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1.
Cell Death Discov ; 10(1): 167, 2024 Apr 08.
Article in English | MEDLINE | ID: mdl-38589400

ABSTRACT

The neurotoxic α-synuclein (α-syn) oligomers play an important role in the occurrence and development of Parkinson's disease (PD), but the factors affecting α-syn generation and neurotoxicity remain unclear. We here first found that thrombomodulin (TM) significantly decreased in the plasma of PD patients and brains of A53T α-syn mice, and the increased TM in primary neurons reduced α-syn generation by inhibiting transcription factor p-c-jun production through Erk1/2 signaling pathway. Moreover, TM decreased α-syn neurotoxicity by reducing the levels of oxidative stress and inhibiting PAR1-p53-Bax signaling pathway. In contrast, TM downregulation increased the expression and neurotoxicity of α-syn in primary neurons. When TM plasmids were specifically delivered to neurons in the brains of A53T α-syn mice by adeno-associated virus (AAV), TM significantly reduced α-syn expression and deposition, and ameliorated the neuronal apoptosis, oxidative stress, gliosis and motor deficits in the mouse models, whereas TM knockdown exacerbated these neuropathology and motor dysfunction. Our present findings demonstrate that TM plays a neuroprotective role in PD pathology and symptoms, and it could be a novel therapeutic target in efforts to combat PD. Schematic representation of signaling pathways of TM involved in the expression and neurotoxicity of α-syn. A TM decreased RAGE, and resulting in the lowered production of p-Erk1/2 and p-c-Jun, and finally reduce α-syn generation. α-syn oligomers which formed from monomers increase the expression of p-p38, p53, C-caspase9, C-caspase3 and Bax, decrease the level of Bcl-2, cause mitochondrial damage and lead to oxidative stress, thus inducing neuronal apoptosis. TM can reduce intracellular oxidative stress and inhibit p53-Bax signaling by activating APC and PAR-1. B The binding of α-syn oligomers to TLR4 may induce the expression of IL-1ß, which is subsequently secreted into the extracellular space. This secreted IL-1ß then binds to its receptor, prompting p65 to translocate from the cytoplasm into the nucleus. This translocation downregulates the expression of KLF2, ultimately leading to the suppression of TM expression. By Figdraw.

2.
Acta Neuropathol Commun ; 12(1): 66, 2024 Apr 23.
Article in English | MEDLINE | ID: mdl-38654316

ABSTRACT

The elderly frequently present impaired blood-brain barrier which is closely associated with various neurodegenerative diseases. However, how the albumin, the most abundant protein in the plasma, leaking through the disrupted BBB, contributes to the neuropathology remains poorly understood. We here demonstrated that mouse serum albumin-activated microglia induced astrocytes to A1 phenotype to remarkably increase levels of Elovl1, an astrocytic synthase for very long-chain saturated fatty acids, significantly promoting VLSFAs secretion and causing neuronal lippoapoptosis through endoplasmic reticulum stress response pathway. Moreover, MSA-activated microglia triggered remarkable tau phosphorylation at multiple sites through NLRP3 inflammasome pathway. Intracerebroventricular injection of MSA into the brains of C57BL/6J mice to a similar concentration as in patient brains induced neuronal apoptosis, neuroinflammation, increased tau phosphorylation, and decreased the spatial learning and memory abilities, while Elovl1 knockdown significantly prevented the deleterious effect of MSA. Overall, our study here revealed that MSA induced tau phosphorylation and neuron apoptosis based on MSA-activated microglia and astrocytes, respectively, showing the critical roles of MSA in initiating the occurrence of tauopathies and cognitive decline, and providing potential therapeutic targets for MSA-induced neuropathology in multiple neurodegenerative disorders.


Subject(s)
Apoptosis , Mice, Inbred C57BL , Neurons , Serum Albumin , Tauopathies , Animals , Humans , Male , Mice , Apoptosis/drug effects , Apoptosis/physiology , Astrocytes/metabolism , Astrocytes/pathology , Astrocytes/drug effects , Fatty Acid Elongases/metabolism , Microglia/metabolism , Microglia/drug effects , Microglia/pathology , Neurons/metabolism , Neurons/pathology , Neurons/drug effects , Serum Albumin/metabolism , Serum Albumin/pharmacology , tau Proteins/metabolism , Tauopathies/pathology , Tauopathies/metabolism
3.
Eur J Pharmacol ; 970: 176491, 2024 May 05.
Article in English | MEDLINE | ID: mdl-38503399

