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Lu J, Wang Z, He Z, Hu Y, Duan H, Liu Z, Li D, Zhong S, Ren J, Zhao G, Mou Y, Yao M. Oligomer-Aβ42 suppress glioma progression via potentiating phagocytosis of microglia. CNS Neurosci Ther 2024; 30:e14495. [PMID: 37849438 PMCID: PMC10805446 DOI: 10.1111/cns.14495] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2023] [Revised: 09/12/2023] [Accepted: 10/01/2023] [Indexed: 10/19/2023] Open
Abstract
AIMS Glioma is characterized by an immunosuppressed environment and a poor prognosis. The accumulation of Amyloid β (Aβ) leads to an active environment during the early stages of Alzheimer's disease (AD). Aβ is also present in glioma tissues; however, the biological and translational implications of Aβ in glioma are elusive. METHODS Immunohistochemical (IHC) staining, Kaplan-Meier (KM) survival analysis and Cox regression analysis on a cohort of 79 patients from our institution were performed to investigate the association between Aβ and the malignancy of glioma. Subsequently, the potential of oligomer-Aβ42 (OAβ42) to inhibit glioma growth was investigated in vivo and in vitro. Immunofluorescence staining and phagocytosis assays were performed to evaluate the activation of microglia. Finally, RNA-seq was utilized to identify the predominant signaling involved in this process and in vitro studies were performed to validate them. RESULTS A positive correlation between Aβ and a favorable prognosis was observed in glioma. Furthermore, OAβ42 suppressed glioma growth by enhancing the phagocytic activity of microglia. Insulin-like growth factor 1 (IGF-1) secreted by OAβ42-activated microglia was essential in the engulfment process. CONCLUSION Our study proved an anti-glioma effect of Aβ, and microglia could serve as a cellular target for treating glioma with OAβ42.
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Affiliation(s)
- Jie Lu
- Department of Neurosurgery/Neuro‐oncologySun Yat‐sen University Cancer CenterGuangzhouChina
- State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer MedicineSun Yat‐sen University Cancer CenterGuangzhouChina
- The First Affiliated Hospital of Guangzhou Medical UniversityGuangzhou Institute of Respiratory Disease & China State Key Laboratory of Respiratory DiseaseGuangzhouChina
| | - Zhenning Wang
- Department of Neurosurgery, Dongguan People's Hospital (Affiliated Dongguan Hospital)Southern Medical UniversityDongguanChina
| | - Zhenqiang He
- Department of Neurosurgery/Neuro‐oncologySun Yat‐sen University Cancer CenterGuangzhouChina
- State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer MedicineSun Yat‐sen University Cancer CenterGuangzhouChina
| | - Yang Hu
- The First Affiliated Hospital of Guangzhou Medical UniversityGuangzhou Institute of Respiratory Disease & China State Key Laboratory of Respiratory DiseaseGuangzhouChina
| | - Hao Duan
- Department of Neurosurgery/Neuro‐oncologySun Yat‐sen University Cancer CenterGuangzhouChina
- State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer MedicineSun Yat‐sen University Cancer CenterGuangzhouChina
| | - Zihao Liu
- The First Affiliated Hospital of Guangzhou Medical UniversityGuangzhou Institute of Respiratory Disease & China State Key Laboratory of Respiratory DiseaseGuangzhouChina
| | - Depei Li
- Department of Neurosurgery/Neuro‐oncologySun Yat‐sen University Cancer CenterGuangzhouChina
- State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer MedicineSun Yat‐sen University Cancer CenterGuangzhouChina
| | - Sheng Zhong
- Department of Neurosurgery/Neuro‐oncologySun Yat‐sen University Cancer CenterGuangzhouChina
- State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer MedicineSun Yat‐sen University Cancer CenterGuangzhouChina
| | - Jiaoyan Ren
- School of Food Science and EngineeringSouth China University of TechnologyGuangzhouChina
| | - Guojun Zhao
- Laboratory Animal CenterThe Sixth Affiliated Hospital of Guangzhou Medical UniversityQingyuanChina
| | - Yonggao Mou
- Department of Neurosurgery/Neuro‐oncologySun Yat‐sen University Cancer CenterGuangzhouChina
- State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer MedicineSun Yat‐sen University Cancer CenterGuangzhouChina
| | - Maojin Yao
- The First Affiliated Hospital of Guangzhou Medical UniversityGuangzhou Institute of Respiratory Disease & China State Key Laboratory of Respiratory DiseaseGuangzhouChina
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2
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Novoa C, Salazar P, Cisternas P, Gherardelli C, Vera-Salazar R, Zolezzi JM, Inestrosa NC. Inflammation context in Alzheimer's disease, a relationship intricate to define. Biol Res 2022; 55:39. [PMID: 36550479 PMCID: PMC9784299 DOI: 10.1186/s40659-022-00404-3] [Citation(s) in RCA: 29] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2022] [Accepted: 11/15/2022] [Indexed: 12/24/2022] Open
Abstract
Alzheimer's disease (AD), the most common form of dementia, is characterized by the accumulation of amyloid β (Aβ) and hyperphosphorylated tau protein aggregates. Importantly, Aβ and tau species are able to activate astrocytes and microglia, which release several proinflammatory cytokines, such as tumor necrosis factor α (TNF-α) and interleukin 1β (IL-1β), together with reactive oxygen (ROS) and nitrogen species (RNS), triggering neuroinflammation. However, this inflammatory response has a dual function: it can play a protective role by increasing Aβ degradation and clearance, but it can also contribute to Aβ and tau overproduction and induce neurodegeneration and synaptic loss. Due to the significant role of inflammation in the pathogenesis of AD, several inflammatory mediators have been proposed as AD markers, such as TNF-α, IL-1β, Iba-1, GFAP, NF-κB, TLR2, and MHCII. Importantly, the use of anti-inflammatory drugs such as NSAIDs has emerged as a potential treatment against AD. Moreover, diseases related to systemic or local inflammation, including infections, cerebrovascular accidents, and obesity, have been proposed as risk factors for the development of AD. In the following review, we focus on key inflammatory processes associated with AD pathogenesis.
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Affiliation(s)
- Catalina Novoa
- grid.7870.80000 0001 2157 0406Centro de Envejecimiento y Regeneración (CARE-UC), Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Alameda Bernardo O’Higgins 340, P.O. Box 114-D, Santiago, Chile
| | - Paulina Salazar
- grid.7870.80000 0001 2157 0406Centro de Envejecimiento y Regeneración (CARE-UC), Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Alameda Bernardo O’Higgins 340, P.O. Box 114-D, Santiago, Chile
| | - Pedro Cisternas
- grid.499370.00000 0004 6481 8274Instituto de Ciencias de la Salud, Universidad de O’Higgins, Rancagua, Chile
| | - Camila Gherardelli
- grid.7870.80000 0001 2157 0406Centro de Envejecimiento y Regeneración (CARE-UC), Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Alameda Bernardo O’Higgins 340, P.O. Box 114-D, Santiago, Chile
| | - Roberto Vera-Salazar
- grid.412179.80000 0001 2191 5013Facultad de Ciencias Médicas, Escuela de Kinesiología, Universidad de Santiago de Chile, Santiago, Chile
| | - Juan M. Zolezzi
- grid.442242.60000 0001 2287 1761Centro de Excelencia en Biomedicina de Magallanes (CEBIMA), Escuela de Medicina, Universidad de Magallanes, Punta Arenas, Chile
| | - Nibaldo C. Inestrosa
- grid.7870.80000 0001 2157 0406Centro de Envejecimiento y Regeneración (CARE-UC), Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Alameda Bernardo O’Higgins 340, P.O. Box 114-D, Santiago, Chile ,grid.442242.60000 0001 2287 1761Centro de Excelencia en Biomedicina de Magallanes (CEBIMA), Escuela de Medicina, Universidad de Magallanes, Punta Arenas, Chile
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3
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Bello-Medina PC, Corona-Cervantes K, Zavala Torres NG, González A, Pérez-Morales M, González-Franco DA, Gómez A, García-Mena J, Díaz-Cintra S, Pacheco-López G. Chronic-Antibiotics Induced Gut Microbiota Dysbiosis Rescues Memory Impairment and Reduces β-Amyloid Aggregation in a Preclinical Alzheimer's Disease Model. Int J Mol Sci 2022; 23:8209. [PMID: 35897785 PMCID: PMC9331718 DOI: 10.3390/ijms23158209] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2022] [Revised: 07/08/2022] [Accepted: 07/12/2022] [Indexed: 02/03/2023] Open
Abstract
Alzheimer's disease (AD) is a multifactorial pathology characterized by β-amyloid (Aβ) deposits, Tau hyperphosphorylation, neuroinflammatory response, and cognitive deficit. Changes in the bacterial gut microbiota (BGM) have been reported as a possible etiological factor of AD. We assessed in offspring (F1) 3xTg, the effect of BGM dysbiosisdysbiosis in mothers (F0) at gestation and F1 from lactation up to the age of 5 months on Aβ and Tau levels in the hippocampus, as well as on spatial memory at the early symptomatic stage of AD. We found that BGM dysbiosisdysbiosis with antibiotics (Abx) treatment in F0 was vertically transferred to their F1 3xTg mice, as observed on postnatal day (PD) 30 and 150. On PD150, we observed a delay in spatial memory impairment and Aβ deposits, but not in Tau and pTau protein in the hippocampus at the early symptomatic stage of AD. These effects are correlated with relative abundance of bacteria and alpha diversity, and are specific to bacterial consortia. Our results suggest that this specific BGM could reduce neuroinflammatory responses related to cerebral amyloidosis and cognitive deficit and activate metabolic pathways associated with the biosynthesis of triggering or protective molecules for AD.
