The Role of Prion Protein in Reelin/Dab1 Signaling: Implications for Neurodegeneration.

The cellular prion protein (PrP) is studied in prion diseases, where its misfolded isoform (PrP) leads to neurodegeneration. PrP has also been implicated in several physiological functions. The protein is abundant in the nervous system, and it is critical for cell signaling in cellular communication, where it acts as a scaffold for various signaling molecules.

LC-MS/MS-Based Determination of Ambroxol in Human Plasma and Cerebrospinal Fluid: Validation and Applicability in a Phase II Study on GBA-Associated Parkinson's Disease Patients.

Heterozygous mutations in the gene, encoding the enzyme glucocerebrosidase (GCase), are major risk factors for Parkinson's Disease (PD). Ambroxol, a small chaperone originally used as a mucolytic agent, has been shown to cross the blood-brain barrier, enhance GCase activity, and reduce α-synuclein levels, making it a promising therapeutic candidate for disease-modifying effects in GBA1-associated PD (GBA1-PD). This study aimed to develop a method to quantify ambroxol levels in human plasma and cerebrospinal fluid (CSF) using liquid chromatography-tandem mass spectrometry (LC-MS/MS).

Poly-γ-glutamic acid alleviates cytotoxicity and inflammation induced by pre-formed fibrils of α-synuclein in murine primary astrocytes.

Poly-γ-glutamic acid (γ-PGA) is a bacterial-derived natural biopolymer that has gathered significant interest due to its antioxidant, anti-inflammatory, and neuroprotective properties. These characteristics make γ-PGA a potential candidate for the treatment of neurodegenerative diseases. In Parkinson's disease (PD), whose key pathological feature is the accumulation of neuronal α-synuclein aggregates, astrocytes, in addition to microglia, play a crucial role in clearing these aggregates; however, their capacity is limited.

Extracellular vesicles isolated from adipose tissue-derived mesenchymal stromal cells as carriers for Paclitaxel delivery.

Background: Mesenchymal Stromal Cells (MSC)-derived Extracellular Vesicles (EV) represent innovative tools for drug delivery systems. However, their clinical use is limited by the lack of standardized good manufacturing practice (GMP)-compliant isolation and conservation protocols. In this study, we developed a GMP-compliant protocol for the preparation of MSC-EVs and investigated the feasibility of producing EVs loaded with paclitaxel (PTX) for clinical application as drug products.

Exploring the impact of SerpinA3n deficiency on prion strains propagation.

Transmissible spongiform encephalopathies (TSEs) are a group of devastating neurodegenerative diseases characterized by the conversion of the normal cellular prion protein (PrP) into its misfolded, pathogenic form, PrP. Despite significant research, the exact molecular mechanisms driving PrP to PrP conversion remain elusive and are thought to involve multiple molecules or cofactors. One protein of interest, SERPINA3 (murine SerpinA3n), is an acute-phase protein, a member of the serine protease inhibitor family.

TDP-43 seeding activity in the olfactory mucosa of patients with amyotrophic lateral sclerosis.

Background: In recent years, the seed amplification assay (SAA) has enabled the identification of pathological TDP-43 in the cerebrospinal fluid (CSF) and olfactory mucosa (OM) of patients with genetic forms of frontotemporal dementia (FTD) and amyotrophic lateral sclerosis (ALS). Here, we investigated the seeding activity of TDP-43 in OM samples collected from patients with sporadic ALS.

Methods: OM samples were collected from patients with (a) sporadic motor neuron diseases (MND), including spinal ALS (n = 35), bulbar ALS (n = 18), primary lateral sclerosis (n = 10), and facial onset sensory and motor neuronopathy (n = 2); (b) genetic MND, including carriers of C9orf72 (n = 6), TARDBP (n = 4), SQSTM1 (n = 3), C9orf72 + SQSTM1 (n = 1), OPTN (n = 1), GLE1 (n = 1), FUS (n = 1) and SOD1 (n = 4) mutations; (c) other neurodegenerative disorders (OND), including Alzheimer's disease (n = 3), dementia with Lewy bodies (n = 8) and multiple system atrophy (n = 6); and (d) control subjects (n = 22).

Prions in Muscles of Cervids with Chronic Wasting Disease, Norway.

Chronic wasting disease (CWD) is an emerging prion disease in Nordic countries and has been detected in reindeer, moose, and red deer since 2016. CWD sporadically detected in moose and red deer in 3 Nordic countries demonstrated pathologic and strain characteristics different from CWD in reindeer, including an unexpected lack of prions outside the central nervous system as measured by standard diagnostic tests. Using protein misfolding cyclic amplification, we detected prions in the lymphoreticular system of moose and red deer with CWD in Norway and, remarkably, in muscles of both of those species and in CWD-infected reindeer.

α-Synuclein distribution in olfactory mucosa and skin nerves in Parkinson disease associated with an EIF4G1 gene mutation.

The EIF4G1 gene has been considered an autosomal dominant cause of Parkinson disease (PD), even if its role is still debated. The objective of this study was to describe the phenotype and α-synuclein distribution in peripheral tissues in 2 related PD patients (mother and daughter), who are carriers of the same variant in exon 10 of EIF4G1 (c.1216G>A, p.

Lewy pathology formation in patient-derived GBA1 Parkinson's disease midbrain organoids.

Fibrillary aggregation of α-synuclein in Lewy body inclusions and nigrostriatal dopaminergic neuron degeneration define Parkinson's disease neuropathology. Mutations in GBA1, encoding glucocerebrosidase, are the most frequent genetic risk factor for Parkinson's disease. However, the lack of reliable experimental models able to reproduce key neuropathological signatures has hampered clarification of the link between mutant glucocerebrosidase and Parkinson's disease pathology.

