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1.
Yale J Biol Med ; 97(2): 141-152, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38947105

ABSTRACT

Nodal regions, areas of intensive contact between Schwann cells and axons, may be exceptionally vulnerable to diabetes-induced changes because they are exposed to and impacted by the metabolic implications of diabetes. Insulin receptors, glucose transporters, Na+ and K+ channels, and mitochondria are abundant in nodes, all of which have been linked to the development and progression of Diabetic Peripheral Neuropathy (DPN) and Type 1 Diabetes Mellitus (T1DM)-associated cognitive impairment. Our study aimed to evaluate if the administration of Nigella sativa (NS) and Cassia angustifolia (CA) prevented diabetes-associated nervous system deficits in hyperglycemic mice. We developed T1DM mice through Streptozotocin (STZ) injections and validated the elevations in blood glucose levels. NS and CA were administered immediately upon the induction of diabetes. Behavioral analysis, histopathological evaluations, and assessment of molecular biomarkers (NR2A, MPZ, NfL) were performed to assess neuropathy and cognitive impairment. Improvements in memory, myelin loss, and the expression of synaptic proteins, even with the retention of hyperglycemia, were evident in the mice who were given a dose of herbal products upon the detection of hyperglycemia. NS was more beneficial in preventing memory impairments, demyelination, and synaptic dysfunction. The findings indicate that including these herbs in the diets of diabetic as well as pre-diabetic patients can reduce complications associated with T1DM, notably diabetic peripheral neuropathy and cognitive deficits associated with T1DM.


Subject(s)
Cognitive Dysfunction , Diabetic Neuropathies , Nigella sativa , Animals , Diabetic Neuropathies/drug therapy , Diabetic Neuropathies/prevention & control , Nigella sativa/chemistry , Mice , Cognitive Dysfunction/drug therapy , Cognitive Dysfunction/prevention & control , Cognitive Dysfunction/etiology , Male , Diabetes Mellitus, Experimental/complications , Diabetes Mellitus, Experimental/drug therapy , Plant Extracts/pharmacology , Plants, Medicinal/chemistry , Senna Plant
2.
Yale J Biol Med ; 97(2): 153-164, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38947101

ABSTRACT

The blood-brain barrier (BBB) prevents the use of many drugs for the treatment of neurological disorders. Recently, nitrogen-doped carbon dots (NCDs) have emerged as promising nanocarriers to cross BBB. The primary focus of our study was to evaluate the effectiveness of NCDs for the symptomatic treatment of Alzheimer's disease (AD). In this study, we developed and characterized NCDs bound to rutin, a flavonoid with known benefits for AD. Despite its benefits, the transportation of rutin via NCDs for AD therapy has not been explored previously. We characterized the particles using FTIR and UV-visible spectroscopy followed by atomic force microscopy. Once the design was optimized and validated, we performed in vivo testing via a hemolytic assay to optimize the dosage. Preliminary in vitro testing was performed in AlCl3-induced rat models of AD whereby a single dose of 10 mg/kg NCDs-rutin was administered intraperitoneally. Interestingly, this single dose of 10 mg/kg NCDs-rutin produced the same behavioral effects as 50 mg/kg rutin administered intraperitoneally for 1 month. Similarly, histological and biomarker profiles (SOD2 and TLR4) also presented significant protective effects of NCDs-rutin against neuronal loss, inflammation, and oxidative stress. Hence, NCDs-rutin are a promising approach for the treatment of neurological diseases.


Subject(s)
Alzheimer Disease , Carbon , Glucose , Nitrogen , Rutin , Rutin/pharmacology , Rutin/chemistry , Animals , Alzheimer Disease/drug therapy , Alzheimer Disease/metabolism , Carbon/chemistry , Carbon/pharmacology , Nitrogen/chemistry , Rats , Glucose/metabolism , Male , Quantum Dots/chemistry , Disease Models, Animal , Oxidative Stress/drug effects , Humans
3.
Environ Monit Assess ; 196(5): 412, 2024 Apr 02.
Article in English | MEDLINE | ID: mdl-38565815

