Mesenchymal Stem Cell-Derived Extracellular Vesicles Alleviate Brain Damage Following Subarachnoid Hemorrhage via the Interaction of miR-140-5p and HDAC7.

Subarachnoid hemorrhage (SAH) triggers severe neuroinflammation and cognitive impairment, where microglial M1 polarization exacerbates the injury and M2 polarization mitigates damage. Mesenchymal stem cell-derived extracellular vesicles (MSC-EVs), carrying microRNA (miR)-140-5p, offer therapeutic promise by targeting the cAMP/PKA/CREB pathway and modulating microglial responses, demonstrating a novel approach for addressing SAH-induced brain injury. This research explored the role of miR-140-5p delivered by MSC-EVs in mitigating brain damage following SAH. Serum from SAH patients and healthy individuals was analyzed for miR-140-5p and cAMP levels. The association between miR-140-5p levels, brain injury severity, and patient survival was examined, along with the target relationship between miR-140-5p and histone deacetylases 7 (HDAC7). MSC-EVs were characterized for their ability to cross the blood-brain barrier and modulate the HDAC7/AKAP12/cAMP/PKA/CREB axis, reducing M1 polarization and inflammation. The therapeutic effect of MSC-EV-miR-140-5p was demonstrated in an SAH mouse model, showing reduced neuronal apoptosis and improved neurological function. This study highlights the potential of MSC-EV-miR-140-5p in mitigating SAH-induced neuroinflammation and brain injury, providing a foundation for developing MSC-EV-based treatments for SAH.

Nrf2 activation by neferine mitigates microglial neuroinflammation after subarachnoid hemorrhage through inhibiting TAK1-NF-κB signaling.

Oxidative stress and neuroinflammation are two major causes leading to early brain injury after subarachnoid hemorrhage (SAH). Nuclear factor E2-related factor 2 (Nrf2) is a critical transcription factor that contributes to antioxidant responses. Additionally, Nrf2 could inhibit transforming growth factor beta-activated kinase 1 (TAK1), which plays a vital role in microglial activation-mediated neuroinflammation. Neferine (NE) exhibits considerable protective effects in diverse disease models. However, the detailed effect and mechanism of NE on SAH remain unknown. Our data showed that NE treatment significantly reduced behavior and cognitive impairment, and brain edema in the early period after SAH. In addition, NE mitigated SAH-induced oxidative damage, neuroinflammation, and neural death. Moreover, NE inhibited M1 microglial polarization and enhanced M2 phenotype microglia both in vivo and in vitro. Further investigations revealed that NE enhanced the Nrf2-antioxidant response element (ARE) signaling pathway and suppressed TAK1-NF-κB signaling. In contrast, depletion of Nrf2 by ML385 suppressed Nrf2-ARE signaling, induced TAK1-NF-κB activation, and further promoted M1 microglial polarization. Additionally, ML385 abated the neuroprotective effects of NE against SAH. Notably, LPS also aggravated TAK1-NF-κB activation and reversed the beneficial effects of NE after SAH. In summary, NE provides protection after SAH by inhibiting oxidative stress and modulating microglial polarization through Nrf2 activation and TAK1-NF-κB suppression.

Nrf-2 modulates excitability of hippocampal neurons by regulating ferroptosis and neuroinflammation after subarachnoid hemorrhage in rats.

Excitability of hippocampal neurons in subarachnoid hemorrhage (SAH) rats has not been well studied. The rat SAH model was applied in this study to explore the role of nuclear factor E2-related factor (Nrf-2) in the early brain injury of SAH. The neural excitability of CA1 pyramidal cells (PCs) in SAH rats was evaluated by using electrophysiology experiments. Ferroptosis and neuroinflammation were measured by ELISA, transmission electron microscopy and western blotting. Our results indicated that SAH induced neurological deficits, brain edema, ferroptosis, neuroinflammation and neural excitability in rats. Ferrostatin-1 treatment significantly decreased the expression and distribution of IL-1ß, IL-6, IL-10, TGF-ß and TNF-α. Inhibiting ferroptosis by ferrostatin-1 can attenuate neural excitability, neurological deficits, brain edema and neuroinflammation in SAH rats. Inhibiting the expression of Nrf-2 significantly increased the neural excitability and the levels of IL-1ß, IL-6, IL-10, TGF-ß and TNF-α in Fer-1-treated SAH rats. Taken together, inhibiting the Nrf-2 induces early brain injury, brain edema and the inflammatory response with increasing of neural excitability in Fer-1-treated SAH rats. These results have indicated that inhibiting ferroptosis, neuroinflammation and neural excitability attenuates early brain injury after SAH by regulating the Nrf-2.

