Parkinson's disease (PD) is a common motor disorder of mysterious etiology. It is due to the progressive degeneration of the dopaminergic neurons of the substantia nigra and is accompanied by the a...

What Genetics Tells us About the Causes and Mechanisms of Parkinson's Disease

Clinical-pathological studies remain the gold-standard for the diagnosis of Parkinson's disease (PD). However, mounting data from genetic PD autopsies challenge the diagnosis of PD based on Lewy body pathology. Most of the confirmed genetic risks for PD show heterogenous neuropathology, even within kindreds, which may or may not include Lewy body pathology. We review the literature of genetic PD autopsies from cases with molecularly confirmed PD or parkinsonism and summarize main findings on SNCA (n = 25), Parkin (n = 20, 17 bi-allelic and 3 heterozygotes), PINK1 (n = 5, 1 bi-allelic and 4 heterozygotes), DJ-1 (n = 1), LRRK2 (n = 55), GBA (n = 10 Gaucher disease patients with parkinsonism), DNAJC13, GCH1, ATP13A2, PLA2G6 (n = 8 patients, 2 with PD), MPAN (n = 2), FBXO7, RAB39B, and ATXN2 (SCA2), as well as on 22q deletion syndrome (n = 3). Findings from autopsies of heterozygous mutation carriers of genes that are traditionally considered recessively inherited are also discussed. Lewy bodies may be present in syndromes clinically distinctive from PD (eg, MPAN-related neurodegeneration) and absent in patients with clinical PD syndrome (eg, LRRK2-PD or Parkin-PD). Therefore, the authors can conclude that the presence of Lewy bodies are not specific to the diagnosis of PD and that PD can be diagnosed even in the absence of Lewy body pathology. Interventions that reduce alpha-synuclein load may be more justified in SNCA-PD or GBA-PD than in other genetic forms of PD. The number of reported genetic PD autopsies remains small, and there are limited genotype-clinical-pathological-phenotype studies. Therefore, larger series of autopsies from genetic PD patients are required. © 2017 International Parkinson and Movement Disorder Society.

/pdf/neuropathology-of-genetic-synucleinopathies-with-2chgncwetg.pdf

Neuropathology of genetic synucleinopathies with parkinsonism: Review of the literature.

Iron dysregulation in movement disorders

The genetic landscape of Parkinson's disease.

BACKGROUND AND PURPOSE: MSA-P and IPD have similar clinical presentations that may complicate accurate clinical diagnosis. Different iron-deposition patterns of those 2 diseases have been demonstrated in histopathology. The aim was to demonstrate the different iron-deposition patterns of MSA-P and IPD by using SWI phase images. MATERIALS AND METHODS: Sixteen patients with IPD, 8 with MSA-P, and 44 age-matched healthy controls underwent SWI of brain. The different phase shifts as well as the high iron percentage of the area in several gray nuclei were statistically evaluated. The putamen was divided into 4 subregions for further analysis. RESULTS: Patients with MSA-P had significantly higher iron deposition in the putamen and PT compared with those with IPD ( P CONCLUSIONS: Higher iron deposition in the putamen and PT may differentiate MSA-P from IPD, but the lower inner region of the putamen may be better compared with the PT and other subregions of the putamen. Moreover, the high iron percentage makes it possible to detect smaller increases in iron content more confidently in comparison with average phase shift.

http://www.ajnr.org/content/ajnr/33/2/266.full.pdf

Different Iron-Deposition Patterns of Multiple System Atrophy with Predominant Parkinsonism and Idiopathetic Parkinson Diseases Demonstrated by Phase-Corrected Susceptibility-Weighted Imaging

