Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 36
Filter
Add more filters










Publication year range
1.
In Vivo ; 38(1): 226-234, 2024.
Article in English | MEDLINE | ID: mdl-38148068

ABSTRACT

BACKGROUND/AIM: Chronic kidney disease (CKD) is one of the most common causes of mortality in wild non-domestic felidae. The molecular mechanism regulating renal fibrosis in nephropathy is not fully understood especially in the felidae. This study aimed to elucidate senescence marker protein 30 (SMP30) expression patterns and its relationship with epithelial-mesenchymal transition (EMT) by immunostaining in two necropsied Siberian tigers (Panthera tigris altaica) with CKD. MATERIALS AND METHODS: Two kidney samples from male Siberian tigers were fixed and tissue sections were stained for histopathological assay. RESULTS: In CKD, renal tubular epithelial cells lost their tubular structures surrounded by severe interstitial fibrosis and were detached from the basement membrane. These damaged cells resembled the morphology of mesenchymal cells and showed much lower SMP30 expression compared with intact tubular epithelial cells. These cells also expressed vimentin, which is specifically expressed by mesenchymal cells, and through double staining, it was observed that vimentin was expressed in the tubular epithelial cells where SMP30 was not expressed. In addition, double-positive expression of pan-cytokeratin (pan-CK) and vimentin was found in damaged epithelial cells with mesenchymal features. CONCLUSION: We demonstrated possible evidence to understand the role of SMP30 as a new pivotal factor and the possibility of decreased SMP30 as a potential indicator of EMT at the end stage of CKD.


Subject(s)
Felidae , Renal Insufficiency, Chronic , Tigers , Animals , Male , Humans , Vimentin , Kidney , Renal Insufficiency, Chronic/genetics , Epithelial-Mesenchymal Transition/genetics , Fibrosis
2.
Mater Today Bio ; 23: 100838, 2023 Dec.
Article in English | MEDLINE | ID: mdl-38033369

ABSTRACT

Polymer-based lab-on-a-disc (LoaD) devices for isolating ribonucleic acid (RNA) from whole blood samples have gained considerable attention for accurate biomedical analysis and point-of-care diagnostics. However, the mass production of these devices remains challenging in manufacturing cost and sustainability, primarily due to the utilization of a laser cutter or router computer numerical control (CNC) machine for engraving and cutting plastics in the conventional prototyping process. Herein, we reported the first energy-efficient room-temperature printing-imprinting integrated roll-to-roll manufacturing platform for mass production of a polydimethylsiloxane (PDMS)-based LoaD to on-site isolate ribonucleic acid (RNA) from undiluted blood samples. We significantly reduced energy consumption and eliminated thermal expansion variations between the mold, substrate, and resists by accelerating the PDMS curing time to less than 10 min at room temperature without using heat or ultraviolet radiation. The additive manufacturing technology was applied to fabricate a multi-depth flexible polymer mold that integrated macro (2 mm) and micro-sized (500 µm) features, which overcomes the economic and environmental challenges of conventional molding techniques. Our integrated R2R platform was enabled to print adhesion-promoting films at the first printing unit and continuously in-line imprint with a high replication accuracy (99%) for high-volume manufacturing of a new centrifugal microfluidic chip with an enhancement of mixing performance by integrating an efficient mixing chamber and serpentine micromixer. This research paved the way for scalable green manufacturing of large-volume polymer-based microfluidic devices, often required in real-world sample-driven analytical systems for clinical bioanalysis.

