Prion最新文献

Creutzfeldt-Jakob disease (CJD) is a rare, fatal disease presenting with rapidly progressive neurological deficits caused by the accumulation of a misfolded form (PrPSc) of prion protein (PrPc). Coronavirus disease 2019 (COVID-19) is a primarily respiratory syndrome caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2); many diverse neurological complications have been observed after COVID-19. We describe a young patient developing CJD two months after mild COVID-19. Presenting symptoms were visuospatial deficits and ataxia, evolving into a bedridden state with preserved consciousness and diffuse myoclonus. Diagnostic work-up was suggestive of CJD. The early age of onset and the short interval between respiratory and neurological symptoms might suggest a causal relationship: a COVID-19-related neuroinflammatory state may have induced the misfolding and subsequent aggregation of PrPSc. The present case emphasizes the link between neuroinflammation and protein misfolding. Further studies are needed to establish the role of SARS-CoV-2 as an initiator of neurodegeneration.

Prion diseases are a group of incurable zoonotic neurodegenerative diseases (NDDs) in humans and other animals caused by the prion proteins. The abnormal folding and aggregation of the soluble cellular prion proteins (PrP^C) into scrapie isoform (PrP^Sc) in the Central nervous system (CNS) resulted in brain damage and other neurological symptoms. Different therapeutic approaches, including stalling PrP^C to PrP^Sc conversion, increasing PrP^Sc removal, and PrP^C stabilization, for which a spectrum of compounds, ranging from organic compounds to antibodies, have been explored. Additionally, a non-PrP targeted drug strategy using serpin inhibitors has been discussed. Despite numerous scaffolds being screened for anti-prion activity in vitro, only a few were effective in vivo and unfortunately, almost none of them proved effective in the clinical studies, most likely due to toxicity and lack of permeability. Recently, encouraging results from a prion-protein monoclonal antibody, PRN100, were presented in the first human trial on CJD patients, which gives a hope for better future for the discovery of other new molecules to treat prion diseases. In this comprehensive review, we have re-visited the history and discussed various classes of anti-prion agents, their structure, mode of action, and toxicity. Understanding pathogenesis would be vital for developing future treatments for prion diseases. Based on the outcomes of existing therapies, new anti-prion agents could be identified/synthesized/designed with reduced toxicity and increased bioavailability, which could probably be effective in treating prion diseases.

Human prion diseases (PrDs) are a group of transmissible neurodegenerative diseases that can be clarified as sporadic, genetic and iatrogenic forms. In this study, we have analysed the time and geographic distributions of 2011 PrD cases diagnosed by China National Surveillance for Creutzfeldt-Jakob disease (CNS-CJD) since 2006, including 1792 sporadic CJD (sCJD) cases and 219 gPrD cases. Apparently, the cases numbers of both sCJD and gPrD increased along with the surveillance years, showing a stepping up every five years. The geographic distributions of the PrDs cases based on the permanent residences were wide, distributing in 30 out of 31 provincial-level administrative divisions in Chinese mainland. However, the case numbers in the provincial level varied largely. The provinces in the eastern part of China had much more cases than those in the western part. Normalized the case numbers with the total population each province revealed higher incidences in six provinces. Further, the resident and referring places of all PrD cases were analysed, illustrating a clear concentrating pattern of referring in the large metropolises. Five provincial-level administrative divisions reported more PrD cases from other provinces than the local ones. Particularly, BJ reported not only more than one-fourth of all PrDs cases in Chinese mainland but also 3.64-fold more PrDs cases from other provinces than its local ones. We believed that good medical resources, well-trained programmes and knowledge of PrDs in the clinicians and the CDC staffs contributed to well-referring PrD cases in those large cities.

Prion diseases are fatal and irreversible neurodegenerative diseases induced by the pathogenic form of the prion protein (PrP^Sc), which is converted from the benign form of the prion protein (PrP^C). These diseases are characterized by an extended asymptomatic incubation period accompanied by continuous conversion of PrP^C to PrP^Sc. However, to date, the mechanism governing the conversion to PrP^Sc in the initial stages of prion disease has not been fully elucidated. We collected transcriptome data from the hippocampus of wild-type mice and prion-infected mice at 8 weeks post injection from the Gene Expression Omnibus and analysed differentially expressed genes and related signalling biological process using bioinformatic tools. We identified a total of 36 differentially expressed genes, including 22 upregulated genes and 14 downregulated genes. In addition, we identified that the cilium-related biological process was enriched in the early stages of prion disease. Furthermore, up- and down-regulated genes were associated with cilium-related cellular components and synapse-related cellular components, respectively. To the best of our knowledge, our study was the first to observe the upregulation of cilium-related genes in the early stages of prion disease.

