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1.
J Biol Chem ; 300(9): 107707, 2024 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-39178947

RESUMO

Chronic exposure to elevated levels of manganese (Mn) may cause a neurological disorder referred to as manganism. The transcription factor REST is dysregulated in several neurodegenerative diseases, such as Alzheimer's disease and Parkinson's disease. REST upregulated tyrosine hydroxylase and induced protection against Mn toxicity in neuronal cultures. In the present study, we investigated if dopaminergic REST plays a critical role in protecting against Mn-induced toxicity in vivo using dopaminergic REST conditional knockout (REST-cKO) mice and REST loxP mice as wild-type (WT) controls. Restoration of REST in the substantia nigra (SN) with neuronal REST AAV vector infusion was performed to further support the role of REST in Mn toxicity. Mice were exposed to Mn (330 µg, intranasal, daily for 3 weeks), followed by behavioral tests and molecular biology experiments. Results showed that Mn decreased REST mRNA/protein levels in the SN-containing midbrain, as well as locomotor activity and motor coordination in WT mice, which were further decreased in REST-cKO mice. Mn-induced mitochondrial insults, such as impairment of fission/fusion and mitophagy, apoptosis, and oxidative stress, in the midbrain of WT mice were more pronounced in REST-cKO mice. However, REST restoration in the SN of REST-cKO mice attenuated Mn-induced neurotoxicity. REST's molecular target for its protection is unclear, but REST attenuated Mn-induced mitochondrial dysregulation, indicating that it is a primary intracellular target for both Mn and REST. These novel findings suggest that dopaminergic REST in the nigrostriatal pathway is critical in protecting against Mn toxicity, underscoring REST as a potential therapeutic target for treating manganism.

2.
J Biol Chem ; 299(7): 104879, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37269951

RESUMO

Chronic manganese (Mn) exposure can lead to manganism, a neurological disorder sharing common symptoms with Parkinson's disease (PD). Studies have shown that Mn can increase the expression and activity of leucine-rich repeat kinase 2 (LRRK2), leading to inflammation and toxicity in microglia. LRRK2 G2019S mutation also elevates LRRK2 kinase activity. Thus, we tested if Mn-increased microglial LRRK2 kinase is responsible for Mn-induced toxicity, and exacerbated by G2019S mutation, using WT and LRRK2 G2019S knock-in mice and BV2 microglia. Mn (30 mg/kg, nostril instillation, daily for 3 weeks) caused motor deficits, cognitive impairments, and dopaminergic dysfunction in WT mice, which were exacerbated in G2019S mice. Mn induced proapoptotic Bax, NLRP3 inflammasome, IL-1ß, and TNF-α in the striatum and midbrain of WT mice, and these effects were more pronounced in G2019S mice. BV2 microglia were transfected with human LRRK2 WT or G2019S, followed by Mn (250 µM) exposure to better characterize its mechanistic action. Mn increased TNF-α, IL-1ß, and NLRP3 inflammasome activation in BV2 cells expressing WT LRRK2, which was elevated further in G2019S-expressing cells, while pharmacological inhibition of LRRK2 mitigated these effects in both genotypes. Moreover, the media from Mn-treated G2019S-expressing BV2 microglia caused greater toxicity to the cath.a-differentiated (CAD) neuronal cells compared to media from microglia expressing WT. Mn-LRRK2 activated RAB10 which was exacerbated in G2019S. RAB10 played a critical role in LRRK2-mediated Mn toxicity by dysregulating the autophagy-lysosome pathway and NLRP3 inflammasome in microglia. Our novel findings suggest that microglial LRRK2 via RAB10 plays a critical role in Mn-induced neuroinflammation.


Assuntos
Intoxicação por Manganês , Manganês , Camundongos , Humanos , Animais , Manganês/metabolismo , Microglia/metabolismo , Inflamassomos/genética , Inflamassomos/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Serina-Treonina Proteína Quinase-2 com Repetições Ricas em Leucina/genética , Serina-Treonina Proteína Quinase-2 com Repetições Ricas em Leucina/metabolismo , Intoxicação por Manganês/metabolismo , Mutação , Autofagia
3.
N Engl J Med ; 385(25): 2336-2347, 2021 12 16.
Artigo em Inglês | MEDLINE | ID: mdl-34914339