ABSTRACT

Cadmium (Cd) is a highly toxic metal that frequently contaminates our environment. In this study, the bioflocculant-producing, cadmium-resistant Escherichia fergusonii ZSF-15 was characterized from Paharang drain, Bawa Chak, Faisalabad, Pakistan. The Cd-resistant E. fergusonii was used to determine the bioflocculant production using yeast-peptone-glycerol medium (pH 6.5) supplemented with 50 mg L-1 of Cd. The culture was incubated for 3 days at 37 °C in a rotary shaker at 120 rpm. The fermentation broth was centrifuged at 4000 g for 10 min after the incubation period. The maximum flocculating activity by isolate ZSF-15 was found to be 71.4% after 48 h of incubation. According to the Fourier transform infrared spectroscopy analysis, the bioflocculant produced by strain ZSF-15 was comprised of typical polysaccharide and protein, i.e. hydroxyl, carboxyl, and amino groups. The strain ZSF-15 exhibited bioflocculant activity at range of pH (6-8) and temperature (35-50℃). Maximum flocculation activity (i.e. 71%) was observed at 47℃, whereas 63% flocculation production was observed at pH 8. In the present study, antioxidant enzyme profile of ZSF-15 was also evaluated under cadmium stress. A significant increase in antioxidant enzymes including superoxide dismutase (118%) and ascorbate peroxidase (28%) was observed, whereas contents of catalase (86%), glutathione transferase (13%), and peroxidase (8%) were decreased as compared to control.


Subject(s)
Antioxidants , Cadmium , Escherichia , Cadmium/toxicity , Hydrogen-Ion Concentration , Environmental Monitoring , Flocculation
4.
Prion ; 18(1): 11-27, 2024 Dec.
Article in English | MEDLINE | ID: mdl-38323574

ABSTRACT

Creutzfeldt Jakob Disease (CJD) is a rapidly progressive, fatal neurodegenerative disorder, also known as a subacute spongiform encephalopathy. There are three major subtypes of CJD i.e. Sporadic CJD, which occurs for reasons unbeknown to science (85% of known cases), Genetic or Familial CJD which is characterized by the presence of mutations in the human prion protein (PRNP) gene (10-15% cases) and Iatrogenic CJD that occurs via accidental transmission through medical and surgical procedures (1-2% cases). CJD cases occur globally with 1 case per one million population/year. Considerable data is available related to the incidence and prevalence of CJD in Europe and America. However, the global surveillance database is yet to include Asia even though several Asian countries have their own CJD monitoring units. sCJD is the highest among all CJD cases in Asia. China (1957) and Japan (1705) have reported more cases of sCJD than any Asian country and Hong Kong (1) has reported the least. On the other hand, gCJD is highest in Japan (370) and least in India (2). Our analysis establishes the presence of all variants of CJD across Asia. However, in most Asian countries in general and Southeast Asian countries in particular, CJD cases are misdiagnosed and often underreported. Since Asia is the most populated continent in the world, the actual global prevalence of CJD cannot be estimated until and unless these countries are accounted for. Concrete and reliable surveillance networks are needed across Asia to evaluate the prevalence and incidence of CJD in the region. [Figure: see text]The graphical abstract demonstrates the prevalence of CJD cases in the world and systematically analyses the incidence of CJD in Asian countries between the year 1986-2022. Highest number of cases were reported in Japan followed by China. The study emphasizes the need for assimilation of Asian data in global prevalence.


Subject(s)
Creutzfeldt-Jakob Syndrome , Prions , Humans , Creutzfeldt-Jakob Syndrome/genetics , Prions/genetics , Prion Proteins , Asia
5.
Biomolecules ; 14(1)2024 Jan 16.
Article in English | MEDLINE | ID: mdl-38254718

ABSTRACT

Neurodegenerative disorders, such as Parkinson's disease, Alzheimer's disease, and Huntington's disease, are identified and characterized by the progressive loss of neurons and neuronal dysfunction, resulting in cognitive and motor impairment. Recent research has shown the importance of PTMs, such as phosphorylation, acetylation, methylation, ubiquitination, sumoylation, nitration, truncation, O-GlcNAcylation, and hydroxylation, in the progression of neurodegenerative disorders. PTMs can alter protein structure and function, affecting protein stability, localization, interactions, and enzymatic activity. Aberrant PTMs can lead to protein misfolding and aggregation, impaired degradation, and clearance, and ultimately, to neuronal dysfunction and death. The main objective of this review is to provide an overview of the PTMs involved in neurodegeneration, their underlying mechanisms, methods to isolate PTMs, and the potential therapeutic targets for these disorders. The PTMs discussed in this article include tau phosphorylation, α-synuclein and Huntingtin ubiquitination, histone acetylation and methylation, and RNA modifications. Understanding the role of PTMs in neurodegenerative diseases may provide new therapeutic strategies for these devastating disorders.


