1
|
Pourahmad R, saleki K, Zare Gholinejad M, Aram C, Soltani Farsani A, Banazadeh M, Tafakhori A. Exploring the effect of gut microbiome on Alzheimer's disease. Biochem Biophys Rep 2024; 39:101776. [PMID: 39099604 PMCID: PMC11296257 DOI: 10.1016/j.bbrep.2024.101776] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2024] [Revised: 06/30/2024] [Accepted: 07/04/2024] [Indexed: 08/06/2024] Open
Abstract
Alzheimer's disease (AD) is the most widespread and irreversible form of dementia and accounts for more than half of dementia cases. The most significant risk factors for AD are aging-related exacerbations, degradation of anatomical pathways, environmental variables and mitochondrial dysfunction. Finding a decisive therapeutic solution is a major current issue. Nuanced interactions between major neuropathological mechanisms in AD in patients and microbiome have recently gained rising attention. The presence of bacterial amyloid in the gut triggers the immune system, resulting in increased immune feedbacks and endogenous neuronal amyloid within the CNS. Also, early clinical research revealed that changing the microbiome with beneficial bacteria or probiotics could affect brain function in AD. New approaches focus on the possible neuroprotective action of disease-modifying medications in AD. In the present review, we discuss the impact of the gut microbiota on the brain and review emerging research that suggests a disruption in the microbiota-brain axis can affect AD by mediating neuroinflammation. Such novel methods could help the development of novel therapeutics for AD.
Collapse
Affiliation(s)
- Ramtin Pourahmad
- School of Medicine, Tehran University of Medical Sciences, Tehran, Iran
- Network of Immunity in Infection, Malignancy and Autoimmunity (NIIMA), Universal Scientific Education and Research Network (USERN), Tehran, Iran
| | - Kiarash saleki
- Student Research Committee, Babol University of Medical Sciences, Babol, Iran
- USERN Office, Babol University of Medical Sciences, Babol, Iran
- Department of E-Learning in Medical Sciences, Faculty of Medical Education and Learning Technologies, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | | | - Cena Aram
- Department of Cell & Molecular Biology, Faculty of Biological Sciences, Kharazmi University, Tehran, Iran
| | | | - Mohammad Banazadeh
- Pharmaceutical Sciences and Cosmetic Products Research Center, Kerman University of Medical Sciences, Kerman, Iran
| | - Abbas Tafakhori
- Department of Neurology, School of Medicine, Imam Khomeini Hospital, Tehran University of Medical Sciences, Tehran, Iran
| |
Collapse
|
2
|
van den Berg E, Kersten I, Brinkmalm G, Johansson K, de Kort AM, Klijn CJ, Schreuder FH, Gobom J, Stoops E, Portelius E, Gkanatsiou E, Zetterberg H, Blennow K, Kuiperij HB, Verbeek MM. Profiling amyloid-β peptides as biomarkers for cerebral amyloid angiopathy. J Neurochem 2024; 168:1254-1264. [PMID: 38362804 PMCID: PMC11260253 DOI: 10.1111/jnc.16074] [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: 10/25/2023] [Revised: 01/08/2024] [Accepted: 01/24/2024] [Indexed: 02/17/2024]
Abstract
Brain amyloid-β (Aβ) deposits are key pathological hallmarks of both cerebral amyloid angiopathy (CAA) and Alzheimer's disease (AD). Microvascular deposits in CAA mainly consist of the Aβ40 peptide, whereas Aβ42 is the predominant variant in parenchymal plaques in AD. The relevance in pathogenesis and diagnostic accuracy of various other Aβ isoforms in CAA remain understudied. We aimed to investigate the biomarker potential of various Aβ isoforms in cerebrospinal fluid (CSF) to differentiate CAA from AD pathology. We included 25 patients with probable CAA, 50 subjects with a CSF profile indicative of AD pathology (AD-like), and 23 age- and sex-matched controls. CSF levels of Aβ1-34, Aβ1-37, Aβ1-38, Aβ1-39, Aβ1-40, and Aβ1-42 were quantified by liquid chromatography mass spectrometry. Lower CSF levels of all six Aβ peptides were observed in CAA patients compared with controls (p = 0.0005-0.03). Except for Aβ1-42 (p = 1.0), all peptides were decreased in CAA compared with AD-like subjects (p = 0.007-0.03). Besides Aβ1-42, none of the Aβ peptides were decreased in AD-like subjects compared with controls. All Aβ peptides combined differentiated CAA from AD-like subjects better (area under the curve [AUC] 0.84) than individual peptide levels (AUC 0.51-0.75). Without Aβ1-42 in the model (since decreased Aβ1-42 served as AD-like selection criterion), the AUC was 0.78 for distinguishing CAA from AD-like subjects. CAA patients and AD-like subjects showed distinct disease-specific CSF Aβ profiles. Peptides shorter than Aβ1-42 were decreased in CAA patients, but not AD-like subjects, which could suggest different pathological mechanisms between vascular and parenchymal Aβ accumulation. This study supports the potential use of this panel of CSF Aβ peptides to indicate presence of CAA pathology with high accuracy.
Collapse
Affiliation(s)
- Emma van den Berg
- Department of Neurology, Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Iris Kersten
- Department of Neurology, Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Gunnar Brinkmalm
- Institute of Neuroscience and Physiology, the Sahlgrenska Academy at the University of Gothenburg, Mölndal, Sweden
- Clinical Neurochemistry Laboratory, Sahlgrenska University Hospital, Mölndal, Sweden
| | - Kjell Johansson
- Clinical Neurochemistry Laboratory, Sahlgrenska University Hospital, Mölndal, Sweden
| | - Anna M. de Kort
- Department of Neurology, Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Catharina J.M. Klijn
- Department of Neurology, Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Floris H.B.M. Schreuder
- Department of Neurology, Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Johan Gobom
- Institute of Neuroscience and Physiology, the Sahlgrenska Academy at the University of Gothenburg, Mölndal, Sweden
- Clinical Neurochemistry Laboratory, Sahlgrenska University Hospital, Mölndal, Sweden
| | | | - Erik Portelius
- Clinical Neurochemistry Laboratory, Sahlgrenska University Hospital, Mölndal, Sweden
| | - Eleni Gkanatsiou
- Institute of Neuroscience and Physiology, the Sahlgrenska Academy at the University of Gothenburg, Mölndal, Sweden
- Clinical Neurochemistry Laboratory, Sahlgrenska University Hospital, Mölndal, Sweden
| | - Henrik Zetterberg
- Clinical Neurochemistry Laboratory, Sahlgrenska University Hospital, Mölndal, Sweden
- Department of Psychiatry and Neurochemistry, Institute of Neuroscience and Physiology, the Sahlgrenska Academy at the University of Gothenburg, Mölndal, Sweden
- UK Dementia Research Institute at UCL, London, United Kingdom
- Department of Neurodegenerative Disease, UCL Institute of Neurology, London, United Kingdom
- Hong Kong Center for Neurodegenerative Diseases, Clear Water Bay, Hong Kong, China
- Wisconsin Alzheimer’s Disease Research Center, University of Wisconsin School of Medicine and Public Health, University of Wisconsin-Madison, Madison, WI, USA
| | - Kaj Blennow
- Institute of Neuroscience and Physiology, the Sahlgrenska Academy at the University of Gothenburg, Mölndal, Sweden
- Clinical Neurochemistry Laboratory, Sahlgrenska University Hospital, Mölndal, Sweden
| | - H. Bea Kuiperij
- Department of Neurology, Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Marcel M. Verbeek
- Department of Neurology, Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center, Nijmegen, The Netherlands
- Department of Human Genetics, Radboud University Medical Center, Nijmegen, The Netherlands
| |
Collapse
|
3
|
Bohannon DG, Long D, Okhravi HR, Lee SC, De Jesus CL, Neubert TA, Rostagno AA, Ghiso JA, Kim WK. Functionally distinct pericyte subsets differently regulate amyloid-β deposition in patients with Alzheimer's disease. Brain Pathol 2024:e13282. [PMID: 38932696 DOI: 10.1111/bpa.13282] [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: 02/05/2024] [Accepted: 06/11/2024] [Indexed: 06/28/2024] Open
Abstract
Although the concept that the blood-brain barrier (BBB) plays an important role in the etiology and pathogenesis of Alzheimer's disease (AD) has become increasingly accepted, little is known yet about how it actually contributes. We and others have recently identified a novel functionally distinct subset of BBB pericytes (PCs). In the present study, we sought to determine whether these PC subsets differentially contribute to AD-associated pathologies by immunohistochemistry and amyloid beta (Aβ) peptidomics. We demonstrated that a disease-associated PC subset (PC2) expanded in AD patients compared to age-matched, cognitively unimpaired controls. Surprisingly, we found that this increase in the percentage of PC2 (%PC2) was correlated negatively with BBB breakdown in AD patients, unlike in natural aging or other reported disease conditions. The higher %PC2 in AD patients was also correlated with a lower Aβ42 plaque load and a lower Aβ42:Aβ40 ratio in the brain as determined by immunohistochemistry. Colocalization analysis of multicolor confocal immunofluorescence microscopy images suggests that AD patient with low %PC2 have higher BBB breakdown due to internalization of Aβ42 by the physiologically normal PC subset (PC1) and their concomitant cell death leading to more vessels without PCs and increased plaque load. On the contrary, it appears that PC2 can secrete cathepsin D to cleave and degrade Aβ built up outside of PC2 into more soluble forms, ultimately contributing to less BBB breakdown and reducing Aβ plaque load. Collectively our data shows functionally distinct mechanisms for PC1 and PC2 in high Aβ conditions, demonstrating the importance of correctly identifying these populations when investigating the contribution of neurovascular dysfunction to AD pathogenesis.
