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We investigated the relationship between cerebrospinal fluid (CSF) and plasma biomarkers of inflammation, neurodegeneration, and neurocognitive performance in people with HIV (PWH), using longitudinal samples from two previously published cohorts: ACTG A5090 (virally suppressed on antiretroviral therapy, ART) and A736 (ART-naïve or failing). We analyzed paired CSF and plasma samples, as well as 7-domain standardized neurocognitive test scores, at baseline and 24 weeks. Biomarkers included markers of inflammation (e.g., TNF-α, IL-6, IP-10) and neurodegeneration (e.g., NFL, p-Tau217, Aβ42), which were quantified via high-sensitivity immunoassays. Associations with cognition were tested using regression, mediation, and interaction models. Cross-sectional analyses revealed nominal associations between inflammatory markers and cognitive performance, with plasma IL-6 and IP-10 at baseline, and CSF TNFα at week 24 showing the strongest correlations (p < 0.05, uncorrected); however, none survived correction for multiple comparisons. Conversely, higher CSF Aβ42 and plasma BDNF were positively associated with memory and executive function. Longitudinally, biomarker changes did not significantly predict change in global cognition (ΔNPZ-8); the strongest trend (p-Tau217, ρ = -0.12, p = 0.38) was not statistically significant, and multivariate models failed to identify robust predictors (R These results suggest a potential role of CSF TNFα in mediating the neurocognitive effects of HIV and highlight compartment-specific inflammatory dynamics. Plasma TNFα, GFAP, and NFL may serve as peripheral indicators of CNS pathology, though with only moderate concordance. Astrocyte-tau interactions require cautious interpretation pending replication in larger cohorts. Show less

Luteolin, a flavonoid naturally present in a variety of fruits, vegetables, and medicinal plants, has been recognized as a potentially effective neuroprotective nutraceutical because of its remarkable anti-inflammatory, antioxidant, and neurotrophic properties. Increasing evidence suggests that neuroinflammation and oxidative stress are major contributors to cognitive decline and neuronal degeneration in several prominent neurodegenerative disorders, including Alzheimer's disease (AD), Parkinson's disease (PD), Huntington's disease (HD), and multiple sclerosis (MS). Luteolin significantly inhibits microglial activation, reduces pro-inflammatory cytokine production, modulates the nuclear factor kappa B (NF-κB) and mitogen-activated protein kinase (MAPK) signaling pathways, and enhances Nrf2-mediated antioxidant mechanisms. Furthermore, it promotes synaptic plasticity through brain-derived neurotrophic factor (BDNF)-associated pathways and mitigates the aggregation of pathological proteins, including Aβ, tau, α-synuclein, and mutant huntingtin. Preclinical studies consistently demonstrate substantial improvements in cognitive function, motor performance, demyelination, and neuronal viability in models of AD, PD, MS, and HD. Preliminary clinical observations also indicate prospective advantages for cognitive function, regulation of inflammatory responses, and alleviation of symptoms, particularly concerning AD and MS. Notwithstanding these encouraging outcomes, obstacles persist due to luteolin's restricted bioavailability, ideal dosing parameters, and the translational discrepancies between experimental models and human pathophysiological conditions. In summary, luteolin emerges as a noteworthy candidate for nutraceutical-oriented approaches designed to alleviate neuroinflammation and cognitive deterioration in the context of neurodegenerative diseases. Show less

Stress plays a pivotal role in anxiety-like disorders and cognitive decline. The present study investigated the potential effects of prior royal jelly supplementation and environmental enrichment against stress-induced anxiety-like behaviors, serum corticosterone, hippocampal brain-derived neurotrophic factor (BDNF) levels, and cognitive performance deficits in stressed rats. Male Wistar rats were randomly devised into 8 experimental groups. Rats were subjected to royal jelly (200 mg/kg) via oral gavage, standard environmental enrichment, or combination all for 14 days and control rats received saline in the same period of time. Stress induction was done on the 7th day of treatments by exposure to the restrainer under 10°C. Then open field, elevated plus maze, and inhibitory passive avoidance memory tests were used to explore emotional-cognitive behaviour. Also, corticosterone levels, and hippocampal BDNF expression were measured. Stress resulted in an increase in the serum corticosterone levels, anxiety-like behaviors, and decreased hippocampal BDNF expression which reversed by environmental enrichment and royal jelly treatments. Remarkably, the combined treatment exerts a more pronounced effect on the aforementioned outcomes. Our study strongly proposes a novel emerging therapeutic approach through nutritional interventions, emphasizing the potential of these treatments to mitigate stress-induced anxiety and memory impairments prior to stress exposure. Show less