Subject(s)
Alzheimer Disease , Protein Processing, Post-Translational , Humans , Phosphorylation , Ubiquitination , Acetylation
6.
Cell Biosci ; 13(1): 221, 2023 Dec 01.
Article in English | MEDLINE | ID: mdl-38041189

ABSTRACT

BACKGROUND: Aberrant stress granules (SGs) are emerging as prime suspects in the nucleation of toxic protein aggregates. Understanding the molecular networks linked with aggregation-prone proteins (prion protein, synuclein, and tau) under stressful environments is crucial to understand pathophysiological cascades associated with these proteins. METHODS: We characterized and validated oxidative stress-induced molecular network changes of endogenous aggregation-prone proteins (prion protein, synuclein, and tau) by employing immunoprecipitation coupled with mass spectrometry analysis under basal and oxidative stress conditions. We used two different cell models (SH-SY5Y: human neuroblastoma and HeLa cell line) to induce oxidative stress using a well-known inducer (sodium arsenite) of oxidative stress. RESULTS: Overall, we identified 597 proteins as potential interaction partners. Our comparative interactome mapping provides comprehensive network reorganizations of three aggregation-prone hallmark proteins, establish novel interacting partners and their dysregulation, and validates that prion protein and synuclein localize in cytoplasmic SGs. Localization of prion protein and synuclein in TIA1-positive SGs provides an important link between SG pathobiology and aggregation-prone proteins. In addition, dysregulation (downregulation) of prion protein and exportin-5 protein, and translocation of exportin-5 into the nucleus under oxidative stress shed light on nucleocytoplasmic transport defects during the stress response. CONCLUSIONS: The current study contributes to our understanding of stress-mediated network rearrangements and posttranslational modifications of prion/prion-like proteins. Localization of prion protein and synuclein in the cytoplasmic SGs provides an important link between stress granule pathobiology and aggregation-prone proteins. In addition, our findings demonstrate nucleocytoplasmic transport defects after oxidative stress via dysregulation and nuclear accumulation of exportin-5.

7.
Cells ; 12(16)2023 08 12.
Article in English | MEDLINE | ID: mdl-37626863

ABSTRACT

Fatal familial insomnia (FFI) is a rare autosomal-dominant inherited prion disease with a wide variability in age of onset. Its causes are not known. In the present study, we aimed to analyze genetic risk factors other than the prion protein gene (PRNP), in FFI patients with varying ages of onset. Whole-exome sequencing (WES) analysis was performed for twenty-five individuals with FFI (D178N-129M). Gene ontology enrichment analysis was carried out by Reactome to generate hypotheses regarding the biological processes of the identified genes. In the present study, we used a statistical approach tailored to the specifics of the data and identified nineteen potential gene variants with a potential effect on the age of onset. Evidence for potential disease modulatory risk loci was observed in two pseudogenes (NR1H5P, GNA13P1) and three protein coding genes (EXOC1L, SRSF11 and MSANTD3). These genetic variants are absent in FFI patients with early disease onset (19-40 years). The biological function of these genes and PRNP is associated with programmed cell death, caspase-mediated cleavage of cytoskeletal proteins and apoptotic cleavage of cellular proteins. In conclusions, our study provided first evidence for the involvement of genetic risk factors additional to PRNP, which may influence the onset of clinical symptoms in FFI.


Subject(s)
Insomnia, Fatal Familial , Prions , Humans , Insomnia, Fatal Familial/genetics , Exome Sequencing , Age of Onset , Genes, Regulator , Prion Proteins/genetics
8.
Fitoterapia ; 169: 105612, 2023 Sep.
Article in English | MEDLINE | ID: mdl-37454777

ABSTRACT

Since long, medicinal plants or herbs are being used in different traditional treatment systems as therapeutic agents to treat a variety of illnesses. Bixa orellana L., an medicinal plant (family: Bixaceae), is an Ayurvedic herb used to treat dyslipidemia, diarrhoea, and hepatitis since ancient times. B. orellana L., seeds contain an orange-red coloured component known as bixin (C25H30O4), which constitutes 80% of the extract.Chemically, bixin is a natural apocarotenoid, biosynthesized through the oxidative degradation of C40 carotenoids. Bixin helps to regulate the Nrf2/MyD88/TLR4 and TGF-1/PPAR-/Smad3 pathways, which further give it antifibrosis, antioxidant, and anti-inflammatory properties. This current review article presents a comprehensive review of bixin as an anti-inflammatory, antioxidant, anticancer,and skin protecting natural product. In addition, the biosynthesis and molecular target of bixin, along with bixin extraction techniques, are also presented.


