Alzheimer Disease: Lees AJ

Morris HR, Wood NW, Lees AJ. · National Hospital for Neurology and Neurosurgery, London, UK. · Postgrad Med J. · Pubmed #10621897 links to  free full text

Abstract: Progressive supranuclear palsy is a neurodegenerative disease which affects the brainstem and basal ganglia. Patients present with disturbance of balance, a disorder of downward gaze and L-DOPA-unresponsive parkinsonism and usually develop progressive dysphagia and dysarthria leading to death from the complications of immobility and aspiration. Treatment remains largely supportive but, potentially, treatments based on cholinergic therapy may be useful. As in Alzheimer's disease, the neuronal degeneration is associated with the deposition of hyperphosphorylated tau protein as neurofibrillary tangles but there are important distinctions between the two diseases. Evidence from familial fronto-temporal dementia with parkinsonism linked to chromosome 17 suggests that tau protein deposition is a primary pathogenic event in some neurodegenerative diseases. The understanding of the mechanism of tau deposition in progressive supranuclear palsy is likely to be of importance in unravelling its aetiology.

Healy DG, Falchi M, O'Sullivan SS, Bonifati V, Durr A, Bressman S, Brice A, Aasly J, Zabetian CP, Goldwurm S, Ferreira JJ, Tolosa E, Kay DM, Klein C, Williams DR, Marras C, Lang AE, Wszolek ZK, Berciano J, Schapira AH, Lynch T, Bhatia KP, Gasser T, Lees AJ, Wood NW, Anonymous00013. · Department of Clinical Neurosciences, Institute of Neurology, University College London, London, UK. · Lancet Neurol. · Pubmed #18539534 No free full text.

Abstract: BACKGROUND: Mutations in LRRK2, the gene that encodes leucine-rich repeat kinase 2, are a cause of Parkinson's disease (PD). The International LRRK2 Consortium was established to answer three key clinical questions: can LRRK2-associated PD be distinguished from idiopathic PD; which mutations in LRRK2 are pathogenic; and what is the age-specific cumulative risk of PD for individuals who inherit or are at risk of inheriting a deleterious mutation in LRRK2? METHODS: Researchers from 21 centres across the world collaborated on this study. The frequency of the common LRRK2 Gly2019Ser mutation was estimated on the basis of data from 24 populations worldwide, and the penetrance of the mutation was defined in 1045 people with mutations in LRRK2 from 133 families. The LRRK2 phenotype was defined on the basis of 59 motor and non-motor symptoms in 356 patients with LRRK2-associated PD and compared with the symptoms of 543 patients with pathologically proven idiopathic PD. FINDINGS: Six mutations met the consortium's criteria for being proven pathogenic. The frequency of the common LRRK2 Gly2019Ser mutation was 1% of patients with sporadic PD and 4% of patients with hereditary PD; the frequency was highest in the middle east and higher in southern Europe than in northern Europe. The risk of PD for a person who inherits the LRRK2 Gly2019Ser mutation was 28% at age 59 years, 51% at 69 years, and 74% at 79 years. The motor symptoms (eg, disease severity, rate of progression, occurrence of falls, and dyskinesia) and non-motor symptoms (eg, cognition and olfaction) of LRRK2-associated PD were more benign than those of idiopathic PD. INTERPRETATION: Mutations in LRRK2 are a clinically relevant cause of PD that merit testing in patients with hereditary PD and in subgroups of patients with PD. However, this knowledge should be applied with caution in the diagnosis and counselling of patients. FUNDING: UK Medical Research Council; UK Parkinson's Disease Society; UK Brain Research Trust; Internationaal Parkinson Fonds; Volkswagen Foundation; National Institutes of Health: National Institute of Neurological Disorders and Stroke and National Institute of Aging; Udall Parkinson's Disease Centre of Excellence; Pacific Alzheimer Research Foundation Centre; Italian Telethon Foundation; Fondazione Grigioni per il Morbo di Parkinson; Michael J Fox Foundation for Parkinson's Research; Safra Global Genetics Consortium; US Department of Veterans Affairs; French Agence Nationale de la Recherche.