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Affiliation(s)
- Paola C. Bello-Medina
- Departamento de Neurobiología del Desarrollo y Neurofisiología, Instituto de Neurobiología, Universidad Nacional Autónoma de México, Querétaro 76230, Mexico;
- Biological and Health Sciences Division, Campus Lerma, Metropolitan Autonomus University (UAM), Lerma 52005, Mexico; (A.G.); (M.P.-M.); (D.A.G.-F.); (A.G.); (G.P.-L.)
| | - Karina Corona-Cervantes
- Departamento de Genética y Biología Molecular, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Unidad Zacatenco, Mexico City 07360, Mexico; (K.C.-C.); (N.G.Z.T.)
| | - Norma Gabriela Zavala Torres
- Departamento de Genética y Biología Molecular, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Unidad Zacatenco, Mexico City 07360, Mexico; (K.C.-C.); (N.G.Z.T.)
| | - Antonio González
- Biological and Health Sciences Division, Campus Lerma, Metropolitan Autonomus University (UAM), Lerma 52005, Mexico; (A.G.); (M.P.-M.); (D.A.G.-F.); (A.G.); (G.P.-L.)
| | - Marcel Pérez-Morales
- Biological and Health Sciences Division, Campus Lerma, Metropolitan Autonomus University (UAM), Lerma 52005, Mexico; (A.G.); (M.P.-M.); (D.A.G.-F.); (A.G.); (G.P.-L.)
| | - Diego A. González-Franco
- Biological and Health Sciences Division, Campus Lerma, Metropolitan Autonomus University (UAM), Lerma 52005, Mexico; (A.G.); (M.P.-M.); (D.A.G.-F.); (A.G.); (G.P.-L.)
| | - Astrid Gómez
- Biological and Health Sciences Division, Campus Lerma, Metropolitan Autonomus University (UAM), Lerma 52005, Mexico; (A.G.); (M.P.-M.); (D.A.G.-F.); (A.G.); (G.P.-L.)
| | - Jaime García-Mena
- Departamento de Genética y Biología Molecular, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Unidad Zacatenco, Mexico City 07360, Mexico; (K.C.-C.); (N.G.Z.T.)
| | - Sofía Díaz-Cintra
- Departamento de Neurobiología del Desarrollo y Neurofisiología, Instituto de Neurobiología, Universidad Nacional Autónoma de México, Querétaro 76230, Mexico;
| | - Gustavo Pacheco-López
- Biological and Health Sciences Division, Campus Lerma, Metropolitan Autonomus University (UAM), Lerma 52005, Mexico; (A.G.); (M.P.-M.); (D.A.G.-F.); (A.G.); (G.P.-L.)
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4
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Cutuli D, Giacovazzo G, Decandia D, Coccurello R. Alzheimer's disease and depression in the elderly: A trajectory linking gut microbiota and serotonin signaling. Front Psychiatry 2022; 13:1010169. [PMID: 36532180 PMCID: PMC9750201 DOI: 10.3389/fpsyt.2022.1010169] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/02/2022] [Accepted: 10/28/2022] [Indexed: 12/05/2022] Open
Abstract
The occurrence of neuropsychiatric symptoms in the elderly is viewed as an early sign of subsequent cognitive deterioration and conversion from mild cognitive impairment to Alzheimer's disease. The prognosis in terms of both the severity and progression of clinical dementia is generally aggravated by the comorbidity of neuropsychiatric symptoms and decline in cognitive function. Undeniably, aging and in particular unhealthy aging, is a silent "engine of neuropathology" over which multiple changes take place, including drastic alterations of the gut microbial ecosystem. This narrative review evaluates the role of gut microbiota changes as a possible unifying concept through which the comorbidity of neuropsychiatric symptoms and Alzheimer's disease can be considered. However, since the heterogeneity of neuropsychiatric symptoms, it is improbable to describe the same type of alterations in the bacteria population observed in patients with Alzheimer's disease, as well as it is improbable that the variety of drugs used to treat neuropsychiatric symptoms might produce changes in gut bacterial diversity similar to that observed in the pathophysiology of Alzheimer's disease. Depression seems to be another very intriguing exception, as it is one of the most frequent neuropsychiatric symptoms in dementia and a mood disorder frequently associated with brain aging. Antidepressants (i.e., serotonin reuptake inhibitors) or tryptophan dietary supplementation have been shown to reduce Amyloid β-loading, reinstate microbial diversity and reduce the abundance of bacterial taxa dominant in depression and Alzheimer's disease. This review briefly examines this trajectory by discussing the dysfunction of gut microbiota composition, selected bacterial taxa, and alteration of tryptophan and serotonin metabolism/neurotransmission as overlapping in-common mechanisms involved with depression, Alzheimer's disease, and unhealthy aging.
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Affiliation(s)
- Debora Cutuli
- Department of Psychology, University of Rome La Sapienza, Rome, Italy.,European Center for Brain Research, Santa Lucia Foundation IRCCS, Rome, Italy
| | - Giacomo Giacovazzo
- European Center for Brain Research, Santa Lucia Foundation IRCCS, Rome, Italy
| | - Davide Decandia
- Department of Psychology, University of Rome La Sapienza, Rome, Italy.,European Center for Brain Research, Santa Lucia Foundation IRCCS, Rome, Italy
| | - Roberto Coccurello
- European Center for Brain Research, Santa Lucia Foundation IRCCS, Rome, Italy.,Institute for Complex Systems (ISC), National Council of Research (CNR), Rome, Italy
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5
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Bello-Medina PC, Hernández-Quiroz F, Pérez-Morales M, González-Franco DA, Cruz-Pauseno G, García-Mena J, Díaz-Cintra S, Pacheco-López G. Spatial Memory and Gut Microbiota Alterations Are Already Present in Early Adulthood in a Pre-clinical Transgenic Model of Alzheimer's Disease. Front Neurosci 2021; 15:595583. [PMID: 33994914 PMCID: PMC8116633 DOI: 10.3389/fnins.2021.595583] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2020] [Accepted: 03/19/2021] [Indexed: 12/14/2022] Open
Abstract
The irreversible and progressive neurodegenerative Alzheimer’s disease (AD) is characterized by cognitive decline, extracellular β-amyloid peptide accumulation, and tau neurofibrillary tangles in the cortex and hippocampus. The triple-transgenic (3xTg) mouse model of AD presents memory impairment in several behavioral paradigms and histopathological alterations from 6 to 16 months old. Additionally, it seems that dysbiotic gut microbiota is present in both mouse models and patients of AD at the cognitive symptomatic stage. The present study aimed to assess spatial learning, memory retention, and gut microbiota alterations in an early adult stage of the 3xTg-AD mice as well as to explore its sexual dimorphism. We evaluated motor activity, novel-object localization training, and retention test as well as collected fecal samples to characterize relative abundance, alpha- and beta-diversity, and linear discriminant analysis (LDA) effect size (LEfSe) analysis in gut microbiota in both female and male 3xTg-AD mice, and controls [non-transgenic mice (NoTg)], at 3 and 5 months old. We found spatial memory deficits in female and male 3xTg-AD but no alteration neither during training nor in motor activity. Importantly, already at 3 months old, we observed decreased relative abundances of Actinobacteria and TM7 in 3xTg-AD compared to NoTg mice, while the beta diversity of gut microbiota was different in female and male 3xTg-AD mice in comparison to NoTg. Our results suggest that gut microbiota modifications in 3xTg-AD mice anticipate and thus could be causally related to cognitive decline already at the early adult age of AD. We propose that microbiota alterations may be used as an early and non-invasive diagnostic biomarker of AD.
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Affiliation(s)
- Paola C Bello-Medina
- División de Ciencias Biológicas y de la Salud, Universidad Autónoma Metropolitana (UAM), Unidad Lerma, Lerma, Mexico
| | - Fernando Hernández-Quiroz
- Departamento de Genética y Biología Molecular, Centro de Investigación y de Estudios Avanzados (CINVESTAV) del Instituto Politécnico Nacional (IPN), Unidad Zacatenco, Ciudad de México, Mexico
| | - Marcel Pérez-Morales
- División de Ciencias Biológicas y de la Salud, Universidad Autónoma Metropolitana (UAM), Unidad Lerma, Lerma, Mexico
| | - Diego A González-Franco
- División de Ciencias Biológicas y de la Salud, Universidad Autónoma Metropolitana (UAM), Unidad Lerma, Lerma, Mexico
| | - Guadalupe Cruz-Pauseno
- Doctorado en Ciencias Biológicas y de la Salud, Universidad Autónoma Metropolitana (UAM), Unidad Lerma, Lerma, Mexico
| | - Jaime García-Mena
- Departamento de Genética y Biología Molecular, Centro de Investigación y de Estudios Avanzados (CINVESTAV) del Instituto Politécnico Nacional (IPN), Unidad Zacatenco, Ciudad de México, Mexico
| | - Sofía Díaz-Cintra
- Departamento de Neurobiología del Desarrollo y Neurofisiología, Instituto de Neurobiología, Universidad Nacional Autónoma de México (UNAM), Querétaro, Mexico
| | - Gustavo Pacheco-López
- División de Ciencias Biológicas y de la Salud, Universidad Autónoma Metropolitana (UAM), Unidad Lerma, Lerma, Mexico
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6
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Pinheiro L, Faustino C. Therapeutic Strategies Targeting Amyloid-β in Alzheimer's Disease. Curr Alzheimer Res 2020; 16:418-452. [PMID: 30907320 DOI: 10.2174/1567205016666190321163438] [Citation(s) in RCA: 73] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2018] [Revised: 03/16/2019] [Accepted: 03/17/2019] [Indexed: 12/16/2022]
Abstract
Alzheimer's disease (AD) is a neurodegenerative disorder linked to protein misfolding and aggregation. AD is pathologically characterized by senile plaques formed by extracellular Amyloid-β (Aβ) peptide and Intracellular Neurofibrillary Tangles (NFT) formed by hyperphosphorylated tau protein. Extensive synaptic loss and neuronal degeneration are responsible for memory impairment, cognitive decline and behavioral dysfunctions typical of AD. Amyloidosis has been implicated in the depression of acetylcholine synthesis and release, overactivation of N-methyl-D-aspartate (NMDA) receptors and increased intracellular calcium levels that result in excitotoxic neuronal degeneration. Current drugs used in AD treatment are either cholinesterase inhibitors or NMDA receptor antagonists; however, they provide only symptomatic relief and do not alter the progression of the disease. Aβ is the product of Amyloid Precursor Protein (APP) processing after successive cleavage by β- and γ-secretases while APP proteolysis by α-secretase results in non-amyloidogenic products. According to the amyloid cascade hypothesis, Aβ dyshomeostasis results in the accumulation and aggregation of Aβ into soluble oligomers and insoluble fibrils. The former are synaptotoxic and can induce tau hyperphosphorylation while the latter deposit in senile plaques and elicit proinflammatory responses, contributing to oxidative stress, neuronal degeneration and neuroinflammation. Aβ-protein-targeted therapeutic strategies are thus a promising disease-modifying approach for the treatment and prevention of AD. This review summarizes recent findings on Aβ-protein targeted AD drugs, including β-secretase inhibitors, γ-secretase inhibitors and modulators, α-secretase activators, direct inhibitors of Aβ aggregation and immunotherapy targeting Aβ, focusing mainly on those currently under clinical trials.
