Publications by authors named "Evelyn Jaros"

34 Publications

Clinicians' ability to diagnose dementia with Lewy bodies is not affected by β-amyloid load.

Neurology 2015 Feb 31;84(5):496-9. Epub 2014 Dec 31.

From the Division of Neurology V and Neuropathology (P.T.), IRCCS Foundation, Carlo Besta Neurologic Institute, Milan, Italy; Institute for Aging and Health (J.A., A.T., A.B., E.J., D.J.L., R.H.P., L.R., L.W., I.G.M.), Wolfson Research Center, Campus for Aging and Vitality, Newcastle University, Newcastle upon Tyne, UK; and Division of Neurology and Neurophysiology (M.O.), Azienda Ospedaliera di Busto Arsizio, Presidio di Tradate, Italy.

Objective: To investigate whether an increasing load of β-amyloid and/or neuritic plaques influences the phenotype, and thus the clinical diagnostic accuracy, of dementia with Lewy bodies (DLB).

Methods: A series of 64 subjects with autopsy-proven DLB was studied. Last diagnosis before death was used to determine the clinical diagnostic accuracy of DLB in relation to Lewy body distribution and extent of Alzheimer β-amyloid and/or neuritic pathology. DLB pathologic diagnosis was made according to consensus criteria, using α-synuclein immunostaining for Lewy body identification. β-Amyloid immunostaining was used for quantifying β-amyloid deposits. The Consortium to Establish a Registry for Alzheimer's Disease criteria and Braak stage were applied for semiquantitative grading of neuritic plaque and neurofibrillary tangle pathology.

Results: Overall clinical diagnostic accuracy for the entire DLB cohort was high (80%), reflecting the high prevalence of core clinical features (fluctuations [81%], parkinsonism [77%], visual hallucinations [70%]). Lower frequencies of core clinical features of DLB, resulting in lower accuracy of its clinical diagnosis, were associated with decreasing Lewy body distribution (p < 0.0001) and with increasing neuritic plaque pathology (p = 0.035), but not with the number of β-amyloid plaque deposits.

Conclusions: The likelihood of occurrence of the DLB clinical syndrome is positively related to the extent of Lewy body pathology and negatively related to the severity of Alzheimer neuritic pathology, while β-amyloid load has no effect.
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http://dx.doi.org/10.1212/WNL.0000000000001204DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4336072PMC
February 2015

Accumulation of dipeptide repeat proteins predates that of TDP-43 in frontotemporal lobar degeneration associated with hexanucleotide repeat expansions in C9ORF72 gene.

Neuropathol Appl Neurobiol 2015 Aug 30;41(5):601-12. Epub 2015 Apr 30.

Institute of Brain, Behaviour and Mental Health, University of Manchester, Salford Royal Hospital, Salford, UK.

Aims: Frontotemporal lobar degeneration (FTLD) and motor neurone disease are linked by the possession of a hexanucleotide repeat expansion in C9ORF72, and both show neuronal cytoplasmic inclusions within cerebellar and hippocampal neurones which are TDP-43 negative but immunoreactive for p62 and dipeptide repeat proteins (DPR), these being generated by a non-ATG RAN translation of the expanded region of the gene.

Methods: Twenty-two cases of FTLD from Newcastle were analysed for an expansion in C9ORF72 by repeat primed PCR and Southern blot. Detailed case note analysis was performed, and blinded retrospective clinical impressions were achieved by review of clinical histories. Sections from all major brain regions were immunostained for TDP-43, p62 and DPR. The extent of TDP-43 and DPR pathology in expansion bearers was compared with that in 13 other previously identified cases from the Manchester Brain Bank with established disease.

Results: Three Newcastle patients bearing an expansion in C9ORF72 were identified. These three patients died prematurely, two from bronchopneumonia within 10 months and 3 years of onset, and one from myocardial infarction 3 years after onset. In all three, DPR were plentiful throughout all cerebral cortical regions, hippocampus and cerebellum, but TDP-43 pathological changes were sparse. The severity of DPR pathological changes in these three patients was similar to that in the Manchester series, although the extent of TDP-43 pathology was significantly less.

Conclusion: Widespread accumulation of DPR within nerve cells may occur much earlier than that of TDP-43 in patients with FTLD bearing expansion in C9ORF72.
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http://dx.doi.org/10.1111/nan.12178DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4934135PMC
August 2015

Frontotemporal dementia and its subtypes: a genome-wide association study.

Lancet Neurol 2014 Jul;13(7):686-99

University of Milan, Milan, Italy; Fondazione Cà Granda, IRCCS Ospedale Maggiore Policlinico, Milan, Italy.

Background: Frontotemporal dementia (FTD) is a complex disorder characterised by a broad range of clinical manifestations, differential pathological signatures, and genetic variability. Mutations in three genes-MAPT, GRN, and C9orf72--have been associated with FTD. We sought to identify novel genetic risk loci associated with the disorder.

Methods: We did a two-stage genome-wide association study on clinical FTD, analysing samples from 3526 patients with FTD and 9402 healthy controls. To reduce genetic heterogeneity, all participants were of European ancestry. In the discovery phase (samples from 2154 patients with FTD and 4308 controls), we did separate association analyses for each FTD subtype (behavioural variant FTD, semantic dementia, progressive non-fluent aphasia, and FTD overlapping with motor neuron disease [FTD-MND]), followed by a meta-analysis of the entire dataset. We carried forward replication of the novel suggestive loci in an independent sample series (samples from 1372 patients and 5094 controls) and then did joint phase and brain expression and methylation quantitative trait loci analyses for the associated (p<5 × 10(-8)) single-nucleotide polymorphisms.

Findings: We identified novel associations exceeding the genome-wide significance threshold (p<5 × 10(-8)). Combined (joint) analyses of discovery and replication phases showed genome-wide significant association at 6p21.3, HLA locus (immune system), for rs9268877 (p=1·05 × 10(-8); odds ratio=1·204 [95% CI 1·11-1·30]), rs9268856 (p=5·51 × 10(-9); 0·809 [0·76-0·86]) and rs1980493 (p value=1·57 × 10(-8), 0·775 [0·69-0·86]) in the entire cohort. We also identified a potential novel locus at 11q14, encompassing RAB38/CTSC (the transcripts of which are related to lysosomal biology), for the behavioural FTD subtype for which joint analyses showed suggestive association for rs302668 (p=2·44 × 10(-7); 0·814 [0·71-0·92]). Analysis of expression and methylation quantitative trait loci data suggested that these loci might affect expression and methylation in cis.

