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Pucci IM, Aguiar AF, Pucci RM, Casonatto J, Borghi SM. Systematic review and meta-analysis of randomized controlled trials on the effects of exercise interventions on amyloid beta levels in humans. Exp Brain Res 2024; 242:1011-1024. [PMID: 38551691 DOI: 10.1007/s00221-024-06821-y] [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: 09/27/2023] [Accepted: 03/13/2024] [Indexed: 06/05/2024]
Abstract
Alzheimer's disease (AD) represents the most common type of dementia. A crucial mechanism attributed to its development is amyloid beta (Aβ) dynamics dysregulation. The extent to which exercise can modulate this phenomenon is uncertain. The aim of this study was to summarize the existing literature evaluating this issue. A comprehensive systematic search was performed in Pubmed, Scopus, Embase, Web of Science, and SciELO databases and completed in August 2023, aiming to identify randomized controlled trials investigating the effect of exercise upon Aβ-related pathology. The keywords "exercise" and "amyloid beta", as well as all their equivalents and similar terms, were used. For the analysis, the negative or positive dementia status of the subjects was initially considered and then the soluble amyloid precursor protein (sAPP) components and Aβ fragments separately. A meta-analysis was performed and involved eight studies (moderate-to-high quality) and 644 assessments, which were 297 for control and 347 for exercise. No overall effect favoring exercise interventions was observed for both negative (SMD95%=0,286 [-0,131; 0,704]; p = 0,179) or positive AD dementia status (SMD95%=0,110 [-0,155; 0,375]; p = 0,416). The absence of an overall effect favoring exercise interventions was also found for Aβ peptides (SMD95%=0,226 [-0,028; 0,480]; p = 0,081) and for sAPP components (SMD95%=-0,038 50 [-0,472; 0,396]; p = 0,863) levels. Our findings suggest that exercise interventions do not improve Aβ-related pathology in both healthy individuals and individuals with dementia (SMD95%=0,157 [-0,059; 0,373]; p = 0,155), indicating that the beneficial effects of exercise for AD reported in previous studies are related to other mechanistic effects rather than direct amyloid effects (PROSPERO registration number: CRD42023426912).
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Affiliation(s)
- Isabela Mayer Pucci
- Center for Research in Health Sciences, Universidade Norte do Paraná (Unopar), Paraná, Londrina, 86041-140, Brazil
| | - Andreo F Aguiar
- Center for Research in Health Sciences, Universidade Norte do Paraná (Unopar), Paraná, Londrina, 86041-140, Brazil
| | - Rodrigo M Pucci
- Universidade Federal do Mato Grosso do Sul (UFMS), Campo Grande, Mato Grosso do Sul, Cuiabá, 79070-900, Brazil
| | - Juliano Casonatto
- Center for Research in Health Sciences, Universidade Norte do Paraná (Unopar), Paraná, Londrina, 86041-140, Brazil
| | - Sergio Marques Borghi
- Center for Research in Health Sciences, Universidade Norte do Paraná (Unopar), Paraná, Londrina, 86041-140, Brazil.
- Department of Pathology, Biological Sciences Center, Universidade Estadual de Londrina (UEL), Paraná State, Londrina, 86057-970, Brazil.
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Hossen F, Geng X, Sun GY, Yao X, Lee JC. Oligomeric Amyloid-β and Tau Alter Cell Adhesion Properties and Induce Inflammatory Responses in Cerebral Endothelial Cells Through the RhoA/ROCK Pathway. Mol Neurobiol 2024:10.1007/s12035-024-04138-z. [PMID: 38561558 DOI: 10.1007/s12035-024-04138-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2023] [Accepted: 03/19/2024] [Indexed: 04/04/2024]
Abstract
Dysfunction of cerebral endothelial cells (CECs) has been implicated in the pathology of Alzheimer's disease (AD). Despite evidence showing cytotoxic effects of oligomeric amyloid-β (oAβ) and Tau (oTau) in the central nervous system, their direct effects on CECs have not been fully investigated. In this study, we examined the direct effects of oAβ, oTau, and their combination on cell adhesion properties and inflammatory responses in CECs. We found that both oAβ and oTau increased cell stiffness, as well as the p-selectin/Sialyl-LewisX (sLeX) bonding-mediated membrane tether force and probability of adhesion in CECs. Consistent with these biomechanical alterations, treatments with oAβ or oTau also increased actin polymerization and the expression of p-selectin at the cell surface. These toxic oligomeric peptides also triggered inflammatory responses, including upregulations of p-NF-kB p65, IL-1β, and TNF-α. In addition, they rapidly activated the RhoA/ROCK pathway. These biochemical and biomechanical changes were further enhanced by the treatment with the combination of oAβ and oTau, which were significantly suppressed by Fasudil, a specific inhibitor for the RhoA/ROCK pathway. In conclusion, our data suggest that oAβ, oTau, and their combination triggered subcellular mechanical alterations and inflammatory responses in CECs through the RhoA/ROCK pathway.
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Affiliation(s)
- Faruk Hossen
- Richard and Loan Hill Department of Biomedical Engineering, University of Illinois at Chicago, Chicago, IL, 60607, USA
| | - Xue Geng
- Richard and Loan Hill Department of Biomedical Engineering, University of Illinois at Chicago, Chicago, IL, 60607, USA
| | - Grace Y Sun
- Department of Biochemistry, University of Missouri, Columbia, MO, 65211, USA
| | - Xincheng Yao
- Richard and Loan Hill Department of Biomedical Engineering, University of Illinois at Chicago, Chicago, IL, 60607, USA
| | - James C Lee
- Richard and Loan Hill Department of Biomedical Engineering, University of Illinois at Chicago, Chicago, IL, 60607, USA.