RESUMO

BACKGROUND: The recurrence score based on the 21-gene breast-cancer assay has been clinically useful in predicting a chemotherapy benefit in hormone-receptor-positive, human epidermal growth factor receptor 2 (HER2)-negative, axillary lymph-node-negative breast cancer. In women with positive lymph-node disease, the role of the recurrence score with respect to predicting a benefit of adjuvant chemotherapy is unclear. METHODS: In a prospective trial, we randomly assigned women with hormone-receptor-positive, HER2-negative breast cancer, one to three positive axillary lymph nodes, and a recurrence score of 25 or lower (scores range from 0 to 100, with higher scores indicating a worse prognosis) to endocrine therapy only or to chemotherapy plus endocrine (chemoendocrine) therapy. The primary objective was to determine the effect of chemotherapy on invasive disease-free survival and whether the effect was influenced by the recurrence score. Secondary end points included distant relapse-free survival. RESULTS: A total of 5083 women (33.2% premenopausal and 66.8% postmenopausal) underwent randomization, and 5018 participated in the trial. At the prespecified third interim analysis, the chemotherapy benefit with respect to increasing invasive disease-free survival differed according to menopausal status (P = 0.008 for the comparison of chemotherapy benefit in premenopausal and postmenopausal participants), and separate prespecified analyses were conducted. Among postmenopausal women, invasive disease-free survival at 5 years was 91.9% in the endocrine-only group and 91.3% in the chemoendocrine group, with no chemotherapy benefit (hazard ratio for invasive disease recurrence, new primary cancer [breast cancer or another type], or death, 1.02; 95% confidence interval [CI], 0.82 to 1.26; P = 0.89). Among premenopausal women, invasive disease-free survival at 5 years was 89.0% with endocrine-only therapy and 93.9% with chemoendocrine therapy (hazard ratio, 0.60; 95% CI, 0.43 to 0.83; P = 0.002), with a similar increase in distant relapse-free survival (hazard ratio, 0.58; 95% CI, 0.39 to 0.87; P = 0.009). The relative chemotherapy benefit did not increase as the recurrence score increased. CONCLUSIONS: Among premenopausal women with one to three positive lymph nodes and a recurrence score of 25 or lower, those who received chemoendocrine therapy had longer invasive disease-free survival and distant relapse-free survival than those who received endocrine-only therapy, whereas postmenopausal women with similar characteristics did not benefit from adjuvant chemotherapy. (Funded by the National Cancer Institute and others; RxPONDER ClinicalTrials.gov number, NCT01272037.).


Assuntos
Antineoplásicos Hormonais/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/genética , Metástase Linfática , Adulto , Idoso , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/cirurgia , Quimioterapia Adjuvante , Intervalo Livre de Doença , Feminino , Perfilação da Expressão Gênica , Humanos , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/genética , Pós-Menopausa , Pré-Menopausa , Estudos Prospectivos , Receptor ErbB-2 , Receptores de Esteroides , Reação em Cadeia da Polimerase Via Transcriptase Reversa
4.
Neurochem Res ; 2024 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-39060769

RESUMO

Aluminum (Al) is known to induce neurotoxic effects, potentially contributing to Alzheimer's disease (AD) pathogenesis. Recent studies suggest that epigenetic modification may contribute to Al neurotoxicity, although the mechanisms are still debatable. Therefore, the objective of the present study was to summarize existing data on the involvement of epigenetic mechanisms in Al-induced neurotoxicity, especially AD-type pathology. Existing data demonstrate that Al exposure induces disruption in DNA methylation, histone modifications, and non-coding RNA expression in brains. Alterations in DNA methylation following Al exposure were shown to be mediated by changes in expression and activity of DNA methyltransferases (DNMTs) and ten-eleven translocation proteins (TETs). Al exposure was shown to reduce histone acetylation by up-regulating expression of histone deacetylases (HDACs) and impair histone methylation, ultimately contributing to down-regulation of brain-derived neurotrophic factor (BDNF) expression and activation of nuclear factor κB (NF-κB) signaling. Neurotoxic effects of Al exposure were also associated with aberrant expression of non-coding RNAs, especially microRNAs (miR). Al-induced patterns of miR expression were involved in development of AD-type pathology by increasing amyloid ß (Aß) production through up-regulation of Aß precursor protein (APP) and ß secretase (BACE1) expression (down-regulation of miR-29a/b, miR-101, miR-124, and Let-7c expression), increasing in neuroinflammation through NF-κB signaling (up-regulation of miR-9, miR-125b, miR-128, and 146a), as well as modulating other signaling pathways. Furthermore, reduced global DNA methylation, altered histone modification, and aberrant miRNA expression were associated with cognitive decline in Al-exposed subjects. However, further studies are required to evaluate the contribution of epigenetic mechanisms to Al-induced neurotoxicity and/or AD development.

5.
Glia ; 71(2): 450-466, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36300569

RESUMO

The transcription factor Yin Yang 1 (YY1) is ubiquitously expressed in mammalian cells, regulating the expression of a variety of genes involved in proliferation, differentiation, and apoptosis in a context-dependent manner. While it is well-established that global YY1 knockout (KO) leads to embryonic death in mice and that YY1 deletion in neurons or oligodendrocytes induces impaired brain function, the role of astrocytic YY1 in the brain remains unknown. We investigated the role of astrocytic YY1 in the brain using a glial fibrillary acidic protein (GFAP)-specific YY1 conditional KO (YY1 cKO) mouse model to delete astrocytic YY1. Astrocytic YY1 cKO mice were tested for behavioral phenotypes, such as locomotor activity, coordination, and cognition, followed by an assessment of relevant biological pathways using RNA-sequencing analysis, immunoblotting, and immunohistochemistry in the cortex, midbrain, and cerebellum. YY1 cKO mice showed abnormal phenotypes, movement deficits, and cognitive dysfunction. At the molecular level, astrocytic YY1 deletion altered the expression of genes associated with proliferation and differentiation, p53/caspase apoptotic pathways, oxidative stress response, and inflammatory signaling including NF-κB, STAT, and IRF in all regions. Astrocytic YY1 deletion significantly increased the expression of GFAP as astrocytic activation and Iba1 as microglial activation, indicating astrocytic YY1 deletion activated microglia as well. Accordingly, multiple inflammatory cytokines and chemokines including TNF-α and CXCL10 were elevated. Combined, these novel findings suggest that astrocytic YY1 is a critical transcription factor for normal brain development and locomotor activity, motor coordination, and cognition. Astrocytic YY1 is also essential in preventing pathological oxidative stress, apoptosis, and inflammation.


