📋 Browse Articles

In the core of a stroke, cell death occurs within minutes. In the penumbra, activity quickly drops, but cells typically remain viable for several hours. Improving neuronal survival in the penumbra is crucial for enhancing recovery in patients with stroke. Earlier work showed that mild activation may improve recovery, but the mechanisms are unclear. Brain-derived neurotrophic factor (BDNF) is well recognized for its neuroprotective functions via activation of tyrosine receptor kinase B (TrkB) receptors, and its release is activity-dependent. This study explored the role of BDNF/TrkB signaling in neuronal survival under hypoxic conditions, using cultures of dissociated cortical rat neurons. When exposed to hypoxia, activity quickly drops and cells become apoptotic after ∼12 h, similar to observations in the ischemic penumbra. Inhibition of the TrkB receptor in healthy, normoxic cultures led to a fivefold increase in apoptosis, confirming the importance of BDNF/TrkB signaling for cell viability in these preparations. The addition of BDNF to hypoxic cultures significantly improved neuronal survival, comparable with the effects of mild activation. These findings suggest that the beneficial effect of mild stimulation to prevent apoptosis in hypoxic cultures is mediated by BDNF/TrkB signaling, offering insights for potential therapeutic strategies aimed at promoting neuronal recovery after a stroke. Show less

Huangqi Guizhi Wuwu Decoction (HGWD) is a classic formula recorded in the Jin Gui Yao Lue. It is primarily used to treat symptoms of "blood stasis", such as numbness in the limbs and poor circulation, and has been widely applied clinically in the treatment of stroke. Its traditional efficacy suggests potential for promoting neurological function recovery and regulating the microenvironment. However, its mechanism in neuroprotection and functional recovery after ischemic stroke (IS) remains unclear. This study aims to elucidate the molecular mechanism by which HGWD exerts neuroprotective effects and promotes neurological recovery following IS by inducing M2 polarization of microglia through activation of the PI3K/Akt/mTOR signaling pathway. The chemical constituents of HGWD were identified using Ultra Performance Liquid Chromatography-Mass Spectrometry (UHPLC-MS). Network pharmacology was employed to predict the active components of HGWD and targets, along with potential signaling pathways. A middle cerebral artery occlusion (MCAO) in vivo model was established using Sprague-Dawley (SD) rats, whilst primary microglia were isolated to construct an oxygen-glucose deprivation/reoxygenation (OGD/R) in vitro model. TTC staining was used to assess the volume of cerebral infarction, and neurological function was evaluated using mNSS and the rotarod test. RT-qPCR, Western blot, immunofluorescence, or flow cytometry were used to detect axonal remodeling, the PI3K/Akt/mTOR signaling pathway, and microglial polarization markers, while ELISA was used to detect inflammatory cytokines. The in vivo dosage of HGWD was 2.5 g/kg i.g. and 5 g/kg i.g., and the in vitro concentrations were 50 μg/mL and 100 μg/mL. Using LY294002 and Rapamycin as PI3K and mTOR inhibitors, we verified that HGWD promotes the recovery of neurological function after IS by activating the PI3K/Akt/mTOR signaling pathway. Network pharmacology revealed that the core components of HGWD overlap with the PI3K/Akt/mTOR signaling pathway and microglial polarization targets. HGWD significantly improved neurological function in MCAO rats, reduced cerebral infarction area, and increased neuronal survival. This formula increased the expression of GAP-43, PSD95, and BDNF, while promoting axonal remodeling and synaptic repair. HGWD inhibited the expression of M1-type markers (CD86, iNOS) and increased the expression of M2-type markers (CD206, ARG1), while ELISA showed a shift of inflammatory cytokines towards anti-inflammatory effects. In microglia, HGWD restored OGD/R-induced cell viability and promoted M2 polarization via the PI3K/Akt/mTOR signaling pathway. Both in vivo and in vitro experiments showed that HGWD significantly increased the phosphorylation levels of PI3K, Akt, and mTOR. LY294002 and rapamycin partially blocked these results, while rescue experiments using the Akt activator SC79 combined with analysis of downstream STAT3 and P65 further illustrate that this process is Akt pathway dependent. The results suggest that HGWD can exert a neuroprotective effect by activating the PI3K/Akt/mTOR signaling pathway, thereby promoting neurological function recovery. HGWD may activate the PI3K/Akt/mTOR signaling pathway, drive microglia to M2 polarization, regulate neuroinflammation, and promote neuroplasticity, thereby achieving neuroprotection and functional recovery after IS. Show less

