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Cholinergic dysfunction is a key contributor to cognitive impairment observed in aging and neurodegenerative disorders such as Alzheimer's disease (AD). Although acetylcholinesterase (AChE) inhibitors have been the mainstay of symptomatic treatment for over two decades, their limited efficacy and adverse effects underscore the need for alternative therapeutic approaches. Recent evidence indicates that mechanical stimulation can modulate neuronal and glial signaling through mechanotransduction, suggesting a potential strategy to enhance cognitive function via non-pharmacological means. Here, we developed a head-mounted vibrotactile stimulation system (HVSS) that delivers controlled vibration to the cranium and evaluated its effects in a pharmacological model of acute cholinergic dysfunction induced by scopolamine. To this end, male C57BL/6 mice received scopolamine (1 mg/kg, i.p.; on days 7, 14, and 28) and were exposed to daily vibrotactile stimulation at 20, 40, or 80 Hz for 28 days. Behavioral performance was assessed using passive avoidance and Morris water maze tests, followed by biochemical and histological analyses. HVSS at 40 Hz and 80 Hz significantly improved cognitive performance, enhanced hippocampal cholinergic function, reduced oxidative damage, and upregulated memory-related signaling genes, including BDNF, PI3K, AKt, ERK1/2, CREB, and CAMK4. These findings suggest that high-frequency HVSS improves memory hippocampal cholinergic function via activation of memory-related signaling pathways, highlighting its potential as a safe, non-pharmacological neuromodulatory strategy for cholinergic dysfunction-related cognitive decline. Show less

Dementia with Lewy Bodies (DLB) and Multiple System Atrophy (MSA) are neurodegenerative disorders with marked neuronal dysfunction and damage, accompanied by the accumulation of abnormal alpha-synuclein. Identifying the proteins involved in their specific neurodegenerative processes is important to understand shared or disease-specific mechanisms of neurodegeneration. Recent investigations into these disorders have revealed intriguing alterations in the functionality of neurotrophic factors, including and predominantly the Brain-Derived Neurotrophic Factor (BDNF). Thus, the aim of this study was to investigate the BDNF serum levels in two cohorts of DLB and MSA patients and compare them to those of healthy individuals. Investigating serum BDNF concentrations in these conditions may provide insights into aspects of the underlying mechanisms of neurodegeneration. Serum BDNF concentrations were determined using commercial enzyme-linked immunosorbent assays. All serum samples were tested in duplicate, and the reported BDNF concentrations were ng/ml. The findings demonstrated a significant increase in serum BDNF levels in both DLB and MSA patients versus healthy subjects. This increase may represent a compensatory neuroprotective response to ongoing neuronal damage or a reflection of disease-related pathophysiological mechanisms involving altered BDNF regulation. These findings contribute to a growing body of evidence implicating neurotrophic fac-tor dysregulation in the pathogenesis of α-synucleinopathies. Moreover, the findings highlight BDNF as a potential therapeutic target and a candidate adjunct biomarker for diagnosis, monitoring disease activity, or treatment response. Additional experiments will clarify this causal relationship and the utility of BDNF-based interventions in modifying the disease trajectories in DLB and MSA. Show less