Subject(s)
Biological Products , Plants, Medicinal , Antioxidants/pharmacology , Antioxidants/metabolism , Bixaceae/chemistry , Bixaceae/metabolism , Biological Products/pharmacology , Biological Products/metabolism , Molecular Structure , Carotenoids , Anti-Inflammatory Agents/pharmacology , Anti-Inflammatory Agents/metabolism , Plants, Medicinal/metabolism , Plant Extracts/pharmacology , Plant Extracts/metabolism
9.
Mol Neurobiol ; 60(9): 5155-5166, 2023 Sep.
Article in English | MEDLINE | ID: mdl-37266762

ABSTRACT

Tau is a microtubule-associated binding protein in the nervous system that is known for its role in stabilizing microtubules throughout the nerve cell. It accumulates as ß-sheet-rich aggregates and neurofibrillary tangles, leading to an array of different pathologies. Six splice variants of this protein, generated from the microtubule-associated protein tau (MAPT) gene, are expressed in the brain. Amongst these variants, 0N3R, is prominent during fetal development, while the rest, 0N4R, 1N3R, 1N4R, 2N3R, and 2N4R, are expressed in postnatal stages. Tau isoforms play their role separately or in combination with others to contribute to one or multiple neurodegenerative disorders and clinical syndromes. For instance, in Alzheimer's disease and a subset of frontotemporal lobar degeneration (FTLD)-MAPT (i.e., R406W and V337M), both 3R and 4R isoforms are involved; therefore, they are called 3R/4R mix tauopathies. On the other hand, 4R isoforms are aggregated in progressive supranuclear palsy (PSP), corticobasal degeneration (CBD), and a majority of FTLD-MAPT and these diseases are called 4R tauopathies. Similarly, Pick's disease has an association with 3R tau isoforms and is thereby referred to as 3R tauopathy. Unlike 3R isoforms, the 4R variants have a faster rate of aggregation that accelerates the associated neurodegenerative mechanisms. Moreover, post-translational modifications of each isoform occur at a different rate and dictate their physiological and pathological attributes. The smallest tau isoform (0N3R) is highly phosphorylated in the fetal brain but does not lead to the generation of aggregates. On the other hand, proteoforms in the adult human brain undergo aggregation upon their phosphorylation and glycation. Expanding on this knowledge, this article aims to review the physiological and pathological roles of tau isoforms and their underlying mechanisms that result in neurological deficits. Physiological and pathological relevance of microtubule-associated protein tau (MAPT): Tau exists as six splice variants in the brain, each differing with respect to expression, post-translational modifications (PTMs), and aggregation kinetics. Physiologically, they are involved in the stabilization of microtubules that form the molecular highways for axonal transport. However, an imbalance in their expression and the associated PTMs leads to a disruption in their physiological function through the formation of neurofibrillary tangles that accumulate in various regions of the brain and contribute to several types of tauopathies.


Subject(s)
Alzheimer Disease , Frontotemporal Dementia , Frontotemporal Lobar Degeneration , Tauopathies , Adult , Humans , tau Proteins/metabolism , Tauopathies/metabolism , Alzheimer Disease/pathology , Neurofibrillary Tangles/metabolism , Frontotemporal Lobar Degeneration/pathology , Protein Isoforms/genetics , Protein Isoforms/metabolism , Frontotemporal Dementia/pathology
10.
Molecules ; 28(8)2023 Apr 14.
Article in English | MEDLINE | ID: mdl-37110702

ABSTRACT

As is well known, plant products have been increasingly utilized in the pharmaceutical industry in recent years. By combining conventional techniques and modern methodology, the future of phytomedicines appears promising. Pogostemon Cablin (patchouli) is an important herb used frequently in the fragrance industries and has various therapeutic benefits. Traditional medicine has long used the essential oil of patchouli (P. cablin) as a flavoring agent recognized by the FDA. This is a gold mine for battling pathogens in China and India. In recent years, this plant has seen a significant surge in use, and approximately 90% of the world's patchouli oil is produced by Indonesia. In traditional therapies, it is used for the treatment of colds, fever, vomiting, headaches, and stomachaches. Patchouli oil is used in curing many diseases and in aromatherapy to treat depression and stress, soothe nerves, regulate appetite, and enhance sexual attraction. More than 140 substances, including alcohols, terpenoids, flavonoids, organic acids, phytosterols, lignins, aldehydes, alkaloids, and glycosides, have been identified in P. cablin. Pachypodol (C18H16O7) is an important bioactive compound found in P. cablin. Pachypodol (C18H16O7) and many other biologically essential chemicals have been separated from the leaves of P. cablin and many other medicinally significant plants using repeated column chromatography on silica gel. Pachypodol's bioactive potential has been shown by a variety of assays and methodologies. It has been found to have a number of biological activities, including anti-inflammatory, antioxidant, anti-mutagenic, antimicrobial, antidepressant, anticancer, antiemetic, antiviral, and cytotoxic ones. The current study, which is based on the currently available scientific literature, intends to close the knowledge gap regarding the pharmacological effects of patchouli essential oil and pachypodol, a key bioactive molecule found in this plant.


