 were used to investigate the function of TRIM25 in vivo and in vitro. Co-immunoprecipitation (Co-IP) and mass spectrometry analysis were performed to identify NONO as a protein that interacts with TRIM25. The molecular mechanisms underlying the promotion of GBM development by TRIM25 through NONO were investigated by RNA-seq and validated by qRT-PCR and western blotting. RESULTS: We observed upregulation of TRIM25 in GBM, correlating with enhanced glioblastoma cell growth and invasion, both in vitro and in vivo. Subsequently, we screened a panel of proteins interacting with TRIM25; mass spectrometry and co-immunoprecipitation revealed that NONO was a potential substrate of TRIM25. TRIM25 knockdown reduced the K63-linked ubiquitination of NONO, thereby suppressing the splicing function of NONO. Dysfunctional NONO resulted in the retention of the second intron in the pre-mRNA of PRMT1, inhibiting the activation of the PRMT1/c-MYC pathway. CONCLUSIONS: Our study demonstrates that TRIM25 promotes glioblastoma cell growth and invasion by regulating the PRMT1/c-MYC pathway through mediation of the splicing factor NONO. Targeting the E3 ligase activity of TRIM25 or the complex interactions between TRIM25 and NONO may prove beneficial in the treatment of GBM.

Neutrophil-like pH-responsive pro-efferocytic nanoparticles improve neurological recovery by promoting erythrophagocytosis after intracerebral hemorrhage.

Rationale: Intracerebral hemorrhage (ICH) is a devastating cerebrovascular disease resulting from blood extravasating into the brain parenchyma. Escalation of erythrophagocytosis (a form of efferocytosis), avoiding the consequent release of the detrimental erythrocyte lysates, may be a promising target of ICH management. The ADAM17 inhibitor and liver X receptor (LXR) agonist could promote efficient efferocytosis and injury repair. Nevertheless, the poor bioavailability and restriction of the blood-brain barrier (BBB) hinder their application. Therefore, it is needed that biocompatible and smart nanoplatforms were designed and synthesized to realize effective therapy targeting erythrophagocytosis. Methods: We first assessed the synergistic effect of therapeutic GW280264X (an ADAM17 inhibitor) and desmosterol (an LXR agonist) on erythrophagocytosis in vitro. Then a pH-responsive neutrophil membrane-based nanoplatform (NPEOz) served as a carrier to accurately deliver therapeutic GW280264X and desmosterol to the damaged brain was prepared via co-extrusion. Afterwards, their pH-responsive performance was valued in vitro and targeting ability was assessed through fluorescence image in vivo. Finally, the pro-erythrophagocytic and anti-neuroinflammatory ability of the nanomedicine and related mechanisms were investigated. Results: After the synergistical effect of the above two drugs on erythrophagocytosis was confirmed, we successfully developed neutrophil-disguised pH-responsive nanoparticles to efficiently co-deliver them. The nanoparticles could responsively release therapeutic agents under acidic environments, and elicit favorable biocompatibility and ability of targeting injury sites. D&G@NPEOz nanoparticles enhanced erythrophagocytosis through inhibiting shedding of the efferocytotic receptors MERTK/AXL mediated by ADAM17 and accelerating ABCA-1/ABCG-1-mediated cholesterol efflux regulated by LXR respectively. In addition, the nano-formulation was able to modulate the inflammatory microenvironment by transforming efferocytes towards a therapeutic phenotype with reducing the release of proinflammatory cytokines while increasing the secretion of anti-inflammatory factors, and improve neurological function. Conclusions: This biomimetic nanomedicine is envisaged to offer an encouraging strategy to effectively promote hematoma and inflammation resolution, consequently alleviate ICH progression.

Lateralized response of skull bone marrow via osteopontin signaling in mice after ischemia reperfusion.