3.
bioRxiv ; 2023 Sep 14.
Article in English | MEDLINE | ID: mdl-37745332

ABSTRACT

Mutations in the GBA1 gene have been identified as a prevalent genetic risk factor for Parkinson's disease (PD). GBA1 mutations impair enzymatic activity, leading to lysosomal dysfunction and elevated levels of α-synuclein (α-syn). While most research has primarily focused on GBA1's role in promoting synucleinopathy, emerging evidence suggests that neuroinflammation may be a key pathogenic alteration caused by GBA1 deficiency. To examine the molecular mechanism underlying GBA1 deficiency-mediated neuroinflammation, we generated Gba1 E326K knock-in (KI) mice using the CRISPR/Cas9 technology, which is linked to an increased risk of PD and dementia with Lewy bodies (DLB). In the ventral midbrain and hippocampus of 24-month-old Gba1 E326K KI mice, we found a moderate decline in GBA1 enzymatic activity, a buildup of glucosylceramide, and an increase in microglia density. Furthermore, we observed increased levels of pro-inflammatory cytokines and formation of reactive astrocytes in primary microglia and astrocytes, respectively, cultured from Gba1 E326K KI mice following treatment with pathologic α-syn preformed fibrils (PFF). Additionally, the gut inoculation of α-syn PFF in Gba1 E326K KI mice significantly enhanced the accumulation of Lewy bodies in the dentate gyrus of the hippocampus, accompanied by aggravated neuroinflammation and exacerbated non-motor symptoms. This research significantly enhances our understanding of the Gba1 E326K mutation's involvement in neuroinflammation and the cell-to-cell transmission of pathogenic α-syn in the brain, thereby opening new therapeutic avenues.

4.
MRS Commun ; 13(6): 1053-1062, 2023 Dec.
Article in English | MEDLINE | ID: mdl-38818251

ABSTRACT

The ability to govern particle assembly in an evaporative-driven additive manufacturing (AM) can realize multi-scale features fundamental to creating printed electronics. However, existing techniques remain challenging and often require templates or contaminating solutes. We explore the control of particle deposition in 3D-printed colloids by diffusiophoresis, a previously unexplored mechanism in multi-scale AM. Diffusiophoresis can introduce spontaneous phoretic particle motion by establishing local solute concentration gradients. We show that diffusiophoresis can play a dominant role in complex evaporative-driven particle assembly, enabling a fundamentally new and versatile control of particle deposition in a multi-scale AM process.

5.
Cells ; 11(24)2022 12 08.
Article in English | MEDLINE | ID: mdl-36552734

ABSTRACT

Non-receptor tyrosine kinase, c-Abl plays a role in the pathogenesis of several neurodegenerative disorders such as Alzheimer's disease and Parkinson's disease. Here, we found that TDP-43, which was one of the main proteins comprising pathological deposits in amyotrophic lateral sclerosis (ALS), is a novel substrate for c-Abl. The phosphorylation of tyrosine 43 of TDP-43 by c-Abl led to increased TDP-43 levels in the cytoplasm and increased the formation of G3BP1-positive stress granules in SH-SY5Y cells. The kinase-dead mutant of c-Abl had no effect on the cytoplasmic localization of TDP-43. The expression of phosphor-mimetic mutant Y43E of TDP-43 in primary cortical neurons accumulated the neurite granule. Furthermore, the phosphorylation of TDP-43 at tyrosine 43 by c-Abl promoted the aggregation of TDP-43 and increased neuronal cell death in primary cortical neurons, but not in c-Abl-deficient primary cortical neurons. Identification of c-Abl as the kinase of TDP43 provides new insight into the pathogenesis of ALS.


Subject(s)
Amyotrophic Lateral Sclerosis , Proto-Oncogene Proteins c-abl , Humans , Amyotrophic Lateral Sclerosis/genetics , Amyotrophic Lateral Sclerosis/metabolism , Amyotrophic Lateral Sclerosis/pathology , DNA Helicases/metabolism , DNA-Binding Proteins/genetics , DNA-Binding Proteins/metabolism , Neuroblastoma , Phosphorylation , Poly-ADP-Ribose Binding Proteins/metabolism , RNA Helicases/metabolism , RNA Recognition Motif Proteins/metabolism , Proto-Oncogene Proteins c-abl/genetics , Proto-Oncogene Proteins c-abl/metabolism , Tyrosine/metabolism
6.
Sensors (Basel) ; 22(22)2022 Nov 18.
Article in English | MEDLINE | ID: mdl-36433508