Gamma frequency entrainment rescues cognitive impairment by decreasing postsynaptic transmission after traumatic brain injury.

INTRODUCTION: The relationship between oscillatory activity in hippocampus and cognitive impairment in traumatic brain injury (TBI) remains unclear. Although TBI decreases gamma oscillations and 40 Hz light flicker improves TBI prognosis, the effects and mechanism of rhythmic flicker on TBI remain unclear. AIMS: In this study, we aimed to explore whether light flicker could reverse cognitive deficits, and further explore its potential mechanisms in TBI mouse model. METHODS: The Morris water maze test (MWM), step-down test (SDT), and novel object recognition test (NOR) were applied to evaluate the cognitive ability. The local field potential (LFP) recording was applied to measure low gamma reduction of CA1 in hippocampus after TBI. And electrophysiological experiments were applied to explore effects of the gamma frequency entrainment on long-term potentiation (LTP), postsynaptic transmission, and intrinsic excitability of CA1 pyramidal cells (PCs) in TBI mice. Immunofluorescence staining and western blotting were applied to explore the effects of 40 Hz light flicker on the expression of PSD95 in hippocampus of TBI mice. RESULTS: We found that 40 Hz light flicker restored low gamma reduction of CA1 in hippocampus after TBI. And 40 Hz, but not random or 80 Hz light flicker, reversed cognitive impairment after TBI in behavioral tests. Moreover, 40 Hz light flicker improved N-methyl-D-aspartate (NMDA) receptor-dependent LTP (LTPNMDAR ) and L-type voltage-gated calcium channel-dependent LTP (LTPL-VGCC ) after TBI treatment. And gamma frequency entrainment decreased excitatory postsynaptic currents (EPSCs) of CA1 PCs in TBI mice. Our results have illustrated that 40 Hz light flicker could decrease intrinsic excitability of PCs after TBI treatment in mice. Furthermore, 40 Hz light flicker decreased the expression of PSD95 in hippocampus of TBI mice. CONCLUSION: These results demonstrated that 40 Hz light flicker rescues cognitive impairment by decreasing postsynaptic transmission in PCs after TBI treatment in mice.

The proteins derived from platelet-rich plasma improve the endothelialization and vascularization of small diameter vascular grafts.

Vascular transplantation has become an ideal substitute for heart and peripheral vascular bypass therapy and tissue-engineered vascular grafts (TEVGs) present an attractive potential solution for vascular surgery. However, small diameter (Ф < 6 mm) vascular do not have ideal TEVGs for clinical use. Platelet-rich plasma (PRP), a key source of bioactive molecules, has been confirmed to promote tissue repair and regeneration. In this study, we prepared PRP-loaded TEVGs (PRP-TEVGs) by electrospinning, investigated the characterization of TEVGs, and verified the effect of PRP-TEVGs in vivo and in vitro experiments. The results suggested that PRP-TEVGs had good biocompatibility, released growth factors stably, promoted cell proliferation and migration significantly, up-regulated the expression of endothelial NO synthase (eNOS) in functional vascular endothelial cells (VECs), and maintained the stability of the endothelial structure. In vivo experiments suggest that PRP can promote rapid endothelialization and reconstruction of TEVGs. Overall, this finding indicated that PRP could promote the rapid vascular endothelialization of small-diameter TEVGs by improving contractile vascular smooth muscle cells (VSMCs) regeneration, and maintaining the integrity and functionality of VECs.