Interpretation: Our findings suggest that immune system processes (link to 6p21.3) and possibly lysosomal and autophagy pathways (link to 11q14) are potentially involved in FTD. Our findings need to be replicated to better define the association of the newly identified loci with disease and to shed light on the pathomechanisms contributing to FTD.

Funding: The National Institute of Neurological Disorders and Stroke and National Institute on Aging, the Wellcome/MRC Centre on Parkinson's disease, Alzheimer's Research UK, and Texas Tech University Health Sciences Center.
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http://dx.doi.org/10.1016/S1474-4422(14)70065-1DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4112126PMC
July 2014

Anti-GQ1b ganglioside positive Miller Fisher syndrome - evidence of paranodal pathology on nerve biopsy.

J Neuromuscul Dis 2014;1(2):191-195

Glasgow Biomedical Research Centre, College of Medical, Veterinary and Life Science, Institute of Infection, Immunity and Inflammation, University of Glasgow, Glasgow, UK.

Background: Miller Fisher syndrome is a regional variant of Guillain-Barre syndrome with a characteristic clinical triad of ophthalmoplegia, areflexia and ataxia and occasionally distal limb sensory loss. 90% of patients have associated antibodies to the GQ1b ganglioside. The pathophysiology of antibody-mediated peripheral nerve impairment remains uncertain. This report includes the first description of a peripheral sensory nerve biopsy in Miller Fisher syndrome.

Results: A single case report is described of a 46 year old woman who presented with 2 weeks of distal glove and stocking sensory loss to both deep and superficial sensory modalities, areflexia and weight loss. This was followed by rapid onset of ataxia, ophthalmoplegia, and bulbar impairment. Peripheral neurophysiology showed reduced sensory nerve amplitudes with preserved conduction velocities in keeping with an axonal pattern of impairment. Clinical concerns of a systemic inflammatory disorder led to a diagnostic peripheral nerve biopsy from the sensory branch of the radial nerve. However she subsequently made a complete recovery over 5 weeks. Combinatorial glycoarrays confirmed restricted serum binding for GQ1b in acute serum which later resolved in a convalescent sample. The nerve biopsy showed lengthening of nodes of Ranvier, myelin splitting and macrophage internodal axonal invasion without any features of demyelination.

Conclusions: The pathological features were strikingly similar to those found in acute motor axonal neuropathy and indicate the region of the node of Ranvier to be a primary focus of GQ1b induced damage in Miller Fisher syndrome, at least in this particular overlap syndrome with prominent sensory nerve involvement.
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January 2014

The impact of pathogenic mitochondrial DNA mutations on substantia nigra neurons.

J Neurosci 2013 Jun;33(26):10790-801

Newcastle University Centre for Brain Ageing and Vitality, Institute for Ageing and Health, and Wellcome Trust Centre for Mitochondrial Research, Institute for Ageing and Health, Newcastle University, Newcastle upon Tyne NE2 4HH, United Kingdom.

Mitochondrial defects within substantia nigra (SN) neurons are implicated in the pathogenesis of Parkinson's disease. SN neurons show increased mitochondrial defects, mitochondrial DNA deletion levels, and susceptibility to such dysfunction, although the role of mitochondria in neuronal degeneration remains uncertain. In this study, we addressed this important question by exploring changes within the mitochondria of SN neurons from patients with primary mitochondrial diseases to determine whether mitochondrial dysfunction leads directly to neuronal cell loss. We counted the pigmented neurons and quantified mitochondrial respiratory activity, deficiencies in mitochondrial proteins, and the percentage of pathogenic mutations in single neurons. We found evidence of defects of both complex I and complex IV of the respiratory chain in all patients. We found that marked neuronal cell loss was only observed in a few patients with mitochondrial disease and that all these patients had mutations in polymerase gamma (POLG), which leads to the formation of multiple mitochondrial DNA deletions over time, similar to aging and Parkinson's disease. Interestingly, we detected α-synuclein pathology in two mitochondrial patients with POLG mutations. Our observations highlight the complex relationship between mitochondrial dysfunction and the susceptibility of SN neurons to degeneration and α-synuclein pathology. Our finding that the loss of SN neurons was only severe in patients with POLG mutations suggests that acquired mitochondrial defects may be less well tolerated by SN neurons than by inherited ones.
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http://dx.doi.org/10.1523/JNEUROSCI.3525-12.2013DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6618501PMC
June 2013

Early-onset cataracts, spastic paraparesis, and ataxia caused by a novel mitochondrial tRNAGlu (MT-TE) gene mutation causing severe complex I deficiency: a clinical, molecular, and neuropathologic study.

J Neuropathol Exp Neurol 2013 Feb;72(2):164-75

Wellcome Trust Centre for Mitochondrial Research, Institute for Ageing and Health, The Medical School, Newcastle University, Newcastle upon Tyne, UK.

Mitochondrial respiratory chain disease is associated with a spectrum of clinical presentations and considerable genetic heterogeneity. Here we report molecular genetic and neuropathologic findings from an adult with an unusual manifestation of mitochondrial DNA disease. Clinical features included early-onset cataracts, ataxia, and progressive paraparesis, with sequencing revealing the presence of a novel de novo m.14685G>A mitochondrial tRNA(Glu) (MT-TE) gene mutation. Muscle biopsy showed that 13% and 34% of muscle fibers lacked cytochrome c oxidase activity and complex I subunit expression, respectively. Biochemical studies confirmed a marked decrease in complex I activity. Neuropathologic investigation revealed a large cystic lesion affecting the left putamen, caudate nucleus, and internal capsule, with evidence of marked microvacuolation, neuron loss, perivascular lacunae, and blood vessel mineralization. The internal capsule showed focal axonal loss, whereas brainstem and spinal cord showed descending anterograde degeneration in medullary pyramids and corticospinal tracts. In agreement with muscle biopsy findings, reduced complex I immunoreactivity was detected in the remaining neuronal populations, particularly in the basal ganglia and cerebellum, correlating with the neurologic dysfunction exhibited by the patient. This study emphasizes the importance of molecular genetic and postmortem neuropathologic analyses for furthering our understanding of underlying mechanisms of mitochondrial disorders.
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http://dx.doi.org/10.1097/NEN.0b013e31828129c5DOI Listing
February 2013

Synaptic proteins and choline acetyltransferase loss in visual cortex in dementia with Lewy bodies.

