Publications by authors named "Dhruva D Dhavale"

Article Synopsis
  • TDP-43 is an RNA binding protein that forms aggregates in the central nervous system and is notably present in certain neurodegenerative diseases and inclusion body myopathy, a type of muscle disease.
  • Researchers developed a mouse model that shows muscle weakness associated with TDP-43 accumulation, which indicates a prion-like spread of the protein possibly affecting muscle tissues.
  • Human muscle biopsies from patients with various conditions, especially inclusion body myositis (IBM), contain TDP-43 aggregate seeds, suggesting a unique pathogenic role for TDP-43 in muscle diseases that wasn't fully recognized before.
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Article Synopsis
  • TDP-43 is an RNA binding protein that, when it aggregates, is linked to both neurodegenerative diseases like ALS and FTD and muscle diseases such as inclusion body myopathy (IBM).
  • Mice engineered to express muscle-specific TDP-43 showed muscle weakness and harmful TDP-43 aggregation, but these issues resolved after doxycycline treatment, indicating an inducible condition.
  • Human muscle samples from IBM patients revealed TDP-43 aggregate seeds that were unique to IBM, suggesting a distinct, previously unrecognized mechanism of TDP-43 pathology in muscle disease.
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Lysosomal membrane permeabilization caused either via phagocytosis of particulates or the uptake of protein aggregates can trigger the activation of NLRP3 inflammasome- an intense inflammatory response that drives the release of the pro-inflammatory cytokine IL-1β by regulating the activity of CASPASE 1. The maintenance of lysosomal homeostasis and lysosomal membrane integrity is facilitated by the AAA+ ATPase, VCP/p97 (VCP). However, the relationship between VCP and NLRP3 inflammasome activity remains unexplored.

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Article Synopsis
  • * The researchers developed a new method to enhance the extraction of these alpha-synuclein fibrils from postmortem tissue, using solid state nuclear magnetic resonance (SSNMR) to analyze their atomic structure.
  • * Their findings reveal that the fibrils from Lewy body dementia consist of both single and double protofilaments, and display structural similarities to previously studied twisted fibrils; this could aid in understanding disease mechanisms and developing new treatments.
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Article Synopsis
  • Fibrils of the protein α-synuclein are linked to several neurodegenerative diseases, including Parkinson's Disease and Lewy Body Dementia.
  • Researchers have utilized solid-state NMR methods to analyze various forms of α-synuclein fibrils and previously published resonance assignments.
  • This study introduces a new set of carbon and nitrogen assignments specific to fibrils derived from the postmortem brain tissue of a Lewy Body Dementia patient.
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Article Synopsis
  • Fibrils of the protein α-synuclein are linked to diseases like Parkinson Disease, Lewy Body Dementia, and Multiple System Atrophy.
  • There has been extensive research on different forms of α-synuclein fibrils using solid-state NMR, with various resonance assignments documented.
  • This study presents new carbon and nitrogen assignments specific to fibrils derived from postmortem brain tissue of a Lewy Body Dementia patient.
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Article Synopsis
  • - The main feature of Parkinson disease (PD) and Lewy body dementia (LBD) is the buildup of alpha-synuclein (Asyn) fibrils in structures known as Lewy bodies and neurites.
  • - A new method was developed to amplify Asyn fibrils from postmortem LBD tissue, allowing researchers to study their atomic structure using solid state nuclear magnetic resonance (SSNMR).
  • - The amplified Asyn fibrils consist of two protofilaments with a specific structural arrangement, showing similarities to a previous study, which provides insights for understanding disease mechanisms and potential treatments targeting Asyn.
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Objective: Parkinson disease (PD) is defined by the accumulation of misfolded α-synuclein (α-syn) in Lewy bodies and Lewy neurites. It affects multiple cortical and subcortical neuronal populations. The majority of people with PD develop dementia, which is associated with Lewy bodies in neocortex and referred to as Lewy body dementia (LBD).

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Apolipoprotein E () ε4 genotype is associated with increased risk of dementia in Parkinson's disease (PD), but the mechanism is not clear, because patients often have a mixture of α-synuclein (αSyn), amyloid-β (Aβ), and tau pathologies. ε4 exacerbates brain Aβ pathology, as well as tau pathology, but it is not clear whether genotype independently regulates αSyn pathology. In this study, we generated A53T αSyn transgenic mice (A53T) on knockout (A53T/EKO) or human knockin backgrounds (A53T/E2, E3, and E4).

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Aggregates of the RNA-binding protein TDP-43 (TAR DNA-binding protein) are a hallmark of the overlapping neurodegenerative disorders amyotrophic lateral sclerosis (ALS) and frontotemporal dementia. The process of TDP-43 aggregation remains poorly understood, and whether it includes formation of intermediate complexes is unknown. Here, we analyzed aggregates derived from purified TDP-43 under semidenaturing conditions, identifying distinct oligomeric complexes at the initial time points before the formation of large aggregates.

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Parkinson's disease (PD) and multiple system atrophy (MSA) are distinct clinical syndromes characterized by the pathological accumulation of α-synuclein (α-syn) protein fibrils in neurons and glial cells. These disorders and other neurodegenerative diseases may progress via prion-like mechanisms. The prion model of propagation predicts the existence of "strains" that link pathological aggregate structure and neuropathology.

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Here we report the synthesis and in vitro evaluation of 25 new quinolinyl analogues for α-synuclein aggregates. Three lead compounds were subsequently labeled with carbon-11 or fluorine-18 to directly assess their potency in a direct radioactive competitive binding assay ng both α-synuclein fibrils and tissue homogenates from Alzheimer's disease (AD) cases. The modest binding affinities of these three radioligands toward α-synuclein were comparable with results from the Thioflavin T fluorescence assay.

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Fibrils of the protein α-synuclein (α-syn) are implicated in the pathogenesis of Parkinson's disease and related neurodegenerative disorders. We have reported a high-resolution structure (PDB 2N0A) of an α-syn fibril form prepared by in vitro incubation of monomeric protein in 50 mM sodium phosphate buffer pH 7.4 with 0.

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The accumulation of α-synuclein (α-syn) fibrils in neuronal inclusions is the defining pathological process in Parkinson's disease (PD). A pathogenic role for α-syn fibril accumulation is supported by the identification of dominantly inherited α-syn () gene mutations in rare cases of familial PD. Fibril formation involves a spontaneous nucleation event in which soluble α-syn monomers associate to form seeds, followed by fibril growth during which monomeric α-syn molecules sequentially associate with existing seeds.

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Fluselenamyl (5), a novel planar benzoselenazole shows traits desirable of enabling noninvasive imaging of Aβ pathophysiology in vivo; labeling of both diffuse (an earlier manifestation of neuritic plaques) and fibrillar plaques in Alzheimer's disease (AD) brain sections, and remarkable specificity for mapping Aβ compared with biomarker proteins of other neurodegenerative diseases. Employing AD homogenates, [F]-9, a PET tracer demonstrates superior (2-10 fold higher) binding affinity than approved FDA tracers, while also indicating binding to high affinity site on Aβ plaques. Pharmacokinetic studies indicate high initial influx of [F]-9 in normal mice brains accompanied by rapid clearance in the absence of targeted plaques.

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