Dexmedetomidine Inhibits Gasdermin D-Induced Pyroptosis via the PI3K/AKT/GSK3ß Pathway to Attenuate Neuroinflammation in Early Brain Injury After Subarachnoid Hemorrhage in Rats.

Subarachnoid hemorrhage (SAH) is one kind of life-threatening stroke, which leads to severe brain damage. Pyroptosis plays a critical role in early brain injury (EBI) after SAH. Previous reports suggest that SAH-induced brain edema, cell apoptosis, and neuronal injury could be suppressed by dexmedetomidine (Dex). In this study, we used a rat model of SAH to investigate the effect of Dex on pyroptosis in EBI after SAH and to determine the mechanisms involved. Pyroptosis was found in microglia in EBI after SAH. Dex significantly alleviated microglia pyroptosis via reducing pyroptosis executioner GSDMD and inhibited the release of proinflammatory cytokines induced by SAH. Furthermore, the reduction of GSDMD by Dex was abolished by the PI3K inhibitor LY294002. In conclusion, our data demonstrated that Dex reduces microglia pyroptosis in EBI after SAH via the activation of the PI3K/AKT/GSK3ß pathway.

[Retracted] MicroRNA­186 targets IGF­1R and exerts tumor-suppressing functions in glioma.

Following the publication of this paper, it was drawn to the Editors' attention by a concerned reader that certain of the cell migration assay data shown in Fig. 2C were strikingly similar to data that had appeared in different form in another article by different authors. Owing to the fact that the contentious data in the above article had already been published elsewhere prior to its submission to Molecular Medicine Reports, the Editor has decided that this paper should be retracted from the Journal. After having been in contact with the authors, they agreed with the decision to retract the paper. The Editor apologizes to the readership for any inconvenience caused. [Molecular Medicine Reports 16: 7821­7828, 2017; DOI: 10.3892/mmr.2017.7586].

Metformin Inhibits NLR Family Pyrin Domain Containing 3 (NLRP)-Relevant Neuroinflammation via an Adenosine-5'-Monophosphate-Activated Protein Kinase (AMPK)-Dependent Pathway to Alleviate Early Brain Injury After Subarachnoid Hemorrhage in Mice.

Neuroinflammation plays a key role in the pathogenesis of early brain injury (EBI) after subarachnoid hemorrhage (SAH). Previous studies have shown that metformin exerts anti-inflammatory effects and promotes functional recovery in various central nervous system diseases. We designed this study to investigate the effects of metformin on EBI after SAH. Our results indicate that the use of metformin alleviates the brain edema, behavioral disorders, cell apoptosis, and neuronal injury caused by SAH. The SAH-induced NLRP3-associated inflammatory response and the activation of microglia are also suppressed by metformin. However, we found that the blockade of AMPK with compound C weakened the neuroprotective effects of metformin on EBI. Collectively, our findings indicate that metformin exerts its neuroprotective effects by inhibiting neuroinflammation in an AMPK-dependent manner, by modulating the production of NLRP3-associated proinflammatory factors and the activation of microglia.

Transcriptome-Wide Analysis to Identify the Inflammatory Role of lncRNA Neat1 in Experimental Ischemic Stroke.