ABSTRACT

Alzheimer's disease (AD) is a progressive neurodegenerative disease with the hallmark of aggregation of beta-amyloid (Aß) into extracellular fibrillar deposition. Accumulating evidence suggests that soluble toxic Aß oligomers exert diverse roles in neuronal cell death, oxidative stress, neuroinflammation, and the eventual pathogenesis of AD. Aß is derived from the sequential cleavage of amyloid-ß precursor protein (APP) by ß-secretase (BACE1) and γ-secretase. The current effect of single targeting is not ideal for the treatment of AD. Therefore, developing multipotent agents with multiple properties, including anti-Aß generation and anti-Aß aggregation, is attracting more attention for AD treatment. Previous studies indicated that Quercetin was able to attenuate the effects of several pathogenetic factors in AD. Here, we showed that naturally synthesized Quercetin-3-O-glc-1-3-rham-1-6-glucoside (YCC31) could inhibit Aß production by reducing ß-secretase activity. Further investigations indicated that YCC31 could suppress toxic Aß oligomer formation by directly binding to Aß. Moreover, YCC31 could attenuate Aß-mediated neuronal death, ROS and NO production, and pro-inflammatory cytokines release. Taken together, YCC31 targeting multiple pathogenetic factors deserves further investigation for drug development of AD.


Subject(s)
Alzheimer Disease , Neurodegenerative Diseases , Humans , Amyloid Precursor Protein Secretases/metabolism , Quercetin/pharmacology , Quercetin/therapeutic use , Cytokines , Aspartic Acid Endopeptidases/metabolism , Aspartic Acid Endopeptidases/therapeutic use , Alzheimer Disease/drug therapy , Amyloid beta-Peptides/metabolism , Amyloid beta-Protein Precursor/metabolism , Glucosides/therapeutic use
4.
Angew Chem Int Ed Engl ; 63(10): e202318530, 2024 Mar 04.
Article in English | MEDLINE | ID: mdl-38196070

ABSTRACT

Dendritic cell (DC) maturation and antigen presentation are key factors for successful vaccine-based cancer immunotherapy. This study developed manganese-based layered double hydroxide (Mn-LDH) nanoparticles as a self-adjuvanted vaccine carrier that not only promoted DC maturation through synergistically depleting endogenous glutathione (GSH) and activating STING signaling pathway, but also facilitated the delivery of model antigen ovalbumin (OVA) into lymph nodes and subsequent antigen presentation in DCs. Significant therapeutic-prophylactic efficacy of the OVA-loaded Mn-LDH (OVA/Mn-LDH) nanovaccine was determined by the tumor growth inhibition in the mice bearing B16-OVA tumor. Our results showed that the OVA/Mn-LDH nanoparticles could be a potent delivery system for cancer vaccine development without the need of adjuvant. Therefore, the combination of GSH exhaustion and STING pathway activation might be an advisable approach for promoting DC maturation and antigen presentation, finally improving cancer vaccine efficacy.


Subject(s)
Cancer Vaccines , Nanoparticles , Neoplasms , Mice , Animals , Vaccine Efficacy , Neoplasms/pathology , Immunotherapy/methods , Adjuvants, Immunologic/pharmacology , Glutathione , Dendritic Cells , Mice, Inbred C57BL , Ovalbumin
5.
MedComm (2020) ; 4(5): e371, 2023 Oct.
Article in English | MEDLINE | ID: mdl-37750090

ABSTRACT

Aged male patients are more vulnerable to severe or critical symptoms of COVID-19, but the underlying mechanism remains elusive. In this study, we analyzed previously published scRNA-seq data from a large cohort of COVID-19 patients, castrated and regenerated mice, and bulk RNA-seq of a RNAi library of 400 genes, and revealed that both immunity and OXPHOS displayed cell-type-, sex-, and age-related variation in the severe or critical COVID-19 patients during disease progression, with a more prominent increase in immunity and decrease in OXPHOS in myeloid cells in the males relative to the females (60-69 years old). Male severe or critical patients above 70 years old were an exception in that the compromised negative correlation between OXPHOS and immunity in these patients was associated with its disordered transcriptional regulation. Finally, the expression levels of OXPHOS and androgens were revealed to be positively correlated, and the responses of macrophages to android fluctuation were more striking than other types of detected immune cells in the castrated mice model. Therefore, the interplay of OXPHOS and immunity displayed a cell-type-specific, age-related, and sex-biased pattern, and the underlying potential regulatory role of the hormonal milieu should not be neglected.

