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Sinclair AJ, Wang Y, Li D. What Is the Evidence for Dietary-Induced DHA Deficiency in Human Brains? Nutrients 2022; 15:nu15010161. [PMID: 36615819 PMCID: PMC9824463 DOI: 10.3390/nu15010161] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2022] [Revised: 12/20/2022] [Accepted: 12/27/2022] [Indexed: 12/31/2022] Open
Abstract
Docosahexaenoic acid (DHA) is a major constituent of neural and visual membranes and is required for optimal neural and visual function. DHA is derived from food or by endogenous synthesis from α-linolenic acid (ALA), an essential fatty acid. Low blood levels of DHA in some westernised populations have led to speculations that child development disorders and various neurological conditions are associated with sub-optimal neural DHA levels, a proposition which has been supported by the supplement industry. This review searched for evidence of deficiency of DHA in human populations, based on elevated levels of the biochemical marker of n-3 deficiency, docosapentaenoic acid (22:5n-6). Three scenarios/situations were identified for the insufficient supply of DHA, namely in the brain of new-born infants fed with high-linoleic acid (LA), low-ALA formulas, in cord blood of women at birth who were vegetarians and in the milk of women from North Sudan. Twenty post-mortem brain studies from the developed world from adults with various neurological disorders revealed no evidence of raised levels of 22:5n-6, even in the samples with reduced DHA levels compared with control subjects. Human populations most likely at risk of n-3 deficiency are new-born and weanling infants, children and adolescents in areas of dryland agriculture, in famines, or are refugees, however, these populations have rarely been studied. This is an important topic for future research.
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Affiliation(s)
- Andrew J. Sinclair
- Department of Nutrition, Dietetics and Food, School of Clinical Sciences, Monash University, Notting Hill, VIC 3168, Australia
- Faculty of Health, Deakin University, Burwood, VIC 3152, Australia
- Correspondence: ; Tel.: +61-(0)414-906-341
| | - Yonghua Wang
- School of Food Science and Engineering, South China University of Technology, Guangzhou 510641, China
| | - Duo Li
- Institute of Nutrition & Health, College of Public Health, Qingdao University, Qingdao 266071, China
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2
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Hidalgo-Lanussa O, Baez-Jurado E, Echeverria V, Ashraf GM, Sahebkar A, Garcia-Segura LM, Melcangi RC, Barreto GE. Lipotoxicity, neuroinflammation, glial cells and oestrogenic compounds. J Neuroendocrinol 2020; 32:e12776. [PMID: 31334878 DOI: 10.1111/jne.12776] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/15/2019] [Revised: 07/16/2019] [Accepted: 07/17/2019] [Indexed: 02/07/2023]
Abstract
The high concentrations of free fatty acids as a consequence of obesity and being overweight have become risk factors for the development of different diseases, including neurodegenerative ailments. Free fatty acids are strongly related to inflammatory events, causing cellular and tissue alterations in the brain, including cell death, deficits in neurogenesis and gliogenesis, and cognitive decline. It has been reported that people with a high body mass index have a higher risk of suffering from Alzheimer's disease. Hormones such as oestradiol not only have beneficial effects on brain tissue, but also exert some adverse effects on peripheral tissues, including the ovary and breast. For this reason, some studies have evaluated the protective effect of oestrogen receptor (ER) agonists with more specific tissue activities, such as the neuroactive steroid tibolone. Activation of ERs positively affects the expression of pro-survival factors and cell signalling pathways, thus promoting cell survival. This review aims to discuss the relationship between lipotoxicity and the development of neurodegenerative diseases. We also elaborate on the cellular and molecular mechanisms involved in neuroprotection induced by oestrogens.