Chronic stress is increasingly acknowledged as a pivotal precipitating factor in the pathogenesis of neuropsychiatric and neurodegenerative disorders, notably including depression and Alzheimer's disease (AD). Astrocytes, which constitute the predominant population of glial cells involved in the maintenance of synaptic homeostasis, the recycling of neurotransmitters, and the provision of metabolic support, display a pronounced susceptibility to sustained exposure to stress. The deleterious effects of astrocytic dysfunction instigate a series of neuroinflammatory and synaptic modifications that undermine both cognitive and emotional resilience. This review articulates the mechanistic interactions between stress-induced astrocyte dysfunction, neuroinflammatory signaling, and compromised neuroplasticity, underscoring the converging pathways that are implicated in both depression and AD. A thorough synthesis of the literature from 2020 to 2025 was conducted utilizing databases such as PubMed, Scopus, and Web of Science, with an emphasis on molecular, in vitro, in vivo, and translational studies that examine the modulation of astrocytic function under conditions of chronic stress and its pertinence to depression and AD. The chronic activation of the hypothalamic-pituitary-adrenal (HPA) axis precipitates morphological alterations, diminished expression of glutamate transporters (GLT-1/EAAT2), disrupted brain-derived neurotrophic factor (BDNF) signaling, and an augmented release of pro-inflammatory cytokines (IL-1β, IL-6, TNF-α) from astrocytes. These biochemical alterations exacerbate excitotoxicity, disturb monoaminergic and glutamatergic neurotransmission, and hasten synaptic degeneration. In the context of depression, this phenomenon is manifested as impaired mood regulation and a decline in neurogenesis. In AD, it synergistically interacts with amyloid-beta and tau pathologies to facilitate progressive cognitive impairment. Both conditions exhibit a common feature of diminished neurosignaling plasticity, which limits the brain's capacity for adaptation and repair. Astrocyte dysfunction constitutes a central mechanistic nexus wherein chronic stress, neuroinflammation, and synaptic pathology intersect to promote the progression of depression and AD. The targeting of astrocytic health via the modulation of reactive astrocyte phenotypes, the restoration of glutamate homeostasis, and the enhancement of neurotrophic signaling emerges as a promising therapeutic avenue for alleviating stress-related neurodegeneration and mood disorders. Show less

The prevalence of neurodegenerative disorders continues to increase with population aging. Brain-derived neurotrophic factor is a biomarker of cognitive function and neuroprotection. Lactobacillus plantarum C29-fermented soybean (DW2009) has been suggested to enhance cognition by modulating brain-derived neurotrophic factor. This secondary analysis of a randomized, double-blind, placebo-controlled trial investigated the influence of sociodemographic and lifestyle factors on serum brain-derived neurotrophic factor responsiveness to DW2009 supplementation. One hundred adults (age: 55-85 years) with mild cognitive impairment were randomized 1:1 to receive DW2009 (800 mg/day) or placebo (800 mg/day) for 12 weeks. The participants were examined, and their cognitive clinical features and serum brain-derived neurotrophic factor (BDNF) levels were measured at baseline and after a 12-week period. We found that DW2009 significantly increased serum BDNF levels, especially in older men (≥ 68 years) and in those with lower educational attainment (≤ 11 years). Subgroup analysis also indicated that the effect of DW2009 was enhanced in participants who performed frequent physical activity (≥ 5 times/week) and those within the normal body mass index range (18.5-22.9 kg/m²). Our findings suggest that the increase in serum BDNF after DW2009 supplementation is dependent on baseline characteristics, although this interpretation requires confirmation. DW2009 intake was linked to increased serum BDNF levels in individuals with specific sociodemographic and lifestyle characteristics. These findings suggest that personalized supplementation strategies may optimize functional benefits for cognitive health. Show less

Brain-derived neurotrophic factor (BDNF) plays a pivotal role in neuronal development, synaptic plasticity, and cognitive function, and its dysregulation is implicated in various neurodegenerative and neuropsychiatric disorders. To noninvasively monitor dynamic changes in Bdnf expression in vivo, we developed a novel transgenic mouse line, Bdnf-AkaLuc transgenic (Tg) mice, in which the coding region of BDNF was replaced in a BAC transgene with a mutant luciferase, AkaLuc. This luciferase is optimized for the synthetic substrate AkaLumine, which emits near-infrared bioluminescence suitable for deep-tissue imaging. This engineered bioluminescence imaging (BLI) system, termed AkaBLI, enables robust and highly sensitive detection of bioluminescence in the brains of living mice, significantly outperforming our previous Bdnf-Luciferase Tg model. Using this system, we successfully visualized activity-dependent Bdnf mRNA induction in response to pilocarpine-induced status epilepticus. To overcome the limitations of repeated imaging, we identified optimal BLI intervals and established a hairless Bdnf-AkaLuc Tg line, facilitating long-term longitudinal monitoring. Furthermore, by crossing Bdnf-AkaLuc Tg mice with 5xFAD Alzheimer's disease model mice, we successfully visualized reductions in Bdnf expression in the brains of living 5xFAD mice. Our study introduces a powerful tool for noninvasive, continuous visualization of Bdnf regulation under both physiological and disease-related conditions. This imaging approach holds potential for advancing our understanding of BDNF-related brain function and for evaluating therapeutic strategies targeting BDNF in neurological disorders. Show less