Assuntos
Fator de Transcrição YY1 , Yin-Yang , Camundongos , Animais , Fator de Transcrição YY1/genética , Fator de Transcrição YY1/metabolismo , Apoptose , Inflamação , Estresse Oxidativo , Encéfalo/metabolismo , Mamíferos/metabolismo
6.
Arch Virol ; 168(4): 117, 2023 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-36947325

RESUMO

The currently named gerbera virus A (GeVA) has been shown to be a novel capillovirus with a complete genome of 6929 nucleotides (nt) (GenBank accession no. OM525829.1). GeVA was detected in Gerbera jamesonii using high-throughput RNA sequencing analysis. The GeVA genome is a single linear RNA with two open reading frames (ORF), similar to those of other capilloviruses. The larger ORF encodes a polyprotein containing four domains, while the smaller ORF encodes a movement protein. The complete genome had 41.0-54.9% nt sequence identity to other those of capilloviruses, while the polyprotein and the movement protein had 26.5-36.4% and 13.1-32.2% amino acid (aa) sequence identity, respectively. Two UUAGGU promoters for subgenomic RNA (sgRNA) transcription were also identified in this study. BLAST analysis demonstrated that the GeVA genome shared the highest sequence similarity with rubber tree capillovirus 1 (MN047299.1) (complete nucleotide sequence identity, 68.54%; polyprotein amino acid sequence identity, 44.53%). Phylogenetic analysis based on complete genome and replication protein sequences placed GeVA alongside other members of the genus Capillovirus in the family Betaflexiviridae. These data suggest that GeVA is a new member of the genus Capillovirus.


Assuntos
Flexiviridae , Sequência de Aminoácidos , Flexiviridae/genética , Genoma Viral , Fases de Leitura Aberta , Filogenia , RNA Viral/genética , RNA Subgenômico
7.
Nano Lett ; 22(4): 1518-1524, 2022 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-35119873

RESUMO

Crystalline films offer various physical properties based on the modulation of their thicknesses and atomic structures. The layer-by-layer assembly of atomically thin crystals provides a powerful means to arbitrarily design films at the atomic level, which are unattainable with existing growth technologies. However, atomically clean assembly of the materials with high scalability and reproducibility remains challenging. We report programmed crystal assembly of graphene and monolayer hexagonal boron nitride, assisted by van der Waals interactions, to form wafer-scale films of pristine interfaces with near-unity yield. The atomic configurations of the films are tailored with layer-resolved compositions and in-plane crystalline orientations. We demonstrate batch-fabricated tunnel device arrays with modulation of the resistance over orders of magnitude by thickness control of the hexagonal boron nitride barrier with single-atom precision and large-scale, twisted multilayer graphene with programmable electronic band structures and crystal symmetries. Our results constitute an important development in the artificial design of large-scale films.

8.
J Biol Chem ; 297(6): 101372, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34756885

RESUMO

Chronic exposure to high levels of manganese (Mn) leads to manganism, a neurological disorder with similar symptoms to those inherent to Parkinson's disease. However, the underlying mechanisms of this pathological condition have yet to be established. Since the human excitatory amino acid transporter 2 (EAAT2) (glutamate transporter 1 in rodents) is predominantly expressed in astrocytes and its dysregulation is involved in Mn-induced excitotoxic neuronal injury, characterization of the mechanisms that mediate the Mn-induced impairment in EAAT2 function is crucial for the development of novel therapeutics against Mn neurotoxicity. Repressor element 1-silencing transcription factor (REST) exerts protective effects in many neurodegenerative diseases. But the effects of REST on EAAT2 expression and ensuing neuroprotection are unknown. Given that the EAAT2 promoter contains REST binding sites, the present study investigated the role of REST in EAAT2 expression at the transcriptional level in astrocytes and Mn-induced neurotoxicity in an astrocyte-neuron coculture system. The results reveal that astrocytic REST positively regulates EAAT2 expression with the recruitment of an epigenetic modifier, cAMP response element-binding protein-binding protein/p300, to its consensus binding sites in the EAAT2 promoter. Moreover, astrocytic overexpression of REST attenuates Mn-induced reduction in EAAT2 expression, leading to attenuation of glutamate-induced neurotoxicity in the astrocyte-neuron coculture system. Our findings demonstrate that astrocytic REST plays a critical role in protection against Mn-induced neurotoxicity by attenuating Mn-induced EAAT2 repression and the ensuing excitotoxic dopaminergic neuronal injury. This indicates that astrocytic REST could be a potential molecular target for the treatment of Mn toxicity and other neurological disorders associated with EAAT2 dysregulation.