BACKGROUND: Ischemic stroke is one of the leading causes of mortality and disability worldwide. Following stroke, there is secondary neuroinflammation that promotes further injury. Identifying the long non-coding RNA (lncRNA) involved in neuroinflammation after cerebral ischemic stroke will promote the discovery of potential therapeutic targets. METHODS: We identified differentially expressed genes from genome-wide RNA-seq profiles of mice with focal ischemia using Gene Ontology Term Enrichment, Kyoto Encyclopedia of Genes and Genomes, and Gene Set Enrichment analyses. Immune cell infiltration deconvolution, protein-protein interaction network construction, and co-expression network analyses were also used to screen lncRNAs. In further experiments, lncRNA Neat1 knockdown animal models were developed by intraventricular injection of the antisense oligonucleotide before performing middle cerebral artery occlusion (MCAO). An enzyme-linked immunosorbent assay was performed to measure the level of cytokines. Hematoxylin-eosin staining and immunohistochemical staining were used to observe the changes in morphology. RESULTS: Enrichment analysis revealed that differential mRNAs induced neuroinflammation after MCAO. Immune deconvolution showed that the proportion of microglia gradually increased while monocytes decreased within 24 h. We identified six hub lncRNAs (Neat1, Gm10827, Trp53cor1, Mir670hg, C730002L08Rik, and Mir181a-hg) that were highly correlated with activated-microglia mRNAs (cor > 0.8). We found that Neat1 had the highest correlation coefficient with pro-inflammatory factor mRNA levels. In vivo experiments demonstrated that Neat1 had abnormally high expression after MCAO. Knockdown of Neat1 could significantly alleviate brain damage by reducing the number of activated microglia and reducing their release of proinflammatory cytokines. CONCLUSION: We identified inflammation-associated lncRNA Neat1 as crucial, which means it is a potential target for ischemic stroke treatment.

Resolvin D1 ameliorates Inflammation-Mediated Blood-Brain Barrier Disruption After Subarachnoid Hemorrhage in rats by Modulating A20 and NLRP3 Inflammasome.

Inflammation is typically related to dysfunction of the blood-brain barrier (BBB) that leads to early brain injury (EBI) after subarachnoid hemorrhage (SAH). Resolvin D1 (RVD1), a lipid mediator derived from docosahexaenoic acid, possesses anti-inflammatory and neuroprotective properties. This study investigated the effects and mechanisms of RVD1 in SAH. A Sprague-Dawley rat model of SAH was established through endovascular perforation. RVD1was injected through the femoral vein at 1 and 12 h after SAH induction. To further explore the potential neuroprotective mechanism, a formyl peptide receptor two antagonist (WRW4) was intracerebroventricularly administered 1 h after SAH induction. The expression of endogenous RVD1 was decreased whereas A20 and NLRP3 levels were increased after SAH. An exogenous RVD1 administration increased RVD1 concentration in brain tissue, and improved neurological function, neuroinflammation, BBB disruption, and brain edema. RVD1 treatment upregulated the expression of A20, occludin, claudin-5, and zona occludens-1, as well as downregulated nuclear factor-κBp65, NLRP3, matrix metallopeptidase 9, and intercellular cell adhesion molecule-1 expression. Furthermore, RVD1 inhibited microglial activation and neutrophil infiltration and promoted neutrophil apoptosis. However, the neuroprotective effects of RVD1 were abolished by WRW4. In summary, our findings reveal that RVD1 provides beneficial effects against inflammation-triggered BBB dysfunction after SAH by modulating A20 and NLRP3 inflammasome.

The treatment effects and the underlying mechanism of B cell translocation gene 1 on the oncogenesis of brain glioma.

OBJECTIVES: Glioma is characterized by cell over-proliferation, aggressive phenotype, and angiogenesis. B cell translocation gene 1 (BTG1) works as a tumor suppressor in various cancer types. We aimed to study the functions of BTG1 in glioma development. METHODS: We tested the BTG1 expressions in various glioma cell lines. T98G and U87 cells were transfected with siBTG1 and BTG1 expression vector, respectively, then assessing cell viability, cell migration, and invasion abilities. Flow cytometry was performed to analyze apoptosis and cell cycle distribution. The status of angiogenesis was assessed by In vitro angiogenesis assay. Quantitative polymerase chain reaction and Western blot analysis were used for expression analyses. The inhibitor FH535 (20 µM) and agonist LiCl (20 mM) of the Wnt/ß-catenin pathway were introduced to treat transfected cells. RESULTS: BTG1 was low-expressed in glioma cell lines. In T98G cell transfected with siBTG1, cell proliferation, migration, invasion, and angiogenesis abilities were notably increased, BTG1 silencing promoted the cell survival and cell cycle progression from G0/G1 to the S phase. In BTG overexpressed U87 cell, cell proliferation, migration, invasion, and angiogenesis abilities were significantly inhibited. In addition, cell apoptosis significantly increased and the number of G0/G1 phase cells was also significantly increased. We also found that the activation of Wnt/ß-catenin was significantly inhibited in BTG1 group. LiCl and FH535 treatments could partially reverse the effects of BTG1 on glioma cell viabilities. CONCLUSION: Our data suggested that BTG1 functions as a tumor suppressor in glioma, and the anticancer ability of BTG1 involves the repression of the Wnt/ß-catenin pathway.

