Inflammation in Mild Cognitive Impairment due to Parkinson’s disease, Lewy Body disease and Alzheimer’s disease

Background Abstract Inflammation appears to play a role in the progression of neurodegenerative diseases. However, little is known about inflammation during early stages of cognitive decline or whether this differs in different disease groups. We sought to investigate this by assessing the inflammatory profile in patients with Parkinson’s disease with the early stages of cognitive impairment (PD-MCI), patients with prodromal Alzheimer’s disease (MCI-AD), prodromal Lewy Body disease (MCI-LB) and controls. Methods We obtained venous blood samples from participants with PD-MCI (n = 44), PD-normal cognition (n = 112) MCI-LB (n = 38), MCI-AD (n = 21) and controls (n = 84). We measured 10 cytokines using Meso Scale Discovery V-Plex Plus including interferon-gamma, interleukin (IL)-10, IL-12p70, IL-13, IL-1beta, IL- 2, IL-4, IL-6, IL-8 and tumour necrosis factor alpha. High-sensitivity C–reactive protein was measured. Results There was a higher level of inflammation in patients with MCI-AD and MCI-LB compared with controls. PD non-cognitively impaired had higher inflammatory markers than controls but there was no difference between PD-MCI and controls. There was a decrease in inflammatory markers with increasing motor severity based on the Unified Parkinson’s Disease Rating Scale. Conclusions Inflammation may be involved in the onset of cognitive decline in patients with MCI-AD and MCI-LB but appears to be less prominent PD-MCI albeit in a small data set. This suggests that anti- inflammatory medications may have most benefit at the earliest stages of neurodegenerative diseases. For PD cases, this might be in advance of the development of MCI.The LewyPro work was funded by the National Institute for Health Research (NIHR) Newcastle Biomedical Research Centre in Lewy Body Dementia based at Newcastle upon Tyne NHS Foundation Trust and Newcastle University and The Royal College of Psychiatrists Pathfinder Fellowship. ICICLE-PD was funded by Parkinson’s UK (J-0802, G-1507). The research was supported by the Lockhart Parkinson’s Disease Research Fund, the academy of Medical Sciences UK, the Rosetrees Trust, and the Stevenage Biosciences Catalyst, the National Institute for Health Research (NIHR) Newcastle Biomedical Research Unit based at Newcastle Upon Tyne Hospitals NHS Foundation Trust and Newcastle University and the NIHR Cambridge Biomedical Research Centre. CWG is supported by a Clinician Scientist Fellowship from the MRC

The Genetic Basis of Cognitive Impairment and Dementia in Parkinson's Disease.

Cognitive dysfunction is a common feature of Parkinson's disease (PD) with mild cognitive impairment affecting around a quarter of patients in the early stages of their disease, and approximately half developing dementia by 10 years from diagnosis. However, the pattern of cognitive impairments and their speed of evolution vary markedly between individuals. While some of this variability may relate to extrinsic factors and comorbidities, inherited genetic heterogeneity is also known to play an important role. A number of common genetic variants have been identified, which contribute to cognitive function in PD, including variants in catechol-O-methyltransferase, microtubule-associated protein tau, and apolipoprotein E. Furthermore, rarer mutations in glucocerebrosidase and α-synuclein and are strongly associated with dementia risk in PD. This review explores the functional impact of these variants on cognition in PD and discusses how such genotype-phenotype associations provide a window into the mechanistic basis of cognitive heterogeneity in this disorder. This has consequent implications for the development of much more targeted therapeutic strategies for cognitive symptoms in PD.This is the final version of the article. It first appeared from Frontiers via http://dx.doi.org/10.3389/fpsyt.2016.0008

Mild cognitive impairment and Parkinson's disease--something to remember.

Cognitive impairment is common in Parkinson's disease (PD), and many patients will eventually develop a dementia, which has a devastating impact on the patient and their family. As such, there has been much interest in identifying a prodromal state to inform prognosis and facilitate earlier management, similar to the concept of 'MCI' in the Alzheimer's field. However, grouping the early cognitive deficits of PD together as 'PD-MCI' may not be the best way forward as it implies a single aetiological basis with one clinical consequence. In this review, we argue that cognitive deficits in PD arise from a number of different pathological pathways, only some of which herald a dementing process. This has important implications both for treatment of individual patients, and for the design of future disease-modifying therapy trials.This is the final version of the article. It first appeared from IOS Press via http://dx.doi.org/10.3233/JPD-14042

Targeting Aged Astrocytes May Be a New Therapeutic Strategy in Parkinson's Disease.