Collapse
Affiliation(s)
- Diana G Bohannon
- Department of Microbiology and Molecular Cell Biology, Eastern Virginia Medical School, Norfolk, Virginia, USA
| | - Danielle Long
- Department of Microbiology and Molecular Cell Biology, Eastern Virginia Medical School, Norfolk, Virginia, USA
| | - Hamid R Okhravi
- Glennan Center for Geriatrics and Gerontology, Eastern Virginia Medical School, Norfolk, Virginia, USA
- Integrated Neurodegenerative Disorders Center, Eastern Virginia Medical School, Norfolk, Virginia, USA
| | - Sunhee C Lee
- Regeneron Pharmaceuticals, Inc, Tarrytown, New York, USA
| | | | - Thomas A Neubert
- Department of Neuroscience and Physiology, New York University Grossman School of Medicine, New York, New York, USA
| | - Agueda A Rostagno
- Department of Pathology, New York University Grossman School of Medicine, New York, New York, USA
| | - Jorge A Ghiso
- Department of Pathology, New York University Grossman School of Medicine, New York, New York, USA
- Department of Psychiatry, New York University Grossman School of Medicine, New York, New York, USA
| | - Woong-Ki Kim
- Department of Microbiology and Molecular Cell Biology, Eastern Virginia Medical School, Norfolk, Virginia, USA
- Integrated Neurodegenerative Disorders Center, Eastern Virginia Medical School, Norfolk, Virginia, USA
- Division of Microbiology, Tulane National Primate Research Center, Covington, Louisiana, USA
- Department of Microbiology and Immunology, Tulane University School of Medicine, New Orleans, Louisiana, USA
| |
Collapse
|
4
|
Klafki HW, Wirths O, Jahn O, Morgado B, Esselmann H, Wiltfang J. Blood plasma biomarkers for Alzheimer's disease: Aβ1-42/1-40 vs. AβX-42/X-40. Clin Chem Lab Med 2024; 62:e56-e57. [PMID: 37775501 DOI: 10.1515/cclm-2023-0990] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2023] [Accepted: 09/21/2023] [Indexed: 10/01/2023]
Affiliation(s)
- Hans-Wolfgang Klafki
- Department of Psychiatry and Psychotherapy, University Medical Center, Goettingen, Georg-August-University, Goettingen, Germany
| | - Oliver Wirths
- Department of Psychiatry and Psychotherapy, University Medical Center, Goettingen, Georg-August-University, Goettingen, Germany
| | - Olaf Jahn
- Department of Psychiatry and Psychotherapy, University Medical Center, Goettingen, Georg-August-University, Goettingen, Germany
| | - Barbara Morgado
- Department of Psychiatry and Psychotherapy, University Medical Center, Goettingen, Georg-August-University, Goettingen, Germany
| | - Hermann Esselmann
- Department of Psychiatry and Psychotherapy, University Medical Center, Goettingen, Georg-August-University, Goettingen, Germany
| | - Jens Wiltfang
- Department of Psychiatry and Psychotherapy, University Medical Center, Goettingen, Georg-August-University, Goettingen, Germany
| |
Collapse
|
5
|
Loeffler DA. Approaches for Increasing Cerebral Efflux of Amyloid-β in Experimental Systems. J Alzheimers Dis 2024; 100:379-411. [PMID: 38875041 PMCID: PMC11307100 DOI: 10.3233/jad-240212] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/14/2024] [Indexed: 06/16/2024]
Abstract
Amyloid protein-β (Aβ) concentrations are increased in the brain in both early onset and late onset Alzheimer's disease (AD). In early onset AD, cerebral Aβ production is increased and its clearance is decreased, while increased Aβ burden in late onset AD is due to impaired clearance. Aβ has been the focus of AD therapeutics since development of the amyloid hypothesis, but efforts to slow AD progression by lowering brain Aβ failed until phase 3 trials with the monoclonal antibodies lecanemab and donanemab. In addition to promoting phagocytic clearance of Aβ, antibodies lower cerebral Aβ by efflux of Aβ-antibody complexes across the capillary endothelia, dissolving Aβ aggregates, and a "peripheral sink" mechanism. Although the blood-brain barrier is the main route by which soluble Aβ leaves the brain (facilitated by low-density lipoprotein receptor-related protein-1 and ATP-binding cassette sub-family B member 1), Aβ can also be removed via the blood-cerebrospinal fluid barrier, glymphatic drainage, and intramural periarterial drainage. This review discusses experimental approaches to increase cerebral Aβ efflux via these mechanisms, clinical applications of these approaches, and findings in clinical trials with these approaches in patients with AD or mild cognitive impairment. Based on negative findings in clinical trials with previous approaches targeting monomeric Aβ, increasing the cerebral efflux of soluble Aβ is unlikely to slow AD progression if used as monotherapy. But if used as an adjunct to treatment with lecanemab or donanemab, this approach might allow greater slowing of AD progression than treatment with either antibody alone.
Collapse
Affiliation(s)
- David A. Loeffler
- Department of Neurology, Beaumont Research Institute, Corewell Health, Royal Oak, MI, USA
| |
Collapse
|
6
|
Sakai K, Noguchi-Shinohara M, Tanaka H, Ikeda T, Hamaguchi T, Kakita A, Yamada M, Ono K. Cerebrospinal Fluid Biomarkers and Amyloid-β Elimination from the Brain in Cerebral Amyloid Angiopathy-Related Inflammation. J Alzheimers Dis 2023; 91:1173-1183. [PMID: 36565118 DOI: 10.3233/jad-220838] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
BACKGROUND Cerebrospinal fluid (CSF) biomarkers in patients with cerebral amyloid angiopathy-related inflammation (CAA-ri) have demonstrated inconsistent results. OBJECTIVE We investigated the relationship between CSF amyloid-β protein (Aβ) and vascular pathological findings to elucidate the mechanisms of Aβ elimination from the brain in CAA-ri. METHODS We examined Aβ40 and Aβ42 levels in CSF samples in 15 patients with CAA-ri and 15 patients with Alzheimer's disease and cerebral amyloid angiopathy (AD-CAA) using ELISA as a cross-sectional study. Furthermore, we pathologically examined Aβ40 and Aβ42 depositions on the leptomeningeal blood vessels (arteries, arterioles, and veins) using brain biopsy samples from six patients with acute CAA-ri and brain tissues of two autopsied patients with CAA-ri. RESULTS The median Aβ40 and Aβ42 levels in the CSF showed no significant difference between pre-treatment CAA-ri (Aβ40, 6837 pg/ml; Aβ42, 324 pg/ml) and AD-CAA (Aβ40, 7669 pg/ml, p = 0.345; Aβ42, 355 pg/ml, p = 0.760). Aβ40 and Aβ42 levels in patients with post-treatment CAA-ri (Aβ40, 1770 pg/ml, p = 0.056; Aβ42, 167 pg/ml, p = 0.006) were lower than those in patients with pre-treatment CAA-ri. Regarding Aβ40 and Aβ42 positive arteries, acute CAA-ri cases showed a higher frequency of partially Aβ-deposited blood vessels than postmortem CAA-ri cases (Aβ40, 20.8% versus 3.9%, p = 0.0714; Aβ42, 27.4% versus 2.0%, p = 0.0714, respectively). CONCLUSION Lower levels of CSF Aβ40 and Aβ42 could be biomarkers for the cessation of inflammation in CAA-ri reflecting the recovery of the intramural periarterial drainage pathway and vascular function.
Collapse
Affiliation(s)
- Kenji Sakai
- Department of Neurology, Joetsu General Hospital, Joetsu, Japan.,Department of Neurology, Kanazawa University Graduate School of Medical Sciences, Kanazawa, Japan
| | - Moeko Noguchi-Shinohara
- Department of Neurology, Kanazawa University Graduate School of Medical Sciences, Kanazawa, Japan.,Department of Preemptive Medicine for Dementia, Kanazawa University Graduate School of Medical Sciences, Kanazawa, Japan
| | - Hidetomo Tanaka
- Department of Pathology, Brain Research Institute, Niigata University, Niigata, Japan
| | - Tokuhei Ikeda
- Department of Neurology, Kanazawa University Graduate School of Medical Sciences, Kanazawa, Japan
| | - Tsuyoshi Hamaguchi
- Department of Neurology, Kanazawa University Graduate School of Medical Sciences, Kanazawa, Japan.,Department of Neurology, Kanazawa Medical University, Uchinada, Japan
| | - Akiyoshi Kakita
- Department of Pathology, Brain Research Institute, Niigata University, Niigata, Japan
| | - Masahito Yamada
- Department of Neurology, Kanazawa University Graduate School of Medical Sciences, Kanazawa, Japan.,Department of Internal Medicine, Kudanzaka Hospital, Tokyo, Japan
| | - Kenjiro Ono
- Department of Neurology, Kanazawa University Graduate School of Medical Sciences, Kanazawa, Japan
| |
Collapse
|
7
|
Is plasma amyloid-β 1–42/1–40 a better biomarker for Alzheimer’s disease than AβX–42/X–40? Fluids Barriers CNS 2022; 19:96. [DOI: 10.1186/s12987-022-00390-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2022] [Accepted: 10/20/2022] [Indexed: 12/04/2022] Open
Abstract
Abstract
Background
A reduced amyloid-β (Aβ)42/40 peptide ratio in blood plasma represents a peripheral biomarker of the cerebral amyloid pathology observed in Alzheimer’s disease brains. The magnitude of the measurable effect in plasma is smaller than in cerebrospinal fluid, presumably due to dilution by Aβ peptides originating from peripheral sources. We hypothesized that the observable effect in plasma can be accentuated to some extent by specifically measuring Aβ1–42 and Aβ1–40 instead of AβX–42 and AβX–40.
Methods
We assessed the plasma AβX–42/X–40 and Aβ1–42/1–40 ratios in an idealized clinical sample by semi-automated Aβ immunoprecipitation followed by closely related sandwich immunoassays. The amyloid-positive and amyloid-negative groups (dichotomized according to Aβ42/40 in cerebrospinal fluid) were compared regarding the median difference, mean difference, standardized effect size (Cohen’s d) and receiver operating characteristic curves. For statistical evaluation, we applied bootstrapping.
Results
The median Aβ1–42/1–40 ratio was 20.86% lower in amyloid-positive subjects than in the amyloid-negative group, while the median AβX–42/X–40 ratio was only 15.56% lower. The relative mean difference between amyloid-positive and amyloid-negative subjects was −18.34% for plasma Aβ1–42/1–40 compared to −15.50% for AβX–42/X–40. Cohen’s d was 1.73 for Aβ1–42/1–40 and 1.48 for plasma AβX–42/X–40. Unadjusted p-values < 0.05 were obtained after .632 bootstrapping for all three parameters. Receiver operating characteristic analysis indicated very similar areas under the curves for plasma Aβ1–42/1–40 and AβX–42/X–40.
Conclusions
Our findings support the hypothesis that the relatively small difference in the plasma Aβ42/40 ratio between subjects with and without evidence of brain amyloidosis can be accentuated by specifically measuring Aβ1–42/1–40 instead of AβX–42/X–40. A simplified theoretical model explaining this observation is presented.
Collapse
|
8
|
N-terminally truncated Aβ4-x proteoforms and their relevance for Alzheimer's pathophysiology. Transl Neurodegener 2022; 11:30. [PMID: 35641972 PMCID: PMC9158284 DOI: 10.1186/s40035-022-00303-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2021] [Accepted: 04/21/2022] [Indexed: 01/22/2023] Open
Abstract
Background The molecular heterogeneity of Alzheimer’s amyloid-β (Aβ) deposits extends well beyond the classic Aβ1-40/Aβ1-42 dichotomy, substantially expanded by multiple post-translational modifications that increase the proteome diversity. Numerous truncated fragments consistently populate the brain Aβ peptidome, and their homeostatic regulation and potential contribution to disease pathogenesis are largely unknown. Aβ4-x peptides have been reported as major components of plaque cores and the limited studies available indicate their relative abundance in Alzheimer’s disease (AD). Methods Immunohistochemistry was used to assess the topographic distribution of Aβ4-x species in well-characterized AD cases using custom-generated monoclonal antibody 18H6—specific for Aβ4-x species and blind for full-length Aβ1-40/Aβ1-42—in conjunction with thioflavin-S and antibodies recognizing Aβx-40 and Aβx-42 proteoforms. Circular dichroism, thioflavin-T binding, and electron microscopy evaluated the biophysical and aggregation/oligomerization properties of full-length and truncated synthetic homologues, whereas stereotaxic intracerebral injections of monomeric and oligomeric radiolabeled homologues in wild-type mice were used to evaluate their brain clearance characteristics. Results All types of amyloid deposits contained the probed Aβ epitopes, albeit expressed in different proportions. Aβ4-x species showed preferential localization within thioflavin-S-positive cerebral amyloid angiopathy and cored plaques, strongly suggesting poor clearance characteristics and consistent with the reduced solubility and enhanced oligomerization of their synthetic homologues. In vivo clearance studies demonstrated a fast brain efflux of N-terminally truncated and full-length monomeric forms whereas their oligomeric counterparts—particularly of Aβ4-40 and Aβ4-42—consistently exhibited enhanced brain retention. Conclusions The persistence of aggregation-prone Aβ4-x proteoforms likely contributes to the process of amyloid formation, self-perpetuating the amyloidogenic loop and exacerbating amyloid-mediated pathogenic pathways.
