Neuroinflammation in Alzheimer's disease: Current evidence and future directions

Identification of a novel pyrrolo[2,3-b]pyridine compound as a potent glycogen synthase kinase 3β inhibitor for treating Alzheimer's disease

Herein, a novel pyrrolo[2,3-b]pyridine-based glycogen synthase kinase 3β (GSK-3β) inhibitor, S01, was rationally designed and synthesised to target Alzheimer's disease (AD). S01 inhibited GSK-3β, with an IC50 of 0.35 ± 0.06 nM, and had an acceptable kinase selectivity for 24 structurally similar kinases. Western blotting assays indicated that S01 efficiently increased the expression of p-GSK-3β-Ser9 and decreased p-tau-Ser396 levels in a dose-dependent manner. In vitro cell experiments, S01 showed low cytotoxicity to SH-SY5Y cells, significantly upregulated the expression of β-catenin and neurogenesis-related biomarkers, and effectively promoted the outgrowth of differentiated neuronal neurites. Moreover, S01 substantially ameliorated dyskinesia in AlCl3-induced zebrafish AD models at a concentration of 0.12 μM, which was more potent than Donepezil (8 μM) under identical conditions. Acute toxicity experiments further confirmed the safety of S01 in vivo. Our findings suggested that S01 is a prospective GSK-3β inhibitor and can be tested as a candidate for treating AD.

Exploring the connection between dementia and cardiovascular risk with a focus on ADAM10

Alzheimer's disease (AD) represents a leading cause of dementia, characterized by progressive cognitive and functional decline. Although extensive research has unraveled critical aspects of AD pathology, its etiology remains incompletely understood, urging further exploration into potential risk factors. Growing evidence underscores a significant link between cardiovascular disease (CVD) risk factors and AD, with modifiable lifestyle elements - such as physical inactivity, high low-density lipoprotein (LDL) levels, obesity, hypertension, atherosclerosis, and diabetes - emerging as contributors to cerebrovascular damage and neurodegeneration. ADAM10, a disintegrin and metalloproteinase involved in the non-amyloidogenic processing of amyloid precursor protein (APP), has garnered interest for its dual role in cardiovascular and neurodegenerative processes. ADAM10's regulation of neuroinflammation, endothelial function, and proteolytic cleavage of APP potentially moderates amyloid-β (Aβ) peptide formation, thus influencing both cardiovascular and brain health. Given these interconnected roles, this narrative review investigates whether ADAM10-driven vascular dysfunction accelerates neurodegeneration, how lipid metabolism influences ADAM10 activity in CVD and AD, and whether targeting ADAM10 could offer a dual-benefit therapeutic strategy to mitigate disease burden. By exploring epidemiological data, clinical studies, and molecular pathways, we aim to clarify ADAM10's bridging function between AD and cardiovascular risk, offering a new perspective into therapeutic opportunities to alleviate the dual burden of these interrelated conditions.

Refining the interactions between microglia and astrocytes in Alzheimer's disease pathology

Microglia and astrocytes are central to the pathogenesis and progression of Alzheimer's Disease (AD), working both independently and collaboratively to regulate key pathological processes such as β-amyloid protein (Aβ) deposition, tau aggregation, neuroinflammation, and synapse loss. These glial cells interact through complex molecular pathways, including IL-3/IL-3Ra and C3/C3aR, which influence disease progression and cognitive decline. Emerging research suggests that modulating these pathways could offer therapeutic benefits. For instance, recombinant IL-3 administration in mice reduced Aβ plaques and improved cognitive functions, while C3aR inhibition alleviated Aβ and tau pathologies, restored synaptic function, and corrected immune dysregulation. However, the effects of these interactions are context-dependent. Acute C3/C3aR activation enhances microglial Aβ clearance, whereas chronic activation impairs it, highlighting the dual roles of glial signaling in AD. Furthermore, C3/C3aR signaling not only impacts Aβ clearance but also modulates tau pathology and synaptic integrity. Given AD's multifactorial nature, understanding the specific pathological environment is crucial when investigating glial cell contributions. The interplay between microglia and astrocytes can be both neuroprotective and neurotoxic, depending on the disease stage and brain region. This complexity underscores the need for targeted therapies that modulate glial cell activity in a context-specific manner. By elucidating the molecular mechanisms underlying microglia-astrocyte interactions, this research advances our understanding of AD and paves the way for novel therapeutic strategies aimed at mitigating neurodegeneration and cognitive decline in AD and related disorders.

Unveiling the Involvement of Herpes Simplex Virus-1 in Alzheimer's Disease: Possible Mechanisms and Therapeutic Implications

Viruses pose a significant challenge and threat to human health, as demonstrated by the current COVID-19 pandemic. Neurodegeneration, particularly in the case of Alzheimer's disease (AD), is significantly influenced by viral infections. AD is a neurodegenerative disease that affects people of all ages and poses a significant threat to millions of individuals worldwide. The precise mechanism behind its development is not yet fully understood; however, the emergence and advancement of AD can be hastened by various environmental factors, such as bacterial and viral infections. There has been a longstanding suspicion that the herpes simplex virus-1 (HSV-1) may have a role to play in the development or advancement of AD. Reactivation of HSV-1 could potentially lead to damage to neurons, either by direct means or indirectly by triggering inflammation. This article provides an overview of the connection between HSV-1 infections and immune cells (astrocytes, microglia, and oligodendrocytes) in the progression of AD. It summarizes recent scientific research on how HSV-1 affects neurons, which could potentially shed light on the clinical features and treatment options for AD. In addition, the paper has explored the impact of HSV-1 on neurons and its role in various aspects of AD, such as Aβ secretion, tau hyperphosphorylation, metabolic dysregulation, oxidative damage, apoptosis, and autophagy. It is believed that the immune response triggered by HSV-1 reactivation plays a role in the development of neurodegeneration in AD. Despite the lack of a cure for AD, researchers have made significant efforts to study the clinical and pathological aspects of the disease, identify biomarkers, and gain insight into its underlying causes. The goal is to achieve early diagnosis and develop treatments that can modify the progression of the disease. The current article discusses the most promising therapy for combating the viral impacts, which provides additional evidence for the frequent reactivations of latent HSV-1 in the AD brain. However, further research is still required to establish the molecular and cellular mechanisms underlying the development of AD through the reactivation of HSV-1. This could potentially lead to new insights in drug development aimed at preventing HSV-1 reactivation and the subsequent development and progression of AD.

Regional brain structural alterations in reward and salience networks in asthma

INTRODUCTION

Chronic systemic inflammation is highly prevalent and has deleterious effects on the brain, impacting both function and structure, and manifesting in elevations in psychological symptoms transdiagnostically. Asthma is a chronic inflammatory disease of the airway that affects more than 300 million people worldwide and is known to be highly comorbid with psychological and cognitive dysfunction. Though a growing corpus of work has identified functional brain abnormalities associated with asthma, limited research has investigated structural differences which may partially underlie functional changes. Identifying and characterizing asthma-related structural brain changes will shed light on the neurobiology through which asthma impacts mental function and has the potential to inform prophylaxis and treatment.

METHODS

We examined differences in regional brain volume, cortical thickness, and surface area, in 128 individuals with asthma compared to 134 non-asthma healthy controls. Five regions of interest were examined a priori, based on their previous implication in inflammation-related functional consequences (dorsal and ventral striatum, pallidum, and insula), or previous evidence of asthma-related structural impact (hippocampus and thalamus). We supplemented our region of interest approach with a voxel-wise whole-brain analysis. Additionally, we examined the association of brain structure with depression symptoms, asthma severity, degree of inflammation, and plasma biomarkers of neuroinflammation, neurodegeneration, and Alzheimer's disease specific pathology.

RESULTS

Compared to non-asthma control participants, those with asthma had smaller nucleus accumbens volumes, thicker orbitofrontal cortices, larger middle frontal cortex surface areas, and greater diencephalon volumes. Those with more severe asthma had smaller nucleus accumbens and dorsal striatal volumes, reduced anterior cingulate cortex surface area, and greater amygdala volume compared to those with mild asthma. In untreated asthma patients, greater depressive symptoms were associated with smaller striatal volume, suggesting a potential CNS-protective effect of medications that reduce airway inflammation in asthma. In addition, a plasma marker of astrogliosis was associated with larger diencephalon, cerebellum, brainstem, and thalamus volumes, but reduced insula thickness and surface area.

CONCLUSIONS

Patterns of structural brain changes in participants with asthma encompass key regions of reward and salience networks, which may in part give rise to the functional alterations in these networks characteristic of chronic systemic inflammation.

C-reactive protein-mediated dementia

Loss of memory is the main feature of dementia, accompanied by personality changes. Alzheimer's disease (AD) is the most prevalent type of dementia globally and a major contributor to disability and mortality in older individuals. Most notably, the neurological damage caused by AD is irreversible, but the current market still lacks effective medications for the treatment of dementia. Numerous research studies have indicated that the inflammatory response is significantly involved in the development of cognitive impairment, and elevated C-reactive protein (CRP) levels in healthy people increases the likelihood of future AD. CRP is a nonspecific indicator of inflammation. In clinical practice, CRP has long been proven to be one of the risk factors and powerful predictors of neurodegenerative diseases. Given the accessibility and cost-effectiveness of CRP testing, it is reasonable to anticipate its utilisation for early screening and monitoring the progression of AD in the future. This review therefore focuses on the specific relationship between CRP and various types of dementia and explores how CRP contributes to cognitive impairment.

Causal relationship between hippocampal subfield volume and alzheimer's disease: a mendelian randomization study

BACKGROUND AND OBJECTIVE

Numerous studies suggest that the development of Alzheimer's Disease (AD) leads to a reduction in overall hippocampal volume. However, there is limited research exploring whether pre-morbid differences in hippocampal volume impact the risk of AD. This study aims to delve into the causal relationship between hippocampal subregional volume and AD using bidirectional Mendelian Randomization (MR) methods.