Central pathophysiological mechanisms underlying cognitive impairment and mood disorders are complex. Traditional Chinese Medicine (TCM)-derived bioactive compounds have significant research value in this field. This study aimed to synthesize current preclinical and emerging clinical evidence on the neuroprotective and psychotropic effects of key TCM constituents, with a particular focus on their roles in modulating neuroinflammatory signalling, synaptic plasticity, oxidative balance and stress-related neuroendocrine pathways. A narrative synthesis of experimental and early clinical studies was conducted, emphasizing mechanistic investigations in rodent models and exploratory human trials. Outcomes of interest included inflammatory cytokine expression, inflammasome activation, redox homeostasis, synaptic signalling pathways, neuroendocrine regulation, behavioural performance and translational pharmaceutical considerations. Multiple TCM constituents attenuate microglial activation and inflammasome signalling, suppressing interleukin-1β, interleukin-6 and tumor necrosis factor-alpha through inhibition of nuclear factor κB and NOD-like receptor pyrin domain-containing 3 pathways. These effects restore redox homeostasis, reduce synaptic loss and improve cognitive and behavioural outcomes in animal models. Concurrently, several compounds enhance synaptic resilience by upregulating brain-derived neurotrophic factor and tropomyosin receptor kinase B signalling, activating downstream mechanistic target of rapamycin complex 1 and cyclic adenosine monophosphate response element-binding protein pathways and preserving synaptic proteins. Key agents, including ginsenosides, baicalin and curcumin, have shown translational promise, with small human trials reporting improvements in depressive symptoms, cognitive function and biomarker profiles. Additionally, TCM compounds modulate HPA axis dynamics by attenuating stress-induced corticosterone elevation, restoring glucocorticoid receptor sensitivity and rebalancing monoaminergic and glutamatergic neurotransmission. However, pharmaceutical translation remains limited by challenges related to formulation, dosage standardization and poor oral bioavailability, particularly for flavonoids and saponins. TCM-derived compounds exert multifaceted neuroprotective and psychotropic effects, while successful clinical translation requires strengthened pharmaceutical characterization, standardized dosing strategies and advanced delivery systems such as nanoformulations, phytosomes and standardized granules to enhance bioavailability, reliability and regulatory acceptance. Show less

Dementia involves progressive cognitive decline, impairing daily and social activities. As no current drugs can reverse this decline, preventive strategies using functional compounds are gaining attention. Rutin, a flavonoid with neuroprotective and vascular benefits, has limited bioavailability due to poor water solubility. Although enzymatic glycosylation improves its solubility, it contains multiple compounds with differing numbers of sugar units and is not a single compound. To address this, EubioQuercetin®, a novel water-soluble rutin (wsRutin) formulation, was developed using L-arginine and ascorbic acid, without enzymatic processing. Here, we evaluated the neuroprotective effects of quercetin and isorhamnetin, the major metabolites of rutin, and compared the cognitive effects of rutin suspension and wsRutin solution in mice. Quercetin and isorhamnetin suppressed glutamate-, menadione- and H Show less

Neuroinflammation driven by dysfunctional microglial responses represents a critical early pathogenic process, particularly in the context of Alzheimer's disease (AD). The natural flavonoid fisetin possesses anti-inflammatory characteristics; however, the exact mechanisms via which it mitigates microglial dysfunction in AD are not fully elucidated. This work employed a combination of in vivo and in vitro approaches, utilizing male APP/PS1 mice and ADDL-stimulated primary microglia. Behavioral tests, immunohistochemistry, molecular profiling, and mitochondrial function assays were conducted. This research combines network pharmacology, molecular docking, and cellular thermal shift assays (CETSA) to offer predictive insights. Fisetin treatment improved cognitive performance in APP/PS1 mice, concurrently reducing amyloid pathology and plaque-associated microglial clustering. In primary microglia, fisetin potently inhibited ADDL-induced pro-inflammatory activation, mitochondrial ROS overproduction, and membrane depolarization. PI3K was identified as a signaling node potentially involved in fisetin-mediated regulation of microglial inflammatory responses. Accordingly, fisetin constrained microglial inflammatory signaling, at least in part through modulation of the PI3K-Akt-NF-κB axis, thereby limiting NF-κB nuclear translocation and pro-inflammatory cytokine release in both the mouse hippocampus and cultured primary microglia. Furthermore, conditioned medium from fisetin-treated microglia alleviated neuronal damage and restored the expression of BDNF and PSD95 in primary neurons. The collective findings, along with experimental studies utilizing the PI3K inhibitor (LY294002), indicate that PI3K may act as a molecular target of fisetin, underscoring its potential therapeutic significance in regulating early inflammatory processes in AD. Show less