Collapse
|
9
|
Sexton CE, Anstey KJ, Baldacci F, Barnum CJ, Barron AM, Blennow K, Brodaty H, Burnham S, Elahi FM, Götz J, Jeon YH, Koronyo-Hamaoui M, Landau SM, Lautenschlager NT, Laws SM, Lipnicki DM, Lu H, Masters CL, Moyle W, Nakamura A, Pasinetti GM, Rao N, Rowe C, Sachdev PS, Schofield PR, Sigurdsson EM, Smith K, Srikanth V, Szoeke C, Tansey MG, Whitmer R, Wilcock D, Wong TY, Bain LJ, Carrillo MC. Alzheimer's disease research progress in Australia: The Alzheimer's Association International Conference Satellite Symposium in Sydney. Alzheimers Dement 2022; 18:178-190. [PMID: 34058063 PMCID: PMC9396711 DOI: 10.1002/alz.12380] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2020] [Revised: 04/19/2021] [Accepted: 04/20/2021] [Indexed: 01/03/2023]
Abstract
The Alzheimer's Association International Conference held its sixth Satellite Symposium in Sydney, Australia in 2019, highlighting the leadership of Australian researchers in advancing the understanding of and treatment developments for Alzheimer's disease (AD) and other dementias. This leadership includes the Australian Imaging, Biomarker, and Lifestyle Flagship Study of Ageing (AIBL), which has fueled the identification and development of many biomarkers and novel therapeutics. Two multimodal lifestyle intervention studies have been launched in Australia; and Australian researchers have played leadership roles in other global studies in diverse populations. Australian researchers have also played an instrumental role in efforts to understand mechanisms underlying vascular contributions to cognitive impairment and dementia; and through the Women's Healthy Aging Project have elucidated hormonal and other factors that contribute to the increased risk of AD in women. Alleviating the behavioral and psychological symptoms of dementia has also been a strong research and clinical focus in Australia.
Collapse
Affiliation(s)
| | - Kaarin J. Anstey
- University of New South Wales and Neuroscience Research, Sydney, NSW, Australia
| | - Filippo Baldacci
- Unit of Neurology, Department of Clinical and Experimental Medicine, University of Pisa, Pisa, Italy
- GRC n° 21, Alzheimer Precision Medicine (APM), AP-HP, Pitié-Salpêtrière Hospital, Sorbonne University, Paris, France
| | | | - Anna M. Barron
- Lee Kong Chian School of Medicine, Nanyang Technological University Singapore, Singapore, Singapore
| | - Kaj Blennow
- Department of Psychiatry and Neurochemistry, Institute of Neuroscience and Physiology, The Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
- Clinical Neurochemistry Laboratory, Sahlgrenska University Hospital, Mölndal, Sweden
| | - Henry Brodaty
- Centre for Healthy Brain Ageing, University of New South Wales, Sydney, NSW, Australia
| | - Samantha Burnham
- CSIRO Health & Biosecurity, The Australian e-Health Research Centre, Parkville, VIC, Australia
| | - Fanny M. Elahi
- Memory and Aging Center, Weill Institute for NeurosciencesUniversity of California San Francisco, San Francisco, California, USA
| | - Jürgen Götz
- Clem Jones Centre for Ageing Dementia Research (CJCADR), Queensland Brain Institute (QBI), The University of Queensland, St Lucia Campus (Brisbane), Brisbane, QLD, Australia
| | - Yun-Hee Jeon
- The University of Sydney, Sydney, NSW, Australia
| | - Maya Koronyo-Hamaoui
- Departments of Neurosurgery and Biomedical Sciences, Maxine Dunitz Neurosurgical Institute, Cedars-Sinai Medical Center, Los Angeles, California, USA
| | - Susan M. Landau
- University of California Berkeley, Berkeley, California, USA
| | - Nicola T. Lautenschlager
- Academic Unit for Psychiatry of Old Age, Department of Psychiatry, The University of Melbourne, Melbourne, VIC, Australia
- North Western Mental Health, Royal Melbourne Hospital, Melbourne, Australia
| | - Simon M. Laws
- Collaborative Genomics and Translation Group, Edith Cowan University, Joondalup, WA, Australia
| | - Darren M. Lipnicki
- Centre for Healthy Brain Ageing, University of New South Wales, Sydney, NSW, Australia
| | - Hanzhang Lu
- Department of Radiology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Colin L. Masters
- The Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Melbourne, VIC, Australia
| | - Wendy Moyle
- Menzies Health Institute Queensland, Griffith University, Griffith, QLD, Australia
| | - Akinori Nakamura
- Department of Biomarker Research, National Center for Geriatrics and Gerontology, Obu, Japan
| | - Giulio Maria Pasinetti
- Department of Neurology, Icahn School of Medicine at Mount Sinai (ISSMS), New York, New York, USA
| | - Naren Rao
- Department of Psychiatry, National Institute of Mental Health and Neurosciences, Bengaluru, India
| | - Christopher Rowe
- The Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Melbourne, VIC, Australia
- Department of Molecular Imaging, Austin Health, Melbourne, VIC, Australia
| | - Perminder S. Sachdev
- Centre for Healthy Brain Ageing, University of New South Wales, Sydney, NSW, Australia
- Neuropsychiatric Institute, Prince of Wales Hospital, Sydney, NSW, Australia
| | - Peter R. Schofield
- Neuroscience Research Australia, Sydney and School of Medical Sciences, UNSW Sydney, Sydney, NSW, Australia
| | - Einar M. Sigurdsson
- Departments of Neuroscience and Physiology, and Psychiatry, Neuroscience Institute, New York University Grossman School of Medicine, New York, New York, USA
| | - Kate Smith
- Centre for Aboriginal Medical and Dental Health, University of Western Australia, Crawley, WA, Australia
| | - Velandai Srikanth
- Peninsula Clinical School, Central Clinical School, Monash University, Melbourne, VIC, Australia
| | | | - Malú G. Tansey
- Departments of Neuroscience and Neurology, Center for Translational Research in Neurodegenerative Disease, Normal Fixel Center for Neurological Diseases, University of Florida College of Medicine, Gainesville, Florida, USA
| | - Rachel Whitmer
- Department of Public Health Sciences, University of California, Davis, Davis, California, USA
| | - Donna Wilcock
- Sanders-Brown Center on Aging and Department of Physiology, University of Kentucky College of Medicine, Lexington, Kentucky, USA
| | - Tien Y. Wong
- Singapore Eye Research Institute, Singapore National Eye Center, Duke-NUS Medical School, National University of Singapore, Singapore, Singapore
| | - Lisa J. Bain
- Independent Science Writer, Elverson, Pennsylvania, USA
| | | |
Collapse
|
10
|
Jeong YM, Lee JG, Cho HJ, Lee WS, Jeong J, Lee JS. Differential Clearance of Aβ Species from the Brain by Brain Lymphatic Endothelial Cells in Zebrafish. Int J Mol Sci 2021; 22:11883. [PMID: 34769316 PMCID: PMC8584359 DOI: 10.3390/ijms222111883] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2021] [Revised: 10/28/2021] [Accepted: 10/29/2021] [Indexed: 02/01/2023] Open
Abstract
The failure of amyloid beta (Aβ) clearance is a major cause of Alzheimer's disease, and the brain lymphatic systems play a crucial role in clearing toxic proteins. Recently, brain lymphatic endothelial cells (BLECs), a non-lumenized lymphatic cell in the vertebrate brain, was identified, but Aβ clearance via this novel cell is not fully understood. We established an in vivo zebrafish model using fluorescently labeled Aβ42 to investigate the role of BLECs in Aβ clearance. We discovered the efficient clearance of monomeric Aβ42 (mAβ42) compared to oligomeric Aβ42 (oAβ42), which was illustrated by the selective uptake of mAβ42 by BLECs and peripheral transport. The genetic depletion, pharmacological inhibition via the blocking of the mannose receptor, or the laser ablation of BLECs resulted in the defective clearance of mAβ42. The treatment with an Aβ disaggregating agent facilitated the internalization of oAβ42 into BLECs and improved the peripheral transport. Our findings reveal a new role of BLECs in the differential clearance of mAβ42 from the brain and provide a novel therapeutic strategy based on promoting Aβ clearance.
Collapse
Affiliation(s)
- Yun-Mi Jeong
- Disease Target Structure Research Center, Korea Research Institute of Bioscience and Biotechnology, 125 Gwahak-ro, Yuseong-gu, Daejeon 34141, Korea
- Dementia DTC R&D Convergence Program, Korea Institute of Science and Technology, Hwarang-ro 14-gil 5, Seongbuk-gu, Seoul 02792, Korea
| | - Jae-Geun Lee
- Disease Target Structure Research Center, Korea Research Institute of Bioscience and Biotechnology, 125 Gwahak-ro, Yuseong-gu, Daejeon 34141, Korea
- Department of Functional Genomics, KRIBB School, University of Science and Technology, 217 Gajeong-ro, Yuseong-gu, Daejeon 34113, Korea
| | - Hyun-Ju Cho
- Disease Target Structure Research Center, Korea Research Institute of Bioscience and Biotechnology, 125 Gwahak-ro, Yuseong-gu, Daejeon 34141, Korea
| | - Wang Sik Lee
- Environmental Disease Research Center, Korea Research Institute of Bioscience and Biotechnology, 125 Gwahak-ro, Yuseong-gu, Daejeon 34141, Korea
| | - Jinyoung Jeong
- Environmental Disease Research Center, Korea Research Institute of Bioscience and Biotechnology, 125 Gwahak-ro, Yuseong-gu, Daejeon 34141, Korea
- Department of Biotechnology, KRIBB School, University of Science and Technology, 217 Gajeong-ro, Yuseong-gu, Daejeon 34113, Korea
| | - Jeong-Soo Lee
- Disease Target Structure Research Center, Korea Research Institute of Bioscience and Biotechnology, 125 Gwahak-ro, Yuseong-gu, Daejeon 34141, Korea
- Dementia DTC R&D Convergence Program, Korea Institute of Science and Technology, Hwarang-ro 14-gil 5, Seongbuk-gu, Seoul 02792, Korea
- Department of Functional Genomics, KRIBB School, University of Science and Technology, 217 Gajeong-ro, Yuseong-gu, Daejeon 34113, Korea
| |
Collapse
|
11
|
Yuan A, Nixon RA. Neurofilament Proteins as Biomarkers to Monitor Neurological Diseases and the Efficacy of Therapies. Front Neurosci 2021; 15:689938. [PMID: 34646114 PMCID: PMC8503617 DOI: 10.3389/fnins.2021.689938] [Citation(s) in RCA: 110] [Impact Index Per Article: 36.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2021] [Accepted: 09/02/2021] [Indexed: 01/01/2023] Open
Abstract
Biomarkers of neurodegeneration and neuronal injury have the potential to improve diagnostic accuracy, disease monitoring, prognosis, and measure treatment efficacy. Neurofilament proteins (NfPs) are well suited as biomarkers in these contexts because they are major neuron-specific components that maintain structural integrity and are sensitive to neurodegeneration and neuronal injury across a wide range of neurologic diseases. Low levels of NfPs are constantly released from neurons into the extracellular space and ultimately reach the cerebrospinal fluid (CSF) and blood under physiological conditions throughout normal brain development, maturation, and aging. NfP levels in CSF and blood rise above normal in response to neuronal injury and neurodegeneration independently of cause. NfPs in CSF measured by lumbar puncture are about 40-fold more concentrated than in blood in healthy individuals. New ultra-sensitive methods now allow minimally invasive measurement of these low levels of NfPs in serum or plasma to track disease onset and progression in neurological disorders or nervous system injury and assess responses to therapeutic interventions. Any of the five Nf subunits - neurofilament light chain (NfL), neurofilament medium chain (NfM), neurofilament heavy chain (NfH), alpha-internexin (INA) and peripherin (PRPH) may be altered in a given neuropathological condition. In familial and sporadic Alzheimer's disease (AD), plasma NfL levels may rise as early as 22 years before clinical onset in familial AD and 10 years before sporadic AD. The major determinants of elevated levels of NfPs and degradation fragments in CSF and blood are the magnitude of damaged or degenerating axons of fiber tracks, the affected axon caliber sizes and the rate of release of NfP and fragments at different stages of a given neurological disease or condition directly or indirectly affecting central nervous system (CNS) and/or peripheral nervous system (PNS). NfPs are rapidly emerging as transformative blood biomarkers in neurology providing novel insights into a wide range of neurological diseases and advancing clinical trials. Here we summarize the current understanding of intracellular NfP physiology, pathophysiology and extracellular kinetics of NfPs in biofluids and review the value and limitations of NfPs and degradation fragments as biomarkers of neurodegeneration and neuronal injury.