Skull bone marrow is thought to be an immune tissue closely associated with the central nervous system (CNS). Recent studies have focused on the role of skull bone marrow in central nervous system disorders. In this study, we performed single-cell RNA sequencing on ipsilateral and contralateral skull bone marrow cells after experimental stroke and then performed flow cytometry and analysis of cytokine expression. Skull marrow showed lateralization in response to stroke. Lateralization is demonstrated primarily by the proliferation and differentiation of myeloid and lymphoid lineage cells in the skull bone marrow adjacent to the ischemic region, with an increased proportion of neutrophils compared to monocytes. Analysis of chemokines in the skull revealed marked differences in chemotactic signals between the ipsilateral and contralateral skull, whereas sympathetic signals innervating the skull did not affect cranial bone marrow lateralization. Osteopontin (OPN) is involved in region-specific activation of the skull marrow that promotes inflammation in the meninges, and inhibition of OPN expression improves neurological function.

Ly6C-high monocytes alleviate brain injury in experimental subarachnoid hemorrhage in mice.

BACKGROUND: Subarachnoid hemorrhage (SAH) is an uncommon type of potentially fatal stroke. The pathophysiological mechanisms of brain injury remain unclear, which hinders the development of drugs for SAH. We aimed to investigate the pathophysiological mechanisms of SAH and to elucidate the cellular and molecular biological response to SAH-induced injury. METHODS: A cross-species (human and mouse) multiomics approach combining high-throughput data and bioinformatic analysis was used to explore the key pathophysiological processes and cells involved in SAH-induced brain injury. Patient data were collected from the hospital (n = 712). SAH was established in adult male mice via endovascular perforation, and flow cytometry, a bone marrow chimera model, qPCR, and microglial depletion experiments were conducted to explore the origin and chemotaxis mechanism of the immune cells. To investigate cell effects on SAH prognosis, murine neurological function was evaluated based on a modified Garcia score, pole test, and rotarod test. RESULTS: The bioinformatics analysis confirmed that inflammatory and immune responses were the key pathophysiological processes after SAH. Significant increases in the monocyte levels were observed in both the mouse brains and the peripheral blood of patients after SAH. Ly6C-high monocytes originated in the bone marrow, and the skull bone marrow contribute a higher proportion of these monocytes than neutrophils. The mRNA level of Ccl2 was significantly upregulated after SAH and was greater in CD11b-positive than CD11b-negative cells. Microglial depletion, microglial inhibition, and CCL2 blockade reduced the numbers of Ly6C-high monocytes after SAH. With CCR2 antagonization, the neurological function of the mice exhibited a slow recovery. Three days post-SAH, the monocyte-derived dendritic cell (moDC) population had a higher proportion of TNF-α-positive cells and a lower proportion of IL-10-positive cells than the macrophage population. The ratio of moDCs to macrophages was higher on day 3 than on day 5 post-SAH. CONCLUSIONS: Inflammatory and immune responses are significantly involved in SAH-induced brain injury. Ly6C-high monocytes derived from the bone marrow, including the skull bone marrow, infiltrated into mouse brains via CCL2 secreted from microglia. Moreover, Ly6C-high monocytes alleviated neurological dysfunction after SAH.

Risk of Death from Alzheimer's Disease Associated with Brain Tumor, Glioma, and Glioblastoma.

BACKGROUND: No study has compared the risk of Alzheimer's disease (AD) in patients with brain tumors, gliomas, or glioblastomas with the risk in patients with other tumors. OBJECTIVE: To determine whether, compared with other tumors, brain tumors, gliomas, and glioblastomas increase the risk of AD. METHODS: This study identified a case group of 24,441 patients from the Surveillance, Epidemiology, and End Results (SEER) database who were diagnosed with only one primary tumor at age > 20 years in 1975-2019 and died from AD at age > 65 years as case group. The control group comprised 122,205 subjects from the SEER database who died from causes other than AD but otherwise had the same conditions as those in the case group. RESULTS: There was a significantly lower prevalence of glioma (0.074% versus 0.14%, p = 0.007) and glioblastoma (0.0082% versus 0.074%, p = 0.001) in patients who died from AD than in those who died from other causes, while brain tumors were not significantly associated with AD death (p = 0.227). When adjusted for factors including age at death, sex, race, tumor behavior, radiation therapy and tumor-directed surgery, glioblastoma was related to a significantly lower AD risk than other tumors (odds ratio: 0.19, 95% CI: 0.05-0.77). Additionally, patients who were older, female, American Indian/Alaska Native, had a benign tumor, radiation therapy and tumor-directed surgery had a significantly higher risk of dying from AD. CONCLUSION: Gliomas and glioblastomas were associated with a significantly lower risk of death from AD than other tumors.

