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1.
Psychiatry Investig ; 21(6): 610-617, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38960438

RESUMO

OBJECTIVE: Increased fast food consumption can have adverse effects on health and well-being among adolescents, posing a significant public health concern. The school closures due to the coronavirus disease-2019 (COVID-19) pandemic have led to changes in eating patterns and disrupted a balance diet among adolescents. This study explored the factors associated with fast food consumption among adolescents during school closures due to the COVID-19 pandemic. METHODS: A total of 1,710 middle and high school students in Gwangju, South Korea participated in a cross-sectional survey. The self-administered questionnaire included items assessing dietary intake, physical activity, sleep, media use, and sociodemographic information. The Patient Health Questonnaire-9, Generalized Anxiety Disorder-7, and three item version of the UCLA Loneliness Scale were also administered. Multivariable logistic regression was used to examine the factors associated with increased fast food consumption. RESULTS: Approximately 34.6% of the surveyed adolescents reported increased fast food consumption during school closures, as well as increased sleep duration, increased sedentary behaviors including watching TV and using the internet, and reduced physical activity. Multivariable logistic regression analysis revealed that fast food consumption during school closures was associated with irregular patterns of main meals and sleep, decreased physical activity, increased internet use, and a lack of daytime adult supervision. CONCLUSION: Our results highlight the need for dietary and lifestyle monitoring and guidelines to promote health among adolescents, especially during school closures. In conclusion, nutrition intervention programs aiming to limit fast food consumption and enhance healthy dietary habits among adolescents during long-term school closures are warranted.

2.
J Control Release ; 367: 768-778, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38341178

RESUMO

Immunotherapy based on adoptive transfer of natural killer (NK) cells is a promising strategy for circumventing the limitations of cancer treatments. However, components of the immunosuppressive tumor microenvironment (TME), such as transforming growth factor-beta (TGF-ß), compromise the therapeutic efficacy of NK cells significantly. To address these limitations, we developed a novel method of engineering NK cells for adaptive transfer. The method is based on nanogels that serve two functions: (1) they overcome the TGF-ß-mediated stress environment of the TME, and (2) they enhance the direct anti-tumor activity of NK cells. Previously, we demonstrated that cationic compounds such as 25 K branched polyethylenimine (25 K bPEI) prime NK cells, putting them in a 'ready-to-fight' state. Based on these findings, we designed nanogels that have two primary characteristics: (1) they encapsulate galunisertib (Gal), which is used clinically to inhibit TGF-ß receptor activity, thereby blocking TGF-ß signaling; and (2) they provide cells with a surface coating of 25 K bPEI. When grown in culture medium containing TGF-ß, nanogel-treated NK cells demonstrated greater migration ability, degranulation activity, and cytotoxicity towards cancer cells than untreated NK cells. Additionally, the in vivo efficacy of nanogel-treated NK cells against PC-3 xenografts was significantly greater than that of Chem_NK cells primed by 25 K bPEI alone. These findings suggest that Gal-loaded 25 K bPEI-coated nanogels exert anti-tumor effects via chemical priming, as well suppressing the effects of TGF-ß on NK cells. We also expect 25 K bPEI-based nanogels to have great potential to overcome the suppressive effects of the TME through their NK cell-priming activity and delivery of the desired chemicals.


Assuntos
Citotoxicidade Imunológica , Polietilenoglicóis , Polietilenoimina , Fator de Crescimento Transformador beta , Humanos , Nanogéis , Fator de Crescimento Transformador beta/farmacologia , Linhagem Celular Tumoral , Células Matadoras Naturais , Microambiente Tumoral
3.
Front Psychiatry ; 15: 1289850, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38283846

RESUMO

Periventricular heterotopia (PH) is a developmental malformation in the brain. Because the clinical symptoms are heterogeneous, few studies have investigated the psychiatric symptoms associated with PH. We describe the case of a 17-year-old male with bipolar disorder (BD), who had been treated for attention deficit-hyperactivity disorder (ADHD) and developmental delay in childhood. He had experienced depression for 1 year and was admitted to the emergency room following a suicide attempt. He was admitted to the psychiatric ward for further evaluation and treatment for elated mood, decreased need for sleep, increased sexuality, and delusion. The patient was diagnosed with BP-I disorder and PH via brain magnetic resonance imaging. After combined treatment with valproic acid and aripiprazole, his manic symptoms stabilized. To our knowledge, this is the first report of an adolescent PH case with a history of early onset BD and ADHD in childhood.