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Affiliation(s)
- Oscar Hidalgo-Lanussa
- Departamento de Nutrición y Bioquímica, Facultad de Ciencias, Pontificia Universidad Javeriana, Bogotá, Colombia
| | - Eliana Baez-Jurado
- Departamento de Nutrición y Bioquímica, Facultad de Ciencias, Pontificia Universidad Javeriana, Bogotá, Colombia
| | - Valentina Echeverria
- Facultad de Ciencias de la Salud, Universidad San Sebastián, Concepción, Chile
- Bay Pines VA Healthcare System, Research and Development, Bay Pines, FL, USA
| | - Ghulam Md Ashraf
- King Fahd Medical Research Center, King Abdulaziz University, Jeddah, Saudi Arabia
| | - Amirhossein Sahebkar
- Neurogenic Inflammation Research Center, Mashhad University of Medical Sciences, Mashhad, Iran
- Biotechnology Research Center, Pharmaceutical Technology Institute, Mashhad University of Medical Sciences, Mashhad, Iran
- School of Pharmacy, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Luis Miguel Garcia-Segura
- Instituto Cajal, CSIC, Madrid, Spain
- Centro de Investigación Biomédica en Red Fragilidad y Envejecimiento Saludable (CIBERFES), Instituto de Salud Carlos III, Madrid, Spain
| | - Roberto C Melcangi
- Dipartimento di Scienze Farmacologiche e Biomolecolari, Università degli Studi di Milano, Milano, Italy
| | - George E Barreto
- Departamento de Nutrición y Bioquímica, Facultad de Ciencias, Pontificia Universidad Javeriana, Bogotá, Colombia
- Department of Biological Sciences, University of Limerick, Limerick, Ireland
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3
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Pan Y, Morris ER, Scanlon MJ, Marriott PJ, Porter CJH, Nicolazzo JA. Dietary docosahexaenoic acid supplementation enhances expression of fatty acid-binding protein 5 at the blood-brain barrier and brain docosahexaenoic acid levels. J Neurochem 2018; 146:186-197. [DOI: 10.1111/jnc.14342] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2017] [Revised: 03/20/2018] [Accepted: 03/21/2018] [Indexed: 11/29/2022]
Affiliation(s)
- Yijun Pan
- Drug Delivery, Disposition and Dynamics; Monash Institute of Pharmaceutical Sciences; Monash University; Parkville Victoria Australia
| | - Elonie R. Morris
- Drug Delivery, Disposition and Dynamics; Monash Institute of Pharmaceutical Sciences; Monash University; Parkville Victoria Australia
| | - Martin J. Scanlon
- Medicinal Chemistry; Monash Institute of Pharmaceutical Sciences; Monash University; Parkville Victoria Australia
| | - Philip J. Marriott
- Australian Centre for Research on Separation Science; School of Chemistry; Monash University; Clayton Victoria Australia
| | - Christopher J. H. Porter
- Drug Delivery, Disposition and Dynamics; Monash Institute of Pharmaceutical Sciences; Monash University; Parkville Victoria Australia
- ARC Centre of Excellence in Convergent Bio-Nano Science and Technology; Monash Institute of Pharmaceutical Sciences; Monash University; Parkville Victoria Australia
| | - Joseph A. Nicolazzo
- Drug Delivery, Disposition and Dynamics; Monash Institute of Pharmaceutical Sciences; Monash University; Parkville Victoria Australia
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4
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Pan Y, Choy KHC, Marriott PJ, Chai SY, Scanlon MJ, Porter CJH, Short JL, Nicolazzo JA. Reduced blood-brain barrier expression of fatty acid-binding protein 5 is associated with increased vulnerability of APP/PS1 mice to cognitive deficits from low omega-3 fatty acid diets. J Neurochem 2017; 144:81-92. [DOI: 10.1111/jnc.14249] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2017] [Revised: 10/18/2017] [Accepted: 10/25/2017] [Indexed: 01/08/2023]
Affiliation(s)
- Yijun Pan
- Drug Delivery, Disposition and Dynamics; Monash Institute of Pharmaceutical Sciences; Monash University; Parkville Vic. Australia
| | - Kwok H. C. Choy
- Drug Discovery Biology; Monash Institute of Pharmaceutical Sciences; Monash University; Parkville Vic. Australia
| | - Philip J. Marriott
- Australian Centre for Research on Separation Science; School of Chemistry; Monash University; Vic. Australia
| | - Siew Y. Chai
- Department of Physiology; Biomedicine Discovery Institute; Monash University; Clayton Vic. Australia
| | - Martin J. Scanlon
- Medicinal Chemistry; Monash Institute of Pharmaceutical Sciences; Monash University; Parkville Vic. Australia
| | - Christopher J. H. Porter
- Drug Delivery, Disposition and Dynamics; Monash Institute of Pharmaceutical Sciences; Monash University; Parkville Vic. Australia
- ARC Centre of Excellence in Convergent Bio-Nano Science and Technology; Monash Institute of Pharmaceutical Sciences; Monash University; Parkville Vic. Australia
| | - Jennifer L. Short
- Drug Discovery Biology; Monash Institute of Pharmaceutical Sciences; Monash University; Parkville Vic. Australia
| | - Joseph A. Nicolazzo
- Drug Delivery, Disposition and Dynamics; Monash Institute of Pharmaceutical Sciences; Monash University; Parkville Vic. Australia