Current knowledge of thrombocytopenia in sepsis and COVID-19.

Thrombocytopenia, characterized by a decrease in platelet count, is commonly observed in sepsis and COVID-19. In sepsis, thrombocytopenia can result from various mechanisms, including impaired platelet production in the bone marrow, accelerated platelet destruction due to increased inflammation, sequestration of platelets in the spleen, immune-mediated platelet destruction, or dysregulated host responses. Similarly, thrombocytopenia has been reported in COVID-19 patients, but the immune-related mechanisms underlying this association remain unclear. Notably, interventions targeting thrombocytopenia have shown potential for improving outcomes in both sepsis and COVID-19 patients. Understanding these mechanisms is crucial for developing effective treatments.

Src inhibition rescues FUNDC1-mediated neuronal mitophagy in ischaemic stroke.

BACKGROUND: Ischaemic stroke triggers neuronal mitophagy, while the involvement of mitophagy receptors in ischaemia/reperfusion (I/R) injury-induced neuronal mitophagy remain not fully elucidated. Here, we aimed to investigate the involvement of mitophagy receptor FUN14 domain-containing 1 (FUNDC1) and its modulation in neuronal mitophagy induced by I/R injury. METHODS: Wild-type and FUNDC1 knockout mice were generated to establish models of neuronal I/R injury, including transient middle cerebral artery occlusion (tMCAO) in vivo and oxygen glucose deprivation/reperfusion in vitro. Stroke outcomes of mice with two genotypes were assessed. Neuronal mitophagy was analysed both in vivo and in vitro. Activities of FUNDC1 and its regulator Src were evaluated. The impact of Src on FUNDC1-mediated mitophagy was assessed through administration of Src antagonist PP1. RESULTS: To our surprise, FUNDC1 knockout mice subjected to tMCAO showed stroke outcomes comparable to those of their wild-type littermates. Although neuronal mitophagy could be activated by I/R injury, FUNDC1 deletion did not disrupt neuronal mitophagy. Transient activation of FUNDC1, represented by dephosphorylation of Tyr18, was detected in the early stages (within 3 hours) of neuronal I/R injury; however, phosphorylated Tyr18 reappeared and even surpassed baseline levels in later stages (after 6 hours), accompanied by a decrease in FUNDC1-light chain 3 interactions. Spontaneous inactivation of FUNDC1 was associated with Src activation, represented by phosphorylation of Tyr416, which changed in parallel with the level of phosphorylated FUNDC1 (Tyr18) during neuronal I/R injury. Finally, FUNDC1-mediated mitophagy in neurons under I/R conditions can be rescued by pharmacological inhibition of Src. CONCLUSIONS: FUNDC1 is inactivated by Src during the later stage (after 6 hours) of neuronal I/R injury, and rescue of FUNDC1-mediated mitophagy may serve as a potential therapeutic strategy for treating ischaemic stroke.

A Clinical Prediction Model Based on Post Large Artery Atherosclerosis Infarction Pneumonia.

BACKGROUND AND PURPOSE: Stroke-associated pneumonia (SAP) has been found as a common complication in acute ischemic stroke (AIS) patients. Large artery atherosclerosis (LAA) infarct is a major subtype of AIS. This study aimed to build a clinical prediction model for SAP of LAA type AIS patients. METHODS: This study included 295 patients with LAA type AIS. Univariate analyses and logistic regression analyses were conducted to determine the independent predictors for the modeling purpose. Nomogram used receiver operating characteristics to assess the accuracy of the model, and the calibration plots were employed to assess the fitting degree between the model and the practical scenario. One hundred and five patients were employed for the external validation to test the stability of the model. RESULTS: From the univariate analysis, patients' ages, neutrophil-to-lymphocyte ratios, National Institute of Health Stroke scale (NIHSS) scores, red blood cell, sex, history of coronary artery disease, stroke location and volume-viscosity swallow test showed statistical difference in the development group for the occurrence of SAP. By incorporating the factors above into a multivariate logistic regression analysis, patients' ages, neutrophil-to-lymphocyte ratios, NIHSS, and volume-viscosity swallow test emerged as the independent risk factors of the development of SAP. The nomogram based on the mentioned 4 variables above achieved a receiver operating characteristic of 0.951 and a validation group of 0.946. CONCLUSIONS: The proposed nomogram is capable of predicting predict the occurrence of SAP in LAA type AIS patients, and it may identify high-risk patients in time and present information for in-depth treatment.

