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1.
Clin Immunol ; 258: 109874, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38113962

RESUMO

Sle1 and Faslpr are two lupus susceptibility loci that lead to manifestations of systemic lupus erythematosus. To evaluate the dosage effects of Faslpr in determining cellular and serological phenotypes associated with lupus, we developed a new C57BL/6 (B6) congenic lupus strain, B6.Sle1/Sle1.Faslpr/+ (Sle1homo.lprhet) and compared it with B6.Faslpr/lpr (lprhomo), B6.Sle1/Sle1 (Sle1homo), and B6.Sle1/Sle1.Faslpr/lpr (Sle1homo.lprhomo) strains. Whereas Sle1homo.lprhomo mice exhibited profound lymphoproliferation and early mortality, Sle1homo.lprhet mice had a lifespan comparable to B6 mice, with no evidence of splenomegaly or lymphadenopathy. Compared to B6 monogenic lupus strains, Sle1homo.lprhet mice exhibited significantly elevated serum ANA antibodies and increased proteinuria. Additionally, Sle1homo.lprhet T cells had an increased propensity to differentiate into Th1 cells. Gene dose effects of Faslpr were noted in upregulating serum IL-1⍺, IL-2, and IL-27. Taken together, Sle1homo.lprhet strain is a new C57BL/6-based model of lupus, ideal for genetic studies, autoantibody repertoire investigation, and for exploring Th1 effector cell skewing without early-age lymphoproliferative autoimmunity.


Assuntos
Lúpus Eritematoso Sistêmico , Camundongos , Animais , Camundongos Endogâmicos C57BL , Lúpus Eritematoso Sistêmico/genética , Autoimunidade , Diferenciação Celular , Dosagem de Genes , Camundongos Endogâmicos MRL lpr
2.
Biochem Biophys Res Commun ; 734: 150593, 2024 11 19.
Artigo em Inglês | MEDLINE | ID: mdl-39217812

RESUMO

Asthma is a complex inflammatory airway disease that arises from the interplay between genetic predisposition and environmental influences. Leucine-rich repeat kinase 2 (LRRK2), a gene commonly associated with Parkinson's disease, has recently gained attention for its role in immune regulation and inflammation beyond the brain. However, its involvement in asthma has not yet been reported. In this study, we used LRRK2 G2019S transgenic mice and LRRK2 knockout mice to establish asthmatic models to explore LRRK2 impact on asthma. We found that LRRK2 G2019S transgenic mice showed exacerbated airway hyperresponsiveness (AHR) and airway inflammation in asthma mouse models induced by house dust mite. RNA sequencing data unveiled that the LRRK2 G2019S mutation enhanced immune response pathways, including NOD-like receptor, cellular response to interferon ß and activation of innate immune response signaling. Conversely, LRRK2 deficiency attenuated AHR and airway inflammation in the same asthma models. Our study offers new insights into the role of LRRK2 in allergic inflammation and highlights its potential as a therapeutic target for asthma.


Assuntos
Asma , Modelos Animais de Doenças , Serina-Treonina Proteína Quinase-2 com Repetições Ricas em Leucina , Animais , Serina-Treonina Proteína Quinase-2 com Repetições Ricas em Leucina/genética , Asma/imunologia , Asma/genética , Camundongos , Camundongos Transgênicos , Camundongos Knockout , Camundongos Endogâmicos C57BL , Imunidade Inata/genética , Mutação , Pyroglyphidae/imunologia , Transdução de Sinais , Inflamação/genética , Inflamação/imunologia
3.
Transp Policy (Oxf) ; 115: 220-238, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34840441

RESUMO

The outbreak of the COVID-19 epidemic has brought enormous impacts and changes to human mobility. To better understand and quantify the impacts of COVID-19 on city-wide ride-sourcing and taxi markets, we present exploratory evidence on the factors such as coronavirus cases related attributes, policy-related attributes, operational status of transportation, socio-economic status related variables, demographics related variables, and other factors. Based on 5-month real-world ride-sourcing and taxi datasets in Ningbo, China, including 37-million trips, we study the temporal variations of drivers' working characteristics and productivity of ride-sourcing and taxi fleets. The spatial heterogeneity of the impacts of COVID-19 on taxi and ride-sourcing trips is demonstrated in terms of traffic analysis zones (TAZs). Regression models are established to examine the impacts of a variety of explanatory variables, including COVID-19 related variables, on the district-level productivity of taxi and ride-sourcing services. The results show that the accumulated cured coronavirus cases, policy of closed management, operational status of mass transit, and average fee spent on transportation per capita significantly impact the productivity of the taxi and ride-sourcing fleets. This paper empirically reveals the influence of the epidemic on ride-sourcing and taxi markets and the temporal and spatial variations. The findings can support decision-making to restore the ride-sourcing and taxi markets and benefit other COVID-19 related research efforts.