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5
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Fatty Acid-Binding Protein 5 at the Blood-Brain Barrier Regulates Endogenous Brain Docosahexaenoic Acid Levels and Cognitive Function. J Neurosci 2017; 36:11755-11767. [PMID: 27852782 DOI: 10.1523/jneurosci.1583-16.2016] [Citation(s) in RCA: 51] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2016] [Revised: 09/22/2016] [Accepted: 09/24/2016] [Indexed: 11/21/2022] Open
Abstract
Fatty acid-binding protein 5 (FABP5) at the blood-brain barrier contributes to the brain uptake of docosahexaenoic acid (DHA), a blood-derived polyunsaturated fatty acid essential for maintenance of cognitive function. Given the importance of DHA in cognition, the aim of this study was to investigate whether deletion of FABP5 results in cognitive dysfunction and whether this is associated with reduced brain endothelial cell uptake of exogenous DHA and subsequent attenuation in the brain levels of endogenous DHA. Cognitive function was assessed in male and female FABP5+/+ and FABP5-/- mice using a battery of memory paradigms. FABP5-/- mice exhibited impaired working memory and short-term memory, and these cognitive deficits were associated with a 14.7 ± 5.7% reduction in endogenous brain DHA levels. The role of FABP5 in the blood-brain barrier transport of DHA was assessed by measuring 14C-DHA uptake into brain endothelial cells and capillaries isolated from FABP5+/+ and FABP5-/- mice. In line with a crucial role of FABP5 in the brain uptake of DHA, 14C-DHA uptake into brain endothelial cells and brain capillaries of FABP5-/- mice was reduced by 48.4 ± 14.5% and 14.0 ± 4.2%, respectively, relative to those of FABP5+/+ mice. These results strongly support the hypothesis that FABP5 is essential for maintaining brain endothelial cell uptake of DHA, and that cognitive deficits observed in FABP5-/- mice are associated with reduced CNS access of DHA. SIGNIFICANCE STATEMENT Genetic deletion of fatty acid-binding protein 5 (FABP5) in mice reduces uptake of exogenous docosahexaenoic acid (DHA) into brain endothelial cells and brain capillaries and reduces brain parenchymal levels of endogenous DHA. Therefore, FABP5 in the brain endothelial cell is a crucial contributor to the brain levels of DHA. Critically, lowered brain DHA levels in FABP5-/- mice occurred in tandem with cognitive deficits in a battery of memory paradigms. This study provides evidence of a critical role for FABP5 in the maintenance of cognitive function via regulating the brain uptake of DHA, and suggests that upregulation of FABP5 in neurodegenerative diseases, where brain DHA levels are possibly diminished (e.g., Alzheimer's disease), may provide a novel therapeutic approach for restoring cognitive function.
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Schut MH, Patassini S, Kim EH, Bullock J, Waldvogel HJ, Faull RLM, Pepers BA, den Dunnen JT, van Ommen GJB, van Roon-Mom WMC. Effect of post-mortem delay on N-terminal huntingtin protein fragments in human control and Huntington disease brain lysates. PLoS One 2017; 12:e0178556. [PMID: 28570578 PMCID: PMC5453542 DOI: 10.1371/journal.pone.0178556] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2016] [Accepted: 05/15/2017] [Indexed: 11/29/2022] Open
Abstract
Huntington disease is associated with elongation of a CAG repeat in the HTT gene that results in a mutant huntingtin protein. Several studies have implicated N-terminal huntingtin protein fragments in Huntington disease pathogenesis. Ideally, these fragments are studied in human brain tissue. However, the use of human brain tissue comes with certain unavoidable variables such as post mortem delay, artefacts from freeze-thaw cycles and subject-to-subject variation. Knowledge on how these variables might affect N-terminal huntingtin protein fragments in post mortem human brain is important for a proper interpretation of study results. The effect of post mortem delay on protein in human brain is known to vary depending on the protein of interest. In the present study, we have assessed the effect of post mortem delay on N-terminal huntingtin protein fragments using western blot. We mimicked post mortem delay in one individual control case and one individual Huntington disease case with low initial post mortem delay. The influence of subject-to-subject variation on N-terminal huntingtin fragments was assessed in human cortex and human striatum using two cohorts of control and Huntington disease subjects. Our results show that effects of post mortem delay on N-terminal huntingtin protein fragments are minor in our individual subjects. Additionally, one freeze-thaw cycle decreases the huntingtin western blot signal intensity in the cortex control subject, but does not introduce additional N-terminal huntingtin fragments. Our results suggest that subject-to-subject variation contributes more to variability in N-terminal huntingtin fragments than post mortem delay.
