In the words of the late Sir Colin Blakemore,neurologists have historically sought to infer brain functions in a manner akin to to king a hammer to a computeranalyzing localized anatomical lesions caused by trauma,tum...In the words of the late Sir Colin Blakemore,neurologists have historically sought to infer brain functions in a manner akin to to king a hammer to a computeranalyzing localized anatomical lesions caused by trauma,tumors,or strokes,noting deficits,and inferring what functions certain brain regions may be responsible for.This approach exemplifies a deletion heuristic,where the absence of a specific function reveals insights about the underlying structures or mechanisms responsible for it.By observing what is lost when a particular brain region is damaged,throughout the history of the field,neurologists have pieced together the intricate relationship between anatomy and function.展开更多
Alzheimer’s disease,a devastating neurodegenerative disorder,is characterized by progressive cognitive decline,primarily due to amyloid-beta protein deposition and tau protein phosphorylation.Effectively reducing the...Alzheimer’s disease,a devastating neurodegenerative disorder,is characterized by progressive cognitive decline,primarily due to amyloid-beta protein deposition and tau protein phosphorylation.Effectively reducing the cytotoxicity of amyloid-beta42 aggregates and tau oligomers may help slow the progression of Alzheimer’s disease.Conventional drugs,such as donepezil,can only alleviate symptoms and are not able to prevent the underlying pathological processes or cognitive decline.Currently,active and passive immunotherapies targeting amyloid-beta and tau have shown some efficacy in mice with asymptomatic Alzheimer’s disease and other transgenic animal models,attracting considerable attention.However,the clinical application of these immunotherapies demonstrated only limited efficacy before the discovery of lecanemab and donanemab.This review first discusses the advancements in the pathogenesis of Alzheimer’s disease and active and passive immunotherapies targeting amyloid-beta and tau proteins.Furthermore,it reviews the advantages and disadvantages of various immunotherapies and considers their future prospects.Although some antibodies have shown promise in patients with mild Alzheimer’s disease,substantial clinical data are still lacking to validate their effectiveness in individuals with moderate Alzheimer’s disease.展开更多
Alzheimer's disease(AD)is a neurodegenerative disease characterized by a progressive decline in cognitive functions.Given that AD undermines the quality of life for millions and has an extended asymptomatic period...Alzheimer's disease(AD)is a neurodegenerative disease characterized by a progressive decline in cognitive functions.Given that AD undermines the quality of life for millions and has an extended asymptomatic period,exploring the full AD pathogenesis and seeking the optimal therapeutic solution have become critical and imperative.This allows researchers to intervene,delay,and potentially prevent AD progression.Several clinical imaging methods are utilized routinely to diagnose and monitor AD,such as magnetic resonance imaging(MRI),functional magnetic resonance imaging(fMRI),positron emission tomography(PET),and single photon emission computed tomography(SPECT).Nevertheless,due to their intrinsic drawbacks and restrictions,such as radiation concerns,high cost,long acquisition time,and low spatial resolution,their applications in AD research are limited,especially at the cellular and molecular levels.In contrast,optical microscopic imaging methods overcome these limitations,offering researchers a variety of approaches with distinct advantages to explore AD pathology on diverse models.In this review,we provide a comprehensive overview of commonly utilized optical microscopic imaging techniques in AD research and introduce their contributions to image amyloid beta(Aβ)species.These techniques include fluorescence microscopy(FM),confocal microscopy(CM),two-photon fluorescence microscopy(TPFM),super-resolution microscopy(SRM),expansion microscopy(ExM),and light-sheet fluorescence microscopy(LSFM).In addition,we introduce some related topics,such as the development of near-infrared(NIR)Aβprobes,the Aβplaque hypothesis,and Aβoligomer hypothesis,and the roles of microglia and astrocytes in AD progression.We believe optical microscopic imaging methods continue to play an indispensable role in deciphering the full pathogenesis of AD and advancing therapeutic strategies.展开更多
Pathological and clinical variability in Alzheimer's disease(AD):AD is clinically cha racterized by progressive memory loss and cognitive impairment.From a pathological point of view,the main features of AD are th...Pathological and clinical variability in Alzheimer's disease(AD):AD is clinically cha racterized by progressive memory loss and cognitive impairment.From a pathological point of view,the main features of AD are the deposition of amyloid plaques(composed of amyloid-beta,Aβ)and neurofibrillary tangles containing hyperphosphorylated Tau in the brain,accompanied by neu ronal and synaptic loss,neuroinflammation and brain atrophy(Jellinger,2022).Regardless of these common traits,growing evidence shows increased heterogen eity in the brain of AD patients considering both clinical manifestations and pathological features.展开更多
In the article titled“Activation of autophagy by Citri Reticulatae Semen extract ameliorates amyloid-beta-induced cell death and cognition deficits in Alzheimer’s disease”published on pages 2467-2479,Issue 11,Volum...In the article titled“Activation of autophagy by Citri Reticulatae Semen extract ameliorates amyloid-beta-induced cell death and cognition deficits in Alzheimer’s disease”published on pages 2467-2479,Issue 11,Volume 19 of Neural Regeneration Research(Tang et al.,2024),there are some errors in selecting the appropriate images in Figure 7 by authors during assembling the images.展开更多