Assuntos
Neurônios Dopaminérgicos/metabolismo , Transportador 2 de Aminoácido Excitatório/metabolismo , Manganês/farmacologia , Proteínas Repressoras/fisiologia , Regulação para Cima/fisiologia , Animais , Astrócitos/metabolismo , Linhagem Celular , Neurônios Dopaminérgicos/efeitos dos fármacos , Transportador 2 de Aminoácido Excitatório/genética , Ácido Glutâmico/metabolismo , Humanos , Camundongos , Regiões Promotoras Genéticas , Sequências Reguladoras de Ácido Nucleico , Transcrição Gênica/fisiologia
9.
Glia ; 70(10): 1886-1901, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35638297

RESUMO

Chronic manganese (Mn) overexposure causes a neurological disorder, referred to as manganism, exhibiting symptoms similar to parkinsonism. Dysfunction of the repressor element-1 silencing transcription factor (REST) is associated with various neurodegenerative diseases such as Parkinson's disease, Alzheimer's disease, and Mn-induced neurotoxicity, but its cellular and molecular mechanisms have yet to be fully characterized. Although neuronal REST is known to be neuroprotective, the role of astrocytic REST in neuroprotection remains to be established. We investigated if astrocytic REST in the striatal region of the mouse brain where Mn preferentially accumulates plays a role in Mn-induced neurotoxicity. Striatal astrocytic REST was deleted by infusion of adeno-associated viral vectors containing sequences of the glial fibrillary acidic protein promoter-driven Cre recombinase into the striatum of RESTflox/flox mice for 3 weeks, followed by Mn exposure (30 mg/kg, daily, intranasally) for another 3 weeks. Striatal astrocytic REST deletion exacerbated Mn-induced impairment of locomotor activity and cognitive function with further decrease in Mn-reduced protein levels of tyrosine hydroxylase and glutamate transporter 1 (GLT-1) in the striatum. Astrocytic REST deletion also exacerbated the Mn-induced proinflammatory mediator COX-2, as well as cytokines such as TNF-α, IL-1ß, and IL-6, in the striatum. Mn-induced detrimental astrocytic products such as proinflammatory cytokines on neuronal toxicity were attenuated by astrocytic REST overexpression, but exacerbated by REST inhibition in an in vitro model using primary human astrocytes and Lund human mesencephalic (LUHMES) neuronal culture. These findings indicate that astrocytic REST plays a critical role against Mn-induced neurotoxicity by modulating astrocytic proinflammatory factors and GLT-1.


Assuntos
Astrócitos , Intoxicação por Manganês , Proteínas Repressoras , Animais , Astrócitos/metabolismo , Deleção de Genes , Humanos , Manganês/toxicidade , Intoxicação por Manganês/genética , Camundongos , Proteínas Repressoras/genética
10.
BMC Geriatr ; 22(1): 367, 2022 04 27.
Artigo em Inglês | MEDLINE | ID: mdl-35477358

RESUMO

BACKGROUND: The recently developed Screening Tool of Older Persons' Prescriptions in Frail adults with a limited life expectancy (STOPPFrail) criteria can be helpful for screening medications (PIMs), but it is yet to be widely used in clinical practice. Herein, we aimed to investigate the prevalence of PIMs based on the STOPPFrail criteria (STOPPFrail-PIM) among frail older adults with limited life expectancy admitted to the geriatric center. METHODS: This was a retrospective cross-sectional study conducted in the geriatric center at an academic tertiary care hospital in Korea. We evaluated frail older adults with limited life expectancy who received comprehensive geriatric assessment (CGA) admitted between 1 January, 2019 and 30 June, 2020. Frail older adults with limited life expectancy were identified by geriatricians with retrospective records and the prevalence of STOPPFrail-PIMs was analysed by trained pharmacists. Descriptive analysis, t-test, and chi-square test were conducted using IBM SPSS software version 25.0. RESULTS: Among 504 older adults who underwent CGA after admission, 171 frail older adults with limited life expectancy were identified by geriatricians and included in the study. An average of 11.3 ± 4.7 medications were administered regularly to each patient before admission. Overall, 97.1% (166/171) had at least one STOPPFrail-PIM, and the mean number of STOPPFrail-PIM was 4.2 ± 2.8. Drugs without clear clinical indication (A2) were the most frequent pre-admission STOPPFrail-PIM, followed by lipid-lowering therapies (B1) and neuroleptic antipsychotics (D1). The number of STOPPFrail-PIM was significantly lower at discharge than that at admission, with the decrease being the highest for A2 at 94.7%. CONCLUSIONS: Most frail older adults with limited life expectancy had at least one STOPPFrail-PIM at admission, and the rate of STOPPFrail-PIM decreased significantly at discharge after the geriatric multidisciplinary team care. Further studies are needed to investigate the association between the use of STOPPFrail-PIM and adverse consequences in frail older adults.