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Affiliation(s)
- Menno H. Schut
- Department of Human Genetics, Leiden University Medical Center, Leiden, The Netherlands
| | - Stefano Patassini
- Centre for Brain Research and Department of Anatomy with Radiology, University of Auckland, Auckland, New Zealand
| | - Eric H. Kim
- Centre for Brain Research and Department of Anatomy with Radiology, University of Auckland, Auckland, New Zealand
| | - Jocelyn Bullock
- Centre for Brain Research and Department of Anatomy with Radiology, University of Auckland, Auckland, New Zealand
| | - Henry J. Waldvogel
- Centre for Brain Research and Department of Anatomy with Radiology, University of Auckland, Auckland, New Zealand
| | - Richard L. M. Faull
- Centre for Brain Research and Department of Anatomy with Radiology, University of Auckland, Auckland, New Zealand
| | - Barry A. Pepers
- Department of Human Genetics, Leiden University Medical Center, Leiden, The Netherlands
| | - Johan T. den Dunnen
- Department of Human Genetics, Leiden University Medical Center, Leiden, The Netherlands
- Leiden Genome Technology Center, Leiden University Medical Center, Leiden, The Netherlands
| | - Gert-Jan B. van Ommen
- Department of Human Genetics, Leiden University Medical Center, Leiden, The Netherlands
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7
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Cortie CH, Hulbert AJ, Hancock SE, Mitchell TW, McAndrew D, Else PL. Of mice, pigs and humans: An analysis of mitochondrial phospholipids from mammals with very different maximal lifespans. Exp Gerontol 2015; 70:135-43. [PMID: 26315290 DOI: 10.1016/j.exger.2015.08.011] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2014] [Revised: 08/19/2015] [Accepted: 08/20/2015] [Indexed: 12/20/2022]
Abstract
The maximal lifespan (MLS) of mammals is inversely correlated with the peroxidation index, a measure of the proportion and level of unsaturation of polyunsaturated fatty acids (PUFA) in membranes. This relationship is likely related to the fact that PUFA are highly susceptible to damage by peroxidation. Previous comparative work has examined membrane composition at the level of fatty acids, and relatively little is known regarding the distribution of PUFA across phospholipid classes or phospholipid molecules. In addition, data for humans is extremely rare in this area. Here we present the first shotgun lipidomics analysis of mitochondrial membranes and the peroxidation index of skeletal muscle, liver, and brain in three mammals that span the range of mammalian longevity. The species compared were mice (MLS of 4 years), pigs (MLS of 27 years), and humans (MLS of 122 years). Mouse mitochondria contained highly unsaturated PUFA in all phospholipid classes. Human mitochondria had lower PUFA content and a lower degree of unsaturation of PUFA. Pig mitochondria shared characteristics of both mice and humans. We found that membrane susceptibility to peroxidation was primarily determined by a limited number of phospholipid molecules that differed between both tissues and species.
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Affiliation(s)
- Colin H Cortie
- School of Medicine, University of Wollongong, Wollongong, NSW 2522, Australia; Illawarra Health and Medical Research Institute (IHMRI), University of Wollongong, Wollongong, NSW 2522, Australia.