6.
Cell Rep ; 42(6): 112624, 2023 06 27.
Article in English | MEDLINE | ID: mdl-37302068

ABSTRACT

Amyloid-ß (Aß) plays an important role in the neuropathology of Alzheimer's disease (AD), but some factors promoting Aß generation and Aß oligomer (Aßo) neurotoxicity remain unclear. We here find that the levels of ArhGAP11A, a Ras homology GTPase-activating protein, significantly increase in patients with AD and amyloid precursor protein (APP)/presenilin-1 (PS1) mice. Reducing the ArhGAP11A level in neurons not only inhibits Aß generation by decreasing the expression of APP, PS1, and ß-secretase (BACE1) through the RhoA/ROCK/Erk signaling pathway but also reduces Aßo neurotoxicity by decreasing the expressions of apoptosis-related p53 target genes. In APP/PS1 mice, specific reduction of the ArhGAP11A level in neurons significantly reduces Aß production and plaque deposition and ameliorates neuronal damage, neuroinflammation, and cognitive deficits. Moreover, Aßos enhance ArhGAP11A expression in neurons by activating E2F1, which thus forms a deleterious cycle. Our results demonstrate that ArhGAP11A may be involved in AD pathogenesis and that decreasing ArhGAP11A expression may be a promising therapeutic strategy for AD treatment.


Subject(s)
Alzheimer Disease , GTPase-Activating Proteins , Animals , Mice , Alzheimer Disease/metabolism , Amyloid beta-Peptides/metabolism , Amyloid beta-Protein Precursor/metabolism , Amyloid Precursor Protein Secretases/metabolism , Aspartic Acid Endopeptidases/metabolism , Disease Models, Animal , Mice, Transgenic , Presenilin-1/metabolism , GTPase-Activating Proteins/metabolism
7.
Signal Transduct Target Ther ; 8(1): 30, 2023 01 25.
Article in English | MEDLINE | ID: mdl-36693826

ABSTRACT

Passive immunotherapy is one of the most promising interventions for Alzheimer's disease (AD). However, almost all immune-modulating strategies fail in clinical trials with unclear causes although they attenuate neuropathology and cognitive deficits in AD animal models. Here, we showed that Aß-targeting antibodies including their lgG1 and lgG4 subtypes induced microglial engulfment of neuronal synapses by activating CR3 or FcγRIIb via the complex of Aß, antibody, and complement. Notably, anti-Aß antibodies without Fc fragment, or with blockage of CR3 or FcγRIIb, did not exert these adverse effects. Consistently, Aß-targeting antibodies, but not their Fab fragments, significantly induced acute microglial synapse removal and rapidly exacerbated cognitive deficits and neuroinflammation in APP/PS1 mice post-treatment, whereas the memory impairments in mice were gradually rescued thereafter. Since the recovery rate of synapses in humans is much lower than that in mice, our findings may clarify the variances in the preclinical and clinical studies assessing AD immunotherapies. Therefore, Aß-targeting antibodies lack of Fc fragment, or with reduced Fc effector function, may not induce microglial synaptic pruning, providing a safer and more efficient therapeutic alternative for passive immunotherapy for AD.


Subject(s)
Alzheimer Disease , Cognitive Dysfunction , Mice , Humans , Animals , Alzheimer Disease/pathology , Amyloid beta-Peptides , Cognitive Dysfunction/pathology , Synapses/pathology , Antibodies/therapeutic use , Cognition
8.
J Neuroinflammation ; 18(1): 131, 2021 Jun 11.
Article in English | MEDLINE | ID: mdl-34116706