J Neuropathol Exp Neurol 2013 Jan;72(1):53-60

Institute for Ageing and Health, Wolfson Research Centre, Campus for Ageing and Vitality, Newcastle University, Newcastle upon Tyne, UK.

Functional neuroimaging studies have consistently reported abnormalities in the visual cortex in patients with dementia with Lewy bodies (DLB), but their neuropathologic substrates are poorly understood. We analyzed synaptic proteins and choline acetyltransferase (ChAT) in the primary (BA17) and association (BAs18/19) visual cortex in DLB and similar aged control and Alzheimer disease (AD) subjects. We found lower levels of synaptophysin, syntaxin, SNAP-25, and γ-synuclein in DLB subjects versus both aged control (68%-78% and 27%-72% for BA17 and BAs18/19, respectively) and AD cases (54%-67% and 10%-56% for BA17 and BAs18/19, respectively). The loss in ChAT activity in DLB cases was also greater in BA17 (72% and 87% vs AD and control values, respectively) than in BAs18/19 (52% and 65% vs AD and control groups, respectively). The observed synaptic and ChAT changes in the visual cortices were not associated with tau or β-amyloid pathology in the occipital or the frontal, temporal, and parietal neocortex. However, the neocortical densities of LBs, particular those in BA17 and BAs18/19, correlated with lower synaptic and ChAT levels in these brain areas. These findings draw attention to molecular changes within the primary visual cortex in DLB and correlate with the neuroimaging findings within the occipital lobe in patients with this disorder.
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http://dx.doi.org/10.1097/NEN.0b013e31827c5710DOI Listing
January 2013

Microangiopathy in the cerebellum of patients with mitochondrial DNA disease.

Brain 2012 Jun 9;135(Pt 6):1736-50. Epub 2012 May 9.

The Wellcome Trust Centre for Mitochondrial Research, Institute for Ageing and Health, Newcastle University, Newcastle upon Tyne, NE2 4HH, UK.

Neuropathological findings in mitochondrial DNA disease vary and are often dependent on the type of mitochondrial DNA defect. Many reports document neuronal cell loss, demyelination, gliosis and necrotic lesions in post-mortem material. However, previous studies highlight vascular abnormalities in patients harbouring mitochondrial DNA defects, particularly in those with the m.3243A>G mutation in whom stroke-like events are part of the mitochondrial encephalopathy lactic acidosis and stroke-like episodes syndrome. We investigated microangiopathic changes in the cerebellum of 16 genetically and clinically well-defined patients. Respiratory chain deficiency, high levels of mutated mitochondrial DNA and increased mitochondrial mass were present within the smooth muscle cells and endothelial cells comprising the vessel wall in patients. These changes were not limited to those harbouring the m.3243A>G mutation frequently associated with mitochondrial encephalopathy, lactic acidosis and stroke-like episodes, but were documented in patients harbouring m.8344A>G and autosomal recessive polymerase (DNA directed), gamma (POLG) mutations. In 8 of the 16 patients, multiple ischaemic-like lesions occurred in the cerebellar cortex suggestive of vascular smooth muscle cell dysfunction. Indeed, changes in vascular smooth muscle and endothelium distribution and cell size are indicative of vascular cell loss. We found evidence of blood-brain barrier breakdown characterized by plasma protein extravasation following fibrinogen and IgG immunohistochemistry. Reduced immunofluorescence was also observed using markers for endothelial tight junctions providing further evidence in support of blood-brain barrier breakdown. Understanding the structural and functional changes occurring in central nervous system microvessels in patients harbouring mitochondrial DNA defects will provide an important insight into mechanisms of neurodegeneration in mitochondrial DNA disease. Since therapeutic strategies targeting the central nervous system are limited, modulating vascular function presents an exciting opportunity to lessen the burden of disease in these patients.
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http://dx.doi.org/10.1093/brain/aws110DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3359757PMC
June 2012

Frontotemporal dementia in elderly individuals.

Arch Neurol 2012 Aug;69(8):1052-60

Department of Neuropathology, Walton Centre for Neurology and Neurosurgery, Liverpool, England, UK.

Objective: To determine whether cases of frontotemporal lobar degeneration (FTLD) do exist in elderly individuals and have clinical and neuropathological features distinct from those with presenile onset.

Design: Retrospective matched cohort study.

Setting: Regional Neuroscience Centre, North East England.

Patients: We compared clinicopathological features of 11 cases of FTLD in elderly individuals with 19 cases of presenile-onset FTLD.

Results: Retrospective case note analysis showed that most elderly patients with FTLD had behavioral features consistent with orbitofrontal and basofrontal involvement, similar to presenile-onset FTLD, though symptomatic memory loss was present in 91% (10 of 11) of elderly patients with FTLD compared with only 36% (7 of 19) of patients with presenile-onset FTLD. Neuropathologically, the group of elderly patients with FTLD comprised 7 with FTLD–TDP-43, 1 with ubiquitin-positive FTLD, 2 with FTLD-tau/Pick disease, and 1 with FTLD-tau/neurofibrillary tangle–predominant dementia with TDP-43, a composition similar to presenile-onset FTLD. However, hippocampal sclerosis was more common in elderly patients with FTLD than patients with presenile-onset FTLD (82% vs 37%) and more severe in elderly patients with FTLD (P < .05). By contrast, severe atrophy of the frontal and temporal lobes was less common in elderly patients with FTLD (frontal: 45%; temporal: 27%) than patients with presenile-onset FTLD (frontal: 63%; temporal: 78%). Elderly patients with FTLD represented 3.2% of all elderly patients with dementia autopsied at Newcastle General Hospital.

Conclusions: Frontotemporal lobar degeneration in elderly patients does exist as a separate entity from presenile-onset FTLD. Its main features include (1) clinically frequent memory loss and behavioral change predominating over language and semantic dysfunction and (2) neuropathologically prominent hippocampal sclerosis but less pronounced cortical lobar atrophy. Clinically, FTLD in elderly patients is underrecognized and should be considered in the elderly subjects presenting with an “atypical Alzheimer disease” phenotype.
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http://dx.doi.org/10.1001/archneurol.2011.3323DOI Listing
August 2012

Loss of myelin-associated glycoprotein in kearns-sayre syndrome.

Arch Neurol 2012 Apr;69(4):490-9

Mitochondrial Research Group, Institute for Aging and Health, Newcastle University, Framlington Place, Newcastle upon Tyne, United Kingdom.

Objective: To explore myelin components and mitochondrial changes within the central nervous system in patients with well-characterized mitochondrial disorders due to nuclear DNA or mitochondrial DNA (mtDNA) mutations.