ABSTRACT

Plant diseases are a major cause of reduction in agricultural output, which leads to severe economic losses and unstable food supply. The citrus plant is an economically important fruit crop grown and produced worldwide. However, citrus plants are easily affected by various factors, such as climate change, pests, and diseases, resulting in reduced yield and quality. Advances in computer vision in recent years have been widely used for plant disease detection and classification, providing opportunities for early disease detection, and resulting in improvements in agriculture. Particularly, the early and accurate detection of citrus diseases, which are vulnerable to pests, is very important to prevent the spread of pests and reduce crop damage. Research on citrus pest disease is ongoing, but it is difficult to apply research results to cultivation owing to a lack of datasets for research and limited types of pests. In this study, we built a dataset by self-collecting a total of 20,000 citrus pest images, including fruits and leaves, from actual cultivation sites. The constructed dataset was trained, verified, and tested using a model that had undergone five transfer learning steps. All models used in the experiment had an average accuracy of 97% or more and an average f1 score of 96% or more. We built a web application server using the EfficientNet-b0 model, which exhibited the best performance among the five learning models. The built web application tested citrus pest disease using image samples collected from websites other than the self-collected image samples and prepared data, and both samples correctly classified the disease. The citrus pest automatic diagnosis web system using the model proposed in this study plays a useful auxiliary role in recognizing and classifying citrus diseases. This can, in turn, help improve the overall quality of citrus fruits.


Subject(s)
Citrus , Deep Learning , Plant Diseases , Agriculture , Fruit
7.
Biomicrofluidics ; 16(4): 044102, 2022 Jul.
Article in English | MEDLINE | ID: mdl-35909647

ABSTRACT

Systematic evolution of ligands by exponential enrichment (SELEX) is a method that is generally used for developing aptamers, which have arisen the promising alternatives for antibodies. However, conventional SELEX methods have limitations, such as a limited selection of target molecules, time-consuming and complex fabrication processes, and labor-intensive processes, which result in low selection yields. Here, we used (i) graphene oxide (GO)-coated magnetic nanoparticles in the selection process for separation and label-free detection and (ii) a multilayered microfluidic device manufactured using a three-dimensionally printed mold that is equipped with automated control valves to achieve precise fluid flows. The developed on-chip aptamer selection device and GO-coated magnetic nanoparticles were used to screen aptamer candidates for adenosine in eight cycles of the selection process within approximately 2 h for each cycle. Based on results from isothermal titration calorimetry, an aptamer with a dissociation constant of 18.6 ± 1.5 µM was selected. Therefore, the on-chip platform based on GO-coated magnetic nanoparticles provides a novel label-free screening technology for biosensors and micro/nanobiotechnology for achieving high-quality aptamers.

8.
Nanomaterials (Basel) ; 12(15)2022 Jul 28.
Article in English | MEDLINE | ID: mdl-35957030

ABSTRACT

The uneven deposition at the edges of an evaporating droplet, termed the coffee-ring effect, has been extensively studied during the past few decades to better understand the underlying cause, namely the flow dynamics, and the subsequent patterns formed after drying. The non-uniform evaporation rate across the colloidal droplet hampers the formation of a uniform and homogeneous film in printed electronics, rechargeable batteries, etc., and often causes device failures. This review aims to highlight the diverse range of techniques used to alleviate the coffee-ring effect, from classic methods such as adding chemical additives, applying external sources, and manipulating geometrical configurations to recently developed advancements, specifically using bubbles, humidity, confined systems, etc., which do not involve modification of surface, particle or liquid properties. Each of these methodologies mitigates the edge deposition via multi-body interactions, for example, particle-liquid, particle-particle, particle-solid interfaces and particle-flow interactions. The mechanisms behind each of these approaches help to find methods to inhibit the non-uniform film formation, and the corresponding applications have been discussed together with a critical comparison in detail. This review could pave the way for developing inks and processes to apply in functional coatings and printed electronic devices with improved efficiency and device yield.

