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Background: Previous randomised trials have shown an overwhelming benefit of mechanical thrombectomy for treating patients with stroke caused by large vessel occlusion of the anterior circulation. Whether endovascular treatment is beneficial for vertebrobasilar artery occlusion remains unknown. In this study, we aimed to investigate the safety and efficacy of endovascular treatment of acute strokes due to vertebrobasilar artery occlusion.Methods: We did a multicentre, randomised, open-label trial, with blinded outcome assessment of thrombectomy in patients presenting within 8 h of vertebrobasilar occlusion at 28 centres in China. Patients were randomly assigned (1:1) to endovascular therapy plus standard medical therapy (intervention group) or standard medical therapy alone (control group). The randomisation sequence was computer-generated and stratified by participating centres. Allocation concealment was implemented by use of sealed envelopes. The primary outcome was a modified Rankin scale (mRS) score of 3 or lower (indicating ability to walk unassisted) at 90 days, assessed on an intention-to-treat basis. The primary safety outcome was mortality at 90 days. Secondary safety endpoints included the rates of symptomatic intracranial haemorrhage, device-related complications, and other severe adverse events. The BEST trial is registered with ClinicalTrials.gov, NCT02441556.Findings: Between April 27, 2015, and Sept 27, 2017, we assessed 288 patients for eligibility. The trial was terminated early after 131 patients had been randomly assigned (66 patients to the intervention group and 65 to the control group) because of high crossover rate and poor recruitment. In the intention-to-treat analysis, there was no evidence of a difference in the proportion of participants with mRS 0-3 at 90 days according to treatment (28 [42%] of 66 patients in the intervention group vs 21 [32%] of 65 in the control group; adjusted odds ratio [OR] 1·74, 95% CI 0·81-3·74). Secondary prespecified analyses of the primary outcome, done to assess the effect of crossovers, showed higher rates of mRS 0-3 at 90 days in patients who actually received the intervention compared with those who received standard medical therapy alone in both per-protocol (28 [44%] of 63 patients with intervention vs 13 [25%] of 51 with standard therapy; adjusted OR 2·90, 95% CI 1·20-7·03) and as-treated (36 [47%] of 77 patients with intervention vs 13 [24%] of 54 with standard therapy; 3·02, 1·31-7·00) populations. The 90-day mortality was similar between groups (22 [33%] of 66 patients in the intervention vs 25 [38%] of 65 in the control group; p=0·54) despite a numerically higher prevalence of symptomatic intracranial haemorrhage in the intervention group.Interpretation: There was no evidence of a difference in favourable outcomes of patients receiving endovascular therapy compared with those receiving standard medical therapy alone. Results might have been confounded by loss of equipoise over the course of the trial, resulting in poor adherence to the assigned study treatment and a reduced sample size due to the early termination of the study.Funding: Jiangsu Provincial Special Program of Medical Science. [ABSTRACT FROM AUTHOR]

Background. Our previous studies indicated that the increased arginine vasopressin(AVP) in ischemic brain regions of gerbils could exacerbate the ischemic brian edema. This experiments is further clarify the relation between AVP and cerebral ischema at the molecular level. Methods. The contents of AVP, AVP mRNA, AVP immunoreactive (ir) neurons in supraoptic nucleus (SON) and paraventricular nucleus (PVN) after cerebral ischema and reperfusion were respectively determined by radioimmunoassay (RIA), immunocytochemistry (II C), situ hibridization and computed image pattern analysis. Results. The contents of AVP in SON, PVN were increased, and the AVP ir positive neurons in SON and PVN were also significantly increased as compared with the controls after ischema and reperfusion. And there were very light staining of AVP ir positive neurons in the other brain areas such as suprachiasmatic nucleus (SC) and periventricular hypothalamine nucleus (PE), but these have no significant changes as compared with the controls. During different periods of cerebral ischema (30-120 min) and reperfussion (30 min), AVP mRNA expression in SON and PVN were more markedly increased than the controls. Conclusions. The transcription of AVP gene elevated, then promoting synthesis and release of AVP in SON, PVN. Under the specific condition of cerebral ischema and reperfussion, the activity and contents of central AVP increased abnormally is one of the important factors which causes ischema brain damage. [ABSTRACT FROM AUTHOR]

