Toll-like receptor 4 deficiency in Purkinje neurons drives cerebellar ataxia by impairing the BK channel-mediated after-hyperpolarization and cytosolic calcium homeostasis.

Toll-like receptor (TLR) 4 contributes to be the induction of neuroinflammation by recognizing pathology-associated ligands and activating microglia. In addition, numerous physiological signaling factors act as agonists or antagonists of TLR4 expressed by non-immune cells. Recently, TLR4 was found to be highly expressed in cerebellar Purkinje neurons (PNs) and involved in the maintenance of motor coordination through non-immune pathways, but the precise mechanisms remain unclear. Here we report that mice with PN specific TLR4 deletion (TLR4PKO mice) exhibited motor impairments consistent with cerebellar ataxia, reduced PN dendritic arborization and spine density, fewer parallel fiber (PF) - PN and climbing fiber (CF) - PN synapses, reduced BK channel expression, and impaired BK-mediated after-hyperpolarization, collectively leading to abnormal PN firing. Moreover, the impaired PN firing in TLR4PKO mice could be rescued with BK channel opener. The PNs of TLR4PKO mice also exhibited abnormal mitochondrial structure, disrupted mitochondrial endoplasmic reticulum tethering, and reduced cytosolic calcium, changes that may underly abnormal PN firing and ultimately drive ataxia. These results identify a previously unknown role for TLR4 in regulating PN firing and maintaining cerebellar function.

Deferoxamine Mitigates Ferroptosis and Inflammation in Hippocampal Neurons After Subarachnoid Hemorrhage by Activating the Nrf2/TXNRD1 Axis.

Ferroptosis is a distinct peroxidation-driven form of cell death tightly involved in subarachnoid hemorrhage (SAH). This study delved into the mechanism of deferoxamine (DFO, an iron chelator) in SAH-induced ferroptosis and inflammation. SAH mouse models were established by endovascular perforation method and injected intraperitoneally with DFO, or intraventricularly injected with the Nrf2 pathway inhibitor ML385 before SAH, followed by detection of neurological function, blood-brain barrier (BBB) permeability, and brain water content. Apoptotic level of hippocampal neurons, symbolic changes of ferroptosis, and levels of pro-inflammatory cytokines were assessed using TUNEL staining, Western blotting, colorimetry, and ELISA. The localization and expression of nuclear factor-erythroid 2-related factor 2 (Nrf2) were detected. HT22 cells were exposed to Hemin as in vitro SAH models and treated with FIN56 to induce ferroptosis, followed by evaluation of the effects of DFO on FIN56-treated HT22 cells. The regulation of Nrf2 in thioredoxin reductase 1 (TXNRD1) was analyzed by co-immunoprecipitation and Western blotting. Moreover, HT22 cells were treated with DFO and ML385 to identify the role of DFO in the Nrf2/TXNRD1 axis. DFO extenuated brain injury, and ferroptosis and inflammation in hippocampal neurons of SAH mice. Nrf2 localized at the CA1 region of hippocampal neurons, and DFO stimulated nuclear translocation of Nrf2 protein in hippocampal neurons of SAH mice. Additionally, DFO inhibited ferroptosis and inflammatory responses in FIN56-induced HT22 cells. Nrf2 positively regulated TXNRD1 protein expression. Indeed, DFO alleviated FIN56-induced ferroptosis and inflammation via activation of the Nrf2/TXNRD1 axis. DFO alleviated neurological deficits, BBB disruption, brain edema, and brain injury in mice after SAH by inhibiting hippocampal neuron ferroptosis via the Nrf2/TXNRD1 axis. DFO ameliorates SAH-induced ferroptosis and inflammatory responses in hippocampal neurons by activating the Nrf2/TXNRD1 axis.

An inflammatory gene-related prognostic risk score model for prognosis and immune infiltration in glioblastoma.