Design: Immunohistochemical analysis, histochemical analysis, mtDNA sequencing, and real-time and long-range polymerase chain reaction were used to determine the pathogenicity of mtDNA deletions.

Setting: Department of Clinical Pathology, Columbia University Medical Center, and Newcastle Brain Tissue Resource.

Patients: Seventeen patients with mitochondrial disorders and 7 controls were studied from August 1, 2009, to August 1, 2010.

Main Outcome Measure: Regions of myelin-associated glycoprotein (MAG) loss.

Results: Myelin-associated glycoprotein loss in Kearns-Sayre syndrome was associated with oligodendrocyte loss and nuclear translocation of apoptosis-inducing factor, whereas inflammation, neuronal loss, and axonal injury were minimal. In a Kearns-Sayre syndrome MAG loss region, high levels of mtDNA deletions together with cytochrome- c oxidase-deficient cells and loss of mitochondrial respiratory chain subunits (more prominent in the white than gray matter and glia than axons) confirmed the pathogenicity of mtDNA deletions.

Conclusion: Primary mitochondrial respiratory chain defects affecting the white matter, and unrelated to inflammation, are associated with MAG loss and central nervous system demyelination.
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http://dx.doi.org/10.1001/archneurol.2011.2167DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3672633PMC
April 2012

Relationship between mitochondria and α-synuclein: a study of single substantia nigra neurons.

Arch Neurol 2012 Mar;69(3):385-93

Mitochondrial Research Group, Institute of Ageing and Health, The Medical School, Newcastle University, Newcastle upon Tyne, England.

Objective: To explore the relationship between α-synuclein pathology and mitochondrial respiratory chain protein levels within single substantia nigra neurons.

Design: We examined α-synuclein and mitochondrial protein expression in substantia nigra neurons of 8 patients with dementia with Lewy bodies, 5 patients with Parkinson disease, and 8 control subjects. Protein expression was determined using immunocytochemistry followed by densometric analysis.

Patients: We examined single substantia nigra neurons from 5 patients with idiopathic Parkinson disease (mean age, 81.2 years), 8 patients with dementia with Lewy bodies (mean age, 75 years), and 8 neurologically and pathologically normal control subjects (mean age, 74.5 years). The control cases showed minimal Lewy body pathology and cell loss. Patients with dementia with Lewy bodies and idiopathic Parkinson disease fulfilled the clinical and neuropathologic criteria for these diseases.

Results: Our results showed that mitochondrial density is the same in nigral neurons with and without α-synuclein pathology. However, there are significantly higher levels of the respiratory chain subunits in neurons containing α-synuclein pathology.

Conclusions: The finding of increased levels of respiratory chain complex subunits within neurons containing α-synuclein does not support a direct association between mitochondrial respiratory chain dysfunction and the formation of α-synuclein pathology.
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http://dx.doi.org/10.1001/archneurol.2011.2675DOI Listing
March 2012

Cerebellar ataxia in patients with mitochondrial DNA disease: a molecular clinicopathological study.

J Neuropathol Exp Neurol 2012 Feb;71(2):148-61

Mitochondrial Research Group, Institute for Ageing and Health, Newcastle University, Newcastle upon Tyne, United Kingdom.

Cerebellar ataxia is a prominent clinical symptom in patients with mitochondrial DNA (mtDNA) disease. This is often progressive with onset in young adulthood. We performed a detailed neuropathologic investigation of the olivary-cerebellum in 14 genetically and clinically well-defined patients with mtDNA disease. Quantitative neuropathologic investigation showed varying levels of loss of Purkinje cells and neurons of the dentate nucleus and inferior olivary nuclei. Typically, focal Purkinje cell loss was present in patients with the m.3243A>G mutation caused by the presence of microinfarcts, with relative preservation of neuronal cell populations in the olivary and dentate nuclei. In contrast, patients with the m.8344A>G mutation or recessive POLG mutations showed extensive and global neuronal cell loss in all 3 olivary-cerebellum areas examined. Molecular analysis of mutated mtDNA heteroplasmy levels revealed that neuronal cell loss occurred independently of the level of mutated mtDNA present within surviving neurons. High levels of neuronal respiratory chain deficiency, particularly of complex I, were detected in surviving cells; levels of deficiency were greater in regions with extensive cell loss. We found a relationship between respiratory deficiency and neuronal cell density, indicating that neuronal cell death correlates with respiratory deficiency. These findings highlight the vulnerability of the olivary-cerebellum to mtDNA defects.
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http://dx.doi.org/10.1097/NEN.0b013e318244477dDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3272439PMC
February 2012

Sensory neuronopathy in patients harbouring recessive polymerase γ mutations.

Brain 2012 Jan 20;135(Pt 1):62-71. Epub 2011 Dec 20.

Mitochondrial Research Group, Institute for Ageing and Health, Newcastle University, Framlington Place, Newcastle upon Tyne, NE2 4HH, UK.

Defects in the mitochondrial DNA replication enzyme, polymerase γ, are an important cause of mitochondrial disease with ∼25% of all adult diagnoses attributed to mutations in the POLG gene. Peripheral neuronopathy is often part of the clinical syndrome and can represent the most disabling feature. In spite of this, the molecular mechanisms underlying the neuronopathy remain to be elucidated and treatment strategies are limited. In the present study, we use a combined approach comprising clinical, electrophysiological, neuropathological and molecular genetic investigations to unravel the mechanisms underpinning peripheral neuronopathy in autosomal recessive polymerase γ-related disease. Electrophysiological assessments documented a dorsal root ganglionopathy in all 11 cases. Of the 11 cases, eight also showed changes consistent with motor fibre loss. Detailed neuropathological investigation of two patients confirmed the electrophysiological findings, revealing atrophy of posterior columns and striking neuronal cell loss from the dorsal root ganglia, which was accompanied by severe mitochondrial biochemical abnormalities involving respiratory chain complexes I and IV due to clonally-expanded mitochondrial DNA deletions and a significant reduction in mitochondrial DNA copy number in affected neurons. We propose that the respiratory chain defects, secondary to mitochondrial DNA deletion and depletion, are likely to be responsible for pathology observed in the dorsal root ganglion and the sensory ganglionopathy documented electrophysiologically.
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http://dx.doi.org/10.1093/brain/awr326DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3267986PMC
January 2012

Mitochondrial DNA deletions cause the biochemical defect observed in Alzheimer's disease.