Collapse
Affiliation(s)
- Aidong Yuan
- Center for Dementia Research, Nathan Kline Institute, Orangeburg, NY, United States
- Department of Psychiatry, NYU Neuroscience Institute, New York, NY, United States
| | - Ralph A. Nixon
- Center for Dementia Research, Nathan Kline Institute, Orangeburg, NY, United States
- Department of Psychiatry, NYU Neuroscience Institute, New York, NY, United States
- Department of Cell Biology, New York University Grossman School of Medicine, (NYU), Neuroscience Institute, New York, NY, United States
| |
Collapse
|
12
|
Arévalo NB, Castillo-Godoy DP, Espinoza-Fuenzalida I, Rogers NK, Farias G, Delgado C, Henriquez M, Herrera L, Behrens MI, SanMartín CD. Association of Vitamin D Receptor Polymorphisms with Amyloid-β Transporters Expression and Risk of Mild Cognitive Impairment in a Chilean Cohort. J Alzheimers Dis 2021; 82:S283-S297. [DOI: 10.3233/jad-201031] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Background: Amyloid-β peptide (Aβ) deposition in Alzheimer’s disease (AD) is due to an imbalance in its production/clearance rate. Aβ is transported across the blood-brain barrier by LRP1 and P-gp as efflux transporters and RAGE as influx transporter. Vitamin D deficit and polymorphisms of the vitamin D receptor (VDR) gene are associated with high prevalence of mild cognitive impairment (MCI) and AD. Further, vitamin D promotes the expression of LRP1 and P-gp in AD-animal model brains. Objective: To associate VDR polymorphisms Apa I (rs7975232), Taq I (rs731236), and Fok I (rs2228570) with the risk of developing MCI in a Chilean population, and to evaluate the relationship of these polymorphisms to the expression of VDR and Aβ-transporters in peripheral blood mononuclear cells (PBMCs). Methods: VDR polymorphisms Apa I, Taq I, and Fok I were determined in 128 healthy controls (HC) and 66 MCI patients. mRNA levels of VDR and Aβ-transporters were evaluated in subgroups by qPCR. Results: Alleles A of Apa I and C of Taq I were associated with a lower risk of MCI. HC with the Apa I AA genotype had higher mRNA levels of P-gp and LRP1, while the expression of VDR and RAGE were higher in MCI patients and HC. For Fok I, the TC genotype was associated with lower expression levels of Aβ-transporters in both groups. Conclusion: We propose that the response to vitamin D treatment will depend on VDR polymorphisms, being more efficient in carriers of protective alleles of Apa I polymorphism.
Collapse
Affiliation(s)
- Nohela B. Arévalo
- Center for Integrative Biology, Faculty of Science, Universidad Mayor, Santiago, Chile
- Programa de Genética Humana, ICBM, Facultad de Medicina, Universidad de Chile, Santiago, Chile
| | | | | | - Nicole K. Rogers
- Departamento de Neurociencia, Facultad de Medicina, Universidad de Chile, Santiago, Chile
| | - Gonzalo Farias
- Departamento de Neurología y Neurocirugía, Hospital Clínico Universidad de Chile, Santiago, Chile
- Centro de Investigación Clínica Avanzada (CICA), Hospital Clínico Universidad de Chile, Santiago, Chile
| | - Carolina Delgado
- Departamento de Neurología y Neurocirugía, Hospital Clínico Universidad de Chile, Santiago, Chile
| | - Mauricio Henriquez
- Programa de Fisiología y Biofísica, Instituto de Ciencias Biomédicas (ICBM), Facultad de Medicina, Universidad de Chile, Santiago, Chile
- Red para el Estudio de Enfermedades Cardiopulmonares de Alta Letalidad (REECPAL), Universidad de Chile, Santiago, Chile
| | - Luisa Herrera
- Programa de Genética Humana, ICBM, Facultad de Medicina, Universidad de Chile, Santiago, Chile
| | - María Isabel Behrens
- Departamento de Neurociencia, Facultad de Medicina, Universidad de Chile, Santiago, Chile
- Departamento de Neurología y Neurocirugía, Hospital Clínico Universidad de Chile, Santiago, Chile
- Centro de Investigación Clínica Avanzada (CICA), Hospital Clínico Universidad de Chile, Santiago, Chile
- Departamento de Neurología y Psiquiatría, Clínica Alemana de Santiago, Santiago, Chile
| | - Carol D. SanMartín
- Center for Integrative Biology, Faculty of Science, Universidad Mayor, Santiago, Chile
- Departamento de Neurología y Neurocirugía, Hospital Clínico Universidad de Chile, Santiago, Chile
- Escuela de Tecnologia Médica, Facultad de Ciencias, Universidad Mayor, Santiago, Chile
- Escuela de Biotecnología, Facultad de Ciencias, Universidad Mayor, Santiago, Chile
| |
Collapse
|
13
|
Gafson AR, Barthélemy NR, Bomont P, Carare RO, Durham HD, Julien JP, Kuhle J, Leppert D, Nixon RA, Weller RO, Zetterberg H, Matthews PM. Neurofilaments: neurobiological foundations for biomarker applications. Brain 2020; 143:1975-1998. [PMID: 32408345 DOI: 10.1093/brain/awaa098] [Citation(s) in RCA: 155] [Impact Index Per Article: 38.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2019] [Revised: 12/20/2019] [Accepted: 01/20/2020] [Indexed: 12/11/2022] Open
Abstract
Interest in neurofilaments has risen sharply in recent years with recognition of their potential as biomarkers of brain injury or neurodegeneration in CSF and blood. This is in the context of a growing appreciation for the complexity of the neurobiology of neurofilaments, new recognition of specialized roles for neurofilaments in synapses and a developing understanding of mechanisms responsible for their turnover. Here we will review the neurobiology of neurofilament proteins, describing current understanding of their structure and function, including recently discovered evidence for their roles in synapses. We will explore emerging understanding of the mechanisms of neurofilament degradation and clearance and review new methods for future elucidation of the kinetics of their turnover in humans. Primary roles of neurofilaments in the pathogenesis of human diseases will be described. With this background, we then will review critically evidence supporting use of neurofilament concentration measures as biomarkers of neuronal injury or degeneration. Finally, we will reflect on major challenges for studies of the neurobiology of intermediate filaments with specific attention to identifying what needs to be learned for more precise use and confident interpretation of neurofilament measures as biomarkers of neurodegeneration.
Collapse
Affiliation(s)
- Arie R Gafson
- Department of Brain Sciences, Imperial College, London, UK
| | - Nicolas R Barthélemy
- Department of Neurology, Washington University School of Medicine, St Louis, MO, USA
| | - Pascale Bomont
- ATIP-Avenir team, INM, INSERM, Montpellier University, Montpellier, France
| | - Roxana O Carare
- Clinical Neurosciences, Faculty of Medicine, University of Southampton, Southampton General Hospital, Southampton, UK
| | - Heather D Durham
- Department of Neurology and Neurosurgery, Montreal Neurological Institute, McGill University, Montreal, Québec, Canada
| | - Jean-Pierre Julien
- Department of Psychiatry and Neuroscience, Laval University, Quebec, Canada.,CERVO Brain Research Center, 2601 Chemin de la Canardière, Québec, QC, G1J 2G3, Canada
| | - Jens Kuhle
- Neurologic Clinic and Policlinic, Departments of Medicine, Biomedicine and Clinical Research, University Hospital Basel, University of Basel, Basel, Switzerland
| | - David Leppert
- Neurologic Clinic and Policlinic, Departments of Medicine, Biomedicine and Clinical Research, University Hospital Basel, University of Basel, Basel, Switzerland
| | - Ralph A Nixon
- Center for Dementia Research, Nathan Kline Institute, Orangeburg, NY, 10962, USA.,Departments of Psychiatry, New York University School of Medicine, New York, NY, 10016, USA.,Neuroscience Institute, New York University School of Medicine, New York, NY, 10016, USA.,Department of Cell Biology, New York University School of Medicine, New York, NY, 10016, USA
| | - Roy O Weller
- Clinical Neurosciences, Faculty of Medicine, University of Southampton, Southampton General Hospital, Southampton, UK
| | - Henrik Zetterberg
- University College London Queen Square Institute of Neurology, London, UK.,UK Dementia Research Institute at University College London, London, UK.,Department of Psychiatry and Neurochemistry, Institute of Neuroscience and Physiology, the Sahlgrenska Academy at the University of Gothenburg, Mölndal, Sweden.,Clinical Neurochemistry Laboratory, Sahlgrenska University Hospital, Mölndal, Sweden
| | - Paul M Matthews
- Department of Brain Sciences, Imperial College, London, UK.,UK Dementia Research Institute at Imperial College, London
| |
Collapse
|
14
|
The Microbiota-Gut-Brain Axis and Alzheimer's Disease: Neuroinflammation Is to Blame? Nutrients 2020; 13:nu13010037. [PMID: 33374235 PMCID: PMC7824474 DOI: 10.3390/nu13010037] [Citation(s) in RCA: 124] [Impact Index Per Article: 31.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2020] [Revised: 12/20/2020] [Accepted: 12/22/2020] [Indexed: 02/06/2023] Open
Abstract
For years, it has been reported that Alzheimer’s disease (AD) is the most common cause of dementia. Various external and internal factors may contribute to the early onset of AD. This review highlights a contribution of the disturbances in the microbiota–gut–brain (MGB) axis to the development of AD. Alteration in the gut microbiota composition is determined by increase in the permeability of the gut barrier and immune cell activation, leading to impairment in the blood–brain barrier function that promotes neuroinflammation, neuronal loss, neural injury, and ultimately AD. Numerous studies have shown that the gut microbiota plays a crucial role in brain function and changes in the behavior of individuals and the formation of bacterial amyloids. Lipopolysaccharides and bacterial amyloids synthesized by the gut microbiota can trigger the immune cells residing in the brain and can activate the immune response leading to neuroinflammation. Growing experimental and clinical data indicate the prominent role of gut dysbiosis and microbiota–host interactions in AD. Modulation of the gut microbiota with antibiotics or probiotic supplementation may create new preventive and therapeutic options in AD. Accumulating evidences affirm that research on MGB involvement in AD is necessary for new treatment targets and therapies for AD.