4.
J Vet Med Sci ; 85(10): 1116-1120, 2023 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-37661431

RESUMO

A 15-year-old, spayed female, Scottish Straight cat without any traumatic history was presented with swollen abdomen and diagnosed as an abdominal wall hernia. Abdominal ultrasound revealed thickened, irregular, and hypoechoic change of abdominal wall muscle adjacent to defect. During the herniorrhaphy, multiple nodules were identified in the subcutaneous tissue around the defect. Histological examination of the nodular tissue was performed, and it was confirmed as mammary gland tumor. After the surgery, metastatic changes of the pancreas were identified, and pleural effusion and ascites were also confirmed. The patient deteriorated rapidly and died 78 days after the surgery. This is the first case presenting abdominal wall hernia induced by malignant tumor in veterinary medicine.


Assuntos
Parede Abdominal , Carcinoma , Doenças do Gato , Hérnia Abdominal , Hérnia Ventral , Glândulas Mamárias Humanas , Gatos , Animais , Feminino , Humanos , Hérnia Abdominal/diagnóstico por imagem , Hérnia Abdominal/cirurgia , Hérnia Abdominal/veterinária , Hérnia Ventral/cirurgia , Hérnia Ventral/veterinária , Parede Abdominal/cirurgia , Herniorrafia/veterinária , Carcinoma/cirurgia , Carcinoma/veterinária , Doenças do Gato/diagnóstico por imagem , Doenças do Gato/cirurgia
5.
Adv Sci (Weinh) ; 9(13): e2103950, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35138051

RESUMO

Water, abundant and ubiquitous in nature, is an easy yet powerful resource for the creatures to survive by putting together with their topologies interfacing their living environment. Here, a slippery, water-infusing surface (SWIS) that retains a thick and stable water layer on the membrane is presented, robustly maintaining the oil repellency against the pressure and friction of immiscible liquids. Inspired by the plant trichome structures and their function, grooved nanotrichome, formed on the fibrous membrane by the oxygen plasma etching, induces robust water lubrication on the SWIS. SWIS membrane repels and separates highly viscous and adhesive oils in air and underwater by preventing oils from adhering to the lubricating surface. Repeated tests both in air and underwater confirm the antiadhesion and self-cleaning properties of the SWIS. The SWIS oil scooper, fixed on a frame with a handle, successfully collects spilled oil on a pilot-scale oil spill site and a real ocean oil spill site by simply scooping and recovering the oil. In addition, SWIS membrane is expected to help protect environments with further applications such as oil-wastewater treatment and oil separation in food.


Assuntos
Purificação da Água , Água , Lubrificantes , Lubrificação , Óleos/química , Água/química
6.
J Hazard Mater ; 410: 124549, 2021 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-33250313

RESUMO

The pitcher plant has evolved its hierarchically grooved peristome to enhance a water-based slippery system for capturing insects with oil-covered footpads. Based on this, we proposed a hierarchically porous oil scoop (HPOS) with capillary-induced oil peel-off ability for repeatable spilled oil recovery. As the HPOS scoops oil-water mixture, water passes through the hole while the oil is confined within a curved geometry. The filter in HPOS has three levels of porous structures; (1) 3D-printed mesh structure with sub-millimeter scale hole to filter out oil from an oil-water mixture, (2) internal micropore in fibers enhancing capillarity and water transport, (3) O2 plasma-induced high-aspect-ratio nanopillar structures imposing anti-oil-fouling property with capillary-induced oil peeling. As the oil-contaminated HPOS makes contact with water, water meniscus rises and peels off the oil immediately at the air-water interface. The oil-peel-off ability of the HPOS would prevent pores from clogging by oils for reuse. The study demonstrated that the HPOS recovers highly viscous oil (up to 5000 mm2·s-1) with a high recovery rate (>95%), leaving the filtered water with low oil content (<10 ppm), which satisfies the discharge criterion of 15 ppm.