ABSTRACT

BACKGROUND: Tau pathology is a hallmark of Alzheimer's disease (AD) and other tauopathies. During disease progression, abnormally phosphorylated forms of tau aggregate and accumulate into neurofibrillary tangles, leading to synapse loss, neuroinflammation, and neurodegeneration. Thus, targeting of tau pathology is expected to be a promising strategy for AD treatment. METHODS: The effect of rutin on tau aggregation was detected by thioflavin T fluorescence and transmission electron microscope imaging. The effect of rutin on tau oligomer-induced cytotoxicity was assessed by MTT assay. The effect of rutin on tau oligomer-mediated the production of IL-1ß and TNF-α in vitro was measured by ELISA. The uptake of extracellular tau by microglia was determined by immunocytochemistry. Six-month-old male Tau-P301S mice were treated with rutin or vehicle by oral administration daily for 30 days. The cognitive performance was determined using the Morris water maze test, Y-maze test, and novel object recognition test. The levels of pathological tau, gliosis, NF-kB activation, proinflammatory cytokines such as IL-1ß and TNF-α, and synaptic proteins including synaptophysin and PSD95 in the brains of the mice were evaluated by immunolabeling, immunoblotting, or ELISA. RESULTS: We showed that rutin, a natural flavonoid glycoside, inhibited tau aggregation and tau oligomer-induced cytotoxicity, lowered the production of proinflammatory cytokines, protected neuronal morphology from toxic tau oligomers, and promoted microglial uptake of extracellular tau oligomers in vitro. When applied to Tau-P301S mouse model of tauopathy, rutin reduced pathological tau levels, regulated tau hyperphosphorylation by increasing PP2A level, suppressed gliosis and neuroinflammation by downregulating NF-kB pathway, prevented microglial synapse engulfment, and rescued synapse loss in mouse brains, resulting in a significant improvement of cognition. CONCLUSION: In combination with the previously reported therapeutic effects of rutin on Aß pathology, rutin is a promising drug candidate for AD treatment based its combinatorial targeting of tau and Aß.


Subject(s)
Alzheimer Disease/drug therapy , Alzheimer Disease/prevention & control , Neuroinflammatory Diseases/drug therapy , Neuroinflammatory Diseases/prevention & control , Rutin/pharmacology , Rutin/therapeutic use , tau Proteins/antagonists & inhibitors , Alzheimer Disease/immunology , Alzheimer Disease/pathology , Animals , Brain/metabolism , Brain/pathology , Cell Culture Techniques , Disease Models, Animal , Humans , Male , Maze Learning , Mice , Mice, Transgenic , Microglia/drug effects , Microglia/immunology , Microglia/metabolism , Microscopy, Electron, Transmission , Neuroinflammatory Diseases/immunology , Neuroinflammatory Diseases/pathology , Rutin/administration & dosage , Signal Transduction , Synapses/drug effects , Synapses/metabolism , tau Proteins/genetics , tau Proteins/metabolism
9.
Nanoscale ; 13(16): 7533-7549, 2021 Apr 30.
Article in English | MEDLINE | ID: mdl-33876812

ABSTRACT

Layered double hydroxide (LDH) is a 'sandwich'-like two-dimensional clay material that has been systematically investigated for biomedical application in the past two decades. LDH is an alum-similar adjuvant, which has a well-defined layered crystal structure and exhibits high adjuvanticity. The unique structure of LDH includes positively charged layers composed of divalent and trivalent cations and anion-exchangeable interlayer galleries. Among the many variants of LDH, MgAl-LDH (the cationic ions are Mg2+ and Al3+) has the highest affinity to antigens, bioadjuvants and drug molecules, and exhibits superior biosafety. Past research studies indicate that MgAl-LDH can simultaneously load antigens, bioadjuvants and molecular drugs to amplify the strength of immune responses, and induce broad-spectrum immune responses. Moreover, the size and dispersity of MgAl-LDH in biological environments can be well controlled to actively deliver antigens to the immune system, realizing the rapid induction and maintenance of durable immune responses. Furthermore, the functionalization of MgAl-LDH nanoadjuvants enables it to capture antigens in situ and induce personalized immune responses, thereby more effectively overcoming complex diseases. In this review, we comprehensively summarize the development and application of MgAl-LDH nanoparticles as a vaccine adjuvant, demonstrating that MgAl-LDH is the most potential adjuvant for clinical application.


Subject(s)
Hydroxides , Nanoparticles , Aluminum Hydroxide , Antigens , Clay
10.
Cell Rep ; 34(4): 108666, 2021 01 26.
Article in English | MEDLINE | ID: mdl-33503420

ABSTRACT

Although vaccines against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) are under development, the antigen epitopes on the virus and their immunogenicity are poorly understood. Here, we simulate the 3D structures and predict the B cell epitopes on the spike (S), envelope (E), membrane (M), and nucleocapsid (N) proteins of SARS-CoV-2 using structure-based approaches and validate epitope immunogenicity by immunizing mice. Almost all 33 predicted epitopes effectively induce antibody production, six of these are immunodominant epitopes in individuals, and 23 are conserved within SARS-CoV-2, SARS-CoV, and bat coronavirus RaTG13. We find that the immunodominant epitopes of individuals with domestic (China) SARS-CoV-2 are different from those of individuals with imported (Europe) SARS-CoV-2, which may be caused by mutations on the S (G614D) and N proteins. Importantly, we find several epitopes on the S protein that elicit neutralizing antibodies against D614 and G614 SARS-CoV-2, which can contribute to vaccine design against coronaviruses.