This study aimed to screen for key genes related to the prognosis of patients with glioblastoma (GBM). First, bioinformatics analysis was performed based on databases such as TCGA and MSigDB. Inflammatory-related genes were obtained from the MSigDB database. The TCGA-tumor samples were divided into cluster A and B groups based on consensus clustering. Multivariate Cox regression was applied to construct the risk score model of inflammatory-related genes based on the TCGA database. Second, to understand the effects of model characteristic genes on GBM cells, U-87 MG cells were used for knockdown experiments, which are important means for studying gene function. PLAUR is an unfavorable prognostic biomarker for patients with glioma. Therefore, the model characteristic gene PLAUR was selected for knockdown experiments. The prognosis of cluster A was significantly better than that of cluster B. The verification results also demonstrate that the risk score could predict overall survival. Although the immune cells in cluster B and high-risk groups increased, no matching survival advantage was observed. It may be that stromal activation inhibits the antitumor effect of immune cells. PLAUR knockdown inhibits tumor cell proliferation, migration, and invasion, and promoted tumor cell apoptosis. In conclusion, a prognostic prediction model for GBM composed of inflammatory-related genes was successfully constructed. Increased immune cell expression may be linked to a poor prognosis for GBM, as stromal activation decreased the antitumor activity of immune cells in cluster B and high-risk groups. PLAUR may play an important role in tumor cell proliferation, migration, invasion, and apoptosis.

Uncover DNA damage and repair-related gene signature and risk score model for glioma.

BACKGROUND: Glioma is a common primary central nervous system tumor with complex pathogenesis. DNA damage and repair (DDR) is widely involved in regulating cell proliferation and tumorigenesis by correcting and repairing DNA damage mechanisms. Recent studies have reported the following properties in cancer cells in glioma, increased DNA damage and reduced DNA repair capacity. However, the relationship between glioma and DDR-related genes was unclear. METHODS: DDR-related risk score model was built. The validity of this model was validated in detail through the Kaplan-Meier survival analysis, tumor mutational burden (TMB) analysis, immune cell infiltration, sensitivity to treatment regimens. Moreover, the model's adaptability was validated in different glioma data cohorts and different glioma subgroups. To further investigate the molecular mechanism of one of DDR-related gene (NUDT1) in glioma, U251 cell was used for the knockdown experiment, followed by MTT, wound healing and transwell analysis. RESULTS: Ten prognostic-related DDR-related signature genes were obtained, including EID3, MGMT, YWHAG, PMS1, SHPRH, HUS1, NUDT1, GADD45G, APEX1 and FAM175A. The RT-qPCR results suggested that the latter five genes were highly expressed in glioma patients. Interestingly, high TMB score had longer survival. In high-risk score groups, reduced immune cell infiltration in the tumor microenvironment lead to poorer patient outcomes. Sensitivity to treatment regimens analysis indicated that low-risk score groups were more sensitive to chemotherapeutics. Moreover, the risk score model had a good prediction effect on different glioma datasets and different glioma subgroups. In vitro mechanism study showed that knockdown of NUDT1 reduced tumorigenesis. Furthermore, knockdown of NUDT1 remarkably reduced the expression level of HIF-1α. CONCLUSION: DDR-related risk score model built-in this work has good predictive performance for glioma.Key messagesTen prognostic-related DDR-related signature genes were obtained, including EID3, MGMT, YWHAG, PMS1, SHPRH, HUS1, NUDT1, GADD45G, APEX1 and FAM175A.In high-risk score groups, reduced immune cell infiltration in the tumor microenvironment leads to poorer patient outcomes.The risk score model had a good prediction effect on different glioma datasets and different glioma subgroups.Knockdown of NUDT1 reduced tumorigenesis of glioma and remarkably reduced the expression level of HIF-1α.

miR-1297 sensitizes glioma cells to temozolomide (TMZ) treatment through targeting adrenomedullin (ADM).