Ginkgetin Promotes M2 Polarization of Microglia and Exert Neuroprotection in Ischemic Stroke via Modulation of PPARγ Pathway.

Neuroinflammation plays an important role in the pathophysiological process of acute cerebral infarction, which may aggravate brain injury and hinder neuro-repair. Microglia are innate immune cells in the brain. Ginkgetin has anti-inflammatory and neuroprotective effects, but the mechanism remains unclear. This study aims to explore the regulatory effects of ginkgetin on microglia polarization in brain ischemia. Oxygen glucose deprivation (OGD) cellular model and middle cerebral artery occlusion (MCAO) animal model was used in this study. We first observed the dynamic process of microglia polarization in ischemic stroke, and then investigated the effect of ginkgetin treatment on microglia polarization. Finally, we studied the role of PPARγ signaling pathway and the blocking effect of PPARγ antagonist GW9662 in this process. OGD and cerebral ischemia polarized microglia mainly to M1 type. However, ginkgetin treatment converted microglia from M1 type to M2 type, inhibited neuroinflammation, and exerted neuronal protective effects. PPARγ signaling pathway was activated during this process. The above effects could be blocked by GW9662. Ginkgetin can promote M2 polarization of microglia through PPARγ signaling pathway, thereby inhibiting neuroinflammation and promoting recovery of neurological functions in ischemic stroke.

Sex-Associated Differences in Neurovascular Dysfunction During Ischemic Stroke.

Neurovascular units (NVUs) are basic functional units in the central nervous system and include neurons, astrocytes and vascular compartments. Ischemic stroke triggers not only neuronal damage, but also dissonance of intercellular crosstalk within the NVU. Stroke is sexually dimorphic, but the sex-associated differences involved in stroke-induced neurovascular dysfunction are studied in a limited extend. Preclinical studies have found that in rodent models of stroke, females have less neuronal loss, stronger repairing potential of astrocytes and more stable vascular conjunction; these properties are highly related to the cerebroprotective effects of female hormones. However, in humans, these research findings may be applicable only to premenopausal stroke patients. Women who have had a stroke usually have poorer outcomes compared to men, and because stoke is age-related, hormone replacement therapy for postmenopausal women may exacerbate stroke symptoms, which contradicts the findings of most preclinical studies. This stark contrast between clinical and laboratory findings suggests that understanding of neurovascular differences between the sexes is limited. Actually, apart from gonadal hormones, differences in neuroinflammation as well as genetics and epigenetics promote the sexual dimorphism of NVU functions. In this review, we summarize the confirmed sex-associated differences in NVUs during ischemic stroke and the possible contributing mechanisms. We also describe the gap between clinical and preclinical studies in terms of sexual dimorphism.

Glutamate-Oxaloacetate Transaminase 1 Impairs Glycolysis by Interacting with Pyruvate Carboxylase and Further Inhibits the Malignant Phenotypes of Glioblastoma Cells.