Subject(s)
Oils, Volatile , Plants, Medicinal , Pogostemon , Quercetin , Oils, Volatile/pharmacology , Oils, Volatile/chemistry
11.
Transl Neurodegener ; 12(1): 12, 2023 03 14.
Article in English | MEDLINE | ID: mdl-36915212

ABSTRACT

α-Synucleinopathies, such as Parkinson's disease (PD), dementia with Lewy bodies (DLB) and multiple system atrophy, are a class of neurodegenerative diseases exhibiting intracellular inclusions of misfolded α-synuclein (αSyn), referred to as Lewy bodies or oligodendroglial cytoplasmic inclusions (Papp-Lantos bodies). Even though the specific cellular distribution of aggregated αSyn differs in PD and DLB patients, both groups show a significant pathological overlap, raising the discussion of whether PD and DLB are the same or different diseases. Besides clinical investigation, we will focus in addition on methodologies, such as protein seeding assays (real-time quaking-induced conversion), to discriminate between different types of α-synucleinopathies. This approach relies on the seeding conversion properties of misfolded αSyn, supporting the hypothesis that different conformers of misfolded αSyn may occur in different types of α-synucleinopathies. Understanding the pathological processes influencing the disease progression and phenotype, provoked by different αSyn conformers, will be important for a personalized medical treatment in future.


Subject(s)
Multiple System Atrophy , Parkinson Disease , Synucleinopathies , Humans , alpha-Synuclein/genetics , alpha-Synuclein/metabolism , Synucleinopathies/diagnosis , Synucleinopathies/genetics , Synucleinopathies/metabolism , Parkinson Disease/diagnosis , Parkinson Disease/genetics , Parkinson Disease/metabolism , Lewy Bodies/pathology , Multiple System Atrophy/diagnosis , Multiple System Atrophy/genetics , Multiple System Atrophy/pathology
12.
Int J Mol Sci ; 23(22)2022 Nov 16.
Article in English | MEDLINE | ID: mdl-36430645

ABSTRACT

ß-glucocerebrosidase (GBA)-associated mutations are a significant risk factor for Parkinson's disease (PD) that aggravate the disease pathology by upregulating the deposition of α-Synuclein (α-Syn). The resultant clinical profile varies for PD patients without GBA mutations. The current study aimed to identify the proteomic targets involved in the pathogenic pathways leading to the differential clinical presentation of GBA-associated PD. CSF samples (n = 32) were obtained from PD patients with GBA mutations (n = 22), PD patients without GBA mutations (n = 7), and healthy controls that were carriers of GBA mutations (n = 3). All samples were subjected to in-gel tryptic digestion followed by the construction of the spectral library and quantitative SWATH-based analysis. CSF α-Syn levels were reduced in both PDIdiopathic and PDGBA cases. Our SWATH-based mass spectrometric analysis detected 363 proteins involved in immune response, stress response, and cell signaling in various groups. Intergroup analysis showed that 52 proteins were significantly up- or downregulated in various groups. Of these 52 targets, 20 proteins were significantly altered in PDGBA cases only while 2 showed different levels in PDIdiopathic patients. Our results show that the levels of several pathologically relevant proteins, including Contactin-1, Selenium-binding protein 1, Adhesion G Protein-Coupled Receptor, and Apolipoprotein E are significantly different among the sporadic and genetic variants of PD and hint at aggravated synaptic damage, oxidative stress, neuronal loss, and aggregation of α-Syn in PDGBA cases.