METHODS

We extracted 44 instrumental variables for hippocampal subregional volume from the GWAS Catalog, involving 21,282 European individuals. Data on Alzheimer's Disease were sourced from the Psychiatric Genomics Consortium, comprising 1,126,563 European individuals. Rigorous methods were employed to select instrumental variables, with the primary analysis conducted using the Inverse Variance Weighted method. Several sensitivity analyses included tests for heterogeneity, pleiotropy, and outliers. The obtained SNPs were mapped to genes for pathway enrichment analysis to explore the potential mechanisms underlying the regulation of hippocampal volume in Alzheimer's disease.

RESULTS

The study found significant causal associations between increased volume of the 5 hippocampal subfields with increased risk of AD. Conversely, increased Left hippocampus amygdala-transition-area volume was associated with reduced risk of AD. In reverse MR, AD was found to decrease the volume of 8 hippocampal subfields, while increasing the volume of the left hippocampal-fissure region. Amyloid-beta formation, leukocyte activation, and positive regulation of immune response mediated the changes in hippocampal subregional volume due to AD.

CONCLUSION

This MR study provides evidence that AD is causally related to hippocampal subfield volume, highlighting the roles of amyloid-beta formation and immune alterations in this context.

Combining GWAS Summary Data and Proteomics Identified Potential Drug Targets in Dementia

Due to progressive cognitive loss and subsequent incapability of daily life, the development of novel therapeutics is urgently needed for dementia patients. We performed a two-sample bi-directional Mendelian randomization (MR) analysis using summary-level statistics to identify causality between peripheral and cerebrospinal fluid (CSF) proteins and the risk of dementia. Genetic variants were subtracted from the Genome-Wide Association Studies (GWAS) results. Wald ratio (WR) and inverse-variance weighted (IVW) ratio were utilized to estimate the causal effects of plasma and CSF proteins on dementia. Reverse MR, Steiger filtering, Bayesian co-localization phenotype scanning, and external validation were integrated to strengthen the robustness of primary MR results. After sensitivity analysis, six circulating proteins were identified in three dementia classifications, whereas no causality was found in frontotemporal dementia (FTD). Elevated levels of circulating C1R protein increased the odds of developing Alzheimer's disease (AD), while PILRA and CELA2A were estimated to protect against the pathogenesis of AD; genetically predicted increase of α-synuclein and APOE elevated the occurrence of Dementia of Lewy Bodies (DLB); elevated level of circulating CRP was assessed to increase the onset of vascular dementia (VD). Our MR analyses identified a genetically predicted association between circulating C1R, PILRA, and CELA2A and the risk of AD, causal estimates between α-syn, APOE protein, and the onset of DLB, and a robust correlation between CRP and the etiology of VD. This study might guide the discovery of disease etiology and build up a novel disease-modifying paradigm of dementia.

Cerebrospinal fluid inflammatory cytokines as prognostic indicators for cognitive decline across Alzheimer's disease spectrum

BackgroundNeuroinflammation actively contributes to the pathophysiology of Alzheimer's disease (AD); however, the value of neuroinflammatory biomarkers for disease-staging or predicting disease progression remains unclear.ObjectiveTo investigate diagnostic and prognostic utility of inflammatory biomarkers in combination with conventional AD biomarkers.MethodsData from 258 participants in the Alzheimer's Disease Neuroimaging Initiative (ADNI) with cerebrospinal fluid (CSF) biomarkers of amyloid-β (Aβ), tau, and inflammation were analyzed. Clinically meaningful cognitive decline (CMCD) was defined as a ≥ 4-point increase on the Alzheimer's Disease Assessment Scale Cognitive Subscore 11. Predictor variables included demographics (D: age, sex, education), APOE4 status (A), inflammatory biomarkers (I), and classic AD biomarkers of Aβ and p-tau181 (C). Models incorporating inflammatory biomarkers assessed their contribution to improving baseline diagnostic classification and 1-year CMCD prediction.ResultsAt 1-year follow-up, 27.1% of participants experienced CMCD. Adding inflammatory biomarkers to models with D and A variables (DA model) improved classification of cognitively normal (CN) versus mild cognitive impairment (MCI) and CN versus Dementia (p < 0.001). Similarly, inflammatory markers enhanced classification in models including C (DAC model), for CN versus MCI (p < 0.01) and CN versus Dementia (p < 0.001). Predictive performance for CMCD was improved in individuals with MCI and dementia in both models (all p < 0.05). In addition, the DAI model outperformed the DAC model in predicting CMCD for MCI and Dementia groups (both p < 0.05).ConclusionsAddition of CSF inflammatory biomarkers to biomarkers of AD improves diagnostic accuracy of clinical disease stage at baseline and add incremental value to AD biomarkers for prediction of cognitive decline.

The effect of C-reactive protein and interleukin-3 on mild cognitive impairment with APOE ɛ4

BackgroundThe apolipoprotein E ε4 allele (APOE ε4) and inflammation are associated with Alzheimer's disease (AD) pathology. Mild cognitive impairment (MCI) is considered the preclinical and early stage of AD. However, the comprehensive effects of APOE ε4 and inflammatory mediators on MCI patients with specific APOE ε4 genotypes remain poorly understood.ObjectiveOur study aimed to explore how different numbers of the APOE ε4 alleles affect plasma C-reactive protein (CRP) and interleukin-3 (IL-3) levels and their associations with brain structure.MethodsA total of 339 MCI patients from the Alzheimer's Disease Neuroimaging Initiative study were enrolled. We compared their plasma concentrations of CRP and IL-3, cognitive performance, and cerebrospinal fluid (CSF) AD biomarkers levels across different APOE ε4 genotypes. Structural magnetic resonance imaging was utilized to measure gray matter volume outcomes. Pearson correlation analysis was used to explore the associations between the above indicators.ResultsPlasma CRP levels increased in the APOE ε4 carriers, but IL-3 expression notably decreased, and the homozygous state is the most significant. A negative correlation between CRP and several cognitive abilities was observed only in APOE ε4 homozygotes. Additionally, a positive correlation between IL-3, cognitive scores, and CSF biomarker levels was confirmed only in APOE ε4 homozygotes. Imaging data demonstrated that the gray matter volume of the right middle frontal gyrus was associated with CRP only in APOE ε4 non-carriers.ConclusionsOur study demonstrated that peripheral inflammatory mediators' effect on cognitive function and brain structure in MCI patients differs based on their APOE ε4 allele carrier status.

Blockage of CCL3 with neutralizing antibody reduces neuroinflammation and reverses Alzheimer disease phenotypes

BACKGROUND

Accumulating evidence indicates that neuroinflammation is involved in the pathogenesis of Alzheimer's disease (AD). According to RNA sequencing and quantitative PCR (qPCR), we found that chemokine CCL3 mRNA expression was abnormally upregulated in the brains of AD transgenic mice. Moreover, the levels of CCL3 in the serum of AD patients were significantly elevated and negatively correlated with their cognitive abilities. However, the role of CCL3 in AD neuroinflammation and pathological damages remains elusive.

METHODS

Using behavioral, histological, and biochemical methods, outcomes of CCL3 antibody treatment on neuropathology and cognitive deficits were studied in the APPswe/PS1dE9 mice.

RESULTS

In the present study, we reported that CCL3 protein expression was increased in the APPswe/PS1dE9 mice, whereas blockage of CCL3 with neutralizing antibody potently inhibited CCL3 activation in the APPswe/PS1dE9 mice down to the levels of wild-type mice. Specifically, CCL3 antibody significantly improved the learning and memory abilities of APPswe/PS1dE9 mice. In addition, CCL3 antibody treatment decreased cerebral amyloid-β (Aβ) levels and plaque burden via inhibiting amyloid precursor protein (APP) processing by reducing beta-site APP cleaving enzyme 1 (BACE1) expression in the APPswe/PS1dE9 mice. We also found that CCL3 antibody treatment alleviated neuroinflammation and reduced synaptic defects in the APPswe/PS1dE9 mice. Furthermore, the activated NF-κB signaling pathway in APPswe/PS1dE9 mice was inhibited by CCL3 antibody treatment.

CONCLUSIONS

Collectively, our findings provide evidence that CCL3 activation may contribute to the AD pathogenesis and may serve as a novel therapeutic target in the treatment of AD.

Huang-Lian-Jie-Du decoction alleviates cognitive deficits in Alzheimer's disease model 5xFAD mice by inhibiting Trem2/Dap12 signaling pathway

BACKGROUND

Alzheimer's disease (AD) is a progressive neurodegenerative disorder predominantly affecting the elderly population. It is characterized by cognitive deficits associated with the accumulation of amyloid-beta plaques and neurofibrillary tangles. Huang-Lian-Jie-Du (HLJD) decoction, recognized as a representative formulation with heat-clearing and detoxification effects, has been demonstrated to be effective in treating AD. However, the underlying mechanisms require further investigation.

METHODS

5xFAD mice were administrated low and high doses of HLJD. The Morris water maze test was conducted to assess the effects of HLJD. Aβ42 and total tau protein levels were evaluated. Additionally, network pharmacology analysis was performed to identify therapeutic targets of HLJD's active components and their relevance to AD. ELISA, qPCR, Western Blot, and immunofluorescence assays were employed to confirm the identified pathways. Finally, primary microglia isolated from 5xFAD mice were used to validate the candidate targets of HLJD.

RESULTS

HLJD improved cognitive deficits in 5xFAD mice and reduced amyloid plaque deposition and tau protein levels. Network pharmacology analysis indicated that HLJD influences the neuroinflammatory response, particularly through the Dap12 signaling pathway. This was confirmed by reduced levels of neuroinflammation markers, including TNF-α, IL-1β, IL-6, and indicators of microglial activation and polarization. The expression of Trem2 and Dap12 in the hippocampus (HIP) of 5xFAD mice, as well as in the isolated primary microglia, were downregulated following HLJD treatment.