Mir-758-5p Suppresses Glioblastoma Proliferation, Migration and Invasion by Targeting ZBTB20.

BACKGROUND/AIMS: To determine the cellular functions and clinical significance of micro-758-5p (miR-758-5p) in glioblastoma (GBM) by targeting zinc finger and BTB domain-containing protein 20 (ZBTB20). METHODS: Fifty-five paired GBM tissues and adjacent normal tissues, GBM cell lines (U118, LN-299, H4, A172, U87-MG, and U251), and normal human astrocyte cell line (HEB) were used. miR-758-5p mimics, ZBTB20 siRNA, and pcDNA3.1-ZBTB20 were transiently transduced into cancer cells independently or together. qRT-PCR was conducted to analyze the expression of miR-758-5p and ZBTB20. Luciferase reporter assays were performed to determine the effect of miR-758-5p on ZBTB20. Western blot was applied to measure the expression of ZBTB20, PCNA, and cleaved caspase3. Cell Counting Kit-8 (CCK8), colony formation, FACS, and Transwell assays were carried out to detect cellular proliferation, apoptosis, migration, and invasion. Xenograft experiments were implemented to evaluate tumor growth and metastasis in vivo. RESULTS: miR-758-5p was significantly downregulated in GBM tissues and cell lines compared with that in adjacent normal tissues and HEB cells. miR-758-5p overexpression inhibited the proliferation, migration, and invasion of GBM cells and induced apoptosis by regulating the ZBTB20 expression. Pearson correlation analysis also confirmed that miR-758-5p was inversely correlated with ZBTB20 in GBM tissues. miR-758-5p suppressed tumor growth and metastasis in vivo. The restored ZBTB20 expression partially rescued the miR-758-5p-induced inhibition of GBM cell proliferation, migration, and invasion. Kaplan-Meier curve analysis revealed that a high miR-758-5p expression indicated an enhanced prognosis of patients with GBM. CONCLUSION: miR-758-5p suppressed GBM progression by targeting ZBTB20. The miR-758-5p/ZBTB20 axis might be a promising therapeutic target for GBM treatment.

MicroRNA­186 targets IGF­1R and exerts tumor­suppressing functions in glioma.

Glioma is the most common malignant brain tumor in adults and represents one of the most aggressive and life­threatening types of cancer in humans. Increasing studies have revealed that microRNAs are abnormally expressed in various types of human cancer, and have oncogenic or tumor suppressive roles, which depend primarily on the type of cancer. The present study aimed to investigate the expression level and effects of microRNA­186 (miR­186) on glioma, and its underlying molecular mechanism. Reverse transcription­quantitative polymerase chain reaction (RT­qPCR) analysis was performed to detect the expression of miR­186 in glioma tissues and cell lines. Cell proliferation and invasion were assessed using MTT and cell invasion assays, respectively. Bioinformatics analysis and a luciferase reporter assay were performed to identify insulin­like growth factor 1 receptor (IGF­1R) as a novel target gene of miR­186. The mRNA expression level of IGF­1R was also measured using RT­qPCR analysis. The association between miR­186 and the expression of IGF­1R was evaluated using Spearman's correlation anal-ysis. Furthermore, the regulatory effects of miR­186 on the mRNA and protein expression of IGF­1R were determined using RT­qPCR and western blot analyses. Finally, the biological effects of the underexpression IGF­1R on glioma cells were investigated. The results showed that miR­186 was significantly downregulated in glioma tissues and cell lines. Inducing the expression of miR­186 suppressed glioma cell proliferation and invasion. IGF­1R was confirmed as a direct target gene of miR­186. In addition, the mRNA expression of IGF­1R was upregulated and inversely correlated with that of miR­186 in glioma tissues. The effects of IGF­1R­knockdown on glioma cell proliferation and invasion were similar to the effects induced by the overexpression of miR­186. These findings demonstrated that miR­186 acted as a tumor suppressor by targeting IGF­1R in glioma, suggesting miR­186 may be a potential therapeutic target for the treatment of this disease.