Background: Neuroinflammation is a vital pathophysiological process during ischemic stroke. Activated astrocytes play a major role in inflammation. Lipocalin-2 (LCN2), secreted by activated astrocytes, promotes neuroinflammation. Pyroptosis is a pro-inflammatory form of programmed cell death that has emerged as a new area of research in stroke. Nevertheless, the potential role of LCN2 in astrocyte pyroptosis remains unclear. Methods: An ischemic stroke model was established by middle cerebral artery occlusion (MCAO) in vivo. In this study, in vitro, oxygen–glucose deprivation and reoxygenation (O/R) were applied to cultured astrocytes. 24p3R (the LCN2 receptor) was inhibited by astrocyte-specific adeno-associated virus (AAV-GFAP-24p3Ri). MCC950 and Nigericin sodium salt (Nig) were used to inhibit or promote the activation of NLRP3 inflammasome pharmacologically, respectively. Histological and biochemical analyses were performed to assess astrocyte and neuron death. Additionally, the neurological deficits of mice were evaluated. Results: LCN2 expression was significantly induced in astrocytes 24 h after stroke onset in the mouse MCAO model. Lcn2 knockout (Lcn2−/−) mice exhibited reduced infarct volume and improved neurological and cognitive functions after MCAO. LCN2 and its receptor 24p3R were colocalized in astrocytes. Mechanistically, suppression of 24p3R by AAV-GFAP-24p3Ri alleviated pyroptosis-related pore formation and the secretion of pro-inflammatory cytokines via LCN2, which was then reversed by Nig-induced NLRP3 inflammasome activation. Astrocyte pyroptosis was exacerbated in Lcn2−/− mice by intracerebroventricular administration of recombinant LCN2 (rLCN2), while this aggravation was restricted by blocking 24p3R or inhibiting NLRP3 inflammasome activation with MCC950. Conclusion: LCN2/24p3R mediates astrocyte pyroptosis via NLRP3 inflammasome activation following cerebral ischemia/reperfusion injury. [ABSTRACT FROM AUTHOR]

Ferroptosis is a form of non-apoptotic cell death caused by iron-dependent peroxidation of lipids. It contributes to ischemic stroke-induced neuronal damage. Elabela (ELA), a novel endogenous ligand for Apelin receptor (APJ), regulates oxidative stress and exerts a protective role in cardiovascular disease. However, the effect of ELA-APJ axis on cellular ferroptosis in cerebral ischemia/reperfusion (I/R) remains elusive. The present study showed that ELA and APJ were expressed on neurons and increased after cerebral I/R injury. The I/R insult triggered typical molecular and morphological features of neuronal ferroptosis, including iron and MDA accumulation, mitochondrial shrink and membrane rupture, upregulation of positive ferroptosis regulators and downregulation of negative regulators. ELA-32 treatment reduced brain infarction and ameliorated neurobehavioral deficits and cognitive dysfunction. Moreover, ELA-32 administration alleviated neuronal ferroptosis, accompanied by reduced iron deposition, decreased mitochondrial damage, relived lipid peroxidation and glutathione reduction. Such effects of ELA-32 were abolished by AAV-APJ-RNAi or nuclear factor erythroid 2-related factor 2 (NRF2) inhibitor ML385. Mechanistically, ELA was shown to bind to APJ and activate NRF2/ARE anti-oxidative signaling pathway via Gα13. Together, these findings suggested that ELA-APJ axis mitigates neuronal ferroptosis after ischemic stroke and that the ELA-32 peptide may be a putative therapeutic avenue for ischemic stroke. [Display omitted] • Ischemic stroke induces Elabela and APJ expression and neuronal ferroptosis. • Activation of APJ with ELA-32 ameliorates ischemia/reperfusion injury and cognitive dysfunction. • Treatment with ELA-32 reduces neuronal lipid peroxidation and ferroptosis via NRF2/ARE signaling pathway. • Elabela binds to APJ and subsequently triggers NRF2-mediated anti-oxidative response through Gα13. [ABSTRACT FROM AUTHOR]

