Tauopathies with parkinsonism represent a spectrum of disease entities unified by the pathologic accumulation of hyperphosphorylated tau protein fragments within the central nervous system. These ...pathologic characteristics suggest shared pathogenetic pathways and possible molecular targets for disease‐modifying therapeutic interventions. Natural history studies, for instance, in progressive supranuclear palsy, frontotemporal dementia with parkinsonism linked to chromosome 17, corticobasal degeneration, and Niemann‐Pick disease type C as well as in amyotrophic lateral sclerosis/Parkinson–dementia complex permit clinical characterization of the disease phenotypes and are crucial to the development and validation of biological markers for differential diagnostics and disease monitoring, for example, by use of neuroimaging or proteomic approaches. The wide pathologic and clinical spectrum of the tauopathies with parkinsonism is reviewed in this article, and perspectives on future advances in the understanding of the pathogenesis are given, together with potential therapeutic strategies.
A case of late onset GM2 gangliosidodis with spinal muscular atrophy phenotype followed by cerebellar and extrapyramidal symptoms is presented. Genetic analysis revealed compound heterozygous ...mutation in exon 10 of the HEXA gene. Patient has normal intelligence and emotional reactivity. Neuroimaging tests of the brain showed only cerebellar atrophy consistent with MR spectroscopy (MRS) abnormalities. (18)F-fluorodeoxyglucose positron emission tomography (18)F-FDG PET/CT of the brain revealed glucose hypometabolism in cerebellum and in temporal and occipital lobes bilaterally.
•Late onset GM2 with spinal SMA phenotype followed by cerebellar symptoms and dystonia.•Compound heterozygous mutation in exon 10 of the HEXA gene.•MRI of the brain showed cerebellar atrophy consistent with MRS abnormalities.•FDG PET/CT showed hypometabolism in cerebellum and in temporal and occipital cortex.
Inclusion body myopathy associated with Paget disease of bone and frontotemporal dementia (IBMPFD, OMIM 167320) has recently been attributed to eight missense mutations in valosin‐containing protein ...(VCP). We report novel VCP mutations N387H and L198W in six individuals from two families who presented with proximal muscle weakness at a mean age of diagnosis of 40 years, most losing the ability to walk within a few years of onset. Electromyographic studies in four individuals were suggestive of ‘myopathic’ changes, and neuropathic pattern was identified in one individual in family 1. Muscle biopsy in four individuals showed myopathic changes characterized by variable fiber size, two individuals showing rimmed vacuoles and IBM‐type cytoplasmic inclusions in muscle fibers, and electron microscopy in one individual revealing abundant intranuclear inclusions. Frontotemporal dementia associated with characteristic behavioral changes including short‐term memory loss, language difficulty, and antisocial behavior was observed in three individuals at a mean age of 47 years. Detailed brain pathology in one individual showed cortical degenerative changes, most severe in the temporal lobe and hippocampus. Abundant ubiquitin‐positive tau‐, α‐synuclein‐, polyglutamine repeat‐negative neuronal intranuclear inclusions and only rare intracytoplasmic VCP positive inclusions were seen. These new mutations may cause structural changes in VCP and provide some insight into the functional effects of pathogenic mutations.
Two recent studies identified a mutation (p.Asp620Asn) in the vacuolar protein sorting 35 gene as a cause for an autosomal dominant form of Parkinson disease . Although additional missense variants ...were described, their pathogenic role yet remains inconclusive.
We performed the largest multi-center study to ascertain the frequency and pathogenicity of the reported vacuolar protein sorting 35 gene variants in more than 15,000 individuals worldwide. p.Asp620Asn was detected in 5 familial and 2 sporadic PD cases and not in healthy controls, p.Leu774Met in 6 cases and 1 control, p.Gly51Ser in 3 cases and 2 controls. Overall analyses did not reveal any significant increased risk for p.Leu774Met and p.Gly51Ser in our cohort.
Our study apart from identifying the p.Asp620Asn variant in familial cases also identified it in idiopathic Parkinson disease cases, and thus provides genetic evidence for a role of p.Asp620Asn in Parkinson disease in different populations worldwide.
Objectives ‐ An autoimmune basis has been implicated in the pathogenesis of amyotrophic lateral sclerosis (ALS). This hypothesis is supported by the presence of antibodies that interact with ...motoneuron antigens in serum of these patients. Against autoimmunity are the discrepances in the frequency of the antibodies appearance and also failure of immunosuppression. The aim of our study was to evaluate the titer of antibodies against GM1‐gangliosides, AGM1‐gangliosides and anti‐sulfatides in paired serum and cerebrospinal fluid samples in the ALS patients. Material and methods ‐ Serum of 103 and CSF of 79 patients with ALS was examined. The “disease controls” consisted of 22 cases of other motor neuron diseases and 50 healthy, age‐matched normals. CSF was drawn at the same time from 79 ALS patients, 6 cases of the “disease controls” and 50 normals. To study the titer of antibodies against GM1‐gangliosides, AGM1‐gangliosides and sulfatides the ELISA technique has been applied. Results ‐ An increased titer against GM1‐gangliosides, AGM1‐gangliosides and sulfatides in ALS appeared in serum in 18%, 32% and 11%, resp., in the “disease controls” the increased antibodies titer appeared in single cases. In CSF the appropriate values in ALS were 20%, 15%, 8%, resp. In the “disease controls” a high antibodies titer was a rare finding. Conclusions ‐ It is concluded that in some ALS cases and also in some patients with other motor neuron diseases an autoimmune mechanism may contribute to motor neuron injury.
Glutathione S-transferase (GST, EC 2.5.1.18) is an enzyme responsible for inactivation of a large variety of toxic, electrophilic compounds and organic peroxides. GST activity and GST pi expression ...were studied in patients with amyotrophic lateral sclerosis (ALS). Studies were conducted on cerebrospinal fluid (CSF), blood serum and peripheral blood mononuclear cells (PBMC) obtained from 40 ALS patients. CSF from 30 subjects without neurological diseases and blood from 40 healthy blood donors were used as controls. GST activity assayed with 1-chloro-2,4-dinitrobenzene (substrate for transferase activity) and cumene peroxide (substrate for peroxidase activity) was significantly decreased in PBMC of ALS patients, as well as the GST pi expression on both mRNA and protein level. The mean peroxidase activity was however significantly increased in CSF and serum of ALS patients with the specificity of 80% and 73%, and the sensitivity of 78% and 85%, respectively.
It can thus be concluded that the protective barrier formed by GST is originally affected in peripheral blood of ALS patients, and may increase their vulnerability to toxic effects of electrophilic compounds and organic peroxides. Studies on a larger group are needed to answer the question whether GSH-Px determination may be implicated in the diagnosis of ALS.