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Affiliation(s)
- Lídia Pinheiro
- iMed.ULisboa - Research Institute for Medicines, Faculty of Pharmacy, Universidade de Lisboa, Av. Prof. Gama Pinto 1649-003 Lisboa, Portugal
| | - Célia Faustino
- iMed.ULisboa - Research Institute for Medicines, Faculty of Pharmacy, Universidade de Lisboa, Av. Prof. Gama Pinto 1649-003 Lisboa, Portugal
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7
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Microglia Do Not Take Up Soluble Amyloid-beta Peptides, But Partially Degrade Them by Secreting Insulin-degrading Enzyme. Neuroscience 2020; 443:30-43. [PMID: 32697980 DOI: 10.1016/j.neuroscience.2020.07.020] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2020] [Revised: 07/03/2020] [Accepted: 07/13/2020] [Indexed: 12/12/2022]
Abstract
Microglia play important roles in the pathogenesis of Alzheimer's disease (AD), in part, by affecting the clearance of amyloid-β (Aβ) peptides. Most studies, however, used synthetic soluble Aβ (sAβ) at higher concentrations. The exact mechanisms underlying microglia-mediated clearance of physiological sAβ at very low concentrations remain unclear. Here we reported that there were much more Iba-1- and CD68-positive microglia and significantly less sAβ left in the brain of adult mice 5 days after the surgery of sAβ microinjection compared to 2 h after the surgery (p < 0.05). However, very few Iba-1- and CD68-positive microglia co-localized with microinjected fluorescently labeled sAβ (FLsAβ42) 5 days after the surgery. Also, there was no co-localization of FLsAβ42 with a lysosomal marker (LAMP-1) 5 days after the surgery. There was no significant difference in the percentage of Aβ+/PE-CD11b+/APC-CD45low microglia between the control group and the group microinjected with TBS-soluble Aβ extracted from the brains of AD patients (p > 0.05). The degradation of physiological sAβ was prevented by a highly selective insulin-degrading enzyme inhibitor (Ii1) but not by a phagocytosis inhibitor (polyinosinic acid) or pinocytosis inhibitor (cytochalasin B) in vitro. Furthermore, the reduction of synthetic and physiological sAβ in the brain was partially prevented by the co-injection of Ii1 in vivo (p < 0.05). Our results demonstrate that microglia do not take up synthetic or physiological sAβ, but partially degrade it via the secretion of insulin-degrading enzyme, which will be beneficial for understanding how sAβ is removed from the brain by microglia.
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8
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Pakdeepak K, Chokchaisiri R, Tocharus J, Jearjaroen P, Tocharus C, Suksamrarn A. 5,6,7,4'-Tetramethoxyflavanone protects against neuronal degeneration induced by dexamethasone by attenuating amyloidogenesis in mice. EXCLI JOURNAL 2020; 19:16-32. [PMID: 32038114 PMCID: PMC7003641 DOI: 10.17179/excli2019-1940] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/31/2019] [Accepted: 12/04/2019] [Indexed: 12/31/2022]
Abstract
Long-term exposure to high glucocorticoid levels induces memory impairment and neurodegeneration in Alzheimer's disease (AD) by increasing the expression of amyloid β and tau hyperphosphorylation (pTau). Previous studies showed beneficial effects of flavonoids in neurodegenerative models. 5,6,7,4'-tetramethoxyflavanone (TMF) is one of the active ingredients in Chromolaena odorata (L.), which R. M. King and H. Rob discovered in Thailand. This study focused on the effects of TMF on dexamethasone (DEX)-induced neurodegeneration, amyloidogenesis, pTau expression, neuron synaptic function, and cognitive impairment and the potential mechanisms involved. Mice were intraperitoneally administered DEX for 28 days before being treated with TMF for 30 days. The mice were randomly divided into six groups (twelve mice per group): control; TMF administration (40 mg/kg); pioglitazone administration (20 mg/kg); DEX administration (60 mg/kg); DEX administration plus TMF; and DEX administration plus pioglitazone. Behavioral tests showed that TMF significantly attenuated the memory impairment triggered by DEX. Consistently, TMF reduced DEX-induced amyloid beta production by reducing the expression of beta-site APP cleaving enzyme 1 (BACE1) and presenilin 1 (PS1), whereas it increased the gene expression of a disintegrin and metalloprotease 10 (ADAM10). TMF treatment also decreased pTau expression, inhibited phosphonuclear factor-kappa B (pNF-kB) and inhibited glycogen synthase kinase 3 (GSK-3) activity by increasing GSK3 phosphorylation (pGSK3). In addition, TMF also improved synaptic function by increasing the expression of synaptophysin (Syn) and postsynaptic density protein 95 (PSD95) while decreasing acetylcholine esterase activity. Conclusively, TMF provided neuroprotection against DEX-induced neurodegeneration. These findings suggest that TMF might have potential as a therapeutic drug for AD.
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Affiliation(s)
- Kanet Pakdeepak
- Department of Physiology, Faculty of Medicine, Chiang Mai University, Chiang Mai 50200, Thailand.,Graduate School, Chiang Mai University, Chiang Mai 50200, Thailand
| | | | - Jiraporn Tocharus
- Department of Physiology, Faculty of Medicine, Chiang Mai University, Chiang Mai 50200, Thailand
| | | | - Chainarong Tocharus
- Department of Anatomy, Faculty of Medicine, Chiang Mai University, Chiang Mai 50200, Thailand
| | - Apichart Suksamrarn
- Department of Chemistry and Center of Excellence for Innovation in Chemistry, Faculty of Science, Ramkhamhaeng University, Bangkok 10240, Thailand
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Lučiūnaitė A, McManus RM, Jankunec M, Rácz I, Dansokho C, Dalgėdienė I, Schwartz S, Brosseron F, Heneka MT. Soluble Aβ oligomers and protofibrils induce NLRP3 inflammasome activation in microglia. J Neurochem 2020; 155:650-661. [DOI: 10.1111/jnc.14945] [Citation(s) in RCA: 57] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2019] [Revised: 12/13/2019] [Accepted: 12/13/2019] [Indexed: 12/17/2022]
Affiliation(s)
- Asta Lučiūnaitė
- Institute of Biotechnology, Life Sciences Center Vilnius University Vilnius Lithuania
- Department of Neurodegenerative Disease and Geriatric PsychiatryBonn Germany
- German Center for Neurodegenerative Disease (DZNE) Bonn Germany
| | - Róisín M. McManus
- Department of Neurodegenerative Disease and Geriatric PsychiatryBonn Germany
- German Center for Neurodegenerative Disease (DZNE) Bonn Germany
| | - Marija Jankunec
- Institute of Biochemistry, Life Sciences Center Vilnius University Vilnius Lithuania
| | - Ildikó Rácz
- Department of Neurodegenerative Disease and Geriatric PsychiatryBonn Germany
| | - Cira Dansokho
- Department of Neurodegenerative Disease and Geriatric PsychiatryBonn Germany
- German Center for Neurodegenerative Disease (DZNE) Bonn Germany
| | - Indrė Dalgėdienė
- Institute of Biotechnology, Life Sciences Center Vilnius University Vilnius Lithuania
| | - Stephanie Schwartz
- Department of Neurodegenerative Disease and Geriatric PsychiatryBonn Germany
| | | | - Michael T. Heneka
- Department of Neurodegenerative Disease and Geriatric PsychiatryBonn Germany
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Elia CA, Losurdo M, Malosio ML, Coco S. Extracellular Vesicles from Mesenchymal Stem Cells Exert Pleiotropic Effects on Amyloid-β, Inflammation, and Regeneration: A Spark of Hope for Alzheimer's Disease from Tiny Structures? Bioessays 2019; 41:e1800199. [PMID: 30919493 DOI: 10.1002/bies.201800199] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2018] [Revised: 02/08/2019] [Indexed: 12/15/2022]
Abstract
No cure yet exists for devastating Alzheimer's disease (AD), despite many years and humongous efforts to find efficacious pharmacological treatments. So far, neither designing drugs to disaggregate amyloid plaques nor tackling solely inflammation turned out to be decisive. Mesenchymal stem cells (MSCs) and, in particular, extracellular vesicles (EVs) originating from them could be proposed as an alternative, strategic approach to attack the pathology. Indeed, MSC-EVs-owing to their ability to deliver lipids/proteins/enzymes/microRNAs endowed with anti-inflammatory, amyloid-β degrading, and neurotrophic activities-may be exploited as therapeutic tools to restore synaptic function, prevent neuronal death, and slow down memory impairment in AD. Herein the results presented in the most recently published studies on this topic are critically evaluated, providing a strong rationale for possible employment of MSC-EVs in AD. Also see the video abstract here https://youtu.be/tBtDbnlRUhg.
