Conflicting results from studies of Lewy-type α-synucleinopathy (LTS) in colonic biopsies of subjects with Parkinson's disease (PD) prompted a two-part multicenter assessment. The first assessment, ...now published (Acta Neuropathol Commun 4 : 35, 2016), examined archived colonic biopsies and found that none of the tested methods was adequately sensitive or specific.
As the amount of nervous tissue in typical colonic biopsies may be insufficient, and the clinical diagnosis of PD not completely accurate, the objective of the current study was to use instead full-thickness sections of sigmoid colon from autopsy-proven PD and normal subjects.
Seven different immunohistochemical (IHC) methods were used, employing five different primary antibodies and four different combinations of epitope exposure and signal development protocols. Specific staining was defined as being restricted to morphological features consistent with neuronal elements. Stained slides from each subject were independently categorized as being positive or negative for LTS, and their density semi-quantitatively graded, by four raters blinded to diagnosis.
Agreement and mean diagnostic performance varied markedly between raters. With the two most accurate raters, 5 methods achieved diagnostic accuracies of 70% or greater; one method had 100% accuracy and 100% inter-rater agreement. The submucosa had the highest prevalence of pathological LTS staining, followed by the muscularis and mucosa.
The major conclusion of this study is that, when sufficient submucosa and LTS is present, and when specific staining is defined as being consistent with neuronal morphology, adequately-trained raters may reliably distinguish PD colon from control using suitable IHC methods.
Abstract
We sought to determine the associations among cerebral amyloid angiopathy (CAA), white matter rarefaction (WMR), circle of Willis atherosclerosis (CWA), and total microinfarct number with ...Braak neurofibrillary stage in postmortem individuals with and without Alzheimer disease (AD). Data from 355 cases of autopsied individuals with Braak stage I–VI who had antemortem consensus diagnoses of cognitively unimpaired (n = 183), amnestic mild cognitive impairment (n = 31), and AD dementia (n = 141) were used. The association between Braak stage and vascular lesions were individually assessed using multivariable linear regression that adjusted for age at death, APOE ε4 carrier status, sex, education, and neuritic plaque density. CAA (p = 0.007) and WMR (p < 0.001) were associated with Braak stage, independent of amyloid load; microinfarct number and CWA showed no association. Analyses of the interactions between APOE ε4 carrier status and vascular lesions found that greater WMR and positive ε4 carrier status were associated with higher Braak stages. These results suggest that CAA and WMR are statistically linked to the severity of AD-related NFT pathology. The statistical link between WMR and NFT load may be strengthened by the presence of APOE ε4 carrier status. An additional finding was that Lewy body pathology was most prevalent in higher Braak stages.
Progranulin (PGRN) is a protein encoded by the GRN gene with multiple identified functions including as a neurotrophic factor, tumorigenic growth factor, anti-inflammatory cytokine and regulator of ...lysosomal function. A single mutation in the human GRN gene resulting in reduced PGRN expression causes types of frontotemporal lobar degeneration resulting in frontotemporal dementia. Prosaposin (PSAP) is also a multifunctional neuroprotective secreted protein and regulator of lysosomal function. Interactions of PGRN and PSAP affect their functional properties. Their roles in Alzheimer's disease (AD), the leading cause of dementia, have not been defined. In this report, we examined in detail the cellular expression of PGRN in middle temporal gyrus samples of a series of human brain cases (n = 45) staged for increasing plaque pathology. Immunohistochemistry showed PGRN expression in cortical neurons, microglia, cerebral vessels and amyloid beta (Aβ) plaques, while PSAP expression was mainly detected in neurons and Aβ plaques, and to a limited extent in astrocytes. We showed that there were increased levels of PGRN protein in AD cases and corresponding increased levels of PSAP. Levels of PGRN and PSAP protein positively correlated with amyloid beta (Aβ), with PGRN levels correlating with phosphorylated tau (serine 205) levels in these samples. Although PGRN colocalized with lysosomal-associated membrane protein-1 in neurons, most PGRN associated with Aβ plaques did not. Aβ plaques with PGRN and PSAP deposits were identified in the low plaque non-demented cases suggesting this was an early event in plaque formation. We did not observe PGRN-positive neurofibrillary tangles. Co-immunoprecipitation studies of PGRN from brain samples identified only PSAP associated with PGRN, not sortilin or other known PGRN-binding proteins, under conditions used. Most PGRN associated with Aβ plaques were immunoreactive for PSAP showing a high degree of colocalization of these proteins that did not change between disease groups. As PGRN supplementation has been considered as a therapeutic approach for AD, the possible involvement of PGRN and PSAP interactions in AD pathology needs to be further considered.
