Pathogenesis of Alzheimer's Disease

Glycolytic dysregulation in Alzheimer's disease: unveiling new avenues for understanding pathogenesis and improving therapy

Alzheimer's disease poses a significant global health challenge owing to the progressive cognitive decline of patients and absence of curative treatments. The current therapeutic strategies, primarily based on cholinesterase inhibitors and N-methyl-D-aspartate receptor antagonists, offer limited symptomatic relief without halting disease progression, highlighting an urgent need for novel research directions that address the key mechanisms underlying Alzheimer's disease. Recent studies have provided insights into the critical role of glycolysis, a fundamental energy metabolism pathway in the brain, in the pathogenesis of Alzheimer's disease. Alterations in glycolytic processes within neurons and glial cells, including microglia, astrocytes, and oligodendrocytes, have been identified as significant contributors to the pathological landscape of Alzheimer's disease. Glycolytic changes impact neuronal health and function, thus offering promising targets for therapeutic intervention. The purpose of this review is to consolidate current knowledge on the modifications in glycolysis associated with Alzheimer's disease and explore the mechanisms by which these abnormalities contribute to disease onset and progression. Comprehensive focus on the pathways through which glycolytic dysfunction influences Alzheimer's disease pathology should provide insights into potential therapeutic targets and strategies that pave the way for groundbreaking treatments, emphasizing the importance of understanding metabolic processes in the quest for clarification and management of Alzheimer's disease.

Mining and analysis of adverse events associated with aducanumab: a real-world study using FDA Adverse Event Reporting System database

BACKGROUND

Aducanumab, a monoclonal antibody, received approval for the treatment of Alzheimer's disease in 2021. However, it remains controversial over the security of this drug. In this study, aducanumab-related adverse events (AEs) were evaluated through data mining based on the FDA Adverse Event Reporting System (FAERS) database.

RESEARCH DESIGN AND METHODS

The AE reports induced by aducanumab as the primary suspected drug were extracted from the FAERS database. The clinical characteristics of aducanumab-associated reports were analyzed. The potential new AE signals of aducanumab were explored using four disproportionality analysis methods. Furthermore, the difference in aducanumab-associated AE signals was investigated concerning sex, age, weight, dose, onset time, and continent.

RESULTS

In total, 328 reports and 793 AEs associated with aducanumab were identified. Six new AEs were identified. No significant sex and weight difference in aducanumab-related signals was found. Notably, nervous system disorders, especially 'amyloid related imaging abnormality-edema/effusion' and 'amyloid related imaging abnormality-microhaemorrhages and haemosiderin deposits,' were more frequently to be reported within 121-240 days, particularly in Europe.

CONCLUSIONS

This study contributes real-world evidence regarding the safety of aducanumab.

Systematic review and meta-analysis of repetitive transcranial magnetic stimulation (rTMS) for activities of daily living in Alzheimer's disease

OBJECTIVE

This systematic review of randomised controlled trials (RCTs) was conducted to assess the effect of repetitive transcranial magnetic stimulation (rTMS) on activities of daily living (ADLs) in Alzheimer's disease (AD) patients.

DATA SOURCES

Ten databases were retrieved for pertinent Chinese and English literatures published up until January 2024.

REVIEW METHODS

All RCTs of rTMS for ADLs in AD were included in this meta-analysis. Two researchers independently selected the literatures, retrieved the data of included literatures, accessed risk-of-bias of literatures with the Cochrane Collaboration's quality criteria and then cross-checked. Meta-analysis was carried out with Cochrane's Review Manager (RevMan, version 5.4). The PRISMA guidelines were followed in this systematic review.

RESULTS

The 37 literatures involving 2461 patients with AD were included in this study. Compared with the control groups received the interventions such as routine pharmacotherapy, cognitive training, ect., with/without sham-rTMS, the experiment groups received the interventions of the control groups and rTMS. The findings were as follows: ADL scale [mean difference (MD) = -3.92, 95%CI (-4.93, -2.91), P < 0.00001]; Barthel Index (BI) [MD = 9.75, 95% CI (6.66, 12.85), P < 0.00001]; Modified Barthel Index (MBI) [MD = 5.43, 95% CI (3.13, 7.73), P < 0.00001]. The differences were statistically significant for all indicators. In 29 studies, rTMS stimulation sites were located in the dorsolateral prefrontal cortex (DLPFC).

CONCLUSION

The rTMS could improve the ADLs in AD patients, and the DLPFC was a frequently used stimulation site of the rTMS for AD treatment.

Novel techniques for early diagnosis and monitoring of Alzheimer's disease

INTRODUCTION

Alzheimer's disease (AD) is the most common neurodegenerative disorder, which is characterized by a progressive loss of cognitive functions. The high prevalence, chronicity, and multimorbidity are very common in AD, which significantly impair the quality of life and functioning of patients. Early detection and accurate diagnosis of Alzheimer's disease (AD) can stop the illness from progressing thereby postponing its symptoms. Therefore, for the early diagnosis and monitoring of AD, more sensitive, noninvasive, straightforward, and affordable screening tools are needed.

AREAS COVERED

This review summarizes the importance of early detection methods and novel techniques for Alzheimer's disease diagnosis that can be used by healthcare professionals.

EXPERT OPINION

Early diagnosis assists the patient and caregivers to understand the problem establishing reasonable goals and making future plans together. Early diagnosis techniques not only help in monitoring disease progression but also provide crucial information for the development of novel therapeutic targets. Researchers can plan to potentially alleviate symptoms or slow down the progression of Alzheimer's disease by identifying early molecular changes and targeting altered pathways.

Increased GABBR2 Expression on Cell Membranes Causes Increased Ca2 + Inward Flow, Associated with Cognitive Impairment in Early Alzheimer's Disease

Alzheimer's disease (AD) and mild cognitive impairment (MCI) are a serious global public health problem. The aim of this study was to analyze the key molecular pathological mechanisms that occur in early AD progression as well as MCI. Expression profiling data from brain homogenates of 8 normal volunteers, and 6 patients with prodromal AD who had developed MCI were analyzed, and the data were obtained from GSE12685. Further, overexpression of GABBR2 was achieved in human neuroblastoma cell lines SH-SY5Y and BE(2)-M17 using expression plasmid transfection. GABBR2 was significantly overexpressed in brain tissues of patients with prodromal AD who had developed MCI, as compared to normal brains. Moreover, GABBR2 overexpressing cells showed a significant increase in intracellular Ca2+ concentration, a large amount of reactive oxygen species production, a large opening of the mitochondrial permeability transition pore and a significant increase in apoptosis compared with control cells. GABBR2 overexpression was significantly involved in early AD progression and MCI by causing cellular events such as intracellular Ca2+ imbalance, oxidative stress, and mitochondrial dysfunction.

Cerebral ischemic injury impairs autophagy and exacerbates cognitive impairment in APP/PS1 mice

Autophagy plays a pivotal role in the pathogenesis and progression of Alzheimer's disease (AD). Oxidative stress and neuroinflammation involved in autophagy are associated with the cerebral ischemia-induced exacerbation of cognitive deficits in individuals with AD. APP/PS1 mice underwent bilateral common carotid artery clamping for 15 min. The degrees of Aβ deposition, oxidative stress, neuroinflammation, and neuronal and synaptic loss after cerebral ischemia were detected. Autophagy levels were assessed by RT-qPCR, western blotting, immunofluorescence staining, and transmission electron microscopy. DPEs occurring in the hippocampus of APP/PS1 mice after cerebral ischemia were analyzed via label-free proteomics. The present study demonstrated that cerebral ischemia exacerbates learning and memory deficits in APP/PS1 mice. Cerebral ischemia aggravated the cognitive impairment in APP/PS1 mice by worsening neuronal and synaptic loss through damage to intracellular autophagy, increased oxidative stress, and neuroinflammation. Notably, cerebral ischemia interfered with mitochondrial and nuclear transport functions in APP/PS1 transgenic mice, thereby aggravating cognitive deficits. Cellular transport functions may be a target for preventing AD progression. In summary, autophagy is impaired in APP/PS1 mice compared with WT mice, and oxidative stress and neuroinflammation caused by cerebral ischemia exacerbate autophagy-induced damage and are responsible for cognitive decline. Label-free proteomics indicated that cerebral ischemia results in abnormal Abcb8, Sestd1, TPR, and Rab8a protein expression in the hippocampus of APP/PS1 transgenic mice and that an imbalance of mitochondrial transport and nuclear transport functions exacerbates cognitive deficits. Improving autophagy and restoring organelle transport may be targets for the prevention and treatment of dementia.

Diffusion Tensor Imaging Analysis Along the Perivascular Space (DTI-ALPS) Demonstrates That Sleep Disorders Exacerbate Glymphatic Circulatory Impairment and Cognitive Impairment in Patients with Alzheimer's Disease

Objective

Sleep disorders are common in Alzheimer's disease (AD) patients and can impair the glymphatic system, leading to cognitive decline. This study aimed to investigate whether AD patients with sleep disorders exhibit worse glymphatic function and more severe cognitive impairment compared to those without sleep disorders and to explore the underlying molecular imaging mechanisms.

Methods

This study included 40 AD patients with sleep disorders (ADSD), 39 cognitively matched AD patients without sleep disorders (ADNSD), and 25 healthy middle-aged and elderly controls (NC). Participants underwent functional magnetic resonance imaging (fMRI), and cognitive and sleep assessments. The ALPS (Along the Perivascular Space) index was calculated, followed by intergroup comparisons, correlation analyses, and mediation analyses. The diagnostic utility of the ALPS index was assessed using a receiver operating characteristic (ROC) curve.