BACKGROUND: Gliomas account for about 80% of all malignant brain and other central nervous system (CNS) tumors. Temozolomide (TMZ) resistance represents a major treatment hurdle. Adrenomedullin (ADM) has been reported to induce glioblastoma cell growth. METHODS: Cell viability was measured using the CCK-8 assay. The apoptosis analysis was performed using the Annexin V-FITC Apoptosis Detection Kit. The mitochondrial membrane potential was determined by JC-1 staining. A nude mouse tumor assay was used to detect tumor formation. Hematoxylin and eosin (H&E) and immunohistochemical (IHC) staining were performed in tissue sections. Activation of Akt and Erk and expression of apoptosis-related proteins were determined by immunoblotting. RESULTS: ADM expression has been found upregulated in TMZ -resistant glioma samples based on bioinformatics and experimental analyses. Knocking down ADM in glioma cells enhanced the suppressive effects of TMZ on glioma cell viability, promotive effects on cell apoptosis, and inhibitory effects on mitochondrial membrane potential. Moreover, ADM knockdown also enhanced TMZ effects on Bax/Bcl-2, Akt phosphorylation, and Erk1/2 phosphorylation. Bioinformatics and experimental investigation indicated that miR-1297 directly targeted ADM and inhibited ADM expression. miR-1297 overexpression exerted similar effects to ADM knockdown on TMZ-treated glioma cells. More importantly, under TMZ treatment, inhibition of miR-1297 attenuated TMZ treatment on glioma cells; ADM knockdown partially attenuated the effects of miR-1297 inhibition on TMZ-treated glioma cells. CONCLUSIONS: miR-1297 sensitizes glioma cells to TMZ treatment through targeting ADM. The Bax/Bcl-2, Akt, and Erk1/2 signaling pathways, as well as mitochondrial functions might be involved.

Extracellular vesicles derived from bone marrow mesenchymal stem cells alleviate neurological deficit and endothelial cell dysfunction after subarachnoid hemorrhage via the KLF3-AS1/miR-83-5p/TCF7L2 axis.

BACKGROUND: New data are accumulating on the effects of mesenchymal stem cell-derived extracellular vesicles (MSC-EVs) in cerebrovascular diseases. We explored the potential role of KLF3-AS1-containing bone marrow MSC-EVs (BMSC-EVs) in a rat model of subarachnoid hemorrhage (SAH). METHODS: A rat model of SAH was established by endovascular perforation method, into which KLF3-AS1-containing EVs from BMSCs or miR-183-5p mimic were injected. Further, brain microvascular endothelial cells (BMECs) were induced by oxyhemoglobin (OxyHb) to simulate in vitro setting, which were co-cultured with KLF3-AS1-containing EVs from BMSCs. Effects of KLF3-AS1 on neurological deficits in vivo and endothelial cell dysfunction in vitro were investigated. We also performed bioinformatics analysis to predict downstream factors miR-183-5p and TCF7L2, which were verified by RIP, RNA pull-down and luciferase activity assays. RESULTS: BMSC-EVs was demonstrated to alleviate neurological deficits in SAH rats and endothelial cell dysfunction in OxyHb-induced BMECs. In addition, BMSC-EVs were shown to deliver KLF3-AS1 to BMECs, where KLF3-AS1 bound to miR-183-5p and miR-183-5p targeted TCF7L2. In vivo results confirmed that BMSC-EVs regulated the KLF3-AS1/miR-183-5p/TCF7L2 signaling axis to attenuate neurological deficit and endothelial dysfunction after SAH. CONCLUSION: Overall, KLF3-AS1 delivered by BMSC-EVs upregulate TCF7L2 expression by binding to miR-138-5p, thus attenuating neurological deficits and endothelial dysfunction after SAH.

LncRNA UCA1/miR-182-5p/MGMT axis modulates glioma cell sensitivity to temozolomide through MGMT-related DNA damage pathways.

