A promising frontier: targeting NETs for stroke treatment breakthroughs.

Stroke is a prevalent global acute cerebrovascular condition, with ischaemic stroke being the most frequently occurring type. After a stroke, neutrophils accumulate in the brain and subsequently generate and release neutrophil extracellular traps (NETs). The accumulation of NETs exacerbates the impairment of the blood‒brain barrier (BBB), hampers neovascularization, induces notable neurological deficits, worsens the prognosis of stroke patients, and can facilitate the occurrence of t-PA-induced cerebral haemorrhage subsequent to ischaemic stroke. Alternative approaches to pharmacological thrombolysis or endovascular thrombectomy are being explored, and targeting NETs is a promising treatment that warrants further investigation.

FBXO31 suppresses lipogenesis and tumor progression in glioma by promoting ubiquitination and degradation of CD147.

Glioma is the most frequent tumor occurred in brain and spinal cord with a high mortality and morbidity. This study aimed to explore the effects of FBXO31 on lipid synthesis and tumor progression in glioma. The expression of FBXO31 was low in glioma tissues and cell lines, which indicated poor prognosis in glioma patients. Overexpression of FBXO31 accelerated ubiquitination and degradation of CD147, which downregulated the expression of SREBP1c. In addition, overexpression of FBXO31 resulted in the reduction of lipogenesis through suppressing the activation of AKT/mTOR signaling axis, thus preventing the tumor growth and aggressiveness in glioma. These results provided a new cognition to pathology of glioma and new therapeutic targets for treating glioma in future.

Erythrocyte Fraction in Thrombi Is Increased with Serum Iron by Influencing Fibrin Networks via Oxidative Stress.

OBJECTIVE: This study investigated whether the erythrocyte fraction in thrombi would be increased with serum iron via oxidative stress. METHODS: This study retrospectively enrolled patients with acute ischemic stroke treated using endovascular treatment in a single stroke center from October to December 2019. We examined the relationship between serum iron and erythrocyte-rich thrombi and the correlation of serum iron and the erythrocyte fraction in thrombi using clinical samples. Experiments in vivo and in vitro were performed to investigate the influence of oxidative stress on the correlation between serum iron concentration and erythrocyte fraction in thrombi. RESULTS: We found from the clinical samples that serum iron concentration was related to erythrocyte-rich thrombi and positively associated with the erythrocyte fraction in thrombi in vivo. Further, the tightness of the fibrin networks regulating the erythrocyte fraction in thrombi was increased with serum iron concentration in vivo. Additionally, the oxidative stress level was increased with serum iron concentration in vivo. Moreover, we found that the tightness of the fibrin networks increased with higher oxidative stress levels in vitro. Lastly, experiments in vivo with inhibiting oxidative stress showed that the erythrocyte fraction in thrombi and the tightness of fibrin networks significantly increased in the iron group than those in the iron with oxidative stress inhibitor group and control group. CONCLUSIONS: Oxidative stress played a role in the process that the erythrocyte fraction in thrombi was increased with serum iron by influencing fibrin networks.

Erythrocyte-rich thrombi related to serum iron contribute to single stent retrieval and favorable clinical outcomes in acute ischemic stroke by endovascular treatment.

BACKGROUND: Erythrocyte-rich thrombi seem to be associated with favorable clinical outcomes of patients with AIS by endovascular treatment (EVT), as observed from previous studies. However, only few studies show whether erythrocyte-rich thrombi can be associated with favorable clinical outcomes by EVT and which factor can be related to erythrocyte-rich thrombi. This retrospective study aimed to evaluate the relationship between erythrocyte-rich thrombi and favorable clinical outcomes and further explored factors associated with erythrocyte-rich thrombi. METHODS: This study was carried out retrospectively from March 2016 to April 2019 on patients who suffered acute ischemic stroke and were treated by EVT at this stroke center. The laboratory test and clinical data were assessed for the relationship between erythrocyte-rich thrombi and favorable clinical outcomes and factors associated with erythrocyte-rich thrombi. All thrombi were divided into erythrocyte-rich thrombi group and fibrin-rich thrombi group based on the proportion of area of the predominant composition which was more than 50% in retrieved thrombi. RESULTS: This retrospective study enrolled 84 patients, including 32 patients in the erythrocyte-rich thrombi group and 52 patients in the fibrin-rich thrombi group. It showed single stent retrieval (p = 0.017, adjusted OR: 4.061, 95% CI: 1.281-12.872) and favorable clinical outcomes (p < 0.001, adjusted OR: 14.648, 95% CI: 4.637-46.270) were both significantly associated with erythrocyte-rich thrombi. A significant difference in the factor associated with erythrocyte-rich thrombi was serum iron, which correlated positively with erythrocyte fraction in thrombi (p < 0.001, r: 0.452). CONCLUSIONS: Erythrocyte-rich thrombi could contribute to single stent retrieval and favorable clinical outcomes by EVT, and serum iron might be the factor associated with erythrocyte-rich thrombi.