| | - Anthony J Hulbert
- School of Biology, University of Wollongong, Wollongong, NSW 2522, Australia
| | - Sarah E Hancock
- School of Medicine, University of Wollongong, Wollongong, NSW 2522, Australia; Illawarra Health and Medical Research Institute (IHMRI), University of Wollongong, Wollongong, NSW 2522, Australia
| | - Todd W Mitchell
- School of Medicine, University of Wollongong, Wollongong, NSW 2522, Australia; Illawarra Health and Medical Research Institute (IHMRI), University of Wollongong, Wollongong, NSW 2522, Australia
| | - Darryl McAndrew
- School of Medicine, University of Wollongong, Wollongong, NSW 2522, Australia
| | - Paul L Else
- School of Medicine, University of Wollongong, Wollongong, NSW 2522, Australia; Illawarra Health and Medical Research Institute (IHMRI), University of Wollongong, Wollongong, NSW 2522, Australia
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8
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Samarasekera N, Al-Shahi Salman R, Huitinga I, Klioueva N, McLean CA, Kretzschmar H, Smith C, Ironside JW. Brain banking for neurological disorders. Lancet Neurol 2013; 12:1096-105. [PMID: 24074724 DOI: 10.1016/s1474-4422(13)70202-3] [Citation(s) in RCA: 69] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Brain banks are used to gather, store, and provide human brain tissue for research and have been fundamental to improving our knowledge of the brain in health and disease. To maintain this role, the legal and ethical issues relevant to the operations of brain banks need to be more widely understood. In recent years, researchers have reported that shortages of high-quality brain tissue samples from both healthy and diseased people have impaired their efforts. Closer collaborations between brain banks and improved strategies for brain donation programmes will be essential to overcome these problems as the demand for brain tissue increases and new research techniques become more widespread, with the potential for substantial scientific advances in increasingly common neurological disorders.
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Affiliation(s)
- Neshika Samarasekera
- Division of Clinical Neurosciences, Centre for Clinical Brain Sciences, University of Edinburgh, Edinburgh, UK
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9
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An Improved High-Throughput Lipid Extraction Method for the Analysis of Human Brain Lipids. Lipids 2013; 48:307-18. [DOI: 10.1007/s11745-013-3760-z] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2012] [Accepted: 12/24/2012] [Indexed: 10/27/2022]
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10
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Abstract
Bipolar and major depressive disorders are essentially relapsing and remitting disorders of affect with nearly full recovery between episodes. Although the underlying molecular mechanisms remain unclear, myelin-related abnormalities have long been suspected. Here, using novel statistical analysis, we show that subtle but significant abnormalities exist in the composition of fatty acids (FAs), including docosapentaenoic acid (22:5n-3), one of the omega-3 polyunsaturated FAs, found in the post-mortem frontopolar cortex (FPC) of subjects with bipolar or major depressive disorders, although not in those with schizophrenia. These abnormalities were all aggravated in a myelin level-dependent manner, suggesting their close relationship with myelination. Animal studies have further revealed that chronic antidepressant treatment induces robust changes in brain FA metabolism, but contributes only part of the abnormalities found in the affective disorder brains. These findings indicate that the pathophysiology of affective disorders involves an unknown type of perturbed myelination in the FPC that may serve as a novel diagnostic and therapeutic target.
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Ashby EL, Love S, Kehoe PG. Assessment of activation of the plasma kallikrein-kinin system in frontal and temporal cortex in Alzheimer's disease and vascular dementia. Neurobiol Aging 2010; 33:1345-55. [PMID: 21074291 DOI: 10.1016/j.neurobiolaging.2010.09.024] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2010] [Revised: 09/20/2010] [Accepted: 09/26/2010] [Indexed: 01/01/2023]
Abstract
Decreased cerebral blood flow and blood-brain barrier disruption are features of Alzheimer's disease (AD). The plasma kallikrein-kinin system modulates cerebrovascular tone through release of vasoactive bradykinin (BK). Cerebroventricular infusion of Aβ1-40 enhances BK release, suggesting that the activity of this system may be elevated in AD. We investigated the profile of the activating protease of this system, plasma kallikrein (PK), in frontal and temporal brain tissue from postmortem confirmed cases of AD, vascular dementia (VaD), and controls. Measurements of neuron specific enolase messenger ribonucleic acid (mRNA) and protein were used to adjust for neuronal loss. Adjusted PK mRNA was significantly increased in the frontal cortex in AD, and the frontal and temporal cortex in VaD. Similar trends were seen for PK protein level in AD and VaD. PK activity was significantly increased in the frontal and temporal cortex in AD. Increased PK activity in AD is likely to contribute to increased BK release and may thereby influence cerebral blood flow and vascular permeability.