•Structural and functional retinal changes are present in Parkinson's disease (PD).•Phosphorylated α-synuclein (psyn) is a specific biomarker of PD.•Psyn-immunoreactive nerve fibers were present in ...the retina in 7/9 subjects with PD.•Psyn-immunoreactive neuronal perikarya were present in 1 PD subject.•This pathology may contribute to structural and functional retinal changes in PD.
Visual symptoms are relatively common in Parkinson's disease (PD) and optical coherence tomography has indicated possible retinal thinning. Accumulation of aggregated α-synuclein is thought to be a central pathogenic event in the PD brain but there have not as yet been reports of retinal synucleinopathy. Retinal wholemounts were prepared from subjects with a primary clinicopathological diagnosis of PD (N=9), dementia with Lewy bodies (DLB; N=3), Alzheimer's disease (N=3), progressive supranuclear palsy (N=2) as well as elderly normal control subjects (N=4). These were immunohistochemically stained with an antibody against α-synuclein phosphorylated at serine 129, which is a specific molecular marker of synucleinopathy. Phosphorylated α-synuclein-immunoreactive (p-syn IR) nerve fibers were present in 7/9 PD subjects and in 1/3 DLB subjects; these were sparsely distributed and superficially located near or at the inner retinal surface. The fibers were either long and straight or branching, often with multiple en-passant varicosities along their length. The straight fibers most often had an orientation that was radial with respect to the optic disk. Together, these features are suggestive of either retinopetal/centrifugal fibers or of ganglion cell axons. In one PD subject there were sparse p-syn IR neuronal cell bodies with dendritic morphology suggestive of G19 retinal ganglion cells or intrinsically photosensitive ganglion cells. There were no stained nerve fibers or other specific staining in any of the non-PD or non-DLB subjects. It is possible that at least some of the observed visual function impairments in PD subjects might be due to α-synucleinopathy.
ABSTRACTExisting reports on the frequencies of neurodegenerative diseases are typically based on clinical diagnoses. We sought to determine these frequencies in a prospectively assessed, ...community-based autopsy series. Included subjects had normal cognitive and movement disorder assessments at study entry. Of the 119 cases meeting these criteria, 52% were women; the median age of study entry was 83.5 years (range, 67–99 years), and the median duration from the first visit until death was 4.3 years (range, 0–10 years). At autopsy, clinicopathological diagnoses were made in 30 cases (25%). These diagnoses included 20 with Alzheimer disease (AD) (17%), 7 with vascular dementia (6%), 4 with progressive supranuclear palsy (3%), 3 with Parkinson disease and 1 each with dementia with Lewy bodies, corticobasal degeneration, or multiple system atrophy (0.8% each). Of the 87 subjects still clinically normal at death (73%), 33 had extensive AD pathology (preclinical AD) (38%), 17 had incidental Lewy bodies (20%), and 4 had incidental pathology consistent with progressive supranuclear palsy (5%). The diagnoses were not mutually exclusive. Although limited by a relatively small sample size, the neuropathological outcome of these initially normal elderly subjects represents a rough estimate of the incidence of these neurodegenerative conditions over a defined time period.
•aSyn density is similar in both submandibular glands of autopsied patients with Parkinson’s disease.•Parkinson’s disease duration correlated with submandibular gland aSyn density.•There was no ...evidence for significant tissue damage in previously biopsied submandibular glands.
Peripheral tissue biopsy in Parkinson’s disease (PD) may be valuable for clinical care, biomarker validation, and as research enrollment criteria.
Determine whether submandibular gland pathologic alpha-synuclein (aSyn) density is symmetrical and whether previous needle biopsy caused tissue damage.
Thirty autopsy-confirmed PD cases having fixed submandibular gland tissue from one side and frozen submandibular gland tissue from the contralateral side were studied. Tissue was stained for phosphorylated aSyn and density (0–4 semiquantitative scale) was determined. Three previously biopsied cases were also assessed for tissue damage at subsequent autopsy.
Mean (SD) age was 80.9 (5.5) years and disease duration 12.5 (9.3). Submandibular gland aSyn staining had a mean score of 2.13 for both the initially fixed and the initially frozen submandibular glands. The correlation between aSyn density of the two sides was r = 0.63. Correlation of aSyn density, in the originally fixed submandibular gland, with disease duration was good (r = 0.49, p =.006). No permanent tissue damage was found in the three previously biopsied cases.
This study found good correlation between aSyn density in both submandibular glands of patients with PD and found no evidence of significant tissue damage in previously biopsied subjects.