Results

The ALPS index was lower in the ADNSD and ADSD groups compared to the NC group. In the ADSD group, PSQI scores were negatively correlated with MMSE scores. The ALPS index was positively correlated with MMSE scores and negatively with PSQI scores. Mediation analyses indicated that the ALPS index partially mediated the effect of sleep disturbances on cognitive impairment (indirect effect = -0.134; mediation effect = 30.505%). The area under the ROC curve (AUROC) for distinguishing ADSD from ADNSD was 0.86, with a cutoff ALPS index value 1.309.

Conclusion

Sleep disorders worsen glymphatic function and cognitive impairment in AD patients. The ALPS index partially mediates the impact of sleep disorders on cognitive function and shows moderate accuracy in distinguishing between patients with ADSD and ADNSD.

Egln3 expression in microglia enhances the neuroinflammatory responses in Alzheimer's disease

Alzheimer's disease (AD), characterized by cognitive and behavioral abnormalities, is the most prevalent neurodegenerative disease worldwide. Neuroinflammation, which is induced by microglial activation, resulting in the expression of a multitude of inflammatory factors, is one of the principal characteristics of AD. Herein, we found that Egln3 is differentially expressed in microglia in the brains of AD mice. Egln3 is a member of the Egln family of proline hydroxylases, which regulates a variety of biological processes, including transcription, the cell cycle, and apoptosis, through hydroxylation, ubiquitylation, and participation in glycolysis. To further observe the effects of Egln3 on cognitive function, we utilized APP/PS1 mice as a pathological model of AD to conduct behavioral experiments and assess the expression levels of Aβ and inflammatory factors. The specific mechanisms by which Egln3 affects microglial activation were analyzed using in vitro experiments and transcriptome sequencing. The results of these analyses demonstrated that Egln3 is highly expressed in microglia in AD. Inhibition of Egln3 expression in the brains of APP/PS1 mice improves neuroinflammatory responses and cognitive function, indicating that a high expression of Egln3 promotes AD progression. Furthermore, our findings indicate that Egln3 could activate the MAPK pathway, which in turn contributes to the aggravation of neuroinflammation. Inhibition of the MAPK pathway results in attenuation of the pro-inflammatory state of microglia. Consequently, Egln3 may exacerbate neuroinflammation and promote AD progression via the MAPK pathway in microglia, making it a promising target for AD-related therapies.

Causal relationships between Alzheimer's disease and metabolic dysfunction associated with fatty liver disease: insights from bidirectional network Mendelian Randomization analysis

INTRODUCTION/OBJECTIVES

Several observational investigations have observed the possible links between Alzheimer's disease (AD) and metabolic dysfunction associated with fatty liver disease (MAFLD), yet the underlying causal relationships remain undetermined. This study aimed to systemically infer the causal associations between AD and MAFLD by employing a bidirectional network two-sample Mendelian randomization (MR) analysis.

METHODS

Genome-wide significant (P < 5 × 10- 8) genetic variants associated with AD and MAFLD were selected as instrumental variables (IVs) from the consortium of FinnGen, MRC-IEU, UK biobank, and genome-wide association studies (GWAS), respectively. The study sample sizes range from 55,134 to 423,738 for AD and from 218,792 to 778,614 for MAFLD. In the forward analysis, AD was set as the exposure factor, and MAFLD was employed as the disease outcome. Causal relationships between AD and MAFLD were evaluated using inverse-variance weighted (IVW), MR Egger regression, the weighted median, and weighted mode. Additionally, the reverse MR analysis was conducted to infer causality between MAFLD and AD. Sensitivity analyses were performed to assess the robustness of causal estimates.

RESULTS

In the forward MR analysis, the genetically determined family history of AD was associated with a lower risk of MAFLD (mother's history: ORdiscovery=0.08, 95%CI: 0.03, 0.22, P = 7.91 × 10- 7; ORreplicate=0.83, 95%CI: 0.74, 0.94, P = 3.68 × 10- 3; father's history: ORdiscovery=0.01, 95%CI: 0.01, 0.08, P = 5.48 × 10- 5; ORreplicate=0.79, 95%CI: 0.68, 0.93, P = 4.07 × 10- 3; family history: ORdiscovery=0.84, 95%CI: 0.77, 0.91, P = 6.30 × 10- 5; ORreplicate=0.15, 95%CI: 0.05, 0.41, P = 2.51 × 10- 4) in the primary MAFLD cohort. Consistent findings were observed in an independent MAFLD cohort (all P < 0.05). However, the reverse MR analysis suggested that genetic susceptibility to MAFLD had no causal effects on developing AD.

CONCLUSION

Our study demonstrates a causal association between a family history of AD and a lower risk of MAFLD. It suggests that individuals with a history of AD may benefit from tailored metabolic assessments to better understand their risk of MAFLD, and inform the development of preventive strategies targeting high-risk populations.

Gut microbiota dysbiosis in Alzheimer's disease (AD): Insights from human clinical studies and the mouse AD models

Alzheimer's Disease (AD) is a debilitating neurocognitive disorder with an unclear underlying mechanism. Recent studies have implicated gut microbiota dysbiosis with the onset and progression of AD. The connection between gut microbiota and AD can significantly affect the prevention and treatment of AD patients. This systematic review summarizes primary outcomes of human and mouse AD models concerning gut microbiota alterations. A systematic literature search in February through March 2023 was conducted on PubMed, Embase, and Web of Science. We identified 711 as potential manuscripts of which 672 were excluded because of irrelevance to the identified search criteria. Primary outcomes include microbiota compositions of control and AD models in humans and mice. In total, 39 studies were included (19 mouse and 20 human studies), published between 2017 and 2023. We included studies involving well-established mice models of AD (5xFAD, 3xTg-AD, APP/PS1, Tg2576, and APPPS2) which harbor mutations and genes that drive the formation of Aß plaques. All human studies were included on those with AD or mild cognitive impairment. Among alterations in gut microbiota, most studies found a decreased abundance of the phyla Firmicutes and Bifidobacteria, a genus of the phylum Actinomycetota. An increased abundance of the phyla Bacteroidetes and Proteobacteria were identified in animal and human studies. Studies indicated that gut microbiota alter the pathogenesis of AD through its impact on neuroinflammation and permeability of the gastrointestinal tract. The ensuing increase in blood-brain barrier permeability may accelerate Aβ penetrance and formation of neuritic plaques that align with the amyloid hypothesis of AD pathogenesis. Further studies should assess the relationship between gut microbiota and AD progression and therapy preserving beneficial gut microbiota.

Network Pharmacology, Molecular Docking, and In Vitro Insights into the Potential of Mitragyna speciosa for Alzheimer's Disease

Mitragyna speciosa Korth. Havil (MS) has a traditional use in relieving pain, managing hypertension, treating cough, and diarrhea, and as a morphine substitute in addiction recovery. Its potential in addressing Alzheimer's disease (AD), a neurodegenerative condition with no effective treatments, is under investigation. This study aims to explore MS mechanisms in treating AD through network pharmacology, molecular docking, and in vitro studies. Using network pharmacology, we identified 19 MS components that may affect 60 AD-related targets. The compound-target network highlighted significant interactions among 60 nodes and 470 edges, with an average node degree of 15.7. The KEGG enrichment analysis revealed Alzheimer's disease (hsa05010) as a relevant pathway. We connected 20 targets to tau and β-amyloid proteins through gene expression data from the AlzData database. Docking studies demonstrated high binding affinities of MS compounds like acetylursolic acid, beta-sitosterol, isomitraphylline, and speciophylline to AD-related proteins, such as AKT1, GSK3B, NFκB1, and BACE1. In vitro studies showed that ethanolic (EE), distilled water (DWE), and pressurized hot water (PHWE) extracts of MS-treated 100 μM H2O2-induced SH-SY5Y cells significantly reduced oxidative damage. This research underscores the multi-component, multi-target, and multi-pathway effects of MS on AD, providing insights for future research and potential clinical applications.

Silent Information Regulator 1/Peroxisome Proliferator-Activated Receptor-γ Coactivator-1α Axis: A Promising Target for Parkinson's and Alzheimer's Disease Therapies

One of the key challenges in medical research is developing safe medications to treat neurodegenerative disorders. Increased oxidative stress, mitochondrial dysfunction, and neuroinflammation are common features of Alzheimer's disease (AD) and Parkinson's disease (PD). Silent information regulator 1 (SIRT-1), part of the sirtuin family, plays a critical role in various physiological processes by binding to histones and nonhistone proteins. SIRT-1 primarily mitigates oxidative stress and regulates mitochondrial activity by maintaining the deacetylated form of peroxisome proliferator-activated receptor-γ coactivator-1α (PGC-1α), ensuring stable PGC-1α levels. Research has shown reduced SIRT-1/PGC-1α expression in AD and PD models. Targeting this pathway presents a promising therapeutic approach for managing AD and PD, potentially leading to disease-modifying treatments and improved outcomes. This review highlights the findings of various studies suggesting that the SIRT-1/PGC-1α pathway promotes mitochondrial biogenesis, synaptic plasticity, and cognitive function, as well as exerts antioxidant, anti-inflammatory, and anti-apoptotic effects, offering a potential method for AD and PD treatment.