Stroke induces severe neurological impairment, however, there is limited understanding of the mechanisms underlying post-stroke recovery. Nuclear factor erythroid 2-related factor 2 (NRF2) and brain-derived neurotrophic factor (BDNF) have been implicated in tissue responses to ischemic injury; however, their temporal interactions in middle cerebral artery occlusion (MCAO) models are not fully understood. Male C57BL/6 mice (7-8 weeks) were subjected to transient MCAO (tMCAO). Motor behavior, cerebral blood flow, and temporal changes in NRF2, heme oxygenase-1 (HO-1), and BDNF expression were assessed over 14 days. Cerebral blood flow in the ischemic cortex remained significantly reduced for up to 14 days after MCAO. Motor deficits were most severe on day 3 and showed gradual recovery by day 7. NRF2 expression peaked on day 3, whereas HO-1 and BDNF expression increased on days 7 and 14, coinciding with improved motor performance and increased neuronal preservation. These findings indicate that activation of the NRF2/HO-1 pathway is temporally associated with increased expression of endogenous BDNF and recovery of motor function following ischemic injury in male mice. Show less

To evaluate the preventive effect of dipeptidyl peptidase-4 inhibitors (DPP-4i) on post-stroke cognitive impairment (PSCI) in patients with type 2 diabetes mellitus (T2DM) and concurrent acute ischemic stroke (AIS). A retrospective cohort study was conducted on 236 patients with T2DM+AIS recruited from April 2021 to October 2024. Patients were grouped based on DPP-4i use: an observation group (107 cases) with DPP-4i therapy and a control group (129 cases) without. Patients' baseline demographics, clinical features, laboratory indices, and follow-up data were extracted from the electronic medical record system. The primary outcome measure was the incidence of PSCI, defined as a Montreal Cognitive Assessment Scale (MoCA) score <26 at six months after AIS. Secondary outcomes included inflammatory cytokines, oxidative stress markers, neuroprotective factors (BDNF), glycemic metabolism indicators, and life quality [Barthel Index (BI), Functional Independence Measure (FIM), and Instrumental Activities of Daily Living (IADL)]. At 6 months after AIS, the incidence of PSCI was significantly lower in the observation group than in the control group (P<0.05). Furthermore, inflammatory and oxidative stress marker levels were decreased whereas BDNF level was significantly elevated in the observation group compared to the control group (all P<0.05). According to the quality-of-life assessment, patients receiving DPP-4i had higher BI, FIM, and IADL scores (P<0.05), along with a lower all-cause readmission rate (P<0.05). Subgroup analysis indicated that different DPP-4i types (e.g., sitagliptin, saxagliptin) had consistent cognitive protective effects (P>0.05). DPP-4i can lower PSCI risk in T2DM+AIS patients. Its mechanism involves multi-dimensional effects like anti-inflammation, anti-oxidation, insulin sensitivity enhancement, and neuroprotection. Show less

Memantine (Mem), an uncompetitive antagonist of the N-methyl-D-aspartate receptor (NMDAr), has demonstrated neuroprotective effects in preclinical stroke models by reducing excitotoxic damage. However, the efficacy of low acute doses administered during the immediate post-ischemic phase remains insufficiently characterized. Male rats underwent permanent middle cerebral artery occlusion (pMCAO) and received a single intraperitoneal dose of Mem (5 mg/kg) two hours post-occlusion. Neurological deficits were assessed using the modified Neurological Severity Score (mNSS). Infarct area and neuronal preservation were quantified using MAP2 immunohistochemistry. BDNF and PSD95 protein levels were measured by ELISA, and their gene expression was evaluated via RT-PCR. Mem treatment significantly reduced infarct area (p = 0.000029) and attenuated neurological deficits (p < 0.0001). MAP2 immunoreactivity was higher in the Mem-treated group (p = 0.000003), indicating preservation of neuronal structure. BDNF protein levels did not differ between the pMCAO and pMCAO+Mem groups; PSD95 protein and its corresponding DLG4 mRNA were increased in the pMCAO group compared with Sham. In the other groups, levels remained unchanged. Early administration of low-dose memantine confers acute neuroprotection after stroke by reducing tissue damage and preserving neuronal integrity, without affecting ischemia-induced BDNF and PSD95 protein and gene expression. These findings suggest a selective early neuroprotective mechanism and highlight the need for long-term and sex-inclusive studies to further evaluate memantine's therapeutic potential. Show less