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Affiliation(s)
- Chiara A Elia
- Laboratory of Pharmacology and Brain Pathology, Neuro Center, Humanitas Clinical and Research Center-IRCCS, Via Manzoni 56, Rozzano, Milano, 20089, Italy
| | - Morris Losurdo
- School of Medicine and Surgery, NeuroMI-Milan Center for Neuroscience, University of Milano-Bicocca, Via Cadore 48, Monza, 20900, Italy
| | - Maria L Malosio
- Laboratory of Pharmacology and Brain Pathology, Neuro Center, Humanitas Clinical and Research Center-IRCCS, Via Manzoni 56, Rozzano, Milano, 20089, Italy.,CNR, Institute of Neuroscience, Via Vanvitelli 32, Milano, 20129, Italy
| | - Silvia Coco
- School of Medicine and Surgery, NeuroMI-Milan Center for Neuroscience, University of Milano-Bicocca, Via Cadore 48, Monza, 20900, Italy
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11
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p110δ PI3-Kinase Inhibition Perturbs APP and TNFα Trafficking, Reduces Plaque Burden, Dampens Neuroinflammation, and Prevents Cognitive Decline in an Alzheimer's Disease Mouse Model. J Neurosci 2019; 39:7976-7991. [PMID: 31363064 DOI: 10.1523/jneurosci.0674-19.2019] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2019] [Revised: 06/26/2019] [Accepted: 07/22/2019] [Indexed: 12/18/2022] Open
Abstract
Alzheimer's disease (AD) is associated with the cleavage of the amyloid precursor protein (APP) to produce the toxic amyloid-β (Aβ) peptide. Accumulation of Aβ, together with the concomitant inflammatory response, ultimately leads to neuronal death and cognitive decline. Despite AD progression being underpinned by both neuronal and immunological components, therapeutic strategies based on dual targeting of these systems remains unexplored. Here, we report that inactivation of the p110δ isoform of phosphoinositide 3-kinase (PI3K) reduces anterograde axonal trafficking of APP in hippocampal neurons and dampens secretion of the inflammatory cytokine tumor necrosis factor-alpha by microglial cells in the familial AD APPswe/PS1ΔE9 (APP/PS1) mouse model. Moreover, APP/PS1 mice with kinase-inactive PI3Kδ (δD910A) had reduced Aβ peptides levels and plaques in the brain and an abrogated inflammatory response compared with APP/PS1 littermates. Mechanistic investigations reveal that PI3Kδ inhibition decreases the axonal transport of APP by eliciting the formation of highly elongated tubular-shaped APP-containing carriers, reducing the levels of secreted Aβ peptide. Importantly, APP/PS1/δD910A mice exhibited no spatial learning or memory deficits. Our data highlight inhibition of PI3Kδ as a new approach to protect against AD pathology due to its dual action of dampening microglial-dependent neuroinflammation and reducing plaque burden by inhibition of neuronal APP trafficking and processing.SIGNIFICANCE STATEMENT During Alzheimer's disease (AD), the accumulation of the toxic amyloid-β (Aβ) peptide in plaques is associated with a chronic excessive inflammatory response. Uncovering new drug targets that simultaneously reduce both Aβ plaque load and neuroinflammation holds therapeutic promise. Using a combination of genetic and pharmacological approaches, we found that the p110δ isoform of phosphoinositide 3-kinase (PI3K) is involved in anterograde trafficking of the amyloid precursor protein in neurons and in the secretion of tumor necrosis factor-alpha from microglial cells. Genetic inactivation of PI3Kδ reduces Aβ plaque deposition and abrogates the inflammatory response, resulting in a complete rescue of the life span and spatial memory performance. We conclude that inhibiting PI3Kδ represents a novel therapeutic approach to ameliorate AD pathology by dampening plaque accumulation and microglial-dependent neuroinflammation.
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12
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Petrov AM, Lam M, Mast N, Moon J, Li Y, Maxfield E, Pikuleva IA. CYP46A1 Activation by Efavirenz Leads to Behavioral Improvement without Significant Changes in Amyloid Plaque Load in the Brain of 5XFAD Mice. Neurotherapeutics 2019; 16:710-724. [PMID: 31062296 PMCID: PMC6694340 DOI: 10.1007/s13311-019-00737-0] [Citation(s) in RCA: 55] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Efavirenz, the FDA-approved anti-retroviral medication, is evaluated in the clinical trial in patients with mild cognitive impairment or early dementia due to Alzheimer's disease. Efavirenz is assessed for activation of cytochrome P450 46A1 (CYP46A1), a CNS-specific enzyme that converts cholesterol to 24-hydroxycholesterol. Cholesterol 24-hydroxylation is the major pathway for brain cholesterol removal, and a mechanism that controls brain cholesterol turnover. The present study tested efavirenz on 5XFAD mice (an Alzheimer's model) at a very low daily dose of 0.1 mg/kg body weight. Efavirenz treatment started from three months of age, after amyloid plague appearance, and continued for 6 months. This treatment led to CYP46A1 activation in the brain, enhancement of brain cholesterol turnover, behavioral improvements, reduction in microglia activation but increased astrocyte reactivity. The levels of the soluble and insoluble amyloid 40 and 42 peptides were unchanged while the number and area of the dense core amyloid plaques were slightly decreased. The measurements of the brain levels of several pre- and post-synaptic proteins (Munc13-1, PSD-95, gephyrin, synaptophysin, synapsin-1, and calbindin-D28k) suggested efavirenz effect at the synaptic level. Efavirenz treatment in the present work seems to represent a model of behavioral and other improvements independent of the levels of the amyloid peptides and provides insight into potential outcomes of the future clinical trial.
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Affiliation(s)
- Alexey M Petrov
- Department of Ophthalmology and Visual Sciences, Case Western Reserve University, 2085 Adelbert Rd., Room 303, Cleveland, OH, 44106, USA
| | - Morrie Lam
- Department of Ophthalmology and Visual Sciences, Case Western Reserve University, 2085 Adelbert Rd., Room 303, Cleveland, OH, 44106, USA
| | - Natalia Mast
- Department of Ophthalmology and Visual Sciences, Case Western Reserve University, 2085 Adelbert Rd., Room 303, Cleveland, OH, 44106, USA
| | - Jean Moon
- Department of Ophthalmology and Visual Sciences, Case Western Reserve University, 2085 Adelbert Rd., Room 303, Cleveland, OH, 44106, USA
| | - Yong Li
- Department of Ophthalmology and Visual Sciences, Case Western Reserve University, 2085 Adelbert Rd., Room 303, Cleveland, OH, 44106, USA
| | - Erin Maxfield
- Department of Ophthalmology and Visual Sciences, Case Western Reserve University, 2085 Adelbert Rd., Room 303, Cleveland, OH, 44106, USA
| | - Irina A Pikuleva
- Department of Ophthalmology and Visual Sciences, Case Western Reserve University, 2085 Adelbert Rd., Room 303, Cleveland, OH, 44106, USA.
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13
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Activation of Macrophages by Oligomeric Proteins of Different Size and Origin. Mediators Inflamm 2018; 2018:7501985. [PMID: 30581370 PMCID: PMC6276464 DOI: 10.1155/2018/7501985] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2018] [Accepted: 09/25/2018] [Indexed: 02/06/2023] Open
Abstract
Activation of macrophages is one of the key processes in generating the immune response against pathogens or misfolded/aggregated otherwise unharmful host's proteins. Antigens and their immune complexes (IC) may shape macrophage phenotype in various directions. Data on the impact of protein structure during inflammation are evident; however, some separate steps of this process involving changes in macrophage phenotype are not fully understood. Our aim was to investigate the phenotype of macrophages after activation with different oligomeric proteins and their IC. We have used amyloid beta (Aβ 1-42) that plays a role in neurodegenerative inflammation as a model of host-associated protein and three oligomeric viral antigens as pathogen-associated proteins. Murine cell lines J774, BV-2, and macrophage primary cell culture were treated with oligomeric proteins and their IC. After 48 h, expression of surface markers F4/80, CD68, CD86, and CD206 and secreted cytokines IL-10, IL-12, IL-23, and TNF-α was analysed. Aβ 1-42 oligomers stimulated expression of both inflammatory and anti-inflammatory molecules; however, fibrils induced less intense expression of markers investigated as compared to small and large oligomers. Two out of three viral oligomeric proteins induced the inflammatory response of macrophages. Data suggest that macrophage activation pattern depends on the origin, size, and structure of oligomeric proteins.
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14
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Uncaria rhynchophylla ameliorates amyloid beta deposition and amyloid beta-mediated pathology in 5XFAD mice. Neurochem Int 2018; 121:114-124. [PMID: 30291956 DOI: 10.1016/j.neuint.2018.10.003] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2018] [Revised: 09/21/2018] [Accepted: 10/01/2018] [Indexed: 01/31/2023]
Abstract
One of the pathological hallmarks of Alzheimer's disease (AD) is the abnormal aggregation of amyloid beta (Aβ) peptides. Uncaria rhynchophylla (UR), one of the Uncaria species, has long been used to treat neurodegenerative disease. In particular, it has been reported that UR inhibits aggregation of Aβ in vitro. However, little is known about the histological effects of UR treatment on Aβ pathology in AD animal models. In the present study, we investigated the effect of UR on Aβ aggregation, Aβ-mediated pathologies and adult hippocampal neurogenesis in the brain of 5XFAD mice. First, using the thioflavin T assay and amyloid staining, we demonstrated that UR treatment effectively inhibited Aβ aggregation and accumulation in the cortex and subiculum. Second, immunofluorescence staining showed that administration of UR attenuated gliosis and neurodegeneration in the subiculum and cortex. Third, UR treatment ameliorated impaired adult hippocampal neurogenesis. The present results indicate that UR significantly alleviates Aβ deposition and Aβ-mediated neuropathology in the brain in 5XFAD mice, suggesting the potency of UR as a preventive and therapeutic agent for AD.