BACKGROUND: Glycolysis is an important metabolic manner in glioblastoma multiforme (GBM)'s rapid growth. It has been reported that glutamate-oxaloacetate transaminase 1 (GOT1) is low-expressed in GBM and patients with high-expressed GOT1 have better prognosis. However, the effect and mechanism of GOT1 on glycolysis and malignant phenotypes of GBM cells are still unclear. METHODS: The expression differences of GOT1 between GBM parenchyma and adjacent tissues were detected. The prognosis and clinical data with different levels of GOT1 were also analyzed. The glucose consumption, production of lactate and pyruvate were measured after GOT1 was knocked down or overexpressed. The effects of GOT1 on GBM cell's malignant phenotypes were analyzed by Western blot, CCK-8 assay, and flow cytometry. The relationship between GOT1 and pyruvate carboxylase (PC) was examined by immunoprecipitation and immunofluorescence. RESULTS: GOT1 was expressed little in GBM, and patients with highly expressed GOT1 had longer survival periods. Overexpressed GOT1 inhibited the glycolysis and malignant phenotypes of GBM cells. 2-DG treatment could partially reverse the enhancement of malignant phenotypes caused by knockdown of GOT1. The expression of GOT1 was positively correlated with PC. The inhibitory effect of GOT1 on glycolysis could be partially reversed by PC's knockdown. CONCLUSIONS: GOT1 could impair glycolysis by interacting with PC and further inhibit the malignant phenotypes of GBM cells.

Tumor-derived exosomal long noncoding RNA LINC01133, regulated by Periostin, contributes to pancreatic ductal adenocarcinoma epithelial-mesenchymal transition through the Wnt/ß-catenin pathway by silencing AXIN2.

Pancreatic ductal adenocarcinoma (PDAC) is one of the most fatal malignancies and rapidly progressive diseases. Exosomes and long noncoding RNAs (lncRNAs) are emerging as vital mediators in tumor cells and their microenvironment. However, the detailed roles and mechanisms of exosomal lncRNAs in PDAC progression remain unknown. Here, we aimed to clarify the clinical significance and mechanisms of exosomal lncRNA 01133 (LINC01133) in PDAC. We analyzed the expression of LINC01133 in PDAC and found that exosomal LINC01133 expression was high and positively correlated with higher TNM stage and poor overall survival rate of PDAC patients. Further research demonstrated that Periostin could increase exosome secretion and then enhance LINC01133 expression. In addition, Periostin increased p-EGFR, p-Erk, and c-myc expression, and c-myc could bind to the LINC01133 promoter region. These findings suggested that LINC01133 can be regulated by Periostin via EGFR pathway activity. We also observed that LINC01133 promoted the proliferation, migration, invasion, and epithelial-mesenchymal transition (EMT) of pancreatic cancer cells. We subsequently evaluated the effect of LINC01133 on the Wnt/ß-catenin pathway and confirmed that LINC01133 can interact with Enhancer Of Zeste Homolog 2 (EZH2) and then promote H3K27 trimethylation. This can further silence AXIN2 and suppress GSK3 activity, ultimately activating ß-catenin. Collectively, these data indicate that exosomal LINC01133 plays an important role in pancreatic tumor progression, and targeting LINC01133 may provide a potential treatment strategy for PDAC.

Netrin-1 promotes retinoblastoma-associated angiogenesis.

BACKGROUND: Retinoblastoma (Rb) is the most common intraocular cancer of infancy and childhood, with an incidence of nearly 0.006% in all live births. Although a functional loss or inactivation of both alleles of the retinoblastoma 1 (RB1) gene during retinal development appears to be the predominant etiology for Rb, genes associated with tumor angiogenesis are also likely to be involved in the development of this condition. Netrin-1 is a factor that regulates pathological angiogenesis, while its role in Rb is largely unknown. The present study examined the role of netrin-1 in Rb. METHODS: The expression of netrin-1 in Rb was assessed using public databases and using clinical specimens by RT-qPCR for mRNA and by ELISA for protein. The expression of netrin-1 was suppressed in Rb by siRNA and the effects on cell growth were determined by a CCK-8 assay, while the effects on angiogenesis were examined in vitro using human umbilical vein endothelial cell (HUVEC) assays and in vivo by quantification of tumor vessel density. RESULTS: Analysis of published databases revealed that the netrin-1 gene is significantly upregulated in Rb, which was confirmed by immunohistochemistry on clinical specimens. Inhibition of netrin-1 in Rb cell lines significantly reduced their effects on angiogenesis in vitro using a HUVEC co-culture assay without affecting cell growth. Inhibition of netrin-1 expression in vivo suppressed the growth of grafted Rb, and this effect could be abolished by co-expression of vascular endothelial growth factor A (VEGF-A). CONCLUSIONS: This data demonstrated a novel role for netrin-1 in the regulation of Rb-associated cancer vascularization and may represent a novel therapeutic target for patients with Rb.

