Doxorubicin-loaded nanoparticle coated with endothelial cells-derived exosomes for immunogenic chemotherapy of glioblastoma.

Treatments of glioblastoma (GBM) have not been very effective, largely due to the inefficiency of drugs in penetrating the blood brain barrier (BBB). In this study, we investigated the potential of exosome-coated doxorubicin (DOX)-loaded nanoparticles (ENPDOX) in BBB penetration, inducing immunogenic cell death (ICD) and promoting survival of GBM-bearing mice. DOX-loaded nanoparticles (NPDOX) were coated with exosomes prepared from mouse brain endothelial bEnd.3 cells. ENPDOX cellular uptake was examined. Penetration of ENPDOX through the BBB was tested in an in vitro transwell system and a GBM mouse model. The effects of ENPDOX in inducing apoptosis and ICD were assessed. Finally, the efficacy of ENPDOX in the treatment of GBM-bearing mice was assessed. ENPDOX was taken up by bEnd.3 cells and could penetrate the BBB both in vitro and in vivo. In vitro, ENDDOX induced apoptosis and ICD of glioma GL261 cells. Systemic administration of ENPDOX resulted in maturation of dendritic cells, activation of cytotoxic cells, altered production of cytokines, suppressed proliferation and increased apoptosis of GBM cells in vivo and prolonged survival of GBM-bearing mice. Our findings indicate that ENPDOX may be a potent therapeutic strategy for GBM which warrants further investigation in clinical application.

Exogenous CGRP Regulates Apoptosis and Autophagy to Alleviate Traumatic Brain Injury Through Akt/mTOR Signalling Pathway.

With millions of traumatic brain injury (TBI) patients every year, TBI is regarded as one of the leading causes of human death and disability. Calcitonin gene-related peptide (CGRP) has been domenstrated to be a potential therapeutic target for TBI. However, the detailed effect and underlying mechanism of CGRP on the injured brain after TBI has hardly been investigated. In this work, we established TBI models of mice and injected CGRP before and after modelling to study its effects on the brain lesion, neurological functions and behaviours, neuron apoptosis and autophagy after TBI. Impacts of introduced CGRP on the activation of Akt/mTOR signalling in the cortical tissues surrounding injured areas after TBI were also evaluated. It was found that CGRP was reduced after TBI, and gradually restored over time. CGRP administration significantly restored the brain lesion induced by TBI. The permeability of blood-brain barrier and brain edema was increased dramatically after TBI, which was ameliorated by exogenous CGRP. Moreover, several neurological behaviour tests were performed, showing that CGRP introduction also relieved the cognitive abilities of mice which were impaired after TBI. Enhancing apoptosis and autophagy of neurons in the cortical tissues of injury sites following TBI were also alleviated by CGRP administration. Besides, CGRP-treated brain cortical tissues showed increased activation of Akt/mTOR signalling after TBI. Therefore, the results suggest that exogenous CGRP plays a neuroprotective role in the injuryed brain after TBI, to relieve cell apoptosis and autophagy, at least partially through Akt/mTOR signalling pathway. This finding also provides more evidence for the treatment of TBI through introducing exogenous CGRP or its related drugs.

Omega-3 Polyunsaturated Fatty Acids Alleviate Traumatic Brain Injury by Regulating the Glymphatic Pathway in Mice.

Background: The glymphatic pathway has been shown to be impaired in traumatic brain injury (TBI). Omega-3 polysaturated fatty acids (Omega-3, PUFAs) are involved in the clearance of amyloid-ß through the glymphatic system and this effect is Aquaporin-4 (AQP4) dependent. We hypothesize that Omega-3 PUFAs can alleviate neurological impairment in TBI by protecting the glymphatic pathway. Methods: We pretreated mice with Omega-3 PUFAs rich fish oil and introduced TBI in the mice. Neurological functions were assessed through the modified neurological severity score (mNSS) system and Rota-rod test. Aß42 levels and radioisotope clearance were examined to determine the function of glymphatic system. AQP4 protein and mRNA expressions and its polarity were examined in fish oil treated TBI mice or control mice. Finally, the integrity of blood-brain barrier was determined by Evans blue extravasation and measurement of tight junction proteins (ZO-1 and Occludin) levels. Results: TBI surgery induced significant neurological functional impairment, Omega-3 PUFAs attenuated TBI-induced neurological impairment, as evidenced by reduced mNSS, improved performance in the Rota-rod test. Furthermore, Omega-3 PUFAs improved glymphatic clearance after induction of TBI in mice, reduced Aß42 accumulation, partially restored the clearance of both 3H-mannitol and 14C-Inulin. Omega-3 PUFAs also suppressed AQP4 expression and partially prevented loss of AQP4 polarity in mice undergoing TBI. Finally, Omega-3 PUFAs protected mice from TBI induced blood-brain barrier disruption. Conclusion: Omaga-3 PUFAs attenuate neurological function by partially restoring the AQP4 dependent glymphatic system in mice with TBI.

The potential role of vascular endothelial growth factor as a new biomarker in severe intracerebral hemorrhage.