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3
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Zhou K, Han J, Wang Y, Xu Y, Zhang Y, Zhu C. The therapeutic potential of bone marrow-derived macrophages in neurological diseases. CNS Neurosci Ther 2022; 28:1942-1952. [PMID: 36066198 PMCID: PMC9627381 DOI: 10.1111/cns.13964] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2022] [Revised: 08/19/2022] [Accepted: 08/22/2022] [Indexed: 02/06/2023] Open
Abstract
Circulating monocytes are precursors of both tissue macrophages and dendritic cells, and they can infiltrate the central nervous system (CNS) where they transform into bone marrow-derived macrophages (BMDMs). BMDMs play essential roles in various CNS diseases, thus modulating BMDMs might be a way to treat these disorders because there are currently no efficient therapeutic methods available for most of these neurological diseases. Moreover, BMDMs can serve as promising gene delivery vehicles following bone marrow transplantation for otherwise incurable genetic CNS diseases. Understanding the distinct roles that BMDMs play in CNS diseases and their potential as gene delivery vehicles may provide new insights and opportunities for using BMDMs as therapeutic targets or delivery vehicles. This review attempts to comprehensively summarize the neurological diseases that might be treated by modulating BMDMs or by delivering gene therapies via BMDMs after bone marrow transplantation.
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Affiliation(s)
- Kai Zhou
- Henan Neurodevelopment Engineering Research Center for ChildrenChildren's Hospital Affiliated to Zhengzhou UniversityZhengzhouChina
| | - Jinming Han
- Department of Neurology, Xuanwu HospitalCapital Medical UniversityBeijingChina
| | - Yafeng Wang
- Henan Neurodevelopment Engineering Research Center for ChildrenChildren's Hospital Affiliated to Zhengzhou UniversityZhengzhouChina,Department of Hematology and OncologyChildren's Hospital Affiliated to Zhengzhou University, Henan, Children's Hospital, Zhengzhou Children's HospitalZhengzhouChina
| | - Yiran Xu
- Henan Key Laboratory of Child Brain Injury and Henan Pediatric Clinical Research CenterThe Third Affiliated Hospital and Institute of Neuroscience, Zhengzhou UniversityZhengzhouChina
| | - Yaodong Zhang
- Henan Neurodevelopment Engineering Research Center for ChildrenChildren's Hospital Affiliated to Zhengzhou UniversityZhengzhouChina
| | - Changlian Zhu
- Henan Key Laboratory of Child Brain Injury and Henan Pediatric Clinical Research CenterThe Third Affiliated Hospital and Institute of Neuroscience, Zhengzhou UniversityZhengzhouChina,Centre for Brain Repair and RehabilitationInstitute of Neuroscience and Physiology, Sahlgrenska Academy, University of GothenburgGothenburgSweden
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4
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Abstract
The accumulation of neurotoxic amyloid-beta (Aβ) in the brain is one of the characteristic hallmarks of Alzheimer's disease (AD). Aβ-peptide brain homeostasis is governed by its production and various clearance mechanisms. The blood-brain barrier provides a large surface area for influx and efflux mechanisms into and out of the brain. Different transporters and receptors have been implicated to play crucial roles in Aβ clearance from brain. Besides Aβ transport, the blood-brain barrier tightly regulates the brain's microenvironment; however, vascular alterations have been shown in patients with AD. Here, we summarize how the blood-brain barrier changes during aging and in disease and focus on recent findings of how the ABC transporter P-glycoprotein (ABCB1/P-gp) and the receptor low-density lipoprotein receptor-related protein 1 (LRP1) play a role in Aβ clearance from brain.
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Chwalisz BK. Cerebral amyloid angiopathy and related inflammatory disorders. J Neurol Sci 2021; 424:117425. [PMID: 33840507 DOI: 10.1016/j.jns.2021.117425] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2020] [Revised: 10/27/2020] [Accepted: 03/24/2021] [Indexed: 11/19/2022]
Abstract
Inflammatory cerebral amyloid angiopathy is a largely reversible inflammatory vasculopathy that develops in an acute or subacute fashion in reaction to amyloid protein deposition in the central nervous system blood vessels. There are two recognized pathologically characterized variants: cerebral amyloid angiopathy-related inflammation (CAAri) and A beta-related angiitis (ABRA). Both variants produce a clinical picture that resembles primary angiitis of the CNS but is distinguished by a characteristic radiologic appearance. Although originally defined as a clinicopathologic diagnosis, it can now often be diagnosed based on clinicoradiologic criteria, though confirmation with brain and meningeal biopsy is still required in some cases. This disorder typically responds to steroids but addition of other immune suppressants may be needed in some cases to control the disease.
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Affiliation(s)
- B K Chwalisz
- Department of Neurology, Massachusetts General Hospital/Harvard Medical School, 15 Parkman Street, Suite 835, Boston, MA 02114, USA; Division of Neuro-Ophthalmology, Department of Ophthalmology, Massachusetts Eye & Ear Infirmary/Harvard Medical School, Boston, MA, USA.