4.
Ann Neurol ; 85(4): 593-599, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30761591

RESUMO

OBJECTIVE: LRRK2 mutations, the most common genetic cause of Parkinson disease (PD), display incomplete penetrance, indicating the importance of other genetic and environmental influences on disease pathogenesis in LRRK2 mutation carriers. The present study investigates whether urate, an antioxidant, Nrf2 activator, and inverse risk factor for idiopathic PD, is one such candidate biomarker of PD risk modulation in pathogenic LRRK2 mutation carriers. METHODS: Banked plasma samples or urate levels were obtained for 3 cohorts of age- and sex-matched subjects with and without a known LRRK2 mutation in PD and unaffected controls to conduct a pilot study of 192 subjects from the LRRK2 Cohort Consortium (LCC) and 2 validation studies of 380 additional subjects from the LCC and 922 subjects from the Parkinson's Progression Markers Initiative. Urate levels were compared by multiple regression between subjects with and without a PD diagnosis conditional on LRRK2 status, controlling for age and sex. RESULTS: Nonmanifesting LRRK2 mutation carriers had significantly higher levels of urate than those who developed PD in each of the 3 independent cohorts. A meta-analysis demonstrated an adjusted mean difference of 0.62 mg/dL (p < 0.001), with similar results for separate assessments of women (p < 0.02) and men (p < 0.001). A 2 mg/dL increment in urate concentration decreased the odds of having PD by approximately 50% (odds ratio = 0.48, p = 0.004). INTERPRETATION: These findings identify and substantiate urate as a biomarker of resistance to PD among LRRK2 mutation carriers. Ann Neurol 2019;85:593-599.


Assuntos
Resistência à Doença/genética , Serina-Treonina Proteína Quinase-2 com Repetições Ricas em Leucina/genética , Mutação/genética , Doença de Parkinson/sangue , Doença de Parkinson/genética , Ácido Úrico/sangue , Adulto , Idoso , Biomarcadores/sangue , Estudos de Coortes , Feminino , Predisposição Genética para Doença/genética , Heterozigoto , Humanos , Masculino , Pessoa de Meia-Idade , Doença de Parkinson/diagnóstico
5.
Proc Natl Acad Sci U S A ; 114(23): E4676-E4685, 2017 06 06.
Artigo em Inglês | MEDLINE | ID: mdl-28533375

RESUMO

The activity of the transcription factor nuclear factor-erythroid 2 p45-derived factor 2 (NRF2) is orchestrated and amplified through enhanced transcription of antioxidant and antiinflammatory target genes. The present study has characterized a triazole-containing inducer of NRF2 and elucidated the mechanism by which this molecule activates NRF2 signaling. In a highly selective manner, the compound covalently modifies a critical stress-sensor cysteine (C151) of the E3 ligase substrate adaptor protein Kelch-like ECH-associated protein 1 (KEAP1), the primary negative regulator of NRF2. We further used this inducer to probe the functional consequences of selective activation of NRF2 signaling in Huntington's disease (HD) mouse and human model systems. Surprisingly, we discovered a muted NRF2 activation response in human HD neural stem cells, which was restored by genetic correction of the disease-causing mutation. In contrast, selective activation of NRF2 signaling potently repressed the release of the proinflammatory cytokine IL-6 in primary mouse HD and WT microglia and astrocytes. Moreover, in primary monocytes from HD patients and healthy subjects, NRF2 induction repressed expression of the proinflammatory cytokines IL-1, IL-6, IL-8, and TNFα. Together, our results demonstrate a multifaceted protective potential of NRF2 signaling in key cell types relevant to HD pathology.


