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  1. Article ; Online: C9orf72-associated dipeptide protein repeats form A11-positive oligomers in amyotrophic lateral sclerosis and frontotemporal dementia.

    Bhatt, Nemil / Puangmalai, Nicha / Sengupta, Urmi / Jerez, Cynthia / Kidd, Madison / Gandhi, Shailee / Kayed, Rakez

    The Journal of biological chemistry

    2024  Volume 300, Issue 2, Page(s) 105628

    Abstract: Hexanucleotide repeat expansion in C9orf72 is one of the most common causes of amyotrophic lateral sclerosis and frontotemporal dementia. The hexanucleotide expansion, formed by GGGGCC (G4C2) repeats, leads to the production of five dipeptide protein ... ...

    Abstract Hexanucleotide repeat expansion in C9orf72 is one of the most common causes of amyotrophic lateral sclerosis and frontotemporal dementia. The hexanucleotide expansion, formed by GGGGCC (G4C2) repeats, leads to the production of five dipeptide protein repeats (DPRs) via repeat-associated non-AUG translation. Among the five dipeptide repeats, Gly-Arg, Pro-Arg, and Gly-Ala form neuronal inclusions that contain aggregates of the peptides. Several studies have attempted to model DPR-associated toxicity using various repeat lengths, which suggests a unique conformation that is cytotoxic and is independent of the repeat length. However, the structural characteristics of DPR aggregates have yet to be determined. Increasing evidence suggests that soluble species, such as oligomers, are the main cause of toxicity in proteinopathies, such as Alzheimer's and Parkinson's disease. To investigate the ability of DPRs to aggregate and form toxic oligomers, we adopted a reductionist approach using small dipeptide repeats of 3, 6, and 12. This study shows that DPRs, particularly glycine-arginine and proline-arginine, form oligomers that exhibit distinct dye-binding properties and morphologies. Importantly, we also identified toxic DPR oligomers in amyotrophic lateral sclerosis and frontotemporal dementia postmortem brains that are morphologically similar to those generated recombinantly. This study demonstrates that, similar to soluble oligomers formed by various amyloid proteins, DPR oligomers are toxic, independent of their repeat length.
    MeSH term(s) Humans ; Frontotemporal Dementia/genetics ; Amyotrophic Lateral Sclerosis/genetics ; Amyotrophic Lateral Sclerosis/metabolism ; C9orf72 Protein/genetics ; C9orf72 Protein/metabolism ; DNA Repeat Expansion ; Dipeptides/chemistry ; Arginine ; Amyloidogenic Proteins ; Glycine
    Chemical Substances C9orf72 Protein ; Dipeptides ; Arginine (94ZLA3W45F) ; Amyloidogenic Proteins ; Glycine (TE7660XO1C) ; C9orf72 protein, human
    Language English
    Publishing date 2024-01-10
    Publishing country United States
    Document type Journal Article
    ZDB-ID 2997-x
    ISSN 1083-351X ; 0021-9258
    ISSN (online) 1083-351X
    ISSN 0021-9258
    DOI 10.1016/j.jbc.2024.105628
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  2. Article ; Online: Traumatic brain injury derived pathological tau polymorphs induce the distinct propagation pattern and neuroinflammatory response in wild type mice.

    Puangmalai, Nicha / Bhatt, Nemil / Bittar, Alice / Jerez, Cynthia / Shchankin, Nikita / Kayed, Rakez

    Progress in neurobiology

    2023  Volume 232, Page(s) 102562

    Abstract: The misfolding and aggregation of the tau protein into neurofibrillary tangles constitutes a central feature of tauopathies. Traumatic brain injury (TBI) has emerged as a potential risk factor, triggering the onset and progression of tauopathies. Our ... ...

