Patient with frontal-variant syndrome in early-onset Alzheimer's disease

The clinical manifestation of frontal-variant Alzheimer’s disease(fvAD)is not typical,and it is difficult yet necessary to differentiate fvAD from frontal-variant frontal temporal dementia(fvFD).We describe a patient with early-onset Alzheimer's disease(AD)who presented with an fvFTD-like syndrome and apolipoprotein E ε3/ε4 genotype.A brain amyloid imaging procedure,11 C-Pittsburgh compound B positron emission tomography(PET),supported the final diagnosis of AD.Our present case highlights the clinical variability that characterises early-onset AD.A multimodal approach is crucial when assessing rare forms of dementia.

Early-Onset Alzheimer’s Disease and Metabolic Dysfunction, a Comparative Review

Alzheimer’s disease is quickly becoming one of the most known diseases in the country due to its devastating effects and lack of treatment options. Within this lethal disease, there is a smaller group, those individuals that are diagnosed with early-onset Alzheimer’s disease. It is understood that these individuals see faster effects of the disease and die considerably sooner, but it is not understood why. This review compares the early-onset (EOAD) and late-onset (LOAD) types to try and determine some of the most blaring differences between the two. The genetic basis linking EOAD and LOAD has been the apolipoprotein E gene (APOE) to indicate metabolic alteration with the ε4 allele specifically. The topographical atrophy disparities between EOAD and LOAD supported the more noticeable cognitive differences between the two Alzheimer’s disease categories. The faster and wider spread atrophy of EOAD patients correlates with the difficulty they experience with attention, language, visuo-spatial, and executive functions. Finally, brain metabolism differs between both AD subtypes as well, where EOAD indicates the wide spread damage and metabolic breakdown across more diverse regions of the brain.

C677T and A1298C gene polymorphisms and sporadic early-onset Alzheimer’s disease

Alzheimer’s disease (AD) is a genetically complex and heterogeneous disorder. Although the clinical manifestations and the pathological features have been well elucidated, a clear etiology of AD is still unknown to this day. In the past few decades, investigations have elucidated that both the genetic and the environmental factors are capable of causing the development of AD. We report a patient with clinically diagnosed earlyonset Alzheimer's disease, age of onset 45 years. Genetic analysis revealed two MTHFR heterozygous polymorphisms C677T and A1298C.

Case of early-onset Alzheimer’s disease with atypical manifestation

Short-term memory decline is the typical clinical manifestation of Alzheimer’s disease(AD).However,early-onset AD usually has atypical symptoms and may get misdiagnosed.In the present case study,we reported a patient who experienced symptoms of memory loss with progressive non-fluent aphasia accompanied by gradual social withdrawal.He did not meet the diagnostic criteria of AD based on the clinical manifestation and brain MRI.However,his cerebrospinal fluid examination showed a decreased level of beta-amyloid 42,and increased total tau and phosphorylated tau.Massive amyloid β-protein deposition by 11C-Pittsburgh positron emission tomography confirmed the diagnosis of frontal variant AD.This case indicated that early-onset AD may have progressive non-fluent aphasia as the core manifestation.The combination of individual and precision diagnosis would be beneficial for similar cases.

Humanin蛋白在Alzheimer’s病模型中神经保护作用的研究进展

研究表明,Humanin蛋白通过多种方式在抗Alzheimer’s病的过程中发挥神经保护作用。本综述从Humanin的发现、结构特征、神经保护的机制及其新型同源分泌肽Rattin的结构与功能方面介绍Humanin蛋白在Alzheimer’s病中神经保护作用的最新研究进展。