Neurobiol Aging 2012 Sep 16;33(9):2210-4. Epub 2011 Sep 16.

Centre for Brain Ageing and Vitality, Institute for Ageing and Health, Newcastle University, Newcastle upon Tyne, UK.

Alzheimer's disease (AD) is the most common form of dementia, increasing in prevalence with age. Most patients who develop AD have an unknown cause, but characteristic neuropathological features include the deposition of extracellular amyloid beta and of intraneuronal hyperphosphorylated tau protein. Researchers have previously implicated mitochondrial dysfunction in AD. We previously showed an increase in neurons displaying a mitochondrial biochemical defect-cytochrome-c oxidase (COX) deficiency-in the hippocampus in patients with sporadic AD compared with age-matched controls. COX deficiency is well described as a marker of mitochondrial (mt) DNA dysfunction. This present study analyzed the mtDNA in single neurons from both COX normal and COX-deficient cells. Analysis of the mtDNA revealed that COX deficiency is caused by high levels of mtDNA deletions which accumulate with age. Future research is needed to clarify the role mtDNA deletions have in normal aging and investigate the relationship between mtDNA deletions and the pathogenesis of sporadic AD.
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http://dx.doi.org/10.1016/j.neurobiolaging.2011.08.009DOI Listing
September 2012

Expression analysis of dopaminergic neurons in Parkinson's disease and aging links transcriptional dysregulation of energy metabolism to cell death.

Acta Neuropathol 2011 Jul 4;122(1):75-86. Epub 2011 May 4.

Department of Neurology with Friedrich-Baur-Institute, Klinikum Großhadern, Ludwig-Maximilians-University, Marchioninistr. 15, 81377 Munich, Germany.

Dopaminergic (DA) neuron degeneration is a feature of brain aging but is markedly increased in patients with Parkinson's disease (PD). Recent data indicate elevated metabolic stress as a possible explanation for DA neuron vulnerability. Using laser capture microdissection, we isolated DA neurons from the substantia nigra pars compacta of PD patients, age-matched and young controls to determine transcriptional changes by expression profiling and pathway analysis. We verified our findings by comparison to a published dataset. Parallel processing of isolated neurons and bulk tissue allowed the discrimination of neuronal and glial transcription signals. Our data show that genes known to be involved in neural plasticity, axon and synaptic function, as well as cell fate are differentially regulated in aging DA neurons. The transcription patterns in aging suggest a largely maintained expression of genes in energy-related pathways in surviving neurons, possibly supported by the mediation of PPAR/RAR and CREB signaling. In contrast, a profound down-regulation of genes coding for mitochondrial and ubiquitin--proteasome system proteins was seen in PD when compared to the age-matched controls. This is in accordance with the established mitochondrial dysfunction in PD and provides evidence for mitochondrial impairment at the transcriptional level. In addition, the PD neurons had disrupted pathways that comprise a network involved in the control of energy metabolism and cell survival in response to growth factors, oxidative stress, and nutrient deprivation (PI3K/Akt, mTOR, eIF4/p70S6K and Hif-1α). PI3K/Akt and mTOR signaling are central hubs of this network which is of relevance to longevity and--together with induction of mitochondrial biogenesis--may constitute potential targets for therapeutic intervention.
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http://dx.doi.org/10.1007/s00401-011-0828-9DOI Listing
July 2011

The most common type of FTLD-FUS (aFTLD-U) is associated with a distinct clinical form of frontotemporal dementia but is not related to mutations in the FUS gene.

Acta Neuropathol 2011 Jul 20;122(1):99-110. Epub 2011 Mar 20.

Mental Health and Neurodegeneration Research Group, Faculty of Human and Medical Sciences, University of Manchester, Manchester, UK.

Frontotemporal lobar degeneration (FTLD) is clinically, pathologically and genetically heterogeneous. Recent descriptions of a pathological sub-type that is ubiquitin positive, TDP-43 negative and immunostains positive for the Fused in Sarcoma protein (FUS) raises the question whether it is associated with a distinct clinical phenotype identifiable on clinical grounds, and whether mutations in the Fused in Sarcoma gene (FUS) might also be associated with FTLD. Examination of a pathological series of 118 cases of FTLD from two centres, showing tau-negative, ubiquitin-positive pathology, revealed FUS pathology in five patients, four classified as atypical FTLD with ubiquitin inclusions (aFTLD-U), and one as neuronal intermediate filament inclusion disease (NIFID). The aFTLD-U cases had youthful onset (22-46 years), an absence of strong family history, a behavioural syndrome consistent with frontotemporal dementia (FTD) and severe caudate atrophy. Their cognitive/behavioural profile was distinct, characterised by prominent obsessionality, repetitive behaviours and rituals, social withdrawal and lack of engagement, hyperorality with pica, and marked stimulus-bound behaviour including utilisation behaviour. They conformed to the rare behavioural sub-type of FTD identified previously by us as the "stereotypic" form, and linked to striatal pathology. Cognitive evaluation revealed executive deficits in keeping with subcortical-frontal dysfunction, but no cortical deficits in language, perceptuospatial skills or praxis. The patient with NIFID was older and exhibited aphasia and dyspraxia. No patient had clinical evidence of motor neurone disease during life, or a mutation in the FUS gene. In the complementary clinical study of 312 patients with clinical syndromes of FTLD, genetic analysis revealed a 6 bp deletion in FUS in 3 patients, of questionable significance. One presented a prototypical picture of FTD, another expressive language disorder, and the third semantic dementia. None showed the early onset age or distinctive 'stereotypic' picture of patients with aFTLD-U. We conclude that aFTLD-U is associated with a distinct clinical form of frontotemporal dementia, potentially allowing identification of such patients in life with a high degree of precision. Whether mutations in the FUS gene cause some cases of FTLD remains unresolved.
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http://dx.doi.org/10.1007/s00401-011-0816-0DOI Listing
July 2011

Neuropathological correlates of volumetric MRI in autopsy-confirmed Lewy body dementia.

Neurobiol Aging 2012 Jul 24;33(7):1228-36. Epub 2011 Feb 24.

Institute for Ageing and Health, Newcastle University, Campus for Ageing and Vitality, Newcastle upon Tyne, UK.