CONCLUSION

Our study indicates that HLJD alleviates cognitive deficits in AD by suppressing the Trem2/Dap12 signaling pathway in the HIP of 5xFAD mice, thereby inhibiting microglial neuroinflammation.

Machine learning determines the incidence of Alzheimer's disease based on population gut microbiome profile

The human microbiome is a complex and dynamic community of microbes, thought to have symbiotic benefit to its host. Influences of the gut microbiome on brain microglia have been identified as a potential mechanism contributing to neurodegenerative diseases, such as Alzheimer's disease, motor neurone disease and Parkinson's disease (Boddy SL, Giovannelli I, Sassani M, et al. The gut microbiome: A key player in the complexity of amyotrophic lateral sclerosis (ALS). BMC Med. 2021;19(1):13). We hypothesize that population level differences in the gut microbiome will predict the incidence of Alzheimer's disease using machine learning methods. Cross-sectional analyses were performed in R, using two large, open-access microbiome datasets (n = 959 and n = 2012). Countries in these datasets were grouped based on Alzheimer's disease incidence and the gut microbiome profiles compared. In countries with a high incidence of Alzheimer's disease, there is a significantly lower diversity of the gut microbiome (P < 0.05). A permutational analysis of variance test (P < 0.05) revealed significant differences in the microbiome profile between countries with high versus low incidence of Alzheimer's disease with several contributing taxa identified: at a species level Escherichia coli, and at a genus level Haemophilus and Akkermansia were found to be reproducibly protective in both datasets. Additionally, using machine learning, we were able to predict the incidence of Alzheimer's disease within a country based on the microbiome profile (mean area under the curve 0.889 and 0.927). We conclude that differences in the microbiome can predict the varying incidence of Alzheimer's disease between countries. Our results support a key role of the gut microbiome in neurodegeneration at a population level.

Prolonged 5-week and 12-week chronic stress differentially modulates CNS expression of pro- and anti-neuroinflammatory biomarkers, brain monoamines and affective behavior in adult zebrafish

Chronic stress is a major cause of affective pathogenesis, such as anxiety and depression. Experimental animal models, including rodents and zebrafish, are a valuable tool for translational neuroscience research focusing on stress-related brain disorders. Here, we examined the effects of 5- and 12-week chronic unpredictable stress (CUS5 and CUS12) on zebrafish behavior, whole-body cortisol and neuroinflammation-related biomarker gene expression, including markers of pro-inflammatory microglia (NOS2a, COX2, P75NTR) and astroglia (C3, GBP), and markers of anti-inflammatory microglia (ARG-1, CD206) and astroglia (S100a10, PTX). We also assessed stress-induced changes in brain monoamine levels and brain-blood-barrier permeability. Overall, CUS5 induced anxiety-like behavior, accompanied by elevated CNS pro-inflammatory marker gene expression, cortisol signaling and norepinephrine levels. In contrast, CUS12 induced depression-like behavior, accompanied by lowered cortisol levels, impaired serotonin turnover and activated anti-inflammatory biomarker gene expression, as well as upregulated histone deacetylase 4 gene (suggesting the involvement of epigenetic regulation). Collectively, this confirms the importance of stress duration as a key factor in the development of stress-related disorders in zebrafish models, and further implicates pro- and inti-inflammatory neuroglia in affective pathogenesis.

Structural characterization and anti-neuroinflammatory activity of polysaccharides isolated from the leaves of Perilla frutescens

In this study, the effect of crude polysaccharide (PF50) from the leaves of Perilla frutescens on the levels of inflammatory mediator proteins was evaluated through Western blotting and immunofluorescence analysis. The results showed that PF50 exerted potent anti-neuroinflammatory effects by significantly suppressing the NO release and expression of the proinflammatory cytokine mediators. Importantly, the PF50 concentration is independently protected against lipopolysaccharide (LPS)-triggered microglial activation-mediated neurotoxicity via inhibiting ROS production and improving mitochondrial function. To further investigate the active ingredients of PF50, a novel polysaccharide (PFP50-1) was purified and its anti-inflammatory activity was studied. PFP50-1 is composed of → 6) - β - D-Galp - (1 →, → 3,6) - α - D-Man p - (1 →, α - L-Araf - (1 →, → 4,6) - α-D-Glcp - (1 →, → 2,3,4) - α - L-Rhap - (1→ and β - D-Glcp - (1 →, which significantly reduced the abnormal elevation of proinflammatory cytokines in LPS-induced BV2 cells. Further experiments revealed that PFP50-1 inhibited the expression of proinflammatory mediator proteins including iNOS and COX-2. In summary, PFP50-1 has exhibited markedly anti-neuroinflammatory effects and may be one of the biologically active ingredients in PF50 for its anti-neuroinflammation and neuroprotection.

Dysregulated interleukin networks drive immune heterogeneity in Alzheimer's disease: an immunogenomic approach to subgroup classification and predictive modeling

BACKGROUND

Alzheimer's Disease (AD) is marked by intricate immunological alterations, including the dysregulation of interleukin signaling. This study investigates the differential expression and potential roles of interleukins and their receptors in AD patients.

METHODS

We analyzed the GSE48350 dataset to assess the single-sample Gene Set Enrichment Analysis (ssGSEA) scores for interleukins and their receptors between normal and AD groups. Differentially expressed interleukin-related genes (DIGs) were identified. Enrichment analysis was conducted to understand functional implications. LASSO and logistic regression were used to identify key interleukin genes, which were employed to construct a predictive nomogram. This model was validated using the GSE132903 dataset. Unsupervised clustering and immune cell infiltration analyses were performed to examine AD patient heterogeneity.

RESULTS

The ssGSEA scores indicated significantly elevated interleukin and receptor levels in AD patients. A total of 23 DIGs were discovered, and the enrichment analysis emphasized their participation in immune signaling pathways. The nomogram based on key interleukin genes demonstrated strong predictive capability, with an AUC of 0.882 in the training set and 0.837 in the validation set. Unsupervised clustering revealed two AD subgroups with distinct immune profiles and pathway activities. Subgroup C2 exhibited higher immune cell infiltration and pathway activity than subgroup C1.

CONCLUSION

Interleukins and their receptors are significantly upregulated in AD patients, with distinct immune profiles identified in AD subgroups. The predictive nomogram effectively stratifies AD patients based on interleukin gene expression. These findings provide insights into AD's immunological landscape and suggest potential biomarkers for personalized therapeutic strategies.

Danggui Shaoyao San ameliorates Alzheimer's disease by regulating lipid metabolism and inhibiting neuronal ferroptosis through the AMPK/Sp1/ACSL4 signaling pathway

Introduction

Alzheimer's disease (AD) is a neurodegenerative disorder characterized by cognitive decline; recent studies suggest that neuronal ferroptosis plays a key role in its pathogenesis. Danggui Shaoyao San (DSS), a traditional Chinese medicine formula, has shown demonstrated neuroprotective effects, but its precise mechanisms in AD treatment remain unclear. This study aims to investigate the mechanism of DSS in treating AD by inhibiting neuronal ferroptosis, explore whether DSS alleviates AD by suppressing neuronal ferroptosis via the AMPK/Sp1/ACSL4 pathway.

Methods

Chemical composition of DSS was identified by LC-MS/MS, followed by network pharmacology to predict targets and pathways. Molecular docking assessed binding affinities between DSS compounds and key proteins (AMPK, Sp1, ACSL4). In vivo experiments on APP/PS1 mice evaluated DSS effects on cognitive function, oxidative stress markers, lipid peroxidation, and ferroptosis-related proteins.

Results

Network pharmacology analysis suggested that DSS regulates lipid metabolism and inhibits neuronal ferroptosis via the AMPK pathway. Molecular docking revealed strong binding affinities between DSS compounds and AMPK downstream proteins, Sp1 and ACSL4. In vivo experiments showed that DSS improved cognitive function, enhanced antioxidant capacity, reduced lipid peroxide accumulation, and decreased Fe2+ content in brain tissue. Furthermore, DSS increased the expression of FTH, p-AMPK, and GPX4 while decreasing Sp1 and ACSL4 levels, thereby inhibiting ferroptosis.

Conclusion

DSS alleviates AD symptoms by suppressing neuronal ferroptosis via the AMPK/Sp1/ACSL4 axis, representing a novel lipid metabolism-targeted therapeutic strategy.

Associations among Angiotensin-Converting Enzyme, Neuroinflammation, and Cerebrospinal Fluid Biomarkers of Alzheimer's Disease in Non-Dementia Adults

Recent studies have identified the angiotensin-converting enzyme (ACE) gene as a potential candidate influencing Alzheimer's disease (AD) risk. It is crucial to investigate the impact of ACE on AD pathology and its underlying mechanisms. A total of 450 non-demented participants from the Alzheimer's disease Neuroimaging Initiative (ADNI) with data on cerebrospinal fluid (CSF) ACE, AD core biomarkers and inflammation-related biomarkers were included. Multiple linear regression was used to assess the associations among CSF ACE, AD core biomarkers and inflammation-related biomarkers. And we used the mediation models to investigate the potential mechanisms through which ACE influenced AD pathology. The results of multiple linear regression were shown that CSF ACE was significantly correlated with CSF Aβ42, P-tau, T-tau (all P < 0.001), and inflammation-related biomarkers (soluble triggering receptor expressed on myeloid cells 2 [sTREM2], progranulin [PGRN], glial fibrillary acidic protein [GFAP], transforming growth factor [TGF]-β1, TGF-β2, TGF-β3, tumor necrosis factor [TNF]-R1, TNF-R2, TNF-α, interleukin [IL]-21, IL-6, IL-7, IL-9, IL-10, IL-12p40, vascular cell adhesion molecule-1 [VCAM-1], and intercellular adhesion molecule-1 [ICAM-1]) (all P < 0.05). In addition, the mediation analysis results showed that the association of CSF ACE and inflammation-related biomarkers (sTREM2, PGRN, TGF-β1, TGF-β2, TNFR1, IL-6, IL-7, IL-9, and VCAM-1) mediated the correlation of CSF Aβ42 with P-tau. Our findings show that CSF ACE and neuroinflammation are correlated and that their correlation mediates the link between Aβ pathology and P-tau. This suggests ACE may play a significant role in the progression from Aβ pathology to tau pathology.