肠道菌群与Alzheimer’s病的研究进展

Alzheimer’s病(AD)是好发于老年人的CNS退行性疾病,以认知能力下降及记忆受损为特征,同时伴发精神症状,严重影响患者的日常生活。肠道菌群是居住在胃肠道中的所有微生物的集合,是人体不可分割的一部分。肠道菌群可以通过脑-肠轴影响CNS,从而增加AD的发生风险。目前获批用于治疗AD的传统药物治疗效果不理想,因此急需一种新的AD治疗方法。本文将对肠道菌群与AD的关系进行阐述,探寻以肠道菌群为靶点的AD新疗法。

Autolysosomal acidification impairment as a mediator for TNFR1 induced neuronal necroptosis in Alzheimer’s disease

Neuronal necroptosis-an emerging form of regulated cell death associated with neuroinflammatory signaling:Alzheimer’s disease(AD)is characterized by the presence of extracellular amyloid-β(Aβ)plaques and intracellular tau neurofibrillary tangles as well as progressive neuronal loss.Recent evidence has suggested that prolonged neuroinflammation with increased levels of cytokines,arising from neuronal injury,innate immune responses from glial cells,and peripheral inflammation,leads to neuronal death and AD progression.

p38-MAPK and CDK5,signaling pathways in neuroinflammation:a potential therapeutic intervention in Alzheimer's disease?

Alzheimer’s disease(AD),the most common type of dementia,affects millions of people worldwide,putting a significant strain on healthcare infrastructure and societal resources.AD is characte rized by the build-up of amyloid-beta(Aβ)plaques and neurofibrillary to ngles containing hyperphosphorylated tau protein.

Targeting tau in Alzheimer's disease:from mechanisms to clinical therapy

Alzheimer’s disease is the most prevalent neurodegenerative disease affecting older adults.Primary features of Alzheimer’s disease include extra cellular aggregation of amyloid-βplaques and the accumulation of neurofibrillary tangles,fo rmed by tau protein,in the cells.While there are amyloid-β-ta rgeting therapies for the treatment of Alzheimer’s disease,these therapies are costly and exhibit potential negative side effects.Mounting evidence suggests significant involvement of tau protein in Alzheimer’s disease-related neurodegeneration.As an important microtubule-associated protein,tau plays an important role in maintaining the stability of neuronal microtubules and promoting axonal growth.In fact,clinical studies have shown that abnormal phosphorylation of tau protein occurs before accumulation of amyloid-βin the brain.Various therapeutic strategies targeting tau protein have begun to emerge,and are considered possible methods to prevent and treat Alzheimer’s disease.Specifically,abnormalities in post-translational modifications of the tau protein,including aberrant phosphorylation,ubiquitination,small ubiquitin-like modifier(SUMO)ylation,acetylation,and truncation,contribute to its microtubule dissociation,misfolding,and subcellular missorting.This causes mitochondrial damage,synaptic impairments,gliosis,and neuroinflammation,eventually leading to neurodegeneration and cognitive deficits.This review summarizes the recent findings on the underlying mechanisms of tau protein in the onset and progression of Alzheimer’s disease and discusses tau-targeted treatment of Alzheimer’s disease.

Activation of autophagy by Citri Reticulatae Semen extract ameliorates amyloid-beta-induced cell death and cognition deficits in Alzheimer’s disease

Amyloid-beta-induced neuronal cell death contributes to cognitive decline in Alzheimer’s disease.Citri Reticulatae Semen has diverse beneficial effects on neurodegenerative diseases,including Parkinson’s and Huntington’s diseases,however,the effect of Citri Reticulatae Semen on Alzheimer’s disease remains unelucidated.In the current study,the anti-apoptotic and autophagic roles of Citri Reticulatae Semen extract on amyloid-beta-induced apoptosis in PC12 cells were first investigated.Citri Reticulatae Semen extract protected PC12 cells from amyloid-beta-induced apoptosis by attenuating the Bax/Bcl-2 ratio via activation of autophagy.In addition,Citri Reticulatae Semen extract was confirmed to bind amyloid-beta as revealed by biolayer interferometry in vitro,and suppress amyloid-beta-induced pathology such as paralysis,in a transgenic Caenorhabditis elegans in vivo model.Moreover,genetically defective Caenorhabditis elegans further confirmed that the neuroprotective effect of Citri Reticulatae Semen extract was autophagy-dependent.Most importantly,Citri Reticulatae Semen extract was confirmed to improve cognitive impairment,neuronal injury and amyloid-beta burden in 3×Tg Alzheimer’s disease mice.As revealed by both in vitro and in vivo models,these results suggest that Citri Reticulatae Semen extract is a potential natural therapeutic agent for Alzheimer’s disease via its neuroprotective autophagic effects.