Warren NM, Piggott MA, Lees AJ, Perry EK, Burn DJ. · Wolfson Research Centre, Newcastle University Institute for Ageing and Health, Campus for Ageing and Vitality, Newcastle General Hospital, Westgate Road, Newcastle upon Tyne, UK. · J Chem Neuroanat. · Pubmed #18282687 No free full text.

Abstract: Progressive supranuclear palsy (PSP) is a neurodegenerative disease characterised clinically by motor and cognitive symptoms. Cholinergic dysfunction is thought to be responsible for much of the cognitive symptomatology. To date, however, cholinergic replacement therapies have been ineffective. We used receptor specific radioligand autoradiography to measure M1, M2, and M4 receptor density, and the functional status of the principal cortical subtype, M1, in the frontal cortex in post-mortem brain tissue of PSP patients (n=14). Results were compared to normal controls (n=17) and patients with dementia with Lewy bodies (DLB, n=12) and Alzheimer's disease (AD, n=15). In PSP there were no changes in M1, M2, or M4 muscarinic receptor densities or M1 coupling. DLB cases showed a non-significant increase in M1 receptors. In AD there was a reduction in M1 receptors and coupling in most frontal cortical areas which reached significance, compared to DLB, for M1 receptors in the cingulate (p<0.05). We conclude from this first systematic study of cortical muscarinic receptors in PSP that functioning cortical muscarinic receptors are preserved. A further, larger trial of cholinergic therapy, such as an M1 agonist, may be warranted.

Lashley T, Revesz T, Plant G, Bandopadhyay R, Lees AJ, Frangione B, Wood NW, de Silva R, Ghiso J, Rostagno A, Holton JL. · Queen Square Brain Bank, Department of Molecular Neuroscience, UCL Institute of Neurology, University College London, London, UK. · Neuropathol Appl Neurobiol. · Pubmed #18282158 No free full text.

Abstract: INTRODUCTION: Two different disease-specific mutations in the BRI2 gene, situated on chromosome 13, have been identified as giving rise to familial British dementia (FBD) and familial Danish dementia (FDD). Each mutation results in extension of the open reading frame generating the disease-specific precursor proteins which are cleaved by furin-like proteolysis releasing the amyloidogenic C-terminal peptides ABri and ADan in FBD and FDD, respectively. MATERIAL AND METHODS: To understand the mechanism of the formation of amyloid lesions in FBD, we studied the origin of the precursor proteins and furin in the human brain. We used control brains, cases of sporadic Alzheimer's disease (AD), variant AD with cotton wool plaques and FBD to study BRI2 mRNA expression using in situ hybridization. Furin and BRI2 protein expression was investigated using Western blotting and immunohistochemistry. RESULTS: BRI2 mRNA and BRI2 protein are widely expressed primarily by neurones and glia and are deposited in the amyloid lesions in FBD. They were, however, not expressed by cerebrovascular components. Furin expression showed a similar pattern except that it was also present in cerebrovascular smooth muscle cells. CONCLUSIONS: These findings suggest that neurones and glia and are a major source of BRI2 protein and that in FBD, the mutated precursor protein may undergo furin cleavage within neurones to produce the amyloid peptide ABri. The failure to demonstrate BRI2 in blood vessels under the conditions tested suggests that vascular amyloid peptide production does not contribute significantly to cerebral amyloid angiopathy (CAA) in FBD and FDD, lending indirect support to the drainage hypothesis of CAA.

Warren NM, Piggott MA, Lees AJ, Burn DJ. · From the Institute for Ageing and Heath, Newcastle General Hospital, London, UK. · J Neuropathol Exp Neurol. · Pubmed #17483697 No free full text.