Subject(s)
Glucosylceramidase , Parkinson Disease , Humans , Glucosylceramidase/genetics , Glucosylceramidase/metabolism , Mass Spectrometry , Parkinson Disease/genetics , Parkinson Disease/metabolism , Proteome , Proteomics , Cerebrospinal Fluid/chemistry , Cerebrospinal Fluid/metabolism
13.
Sensors (Basel) ; 22(19)2022 Sep 28.
Article in English | MEDLINE | ID: mdl-36236466

ABSTRACT

An automotive supply chain includes a range of activities from the concept of the product to its final transfer to a customer and subsequent vehicle maintenance. The three distinct stages of this chain are production, sales, and maintenance. In many countries, automobile records are not available to the public and anyone who has access to the central database or government systems can tamper with these records. In addition, used vehicle maintenance and transfer histories remain unavailable or inaccessible. These issues can be overcome by incorporating state-of-the-art blockchain technology into automotive supply chain management. Blockchain technology uses a chain of blocks for distributed transfer and storage of information, creating a decentralized data register that makes records of any digital asset tamper-proof and transparent. In this paper, we implement a permissioned blockchain-based framework for secure and efficient supply chain management of the automobile industry. We employed Hyperledger Fabric; an enterprise-grade distributed ledger platform for developing solutions. In our solution, the blockchain is customized and private in order to ensure system security. We evaluated our system in terms of memory cost, monetary cost, and speed of execution. Our results demonstrate that only 346 MB of extra memory space is required for storing the automotive data of 1 million users, thus rendering the memory cost negligible. The monetary cost is insignificant as all open source blockchain resources are employed, and the speed of record update is also fast. Our results also show that the decentralization of the automotive supply chain using blockchain can implement system security with minor modifications in the established configuration of the web application database.

14.
Sensors (Basel) ; 22(19)2022 Oct 07.
Article in English | MEDLINE | ID: mdl-36236701

ABSTRACT

Network Function Virtualization (NFV) offers an alternate method to design, deploy and manage network services. The NFV decouples network functions from the dedicated hardware and moves them to the virtual servers so that they can run in the software. One of the major strengths of the NFV is its ability to dynamically extend or reduce resources allocated to Virtual Network Functions (VNF) as needed and at run-time. There is a need for a comprehensive metering component in the cloud to store and process the metrics/samples for efficient auto-scaling or load-management of the VNF. In this paper, we propose an integrating framework for efficient auto-scaling of VNF using Gnocchi; a time-series database that is integrated within the framework to store, handle and index the time-series data. The objective of this study is to validate the efficacy of employing Gnocchi for auto-scaling of VNF, in terms of aggregated data points, database size, data recovery speed, and memory consumption. The employed methodology is to perform a detailed empirical analysis of the proposed framework by deploying a fully functional cloud to implement NFV architecture using several OpenStack components including Gnocchi. Our results show a significant improvement over the legacy Ceilometer configuration in terms of lower metering storage size, less memory utilization in processing and management of metrics, and reduced time delay in retrieving the monitoring data to evaluate alarms for the auto-scaling of VNF.


Subject(s)
Computers , Software
15.
Mov Disord ; 37(1): 39-51, 2022 01.
Article in English | MEDLINE | ID: mdl-34448510

ABSTRACT

BACKGROUND: The cellular prion protein (PrPC ) is a membrane-bound, multifunctional protein mainly expressed in neuronal tissues. Recent studies indicate that the native trafficking of PrPC can be misused to internalize misfolded amyloid beta and α-synuclein (aSyn) oligomers. OBJECTIVES: We define PrPC 's role in internalizing misfolded aSyn in α-synucleinopathies and identify further involved proteins. METHODS: We performed comprehensive behavioral studies on four transgenic mouse models (ThySyn and ThySynPrP00, TgM83 and TgMPrP00) at different ages. We developed PrPC -(over)-expressing cell models (cell line and primary cortical neurons), used confocal laser microscopy to perform colocalization studies, applied mass spectrometry to identify interactomes, and determined disassociation constants using surface plasmon resonance (SPR) spectroscopy. RESULTS: Behavioral deficits (memory, anxiety, locomotion, etc.), reduced lifespans, and higher oligomeric aSyn levels were observed in PrPC -expressing mice (ThySyn and TgM83), but not in homologous Prnp ablated mice (ThySynPrP00 and TgMPrP00). PrPC colocalized with and facilitated aSyn (oligomeric and monomeric) internalization in our cell-based models. Glimepiride treatment of PrPC -overexpressing cells reduced aSyn internalization in a dose-dependent manner. SPR analysis showed that the binding affinity of PrPC to monomeric aSyn was lower than to oligomeric aSyn. Mass spectrometry-based proteomic studies identified clathrin in the immunoprecipitates of PrPC and aSyn. SPR was used to show that clathrin binds to recombinant PrP, but not aSyn. Experimental disruption of clathrin-coated vesicles significantly decreased aSyn internalization. CONCLUSION: PrPC 's native trafficking can be misused to internalize misfolded aSyn through a clathrin-based mechanism, which may facilitate the spreading of pathological aSyn. Disruption of aSyn-PrPC binding is, therefore, an appealing therapeutic target in α-synucleinopathies. © 2021 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.