    Abstract The misfolding and aggregation of the tau protein into neurofibrillary tangles constitutes a central feature of tauopathies. Traumatic brain injury (TBI) has emerged as a potential risk factor, triggering the onset and progression of tauopathies. Our previous research revealed distinct polymorphisms in soluble tau oligomers originating from single versus repetitive mild TBIs. However, the mechanisms orchestrating the dissemination of TBI brain-derived tau polymorphs (TBI-BDTPs) remain elusive. In this study, we explored whether TBI-BDTPs could initiate pathological tau formation, leading to distinct pathogenic trajectories. Wild-type mice were exposed to TBI-BDTPs from sham, single-blast (SB), or repeated-blast (RB) conditions, and their memory function was assessed through behavioral assays at 2- and 8-month post-injection. Our findings revealed that RB-BDTPs induced cognitive and motor deficits, concurrently fostering the emergence of toxic tau aggregates within the injected hippocampus. Strikingly, this tau pathology propagated to cortical layers, intensifying over time. Importantly, RB-BDTP-exposed animals displayed heightened glial cell activation, NLRP3 inflammasome formation, and increased TBI biomarkers, particularly triggering the aggregation of S100B, which is indicative of a neuroinflammatory response. Collectively, our results shed light on the intricate mechanisms underlying TBI-BDTP-induced tau pathology and its association with neuroinflammatory processes. This investigation enhances our understanding of tauopathies and their interplay with neurodegenerative and inflammatory pathways following traumatic brain injury.
    MeSH term(s) Mice ; Animals ; tau Proteins/metabolism ; Brain Injuries, Traumatic/complications ; Tauopathies/metabolism ; Neurofibrillary Tangles/metabolism ; Inflammation/complications ; Disease Models, Animal
    Chemical Substances tau Proteins
    Language English
    Publishing date 2023-12-21
    Publishing country England
    Document type Journal Article
    ZDB-ID 185535-9
    ISSN 1873-5118 ; 0301-0082
    ISSN (online) 1873-5118
    ISSN 0301-0082
    DOI 10.1016/j.pneurobio.2023.102562
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  3. Article ; Online: In pursuit of degenerative brain disease diagnosis: Dementia biomarkers detected by DNA aptamer-attached portable graphene biosensor.

    Bodily, Tyler Andrew / Ramanathan, Anirudh / Wei, Shanhong / Karkisaval, Abhijith / Bhatt, Nemil / Jerez, Cynthia / Haque, Md Anzarul / Ramil, Armando / Heda, Prachi / Wang, Yi / Kumar, Sanjeev / Leite, Mikayla / Li, Tie / Zhao, Jianlong / Lal, Ratnesh

    Proceedings of the National Academy of Sciences of the United States of America

    2023  Volume 120, Issue 47, Page(s) e2311565120

    Abstract: Dementia is a brain disease which results in irreversible and progressive loss of cognition and motor activity. Despite global efforts, there is no simple and reliable diagnosis or treatment option. Current diagnosis involves indirect testing of commonly ...

    Abstract Dementia is a brain disease which results in irreversible and progressive loss of cognition and motor activity. Despite global efforts, there is no simple and reliable diagnosis or treatment option. Current diagnosis involves indirect testing of commonly inaccessible biofluids and low-resolution brain imaging. We have developed a portable, wireless readout-based Graphene field-effect transistor (GFET) biosensor platform that can detect viruses, proteins, and small molecules with single-molecule sensitivity and specificity. We report the detection of three important amyloids, namely, Amyloid beta (Aβ), Tau (τ), and α-Synuclein (αS) using DNA aptamer nanoprobes. These amyloids were isolated, purified, and characterized from the autopsied brain tissues of Alzheimer's Disease (AD) and Parkinson's Disease (PD) patients. The limit of detection (LoD) of the sensor is 10 fM, 1-10 pM, 10-100 fM for Aβ, τ, and αS, respectively. Synthetic as well as autopsied brain-derived amyloids showed a statistically significant sensor response with respect to derived thresholds, confirming the ability to define diseased vs. nondiseased states. The detection of each amyloid was specific to their aptamers; Aβ, τ, and αS peptides when tested, respectively, with aptamers nonspecific to them showed statistically insignificant cross-reactivity. Thus, the aptamer-based GFET biosensor has high sensitivity and precision across a range of epidemiologically significant AD and PD variants. This portable diagnostic system would allow at-home and POC testing for neurodegenerative diseases globally.
    MeSH term(s) Humans ; Amyloid beta-Peptides/metabolism ; Aptamers, Nucleotide ; Graphite ; Alzheimer Disease/diagnosis ; Alzheimer Disease/metabolism ; Parkinson Disease/diagnosis ; Biomarkers ; tau Proteins
    Chemical Substances Amyloid beta-Peptides ; Aptamers, Nucleotide ; Graphite (7782-42-5) ; Biomarkers ; tau Proteins
    Language English
    Publishing date 2023-11-13
    Publishing country United States
    Document type Journal Article
    ZDB-ID 209104-5
    ISSN 1091-6490 ; 0027-8424
    ISSN (online) 1091-6490
    ISSN 0027-8424
    DOI 10.1073/pnas.2311565120
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  4. Article: Central and peripheral tau retention modulated by an anti-tau antibody.