Alzheimer's disease (AD) is a neurodegenerative disorder characterized by progressive cognitive decline, in which mitochondrial dysfunction plays a critical role. The mitochondrial calcium uniporter (MCU) is a key regulator of mitochondrial calcium (mCa Show less

Sleep deprivation (SD) is a critical risk factor for cognitive decline and is closely linked to psychiatric disorders. The hippocampal CA2 region is critically involved in encoding social memory and regulating emotional behavior, and it has been implicated in various neuropsychiatric conditions. However, how SD affects CA2-dependent synaptic plasticity and related behaviors remains poorly understood. Here, we subjected mice to 5 h of SD via gentle handling and examined synaptic plasticity, molecular signaling, and social recognition memory. Electrophysiological recordings revealed that SD markedly impaired long-term potentiation (LTP) in CA2 and disrupted social recognition memory, as evidenced by failure to distinguish novel from familiar conspecifics. These deficits were accompanied by upregulation of adenosine A1 receptors and PDE4A5, along with reduced expression of plasticity-related proteins including PKMζ, ERK, and BDNF. Moreover, caffeine-induced synaptic potentiation was diminished in SD mice, whereas caffeine supplementation reversed both synaptic and behavioral impairments. Together, these findings demonstrate that SD compromises CA2-dependent plasticity and social cognition through adenosine receptor signaling and identify CA2 as a vulnerable, therapeutically relevant region. Targeting adenosine pathways may represent a novel strategy to mitigate sleep loss-related cognitive dysfunction in neuropsychiatric disorders. Show less

Alzheimer's disease is a common neurodegenerative disease characterized by progressive memory loss, cognitive decline, and behavioral changes. Blood-based biomarkers have recently gained significant attention due to their accessibility and cost-effectiveness. This review highlights the latest progress in multiple key areas of bloodbased biomarkers for Alzheimer's disease. For early diagnosis, blood-based biomarkers such as amyloid-β and phosphorylated tau can identify Alzheimer's disease even before clinical symptoms emerge. Dynamic changes in blood-based biomarkers, including p-tau217 and neurofilament light chain, reflect disease progression and correlate with cognitive decline, enabling continuous monitoring of Alzheimer's disease progression. Additionally, bloodbased biomarkers such as p-tau181 and glial fibrillary acidic protein aid in differential diagnosis by distinguishing Alzheimer's disease from other dementias such as frontotemporal dementia. Blood-based biomarkers related to nerve repair have opened up new avenues for tracking nerve regeneration and therapeutic response, especially brain-derived neurotrophic factor. Furthermore, advanced detection technologies such as single-molecule array and immunoprecipitation-mass spectrometry have significantly improved the sensitivity and specificity of bloodbased biomarkers, facilitating their clinical translation. In summary, blood-based biomarkers hold strong potential to improve early diagnosis, monitor progression, differential diagnosis, and evaluate therapies in Alzheimer's disease. This review provides a comprehensive and updated evaluation of the translational potential of bloodbased biomarkers, emphasizing their practical utility in clinical settings and offering insights into future directions for large-scale application. This review emphasizes the need to prioritize the allocation of scientific resources, expedite the transition of blood-based biomarkers to clinical implementation, and ultimately achieve precise treatment of Alzheimer's disease using these biomarkers. Show less