9.
Micromachines (Basel) ; 13(8)2022 Jul 29.
Article in English | MEDLINE | ID: mdl-36014138

ABSTRACT

Lab-on-a-CD (LOCD) is gaining importance as a diagnostic platform due to being low-cost, easy-to-use, and portable. During LOCD usage, mixing and reaction are two processes that play an essential role in biochemical applications such as point-of-care diagnosis. In this paper, we numerically and experimentally investigate the effects of the Coriolis and Euler forces in the mixing chamber during the acceleration and deceleration of a rotating disk. The mixing performance is investigated under various conditions that have not been reported, such as rotational condition, chamber aspect ratio at a constant volume, and obstacle arrangement in the chamber. During disk acceleration and deceleration, the Euler force difference in the radial direction causes rotating flows, while the Coriolis force induces perpendicular vortices. Increasing the maximum rotational velocity improves the maximum rotational displacement, resulting in better mixing performance. A longer rotational period increases the interfacial area between solutions and enhances mixing. Mixing performance also improves when there is a substantial difference between Euler forces at the inner and outer radii. Furthermore, adding obstacles in the angular direction also passively promotes or inhibits mixing by configuration. This quantitative investigation provides valuable information for designing and developing high throughput and multiplexed point-of-care LOCDs.

11.
Neuron ; 109(23): 3758-3774.e11, 2021 12 01.
Article in English | MEDLINE | ID: mdl-34644545

ABSTRACT

Impairment in glucocerebrosidase (GCase) is strongly associated with the development of Parkinson's disease (PD), yet the regulators responsible for its impairment remain elusive. In this paper, we identify the E3 ligase Thyroid Hormone Receptor Interacting Protein 12 (TRIP12) as a key regulator of GCase. TRIP12 interacts with and ubiquitinates GCase at lysine 293 to control its degradation via ubiquitin proteasomal degradation. Ubiquitinated GCase by TRIP12 leads to its functional impairment through premature degradation and subsequent accumulation of α-synuclein. TRIP12 overexpression causes mitochondrial dysfunction, which is ameliorated by GCase overexpression. Further, conditional TRIP12 knockout in vitro and knockdown in vivo promotes the expression of GCase, which blocks α-synuclein preformed fibrils (α-syn PFFs)-provoked dopaminergic neurodegeneration. Moreover, TRIP12 accumulates in human PD brain and α-synuclein-based mouse models. The identification of TRIP12 as a regulator of GCase provides a new perspective on the molecular mechanisms underlying dysfunctional GCase-driven neurodegeneration in PD.


Subject(s)
Carrier Proteins/metabolism , Glucosylceramidase , Parkinson Disease , Ubiquitin-Protein Ligases/metabolism , Animals , Brain/metabolism , Disease Models, Animal , Glucosylceramidase/genetics , Glucosylceramidase/metabolism , Mice , Parkinson Disease/genetics , Parkinson Disease/metabolism , Ubiquitination , alpha-Synuclein/metabolism
12.
J Med Chem ; 64(20): 15091-15110, 2021 10 28.
Article in English | MEDLINE | ID: mdl-34583507

ABSTRACT

Parkinson's disease (PD) is a progressive neurodegenerative disorder that affects movement. The nonreceptor tyrosine kinase c-Abl has shown a potential role in the progression of PD. As such, c-Abl inhibition is a promising candidate for neuroprotection in PD and α-synucleinopathies. Compound 5 is a newly synthesized blood-brain barrier penetrant c-Abl inhibitor with higher efficacy than existing inhibitors. The objective of the current study was to demonstrate the neuroprotective effects of compound 5 on the α-synuclein preformed fibril (α-syn PFF) mouse model of PD. Compound 5 significantly reduced neurotoxicity, activation of c-Abl, and Lewy body pathology caused by α-syn PFF in cortical neurons. Additionally, compound 5 markedly ameliorated the loss of dopaminergic neurons, c-Abl activation, Lewy body pathology, neuroinflammatory responses, and behavioral deficits induced by α-syn PFF injection in vivo. Taken together, these results suggest that compound 5 could be a pharmaceutical agent to prevent the progression of PD and α-synucleinopathies.