Assuntos
Doença de Huntington/metabolismo , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Adulto , Idoso , Animais , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Células Cultivadas , Citocinas/metabolismo , Modelos Animais de Doenças , Feminino , Células HEK293 , Humanos , Doença de Huntington/genética , Proteína 1 Associada a ECH Semelhante a Kelch/química , Intoxicação por MPTP/metabolismo , Intoxicação por MPTP/prevenção & controle , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Microglia/efeitos dos fármacos , Microglia/metabolismo , Pessoa de Meia-Idade , Fator 2 Relacionado a NF-E2/química , Células-Tronco Neurais/metabolismo , Fármacos Neuroprotetores/farmacologia , Conformação Proteica/efeitos dos fármacos , Ratos , Transdução de Sinais
6.
Mol Cell Neurosci ; 92: 12-16, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29928993

RESUMO

Dominant mutations in an antioxidant enzyme superoxide dismutase-1 (SOD1) cause amyotrophic lateral sclerosis (ALS), an adult-onset neurodegenerative disease characterized by loss of motor neurons. Oxidative stress has also been linked to many of the neurodegenerative diseases and is likely a central mechanism of motor neuron death in ALS. Astrocytes derived from mutant SOD1G93A mouse models or patients play a significant role in the degeneration of spinal motor neurons in ALS through a non-cell-autonomous process. Here we characterize the neuroprotective effects and mechanisms of urate (a.k.a. uric acid), a major endogenous antioxidant and a biomarker of favorable ALS progression rates, in a cellular model of ALS. Our results demonstrate a significant protective effect of urate against motor neuron injury evoked by mutant astrocytes derived from SOD1G93A mice or hydrogen peroxide induced oxidative stress. Overall, these results implicate astrocyte dependent protective effect of urate in a cellular model of ALS. These findings together with our biomarker data may advance novel targets for treating motor neuron disease.


Assuntos
Esclerose Lateral Amiotrófica/metabolismo , Antioxidantes/farmacologia , Astrócitos/metabolismo , Neurônios Motores/metabolismo , Estresse Oxidativo , Superóxido Dismutase-1/genética , Ácido Úrico/farmacologia , Esclerose Lateral Amiotrófica/genética , Animais , Linhagem Celular , Células Cultivadas , Meios de Cultivo Condicionados/farmacologia , Camundongos , Neurônios Motores/efeitos dos fármacos , Mutação , Ácido Úrico/metabolismo
7.
Ann Neurol ; 81(3): 395-406, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28019657

RESUMO

OBJECTIVE: Individuals with Parkinson disease are more likely to develop melanoma, and melanoma patients are reciprocally at higher risk of developing Parkinson disease. Melanoma is strongly tied to red hair/fair skin, a phenotype of loss-of-function polymorphisms in the MC1R (melanocortin 1 receptor) gene. Loss-of-function variants of MC1R have also been linked to increased risk of Parkinson disease. The present study is to investigate the role of MC1R in dopaminergic neurons in vivo. METHODS: Genetic and pharmacological approaches were employed to manipulate MC1R, and nigrostriatal dopaminergic integrity was determined by comprehensive behavioral, neurochemical, and neuropathological measures. RESULTS: MC1Re/e mice, which carry an inactivating mutation of MC1R and mimic the human redhead phenotype, have compromised nigrostriatal dopaminergic neuronal integrity, and they are more susceptible to dopaminergic neuron toxins 6-hydroxydopamine and 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP). Furthermore, a selective MC1R agonist protects against MPTP-induced dopaminergic neurotoxicity. INTERPRETATION: Our findings reveal a protective role of MC1R in the nigrostriatal dopaminergic system, and they provide a rationale for MC1R as a potential therapeutic target for Parkinson disease. Together with its established role in melanoma, MC1R may represent a common pathogenic pathway for melanoma and Parkinson disease. Ann Neurol 2017;81:395-406.