BACKGROUND Alzheimer’s disease(AD)is a progressive neurodegenerative disorder currently lacking effective therapeutic interventions.Pathological hallmarks of AD include intracellular neurofibrillary tangles(NFTs)and ...BACKGROUND Alzheimer’s disease(AD)is a progressive neurodegenerative disorder currently lacking effective therapeutic interventions.Pathological hallmarks of AD include intracellular neurofibrillary tangles(NFTs)and extracellular amyloid beta(Aβ)plaques.Neuroplastin 65(NP65),highly expressed in the brain,has been previously shown to mitigate cognitive impairments and decrease Aβplaques in the AD mouse model,suggesting that NP65 is involved in AD neuropathology.However,direct evidence linking NP65 expression to AD pathogenesis in human brain remains absent.AIM To quantify NP65 isoform expression gradients across distinct neuroanatomical regions in the healthy brain and investigate the alterations of NP65 expression in the AD brain.METHODS Immunohistochemical,immunofluorescent and western blot analyses were used to investigate NP65 expression in 19 postmortem brains(AD=10,controls=9).Double immunostaining with 6E10 and or phosphorylated-microtubule-associated protein tau(AT-8,a marker for NFT)markers was performed to assess NP65 colocalization with Aβplaques and NFTs.RESULTS In controls,NP65 was highly expressed in a wide-range of brain areas.AD cases showed significantly increased NP65 immunoreactivity across multiple brain regions,including the frontal and temporal cortex,hippocampus,and cerebellum,compared to controls.Western blot analysis consistently confirmed significantly elevated NP65 expression in the hippocampus of AD patients relative to controls.Double immunostaining demonstrated partial colocalization of NP65 with NFTs and Aβplaques in AD brain tissue.CONCLUSION Our findings demonstrate a significant increase of NP65 protein,which colocalizes with NFTs and Aβplaques in AD brains,providing direct evidence supporting a critical role of NP65 expression in the neuropathological mechanisms of this disease.展开更多
KIT-5/Beta composite supports were synthesized using an in situ self-assembly hydrothermal method,and NiW/KIT-5/Beta catalysts were prepared by impregnation.A series of characterization techniques were utilized to eva...KIT-5/Beta composite supports were synthesized using an in situ self-assembly hydrothermal method,and NiW/KIT-5/Beta catalysts were prepared by impregnation.A series of characterization techniques were utilized to evaluate the influence of varying hydrothermal synthesis temperatures on the physicochemical properties of both the KIT-5/Beta supports and the resulting catalysts.The catalytic performances of catalysts were evaluated under reaction conditions of 320℃,4 MPa H_(2)pressure,and a weight hourly space velocity(WHSV)of 4.8 h^(-1)for hydrodenitrogenation(HDN)of quinoline.The results indicated that the specific surface area and pore structure of the materials could be effectively regulated by adjusting the hydrothermal synthesis temperature,which in turn influenced the number of active sites on the catalyst.The NiW/KB-125 catalyst,synthesized at 125℃,presented the highest quinoline HDN efficiency(96.8%),which can be attributed to its favorable pore channel structure,greater Brønsted acid number,higher degree of metal sulfidation(80.12%)and appropriate metal-support interaction(MSI).展开更多
Currently,our understanding of the pathogenesis of major neurodegenerative disorders,such as Alzheimer's,Parkinson's,and Huntington's diseases,is largely shaped by the amyloid cascade hypothesis.Pa rticula...Currently,our understanding of the pathogenesis of major neurodegenerative disorders,such as Alzheimer's,Parkinson's,and Huntington's diseases,is largely shaped by the amyloid cascade hypothesis.Pa rticularly,this hypothesis posits that in Alzheimer's disease,the aggregation of amyloid-beta peptide initiates a series of pathological processes leading to neuronal dysfunction and death(Zhang et al.,2024).展开更多
Amyloid-β(Aβ)and tau,the two hallmark proteins associated with Alzheimer’s disease(AD),exhibit distinct toxic effects but also interact synergistically within the disease pathology.The prevailing theory in AD patho...Amyloid-β(Aβ)and tau,the two hallmark proteins associated with Alzheimer’s disease(AD),exhibit distinct toxic effects but also interact synergistically within the disease pathology.The prevailing theory in AD pathology-the amyloid cascade hypothesis-highlights the pivotal role of increased processing of the amyloid precursor protein(APP).Initially cleaved by the majorβ-secretase(β-amyloid cleaving enzyme-1,BACE1)in the brain,then undergoes further cleavage by theγ-secretase complex,resulting in the production of Aβ_(40-42)and a set of intracellular C-terminal peptides known as Aβand APP intracellular domain(β-AICDs)and soluble amyloid precursor proteinβ(sAPPβ)(Orobets and Karamyshev,2023).展开更多
e-related macular degeneration (AMD) causes irreversible loss of central vision for which there is no effective treatment. Incipient pathology is thought to occur in the retina for many years before AMD manifests fr...e-related macular degeneration (AMD) causes irreversible loss of central vision for which there is no effective treatment. Incipient pathology is thought to occur in the retina for many years before AMD manifests from midlife onwards to affect a large proportion of the elderly. Although genetic as well as non-genetic/environmental risks are recognized, its complex aetiology makes it difficult to identify susceptibility, or indeed what type of AMD develops or how quickly it progresses in different individuals. Here we summarize the literature describing how the Alzheimer's-linked amyloid beta (Aβ) group of misfolding proteins accumulate in the retina. The discovery of this key driver of Alzheimer's disease in the senescent retina was unexpected and surprising, enabling an altogether different perspective of AMD. We argue that Aβ fundamentally differs from other substances which accumulate in the ageing retina, and discuss our latest findings from a mouse model in which physiological amounts of Aβ were subretinally-injected to recapitulate salient features of early AMD within a short period. Our discoveries as well as those of others suggest the pattern of Aβ accumulation and pathology in donor aged/AMD tissues are closely reproduced in mice, including late-stage AMD phenotypes, which makes them highly attractive to study dynamic aspects of Aβ-mediated retinopathy. Furthermore, we discuss our findings revealing how Aβ behaves at single-cell resolution, and consider the long-term implications for neuroretinal function. We propose Aβ as a key element in switching to a diseased retinal phenotype, which is now being used as a biomarker for latestage AMD.展开更多
Dendrobium nobile Lindl.alkaloids(DNLA),the active ingredients of a traditional Chinese medicine Dendrobium,have been shown to have anti-oxidative effects,anti-inflammatory action,and protective effect on neurons ag...Dendrobium nobile Lindl.alkaloids(DNLA),the active ingredients of a traditional Chinese medicine Dendrobium,have been shown to have anti-oxidative effects,anti-inflammatory action,and protective effect on neurons against oxygen-glucose deprivation.However,it is not clear whether DNLA reduces amyloid-beta(Aβ)-induced neuronal injury.In this study,cortical neurons were treated with DNLA at different concentrations(0.025,0.25,and 2.5 mg/L)for 24 hours,followed by administration of Aβ(25-35)(10μM).Aβ(25-35) treatments increased cell injury as determined by the leakage of lactate dehydrogenase,which was accompanied by chromatin condensation and mitochondrial tumefaction.The damage caused by Aβ(25-35) on these cellular properties was markedly attenuated when cells were pretreated with DNLA.Treatment with Aβ(25-35)down-regulated the expressions of postsynaptic density-95 mRNA and decreased the protein expression of synaptophysin and postsynaptic density-95,all changes were significantly reduced by pretreatment of cells with DNLA.These findings suggest that DNLA reduces the cytotoxicity induced by Aβ(25-35) in rat primary cultured neurons.The protective mechanism that DNLA confers on the synaptic integrity of cultured neurons might be mediated,at least in part,through the upregulation of neurogenesis related proteins synaptophysin and postsynaptic density-95.展开更多