Ginsenoside Rg2 alleviates astrocyte inflammation and ameliorates the permeability of the Alzheimer's disease related blood-brain barrier

BACKGROUND

Damage to the blood-brain barrier (BBB) is vital for the development of Alzheimer's disease (AD). Ginsenoside Rg2 (G-Rg2) has been shown to improve a variety of brain injuries, but whether G-Rg2 can improve the BBB leakage related to AD is still unclear.

PURPOSE

Illuminate the effect and mechanism of G-Rg2 on AD-related BBB damage. To clarify the role of G-Rg2 in Toll-like receptor pathway and oxidative stress pathway and its effect on tight junction proteins (TJs) expression in vivo and in vitro experiments.

METHODS AND RESULTS

In our research, the tightness of the BBB was improved and the inflammatory pathway was suppressed after 4 weeks of treatment with G-Rg2 (10 mg kg-1 and 20 mg kg-1) in aluminum trichloride (AlCl3) plus d-galactose (D-gal) caused AD mice (p < 0.05; p < 0.01). Concurrently, the stability of TJs in mouse brain endothelial cells (bEnd3) was improved after okadaic acid (OA) -induced AD model cells were pretreated with G-Rg2 (5 μM, 10 μM, and 20 μM) for 24 h (p < 0.05; p < 0.01). The oxidative stress pathway and Toll-like receptor pathway in mouse astrocyte-cerebellum (MA-c) were inhibited (p < 0.05; p < 0.01). Meanwhile, in vitro interaction model results showed that G-Rg2 reduced the activation of MA-c, thereby alleviating the degradation of TJs in bEnd3 (p < 0.05; p < 0.01). The co-culture system of MA-c and bEnd3 further clearly demonstrated that G-Rg2 (20 μM) could improve their interaction and enhance BBB tightness.

CONCLUSION

This study suggests that G-Rg2 can inhibit the TLR4/MyD88/MMP9 inflammatory pathway by reducing the activation of MA-c and the binding of TLR4 to MyD88, thereby decreasing the secretion of inflammatory factors and matrix metalloproteinases (MMPs), hence maintaining the stability of TJs in bEnd3, which may be one of the mechanisms of G-Rg2 in reducing AD-related BBB damage.

Research progress of metalloporphyrin against neurodegen-erative diseases

Neurodegenerative disorders are a group of diseases caused by the degeneration and apoptosis of neurons in the brain and spinal cord, which seriously affect human ability of motion perception, memory and cognition. Peroxynitrite can cause oxidative damage in the brain exhibiting neurotoxicity, and its excussive accumulation is closely related to neurodegenerative diseases. Therefore, effectively scavenging peroxynitrite may become a therapeutic strategy for neurodegenerative diseases. Due to their high peroxynitrite scavenging ability, some water-soluble metalloporphyrins have recently attracted much attention. Metalloporphyrins such as iron porphyrins and manganese porphyrins have certain neuroprotective effects, including inhibiting amyloid plaque accumulation, alleviating oxidative stress and neuroinflammatory damage, improving mitochondrial function and reducing neuronal apoptosis. However, there are certain limitations for metalloporphyrins as neuroprotective drugs, and some metal porphyrins have poor blood-brain barrier penetration. To overcome the obstacle, in addition to traditional synthesis processes, metalloporphyrins can also be prepared into nanoparticles to improve bioavailability in vivo. Here, we will review the mechanisms underlying the neuroprotective effects of metalloporphyrin and explore its therapeutic potential for neurodegenerative disorders.

Effects and mechanisms of APP and its cleavage product Aβ in the comorbidity of sarcopenia and Alzheimer's disease

Sarcopenia and AD are both classic degenerative diseases, and there is growing epidemiological evidence of their comorbidity with aging; however, the mechanisms underlying the biology of their commonality have not yet been thoroughly investigated. APP is a membrane protein that is expressed in tissues and is expressed not only in the nervous system but also in the NMJ and muscle. Deposition of its proteolytic cleavage product, Aβ, has been described as a central component of AD pathogenesis. Recent studies have shown that excessive accumulation and aberrant expression of APP in muscle lead to pathological muscle lesions, but the pathogenic mechanism by which APP and its proteolytic cleavage products act in skeletal muscle is less well understood. By summarizing and analyzing the literature concerning the role, pathogenicity and pathological mechanisms of APP and its cleavage products in the nervous system and muscles, we aimed to explore the intrinsic pathological mechanisms of myocerebral comorbidities and to provide new perspectives and theoretical foundations for the prevention and treatment of AD and sarcopenia comorbidities.

The role of ferritinophagy and ferroptosis in Alzheimer's disease

Iron is a crucial mineral element within human cells, serving as a pivotal cofactor for diverse biological enzymes. Ferritin plays a crucial role in maintaining iron homeostasis within the body through its ability to sequester and release iron. Ferritinophagy is a selective autophagic process in cells that specifically facilitates the degradation of ferritin and subsequent release of free iron, thereby regulating intracellular iron homeostasis. The nuclear receptor coactivator 4 (NCOA4) serves as a pivotal regulator in the entire process of ferritinophagy, facilitating its binding to ferritin and subsequent delivering to lysosomes for degradation, thereby enabling the release of free iron. The free iron ions within the cell undergo catalysis through the Fenton reaction, resulting in a substantial generation of reactive oxygen species (ROS). This process induces lipid peroxidation, thereby stimulating a cascade leading to cellular tissue damage and subsequent initiation of ferroptosis. Alzheimer's disease (AD) is a neurodegenerative disorder characterized by progressive deterioration of emotional memory and cognitive function, accompanied by mental and behavioral aberrations. The pathology of the disease is characterized by aberrant deposition of amyloid β-protein (Aβ) and hyperphosphorylated tau protein. It has been observed that evident iron metabolism disorders and accumulation of lipid peroxides occur in AD, indicating a significant impact of ferritinophagy and ferroptosis on the pathogenesis and progression of AD. This article elucidates the process and mechanism of ferritinophagy and ferroptosis, investigating their implications in AD to identify novel targets for therapeutic intervention.

Dexmedetomidine Attenuated Neuron Death, Cognitive Decline, and Anxiety-Like Behavior by Inhibiting CXCL2 in CA1 Region of AD Mice

Purpose

β-amyloid overload-induced neuroinflammation and neuronal loss are key pathological changes that occur during the progression of Alzheimer's disease (AD). Dexmedetomidine (Dex) exhibits neuroprotective and anti-inflammatory effects on the nervous system. However, the effect of Dex in AD mice remains unclear, and its neuroprotective regulatory mechanism requires further investigation. This study aimed to reveal how Dex protects against Aβ induced neuropathological changes and behavior dysfunction in AD mice.

Methods

An AD mouse model was established by the injection of Aβ into the brains of mice, followed by intraperitoneal injection with Dex. CXCL2 overexpression and Yohimbine, a Dex inhibitor, were used to investigate the role of Dex and CXCL2 in the regulation of neuronal loss, cognitive decline, and anxiety-like behavior in AD mice. Behavioral tests were performed to evaluate the cognitive and anxiety status of the mice. Nissl staining and immunofluorescence experiments were conducted to evaluate the status of the hippocampal neurons and astrocytes. qRT-PCR was performed to detect the expression of CXCL2, IL-1β, INOS, SPHK1, Bcl2, IFN-γ, and Caspase 1. The malondialdehyde (MDA) level was detected using an ELISA kit. Terminal TUNEL and Fluoro-Jade C (FJC) staining were used to measure the cell apoptosis rate.

Results

In AD mice, cognitive decline and anxiety-like behaviors were significantly improved by the Dex treatment. The number of neurons was increased in mice in the Dex + AD group compared to those in the AD group, and the number of astrocytes was not significantly different between the two groups. CXCL2, IL-1β, iNOS, and SPHK1 levels were significantly lower in Dex-treated AD mice than those in AD mice. Overloading of CXCL2 or Yohimbine reversed the protective effect of Dex on neuron number and cognitive and anxiety symptoms in AD mice.

Conclusion

Our results suggest that Dex exerts neuroprotective effects by downregulating CXCL2. Dex shows potential as a therapeutic drug for AD.

Effects of electroacupuncture on microglia phenotype and epigenetic modulation of C/EBPβ in SAMP8 mice

BACKGROUND

Alzheimer's disease (AD), an age-progressive neurodegenerative disease, is featured by a relentless deterioration of cognitive abilities. In parallel with the hypotheses of Aβ and tau, microglia-mediated neuroinflammation is a core pathological hallmark of AD. Promoting the transition of microglia from M1 to M2 phenotype and inhibition of neuroinflammatory response provide new insights into the treatment of AD. And substantial studies have confirmed that overexpression of C/EBPβ accelerates the progression of AD pathology. Acupuncture is renowned for its unique advantages including safety and effectiveness, which has gained wide application in geriatric diseases, and thoroughly exploring the mechanism for its treatment of AD will provide scientific basis for its clinical application.

METHODS

In this study, SAMP8 mice were employed and EA therapy was performed as the main intervention. The combination of behavioural experiments (including water maze and novel objective recognition), Immunofluorescence, Western blot, and Chip-qPCR assay were performed to compare between different groups.