Traumatic brain injury (TBI) is a well-recognized risk factor for late-life cognitive decline. However, few studies have examined individual differences in sex and genetics, which may modify risk. We examined sex differences in gene-TBI interactions for dementia risk genes apolipoprotein E (APOE) and selected brain-derived neurotrophic factor (BDNF) single-nucleotide polymorphisms (SNPs) in predicting late-life cognitive decline. We studied 4293 individuals without dementia at baseline (mean age: 74.93, SD: 6.87 years, 57% female). Approximately 25% reported a history of TBI. Linear mixed effects models examined associations between sex, TBI characteristics, APOE genotype, BDNF SNPs and their interactions, with cognitive decline. Compared to males, females experienced fewer TBIs across the lifespan, the majority occurring in late-life. Number of TBI interacted with sex and APOE genotype such that female APOE ε4 allele carriers with multiple TBIs exhibited worse outcomes on global cognition (P < .001; eg, ε4+/TBI2+ estimated marginal means [EMMs] from baseline to year 10 = -17.22 points compared with ε4-/TBI2+ = -7.21), whereas males did not exhibit differential decline by APOE ε4 alleles and TBI number. BDNF Val66Met genotype showed trend-level moderation of TBI history and cognitive decline, with slower decline experienced by heterozygous individuals with multiple TBIs compared with homozygous major allele carriers. There were few significant associations between timing and severity of TBI with cognitive outcomes. These results underscore the importance of considering individual differences of sex and APOE and BDNF-related gene variants on the long-term cognitive effects of TBI. Show less

Type 2 diabetes has been linked to oxidative stress, inflammation, and an imbalance in the gut microbiota, all of which contribute to neuroinflammation and cognitive decline. Gut microbiota influence inflammation and produce various substances, including butyrate, a short-chain fatty acid that promotes brain-derived neurotrophic factor (BDNF), which is essential for memory. This study investigated whether prebiotics, probiotics, or a combination of both (symbiotics) could improve memory in diabetic rats. Male Wistar rats were divided into five groups: control; diabetic and obese (induced by a high-fat diet and streptozotocin); diabetic and obese with prebiotics (inulin); diabetic and obese with probiotics (Lactobacillus acidophilus); and diabetic and obese with symbiotics (inulin + L. acidophilus). Treatments lasted 42 d. Memory performance was evaluated using the Morris water maze (spatial memory) and the Eight-arm radial maze (working memory). After testing, hippocampal tissue was analyzed for inflammatory markers (TNF-α, IL-10), BDNF, and butyric acid. Diabetes impaired memory and increased neuroinflammatory markers. All supplemented groups showed improved memory. The symbiotic group exhibited the most pronounced benefits, with higher levels of BDNF, IL-10, and butyric acid, and reduced TNF-α. Electrophysiological recordings revealed that diabetes reduced the firing frequency of CA1 pyramidal cells and decreased the synaptic strength in the hippocampus. Symbiotic supplementation preserved these neuronal and synaptic functions. Symbiotic treatment effectively countered diabetes-induced cognitive deficits by reducing neuroinflammation, increasing neurotrophic support, and maintaining synaptic plasticity. These results imply that altering the gut microbiota through symbiotic supplementation may be an effective approach to prevent or mitigate diabetes-associated cognitive decline. Show less

Gradual loss of cognitive abilities is common during ageing but might also result in mild cognitive impairment and dementia. Research suggests that neurotrophins, such as brain derived neurotrophic factor (BDNF), and neurosteroids, such as dehydroepiandrosterone (DHEA) and its sulphate (DHEAS), play crucial role in cognitive functions and are often dysregulated in neurocognitive disorders. This study aimed to investigate variations in the genes for BDNF and sulfotransferase 2A1 (SULT2A1), the enzyme converting DHEA into DHEAS, as well as plasma BDNF and DHEAS levels, in individuals with normal cognition, and mild, moderate, and severe cognitive impairment. Cognitive functions of 453 participants were evaluated using Mini-Mental State Examination (MMSE) and Clock Drawing test (CDT). Genotyping of BDNF (rs6265) and SULT2A1 (rs2637125) polymorphisms was conducted, and plasma BDNF and DHEAS concentrations were determined by enzyme-linked immunosorbent assays (ELISA). Obtained results demonstrated that participants with moderate to severe cognitive impairment had significantly lower plasma BDNF and DHEAS levels, compared to individuals with normal cognition. In contrast to DHEAS, BDNF changes were more pronounced in men than in women. However, no significant associations of BDNF rs6265 and SULT2A1 rs2637125 polymorphisms with cognitive decline, or with plasma BDNF and DHEAS levels, respectively, were observed. Compared to CDT, MMSE was superior in distinguishing plasma BDNF and DHEAS variations, especially between individuals with mild and moderate to severe cognitive impairment. Further studies should investigate the potential of BDNF and DHEAS as peripheral biomarkers of cognitive decline and possible benefits of their replacement therapy in neurocognitive disorders. Show less