Abstract: ABSTRACT: Progressive supranuclear palsy (PSP) is a neurodegenerative disease with motor, cognitive, and behavioral symptomatology. Cholinergic dysfunction is thought to underpin several key symptoms. There is known pathologic involvement of the corticobasal ganglia-thalamocortical loops in PSP, but little attention has been focused on potential thalamic dysfunction. Using autoradiography, we measured muscarinic M2 and M4 receptors in specific thalamic nuclei involved in the limbic and motor loops in patients with PSP (n = 11) and compared results from brain tissue of subjects with Lewy body dementias (including dementia with Lewy bodies and Parkinson disease with dementia, n = 31), Alzheimer disease (n = 22) and normal elderly control subjects (n = 27). In the thalamus M2 receptors were more abundant than M4 receptors and were most densely concentrated in the anteroprincipal (AP) and mediodorsal (MD) nuclei, which connect to limbic cortices. M2 receptor binding was reduced in the AP nucleus in PSP compared with control subjects and those with Lewy body dementias. M4 receptors were markedly reduced in the MD nucleus in those with PSP compared with control subjects. M4 receptors were also reduced in the subthalamic nucleus in patients with PSP. M4 receptor binding was reduced in the MD nucleus in the Lewy body dementia and Alzheimer disease groups compared with control subjects. There were no significant changes in the ventrolateral nucleus (motor). Cholinergic dysfunction within the AP and MD nuclei of the thalamus may contribute to behavioral and cognitive disturbances associated with PSP.

Ingelsson M, Ramasamy K, Cantuti-Castelvetri I, Skoglund L, Matsui T, Orne J, Kowa H, Raju S, Vanderburg CR, Augustinack JC, de Silva R, Lees AJ, Lannfelt L, Growdon JH, Frosch MP, Standaert DG, Irizarry MC, Hyman BT. · Harvard Medical School, Massachusetts General Hospital, 114 16th Street, Charlestown, MA 02129, USA. · Acta Neuropathol. · Pubmed #16802167 No free full text.

Abstract: Defective splicing of tau mRNA, promoting a shift between tau isoforms with (4R tau) and without (3R tau) exon 10, is believed to be a pathological consequence of certain tau mutations causing frontotemporal dementia. By assessing protein and mRNA levels of 4R tau and 3R tau in 27 AD and 20 control temporal cortex, we investigated whether altered tau splicing is a feature also in Alzheimer's disease (AD). However, apart from an expected increase of sarcosyl-insoluble tau in AD, there were no significant differences between the groups. Next, by laser-capture microscopy and quantitative PCR, we separately analyzed CA1 hippocampal neurons with and without neurofibrillary pathology from six of the AD and seven of the control brains. No statistically significant differences in 4R tau/3R tau mRNA were found between the different subgroups. Moreover, we confirmed the absence of significant ratio differences in a second data set with laser-captured entorhinal cortex neurons from four AD and four control brains. Finally, the 4R tau/3R tau ratio in CA1 neurons was roughly half of the ratio in temporal cortex, indicating region-specific differences in tau mRNA splicing. In conclusion, this study indicated region-specific and possibly cell-type-specific tau splicing but did not lend any support to overt changes in alternative splicing of tau exon 10 being an underlying factor in AD pathogenesis.