RESULTS

EA therapy facilitates the polarization of microglia from M1 to M2 phenotype, reduces pro-inflammatory cytokines (IL-6, IL-1β and TNF-α) and promotes the expression of anti-inflammatory factors (IL-4 and IL-10), as well as attenuates neuroinflammation. Simultaneously, EA also inhibits the enrichment of H3K9ac at C/EBPβ promoter region and expression of C/EBPβ. Thus, it was evident that EA had a favorable effect on ameliorating cognitive decline in SAMP8 mice.

CONCLUSION

EA therapy may ameliorate cognitive deficits in AD via facilitating microglia shift from M1 to M2 phenotype and epigenetically regulating C/EBPβ. And further studies are required to better understand how the mechanism between microglia and epigenetic modulation of C/EBPβ are effective in reversing AD.

Nrf2 pathways in neuroprotection: Alleviating mitochondrial dysfunction and cognitive impairment in aging

Mitochondrial dysfunction and cognitive impairment are widespread phenomena among the elderly, being crucial factors that contribute to neurodegenerative diseases. Nuclear factor erythroid 2-related factor 2 (Nrf2) is an important regulator of cellular defense systems, including that against oxidative stress. As such, increased Nrf2 activity may serve as a strategy to avert mitochondrial dysfunction and cognitive decline. Scientific data on Nrf2-mediated neuroprotection was collected from PubMed, Google Scholar, and Science Direct, specifically addressing mitochondrial dysfunction and cognitive impairment in older people. Search terms included "Nrf2", "mitochondrial dysfunction," "cognitive impairment," and "neuroprotection." Studies focusing on in vitro and in vivo models and clinical investigations were included to review Nrf2's therapeutic potential comprehensively. The relative studies have demonstrated that increased Nrf2 activity could improve mitochondrial performance, decrease oxidative pressure, and mitigate cognitive impairment. To a large extent, this is achieved through the modulation of critical cellular signalling pathways such as the Keap1/Nrf2 pathway, mitochondrial biogenesis, and neuroinflammatory responses. The present review summarizes the recent progress in comprehending the molecular mechanisms regarding the neuroprotective benefits mediated by Nrf2 through its substantial role against mitochondrial dysfunction and cognitive impairment. This review also emphasizes Nrf2-target pathways and their contribution to cognitive function improvement and rescue from mitochondria-related abnormalities as treatment strategies for neurodegenerative diseases that often affect elderly individuals.

Implications of liquid-liquid phase separation and ferroptosis in Alzheimer's disease

Neuronal cell demise represents a prevalent occurrence throughout the advancement of Alzheimer's disease (AD). However, the mechanism of triggering the death of neuronal cells remains unclear. Its potential mechanisms include aggregation of soluble amyloid-beta (Aβ) to form insoluble amyloid plaques, abnormal phosphorylation of tau protein and formation of intracellular neurofibrillary tangles (NFTs), neuroinflammation, ferroptosis, oxidative stress, liquid-liquid phase separation (LLPS) and metal ion disorders. Among them, ferroptosis is an iron-dependent lipid peroxidation-driven cell death and emerging evidences have demonstrated the involvement of ferroptosis in the pathological process of AD. The sensitivity to ferroptosis is tightly linked to numerous biological processes. Moreover, emerging evidences indicate that LLPS has great impacts on regulating human health and diseases, especially AD. Soluble Aβ can undergo LLPS to form liquid-like droplets, which can lead to the formation of insoluble amyloid plaques. Meanwhile, tau has a high propensity to condensate via the mechanism of LLPS, which can lead to the formation of NFTs. In this review, we summarize the most recent advancements pertaining to LLPS and ferroptosis in AD. Our primary focus is on expounding the influence of Aβ, tau protein, iron ions, and lipid oxidation on the intricate mechanisms underlying ferroptosis and LLPS within the domain of AD pathology. Additionally, we delve into the intricate cross-interactions that occur between LLPS and ferroptosis in the context of AD. Our findings are expected to serve as a theoretical and experimental foundation for clinical research and targeted therapy for AD.

Advances of curcumin in nervous system diseases: the effect of regulating oxidative stress and clinical studies

In recent years, researchers have highly observed that neurological disorders (NSDs) with the aging of the population are a global health burden whose prevalence is increasing every year. Previous evidence suggested that the occurrence of neurological disorders is correlated with predisposing factors such as inflammation, aging, and injury. Particularly, the neuronal cells are susceptible to oxidative stress, leading to lesions caused by high oxygen-consuming properties. Oxidative stress (OS) is a state of peroxidation, which occurs as a result of the disruption of the balance between oxidizing and antioxidizing substances. The oxidative intermediates such as free radicals, hydrogen peroxide (H2O2), and superoxide anion (O2-) produced by OS promote disease progression. Curcumin, a natural diketone derived from turmeric, is a natural antioxidant with a wide range of neuroprotective, anti-inflammatory, anti-tumor, anti-aging, and antioxidant effects. Fortunately, curcumin is recognized for its potent antioxidant properties and is considered a promising candidate for the prevention and treatment of neurological diseases. Consequently, this review elucidates the mechanisms by which curcumin mitigates oxidative stress and emphasizes the potential in treating nervous system disorders, including depression, Alzheimer's disease, Parkinson's disease, epilepsy, subarachnoid hemorrhage, and glioblastoma. We aim to provide a new therapeutic option for the management of neurological diseases.

GHRH and its analogues in central nervous system diseases

Growth hormone-releasing hormone (GHRH) is primarily produced by the hypothalamus and stimulates the release of growth hormone (GH) in the anterior pituitary gland, which subsequently regulates the production of hepatic insulin-like growth factor-1 (IGF-1). GH and IGF-1 have potent effects on promoting cell proliferation, inhibiting cell apoptosis, as well as regulating cell metabolism. In central nerve system (CNS), GHRH/GH/IGF-1 promote brain development and growth, stimulate neuronal proliferation, and regulate neurotransmitter release, thereby participating in the regulation of various CNS physiological activities. In addition to hypothalamus-pituitary gland, GHRH and GHRH receptor (GHRH-R) are also expressed in other brain cells or tissues, such as endogenous neural stem cells (NSCs) and tumor cells. Alternations in GHRH/GH/IGF-1 axis are associated with various CNS diseases, for example, Alzheimer's disease, amyotrophic lateral sclerosis and emotional disorders manifest GHRH, GH or IGF-1 deficiency, and GH or IGF-1 supplementation exerts beneficial therapeutic effects on these diseases. CNS tumors, such as glioma, can express GHRH and GHRH-R, and activating this signaling pathway promotes tumor cell growth. The synthesized GHRH antagonists have shown to inhibit glioma cell growth and may hold promising as an adjuvant therapy for treating glioma. In addition, we have shown that GHRH agonist MR-409 can improve neurological sequelae after ischemic stroke by activating extrapituitary GHRH-R signaling and promoting endogenous NSCs-derived neuronal regeneration. This article reviews the involvement of GHRH/GH/IGF-1 in CNS diseases, and potential roles of GHRH agonists and antagonists in treating CNS diseases.

The Role of Non-Coding RNAs in Mitochondrial Dysfunction of Alzheimer's Disease

Although brain amyloid-β (Aβ) peptide buildup is the main cause of Alzheimer's disease (AD), mitochondrial abnormalities can also contribute to the illness's development, as either a primary or secondary factor, as programmed cell death and efficient energy generation depend on the proper operation of mitochondria. As a result, non-coding RNAs (ncRNAs) may play a crucial role in ensuring that nuclear genes related to mitochondria and mitochondrial genes function normally. Interestingly, a significant number of recent studies have focused on the impact of ncRNAs on the expression of nucleus and mitochondrial genes. Additionally, researchers have proposed some intriguing therapeutic approaches to treat and reduce the severity of AD by adjusting the levels of these ncRNAs. The goal of this work was to consolidate the existing knowledge in this field of study by systematically investigating ncRNAs, with a particular emphasis on microRNAs (miRNAs), long non-coding RNAs (lncRNAs), circular RNAs (circRNAs), and small nucleolar RNAs (snoRNAs). Therefore, the impact and processes by which ncRNAs govern mitochondrial activity in the onset and progression of AD are thoroughly reviewed in this article. Collectively, the effects of ncRNAs on physiological and molecular mechanisms associated with mitochondrial abnormalities that exacerbate AD are thoroughly reviewed in the current research, while also emphasizing the relationship between disturbed mitophagy in AD and ncRNAs.

Licochalcone A Ameliorates Cognitive Dysfunction in an Alzheimer's Disease Model by Inhibiting Endoplasmic Reticulum Stress-Mediated Apoptosis

BACKGROUND

Endoplasmic reticulum (ER) stress-induced neurodegeneration has been considered an underlying cause of Alzheimer disease (AD). Here, we investigated the beneficial effects of licochalcone A (Lico A), a valuable flavonoid of the root of the Glycyrrhiza species, against cognitive impairment in AD by regulating ER stress.

METHODS

The triple transgenic mouse AD models were used and were administrated 5 or 15 mg/kg Lico A. Cognitive deficits, Aβ deposition, ER stress, and neuronal apoptosis were determined using Morris Water Maze test, probe trial, immunofluorescence staining, western blotting, and TUNEL staining. To investigate the mechanisms of how Lico A exerts anti-AD effects, primary hippocampal neurons were isolated from the AD model mice and treated with Lico A, salubrinal, an eIF2α phosphatase inhibitor, ML385, a Nrf2 inhibitor, or LY294002, an inhibitor of PI3K. Pharmacokinetics and toxicity of Lico A (15 mg/kg) in AD mice were evaluated.