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15
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Zhao Y, Jaber V, Lukiw WJ. Secretory Products of the Human GI Tract Microbiome and Their Potential Impact on Alzheimer's Disease (AD): Detection of Lipopolysaccharide (LPS) in AD Hippocampus. Front Cell Infect Microbiol 2017; 7:318. [PMID: 28744452 PMCID: PMC5504724 DOI: 10.3389/fcimb.2017.00318] [Citation(s) in RCA: 250] [Impact Index Per Article: 35.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2017] [Accepted: 06/27/2017] [Indexed: 12/12/2022] Open
Abstract
Although the potential contribution of the human gastrointestinal (GI) tract microbiome to human health, aging, and disease is becoming increasingly acknowledged, the molecular mechanics and signaling pathways of just how this is accomplished is not well-understood. Major bacterial species of the GI tract, such as the abundant Gram-negative bacilli Bacteroides fragilis (B. fragilis) and Escherichia coli (E. coli), secrete a remarkably complex array of pro-inflammatory neurotoxins which, when released from the confines of the healthy GI tract, are pathogenic and highly detrimental to the homeostatic function of neurons in the central nervous system (CNS). For the first time here we report the presence of bacterial lipopolysaccharide (LPS) in brain lysates from the hippocampus and superior temporal lobe neocortex of Alzheimer's disease (AD) brains. Mean LPS levels varied from two-fold increases in the neocortex to three-fold increases in the hippocampus, AD over age-matched controls, however some samples from advanced AD hippocampal cases exhibited up to a 26-fold increase in LPS over age-matched controls. This “Perspectives” paper will further highlight some very recent research on GI tract microbiome signaling to the human CNS, and will update current findings that implicate GI tract microbiome-derived LPS as an important internal contributor to inflammatory degeneration in the CNS.
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Affiliation(s)
- Yuhai Zhao
- LSU Neuroscience Center, Louisiana State University Health Science CenterNew Orleans, LA, United States.,Department of Anatomy and Cell Biology, Louisiana State University Health Science CenterNew Orleans, LA, United States
| | - Vivian Jaber
- LSU Neuroscience Center, Louisiana State University Health Science CenterNew Orleans, LA, United States
| | - Walter J Lukiw
- LSU Neuroscience Center, Louisiana State University Health Science CenterNew Orleans, LA, United States.,Department of Ophthalmology, Louisiana State University Health Science CenterNew Orleans, LA, United States.,Department of Neurology, Louisiana State University Health Science CenterNew Orleans, LA, United States
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16
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Mahajani S, Giacomini C, Marinaro F, De Pietri Tonelli D, Contestabile A, Gasparini L. Lamin B1 levels modulate differentiation into neurons during embryonic corticogenesis. Sci Rep 2017; 7:4897. [PMID: 28687747 PMCID: PMC5501862 DOI: 10.1038/s41598-017-05078-6] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2016] [Accepted: 05/24/2017] [Indexed: 01/10/2023] Open
Abstract
Lamin B1, a key component of the nuclear lamina, plays an important role in brain development. Ablation of endogenous Lamin B1 (Lmnb1) in the mouse strongly impairs embryonic brain development and corticogenesis. However, the mechanisms underlying these neurodevelopmental effects are unknown. Here, we report that Lamin B1 levels modulate the differentiation of murine neural stem cells (NSCs) into neurons and astroglial-like cells. In vitro, endogenous Lmnb1 depletion favors NSC differentiation into glial fibrillar acidic protein (GFAP)-immunoreactive cells over neurons, while overexpression of human Lamin B1 (LMNB1) increases the proportion of neurons. In Lmnb1-null embryos, neurogenesis is reduced, while in vivo Lmnb1 silencing in mouse embryonic brain by in utero electroporation of a specific Lmnb1 sh-RNA results in aberrant cortical positioning of neurons and increased expression of the astrocytic marker GFAP in the cortex of 7-day old pups. Together, these results indicate that finely tuned levels of Lamin B1 are required for NSC differentiation into neurons, proper expression of the astrocytic marker GFAP and corticogenesis.
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Affiliation(s)
- Sameehan Mahajani
- Dept. of Neuroscience and Brain Technologies, Istituto Italiano di Tecnologia, Genova, Italy
- Universitaetsmedizin Goettingen, Waldweg 33, Goettingen, 37073, Germany
| | - Caterina Giacomini
- Dept. of Neuroscience and Brain Technologies, Istituto Italiano di Tecnologia, Genova, Italy
- Division of Cancer Studies, King's College London, New Hunt's House, Guy's Campus, London, SE1 1UL, UK
| | - Federica Marinaro
- Dept. of Neuroscience and Brain Technologies, Istituto Italiano di Tecnologia, Genova, Italy
| | | | - Andrea Contestabile
- Dept. of Neuroscience and Brain Technologies, Istituto Italiano di Tecnologia, Genova, Italy
| | - Laura Gasparini
- Dept. of Neuroscience and Brain Technologies, Istituto Italiano di Tecnologia, Genova, Italy.
- Abbvie Deutschland GmbH & Co, Knollstr, Ludwigshafen, 67061, Germany.
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17
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Shen Z, Li X, Bao X, Wang R. Microglia-targeted stem cell therapies for Alzheimer disease: A preclinical data review. J Neurosci Res 2017. [PMID: 28643422 DOI: 10.1002/jnr.24066] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Alzheimer disease (AD) is a severe, life-threatening illness characterized by gradual memory loss. The classic histological features of AD include extracellular formation of β-amyloid plaques (Aβ), intracellular neurofibrillary tangles (NFT), and synaptic loss. Recently, accumulated evidence has confirmed the critical role of microglia in the development and exacerbation of AD. When Aβ forms deposits, microglia quickly respond to restore brain physiology by activating a series of repair mechanisms. However, prolonged microglial activation is considered detrimental and may aggravate AD progression. To date, there are no curative therapies for AD. The advent of stem cell transplantation offers novel strategies to treat AD in animal models. Furthermore, studies have reported that transplanted stem cells might ameliorate AD symptoms by regulating microglial functions, from detrimental to protective. This review focuses on the crucial functions of microglia in AD and examines the reactions of microglia to transplanted stem cells.
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Affiliation(s)
- Zhiwei Shen
- Department of Neurosurgery, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Xueyuan Li
- Department of Neurosurgery, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Xinjie Bao
- Department of Neurosurgery, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Renzhi Wang
- Department of Neurosurgery, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
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18
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Dai B, Lei C, Lin R, Tao L, Bin Y, Peng H, Lei B. Activation of liver X receptor α protects amyloid β 1-40 induced inflammatory and senescent responses in human retinal pigment epithelial cells. Inflamm Res 2017; 66:523-534. [PMID: 28361293 DOI: 10.1007/s00011-017-1036-4] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2016] [Revised: 03/09/2017] [Accepted: 03/13/2017] [Indexed: 12/21/2022] Open
Abstract
OBJECTIVE To investigate whether activation of the liver X receptors (LXRs) inhibits amyloid β1-40 (Aβ1-40) induced inflammatory and senescent responses in human retinal pigment epithelial (RPE) cells. MATERIALS AND METHODS Confluent cultures of human primary RPE and ARPE-19 cells pretreated with 5 μΜ of TO901317 (TO90), a synthetic agonist of LXR, or vehicle were incubated with 1 μΜ of Aβ1-40 or Aβ40-1. The optimum concentrations of Aβ1-40 and TO90 were determined by cell viability assay. Pro-inflammatory cytokines IL-6, IL-8, MCP-1 were detected by real-time polymerase chain reaction (PCR) and enzyme-linked immunosorbent assay (ELISA). Expression and localization of an aging protein p16INK4a (p16) were analyzed by western blotting and immunofluorescence. Expressions of LXRs and one of their target genes ATP-binding cassette transporter A1 (ABCA1) were examined by real-time PCR and western blotting. Phosphorylated transcription inhibition factor-κB-α (p-IκB-α) was assessed by western blotting. RESULTS A negative linear relationship between the Aβ1-40 concentration and the cell viability was evident, indicating Aβ1-40 decreased ARPE-19 cell viability in a dose-dependent manner. Aβ1-40 enhanced the expression of IL-6, IL-8, MCP-1 as well as p16 in both RPE cell lines at both mRNA and protein levels, whereas TO90 counteracted the detrimental effects. TO90 upregulated the expression of LXRα and its target gene ABCA1, but it did not affect the expression of LXRβ. Meanwhile, TO90 inhibited the phosphorylation of IκB-α mediated by Aβ1-40 stimulation. CONCLUSION Activation of the LXRα-ABCA1 axis may alleviate Aβ1-40 induced inflammatory and senescent responses in RPE cells. The beneficial effect appears associated with the inhibition of the NF-κB signaling pathway.