Subject(s)
Neuroprotective Agents/pharmacology , Parkinson Disease/drug therapy , Proto-Oncogene Proteins c-abl/antagonists & inhibitors , Dose-Response Relationship, Drug , Humans , Models, Molecular , Molecular Structure , Neuroprotective Agents/chemistry , Parkinson Disease/metabolism , Proto-Oncogene Proteins c-abl/metabolism , Structure-Activity Relationship
13.
Acta Neuropathol Commun ; 9(1): 78, 2021 04 26.
Article in English | MEDLINE | ID: mdl-33902708

ABSTRACT

Alzheimer's disease (AD) is the most common cause of age-related dementia. Increasing evidence suggests that neuroinflammation mediated by microglia and astrocytes contributes to disease progression and severity in AD and other neurodegenerative disorders. During AD progression, resident microglia undergo proinflammatory activation, resulting in an increased capacity to convert resting astrocytes to reactive astrocytes. Therefore, microglia are a major therapeutic target for AD and blocking microglia-astrocyte activation could limit neurodegeneration in AD. Here we report that NLY01, an engineered exedin-4, glucagon-like peptide-1 receptor (GLP-1R) agonist, selectively blocks ß-amyloid (Aß)-induced activation of microglia through GLP-1R activation and inhibits the formation of reactive astrocytes as well as preserves neurons in AD models. In two transgenic AD mouse models (5xFAD and 3xTg-AD), repeated subcutaneous administration of NLY01 blocked microglia-mediated reactive astrocyte conversion and preserved neuronal viability, resulting in improved spatial learning and memory. Our study indicates that the GLP-1 pathway plays a critical role in microglia-reactive astrocyte associated neuroinflammation in AD and the effects of NLY01 are primarily mediated through a direct action on Aß-induced GLP-1R+ microglia, contributing to the inhibition of astrocyte reactivity. These results show that targeting upregulated GLP-1R in microglia is a viable therapy for AD and other neurodegenerative disorders.


Subject(s)
Alzheimer Disease/metabolism , Astrocytes/metabolism , Glucagon-Like Peptide-1 Receptor/metabolism , Microglia/metabolism , Neuroprotection/physiology , Alzheimer Disease/genetics , Alzheimer Disease/prevention & control , Amyloid beta-Peptides/toxicity , Animals , Astrocytes/drug effects , Cells, Cultured , Exenatide/administration & dosage , Glucagon-Like Peptide-1 Receptor/agonists , Humans , Male , Maze Learning/drug effects , Maze Learning/physiology , Mice , Mice, Transgenic , Microglia/drug effects , Neuroprotection/drug effects , Neuroprotective Agents/administration & dosage , Peptide Fragments/toxicity
14.
Prog Neurobiol ; 198: 101915, 2021 03.
Article in English | MEDLINE | ID: mdl-32966834

ABSTRACT

While positive regulators of hippocampal long-term potentiation (LTP) have extensively been investigated, relatively little is known about the inhibitory regulators of LTP. We previously reported that Cyclin Y (CCNY), a member of cyclin family generally known to function in proliferating cells, is a novel postsynaptic protein that serves as a negative regulator of functional LTP. However, whether CCNY plays a role in structural LTP, which is mechanistically linked to functional LTP, and which mechanisms are involved in the CCNY-mediated suppression of LTP at the molecular level remain elusive. Here, we report that CCNY negatively regulates the plasticity-induced changes in spine morphology through the control of actin dynamics. We observed that CCNY directly binds to filamentous actin and interferes with LTP-induced actin polymerization as well as depolymerization by blocking the activation of cofilin, an actin-depolymerizing factor, thus resulting in less plastic spines and the impairment of structural LTP. These data suggest that CCNY acts as an inhibitory regulator for both structural and functional LTP by modulating actin dynamics through the cofilin-actin pathway. Collectively, our findings provide a mechanistic insight into the inhibitory modulation of hippocampal LTP by CCNY, highlighting a novel function of a cyclin family protein in non-proliferating neuronal cells.