7.
PLoS Biol ; 17(2): e3000134, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30735499

RESUMO

Microglia are resident immune cells that play critical roles in maintaining the normal physiology of the central nervous system (CNS). Remarkably, microglia have an intrinsic capacity to repopulate themselves after acute ablation. However, the underlying mechanisms that drive such restoration remain elusive. Here, we characterized microglial repopulation both spatially and temporally following removal via treatment with the colony stimulating factor 1 receptor (CSF1R) inhibitor PLX5622. We show that microglia were replenished via self-renewal, with no contribution from nonmicroglial lineages, including Nestin+ progenitors and the circulating myeloid population. Interestingly, spatial analyses with dual-color labeling revealed that newborn microglia recolonized the parenchyma by forming distinctive clusters that maintained stable territorial boundaries over time, indicating the proximal expansive nature of adult microgliogenesis and the stability of microglia tiling. Temporal transcriptome profiling at different repopulation stages revealed that adult newborn microglia gradually regain steady-state maturity from an immature state that is reminiscent of the neonatal stage and follow a series of maturation programs, including nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) activation, interferon immune activation, and apoptosis. Importantly, we show that the restoration of microglial homeostatic density requires NF-κB signaling as well as apoptotic egress of excessive cells. In summary, our study reports key events that take place from microgliogenesis to homeostasis reestablishment.


Assuntos
Envelhecimento/genética , Encéfalo/metabolismo , Homeostase/genética , Microglia/metabolismo , NF-kappa B/genética , Receptores de Fator Estimulador das Colônias de Granulócitos e Macrófagos/genética , Envelhecimento/metabolismo , Animais , Animais Recém-Nascidos , Apoptose/efeitos dos fármacos , Apoptose/genética , Encéfalo/citologia , Encéfalo/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Interferons/genética , Interferons/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Microglia/citologia , Microglia/efeitos dos fármacos , NF-kappa B/metabolismo , Nestina/genética , Nestina/metabolismo , Células-Tronco Neurais/citologia , Células-Tronco Neurais/metabolismo , Neurogênese/efeitos dos fármacos , Neurogênese/genética , Compostos Orgânicos/toxicidade , Receptores de Fator Estimulador das Colônias de Granulócitos e Macrófagos/antagonistas & inibidores , Receptores de Fator Estimulador das Colônias de Granulócitos e Macrófagos/metabolismo , Receptores do Fator de Crescimento Derivado de Plaquetas/genética , Receptores do Fator de Crescimento Derivado de Plaquetas/metabolismo , Regeneração/genética , Transdução de Sinais , Transcriptoma
8.
Eur J Med Chem ; 164: 517-545, 2019 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-30622025

RESUMO

Hydantoin, imidazolidine-2,4-dione, is a non-aromatic five-membered heterocycle, which is considered a valuable, privileged scaffold in medicinal chemistry. The importance of the hydantoin scaffold in drug discovery has been reinforced by several medicines in clinical use, such as phenytoin, nitrofurantoin, and enzalutamide. Hydantoin has five potential substituent sites, including two hydrogen bond acceptors and two hydrogen bond donors. Two additional attractive features of hydantoin scaffolds are their synthetic feasibility for core scaffolds via established cyclization reactions and their ease of accepting various substituents. Because of these characteristics, many hydantoin derivatives with different substituents have been designed and synthesized and exhibit a broad spectrum of biological and pharmacological activities against, for example, cancers, microbial infections, metabolic diseases, and epilepsy. In this review, recent contributions of hydantoin, thiohydantoin, and selenohydantoin scaffolds to medicinal chemistry are described; some major compounds are presented to emphasize their importance, and their structure-activity relationships (SARs) are briefly addressed. Major discussions are devoted to the structural features or novelty of each scaffold and its SAR. The publications in this review encompass those from 2012 to 2018.