Neurovascular dysfunction,as an integral part of Alzheimer's disease,may have an important influence on the onset and progression of chronic neurodegenerative processes.The bloodbrain barrier(BBB)pathway is one of...Neurovascular dysfunction,as an integral part of Alzheimer's disease,may have an important influence on the onset and progression of chronic neurodegenerative processes.The bloodbrain barrier(BBB)pathway is one of the main pathways that mediates the clearance of amyloidbeta(Aβ)in the brain parenchyma.A large number of studies have shown that receptors and ATPbinding cassette transporte rs expressed on endothelial cells play an important role in Aβtransport across the BBB,but the specific mechanism is not clear.In this review,we summarize the possible mechanisms of Aβproduction and clearance,and in particular the relationship between Aβand brain capillary endothelial cells.Aβis produced by abnormal cleavage of the amyloid precursor protein via amyloidogenic processing under pathological conditions.Dys regulation of Aβclearance is considered to be the main reason for the massive accumulation of Aβin the brain parenchyma.Several pathways mediating Aβclearance from the brain into the periphery have been identified,including the BBB pathway,the blood-cerebros pinal fluid barrier and arachnoid granule pathway,and the lymphoidrelated pathway.Brain ca pilla ry endothelial cells are the key components of Aβclearance mediated by BBB.Receptors(such as LRP1,RAGE,and FcRn)and ATP-binding cassette transporters(such as P-gp,ABCA1,and ABCC1)expressed on endothelial cells play a critical role in Aβtranscytosis across the BBB.The toxic effects of Aβcan induce dysregulation of receptor and transpo rter expression on endothelial cells.Excessive Aβexerts potent detrimental cerebrovascular effects by promoting oxidative stress,inducing chronic inflammation,and impairing endothelial structure and functions.All of these are main causes for the reduction in Aβclearance across the BBB and the accumulation of Aβin the brain parenchyma.Therefo re,studies on the intera ctions between Aβand brain capillary endothelial cells,including their receptors and transporters,studies on inhibition of the toxic effects of Aβon endothelial cells,and studies on promoting the ability of endothelial cells to mediate Aβclearance may provide new therapeutic strategies for Aβclearance in Alzheimer's disease.展开更多
Rare earth elements have unique physical, magnetic, luminescent and catalytic properties. They have been successfully used as medicine and probes in luminescent resonance energy transfer (LRET) for bioassays, as well ...Rare earth elements have unique physical, magnetic, luminescent and catalytic properties. They have been successfully used as medicine and probes in luminescent resonance energy transfer (LRET) for bioassays, as well as reagents for diagnosis in magnetic resonance imaging (MRI). In this progress report, we will focus on recent progress on how rare earth amino complexes bind to DNA and change DNA structure, especially on DNA B-Z transition induced by rare earth amino acid complex and its potential impact on Alzheimer’s disease (AD).展开更多
Amyloid-beta peptide is the main component of amyloid plaques, which are found in Alzhei- mer's disease. The generation and deposition of amyloid-beta is one of the crucial factors for the onset and progression of Al...Amyloid-beta peptide is the main component of amyloid plaques, which are found in Alzhei- mer's disease. The generation and deposition of amyloid-beta is one of the crucial factors for the onset and progression of Alzheimer's disease. Lipid rafts are glycolipid-rich liquid domains of the plasma membrane, where certain types of protein tend to aggregate and intercalate. Lipid rafts are involved in the generation of amyloid-beta oligomers and the formation of amyloid-beta peptides. In this paper, we review the mechanism by which lipid rafts disturb the aberrant deg- radative autophagic-lysosomal pathway of amyloid-beta, which plays an important role in the pathological process of Alzheimer's disease. Moreover, we describe this mechanism from the view of the Two-system Theory of fasciology and thus, suggest that lipid rafts may be a new target of Alzheimer's disease treatment.展开更多
Mounting evidence indicates that amyloid β protein(Aβ) exerts neurotoxicity by disrupting the blood-brain barrier(BBB) in Alzheimer's disease. Hyperoside has neuroprotective effects both in vitro and in vivo ag...Mounting evidence indicates that amyloid β protein(Aβ) exerts neurotoxicity by disrupting the blood-brain barrier(BBB) in Alzheimer's disease. Hyperoside has neuroprotective effects both in vitro and in vivo against Aβ. Our previous study found that hyperoside suppressed Aβ1-42-induced leakage of the BBB, however, the mechanism remains unclear. In this study, bEnd.3 cells were pretreated with 50, 200, or 500 μM hyperoside for 2 hours, and then exposed to Aβ1-42 for 24 hours. Cell viability was determined using 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide assay. Flow cytometry and terminal deoxynucleotidyl transferase-mediated d UTP nick-end labeling assay were used to analyze cell apoptosis. Western blot assay was carried out to analyze expression levels of Bax, Bcl-2, cytochrome c, caspase-3, caspse-8, caspase-9, caspase-12, occludin, claudin-5, zonula occludens-1, matrix metalloproteinase-2(MMP-2), and MMP-9. Exposure to Aβ1-42 alone remarkably induced bEnd.3 cell apoptosis; increased ratios of cleaved caspase-9/caspase-9, Bax/Bcl-2, cleav ed caspase-8/caspase-8, and cleaved caspase-12/caspase-12; increased expression of cytochrome c and activity of caspase-3; diminished levels of zonula occludens-1, claudin-5, and occludin; and increased levels of MMP-2 and MMP-9. However, hyperoside pretreatment reversed these changes in a dose-dependent manner. Our findings confirm that hyperoside alleviates fibrillar Aβ1-42-induced BBB disruption, thus offering a feasible therapeutic application in Alzheimer's disease.展开更多