Glioblastoma (GBM) is the most malignant subtype of gliomas. GBM resistance to temozolomide (TMZ) remains a huge challenge. O6-methylguanine-DNA methyltransferase (MGMT) is mainly responsible for repairing DNA alkylation damage caused by alkylating drugs such as TMZ; therefore, it has been regarded as the major cause of the resistance to TMZ. Hematoxylin and eosin (H&E) and immunohistochemical (IHC) staining were performed in tissue sections. LncRNA urothelial cancer-associated 1 (UCA1) knockdown was conducted via the transfection of the plasmid containing small interfering RNA (siRNA) targeting lncRNA UCA1. Cell viability and apoptosis were examined using MTT assay and flow cytometry. Nude mouse tumorigenicity assay was performed to detect tumor formation in vivo. MGMT expression and lncRNA UCA1 expression were increased in high-grade glioma tissues and cells. UCA1 knockdown in glioma cells enhanced TMZ efficacies in affecting glioma cell viability, cell apoptosis, MGMT protein level, and DNA damage markers in vitro, as well as tumorigenesis in vivo. Moreover, miR-182-5p targeted UCA1 and MGMT; miR-182-5p inhibited MGMT expression. Similar to UCA1 knockdown, miR-182-5p overexpression also promoted TMZ effects on glioma cell phenotype, MGMT expression level, and the levels of DNA damage markers. Under TMZ treatment, the efficacies of UCA1 knockdown in MGMT expression level and glioma cell sensitivity to TMZ were notably reversed after miR-182-5p overexpression. Taken together, we demonstrate the lncRNA UCA1/miR-182-5p/MGMT axis modulates glioma cell sensitivity to TMZ via MGMT-related DNA damage pathways.

Mesenchymal stem cell-derived extracellular vesicles prevent glioma by blocking M2 polarization of macrophages through a miR-744-5p/TGFB1-dependent mechanism.

AIM: Our current study is conducted with intention to explore the regulatory mechanism of mesenchymal stem cell (MSC)-derived extracellular vesicle (EV)-miR-744-5p in glioma. METHODS: Expression patterns of TGFB1, TGFBR1, and miR-744-5p were determined. EVs were isolated from human MSCs, which were characterized. Then, macrophages were co-cultured with MSCs with ectopic miR-744-5p expression to explore its role in cell proliferation, invasion, and migration capabilities. A nude mouse model of glioma xenograft was developed to observe the tumorigenesis and metastasis ability of glioma in vivo. RESULTS: TGFB1 and TGFBR1 were upregulated in glioma. TGFB1 promoted M2 polarization of macrophages through theMAPK signaling, thereby promoting the progression of glioma. MSC-EVs suppressed TGFB1 expression in macrophages and inhibited M2 polarization of macrophages. MSC-EVs-miR-744-5p/TGFB1/MAPK axis inhibited M2 polarization of macrophages and reduced the malignant phenotypes of glioma cells. In vivo experiments verified that MSC-EVs-miR-744-5p inhibited the polarization of macrophage M2 and prevented glioma progression. CONCLUSION: Taken together, MSC-EVs-miR-744-5p may suppress the MAPK signaling activity by downregulating TGFB1, and then inhibit polarization of macrophages M2, thereby preventing the progression of glioma. Graphical Headlights 1. TGFB1 promotes the M2 polarization of macrophages via the MAPK signaling. 2. miR-744-5p carried by MSC-EVs targets and inhibits TGFB1. 3. MSC-EV-miR-744-5p inhibits M2 polarization of macrophages to prevent glioma progression. 4. miR-744-5p loaded by MSC-EVs may be a preventive strategy against glioma.

Shape related features of intracranial aneurysm are associated with rupture status in a large Chinese cohort.