Unraveling the genetic underpinnings of mitochondrial traits and associated circulating inflammatory proteins in Alzheimer's disease: Mitochondrial HtrA2-T cell CD5 negative axis

BackgroundPrevious studies with limited sample sizes have indicated a link between mitochondrial traits, inflammatory proteins, and Alzheimer's disease. The exact causality and their mediation relationships remain unclear.ObjectiveOur study aimed to delve into the genetic underpinnings of mitochondrial function and circulating inflammatory proteins in the pathogenesis of Alzheimer's disease.MethodsWe leveraged aggregated data from the largest genome-wide association study, including 69 mitochondrial traits, 91 circulating inflammatory proteins, and Alzheimer's disease. Bidirectional mendelian randomization (MR) analyses were performed to investigate their primary causal relationships. Thereafter a two-step MR mediation analysis was utilized to clarify the modulating effects of inflammatory proteins on mitochondria and Alzheimer's disease.ResultsOur study identified mitochondrial phenylalanine-tRNA ligase and 4-hydroxy-2-oxoglutarate aldolase as risk factors for Alzheimer's disease, and serine protease HtrA2 and carbonic anhydrase 5A as protective factors against Alzheimer's disease. Four inflammatory proteins (T-cell surface glycoprotein CD5, C-X-C motif chemokine 11, TGF-α, and TNF-related apoptosis-inducing ligand) played protective roles against Alzheimer's disease. Axin-1 and IL-6 increased the risk of Alzheimer's disease. Furthermore, T-cell surface glycoprotein CD5 was found to be a significant mediator between mitochondrial serine protease HTRA2 and Alzheimer's disease with the two-step MR method, accounting for 10.83% of the total effect.ConclusionsOur study emphasized mitochondrial HtrA2-T cell CD5 as a negative axis in Alzheimer's disease, offering novel perspectives on its etiology, pathogenesis, and treatment.

Chitooligosaccharide ameliorates cognitive deficits and neuroinflammation in APP/PS1 mice associated with the regulation of Nrf2/NF-κB axis

Mounting evidence suggests that neuroinflammation is involved in the pathogenesis of neurodegenerative diseases such as Alzheimer's disease (AD). Amyloid β peptide (Aβ) could recruit and activate microglia, leading to the generation of pro-inflammatory factors, and ultimately neuroinflammation. Chitooligosaccharide (COS) is widely recognized as anti-inflammation bioactive substance, though whether it exerts beneficial effect on AD is unclear. In this study, we explored the effect of COS on AD prevention and treatment. We found that COS ameliorated cognitive deficiency, increased the expression of Nrf2 but decreased Aβ levels and the activation of NF-κB in APP/PS1 mice. In vitro, COS decreased the secretions of IL-6, IL-1β and TNF-α in Aβ25-35 + lipopolysaccharides (LPS) -exposed BV2 microglia. Meanwhile, COS down-regulated the expressions of iNOS, COX-2, NLRP3, caspase 1 and the nuclear translocation of NF-κB p65, while upregulated the expressions of Nrf2 and HO-1. Further, COS improved the viability of SK-N-SH cells that exposed to Aβ25-35 + LPS-stimulated microglial conditioned media, and the repressive effect of COS on NLRP3, iNOS, and phospho-NF-κB p65 expressions were markedly compromised upon Nrf2-siRNA transfection. Collectively, COS improved cognitive decline and suppressed neuroinflammation via the Nrf2/NF-κB signaling axis, suggesting COS might be a promising candidate in down-regulating inflammatory responses during AD progression.

Association of Alzheimer's disease biomarkers with low premorbid intellectual functioning in a multi-ethnic community-dwelling cohort: A cross-sectional study of HABS-HD

Background: Individuals with intellectual disability (ID) may have a five-fold increased risk for developing Alzheimer's disease (AD). However, studies investigating brain aging among individuals with ID without Down syndrome (DS) are lacking. To begin addressing this gap, our study utilized word reading, a widely recognized indicator of an individual's premorbid intellectual ability (pIQ), to examine the effects of ID without DS on plasma AD biomarker outcomes. Objective: To investigate the relationship between premorbid intellectual ability (pIQ) and plasma AD biomarkers in individuals with ID without DS, while considering ethnic differences in these associations. Methods: Participants from the Health & Aging Brain Study - Health Disparities (HABS-HD) were categorized into low (z ≤ -2.00) or average (z = 0.00 ± 1.00) pIQ groups based on word reading scores. Plasma biomarkers including Aβ40, Aβ42, Aβ42/40, phosphorylated tau 181 (p-Tau181), neurofilament light chain (NfL), and total tau (t-tau) were assayed using Simoa technology. Results: Individuals with low pIQ exhibited significantly higher levels of p-Tau181 (p < 0.05), NfL (p < 0.05), and t-tau (p < 0.05) compared to those with average pIQ. Stratified analysis by ethnicity revealed differential associations, with Hispanic and non-Hispanic White (NHW) participants showing distinct biomarker profiles relative to non-Hispanic Black (NHB) individuals. Conclusions: The findings demonstrate that low pIQ is a reliable factor associated with plasma AD biomarker outcomes. Ethnicity appears to modulate these associations, suggesting complex interactions between factors driving AD susceptibility across diverse populations. This study highlights the importance of considering both pIQ and ethnicity in neurodegenerative processes, particularly in individuals with non-DS intellectual developmental disability.

Harnessing the power of ginger leaf polysaccharide: A potential strategy to combat Aβ-induced toxicity through the Wnt/β-catenin pathway

Alzheimer's disease (AD) is prevalent in the elderly, with amyloid-β (Aβ) playing a critical role in its progression. Polysaccharides have garnered increasing attention due to their low toxicity and diverse applications in alleviating AD-like symptoms. However, the potential of ginger leaf polysaccharide in mitigating AD-like symptoms has been rarely investigated. In this study, we isolated a polysaccharide (GLP1) from ginger leaf and evaluated its efficacy and underlying mechanisms in alleviating AD-like symptoms using Caenorhabditis elegans and PC12 cells. GLP1 ameliorated AD-like symptoms in C. elegans, as evidenced by a 41.50 % increase in head thrashing frequency and an 87.13 % increase in body bending frequency. Furthermore, GLP1 mitigated cognitive decline by 76.51 %. Additionally, GLP1 enhanced the activity of acetylcholinesterase in C. elegans and maintained the integrity of neural system function. Moreover, GLP1 improved the survival rate of PC12 cells under Aβ induction by activating the Wnt/β-catenin pathway, which also resulted in a reduction in the release of inflammatory factors, specifically IL-1β by 21.15 %, IL-6 by 39.98 %, and TNF-α by 19.66 %. Notably, FITC-labeled GLP1 could be absorbed by PC12 cells. These compelling findings underscored the therapeutic potential of GLP1 in alleviating Aβ-induced AD-like symptoms and supported the advancement of ginger leaf resource utilization.

Review on pathogenesis and treatment of Alzheimer's disease

The rising incidence of Alzheimer's disease (AD) and the associated economic impacts has prompted a global focus in the field. In recent years, there has been a growing understanding of the pathogenic mechanisms of AD, including the aggregation of β-amyloid, hyperphosphorylated tau, and neuroinflammation. These processes collectively lead to neurodegeneration and cognitive decline, which ultimately results in the loss of autonomy in patients. Currently, there are three main types of AD treatments: clinical tools, pharmacological treatment, and material interventions. This review provides a comprehensive analysis of the underlying etiology and pathogenesis of AD, as well as an overview of the current prevalence of AD treatments. We believe this article can help deepen our understanding of the AD mechanism, and facilitate the clinical translation of scientific research or therapies, to address this global problem of AD.

Compensatory enhancement of orexinergic system functionality induced by amyloid-β protein: a neuroprotective response in Alzheimer's disease

Background

Amyloid-β protein (Aβ) accumulation is a defining characteristic of Alzheimer's disease (AD), resulting in neurodegeneration and a decline in cognitive function. Given orexin's well-documented role in enhancing memory and cognition, this study investigates its potential to regulate Aβ-induced neurotoxicity, offering new perspectives into AD management.

Methods

This paper simulated Aβ accumulation in the hippocampus of AD patients by administering Aβ1-42 oligomers into the bilateral hippocampal dentate gyrus of ICR mice. Inflammatory cytokines (IL-6, TNF-α) and orexin-A levels were measured by ELISA. Additionally, the excitability of orexinergic neurons was assessed by IHC targeting c-Fos expression. These methodologies evaluated the Aβ-induced neuroinflammation, orexinergic system functionality, and dexamethasone's (Dex) effects on these processes.

Results

Injection of Aβ1-42 oligomer resulted in elevated levels of IL-6, TNF-α, and orexin-A in the hippocampus, as well as increased excitability of orexinergic neurons in the lateral hypothalamus (LH). Dex treatment reduced neuroinflammation, causing a reduction in orexin-A levels and the excitability of orexinergic neurons.

Conclusion

Aβ-induced neuroinflammation is accompanied by enhanced levels of orexin-A and orexinergic neuron excitability. These findings suggest that the enhanced functionality of the orexinergic system may become a compensatory neuroprotective mechanism to counteract neuroinflammation and enhance cognitive function.