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Austin SA, Katusic ZS. Partial loss of endothelial nitric oxide leads to increased cerebrovascular beta amyloid. J Cereb Blood Flow Metab 2020; 40:392-403. [PMID: 30614363 PMCID: PMC7370614 DOI: 10.1177/0271678x18822474] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Cerebral amyloid angiopathy (CAA) is present in over half of the elderly population and in 80-90% of Alzheimer's disease (AD) patients. CAA is defined by the deposition of beta amyloid (Aβ) in small cerebral arteries and capillaries. Cardiovascular risk factors are associated with an increased incidence of CAA. We utilized 18-month-old endothelial nitric oxide synthase (eNOS) heterozygous knockout (+/-) mice, a clinically relevant model of endothelial dysfunction, to examine the role of endothelial nitric oxide (NO) in vascular Aβ accumulation. eNOS+/- mice had significantly higher vascular levels of Aβ40 (P < 0.05). Aβ42 was not detected. There was no difference in Aβ in brain tissue. Amyloid precursor protein and β-site APP cleavage enzyme 1 protein levels were unaltered, while levels of the α-secretase enzyme, a disintegrin and metalloproteinase 10, were significantly lower in eNOS + /- microvascular tissue (P < 0.05). Insulin degrading enzyme and low-density lipoprotein receptor-related protein 1 were significantly increased in eNOS+/- microvascular tissue, most likely an adaptive response to locally higher Aβ concentrations. Lastly, catalase and CuZn superoxide dismutase were significantly elevated in eNOS+/- microvascular tissue (P < 0.05). These data demonstrate decreased availability of endothelial NO leads to increased cerebrovascular concentration of Aβ along with compensatory mechanisms to protect the vasculature.
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Affiliation(s)
- Susan A Austin
- Departments of Anesthesiology and Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic College of Medicine, Rochester, MN, USA
| | - Zvonimir S Katusic
- Departments of Anesthesiology and Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic College of Medicine, Rochester, MN, USA
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Storck SE, Pietrzik CU. Endothelial LRP1 - A Potential Target for the Treatment of Alzheimer's Disease : Theme: Drug Discovery, Development and Delivery in Alzheimer's Disease Guest Editor: Davide Brambilla. Pharm Res 2017; 34:2637-2651. [PMID: 28948494 DOI: 10.1007/s11095-017-2267-3] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2017] [Accepted: 09/15/2017] [Indexed: 12/19/2022]
Abstract
The accumulation of the neurotoxin beta-amyloid (Aβ) is a major hallmark in Alzheimer's disease (AD). Aβ homeostasis in the brain is governed by its production and various clearance mechanisms. Both pathways are influenced by the ubiquitously expressed low-density lipoprotein receptor-related protein 1 (LRP1). In cerebral blood vessels, LRP1 is an important mediator for the rapid removal of Aβ from brain via transport across the blood-brain barrier (BBB). Here, we summarize recent findings on LRP1 function and discuss the targeting of LRP1 as a modulator for AD pathology and drug delivery into the brain.
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Affiliation(s)
- Steffen E Storck
- Molecular Neurodegeneration, Institute for Pathobiochemistry, University Medical Center of the Johannes Gutenberg-University, Duesbergweg 6, 55099, Mainz, Germany
| | - Claus U Pietrzik
- Molecular Neurodegeneration, Institute for Pathobiochemistry, University Medical Center of the Johannes Gutenberg-University, Duesbergweg 6, 55099, Mainz, Germany.
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Allen N, Robinson AC, Snowden J, Davidson YS, Mann DMA. Patterns of cerebral amyloid angiopathy define histopathological phenotypes in Alzheimer's disease. Neuropathol Appl Neurobiol 2014; 40:136-48. [PMID: 23808763 DOI: 10.1111/nan.12070] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2013] [Accepted: 06/11/2013] [Indexed: 11/26/2022]
Abstract
AIMS Pathological heterogeneity of Aβ deposition in senile plaques (SP) and cerebral amyloid angiopathy (CAA) in Alzheimer's disease (AD) has been long noted. The aim of this study was to classify cases of AD according to their pattern of Aβ deposition, and to seek factors which might predict, or predispose towards, this heterogeneity. METHODS The form, distribution and severity of Aβ deposition (as SP and/or CAA) was assessed semiquantitatively in immunostained sections of frontal, temporal and occipital cortex from 134 pathologically confirmed cases of AD. RESULTS Four patterns of Aβ deposition were defined. Type 1 describes cases predominantly with SP, with or without CAA within leptomeningeal vessels alone. Type 2 describes cases where, along with many SP, CAA is present in both leptomeningeal and deeper penetrating arteries. Type 3 describes cases where capillary CAA is present along with SP and arterial CAA. Type 4 describes a predominantly vascular phenotype, where Aβ deposition is much more prevalent in and around blood vessels, than as SP. As would be anticipated from the group definitions, there were significant differences in the distribution and degree of CAA across the phenotype groups, although Aβ deposition as SP did not vary. There were no significant differences between phenotype groups with regard to age of onset, age at death, disease duration and brain weight, or disease presentation. Women were over-represented in the type 1 phenotype and men in type 2. Genetically, type 3 (capillary subtype) cases were strongly associated with possession of the APOE ε4 allele. CONCLUSIONS This study offers an alternative method of pathologically classifying cases of AD. Further studies may derive additional genetic, environmental or clinical factors which associate with, or may be responsible for, these varying pathological presentations of AD.