Subject(s)
Neuronal Plasticity , Actin Depolymerizing Factors , Actins , Cyclins , Microfilament Proteins , Synapses
15.
Neuron ; 103(4): 627-641.e7, 2019 08 21.
Article in English | MEDLINE | ID: mdl-31255487

ABSTRACT

Analysis of human pathology led Braak to postulate that α-synuclein (α-syn) pathology could spread from the gut to brain via the vagus nerve. Here, we test this postulate by assessing α-synucleinopathy in the brain in a novel gut-to-brain α-syn transmission mouse model, where pathological α-syn preformed fibrils were injected into the duodenal and pyloric muscularis layer. Spread of pathologic α-syn in brain, as assessed by phosphorylation of serine 129 of α-syn, was observed first in the dorsal motor nucleus, then in caudal portions of the hindbrain, including the locus coeruleus, and much later in basolateral amygdala, dorsal raphe nucleus, and the substantia nigra pars compacta. Moreover, loss of dopaminergic neurons and motor and non-motor symptoms were observed in a similar temporal manner. Truncal vagotomy and α-syn deficiency prevented the gut-to-brain spread of α-synucleinopathy and associated neurodegeneration and behavioral deficits. This study supports the Braak hypothesis in the etiology of idiopathic Parkinson's disease (PD).


Subject(s)
Axonal Transport , Parkinsonian Disorders/etiology , Protein Aggregates , Vagus Nerve/metabolism , alpha-Synuclein/pharmacokinetics , Animals , Brain Chemistry , Dopaminergic Neurons/metabolism , Dopaminergic Neurons/pathology , Duodenum/innervation , Duodenum/metabolism , Humans , Injections, Intramuscular , Lewy Bodies/metabolism , Maze Learning , Memory Disorders/etiology , Mice , Mice, Inbred C57BL , Mice, Knockout , Models, Neurological , Muscle, Smooth/innervation , Muscle, Smooth/metabolism , Nesting Behavior/physiology , Parkinsonian Disorders/metabolism , Parkinsonian Disorders/prevention & control , Parkinsonian Disorders/psychology , Phosphorylation , Protein Processing, Post-Translational , Pylorus/innervation , Pylorus/metabolism , Rotarod Performance Test , Vagotomy , alpha-Synuclein/administration & dosage , alpha-Synuclein/deficiency , alpha-Synuclein/toxicity
16.
Brain ; 142(8): 2380-2401, 2019 08 01.
Article in English | MEDLINE | ID: mdl-31237944

ABSTRACT

α-Synuclein misfolding and aggregation plays a major role in the pathogenesis of Parkinson's disease. Although loss of function mutations in the ubiquitin ligase, parkin, cause autosomal recessive Parkinson's disease, there is evidence that parkin is inactivated in sporadic Parkinson's disease. Whether parkin inactivation is a driver of neurodegeneration in sporadic Parkinson's disease or a mere spectator is unknown. Here we show that parkin in inactivated through c-Abelson kinase phosphorylation of parkin in three α-synuclein-induced models of neurodegeneration. This results in the accumulation of parkin interacting substrate protein (zinc finger protein 746) and aminoacyl tRNA synthetase complex interacting multifunctional protein 2 with increased parkin interacting substrate protein levels playing a critical role in α-synuclein-induced neurodegeneration, since knockout of parkin interacting substrate protein attenuates the degenerative process. Thus, accumulation of parkin interacting substrate protein links parkin inactivation and α-synuclein in a common pathogenic neurodegenerative pathway relevant to both sporadic and familial forms Parkinson's disease. Thus, suppression of parkin interacting substrate protein could be a potential therapeutic strategy to halt the progression of Parkinson's disease and related α-synucleinopathies.