Unfolding Mechanism and Fibril Formation Propensity of Human Prion Protein in the Presence of Molecular Crowding Agents.

The pathological process of prion diseases implicates that the normal physiological cellular prion protein (PrP) converts into misfolded abnormal scrapie prion (PrP) through post-translational modifications that increase β-sheet conformation. We recently demonstrated that HuPrP(90-231) thermal unfolding is partially irreversible and characterized by an intermediate state (β-PrPI), which has been revealed to be involved in the initial stages of PrP fibrillation, with a seeding activity comparable to that of human infectious prions. In this study, we report the thermal unfolding characterization, in cell-mimicking conditions, of the truncated (HuPrP(90-231)) and full-length (HuPrP(23-231)) human prion protein by means of CD and NMR spectroscopy, revealing that HuPrP(90-231) thermal unfolding is characterized by two successive transitions, as in buffer solution.

Transmission of Norwegian reindeer CWD to sheep by intracerebral inoculation results in an unusual phenotype and prion distribution.

Chronic wasting disease (CWD), a prion disease affecting cervids, has been known in North America (NA) since the 1960s and emerged in Norway in 2016. Surveillance and studies have revealed that there are different forms of CWD in Fennoscandia: contagious CWD in Norwegian reindeer and sporadic CWD in moose and red deer. Experimental studies have demonstrated that NA CWD prions can infect various species, but thus far, there have been no reports of natural transmission to non-cervid species.

Tau seeding activity in skin biopsy differentiates tauopathies from synucleinopathies.

Most neurodegenerative diseases lack definitive diagnostic tests, and the identification of easily accessible and reliable biomarkers remains a critical unmet need. Since tau protein is highly expressed in skin of tauopathies patients, we aimed to exploit the ultrasensitive seeding activity assay (SAA) to assess tau seeding activity in skin of patients with tauopathies. In this multicentric, case-control study, patients with tauopathies and synucleinopathies were consecutively recruited and sex-matched to healthy controls (HC).

Combined 18F-FDG PET-CT markers in dementia with Lewy bodies.

Introduction: F-Fluoro-deoxyglucose-positron emission tomography (FDG-PET) is a supportive biomarker in dementia with Lewy bodies (DLB) diagnosis and its advanced analysis methods, including radiomics and machine learning (ML), were developed recently. The aim of this study was to evaluate the FDG-PET diagnostic performance in predicting a DLB versus Alzheimer's disease (AD) diagnosis.

Methods: FDG-PET scans were visually and semi-quantitatively analyzed in 61 patients.

Ambroxol as a disease-modifying treatment to reduce the risk of cognitive impairment in -associated Parkinson's disease: a multicentre, randomised, double-blind, placebo-controlled, phase II trial. The AMBITIOUS study protocol.

Background: Heterozygous mutations in the gene, encoding the lysosomal enzyme β-glucocerebrosidase (GCase), are the most frequent genetic risk factor for Parkinson's disease (PD). -related PD (GBA-PD) patients have higher risk of dementia and reduced survival than non-carriers. Preclinical studies and one open-label trial in humans demonstrated that the chaperone ambroxol (ABX) increases GCase levels and modulates α-synuclein levels in the blood and cerebrospinal fluid (CSF).

Secondary Protein Aggregates in Neurodegenerative Diseases: Almost the Rule Rather than the Exception.

The presence of protein aggregates is a hallmark of many neurodegenerative diseases, including Parkinson's disease (PD), Alzheimer's disease (AD), and frontotemporal lobar degeneration (FTLD). Traditionally, each disease has been associated with the aggregation of specific proteins, which serve as disease-specific biomarkers. For example, aggregates of α-synuclein (α-syn) are found in α-synucleinopathies such as PD, dementia with Lewy bodies (DLB), and multiple system atrophy (MSA).

Different tau fibril types reduce prion level in chronically and de novo infected cells.

Neurodegenerative diseases are often characterized by the codeposition of different amyloidogenic proteins, normally defining distinct proteinopathies. An example is represented by prion diseases, where the classical deposition of the aberrant conformational isoform of the prion protein (PrP) can be associated with tau insoluble species, which are usually involved in another class of diseases called tauopathies. How this copresence of amyloidogenic proteins can influence the progression of prion diseases is still a matter of debate.

Corrigendum: PMCA-based detection of prions in the olfactory mucosa of patients with sporadic Creutzfeldt-Jakob disease.

[This corrects the article DOI: 10.3389/fnagi.2022.

Semantic and right temporal variant of FTD: Next generation sequencing genetic analysis on a single-center cohort.

Semantic and right temporal variant of frontotemporal dementia (svFTD and rtvFTD) are rare clinical phenotypes in which, in most cases, the underlying pathology is TDP-43 proteinopathy. They are usually sporadic disorders, but recent evidences suggest a higher frequency of genetic mutations for the right temporal versus the semantic variant. However, the genetic basis of these forms is not clear.

Bifunctional carbazole derivatives for simultaneous therapy and fluorescence imaging in prion disease murine cell models.

Prion diseases are characterized by the self-assembly of pathogenic misfolded scrapie isoforms (PrP) of the cellular prion protein (PrP). In an effort to achieve a theranostic profile, symmetrical bifunctional carbazole derivatives were designed as fluorescent rigid analogues of GN8, a pharmacological chaperone that stabilizes the native PrP conformation and prevents its pathogenic conversion. A focused library was synthesized via a four-step route, and a representative member was confirmed to have native fluorescence, including a band in the near-infrared region.