Overexpression of Protease Serine 8 Inhibits Glioma Cell Proliferation, Migration, and Invasion via Suppressing the Akt/mTOR Signaling Pathway.

Protease serine 8 (PRSS8), a serine peptidase, has a widespread expression in normal epidermal cells. Recently, many researchers demonstrated downregulation of PRSS8 in cancer tissues as well as its tumor suppressor role in cancer development. However, the biological functions of PRSS8 in glioma remain unclear. In the current study, we demonstrated a decreased expression of PRSS8 in glioma tissues and cell lines. PRSS8 upregulation inhibited glioma cell proliferation, migration, and invasion. In addition, xenograft experiments showed that PRSS8 overexpression suppressed glioma cell growth in vivo. We also found that upregulated PRSS8 reduced the protein expression levels of p-Akt and p-mTOR in glioma cells. Taken together, our study demonstrated that overexpression of PRSS8 inhibited glioma cell proliferation, migration, and invasion via suppressing the Akt/mTOR signaling pathway. Therefore, PRSS8 may act as a novel therapeutic target for glioma.

Attention dysfunction of postoperative patients with glioma.

BACKGROUND: Attention dysfunction has been observed among many kinds of nervous system diseases, including glioma. This study aimed to investigate the correlation between glioma localization, malignancy, postoperative recovery time and attention deficit. METHODS: A total of 45 patients with glioma who underwent surgical resection and 18 healthy volunteers were enrolled. The attention network test, digital span test, color trail test II and Stroop test were used to detect the characteristics of attention deficit. RESULTS: Orientation network dysfunction was detected in the parietal lobe tumor group, and execution network deficit was detected in both the frontal and parietal lobe groups, while no significant difference was detected in the temporal lobe group compared to healthy controls. The high-grade glioma group (grade III-IV) exhibited more serious functional impairment than the low-grade group (grade I-II). No significant correlation was observed between postoperative recovery time and attention impairment. CONCLUSIONS: High-grade glioma patients suffer more severe attention impairment. In addition, the frontal and parietal lobe glioma patients suffer attention dysfunction in dissimilar manner. These findings will provide important guidance on the care of glioma patients after therapy.

Hyperbaric oxygen treatment and enteral nutrition support with glutamine relieves traumatic brain injury in the rats.

The abnormal metabolic processes following traumatic brain injury (TBI) have been proposed to contribute to secondary injuries after TBI. Therefore, enteral nutrition (EN) support for TBI patients has received more attention. This study aimed to evaluate the complimentary effects of enteral nutrition with glutamine and hyperbaric oxygen (HBO) on the recovery of TBI. TBI model was established in SD rats, which were randomly divided into four groups: TBI, TBI + HBO, TBI + GLN, and TBI + HBO + GLN. Neuronal apoptosis in penumbra area was detected by TUNEL. Serum prealbumin level was detected by ELISA. Motor function was evaluated by beam-balance test. We found that the body weight of the rats had no significant differences in different groups before and after injury. Among the four groups, beam-balance test score was the lowest, serum prealbumin level was the highest, and neuronal apoptosis rate was the lowest in TBI + HBO + GLN group on day 3 and 7 after TBI. In conclusion, our data suggest that hyperbaric oxygen combined with enteral nutrition support with glutamine is effective in reducing neuronal apoptosis, increasing serum prealbumin concentration and improving neurological function after TBI injury.