    Solorzano, Alexander / Brady, Molly / Bhatt, Nemil / Johnson, Angelique / Burgess, Brooke / Leyva, Hannah / Puangmalai, Nicha / Jerez, Cynthia / Wood, Ronald / Kayed, Rakez / Deane, Rashid

    bioRxiv : the preprint server for biology

    2023  

    Abstract: Tau protein blood levels dependent on its distribution to peripheral organs and possible elimination from the body. Thus, the peripheral distribution of CSF-derived tau protein was explored, especially since there is a transition to blood-based ... ...

    Abstract Tau protein blood levels dependent on its distribution to peripheral organs and possible elimination from the body. Thus, the peripheral distribution of CSF-derived tau protein was explored, especially since there is a transition to blood-based biomarkers and the emerging idea that tau pathology may spread beyond brain. Near infrared fluorescence (NIRF) was mainly used to analyze tau (tau-NIRF) distribution after its intracisternal or intravenous injection. There was a striking uptake of blood- or CSF-derived tau-NIRF protein by the skeletal structures, liver, small intestine (duodenum), gall bladder, kidneys, urinary bladder, lymph nodes, heart, and spleen. In aging and in older APP/PS1 mice, tau uptake in regions, such as the brain, liver, and skeleton, was increased. In bone (femur) injected tau protein was associated with integrin-binding sialoprotein (IBSP), a major non-collagenous glycoprotein that is associated with mineralization. Tau-NIRF was cleared slowly from CSF via mainly across the cribriform plate, and cervical lymph nodes. In brain, some of the CSF injected tau protein was associated with NeuN-positive and PDGFRý-positive cells, which may explain its retention. The presence of tau in the bladders suggested excretion routes of tau. CSF anti-tau antibody increased CSF tau clearance, while blood anti-tau antibody decreased tau accumulation in the femur but not in liver, kidney, and spleen. Thus, the data show a body-wide distribution and retention of CSF-derived tau protein, which increased with aging and in older APP/PS1 mice. Further work is needed to elucidate the relevance of tau accumulation in each organ to tauopathy.
    Language English
    Publishing date 2023-08-18
    Publishing country United States
    Document type Preprint
    DOI 10.1101/2023.08.17.553682
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  5. Article ; Online: Lysine 63-linked ubiquitination of tau oligomers contributes to the pathogenesis of Alzheimer's disease.

    Puangmalai, Nicha / Sengupta, Urmi / Bhatt, Nemil / Gaikwad, Sagar / Montalbano, Mauro / Bhuyan, Arijit / Garcia, Stephanie / McAllen, Salome / Sonawane, Minal / Jerez, Cynthia / Zhao, Yingxin / Kayed, Rakez

    The Journal of biological chemistry

    2022  Volume 298, Issue 4, Page(s) 101766

    Abstract: Ubiquitin-modified tau aggregates are abundantly found in human brains diagnosed with Alzheimer's disease (AD) and other tauopathies. Soluble tau oligomers (TauO) are the most neurotoxic tau species that propagate pathology and elicit cognitive deficits, ...

    Abstract Ubiquitin-modified tau aggregates are abundantly found in human brains diagnosed with Alzheimer's disease (AD) and other tauopathies. Soluble tau oligomers (TauO) are the most neurotoxic tau species that propagate pathology and elicit cognitive deficits, but whether ubiquitination contributes to tau formation and spreading is not fully understood. Here, we observed that K63-linked, but not K48-linked, ubiquitinated TauO accumulated at higher levels in AD brains compared with age-matched controls. Using mass spectrometry analyses, we identified 11 ubiquitinated sites on AD brain-derived TauO (AD TauO). We found that K63-linked TauO are associated with enhanced seeding activity and propagation in human tau-expressing primary neuronal and tau biosensor cells. Additionally, exposure of tau-inducible HEK cells to AD TauO with different ubiquitin linkages (wild type, K48, and K63) resulted in enhanced formation and secretion of K63-linked TauO, which was associated with impaired proteasome and lysosome functions. Multipathway analysis also revealed the involvement of K63-linked TauO in cell survival pathways, which are impaired in AD. Collectively, our study highlights the significance of selective TauO ubiquitination, which could influence tau aggregation, accumulation, and subsequent pathological propagation. The insights gained from this study hold great promise for targeted therapeutic intervention in AD and related tauopathies.
    MeSH term(s) Alzheimer Disease/physiopathology ; Cells, Cultured ; Humans ; Lysine/metabolism ; Neurons/pathology ; Tauopathies/physiopathology ; Ubiquitin/metabolism ; Ubiquitination ; tau Proteins/metabolism
    Chemical Substances Ubiquitin ; tau Proteins ; Lysine (K3Z4F929H6)
    Language English
    Publishing date 2022-02-22
    Publishing country United States
    Document type Journal Article
    ZDB-ID 2997-x
    ISSN 1083-351X ; 0021-9258
    ISSN (online) 1083-351X
    ISSN 0021-9258
    DOI 10.1016/j.jbc.2022.101766
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  6. Article ; Online: Passive Immunotherapy Targeting Tau Oligomeric Strains Reverses Tauopathy Phenotypes in Aged Human-Tau Mice in a Mouse Model-Specific Manner.