As an aging-associated degenerative disease,Alzheimer’s disease is characterized by the deposition of amyloid beta(Aβ),oxidative stress,inflammation,dysfunction and loss of cholinergic neurons.Colla Corii Asini(CCA)...As an aging-associated degenerative disease,Alzheimer’s disease is characterized by the deposition of amyloid beta(Aβ),oxidative stress,inflammation,dysfunction and loss of cholinergic neurons.Colla Corii Asini(CCA)is a traditional Chinese medicine which has been used for feebleness-related diseases and anti-aging.CCA might delay aging-induced degenerative changes in neurons.In the present study,we evaluated antioxidant activity,cytoprotective effects,and Aβremovability of enzyme-digested Colla Corii Asini(CCAD).Oxygen radical absorbance capacity(ORAC)activity assay showed that,as compared to gelatins from the skin of porcine,bovine and cold water fish,CCA exhibited the highest ORAC activity.The ORAC activity of CCA and CCAD was increased gradually by the length of time in storage.Ultrastructure analysis by scanning electron microscopy showed that among CCA manufactured in 2008,2013,2017 and gelatin from cold water fish skin,CCA manufactured in 2008 presented the smoothest surface structure.We further tested the protective effects of CCAD(manufactured in 2008)and enzyme-digested gelatin from cold water fish skin(FGD)on hydrogen peroxide(H2O2)-induced cell death in nerve growth factor-differentiated neuronal-like PC12 cells.Presto blue assay showed that both FGD and CCAD at 0.5 mg/m L increased cell viability in H2O2-treated neuronal-like PC12 cells.The protection of CCAD was significantly superior to that of FGD.Acetylcholinesterase(Ach E)assay showed that both FGD and CCAD inhibited Ach E activity in nerve growth factor-differentiated neuronal-like PC12 cells to 89.1%and 74.5%of that in non-treated cells,respectively.The data suggest that CCAD might be able to increase the neurotransmitter acetylcholine.Although CCAD inhibited Ach E activity in neuronal-like PC12 cells,CCAD prevented H2O2-induced abnormal deterioration of Ach E.ELISA and neprilysin activity assay results indicated that CCAD reduced amyloid beta accumulation and increased neprilysin activity in Aβ1–42-treated neuronal-like PC12 cells,suggesting that CCAD can enhance Aβclearance.Our results suggest that CCA might be useful for preventing and treating Alzheimer’s disease.展开更多
Previous studies have shown that sirtuin 1(SIRT1) reduces the production of neuronal amyloid beta(Aβ) and inhibits the inflammatory response of glial cells, thereby generating a neuroprotective effect against Aβ...Previous studies have shown that sirtuin 1(SIRT1) reduces the production of neuronal amyloid beta(Aβ) and inhibits the inflammatory response of glial cells, thereby generating a neuroprotective effect against Aβ neurotoxicity in animal models of Alzheimer's disease. However, the protective effect of SIRT1 on astrocytes is still under investigation. This study established a time point model for the clearance of Aβ in primary astrocytes. Results showed that 12 hours of culture was sufficient for endocytosis of oligomeric Aβ, and 36 hours sufficient for effective degradation. Immunofluorescence demonstrated that Aβ degradation in primary astrocytes relies on lysosome function. Enzymatic agonists or SIRT1 inhibitors were used to stimulate cells over a concentration gradient. Aβ was co-cultured for 36 hours in medium. Western blot assay results under different conditions revealed that SIRT1 relies on its deacetylase activity to promote intracellular Aβ degradation. The experiment further screened SIRT1 using quantitative proteomics to investigate downstream, differentially expressed proteins in the Aβ degradation pathway and selected the ones related to enzyme activity of SIRT1. Most of the differentially expressed proteins detected are close to the primary astrocyte lysosomal pathway. Immunofluorescence staining demonstrated that SIRT1 relies on its deacetylase activity to upregulate lysosome number in primary astrocytes. Taken together, these findings confirm that SIRT1 relies on its deacetylase activity to upregulate lysosome number, thereby facilitating oligomeric Aβ degradation in primary astrocytes.展开更多
Alzheimer's disease is pathologically defined by accumulation of extracellular amyloid-β(Aβ). Approximately 25 mutations in β-amyloid precursor protein(APP) are pathogenic and cause autosomal dominant Alzheimer...Alzheimer's disease is pathologically defined by accumulation of extracellular amyloid-β(Aβ). Approximately 25 mutations in β-amyloid precursor protein(APP) are pathogenic and cause autosomal dominant Alzheimer's disease. To date, the mechanism underlying the effect of APP mutation on Aβ generation is unclear. Therefore, investigating the mechanism of APP mutation on Alzheimer's disease may help understanding of disease pathogenesis. Thus, APP mutations(A673T, A673 V, E682 K, E693 G, and E693Q) were transiently co-transfected into human embryonic kidney cells. Western blot assay was used to detect expression levels of APP, beta-secretase 1, and presenilin 1 in cells. Enzyme-linked immunosorbent assay was performed to determine Aβ_(1–40) and Aβ_(1–42) levels. Liquid chromatography-tandem mass chromatography was used to examine VVIAT, FLF, ITL, VIV, IAT, VIT, TVI, and VVIA peptide levels. Immunofluorescence staining was performed to measure APP and early endosome antigen 1 immunoreactivity. Our results show that the protective A673 T mutation decreases Aβ_(42)/Aβ_(40) rate by downregulating IAT and upregulating VVIA levels. Pathogenic A673 V, E682 K, and E693 Q mutations promote Aβ_(42)/Aβ_(40) rate by increasing levels of CTF99, Aβ_(42), Aβ_(40), and IAT, and decreasing VVIA levels. Pathogenic E693 G mutation shows no significant change in Aβ_(42)/Aβ_(40) ratio because of inhibition of γ-secretase activity. APP mutations can change location from the cell surface to early endosomes. Our findings confirm that certain APP mutations accelerate Aβ generation by affecting the long Aβ cleavage pathway and increasing Aβ_(42/40) rate, thereby resulting in Alzheimer's disease.展开更多
文摘In the words of the late Sir Colin Blakemore,neurologists have historically sought to infer brain functions in a manner akin to to king a hammer to a computeranalyzing localized anatomical lesions caused by trauma,tumors,or strokes,noting deficits,and inferring what functions certain brain regions may be responsible for.This approach exemplifies a deletion heuristic,where the absence of a specific function reveals insights about the underlying structures or mechanisms responsible for it.By observing what is lost when a particular brain region is damaged,throughout the history of the field,neurologists have pieced together the intricate relationship between anatomy and function.