Assuntos
Neurônios Dopaminérgicos/metabolismo , Neostriado/metabolismo , Pigmentação/genética , Receptor Tipo 1 de Melanocortina/fisiologia , Substância Negra/metabolismo , 1-Metil-4-Fenil-1,2,3,6-Tetra-Hidropiridina/farmacologia , Animais , Comportamento Animal , Modelos Animais de Doenças , Neurônios Dopaminérgicos/efeitos dos fármacos , Neurônios Dopaminérgicos/patologia , Humanos , Masculino , Melanoma/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Neostriado/efeitos dos fármacos , Neurotoxinas/farmacologia , Doença de Parkinson/genética , Substância Negra/efeitos dos fármacos
8.
Proc Natl Acad Sci U S A ; 110(1): 300-5, 2013 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-23248282

RESUMO

Urate is the end product of purine metabolism in humans, owing to the evolutionary disruption of the gene encoding urate oxidase (UOx). Elevated urate can cause gout and urolithiasis and is associated with cardiovascular and other diseases. However, urate also possesses antioxidant and neuroprotective properties. Recent convergence of epidemiological and clinical data has identified urate as a predictor of both reduced risk and favorable progression of Parkinson's disease (PD). In rodents, functional UOx catalyzes urate oxidation to allantoin. We found that UOx KO mice with a constitutive mutation of the gene have increased concentrations of brain urate. By contrast, UOx transgenic (Tg) mice overexpressing the enzyme have reduced brain urate concentrations. Effects of the complementary UOx manipulations were assessed in a mouse intrastriatal 6-hydroxydopamine (6-OHDA) model of hemiparkinsonism. UOx KO mice exhibit attenuated toxic effects of 6-OHDA on nigral dopaminergic cell counts, striatal dopamine content, and rotational behavior. Conversely, Tg overexpression of UOx exacerbates these morphological, neurochemical, and functional lesions of the dopaminergic nigrostriatal pathway. Together our data support a neuroprotective role of endogenous urate in dopaminergic neurons and strengthen the rationale for developing urate-elevating strategies as potential disease-modifying therapy for PD.


Assuntos
Encéfalo/metabolismo , Transtornos Parkinsonianos/metabolismo , Urato Oxidase/metabolismo , Ácido Úrico/metabolismo , Alantoína/metabolismo , Análise de Variância , Animais , Western Blotting , Dopamina/metabolismo , Neurônios Dopaminérgicos/efeitos dos fármacos , Imuno-Histoquímica , Camundongos , Camundongos Knockout , Camundongos Transgênicos , Movimento/fisiologia , Oxidopamina/toxicidade , Urato Oxidase/genética
9.
Neurobiol Dis ; 82: 574-579, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26341543

RESUMO

Urate has emerged as a promising target for neuroprotection based on epidemiological observations, preclinical models, and early clinical trial results in multiple neurologic diseases, including Parkinson's disease (PD). This study investigates the astrocytic mechanism of urate's neuroprotective effect. Targeted biochemical screens of conditioned medium from urate- versus vehicle-treated astrocytes identified markedly elevated glutathione (GSH) concentrations as a candidate mediator of urate's astrocyte-dependent neuroprotective effects. Urate treatment also induced the nuclear translocation of the nuclear factor (erythroid-derived 2)-like 2 (Nrf2) protein and transcriptional activation of its key target genes in primary astrocytic cultures. Urate's neuroprotective effect was attenuated when GSH was depleted in the conditioned media either by targeting its synthesis or release by astrocytes. Overall, these results implicate GSH as the extracellular astrocytic factor mediating the protective effect of urate in a cellular model of PD. These results also show that urate can employ a novel indirect neuroprotective mechanism via induction of the Nrf2 signaling pathway, a master regulator of the response to oxidative stress, in astrocytes.


Assuntos
Astrócitos/efeitos dos fármacos , Astrócitos/metabolismo , Glutationa/metabolismo , Fármacos Neuroprotetores/farmacologia , Ácido Úrico/farmacologia , Transporte Ativo do Núcleo Celular/efeitos dos fármacos , Transporte Ativo do Núcleo Celular/fisiologia , Animais , Células Cultivadas , Córtex Cerebral/efeitos dos fármacos , Córtex Cerebral/metabolismo , Meios de Cultivo Condicionados , Avaliação Pré-Clínica de Medicamentos , Camundongos , Fator 2 Relacionado a NF-E2/metabolismo , Transdução de Sinais/efeitos dos fármacos
10.
J Alzheimers Dis ; 98(4): 1319-1328, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38517790