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Affiliation(s)
- N Allen
- Clinical and Cognitive Sciences Research Group, Institute of Brain, Behaviour and Mental Health, Faculty of Medical and Human Sciences, University of Manchester, Salford Royal Hospital, Salford, UK
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Mitochondrial oxygen consumption deficits in skeletal muscle isolated from an Alzheimer's disease-relevant murine model. BMC Neurosci 2014; 15:24. [PMID: 24524276 PMCID: PMC3930757 DOI: 10.1186/1471-2202-15-24] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2014] [Accepted: 02/04/2014] [Indexed: 11/10/2022] Open
Abstract
Background Age is considered a primary risk factor for neurodegenerative diseases including Alzheimer’s disease (AD). It is also now well understood that mitochondrial function declines with age. Mitochondrial deficits have been previously assessed in brain from both human autopsy tissue and disease-relevant transgenic mice. Recently it has been recognized that abnormalities of muscle may be an intrinsic aspect of AD and might contribute to the pathophysiology. However, deficits in mitochondrial function have yet to be clearly assessed in tissues outside the central nervous system (CNS). In the present study, we utilized a well-characterized AD-relevant transgenic mouse strain to assess mitochondrial respiratory deficits in both brain and muscle. In addition to mitochondrial function, we assessed levels of transgene-derived amyloid precursor protein (APP) in homogenates isolated from brain and muscle of these AD-relevant animals. Results We now demonstrate that skeletal muscles isolated from these animals have differential levels of mutant full-length APP depending on muscle type. Additionally, isolated muscle fibers from young transgenic mice (3 months) have significantly decreased maximal mitochondrial oxygen consumption capacity compared to non-transgenic, age-matched mice, with similar deficits to those previously described in brain. Conclusions This is the first study to directly examine mitochondrial function in skeletal muscle from an AD-relevant transgenic murine model. As with brain, these deficits in muscle are an early event, occurring prior to appearance of amyloid plaques.
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Carare RO, Hawkes CA, Jeffrey M, Kalaria RN, Weller RO. Review: Cerebral amyloid angiopathy, prion angiopathy, CADASIL and the spectrum of protein elimination failure angiopathies (PEFA) in neurodegenerative disease with a focus on therapy. Neuropathol Appl Neurobiol 2013; 39:593-611. [DOI: 10.1111/nan.12042] [Citation(s) in RCA: 159] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2013] [Accepted: 03/07/2013] [Indexed: 01/03/2023]
Affiliation(s)
- R. O. Carare
- Clinical Neurosciences and Experimental Sciences; Faculty of Medicine; University of Southampton; Southampton; UK
| | - C. A. Hawkes
- Clinical Neurosciences and Experimental Sciences; Faculty of Medicine; University of Southampton; Southampton; UK
| | - M. Jeffrey
- Animal Health and Veterinary Laboratories Agency (AHVLA); Bush Loan Penicuik; Edinburgh; UK
| | - R. N. Kalaria
- Centre for Brain Ageing & Vitality; Institute for Ageing and Health; Newcastle University; Newcastle Upon Tyne; UK
| | - R. O. Weller
- Clinical Neurosciences and Experimental Sciences; Faculty of Medicine; University of Southampton; Southampton; UK
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11
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Shechter R, Schwartz M. Harnessing monocyte-derived macrophages to control central nervous system pathologies: no longer ‘if’ but ‘how’. J Pathol 2012; 229:332-46. [DOI: 10.1002/path.4106] [Citation(s) in RCA: 161] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2012] [Revised: 09/09/2012] [Accepted: 09/11/2012] [Indexed: 12/18/2022]
Affiliation(s)
- Ravid Shechter
- Department of Neurobiology; Weizmann Institute of Science; 76100 Rehovot Israel
| | - Michal Schwartz
- Department of Neurobiology; Weizmann Institute of Science; 76100 Rehovot Israel
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12
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Bulbarelli A, Lonati E, Brambilla A, Orlando A, Cazzaniga E, Piazza F, Ferrarese C, Masserini M, Sancini G. Aβ42 production in brain capillary endothelial cells after oxygen and glucose deprivation. Mol Cell Neurosci 2012; 49:415-22. [DOI: 10.1016/j.mcn.2012.01.007] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2011] [Revised: 12/06/2011] [Accepted: 01/25/2012] [Indexed: 12/30/2022] Open
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Yamada M, Naiki H. Cerebral Amyloid Angiopathy. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2012; 107:41-78. [DOI: 10.1016/b978-0-12-385883-2.00006-0] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
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Genetic animal models of cerebral vasculopathies. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2012; 105:25-55. [PMID: 22137428 DOI: 10.1016/b978-0-12-394596-9.00002-0] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Cerebral amyloid angiopathy (CAA) and cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) are genetic cerebrovasculopathies associated with neurodegeneration and vascular cognitive impairment. Linked to autosomal dominant mutations in diverse genes that encode cell-surface receptors (i.e., amyloid precursor protein in CAA and NOTCH3 in CADASIL), both diseases are associated with accumulation of abnormal material around cerebral vessels, such as amyloid in CAA or granular osmiophilic material in CADASIL. Both CAA and CADASIL share clinical features of white matter degeneration and infarcts, and vascular dementia in the human adult; microbleeds occur in both CADASIL and CAA, but large intracerebral hemorrhages are more characteristic for the latter. While the mechanisms are poorly understood, wall thickening, luminal narrowing, and eventual loss of vascular smooth muscle cells are overlapping pathologies involving leptomeningeal, and pial or penetrating small arteries and arterioles in CAA and CADASIL. Dysregulation of cerebral blood flow and eventual hypoperfusion are believed to be the key pathophysiological steps in neurodegeneration and cognitive impairment. Although animal models expressing CAA or CADASIL mutations have partially reproduced the human pathology, there has been marked heterogeneity in the phenotypic spectrum, possibly due to genetic background differences among mouse models, and obvious species differences between mouse and man. Here, we provide an overview of animal models of CAA and CADASIL and the insight on molecular and physiological mechanisms of disease gained from these models.