Gandhi S, Muqit MM, Stanyer L, Healy DG, Abou-Sleiman PM, Hargreaves I, Heales S, Ganguly M, Parsons L, Lees AJ, Latchman DS, Holton JL, Wood NW, Revesz T. · Department of Molecular Neuroscience, Institute of Neurology University College London, London, UK. · Brain. · Pubmed #16702191 links to  free full text

Abstract: Parkinson's disease is a common incurable neurodegenerative disease whose molecular aetiology remains unclear. The identification of Mendelian genes causing rare familial forms of Parkinson's disease has revealed novel proteins and pathways that are likely to be relevant in the pathogenesis of sporadic Parkinson's disease. Recently, mutations in a novel gene, PINK1, encoding a 581 amino acid protein with both mitochondrial targeting and serine/threonine kinase domains, were identified as a cause of autosomal recessive parkinsonism. This provided important evidence for the role of the mitochondrial dysfunction and kinase pathways in neurodegeneration. In this study, we report the first characterization of the PINK1 protein in normal human and sporadic Parkinson's brains, in addition to Parkinson's cases with heterozygous PINK1 mutations. The possible role of the PINK1 protein was also assessed in a number of neurodegenerative diseases characterized by proteinaceous inclusions. For these studies, rabbit polyclonal antibodies were raised against two peptide sequences within the N-terminal hydrophilic loops of PINK1 protein. Using immunohistochemistry and western blotting we were able to demonstrate that PINK1 is a ubiquitous protein expressed throughout the human brain and it is found in all cell types showing a punctate cytoplasmic staining pattern consistent with mitochondrial localization. Fractionation studies of human and rat brain confirm that PINK1 is localized to the mitochondrial membranes. In addition, we show that PINK1 is detected in a proportion of Lewy bodies in cases of sporadic Parkinson's disease and Parkinson's disease associated with heterozygous mutations in the PINK1 gene, which are clinically and pathologically indistinguishable from the sporadic cases. PINK1 was absent in cortical Lewy bodies, in neurofibrillary tangles in Alzheimer's disease, progressive supranuclear palsy and corticobasal degeneration, and in the glial and neuronal alpha-synuclein positive inclusions in multiple system atrophy. These studies provide for the first time in vivo morphological and biochemical evidence to support a mitochondrial localization of PINK1 and underpin the significance of mitochondrial dysfunction in the pathogenesis of nigral cell degeneration in Parkinson's disease.

Myers AJ, Kaleem M, Marlowe L, Pittman AM, Lees AJ, Fung HC, Duckworth J, Leung D, Gibson A, Morris CM, de Silva R, Hardy J. · Laboratory of Neurogenetics, National Institute on Aging, National Institute of Health, Bethesda, MD 20892-3707, USA. · Hum Mol Genet. · Pubmed #16000317 links to  free full text

Abstract: Although it is clear that microtubule associated protein tau (MAPT) is involved in Alzheimer's disease (AD) pathology, it has not been clear whether it is involved genetically. We have recently examined the MAPT locus in progressive supranuclear palsy and found that a haplotype (H1c) on the background of the well-described H1 clade is associated with PSP. Here we report that the same haplotype is associated with the risk of AD in two autopsy confirmed series of cases with ages at death >65 years.

Morris HR, Steele JC, Crook R, Wavrant-De Vrièze F, Onstead-Cardinale L, Gwinn-Hardy K, Wood NW, Farrer M, Lees AJ, McGeer PL, Siddique T, Hardy J, Perez-Tur J. · Department of Molecular Pathogenesis and Sara Koe PSP Research Centre, Queen Square Brain Bank for Neurological Disorders, Insatitute of Neurology, University College London, London, England, UK. · Arch Neurol. · Pubmed #15596609 links to  free full text