BACKGROUND: We studied the association between high serum levels of vascular endothelial growth factor (VEGF) and clinical outcomes of intracerebral hemorrhage (ICH) patients. METHODS: Patients were divided into group A (<20 mL), group B (20-30 mL), and group C (>30 mL) based on the bleeding amount. ICH patients were also categorized into the mild group, moderate group (16-30), and severe group (31-45) based on the National Institutes of Health Stroke Scale (NIHSS). The serum levels of VEGF in acute ICH patients detected at 24, 48, and 72 hours were obtained using ELISA kit, and then compared with control group. Main clinical outcomes were evaluated using the modified Rankin scale at 90 days. RESULTS: The serum levels of VEGF were significantly higher than those in the control group. The serum levels of VEGF in group C were specifically higher compared with those in other two groups. The severe group exhibited higher levels of VEGF than the other two groups. NIHSS scores in patients with good outcomes were lower than those with poor outcomes. Besides, VEGF levels in patients with good outcomes were much higher than those in patients with poor outcomes. ROC results indicated that the optimal cut-off value of VEGF at 72 hours for predicting good outcomes was 111.17 pg/mL with 91.5 sensitivity, 98.7 specificity, and an AUC of 0.952 Our results showed that higher serum levels of VEGF were associated with process of ICH. CONCLUSION: VEGF could be a new marker in ICH for severity.

Diabetes mitigates the recovery following intracranial hemorrhage in rats.

Intracranial hemorrhage (ICH) is a common subtype of stroke with high morbidity and mortality. However, few studies have examined the effects of diabetes on the recovery from ICH-induced brain injury. Therefore, we examined the effects of diabetes on protein levels of aquaporins, neuronal loss, angiogenesis, blood brain barrier (BBB) integrity, and neurological deficits following intra-DH collagenase-induced ICH in the hippocampus. We found that diabetic rats exhibited enhanced AQP9 expression in the hippocampus relative to non-diabetic rats, which was associated with increased behavioral deficits. Additionally, ICH induced neovascularization, proliferation of brain microvascular endothelial cells, and hippocampal neuronal loss. However, ICH-induced neovascularization and proliferation of brain microvascular endothelial cells was severely impaired in diabetic rats. Furthermore, ICH-induced hippocampal neuronal loss was exaggerated in diabetic rats. Finally, ICH impaired BBB integrity in the ipsilateral hemisphere, which was increased in diabetic rats. Taken together, the attenuated brain angiogenesis, increased hippocampal neuronal loss, and impaired BBB integrity in diabetic rats after ICH were associated with enhanced AQP9 expression. This may suggest that AQP9 is one of the underlying mechanisms that can mitigate the recovery from ICH in diabetic populations.

Functionalized graphene oxide as a drug carrier for loading pirfenidone in treatment of subarachnoid hemorrhage.

Subarachnoid hemorrhage (SAH) is a life-threatening disease that causes high morbidity and mortality. Pirfenidone is a SAH drug that prevents secondary bleeding and cerebral infarction. To improve its therapeutic efficacy, this study aimed to employ a functionalized graphene oxide nanosheet (FGO) as a drug carrier loading pirfenidone to treat SAH. The graphene oxide nanosheet was introduced with transcription activator peptide (Tat), followed by functionalization with methoxy polyethylene glycol (mPEG) and loading with pirfenidone. The pirfenidone-loaded FGO (pirfenidone-FGO) exhibits better treatment efficacy than the single pirfenidone due to more effective loading and controlled release of the drug in tissue. The introduction of Tat and mPEG onto GO nanosheet contributes to the ability to cross the blood-brain barrier and the stability in blood circulation of the drug. At lower pH values, the highly efficient release of the drug from the pirfenidone-FGO exerts effective treatment to acidic inflammatory lesion after severe SAH. Besides its treatment function, FGO is also shown as a strong near infrared absorbing material which can be applied in photoacoustic imaging, allowing rapid real-time monitoring with deep resolution of brain tissues after SAH. The treatment efficacy of pirfenidone-FGO for central nervous system injuries is further demonstrated by hematoxylin and eosin staining of coronal brain slices, as well as measurements of brain water content and blood-brain barrier permeability. Our study supports the potential of FGO in clinical application in treatment of SAH.

A novel technology: percutaneous injection of fibrin glue as a treatment for frontal sinus cerebrospinal fluid rhinorrhea.

In this study, we examined the effectiveness of percutaneous injected fibrin glue as a treatment for frontal sinus cerebrospinal fluid (CSF) rhinorrhea in a series of 4 cases. All 4 patients had fracture in the posterior wall of the frontal sinus. The anterior wall of the frontal sinus was punctured following high-resolution computed tomography imaging. In 3 out of 4 patients with defective skull due to prior frontal craniotomy, direct percutaneous puncture of the frontal sinus was used. Fibrin glue was injected to close the fistula and to seal the rhinorrhea. Surgery procedures lasted for 15-35 minutes (average 27.6 min). Rhinorrhea was stopped in all patients after the surgery, with no recurrence at a 10-month follow-up visit. In 1 case, the glue was expelled by coughing at 2 days after the surgery but was completely stopped with no recurrence after a second attempt. One patient with no recurrence at a 10-month follow-up died of tumor relapse at 12 months. In summary, fibrin glue could be used as a novel treatment for frontal sinus CSF rhinorrhea.