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Affiliation(s)
- Bingling Dai
- Chongqing Key Laboratory of Ophthalmology, Chongqing Eye Institute, The First Affiliated Hospital of Chongqing Medical University, 1 Youyi Road, Chongqing, 400016, China
| | - Chunyan Lei
- Chongqing Key Laboratory of Ophthalmology, Chongqing Eye Institute, The First Affiliated Hospital of Chongqing Medical University, 1 Youyi Road, Chongqing, 400016, China
| | - Ru Lin
- Chongqing Key Laboratory of Ophthalmology, Chongqing Eye Institute, The First Affiliated Hospital of Chongqing Medical University, 1 Youyi Road, Chongqing, 400016, China
| | - Lifei Tao
- Chongqing Key Laboratory of Ophthalmology, Chongqing Eye Institute, The First Affiliated Hospital of Chongqing Medical University, 1 Youyi Road, Chongqing, 400016, China
| | - Yue Bin
- Chongqing Key Laboratory of Ophthalmology, Chongqing Eye Institute, The First Affiliated Hospital of Chongqing Medical University, 1 Youyi Road, Chongqing, 400016, China
| | - Hui Peng
- Chongqing Key Laboratory of Ophthalmology, Chongqing Eye Institute, The First Affiliated Hospital of Chongqing Medical University, 1 Youyi Road, Chongqing, 400016, China.
| | - Bo Lei
- Chongqing Key Laboratory of Ophthalmology, Chongqing Eye Institute, The First Affiliated Hospital of Chongqing Medical University, 1 Youyi Road, Chongqing, 400016, China.
- Henan Provincial People's Hospital, Henan Eye Institute, Henan Eye Hospital, People's Hospital of Zhengzhou University, 7 Weiwu Road, Zhengzhou, 450003, China.
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19
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Zheng JY, Liang KS, Wang XJ, Zhou XY, Sun J, Zhou SN. Chronic Estradiol Administration During the Early Stage of Alzheimer's Disease Pathology Rescues Adult Hippocampal Neurogenesis and Ameliorates Cognitive Deficits in Aβ 1-42 Mice. Mol Neurobiol 2016; 54:7656-7669. [PMID: 27838872 DOI: 10.1007/s12035-016-0181-z] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2016] [Accepted: 09/28/2016] [Indexed: 11/26/2022]
Abstract
Alzheimer's disease (AD) is the leading cause of dementia and has become an important public health concern. Accumulating evidence indicates that estradiol can both facilitate and impair memory-related processes and, as a result, the precise nature of the role that estradiol plays during AD pathology remains elusive. Therefore, the present study established a mouse model of AD using stereotactic brain injection of Aβ1-42 in which the mice were bilaterally ovariectomized to investigate the effects of 17β-estradiol (E2) treatment during different stages of the AD process (early and late stages). The cognitive deficits associated with this AD model were significantly ameliorated, and there was a significant increase in hippocampal neurogenesis in Aβ1-42 mice that received E2 treatment during the early stage of AD pathology. On the other hand, Aβ1-42 mice that received E2 treatment during the late stage of AD pathology did not exhibit any improvements in cognitive function or hippocampal neurogenesis. To reveal the mechanisms, underlying these effects, levels of oxidative stress, activity in death-associated pathways, gliosis, and synaptic function were assessed in the hippocampus. The Aβ1-42 mice that received E2 treatment during the early stage of AD pathology exhibited significant reductions in the production of nitric oxide (NO) and reactive oxygen species (ROS), a marked decrease in the activation of Cytochrome-c/Bax/Bcl-2/caspase-3 pathway, a notable decrease in the level of gliosis a significant increase in the number of synapses (ultrastructural investigation), and a marked upregulation in synaptic function-related proteins compared to mice that received E2 treatment during the late stage of AD pathology. Taken together, these findings indicate that E2 treatment during the early stage of AD pathology might be an efficient approach to ameliorate the development of this disease.
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Affiliation(s)
- Jin-Yu Zheng
- Department of Neurosurgery, The Affiliated Huai'an Hospital of Xuzhou Medical College, No. 62 South Huaihai Road, Huai'an, Jiangsu Province, 223002, People's Republic of China
| | - Ke-Shan Liang
- Department of Neurology, Qilu Hospital of Shandong University and Brain Science Research Institute, Shandong University, No. 107 Wenhuaxi Road, Jinan, Shandong, 250012, People's Republic of China
- Department of Neurology, Pingyi Branch of Qilu Hospital, Shandong University, No. 07 Jinhua Road, Pingyi, Shandong Province, 273300, People's Republic of China
| | - Xian-Jun Wang
- Department of Neurology, Linyi People's Hospital, No. 49 Yizhou Road, Linyi, Shandong, 276000, People's Republic of China
| | - Xue-Ying Zhou
- Department of Neurology, Shangdong University of Traditional Chinese Medicine, Jinan, Shandong, 250031, China
| | - Jian Sun
- Department of Anesthesiology, Maternal and Child Health Hospital of Huai'an, No. 104 South Renmin, Huai'an, Jiangsu Province, 223002, China.
| | - Sheng-Nian Zhou
- Department of Neurology, Qilu Hospital of Shandong University and Brain Science Research Institute, Shandong University, No. 107 Wenhuaxi Road, Jinan, Shandong, 250012, People's Republic of China.
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Abstract
UNLABELLED Tauopathies are neurodegenerative diseases characterized by intraneuronal inclusions of hyperphosphorylated tau protein and abnormal expression of brain-derived neurotrophic factor (BDNF), a key modulator of neuronal survival and function. The severity of both these pathological hallmarks correlate with the degree of cognitive impairment in patients. However, how tau pathology specifically modifies BDNF signaling and affects neuronal function during early prodromal stages of tauopathy remains unclear. Here, we report that the mild tauopathy developing in retinal ganglion cells (RGCs) of the P301S tau transgenic (P301S) mouse induces functional retinal changes by disrupting BDNF signaling via the TrkB receptor. In adult P301S mice, the physiological visual response of RGCs to pattern light stimuli and retinal acuity decline significantly. As a consequence, the activity-dependent secretion of BDNF in the vitreous is impaired in P301S mice. Further, in P301S retinas, TrkB receptors are selectively upregulated, but uncoupled from downstream extracellular signal-regulated kinase (ERK) 1/2 signaling. We also show that the impairment of TrkB signaling is triggered by tau pathology and mediates the tau-induced dysfunction of visual response. Overall our results identify a neurotrophin-mediated mechanism by which tau induces neuronal dysfunction during prodromal stages of tauopathy and define tau-driven pathophysiological changes of potential value to support early diagnosis and informed therapeutic decisions. SIGNIFICANCE STATEMENT This work highlights the potential molecular mechanisms by which initial tauopathy induces neuronal dysfunction. Combining clinically used electrophysiological techniques (i.e., electroretinography) and molecular analyses, this work shows that in a relevant model of early tauopathy, the retina of the P301S mutant human tau transgenic mouse, mild tau pathology results in functional changes of neuronal activity, likely due to selective impairment of brain-derived neurotrophic factor signaling via its receptor, TrkB. These findings may have important translational implications for early diagnosis in a subset of Alzheimer's disease patients with early visual symptoms and emphasize the need to clarify the pathophysiological changes associated with distinct tauopathy stages to support informed therapeutic decisions and guide drug discovery.
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21
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Golde TE. Overcoming translational barriers impeding development of Alzheimer's disease modifying therapies. J Neurochem 2016; 139 Suppl 2:224-236. [PMID: 27145445 DOI: 10.1111/jnc.13583] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2015] [Revised: 01/25/2016] [Accepted: 02/12/2016] [Indexed: 12/21/2022]
Abstract
It has now been ~ 30 years since the Alzheimer's disease (AD) research entered what may be termed the 'molecular era' that began with the identification of the amyloid β protein (Aβ) as the primary component of amyloid within senile plaques and cerebrovascular amyloid and the microtubule-associated protein tau as the primary component of neurofibrillary tangles in the AD brain. These pivotal discoveries and the subsequent genetic, pathological, and modeling studies supporting pivotal roles for tau and Aβ aggregation and accumulation have provided firm rationale for a new generation of AD therapies designed not to just provide symptomatic benefit, but as disease modifying agents that would slow or even reverse the disease course. Indeed, over the last 20 years numerous therapeutic strategies for disease modification have emerged, been preclinically validated, and advanced through various stages of clinical testing. Unfortunately, no therapy has yet to show significant clinical disease modification. In this review, I describe 10 translational barriers to successful disease modification, highlight current efforts addressing some of these barriers, and discuss how the field could focus future efforts to overcome barriers that are not major foci of current research efforts. Seminal discoveries made over the past 25 years have provided firm rationale for a new generation of Alzheimer's disease (AD) therapies designed as disease modifying agents that would slow or even reverse the disease course. Unfortunately, no therapy has yet to show significant clinical disease modification. In this review, I describe 10 translational barriers to successful AD disease modification, highlight current efforts addressing some of these barriers, and discuss how the field could focus future efforts to overcome these barriers. This article is part of the 60th Anniversary special issue.
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Affiliation(s)
- Todd E Golde
- Department of Neuroscience, Center for Translational Research in Neurodegenerative Disease, McKnight Brain Institute, College of Medicine, University of Florida, Gainesville, Florida, USA.
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Sengupta U, Nilson AN, Kayed R. The Role of Amyloid-β Oligomers in Toxicity, Propagation, and Immunotherapy. EBioMedicine 2016; 6:42-49. [PMID: 27211547 PMCID: PMC4856795 DOI: 10.1016/j.ebiom.2016.03.035] [Citation(s) in RCA: 484] [Impact Index Per Article: 60.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2015] [Revised: 03/03/2016] [Accepted: 03/21/2016] [Indexed: 02/06/2023] Open
Abstract
The incidence of Alzheimer's disease (AD) is growing every day and finding an effective treatment is becoming more vital. Amyloid-β (Aβ) has been the focus of research for several decades. The recent shift in the Aβ cascade hypothesis from all Aβ to small soluble oligomeric intermediates is directing the search for therapeutics towards the toxic mediators of the disease. Targeting the most toxic oligomers may prove to be an effective treatment by preventing their spread. Specific targeting of oligomers has been shown to protect cognition in rodent models. Additionally, the heterogeneity of research on Aβ oligomers may seem contradictory until size and conformation are taken into account. In this review, we will discuss Aβ oligomers and their toxicity in relation to size and conformation as well as their influence on inflammation and the potential of Aβ oligomer immunotherapy.