基金supported by the Nature Science Foundation of Liaoning Province,Nos.2022-MS-211,2021-MS-064,and 2024-MS-048(all to YC).
文摘Alzheimer’s disease,a devastating neurodegenerative disorder,is characterized by progressive cognitive decline,primarily due to amyloid-beta protein deposition and tau protein phosphorylation.Effectively reducing the cytotoxicity of amyloid-beta42 aggregates and tau oligomers may help slow the progression of Alzheimer’s disease.Conventional drugs,such as donepezil,can only alleviate symptoms and are not able to prevent the underlying pathological processes or cognitive decline.Currently,active and passive immunotherapies targeting amyloid-beta and tau have shown some efficacy in mice with asymptomatic Alzheimer’s disease and other transgenic animal models,attracting considerable attention.However,the clinical application of these immunotherapies demonstrated only limited efficacy before the discovery of lecanemab and donanemab.This review first discusses the advancements in the pathogenesis of Alzheimer’s disease and active and passive immunotherapies targeting amyloid-beta and tau proteins.Furthermore,it reviews the advantages and disadvantages of various immunotherapies and considers their future prospects.Although some antibodies have shown promise in patients with mild Alzheimer’s disease,substantial clinical data are still lacking to validate their effectiveness in individuals with moderate Alzheimer’s disease.
基金supported by NIH(R01AG055413),(R01AG085562),(R21AG059134),(R21AG078749),and(S10OD028609)awards(C.R.).NIH Office of the Director,National Institute on Aging.
文摘Alzheimer's disease(AD)is a neurodegenerative disease characterized by a progressive decline in cognitive functions.Given that AD undermines the quality of life for millions and has an extended asymptomatic period,exploring the full AD pathogenesis and seeking the optimal therapeutic solution have become critical and imperative.This allows researchers to intervene,delay,and potentially prevent AD progression.Several clinical imaging methods are utilized routinely to diagnose and monitor AD,such as magnetic resonance imaging(MRI),functional magnetic resonance imaging(fMRI),positron emission tomography(PET),and single photon emission computed tomography(SPECT).Nevertheless,due to their intrinsic drawbacks and restrictions,such as radiation concerns,high cost,long acquisition time,and low spatial resolution,their applications in AD research are limited,especially at the cellular and molecular levels.In contrast,optical microscopic imaging methods overcome these limitations,offering researchers a variety of approaches with distinct advantages to explore AD pathology on diverse models.In this review,we provide a comprehensive overview of commonly utilized optical microscopic imaging techniques in AD research and introduce their contributions to image amyloid beta(Aβ)species.These techniques include fluorescence microscopy(FM),confocal microscopy(CM),two-photon fluorescence microscopy(TPFM),super-resolution microscopy(SRM),expansion microscopy(ExM),and light-sheet fluorescence microscopy(LSFM).In addition,we introduce some related topics,such as the development of near-infrared(NIR)Aβprobes,the Aβplaque hypothesis,and Aβoligomer hypothesis,and the roles of microglia and astrocytes in AD progression.We believe optical microscopic imaging methods continue to play an indispensable role in deciphering the full pathogenesis of AD and advancing therapeutic strategies.
基金supported by a grant from NIH(R01AI132695)to RM。
文摘Pathological and clinical variability in Alzheimer's disease(AD):AD is clinically cha racterized by progressive memory loss and cognitive impairment.From a pathological point of view,the main features of AD are the deposition of amyloid plaques(composed of amyloid-beta,Aβ)and neurofibrillary tangles containing hyperphosphorylated Tau in the brain,accompanied by neu ronal and synaptic loss,neuroinflammation and brain atrophy(Jellinger,2022).Regardless of these common traits,growing evidence shows increased heterogen eity in the brain of AD patients considering both clinical manifestations and pathological features.
文摘In the article titled“Activation of autophagy by Citri Reticulatae Semen extract ameliorates amyloid-beta-induced cell death and cognition deficits in Alzheimer’s disease”published on pages 2467-2479,Issue 11,Volume 19 of Neural Regeneration Research(Tang et al.,2024),there are some errors in selecting the appropriate images in Figure 7 by authors during assembling the images.
基金the National Natural Science Foundation of China,No.81771441 and No.81371213the Natural Science Foundation of Shanghai,No.21ZR1468400.