Clinical phenotype of individuals with spinocerebellar ataxia 2 (SCA2) is characterised by cerebellar ataxia and cognitive impairment Although L-dopa-responsive Parkinsonism is considered as a rare clinical presentation in SCA2, it has been brought to the attention of many neurologists in several studies The authors report an autopsy case of SCA2 with Parkinsonism from a Japanese family using archival materials of our Brain Bank to describe unique neuropathologic findings The individual clinically showed Parkinsonism as a predominant phenotype instead of cerebellar ataxia Besides the classic SCA2 neuropathologic alterations, Lewy bodies and Lewy neurites were present in the brainstem nuclei Genetic analysis revealed shorter abnormal expansion of CAG repeats (less than 39) In contrast, the authors could not find α-synuclein pathology in two SCA2 cases without Parkinsonism The present case will provide a neuropathologic evidence of correlation between α-synucleinopathy and Parkinsonism of SCA2 as well as shed light on understanding the pathomechanism of Parkinsonism in SCA2

/pdf/spinocerebellar-ataxia-type-2-is-associated-with-40g5pezp9o.pdf

Spinocerebellar ataxia type 2 is associated with Parkinsonism and Lewy body pathology

OBJECTIVE We presented first two cases of multiple system atrophy (MSA) with a-/hypo-ceruloplasminemia (hypo-Cp). To know whether hypo-Cp was a cause of MSA, we investigated distribution of iron in brains. METHODS Investigating history, neurological sings and symptoms, neuroimagings, and neuropathological findings of the 2 cases, we demonstrate that these 2 cases were typical MSA. Serum ceruloplasmin (Cp) values of two cases were investigated, as well as those of 14 MSA patients diagnosed after the 2 cases. In the 2 cases, we compared distribution of lesions and distribution of iron depositions revealed by Berlin blue stain (iron stain). Further, we compared depositions of iron in substantia nigra, putamen, and dentate nucleus of the 2 cases with those of 4 control MSA, 2 Parkinson's disease (PD), 2 amyotrophic lateral sclerosis (ALS), and 3 controls. RESULTS Case 1 was 68-year-old man who developed gait disturbance, and had anti-Parkinson disease drugs after diagnosis of PD. Parkinsonism was progressed, and became bed-ridden after 6 years when he died. Neuropathological finding was typical MSA from distribution of lesions, as well as existence of GCIs and NCIs. Case 2 was 61-year-old man who developed parkinsonism. After 9 years, he had tracheostomy, and after 11 years died of renal failure. Neuropathological finding was typical MSA. With an investigation of serum Cp values of clinically diagnosed 14 MSA patients, we found 2 other cases of MSA with hypo-Cp. Iron stain of the 2 brains revealed that iron depositions were found in substantia nigra and putamen, but were not found neither in pontine base, cerebellum, nor inferior olive. Iron depositions were also seen in substantia nigra and putamen of control MSA cases as same degree as MSA with hypo-Cp, but iron depositions were fewer in PD, ALS and controls. CONCLUSION Clinico-pathological findings of the the 2 cases were those of typical MSA, but were not same as those of previously reported hypo-Cp. Previous reports suggested iron depositions as a cause of brain lesions, but, we concluded that, in the 2 cases, iron depositions were not a direct cause of MSA lesions. However, high incidence of association of hypo-Cp and MSA shown in our study suggests a relation between hypo-Cp and MSA.

[Multiple system atrophy with a-/hypo-ceruloplasminemia: distribution of iron in brains of 2 autopsy cases].

This is the first autopsy case of SCA2 with parkinsonian phenotype. At the age of 46, the patient got symptoms of parkinsonism to which anti-parkinsonian drugs were effective. He had mosaic 38, 40 CAG repeat expansions on chromosome 12q23-24, being diagnosed as SCA2, and his mother and his son also had CAG expansions on the same locus. In addition to parkinsonism, he also exhibited autonomic disturbance, dementia, and mild cerebellar ataxia Brain images revealed severe atrophy of pons and medulla oblongata, resembling MSA-C. HVA and 5-HIAA were reduced in the cerebrospinal fluid, and the heart-mediastinum (H/M) ratio in myocardial 123I-MIBG cintigram was decreased, which suggested Lewy body pathology. He died at the age of 75 and the autopsy revealed atrophy of the olivo-ponto-cerebellar (OPC) system and substantia nigra which was compatible to SCA2, although the OPC system atrophy was less severe than formerly reported SCA2 cases. The degrees of atrophy of the OPC system and substantia nigra might explain the predominancy of clinical symptoms. Anti-1C2 positive inclusions in the pontine nuclei, inferior olive nuclei, cerebellum and substantia nigra confirmed a polyglutamine disease. In addition, there were the anti-phosphorylated alpha-synuclein positive, Lewy body related pathological changes in the substantia nigra, the locus ceruleus, the dorsal motor nuclei of vagus, and the sympathetic nerve in the myocardium. Major genetic abnormalities related to Parkinson disease were not detected. As another case of SCA2 with Lewy body pathology was reported in Japan, the coexistence of SCA2 and Lewy body pathology may not be accidental. Since myocardial MIBG scincigram can predict Lewy body pathology, we should seek more clinical cases of SCA2 with Lewy body pathology.