Assuntos
Química Farmacêutica/métodos , Hidantoínas/uso terapêutico , Tioidantoínas/uso terapêutico , Animais , Humanos , Selênio , Relação Estrutura-Atividade
9.
J Neurosci ; 35(2): 807-18, 2015 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-25589773

RESUMO

Aging is the predominant risk factor for neurodegenerative diseases. One key phenotype as the brain ages is an aberrant innate immune response characterized by proinflammation. However, the molecular mechanisms underlying aging-associated proinflammation are poorly defined. Whether chronic inflammation plays a causal role in cognitive decline in aging and neurodegeneration has not been established. Here we report a mechanistic link between chronic inflammation and aging microglia and a causal role of aging microglia in neurodegenerative cognitive deficits. We showed that SIRT1 is reduced with the aging of microglia and that microglial SIRT1 deficiency has a causative role in aging- or tau-mediated memory deficits via IL-1ß upregulation in mice. Interestingly, the selective activation of IL-1ß transcription by SIRT1 deficiency is likely mediated through hypomethylating the specific CpG sites on IL-1ß proximal promoter. In humans, hypomethylation of IL-1ß is strongly associated with chronological age and with elevated IL-1ß transcription. Our findings reveal a novel epigenetic mechanism in aging microglia that contributes to cognitive deficits in aging and neurodegenerative diseases.


Assuntos
Envelhecimento/metabolismo , Cognição , Epigênese Genética , Interleucina-1beta/metabolismo , Microglia/metabolismo , Sirtuína 1/metabolismo , Animais , Estudos de Casos e Controles , Metilação de DNA , Humanos , Interleucina-1beta/genética , Camundongos , Sirtuína 1/deficiência , Sirtuína 1/genética , Tauopatias/metabolismo , Regulação para Cima
10.
Front Aging Neurosci ; 5: 53, 2013 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-24093018

RESUMO

Silent information regulator 2 proteins (sirtuins or SIRTs) are a group of deacetylases (or deacylases) whose activities are dependent on and regulated by nicotinamide adenine dinucleotide (NAD(+)). Compelling evidence supports that sirtuins play major roles in many aspects of physiology, especially in pathways related to aging - the predominant and unifying risk factor for neurodegenerative diseases. In this review, we highlight the molecular mechanisms underlying the protective effects of sirtuins in neurodegenerative diseases, focusing on protein homeostasis, neural plasticity, mitochondrial function, and sustained chronic inflammation. We will also examine the potential and challenges of targeting sirtuin pathways to block these pathogenic pathways.