Collapse
|
15
|
Parodi‐Rullán R, Ghiso J, Cabrera E, Rostagno A, Fossati S. Alzheimer's amyloid β heterogeneous species differentially affect brain endothelial cell viability, blood-brain barrier integrity, and angiogenesis. Aging Cell 2020; 19:e13258. [PMID: 33155752 PMCID: PMC7681048 DOI: 10.1111/acel.13258] [Citation(s) in RCA: 38] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2020] [Revised: 09/02/2020] [Accepted: 09/19/2020] [Indexed: 01/05/2023] Open
Abstract
Impaired clearance in the Alzheimer's Disease (AD) brain is key in the formation of Aβ parenchymal plaques and cerebrovascular deposits known as cerebral amyloid angiopathy (CAA), present in >80% of AD patients and ~50% of non-AD elderly subjects. Aβ deposits are highly heterogeneous, containing multiple fragments mostly derived from catabolism of Aβ40/Aβ42, which exhibit dissimilar aggregation properties. Remarkably, the role of these physiologically relevant Aβ species in cerebrovascular injury and their impact in vascular pathology is unknown. We sought to understand how heterogeneous Aβ species affect cerebral endothelial health and assess whether their diverse effects are associated with the peptides aggregation propensities. We analyzed cerebral microvascular endothelial cell (CMEC) viability, blood-brain barrier (BBB) permeability, and angiogenesis, all relevant aspects of brain microvascular dysfunction. We found that Aβ peptides and fragments exerted differential effects on cerebrovascular pathology. Peptides forming mostly oligomeric structures induced CMEC apoptosis, whereas fibrillar aggregates increased BBB permeability without apoptotic effects. Interestingly, all Aβ species tested inhibited angiogenesis in vitro. These data link the biological effects of the heterogeneous Aβ peptides to their primary structure and aggregation, strongly suggesting that the composition of amyloid deposits influences clinical aspects of the AD vascular pathology. As the presence of predominant oligomeric structures in proximity of the vessel walls may lead to CMEC death and induction of microhemorrhages, fibrillar amyloid is likely responsible for increased BBB permeability and associated neurovascular dysfunction. These results have the potential to unveil more specific therapeutic targets and clarify the multifactorial nature of AD.
Collapse
Affiliation(s)
- Rebecca Parodi‐Rullán
- Alzheimer's Center at Temple Lewis Katz School of Medicine Temple University Philadelphia PA USA
| | - Jorge Ghiso
- Department of Pathology New York University School of Medicine New York NY USA
- Department of Psychiatry New York University School of Medicine New York NY USA
| | - Erwin Cabrera
- Department of Pathology New York University School of Medicine New York NY USA
| | - Agueda Rostagno
- Department of Pathology New York University School of Medicine New York NY USA
| | - Silvia Fossati
- Alzheimer's Center at Temple Lewis Katz School of Medicine Temple University Philadelphia PA USA
| |
Collapse
|
16
|
Memory-Enhancing Effects of Origanum majorana Essential Oil in an Alzheimer's Amyloid beta1-42 Rat Model: A Molecular and Behavioral Study. Antioxidants (Basel) 2020; 9:antiox9100919. [PMID: 32993114 PMCID: PMC7600529 DOI: 10.3390/antiox9100919] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2020] [Revised: 09/23/2020] [Accepted: 09/24/2020] [Indexed: 12/18/2022] Open
Abstract
Origanum L. (Lamiaceae) is an important genus of medicinal and aromatic plants used in traditional medicine since ancient times as culinary herbs and remedies. The aim of the present study was to evaluate the chemical composition, as well as the biochemical and cellular activities of freshly prepared Origanum majorana L. essential oil (OmEO) in an Alzheimer’s disease (AD) amyloid beta1-42 (Aβ1-42) rat model. OmEO (1% and 3%) was inhaled for 21 consecutive days, while Aβ1-42 was administered intracerebroventricularly to induce AD-like symptoms. Our data demonstrate that OmEO increased antioxidant activity and enhanced brain-derived neurotrophic factor (BDNF) expression, which in concert contributed to the improvement of cognitive function of animals. Moreover, OmEO presented beneficial effects on memory performance in Y-maze and radial arm-maze tests in the Aβ1-42 rat AD model.
Collapse
|
17
|
Demonstrating a reduced capacity for removal of fluid from cerebral white matter and hypoxia in areas of white matter hyperintensity associated with age and dementia. Acta Neuropathol Commun 2020; 8:131. [PMID: 32771063 PMCID: PMC7414710 DOI: 10.1186/s40478-020-01009-1] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2020] [Accepted: 08/01/2020] [Indexed: 02/07/2023] Open
Abstract
White matter hyperintensities (WMH) occur in association with dementia but the aetiology is unclear. Here we test the hypothesis that there is a combination of impaired elimination of interstitial fluid from the white matter together with a degree of hypoxia in WMH. One of the mechanisms for the elimination of amyloid-β (Aβ) from the brain is along the basement membranes in the walls of capillaries and arteries (Intramural Peri-Arterial Drainage – IPAD). We compared the dynamics of IPAD in the grey matter of the hippocampus and in the white matter of the corpus callosum in 10 week old C57/B16 mice by injecting soluble Aβ as a tracer. The dynamics of IPAD in the white matter were significantly slower compared with the grey matter and this was associated with a lower density of capillaries in the white matter. Exposing cultures of smooth muscle cells to hypercapnia as a model of cerebral hypoperfusion resulted in a reduction in fibronectin and an increase in laminin in the extracellular matrix. Similar changes were detected in the white matter in human WMH suggesting that hypercapnia/hypoxia may play a role in WMH. Employing therapies to enhance both IPAD and blood flow in the white matter may reduce WMH in patients with dementia.
Collapse
|
18
|
Karkisaval AG, Rostagno A, Azimov R, Ban DK, Ghiso J, Kagan BL, Lal R. Ion channel formation by N-terminally truncated Aβ (4-42): relevance for the pathogenesis of Alzheimer's disease. NANOMEDICINE-NANOTECHNOLOGY BIOLOGY AND MEDICINE 2020; 29:102235. [PMID: 32531337 DOI: 10.1016/j.nano.2020.102235] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/14/2020] [Revised: 05/27/2020] [Accepted: 05/29/2020] [Indexed: 11/17/2022]
Abstract
Aβ deposition is a pathological hallmark of Alzheimer's disease (AD). Besides the full-length amyloid forming peptides (Aβ1-40 and Aβ1-42), biochemical analyses of brain deposits have identified a variety of N- and C-terminally truncated Aβ variants in sporadic and familial AD patients. However, their relevance for AD pathogenesis remains largely understudied. We demonstrate that Aβ4-42 exhibits a high tendency to form β-sheet structures leading to fast self-aggregation and formation of oligomeric assemblies. Atomic force microscopy and electrophysiological studies reveal that Aβ4-42 forms highly stable ion channels in lipid membranes. These channels that are blocked by monoclonal antibodies specifically recognizing the N-terminus of Aβ4-42. An Aβ variant with a double truncation at phenylalanine-4 and leucine 34, (Aβ4-34), exhibits unstable channel formation capability. Taken together the results presented herein highlight the potential benefit of C-terminal proteolytic cleavage and further support an important pathogenic role for N-truncated Aβ species in AD pathophysiology.
Collapse
Affiliation(s)
- Abhijith G Karkisaval
- Department of Mechanical and Aerospace Engineering, University of California San Diego, La Jolla, California, 92092, USA
| | - Agueda Rostagno
- Department of Pathology, New York University Grossman School of Medicine, 550 First Avenue, New York, NY, 10016, USA
| | - Rustam Azimov
- Department of Psychiatry, Geffen School of Medicine, University of California, Los Angeles, California 90095, USA; Semel Neuropsychiatric for Neuroscience & Human Behavior, University of California, Los Angeles, California 90095, United States
| | - Deependra K Ban
- Department of Mechanical and Aerospace Engineering, University of California San Diego, La Jolla, California, 92092, USA
| | - Jorge Ghiso
- Department of Pathology, New York University Grossman School of Medicine, 550 First Avenue, New York, NY, 10016, USA; Department of Psychiatry, New York University Grossman School of Medicine, 550 First Avenue, New York, NY, 10016, USA.
| | - Bruce L Kagan
- Department of Psychiatry, Geffen School of Medicine, University of California, Los Angeles, California 90095, USA; Semel Neuropsychiatric for Neuroscience & Human Behavior, University of California, Los Angeles, California 90095, United States.
| | - Ratnesh Lal
- Department of Mechanical and Aerospace Engineering, University of California San Diego, La Jolla, California, 92092, USA; Department of Bioengineering, University of California San Diego, La Jolla, California, 92092, USA; Materials Science and Engineering, University of California San Diego, La Jolla, California, 92092, USA.
| |
Collapse
|
19
|
Park YH, Shin SJ, Kim HS, Hong SB, Kim S, Nam Y, Kim JJ, Lim K, Kim JS, Kim JI, Jeon SG, Moon M. Omega-3 Fatty Acid-Type Docosahexaenoic Acid Protects against Aβ-Mediated Mitochondrial Deficits and Pathomechanisms in Alzheimer's Disease-Related Animal Model. Int J Mol Sci 2020; 21:ijms21113879. [PMID: 32486013 PMCID: PMC7312360 DOI: 10.3390/ijms21113879] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2020] [Revised: 05/27/2020] [Accepted: 05/27/2020] [Indexed: 12/18/2022] Open
Abstract
It has been reported that damage to the mitochondria affects the progression of Alzheimer's disease (AD), and that mitochondrial dysfunction is improved by omega-3. However, no animal or cell model studies have confirmed whether omega-3 inhibits AD pathology related to mitochondria deficits. In this study, we aimed to (1) identify mitigating effects of endogenous omega-3 on mitochondrial deficits and AD pathology induced by amyloid beta (Aβ) in fat-1 mice, a transgenic omega-3 polyunsaturated fatty acids (PUFAs)-producing animal; (2) identify if docosahexaenoic acid (DHA) improves mitochondrial deficits induced by Aβ in HT22 cells; and (3) verify improvement effects of DHA administration on mitochondrial deficits and AD pathology in B6SJL-Tg(APPSwFlLon,PSEN1*M146L*L286V)6799Vas/Mmjax (5XFAD), a transgenic Aβ-overexpressing model. We found that omega-3 PUFAs significantly improved Aβ-induced mitochondrial pathology in fat-1 mice. In addition, our in vitro and in vivo findings demonstrate that DHA attenuated AD-associated pathologies, such as mitochondrial impairment, Aβ accumulation, neuroinflammation, neuronal loss, and impairment of adult hippocampal neurogenesis.