The Brain and Body Donation Program (BBDP) at Banner Sun Health Research Institute (http://www.brainandbodydonationprogram.org) started in 1987 with brain‐only donations and currently has banked more ...than 1600 brains. More than 430 whole‐body donations have been received since this service was commenced in 2005. The collective academic output of the BBDP is now described as the Arizona Study of Aging and Neurodegenerative Disorders (AZSAND). Most BBDP subjects are enrolled as cognitively normal volunteers residing in the retirement communities of metropolitan Phoenix, Arizona. Specific recruitment efforts are also directed at subjects with Alzheimer's disease, Parkinson's disease and cancer. The median age at death is 82. Subjects receive standardized general medical, neurological, neuropsychological and movement disorders assessments during life and more than 90% receive full pathological examinations by medically licensed pathologists after death. The Program has been funded through a combination of internal, federal and state of Arizona grants as well as user fees and pharmaceutical industry collaborations. Subsets of the Program are utilized by the US National Institute on Aging Arizona Alzheimer's Disease Core Center and the US National Institute of Neurological Disorders and Stroke National Brain and Tissue Resource for Parkinson's Disease and Related Disorders. Substantial funding has also been received from the Michael J. Fox Foundation for Parkinson's Research. The Program has made rapid autopsy a priority, with a 3.0‐hour median post‐mortem interval for the entire collection. The median RNA Integrity Number (RIN) for frozen brain and body tissue is 8.9 and 7.4, respectively. More than 2500 tissue requests have been served and currently about 200 are served annually. These requests have been made by more than 400 investigators located in 32 US states and 15 countries. Tissue from the BBDP has contributed to more than 350 publications and more than 200 grant‐funded projects.
Abstract Background Normal pressure hydrocephalus (NPH) is considered to be potentially treatable with the placement of a cerebrospinal fluid (CSF) shunt. However, the procedure has been reported to ...have variable success, particularly with respect to improving the cognitive impairment in NPH. The presence of neurologic comorbidities, particularly Alzheimer’s disease (AD), may contribute to shunt responsiveness. Uncovering the extent to which AD and NPH co-occur has implications for diagnosis and treatment of NPH. Autopsy studies of patients with NPH during their lifetime would elucidate the frequency of such comorbidities. Methods A search of the Sun Health Research Institute Brain Donation Program database was conducted between January 1, 1997 and April 1, 2009 to identify all cases with neuropathologic evidence of dementia as well as those of clinically diagnosed NPH. We reviewed the medical records and brain findings of each NPH case. Results Of the 761 cases autopsied over the study interval, 563 were found to have neuropathologic evidence meeting criteria for a dementing illness. Of 563 cases, AD was found exclusively in 313 (56%), and 94 suffered from secondary diagnosis of dementia. Nine of 761 cases were identified with a clinical diagnosis of NPH, which were among the 563 cases with neuropathology of dementing illness at autopsy, representing 1.6% (9/563) of the cases. On review of brain autopsy reports of these nine patients, eight (89%) were found to have AD and one (11%) had progressive supranuclear palsy. Review of the medical records of the nine NPH cases revealed the following clinical comorbidities: five suffered from AD, one from Parkinson’s Disease, one from mild cognitive impairment, and one from seizure disorder. Conclusions Given the findings of the present study, we support the AD-NPH theory and posit that AD is a common pathologic comorbidity in the setting of NPH and may preclude cognitive improvement postshunt placement. This may influence the selection of cases for shunting in the future.
Objective
Identify clinical features predictive of Lewy body pathology in Alzheimer's disease (AD) patients in an ongoing longitudinal clinicopathologic study.
Material and Methods
We queried the ...Arizona Study of Aging and Neurodegenerative Disorders (AZSAND) database for dementia cases with AD pathology (1997‐2015). Subjects received longitudinal comprehensive clinical evaluations including motor/neuropsychological assessment and Apo‐E4 genotyping. All cases were autopsied and had standard neuropathological assessments for AD and Lewy‐type synucleinopathy (LTS). Subjects were categorized based on standardized pathological criteria with AD cases that had LTS but did not meet DLB pathologic criteria being categorized as ADLB. We performed pairwise comparison between the different diagnoses and multivariable modelling to identify clinical symptoms that predict the pathological diagnosis.
Results
We identified 32 DLB/AD, 54 ADLB, 70 AD only and 41 PDD/AD cases. AD subjects with LTS pathology had higher UPDRS II and III total scores as well as generally higher individual scores compared to AD alone. While depression scales and Trail‐making Test A correlated significantly with LTS, other neuropsychological variables were not significantly different. Apo E4 occurrence was similar in all groups (40%‐49%).
Conclusions
Our study suggests that the presence (or absence) of LTS influences motor and non‐motor clinical findings in AD patients. These findings may lead to biomarkers that allow for more targeted treatment of AD.