RESULTS

We found that Lico A improved cognitive impairment, decreased Aβ plaques, inhibited ER stress, and reduced neuronal apoptosis in the hippocampus and cortex of AD mice. Treatment with Lico A in primary hippocampal neurons exerted the same effects as it did in vivo. Additionally, cotreatment with ML385 or LY294002 significantly impeded the effects of Lico A against ER stress. Moreover, 15 mg/kg Lico A had a good bioavailability and low toxicity in AD mice.

CONCLUSION

Our results demonstrated that Lico A ameliorates ER stress-induced neuronal apoptosis by inhibiting PERK/eIF2α/ATF4/CHOP signaling, suggesting the therapeutic potential of Lico A in AD treatment.

Exploring the mechanism of chondroitin sulfate-selenium nanoparticles in improving Alzheimer's disease: Insights from intestinal flora evaluation

In this study we have investigated the effect of chondroitin sulfate-selenium nanoparticles (CS@Se) on Alzheimer's disease (AD) mice using 16S rDNA technique. We randomly divided 30 SPF grade male C57BL/6 J mice into 6 groups according to random number table method. The AD mouse model was established by subcutaneous injection of D-galactose (D-gal) combined with gavage of AlCl3 for 30 consecutive days, and then drug intervention was performed in the administration group for 40 consecutive days. The findings demonstrated several positive effects of CS@Se on AD mice. Firstly, CS@Se improved spatial learning and memory problems and reduces anxiety in AD mice. It also significantly reduced pyramidal cell arrangement disorder and rupture, leading to an improvement in synaptic structure damage between hippocampal neurons. Furthermore, CS@Se reduced mitochondrial swelling and vacuolation while increasing neuron survival in AD mice. Moreover, CS@Se significantly impacted the diversity and richness of intestinal flora in AD mice. It increased the relative abundance of Firmicutes and Actinobacteria while reducing the relative abundance of Bacteroidetes and Proteobacteria. In conclusion, CS@Se effectively reduced the breakdown of hippocampal pyramidal cells, improved the superfiber structure of hippocampal neurons, and restored intestinal flora balance, ultimately contributing to improving learning and memory abilities and alleviating anxiety in AD mice.

Corilagin improves cognitive impairment in APP/PS1 mice by reducing Aβ generation and enhancing synaptic plasticity

Alzheimer's disease (AD) is closely associated with the neurotoxic effects of amyloid-β (Aβ), leading to synaptic damage, neuronal loss and cognitive dysfunction. Previous in vitro studies have demonstrated the potential of corilagin to counteract Aβ-induced oxidative stress, inflammatory injury, and β-site amyloid precursor protein cleaving enzyme-1 (BACE1) activity in Aβ production. However, the in vivo protective effects of corilagin on Alzheimer's disease remain unexplored. The purpose of this study was to investigate the protective effects of corilagin on APP/PS1 mice and the underlying mechanisms. The cognitive function of the mice was assessed by step-through passive avoidance and Morris water maze tests. Nissl staining was used to evaluate neuronal damage in the hippocampus. ELISA and Western blotting analyses were used to determine the associated protein expression. Transmission electron microscopy was utilized to observe the synaptic ultrastructure of hippocampal neurons. Golgi staining was applied to assess dendritic morphology and dendritic spine density in hippocampal pyramidal neurons. Immunohistochemistry and Western blotting were performed to examine the expression of synaptic-associated proteins. The results showed that corilagin improves learning and memory in APP/PS1 mice, reduces hippocampal neuron damage, inhibits BACE1 and reduces Aβ generation. It also improves synaptic plasticity and the expression of synaptic-associated proteins. Corilagin effectively reduces Aβ generation by inhibiting BACE1, ultimately reducing neuronal loss and enhancing synaptic plasticity to improve synaptic transmission. This study sheds light on the potential therapeutic role of corilagin in Alzheimer's disease.

Identification of cuproptosis-related genes in Alzheimer's disease based on bioinformatic analysis

OBJECTIVE

To explore the role of cuproptosis in Alzheimer's disease (AD).

METHODS

An AD-related microarray dataset was downloaded from the Gene Expression Omnibus (GEO) database (GSE140830). Weighted gene co-expression network analysis was used to identify AD-related modular genes. The Venn analysis was performed to obtain module genes associated with apoptosis and cuproptosis. Besides, we conducted an enrichment analysis of overlapped genes and constructed the protein-protein interaction (PPI) network, followed by screening hub genes and those significantly associated with AD were used to construct models of apoptosis and cuproptosis, respectively. Further, receiver operating characteristic (ROC) curve analysis, decision curve analysis (DCA), and subgroup analysis were used to compare the AD prediction performance of two models. Finally, the accuracy and reliability of AD prediction models were verified by GSE26927.

RESULTS

We obtained 42 module genes related to apoptosis and 9 module genes related to cuproptosis. The enrichment analysis results revealed MAPK signaling pathway as the common signaling pathway of apoptosis- and cuproptosis-related genes. Next, the hub genes associated with apoptosis (TRADD, FADD, BIRC2, and CASP2) and cuproptosis (MAP2K1, SLC31A1, and PDHB) in AD were identified, which were used to construct apoptosis and cuproptosis models to distinguish AD patients from the control group (P < 0.05). The ROC, DCA, and subgroup analysis results showed that apoptosis-related models and cuproptosis-related models had comparable ability in predicting AD. GSE26927 further confirmed that the two models have comparable predictive effects for AD.

CONCLUSIONS

The cuproptosis model had a certain performance in predicting AD. Three hub genes (MAP2K1, SLC31A1, and PDHB) closely related to cuproptosis in AD might serve as biomarkers for AD diagnosis and treatment.

The Neuroprotective Role of Cyanobacteria with Focus on the Anti-Inflammatory and Antioxidant Potential: Current Status and Perspectives

Neurodegenerative diseases are linked to the process of neurodegeneration. This can be caused by several mechanisms, including inflammation and accumulation of reactive oxygen species. Despite their high incidence, there is still no effective treatment or cure for these diseases. Cyanobacteria have been seen as a possible source for new compounds with anti-inflammatory and antioxidant potential, such as polysaccharides (sacran), phycobiliproteins (phycocyanin) and lipopeptides (honaucins and malyngamides), which can be interesting to combat neurodegeneration. As a promising case of success, Arthrospira (formerly Spirulina) has revealed a high potential for preventing neurodegeneration. Additionally, advantageous culture conditions and sustainable production of cyanobacteria, which are allied to the development of genetic, metabolic, and biochemical engineering, are promising. The aim of this review is to compile and highlight research on the anti-inflammatory and antioxidant potential of cyanobacteria with focus on the application as neuroprotective agents. Also, a major goal is to address essential features that brand cyanobacteria as an ecoefficient and economically viable option, linking health to sustainability.

Quality-of-Life- and Cognitive-Oriented Rehabilitation Program through NeuronUP in Older People with Alzheimer's Disease: A Randomized Clinical Trial

(1) Background: Alzheimer's disease (AD) is a progressive neurodegenerative disorder marked by cognitive decline and functional impairment. The NeuronUP platform is a computer program whose main function is cognitive stimulation through three types of activities that change so that the user does not manage to learn it. This program provides opportunities to work on various domains, including activities of daily living (ADLs), social skills, and cognitive functions. The main objective of this randomized clinical trial was to assess the impact of integrating the NeuronUP platform with conventional occupational therapy to enhance or maintain cognitive, perceptual, and quality of life (QoL) abilities in people with AD compared to a control group. (2) Methods: A randomized, single-blind clinical trial was conducted. The sample was randomized using a software program, OxMar, which allowed the separation of the sample into a control group (CG) that received their conventional occupational therapy sessions and an experimental group (EG) that received therapy with NeuronUP, in addition to their conventional occupational therapy sessions. An eighteen-week intervention was conducted. (3) Results: The study included 20 participants, and significant differences were observed in most variables analyzed, indicating improvements after the intervention, particularly in measures of QoL and cognitive status. (4) Conclusions: Our findings demonstrate that an eighteen-week experimental protocol, incorporating the NeuronUP platform alongside conventional occupational therapy, led to improvements in cognitive status and QoL in older adults with AD. Thus, integrating the NeuronUP platform as a complementary tool to occupational therapy can be a valuable resource for enhancing the QoL of individuals with AD. However, due to the small sample size, further studies are needed to corroborate these findings.