Collapse
Affiliation(s)
- Yong Ho Park
- Department of Biochemistry, College of Medicine, Konyang University, 158, Gwanjeodong-ro, Seo-gu, Daejeon 35365, Korea; (Y.H.P.); (S.J.S.); (H.s.K.); (S.B.H.); (S.K.); (Y.N.)
| | - Soo Jung Shin
- Department of Biochemistry, College of Medicine, Konyang University, 158, Gwanjeodong-ro, Seo-gu, Daejeon 35365, Korea; (Y.H.P.); (S.J.S.); (H.s.K.); (S.B.H.); (S.K.); (Y.N.)
| | - Hyeon soo Kim
- Department of Biochemistry, College of Medicine, Konyang University, 158, Gwanjeodong-ro, Seo-gu, Daejeon 35365, Korea; (Y.H.P.); (S.J.S.); (H.s.K.); (S.B.H.); (S.K.); (Y.N.)
| | - Sang Bum Hong
- Department of Biochemistry, College of Medicine, Konyang University, 158, Gwanjeodong-ro, Seo-gu, Daejeon 35365, Korea; (Y.H.P.); (S.J.S.); (H.s.K.); (S.B.H.); (S.K.); (Y.N.)
| | - Sujin Kim
- Department of Biochemistry, College of Medicine, Konyang University, 158, Gwanjeodong-ro, Seo-gu, Daejeon 35365, Korea; (Y.H.P.); (S.J.S.); (H.s.K.); (S.B.H.); (S.K.); (Y.N.)
| | - Yunkwon Nam
- Department of Biochemistry, College of Medicine, Konyang University, 158, Gwanjeodong-ro, Seo-gu, Daejeon 35365, Korea; (Y.H.P.); (S.J.S.); (H.s.K.); (S.B.H.); (S.K.); (Y.N.)
| | - Jwa-Jin Kim
- Department of Nephrology, School of Medicine, Chungnam National University, Daejeon 35015, Korea;
| | - Kyu Lim
- Department of Biochemistry, School of Medicine, Chungnam National University, Daejeon 35015, Korea;
| | - Jong-Seok Kim
- Myunggok Medical Research Institute, College of Medicine, Konyang University, Daejeon 35365, Korea;
| | - Jin-il Kim
- Department of Nursing, College of Nursing, Jeju National University, Jeju-si 63243, Korea
- Correspondence: (J.-i.K.); (S.G.J.); (M.M.); Tel.: +82-64-754-3755 (J.-i.K.); +82-42-600-6450 (S.G.J.); +82-42-600-8694 (M.M.)
| | - Seong Gak Jeon
- Department of Biochemistry, College of Medicine, Konyang University, 158, Gwanjeodong-ro, Seo-gu, Daejeon 35365, Korea; (Y.H.P.); (S.J.S.); (H.s.K.); (S.B.H.); (S.K.); (Y.N.)
- Biopharmaceutical Chemistry Major, School of Applied Chemistry, Kookmin University, Seongbuk-gu, Seoul 02707, Korea
- Correspondence: (J.-i.K.); (S.G.J.); (M.M.); Tel.: +82-64-754-3755 (J.-i.K.); +82-42-600-6450 (S.G.J.); +82-42-600-8694 (M.M.)
| | - Minho Moon
- Department of Biochemistry, College of Medicine, Konyang University, 158, Gwanjeodong-ro, Seo-gu, Daejeon 35365, Korea; (Y.H.P.); (S.J.S.); (H.s.K.); (S.B.H.); (S.K.); (Y.N.)
- Correspondence: (J.-i.K.); (S.G.J.); (M.M.); Tel.: +82-64-754-3755 (J.-i.K.); +82-42-600-6450 (S.G.J.); +82-42-600-8694 (M.M.)
| |
Collapse
|
20
|
Durand D, Turati J, Rudi MJ, Ramírez D, Saba J, Caruso C, Carniglia L, von Bernhardi R, Lasaga M. Unraveling the β-amyloid clearance by astrocytes: Involvement of metabotropic glutamate receptor 3, sAPPα, and class-A scavenger receptor. Neurochem Int 2019; 131:104547. [DOI: 10.1016/j.neuint.2019.104547] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2019] [Revised: 09/13/2019] [Accepted: 09/16/2019] [Indexed: 12/24/2022]
|
21
|
Stefaniak E, Bal W. Cu II Binding Properties of N-Truncated Aβ Peptides: In Search of Biological Function. Inorg Chem 2019; 58:13561-13577. [PMID: 31304745 DOI: 10.1021/acs.inorgchem.9b01399] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
As life expectancy increases, the number of people affected by progressive and irreversible dementia, Alzheimer's Disease (AD), is predicted to grow. No drug designs seem to be working in humans, apparently because the origins of AD have not been identified. Invoking amyloid cascade, metal ions, and ROS production hypothesis of AD, herein we share our point of view on Cu(II) binding properties of Aβ4-x, the most prevalent N-truncated Aβ peptide, currently known as the main constituent of amyloid plaques. The capability of Aβ4-x to rapidly take over copper from previously tested Aβ1-x peptides and form highly stable complexes, redox unreactive and resistant to copper exchange reactions, prompted us to propose physiological roles for these peptides. We discuss the new findings on the reactivity of Cu(II)Aβ4-x with coexisting biomolecules in the context of synaptic cleft; we suggest that the role of Aβ4-x peptides is to quench Cu(II) toxicity in the brain and maintain neurotransmission.
Collapse
Affiliation(s)
- Ewelina Stefaniak
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences , Pawińskiego 5a , 02-106 Warsaw , Poland
| | - Wojciech Bal
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences , Pawińskiego 5a , 02-106 Warsaw , Poland
| |
Collapse
|
22
|
Gołaszewska A, Bik W, Motyl T, Orzechowski A. Bridging the Gap between Alzheimer's Disease and Alzheimer's-like Diseases in Animals. Int J Mol Sci 2019; 20:ijms20071664. [PMID: 30987146 PMCID: PMC6479525 DOI: 10.3390/ijms20071664] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2019] [Revised: 03/24/2019] [Accepted: 03/31/2019] [Indexed: 12/13/2022] Open
Abstract
The average life span steadily grows in humans and in animals kept as pets or left in sanctuaries making the issue of elderly-associated cognitive impairment a hot-spot for scientists. Alzheimer’s disease (AD) is the most prevalent cause of progressive mental deterioration in aging humans, and there is a growing body of evidence that similar disorders (Alzheimer’s-like diseases, ALD) are observed in animals, more than ever found in senescent individuals. This review reveals up to date knowledge in pathogenesis, hallmarks, diagnostic approaches and modalities in AD faced up with ALD related to different animal species. If found at necropsy, there are striking similarities between senile plaques (SP) and neurofibrillary tangles (NFT) in human and animal brains. Also, the set of clinical symptoms in ALD resembles that observed in AD. At molecular and microscopic levels, the human and animal brain histopathology in AD and ALD shows a great resemblance. AD is fatal, and the etiology is still unknown, although the myriad of efforts and techniques were employed in order to decipher the molecular mechanisms of disease onset and its progression. Nowadays, according to an increasing number of cases reported in animals, apparently, biochemistry of AD and ALD has a lot in common. Described observations point to the importance of extensive in vivo models and extensive pre-clinical studies on aging animals as a suitable model for AD disease.
Collapse
Affiliation(s)
- Anita Gołaszewska
- Department of Physiological Sciences, Faculty of Veterinary Medicine, Warsaw University of Life Sciences-SGGW, Nowoursynowska 159, 02-776 Warsaw, Poland.
- Department of Neuroendocrinology, Centre of Postgraduate Medical Education, Marymoncka 99/103, 01-813 Warsaw, Poland.
| | - Wojciech Bik
- Department of Neuroendocrinology, Centre of Postgraduate Medical Education, Marymoncka 99/103, 01-813 Warsaw, Poland.
| | - Tomasz Motyl
- Department of Physiological Sciences, Faculty of Veterinary Medicine, Warsaw University of Life Sciences-SGGW, Nowoursynowska 159, 02-776 Warsaw, Poland.
| | - Arkadiusz Orzechowski
- Department of Physiological Sciences, Faculty of Veterinary Medicine, Warsaw University of Life Sciences-SGGW, Nowoursynowska 159, 02-776 Warsaw, Poland.
| |
Collapse
|
23
|
Kowalski K, Mulak A. Brain-Gut-Microbiota Axis in Alzheimer's Disease. J Neurogastroenterol Motil 2019; 25:48-60. [PMID: 30646475 PMCID: PMC6326209 DOI: 10.5056/jnm18087] [Citation(s) in RCA: 445] [Impact Index Per Article: 89.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/18/2018] [Revised: 08/21/2018] [Accepted: 09/16/2018] [Indexed: 12/11/2022] Open
Abstract
Disturbances along the brain-gut-microbiota axis may significantly contribute to the pathogenesis of neurodegenerative disorders. Alzheimer's disease (AD) is the most frequent cause of dementia characterized by a progressive decline in cognitive function associated with the formation of amyloid beta (Aβ) plaques and neurofibrillary tangles. Alterations in the gut microbiota composition induce increased permeability of the gut barrier and immune activation leading to systemic inflammation, which in turn may impair the blood-brain barrier and promote neuroinflammation, neural injury, and ultimately neurodegeneration. Recently, Aβ has also been recognized as an antimicrobial peptide participating in the innate immune response. However, in the dysregulated state, Aβ may reveal harmful properties. Importantly, bacterial amyloids through molecular mimicry may elicit cross-seeding of misfolding and induce microglial priming. The Aβ seeding and propagation may occur at different levels of the brain-gut-microbiota axis. The potential mechanisms of amyloid spreading include neuron-to-neuron or distal neuron spreading, direct blood-brain barrier crossing or via other cells as astrocytes, fibroblasts, microglia, and immune system cells. A growing body of experimental and clinical data confirms a key role of gut dysbiosis and gut microbiota-host interactions in neurodegeneration. The convergence of gut-derived inflammatory response together with aging and poor diet in the elderly contribute to the pathogenesis of AD. Modification of the gut microbiota composition by food-based therapy or by probiotic supplementation may create new preventive and therapeutic options in AD.
Collapse
Affiliation(s)
- Karol Kowalski
- Department of Gastroenterology and Hepatology, Wroclaw Medical University, Poland
| | - Agata Mulak
- Department of Gastroenterology and Hepatology, Wroclaw Medical University, Poland
| |
Collapse
|
24
|
Abstract
Mechanisms for elimination of metabolites from ISF include metabolism, blood-brain barrier transport and non-selective, perivascular efflux, this last being assessed by measuring the clearance of markers like inulin. Clearance describes elimination. Clearance of a metabolite generated within the brain is determined as its elimination rate divided by its concentration in interstitial fluid (ISF). However, the more frequently measured parameter is the rate constant for elimination determined as elimination rate divided by amount present, which thus depends on both the elimination processes and the distribution of the metabolite in the brain. The relative importance of the various elimination mechanisms depends on the particular metabolite. Little is known about the effects of sleep on clearance via metabolism or blood-brain barrier transport, but studies with inulin in mice comparing perivascular effluxes during sleep and wakefulness reveal a 4.2-fold increase in clearance. Amongst the important brain metabolites considered, CO2 is eliminated so rapidly across the blood-brain barrier that clearance is blood flow limited and elimination quickly balances production. Glutamate is removed from ISF primarily by uptake into astrocytes and conversion to glutamine, but also by transport across the blood-brain barrier. Both lactate and amyloid-β are eliminated by metabolism, blood-brain barrier transport and perivascular efflux and both show decreased production, decreased ISF concentration and increased perivascular clearance during sleep. Taken altogether available data indicate that sleep increases perivascular and non-perivascular clearances for amyloid-β which reduces its concentration and may have long-term consequences for the formation of plaques and cerebral arterial deposits.