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Affiliation(s)
- Urmi Sengupta
- Mitchell Center for Neurodegenerative Diseases, University of Texas Medical Branch, Galveston, TX 77555, USA; Department of Neurology, University of Texas Medical Branch, Galveston, TX 77555, USA; Department of Neuroscience and Cell Biology, University of Texas Medical Branch, Galveston, TX 77555, USA
| | - Ashley N Nilson
- Mitchell Center for Neurodegenerative Diseases, University of Texas Medical Branch, Galveston, TX 77555, USA; Department of Neurology, University of Texas Medical Branch, Galveston, TX 77555, USA; Department of Neuroscience and Cell Biology, University of Texas Medical Branch, Galveston, TX 77555, USA
| | - Rakez Kayed
- Mitchell Center for Neurodegenerative Diseases, University of Texas Medical Branch, Galveston, TX 77555, USA; Department of Neurology, University of Texas Medical Branch, Galveston, TX 77555, USA; Department of Neuroscience and Cell Biology, University of Texas Medical Branch, Galveston, TX 77555, USA; Sealy Center for Vaccine Development, University of Texas Medical Branch, Galveston, TX 77555, USA.
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23
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Barini E, Antico O, Zhao Y, Asta F, Tucci V, Catelani T, Marotta R, Xu H, Gasparini L. Metformin promotes tau aggregation and exacerbates abnormal behavior in a mouse model of tauopathy. Mol Neurodegener 2016; 11:16. [PMID: 26858121 PMCID: PMC4746897 DOI: 10.1186/s13024-016-0082-7] [Citation(s) in RCA: 90] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2015] [Accepted: 02/01/2016] [Indexed: 11/10/2022] Open
Abstract
Background Alzheimer disease (AD) and other tauopathies develop cerebral intracellular inclusions of hyperphosphorylated tau. Epidemiological and experimental evidence suggests a clear link between type 2 diabetes mellitus and AD. In AD animal models, tau pathology is exacerbated by metabolic comorbidities, such as insulin resistance and diabetes. Within this context, anitidiabetic drugs, including the widely-prescribed insulin-sensitizing drug metformin, are currently being investigated for AD therapy. However, their efficacy for tauopathy in vivo has not been tested. Results Here, we report that in the P301S mutant human tau (P301S) transgenic mouse model of tauopathy, chronic administration of metformin exerts paradoxical effects on tau pathology. Despite reducing tau phosphorylation in the cortex and hippocampus via AMPK/mTOR and PP2A, metformin increases insoluble tau species (including tau oligomers) and the number of inclusions with β-sheet aggregates in the brain of P301S mice. In addition, metformin exacerbates hindlimb atrophy, increases P301S hyperactive behavior, induces tau cleavage by caspase 3 and disrupts synaptic structures. Conclusions These findings indicate that metformin pro-aggregation effects mitigate the potential benefits arising from its dephosphorylating action, possibly leading to an overall increase of the risk of tauopathy in elderly diabetic patients. Electronic supplementary material The online version of this article (doi:10.1186/s13024-016-0082-7) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Erica Barini
- Department of Neuroscience and Brain Technologies, Istituto Italiano di Tecnologia, Via Morego 30, Genoa, Italy
| | - Odetta Antico
- Department of Neuroscience and Brain Technologies, Istituto Italiano di Tecnologia, Via Morego 30, Genoa, Italy
| | - Yingjun Zhao
- Fujian Provincial Key Laboratory of Neurodegenerative Disease and Aging Research, Institute of Neuroscience, College of Medicine, Xiamen University, Xiamen, Fujian, 361102, China.,Degenerative Diseases Program, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, CA, 92037, USA
| | - Francesco Asta
- Department of Neuroscience and Brain Technologies, Istituto Italiano di Tecnologia, Via Morego 30, Genoa, Italy
| | - Valter Tucci
- Department of Neuroscience and Brain Technologies, Istituto Italiano di Tecnologia, Via Morego 30, Genoa, Italy
| | - Tiziano Catelani
- Nanochemistry Department, Electron Microscopy Lab, Istituto Italiano di Tecnologia, Via Morego 30, Genoa, Italy
| | - Roberto Marotta
- Nanochemistry Department, Electron Microscopy Lab, Istituto Italiano di Tecnologia, Via Morego 30, Genoa, Italy
| | - Huaxi Xu
- Fujian Provincial Key Laboratory of Neurodegenerative Disease and Aging Research, Institute of Neuroscience, College of Medicine, Xiamen University, Xiamen, Fujian, 361102, China.,Degenerative Diseases Program, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, CA, 92037, USA
| | - Laura Gasparini
- Department of Neuroscience and Brain Technologies, Istituto Italiano di Tecnologia, Via Morego 30, Genoa, Italy. .,Present Address: AbbVie Deutschland GmbH &Co. KG, Knollstr., 67061, Ludwigshafen, Germany.
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24
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Li Y, Du X, Pei G, Du J, Zhao J. β-Arrestin1 regulates the morphology and dynamics of microglia in zebrafish in vivo. Eur J Neurosci 2015; 43:131-8. [PMID: 26354363 DOI: 10.1111/ejn.13065] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2015] [Revised: 09/02/2015] [Accepted: 09/04/2015] [Indexed: 01/24/2023]
Abstract
Microglia are the primary immune cells in the central nervous system. Microglia typically exist in a 'resting' state in the healthy brain, with ramified processes dynamically exploring the surrounding microenvironment. They become 'activated' under pathological conditions with marked changes in morphology. However, the regulation of their morphology dynamics remains poorly understood. Here, using in vivo time-lapse imaging and three-dimensional morphology analysis of microglia in intact zebrafish larvae, we found that β-arrestin1, a multifunctional protein involved in various signal transductions, cell-autonomously regulated the microglial morphology. Knockdown of β-arrestin1 increased the volume size and process number of microglia but reduced the deformation speed in the resting state. Meanwhile, β-arrestin1 down-regulation led to a high frequency of phagocytic behaviour of microglia. These defects were partially rescued by over-expressing human β-arrestin1 in microglia. Our study indicated that microglial dynamics in the resting state can be regulated cell-autonomously by β-arrestin1 signalling.
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Affiliation(s)
- Yuanyuan Li
- State Key Laboratory of Cell Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Graduate School of the Chinese Academy of Sciences, Chinese Academy of Sciences, Shanghai, 200031, China
| | - Xufei Du
- Institute of Neuroscience and State Key Laboratory of Neuroscience, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, China
| | - Gang Pei
- State Key Laboratory of Cell Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Graduate School of the Chinese Academy of Sciences, Chinese Academy of Sciences, Shanghai, 200031, China
| | - Jiulin Du
- Institute of Neuroscience and State Key Laboratory of Neuroscience, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, China
| | - Jian Zhao
- State Key Laboratory of Cell Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Graduate School of the Chinese Academy of Sciences, Chinese Academy of Sciences, Shanghai, 200031, China.,Translational Medical Center for Stem Cell Therapy, Shanghai East Hospital, School of Medicine, Tongji University, Shanghai, China
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25
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Pomilio C, Pavia P, Gorojod RM, Vinuesa A, Alaimo A, Galvan V, Kotler ML, Beauquis J, Saravia F. Glial alterations from early to late stages in a model of Alzheimer's disease: Evidence of autophagy involvement in Aβ internalization. Hippocampus 2015; 26:194-210. [PMID: 26235241 DOI: 10.1002/hipo.22503] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/28/2015] [Indexed: 01/19/2023]
Abstract
Alzheimer's disease (AD) is a progressive neurodegenerative disease without effective therapy. Brain amyloid deposits are classical histopathological hallmarks that generate an inflammatory reaction affecting neuronal and glial function. The identification of early cell responses and of brain areas involved could help to design new successful treatments. Hence, we studied early alterations of hippocampal glia and their progression during the neuropathology in PDAPP-J20 transgenic mice, AD model, at 3, 9, and 15 months (m) of age. At 3 m, before deposits formation, microglial Iba1+ cells from transgenic mice already exhibited signs of activation and larger soma size in the hilus, alterations appearing later on stratum radiatum. Iba1 immunohistochemistry revealed increased cell density and immunoreactive area in PDAPP mice from 9 m onward selectively in the hilus, in coincidence with prominent amyloid Congo red + deposition. At pre-plaque stages, GFAP+ astroglia showed density alterations while, at an advanced age, the presence of deposits was associated with important glial volume changes and apparently being intimately involved in amyloid degradation. Astrocytes around plaques were strongly labeled for LC3 until 15 m in Tg mice, suggestive of increased autophagic flux. Moreover, β-Amyloid fibrils internalization by astrocytes in in vitro conditions was dependent on autophagy. Co-localization of Iba1 with ubiquitin or p62 was exclusively found in microglia contacting deposits from 9 m onward, suggesting torpid autophagy. Our work characterizes glial changes at early stages of the disease in PDAPP-J20 mice, focusing on the hilus as an especially susceptible hippocampal subfield, and provides evidence that glial autophagy could play a role in amyloid processing at advanced stages.