Assuntos
Idoso Fragilizado , Lista de Medicamentos Potencialmente Inapropriados , Idoso , Idoso de 80 Anos ou mais , Estudos Transversais , Humanos , Prescrição Inadequada/prevenção & controle , Expectativa de Vida , Prevalência , Estudos Retrospectivos
11.
Neurocrit Care ; 36(3): 888-896, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-34791593

RESUMO

BACKGROUND: Intravenous propacetamol is commonly used to control fever and pain in neurocritically ill patients in whom oral administration is often difficult. However, several studies reported that intravenous propacetamol may cause blood pressure drop. Thus, we aimed to investigate the occurrence and risk factors for intravenous propacetamol-induced blood pressure drop in neurocritically ill patients. METHODS: This retrospective study included consecutive patients who were administered intravenous propacetamol in a neurointensive care unit at a single tertiary academic hospital between April 2013 and June 2020. The exact timing of intravenous propacetamol administration was collected from a database of the electronic barcode medication administration system. Blood pressure drop was defined as a systolic blood pressure below 90 mm Hg or a decrease by 30 mm Hg or more. Blood pressure, pulse rate, and body temperature were collected at baseline and within 2 h after intravenous propacetamol administration. The incidence of blood pressure drop was evaluated, and multivariable logistic regression analysis was performed to identify risk factors for blood pressure drop events. RESULTS: A total of 16,586 instances of intravenous propacetamol administration in 4916 patients were eligible for this study. Intravenous propacetamol resulted in a significant decrease in systolic blood pressure (baseline 131.1 ± 17.8 mm Hg; within 1 h 124.6 ± 17.3 mm Hg; between 1 and 2 h 123.4 ± 17.4 mm Hg; P < 0.01). The incidence of blood pressure drop events was 13.5% within 2 h after intravenous propacetamol. Older age, lower or higher baseline systolic blood pressure, fever, higher Acute Physiology and Chronic Health Evaluation II score, and concomitant administration of vasopressors/inotropes or analgesics/sedatives were significant factors associated with the occurrence of blood pressure drop events after intravenous propacetamol administration. CONCLUSIONS: Intravenous propacetamol can induce hemodynamic changes and blood pressure drop events in neurocritically ill patients. This study identified the risk factors for blood pressure drop events. On the basis of our results, judicious use of intravenous propacetamol is warranted for neurocritically ill patients with risk factors that make them more susceptible to hemodynamic changes.


Assuntos
Acetaminofen , Hipotensão , Acetaminofen/análogos & derivados , Acetaminofen/uso terapêutico , Pressão Sanguínea , Febre/induzido quimicamente , Febre/epidemiologia , Humanos , Hipotensão/tratamento farmacológico , Estudos Retrospectivos , Fatores de Risco
12.
J Biol Chem ; 295(10): 3040-3054, 2020 03 06.
Artigo em Inglês | MEDLINE | ID: mdl-32001620

RESUMO

Dopaminergic functions are important for various biological activities, and their impairment leads to neurodegeneration, a hallmark of Parkinson's disease (PD). Chronic manganese (Mn) exposure causes the neurological disorder manganism, presenting symptoms similar to those of PD. Emerging evidence has linked the transcription factor RE1-silencing transcription factor (REST) to PD and also Alzheimer's disease. But REST's role in dopaminergic neurons is unclear. Here, we investigated whether REST protects dopaminergic neurons against Mn-induced toxicity and enhances expression of the dopamine-synthesizing enzyme tyrosine hydroxylase (TH). We report that REST binds to RE1 consensus sites in the TH gene promoter, stimulates TH transcription, and increases TH mRNA and protein levels in dopaminergic cells. REST binding to the TH promoter recruited the epigenetic modifier cAMP-response element-binding protein-binding protein/p300 and thereby up-regulated TH expression. REST relieved Mn-induced repression of TH promoter activity, mRNA, and protein levels and also reduced Mn-induced oxidative stress, inflammation, and apoptosis in dopaminergic neurons. REST reduced Mn-induced proinflammatory cytokines, including tumor necrosis factor α, interleukin 1ß (IL-1ß), IL-6, and interferon γ. Moreover, REST inhibited the Mn-induced proapoptotic proteins Bcl-2-associated X protein (Bax) and death-associated protein 6 (Daxx) and attenuated an Mn-induced decrease in the antiapoptotic proteins Bcl-2 and Bcl-xL. REST also enhanced the expression of antioxidant proteins, including catalase, NF-E2-related factor 2 (Nrf2), and heme oxygenase 1 (HO-1). Our findings indicate that REST activates TH expression and thereby protects neurons against Mn-induced toxicity and neurological disorders associated with dopaminergic neurodegeneration.