11.
J Neuroinflammation ; 8: 152, 2011 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-22051244

RESUMO

BACKGROUND: Amyloid ß (Aß) accumulates in Alzheimer's disease (AD) brain. Microglial activation also occurs in AD, and this inflammatory response may contribute to disease progression. Microglial activation can be induced by Aß, but the mechanisms by which this occurs have not been defined. The nuclear enzyme poly(ADP-ribose) polymerase-1 (PARP-1) regulates microglial activation in response to several stimuli through its interactions with the transcription factor, NF-κB. The purpose of this study was to evaluate whether PARP-1 activation is involved in Aß-induced microglial activation, and whether PARP-1 inhibition can modify microglial responses to Aß. METHODS: hAPP(J20) mice, which accumulate Aß with ageing, were crossed with PARP-1(-/-) mice to assess the effects of PARP-1 depletion on microglial activation, hippocampal synaptic integrity, and cognitive function. Aß peptide was also injected into brain of wt and PARP-1(-/-) mice to directly determine the effects of PARP-1 on Aß-induced microglial activation. The effect of PARP-1 on Aß-induced microglial cytokine production and neurotoxicity was evaluated in primary microglia cultures and in microglia-neuron co-cultures, utilizing PARP-1(-/-) cells and a PARP-1 inhibitor. NF-κB activation was evaluated in microglia infected with a lentivirus reporter gene. RESULTS: The hAPP(J20) mice developed microglial activation, reduced hippocampal CA1 calbindin expression, and impaired novel object recognition by age 6 months. All of these features were attenuated in hAPP(J20)/PARP-1(-/-) mice. Similarly, Aß(1-42) injected into mouse brain produced a robust microglial response in wild-type mice, and this was blocked in mice lacking PARP-1 expression or activity. Studies using microglial cultures showed that PARP-1 activity was required for Aß-induced NF-κB activation, morphological transformation, NO release, TNFα release, and neurotoxicity. Conversely, PARP-1 inhibition increased release of the neurotrophic factors TGFß and VEGF, and did not impair microglial phagocytosis of Aß peptide. CONCLUSIONS: These results identify PARP-1 as a requisite and previously unrecognized factor in Aß-induced microglial activation, and suggest that the effects of PARP-1 are mediated, at least in part, by its interactions with NF-κB. The suppression of Aß-induced microglial activation and neurotoxicity by PARP-1 inhibition suggests this approach could be useful in AD and other disorders in which microglial neurotoxicity may contribute.


Assuntos
Peptídeos beta-Amiloides/farmacologia , Microglia/efeitos dos fármacos , Microglia/metabolismo , Poli(ADP-Ribose) Polimerases/metabolismo , Peptídeos beta-Amiloides/genética , Peptídeos beta-Amiloides/metabolismo , Animais , Comportamento Animal/efeitos dos fármacos , Calbindinas , Células Cultivadas , Técnicas de Cocultura , Citocinas/metabolismo , Hipocampo/citologia , Hipocampo/metabolismo , Memória/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Microglia/citologia , NF-kappa B/metabolismo , Neurônios/citologia , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Fagocitose/efeitos dos fármacos , Poli(ADP-Ribose) Polimerase-1 , Poli(ADP-Ribose) Polimerases/genética , Proteína G de Ligação ao Cálcio S100/genética , Proteína G de Ligação ao Cálcio S100/metabolismo
12.
J Biol Chem ; 286(37): 32713-22, 2011 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-21771791

RESUMO

Aberrant microglial activation has been proposed to contribute to the cognitive decline in Alzheimer disease (AD), but the underlying molecular mechanisms remain enigmatic. Fractalkine signaling, a pathway mediating the communication between microglia and neurons, is deficient in AD brains and down-regulated by amyloid-ß. Although fractalkine receptor (CX3CR1) on microglia was found to regulate plaque load, no functional effects have been reported. Our study demonstrates that CX3CR1 deficiency worsens the AD-related neuronal and behavioral deficits. The effects were associated with cytokine production but not with plaque deposition. Ablation of CX3CR1 in mice overexpressing human amyloid precursor protein enhanced Tau pathology and exacerbated the depletion of calbindin in the dentate gyrus. The levels of calbindin in the dentate gyrus correlated negatively with those of tumor necrosis factor α and interleukin 6, suggesting neurotoxic effects of inflammatory factors. Functionally, removing CX3CR1 in human amyloid precursor protein mice worsened the memory retention in passive avoidance and novel object recognition tests, and their memory loss in the novel object recognition test is associated with high levels of interleukin 6. Our findings identify CX3CR1 as a key microglial pathway in protecting against AD-related cognitive deficits that are associated with aberrant microglial activation and elevated inflammatory cytokines.