Autopsy case of SCA2 with Parkinsonian phenotype

We reported a 69-year-old woman with multiple system atrophy (MSA), who had a heteroallelic missense mutation (G1874A, Gly-->Glu) in the exon 11 of the ceruloplasmin (Cp) gene. At the age of 64, she began to complain of progressive gait disturbance, which was resistant to anti-Parkinsonian drug treatment. Neurological examination revealed parkinsonism such as rigidity, akinesia, mild tremor and postural instability, accompanying saccadic eye movement, dysarthria, dysphagia, orthostatic hypotension and bladder disturbance. She showed neither cerebellar signs nor dementia. Serum Cp and copper concentrations were 13-18 mg/dl and 38-56 micrograms/dl, respectively, which were decreased to about a half of normal values. Brain MRIs revealed high intensity areas in the bilateral putamens in the T2-weighted image, and mild pontine base atrophy. She died of respiratory failure due to laryngeal paresis after five years from the onset. Neuropathological examination revealed brown-colored putamens, where there was severe neuronal cell loss with gliosis. Though atrophy of the pontine base was mild, transverse myelinated fibers were pale in Kluver-Barrera stain. There were Purkinje cell loss of moderate degree and appearance of torpedos in the cerebellum. Both silver staining and immunohistochemical staining to alpha-synuclein showed glial cytoplasmic inclusions, which were found predominantly in the putamens. These clinical features and neuropathological findings were compatible with multiple system atrophy (MSA). Iron staining of the brain revealed iron deposition in the putamens and the substantia nigra, but not in the pontine base nor in the cerebellum. Furthermore, we failed to reveal it in both the liver and the pancreas as well as the thalamus and the caudate nucleus, which were common sites of iron deposition in the previous cases of Cp gene mutation. We have already reported three other MSA cases with a- or hypo-ceruloplasminemia with similar clinical and pathological features to this case. One of them, in which gene analysis was also available, did not have any mutations in its Cp gene. Therefore, the gene mutation of this case may not be a direct cause to MSA, but the fact that the most cases of MSA with hypoceruloplasminemia showed striatonigral degeneration (SND) type implies some relationship between hypoceruloplasminemia and SND.

An autopsy case of multiple system atrophy with a heteroallelic ceruloplasmin gene mutation

A 46-year-old woman with a 15-month history of progressive dementia and personality changes was admitted to our hospital due to generalized seizures and a prolonged disturbance of consciousness. She tested positive for syphilis with a rapid plasma reagent. Fluorescent treponemal antibody absorption, measured for confirmation, was also positive. A human immunodeficiency virus test was negative. Axial fluid-attenuated inversion recovery magnetic resonance

Harumi Yomono

Papers

Spinocerebellar ataxia type 2 is associated with Parkinsonism and Lewy body pathology

[Multiple system atrophy with a-/hypo-ceruloplasminemia: distribution of iron in brains of 2 autopsy cases].

Autopsy case of SCA2 with Parkinsonian phenotype

An autopsy case of multiple system atrophy with a heteroallelic ceruloplasmin gene mutation

Neurosyphilis presenting as frontal and mesial temporal encephalitis.