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Distinct and non-redundant roles of microglia and myeloid subsets in mouse models of Alzheimer's disease. J Neurosci 2011; 31:11159-71. [PMID: 21813677 DOI: 10.1523/jneurosci.6209-10.2011] [Citation(s) in RCA: 266] [Impact Index Per Article: 20.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Mononuclear phagocytes are important modulators of Alzheimer's disease (AD), but the specific functions of resident microglia, bone marrow-derived mononuclear cells, and perivascular macrophages have not been resolved. To elucidate the spatiotemporal roles of mononuclear phagocytes during disease, we targeted myeloid cell subsets from different compartments and examined disease pathogenesis in three different mouse models of AD (APP(swe/PS1), APP(swe), and APP23 mice). We identified chemokine receptor 2 (CCR2)-expressing myeloid cells as the population that was preferentially recruited to β-amyloid (Aβ) deposits. Unexpectedly, AD brains with dysfunctional microglia and devoid of parenchymal bone marrow-derived phagocytes did not show overt changes in plaque pathology and Aβ load. In contrast, restriction of CCR2 deficiency to perivascular myeloid cells drastically impaired β-amyloid clearance and amplified vascular Aβ deposition, while parenchymal plaque deposition remained unaffected. Together, our data advocate selective functions of CCR2-expressing myeloid subsets, which could be targeted specifically to modify disease burden in AD.
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Attems J, Jellinger K, Thal DR, Van Nostrand W. Review: sporadic cerebral amyloid angiopathy. Neuropathol Appl Neurobiol 2011; 37:75-93. [PMID: 20946241 DOI: 10.1111/j.1365-2990.2010.01137.x] [Citation(s) in RCA: 242] [Impact Index Per Article: 18.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Cerebral amyloid angiopathy (CAA) may result from focal to widespread amyloid-β protein (Aβ) deposition within leptomeningeal and intracortical cerebral blood vessels. In addition, pericapillary Aβ refers to Aβ depositions in the glia limitans and adjacent neuropil, whereas in capillary CAA Aβ depositions are present in the capillary wall. CAA may cause lobar intracerebral haemorrhages and microbleeds. Hypoperfusion and reduced vascular autoregulation due to CAA might cause infarcts and white matter lesions. CAA thus causes vascular lesions that potentially lead to (vascular) dementia and may further contribute to dementia by impeding the clearance of solutes out of the brain and transport of nutrients across the blood brain barrier. Severe CAA is an independent risk factor for cognitive decline. The clinical diagnosis of CAA is based on the assessment of associated cerebrovascular lesions. In addition, perivascular spaces in the white matter and reduced concentrations of both Aβ(40) and Aβ(42) in cerebrospinal fluid may prove to be suggestive for CAA. Transgenic mouse models that overexpress human Aβ precursor protein show parenchymal Aβ and CAA, thus corroborating the current concept of CAA pathogenesis: neuronal Aβ enters the perivascular drainage pathway and may accumulate in vessel walls due to increased amounts and/or decreased clearance of Aβ, respectively. We suggest that pericapillary Aβ represents early impairment of the perivascular drainage pathway while capillary CAA is associated with decreased transendothelial clearance of Aβ. CAA plays an important role in the multimorbid condition of the ageing brain but its contribution to neurodegeneration remains to be elucidated.
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Affiliation(s)
- J Attems
- Institute for Ageing and Health, Newcastle University, Newcastle upon Tyne, UK.
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Abstract
The only recognized genetic determinant of the common forms of Alzheimer's disease (AD) is the epsilon 4 allele of the apolipoprotein E gene (APOE). To identify new candidate genes, we recently performed transcriptomic analysis of 2741 genes in chromosomal regions of interest using brain tissue of AD cases and controls. From 82 differentially expressed genes, 1156 polymorphisms were genotyped in two independent discovery subsamples (n=945). Seventeen genes exhibited at least one polymorphism associated with AD risk, and following correction for multiple testing, we retained the interleukin (IL)-33 gene. We first confirmed that the IL-33 expression was decreased in the brain of AD cases compared with that of controls. Further genetic analysis led us to select three polymorphisms within this gene, which we analyzed in three independent case-control studies. These polymorphisms and a resulting protective haplotype were systematically associated with AD risk in non-APOE epsilon 4 carriers. Using a large prospective study, these associations were also detected when analyzing the prevalent and incident AD cases together or the incident AD cases alone. These polymorphisms were also associated with less cerebral amyloid angiopathy (CAA) in the brain of non-APOE epsilon 4 AD cases. Immunohistochemistry experiments finally indicated that the IL-33 expression was consistently restricted to vascular capillaries in the brain. Moreover, IL-33 overexpression in cellular models led to a specific decrease in secretion of the A beta(40) peptides, the main CAA component. In conclusion, our data suggest that genetic variants in IL-33 gene may be associated with a decrease in AD risk potentially in modulating CAA formation.
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18
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Maes OC, Schipper HM, Chertkow HM, Wang E. Methodology for discovery of Alzheimer's disease blood-based biomarkers. J Gerontol A Biol Sci Med Sci 2009; 64:636-45. [PMID: 19366883 DOI: 10.1093/gerona/glp045] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Alzheimer's disease (AD) is a degenerative brain disorder. The disease also affects peripheral tissue such as peripheral blood mononuclear cells (PBMCs). Delineating biochemical alterations in AD blood constituents may possibly allow the identification of accessible footprints that reflect degenerative processes within the central nervous system. Here, we describe an integrated methodology for the generation of a blood-based molecular bio-repository, including the collection of clinical and demographic data for downstream stringent sample selection and stratification for the study of molecular signatures in AD. We report the simultaneous extraction of high quality and yield of DNA, RNA, and protein from PBMCs of individuals with sporadic AD, mild cognitive impairment, and normal elderly controls. We describe experimental designs and present examples for the discovery of underlying etiopathogenetic networks in sporadic AD. We suggest that PBMC-associated biomarkers may provide insights into the pathogenesis of AD and be used to monitor disease diagnosis and progression.