Berberine Exerts Neuroprotective Effects in Alzheimer's Disease by Switching Microglia M1/M2 Polarization Through PI3K-AKT Signaling

Berberine (BBR), a small molecule protoberberine isoquinoline alkaloid, is easy to cross the blood-brain barrier and is a potential drug for neurodegenerative diseases. Here, we explored the role and molecular mechanism of BBR in Alzheimer's disease (AD) progression. Weighted gene co-expression network analysis (WGCNA) was conducted to determine AD pathology-associated gene modules and differentially expressed genes (DEGs) were also identified. GO and KEGG analyses were performed for gene function and signaling pathway annotation. Cell counting kit-8 (CCK8) assay was applied to analyze cell viability. Immunofluorescence (IF) staining assay was conducted to measure the levels of polarization markers. The production of inflammatory cytokines was analyzed by enzyme-linked immunosorbent assay (ELISA). Reactive oxygen species (ROS) level and mitochondrial membrane potential (MMP) were detected using a ROS detection kit and a MMP Detection Kit (JC-1), respectively. AD pathology-associated DEGs were applied for GO function annotation and KEGG enrichment analysis, and the results uncovered that AD pathology was related to immune and inflammation. Lipopolysaccharide (LPS) exposure induced the M1 phenotype of microglia, and BBR suppressed LPS-induced M1 polarization and induced microglia toward M2 polarization. Through co-culture of microglia and neuronal cells, we found that BBR exerted a neuro-protective role by attenuating the injury of LPS-induced HMC3 on SH-SY5Y cells. Mechanically, BBR switched the M1/M2 phenotypes of microglia by activating PI3K-AKT signaling. In summary, BBR protected neuronal cells from activated microglia-mediated neuro-inflammation by switching the M1/M2 polarization in LPS-induced microglia via activating PI3K-AKT signaling. Key words Alzheimer's Disease, Berberine, Microglia polarization, Neuroinflammation, PI3K-AKT signaling.

Genetics impact risk of Alzheimer's disease through mechanisms modulating structural brain morphology in late life

BACKGROUND

Alzheimer's disease (AD)-related neuropathological changes can occur decades before clinical symptoms. We aimed to investigate whether neurodevelopment and/or neurodegeneration affects the risk of AD, through reducing structural brain reserve and/or increasing brain atrophy, respectively.

METHODS

We used bidirectional two-sample Mendelian randomisation to estimate the effects between genetic liability to AD and global and regional cortical thickness, estimated total intracranial volume, volume of subcortical structures and total white matter in 37 680 participants aged 8-81 years across 5 independent cohorts (Adolescent Brain Cognitive Development, Generation R, IMAGEN, Avon Longitudinal Study of Parents and Children and UK Biobank). We also examined the effects of global and regional cortical thickness and subcortical volumes from the Enhancing NeuroImaging Genetics through Meta-Analysis (ENIGMA) Consortium on AD risk in up to 37 741 participants.

RESULTS

Our findings show that AD risk alleles have an age-dependent effect on a range of cortical and subcortical brain measures that starts in mid-life, in non-clinical populations. Evidence for such effects across childhood and young adulthood is weak. Some of the identified structures are not typically implicated in AD, such as those in the striatum (eg, thalamus), with consistent effects from childhood to late adulthood. There was little evidence to suggest brain morphology alters AD risk.

CONCLUSIONS

Genetic liability to AD is likely to affect risk of AD primarily through mechanisms affecting indicators of brain morphology in later life, rather than structural brain reserve. Future studies with repeated measures are required for a better understanding and certainty of the mechanisms at play.

TBG096 Ameliorates Memory Deficiency in AD Mouse Model via Promoting Neurogenesis and Regulation of Hsc70/HK2/PKM2/LAMP2A Signaling Pathway

In previous studies, we isolated a series of novel gentisides with nerve growth factor (NGF)-mimic activities from Gentiana rigescens Franch and conducted continuous structure-activity relationship (SAR) studies. Recently, a lead compound named TBG096 was discovered with significant NGF-mimic activity, low toxicity, and ability to pass through the blood-brain barrier (BBB). At the cell level, TBG096 exerts NGF-mimic activity by regulation of heat-shock cognate protein 70 (Hsc70) and downstream proteins. Subsequently, high-fat diet (HFD)-induced Alzheimer disease (AD) mouse models were used to evaluate the anti-AD efficacy of the compound. TBG096 significantly improved the memory dysfunction of AD mice at doses of 0.1, 5, and 20 mg/kg, respectively. In order to elucidate the mechanism of action of the compound against AD, the RNA-sequence analysis of transcriptomics, quantitative real-time polymerase chain reaction (qRT-PCR), immunofluorescence staining, and Western blot analysis were performed using animal samples. TBG096 significantly increased the expression of the Wnt gene family (Wnt10b, Wnt5a, and Wnt1) and the number of mature neurons and newborn neurons in the hippocampus and cerebral cortex of AD mice, respectively. At the same time, it reduced the activity of microglia, astrocyte cells, and expression of inducible nitric oxide synthase (INOS) in the brain. Moreover, this compound significantly increased phosphorylated-adenosine 5'-monophosphate-activated protein kinase (AMPK), Hsc70, and lysosomal-associated membrane protein 2a (LAMP2A) and decreased the expression of hexokinase 2 (HK2), pyruvate kinase M2 (PKM2), amyloid precursor protein (APP), microtubule-associated protein tau (Tau), phosphoryl-Tau, and β-amyloid (Aβ) at the protein level. These results suggest that TBG096 produced the NGF-mimic activity and the anti-AD effect via promoting neurogenesis and modification of the Hsc70/HK2/PKM2/LAMP2A signaling pathway, proposing a potential novel approach to counteracting cognitive decline by developing small molecules that promote neurogenesis and the Hsc70 signaling pathway.

Traditional Chinese Medicine-derived formulations and extracts modulating the PI3K/AKT pathway in Alzheimer's disease

Alzheimer's disease (AD) is a common neurodegenerative disorder characterized by memory decline, cognitive impairment, and behavioral abnormalities. Pathologically, AD is marked by neurofibrillary tangles caused by excessive phosphorylation of Tau protein and abnormal deposition of β-amyloid (Aβ) in the brain. The PI3K/AKT signaling pathway plays a crucial role in the development, survival, and metabolic regulation of the central nervous system, particularly in neuronal growth, differentiation, and apoptosis. However, this pathway is often inhibited in AD patients.In recent years, studies have shown that herbal formulations and extracts derived from Traditional Chinese Medicine (TCM) can regulate the PI3K/AKT signaling pathway, thereby improving AD pathological models. This study reviews fundamental research on both active metabolites and compound formulations from TCM for the treatment of AD, targeting the PI3K/AKT signaling pathway.Keywords include "Alzheimer's disease" "AD" "dementia" "PI3K" "AKT" "Traditional Chinese Medicine" "Chinese herbology" "Chinese medicine" and "TCM".The study is based on relevant literature published over the past 15 years, primarily sourced from electronic databases such as Web of Science, PubMed, CNKI, Wanfang, and VIP databases.The findings indicate that herbal formulations and extracts derived from TCM can mitigate AD pathology by regulating the PI3K/AKT signaling pathway, reducing Tau protein phosphorylation and Aβ deposition, inhibiting inflammatory responses and oxidative stress, and alleviating neuronal apoptosis. This study enhances our understanding of the anti-AD mechanisms of TCM through the PI3K/AKT pathway and offers new insights for the future.

Pathological tau activates inflammatory nuclear factor-kappa B (NF-κB) and pT181-Qβ vaccine attenuates NF-κB in PS19 tauopathy mice

Tau regulates neuronal integrity. In tauopathy, phosphorylated tau detaches from microtubules and aggregates, and is released into the extracellular space. Microglia are the first responders to the extracellular tau, a danger/damage-associated molecular pattern (DAMP), which can be cleared by proteostasis and activate innate immune response gene expression by nuclear factor-kappa B (NF-κB). However, longitudinal NF-κB activation in tauopathies and whether pathological tau (pTau) contributes to NF-κB activity is unknown. Here, we tau oligomers from human Alzheimer's disease brain (AD-TO) activate NF-κB in mouse microglia and macrophages reducing the IκBα via promoting its secretion in the extracellular space. NF-κB activity peaks at 9- and 11-months age in PS19Luc + and hTauLuc + mice, respectively. Reducing pTau via pharmacological (DOX), genetic ( Mapt -/- ) or antibody-mediated neutralization (immunization with pT181-Qβ vaccine) reduces NF-κB activity, and together suggest pTau is a driver of NF-κB and chronic neuroinflammation tauopathies.

Summary

Neuronal tau activates microglial NF-κB constitutively by secreting its inhibitor IκBα. NF-κB activation in PS19Luc + and hTauLuc + mice peaks at 9- and 11-months of age, respectively. Neutralizing pTau with pT181-Qβ vaccine (targeting phosphorylated threonine 181 tau) alleviates NF-κB activity in tauopathy mice.

Subcortical tau deposition and plasma glial fibrillary acidic protein as predictors of cognitive decline in mild cognitive impairment and Alzheimer's disease

PURPOSE

This study aimed to investigate the correlation between subcortical tau-positron emission tomography (Tau-PET) and plasma glial fibrillary acidic protein (GFAP) levels and cognitive function in participants with cognitively unimpaired (CU), mild cognitive impairment (MCI) and Alzheimer's disease (AD) conditions.

METHODS

105 participants with amyloid (Aβ) PET and Tau-PET scans were enrolled. Region of interest (ROI) level and voxel-wise comparisons were performed between those three groups. Correlations between standardized uptake value ratio (SUVR) and cognitive performance were analyzed. The diagnostic performance of Tau-PET, Aβ-PET, and plasma GFAP, both individually and combined, was evaluated by calculating the area under the curve (AUC) from receiver operating characteristic (ROC) analyses.