文摘BACKGROUND Alzheimer’s disease(AD)is a progressive neurodegenerative disorder currently lacking effective therapeutic interventions.Pathological hallmarks of AD include intracellular neurofibrillary tangles(NFTs)and extracellular amyloid beta(Aβ)plaques.Neuroplastin 65(NP65),highly expressed in the brain,has been previously shown to mitigate cognitive impairments and decrease Aβplaques in the AD mouse model,suggesting that NP65 is involved in AD neuropathology.However,direct evidence linking NP65 expression to AD pathogenesis in human brain remains absent.AIM To quantify NP65 isoform expression gradients across distinct neuroanatomical regions in the healthy brain and investigate the alterations of NP65 expression in the AD brain.METHODS Immunohistochemical,immunofluorescent and western blot analyses were used to investigate NP65 expression in 19 postmortem brains(AD=10,controls=9).Double immunostaining with 6E10 and or phosphorylated-microtubule-associated protein tau(AT-8,a marker for NFT)markers was performed to assess NP65 colocalization with Aβplaques and NFTs.RESULTS In controls,NP65 was highly expressed in a wide-range of brain areas.AD cases showed significantly increased NP65 immunoreactivity across multiple brain regions,including the frontal and temporal cortex,hippocampus,and cerebellum,compared to controls.Western blot analysis consistently confirmed significantly elevated NP65 expression in the hippocampus of AD patients relative to controls.Double immunostaining demonstrated partial colocalization of NP65 with NFTs and Aβplaques in AD brain tissue.CONCLUSION Our findings demonstrate a significant increase of NP65 protein,which colocalizes with NFTs and Aβplaques in AD brains,providing direct evidence supporting a critical role of NP65 expression in the neuropathological mechanisms of this disease.
基金Supported by the Autonomous Research Project of SKLCC(2024BWZ003)Strategic Priority Research Program of the Chinese Academy of Sciences(XDA0390401)the Doctoral Research Start-up Funding of Shanxi Institute of Technology(026012).
文摘KIT-5/Beta composite supports were synthesized using an in situ self-assembly hydrothermal method,and NiW/KIT-5/Beta catalysts were prepared by impregnation.A series of characterization techniques were utilized to evaluate the influence of varying hydrothermal synthesis temperatures on the physicochemical properties of both the KIT-5/Beta supports and the resulting catalysts.The catalytic performances of catalysts were evaluated under reaction conditions of 320℃,4 MPa H_(2)pressure,and a weight hourly space velocity(WHSV)of 4.8 h^(-1)for hydrodenitrogenation(HDN)of quinoline.The results indicated that the specific surface area and pore structure of the materials could be effectively regulated by adjusting the hydrothermal synthesis temperature,which in turn influenced the number of active sites on the catalyst.The NiW/KB-125 catalyst,synthesized at 125℃,presented the highest quinoline HDN efficiency(96.8%),which can be attributed to its favorable pore channel structure,greater Brønsted acid number,higher degree of metal sulfidation(80.12%)and appropriate metal-support interaction(MSI).
基金funded by the Russian Science Foundation(grant No.23-74-10092)(to AIS)。
文摘Currently,our understanding of the pathogenesis of major neurodegenerative disorders,such as Alzheimer's,Parkinson's,and Huntington's diseases,is largely shaped by the amyloid cascade hypothesis.Pa rticularly,this hypothesis posits that in Alzheimer's disease,the aggregation of amyloid-beta peptide initiates a series of pathological processes leading to neuronal dysfunction and death(Zhang et al.,2024).
文摘Amyloid-β(Aβ)and tau,the two hallmark proteins associated with Alzheimer’s disease(AD),exhibit distinct toxic effects but also interact synergistically within the disease pathology.The prevailing theory in AD pathology-the amyloid cascade hypothesis-highlights the pivotal role of increased processing of the amyloid precursor protein(APP).Initially cleaved by the majorβ-secretase(β-amyloid cleaving enzyme-1,BACE1)in the brain,then undergoes further cleavage by theγ-secretase complex,resulting in the production of Aβ_(40-42)and a set of intracellular C-terminal peptides known as Aβand APP intracellular domain(β-AICDs)and soluble amyloid precursor proteinβ(sAPPβ)(Orobets and Karamyshev,2023).
基金funded by the National Centre for the Replacement Refinement&Reduction of Animals in Research(NC3R:Grant#NC/L001152/1)the Macular Society,UK,National Eye Research Centrethe Gift of Sight Appeal
文摘e-related macular degeneration (AMD) causes irreversible loss of central vision for which there is no effective treatment. Incipient pathology is thought to occur in the retina for many years before AMD manifests from midlife onwards to affect a large proportion of the elderly. Although genetic as well as non-genetic/environmental risks are recognized, its complex aetiology makes it difficult to identify susceptibility, or indeed what type of AMD develops or how quickly it progresses in different individuals. Here we summarize the literature describing how the Alzheimer's-linked amyloid beta (Aβ) group of misfolding proteins accumulate in the retina. The discovery of this key driver of Alzheimer's disease in the senescent retina was unexpected and surprising, enabling an altogether different perspective of AMD. We argue that Aβ fundamentally differs from other substances which accumulate in the ageing retina, and discuss our latest findings from a mouse model in which physiological amounts of Aβ were subretinally-injected to recapitulate salient features of early AMD within a short period. Our discoveries as well as those of others suggest the pattern of Aβ accumulation and pathology in donor aged/AMD tissues are closely reproduced in mice, including late-stage AMD phenotypes, which makes them highly attractive to study dynamic aspects of Aβ-mediated retinopathy. Furthermore, we discuss our findings revealing how Aβ behaves at single-cell resolution, and consider the long-term implications for neuroretinal function. We propose Aβ as a key element in switching to a diseased retinal phenotype, which is now being used as a biomarker for latestage AMD.
基金financially supported by the National Natural Science Foundation of China,No.81473201the Natural Science Foundation of Educational Commission of Guizhou Province of China,No.2010043+1 种基金the Science and Technology Foundation of Guizhou Province of China,No.JZ[2014]2016the Modernization of Traditional Chinese Medicine Project of Guizhou Province of China,No.[2011]5086
文摘Dendrobium nobile Lindl.alkaloids(DNLA),the active ingredients of a traditional Chinese medicine Dendrobium,have been shown to have anti-oxidative effects,anti-inflammatory action,and protective effect on neurons against oxygen-glucose deprivation.However,it is not clear whether DNLA reduces amyloid-beta(Aβ)-induced neuronal injury.In this study,cortical neurons were treated with DNLA at different concentrations(0.025,0.25,and 2.5 mg/L)for 24 hours,followed by administration of Aβ(25-35)(10μM).Aβ(25-35) treatments increased cell injury as determined by the leakage of lactate dehydrogenase,which was accompanied by chromatin condensation and mitochondrial tumefaction.The damage caused by Aβ(25-35) on these cellular properties was markedly attenuated when cells were pretreated with DNLA.Treatment with Aβ(25-35)down-regulated the expressions of postsynaptic density-95 mRNA and decreased the protein expression of synaptophysin and postsynaptic density-95,all changes were significantly reduced by pretreatment of cells with DNLA.These findings suggest that DNLA reduces the cytotoxicity induced by Aβ(25-35) in rat primary cultured neurons.The protective mechanism that DNLA confers on the synaptic integrity of cultured neurons might be mediated,at least in part,through the upregulation of neurogenesis related proteins synaptophysin and postsynaptic density-95.
