Signaling pathways are critical modulators of a variety of physiological and pathological processes, and the abnormal activation of some signaling pathways can contribute to disease progression in ...various conditions. As a result, signaling pathways have emerged as an important tool through which the occurrence and development of diseases can be studied, which may then lead to the development of novel drugs. Accumulating evidence supports a key role for extracellular signal-regulated kinase 1/2 (ERK1/2) signaling in the embryonic development of the central nervous system (CNS) and in the regulation of adult brain function. ERK1/2, one of the most well characterized members of the mitogen-activated protein kinase family, regulates a range of processes, from metabolism, motility and inflammation, to cell death and survival. In the nervous system, ERK1/2 regulates synaptic plasticity, brain development and repair as well as memory formation. ERK1/2 is also a potent effector of neuronal death and neuroinflammation in many CNS diseases. This review summarizes recent findings in neurobiological ERK1/2 research, with a special emphasis on findings that clarify our understanding of the processes that regulate the plethora of isoform-specific ERK functions under physiological and pathological conditions. Finally, we suggest some potential therapeutic strategies associated with agents acting on the ERK1/2 signaling to prevent or treat neurological diseases.
Protein kinases are critical modulators of a variety of intracellular and extracellular signal transduction pathways, and abnormal phosphorylation events can contribute to disease progression in a ...variety of diseases. As a result, protein kinases have emerged as important new drug targets for small molecule therapeutics. The mitogen-activated protein kinase (MAPK) signaling pathway transmits signals from the cell membrane to the nucleus in response to a variety of different stimuli. Because this pathway controls a broad spectrum of cellular processes, including growth, inflammation, and stress responses, it is accepted as a therapeutic target for cancer and peripheral inflammatory disorders. There is also increasing evidence that MAPK is an important regulator of ischemic and hemorrhagic cerebral vascular disease, raising the possibility that it might be a drug discovery target for stroke. In this review, we discuss the MAPK signaling pathway in association with its activation in stroke-induced brain injury.
The role of endovascular therapy for acute stroke with a large infarction has not been extensively studied in differing populations.
We conducted a multicenter, prospective, open-label, randomized ...trial in China involving patients with acute large-vessel occlusion in the anterior circulation and an Alberta Stroke Program Early Computed Tomography Score of 3 to 5 (range, 0 to 10, with lower values indicating larger infarction) or an infarct-core volume of 70 to 100 ml. Patients were randomly assigned in a 1:1 ratio within 24 hours from the time they were last known to be well to undergo endovascular therapy and receive medical management or to receive medical management alone. The primary outcome was the score on the modified Rankin scale at 90 days (scores range from 0 to 6, with higher scores indicating greater disability), and the primary objective was to determine whether a shift in the distribution of the scores on the modified Rankin scale at 90 days had occurred between the two groups. Secondary outcomes included scores of 0 to 2 and 0 to 3 on the modified Rankin scale. The primary safety outcome was symptomatic intracranial hemorrhage within 48 hours after randomization.
A total of 456 patients were enrolled; 231 were assigned to the endovascular-therapy group and 225 to the medical-management group. Approximately 28% of the patients in both groups received intravenous thrombolysis. The trial was stopped early owing to the efficacy of endovascular therapy after the second interim analysis. At 90 days, a shift in the distribution of scores on the modified Rankin scale toward better outcomes was observed in favor of endovascular therapy over medical management alone (generalized odds ratio, 1.37; 95% confidence interval, 1.11 to 1.69; P = 0.004). Symptomatic intracranial hemorrhage occurred in 14 of 230 patients (6.1%) in the endovascular-therapy group and in 6 of 225 patients (2.7%) in the medical-management group; any intracranial hemorrhage occurred in 113 (49.1%) and 39 (17.3%), respectively. Results for the secondary outcomes generally supported those of the primary analysis.
In a trial conducted in China, patients with large cerebral infarctions had better outcomes with endovascular therapy administered within 24 hours than with medical management alone but had more intracranial hemorrhages. (Funded by Covidien Healthcare International Trading Shanghai and others; ANGEL-ASPECT ClinicalTrials.gov number, NCT04551664.).
Atherosclerosis is closely associated with ischemic stroke, and long noncoding RNA-H19 (lncRNA-H19) might be a potential target for treating atherosclerosis. The present study aimed to investigate ...the function of lncRNA-H19 in atherosclerosis and to explore a novel therapeutic strategy for ischemic stroke.
Differentially expressed genes (DEGs) in atherosclerosis were screened by searching public database. In combination with the lncRNA-H19-knockout database, potential lncRNA-H19-mediated gene was retrieved and their relationship was identified. In order to assess the detailed regulatory mechanism of lncRNA-H19, we used a lentivirus packaging system to upregulate Acp5 (Acid phosphatase 5) expression in vascular smooth muscle cells (VSMC) and human umbilical vein endothelial cells (HUVECs). The expression of ACP5 was determined by Western Blot, and evaluations of cell proliferation and apoptosis were detected. An ischemic stroke mouse model was established. Atherosclerosis was measured by using plaque area size. The effects H19 on the expression of ACP5 were explored by the overexpression or silence of H19.