RESULTS

Plasma GFAP levels in the AD and MCI groups were higher than those in the CU group. The AD and MCI groups showed higher Tau-PET load at the amygdala, accumbens, putamen, pallidum, hippocampus, para-hippocampus and olfactory tubercle than the CU group (p < 0.05). In the MCI group, the mean tau SUVR in the combined subcortical ROI negatively correlated with cognitive scores (r = -0.38, p = 0.02). The combination of Tau-PET, Aβ-PET and plasma GFAP provided optimal diagnostic accuracy for classifying AD from MCI, with an AUC of 0.82, a sensitivity of 0.69 and a specificity of 0.81.

CONCLUSIONS

Subcortical tau deposition and increased plasma GFAP levels are associated with cognitive impairment in MCI patients.

Pregnancy as a window of opportunity for dementia prevention: a narrative review

Dementia is a debilitating condition with a disproportionate impact on women. While sex differences in longevity contribute to the disparity, the role of the female sex as a biological variable in disease progression is not yet fully elucidated. Metabolic dysfunctions are drivers of dementia etiology, and cardiometabolic diseases are among the most influential modifiable risk factors. Pregnancy is a time of enhanced vulnerability for metabolic disorders. Many dementia risk factors, such as hypertension or blood glucose dysregulation, often emerge for the first time in pregnancy. While such cardiometabolic complications in pregnancy pose a risk to the health trajectory of a woman, increasing her odds of developing type 2 diabetes or chronic hypertension, it is not fully understood how this relates to her risk for dementia. Furthermore, structural and functional changes in the maternal brain have been reported during pregnancy suggesting it is a time of neuroplasticity for the mother. Therefore, pregnancy may be a window of opportunity to optimize metabolic health and support the maternal brain. Healthy dietary patterns are known to reduce the risk of cardiometabolic diseases and have been linked to dementia prevention, yet interventions targeting cognitive function in late life have largely been unsuccessful. Earlier interventions are needed to address the underlying metabolic dysfunctions and potentially reduce the risk of dementia, and pregnancy offers an ideal opportunity to intervene. This review discusses current evidence regarding maternal brain health and the potential window of opportunity in pregnancy to use diet to address neurological health disparities for women.

Ultrasound-mediated nanomaterials for the treatment of inflammatory diseases

Sterile and infection-associated inflammatory diseases are becoming increasingly prevalent worldwide. Conventional drug therapies often entail significant drawbacks, such as the risk of drug overdose, the development of drug resistance in pathogens, and systemic adverse reactions, all of which can undermine the effectiveness of treatments for these conditions. Nanomaterials (NMs) have emerged as a promising tool in the treatment of inflammatory diseases due to their precise targeting capabilities, tunable characteristics, and responsiveness to external stimuli. Ultrasound (US), a non-invasive and effective treatment method, has been explored in combination with NMs to achieve enhanced therapeutic outcomes. This review provides a comprehensive overview of the recent advances in the use of US-mediated NMs for treating inflammatory diseases. A comprehensive introduction to the application and classification of US was first presented, emphasizing the advantages of US-mediated NMs and the mechanisms through which US and NMs interact to enhance anti-inflammatory therapy. Subsequently, specific applications of US-mediated NMs in sterile and infection-associated inflammation were summarized. Finally, the challenges and prospects of US-mediated NMs in clinical translation were discussed, along with an outline of future research directions. This review aims to provide insights to guide the development and improvement of US-mediated NMs for more effective therapeutic interventions in inflammatory diseases.

Design, current states, and challenges of nanomaterials in anti-neuroinflammation: A perspective on Alzheimer's disease

Alzheimer's disease (AD), an age-related neurodegenerative disease, brings huge damage to the society, to the whole family and even to the patient himself. However, until now, the etiological factor of AD is still unknown and there is no effective treatment for it. Massive deposition of amyloid-beta peptide(Aβ) and hyperphosphorylation of Tau proteins are acknowledged pathological features of AD. Recent studies have revealed that neuroinflammation plays a pivotal role in the pathology of AD. With the rise of nanomaterials in the biomedical field, researchers are exploring how the unique properties of these materials can be leveraged to develop effective treatments for AD. This article has summarized the influence of neuroinflammation in AD, the design of nanoplatforms, and the current research status and inadequacy of nanomaterials in improving neuroinflammation in AD.

Liver-X receptor β-selective agonist CE9A215 regulates Alzheimer's disease-associated pathology in a 3xTg-AD mouse model

In Alzheimer's disease (AD), tau pathology is closely associated with disease progression. Therefore, therapeutics that alleviate tau pathology are essential. Liver-X receptor (LXR) has garnered interest as a potential target for the treatment of AD. We previously investigated the potent anti-allergic and anti-inflammatory effects of inotodiol, hereafter referred to as CE9A215, in various disease models. In this study, we explored the potential of CE9A215 as a treatment for AD. CE9A215 preferentially activated LXRβ (EC50 <10 nM), with no significant activation observed for LXRα at concentrations up to 1000 nM. Pharmacokinetic analysis confirmed that CE9A215 crosses the blood-brain barrier and accumulates in the brain. Moreover, CE9A215 modulated the expression of ABCA1, APOE, SREBP-1c and AQP4 in the brains of wild-type and LXR α/β knockout mice in LXRβ-dependent manner. The efficacy of CE9A215 on AD-related pathologies was evaluated using 3xTg-AD mice. CE9A215 exerted both prophylactic and therapeutic effects on AD-associated behaviors and pathologies, including reductions in amyloid-β, phosphorylated tau, and neuroinflammation in the hippocampus. Transcriptomic analysis revealed that CE9A215 induced significant changes in genes associated with tau pathology, particularly in pathways related to protein phosphorylation and PI3K/AKT signaling. Our findings suggest that CE9A215 could be a promising therapeutic candidate for AD, particularly in mitigating tau hyperphosphorylation and related AD pathologies.

YAP Signaling in Glia: Pivotal Roles in Neurological Development, Regeneration and Diseases

Yes-associated protein (YAP), the key transcriptional co-factor and downstream effector of the Hippo pathway, has emerged as one of the primary regulators of neural as well as glial cells. It has been detected in various glial cell types, including Schwann cells and olfactory ensheathing cells in the peripheral nervous system, as well as radial glial cells, ependymal cells, Bergmann glia, retinal Müller cells, astrocytes, oligodendrocytes, and microglia in the central nervous system. With the development of neuroscience, understanding the functions of YAP in the physiological or pathological processes of glia is advancing. In this review, we aim to summarize the roles and underlying mechanisms of YAP in glia and glia-related neurological diseases in an integrated perspective.

Mild Behavioral Impairment and cognitive functions: A systematic review and meta-analysis

Mild behavioral impairment (MBI) represents a recently introduced diagnostic concept that focuses on behavioral and personality changes occurring in late life and associated with cognitive decline. Nevertheless, the relationship between these dimensions remains unclear. This systematic review and meta-analysis aim to analyze the relationship between MBI and cognitive functioning. The review process was conducted according to the PRISMA-Statement. Restrictions were made, selecting the studies published in peer-review journals, including at least one cognitive measure and presenting the measurement of MBI. Studies that included participants with neurological disorders, dementia, or psychiatric disorders or that only did a neuroimaging or genetic study were excluded. Twenty-two studies were included in the systematic review, while in the meta-analysis seventeen studies featured data to be included in the analyses. The results were classified according to the following cognitive domains: global cognitive functioning, memory, language, attention executive functions, visuospatial skills, and processing speed. In the quantitative analysis, only global cognitive functioning, executive function, attention, and memory were evaluated. The results of both qualitative and quantitative analysis indicate that individuals with MBI exhibited diminished performance on cognitive tasks when compared to those without MBI symptoms. These results are stronger when evaluating the various domains individually (particularly memory and executive functions) than when a global assessment was made. These findings highlight the potential role of MBI symptoms as early indicators of neurodegenerative processes, reinforcing the necessity for comprehensive assessments that encompass both behavioral and cognitive evaluations. The early detection of these symptoms in prodromal phases can be very useful for the development of non-pharmacological interventions and may provide relevant guidelines for clinicians in the management and diagnosis of neurodegenerative disorders.

Peroxisome proliferator-activated receptors (PPARs) agonists as promising neurotherapeutics

Neurodegenerative disorders are characterized by a continuous neurons loss resulting in a wide range of pathogenesis affecting the motor impairment. Several strategies are outlined for therapeutics of synthetic and natural PPARs agonists in some neurological disorders; Parkinson's disease (PD), Alzheimer's disease (AD), Multiple sclerosis (MS), Amyotrophic lateral sclerosis (ALS), and Huntington's disease (HD). The aim of this review is to provide a recent update of the previously reported studies, and reviews dealing with the medicinal chemistry of PPARs and their agonists, and to highlight the outstanding advances in the development of both synthetic compounds including; PPARα agonists (fibrates), PPARγ agonists (thiazolidindiones), and PPARβ/δ agonists either as sole or dual acting PPAR full or pan agonists, in addition to the natural phytochemicals; acids, cannabinoids, and flavonoids for their different neuroprotection effects in the previously mentioned neurodegenerative disorders (PD, AD, MS, ALS, and HD). Moreover, this review reports the diverse pre-clinical and clinical studies of PPARs agonists in the neurodegenerative diseases via cellular, and animal models and human.