Assuntos
Doença de Alzheimer/metabolismo , Transtornos Cognitivos/metabolismo , Microglia/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Receptores de Quimiocinas/metabolismo , Transdução de Sinais , Doença de Alzheimer/genética , Doença de Alzheimer/patologia , Precursor de Proteína beta-Amiloide/genética , Precursor de Proteína beta-Amiloide/metabolismo , Animais , Receptor 1 de Quimiocina CX3C , Calbindinas , Transtornos Cognitivos/genética , Transtornos Cognitivos/patologia , Citocinas/genética , Citocinas/metabolismo , Giro Denteado/metabolismo , Giro Denteado/patologia , Modelos Animais de Doenças , Humanos , Camundongos , Camundongos Knockout , Microglia/patologia , Proteínas do Tecido Nervoso/genética , Receptores de Quimiocinas/genética , Proteína G de Ligação ao Cálcio S100/genética , Proteína G de Ligação ao Cálcio S100/metabolismo
13.
Neuron ; 67(6): 953-66, 2010 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-20869593

RESUMO

Neurodegenerative tauopathies characterized by hyperphosphorylated tau include frontotemporal dementia and Parkinsonism linked to chromosome 17 (FTDP-17) and Alzheimer's disease (AD). Reducing tau levels improves cognitive function in mouse models of AD and FTDP-17, but the mechanisms regulating the turnover of pathogenic tau are unknown. We found that tau is acetylated and that tau acetylation prevents degradation of phosphorylated tau (p-tau). We generated two antibodies specific for acetylated tau and showed that tau acetylation is elevated in patients at early and moderate Braak stages of tauopathy. Histone acetyltransferase p300 was involved in tau acetylation and the class III protein deacetylase SIRT1 in deacetylation. Deleting SIRT1 enhanced levels of acetylated-tau and pathogenic forms of p-tau, probably by blocking proteasome-mediated degradation. Inhibiting p300 with a small molecule promoted tau deacetylation and eliminated p-tau associated with tauopathy. Modulating tau acetylation could be a new therapeutic strategy to reduce tau-mediated neurodegeneration.


Assuntos
Tauopatias/etiologia , Tauopatias/metabolismo , Proteínas tau/metabolismo , Acetilação/efeitos dos fármacos , Análise de Variância , Animais , Animais Recém-Nascidos , Carbazóis/farmacologia , Células Cultivadas , Córtex Cerebral/citologia , Cicloeximida/farmacologia , Modelos Animais de Doenças , Inibidores Enzimáticos/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Imunoprecipitação/métodos , Camundongos , Camundongos Transgênicos , Modelos Biológicos , Mutação/genética , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Fosforilação/efeitos dos fármacos , Fosforilação/fisiologia , Inibidores da Síntese de Proteínas/farmacologia , Ratos , Ratos Sprague-Dawley , Sirtuína 1/genética , Sirtuína 1/metabolismo , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Tauopatias/genética , Fatores de Tempo , Transfecção/métodos , Ubiquitinação/efeitos dos fármacos , Fatores de Transcrição de p300-CBP/fisiologia , Proteínas tau/genética
14.
J Neurochem ; 109(5): 1483-96, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19457162

RESUMO

Although there is known to be a marked concentration of reactive microglia in the substantia nigra pars compacta (SNpc) of patients with Parkinson's disease (PD), a disorder in which alpha-synuclein plays a key pathogenic role, the specific roles of alpha-synuclein and microglia remains poorly understood. In this study, we investigated the effects of alpha-synuclein and the mechanisms of invasive microglial migration into the SNpc. We show that alpha-synuclein up-regulates the expressions of the cell adhesion molecule CD44 and the cell surface protease membrane-type 1 matrix metalloproteinase through the extracellular regulated kinases 1/2 pathway. These concurrent inductions increased the generation of soluble CD44 to liberate microglia from the surrounding extracellular matrix for migration. The effects of alpha-synuclein were identical in BV-2 murine microglial cells subjected to cDNA transfection and extracellular treatment. These inductions in primary microglial cultures of C57Bl/6 mice were identical to those in BV-2 cells. alpha-Synuclein-induced microglial migration into the SNpc was confirmed in vivo using a 6-hydroxydopamine mouse model of PD. Our data demonstrate a correlation between alpha-synuclein-induced phenotypic changes and microglial migration. With the recruitment of the microglial population into the SNpc during dopaminergic neurodegeneration, alpha-synuclein may play a role in accelerating the pathogenesis of PD.