RESUMO

Background: The literature presents conflicting results regarding the potential protective effect of prevalent cancer on the development of dementia and Alzheimer's disease (AD). Objective: Association between cancer and subsequent risk of dementia and/or AD was reported previously, but survival bias has been of concern. Here, we aimed to calculate the lifetime risk of dementia and AD and evaluate the association of cancer history with these two conditions. Methods: In this retrospective analysis, we included 292,654 participants aged 60+ y during the follow-up and free of dementia at baseline, within the UK Biobank cohort. Lifetime risks of dementia and AD were estimated in individuals with and without cancer history, and different durations of cancer exposure and cancer types. Results: During a median of 12.5 follow-up years, 5,044 new dementia and 2,141 AD cases were reported. Lifetime risks of dementia and AD were lower in cancer survivors compared to those without cancer, and this effect was more pronounced in participants with cancer history exposure≥5 years. Similar relationship was observed in individual cancer types, except for breast cancer. Conclusions: Results suggested an inverse association between cancer history and lifetime risk of dementia and AD, which may be modified by different cancer types and cancer exposure time.


Assuntos
Doença de Alzheimer , Neoplasias , Humanos , Doença de Alzheimer/epidemiologia , Estudos Retrospectivos , Fatores de Risco , Neoplasias/epidemiologia
11.
Parkinsonism Relat Disord ; 119: 105965, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38142631

RESUMO

BACKGROUND: A shared biological component between melanoma and Parkinson's disease (PD) has been suggested. Yet, epidemiological evidence is scarce. OBJECTIVE: To examine the association of hair color and family history of melanoma, two strong predictors of melanoma risk, with the occurrence of PD. METHODS: We followed 131,342 women and men for ∼30 years for the development of PD. We calculated the cumulative incidence of PD from ages 40 to 90 according to hair color, and estimated the hazard ratio of PD according to hair color and family history of melanoma. RESULTS: Hair color was not strongly associated with the risk of PD, especially at advanced ages. In contrast, individuals with a family history of melanoma had a 1.4-fold higher risk of PD compared to those without a history. CONCLUSIONS: Our results support the hypothesis of a shared biological component between PD and melanoma. Both pigmentary and non-pigmentary pathways may play a role.


Assuntos
Melanoma , Doença de Parkinson , Masculino , Humanos , Feminino , Melanoma/epidemiologia , Melanoma/genética , Doença de Parkinson/epidemiologia , Doença de Parkinson/genética , Doença de Parkinson/complicações , Cor de Cabelo/genética , Incidência , Fatores de Risco
12.
J Neurosci ; 32(33): 11299-308, 2012 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-22895713

RESUMO

Mesencephalic dopamine neurons are central to many aspects of human cognition, motivational, and motor behavior, and they are uniquely vulnerable to degenerative neurologic disorders such as Parkinson's disease. There is growing evidence that in the mature brain these neurons not only remain responsive to neurotrophic support, but are dependent on it for viability and function. Little is known of the cellular signaling pathways that mediate this support, although some evidence suggests that protein kinase Akt/PKB may play such a role. Another candidate for such a role is serum- and glucocorticoid-inducible kinase (SGK), a member of the AGC kinase family that is closely related to Akt. We have herein examined the responsiveness of adult mouse dopamine neurons in vivo to overexpression of wild-type and a constitutively active form of SGK by use of viral vector transfer in normal mice and both before and after 6-OHDA lesion. We find that SGK induces a broad spectrum of neurotrophic effects on these neurons, including induction of neuronal hypertrophy, protection from both neuron death and neurotoxin-induced retrograde axonal degeneration, and axon regeneration. Given the diverse and robust effects of SGK on these neurons, and its abundant expression in them, we suggest that SGK, like closely related Akt, may play a role in their responsiveness to neurotrophic factors and in adult maintenance. It therefore offers a novel target for therapeutic development.


Assuntos
Neurônios Dopaminérgicos/enzimologia , Regulação Enzimológica da Expressão Gênica/fisiologia , Proteínas Imediatamente Precoces/metabolismo , Mesencéfalo/citologia , Proteínas Serina-Treonina Quinases/metabolismo , Animais , Contagem de Células , Morte Celular/efeitos dos fármacos , Morte Celular/genética , Neurônios Dopaminérgicos/efeitos dos fármacos , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Vetores Genéticos/fisiologia , Proteínas de Fluorescência Verde/genética , Proteínas Imediatamente Precoces/genética , Masculino , Feixe Prosencefálico Mediano/citologia , Feixe Prosencefálico Mediano/efeitos dos fármacos , Mesencéfalo/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Mutação/genética , Degeneração Neural/induzido quimicamente , Degeneração Neural/metabolismo , Oxidopamina/toxicidade , Fosfopiruvato Hidratase/metabolismo , Proteínas Serina-Treonina Quinases/genética , RNA Mensageiro/metabolismo , Estatísticas não Paramétricas , Simpatolíticos/toxicidade , Transdução Genética/métodos , Tirosina 3-Mono-Oxigenase/genética , Tirosina 3-Mono-Oxigenase/metabolismo
13.
Biomed Chromatogr ; 27(1): 122-9, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22674671