H19 and ACP5 were associated with Acute Stroke Treatment (TOAST) subtypes of atherosclerotic patients. The target prediction program and dual-luciferase reporter confirmed ACP5 as a direct target of H19. Lentivirus-mediated H19-forced expression upregulated ACP5 protein levels, promoted cell proliferation and suppressed the apoptosis. The plaque area size was larger in ischemic models than controls. The overexpression or silence of H19 increased or reduced the plaque size. The overexpression or silence of H19 resulted in the expression or inhibition of ACP5.
IncRNA-H19 promoting ACP5 protein expression contributed to atherosclerosis and increased the risk of ischemic stroke.
Spinocerebellar ataxia type 1 (SCA1) is an autosomal dominant neurodegenerative disorder caused by CAG repeat mutations in the ATXN1 gene. In this study, we generated an induced pluripotent stem cell ...line (iPSC) by using non-integrating Sendai virus (SeV) from peripheral blood mononuclear cells(PBMCs)of SCA1 patient harboring a CAG repeat mutation in the ATXN1 gene. The induced patient-specific iPSC line with a normal karyotype and expresses pluripotent markers, it also shows differentiation totipotency and tridermogenesis in vitro. It may be an excellent model for studying spinocerebellar ataxia type 1 (SCA1) in vitro and will be beneficial for studying SCA1 pathogenesis and therapeutic intervention strategies.
Ischemic stroke is a major cerebrovascular disease resulting from a transient or permanent local reduction of cerebral blood flow. Angiogenesis plays an important role in cerebral microvascular ...repair after ischemic stroke. This study aimed at investigating the effect of NF-E2-related factor 2 (Nrf2) on the angiogenesis of mouse cerebral microvascular endothelial bEnd.3 cells in a hypoxic environment. We found that Nrf2 expression was temporarily increased in hypoxia-induced bEnd.3 cells. Knockdown of Nrf2 inhibited the proliferation, migration, as well as tube formation in hypoxia-induced bEnd.3 cells. Meanwhile, vascular endothelial growth factor and PI3K/Akt signaling pathways were identified to be regulated by Nrf2 in hypoxia-induced bEnd.3 cells. It was found that silencing of Nrf2 downregulated the expression levels of NAD(P)H:quinine oxidoreductase-1, vascular endothelial growth factor, p-Akt, and heme oxygenase-1 in hypoxia-induced bEnd.3 cells. Data suggested that hypoxia induced the transient increase of Nrf2, which plays a key role in the angiogenesis of cerebral microangiogenesis, and that Nrf2 regulates the proliferation, migration, as well as tube formation likely through PI3K/Akt signaling pathway in hypoxia-induced bEnd.3 cells. Our study provides proof of concept for the modulation of Nrf2, so as to tilt the balance toward angiogenesis, representing a therapeutic strategy for hypoxia or ischemia disorders such as stroke.
Evidence for the preventative effects of percutaneous transluminal angioplasty and stenting (PTAS) on the recurrence of stroke in patients with severe intracranial vertebrobasilar stenoses (IVBS) ...varies, and the influence of study characteristics on the study outcomes have not been determined.
A study level based meta-analysis was performed to investigate the influence of baseline characteristics on the 30-day and follow-up stroke recurrence or death in symptomatic IVBS patients receiving PTAS. Relevant single center studies were retrieved by searching PubMed and Embase. A random effect model was applied to synthesize the outcomes. Meta-regression and subgroup analyses were performed to evaluate the potential influence of study characteristics on outcomes.
Fifteen cohort studies comprising 554 symptomatic IVBS patients were included. PTAS was associated with an 8% incidence of stroke recurrence or death (95% CI: 5% to 12%) in IVBS patients within 30 days, and 8 per 100 person-years (95% CI: 5 to 11 per 100 person-years) of cumulative stroke recurrence or death during follow-up. Meta-regression indicated that the center volume, as defined by the numbers of cases per year, was negatively correlated with 30-day (regression coefficient = -0.09, p = 0.02) and follow-up (regression coefficient = -0.60, p = 0.01) stroke recurrence or death. Age, gender, or comorbidities have no significant effect on the outcomes.
Centers of higher procedural volume may be associated with better clinical outcomes for symptomatic IVBS patients receiving PTAS.
The optimum systolic blood pressure after endovascular thrombectomy for acute ischaemic stroke is uncertain. We aimed to compare the safety and efficacy of blood pressure lowering treatment according ...to more intensive versus less intensive treatment targets in patients with elevated blood pressure after reperfusion with endovascular treatment.