Post-stroke neurogenic bladder dysfunction impairs patients' quality of life, yet current treatments offer limited effectiveness. This study investigated the therapeutic effects and underlying mechanisms of human amniotic fluid stem cell-derived extracellular vesicle (hAFSC-EV) on bladder dysfunction and neurovascular plasticity after cerebral ischemia. Thirty-six female rats underwent bilateral ovariectomy and were assigned to sham-operated or 90-min middle cerebral artery occlusion (MCAO) groups, with or without a single injection of hAFSC-EVs. Magnetic resonance imaging (MRI), cystometry, blood-brain barrier (BBB) permeability, and markers of neurogenesis and angiogenesis in ischemic brain were assessed. Bladder levels of brain-derived neurotrophic factor (BDNF), β3-adrenoceptor, adenylate cyclase, and M2- and M3-muscarinic receptors were evaluated at 7 and 28 days post-MCAO or sham-operation. Compared with untreated rats, hAFSC-EV treatment significantly reduced cerebral infarct volume and BBB leakage, and enhanced microvessel and vascular density, along with angiogenesis. Neural markers such as BDNF, nestin, and doublecortin were significantly upregulated at 7 and/or 28 days post-MCAO. hAFSC-EV treatment ameliorated MCAO-induced bladder dysfunction by reducing peak voided volume, intercontraction interval, and bladder capacity, along with improving residual urine volume. hAFSC-EV treatment significantly increased bladder expression of BDNF and M3-muscarinic receptors, and recovers the expressions of M2, β3-adrenoceptor, and adenylate cyclase to near control levels at 7 and 28 days post-MCAO. hAFSC-EV treatment improves neurogenic bladder dysfunction and cerebral ischemia post-MCAO, potentially through reducing infarct volume and BBB disruption, enhancing neurogenesis and angiogenesis in the ischemic brain, and modulating the expression of bladder BDNF, β3-adrenoceptor, adenylate cyclase and muscarinic receptors. Show less

With the global population growing and aging, along with increasing environmental, metabolic, and lifestyle-related risk factors, the worldwide incidence of stroke, Alzheimer's disease (AD) and other dementias, meningitis, and other neurological disorders-along with associated mortality-has risen significantly. Proanthocyanidins (PCs), which are oligomers and polymers of flavan-3-ols, are widely distributed across the plant kingdom, including in grape seeds, cinnamon, apples, cranberries, lotus seeds, and pine bark. They represent the second most abundant class of polyphenols in nature, after lignin. A substantial body of preclinical evidence indicates that PCs exert significant neuroprotective effects through multiple mechanisms. This review provides a systematic overview of the sources, structural characteristics, and bioavailability of PCs, with a focus on their pharmacological mechanisms in nervous system disease. Specifically, it examines their roles in regulating oxidative stress, neuroinflammation, protein homeostasis, apoptosis, autophagy, and key signaling pathways, including Nrf2/HO-1, CREB/BDNF, PI3K/Akt, MAPK, and NF-κB. Furthermore, this review systematically summarized the distinct structural forms of PCs, including monomers, dimers, trimers, and polymers, and explores their structure-activity relationships (SARs) in modulating the gut-brain axis. Additionally, recent advances in PCS-based nano-delivery systems and clinical studies related to neurological disorders are summarized. Growing evidence indicates that microbial metabolism in the gut serves as a key mechanism underlying their neuroprotective effects. Finally, the potential applications of PCs as promising dietary supplements or therapeutic agents for the prevention and treatment of nervous system diseases are discussed, along with existing challenges and future perspectives. Show less

Post-stroke depression (PSD) is a common and clinically significant stroke complication associated with impaired rehabilitation potential and increased mortality risk. The prevalence of PSD varies from 25% to 59% depending on the duration of observation, reaching a peak in the first years after a stroke. The pathogenesis of PSD results from a complex interplay of biological and psychological factors that extends well beyond monoamine deficiency. Damage to monoaminergic pathways, neuroinflammation, hypothalamic-pituitary-adrenal axis dysfunction, decreased neuroplasticity (including BDNF deficiency), and impaired neural network integrity play a key role. The clinical presentation includes a complex of affective (apathy, anhedonia), cognitive (impaired executive functions), and dyssomnia disorders. While selective serotonin reuptake inhibitors remain the first choice for treatment of PSD, the current therapeutic approach requires targeting all pathogenesis links. A promising direction is the use of antidepressants with a complex mechanism of action, such as the original fluvoxamine, which combines serotonergic effects with anti-inflammatory and neuroprotective properties through sigma-1 receptor agonism. Optimizing PSD treatment is possible through a personalized approach that includes thorough screening and comprehensive correction of identified disorders. Show less

Post-stroke depression (PSD) is a common and clinically significant complication of stroke, associated with worse rehabilitation potential and increased mortality risk. The prevalence of PSD varies from 25% to 59%, depending on the duration of follow-up, peaking in the first years after the stroke event. The pathogenesis of PSD results from a complex interplay of biological and psychological factors, extending far beyond monoamine deficiency. Key roles are played by damage to monoaminergic pathways, neuroinflammation, dysfunction of the hypothalamic-pituitary-adrenal axis, reduced neuroplasticity (including BDNF deficit), and impaired integrity of neuronal networks. The clinical picture is characterized by a complex of affective (apathy, anhedonia), cognitive (executive dysfunction), and dyssomnic disorders. Although selective serotonin reuptake inhibitors remain the first-line treatment, the modern therapeutic approach to PSD requires targeting all components of its pathogenesis. A promising direction is the use of antidepressants with a multimodal mechanism of action, such as the original drug fluvoxamine, which combines serotonergic effects with anti-inflammatory and neuroprotective properties via sigma-1 (σ1) receptor agonism. Optimizing PSD treatment is achievable through the implementation of a personalized approach, including long-term screening and comprehensive management of the identified disorders. Show less