Subject(s)
Coronavirus Nucleocapsid Proteins/immunology , Epitopes, B-Lymphocyte/immunology , SARS-CoV-2/immunology , Spike Glycoprotein, Coronavirus/immunology , Viral Matrix Proteins/immunology , Viroporin Proteins/immunology , Adolescent , Adult , Aged , Animals , Antibodies, Neutralizing/immunology , Antibodies, Viral/immunology , Antigens, Viral/immunology , COVID-19/immunology , COVID-19/therapy , COVID-19 Vaccines/immunology , Child , Epitopes, B-Lymphocyte/metabolism , Female , Humans , Male , Mice , Mice, Inbred BALB C , Middle Aged , Young Adult
11.
Int J Mol Sci ; 21(22)2020 Nov 17.
Article in English | MEDLINE | ID: mdl-33212758

ABSTRACT

α-synuclein (α-syn) is a protein associated with the pathogenesis of Parkinson's disease (PD), the second most common neurodegeneration disease with no effective treatment. However, how α-syn drives the pathology of PD remains elusive. Recent studies suggest that α-syn oligomers are the primary cause of neurotoxicity and play a critical role in PD. In this review, we discuss the process of α-syn oligomers formation and the current understanding of the structures of oligomers. We also describe seed and propagation effects of oligomeric forms of α-syn. Then, we summarize the mechanism by which α-syn oligomers exert neurotoxicity and promote neurodegeneration, including mitochondrial dysfunction, endoplasmic reticulum stress, proteostasis dysregulation, synaptic impairment, cell apoptosis and neuroinflammation. Finally, we investigate treatment regimens targeting α-syn oligomers at present. Further research is needed to understand the structure and toxicity mechanism of different types of oligomers, so as to provide theoretical basis for the treatment of PD.


Subject(s)
Parkinson Disease/metabolism , Protein Multimerization , alpha-Synuclein/metabolism , Animals , Apoptosis , Endoplasmic Reticulum Stress , Humans , Inflammation/metabolism , Inflammation/pathology , Mitochondria/metabolism , Mitochondria/pathology , Parkinson Disease/pathology , Parkinson Disease/therapy , Proteostasis
12.
J Nanobiotechnology ; 18(1): 160, 2020 Nov 07.
Article in English | MEDLINE | ID: mdl-33160377

ABSTRACT

BACKGROUND: Alzheimer's disease (AD) is a progressive neurodegenerative disorder. No disease-modifying strategy to prevent or delay AD progression currently exists. Aß oligomers (AßOs), rather than monomers or fibrils, are considered as the primary neurotoxic species. Therapeutic approaches that direct against AßOs and promote Aß clearance may have great value for AD treatment. RESULTS: We here reported a multifunctional superparamagnetic iron oxide nanoparticle conjugated with Aß oligomer-specific scFv antibody W20 and class A scavenger receptor activator XD4 (W20/XD4-SPIONs). Besides the diagnostic value, W20/XD4-SPIONs retained the anti-Aß properties of W20 and XD4 by inhibiting Aß aggregation, attenuating AßO-induced cytotoxicity and increasing microglial phagocytosis of Aß. When applied to APP/PS1 mice, W20/XD4-SPIONs significantly rescued cognitive deficits and alleviated neuropathology of AD mice. CONCLUSION: These results suggest that W20/XD4-SPIONs show therapeutic benefits for AD. In combination with the early diagnostic property, W20/XD4-SPIONs present as a promising agent for early-stage AD diagnosis and intervention.


Subject(s)
Alzheimer Disease/therapy , Magnetic Iron Oxide Nanoparticles/chemistry , Receptors, Scavenger/chemistry , Single-Chain Antibodies/chemistry , Alzheimer Disease/diagnosis , Amyloid , Amyloid beta-Peptides/pharmacology , Animals , Brain/pathology , Cytokines , Kinetics , Male , Mice , Mice, Transgenic , Microglia , Peptide Fragments/pharmacology , Phagocytosis
13.
Int J Nanomedicine ; 15: 4919-4932, 2020.
Article in English | MEDLINE | ID: mdl-32764925