Are we close to using Alzheimer blood biomarkers in clinical practice?

Alzheimer's disease(AD) is a progressive neurodegenerative disease histologically characterized by the presence of extraneuronal plaques,mainly formed by the 42-aminoacid isoform of amyloid-(Aβ_(1-42)),and by intraneuronal neurofibrillary to ngles,mainly formed by the tau protein and its hyperphosphorylated isoforms(p-tau).AD is the most common cause of dementia,with an estimated lifetime risk of about 1 in 10 for men and 1 in 5 for women.

Medin synergized with vascular amyloid-beta deposits accelerates cognitive decline in Alzheimer's disease:a potential biomarker

Brain vascular dysfunction in Alzheimer s disease(AD) pathogenesis has become increasingly clea r.Accumulating evidence shows that damaged vascular,including large or small vessels and even neurovascular unit,may accelerate the neuropathological process of AD via disrupting brain hypoperfusion,aberrant angiogenesis,and neuroinflammatory response,etc.Thus,vascular dysfunction makes a substantially contribution to the cognitive decline of AD patients.

Microglial autophagy in neurogenesis:a new player in Alzheimer's disease

While extensive studies have illuminated the impact of Alzheimer's disease(AD) on neuronal survival,there is growing evidence that abnormal postnatal neurogenesis in early AD brains contributes to disease progression.Postnatal neurogenesis serves as a mechanism to replace dead or damaged neurons.New neurons generated from neural stem cells(NSCs) in the subgranular zone(SGZ) of the dentate gyrus integrate into the existing hippocampal circuit.

Suppression of mature TAU isoforms prevents Alzheimer's disease-like amyloid-beta oligomer-induced spine loss in rodent neurons

Introduction:TAU isoforms as disease mediators:The microtubule-associated protein TAU is predominantly present in the axons of neurons under physiological conditions.In Alzheimer’s disease(AD)and related tauopathies,TAU also mislocalizes("TAU missorting")to the soma and the dendrites,where it eventually forms aggregates,the so-called neurofibrillary tangles(for review see Zimmer-Bensch and Zempel,2021;Zempel,2023).

小脑经颅磁刺激技术在Alzheimer’s病认知康复中的研究进展

Alzheimer’s病(AD)是以进行性认知功能障碍和行为损害为主要表现的神经退行性疾病,至今仍缺乏有效的药物治疗手段。经颅磁刺激(TMS)是一种非侵入性脑刺激技术,在改善和调节认知功能方面的作用日益凸显。以往TMS刺激的靶区集中在大脑皮质,但越来越多的研究表明,刺激小脑不仅可以调节大脑运动皮质区,并且对远隔的大脑认知相关脑区有调控和整合作用。因此,小脑已逐渐成为AD认知康复的非侵入性调控治疗潜在靶点。本文总结了小脑参与认知功能调控的解剖和功能基础以及小脑TMS调控认知功能的相关研究进展。

Neural stem cells promote neuroplasticity: a promising therapeutic strategy for the treatment of Alzheimer’s disease