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Affiliation(s)
- Olivier C Maes
- Centre for Neurotranslational Research, Bloomfield Centre for Research in Aging, Lady Davis Institute for Medical Research, Montréal, Québec, Canada
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Clifford PM, Siu G, Kosciuk M, Levin EC, Venkataraman V, D'Andrea MR, Nagele RG. Alpha7 nicotinic acetylcholine receptor expression by vascular smooth muscle cells facilitates the deposition of Abeta peptides and promotes cerebrovascular amyloid angiopathy. Brain Res 2008; 1234:158-71. [PMID: 18708033 DOI: 10.1016/j.brainres.2008.07.092] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2008] [Revised: 07/14/2008] [Accepted: 07/16/2008] [Indexed: 01/21/2023]
Abstract
Deposition of beta-amyloid (Abeta) peptides in the walls of brain blood vessels, cerebral amyloid angiopathy (CAA), is common in patients with Alzheimer's disease (AD). Previous studies have demonstrated Abeta peptide deposition among vascular smooth muscle cells (VSMCs), but the source of the Abeta and basis for its selective deposition in VSMCs are unknown. In the present study, we examined the deposition patterns of Abeta peptides, Abeta40 and Abeta42, within the cerebrovasculature of AD and control patients using single- and double-label immunohistochemistry. Abeta40 and Abeta42 were abundant in VSMCs, especially in leptomeningeal arteries and their initial cortical branches; in later-stage AD brains this pattern extended into the microvasculature. Abeta peptide deposition was linked to loss of VSMC viability. Perivascular leak clouds of Abeta-positive material were associated primarily with arterioles. By contrast, control brains possessed far fewer Abeta42- and Abeta40-immunopositive blood vessels, with perivascular leak clouds of Abeta-immunopositive material rarely observed. We also demonstrate that VSMCs in brain blood vessels express the alpha7 nicotinic acetylcholine receptor (alpha7nAChR), which has high binding affinity for Abeta peptides, especially Abeta42. These results suggest that the blood and blood-brain barrier permeability provide a major source of the Abeta peptides that gradually deposit in brain VSMCs, and the presence and abundance of the alpha7nAChR on VSMCs may facilitate the selective accumulation of Abeta peptides in these cells.
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Affiliation(s)
- Peter M Clifford
- University of Medicine and Dentistry of New Jersey/Graduate School of Biomedical Sciences, 2 Medical Center Drive, Stratford, NJ 08084, USA
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Coma M, Guix FX, Ill-Raga G, Uribesalgo I, Alameda F, Valverde MA, Muñoz FJ. Oxidative stress triggers the amyloidogenic pathway in human vascular smooth muscle cells. Neurobiol Aging 2008; 29:969-80. [PMID: 17306421 DOI: 10.1016/j.neurobiolaging.2007.01.009] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2006] [Revised: 12/01/2006] [Accepted: 01/13/2007] [Indexed: 10/23/2022]
Abstract
Cerebral amyloid angiopathy, associated to most cases of Alzheimer's disease (AD), is characterized by the deposition of amyloid ss-peptide (Ass) in brain vessels, although the origin of the vascular amyloid deposits is still controversial: neuronal versus vascular. In the present work, we demonstrate that primary cultures of human cerebral vascular smooth muscle cells (HC-VSMCs) have all the secretases involved in amyloid ss-protein precursor (APP) cleavage and produce Ass(1-40) and Ass(1-42). Oxidative stress, a key factor in the etiology and pathophysiology of AD, up-regulates ss-site APP cleaving enzyme 1 (BACE1) expression, as well as Ass(1-40) and Ass(1-42) secretion in HC-VSMCs. This process is mediated by c-Jun N-terminal Kinase and p38 MAPK signaling and appears restricted to BACE1 regulation as no changes in the other secretases were observed. In conclusion, oxidative stress-mediated up-regulation of the amyloidogenic pathway in human cerebral vascular smooth muscle cells may contribute to the overall cerebrovascular amyloid angiopathy observed in AD patients.
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Affiliation(s)
- Mireia Coma
- Laboratory of Molecular Physiology and Channelopathies, Universitat Pompeu Fabra, Parc de Recerca Biomèdica de Barcelona, Barcelona, Spain
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21
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Dynamics of the microglial/amyloid interaction indicate a role in plaque maintenance. J Neurosci 2008; 28:4283-92. [PMID: 18417708 DOI: 10.1523/jneurosci.4814-07.2008] [Citation(s) in RCA: 354] [Impact Index Per Article: 22.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Microglial cells aggregate around amyloid plaques in Alzheimer's disease, but, despite their therapeutic potential, various aspects of their reactive kinetics and role in plaque pathogenesis remain hypothetical. Through use of in vivo imaging and quantitative morphological measures in transgenic mice, we demonstrate that local resident microglia rapidly react to plaque formation by extending processes and subsequently migrating toward plaques, in which individual transformed microglia somata remain spatially stable for weeks. The number of plaque-associated microglia increased at a rate of almost three per plaque per month, independent of plaque volume. Larger plaques were surrounded by larger microglia, and a subset of plaques changed in size over time, with an increase or decrease related to the volume of associated microglia. Far from adopting a more static role, plaque-associated microglia retained rapid process and membrane movement at the plaque/glia interface. Microglia internalized systemically injected amyloid-binding dye at a much higher rate in the vicinity of plaques. These results indicate a role for microglia in plaque maintenance and provide a model with multiple targets for therapeutic intervention.