Abstract: BACKGROUND: Parkinsonism-dementia complex (PDC) is a neurofibrillary tangle degeneration involving the deposition of Alzheimer-type tau, predominantly in the mesial temporal cortex, brainstem, and basal ganglia. It occurs in focal geographic isolates, including Guam and the Kii peninsula of Japan. The familial clustering of the disease has suggested that a genetic factor could be important in its etiology. OBJECTIVE: To determine whether a genetic locus could be identified, linked, or associated with PDC. DESIGN AND PATIENTS: We performed a genome-wide association study of 22 Guamanian PDC and 19 control subjects using 834 microsatellite markers with an approximate genome-wide marker density of 4.4 centimorgans. RESULTS: Two-point association analysis identified 17 markers (P<.015). Each of these markers then underwent conventional linkage analysis in 5 families with PDC. One marker, D20S103, generated a logarithm of odds score of greater than 1.5. Multipoint association analysis also highlighted 2 other areas on chromosome 14q (adjacent to D14S592, 59.2 megabases [M]) and chromosome 20 (adjacent to D20S470, 17.4 M) with multipoint association logarithm of the odds scores of greater than 2. The areas around D20S103, D14S592, and D20S470 were further analyzed by association using additional microsatellite markers and by conventional linkage analysis. This did not provide further evidence for the role of these areas in PDC. CONCLUSIONS: This study has not identified a single gene locus for PDC, confirming the impression of a geographic disease isolate with a complex genetic, a genetic/environmental etiology, or a purely environmental etiology.

Osaki Y, Ben-Shlomo Y, Lees AJ, Daniel SE, Colosimo C, Wenning G, Quinn N. · National Hospital for Neurology and Neurosurgery, London, United Kingdom. · Mov Disord. · Pubmed #14978673 No free full text.

Abstract: We assessed the accuracy of clinical diagnosis of progressive supranuclear palsy (PSP, Steele-Richardson-Olszewski disease) and the validity of existing sets of clinical diagnostic criteria for PSP (see Appendix) using neuropathologically examined cases from the Queen Square Brain Bank for Neurological Disorders. Diagnosis of PSP was made by 40 different physicians, and 60 cases clinically diagnosed as PSP when last assessed in life were studied. In 47 cases (78%), the diagnosis of PSP was confirmed pathologically. False-positive diagnoses included Parkinson's disease with significant additional cortical Lewy body (n = 3) or Alzheimer (n = 1) pathology, multiple system atrophy (n = 4), and corticobasal degeneration, Pick's disease, motor neurone disease, cerebrovascular disease, and a sporadic case of frontotemporal dementia and parkinsonism linked to chromosome 17 (1 case each). Most cases of PSP were diagnosed accurately by neurologists at the final assessment. Although application of National Institute of Neurological Disorders and the Society for PSP possible category marginally improved the accuracy of initial clinical diagnosis, none of the existing operational criteria could significantly improve accuracy of the final clinical diagnosis.

Gibb GM, de Silva R, Revesz T, Lees AJ, Anderton BH, Hanger DP. · Department of Neuroscience, Box PO 38, Institute of Psychiatry KCL, De Crespigny Park, London SE5 8AF, UK. · Brain Res Mol Brain Res. · Pubmed #14969740 No free full text.

Abstract: We found previously that aggregated insoluble tau protein in progressive supranuclear palsy (PSP) brains exhibits a heterogeneous pattern that is not segregated by the type of clinical presentation. Here we have investigated tau isoform composition from 20 PSP cases and found marked variation between different brains. Cases were classified into three groups, each comprising essentially of (1) 1N4R; (2) 1N4R and 1N3R; or (3) 1N4R, 1N3R and 0N4R tau isoforms. There was also an absence of a simple relationship between isoform composition and the pattern of insoluble tau before dephosphorylation. We conclude that there is distinct molecular heterogeneity in the involvement of tau isoforms in the tau pathology in PSP.

Perry EK, Kilford L, Lees AJ, Burn DJ, Perry RH. · MRC Building, Wolfson Research Centre, Newcastle General Hospital, Newcastle upon Tyne, United Kingdom. · Ann Neurol. · Pubmed #12891676 No free full text.

Abstract: The hypothesis that blockade of muscarinic receptors is associated with increased Alzheimer-type pathology was investigated in Parkinson's disease. Amyloid plaque densities were more than 2.5-fold higher in cases treated with antimuscarinic medication in the long term compared with untreated or short-term treated cases (p = 0.005 and 0.00005, respectively). Neurofibrillary tangle densities were also highest in chronic compared with untreated or acute-treated groups (p = 0.02 and 0.05, respectively). The findings, if replicated, have potential implications for the use of anticholinergic medication in elderly Parkinson's disease patients.