ABSTRACT

BACKGROUND: Alzheimer's disease (AD) is a progressive neurodegenerative disorder and the most common cause of dementia. Diagnosing AD before symptoms arise will facilitate earlier intervention. The early diagnostic approaches are thus urgently needed. METHODS: The multifunctional nanoparticles W20/XD4-SPIONs were constructed by the conjugation of oligomer-specific scFv antibody W20 and class A scavenger receptor (SR-A) activator XD4 onto superparamagnetic iron oxide nanoparticles (SPIONs). The SPIONs' stability and uniformity in size were measured by dynamic light scattering and transmission electron microscopy. The ability of W20/XD4-SPIONs for recognizing Aß oligomers (AßOs) and promoting AßOs phagocytosis was assessed by immunocytochemistry and flow cytometry analysis. The blood-brain barrier permeability of W20/XD4-SPIONs was determined by a co-culture transwell model. The in vivo probe distribution of W20/XD4-SPIONs in AD mouse brains was detected by magnetic resonance imaging (MRI). RESULTS: W20/XD4-SPIONs, as an AßOs-targeted molecular MRI contrast probe, readily reached pathological AßOs regions in brains and distinguished AD transgenic mice from WT controls. W20/XD4-SPIONs retained the property of XD4 for SR-A activation and significantly promoted microglial phagocytosis of AßOs. Moreover, W20/XD4-SPIONs exhibited the properties of good biocompatibility, high stability and low cytotoxicity. CONCLUSION: Compared with W20-SPIONs or XD4-SPIONs, W20/XD4-SPIONs show the highest efficiency for AßOs-targeting and significantly enhance AßOs uptake by microglia. As a molecular probe, W20/XD4-SPIONs also specifically and sensitively bind to AßOs in AD brains to provide an MRI signal, demonstrating that W20/XD4-SPIONs are promising diagnostic agents for early-stage AD. Due to the beneficial effect of W20 and XD4 on neuropathology, W20/XD4-SPIONs may also have therapeutic potential for AD .


Subject(s)
Alzheimer Disease/diagnosis , Amyloid beta-Peptides/immunology , Immunoconjugates/chemistry , Magnetite Nanoparticles/chemistry , Receptors, Scavenger/metabolism , Single-Chain Antibodies/chemistry , Alzheimer Disease/metabolism , Alzheimer Disease/pathology , Animals , Antibody Specificity , Brain/drug effects , Brain/pathology , Early Diagnosis , Immunoconjugates/pharmacology , Magnetic Resonance Imaging , Mice , Mice, Transgenic , Microglia/drug effects , Microglia/pathology , Multifunctional Nanoparticles/chemistry , Phagocytosis/drug effects , Single-Chain Antibodies/immunology
14.
Int J Mol Sci ; 21(12)2020 Jun 24.
Article in English | MEDLINE | ID: mdl-32599696

ABSTRACT

It is widely accepted that ß-amyloid oligomers (Aßos) play a key role in the progression of Alzheimer's disease (AD) by inducing neuron damage and cognitive impairment, but Aßos are highly heterogeneous in their size, structure and cytotoxicity, making the corresponding studies tough to carry out. Nevertheless, a number of studies have recently made remarkable progress in the describing the characteristics and pathogenicity of Aßos. We here review the mechanisms by which Aßos exert their neuropathogenesis for AD progression, including receptor binding, cell membrane destruction, mitochondrial damage, Ca2+ homeostasis dysregulation and tau pathological induction. We also summarize the characteristics and pathogenicity such as the size, morphology and cytotoxicity of dimers, trimers, Aß*56 and spherical oligomers, and suggest that Aßos may play a different role at different phases of AD pathogenesis, resulting in differential consequences on neuronal synaptotoxicity and survival. It is warranted to investigate the temporal sequence of Aßos in AD human brain and examine the relationship between different Aßos and cognitive impairment.


Subject(s)
Alzheimer Disease/pathology , Amyloid beta-Peptides/chemistry , Amyloid beta-Peptides/metabolism , Protein Aggregation, Pathological , Alzheimer Disease/metabolism , Animals , Humans
15.
Vaccines (Basel) ; 8(3)2020 Jul 01.
Article in English | MEDLINE | ID: mdl-32630299

ABSTRACT

Immunotherapy focusing on reducing the amyloid-beta (Aß) burden is a promising treatment strategy for Alzheimer's disease (AD). Many clinical studies on AD immunotherapies have failed due to low safety and efficacy, calling for a highly potent AD vaccine which induces sufficient antibody titer while avoiding side effects. Here, we designed a yeast-based vaccine Y-5A15 comprising five copies of Aß1-15 displayed on the surface of yeast cell wall, and we subcutaneously immunized APP/PS1 mice three times. Our results demonstrated that the Y-5A15 remarkably enhanced the Aß epitope immunogenicity and elicited high antibody titers against Aß in AD mice. Importantly, Y-5A15 vaccination successfully reduced Aß levels, plaque burden and glial activation, rescued synaptic deficits and significantly ameliorated memory and cognitive decline in APP/PS1 transgenic mice, suggesting that the yeast-based Aß epitope vaccine has a promising potency for the treatment of AD.