Huntington's Disease (HD) is a neurodegenerative ailment characterized by progressive motor, cognitive, and psychiatric decline, linked with mitochondrial dysfunction, oxidative stress, and neuroinflammation. Few effective treatments are available for Huntington's. Additionally, the therapeutic effects of natural polysaccharides against neurodegenerative disorders have not yet been fully explored. This study aimed to investigate the neuroprotective potential of Aloe Polysaccharides (APs) against 3-Nitropropionic Acid (3- NPA)-initiated HD-like symptoms in rats. Adult male rats were allocated to control, 3-NPA-treated, and APs-treated groups (100 and 200 mg/kg orally) following 3-NPA administration. Behavioral assessments (rotarod, open field, narrow beam walking) and biochemical analyses, including neurotransmitters [Acetylcholinesterase (AChE), Acetylcholine (ACh), Dopamine (DA), Norepinephrine (NE), Serotonin (5-HT), Gamma-Aminobutyric Acid (GABA), Glutamate (Glu)], oxidative/nitrative stress markers [Malondialdehyde (MDA, Nitric Oxide (NO)], antioxidant enzymes [Superoxide Dismutase (SOD), Catalase (CAT), Glutathione (GSH)], mitochondrial enzyme [Succinate Dehydrogenase (SDH)], inflammatory mediators [Nuclear Factor Kappa B (NF-κB), Tumor Necrosis Factor Alpha (TNF-α), Interleukin- 1 Beta (IL-1β), Cyclooxygenase-2 (COX-2)], neurotrophic factor [Brain-Derived Neurotrophic Factor (BDNF)], and apoptotic markers (caspase-3, caspase-9, B-Cell Lymphoma 2 (Bcl-2), Bcl-2-Associated X Protein (Bax)] were performed. Additionally, the impact of APs on regulators of mitochondrial biogenesis and antioxidant response [Nuclear Factor Erythroid 2-Related Factor 2 (Nrf2), Sirtuin 1 (Sirt1), Heme Oxygenase-1 (HO-1), NAD(P)H Quinone Dehydrogenase 1 (NQO1), Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-Alpha (PGC-1α), Adenosine Monophosphate-Activated Protein Kinase (AMPK), Uncoupling Protein 1 (UCP1), Uncoupling Protein 2 (UCP2)] was evaluated. Histopathological examination of the striatum was conducted. Statistical analysis was performed using one-way ANOVA followed by Tukey's post hoc test. 3-NPA administration induced significant motor deficits, neurotransmitter imbalance, elevated oxidative stress, inflammation, mitochondrial impairment, BDNF depletion, apoptosis, and striatal degeneration (P < 0.01). APs treatment significantly (P < 0.01; P < 0.001) reversed 3-NPA effects and improved behavioral performance (rotarod latency, OFT exploratory activity, and beam walk score); restored neurotransmitter balance; improved antioxidant enzymes (SOD, CAT, and GSH); mitigated MDA and NO effects; suppressed NF-κB, TNF-α, IL-1β, and COX-2; elevated BDNF and SDH activities; mitigated apoptosis (caspase-3 and 9, BAX, and BCl-2); and preserved striatal structure. APs showed neuroprotective potential in 3-NPA-induced HD rats by modulating the BDNF/NF-κB/Nrf2 pathway, controlling oxidative stress and neuroinflammation, restoring neurotransmitter function, and arresting striatal damage. Treatment with Aps markedly upregulated the levels of mitochondrial biogenesis-related proteins (Sirt1, PGC-1α, AMPK, UCP1, and UCP2) and antioxidant defense mediators (HO-1 and NQO1). In addition to behavioral and biochemical improvements, this study uniquely demonstrates that APs upregulate genes central to the mitochondrial biogenesis pathway, suggesting a new mechanistic basis for their neuroprotective effects in 3-NPA-induced HD. The study results showed that Applied Physiology Solution (APS) enhanced behavioural characteristics and neurotransmission function while simultaneously reducing the inflammatory response and cell stress and preserving striatal tissue structure. These findings reveal that APs promote neuroprotection not only by modulating oxidative stress, neuroinflammation, neurotransmission, and apoptosis, but also by specifically upregulating genes in the mitochondrial biogenesis pathway, highlighting their potential as a natural therapeutic candidate for HD management. Show less