RESUMO

The purine metabolic pathway has been implicated in neurodegeneration and neuroprotection. High-performance liquid chromatography (HPLC) is widely used to determine purines and metabolites. However, methods for analysis of multiple purines in a single analysis have not been standardized, especially in brain tissue. We report the development and validation of a reversed-phase HPLC method combining electrochemical and UV detection after a short gradient run to measure seven purine metabolites (adenosine, guanosine, inosine, guanine, hypoxanthine, xanthine and urate) from the entire purine metabolic pathway. The limit of detection (LoD) for each analyte was determined. The LoD using UV absorption was 0.001 mg/dL for hypoxanthine (Hyp), inosine (Ino), guanosine (Guo) and adenosine (Ado), and those using coulometric electrodes were 0.001 mg/dL for guanine (Gua), 0.0001 mg/dL for urate (UA) and 0.0005 mg/dL for xanthine (Xan). The intra- and inter-day coefficient of variance was generally <8%. Using this method, we determined basal levels of these metabolites in mouse brain and serum, as well as in post-mortem human brain. Peak identities were confirmed by enzyme degradation. Spike recovery was performed to assess accuracy. All recoveries fell within 80-120%. Our HPLC method provides a sensitive, rapid, reproducible and low-cost method for determining multiple purine metabolites in a single analysis in serum and brain specimens.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Corpo Estriado/química , Purinas/análise , Animais , Técnicas Eletroquímicas , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Purinas/sangue , Purinas/química , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Espectrofotometria Ultravioleta
14.
Neural Regen Res ; 18(7): 1613-1622, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36571370

RESUMO

Activating V600E in v-Raf murine sarcoma viral oncogene homolog B (BRAF) is a common driver mutation in cancers of multiple tissue origins, including melanoma and glioma. BRAFV600E has also been implicated in neurodegeneration. The present study aims to characterize BRAFV600E during cell death and proliferation of three major cell types of the central nervous system: neurons, astrocytes, and microglia. Multiple primary cultures (primary cortical mixed culture) and cell lines of glial cells (BV2) and neurons (SH-SY5Y) were employed. BRAFV600E and BRAFWT expression was mediated by lentivirus or retrovirus. Blockage of downstream effectors (extracellular signal-regulated kinase 1/2 and JNK1/2) were achieved by siRNA. In astrocytes and microglia, BRAFV600E induces cell proliferation, and the proliferative effect in microglia is mediated by activated extracellular signal-regulated kinase, but not c-Jun N-terminal kinase. Conditioned medium from BRAFV600E-expressing microglia induced neuronal death. In neuronal cells, BRAFV600E directly induces neuronal death, through c-Jun N-terminal kinase but not extracellular signal-regulated kinase. We further show that BRAF-related genes are enriched in pathways in patients with Parkinson's disease. Our study identifies distinct consequences mediated by distinct downstream effectors in dividing glial cells and in neurons following the same BRAF mutational activation and a causal link between BRAF-activated microglia and neuronal cell death that does not require physical proximity. It provides insight into a possibly important role of BRAF in neurodegeneration as a result of either dysregulated BRAF in neurons or its impact on glial cells.

15.
Patterns (N Y) ; 4(11): 100877, 2023 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-38035187

RESUMO

In their recent publication in Patterns, the authors proposed a novel multi-scale unified mobility model to capture the universal-scale laws of individual and population movement within urban agglomerations. This People of Data highlights the contributions of their work to the field and the critical role data science plays in research and the research community.