16.
Nanomedicine ; 28: 102223, 2020 08.
Article in English | MEDLINE | ID: mdl-32422220

ABSTRACT

Personalized cancer vaccine which targets neoepitopes shows great promise for cancer treatment. However, rapid preparation is a critical challenge for clinical application of personalized cancer vaccine. Genetic recombination and chemical modification are a time-consuming "trial and error" pattern for making vaccines. Here we first constructed a platform for peptide vaccine preparation by inserting SpyCatcher into the major immunodominant region (MIR) of hepatitis B core protein (HBc) (1-183). The resulted recombinant protein HBc(1-183)-SpyCatcher (HBc(1-183)-S) assembled to virus-like particles (VLPs) and readily bound to SpyTag conjugated with OVA epitope peptides by just mixing, forming HBc(1-183)-S-OVA. HBc(1-183)-S-OVA VLPs effectively induced dendritic cell maturation. Our further results indicated that HBc(1-183)-S-OVA VLPs vaccination inhibited tumor growth in both prophylactic and treatment ways in E.G7-OVA tumor bearing mice by generating significant OVA-specific cytotoxic T lymphocyte responses. Our study provides a simple, rapid, efficient and universal HBc-based platform for the preparation of personalized cancer vaccine.


Subject(s)
Cancer Vaccines/immunology , Cancer Vaccines/therapeutic use , Hepatitis B Core Antigens/immunology , Animals , Cell Line , Dynamic Light Scattering , Female , Flow Cytometry , Mice , Mice, Inbred C57BL , Microscopy, Electron, Transmission , Precision Medicine/methods , Vaccines, Virus-Like Particle/chemistry , Vaccines, Virus-Like Particle/immunology
17.
Br J Pharmacol ; 177(12): 2860-2871, 2020 06.
Article in English | MEDLINE | ID: mdl-32034757

ABSTRACT

BACKGROUND AND PURPOSE: Immunotherapeutic intervention is one of the most promising strategies for the prevention and treatment of Alzheimer's disease (AD). Although they showed great success in AD mouse models, the clinical trials of many immune approaches failed due to low efficacy and safety. Thus, an animal model which can show the potential side effects of vaccines or antibodies is urgently needed. In this study, we generated EAE/AD mice by crossing APP/PS1 mice with experimental autoimmune encephalomyelitis (EAE) mice. We then investigated the efficacy and safety of two vaccines: the immunogens of which were Aß1-42 aggregates (Aß42 vaccine) and an oligomer-specific conformational epitope (AOE1 vaccine), respectively. EXPERIMENTAL APPROACH: EAE/AD mice were immunized with the Aß42 vaccine or AOE1 vaccine five times at biweekly intervals. After the final immunization, cognitive function was evaluated by the Morris water maze, Y maze, and object recognition tests. Neuropathological changes in the mouse brains were analysed by immunohistochemistry and ELISA. KEY RESULTS: In contrast to previous findings in conventional AD animal models, Aß42 immunization promoted neuroinflammation, enhanced Aß levels and plaque burden, and failed to restore cognitive deficits in EAE/AD mice. By contrast, AOE1 immunization dramatically attenuated neuroinflammation, reduced Aß levels, and improved cognitive performance in EAE/AD mice. CONCLUSION AND IMPLICATIONS: These results suggest that the EAE/AD mouse model can exhibit the potential side effects of AD immune approaches that conventional AD animal models fail to display. Furthermore, strategies specifically targeting Aß oligomers may be safe and show clinical benefit for AD treatment.