Assuntos
Manganês/toxicidade , Proteínas Repressoras/metabolismo , Tirosina 3-Mono-Oxigenase/metabolismo , Regulação para Cima/efeitos dos fármacos , Animais , Apoptose/efeitos dos fármacos , Sequência de Bases , Proteína de Ligação a CREB/metabolismo , Neurônios Dopaminérgicos/citologia , Neurônios Dopaminérgicos/efeitos dos fármacos , Neurônios Dopaminérgicos/metabolismo , Heme Oxigenase-1/metabolismo , Interleucina-1beta/metabolismo , Camundongos , Fator 2 Relacionado a NF-E2/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Regiões Promotoras Genéticas , Ligação Proteica , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Proteínas Repressoras/genética , Ativação Transcricional , Fator de Necrose Tumoral alfa/metabolismo , Tirosina 3-Mono-Oxigenase/química , Tirosina 3-Mono-Oxigenase/genética
13.
J Biol Chem ; 295(46): 15662-15676, 2020 11 13.
Artigo em Inglês | MEDLINE | ID: mdl-32893191

RESUMO

Manganese (Mn)-induced neurotoxicity resembles Parkinson's disease (PD), but the mechanisms underpinning its effects remain unknown. Mn dysregulates astrocytic glutamate transporters, GLT-1 and GLAST, and dopaminergic function, including tyrosine hydroxylase (TH). Our previous in vitro studies have shown that Mn repressed GLAST and GLT-1 via activation of transcription factor Yin Yang 1 (YY1). Here, we investigated if in vivo astrocytic YY1 deletion mitigates Mn-induced dopaminergic neurotoxicity, attenuating Mn-induced reduction in GLAST/GLT-1 expression in murine substantia nigra (SN). AAV5-GFAP-Cre-GFP particles were infused into the SN of 8-week-old YY1 flox/flox mice to generate a region-specific astrocytic YY1 conditional knockout (cKO) mouse model. 3 weeks after adeno-associated viral (AAV) infusion, mice were exposed to 330 µg of Mn (MnCl2 30 mg/kg, intranasal instillation, daily) for 3 weeks. After Mn exposure, motor functions were determined in open-field and rotarod tests, followed by Western blotting, quantitative PCR, and immunohistochemistry to assess YY1, TH, GLAST, and GLT-1 levels. Infusion of AAV5-GFAP-Cre-GFP vectors into the SN resulted in region-specific astrocytic YY1 deletion and attenuation of Mn-induced impairment of motor functions, reduction of TH-expressing cells in SN, and TH mRNA/protein levels in midbrain/striatum. Astrocytic YY1 deletion also attenuated the Mn-induced decrease in GLAST/GLT-1 mRNA/protein levels in midbrain. Moreover, YY1 deletion abrogated its interaction with histone deacetylases in astrocytes. These results indicate that astrocytic YY1 plays a critical role in Mn-induced neurotoxicity in vivo, at least in part, by reducing astrocytic GLAST/GLT-1. Thus, YY1 might be a potential target for treatment of Mn toxicity and other neurological disorders associated with dysregulation of GLAST/GLT-1.


Assuntos
Intoxicação por Manganês/patologia , Substância Negra/metabolismo , Fator de Transcrição YY1/metabolismo , Animais , Astrócitos/citologia , Astrócitos/metabolismo , Cloretos/toxicidade , Regulação para Baixo/efeitos dos fármacos , Transportador 1 de Aminoácido Excitatório/genética , Transportador 1 de Aminoácido Excitatório/metabolismo , Transportador 2 de Aminoácido Excitatório/genética , Transportador 2 de Aminoácido Excitatório/metabolismo , Feminino , Histona Desacetilases/metabolismo , Locomoção/efeitos dos fármacos , Masculino , Compostos de Manganês , Intoxicação por Manganês/metabolismo , Camundongos , Camundongos Knockout , RNA Mensageiro/metabolismo , Tirosina 3-Mono-Oxigenase/genética , Tirosina 3-Mono-Oxigenase/metabolismo , Fator de Transcrição YY1/genética
14.
FASEB J ; 34(12): 16276-16290, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33078455

RESUMO

Clusterin (CLU) is a heterodimeric glycoprotein involved in a range of biological processes. We investigated the function of CLU as a novel regulator of adipogenesis. CLU expression increased during 3T3-L1 preadipocyte differentiation. CLU overexpression promoted adipogenic differentiation of preadipocytes and increased the mRNA levels of adipogenic markers including peroxisome proliferator-activated receptor γ (Pparg) and CCAAT enhancer-binding protein α (Cebpa). Conversely, knockdown of CLU attenuated adipogenesis and reduced transcript levels of Pparg and Cebpa. However, the promoter activities of both the Pparg and the Cebpa gene were not affected by alteration of CLU expression on its own. Additionally, the protein level of Krüppel-like factor 5 (KLF5), an upstream transcription factor of Pparg and Cebpa involved in adipogenic differentiation, was upregulated by CLU overexpression, although the mRNA level of Klf5 was not altered by changes in the expression level of CLU. Cycloheximide chase assay showed that the increased level of KLF5 by CLU overexpression was due to decreased degradation of KLF5 protein. Interestingly, CLU increased the stability of KLF5 by decreasing KLF5 ubiquitination. CLU inhibited the interaction between KLF5 and F-box/WD repeat-containing protein 7, which is an E3 ubiquitin ligase that targets KLF5. The adipogenic role of CLU was also addressed in mesenchymal stem cells (MSCs) and Clu-/- mouse embryonic fibroblasts (MEFs). Furthermore, CLU enhanced KLF5-mediated transcriptional activation of both the Cebpa and the Pparg promoter. Taken together, these results suggest that CLU is a novel regulator of adipocyte differentiation by modulating the protein stability of the adipogenic transcription factor KLF5.