基金Shanxi Provincial Special Fund for the Transformation of Scientific and Technological Achievements,No.201704D13111584(to JHG)。
文摘Neurovascular dysfunction,as an integral part of Alzheimer's disease,may have an important influence on the onset and progression of chronic neurodegenerative processes.The bloodbrain barrier(BBB)pathway is one of the main pathways that mediates the clearance of amyloidbeta(Aβ)in the brain parenchyma.A large number of studies have shown that receptors and ATPbinding cassette transporte rs expressed on endothelial cells play an important role in Aβtransport across the BBB,but the specific mechanism is not clear.In this review,we summarize the possible mechanisms of Aβproduction and clearance,and in particular the relationship between Aβand brain capillary endothelial cells.Aβis produced by abnormal cleavage of the amyloid precursor protein via amyloidogenic processing under pathological conditions.Dys regulation of Aβclearance is considered to be the main reason for the massive accumulation of Aβin the brain parenchyma.Several pathways mediating Aβclearance from the brain into the periphery have been identified,including the BBB pathway,the blood-cerebros pinal fluid barrier and arachnoid granule pathway,and the lymphoidrelated pathway.Brain ca pilla ry endothelial cells are the key components of Aβclearance mediated by BBB.Receptors(such as LRP1,RAGE,and FcRn)and ATP-binding cassette transporters(such as P-gp,ABCA1,and ABCC1)expressed on endothelial cells play a critical role in Aβtranscytosis across the BBB.The toxic effects of Aβcan induce dysregulation of receptor and transpo rter expression on endothelial cells.Excessive Aβexerts potent detrimental cerebrovascular effects by promoting oxidative stress,inducing chronic inflammation,and impairing endothelial structure and functions.All of these are main causes for the reduction in Aβclearance across the BBB and the accumulation of Aβin the brain parenchyma.Therefo re,studies on the intera ctions between Aβand brain capillary endothelial cells,including their receptors and transporters,studies on inhibition of the toxic effects of Aβon endothelial cells,and studies on promoting the ability of endothelial cells to mediate Aβclearance may provide new therapeutic strategies for Aβclearance in Alzheimer's disease.
基金Project supported by the NSFC (20831003, 90813001, 20903086)Funds from CAS
文摘Rare earth elements have unique physical, magnetic, luminescent and catalytic properties. They have been successfully used as medicine and probes in luminescent resonance energy transfer (LRET) for bioassays, as well as reagents for diagnosis in magnetic resonance imaging (MRI). In this progress report, we will focus on recent progress on how rare earth amino complexes bind to DNA and change DNA structure, especially on DNA B-Z transition induced by rare earth amino acid complex and its potential impact on Alzheimer’s disease (AD).
基金supported by a grant from Projects of High-tech Industrialization of Guangdong Province of China,No.2011B010500004a grant from National Financial Major Project of China
文摘Amyloid-beta peptide is the main component of amyloid plaques, which are found in Alzhei- mer's disease. The generation and deposition of amyloid-beta is one of the crucial factors for the onset and progression of Alzheimer's disease. Lipid rafts are glycolipid-rich liquid domains of the plasma membrane, where certain types of protein tend to aggregate and intercalate. Lipid rafts are involved in the generation of amyloid-beta oligomers and the formation of amyloid-beta peptides. In this paper, we review the mechanism by which lipid rafts disturb the aberrant deg- radative autophagic-lysosomal pathway of amyloid-beta, which plays an important role in the pathological process of Alzheimer's disease. Moreover, we describe this mechanism from the view of the Two-system Theory of fasciology and thus, suggest that lipid rafts may be a new target of Alzheimer's disease treatment.
基金financially supported by the National Natural Science Foundation of China,No.81573771the Natural Science Foundation of Jiangsu Province of China,No.BK20151599
文摘Mounting evidence indicates that amyloid β protein(Aβ) exerts neurotoxicity by disrupting the blood-brain barrier(BBB) in Alzheimer's disease. Hyperoside has neuroprotective effects both in vitro and in vivo against Aβ. Our previous study found that hyperoside suppressed Aβ1-42-induced leakage of the BBB, however, the mechanism remains unclear. In this study, bEnd.3 cells were pretreated with 50, 200, or 500 μM hyperoside for 2 hours, and then exposed to Aβ1-42 for 24 hours. Cell viability was determined using 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide assay. Flow cytometry and terminal deoxynucleotidyl transferase-mediated d UTP nick-end labeling assay were used to analyze cell apoptosis. Western blot assay was carried out to analyze expression levels of Bax, Bcl-2, cytochrome c, caspase-3, caspse-8, caspase-9, caspase-12, occludin, claudin-5, zonula occludens-1, matrix metalloproteinase-2(MMP-2), and MMP-9. Exposure to Aβ1-42 alone remarkably induced bEnd.3 cell apoptosis; increased ratios of cleaved caspase-9/caspase-9, Bax/Bcl-2, cleav ed caspase-8/caspase-8, and cleaved caspase-12/caspase-12; increased expression of cytochrome c and activity of caspase-3; diminished levels of zonula occludens-1, claudin-5, and occludin; and increased levels of MMP-2 and MMP-9. However, hyperoside pretreatment reversed these changes in a dose-dependent manner. Our findings confirm that hyperoside alleviates fibrillar Aβ1-42-induced BBB disruption, thus offering a feasible therapeutic application in Alzheimer's disease.