CHIT1 regulates the neuroinflammation and phagocytosis of microglia and suppresses Aβ plaque deposition in Alzheimer's disease

Chitinase 1 (CHIT1), as a chitin-specific hydrolase, significantly influences the progression of Alzheimer's disease (AD) through microglia-associated inflammation and amyloid beta (Aβ) plaque accumulation. However, the precise mechanism of CHIT1 action in AD remains uncertain. The effects of CHIT1 on cerebral blood flow (CBF), hippocampal volume, and cognitive function were investigated in APP/PS1 mice. Protein alterations resulting from CHIT1 overexpression were analyzed using four-dimensional (4D) label-free quantitative (LFQ) protein spectrometry. Additionally, the influence of CHIT1 on microglial electrophysiology was assessed using patch clamp measurements, and its effects on neuroinflammation, phagocytosis, microglia migration, and neuronal apoptosis under AD-like conditions were examined using the cell lines N9, BV-2, and HT-22. CHIT1 ameliorated hippocampal atrophy, hypoperfusion, and cognitive function deficits in the APP/PS1 mouse. CHIT1 regulates microglial function and neuronal protection through its interactions in AD. Increased levels of CHIT1/IDH1 contributed to an anti-inflammatory phenotype in microglia via the Ca2+-activated K+ channel, enhanced microglial phagocytosis, and promoted Aβ clearance. Conversely, knocking down IDH1 reduced the secretion of anti-inflammatory agents and increased the production of inflammatory factors, as well as diminishing the expression of phagocytic factors and inhibiting Aβ endocytosis. Moreover, CHIT1 reduced neuronal apoptosis by diminishing the expression of apoptotic factors. However, IDH1 knockdown abrogated the protective effect of CHIT1 on neurons. CHIT1 exerts a protective role in AD pathogenesis through its interaction with IDH1. The CHIT1/IDH1 pathway promotes Aβ clearance via a shift in microglia toward an anti-inflammatory state and prevents neuronal apoptosis and dysfunction caused by Aβ toxicity. © 2025 The Pathological Society of Great Britain and Ireland.

Lactiplantibacillus plantarum GOLDGUT-HNU082 Alleviates CUMS-Induced Depressive-like Behaviors in Mice by Modulating the Gut Microbiota and Neurotransmitter Levels

Emerging evidence links depressive disorders to the gut microbiota via the gut-brain axis. Probiotics, which are microorganisms that modulate the gut microbiota, have shown promising results in alleviating depression and are increasingly recognized as functional food components with potential health benefits. This study examines the effects of Lactiplantibacillus plantarum GOLDGUT-HNU082 (Lp082), a probiotic strain with potential applications in functional foods, on chronic unpredictable mild stress (CUMS)-induced depression in mice. Behavioral tests, measurements of the neurotransmitters and inflammatory cytokines in the serum and colon tissue, and the metagenomic sequencing of the gut microbiota were used to investigate potential mechanisms. The results demonstrated that Lp082 significantly alleviated depressive-like behaviors in CUMS mice, restored the balance of key neurotransmitters like serotonin (5-HT), reduced the levels of inflammatory cytokines like TNF-α, and enhanced brain neuroplasticity by promoting hippocampal neurogenesis. Additionally, Lp082 altered the composition of the gut microbiota in CUMS mice and promoted the growth of Bifidobacterium, improving metabolic pathways related to neurotransmitter synthesis. These findings indicate that Lp082, as a potential functional food ingredient, alleviates depressive-like behaviors in mice by reshaping the gut microbiota, offering new insights into the use of probiotics in functional foods for mental health management.

Nebulized seabuckthorn seed oil inhalation attenuates Alzheimer's disease progression in APP/PS1 mice

Seabuckthorn (Hippophae rhamnoides L.) is known for its medicinal properties in treating various diseases, including neurological conditions. However, the therapeutic effect of inhaled seabuckthorn seed oil (SSO) on Alzheimer's disease (AD) remains not fully understood. This study explores the effects of nebulized inhalation of SSO in 9-month-old APP/PS1 mice over 21 days. The results showed that nebulized SSO improved memory and cognition. Using 7.0T MRI to monitor blood oxygenation level dependent (BOLD) signals revealed that SSO altered the Amplitude of Low Frequency Fluctuations (ALFF) and Regional Homogeneity (ReHo) signaling such as in the amygdala and substantia innominate, and hippocampus. Enzyme-linked immuno sorbent assay (ELISA) and pathological analyses indicated reduced neuroinflammation in plasma and brain, decreased neuronal necrosis, lower β-amyloid (Aβ) protein levels, reduced amyloid deposition, and increased tyrosine hydroxylase activity. Additionally, SSO promoted gut microbiota remodeling by increasing alpha diversity and boosting levels of probiotics such as Verrucomicrobia, Bifidobacterium, Prevotella, and Akkermansia, without adverse effects on lung tissue. Nebulized inhalation of SSO may slow AD progression by modulating inflammation and amyloid deposition. Nebulized inhalation offered a potential method for enhancing drug delivery across the blood-brain barrier with reduced systemic side effects.

Effects of Pesticide Exposure on Neuroinflammation and Microglial Gene Expression: Relevance to Mechanisms of Alzheimer's Disease Risk

Background

Alzheimer's disease (AD) is characterized by the presence of amyloid-β plaques, neurofibrillary tangles, and neuroinflammation. Previously, we reported serum levels of dichlorodiphenyldichloroethylene (DDE), the primary metabolite of the pesticide dichlorodiphenyltrichloroethane (DDT), were significantly higher in AD patients compared to age-matched controls and that DDT exposure worsened AD pathology in animal models.

Objective

Here, we investigated the effect of DDT on neuroinflammation in primary mouse microglia (PMG) and C57BL/6J mice.

Methods

Effects of DDT on inflammation and disease-associated microglia were determined in primary mouse microglia and C57BL/6J mice.

Results

PMG exposed to DDT (0.5-5.0 µM) elicited a ∼2-3-fold increase in Il-1b mRNA levels, with similar concentration-dependent upregulation in Il-6, Nos2, and Tnfa . These effects were blocked by the sodium channel antagonist tetrodotoxin, demonstrating the role of DDT-microglial sodium channel interactions in mediating this response. Additionally, NOS2 protein levels increased by ∼1.5-2-fold, while TNFa was elevated by 2-4-fold. C57BL/6J male and female mice exposed to DDT (30 mg/kg) demonstrated significantly increased mRNA levels of Nos2 , Il-1b , and Il-6 in the frontal cortex (1.5-2.3-fold), and Nos2 , Il-1b, and Tnfa (1.5-1.8-fold) in the hippocampus. Furthermore, microglial homeostatic genes, Cx3cr1 , P2ry12, and Tmem119 , were downregulated, while stage 1 disease-associated microglia genes were upregulated both in vitro and in vivo . Notably, Apoe and Trem2 were only upregulated in the frontal cortex and hippocampus of females.

Conclusion

These data indicate that DDT increases neuroinflammation, which may result from direct actions of DDT on microglia, providing a novel pathway by which DDT may contribute to AD risk.

Fibrinogen-tau Aggregates Exacerbate Tau Pathology and Memory Deficits in Alzheimer's Disease Model Mice

Vascular damage plays a significant role in the onset and progression of Alzheimer's disease (AD). However, the precise molecular mechanisms underlying the induction of neuronal injury by vascular damage remain unclear. The present study aimed to examine the impact of fibrinogen (Fg) on tau pathology. The results showed that Fg deposits in the brains of tau P301S transgenic mice interact with tau, enhancing the cytotoxicity of pathological tau aggregates and promoting tau phosphorylation and aggregation. Notably, Fg-modified tau fibrils caused enhanced neuronal apoptosis and synaptic damage compared to unmodified fibrils. Furthermore, intrahippocampal injection of Fg-modified tau fibrils worsened the tau pathology, neuroinflammation, synaptic damage, neuronal apoptosis, and cognitive dysfunction in tau P301S mice compared to controls. The present study provides compelling evidence linking Fg and tau, thereby connecting cerebrovascular damage to tau pathology in AD. Consequently, inhibiting Fg-mediated tau pathology could potentially impede the progression of AD.

Associations between neutrophil-lymphocyte ratio and risk of cognitive impairment among Chinese older adults

BACKGROUND

Associations between the neutrophil-lymphocyte ratio (NLR) and cognitive performance in older population are rarely reported. We investigated the associations between NLR and risk of cognitive impairment in Chinese community-dwelling older adults.

METHODS

Individuals aged ≥ 65 years from the 2011 and 2014 waves of the Chinese Longitudinal Healthy Longevity Survey were enrolled. We used the Chinese version of the Mini-Mental State Examination to evaluate cognitive function, with a score <18 indicating cognitive impairment. NLR was expressed as derived NLR (white blood cell count - lymphocyte count]/lymphocyte count). Logistic regression was used to evaluate the association between NLR levels and risk of cognitive impairment.

RESULTS

The study enrolled 2375 cognitively healthy participants and 838 with cognitive impairment. Significantly higher NLR values were noted in the latter than in the former group. In the cross-sectional analysis, NLR values in the highest than in the lowest quartile indicated significantly increased risk of cognitive impairment, after controlling for all confounding factors. During follow-up, 134 of the 1173 healthy participants at baseline developed cognitive impairment. NLR values in the highest two quartiles indicated higher risk of cognitive impairment than those in the lowest quartile. When NLR was classified into dichotomous groups, the risk of cognitive impairment was significantly higher in the high-inflammation than in the noninflammatory status group, regardless of the analysis used (cross-sectional or prospective).

CONCLUSIONS

Elevated NLR status is associated with increased risk of cognitive impairment in Chinese community-dwelling older adults.

TREM2 Alleviates Neuroinflammation by Maintaining Cellular Metabolic Homeostasis and Mitophagy Activity During Early Inflammation

AIMS

Inflammation is a pivotal characteristic of neurodegenerative diseases. The triggering receptor expressed on the myeloid cells 2 (TREM2) gene has previously been shown to suppress inflammation by directly inhibiting inflammation-related pathways. Mitochondrial dysfunction has recently emerged as another critical pathological manifestation of neurodegenerative diseases. Although TREM2 is involved in the regulation of cellular energy metabolism and mitochondrial autophagy, its role in the relationship between inflammation and mitochondrial autophagy remains unclear.

METHODS

In this study, we generated TREM2-overexpressing BV-2 cells and established a neuroinflammatory model with LPS. We compared these cells with wild-type cells in terms of inflammation, metabolism, autophagy, and mitochondria using methods such as RT-qPCR, Western blotting, immunocytochemistry, transmission electron microscopy, and flow cytometry.