Assuntos
Adipócitos/fisiologia , Diferenciação Celular/genética , Clusterina/genética , Fatores de Transcrição Kruppel-Like/genética , Células 3T3-L1 , Adipogenia/genética , Animais , Linhagem Celular , Fibroblastos/fisiologia , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Regiões Promotoras Genéticas/genética , Ativação Transcricional/genética , Ubiquitina-Proteína Ligases/genética , Ubiquitinação/genética
15.
Support Care Cancer ; 29(6): 3025-3034, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33037903

RESUMO

PURPOSE: We aimed to investigate the prevalence and predicting factors of inappropriate polypharmacy including potentially inappropriate medications (PIMs) and drug-drug interactions (DDIs) and their associations with emergency department (ED) visits in older Korean patients receiving anti-neoplastic therapy. METHODS: We identified older patients receiving anti-neoplastic therapy in 2016 from the National Health Claims database. We investigated the prevalence of inappropriate polypharmacy comprising PIMs and DDIs in geriatric patients according to the 2019 American Geriatrics Society Beers Criteria® and chemotherapeutic DDIs using Lexicomp OnlineTM and Micromedex®. A nested case-control study was conducted to evaluate the associations between inappropriate polypharmacy and ED visits during anti-neoplastic therapy. Multivariate logistic regressions were performed after adjusting for age, sex, cancer diagnosis, prior ED visits, Charlson Comorbidity Index, and type of anti-neoplastic therapy. RESULTS: Inappropriate polypharmacy, its subtype PIMs, geriatric, and chemotherapeutic DDIs were observed in 85.4%, 80.4%, 17.3%, and 37.9% of the 21,956 patients receiving anti-neoplastic therapy, respectively. After adjusting for confounding factors, the presence of inappropriate polypharmacy (adjusted odds ratio (aOR) 2.15, 95% confidence interval (CI) 1.97-2.35), 2 or more PIMs (aOR 1.85, 95% CI 1.68-2.02), 2 or more chemotherapeutic DDIs (aOR 2.88, 95% CI 2.54-3.28), and geriatric DDIs (aOR 1.61, 95% CI 1.43-1.80) increased the likelihood of ED visits during anti-neoplastic therapy. CONCLUSION: This nationwide study showed that inappropriate polypharmacy was prevalent and increased the risk of ED visits in older patients receiving anti-neoplastic therapy. Study findings suggested a need to implement deprescribing strategies in this population.


Assuntos
Antineoplásicos/uso terapêutico , Planejamento em Saúde Comunitária/métodos , Serviço Hospitalar de Emergência/normas , Prescrição Inadequada/estatística & dados numéricos , Polimedicação , Idoso , Antineoplásicos/farmacologia , Estudos Transversais , Feminino , Humanos , Masculino
16.
Eur J Cancer Care (Engl) ; 30(5): e13447, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33774893

RESUMO

OBJECTIVE: We investigated the contribution of supplement use to total nutrient intake, the prevalence of inadequate nutrient intake and the factors associated with supplement use among breast cancer survivors. METHODS: A total of 701 Korean breast cancer survivors were included. We calculated the contribution of dietary supplements to total nutrient intake and the proportion of the population below the estimated average requirements (EARs) or exceeding the tolerable upper intake levels (ULs). Stepwise logistic regression was used to identify factors associated with dietary supplement use. RESULTS: A total of 66.5% of the survivors used dietary supplements, with multivitamins and minerals being the most commonly consumed ones. The per cent contribution of supplement to the total intake was the highest for vitamin C. 28.2%-55.4% of the non-users consumed below the EAR of riboflavin, folate and calcium; 6.1%, 4.9% and 6.5% of the supplement users consumed above the UL of vitamins A and C, and iron, respectively. Supplement users had higher education levels or longer survival time. CONCLUSION: 66.5% of Korean breast cancer survivors used dietary supplements. A higher education level or prolonged survival time was associated with higher use of dietary supplements.