• Culture medium from OGD preconditioned astrocytes ameliorates OGD-induced neuron injury. • Exosomes derived from preconditioned astrocytes can be internalized into neurons. • OGD preconditioning promotes the production of exosomal miR-92b-3p from astrocytes. • MiR-92b-3p mimic as same as exosomes from preconditioned astrocytes exerts protective effects on neurons after OGD. Ischemic preconditioning (IPC) exerts protective effects against ischemic cerebral injury. In the present study, an in vitro model of cerebral ischemia (oxygen and glucose deprivation, OGD) was established to investigate the neuroprotective mechanism of IPC. We found that conditioned medium (C.M.) from astrocytes rather than neurons nor microglia cell line BV2 exerted neuroprotection. Moreover, exosomes derived from OGD preconditioned astrocytes can be taken up by neurons and attenuated OGD-induced neuron death and apoptosis. High-throughput microRNA (miRNA) sequencing revealed that miR-92b-3p levels in exosomes released from preconditioned astrocytes were increased. Overexpression of miR-92b-3p in neurons with miR-92b-3p mimic achieved the same protective effects as C.M. from astrocytes. Thus, we propose that the mechanism of IPC may associate with astrocytes, and that exosome-mediated miR-92b-3p shuttle from preconditioned astrocytes to neurons participate in these process. [ABSTRACT FROM AUTHOR]

Background Inflammation and neutrophils play pivotal roles in hemorrhagic transformation (HT) after recombinant tissue plasminogen activator (rtPA) treatment in stroke; however, the contribution of Nod-like receptor protein 3 (NLRP3), a key component of the innate immune system, is not yet known. This study aimed to explore the role of NLRP3 in the delayed rtPA-induced HT and its association with the neutrophil recruitment. Methods Rats were subjected to thromboembolic focal cerebral ischemia and delayed rtPA treatment at 4 h after ischemia to mimic HT. NLRP3 short hairpin RNAs (shRNA) were administered 72 h before ischemia. Additionally, rabbit anti-rat neutrophil serum (inducing neutropenia) was administered before cerebral ischemia. The infarct volume, edema volume, neurological deficit, hemorrhages, blood-brain barrier (BBB) integrity and brain neutrophil recruitment were evaluated at 24 h after cerebral ischemia. Results Our results demonstrated that delayed rtPA treatment at 4 h after ischemia promoted the expression of NLRP3 in neurons, microglia and endothelial cells, degradation of BBB components, and HT. NLRP3 knockdown significantly attenuated NLRP3 expression, BBB disruption, and HT. It also improved neurological functions and reduced neutrophil recruitment. Rabbit anti-rat neutrophil serum, like NLRP3 shRNA, reduced hemorrhage score and hemorrhage volumes after rtPA treatment. Furthermore, the anti-rat neutrophil serum combined with NLRP3 shRNA didn't further increase the protective effect on HT compared to rabbit anti-rat neutrophil serum used alone. Conclusions Together, our data suggest that NLRP3 inhibition can reduce neutrophil recruitment, which may contribute to the inhibitory effect on HT. [ABSTRACT FROM AUTHOR]

Bradykinin receptors play important roles in cerebral ischaemia-reperfusion (I/R) injury of non-diabetics. Their functions in diabetics, however, have not been studied. In this study, we hypothesized that bradykinin 1 receptor (B1R) and bradykinin 2 receptor (B2R) would be upregulated and participate in the regulation of diabetic ischaemic stroke. To investigate this, we first evaluated B1R and B2R expression at different time points after I/R in non-diabetic and diabetic rats (Sprague-Dawley) by using real-time quantitative reverse transcription polymerase chain reaction, western blotting, and immunofluorescence. Then, pharmacological inhibitors were separately administered via the tail vein to analyse their effects on cerebral ischaemia in diabetics. Both receptors were significantly upregulated after cerebral I/R in non-diabetic and diabetic rats. B1R expression in diabetic rats increased in a sharper manner than in non-diabetic rats, whereas B2R expression increased to the same level during the early stage of reperfusion but later became lower. Interestingly, the upregulated B1R was expressed in astrocytes, whereas B2R was mainly located in neurons in the ischaemic penumbra. Functional studies showed that inhibition of B1R significantly reduced infarct volume, neurological deficits, cell apoptosis, and neuron degeneration, probably by attenuating blood-brain barrier (BBB) disruption and postischaemic inflammation, at 24 h after reperfusion. In contrast, B2R antagonist had opposite effects, and exacerbated BBB penetrability and tissue inflammation. These findings suggest that B1R and B2R have detrimental and beneficial effects, respectively in diabetic cerebral ischaemia, which might open new avenues for the treatment of ischaemic stroke in diabetic patients through selective pharmacological blockade or activation. [ABSTRACT FROM AUTHOR]