Subject(s)
Alzheimer Disease , Encephalomyelitis, Autoimmune, Experimental , Vaccines , Amino Acid Sequence , Amyloid beta-Peptides , Amyloid beta-Protein Precursor , Animals , Cognition , Disease Models, Animal , Epitopes , Mice , Mice, Inbred C57BL , Mice, Transgenic , Peptide Fragments
18.
Food Funct ; 11(2): 1334-1348, 2020 Feb 26.
Article in English | MEDLINE | ID: mdl-32043503

ABSTRACT

Huntington's disease (HD) is a genetic neurodegenerative disorder caused by a highly polymorphic CAG trinucleotide repeat expansion encoding an extended polyglutamine (polyQ) tract at the N-terminus of huntingtin protein (HTT). The polyQ tract promotes the formation of toxic oligomers and aggregates of HTT, which leads to neuronal dysfunction and death. Therapies to lower mutant HTT (mHTT) and its aggregates appear to be the most promising strategies. Ellagic acid (EA) has been marketed as a dietary supplement with various claimed benefits and neuroprotective effects on several neurodegenerative disorders, while its effect on mHTT pathology is still unknown. Here we reported that EA significantly attenuated motor and cognitive deficits in R6/2 mice. Moreover, EA significantly lowered mHTT levels, reduced neuroinflammation, rescued synapse loss, and decreased oxidative stress in R6/2 mouse brains. These findings indicated that EA has promising therapeutic potential for HD treatment.


Subject(s)
Cognitive Dysfunction/drug therapy , Ellagic Acid/pharmacology , Huntingtin Protein/drug effects , Huntington Disease/drug therapy , Neuroprotective Agents/pharmacology , Animals , Cognitive Dysfunction/metabolism , Disease Models, Animal , Female , Huntingtin Protein/genetics , Huntington Disease/metabolism , Mice , Mice, Transgenic , Motor Activity/drug effects
19.
Nanoscale Adv ; 2(8): 3494-3506, 2020 Aug 11.
Article in English | MEDLINE | ID: mdl-36134256

ABSTRACT

Enhancing both the humoral and cellular immune response for tumor vaccination remains a challenge. Inspired by natural pathogen structures, we took ß-glucan particles derived from a baker's yeast cell shell (YS) as a vaccine carrier and danger signal for dendritic cells (DCs), and coated the YS with catanionic layered double hydroxides (LDH) by electrostatic adsorption to form a biomimetic yeast cell particle (YSL). Our experimental results showed that the YSL vaccine efficiently targeted antigen-presenting cells (APCs) and remarkably enhanced antigen cross-presentation, and strongly improved the activation and maturation of DCs. Moreover, the YSL vaccine elicited an extremely high antibody titer and strong antigen-specific cytotoxic T lymphocyte together with mixed Th1/Th17 cellular immune responses and induced marked prophylactic and therapeutic effects against E.G7-OVA tumors in mouse models. These results suggest that YSL, integrating a yeast shell to mimic natural pathogens and LDH with high antigen-loading capacity and lysosome escape, is a promising tumor vaccine platform for rapid, effective and strong induction of both humoral and cellular immune responses.

20.
ACS Appl Mater Interfaces ; 11(39): 35566-35576, 2019 Oct 02.
Article in English | MEDLINE | ID: mdl-31496214

ABSTRACT

Cancer recurrence and metastasis are worldwide challenges but current bimodular strategies such as combined radiotherapy and chemotherapy (CTX), and photothermal therapy (PTT) and immunotherapy have succeeded only in some limited cases. Thus in the present study, a multifunctional nanomedicine has been rationally designed via elegantly integrating three FDA-approved therapeutics, that is, indocyanine green (for PTT), doxorubicin (for CTX), and CpG (for immunotherapy) into the structure of layered double hydroxide (LDH) nanoparticles, aiming to completely prevent the recurrence and metastasis of invasive breast cancer. This multifunctional hybrid nanomedicine has been demonstrated to eliminate the primary tumor and efficiently prevent tumor recurrence and lung metastasis through combined PTT/CTX and induction of specific and strong immune responses mediated by the hybrid nanomedicine in a 4T1 breast cancer mouse model. Furthermore, the promoted in situ immunity has significantly inhibited the growth of reinoculated distant tumors. Altogether, our multifunctional LDH-based nanomedicine has showed an excellent efficacy in invasive cancer treatment using much lower doses of three FDA-approved therapeutics, providing a preclinical/clinical alternative to cost-effectively treat invasive breast cancer.


Subject(s)
Breast Neoplasms , Clay/chemistry , Lung Neoplasms , Nanomedicine , Nanoparticles , Animals , Breast Neoplasms/metabolism , Breast Neoplasms/pathology , Breast Neoplasms/prevention & control , Female , Humans , Lung Neoplasms/metabolism , Lung Neoplasms/pathology , Lung Neoplasms/prevention & control , Lung Neoplasms/secondary , MCF-7 Cells , Mice , Mice, Inbred BALB C , Nanoparticles/chemistry , Nanoparticles/therapeutic use , Neoplasm Invasiveness , Neoplasm Metastasis , Xenograft Model Antitumor Assays
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