Commentary on: Chinta, S. J. Woods, G. Demaria M. et al. Cellular Senescence Is Induced by the Environmental Neurotoxin Paraquat and Contributes to Neuropathology Linked to Parkinson’s Disease. Cell Reports 2018; 22: 930-940. Parkinson’s disease (PD) becomes increasingly common with advancing age. It is therefore possible that cell senescence contributes to its pathophysiology. In a recent paper in Cell Reports, Chinta et al1 have shown that astrocytes exhibiting an age-associated (senescent) phenotype are toxic to neurons in vitro, and their removal is associated with better outcomes in a mouse model of PD. This finding may be relevant to other neurodegenerative conditions such as Alzheimer’s and Amyotrophic Lateral Sclerosis (ALS) in which cellular senescence is also implicated.2CHWG holds a MRC Clinician Scientist fellowship, and receives grants from the Rosetrees Trust, the Evelyn Trust and Addenbrooke’s Charitable Trust. She is also supported by the NIHR Cambridge Biomedical Research Centre. KMS holds a fellowship from the Wellcome Trust and her work is also supported by the NIHR Cambridge Biomedical Research Centr

The pathogenesis of Parkinson's disease

Parkinson's disease is a progressive neurodegenerative condition associated with the deposition of aggregated α-synuclein. Insights into the pathogenesis of Parkinson's disease have been derived from genetics and molecular pathology. Biochemical studies, investigation of transplanted neurons in patients with Parkinson's disease, and cell and animal model studies suggest that abnormal aggregation of α-synuclein and spreading of pathology between the gut, brainstem, and higher brain regions probably underlie the development and progression of Parkinson's disease. At a cellular level, abnormal mitochondrial, lysosomal, and endosomal function can be identified in both monogenic and sporadic Parkinson's disease, suggesting multiple potential treatment approaches. Recent work has also highlighted maladaptive immune and inflammatory responses, possibly triggered in the gut, that accelerate the pathogenesis of Parkinson's disease. Although there are currently no disease-modifying treatments for Parkinson's disease, we now have a solid basis for the development of rational neuroprotective therapies that we hope will halt the progression of this disabling neurological condition

The motor and cognitive features of Parkinson's disease in patients with concurrent Gaucher disease over 2 years: a case series.

We report the cognitive features and progression of Parkinson's disease (PD) in five patients with concurrent Gaucher disease. The patients presented at an earlier age than patients with sporadic PD, as previously noted by others; but in contrast to many previous reports, our patients followed a variable clinical course. While two patients developed early cognitive deficits and dementia, three others remained cognitively intact over the follow-up period. Thus, in this small case series, PD in the context of GD more closely resembles idiopathic PD in terms of its clinical heterogeneity in contrast to PD associated with GBA heterozygote mutations.NIHR BRC and NIHR Senior Investigator, Rosetrees fundin

Motor complications in Parkinson's disease: 13-year follow-up of the CamPaIGN cohort.

BACKGROUND: Long-term population-representative data on motor fluctuations and levodopa-induced dyskinesias in Parkinson's disease is lacking. METHODS: The Cambridgeshire Parkinson's Incidence from GP to Neurologist (CamPaIGN) cohort comprises incident PD cases followed for up to 13 years (n = 141). Cumulative incidence of motor fluctuations and levodopa-induced dyskinesias and risk factors were assessed using Kaplan-Meyer and Cox regression analyses. RESULTS: Cumulative incidence of motor fluctuations and levodopa-induced dyskinesias was 54.3% and 14.5%, respectively, at 5 years and 100% and 55.7%, respectively, at 10 years. Higher baseline UPDRS-total and SNCA rs356219(A) predicted motor fluctuations, whereas higher baseline Mini-mental State Examination and GBA mutations predicted levodopa-induced dyskinesias. Early levodopa use did not predict motor complications. Both early motor fluctuations and levodopa-induced dyskinesias predicted reduced mortality in older patients (age at diagnosis >70 years). CONCLUSIONS: Our data support the hypothesis that motor complications are related to the severity of nigrostriatal pathology rather than early levodopa use and indicate that early motor complications do not necessarily confer a negative prognosis. © 2019 International Parkinson and Movement Disorder Society.This research was supported by Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education (2013-R1A1A2010499). CWG is supported by a Medical Research Council Clinician Scientist Fellowship. The CamPaIGN study was supported by the Wellcome Trust, the Medical Research Council, the Patrick Berthoud Trust, and the National Institute for Health Research (NIHR) Cambridge Biomedical Research Centre Dementia and Neurodegeneration Theme (Grant Reference Number 146281). RAB is an NIHR Senior Investigator