Recent studies have demonstrated that neuroplasticity,such as synaptic plasticity and neurogenesis,exists throughout the normal lifespan but declines with age and is significantly impaired in individuals with Alzheimer’s disease.Hence,promoting neuroplasticity may represent an effective strategy with which Alzheimer’s disease can be alleviated.Due to their significant ability to self-renew,differentiate,and migrate,neural stem cells play an essential role in reversing synaptic and neuronal damage,reducing the pathology of Alzheimer’s disease,including amyloid-β,tau protein,and neuroinflammation,and secreting neurotrophic factors and growth factors that are related to plasticity.These events can promote synaptic plasticity and neurogenesis to repair the microenvironment of the mammalian brain.Consequently,neural stem cells are considered to represent a potential regenerative therapy with which to improve Alzheimer’s disease and other neurodegenerative diseases.In this review,we discuss how neural stem cells regulate neuroplasticity and optimize their effects to enhance their potential for treating Alzheimer’s disease in the clinic.

Sorl1 knockout inhibits expression of brain-derived neurotrophic factor:involvement in the development of late-onset Alzheimer's disease

Sortilin-related receptor 1(SORL1)is a critical gene associated with late-onset Alzheimer’s disease.SORL1 contributes to the development and progression of this neurodegenerative condition by affecting the transport and metabolism of intracellularβ-amyloid precursor protein.To better understand the underlying mechanisms of SORL1 in the pathogenesis of late-onset Alzheimer s disease,in this study,we established a mouse model of SorI1 gene knockout using cluste red regularly inters paced short palindro mic repeats-associated protein 9 technology.We found that Sorl1-knocko ut mice displayed deficits in learning and memory.Furthermore,the expression of brain-derived neurotrophic factor was significantly downregulated in the hippocampus and co rtex,and amyloidβ-protein deposits were observed in the brains of 5orl1-knockout mice.In vitro,hippocampal neuronal cell synapses from homozygous Sorl1-knockout mice were impaired.The expression of synaptic proteins,including Drebrin and NR2B,was significantly reduced,and also their colocalization.Additionally,by knocking out the Sorl1 gene in N2a cells,we found that expression of the N-methyl-D-aspartate receptor,NR2B,and cyclic adenosine monophosphate-response element binding protein was also inhibited.These findings suggest that SORL1 participates in the pathogenesis of late-onset Alzheimer s disease by regulating the N-methyl-D-aspartate receptor NR2B/cyclic adenosine monophosphate-response element binding protein signaling axis.

Rebuilding insight into the pathophysiology of Alzheimer’s disease through new blood-brain barrier models

The blood-brain barrier is a unique function of the microvasculature in the brain parenchyma that maintains homeostasis in the central nervous system.Blood-brain barrier breakdown is a common pathology in various neurological diseases,such as Alzheimer’s disease,stroke,multiple sclerosis,and Parkinson’s disease.Traditionally,it has been considered a consequence of neuroinflammation or neurodegeneration,but recent advanced imaging techniques and detailed studies in animal models show that blood-brain barrier breakdown occurs early in the disease process and may precede neuronal loss.Thus,the blood-brain barrier is attractive as a potential therapeutic target for neurological diseases that lack effective therapeutics.To elucidate the molecular mechanism underlying blood-brain barrier breakdown and translate them into therapeutic strategies for neurological diseases,there is a growing demand for experimental models of human origin that allow for functional assessments.Recently,several human induced pluripotent stem cell-derived blood-brain barrier models have been established and various in vitro blood-brain barrier models using microdevices have been proposed.Especially in the Alzheimer’s disease field,the human evidence for blood-brain barrier dysfunction has been demonstrated and human induced pluripotent stem cell-derived blood-brain barrier models have suggested the putative molecular mechanisms of pathological blood-brain barrier.In this review,we summarize recent evidence of blood-brain barrier dysfunction in Alzheimer’s disease from pathological analyses,imaging studies,animal models,and stem cell sources.Additionally,we discuss the potential future directions for blood-brain barrier research.