Assuntos
Movimento Celular/fisiologia , Receptores de Hialuronatos/metabolismo , Metaloproteinase 14 da Matriz/metabolismo , Microglia/fisiologia , Regulação para Cima/fisiologia , alfa-Sinucleína/fisiologia , Animais , Encéfalo/citologia , Movimento Celular/efeitos dos fármacos , Movimento Celular/genética , Transplante de Células/métodos , Células Cultivadas , Meios de Cultivo Condicionados/farmacologia , Modelos Animais de Doenças , Receptores de Hialuronatos/genética , Metaloproteinase 14 da Matriz/genética , Camundongos , Camundongos Endogâmicos C57BL , Proteína Quinase 3 Ativada por Mitógeno/genética , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Quinases de Proteína Quinase Ativadas por Mitógeno/genética , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , Oxidopamina/toxicidade , Doença de Parkinson/etiologia , Doença de Parkinson/metabolismo , Doença de Parkinson/patologia , Doença de Parkinson/cirurgia , RNA Mensageiro/metabolismo , RNA Interferente Pequeno/farmacologia , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/fisiologia , Substância Negra/metabolismo , Substância Negra/cirurgia , Transfecção , Regulação para Cima/efeitos dos fármacos , Regulação para Cima/genética , alfa-Sinucleína/genética
15.
Neuron ; 60(2): 247-57, 2008 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-18957217

RESUMO

Impaired degradation of amyloid beta (Abeta) peptides could lead to Abeta accumulation, an early trigger of Alzheimer's disease (AD). How Abeta-degrading enzymes are regulated remains largely unknown. Cystatin C (CysC, CST3) is an endogenous inhibitor of cysteine proteases, including cathepsin B (CatB), a recently discovered Abeta-degrading enzyme. A CST3 polymorphism is associated with an increased risk of late-onset sporadic AD. Here, we identified CysC as the key inhibitor of CatB-induced Abeta degradation in vivo. Genetic ablation of CST3 in hAPP-J20 mice significantly lowered soluble Abeta levels, the relative abundance of Abeta1-42, and plaque load. CysC removal also attenuated Abeta-associated cognitive deficits and behavioral abnormalities and restored synaptic plasticity in the hippocampus. Importantly, the beneficial effects of CysC reduction were abolished on a CatB null background, providing direct evidence that CysC regulates soluble Abeta and Abeta-associated neuronal deficits through inhibiting CatB-induced Abeta degradation.


Assuntos
Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/metabolismo , Encéfalo/metabolismo , Catepsina B/metabolismo , Cistatina C/genética , Cistatina C/metabolismo , Doença de Alzheimer/genética , Doença de Alzheimer/fisiopatologia , Animais , Encéfalo/fisiopatologia , Predisposição Genética para Doença/genética , Camundongos , Camundongos Knockout , Fragmentos de Peptídeos/metabolismo , Placa Amiloide/genética , Placa Amiloide/metabolismo , Placa Amiloide/patologia , Polimorfismo Genético/genética
16.
FASEB J ; 18(13): 1615-7, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15289452