基金supported in part by the Japan Society for the Promotion of Science(JSPS)Grant-in-Aid for Scientific Research,No.17K11813(to LX)Tai Shan Industrial Experts Program of China No.TSCY20170233(to FL)。
文摘As an aging-associated degenerative disease,Alzheimer’s disease is characterized by the deposition of amyloid beta(Aβ),oxidative stress,inflammation,dysfunction and loss of cholinergic neurons.Colla Corii Asini(CCA)is a traditional Chinese medicine which has been used for feebleness-related diseases and anti-aging.CCA might delay aging-induced degenerative changes in neurons.In the present study,we evaluated antioxidant activity,cytoprotective effects,and Aβremovability of enzyme-digested Colla Corii Asini(CCAD).Oxygen radical absorbance capacity(ORAC)activity assay showed that,as compared to gelatins from the skin of porcine,bovine and cold water fish,CCA exhibited the highest ORAC activity.The ORAC activity of CCA and CCAD was increased gradually by the length of time in storage.Ultrastructure analysis by scanning electron microscopy showed that among CCA manufactured in 2008,2013,2017 and gelatin from cold water fish skin,CCA manufactured in 2008 presented the smoothest surface structure.We further tested the protective effects of CCAD(manufactured in 2008)and enzyme-digested gelatin from cold water fish skin(FGD)on hydrogen peroxide(H2O2)-induced cell death in nerve growth factor-differentiated neuronal-like PC12 cells.Presto blue assay showed that both FGD and CCAD at 0.5 mg/m L increased cell viability in H2O2-treated neuronal-like PC12 cells.The protection of CCAD was significantly superior to that of FGD.Acetylcholinesterase(Ach E)assay showed that both FGD and CCAD inhibited Ach E activity in nerve growth factor-differentiated neuronal-like PC12 cells to 89.1%and 74.5%of that in non-treated cells,respectively.The data suggest that CCAD might be able to increase the neurotransmitter acetylcholine.Although CCAD inhibited Ach E activity in neuronal-like PC12 cells,CCAD prevented H2O2-induced abnormal deterioration of Ach E.ELISA and neprilysin activity assay results indicated that CCAD reduced amyloid beta accumulation and increased neprilysin activity in Aβ1–42-treated neuronal-like PC12 cells,suggesting that CCAD can enhance Aβclearance.Our results suggest that CCA might be useful for preventing and treating Alzheimer’s disease.
基金supported by the National Natural Science Foundation of China,No.31670832,31470807,31270872a grant from the National Key Research and Development Program of China,No.2016YFA0500301a grant from the State Key Laboratory of Protein and Plant Gene Research,College of Life Sciences,Peking University,China
文摘Previous studies have shown that sirtuin 1(SIRT1) reduces the production of neuronal amyloid beta(Aβ) and inhibits the inflammatory response of glial cells, thereby generating a neuroprotective effect against Aβ neurotoxicity in animal models of Alzheimer's disease. However, the protective effect of SIRT1 on astrocytes is still under investigation. This study established a time point model for the clearance of Aβ in primary astrocytes. Results showed that 12 hours of culture was sufficient for endocytosis of oligomeric Aβ, and 36 hours sufficient for effective degradation. Immunofluorescence demonstrated that Aβ degradation in primary astrocytes relies on lysosome function. Enzymatic agonists or SIRT1 inhibitors were used to stimulate cells over a concentration gradient. Aβ was co-cultured for 36 hours in medium. Western blot assay results under different conditions revealed that SIRT1 relies on its deacetylase activity to promote intracellular Aβ degradation. The experiment further screened SIRT1 using quantitative proteomics to investigate downstream, differentially expressed proteins in the Aβ degradation pathway and selected the ones related to enzyme activity of SIRT1. Most of the differentially expressed proteins detected are close to the primary astrocyte lysosomal pathway. Immunofluorescence staining demonstrated that SIRT1 relies on its deacetylase activity to upregulate lysosome number in primary astrocytes. Taken together, these findings confirm that SIRT1 relies on its deacetylase activity to upregulate lysosome number, thereby facilitating oligomeric Aβ degradation in primary astrocytes.
基金funded by the National Natural Science Foundation of China,No.81671268(to HQ)partially supported by a grant from the Ministry of Science and Technology of China,No.2013YQ03059514(to HQ)a grant from Key Laboratory for Neurodegenerative Disease of Ministry of Education of China,No.2015SJBX05(to HQ),2015SJZS01(to HQ)
文摘Alzheimer's disease is pathologically defined by accumulation of extracellular amyloid-β(Aβ). Approximately 25 mutations in β-amyloid precursor protein(APP) are pathogenic and cause autosomal dominant Alzheimer's disease. To date, the mechanism underlying the effect of APP mutation on Aβ generation is unclear. Therefore, investigating the mechanism of APP mutation on Alzheimer's disease may help understanding of disease pathogenesis. Thus, APP mutations(A673T, A673 V, E682 K, E693 G, and E693Q) were transiently co-transfected into human embryonic kidney cells. Western blot assay was used to detect expression levels of APP, beta-secretase 1, and presenilin 1 in cells. Enzyme-linked immunosorbent assay was performed to determine Aβ_(1–40) and Aβ_(1–42) levels. Liquid chromatography-tandem mass chromatography was used to examine VVIAT, FLF, ITL, VIV, IAT, VIT, TVI, and VVIA peptide levels. Immunofluorescence staining was performed to measure APP and early endosome antigen 1 immunoreactivity. Our results show that the protective A673 T mutation decreases Aβ_(42)/Aβ_(40) rate by downregulating IAT and upregulating VVIA levels. Pathogenic A673 V, E682 K, and E693 Q mutations promote Aβ_(42)/Aβ_(40) rate by increasing levels of CTF99, Aβ_(42), Aβ_(40), and IAT, and decreasing VVIA levels. Pathogenic E693 G mutation shows no significant change in Aβ_(42)/Aβ_(40) ratio because of inhibition of γ-secretase activity. APP mutations can change location from the cell surface to early endosomes. Our findings confirm that certain APP mutations accelerate Aβ generation by affecting the long Aβ cleavage pathway and increasing Aβ_(42/40) rate, thereby resulting in Alzheimer's disease.