Integrative analysis reveals key lysosomal genes as potential therapeutic targets in Alzheimer's disease

Alzheimer's disease (AD) is a neurodegenerative disorder with early autophagy deficits. Our study probed the role of lysosomal-related genes (LRGs) in AD. Using the Gene Expression Omnibus (GEO) database, we analyzed differentially expressed genes (DEGs) in AD. AD-related genes and lysosomal-related genes (LRGs) were extracted from public databases. Leveraging the UpSetR package, we identified differentially expressed LRGs (DE-LRGs). Subsequently, consensus cluster analysis was used to stratify AD patients into distinct molecular subtypes based on DE-LRGs. Immune cell patterns were studied via Single-Sample Gene Set Enrichment Analysis (ssGSEA). Molecular pathways were assessed through Gene Set Variation Analysis (GSVA), while Mendelian Randomization (MR) discerned potential gene-AD causations. To reinforce our bioinformatics findings, we conducted in vitro experiments. In total, 52 DE-LRGs were identified, with LAMP1, VAMP2, and CTSB as standout hub genes. Leveraging the 52 DE-LRGs, AD patients were categorized into three distinct molecular subtypes. Interestingly, the three aforementioned hub genes exhibited significant predictive accuracy for AD differentiation across the subtypes. The ssGSEA further illuminated correlations between LAMP1, VAMP2, and CTSB with plasma cells, fibroblasts, eosinophils, and endothelial cells. GSVA analysis underscored significant associations of LAMP1, VAMP2, and CTSB with NOTCH, TGFβ, and P53 pathways. Compellingly, MR findings indicated a potential causative relationship between LAMP1, CTSB, and AD. Augmenting our bioinformatics conclusions, in vitro tests revealed that LAMP1 potentially alleviates AD progression by amplifying autophagic processes. LAMP1 and CTSB emerge as potential AD biomarkers, paving the way for innovative therapeutic interventions.

The Combined Effect of Green Tea, Saffron, Resveratrol, and Citicoline against Neurodegeneration Induced by Oxidative Stress in an In Vitro Model of Cognitive Decline

During ageing, the brain is vulnerable to a growing imbalance of the antioxidant defence system, resulting in increased oxidative stress. This condition may be mainly responsible for cognitive decline, resulting in synaptic transmission disruptions and the onset of neuronal dysfunction. In this context, developing efficient preventive and therapeutic strategies against increased oxidative stress and decreased antioxidant defence mechanisms should be considered a public health priority to promote healthy ageing. Therefore, the current study explored the benefits of a novel combination of green tea, saffron, trans-Reveratrol, and citicoline, called MIX, on improving intracellular processes to ameliorate the mechanisms linked to cognitive decline under oxidative stress conditions. First, the ability of MIX to cross the blood-brain barrier (BBB) was evaluated in an in vitro model, analysing TEER value and the specific tight junctions; second, the CCF-STTG1 cell line was pretreated with 200 µM H2O2 for 30 min to explore the effects of the single active compounds and their combination under oxidative stress conditions. Our results demonstrated for the first time the synergistic effects of the new combination to improve the absorption rate of individual agents through the BBB and maintain its integrity. Subsequently, further research was done to assess the positive role of the combination to counteract oxidative damage; as expected, MIX restored the neurodegenerative state activated by 200 µM H2O2, reducing mitochondrial damage, and improving survival pathways. Additionally, MIX acted as a regulator of both cellular energy metabolism and apoptosis, reducing the inflammatory state activated by oxidative stress. Finally, MIX can balance neurotrophin production to prevent mitochondrial disruption. In conclusion, MIX counteracted the adverse effects of brain oxidative stress, suggesting that this new proposed formulation prevents the molecular mechanisms underlying the onset of cognitive decline, even in support of conventional therapy.

Withania somnifera (Ashwagandha) Improves Spatial Memory, Anxiety and Depressive-like Behavior in the 5xFAD Mouse Model of Alzheimer's Disease

Withania somnifera (WS), also known as ashwagandha, is a popular botanical supplement used to treat various conditions including memory loss, anxiety and depression. Previous studies from our group showed an aqueous extract of WS root (WSAq) enhances cognition and alleviates markers for depression in Drosophila. Here, we sought to confirm these effects in the 5xFAD mouse model of β-amyloid (Aβ) accumulation. Six- to seven-month-old male and female 5xFAD mice were treated with WSAq in their drinking water at 0 mg/mL, 0.5 mg/mL or 2.5 mg/mL for four weeks. In the fourth week of treatment, spatial memory, anxiety and depressive-like symptoms were evaluated. At the conclusion of behavioral testing, brain tissue was harvested, immunohistochemistry was performed, and the cortical expression of antioxidant response genes was evaluated. Both concentrations of WSAq improved spatial memory and reduced depressive and anxiety-related behavior. These improvements were accompanied by a reduction in Aβ plaque burden in the hippocampus and cortex and an attenuation of activation of microglia and astrocytes. Antioxidant response genes were upregulated in the cortex of WSAq-treated mice. Oral WSAq treatment could be beneficial as a therapeutic option in AD for improving disease pathology and behavioral symptoms. Future studies focused on dose optimization of WSAq administration and further assessment of the mechanisms by which WSAq elicits its beneficial effects will help inform the clinical potential of this promising botanical therapy.

Epigallocatechin-3-Gallate Inhibits Oxidative Stress Through the Keap1/Nrf2 Signaling Pathway to Improve Alzheimer Disease

Alzheimer disease (AD) is a common neurodegenerative disease with an intricate pathophysiological mechanism. Oxidative stress has been shown in several investigations as a significant factor in AD progression. For instance, studies have confirmed that oxidative stress inhibition may considerably improve AD symptoms, with potent antioxidants being touted as a possible interventional strategy in the search for AD treatment. Epigallocatechin-3-gallate (EGCG) acts as a natural catechin that has antioxidant effect. It activates the kelch-like epichlorohydrin-associated proteins (Keap1)/nuclear factor erythroid 2-related factor 2 (Nrf2) signaling pathway to inhibit oxidative stress. The Keap1/Nrf2 signal pathway is not only an upstream signaling target for a variety of antioxidant enzymes, but also minimizes high levels of reactive oxygen species. This report analyzes the antioxidant effect of EGCG in AD, elaborates its specific mechanism of action, and provides a theoretical basis for its clinical application in AD.

Neuroprotective Effect of Codonopsis pilosula Polysaccharide on Aβ25-35-Induced Damage in PC12 Cells via the p38MAPK Signaling Pathways

OBJECTIVES

Plant polysaccharides have attracted increasing attention due to their high efficiency and low toxicity. Codonopsis pilosula polysaccharide (CPP) is an essential substance extracted from Codonopsis pilosula, known for its excellent antioxidant and neuroprotective effects. However, it is still unclear how CPP improves nerve protection and what its underlying molecular mechanisms are. This study aimed to investigate the neuroprotective effect of CPP on Aβ25-35-induced damage in PC12 cells and its underlying molecular mechanisms.

METHODS

The neuroprotective effect of CPP was evaluated using Aβ25-35-induced damage in pheochFfromocytoma (PC12) cells as an in vitro cell model. The cells were treated with CPP alone or in combination with SB203580 (an inhibitor of p38MAPK) in Aβ25-35 culture. The cell viability was assessed using a 3-(4,5-Dimethylthiazol-2-yl)-2,diphenyltetrazolium (MTT) assay. Furthermore, reactive oxygen species (ROS) were detected using flow cytometry. The production levels of intracellular superoxide dismutase (SOD), dismutase (SOD), glutathione (GSH), catalase (CAT), and malondialdehyFde (MDA) were determined using the colorimetric method. Annexin V-FITC and propidium iodide (PI) staining, as well as 33258 were performed using fluorescence microscopy. Moreover, the effect of adding SB203580 was studied to determine the changes in cell apoptosis induced by CPP treatment and Aβ25-35 induction.

RESULTS

The CPP markedly inhibited Aβ25-35-induced reduction in the viability and apoptosis of PC12 cells. CPP also reduced the Aβ25-35-induced increase in the expression of the apoptosis factors and the levels of free radicals (ROS and MDA) and reversed the Aβ25-35-induced suppression of antioxidant activity. Additionally, inhibition of p38MAPK via the addition of their antagonists reversed the observed anti-apoptosis effects of CPP.

CONCLUSIONS

CPP can efficiently provide neuroprotection against Aβ25-35-induced damage in PC12 cells brought about via oxidation and apoptosis reactions, and the underlying mechanisms involve the p38MAPK pathways. Therefore, CPP could potentially be useful as a neuroprotective agent in natural medicine, pharmacy, and the food industry.

Cerebroprotein hydrolysate-I ameliorates cognitive dysfunction in APP/PS1 mice by inhibiting ferroptosis via the p53/SAT1/ALOX15 signalling pathway

Ferroptosis, an iron-dependent lipid peroxidation-driven cell death pathway, has been linked to the development of Alzheimer's disease (AD). However, the role of ferroptosis in the pathogenesis of AD remains unclear. Cerebroprotein hydrolysate-I (CH-I) is a mixture of peptides with neurotrophic effects that improves cognitive deficits and reduces amyloid burden. The present study investigated the ferroptosis-induced signalling pathways and the neuroprotective effects of CH-I in the brains of AD transgenic mice. Seven-month-old male APPswe/PS1dE9 (APP/PS1) transgenic mice were treated with intraperitoneal injections of CH-I and saline for 28 days. The Morris water maze test was used to assess cognitive function. CH-I significantly improved cognitive deficits and attenuated beta-amyloid (Aβ) aggregation and tau phosphorylation in the hippocampus of APP/PS1 mice. RNA sequencing revealed that multiple genes and pathways, including ferroptosis-related pathways, were involved in the neuroprotective effects of CH-I. The increased levels of lipid peroxidation, ferrous ions, reactive oxygen species (ROS), and altered expression of ferroptosis-related genes (recombinant solute carrier family 7, member 11 (SLC7A11), spermidine/spermine N1-acetyltransferase 1 (SAT1) and glutathione peroxidase 4 (GPX4)) were significantly alleviated after CH-I treatment. Quantitative real-time PCR and western blotting were performed to investigate the expression of key ferroptosis-related genes and the p53/SAT1/arachidonic acid 15-lipoxygenase (ALOX15) signalling pathway. The p53/SAT1/ALOX15 signalling pathway was found to be involved in mediating ferroptosis, and the activation of this pathway was significantly suppressed in AD by CH-I. CH-I demonstrated neuroprotective effects against AD by attenuating ferroptosis and the p53/SAT1/ALOX15 signalling pathway, thus providing new targets for AD treatment.