Neuroinflammation and protein pathology in Parkinson’s disease dementia

Abstract: Parkinson’s disease dementia is neuropathologically characterized by aggregates of α-synuclein (Lewy bodies) in limbic and neocortical areas of the brain with additional involvement of Alzheimer’s disease-type pathology. Whilst immune activation is well-described in Parkinson’s disease (PD), how it links to protein aggregation and its role in PD dementia has not been explored. We hypothesized that neuroinflammatory processes are a critical contributor to the pathology of PDD. To address this hypothesis, we examined 7 brain regions at postmortem from 17 PD patients with no dementia (PDND), 11 patients with PD dementia (PDD), and 14 age and sex-matched neurologically healthy controls. Digital quantification after immunohistochemical staining showed a significant increase in the severity of α-synuclein pathology in the hippocampus, entorhinal and occipitotemporal cortex of PDD compared to PDND cases. In contrast, there was no difference in either tau or amyloid-β pathology between the groups in any of the examined regions. Importantly, we found an increase in activated microglia in the amygdala of demented PD brains compared to controls which correlated significantly with the extent of α-synuclein pathology in this region. Significant infiltration of CD4+ T lymphocytes into the brain parenchyma was commonly observed in PDND and PDD cases compared to controls, in both the substantia nigra and the amygdala. Amongst PDND/PDD cases, CD4+ T cell counts in the amygdala correlated with activated microglia, α-synuclein and tau pathology. Upregulation of the pro-inflammatory cytokine interleukin 1β was also evident in the substantia nigra as well as the frontal cortex in PDND/PDD versus controls with a concomitant upregulation in Toll-like receptor 4 (TLR4) in these regions, as well as the amygdala. The evidence presented in this study show an increased immune response in limbic and cortical brain regions, including increased microglial activation, infiltration of T lymphocytes, upregulation of pro-inflammatory cytokines and TLR gene expression, which has not been previously reported in the postmortem PDD brain

Cerebrospinal Fluid Cytokines and Neurodegeneration-Associated Proteins in Parkinson's Disease.

INTRODUCTION: Immune markers are altered in Parkinson's disease (PD), but relationships between cerebrospinal fluid (CSF) and plasma cytokines and associations with neurodegeneration-associated proteins remain unclear. METHODS: CSF and plasma samples and demographic/clinical measures were obtained from 35 PD patients. CSF samples were analyzed for cytokines (together with plasma) and for α-synuclein, amyloid β(1-42) peptide, total tau, and phospho(Thr231)-tau. RESULTS: There were no CSF-plasma cytokine correlations. Interleukin (IL)-8 was higher and interferon-γ, IL-10, and tumor necrosis factor-α were lower in CSF versus plasma. In CSF, total tau correlated positively with IL-8 and IL-1β, whereas α-synuclein correlated positively with amyloid β(1-42) and negatively with semantic fluency (a known marker of PD dementia risk). DISCUSSION: CSF and peripheral cytokine profiles in PD are not closely related. Associations between CSF IL-8 and IL-1β and tau suggest that CSF inflammatory changes may relate to tau pathology within PD. CSF α-synuclein/amyloid β may reflect the risk of developing PD dementia. © 2020 The Authors. Movement Disorders published by Wiley Periodicals, Inc. on behalf of International Parkinson and Movement Disorder Society.Funding for this work was provided by the Rosetrees Trust (M369-F1), Addenbrooke’s Charitable Trust (PF15/CWG) and the NIHR Cambridge Biomedical Research Centre Dementia and Neurodegeneration Theme (146281). RSW was supported by a Fellowship from Addenbrooke’s Charitable Trust (RG77199). SFM was supported by the Transeuro EU FP7 grant (242003) and is now an NIHR Academic Clinical Fellow (ACF-2015-23-501). DPB is supported by a Wellcome Trust Clinical Research Career Development Fellowship. RAB is an NIHR Senior Investigator (NF-SI-0616-10011) and is supported by the Wellcome Trust-MRC Cambridge Stem Cell Institute. CHWG holds a RCUK/UKRI Research Innovation Fellowship awarded by the Medical Research Council (MR/R007446/1) and receives support from the Cambridge Centre for Parkinson-Plus

A common polymorphism in SNCA is associated with accelerated motor decline in GBA-Parkinson's disease.

A growing number of genetic susceptibility factors have been identified for Parkinson’s disease (PD). The combination of inherited risk variants is likely to affect not only risk of developing PD but also its clinical course. Variants in the GBA gene are particularly common, being found in approximately 5 to 10% of patients, and they lead to more rapid disease progression1. However, the effect of concomitant genetic risk factors on disease course in GBA-PD is not known.The CamPaIGN study has received financial support from the Wellcome Trust, the Medical Research Council, Parkinson’s UK and the Patrick Berthoud Trust. CHWG is supported by an RCUK/UKRI Innovation Fellowship awarded by the Medical Research Council. RAB is supported by the Wellcome Trust Stem Cell Institute (Cambridge). TBS received financial support from the Cure Parkinson’s Trust. The study is also supported by the National Institute for Health Research (NIHR) Cambridge Biomedical Research Centre Dementia and Neurodegeneration Theme (reference number 146281). The views expressed are those of the author(s) and not necessarily those of the NIHR or the Department of Health and Social Care. CRS' work is supported in part by NIH grants R01AG057331, U01NS100603, R01AG057331, and the American Parkinson Disease Association. Illumina MEGA Chip genotyping was made possible by a philanthropic investment from Dooley LLC (to Brigham & Women's Hospital and CRS)