Prediction of CTNNB1 Mutation Status in Pediatric Cystic Adamantinomatous Craniopharyngioma by Using Preoperative Magnetic Resonance Imaging Manifestation.

OBJECTIVE: CTNNB1-targeted inhibitor is demonstrated to be an effective neoadjuvant therapy in adamantinomatous craniopharyngioma (ACP) patients and cystic degeneration is a canonical sign of pediatric ACP. This study aimed to investigate the relationship between the cystic performances and CTNNB1 mutation (CTNNB1 MUT) status so as to analyze the possible diagnostic criteria of CTNNB1 MUT in pediatric cystic ACP (PCACP). METHODS: Patient's population, clinical characteristics, tissue samples and MRI data were collected and summarized in PCACP patients. The results were compared between CTNNB1 MUT and CTNNB1 wild-type (WT) groups according to the Sanger sequencing. MRI features of the cyst were also recorded. The receiving operating characteristic (ROC) curve analysis was applied to evaluate the differential diagnostic value. RESULTS: 19 of the 61 patients manifested CTNNB1 MUT PCACP and 42 patients were CTNNB1 WT PCACP. Multiple cysts, irregular shape of cyst, hypo-intense interior signal of cyst on non-contrast T1W1, compression with optic chiasm and pituitary stalk and enhancement signal of cystic wall have been demonstrated in CTNNB1 MUT PCACP patients on MRI. Only the Area under the curve (AUC) values of quantity of cyst, shape of cyst and interior signal of cyst on non-contrast T1W1 were over 0.7. For criteria based on the combination of the 6 characteristic features, the AUC value was 0.928. CONCLUSION: Preoperative MRI may provide an effective value in predicting PCACP patients with CTNNB1 MUT and offer potential evidence for preoperative management with molecular targeted agents.

Evaluation of pre-operative neuroimaging characteristics in patients with primary hemifacial spasm as a prognostic factor of microvascular decompression.

OBJECTIVE: The aim of this study was to explore the possible pathogenesis of primary hemifacial spasm (HFS) according to the performances of preoperative high-resolution magnetic resonance (MR) sequence and investigate the correlations between the neuroimaging parameters and the prognosis of microvascular decompression (MVD). METHODS: 106 patients with HFS and 121 age-matched and gender-matched healthy controls (HCs) were included in this study. Electronic medical records and neuroimaging data were collected. The facial-nerve angle, cross-sectional area of CPA cistern and length of the cistern segment of the facial nerve were measured on affected side and unaffected as well as healthy individuals. The receiver operating characteristic curve was used for assessing the predictive performances. RESULTS: 100 patients achieved complete relief postoperatively. 13 of the 100 complete relief patients developed a relapse in the follow-up. The preoperative facial-pontine angle and cross-sectional area of the CPA cistern on the affected side was significantly smaller than the unaffected side and HC. The facial-pontine angle and the cross-sectional area of the CPA cistern was significantly smaller in recurrent group than the non-recurrent group. The AUC value of both facial-pontine angle and cross-sectional area of the CPA cistern were over 0.7. CONCLUSION: Small facial-nerve angle and cross-sectional area of CPA cistern may be regarded as the possible pathogenesis of primary HFS. The measurement of facial-nerve angle and cross-sectional area of CPA cistern preoperatively might be used to predict the surgical effect of MVD.

Long Noncoding RNA LINC-PINT Suppresses Cell Proliferation, Invasion, and EMT by Blocking Wnt/ß-Catenin Signaling in Glioblastoma.