Neuroprotective effect and preparation methods of berberine

Berberine (BBR) is a natural alkaloid, which has played an important role in the field of medicine since its discovery in the late 19th century. However, the low availability of BBR in vivo prevents its full effect. In recent years, a large number of studies confirmed that BBR has a protective effect on the nervous system through various functions, yet the issue of the inability to systematically understand the protection of BBR on the nervous system remains a gap that needs to be addressed. Many existing literature introductions about berberine in neurodegenerative diseases, but the role of berberine in the nervous system goes far beyond these. Different from these literatures, this review is divided into three parts: preparation method, mechanism, and therapeutic effect. Various dosage forms of BBR and their preparation methods are added, in order to provide a reasonable choice of BBR, and help to solve the problem of low bioavailability in treatment. More importantly, we more comprehensively summarize the mechanism of BBR to protect the nervous system, in addition to the treatment of neurodegenerative diseases (anti-oxidative stress, anti-neuroinflammation, regulation of apoptosis), two extra mechanisms of berberine for the protection of the nervous system were also introduced: bidirectional regulation of autophagy and promote angiogenesis. Also, we have clarified the precise mechanism by which BBR has a therapeutic effect not only on neurodegenerative illnesses but also on multiple sclerosis, gliomas, epilepsy, and other neurological conditions. To sum up, we hope that these can evoke more efforts to comprehensively utilize of BBR nervous system, and to promote the application of BBR in nervous system protection.

Effects of transcranial direct current stimulation on different cognitive domains in Alzheimer's disease: a meta-study

BACKGROUND

Numerous studies have investigated the potential effects of transcranial direct current stimulation (tDCS) on improving symptoms related to Alzheimer's disease (AD). However, these studies have produced inconsistent results, leading to a need for further investigation.

METHODS

A comprehensive search was conducted, including articles published from the initial availability date to 5 April 2024. The extracted study data were analyzed using STATA 12.0 software. The standard mean difference (SMD) and a 95% confidence interval (CI) were calculated to assess the effects of tDCS.

RESULTS

A total of 18 studies assessing the effects of tDCS on AD were included in the study. The study revealed that tDCS has an immediate positive impact on general cognitive, executive, language, and visuospatial function. However, the study did not observe any other significant effect of tDCS treatment on improvements in brain function, including long-term effects on general cognitive, attention, language, and memory function, as well as immediate effects on attention and memory function.

CONCLUSIONS

In conclusion, the study suggests that tDCS may be a promising intervention for improving the cognitive function of patients with AD. However, given the complex and multifactorial nature of AD, further well-designed studies with larger sample sizes are necessary to clarify the effectiveness of tDCS and determine the optimal combination of tDCS parameters.

Exploring the triad: VPS35, neurogenesis, and neurodegenerative diseases

Vacuolar protein sorting 35 (VPS35), a critical component of the retromer complex, plays a pivotal role in the pathogenesis of neurodegenerative diseases (NDs). It is involved in protein transmembrane sorting, facilitating the transport from endosomes to the trans-Golgi network (TGN) and plasma membrane. Recent investigations have compellingly associated mutations in the VPS35 gene with neurodegenerative disorders such as Parkinson's and Alzheimer's disease. These genetic alterations are implicated in protein misfolding, disrupted autophagic processes, mitochondrial dysregulation, and synaptic impairment. Furthermore, VPS35 exerts a notable impact on neurogenesis by influencing neuronal functionality, protein conveyance, and synaptic performance. Dysregulation or mutation of VPS35 may escalate the progression of neurodegenerative conditions, underscoring its pivotal role in safeguarding neuronal integrity. This review comprehensively discusses the role of VPS35 and its functional impairments in NDs. Furthermore, we provide an overview of the impact of VPS35 on neurogenesis and further explore the intricate relationship between neurogenesis and NDs. These research advancements offer novel perspectives and valuable insights for identifying potential therapeutic targets in the treatment of NDs.

The Possible Associations between Tauopathies and Atherosclerosis, Diabetes Mellitus, Dyslipidemias, Metabolic Syndrome and Niemann-Pick Disease

Clinical evaluation and treatment of tauopathic syndromes remain a challenge. There is a growing interest in theories concerning their possible associations with metabolic diseases. The possible connection between those diseases might be linked with cerebrovascular dysfunction. The endothelial cell damage and impairment of the blood-brain barrier observed in atherosclerosis or diabetes may play a role in contributing to tauopathic syndrome development. Additionally, the inflammation evoked by pathological metabolic changes may also be involved in this process. Multiple cases indicate the coexistence of metabolic disorders and tauopathic syndromes. These findings suggest that modifying the evolution of metabolic and cerebrovascular diseases may impact the course of neurodegenerative diseases. Obtained data could indicate the possible benefits of introducing routine carotid artery sonography, revascularization operation or antihypertensive medications among patients at high risk for tauopathies. This review has identified this understudied area, which is currently associated with several diseases for which there is no treatment. Due to the pathomechanisms linking metabolic diseases and tauopathies, further investigation of this area of research, including cohort studies, is recommended and may provide new pharmacological perspectives for treatment.

Current research progress on Prevotella intermedia and associated diseases

Prevotella intermedia is a Gram-negative anaerobic bacterium that is a common pathogen of periodontitis. Recent studies have revealed that P. intermedia is closely associated with a variety of diseases involving multiple systems. Under the action of its virulence factors such as cysteine protease and adhesins, P. intermedia has the ability to bind and invade various host cells including gingival fibroblasts. It can also copolymerize a variety of pathogenic bacteria, leading to interference with the host's immune inflammatory response and causing various diseases. In this article, we review the progress of research on P. intermedia virulence factors and bacterial pathogenesis, and the correlation between P. intermedia and various diseases.

m5C RNA methylation: a potential mechanism for infectious Alzheimer's disease

Alzheimer's disease (AD) is a neurodegenerative disorder caused by a variety of factors, including age, genetic susceptibility, cardiovascular disease, traumatic brain injury, and environmental factors. The pathogenesis of AD is largely associated with the overproduction and accumulation of amyloid-β peptides and the hyperphosphorylation of tau protein in the brain. Recent studies have identified the presence of diverse pathogens, including viruses, bacteria, and parasites, in the tissues of AD patients, underscoring the critical role of central nervous system infections in inducing pathological changes associated with AD. Nevertheless, it remains unestablished about the specific mechanism by which infections lead to the occurrence of AD. As an important post-transcriptional RNA modification, RNA 5-methylcytosine (m5C) methylation regulates a wide range of biological processes, including RNA splicing, nuclear export, stability, and translation, therefore affecting cellular function. Moreover, it has been recently demonstrated that multiple pathogenic microbial infections are associated with the m5C methylation of the host. However, the role of m5C methylation in infectious AD is still uncertain. Therefore, this review discusses the mechanisms of pathogen-induced AD and summarizes research on the molecular mechanisms of m5C methylation in infectious AD, thereby providing new insight into exploring the mechanism underlying infectious AD.

Enhancing Outcomes in Alzheimer's Disease: Exploring the Effects of a Diversified Rehabilitation Program Combined with Donepezil on Apathy, Cognitive Function, and Family Caregiver Burden

BACKGROUND AND OBJECTIVE

Alzheimer's disease is a progressive neurodegenerative disorder characterized by cognitive decline, behavioral changes, and functional impairments. Apathy, a common symptom in Alzheimer's disease, refers to a lack of motivation, interest, and emotional responsiveness. It can significantly impact patients' quality of life and increase caregiver burden. This study aimed to determine the effects of a diversified rehabilitation program combined with donepezil on apathy, cognitive function, and family caregiver burden of Alzheimer's disease patients.

METHODS

A total of 105 Alzheimer's disease patients treated at our hospital between January 2020 and January 2023 were selected and analyzed retrospectively. They were assigned to the control group (n = 50) or the observation group (n = 55). The two groups did not differ in terms of general data such as age and sex. All patients were treated with donepezil orally. The control group was given routine nursing, whereas the observation group was given a diversified rehabilitation program intervention, including cognitive training and emotional support. The Hasegawa's dementia scale, mini-mental state examination, and Montreal cognitive assessment scale were adopted to evaluate the cognitive function of the two groups before and after treatment. A caregiver burden scale, the Zarit Burden Interview (ZBI) and the Apathy Evaluation Scale Informant version (AES-I) were used to evaluate the caregiver burden and apathy of the two groups.

RESULTS

A significantly higher overall response rate to treatment was found in the observation group (94.55%) than in the control group (80.00%) (p = 0.024). After treatment, scores on the Hasegawa's dementia scale, mini-mental state examination, and Montreal cognitive assessment scale of the two groups increased to varying degrees, with greater increases in the observation group than in the control group (p < 0.05). The ZBI and AES-I scores of the two groups decreased to different degrees after treatment, with greater decreases in the observation group than in the control group (p < 0.05).

CONCLUSION

A diversified rehabilitation program combined with donepezil can substantially alleviate the apathy of Alzheimer's disease patients, improve their cognitive function, and reduce the burden on their families.