RESULTS

Microglia overexpressing TREM2 exhibited increased resistance to inflammation. Additionally, these cells inhibited the metabolic reprogramming that occurs early in LPS-induced inflammation, reduced ROS release, mitigated mitochondrial damage, maintained a certain level of autophagic activity, and cleared damaged mitochondria. Consequently, they alleviated the inflammation caused by the mitochondrial barrier.

CONCLUSIONS

ur results suggest that TREM2 can alleviate inflammation by maintaining cellular metabolic homeostasis and mitochondrial autophagy activity.

Critical role of Oas1g and STAT1 pathways in neuroinflammation: insights for Alzheimer's disease therapeutics

BACKGROUND

Alzheimer's disease (AD) has a significant impact on an individual's health and places a heavy burden on society. Studies have emphasized the importance of microglia in the progression and development of AD. Interferon responses and Interferon-stimulated genes (ISGs) significantly function in neuroinflammatory and neurodegenerative diseases involving AD. Therefore, further exploration of the relationship among microglia, ISGs, and neuroinflammation in AD is warranted.

METHODS

Microglia datasets from the GEO database were retrieved, along with additional microglia RNA-seq data from laboratory mice. Weighted Correlation Network Analysis was used on the training dataset to identify gene co-expression networks. Genes from the black module were intersected with interferon-stimulated genes, and differentially expressed genes (DEGs) were identified. Machine learning algorithms were applied to DEGs, and genes selected by both methods were identified as hub genes, with ROC curves used to evaluate their diagnostic accuracy. Gene Set Enrichment Analysis was performed to reveal functional pathways closely relating to hub genes. Microglia cells were transfected with siRNAs targeting Oas1g and STAT1. Total RNA from microglia cells and mouse brain tissues was extracted, reverse-transcribed, and analyzed via qRT-PCR. Proteins were extracted from cells, quantified, separated by SDS-PAGE, transferred to PVDF membranes, and probed with antibodies. Microglia cells were fixed, permeabilized, blocked, and stained with antibodies for STAT1, then visualized and photographed.

RESULTS

Bioinformatics and machine learning algorithms revealed that Oas1g was identified as a hub gene, with an AUC of 0.812. Enrichment Analysis revealed that Oas1g is closely associated with interferon-related pathways. Expression of Oas1g was validated in AD mouse models, where it was significantly upregulated after microglial activation. Knockdown experiments suggested siOas1g attenuated the effect of siSTAT1, and the expressions of STAT1 and p-STAT1 were elevated. siOas1g could reverse the effect of siSTAT1, indicating that Oas1g potentially regulates the ISGs through the STAT1 pathway.

CONCLUSION

We demonstrated that Oas1g was identified as a hub ISG in AD and can downregulate the activation of IFN-β and STAT1, reducing the expression of ISGs in neuroinflammation. Oas1g might potentially be a beneficial candidate for both prevention and treatment of AD.

Recent advances in mRNA-based therapeutics for neurodegenerative diseases and brain tumors

Messenger RNA (mRNA) therapy is an innovative approach that delivers specific protein-coding information. By promoting the ribosomal synthesis of target proteins within cells, it supplements functional or antigenic proteins to treat diseases. Unlike traditional gene therapy, mRNA does not need to enter the cell nucleus, reducing the risks associated with gene integration. Moreover, protein expression levels can be regulated by adjusting the dosage and degradation rates of mRNA. As a new generation gene therapy strategy, mRNA therapy represents the latest advancements and trends in the field. It offers advantages such as precision, safety, and ease of modification. It has been widely used in the prevention of COVID-19. Unlike acute conditions such as cerebral hemorrhage and stroke that often require immediate surgical or interventional treatments, neurodegenerative diseases (NDs) and brain tumors progress relatively slowly and face challenges such as the blood-brain barrier and complex pathogenesis. These characteristics make them particularly suitable for mRNA therapy. With continued research, mRNA-based therapeutics are expected to play a significant role in the prevention and treatment of NDs and brain tumors. This paper reviews the preparation and delivery of mRNA drugs and summarizes the research progress of mRNA gene therapy in treating NDs and brain tumors. It also discusses the current challenges, providing a theoretical basis and reference for future research in this field.

Xinnaoxin capsule alleviates neuropathological changes and cognitive deficits in Alzheimer's disease mouse model induced by D-galactose and aluminum chloride via reducing neuroinflammation and protecting synaptic proteins

ETHNOPHARMACOLOGICAL RELEVANCE

Originally formulated to mitigate high-altitude sickness, Xinnaoxin capsules (XNX) are composed of three traditional Chinese medicines (Rhodiola rosea L., Lycium barbarum L. and Hippophae rhamnoides) with properties of anti-hypoxia, anti-fatigue, and anti-aging. Emerging evidence now suggests that XNX may also offer therapeutic benefits in Alzheimer's disease (AD), highlighting its potential significance in the development of novel AD treatments.

AIM OF THE STUDY

This study aims to investigate whether XNX improves AD-related behavioral and cognitive deficits by enhancing antioxidant defenses, reducing peripheral and neuroinflammation, and protecting neurons.

MATERIALS AND METHODS

The AD mouse model was established using D-galactose and aluminum chloride. Spatial memory and anxiety-like behaviors were assessed via the Morris water maze and open field tests to evaluate the therapeutic effects of XNX. Biochemical markers in hippocampal tissue and serum were measured using ELISA kits, while serum chemical composition was analyzed by LC-MS. Histopathological changes and amyloid-β deposition in the hippocampus were examined through hematoxylin-eosin (HE) staining and immunofluorescence. Additionally, hippocampal expression of apoptotic proteins Bax and Caspase-3, anti-apoptotic protein Bcl-2, and synaptic proteins PSD-95 and Syn were assessed via Western blot.

RESULTS

Behavioral tests demonstrated that XNX significantly improved spatial learning and memory abilities, as well as reduced anxiety-like behaviors in AD mice. XNX also modulated inflammatory cytokines and oxidative stress markers in hippocampal tissue and serum, while reducing amyloid-β deposition. Further LC-MS analysis of serum revealed a marked upregulation of compounds such as adenosine following treatment, with key metabolic pathways affected, including linoleic acid metabolism and phenylalanine, tyrosine, and tryptophan biosynthesis. HE staining and immunofluorescence indicated that XNX ameliorated neuronal damage and decreased amyloid-β accumulation. Western blot analysis confirmed that XNX inhibited neuronal apoptosis and preserved synaptic proteins in the hippocampus.

CONCLUSION

XNX mitigates AD-induced behavioral and cognitive deficits by enhancing antioxidant defenses, reducing peripheral and neuroinflammation, and protecting neurons. Our findings provide valuable data and a theoretical foundation for the potential therapeutic application of XNX in AD treatment and its further development.

TMF Attenuates Cognitive Impairment and Neuroinflammation by Inhibiting the MAPK/NF-κB Pathway in Alzheimer's Disease: A Multi-Omics Analysis

The rising prevalence of Alzheimer's disease (AD) underscores the urgent need for novel therapeutic agents derived from natural sources. Among flavonoids, 3',4',5,7-tetramethoxyflavone (TMF), a structural analog of luteolin, has gained attention for its favorable pharmacokinetics and potential neuroprotective properties. Despite the significant neuroprotective effects and favorable pharmacokinetics of TMF, its efficacy and mechanism of action in AD remain unclear. This study explored TMF's pharmacological effects in AD models, highlighting its ability to improve memory and cognitive deficits in APP/PS1 mice. TMF reduced Aβ plaques, NFTs formation, and glial activation while suppressing neuroinflammation through the MAPK/NF-κB pathway. Further analysis in LPS-induced BV2 cells revealed TMF's ability to reduce microglial activation. These findings highlight the anti-neuroinflammatory activity of TMF, suggesting its potential as a treatment for AD.

Network pharmacology and experimental verification to investigate the mechanism of isoliquiritigenin for the treatment of Alzheimer's disease

Isoliquiritigenin (ISL), a flavone isolated from licorice, has been demonstrated to exhibit anti-inflammatory and antioxidant properties in the treatment of Alzheimer's disease (AD). However, the molecular details of the contribution of ISL to AD remain largely elusive. The present study aimed to investigate the molecular mechanisms of ISL against AD. In this study, AD targets and ISL targets were collected via different databases. The overlapped targets between AD and ISL were generated with Venny. Then we performed Gene Ontology (GO) and Kyoto Encyclopaedia of Genes and Genomes (KEGG) pathway enrichment analyses on these common targets. The protein-protein interaction (PPI) network was constructed and clusters were obtained using the Molecular Complex Detection (MCODE) and the Cytohubba plugins. Further, molecular docking study was performed for these core targets. Subsequently, the receiver operating characteristic (ROC) curve analysis and the assessment of hub gene expression levels between AD and healthy individuals were used to estimate a possible link between target genes in AD. Finally, experiments were conducted to verify the therapeutic mechanism of ISL in lipopolysaccharide (LPS)-induced BV2 microglial cells. GO and KEGG pathway analysis found that ISL was significantly enriched in regulation of mitogen-activated protein kinase (MAPK) signaling pathway. The PPI network manifested 7 key targets including albumin (ALB), epidermal growth factor receptor (EGFR), solute carrier family 2 member 1 (SLC2A1), insulin-like growth factor 1 (IGF1), mitogen-activated protein kinase 1 (MAPK1), peroxisome proliferator activated receptor alpha (PPARA) and peroxisome proliferator activated receptor gamma (PPAR-γ, PPARG). Molecular docking showed that ISL had high binding affinity with these key targets. The experimental results revealed that ISL decreased extracellular signal-regulated kinase 1/2 (ERK1/2) phosphorylation and increased the expression of PPAR-γ, and suppressed the production of proinflammatory mediators. Our work revealed that ISL might be an effective treatment strategy in the treatment of AD by its anti-inflammatory effect towards microglia through the ERK/PPAR-γ pathway.