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Carare RO, Bernardes-Silva M, Newman TA, Page AM, Nicoll JAR, Perry VH, Weller RO. Solutes, but not cells, drain from the brain parenchyma along basement membranes of capillaries and arteries: significance for cerebral amyloid angiopathy and neuroimmunology. Neuropathol Appl Neurobiol 2008; 34:131-44. [PMID: 18208483 DOI: 10.1111/j.1365-2990.2007.00926.x] [Citation(s) in RCA: 435] [Impact Index Per Article: 27.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
UNLABELLED Elimination of interstitial fluid and solutes plays a role in homeostasis in the brain, but the pathways are unclear. Previous work suggests that interstitial fluid drains along the walls of arteries. AIMS to define the pathways within the walls of capillaries and arteries for drainage of fluid and solutes out of the brain. METHODS Fluorescent soluble tracers, dextran (3 kDa) and ovalbumin (40 kDa), and particulate fluospheres (0.02 microm and 1.0 microm in diameter) were injected into the corpus striatum of mice. Brains were examined from 5 min to 7 days by immunocytochemistry and confocal microscopy. RESULTS soluble tracers initially spread diffusely through brain parenchyma and then drain out of the brain along basement membranes of capillaries and arteries. Some tracer is takenf up by vascular smooth muscle cells and by perivascular macrophages. No perivascular drainage was observed when dextran was injected into mouse brains following cardiac arrest. Fluospheres expand perivascular spaces between vessel walls and surrounding brain, are ingested by perivascular macrophages but do not appear to leave the brain even following an inflammatory challenge with lipopolysaccharide or kainate. CONCLUSIONS capillary and artery basement membranes act as 'lymphatics of the brain' for drainage of fluid and solutes; such drainage appears to require continued cardiac output as it ceases following cardiac arrest. This drainage pathway does not permit migration of cells from brain parenchyma to the periphery. Amyloid-beta is deposited in basement membrane drainage pathways in cerebral amyloid angiopathy, and may impede elimination of amyloid-beta and interstitial fluid from the brain in Alzheimer's disease. Soluble antigens, but not cells, drain from the brain by perivascular pathways. This atypical pattern of drainage may contribute to partial immune privilege of the brain and play a role in neuroimmunological diseases such as multiple sclerosis.
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Affiliation(s)
- R O Carare
- Clinical Neurosciences, University of Southampton, UK
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23
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Weller RO, Subash M, Preston SD, Mazanti I, Carare RO. SYMPOSIUM: Clearance of Aβ from the Brain in Alzheimer's Disease: Perivascular Drainage of Amyloid-β Peptides from the Brain and Its Failure in Cerebral Amyloid Angiopathy and Alzheimer's Disease. Brain Pathol 2007; 18:253-66. [PMID: 18363936 DOI: 10.1111/j.1750-3639.2008.00133.x] [Citation(s) in RCA: 472] [Impact Index Per Article: 27.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Affiliation(s)
- Roy O Weller
- Clinical Neurosciences, School of Medicine, University of Southampton, Southampton General Hospital, Southampton, UK.
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Attems J, Quass M, Jellinger KA, Lintner F. Topographical distribution of cerebral amyloid angiopathy and its effect on cognitive decline are influenced by Alzheimer disease pathology. J Neurol Sci 2007; 257:49-55. [PMID: 17306303 DOI: 10.1016/j.jns.2007.01.013] [Citation(s) in RCA: 83] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Cerebral amyloid angiopathy (CAA) is defined by beta-amyloid peptide (Abeta) depositions in cerebral vessels and is associated with Alzheimer disease (AD). It has been suggested that severe CAA is an independent risk factor for cognitive decline. 171 autopsy brains underwent standardized neuropathological assessment, the patients age ranged from 54 to 104 years (mean age: 83.9 years, +/-9.2, 59.6% female, 56.1% clinically demented). Using immunohistochemistry, the severity of Abeta depositions in vessels was assessed semiquantitatively in the frontal, frontobasal, hippocampal, and occipital region, respectively. CAA was present in 117 cases (68.4%), with the occipital region being affected significantly stronger than other regions. The overall incidence of CAA was significantly higher in cases with high grade neuritic AD pathology (ADP) compared to those with low grade or no ADP. The severity of CAA significantly increased with increasing ADP, with CAA in the occipital region increasing significantly stronger than that in other regions. The association of CAA and clinical dementia failed to remain statistically significant when adjusting for concomitant ADP. However, in cases devoid of any ADP CAA was significantly associated with the presence of clinical dementia. These results indicate a strong association of AD with CAA, but do not unequivocally support reports suggesting CAA to be an independent risk factor for cognitive decline, except for a subgroup of demented patients lacking any ADP.
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Affiliation(s)
- Johannes Attems
- Institute of Pathology, Otto Wagner Hospital, Baumgartner Hohe 1, A-1145, Vienna, Austria.