MiR-134, epigenetically silenced in gliomas, could mitigate the malignant phenotype by targeting KRAS.

Gliomas are characterized by a malignant phenotype with proliferation, cell cycle arrest and invasion. To explore the biological consequences of epigenetically regulated miRNAs, we performed a microarray-based screening (whose expression was affected by 5-AZA treatment) followed by bisulfite sequencing validation. We found that miR-134 as an epigenetically regulated suppressor gene with prognostic value in gliomas. MicroRNA-134 was downregulated in high-grade gliomas, especially in GBM samples. Functional studies in vitro and in vivo in mouse models showed that overexpression of miR-134 was sufficient to reduce cell cycle arrest, cell proliferation and invasion. Target analysis and functional assays correlated the malignant phenotype with miR-134 target gene KRAS, an established upstream regulator of ERK and AKT pathways. Overall, our results highlighted a role for miR-134 in explaining the malignant phenotype of gliomas and suggested its relevance as a target to develop for early diagnostics and therapy.

Modulation of Pulmonary Vascular Remodeling in Hypoxia: Role of 15-LOX-2/15-HETE-MAPKs Pathway.

BACKGROUND: We have previously shown that 15-hydroxyeicosatetraenoic acid (15-HETE) plays a critical role in pulmonary hypertension (PH)-associated vascular remodeling. However, the signaling mechanisms remain unclear. The purpose of this study was to investigate the role of 15-lipoxygenase-2 (15-LO-2)/15-HETE-mitogen-activated protein kinases (MAPKs) pathway in hypoxia-induced pulmonary vascular remodeling and the underlying mechanisms. METHODS: The arterial wall thickness was measured by hematoxylin and eosin (HE) staining in distal pulmonary arteries isolated from normal and PAH patient-derived lungs. The protein expression of phosphorylated extracellular signal-regulated kinase (p-ERK) and phosphorylated p38 mitogen-activated protein kinases (p-p38MAPK) were measured by Western blot in the lungs of PAH patients and hypoxia-induced rats. The apoptosis of cultured rat pulmonary arterial smooth muscle cells (PASMCs) was determined by Terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) and Flow cytometry. The cell proliferation and cell cycle in PASMCs following hypoxia were analyzed by bromodeoxyuridine incorporation and flow cytometry, respectively. RESULTS: Our results showed that the levels of p-ERK and p-p38MAPK were both drastically elevated in lungs from human patients and hypoxic rats. The HE staining revealed that the medial wall thickness was higher in patients with PAH than normal humans. In cultured PASMCs, Hypoxia stimulated the cell proliferation, the cell cycle progression, and subsequently promoted cell differentiation and cell migration leading to the suppressed cell apoptosis. Furthermore, MAPKs- induced cell proliferation and anti-apoptosis in PASMCs is 15-LO-2/15HETE activation-dependent. CONCLUSION: Our study indicates that hypoxia-induced pulmonary vascular remodeling is associated with increased levels of 15-LO-2 and 15-HETE. 15-LO-2/15-HETE stimulates the cell proliferation and anti-apoptosis in PASMCs through phosphorylation of ERK and p38MAPK, which subsequently contributing to hypoxia-induced pulmonary vascular remodeling.

Liposomes modified with P-aminophenyl-α-D-mannopyranoside: a carrier for targeting cerebral functional regions in mice.