Background: Glioblastoma (GBM) represents the most aggressive glioma with high invasive potential. Recent studies proved the involvement of epithelial-mesenchymal transition (EMT) process in increasing the malignancy and invasiveness of GBM. LncRNAs have been verified to play pivotal roles in human disease including GBM. However, the molecular mechanisms of lncRNA-mediated EMT in GBM remain largely unknown. LINC-PINT, a LncRNA which has never been studied in GBM before, was predicted to be negatively associated with EMT in GBM. This study aimed to explore the biological function and the EMT relevance of LINC-PINT in GBM and further explore the molecular mechanism. Methods: The bioinformatic prediction data of LINC-PINT in GBM was derived from The Cancer Genome Atlas (TCGA) database by R software and GEPIA website. qRT-PCR assay was performed to detect the expression level of LINC-PINT in GBM cell lines. Cell counting kit-8 (CCK8), clone formation, transwell, and wound healing assays were performed to determine the biological function of LINC-PINT in vivo. Tumor xenograft experiment and tumor peritoneal metastasis experiments were performed to verify the in vivo function. Western blot and immunofluorescence staining assays were carried out to detect the relevance of LINC-PINT with EMT and Wnt/ß-catenin signaling. Rescue assays were performed to check the regulation mechanism of LINC-PINT/Wnt signaling/EMT axis in GBM. Results: LINC-PINT was downregulated in GBM cell lines. LINC-PINT suppressed cell progression, invasion, and EMT in GBM. LINC-PINT blocked Wnt/ß-catenin signaling in GBM. Conclusion: LINC-PINT suppressed cell proliferation, invasion, and EMT by blocking Wnt/ß-catenin signaling in GBM.

Exogenous Netrin-1 Inhibits Autophagy of Ischemic Brain Tissues and Hypoxic Neurons via PI3K/mTOR Pathway in Ischemic Stroke.

BACKGROUND AND OBJECTIVE: Ischemic stroke is a serious disease that endangers human health. How to reduce the damage of neurons in ischemic regions is an urgent problem to be explored. Autophagy is an important pathophysiological process in cerebral ischemia and Netrin-1 is an effective neuroprotective protein. This study aims to investigate the effect of Netrin-1 on autophagy of ischemic brain tissues and hypoxic neurons. METHODS: We constructed rat persistent middle cerebral artery occlusion model in vivo and constructed the Oxygen Glucose-Deprivation model in vitro. Rats and cells were treated with or without Netrin-1. Western blot analysis was performed to detect autophagy related proteins LC3B, P62 and pathway related proteins PI3K, p-PI3K, mTOR, p-mTOR. CCK-8 assay was performed to detect the viability of hypoxic neurons. We also performed western-blot analysis and qRT-PCR test to detect levels of Netrin-1 protein and mRNA. RESULTS: Autophagy enhanced both in ischemic brain tissues and hypoxic neurons. Netrin-1 inhibited autophagy through PI3K/mTOR pathway both in vivo and in vitro. At the same time, we found that exogenous Netrin-1 can promote the secretion of Netrin-1 protein by neurons themselves, which indicated that Netrin-1 can further amplify the neuroprotective effect through the positive feedback mechanism. CONCLUSIONS: Exogenous Netrin-1 alleviates damage of ischemic brain tissues and enhances viability of hypoxic neurons by inhibiting autophagy via PI3K/mTOR pathway. This effect can be amplified by positive feedback mechanism.

CXCL12 has therapeutic value in facial nerve injury and promotes Schwann cells autophagy and migration via PI3K-AKT-mTOR signal pathway.

Facial nerve injury is a clinically common disease accompanied by demyelination of damaged nerves. The remyelination of damaged nerves and the unsatisfactory function recovery are problems that have been plaguing people for a long time. The role that CXCL12 plays after facial nerve injury remains unknown. Our experiments found that the expression of CXCL12 was up-regulated in the early stage of facial nerve injury and decreased after two weeks. Further research found that CXCL12 had no effect on Schwann cells proliferation, apoptosis and cell cycle, while significantly promoted Schwann cells migration. Treatment with CXCL12 decreased the phosphorylation of PI3K, AKT and mTOR, but increased autophagy marker LC3II/I. The CXCL12-induced Schwann cells migration was significantly attenuated by inhibition of autophagy and activation of PI3K pathway through pretreatment with 3-MA and IGF-1 respectively, and this effect was enhanced by PI3K pathway inhibitor LY294002. Animal experiment also confirmed that CXCL12 could improve facial nerve function and myelin regeneration. The findings of this study indicate that CXCL12 can promote the migration of Schwann cells and potentially become a key molecule in the repair of facial nerve injury.