Chronic wasting disease (CWD) is a fatal encephalopathy affecting North American cervids. Certain alleles in a host's prion protein gene are responsible for reduced susceptibility to CWD. We assessed for the first time variability in the prion protein gene of elk (Cervus canadensis) present in Pennsylvania, United States of America, a reintroduced population for which CWD cases have never been reported. We sequenced the prion protein gene (PRNP) of 565 elk samples collected over 7 years (2014-2020) and found two polymorphic sites (codon 21 and codon 132). The allele associated with reduced susceptibility to CWD is present in the population, and there was no evidence of deviations from Hardy-Weinberg equilibrium in any of our sampling years (p-values between 0.14 and 1), consistent with the lack of selective pressure on the PRNP. The less susceptible genotypes were found in a frequency similar to the ones reported for elk populations in the states of Wyoming and South Dakota before CWD was detected. We calculated the proportion of less susceptible genotypes in each hunt zone in Pennsylvania as a proxy for their vulnerability to the establishment of CWD, and interpolated these results to obtain a surface representing expected proportion of the less susceptible genotypes across the area. Based on this analysis, hunt zones located in the southern part of our study area have a low proportion of less susceptible genotypes, which is discouraging for elk persistence in Pennsylvania given that these hunt zones are adjacent to the deer Disease Management Area 3, where CWD has been present since 2014.

An 84-year-old woman who had been diagnosed as having dementia with Lewy body (DLB) upon initial examination exhibited cognitive impairments and person delusional misidentification (DMS): she transiently claimed that her spouse was a stranger. She was re-examined at the age of 89 years; her frequency of speech and activities of daily living had both decreased, leading to verbal communication difficulties complicated by sensory aphasia, and brain diffusion-weighted (DW) magnetic resonance imaging (MRI) showed cortical hyperintensities in some areas of both hemispheres. About 4 months later, the DW high-intensity areas were observed to have expanded into diffuse cortical areas. While the clinical features of Creutzfeldt Jakob disease (CJD) (myoclonus; ataxia; parkinsonism; rapidly progressive cognitive impairments; periodic sharp discharges on electroencephalograms) were not observed, a genetic analysis of the prion protein (PRNP) gene, which was performed because of a family history of dementia, revealed a V180I mutation (heterozygosis: valine/isoleucine) suggesting genetic CJD (g-CJD). Her activity progressively decreased, reaching akinetic mutism about 11 months after the re-examination. Finally, she suffered from severe bedsores and died from aspiration pneumonia at the age of 90 years. The present report describes the first case of person DMS as an initial neuropsychiatric symptom for V180I g-CJD; the typical long-term clinical symptoms of CJD were not observed in this patient. The inclusion of person DMS as an initial clinical symptom and the presence of expansive cortical hyperintensity areas may be useful for clinicians attempting to diagnosis V180I g-CJD in patients with elusive symptoms.

Creutzfeldt-Jakob disease (CJD) is usually sporadic, but 10-15% of cases are caused by autosomal-dominant pathogenic variants in the prion protein gene (PRNP). A few PRNP variants show low penetrance. We report the case of a 64-year-old man, admitted to the ward with acute onset of aphasia; death occurred 6 weeks later. Brain MRI, EEG pattern and brain pathology were consistent with CJD diagnosis. Genetic analysis revealed a heterozygous V203I variant. We summarized the key clinical findings in patients carrying the V203I variant who were described to date. We also discuss the hypothesis as to whether V203I is a risk factor for CJD rather than a Mendelian disease-associated variant, as well as the possible implications of such hypothesis in the clinical scenario.

Engaging patients as partners in biomedical research has gradually gained consensus over the last two decades. They provide a different perspective on health priorities and help to improve design and outcomes of clinical studies. This paper describes the relationship established between scientists and members of a large family at genetic risk of very rare lethal disease, fatal familial insomnia (FFI). This interaction led to a clinical trial based on the repurposing of doxycycline - an antibiotic with a known safety profile and optimal blood-brain barrier passage - which in numerous preclinical and clinical studies had given evidence of its potential therapeutic effect in neurodegenerative disorders, including prion diseases like FFI. The design of this trial posed several challenges, which were addressed jointly by the scientists and the FFI family. Potential participants excluded the possibility of being informed of their own FFI genotype; thus, the trial design had to include both carriers of the FFI mutation (10 subjects), and non-carriers (15 subjects), who were given placebo. Periodic clinical controls were performed on both groups by blinded examiners. The lack of surrogate outcome measures of treatment efficacy has required to compare the incidence of the disease in the treated group with a historical dataset during 10 years of observation. The trial is expected to end in 2023. Regardless of the clinical outcome, it will provide worthwhile knowledge on the disease. It also offers an important example of public engagement and collaboration to improve the quality of clinical science.

Creutzfeldt-Jakob disease (CJD) is a low-prevalence, fatal neurodegenerative disease. Parkinsonism as first symptom of CJD is rare. We present a case manifesting difficulty falling asleep as unspecific prodromal symptom and parkinsonism as initial symptom. The patient received positron emission tomography/computed tomography (PET/CT) of dopamine transporter (DAT) using 18 F-FP-CIT. The DAT-scan demonstrated presynaptic dopaminergic deficit in bilateral posterior putamen, which supports the hypothesis of nigrostriatal pathway dysfunction in CJD.