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Affiliation(s)
- Emma L Ashby
- Dementia Research Group, Institute of Clinical Neurosciences, School of Clinical Sciences, University of Bristol, Bristol, UK
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12
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Ashby EL, Kehoe PG, Love S. Kallikrein-related peptidase 6 in Alzheimer's disease and vascular dementia. Brain Res 2010; 1363:1-10. [PMID: 20846516 DOI: 10.1016/j.brainres.2010.09.017] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2010] [Revised: 09/03/2010] [Accepted: 09/06/2010] [Indexed: 11/30/2022]
Abstract
Human kallikrein-related peptidase 6 (KLK6) is highly expressed in the central nervous system. Although the physiological roles of this serine protease are unknown, in vitro substrates include amyloid precursor protein and components of the extracellular matrix, which are altered in neurological disease, particularly Alzheimer's disease (AD). We have compared KLK6 expression in post-mortem brain tissue in AD, vascular dementia (VaD) and controls. We studied the distribution of KLK6 in the temporal cortex and white matter by immunohistochemistry, and measured KLK6 mRNA and protein levels in the frontal and temporal cortex from 15 AD, 15 VaD and 15 control brains. Immunohistochemistry showed KLK6 to be restricted to endothelial cells. After adjustment for variations in vessel density by measurement of factor VIII-related antigen, we found KLK6 protein and mRNA levels to be significantly decreased in the frontal but not the temporal cortex in AD. In VaD, KLK6 protein level was significantly increased in the frontal cortex. Our findings suggest that an altered KLK6 expression may contribute to vascular abnormalities in AD and VaD.
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Affiliation(s)
- Emma L Ashby
- Dementia Research Group, Institute of Clinical Neurosciences, Clinical Science at North Bristol, University of Bristol, UK
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13
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Fraser T, Tayler H, Love S. Fatty acid composition of frontal, temporal and parietal neocortex in the normal human brain and in Alzheimer's disease. Neurochem Res 2009; 35:503-13. [PMID: 19904605 DOI: 10.1007/s11064-009-0087-5] [Citation(s) in RCA: 122] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/24/2009] [Indexed: 11/29/2022]
Abstract
Dietary omega3-polyunsaturated fatty acids are thought to influence the risk of Alzheimer's disease (AD), and supplemental docosahexaenoic acid (DHA; 22:6n-3) has been reported to reduce neurodegeneration in mouse models of AD. We have analysed the fatty acid composition of frontal, temporal and parietal neocortex in 58 normal and 114 AD brains. Significant reductions were found for stearic acid (18:0) in frontal and temporal cortex and arachidonic acid (20:4n-6) in temporal cortex in AD, and increases in oleic acid in frontal and temporal cortex (18:1n-9) and palmitic acid (16:0) in parietal cortex. DHA level varied more in AD than controls but the mean values were not significantly different. Fatty acid composition was not related to APOE genotype, age, gender or post-mortem delay. Further research is needed to distinguish between alterations that are secondary to AD and those that contribute to the disease process.
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Affiliation(s)
- Thomas Fraser
- Dementia Research Group, Institute of Clinical Neurosciences, University of Bristol, Frenchay Hospital, Bristol, BS16 1LE, UK
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14
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van Helmond Z, Miners JS, Kehoe PG, Love S. Oligomeric Abeta in Alzheimer's disease: relationship to plaque and tangle pathology, APOE genotype and cerebral amyloid angiopathy. Brain Pathol 2009; 20:468-80. [PMID: 19725829 DOI: 10.1111/j.1750-3639.2009.00321.x] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Despite accumulating evidence of a central role for oligomeric amyloid beta (Abeta) in the pathogenesis of Alzheimer's Disease (AD), there is scant information on the relationship between the levels and distribution of oligomeric Abeta and those of other neurodegenerative abnormalities in AD. In the present study, we have found oligomeric Abeta to be associated with both diffuse and neuritic plaques (mostly co-localized with Abeta(1-42)) and with cerebrovascular deposits of Abeta in paraffin sections of formalin-fixed human brain tissue. The amount of oligomeric Abeta that was labeled in the sections correlated with total Abeta plaque load, but not phospho-tau load, cerebral amyloid angiopathy (CAA) severity or APOE genotype. Although soluble, oligomeric and insoluble Abeta levels were all significantly increased in AD brain homogenates, case-to-case variation and overlap between AD and controls were considerable. Over the age-range studied (43-98 years), the levels of soluble Abeta, oligomeric Abeta(42), oligomeric Abeta(40) and insoluble Abeta did not vary significantly with age. Oligomeric Abeta(1-42) and insoluble Abeta levels were significantly higher in women. Overall, the level of insoluble Abeta, but neither oligomeric nor soluble Abeta, was associated with Braak stage, CAA severity and APOEepsilon4 frequency, raising questions as to the role of soluble and oligomeric Abeta in the progression of AD.
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Affiliation(s)
- Zoë van Helmond
- Dementia Research Group, Institute of Clinical Neurosciences, Clinical Science at North Bristol, University of Bristol, Bristol, UK.
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