Subject(s)
Synucleinopathies , alpha-Synuclein , Amyloid beta-Peptides , Animals , Mice , Prion Proteins , Proteomics , alpha-Synuclein/metabolism
16.
Mol Neurobiol ; 59(1): 17-34, 2022 Jan.
Article in English | MEDLINE | ID: mdl-34618331

ABSTRACT

The molecular determinants of atypical clinical variants of Alzheimer's disease, including the recently discovered rapidly progressive Alzheimer's disease (rpAD), are unknown to date. Fibrilization of the amyloid-ß (Aß) peptide is the most frequently studied candidate in this context. The Aß peptide can exist as multiple proteoforms that vary in their post-translational processing, amyloidogenesis, and toxicity. The current study was designed to identify these variations in Alzheimer's disease patients exhibiting classical (sAD) and rapid progression, with the primary aim of establishing if these variants may constitute strains that underlie the phenotypic variability of Alzheimer's disease. We employed two-dimensional polyacrylamide gel electrophoresis and MALDI-ToF mass spectrometry to validate and identify the Aß proteoforms extracted from targeted brain tissues. The biophysical analysis was conducted using RT-QuIC assay, confocal microscopy, and atomic force microscopy. Interactome analysis was performed by co-immunoprecipitation. We present a signature of 33 distinct pathophysiological proteoforms, including the commonly targeted Aß40, Aß42, Aß4-42, Aß11-42, and provide insight into their synthesis and quantities. Furthermore, we have validated the presence of highly hydrophobic Aß seeds in rpAD brains that seeded reactions at a slower pace in comparison to typical Alzheimer's disease. In vitro and in vivo analyses also verified variations in the molecular pathways modulated by brain-derived Aß. These variations in the presence, synthesis, folding, and interactions of Aß among sAD and rpAD brains constitute important points of intervention. Further validation of reported targets and mechanisms will aid in the diagnosis of and therapy for Alzheimer's disease.


Subject(s)
Alzheimer Disease/metabolism , Amyloid beta-Peptides/metabolism , Brain/metabolism , Plaque, Amyloid/metabolism , Aged , Aged, 80 and over , Alzheimer Disease/pathology , Brain/pathology , Disease Progression , Female , Humans , Male , Middle Aged , Plaque, Amyloid/pathology , Proteomics , Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
17.
Commun Biol ; 4(1): 411, 2021 03 25.
Article in English | MEDLINE | ID: mdl-33767334

ABSTRACT

Prion diseases are distinguished by long pre-clinical incubation periods during which prions actively propagate in the brain and cause neurodegeneration. In the pre-clinical stage, we hypothesize that upon prion infection, transcriptional changes occur that can lead to early neurodegeneration. A longitudinal analysis of miRNAs in pre-clinical and clinical forms of murine prion disease demonstrated dynamic expression changes during disease progression in the affected thalamus region and serum. Serum samples at each timepoint were collected whereby extracellular vesicles (EVs) were isolated and used to identify blood-based biomarkers reflective of pathology in the brain. Differentially expressed EV miRNAs were validated in human clinical samples from patients with human sporadic Creutzfeldt-Jakob disease (sCJD), with the molecular subtype at codon 129 either methionine-methionine (MM, n = 14) or valine-valine (VV, n = 12) compared to controls (n = 20). EV miRNA biomarkers associated with prion infection predicted sCJD with an AUC of 0.800 (85% sensitivity and 66.7% specificity) in a second independent validation cohort (n = 26) of sCJD and control patients with MM or VV subtype. This study discovered clinically relevant miRNAs that benefit diagnostic development to detect prion-related diseases and therapeutic development to inhibit prion infectivity.


Subject(s)
Brain/pathology , MicroRNAs/analysis , Prion Diseases/etiology , Aged , Aged, 80 and over , Animals , Biomarkers/blood , Creutzfeldt-Jakob Syndrome/blood , Creutzfeldt-Jakob Syndrome/etiology , Female , Humans , Male , Mice , Mice, Inbred BALB C , MicroRNAs/blood , Middle Aged , Prion Diseases/blood
18.
Mol Neurodegener ; 16(1): 11, 2021 02 22.
Article in English | MEDLINE | ID: mdl-33618749