Targeting of intracerebral functional regions has been limited by the inability to transport drugs across the blood-brain barrier (BBB) and by poor accumulation in these regions. To overcome these hurdles, liposomes modified with P-aminophenyl-α-d-mannopyranoside (MAN) were used as a fluorescent dye carrier through the BBB and used the specific distribution of liposomes (LIP) modified with MAN (MAN-LIP) to target various functional regions of the brain. An in vitro BBB model was established to evaluate the transendothelial ability of MAN-LIP, and liposomes uptake by C6 glioma cells was analyzed by flow cytometry and live cell imaging. Liposome targeting was evaluated using in vivo and ex vivo imaging. After MAN-LIP administration, the transendothelial ability and the delivery of fluorescent dye to the brain significantly increased. MAN-LIP concentrated in the cortex at 4 h, shifting distribution to the cerebellum and brainstem at 12 h. The fluorescence intensity in the hippocampus and pontine nuclei remained high and stable over a period of 12 h. The results demonstrate that MAN-LIP is able to enhance cellular uptake in vitro and also promotes penetration through the BBB and accumulation in the brain with a distinct spatio-temporal pattern.

Pifithrin-α enhances the survival of transplanted neural stem cells in stroke rats by inhibiting p53 nuclear translocation.

AIMS: To examine a novel strategy to enhance the survival of grafted neural stem cells (NSCs) in stroke model. METHODS: Using a cell counting kit-8 (CCK-8) and TUNEL assay to test the protective effects of p53 inhibitor, pifithrin-α (PFT-α), on oxygen glucose deprivation (OGD) in NSCs. We compared the effects of vehicle + NSCs and FFT-α + NSCs on the efficacy of transplantation in stroke rat model using behavioral analysis, immunohistochemistry, etc. RESULTS: Pifithrin-α increased viability and decreased apoptosis in NSCs after OGD in vitro. By in vivo studies, we showed that the best recovery of neurological function in the stroke rats and the maximum survival of grafted NSCs were found in the PFT-α + NSCs group. Twelve hours after cell transplantation, p53 was localized to the nuclei of grafted NSCs in the vehicle + NSCs group but was primarily localized to the cytoplasm in the PFT-α + NSCs group. The p53-upregulated modulator of apoptosis (PUMA) was highly expressed among the grafted cells in the vehicle + NSCs group compared with that in the PFT-α + NSCs group. CONCLUSION: Our results indicate that PFT-α enhances the survival of grafted NSCs through the inhibition of p53 translocation into the nucleus.

The liposomal daunorubicin plus tamoxifen: improving the stability, uptake, and biodistribution of carriers.

The synergistic effects of tamoxifen on the sensitivity of MCF-7 cells to daunorubicin have been reported. Whether the effects of daunorubicin on MCF-7/adr cells can be improved by tamoxifen in liposomes and how tamoxifen changes daunorubicin's behavior in vivo remains unclear. The aim of this study was to investigate the effects of tamoxifen on the uptake and biodistribution of daunorubicin liposomes by breast-cancer-resistant MCF-7/adr cells in vitro and in vivo. The uptake of liposomes by MCF-7/adr cells in vitro studies was measured using flow cytometry and laser confocal microscopy. The biodistributions of carriers and free drugs were evaluated by DiR dye using in vivo imaging. Tamoxifen obviously enhanced the cellular uptake of liposomes by MCF-7/adr cells in time-dependent manners. According to the results from in vivo imaging analysis, the mean fluorescence intensity of DiR liposomes with tamoxifen in the tumor regions of MCF-7/adr tumor-bearing nude mice was much stronger than that of DiR liposomes alone (16,450 ± 1,331 versus 3,666 ± 321; n = 3). Pegylated liposomes elongated the existence of daunorubicin in the circulatory system and the enhanced permeability and retention effect enhanced its concentration in local tumor tissues, which may provide the precondition for tamoxifen further promoting the uptake by MCF-7/Adr cells in vivo. Using daunorubicin liposomes and tamoxifen together generates better biodistribution profiles in tumor tissue than using daunorubicin liposomes only, which contributes to improving the therapeutic effect of breast cancer treatment.