Hope AD, de Silva R, Fischer DF, Hol EM, van Leeuwen FW, Lees AJ. · Reta Lila Weston Institute of Neurological Studies, University College, London, UK. · J Neurochem. · Pubmed #12871580 No free full text.

Abstract: Intracellular protein inclusions in Alzheimer's disease and progressive supranuclear palsy contain UBB+1, a variant ubiquitin. UBB+1 is able block the 26S proteasome in cell lines. Proteasome inhibition by drug action has previously been shown to induce a heat-shock response and render protection against stress. We investigated UBB+1 by developing a stable, conditional expression model in SH-SY5Y human neuroblastoma cells. Induction of UBB+1 expression caused proteasome inhibition as was confirmed by reduced ability to process misfolded canavanyl proteins, accumulation of GFPu, a proteasome substrate, and reduced cleavage of a fluorogenic substrate. We show that expression of UBB+1 induces expression of heat-shock proteins. This priming of the chaperone system in these cells promotes a subsequent resistance to tert-butyl hydroperoxide-mediated oxidative stress. We conclude that although UBB+1-expressing cells have a compromised ubiquitin-proteasome system, they are protected against oxidative stress conditions.

Lees AJ. · Reta Lila Weston Institute for Neurological Disorders, Institute of Neurology, University College London, London, UK. · Mov Disord. · Pubmed #18175393 No free full text.

Abstract: James Parkinson's Essay on the Shaking Palsy published in 1817 provided the first clear clinical description for the disorder now known throughout the world by his name. His primary reason for publishing his monograph shortly before his retirement from medical practice was to draw the medical profession's attention to a malady, which had not yet been defined as a nosological entity. He also hoped that the eminent anatomists of the day would be stimulated to elucidate the pathological lesion responsible for the clinical picture and that this in turn might lead to a rational cure. The concept of Parkinson's disease remains clinically based and successive generations of neurologists have refined and embellished Parkinson's seminal descriptions. Narrative accounts by affected individuals have also helped physicians understand what it is like to live with Parkinson's disease. For many years, the pathological hallmarks of Parkinson's disease were disputed and there were few clinico-pathological reports with adequate clinical description. However, most neurologists now link severe loss of nigral cells in the ventrolateral tier of the pars compacta of the substantia nigra with bradykinesia and the presence of Lewy bodies in a number of discrete brain stem and cortical regions with Parkinson's disease. There are many unanswered clinical questions relating to Parkinson's disease including the striking heterogeneity and frequent limb asymmetry. It also remains somewhat uncertain whether Parkinson's disease is ever truly unilateral by the time of clinical presentation and whether the hand rather than the foot is the most common site of onset. Hyposmia and visual hallucinations are helpful pointers in distinguishing Parkinson's disease from atypical Parkinsonism and should be specifically enquired about in the history. Simple reliable cultural-specific smell identification batteries are an urgent need and target of clinical research. It remains to be determined whether Alzheimer type dementia as opposed to a dysexecutive syndrome should be considered a part of Parkinson's disease and further detailed clinico-pathological correlative studies are needed. It is also unclear whether autosomal dominant monogenetic Parkinsonism due to synuclein or LRRK-2 mutations will prove to be identical clinically with Parkinson's disease and for the present it is wiser to regard Parkinson's disease as a sporadic disorder. Parkinson was an active political reformer and if alive today would certainly be campaigning to translate more effectively the rich seam of neuroscientific research of the last decade into therapeutic benefits for the rising number of people who are developing the shaking palsy as a result of increasing longevity in the developed world.

Schott JM, Lees AJ, Rossor MN. · No affiliation provided · Ann Neurol. · Pubmed #15455442 No free full text.

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