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Affiliation(s)
- Carlos Pomilio
- Departamento De Quimica Biologica, Facultad De Ciencias Exactas Y Naturales, Universidad De Buenos Aires, Instituto De Biologia Y Medicina Experimental Conicet, Buenos Aires, Argentina
| | - Patricio Pavia
- Departamento De Quimica Biologica, Facultad De Ciencias Exactas Y Naturales, Universidad De Buenos Aires, Instituto De Biologia Y Medicina Experimental Conicet, Buenos Aires, Argentina
| | - Roxana Mayra Gorojod
- Departamento De Quimica Biologica, Facultad De Ciencias Exactas Y Naturales, Universidad De Buenos Aires, IQUIBICEN-Conicet, Buenos Aires, Argentina
| | - Angeles Vinuesa
- Departamento De Quimica Biologica, Facultad De Ciencias Exactas Y Naturales, Universidad De Buenos Aires, Instituto De Biologia Y Medicina Experimental Conicet, Buenos Aires, Argentina
| | - Agustina Alaimo
- Departamento De Quimica Biologica, Facultad De Ciencias Exactas Y Naturales, Universidad De Buenos Aires, IQUIBICEN-Conicet, Buenos Aires, Argentina
| | - Veronica Galvan
- Department of Physiology, Barshop Institute for Longevity and Aging Studies, University of Texas Health Science Center, San Antonio, Texas
| | - Monica Lidia Kotler
- Departamento De Quimica Biologica, Facultad De Ciencias Exactas Y Naturales, Universidad De Buenos Aires, IQUIBICEN-Conicet, Buenos Aires, Argentina
| | - Juan Beauquis
- Departamento De Quimica Biologica, Facultad De Ciencias Exactas Y Naturales, Universidad De Buenos Aires, Instituto De Biologia Y Medicina Experimental Conicet, Buenos Aires, Argentina
| | - Flavia Saravia
- Departamento De Quimica Biologica, Facultad De Ciencias Exactas Y Naturales, Universidad De Buenos Aires, Instituto De Biologia Y Medicina Experimental Conicet, Buenos Aires, Argentina
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26
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Zhao Y, Lukiw WJ. Microbiome-generated amyloid and potential impact on amyloidogenesis in Alzheimer's disease (AD). JOURNAL OF NATURE AND SCIENCE 2015; 1:e138. [PMID: 26097896 PMCID: PMC4469284] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
According to the 'amyloid cascade hypothesis of Alzheimer's disease' first proposed about 16 years ago, the accumulation of Aβ peptides in the human central nervous system (CNS) is the primary influence driving Alzheimer's disease (AD) pathogenesis, and Aβ peptide accretion is the result of an imbalance between Aβ peptide production and clearance. In the last 18 months multiple laboratories have reported two particularly important observations: (i) that because the microbes of the human microbiome naturally secrete large amounts of amyloid, lipopolysaccharides (LPS) and other related pro-inflammatory pathogenic signals, these may contribute to both the systemic and CNS amyloid burden in aging humans; and (ii) that the clearance of Aβ peptides appears to be intrinsically impaired by deficits in the microglial plasma-membrane enriched triggering receptor expressed in microglial/myeloid-2 cells (TREM2). This brief general commentary-perspective paper: (i) will highlight some of these very recent findings on microbiome-secreted amyloids and LPS and the potential contribution of these microbial-derived pro-inflammatory and neurotoxic exudates to age-related inflammatory and AD-type neurodegeneration in the host; and (ii) will discuss the contribution of a defective microglial-based TREM2 transmembrane sensor-receptor system to amyloidogenesis in AD that is in contrast to the normal, homeostatic clearance of Aβ peptides from the human CNS.
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Affiliation(s)
- Yuhai Zhao
- LSU Neuroscience Center, Louisiana State University Health Sciences Center, 2020 Gravier Street, Suite 904, New Orleans, LA 70112, USA
- Department of Cell Biology and Anatomy, Louisiana State University Health Sciences Center, 2020 Gravier Street, Suite 904, New Orleans, LA 70112, USA
| | - Walter J. Lukiw
- LSU Neuroscience Center, Louisiana State University Health Sciences Center, 2020 Gravier Street, Suite 904, New Orleans, LA 70112, USA
- Department of Ophthalmology, Louisiana State University Health Sciences Center, 2020 Gravier Street, Suite 904, New Orleans, LA 70112, USA
- Department of Neurology, Louisiana State University Health Sciences Center, 2020 Gravier Street, Suite 904, New Orleans, LA 70112, USA
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27
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Nichols MR, Colvin BA, Hood EA, Paranjape GS, Osborn DC, Terrill-Usery SE. Biophysical Comparison of Soluble Amyloid-β(1–42) Protofibrils, Oligomers, and Protofilaments. Biochemistry 2015; 54:2193-204. [DOI: 10.1021/bi500957g] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Affiliation(s)
- Michael R. Nichols
- Department of Chemistry and
Biochemistry and Center for Nanoscience, University of Missouri—St. Louis, One University Boulevard, St. Louis, Missouri 63121, United States
| | - Benjamin A. Colvin
- Department of Chemistry and
Biochemistry and Center for Nanoscience, University of Missouri—St. Louis, One University Boulevard, St. Louis, Missouri 63121, United States
| | - Elizabeth A. Hood
- Department of Chemistry and
Biochemistry and Center for Nanoscience, University of Missouri—St. Louis, One University Boulevard, St. Louis, Missouri 63121, United States
| | - Geeta S. Paranjape
- Department of Chemistry and
Biochemistry and Center for Nanoscience, University of Missouri—St. Louis, One University Boulevard, St. Louis, Missouri 63121, United States
| | - David C. Osborn
- Department of Chemistry and
Biochemistry and Center for Nanoscience, University of Missouri—St. Louis, One University Boulevard, St. Louis, Missouri 63121, United States
| | - Shana E. Terrill-Usery
- Department of Chemistry and
Biochemistry and Center for Nanoscience, University of Missouri—St. Louis, One University Boulevard, St. Louis, Missouri 63121, United States
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28
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Zhao Y, Dua P, Lukiw WJ. Microbial Sources of Amyloid and Relevance to Amyloidogenesis and Alzheimer's Disease (AD). JOURNAL OF ALZHEIMER'S DISEASE & PARKINSONISM 2015; 5:177. [PMID: 25977840 PMCID: PMC4428612 DOI: 10.4172/2161-0460.1000177] [Citation(s) in RCA: 78] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Since the inception of the human microbiome project (HMP) by the US National Institutes of Health (NIH) in 2007 there has been a keen resurgence in our recognition of the human microbiome and its contribution to development, immunity, neurophysiology, metabolic and nutritive support to central nervous system (CNS) health and disease. What is not generally appreciated is that (i) the ~1014 microbial cells that comprise the human microbiome outnumber human host cells by approximately one hundred-to-one; (ii) together the microbial genes of the microbiome outnumber human host genes by about one hundred-and-fifty to one; (iii) collectively these microbes constitute the largest 'diffuse organ system' in the human body, more metabolically active than the liver; strongly influencing host nutritive-, innate-immune, neuroinflammatory-, neuromodulatory- and neurotransmission-functions; and (iv) that these microbes actively secrete highly complex, immunogenic mixtures of lipopolysaccharide (LPS) and amyloid from their outer membranes into their immediate environment. While secreted LPS and amyloids are generally quite soluble as monomers over time they form into highly insoluble fibrous protein aggregates that are implicated in the progressive degenerative neuropathology of several common, age-related disorders of the human CNS including Alzheimer's disease (AD). This general commentary-perspective paper will highlight some recent findings on microbial-derived secreted LPS and amyloids and the potential contribution of these neurotoxic and proinflammatory microbial exudates to age-related inflammatory amyloidogenesis and neurodegeneration, with specific reference to AD wherever possible.
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Affiliation(s)
- Y Zhao
- LSU Neuroscience Center, Louisiana State University Health Sciences Center, 2020 Gravier Street, New Orleans LA 70112 USA ; Department of Cell Biology and Anatomy, Louisiana State University Health Sciences Center, 1901 Perdido Street, New Orleans LA 70112 USA
| | - P Dua
- Department of Health Information Management, Louisiana State University Ruston LA 71270 USA
| | - W J Lukiw
- LSU Neuroscience Center, Louisiana State University Health Sciences Center, 2020 Gravier Street, New Orleans LA 70112 USA ; Department of Ophthalmology, Louisiana State University Health Sciences Center, 533 Bolivar Street, New Orleans LA 70112 USA ; Department of Neurology, Louisiana State University Health Sciences Center, 1542 Tulane Avenue, New Orleans LA 70112 USA
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29
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Hill JM, Lukiw WJ. Microbial-generated amyloids and Alzheimer's disease (AD). Front Aging Neurosci 2015; 7:9. [PMID: 25713531 PMCID: PMC4322713 DOI: 10.3389/fnagi.2015.00009] [Citation(s) in RCA: 115] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2014] [Accepted: 01/21/2015] [Indexed: 01/27/2023] Open
Affiliation(s)
- James M Hill
- Louisiana State University Neuroscience Center, Louisiana State University Health Sciences Center New Orleans, LA, USA ; Departments of Ophthalmology, Louisiana State University Health Sciences Center New Orleans, LA, USA ; Microbiology, Louisiana State University Health Sciences Center New Orleans, LA, USA ; Pharmacology, Louisiana State University Health Sciences Center New Orleans, LA, USA
| | - Walter J Lukiw
- Louisiana State University Neuroscience Center, Louisiana State University Health Sciences Center New Orleans, LA, USA ; Departments of Ophthalmology, Louisiana State University Health Sciences Center New Orleans, LA, USA ; Neurology, Louisiana State University Health Sciences Center New Orleans, LA, USA
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30
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Abstract
Alzheimer's disease (AD) is typified by a robust microglial-mediated inflammatory response within the brain. Indeed, microglial accumulation around plaques in AD is one of the classical hallmarks of the disease pathology. Although microglia have the capacity to remove β-amyloid deposits and alleviate disease pathology, they fail to do so. Instead, they become chronically activated and promote inflammation-mediated impairment of cognition and cytotoxicity. However, if microglial function could be altered to engage their phagocytic response, promote their tissue maintenance functions, and prevent release of factors that promote tissue damage, this could provide therapeutic benefit. This review is focused on the current knowledge of microglial homeostatic mechanisms in AD, and mechanisms involved in the regulation of microglial phenotype in this context.
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Affiliation(s)
- Tarja M Malm
- A.I. Virtanen Institute for Molecular Sciences, University of Eastern Finland, P.O. Box 1627, 70211, Kuopio, Finland,
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