RESUMO

Though the etiology of Parkinson's disease (PD) remains unclear, alpha-synuclein (alpha-SN) is regarded as a major causative agent of PD. Several lines of evidence indicate that immunological abnormalities are associated with PD for unknown reasons. The present study was performed to assess whether peripheral blood mononuclear cells (PBMCs) show altered alpha-SN expression in PD patients and to identify its functions, which may be related to peripheral immune abnormalities in PD. alpha-SN was found to be expressed more in 151 idiopathic PD (IPD) patients than in 101 healthy controls, who nevertheless showed as age-dependent increases. By in vitro transfection, alpha-SN expression was shown to be correlated with glucocorticoid sensitive apoptosis, possibly caused by the enhanced expression of glucocorticoid receptor (GR), caspase activations (caspase-8, caspase-9), CD95 up-regulation, and reactive oxygen species (ROS) production. An understanding of the correlation between alpha-SN levels and apoptosis in the presence of the coordinated involvement of multiple processes would provide an insight into the molecular basis of the disease. The present study provides a clue that the alpha-SN may be one of the primary causes of the immune abnormalities observed in PD and offers new targets for pharmacotherapeutic intervention.


Assuntos
Apoptose , Regulação da Expressão Gênica , Linfócitos/imunologia , Linfócitos/patologia , Proteínas do Tecido Nervoso/metabolismo , Doença de Parkinson/imunologia , Doença de Parkinson/metabolismo , Estudos de Casos e Controles , Caspases/metabolismo , Células Cultivadas , Ativação Enzimática , Humanos , Linfócitos/enzimologia , Linfócitos/metabolismo , Proteínas do Tecido Nervoso/genética , Doença de Parkinson/genética , Doença de Parkinson/patologia , Espécies Reativas de Oxigênio/metabolismo , Receptores de Glucocorticoides/metabolismo , Sinucleínas , alfa-Sinucleína , Receptor fas/genética , Receptor fas/metabolismo
17.
J Cell Biochem ; 89(4): 837-47, 2003 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-12858348

RESUMO

Retinoic acid (RA) is a well-known regulator of chondrocyte phenotype. RA inhibits chondrogenic differentiation of mesenchymal cells and also causes loss of differentiated chondrocyte phenotype. The present study investigated the mechanisms underlying RA regulation of chondrogenesis. RA treatment in chondrifying mesenchymal cells did not affect precartilage condensation, but blocked progression from precartilage condensation to cartilage nodule formation. This inhibitory effect of RA was independent of protein kinase C and extracellular signal-regulated protein kinase, which are positive and negative regulators of cartilage nodule formation, respectively. The progression from precartilage condensation to cartilage nodule requires downregulation of N-cadherin expression. However, RA treatment caused sustained expression of N-cadherin and its associated proteins including alpha- and beta-catenin suggesting that modulation of expression of these molecules is associated with RA-induced inhibition of chondrogenesis. This hypothesis was supported by the observation that disruption of the actin cytoskeleton by cytochalasin D (CD) blocks RA-induced sustained expression of cell adhesion molecules and overcomes RA-induced inhibition of chondrogenesis. Taken together, our results suggest RA inhibits chondrogenesis by stabilizing cell-to-cell interactions at the post-precartilage condensation stage.


Assuntos
Caderinas/biossíntese , Condrogênese/efeitos dos fármacos , Mesoderma/metabolismo , Tretinoína/farmacologia , Animais , Cartilagem/efeitos dos fármacos , Cartilagem/metabolismo , Células Cultivadas , Embrião de Galinha , Colágeno/análogos & derivados , Colágeno/biossíntese , Citocalasina D/farmacologia , Proteínas do Citoesqueleto/biossíntese , Proteínas do Citoesqueleto/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Flavonoides/farmacologia , Botões de Extremidades , Mesoderma/citologia , Mesoderma/efeitos dos fármacos , Proteínas Quinases Ativadas por Mitógeno/antagonistas & inibidores , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Proteína Quinase C/metabolismo , Proteoglicanas/análise , Transativadores/biossíntese , Transativadores/efeitos dos fármacos , Tretinoína/antagonistas & inibidores , alfa Catenina , beta Catenina
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