The objective of this study was to determine the neuropathological correlates of regional medial temporal lobe volume measures on magnetic resonance imaging (MRI) in subjects with Lewy body dementia (LBD). Twenty-three autopsy-confirmed LBD cases with an MRI scan close to death (mean 1.5 years) were studied. MRI-based volumetric measures were calculated for total intracranial volume, hippocampus, entorhinal cortex, and amygdala. Quantitative neuropathological analysis of plaques, tangles, and Lewy bodies were carried out in the same regions. Spearman's rho was used to examine correlations between MRI volumes and neuropathology measures and linear regression to assess the relationship between neuropathology and MRI volumes. A significant inverse correlation was observed between normalized amygdala volume and percent area of Lewy bodies in the amygdala (r = -0.461, p = 0.035). There were no other significant correlations between regional MRI volume and measures of neuropathology. Lewy body, but not Alzheimer's disease (AD) pathology was associated with reduced amygdala volume in pathologically-verified LBD cases but neither Lewy body nor Alzheimer's disease pathology was associated with volume loss in the hippocampus or entorhinal cortex, suggesting other neuropathological factors account for atrophy in these structures in LBD.
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http://dx.doi.org/10.1016/j.neurobiolaging.2010.12.015DOI Listing
July 2012

Pathological correlates of frontotemporal lobar degeneration in the elderly.

Acta Neuropathol 2011 Mar 27;121(3):365-71. Epub 2010 Oct 27.

Department of Neuropathology, Walton Centre for Neurology and Neurosurgery, Lower Lane, Liverpool, UK.

Frontotemporal lobar degeneration (FTLD) is generally recognised as a disorder with presenile onset (that is before 65 years of age) with only occasional cases presenting later than this. We set out to determine what proportion of cases of FTLD had late onset of disease and whether such cases of FTLD had distinctive clinical and neuropathological features as compared to cases with presenile onset. Within a combined Manchester and Newcastle autopsy series of 117 cases with pathologically confirmed FTLD (109/117 cases also met Lund Manchester clinical criteria for FTLD), we identified 30 cases (onset age range 65-86 years), comprising 25% of all FTLD cases ascertained in these two centres over a 25-year period. Neuropathologically, the 30 elderly cases presented features of several FTLD histological subgroups [FTLD-TDP (types 1, 2 and 3, 19 cases (63%)], FLTD-tau [MAPT, PiD and CBD, 10 cases (33%)] and FTLD-UPS (1 case), similar in range of phenotypes to that seen in the presenile group, though patients with MAPT, but not PGRN, mutation, or FUS pathology, were notably absent or fewer in the elderly group. Hippocampal sclerosis (HS) was present in 13/30 of the elderly FTLD cases (43%) compared with 14/79 (18%) (P = 0.012) in the presenile FTLD patients. Lobar atrophy present in most of the younger patients was prominent in only 25% of the elderly subjects. Prospective and retrospective psychiatric and medical case note analysis showed that the majority of the elderly FTLD patients, like their younger counterparts, had behavioural features consistent with frontotemporal dementia. FTLD is common amongst elderly persons and all or most of the major clinical and histological subtypes present in younger individuals can be seen in the older group.
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http://dx.doi.org/10.1007/s00401-010-0765-zDOI Listing
March 2011

Selective loss of dopamine D2 receptors in temporal cortex in dementia with Lewy bodies, association with cognitive decline.

Synapse 2007 Nov;61(11):903-11

Institute for Ageing and Health, Wolfson Research Centre, Newcastle General Hospital, Newcastle-upon-Tyne NE4 6BE, United Kingdom.

Dementia with Lewy bodies (DLB) is a progressive dementia frequently accompanied by psychotic symptoms. Similar symptoms can occur in Alzheimer's disease (AD) to a lesser extent. The use of neuroleptic medication to treat psychosis in both diseases is of modest efficacy and can induce severe adverse reactions in DLB. Dopamine D2 receptors in the cerebral cortex are the putative target for the antipsychotic action of these drugs, but the status of these receptors in DLB is unknown. Autoradiography was used to examine the density D2 receptors in postmortem temporal cortex tissue from prospectively assessed patients with neuropathologically confirmed DLB and AD. D2 receptors were substantially (over 40%) and significantly (P < 0.001) reduced in temporal cortex in DLB, and in DLB with concomitant Alzheimer pathology, but was not significantly changed in AD. This reduction correlated with greater cognitive decline (P < 0.01), but was not significantly related to visual or auditory hallucinations or delusions. D2 receptor density was inversely correlated with cortical Lewy body pathology in the neocortex (P < 0.001). The specific loss of D2 receptors associated with Lewy body pathology, in conjunction with our previous finding of low D2 receptors in striatum in DLB, provides a possible explanation for neuroleptic intolerance. That the reduction of D2 receptors correlated with cognitive decline suggests that neuroleptics, as dopamine D2 receptor antagonists, may have a deleterious effect on cognition in DLB.
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http://dx.doi.org/10.1002/syn.20441DOI Listing
November 2007

Dementia with Lewy bodies: a comparison of clinical diagnosis, FP-CIT single photon emission computed tomography imaging and autopsy.

J Neurol Neurosurg Psychiatry 2007 Nov 12;78(11):1176-81. Epub 2007 Mar 12.

University College London and Royal Free Hospitals, London, UK.

Background: Dementia with Lewy bodies (DLB) is a common form of dementia. The presence of Alzheimer's disease (AD) pathology modifies the clinical features of DLB, making it harder to distinguish DLB from AD clinically during life. Clinical diagnostic criteria for DLB applied at presentation can fail to identify up to 50% of cases. Our aim was to determine, in a series of patients with dementia in whom autopsy confirmation of diagnosis was available, whether functional imaging of the nigrostriatal pathway improves the accuracy of diagnosis compared with diagnosis by means of clinical criteria alone.

Methods: A single photon emission computed tomography (SPECT) scan was carried out with a dopaminergic presynaptic ligand [123I]-2beta-carbometoxy-3beta-(4-iodophenyl)-N-(3-fluoropropyl) nortropane (FP-CIT; ioflupane) on a group of patients with a clinical diagnosis of DLB or other dementia. An abnormal scan was defined as one in which right and left posterior putamen binding, measured semiquantitatively, was more than 2 SDs below the mean of the controls.

Results: Over a 10 year period it was possible to collect 20 patients who had been followed from the time of first assessment and time of scan through to death and subsequent detailed neuropathological autopsy. Eight patients fulfilled neuropathological diagnostic criteria for DLB. Nine patients had AD, mostly with coexisting cerebrovascular disease. Three patients had other diagnoses. The sensitivity of an initial clinical diagnosis of DLB was 75% and specificity was 42%. The sensitivity of the FP-CIT scan for the diagnosis of DLB was 88% and specificity was 100%.