Subject(s)
Parkinson Disease/metabolism , Repressor Proteins/metabolism , Ubiquitin-Protein Ligases/metabolism , alpha-Synuclein/metabolism , Animals , Female , Humans , Male , Mice , Mice, Knockout , Mice, Transgenic , Parkinson Disease/pathology
17.
Mol Neurobiol ; 56(10): 6725-6735, 2019 Oct.
Article in English | MEDLINE | ID: mdl-30915712

ABSTRACT

Disrupted-in-Schizophrenia 1 (DISC1) is a scaffold protein implicated in various psychiatric diseases. Dysregulation of the dopamine system has been associated with DISC1 deficiency, while the molecular mechanism is unclear. In this study, we propose a novel molecular mechanism underlying the transcriptional regulation of the dopamine D1 receptor (D1R) in the striatum via DISC1. We verified the increase in D1R at the transcriptional level in the striatum of DISC1-deficient mouse models and altered histone acetylation status at the D1r locus. We identified a functional interaction between DISC1 and Krüppel-like factor 16 (KLF16). KLF16 translocates DISC1 into the nucleus and forms a regulatory complex by recruiting SIN3A corepressor complexes to the D1r locus. Moreover, DISC1-deficient mice have altered D1R-mediated signaling in the striatum and exhibit hyperlocomotion in response to cocaine; the blockade of D1R suppresses these effects. Taken together, our results suggest that nuclear DISC1 plays a critical role in the transcriptional regulation of D1R in the striatal neuron, providing a mechanistic link between DISC1 and dopamine-related psychiatric symptoms.


Subject(s)
Nerve Tissue Proteins/metabolism , Receptors, Dopamine D1/metabolism , Repressor Proteins/metabolism , Transcription, Genetic , Animals , Behavior, Animal , Cell Nucleus/metabolism , Co-Repressor Proteins/metabolism , Corpus Striatum/metabolism , Genetic Loci , Kruppel-Like Transcription Factors/metabolism , Mice, Inbred C57BL , Nerve Tissue Proteins/deficiency , Protein Binding , Protein Transport , Receptors, Dopamine D1/genetics , Signal Transduction , Sin3 Histone Deacetylase and Corepressor Complex , Up-Regulation/genetics
18.
J Neurochem ; 149(3): 413-426, 2019 05.
Article in English | MEDLINE | ID: mdl-30488434

ABSTRACT

Misfolded proteins with abnormal polyglutamine (polyQ) expansion cause neurodegenerative disorders, including Huntington's disease. Recently, it was found that polyQ aggregates accumulate as a result of vaccinia-related kinase 2 (VRK2)-mediated degradation of TCP-1 ring complex (TRiC)/chaperonin-containing TCP-1 (CCT), which has an essential role in the prevention of polyQ protein aggregation and cytotoxicity. The levels of VRK2 are known to be much higher in actively proliferating cells but are maintained at a low level in the brain via an unknown mechanism. Here, we found that basal levels of neuronal cell-specific VRK2 mRNA are maintained by post-transcriptional, rather than transcriptional, regulation. Moreover, heterogeneous nuclear ribonucleoprotein Q (HNRNP Q) specifically binds to the 3'untranslated region of VRK2 mRNA in neuronal cells to reduce the mRNA stability. As a result, we found a dramatic decrease in CCT4 protein levels in response to a reduction in HNRNP Q levels, which was followed by an increase in polyQ aggregation in human neuroblastoma cells and mouse cortical neurons. Taken together, these results provide new insights into how neuronal HNRNP Q decreases VRK2 mRNA stability and contributes to the prevention of Huntington's disease, while also identifying new prognostic markers of HD.


Subject(s)
Gene Expression Regulation/genetics , Heterogeneous-Nuclear Ribonucleoproteins/metabolism , Huntingtin Protein/metabolism , Huntington Disease/metabolism , Protein Serine-Threonine Kinases/biosynthesis , Animals , Brain/metabolism , Mice , Mice, Inbred C57BL , Peptides/metabolism , RNA Processing, Post-Transcriptional
19.
Nat Nanotechnol ; 13(9): 812-818, 2018 09.
Article in English | MEDLINE | ID: mdl-29988049