Bax interacting factor-1 (Bif-1), a multifunctional protein, can regulate cell apoptosis and autophagy. Up-regulation of Bif-1 expression has been associated with neuronal survival. Moreover, several studies have reported that Bif-1 is involved in ischemic stroke. However, the specific function of Bif-1 in cerebral ischemia-reperfusion (I/R) injury is not well understood. The aim of this study is to expose the potential protective effect of Bif-1 against cerebral I/R injury and its related mechanism. In the current study, we showed that adenovirus-mediated Bif-1-overexpression promoted oxygen and glucose deprivation followed by reperfusion (OGD/R)-treated cortical neurons' survival and reduced the cell apoptotic rate. We found that caspase-3 activity was inhibited by Bif-1 overexpression. In addition, we observed that Bif-1 overexpression induces cell autophagy, and the autophagy-specific inhibitor 3-Methyladenine (3-MA) attenuates cell survival. Interestingly, knockdown of Bif-1 resulted in attenuation of neuron survival, promotion of cell apoptosis and suppression of cell autophagy in neurons. In addition, knockdown of Bif-1 inhibited ERK1/2 activation. Our observations implicated Bif-1 as a novel target of cerebral I/R injury and played a neuroprotective effect via promoting cell survival and reducing apoptosis. [ABSTRACT FROM AUTHOR]

Vascular endothelial growth factor (VEGF) is a promising candidate for the treatment of ischemic stroke. However, accumulating evidence demonstrated that VEGF could exacerbate blood–brain barrier (BBB) disruption after ischemic stroke. This study was designed to investigate the underlying mechanisms. In the present study, a transient (90 min) middle cerebral artery occlusion (MCAO) model was performed to induce ischemic stroke in mice. VEGF was administered intracerebroventricularly 3 h after reperfusion. A gene expression microarray was utilized to investigate the differentially expressed genes among the sham, MCAO, and VEGF groups. A total of 3381 mRNAs were significantly altered by cerebral ischemia when compared with the sham group, and 15 of them were changed in the VEGF group when compared with the MCAO group. Among the 15 genes, orosomucoid (Orm) 1 was most sharply changed, and this gene has previously been reported to maintain the permeability of microvessels and integrity of the BBB. Results of the microarray showed that the expression of Orm1 increased after cerebral ischemia, whereas it decreased in response to VEGF, which was confirmed by real-time quantitative PCR, western blotting, immunohistochemistry, and immunofluorescence. The bioinformatics analysis indicated two NF-κB binding sites on the Orm1 promoter, and a super-shift assay verified that NF-κB could bind the Orm1 promoter. Results of the electrophoretic mobility shift assay (EMSA) revealed that VEGF inhibited the DNA-binding activity of NF-κB/p65. Furthermore, the elevated expression and activation of key members in the canonical NF-κB pathway induced by cerebral ischemia were also inhibited by VEGF treatment. In conclusion, this study demonstrated that decreasing the Orm1 expression via inhibition of the NF-κB pathway could be a possible mechanism involved in the aggravation of BBB disruption after stroke by VEGF. [ABSTRACT FROM AUTHOR]

Highlights: [•] Body temperature decreased spontaneously after MCAO in mouse. [•] Postischemic warming process increased success rate of mouse MCAO model. [•] Postichemic warming increased infarct volume and neurological deficits. [•] We achieved higher success rate by using a simple incubator. [ABSTRACT FROM AUTHOR]

Nerve growth factor (NGF) has been proved with the potential of promoting neurogenesis in adult mammalians. This study was aimed to investigate the effect of intranasal (IN) NGF on striatal neurogenesis and functional recovery in adult rats with focal cerebral ischemia. Rats were subjected to middle cerebral artery occlusion (MCAO) for 2 h, and then reperfused. NGF or vehicle was intranasally administered 24 h after cerebral reperfusion, and the treatments continued for 6 consecutive days there after. All animals were injected with 5-bromodeoxyuridine (BrdU) twice daily for 5--7 days after MCAO, and sacrificed 1 day and 28 days, respectively, after the last BrdU injection. Neural cell proliferation and survival in different brain regions were analyzed. Functional tests and immunohistochemical staining were also performed. The results showed that treatment with IN NGF failed to increase cell proliferation but improved survival of newly generated cells in ipsilateral striatum and subventricular zones (SVZ). Double immunofluorescence with BrdU and neuronal nuclei protein, a mature neuronal marker, were increased in striatum and SVZ in rats treated with IN NGF. The functional recovery was also observed at time of neurogenesis enhancement in striate. In conclusion, IN NGF may enhance neurogenesis and survival of newly generated cells, which may result in improved functional recovery after cerebral ischemia. [ABSTRACT FROM AUTHOR]