Neuronal expression of human amyloid-β and Tau drives global phenotypic and multi-omic changes in C. elegans

Alzheimer's disease (AD) and Alzheimer's related diseases (ADRD) are prevalent age-related neurodegenerative disorders characterized by the accumulation of amyloid-β (Aβ) plaques and Tau neurofibrillary tangles. The nematode Caenorhabditis elegan s ( C. elegans ) serves as an invaluable model organism in diseases of old age-due to its rapid aging. Here we performed an unbiased systems analysis of a C. elegans strain expressing both Aβ and Tau proteins within neurons. We set out to determine if there was a phenotypic interaction between Aβ and Tau. In addition, we were interested in determining the temporal order of the phenotypic and multi-omic (geromic) outcomes. At an early stage of adulthood, we observed reproductive impairments and mitochondrial dysfunction consistent with disruptions in mRNA transcript abundance, protein solubility, and metabolite levels. Notably, the expression of these neurotoxic proteins exhibited a synergistic effect, leading to accelerated aging. Our findings shed light on the close relationship between normal aging and ADRD. Specifically, we demonstrate alterations to metabolic functions preceding age-related neurotoxicity, offering a resource for the development of new therapeutic strategies.

Correlation between Alzheimer's Disease and Gastrointestinal Tract Disorders

Alzheimer's disease is the most common cause of dementia globally. The pathogenesis is multifactorial and includes deposition of amyloid-β in the central nervous system, presence of intraneuronal neurofibrillary tangles and a decreased amount of synapses. It remains uncertain what causes the progression of the disease. Nowadays, it is suggested that the brain is connected to the gastrointestinal tract, especially the enteric nervous system and gut microbiome. Studies have found a positive association between AD and gastrointestinal diseases such as periodontitis, Helicobacter pylori infection, inflammatory bowel disease and microbiome disorders. H. pylori and its metabolites can enter the CNS via the oropharyngeal olfactory pathway and may predispose to the onset and progression of AD. Periodontitis may cause systemic inflammation of low severity with high levels of pro-inflammatory cytokines and neutrophils. Moreover, lipopolysaccharide from oral bacteria accompanies beta-amyloid in plaques that form in the brain. Increased intestinal permeability in IBS leads to neuronal inflammation from transference. Chronic inflammation may lead to beta-amyloid plaque formation in the intestinal tract that spreads to the brain via the vagus nerve. The microbiome plays an important role in many bodily functions, such as nutrient absorption and vitamin production, but it is also an important factor in the development of many diseases, including Alzheimer's disease. Both the quantity and diversity of the microbiome change significantly in patients with AD and even in people in the preclinical stage of the disease, when symptoms are not yet present. The microbiome influences the functioning of the central nervous system through, among other things, the microbiota-gut-brain axis. Given the involvement of the microbiome in the pathogenesis of AD, antibiotic therapy, probiotics and prebiotics, and faecal transplantation are being considered as possible therapeutic options.

Long Non-Coding RNAs and Alzheimer's Disease: Towards Personalized Diagnosis

Alzheimer's disease (AD), a neurodegenerative disorder characterized by progressive cognitive decline, is the most common form of dementia. Currently, there is no single test that can diagnose AD, especially in understudied populations and developing countries. Instead, diagnosis is based on a combination of medical history, physical examination, cognitive testing, and brain imaging. Exosomes are extracellular nanovesicles, primarily composed of RNA, that participate in physiological processes related to AD pathogenesis such as cell proliferation, immune response, and neuronal and cardiovascular function. However, the identification and understanding of the potential role of long non-coding RNAs (lncRNAs) in AD diagnosis remain largely unexplored. Here, we clinically, cognitively, and genetically characterized a sample of 15 individuals diagnosed with AD (cases) and 15 controls from Barranquilla, Colombia. Advanced bioinformatics, analytics and Machine Learning (ML) techniques were used to identify lncRNAs differentially expressed between cases and controls. The expression of 28,909 lncRNAs was quantified. Of these, 18 were found to be differentially expressed and harbored in pivotal genes related to AD. Two lncRNAs, ENST00000608936 and ENST00000433747, show promise as diagnostic markers for AD, with ML models achieving > 95% sensitivity, specificity, and accuracy in both the training and testing datasets. These findings suggest that the expression profiles of lncRNAs could significantly contribute to advancing personalized AD diagnosis in this community, offering promising avenues for early detection and follow-up.

Nanozymes: Potential Therapies for Reactive Oxygen Species Overproduction and Inflammation in Ischemic Stroke and Traumatic Brain Injury

Nanozymes, which can selectively scavenge reactive oxygen species (ROS), have recently emerged as promising candidates for treating ischemic stroke and traumatic brain injury (TBI) in preclinical models. ROS overproduction during the early phase of these diseases leads to oxidative brain damage, which has been a major cause of mortality worldwide. However, the clinical application of ROS-scavenging enzymes is limited by their short in vivo half-life and inability to cross the blood-brain barrier. Nanozymes, which mimic the catalytic function of natural enzymes, have several advantages, including cost-effectiveness, high stability, and easy storage. These advantages render them superior to natural enzymes for disease diagnosis and therapeutic interventions. This review highlights recent advancements in nanozyme applications for ischemic stroke and TBI, emphasizing their potential to mitigate the detrimental effect of ROS overproduction, oxidative brain damage, inflammation, and blood-brain barrier compromise. Therefore, nanozymes represent a promising treatment modality for ROS overproduction conditions in future medical practices.

Network pharmacology and experimental verification to explore the effect of Hedyotis diffusa on Alzheimer's disease

This study aimed to explore the active components and the effect of Hedyotis diffusa (HD) against Alzheimer's disease (AD) via network pharmacology, molecular docking, and experimental evaluations. We conducted a comprehensive screening process using the TCMSP, Swiss Target Prediction, and PharmMapper databases to identify the active components and their related targets in HD. In addition, we collected potential therapeutic targets of AD from the Gene Cards, Drugbank, and OMIM databases. Afterward, we utilized Cytoscape to establish both protein-protein interaction (PPI) networks and compound-target (C-T) networks. To gain further insights into the functional aspect, we performed GO and KEGG pathway analyses using the David database. Next, we employed Autodock vina to estimate the binding force between the components and the hub genes. To validate our network pharmacology findings, we conducted relevant experiments on Caenorhabditis elegans, further confirming the reliability of our results. Then a total of six active compounds and 149 therapeutic targets were detected. Through the analysis of the association between active compounds, therapeutic targets, and signaling pathways, it was observed that the therapeutic effect of HD primarily encompassed the inhibition of Aβ, suppression of AChE activity, and mitigating oxidative stress. Additionally, our investigation revealed that the key active compounds in HD primarily consisted of iridoids, which exhibited resistance against AD by acting on the Alzheimer's disease pathway and the AGE-RAGE signaling pathway in diabetic complications.

Mitochondrial disorders leading to Alzheimer's disease-perspectives of diagnosis and treatment

Alzheimer's disease (AD) is a neurodegenerative disorder and the most common cause of dementia globally. The pathogenesis of AD remains still unclear. The three main features of AD are extracellular deposits of amyloid beta (Aβ) plaque, accumulation of abnormal formation hyper-phosphorylated tau protein, and neuronal loss. Mitochondrial impairment plays an important role in the pathogenesis of AD. There are problems with decreased activity of multiple complexes, disturbed mitochondrial fusion, and fission or formation of reactive oxygen species (ROS). Moreover, mitochondrial transport is impaired in AD. Mouse models in many research show disruptions in anterograde and retrograde transport. Both mitochondrial transportation and network impairment have a huge impact on synapse loss and, as a result, cognitive impairment. One of the very serious problems in AD is also disruption of insulin signaling which impairs mitochondrial Aβ removal.Discovering precise mechanisms leading to AD enables us to find new treatment possibilities. Recent studies indicate the positive influence of metformin or antioxidants such as MitoQ, SS-31, SkQ, MitoApo, MitoTEMPO, and MitoVitE on mitochondrial functioning and hence prevent cognitive decline. Impairments in mitochondrial fission may be treated with mitochondrial division inhibitor-1 or ceramide.

MAO-B Inhibitor (2E)-3-(4-Bromophenyl)-1-(1H-indol-3-yl) prop-2-en-1-one as a Neuroprotective Agent Against Alzheimer's Disease

Chalcones (trans-1,3-diphenyl-2-propen-1-ones) form simple chemical structures that act as precursors for the biogenesis of flavonoids. These are distributed in plants and have two aromatic or heteroaromatic rings connected by a three-carbon α, β-unsaturated carbonyl group. Considering the importance of chalcones as monoamine oxidase and acetylcholinesterase inhibitors, the study was designed as a comprehensive and systematic analysis to evaluate the pharmacological activities leading to the formation of drug molecules against Alzheimer's disease (AD). Based on our previous research, 11 indolyl chalcones (IC1-IC11) were synthesised and investigated for MAO-B inhibitory activity. The inhibitory potential was evaluated based on binding and reversibility studies using purified enzymes. The active and most promising molecule, (2E)-3-(4-bromophenyl)-1-(1H-indol-3-yl) prop-2-en-1-one (IC9), also found predominant acetylcholinesterase inhibition and hence it was found dual acting in vitro. Based on this, the molecule IC9 was further subjected to cell line studies to further explore its role as a neuroprotective agent against neuronal degeneration, one of the main contributing parameters related to AD.