ABSTRACT

Though emerging evidence indicates that the pathogenesis of Parkinson's disease is strongly correlated to the accumulation1,2 and transmission3,4 of α-synuclein (α-syn) aggregates in the midbrain, no anti-aggregation agents have been successful at treating the disease in the clinic. Here, we show that graphene quantum dots (GQDs) inhibit fibrillization of α-syn and interact directly with mature fibrils, triggering their disaggregation. Moreover, GQDs can rescue neuronal death and synaptic loss, reduce Lewy body and Lewy neurite formation, ameliorate mitochondrial dysfunctions, and prevent neuron-to-neuron transmission of α-syn pathology provoked by α-syn preformed fibrils5,6. We observe, in vivo, that GQDs penetrate the blood-brain barrier and protect against dopamine neuron loss induced by α-syn preformed fibrils, Lewy body/Lewy neurite pathology and behavioural deficits.


Subject(s)
Blood-Brain Barrier/metabolism , Graphite , Parkinson Disease/prevention & control , Protein Aggregation, Pathological/prevention & control , Quantum Dots , alpha-Synuclein/metabolism , Animals , Blood-Brain Barrier/pathology , Cells, Cultured , Graphite/chemistry , Graphite/pharmacokinetics , Graphite/pharmacology , Humans , Lewy Bodies/metabolism , Lewy Bodies/pathology , Mice , Parkinson Disease/metabolism , Parkinson Disease/pathology , Protein Aggregation, Pathological/metabolism , Protein Aggregation, Pathological/pathology , Quantum Dots/chemistry , Synapses/metabolism , Synapses/pathology
20.
Hum Mol Genet ; 27(13): 2344-2356, 2018 07 01.
Article in English | MEDLINE | ID: mdl-29897434

ABSTRACT

Accumulating evidence suggests that the non-receptor tyrosine kinase c-Abl plays an important role in the progression of Parkinson's disease (PD) and c-Abl inhibition could be neuroprotective in PD and related α-synucleinopathies. Nilotinib, a c-Abl inhibitor, has shown improved motor and cognitive symptoms in PD patients. However, issues concerning blood-brain barrier (BBB) penetration, lack of selectivity and safety still remain. Radotinib HCl is a selective Bcr-Abl kinase inhibitor that not only effectively access the brain, but also exhibits greater pharmacokinetic properties and safety profiles compared to Nilotinib and other c-Abl inhibitors. Here, we show the neuroprotective efficacy of Radotinib HCl, a brain penetrant c-Abl inhibitor, in a pre-clinical model of PD. Importantly, in vitro studies demonstrate that the treatment of Radotinib HCl protects the α-synuclein preformed fibrils (PFF)-induced neuronal toxicity, reduces the α-synuclein PFF-induced Lewy bodies (LB)/Lewy neurites (LN)-like pathology and inhibits the α-synuclein PFF-induced c-Abl activation in primary cortical neurons. Furthermore, administration of Radotinib HCl inhibits c-Abl activation and prevents dopaminergic neuron loss, neuroinflammation and behavioral deficits following α-synuclein PFF-induced toxicity in vivo. Taken together, our findings indicate that Radotinib HCl has beneficial neuroprotective effects in PD and provides an evidence that selective and brain permeable c-Abl inhibitors can be potential therapeutic agents for the treatment of PD and related α-synucleinopathies.


Subject(s)
Brain/drug effects , Nerve Degeneration/drug therapy , Parkinson Disease/drug therapy , Proto-Oncogene Proteins c-abl/antagonists & inhibitors , alpha-Synuclein/genetics , Animals , Blood-Brain Barrier , Brain/metabolism , Disease Models, Animal , Dopamine/metabolism , Dopaminergic Neurons/drug effects , Dopaminergic Neurons/pathology , Humans , Lewy Bodies/drug effects , Mice , Nerve Degeneration/genetics , Neuroprotective Agents/administration & dosage , Parkinson Disease/genetics , Parkinson Disease/pathology , Proto-Oncogene Proteins c-abl/genetics , Pyrimidines/administration & dosage , Sesquiterpenes/administration & dosage
SELECTION OF CITATIONS
SEARCH DETAIL
...