16.
Patterns (N Y) ; 4(11): 100862, 2023 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-38035194

RESUMO

Understanding human mobility patterns is vital for the coordinated development of cities in urban agglomerations. Existing mobility models can capture single-scale travel behavior within or between cities, but the unified modeling of multi-scale human mobility in urban agglomerations is still analytically and computationally intractable. In this study, by simulating people's mental representations of physical space, we decompose and model the human travel choice process as a cascaded multi-class classification problem. Our multi-scale unified model, built upon cascaded deep neural networks, can predict human mobility in world-class urban agglomerations with thousands of regions. By incorporating individual memory features and population attractiveness features extracted by a graph generative adversarial network, our model can simultaneously predict multi-scale individual and population mobility patterns within urban agglomerations. Our model serves as an exemplar framework for reproducing universal-scale laws of human mobility across various spatial scales, providing vital decision support for urban settings of urban agglomerations.

17.
PLoS One ; 18(1): e0280162, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36649222

RESUMO

This paper proposes a random-effect spatial OD (origin-destination) dependence model to investigate varying trip distributions over time. By proposing a maximum likelihood estimation with spectral decomposition methods, the effects of spatial dependences and the unobservable zonal heterogeneity at the origin and destination can be estimated simultaneously. A series of numerical experiments and a real-world trip distribution study with cellular signaling data collected in Hangzhou, China, are conducted. This paper enriches the existing literature by developing (1) an innovative specification to allow for random effects in existing spatial OD dependence models; (2) an innovative estimation method to obtain the values of parameters and improve model fittings; and (3) a set of numerical experiments and an empirical trip distribution analysis that jointly captures spatial effects (spatial interaction and spatial OD dependences), and the unobservable zonal heterogeneity. This paper can equip policymakers with an effective tool for analyzing the OD travel flow over time which is a groundwork for making appropriate transportation policies.


Assuntos
Modelos Teóricos , Viagem , Análise Espacial , China
18.
Res Sq ; 2023 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-37398302

RESUMO

Background: Melanocortin 1 receptor (MC1R) is a key pigmentation gene, and loss-of-function of MC1R variants that produce red hair may be associated with Parkinson's disease (PD). We previously reported compromised dopaminergic neuron survival in Mc1r mutant mice and dopaminergic neuroprotective effects of local injection of a MC1R agonist to the brain or a systemically administered MC1R agonist with appreciable CNS permeability. Beyond melanocytes and dopaminergic neurons, MC1R is expressed in other peripheral tissues and cell types, including immune cells. The present study investigates the impact of NDP-MSH, a synthetic melanocortin receptor (MCR) agonist that does not cross BBB, on the immune system and the nigrostriatal dopaminergic system in mouse model of PD. Methods: C57BL/6 mice were treated systemically with MPTP.HCl (20 mg/kg) and LPS (1 mg/kg) from day 1 to day 4 and NDP-MSH (400 µg/kg) or vehicle from day 1 to day 12 following which the mice were sacrificed. Peripheral and CNS immune cells were phenotyped and inflammatory markers were measured. The nigrostriatal dopaminergic system was assessed behaviorally, chemically, immunologically, and pathologically. To understand the role of regulatory T cells (Tregs) in this model, CD25 monoclonal antibody was used to deplete CD25+ Tregs. Results: Systemic NDP-MSH administration significantly attenuated striatal dopamine depletion and nigral dopaminergic neuron loss induced by MPTP+LPS. It improved the behavioral outcomes in the pole test. Mc1r mutant mice injected with NDP-MSH in the MPTP and LPS paradigm showed no changes in striatal dopamine levels suggesting that the NDP-MSH acts through the MC1R pathway. Although no NDP-MSH was detected in the brain, peripheral, NDP-MSH attenuated neuroinflammation as observed by diminished microglial activation in the nigral region, along with reduced TNF-α and IL1ß levels in the ventral midbrain. Depletion of Tregs limited the neuroprotective effects of NDP-MSH. Conclusions: Our study demonstrates that peripherally acting NDP-MSH confers protection on dopaminergic nigrostriatal neurons and reduces hyperactivated microglia. NDP-MSH modulates peripheral immune responses, and Tregs may be involved in the neuroprotective effect of NDP-MSH.