    Bittar, Alice / Al-Lahham, Rabab / Bhatt, Nemil / Moore, Kenya / Montalbano, Mauro / Jerez, Cynthia / Fung, Leiana / McAllen, Salome / Ellsworth, Anna / Kayed, Rakez

    Journal of Alzheimer's disease : JAD

    2022  Volume 90, Issue 3, Page(s) 1103–1122

    Abstract: Background: Tau oligomers are one of the most toxic species, displaying prion-like strains which have different conformations resulting in different tauopathies. Passive immunotherapy targeting different tau species is a promising therapeutic approach. ... ...

    Abstract Background: Tau oligomers are one of the most toxic species, displaying prion-like strains which have different conformations resulting in different tauopathies. Passive immunotherapy targeting different tau species is a promising therapeutic approach. Age is one of the greatest risk factors; however, most immunotherapy studies are done in young to middle-aged mice tauopathy models, which is not representative of the many clinical trials done with older humans with established tauopathies.
    Objective: We utilized two different clones of tau oligomer monoclonal antibodies (TOMAs) in aged Htau and JNPL3 mouse models to investigate the potential of passive immunotherapy.
    Methods: Aged mice received a single intravenous injection of 120 μg/animal of either TOMA1, TOMA3 clones or a non-specific IgG. Their cognitive functions were assessed one-week post-injection using Y-maze and novel object recognition tests. Brain tissues were analyzed using biochemical and immunological assays.
    Results: TOMA 1 and 3 rescues cognitive phenotypes in aged animals in a mouse model-specific manner, indicative by a reduction in tau oligomers levels. The TOMAs were shown to have strong reactivity with different tau oligomeric species in the different mouse models in vitro and ex vivo.
    Conclusion: This is the first study testing tau passive immunotherapy in aged animals and supports our previous reports on of the role of oligomeric tau in disease progression further validating the potential of TOMAs to rescue the late-stage disease pathology and phenotype. Moreover, this study suggests that multiple tau oligomeric strains exist in aged animals; therefore, it is of great importance to further characterize these strains.
    MeSH term(s) Animals ; Humans ; Mice ; Antibodies, Monoclonal/genetics ; Disease Models, Animal ; Immunization, Passive ; Mice, Transgenic ; Phenotype ; tau Proteins/genetics ; Tauopathies/pathology ; Tauopathies/therapy
    Chemical Substances Antibodies, Monoclonal ; tau Proteins
    Language English
    Publishing date 2022-10-03
    Publishing country Netherlands
    Document type Journal Article
    ZDB-ID 1440127-7
    ISSN 1875-8908 ; 1387-2877
    ISSN (online) 1875-8908
    ISSN 1387-2877
    DOI 10.3233/JAD-220518
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  7. Article: Flow cytometric isolation of drug-like conformational antibodies specific for amyloid fibrils.

    Desai, Alec A / Zupancic, Jennifer M / Trzeciakiewicz, Hanna / Gerson, Julia E / DuBois, Kelly N / Skinner, Mary E / Sharkey, Lisa M / McArthur, Nikki / Ferris, Sean P / Bhatt, Nemil N / Makowski, Emily K / Smith, Matthew D / Chen, Hongwei / Huang, Jie / Jerez, Cynthia / Kane, Ravi S / Kanaan, Nicholas M / Paulson, Henry L / Tessier, Peter M

    bioRxiv : the preprint server for biology

    2023  

    Abstract: Antibodies that recognize specific protein conformational states are broadly important for research, diagnostic and therapeutic applications, yet they are difficult to generate in a predictable and systematic manner using either immunization ... ...

    Abstract Antibodies that recognize specific protein conformational states are broadly important for research, diagnostic and therapeutic applications, yet they are difficult to generate in a predictable and systematic manner using either immunization or
    Language English
    Publishing date 2023-07-04
    Publishing country United States
    Document type Preprint
    DOI 10.1101/2023.07.04.547698
    Database MEDical Literature Analysis and Retrieval System OnLINE

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