Brain aging is a multifactorial process associated with oxidative stress, chronic neuroinflammation, and synaptic dysfunction, ultimately leading to cognitive decline and increased susceptibility to neurodegenerative disorders. Epigallocatechin gallate (EGCG) is a potent antioxidant and anti-inflammatory agent, but its therapeutic potential is limited by poor stability and bioavailability. In this study, a dual nano delivery system was developed by loading chitosan-EGCG nanoparticles into mesenchymal stem cell-derived exosomes (Ex-Chit-EGCG NPs) and evaluated for neuroprotective efficacy in a D-galactose-induced brain aging model. Intranasal administration of Ex-Chit-EGCG NPs significantly improved cognitive and locomotor performance compared with exosomes alone, as evidenced by enhanced outcomes in Y-maze and open field tests. Biochemical analyses revealed that Ex-Chit-EGCG NPs effectively reduced lipid peroxidation, restored glutathione levels, and reactivated the LKB1/AMPK/SIRT1 signaling pathway. Molecular investigations demonstrated upregulation of Nrf2, BDNF, and SIRT1 together with suppression of NF-κB and Iba-1 expression, indicating attenuation of oxidative and inflammatory responses. Histopathological and immunohistochemical evaluations confirmed these findings, showing preservation of cortical and brain stem architecture with marked reductions in neuronal necrosis, gliosis, BAX, GFAP, and NLRP3 expression. Collectively, the results demonstrate that Ex-Chit-EGCG NPs exert superior neuroprotective effects compared with exosomes alone, highlighting the therapeutic advantage of combining EGCG with chitosan nanocarriers and exosomal delivery. This dual nanotherapeutic strategy offers a promising and non-invasive approach for mitigating brain aging and holds potential for translation into therapies targeting age-related neurodegenerative disorders. Show less

A converging mechanistic theme across mental disorders involves impaired neuroplasticity and reduced brain-derived neurotrophic factor (BDNF). Glucagon-like peptide-1 receptor agonists (GLP-1RAs), used for type 2 diabetes and obesity, have shown neuroprotective potential, but whether these effects are mediated by BDNF is unclear. This systematic review synthesised molecular evidence linking GLP-1RA administration to BDNF changes and evaluated their contribution to illness progression in neurodegenerative and psychiatric disorders. A systematic search of PubMed, Ovid and Google Scholar from inception to September 6, 2025, identified studies reporting BDNF-related outcomes following GLP-1RA treatment. Eligible studies included primary in vivo or in vitro research on GLP-1RAs in models of neurodegenerative or psychiatric disorders. Risk of bias was assessed using SYRCLE and QUIN tools. The initial search yielded 300 records, of which 18 met the inclusion criteria. Across these studies, GLP-1RAs consistently enhanced BDNF expression and signalling in models of diabetes, neurodegeneration and neurotoxicity, with diabetic models included for their relevance to GLP-1RA pharmacology and shared neuroinflammatory pathway. Reported increases in BDNF expression ranged from 76 % to 377 %, correlating with improved synaptic plasticity, cognition and neuronal survival. In vitro, GLP-1 and exendin-4 increased BDNF expression and axonal transport even under Aβ oligomer exposure. While most neuroprotection aligned with BDNF upregulation, some effects occurred independently through alternative pathways. GLP-1RAs upregulate BDNF in preclinical models, supporting its role as a key mediator of neuroprotection. Despite some BDNF-independent actions, the consistent restoration of neurotrophic support positions BDNF as a central pathway for disease modification. Show less

Acrylamide (ACR), a potential neurotoxin prevalent in carbohydrate-rich foods, poses a significant public health concern. While ACR exposure is known to induce tau phosphorylation and synaptic impairment, the underlying mechanisms remain incompletely understood. The aberrant activation of the protein kinase RNA-like endoplasmic reticulum kinase (PERK)-eukaryotic initiation factor-2α (eIF2α) signaling pathway is emerging as a major common theme in neurodegenerative disorders. This study investigated the role of the PERK-eIF2α signaling pathway in ACR-induced neurotoxicity using human neuroblastoma SH-SY5Y cells. Our results showed that ACR exposure not only significantly increased tau phosphorylation at specific epitopes (Ser Show less