19.
J Neuroimmune Pharmacol ; 18(4): 704-717, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-38110615

RESUMO

BACKGROUND: Melanocortin 1 receptor (MC1R) is a key pigmentation gene, and loss-of-function of MC1R variants that produce red hair may be associated with Parkinson's disease (PD). We previously reported compromised dopaminergic neuron survival in Mc1r mutant mice and dopaminergic neuroprotective effects of local injection of a MC1R agonist to the brain or a systemically administered MC1R agonist with appreciable central nervous system (CNS) permeability. Beyond melanocytes and dopaminergic neurons, MC1R is expressed in other peripheral tissues and cell types, including immune cells. The present study investigates the impact of NDP-MSH, a synthetic melanocortin receptor (MCR) agonist that does not cross BBB, on the immune system and the nigrostriatal dopaminergic system in mouse model of PD. METHODS: C57BL/6 mice were treated systemically with MPTP.HCl (20 mg/kg) and LPS (1 mg/kg) from day 1 to day 4 and NDP-MSH (400 µg/kg) or vehicle from day 1 to day 12 following which the mice were sacrificed. Peripheral and CNS immune cells were phenotyped and inflammatory markers were measured. The nigrostriatal dopaminergic system was assessed behaviorally, chemically, immunologically, and pathologically. To understand the role of regulatory T cells (Tregs) in this model, CD25 monoclonal antibody was used to deplete CD25 + Tregs. RESULTS: Systemic NDP-MSH administration significantly attenuated striatal dopamine depletion and nigral dopaminergic neuron loss induced by MPTP + LPS. It improved the behavioral outcomes in the pole test. Mc1r mutant mice injected with NDP-MSH in the MPTP and LPS paradigm showed no changes in striatal dopamine levels suggesting that the NDP-MSH acts through the MC1R pathway. Although no NDP-MSH was detected in the brain, peripheral, NDP-MSH attenuated neuroinflammation as observed by diminished microglial activation in the nigral region, along with reduced TNF-α and IL1ß levels in the ventral midbrain. Depletion of Tregs was associated with diminished neuroprotective effects of NDP-MSH. CONCLUSIONS: Our study demonstrates that peripherally acting NDP-MSH confers protection on dopaminergic nigrostriatal neurons and reduces hyperactivated microglia. NDP-MSH modulates peripheral immune responses, and Tregs may be involved in the neuroprotective effect of NDP-MSH.


Assuntos
Fármacos Neuroprotetores , Doença de Parkinson , Camundongos , Animais , Doença de Parkinson/tratamento farmacológico , Receptor Tipo 1 de Melanocortina/genética , Receptor Tipo 1 de Melanocortina/metabolismo , Dopamina/farmacologia , Fármacos Neuroprotetores/farmacologia , Lipopolissacarídeos/farmacologia , Camundongos Endogâmicos C57BL , Imunidade , Neurônios Dopaminérgicos , Modelos Animais de Doenças
20.
Sci Rep ; 13(1): 14548, 2023 09 04.
Artigo em Inglês | MEDLINE | ID: mdl-37666916

RESUMO

Autonomic symptoms (AS) are critical in Parkinson's disease (PD). We aimed to determine the relative significance of clinical factors allowing predictions about incidence of AS, and examine AS profiles among PD patients by motor subtype and its relation to AS. The cross-sectional data of a multicentre sample, including 714 PD patients and 194 healthy controls from Parkinson's Progression Marker Initiative study and Pingchan granule study were analyzed, stratified by PD subtypes [postural instability and gait disturbances (PIGD), tremor dominant (TD), and indeterminate] and domain autonomic dysfunction. Compared with healthy controls, PD patients scored higher in the total Scales for Outcomes in Parkinson's Disease-Autonomic dysfunction score and in several domain scores in particular, and there was a significant overlap in domain AS. Risk factors of individual domain autonomic dysfunction were heterogeneous. PIGD and indeterminate were the predominant subtypes in pupillomotor and thermoregulatory symptoms. TD and indeterminate were more likely to suffer from cardiovascular problem. The odd in sexual dysfunction was significant for PIGD. Gastrointestinal and urinary symptoms seemed not to be associated with a specific subtype. Our study demonstrated that AS were highly heterogeneous and 3 subtypes differed in autonomic performance, providing clues to understand mechanisms underlying AS in PD.


Assuntos
Doença de Parkinson , Disautonomias Primárias , Humanos , Estudos Transversais , Tremor , Sistema Nervoso Autônomo
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