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25
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Auerbach ID, Vinters HV. Effects of anoxia and hypoxia on amyloid precursor protein processing in cerebral microvascular smooth muscle cells. J Neuropathol Exp Neurol 2006; 65:610-20. [PMID: 16783171 DOI: 10.1097/00005072-200606000-00009] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Cerebral amyloid angiopathy (CAA) is characterized by the degeneration of cerebral microvascular smooth muscle cells (MV-SMC) and the replacement of normal vessel wall components by beta-amyloid (Abeta) protein. Little is known regarding the mechanisms of SMC degeneration in CAA. The effects of anoxia on the metabolism of the amyloid precursor protein (APP) were studied to investigate the MV-SMC response to anoxic stress and its possible role in the pathogenesis of CAA. MV-SMC exposed to chronic anoxia (24-48 hours) showed a decrease in expression of the 2 putative alpha-secretase enzymes, mature TACE (TNFalpha-converting enzyme) and ADAM10 (a disintegrin and metalloprotease). A concomitant decrease in the alpha-secretase cleavage products sAPPalpha and C83 was observed. Investigation of mRNA expression showed an increase in TACE and a sharp decrease in ADAM10 at 24 hours. Exposing MV-SMC to hypoxia (1% O2) revealed a different pattern of expression with no significant change in TACE protein, but an increase in TACE mRNA occurring at a later time point (48 hours). There was no change in ADAM10 mRNA expression, but a reduction in mature ADAM10 with a parallel increase in immature ADAM10 protein. These results demonstrate a requirement for oxygen in the regulation of the alpha-secretase pathway during APP metabolism.
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Affiliation(s)
- Ilene D Auerbach
- Department of Pathology and Laboratory Medicine (Neuropathology), the Brain Research Institute, David Geffen School of Medicine at UCLA, Los Angeles, CA 90095, USA
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Attems J. Sporadic cerebral amyloid angiopathy: pathology, clinical implications, and possible pathomechanisms. Acta Neuropathol 2005; 110:345-59. [PMID: 16170565 DOI: 10.1007/s00401-005-1074-9] [Citation(s) in RCA: 147] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2005] [Revised: 07/25/2005] [Accepted: 07/25/2005] [Indexed: 10/25/2022]
Abstract
Cerebral amyloid angiopathy (CAA) was observed for the first time nearly 100 years ago and systematically described in 1938. It is a common finding in elderly individuals, defined by beta-amyloid peptide (Abeta) depositions in cerebral blood vessels, and associated with Alzheimer's disease (AD). A variety of genetic mutations cause hereditary forms of CAA; in this review, however, only the sporadic variant of CAA is considered. In CAA, Abeta depositions primarily occur in the abluminal portion of the tunica media, and with increasing severity all layers of the blood vessel wall are infiltrated and an additional spread of Abeta into the surrounding neuropil may be seen (i.e., dyshoric changes). CAA is most pronounced in the occipital lobe and its distribution is usually patchy. The relationship between CAA and AD is poorly understood; however, low positive correlations between the severity of both CAA and AD pathology have been observed. CAA is a frequent cause of (warfarin-associated) intracerebral hemorrhage, and the diagnosis of probable CAA-related hemorrhage can be made during life with high accuracy. Both APOE-epsilon4 and APOE-epsilon2 are risk factors for CAA, while only APOE-epsilon2 increases the risk for hemorrhage in CAA. Although the role of CAA as an independent risk factor for cognitive decline is unclear, severe CAA is likely to lower the threshold for clinically overt dementia in neurodegenerative diseases. As for the origin of Abeta in CAA, it may be both produced by smooth muscle cells (vessel wall) and derived from neurons in the course of perivascular drainage.
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Affiliation(s)
- Johannes Attems
- Pathologic Institute, Otto Wagner Hospital, Baumgartner Höhe 1, 1145, Vienna, Austria.
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Attems J, Jellinger KA, Lintner F. Alzheimer's disease pathology influences severity and topographical distribution of cerebral amyloid angiopathy. Acta Neuropathol 2005; 110:222-31. [PMID: 16133541 DOI: 10.1007/s00401-005-1064-y] [Citation(s) in RCA: 116] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2005] [Revised: 07/07/2005] [Accepted: 07/07/2005] [Indexed: 12/31/2022]
Abstract
Cerebral amyloid angiopathy (CAA) is defined by beta-amyloid peptide (Abeta) depositions in cerebral vessels and is associated with Alzheimer's disease (AD). The relationship between sporadic CAA and AD, and the origin of Abeta in CAA are poorly understood. The aim of our study was to investigate the relationship between CAA and AD. Autopsy brains (n=113, 61.1% female, 55.8% clinically demented, age range 54-102 years, mean +/- SE 83.5+/-0.93 years) underwent standardized neuropathological assessment. CAA was evaluated in frontal, frontobasal, hippocampal, and occipital regions. Using immunohistochemistry, the severity of Abeta deposition in vessels was assessed semiquantitatively for each region separately. Evaluation of APOE genotype in 53 cases using real-time PCR showed significant correlations with severe AD pathology and CAA. CAA was present in 77 cases (68.1%), with the occipital region being affected significantly more often and more severely than other regions (P<0.01). Of brains without AD pathology 23.5% revealed CAA, whereas 24% with AD pathology showed no CAA. In concordance with other studies, the severity of both AD pathology and CAA showed a low, but significant correlation. This correlation, however, was only caused by the significant increase of occipital CAA with increasing AD pathology (P<0.01), and was independent of APOE genotype. Our results suggest that progressing AD pathology not only increases the severity of CAA, but also shifts its topographical distribution towards the occipital cortex.
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Affiliation(s)
- Johannes Attems
- Pathological Institute, Otto Wagner Hospital, Baumgartner Höhe 1, 1140, Vienna, Austria
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