Genetic and epigenetic targets of natural dietary compounds as anti-Alzheimer's agents

Alzheimer’s disease is a progressive neurodegenerative disorder and the most common cause of dementia that principally affects older adults.Pathogenic factors,such as oxidative stress,an increase in acetylcholinesterase activity,mitochondrial dysfunction,genotoxicity,and neuroinflammation are present in this syndrome,which leads to neurodegeneration.Neurodegenerative pathologies such as Alzheimer’s disease are considered late-onset diseases caused by the complex combination of genetic,epigenetic,and environmental factors.There are two main types of Alzheimer’s disease,known as familial Alzheimer’s disease(onset<65 years)and late-onset or sporadic Alzheimer’s disease(onset≥65 years).Patients with familial Alzheimer’s disease inherit the disease due to rare mutations on the amyloid precursor protein(APP),presenilin 1 and 2(PSEN1 and PSEN2)genes in an autosomaldominantly fashion with closely 100%penetrance.In contrast,a different picture seems to emerge for sporadic Alzheimer’s disease,which exhibits numerous non-Mendelian anomalies suggesting an epigenetic component in its etiology.Importantly,the fundamental pathophysiological mechanisms driving Alzheimer’s disease are interfaced with epigenetic dysregulation.However,the dynamic nature of epigenetics seems to open up new avenues and hope in regenerative neurogenesis to improve brain repair in Alzheimer’s disease or following injury or stroke in humans.In recent years,there has been an increase in interest in using natural products for the treatment of neurodegenerative illnesses such as Alzheimer’s disease.Through epigenetic mechanisms,such as DNA methylation,non-coding RNAs,histone modification,and chromatin conformation regulation,natural compounds appear to exert neuroprotective effects.While we do not purport to cover every in this work,we do attempt to illustrate how various phytochemical compounds regulate the epigenetic effects of a few Alzheimer’s disease-related genes.

Correlative factors of poor prognosis and abnormal cellular immune function in patients with Alzheimer’s disease

BACKGROUND Alzheimer’s disease(AD)is a serious disease causing human dementia and social problems.The quality of life and prognosis of AD patients have attracted much attention.The role of chronic immune inflammation in the pathogenesis of AD is becoming more and more important.AIM To study the relationship among cognitive dysfunction,abnormal cellular immune function,neuroimaging results and poor prognostic factors in patients.METHODS A retrospective analysis of 62 hospitalized patients clinical diagnosed with AD who were admitted to our hospital from November 2015 to November 2020.Collect cognitive dysfunction performance characteristics,laboratory test data and neuroimaging data from medical records within 24 h of admission,including Mini Mental State Examination Scale score,drawing clock test,blood T lymphocyte subsets,and neutrophils and lymphocyte ratio(NLR),disturbance of consciousness,extrapyramidal symptoms,electroencephalogram(EEG)and head nucleus magnetic spectroscopy(MRS)and other data.Multivariate logistic regression analysis was used to determine independent prog-nostic factors.the modified Rankin scale(mRS)was used to determine whether the prognosis was good.The correlation between drug treatment and prognostic mRS score was tested by the rank sum test.RESULTS Univariate analysis showed that abnormal cellular immune function,extrapyramidal symptoms,obvious disturbance of consciousness,abnormal EEG,increased NLR,abnormal MRS,and complicated pneumonia were related to the poor prognosis of AD patients.Multivariate logistic regression analysis showed that the decrease in the proportion of T lym-phocytes in the blood after abnormal cellular immune function(odd ratio:2.078,95%confidence interval:1.156-3.986,P<0.05)was an independent risk factor for predicting the poor prognosis of AD.The number of days of donepezil treatment to improve cognitive function was negatively correlated with mRS score(r=0.578,P<0.05).CONCLUSION The decrease in the proportion of T lymphocytes may have predictive value for the poor prognosis of AD.It is recommended that the proportion of T lymphocytes<55%is used as the cut-off threshold for predicting the poor prog-nosis of AD.The early and continuous drug treatment is associated with a good prognosis.