Conclusion: FP-CIT SPECT scans substantially enhanced the accuracy of diagnosis of DLB by comparison with clinical criteria alone.
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http://dx.doi.org/10.1136/jnnp.2006.110122DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2117602PMC
November 2007

Heterogeneity of ubiquitin pathology in frontotemporal lobar degeneration: classification and relation to clinical phenotype.

Acta Neuropathol 2006 Nov 26;112(5):539-49. Epub 2006 Sep 26.

Department of Pathology, Vancouver General Hospital, V5Z 1M9, Vancouver, BC, Canada.

We have investigated the extent and pattern of immunostaining for ubiquitin protein (UBQ) in 60 patients with frontotemporal lobar degeneration (FTLD) with ubiquitin-positive, tau-negative inclusions (FTLD-U), 37 of whom were ascertained in Manchester UK and 23 in Newcastle-Upon-Tyne, UK. There were three distinct histological patterns according to the form and distribution of the UBQ pathology. Histological type 1 was present in 19 patients (32%) and characterised by the presence of a moderate number, or numerous, UBQ immunoreactive neurites and intraneuronal cytoplasmic inclusions within layer II of the frontal and temporal cerebral cortex, and cytoplasmic inclusions within granule cells of the dentate gyrus; neuronal intranuclear inclusions (NII) of a "cat's eye" or "lentiform" appearance were present in 17 of these patients. In histological type 2 (16 patients, 27%), UBQ neurites were predominantly, or exclusively, present with few intraneuronal cytoplasmic inclusions within layer II of the cerebral cortex, while in histological type 3 (25 patients, 42%), UBQ intraneuronal cytoplasmic inclusions either within the cortical layer II or in the granule cells of the dentate gyrus, with few or no UBQ neurites, were seen. In neither of these latter two groups were NII present. The influence of histological type on clinical phenotype was highly significant with type 1 histology being associated clinically with cases of frontotemporal dementia (FTD) or progressive non-fluent aphasia (PNFA), type 2 histology with semantic dementia (SD), and type 3 histology with FTD, or FTD and motor neurone disease (MND).
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http://dx.doi.org/10.1007/s00401-006-0138-9DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2668618PMC
November 2006

High levels of mitochondrial DNA deletions in substantia nigra neurons in aging and Parkinson disease.

Nat Genet 2006 May 9;38(5):515-7. Epub 2006 Apr 9.

Mitochondrial Research Group, School of Neurology, Neurobiology and Psychiatry, The Medical School, University of Newcastle upon Tyne, Newcastle upon Tyne, NE2 4HH, UK.

Here we show that in substantia nigra neurons from both aged controls and individuals with Parkinson disease, there is a high level of deleted mitochondrial DNA (mtDNA) (controls, 43.3% +/- 9.3%; individuals with Parkinson disease, 52.3% +/- 9.3%). These mtDNA mutations are somatic, with different clonally expanded deletions in individual cells, and high levels of these mutations are associated with respiratory chain deficiency. Our studies suggest that somatic mtDNA deletions are important in the selective neuronal loss observed in brain aging and in Parkinson disease.
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http://dx.doi.org/10.1038/ng1769DOI Listing
May 2006

Nicotinic acetylcholine receptor immunohistochemistry in Alzheimer's disease and dementia with Lewy bodies: differential neuronal and astroglial pathology.

J Neurol Sci 2004 Oct;225(1-2):39-49

Centre Development in Clinical Brain Aging, MRC Building, Newcastle General Hospital, Westgate Road, Newcastle upon Tyne, NE4 6BE, UK.

Alzheimer's disease (AD) and dementia with Lewy bodies (DLB) are common forms of dementia in the elderly. The neuropathology of AD and DLB is related to cholinergic dysfunctions, and both alpha4 and alpha7 nicotinic acetylcholine receptor (nAChR) subunits are decreased in several brain areas in both diseases. In this immunohistochemical study, we compared neuronal and astroglial alpha4 and alpha7 subunits in AD, DLB and age-matched controls in the hippocampal formation. The numbers of alpha4 reactive neurons were decreased in layer 3 of the entorhinal cortex of AD and DLB, whereas those of alpha7 reactive neurons were decreased in layer 2 of the subiculum of AD and DLB and in layer 3 of the entorhinal cortex of DLB. In contrast, the intensity of alpha7 reactive neuropil was significantly higher in AD than in controls or DLB in a number of areas of the hippocampus (CA3/4 and stratum granulosum), subiculum and entorhinal cortex. An increase in alpha7 immunoreactivity in AD was also associated with astrocytes. The number of astrocytes double-labelled with alpha7 and glial fibrillary acidic protein (GFAP) antibodies was increased in most areas of the hippocampus and entorhinal cortex in AD compared with controls and DLB. Increased astrocyte alpha7 nAChRs in AD may be associated with inflammatory mechanisms related to degenerative processes specific to this disease.
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http://dx.doi.org/10.1016/j.jns.2004.06.015DOI Listing
October 2004

alpha-Internexin aggregates are abundant in neuronal intermediate filament inclusion disease (NIFID) but rare in other neurodegenerative diseases.

Acta Neuropathol 2004 Sep 28;108(3):213-23. Epub 2004 May 28.

Center for Neurodegenerative Disease Research, Department of Pathology and Laboratory Medicine, University of Pennsylvania School of Medicine, 3600 Spruce Street, Philadelphia, PA 19104-4283, USA.

Abnormal neuronal aggregates of alpha-internexin and the three neurofilament (NF) subunits, NF-L, NF-M, and NF-H have recently been identified as the pathological hallmarks of neuronal intermediate filament (IF) inclusion disease (NIFID), a novel neurological disease of early onset with a variable clinical phenotype including frontotemporal dementia, pyramidal and extrapyramidal signs. alpha-Internexin, a class IV IF protein, a major component of inclusions in NIFID, has not previously been identified as a component of the pathological protein aggregates of any other neurodegenerative disease. Therefore, to determine the specificity of this protein, alpha-internexin immunohistochemistry was undertaken on cases of NIFID, non-tau frontotemporal dementias, motor neuron disease, alpha-synucleinopathies, tauopathies, and normal aged control brains. Our results indicate that class IV IF proteins are present within the pleomorphic inclusions of all cases of NIFID. Small subsets of abnormal neuronal inclusions in Alzheimer's disease, Lewy body diseases, and motor neuron disease also contain epitopes of alpha-internexin. Thus, alpha-internexin is a major component of the neuronal inclusions in NIFID and a relatively minor component of inclusions in other neurodegenerative diseases. The discovery of alpha-internexin in neuronal cytoplasmic inclusions implicates novel mechanisms of pathogenesis in NIFID and other neurological diseases with pathological filamentous neuronal inclusions.
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http://dx.doi.org/10.1007/s00401-004-0882-7DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3516855PMC
September 2004

alpha-internexin is present in the pathological inclusions of neuronal intermediate filament inclusion disease.