We conducted an open-label, blinded-endpoint, randomised controlled trial at 44 tertiary-level hospitals in China. Eligible patients (aged ≥18 years) had persistently elevated systolic blood pressure (≥140 mm Hg for >10 min) following successful reperfusion with endovascular thrombectomy for acute ischaemic stroke from any intracranial large-vessel occlusion. Patients were randomly assigned (1:1, by a central, web-based program with a minimisation algorithm) to more intensive treatment (systolic blood pressure target <120 mm Hg) or less intensive treatment (target 140–180 mm Hg) to be achieved within 1 h and sustained for 72 h. The primary efficacy outcome was functional recovery, assessed according to the distribution in scores on the modified Rankin scale (range 0 no symptoms to 6 death) at 90 days. Analyses were done according to the modified intention-to-treat principle. Efficacy analyses were performed with proportional odds logistic regression with adjustment for treatment allocation as a fixed effect, site as a random effect, and baseline prognostic factors, and included all randomly assigned patients who provided consent and had available data for the primary outcome. The safety analysis included all randomly assigned patients. The treatment effects were expressed as odds ratios (ORs). This trial is registered at ClinicalTrials.gov, NCT04140110, and the Chinese Clinical Trial Registry, 1900027785; recruitment has stopped at all participating centres.
Between July 20, 2020, and March 7, 2022, 821 patients were randomly assigned. The trial was stopped after review of the outcome data on June 22, 2022, due to persistent efficacy and safety concerns. 407 participants were assigned to the more intensive treatment group and 409 to the less intensive treatment group, of whom 404 patients in the more intensive treatment group and 406 patients in the less intensive treatment group had primary outcome data available. The likelihood of poor functional outcome was greater in the more intensive treatment group than the less intensive treatment group (common OR 1·37 95% CI 1·07–1·76). Compared with the less intensive treatment group, the more intensive treatment group had more early neurological deterioration (common OR 1·53 95% 1·18–1·97) and major disability at 90 days (OR 2·07 95% CI 1·47–2·93) but there were no significant differences in symptomatic intracerebral haemorrhage. There were no significant differences in serious adverse events or mortality between groups.
Intensive control of systolic blood pressure to lower than 120 mm Hg should be avoided to prevent compromising the functional recovery of patients who have received endovascular thrombectomy for acute ischaemic stroke due to intracranial large-vessel occlusion.
The Shanghai Hospital Development Center; National Health and Medical Research Council of Australia; Medical Research Futures Fund of Australia; China Stroke Prevention; Shanghai Changhai Hospital, Science and Technology Commission of Shanghai Municipality; Takeda China; Hasten Biopharmaceutic; Genesis Medtech; Penumbra.
Ischemic stroke (IS) is the leading cause of disability and death worldwide. Owing to the aging population and unhealthy lifestyles, the incidence of cerebrovascular disease is high. Vascular risk ...factors include hypertension, diabetes, dyslipidemia, and obesity. Therefore, in addition to timely and effective reperfusion therapy for IS, it is crucial to actively control these risk factors to reduce the incidence and recurrence rates of IS. Evidence from human and animal studies suggests that moderate intermittent hypoxia (IH) exposure is a promising therapeutic strategy to ameliorate common vascular risk factors and comorbidities. Given the complex pathophysiological mechanisms underlying IS, effective treatment must focus on reducing injury in the acute phase and promoting repair in the recovery phase. Therefore, this review discusses the preclinical perspectives on IH conditioning as a potential treatment for neurovascular injury and highlights IH pre and postconditioning strategies for IS. Hypoxia conditioning reduces brain injury by increasing resistance to acute ischemic and hypoxic stress, exerting neuroprotective effects, and promoting post-injury repair and regeneration. However, whether IH produces beneficial effects depends not only on the hypoxic regimen but also on inter-subject differences. Therefore, we discuss the factors that may influence the effectiveness of IH treatment, including age, sex, comorbidities, and circadian rhythm, which can be used to help identify the optimal intervention population and treatment protocols for more accurate, individualized clinical translation. In conclusion, IH conditioning as a non-invasive, non-pharmacological, systemic, and multi-targeted intervention can not only reduce brain damage after stroke but can also be applied to the prevention and functional recovery of IS, providing brain protection at different stages of the disease. It represents a promising therapeutic strategy. For patients with IS and high-risk groups, IH conditioning is expected to develop as an adjunctive clinical treatment option to reduce the incidence, recurrence, disability, and mortality of IS and to reduce disease burden.
Ischemic stroke is associated with increasing morbidity and has become the main cause of death and disability worldwide. Cerebral edema is a serious complication arising from ischemic stroke. It ...causes an increase in intracranial pressure, rapid deterioration of neurological symptoms, and formation of cerebral hernia, and is an important risk factor for adverse outcomes after stroke. To date, the detailed mechanism of cerebral edema after stroke remains unclear. This limits advances in prevention and treatment strategies as well as drug development. This review discusses the classification and pathological characteristics of cerebral edema, the possible relationship of the development of cerebral edema after ischemic stroke with aquaporin 4, the SUR1-TRPM4 channel, matrix metalloproteinase 9, microRNA, cerebral venous reflux, inflammatory reactions, and cerebral ischemia/reperfusion injury. It also summarizes research on new therapeutic drugs for post-stroke cerebral edema. Thus, this review provides a reference for further studies and for clinical treatment of cerebral edema after ischemic stroke.
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