Collapse
Affiliation(s)
- Stephen B Hladky
- Department of Pharmacology, University of Cambridge, Cambridge, CB2 1PD, UK.
| | - Margery A Barrand
- Department of Pharmacology, University of Cambridge, Cambridge, CB2 1PD, UK
| |
Collapse
|
25
|
Bossak-Ahmad K, Mital M, Płonka D, Drew SC, Bal W. Oligopeptides Generated by Neprilysin Degradation of β-Amyloid Have the Highest Cu(II) Affinity in the Whole Aβ Family. Inorg Chem 2018; 58:932-943. [PMID: 30582328 DOI: 10.1021/acs.inorgchem.8b03051] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
The catabolism of β-amyloid (Aβ) is carried out by numerous endopeptidases including neprilysin, which hydrolyzes peptide bonds preceding positions 4, 10, and 12 to yield Aβ4-9 and a minor Aβ12- x species. Alternative processing of the amyloid precursor protein by β-secretase also generates the Aβ11- x species. All these peptides contain a Xxx-Yyy-His sequence, also known as an ATCUN or NTS motif, making them strong chelators of Cu(II) ions. We synthesized the corresponding peptides, Phe-Arg-His-Asp-Ser-Gly-OH (Aβ4-9), Glu-Val-His-His-Gln-Lys-am (Aβ11-16), Val-His-His-Gln-Lys-am (Aβ12-16), and pGlu-Val-His-His-Gln-Lys-am (pAβ11-16), and investigated their Cu(II) binding properties using potentiometry, and UV-vis, circular dichroism, and electron paramagnetic resonance spectroscopies. We found that the three peptides with unmodified N-termini formed square-planar Cu(II) complexes at pH 7.4 with analogous geometries but significantly varied Kd values of 6.6 fM (Aβ4-9), 9.5 fM (Aβ12-16), and 1.8 pM (Aβ11-16). Cyclization of the N-terminal Glu11 residue to the pyroglutamate species pAβ11-16 dramatically reduced the affinity (5.8 nM). The Cu(II) affinities of Aβ4-9 and Aβ12-16 are the highest among the Cu(II) complexes of Aβ peptides. Using fluorescence spectroscopy, we demonstrated that the Cu(II) exchange between the Phe-Arg-His and Val-His-His motifs is very slow, on the order of days. These results are discussed in terms of the relevance of Aβ4-9, a major Cu(II) binding Aβ fragment generated by neprilysin, as a possible Cu(II) carrier in the brain.
Collapse
Affiliation(s)
- Karolina Bossak-Ahmad
- Institute of Biochemistry and Biophysics , Polish Academy of Sciences , 02-106 Warsaw , Poland
| | - Mariusz Mital
- Institute of Biochemistry and Biophysics , Polish Academy of Sciences , 02-106 Warsaw , Poland
| | - Dawid Płonka
- Institute of Biochemistry and Biophysics , Polish Academy of Sciences , 02-106 Warsaw , Poland
| | - Simon C Drew
- Institute of Biochemistry and Biophysics , Polish Academy of Sciences , 02-106 Warsaw , Poland
| | - Wojciech Bal
- Institute of Biochemistry and Biophysics , Polish Academy of Sciences , 02-106 Warsaw , Poland
| |
Collapse
|
26
|
Hladky SB, Barrand MA. Elimination of substances from the brain parenchyma: efflux via perivascular pathways and via the blood-brain barrier. Fluids Barriers CNS 2018; 15:30. [PMID: 30340614 PMCID: PMC6194691 DOI: 10.1186/s12987-018-0113-6] [Citation(s) in RCA: 126] [Impact Index Per Article: 21.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2018] [Accepted: 08/30/2018] [Indexed: 02/06/2023] Open
Abstract
This review considers efflux of substances from brain parenchyma quantified as values of clearances (CL, stated in µL g-1 min-1). Total clearance of a substance is the sum of clearance values for all available routes including perivascular pathways and the blood-brain barrier. Perivascular efflux contributes to the clearance of all water-soluble substances. Substances leaving via the perivascular routes may enter cerebrospinal fluid (CSF) or lymph. These routes are also involved in entry to the parenchyma from CSF. However, evidence demonstrating net fluid flow inwards along arteries and then outwards along veins (the glymphatic hypothesis) is still lacking. CLperivascular, that via perivascular routes, has been measured by following the fate of exogenously applied labelled tracer amounts of sucrose, inulin or serum albumin, which are not metabolized or eliminated across the blood-brain barrier. With these substances values of total CL ≅ 1 have been measured. Substances that are eliminated at least partly by other routes, i.e. across the blood-brain barrier, have higher total CL values. Substances crossing the blood-brain barrier may do so by passive, non-specific means with CLblood-brain barrier values ranging from < 0.01 for inulin to > 1000 for water and CO2. CLblood-brain barrier values for many small solutes are predictable from their oil/water partition and molecular weight. Transporters specific for glucose, lactate and many polar substrates facilitate efflux across the blood-brain barrier producing CLblood-brain barrier values > 50. The principal route for movement of Na+ and Cl- ions across the blood-brain barrier is probably paracellular through tight junctions between the brain endothelial cells producing CLblood-brain barrier values ~ 1. There are large fluxes of amino acids into and out of the brain across the blood-brain barrier but only small net fluxes have been observed suggesting substantial reuse of essential amino acids and α-ketoacids within the brain. Amyloid-β efflux, which is measurably faster than efflux of inulin, is primarily across the blood-brain barrier. Amyloid-β also leaves the brain parenchyma via perivascular efflux and this may be important as the route by which amyloid-β reaches arterial walls resulting in cerebral amyloid angiopathy.
Collapse
Affiliation(s)
- Stephen B. Hladky
- Department of Pharmacology, University of Cambridge, Cambridge, CB2 1PD UK
| | - Margery A. Barrand
- Department of Pharmacology, University of Cambridge, Cambridge, CB2 1PD UK
| |
Collapse
|
27
|
Scavenger Receptor-A deficiency impairs immune response of microglia and astrocytes potentiating Alzheimer's disease pathophysiology. Brain Behav Immun 2018; 69:336-350. [PMID: 29246456 DOI: 10.1016/j.bbi.2017.12.007] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/09/2017] [Revised: 12/04/2017] [Accepted: 12/11/2017] [Indexed: 12/25/2022] Open
Abstract
Late onset Alzheimer disease's (LOAD) main risk factor is aging. Although it is not well known which age-related factors are involved in its development, evidence points out to the involvement of an impaired amyloid-β (Aβ) clearance in the aged brain among possible causes. Glial cells are the main scavengers of the brain, where Scavenger Receptor class A (SR-A) emerges as a relevant player in AD because of its participation in Aβ uptake and in the modulation of glial cell inflammatory response. Here, we show that SR-A expression is reduced in the hippocampus of aged animals and APP/PS1 mice. Given that Aβ deposition increases in the aging brain, we generated a triple transgenic mouse, which accumulates Aβ and is knockout for SR-A (APP/PS1/SR-A-/-) to evaluate Aβ accumulation and the inflammatory outcome of SR-A depletion in the aged brain. The lifespan of APP/PS1/SR-A-/- mice was greatly reduced, accompanied by a 3-fold increase in plasmatic pro-inflammatory cytokines, and reduced performance in a working memory behavioral assessment. Microglia and astrocytes lacking SR-A displayed impaired oxidative response and nitric oxide production, produced up to 7-fold more pro-inflammatory cytokines and showed a 12-fold reduction in anti-inflammatory cytokines release, with conspicuous changes in lipopolysaccharide-induced glial activation. Isolated microglia from young and adult mice lacking SR-A showed a 50% reduction in phagocytic activity. Our results indicate that reduced expression of SR-A can deregulate glial inflammatory response and potentiate Aβ accumulation, two mechanisms that could contribute to AD progression.
Collapse
|
28
|
Zandl-Lang M, Fanaee-Danesh E, Sun Y, Albrecher NM, Gali CC, Čančar I, Kober A, Tam-Amersdorfer C, Stracke A, Storck SM, Saeed A, Stefulj J, Pietrzik CU, Wilson MR, Björkhem I, Panzenboeck U. Regulatory effects of simvastatin and apoJ on APP processing and amyloid-β clearance in blood-brain barrier endothelial cells. Biochim Biophys Acta Mol Cell Biol Lipids 2018; 1863:40-60. [DOI: 10.1016/j.bbalip.2017.09.008] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2017] [Revised: 08/31/2017] [Accepted: 09/18/2017] [Indexed: 10/18/2022]
|
29
|
Abstract
Amyloid β (Aβ) is the major constituent of the brain deposits found in parenchymal plaques and cerebral blood vessels of patients with Alzheimer's disease (AD). Besides classic full-length peptides, biochemical analyses of brain deposits have revealed high degree of Aβ heterogeneity likely resulting from the action of multiple proteolytic enzymes. This chapter describes a sequential extraction protocol allowing the differential fractionation of soluble and deposited Aβ species taking advantage of their differential solubility properties. Soluble Aβ is extracted by water-based buffers like phosphate-buffered saline-PBS-whereas pre-fibrillar and fibrillar deposits, usually poorly soluble in PBS, are extractable in detergent containing solutions or more stringent conditions as formic acid. The extraction procedure is followed by the biochemical identification of the extracted Aβ species using Western blot and a targeted proteomic analysis which combines immunoprecipitation with MALDI-ToF mass spectrometry. This approach revealed the presence of numerous C- and N-terminal truncated Aβ species in addition to Aβ1-40/42. Notably, the more soluble C-terminal cleaved fragments constitute a main part of PBS homogenates. On the contrary, N-terminal truncated species typically require more stringent conditions for the extraction in agreement with their lower solubility and enhanced aggregability. Detailed assessment of the molecular diversity of Aβ species composing interstitial fluid and amyloid deposits at different disease stages, as well as the evaluation of the truncation profile during various pharmacologic approaches will provide a comprehensive understanding of the still undefined contribution of Aβ truncations to AD pathogenesis and their potential as novel therapeutic targets.
Collapse
Affiliation(s)
- Agueda Rostagno
- Department of Pathology, New York University School of Medicine, New York, NY, USA
| | - Thomas A Neubert
- Department of Biochemistry and Molecular Pharmacology, New York University School of Medicine, New York, NY, USA
- Kimmel Center for Biology and Medicine at the Skirball Institute, New York University School of Medicine, New York, NY, USA
| | - Jorge Ghiso
- Department of Pathology, New York University School of Medicine, New York, NY, USA.