BACKGROUND: To investigate the prevalence of small ruptured saccular intracranial aneurysms (sIA) in a Chinese cohort and to identify factors associated with rupture status of sIAs. METHODS: Consecutive patients with confirmed sIAs by DSA from January 2015 to July 2019 were included. Demographic and aneurysmal features, including maximal diameter, location, irregularity (lobulated or with blebs), and aspect ratio (AR, defined as height divided by neck width) were recorded and analyzed. Mixed effect logistic regression was used in multivariate analysis. RESULTS: We analyzed 1514 sIAs in a Chinese cohort of 1216 patients, including 651 ruptured and 863 unruptured sIAs. Median aneurysm size was 5.7 mm for ruptured aneurysms, with 66.1% <7 mm in maximal diameter, and 40.2% measuring <5 mm. The median PHASES score of ruptured sIAs was 5. In multivariate analysis, male sex, hypertension, locations other than the internal carotid artery, irregularity (lobulated or with blebs), and higher AR were independently associated with rupture status (OR for irregularity, 2.88, 95% CI 2.20 to 3.77, p<0.001; OR for AR, 1.12, 95% CI 1.01 to 1.24, p=0.036). However, maximal diameter was not significantly associated with rupture status (p=0.72). CONCLUSIONS: In this cohort, ruptured sIAs were frequently smaller than 7 mm. Shape related features, such as irregularity and higher AR, were associated with the ruptured status of sIAs, irrespective of diameter. PHASES seems to be inadequate in sIA risk stratification. Shape related parameters may be further investigated in prospective studies.

Transcription Factor ELF1 Activates MEIS1 Transcription and Then Regulates the GFI1/FBW7 Axis to Promote the Development of Glioma.

Glioma is the most common malignancy in the central nervous system with no immediate prospect of a cure. Comprehensive understanding on the pathogenesis of the disorder contributes to a better outcome. Herein, we aimed to investigate whether transcription factors erythroblast transformation-specific (ETS) transcription factor (ELF1), myeloid ecotropic viral integration site 1 (MEIS1), and growth factor independence 1 (GFI1)/F-box/WD repeat-containing protein 7 (FBW7) mediate progression of glioma. ELF1, MEIS1, and GFI1 were upregulated in glioma cells and tissues, as ELF1 was correlated with poor prognosis. Bioinformatics analysis identified the binding between ELF1 and MEIS1 as well as between GFI1 and FBW7, confirmed by chromatin immunoprecipitation (ChIP) experiments. Functional experiment indicated that silencing of ELT1 decreased MEIS1 expression and that overexpression of MEIS1 increased GFI1 expression by activating GFI1 enhancer but decreased FBW7 expression. Importantly, silencing of ELF1 decreased the capacities of proliferation, migration, and invasion of glioma cells whereas it increased apoptosis, supported by increased capase-3 and decreased matrix metalloproteinase-9 (MMP-9) and proliferating cell nuclear antigen (PCNA) expression. Moreover, an in vivo experiment confirmed the inhibitory role of silenced ELF1 in tumor growth, with a decreased level of MEIS1 and GFI1. Taken together, our study elucidated a potential mechanism that ELF1 promoted cell progression by increasing GFI1 and METS1 as well as decreasing FBW7 expression in glioma.

Endovascular Intervention with a Low-profile Visualized Intraluminal Support Stent Versus Surgical Clipping for Blood Blister-like Aneurysms : A Retrospective Study.

PURPOSE: Blood blister-like aneurysms (BBAs) have a high risk of early recurrence and postoperative rebleeding. This study compared the clinical outcomes and complications between endovascular intervention with low-profile visualized intraluminal support (LVIS) stent-assisted coiling and the surgical clipping in patients with BBAs. METHODS: This retrospective study enrolled 39 patients with BBAs who underwent endovascular intervention with LVIS stent-assisted coiling (n = 21) or surgical clipping (n = 18) between January 2013 and July 2018. Primary outcomes were mortality and modified Rankin scale (mRS). Secondary outcomes were hospital stay, intensive care unit (ICU) stay and operation parameters. Complications were also retrospectively collated. RESULTS: At baseline, the two groups were well balanced in patient characteristics. The hospital stays, ICU stays, operation time and intraoperative infusion volume were all significantly lower in LVIS group than that in clipping group (p < 0.05). A second operation was performed in 6 cases in the clipping group but none in the LVIS group (p = 0.006). The mean mRS score in the LVIS group was significantly lower than that of the clipping group both at hospital discharge and final follow-up (p < 0.001). Adverse outcomes occurred in 1 case in LVIS group and 7 in clipping group, with significant difference (p = 0.015). Complications were reported in 8 cases in LVIS group and 16 cases in clipping group, with significant difference (p < 0.001). CONCLUSION: The endovascular intervention with LVIS stent-assisted coiling has better prognosis than surgical clipping. It decreased the risk of a second operation and procedure-related complications compared with surgical clipping.