Bone marrow mesenchymal stem cell (BMSC) transplantation is a promising treatment for ischemic stroke that carries a severe mortality and disability burden amongst the adult population globally. Thus far, BMSC transplantation has been insufficient for ameliorating neurological deficits resulting from cerebral ischemia. This shortcoming may be an outcome due to poor homing and viability of grafted cells in ischemic brain that limit the potential therapeutic benefits of BMSC transplantation. Insulin-like growth factor-1 (IGF-1), a potent anti-apoptotic agent, exerts neuroprotective effects in ischemic stroke as well as rescuing neuronal death in vitro. We hypothesized that IGF-1 could also protect BMSCs from apoptotic death, and examined whether the combination of BMSCs with IGF-1 can enhance functional recovery outcomes in mice following cerebral ischemia. Intranasal administration of BMSCs with IGF-1 was applied in a mouse focal ischemic stroke model. Our in vitro results indicated that BMSCs treated with IGF-1 exhibited less apoptotic death induced by oxygen-glucose deprivation (OGD), and an improved migratory capacity. At 14 days after ischemic insult, the combination of BMSCs with IGF-1 resulted in a larger number of NeuN/BrdU and Glut-1/BrdU co-labeled cells in the areas contiguous to the ischemic core than IGF-1 or BMSC treatment alone. Western blot assays demonstrated that the protein levels of BDNF, VEGF and Ang-1 were significantly upregulated in the peri-infarct region in the combination treatment group compared with single IGF- 1 or BMSC treatment. Co-administration of BMSCs and IGF-1 markedly increases local cerebral blood flow and promoted better functional behavior outcomes. These data suggest that intranasal delivery of BMSCs in conjunction with IGF-1 strengthened functional recovery following ischemia via increasing neurogenesis and angiogenesis, providing a novel optimized strategy for improving the therapeutic efficacy of BMSC transplantation for ischemia. • Intranasally delivered bone marrow mesenchymal stem cells (BMSCs) after ischemic stroke • Co-applied insulin-like growth factor-1 (IGF-1) protected BMSCs from apoptosis and promoted cell migration • Combination of BMSCs with IGF-1 enhanced functional outcomes after stroke. • Upregulated BDNF, VEGF and Ang-1 in the peri-infarct region may mediate the beneficial effects. • Intranasal BMSCs and IGF-1 strengthened functional recovery after ischemia via increasing neurogenesis and angiogenesis. [ABSTRACT FROM AUTHOR]

Background: Functions of astrocytes in the rehabilitation after ischemic stroke, especially their impacts on inflammatory processes, remain controversial. This study uncovered two phenotypes of astrocytes, of which one was helpful, and the other harmful to anoxic neurons after brain ischemia.Methods: We tested the levels of inflammatory factors including TNF-a, IL-6, IL-10, iNOS, IL-1beta, and CXCL10 in primary astrocytes at 0 h, 6 h, 12 h, 24 h, and 48 h after OGD, grouped the hypoxia astrocytes into iNOS-positive (iNOS(+)) and iNOS-negative (iNOS(-)) by magnetic bead sorting, and then co-cultured the two groups of cells with OGD-treated neurons for 24 h. We further verified the polarization of astrocytes in vivo by detecting the co-localization of iNOS, GFAP, and Iba-1 on MCAO brain sections. Lentivirus overexpressing LCN2 and LCN2 knockout mice (#024630. JAX, USA) were used to explore the role of LCN2 in the functional polarization of astrocytes. 7.0-T MRI scanning and the modified Neurological Severity Score (mNSS) were used to evaluate the neurological outcomes of the mice.Results: After oxygen-glucose deprivation (OGD), iNOS mRNA expression increased to the peak at 6 h in primary astrocytes, but keep baseline expression in LCN2-knockout astrocytes. In mice with transient middle cerebral artery occlusion (tMCAO), LCN2 was proved necessary for astrocyte classical activation. In LCN2 knockout mice with MCAO, no classically activated astrocytes were detected, and smaller infarct volumes and better neurological functions were observed.Conclusions: The results indicated a novel pattern of astrocyte activation after ischemic stroke and lipocalin-2 (LCN2) plays a key role in polarizing and activating astrocytes. [ABSTRACT FROM AUTHOR]