ABSTRACT

BACKGROUND: High-density oligomers of the prion protein (HDPs) have previously been identified in brain tissues of patients with rapidly progressive Alzheimer's disease (rpAD). The current investigation aims at identifying interacting partners of HDPs in the rpAD brains to unravel the pathological involvement of HDPs in the rapid progression. METHODS: HDPs from the frontal cortex tissues of rpAD brains were isolated using sucrose density gradient centrifugation. Proteins interacting with HDPs were identified by co-immunoprecipitation coupled with mass spectrometry. Further verifications were carried out using proteomic tools, immunoblotting, and confocal laser scanning microscopy. RESULTS: We identified rpAD-specific HDP-interactors, including the growth arrest specific 2-like 2 protein (G2L2). Intriguingly, rpAD-specific disturbances were found in the localization of G2L2 and its associated proteins i.e., the end binding protein 1, α-tubulin, and ß-actin. DISCUSSION: The results show the involvement of HDPs in the destabilization of the neuronal actin/tubulin infrastructure. We consider this disturbance to be a contributing factor for the rapid progression in rpAD.


Subject(s)
Alzheimer Disease/metabolism , Brain/metabolism , Cytoskeleton/metabolism , Prion Proteins/metabolism , Amyloid beta-Peptides/metabolism , Cytoskeleton/pathology , Disease Progression , Humans , Neurons/metabolism
19.
Int J Mol Sci ; 22(3)2021 Jan 22.
Article in English | MEDLINE | ID: mdl-33499319

ABSTRACT

Proteinopathy refers to a group of disorders defined by depositions of amyloids within living tissue. Neurodegenerative proteinopathies, including Alzheimer's disease, Parkinson's disease, Creutzfeldt-Jakob disease, and others, constitute a large fraction of these disorders. Amyloids are highly insoluble, ordered, stable, beta-sheet rich proteins. The emerging theory about the pathophysiology of neurodegenerative proteinopathies suggests that the primary amyloid-forming proteins, also known as the prion-like proteins, may exist as multiple proteoforms that contribute differentially towards the disease prognosis. It is therefore necessary to resolve these disorders on the level of proteoforms rather than the proteome. The transient and hydrophobic nature of amyloid-forming proteins and the minor post-translational alterations that lead to the formation of proteoforms require the use of highly sensitive and specialized techniques. Several conventional techniques, like gel electrophoresis and conventional mass spectrometry, have been modified to accommodate the proteoform theory and prion-like proteins. Several new ones, like imaging mass spectrometry, have also emerged. This review aims to discuss the proteoform theory of neurodegenerative disorders along with the utility of these proteomic techniques for the study of highly insoluble proteins and their associated proteoforms.


Subject(s)
Amyloid/chemistry , Neurodegenerative Diseases/diagnosis , Neurodegenerative Diseases/metabolism , Prion Proteins/chemistry , Adult , Age of Onset , Aged , Electrophoresis, Gel, Two-Dimensional , Humans , Mass Spectrometry , Middle Aged , Prognosis , Protein Folding , Protein Processing, Post-Translational , Proteome , Proteomics , Software , Spectrometry, Mass, Electrospray Ionization , Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
20.
Front Bioeng Biotechnol ; 8: 586890, 2020.
Article in English | MEDLINE | ID: mdl-33330419

ABSTRACT

The real-time quaking-induced conversion (RT-QuIC) assay is a highly reproducible and robust methodology exhibiting an excellent pre-mortem diagnostic accuracy for prion diseases. However, the protocols might be time-consuming and improvement of the detection technology is needed. In the present study, we investigated the influence of a pre-analytical cerebrospinal fluid (CSF) treatment with proteinase K (PK) on the kinetic of the RT-QuIC signal response. For this purpose, we added PK at different concentrations in RT-QuIC reactions seeded with Creutzfeldt-Jakob disease (sCJD) CSF. We observed that a mild pre-analytical PK treatment of CSF samples resulted in an increased seeding efficiency of the RT-QuIC reaction. Quantitative seeding parameters, such as a higher area under the curve (AUC) value or a shorter lag phase indicated a higher conversion efficiency after treatment. The diagnostic accuracy resulting from 2 µg/ml PK treatment was analyzed in a retrospective study, where we obtained a sensitivity of 89%. Additionally, we analyzed the agreement with the previously established standard RT-QuIC protocol without PK treatment in a prospective study. Here, we found an overall agreement of 94% to 96%. A Cohen's kappa of 0.9036 (95% CI: 0.8114-0.9958) indicates an almost perfect agreement between both protocols. In conclusion, the outcome of our study can be used for a further optimization of the RT-QuIC assay in particular for a reduction of the testing time.

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