- Department of Psychiatry, New York University School of Medicine, New York, NY, USA.
| |
Collapse
|
30
|
Thomas MH, Paris C, Magnien M, Colin J, Pelleïeux S, Coste F, Escanyé MC, Pillot T, Olivier JL. Dietary arachidonic acid increases deleterious effects of amyloid-β oligomers on learning abilities and expression of AMPA receptors: putative role of the ACSL4-cPLA 2 balance. ALZHEIMERS RESEARCH & THERAPY 2017; 9:69. [PMID: 28851448 PMCID: PMC5576249 DOI: 10.1186/s13195-017-0295-1] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/18/2016] [Accepted: 08/03/2017] [Indexed: 01/14/2023]
Abstract
Background Polyunsaturated fatty acids play a crucial role in neuronal function, and the modification of these compounds in the brain could have an impact on neurodegenerative diseases such as Alzheimer’s disease. Despite the fact that arachidonic acid is the second foremost polyunsaturated fatty acid besides docosahexaenoic acid, its role and the regulation of its transfer and mobilization in the brain are poorly known. Methods Two groups of 39 adult male BALB/c mice were fed with an arachidonic acid-enriched diet or an oleic acid-enriched diet, respectively, for 12 weeks. After 10 weeks on the diet, mice received intracerebroventricular injections of either NaCl solution or amyloid-β peptide (Aβ) oligomers. Y-maze and Morris water maze tests were used to evaluate short- and long-term memory. At 12 weeks on the diet, mice were killed, and blood, liver, and brain samples were collected for lipid and protein analyses. Results We found that the administration of an arachidonic acid-enriched diet for 12 weeks induced short-term memory impairment and increased deleterious effects of Aβ oligomers on learning abilities. These cognitive alterations were associated with modifications of expression of α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptors, postsynaptic density protein 95, and glial fibrillary acidic protein in mouse cortex or hippocampus by the arachidonic acid-enriched diet and Aβ oligomer administration. This diet also led to an imbalance between the main ω-6 fatty acids and the ω-3 fatty acids in favor of the first one in erythrocytes and the liver as well as in the hippocampal and cortical brain structures. In the cortex, the dietary arachidonic acid also induced an increase of arachidonic acid-containing phospholipid species in phosphatidylserine class, whereas intracerebroventricular injections modified several arachidonic acid- and docosahexaenoic acid-containing species in the four phospholipid classes. Finally, we observed that dietary arachidonic acid decreased the expression of the neuronal form of acyl-coenzyme A synthetase 4 in the hippocampus and increased the cytosolic phospholipase A2 activation level in the cortices of the mice. Conclusions Dietary arachidonic acid could amplify Aβ oligomer neurotoxicity. Its consumption could constitute a risk factor for Alzheimer’s disease in humans and should be taken into account in future preventive strategies. Its deleterious effect on cognitive capacity could be linked to the balance between arachidonic acid-mobilizing enzymes. Electronic supplementary material The online version of this article (doi:10.1186/s13195-017-0295-1) contains supplementary material, which is available to authorized users.
Collapse
Affiliation(s)
- Mélanie H Thomas
- Research unit on Animals and Functionality of Animal Products (URAFPA), Lorraine University, EA 3998, USC INRA 0340, 2, Avenue de la Forêt de Haye, TSA40602, F-54518, Vandœuvre-lès-Nancy, France
| | - Cédric Paris
- Laboratory of Biomolecules Engineering (LIBio), Lorraine University, 2, Avenue de la Forêt de Haye, TSA40602, F-54518, Vandœuvre-lès-Nancy, France
| | - Mylène Magnien
- Research unit on Animals and Functionality of Animal Products (URAFPA), Lorraine University, EA 3998, USC INRA 0340, 2, Avenue de la Forêt de Haye, TSA40602, F-54518, Vandœuvre-lès-Nancy, France
| | - Julie Colin
- Research unit on Animals and Functionality of Animal Products (URAFPA), Lorraine University, EA 3998, USC INRA 0340, 2, Avenue de la Forêt de Haye, TSA40602, F-54518, Vandœuvre-lès-Nancy, France
| | - Sandra Pelleïeux
- Research unit on Animals and Functionality of Animal Products (URAFPA), Lorraine University, EA 3998, USC INRA 0340, 2, Avenue de la Forêt de Haye, TSA40602, F-54518, Vandœuvre-lès-Nancy, France.,Biochemistry Department, Central Hospital, University Hospitals of Nancy, 24, avenue du Mal de Lattre de Tassigny, CO n°34, F-54018, Nancy, France
| | - Florence Coste
- Research unit on Animals and Functionality of Animal Products (URAFPA), Lorraine University, EA 3998, USC INRA 0340, 2, Avenue de la Forêt de Haye, TSA40602, F-54518, Vandœuvre-lès-Nancy, France
| | - Marie-Christine Escanyé
- Biochemistry Department, Central Hospital, University Hospitals of Nancy, 24, avenue du Mal de Lattre de Tassigny, CO n°34, F-54018, Nancy, France
| | - Thierry Pillot
- Synaging SAS, 2, rue du Doyen Marcel Roubault, 54518, Vandoeuvre-les-Nancy, France
| | - Jean-Luc Olivier
- Research unit on Animals and Functionality of Animal Products (URAFPA), Lorraine University, EA 3998, USC INRA 0340, 2, Avenue de la Forêt de Haye, TSA40602, F-54518, Vandœuvre-lès-Nancy, France. .,Biochemistry Department, Central Hospital, University Hospitals of Nancy, 24, avenue du Mal de Lattre de Tassigny, CO n°34, F-54018, Nancy, France.
| |
Collapse
|
31
|
Jay TR, von Saucken VE, Landreth GE. TREM2 in Neurodegenerative Diseases. Mol Neurodegener 2017; 12:56. [PMID: 28768545 PMCID: PMC5541421 DOI: 10.1186/s13024-017-0197-5] [Citation(s) in RCA: 256] [Impact Index Per Article: 36.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2017] [Accepted: 07/20/2017] [Indexed: 12/12/2022] Open
Abstract
TREM2 variants have been identified as risk factors for Alzheimer's disease (AD) and other neurodegenerative diseases (NDDs). Because TREM2 encodes a receptor exclusively expressed on immune cells, identification of these variants conclusively demonstrates that the immune response can play an active role in the pathogenesis of NDDs. These TREM2 variants also confer the highest risk for developing Alzheimer's disease of any risk factor identified in nearly two decades, suggesting that understanding more about TREM2 function could provide key insights into NDD pathology and provide avenues for novel immune-related NDD biomarkers and therapeutics. The expression, signaling and function of TREM2 in NDDs have been extensively investigated in an effort to understand the role of immune function in disease pathogenesis and progression. We provide a comprehensive review of our current understanding of TREM2 biology, including new insights into the regulation of TREM2 expression, and TREM2 signaling and function across NDDs. While many open questions remain, the current body of literature provides clarity on several issues. While it is still often cited that TREM2 expression is decreased by pro-inflammatory stimuli, it is now clear that this is true in vitro, but inflammatory stimuli in vivo almost universally increase TREM2 expression. Likewise, while TREM2 function is classically described as promoting an anti-inflammatory phenotype, more than half of published studies demonstrate a pro-inflammatory role for TREM2, suggesting that its role in inflammation is much more complex. Finally, these components of TREM2 biology are applied to a discussion of how TREM2 impacts NDD pathologies and the latest assessment of how these findings might be applied to immune-directed clinical biomarkers and therapeutics.
Collapse
Affiliation(s)
- Taylor R. Jay
- Department of Neurosciences, Case Western Reserve University, School of Medicine, 10900 Euclid Avenue, Cleveland, OH 44106 USA
| | - Victoria E. von Saucken
- Department of Neurosciences, Case Western Reserve University, School of Medicine, 10900 Euclid Avenue, Cleveland, OH 44106 USA
- Stark Neurosciences Research Institute, Indiana University School of Medicine, 320 W 15th Street, Indianapolis, IN 46202 USA
| | - Gary E. Landreth
- Department of Neurosciences, Case Western Reserve University, School of Medicine, 10900 Euclid Avenue, Cleveland, OH 44106 USA
- Stark Neurosciences Research Institute, Indiana University School of Medicine, 320 W 15th Street, Indianapolis, IN 46202 USA
| |
Collapse
|
32
|
Aβ truncated species: Implications for brain clearance mechanisms and amyloid plaque deposition. Biochim Biophys Acta Mol Basis Dis 2017; 1864:208-225. [PMID: 28711595 DOI: 10.1016/j.bbadis.2017.07.005] [Citation(s) in RCA: 46] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2017] [Revised: 06/24/2017] [Accepted: 07/11/2017] [Indexed: 12/14/2022]
Abstract
Extensive parenchymal and vascular Aβ deposits are pathological hallmarks of Alzheimer's disease (AD). Besides classic full-length peptides, biochemical analyses of brain deposits have revealed high degree of Aβ heterogeneity likely resulting from the action of multiple proteolytic enzymes. In spite of the numerous studies focusing in Aβ, the relevance of N- and C-terminal truncated species for AD pathogenesis remains largely understudied. In the present work, using novel antibodies specifically recognizing Aβ species N-terminally truncated at position 4 or C-terminally truncated at position 34, we provide a clear assessment of the differential topographic localization of these species in AD brains and transgenic models. Based on their distinct solubility, brain N- and C-terminal truncated species were extracted by differential fractionation and identified via immunoprecipitation coupled to mass spectrometry analysis. Biochemical/biophysical studies with synthetic homologues further confirmed the different solubility properties and contrasting fibrillogenic characteristics of the truncated species composing the brain Aβ peptidome. Aβ C-terminal degradation leads to the production of more soluble fragments likely to be more easily eliminated from the brain. On the contrary, N-terminal truncation at position 4 favors the formation of poorly soluble, aggregation prone peptides with high amyloidogenic propensity and the potential to exacerbate the fibrillar deposits, self-perpetuating the amyloidogenic loop. Detailed assessment of the molecular diversity of Aβ species composing interstitial fluid and amyloid deposits at different disease stages, as well as the evaluation of the truncation profile during various pharmacologic approaches will provide a comprehensive understanding of the still undefined contribution of Aβ truncations to the disease pathogenesis and their potential as novel therapeutic targets.
Collapse
|
33
|
Kim EJ, Yang SJ. Nicotinamide Reduces Amyloid Precursor Protein and Presenilin 1 in Brain Tissues of Amyloid Beta-Tail Vein Injected Mice. Clin Nutr Res 2017; 6:130-135. [PMID: 28503509 PMCID: PMC5426212 DOI: 10.7762/cnr.2017.6.2.130] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2017] [Revised: 04/20/2017] [Accepted: 04/23/2017] [Indexed: 02/07/2023] Open
Abstract
The purpose of this study is to investigate whether nicotinic acid (NA) and nicotinamide (NAM) reduce the Alzheimer disease (AD)-related gene expression in brain tissues of amyloid beta (Aβ)-injected mice. Male Crj:CD1 (ICR) mice were divided into 6 treatment groups; 1) control, 2) Aβ control, 3) Aβ + NA 20 mg/kg/day (NA20), 4) Aβ + NA40, 5) Aβ + NAM 200 mg/kg/day (NAM200), and 6) Aβ + NAM400. After 1-week acclimation period, the mice orally received NA or NAM once a day for a total of 7 successive days. On day 7, biotinylated Aβ42 was injected into mouse tail vein. At 5 hours after the injection, blood and tissues were collected. Aβ42 injection was confirmed by Western blot analysis of Aβ42 protein in brain tissue. NAM400 pre-treatment significantly reduced the gene expression of amyloid precursor protein and presenilin 1 in brain tissues. And, NAM200 and NAM400 pre-treatments significantly increased sirtuin 1 expression in brain tissues, which is accompanied by the decreased brain expression of nuclear factor kappa B by 2 doses of NAM. Increased expression of AD-related genes was attenuated by the NAM treatment, which suggests that NAM supplementation may be a potential preventive strategy against AD-related deleterious changes.
Collapse
Affiliation(s)
- Eun Jin Kim
- Department of Food and Nutrition, Chonnam National University, Gwangju 61186, Korea
| | - Soo Jin Yang
- Department of Food and Nutrition, Seoul Women's University, Seoul 01797, Korea
| |
Collapse
|