Am J Pathol 2004 Jun;164(6):2153-61

Department of Pathology and Laboratory Medicine, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania 19104-4283, USA.

Neuronal intermediate filament (IF) inclusion disease (NIFID) is a novel neurological disease of early onset with a variable clinical phenotype including frontotemporal dementia, pyramidal, and extrapyramidal signs. Pathologically, in affected areas, there is neuronal loss, astrocytosis, and neuronal intracytoplasmic aggregates of abnormal neuronal IFs that contain neither tau nor alpha-synuclein. Thus, to characterize the neuronal IF protein profile of inclusions in NIFID, immunohistochemistry (IHC) was performed on 10 cases of NIFID, four normal aged controls (NL), and two cases of Alzheimer's disease (AD) using a panel of anti-neuronal IF proteins. Immunoelectron microscopy was performed on selected cases and frozen tissue from the frontal lobe of four cases was used for biochemical studies including sequential extractions and Western blotting. Based on these studies, we report here for the first time that alpha-internexin, a neuronal IF protein, is present within the inclusions of NIFID as are all three neurofilament subunits: heavy, medium, and light. Thus, all class IV neuronal IF proteins are present within the pathological inclusions of this disease. Biochemistry revealed that IF aggregates were soluble in sodium dodecyl sulfate (SDS) and no post-translational modification was detected when compared with Alzheimer's disease or aged control brains. Hence, we conclude that NIFID is characterized by the pathological cytoplasmic aggregation of all class IV neuronal IF proteins in brain. The discovery of alpha-internexin in the cytoplasmic inclusions implicates novel mechanisms of pathogenesis in NIFID and other neurological diseases with pathological accumulations of IFs.
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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1615782PMC
http://dx.doi.org/10.1016/s0002-9440(10)63773-xDOI Listing
June 2004

Neuropathological substrates of psychiatric symptoms in prospectively studied patients with autopsy-confirmed dementia with lewy bodies.

Am J Psychiatry 2004 May;161(5):843-9

Newcastle General Hospital, Westgate Road, Newcastle upon Tyne NE4 6BE, UK.

Objective: This investigation was undertaken to clarify the neuropathological substrates of key psychiatric symptoms in dementia with Lewy bodies.

Method: The authors studied 112 autopsy-confirmed cases of dementia with Lewy bodies in patients who had had annual standardized clinical evaluations until their death. The relationships of persistent psychiatric symptoms (visual hallucinations, delusions, depression) to plaques (Consortium to Establish a Registry for Alzheimer's Disease protocol), tangles (Braak staging), and Lewy bodies (consensus Lewy body staging) were evaluated. In addition, symptom frequency and persistent symptoms were compared in the patients with Lewy body dementia and 90 patients with autopsy-confirmed Alzheimer's disease studied prospectively during life.

Results: The main neuropathological correlate of persistent visual hallucinations was the presence of less severe tangle pathology, but there was no significant association between tangle pathology and persistent delusions. Lewy body staging was associated with the presence of persistent visual hallucinations and persistent delusions. All baseline psychiatric features were significantly more frequent in dementia with Lewy bodies than in Alzheimer's disease, as were persistent visual hallucinations, but patients who had dementia with Lewy bodies and severe tangle pathology had a clinical symptom profile more similar to that of Alzheimer's disease patients and were less likely to have neocortical Lewy bodies.

Conclusions: The modest proportion of patients with Lewy body dementia and more severe tangle pathology resembled Alzheimer's disease patients clinically. Unlike Alzheimer's disease, dementia with Lewy bodies showed a significant inverse association between tangle burden and psychosis.
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http://dx.doi.org/10.1176/appi.ajp.161.5.843DOI Listing
May 2004

Muscarinic receptors in basal ganglia in dementia with Lewy bodies, Parkinson's disease and Alzheimer's disease.

J Chem Neuroanat 2003 Mar;25(3):161-73

MRC/University of Newcastle Centre in Clinical Brain Ageing, MRC Building, Newcastle General Hospital, Westgate Road, NE4 6BE, Newcastle-upon-Tyne, UK.

Derivatives of the muscarinic antagonist 3-quinuclidinyl-4-iodobenzilate (QNB), particularly [123I]-(R,R)-I-QNB, are currently being assessed as in vivo ligands to monitor muscarinic receptors in Alzheimer's disease (AD) and dementia with Lewy bodies (DLB), relating changes to disease symptoms and to treatment response with cholinergic medication. To assist in the evaluation of in vivo binding, muscarinic receptor density in post-mortem human brain was measured by autoradiography with [125I]-(R,R)-I-QNB and [125I]-(R,S)-I-QNB and compared to M1 ([3H]pirenzepine) and M2 and M4 ([3H]AF-DX 384) receptor binding. Binding was calculated in tissue containing striatum, globus pallidus (GPe), claustrum, and cingulate and insula cortex, in cases of AD, DLB, Parkinson's disease (PD) and normal elderly controls. Pirenzepine, AF-DX 384 and (R,S)-I-QNB binding in the striatum correlated positively with increased Alzheimer-type pathology, and AF-DX 384 and (R,R)-I-QNB cortical binding correlated positively with increased Lewy body (LB) pathology; however, striatal pirenzepine binding correlated negatively with cortical LB pathology. M1 receptors were significantly reduced in striatum in DLB compared to AD, PD, and controls and there was a significant correlation between M1 and dopamine D2 receptor densities. [3H]AF-DX 384 binding was higher in the striatum and GPe in AD. Binding of [125I]-(R,R)-I-QNB, which may reflect increased muscarinic M4 receptors, was higher in cortex and claustrum in DLB and AD. [125I]-(R,S)-I-QNB binding was higher in the GPe in AD. Low M1 and D2 receptors in DLB imply altered regulation of the striatal projection neurons which express these receptors. Low density of striatal M1 receptors may relate to the extent of movement disorder in DLB, and to a reduced risk of parkinsonism with acetylcholinesterase inhibition.
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http://dx.doi.org/10.1016/s0891-0618(03)00002-4DOI Listing
March 2003