LncRNA DGCR5 plays a tumor-suppressive role in glioma via the miR-21/Smad7 and miR-23a/PTEN axes.

Glioma is one of the most commonly diagnosed brain malignancies with a high cancer-related death rate in humans. The prognosis of glioma patients is still unsatisfactory. In the present study, we attempted to identify lncRNAs and miRNAs that might be related to NF-κB-mediated epithelial-mesenchymal transition in glioma cells based on online microarray expression profiles, and investigate the specific effects of lncRNA-miRNA-mRNA axes on glioma cell phenotypes. Herein, we identified lncRNA DGCR5 as a downregulated lncRNA in glioma that was negatively regulated by NF-κB1 in an NF-κB1 RE-dependent manner. LncRNA DGCR5 overexpression significantly inhibited the capacity of glioma cells to proliferate, migrate, and invade, whereas promoted the apoptosis of glioma cells. Moreover, lncRNA DGCR5 overexpression upregulated the epithelial marker E-cadherin while downregulating the mesenchymal marker VIM, as well as Snai2 and TWIST. Regarding the underlying molecular mechanisms, lncRNA DGCR5 could inhibit miR-21 and miR-23a expression, and miR-21 or miR-23a overexpression significantly reversed the tumor-suppressive effects of lncRNA DGCR5 overexpression. LncRNA DGCR5 exerted its tumor-suppressive effects through the DGCR5/miR-21/Smad7 and DGCR5/miR-23a/PTEN axes. In conclusion, lncRNA DGCR5 suppresses the capacity of glioma cells to migrate and invade via miR-21/Smad7, whereas it inhibits the proliferation and enhances the apoptosis of glioma cells through miR-23a/PTEN.

MUC15 promotes growth and invasion of glioma cells by activating Raf/MEK/ERK pathway.

MUC15 is a novel mucin associated with the cell membrane that is overexpressed in human gliomas. Its function in glioma is unclear. In this study, high MUC15 levels were detected in glioma tissues and cells. We found that transfection with MUC15 siRNA in U251 and T98G cells reduced MUC15 expression and decreased cell proliferation, invasion, and migration (P < .05). After transfecting U251 and T98G cells with pcDNA3.1-myc-His-MUC15 plasmid to overexpress MUC15, MUC15 expression was significantly upregulated and cell proliferation, invasion, and migration were increased (P < .05). MUC15 activated the Raf/MEK/ERK signalling pathway and the ERK inhibitor PD98059 partly reversed MUC15-enhanced proliferation, invasion, and migration of glioma cells (P < .05). The results indicate that MUC15 plays a part in glioma tumorigenesis, and the Raf/MEK/ERK signalling is involved in the regulation of MUC15 on glioma cell activity.

[Experimental study on animal with automatic drug injection based on predictive control for vascular interventional therapy].

This paper focuses on the animal experiment of automatic drug delivery based on predictive control for vascular interventional therapy. Improvement of drug delivery system based on predictive control used in simulated experiments was put forward after the presence of time varying parameters and the characteristics of individual differences of animal had been studied. The adaptability of time varying parameters and fault tolerance of the system were also enhanced. Different injection methods were tested on animals. It is proved that higher target blood concentration can be reached while injecting during diastolic than that while injecting during systolic or injecting at a constant speed within the whole cardiac cycle. The results also showed that the improved drug injection system based on predictive control which synchronizes with the cardiac cycle could be applied to clinical trials.

Two anatomic variations of the vertebral artery in four patients.

In this article, we present four cases of rare anomalous aortic arch and vertebral arteries and discuss the possible embryologic etiologies. These include two cases in which the right vertebral artery originated from the right common carotid artery associated with an aberrant right subclavian artery originating from the middle of the aortic arch and two cases in which the left vertebral artery had a double origin from the left subclavian artery and aortic arch.