Aging-related cognitive decline is a major concern in aging societies. Theobromine (TB), a cacao-derived methylxanthine, exerts neuroprotective effects through anti-inflammatory, antioxidant, and neurotrophic mechanisms; however, its efficacy in aging models remains unclear. This study investigated the mechanisms underlying neuroprotective effects of chronic TB administration in senescence-accelerated mouse prone 8 (SAMP8), a model of age-related memory impairment. SAMP8 and SAMR1 mice were fed either a control diet or a diet supplemented with 0.05% TB for 50 d. Cognitive performance was evaluated by the novel object recognition (NOR) test. Neurotrophic factors (BDNF and NT-3), synaptic proteins (PSD95 and synaptophysin), and plasticity-related signaling molecules (phosphorylated CREB and TrkB) were analyzed in the prefrontal cortex and hippocampus. Inflammatory cytokines, lipid peroxides, and antioxidant enzymes were quantified. Molecular docking was used to assess TB's interaction with phosphodiesterase (PDE) enzymes. TB improved short-term memory in SAMP8, increasing discrimination index in the NOR test. This was accompanied by increased BDNF, NT-3, PSD95, and synaptophysin levels and enhanced CREB and TrkB phosphorylation. Furthermore, TB lowered the levels of pro-inflammatory cytokines (IL-1β, TNF-α) and phosphorylated NF-κB, reduced lipid peroxidation, and increased the levels of antioxidant markers (HO-1, GSH). These effects were minimal in SAMR1. No adverse effects on body weight or blood parameters were observed. Molecular docking indicated that TB binds to PDE enzymes with weaker inhibitory activity than selective inhibitors. TB enhances short-term memory and synaptic function in aged mice via neurotrophic, antioxidant, and anti-inflammatory mechanisms, supporting its potential as a safe dietary intervention for age-related cognitive decline. Show less

The integrated stress response (ISR) has been implicated in cognitive decline associated with ageing and neurodegenerative diseases. Pharmacological inhibition of the ISR using the small-molecule ISRIB has demonstrated promising neuroprotective effects in several preclinical models. However, its potential therapeutic value in vascular cognitive impairment (VCI) remains largely unexplored. Here, we established a modified permanent bilateral carotid occlusion (2-VO) rat model of VCI and investigated the therapeutic potential of the ISRIB via microinjection in hippocampal dentate gyrus (DG). VCI rats exhibited elevated expression of vascular endothelial growth factor (VEGF), cluster of differentiation 34 (CD34), ionized calcium-binding adapter molecule 1 (Iba1), interleukin-1 beta (IL-1β), and interleukin-6 (IL-6), indicating successful establishment of the model. Behavioral assessments revealed that VCI rats exhibited impaired spatial, working, and recognition memory. Bioinformatic analysis highlighted ISR pathway activation in VCI. Furthermore, elevated phosphorylated eukaryotic initiation factor 2 alpha (p-eIF2α) and activating transcription factor 4 (ATF4) protein levels in the DG confirmed ISR activation in the DG of VCI rats. VCI also reduced neuronal integrity, as evidenced by decreased Nissl body density. ISRIB treatment significantly improved cognitive performance, suppressed ATF4 expression, enhanced puromycin-labeled protein synthesis, and restored phosphorylated cAMP response element-binding protein (p-CREB) and brain-derived neurotrophic factor (BDNF) signaling. Notably, ISRIB increased c-fos activation and upregulated synaptophysin and postsynaptic density protein 95 (PSD95) expression in the DG of VCI rats, indicating enhanced neuronal activity and synaptic function. Our results indicate that ISR activation contributes to hippocampal-dependent memory impairment in VCI. ISRIB effectively restores synaptic function and cognition, underscoring its therapeutic value and translational potential in treating VCI. Show less