Assuntos
Neoplasias da Mama , Sobreviventes de Câncer , Estudos Transversais , Dieta , Suplementos Nutricionais , Ingestão de Alimentos , Feminino , Humanos , Sobreviventes
17.
Int J Mol Sci ; 22(9)2021 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-33925013

RESUMO

Understanding of the immediate mechanisms of Mn-induced neurotoxicity is rapidly evolving. We seek to provide a summary of recent findings in the field, with an emphasis to clarify existing gaps and future research directions. We provide, here, a brief review of pertinent discoveries related to Mn-induced neurotoxicity research from the last five years. Significant progress was achieved in understanding the role of Mn transporters, such as SLC39A14, SLC39A8, and SLC30A10, in the regulation of systemic and brain manganese handling. Genetic analysis identified multiple metabolic pathways that could be considered as Mn neurotoxicity targets, including oxidative stress, endoplasmic reticulum stress, apoptosis, neuroinflammation, cell signaling pathways, and interference with neurotransmitter metabolism, to name a few. Recent findings have also demonstrated the impact of Mn exposure on transcriptional regulation of these pathways. There is a significant role of autophagy as a protective mechanism against cytotoxic Mn neurotoxicity, yet also a role for Mn to induce autophagic flux itself and autophagic dysfunction under conditions of decreased Mn bioavailability. This ambivalent role may be at the crossroad of mitochondrial dysfunction, endoplasmic reticulum stress, and apoptosis. Yet very recent evidence suggests Mn can have toxic impacts below the no observed adverse effect of Mn-induced mitochondrial dysfunction. The impact of Mn exposure on supramolecular complexes SNARE and NLRP3 inflammasome greatly contributes to Mn-induced synaptic dysfunction and neuroinflammation, respectively. The aforementioned effects might be at least partially mediated by the impact of Mn on α-synuclein accumulation. In addition to Mn-induced synaptic dysfunction, impaired neurotransmission is shown to be mediated by the effects of Mn on neurotransmitter systems and their complex interplay. Although multiple novel mechanisms have been highlighted, additional studies are required to identify the critical targets of Mn-induced neurotoxicity.


Assuntos
Intoxicação por Manganês/metabolismo , Animais , Proteínas de Transporte de Cátions/metabolismo , Humanos , Manganês/toxicidade , Doenças Neurodegenerativas/induzido quimicamente , Transmissão Sináptica/efeitos dos fármacos
18.
Cancer Sci ; 111(10): 3912-3925, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32761968

RESUMO

The use of multigene panel testing for patients with a predisposition to breast/ovarian cancer is increasing as the identification of variants is useful for diagnosis and disease management. We identified pathogenic and likely pathogenic (P/LP) variants of high-and moderate-risk genes using a 23-gene germline cancer panel in 518 patients with hereditary breast and ovarian cancers (HBOC). The frequency of P/LP variants was 12.4% (64/518) for high- and moderate-penetrant genes, namely, BRCA2 (5.6%), BRCA1 (3.3%), CHEK2 (1.2%), MUTYH (0.8%), PALB2 (0.8%), MLH1 (0.4%), ATM (0.4%), BRIP1 (0.4%), TP53 (0.2%), and PMS2 (0.2%). Five patients possessed two P/LP variants in BRCA1/2 and other genes. We also compared the results from in silico splicing predictive tools and exon splicing patterns from patient samples by analyzing RT-PCR product sequences in six P/LP intronic variants and two intronic variants of unknown significance (VUS). Altered transcriptional fragments were detected for P/LP intronic variants in BRCA1, BRIP1, CHEK2, PARB2, and PMS2. Notably, we identified an in-frame deletion of the BRCA1 C-terminal (BRCT) domain by exon skipping in BRCA1 c.5152+6T>C-as known VUS-indicating a risk for HBOC. Thus, exon splicing analysis can improve the identification of veiled intronic variants that would aid decision making and determination of hereditary cancer risk.


Assuntos
Proteína BRCA1/genética , Neoplasias da Mama/genética , Proteínas de Neoplasias/genética , Neoplasias Ovarianas/genética , Adulto , Neoplasias da Mama/patologia , Quinase do Ponto de Checagem 2/genética , Éxons/genética , Proteínas de Grupos de Complementação da Anemia de Fanconi/genética , Feminino , Mutação em Linhagem Germinativa/genética , Humanos , Pessoa de Meia-Idade , Endonuclease PMS2 de Reparo de Erro de Pareamento/genética , Neoplasias Ovarianas/patologia , RNA Helicases/genética
19.
N Engl J Med ; 376(22): 2147-2159, 2017 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-28564564

RESUMO

BACKGROUND: Patients who have residual invasive carcinoma after the receipt of neoadjuvant chemotherapy for human epidermal growth factor receptor 2 (HER2)-negative breast cancer have poor prognoses. The benefit of adjuvant chemotherapy in these patients remains unclear. METHODS: We randomly assigned 910 patients with HER2-negative residual invasive breast cancer after neoadjuvant chemotherapy (containing anthracycline, taxane, or both) to receive standard postsurgical treatment either with capecitabine or without (control). The primary end point was disease-free survival. Secondary end points included overall survival. RESULTS: The result of the prespecified interim analysis met the primary end point, so this trial was terminated early. The final analysis showed that disease-free survival was longer in the capecitabine group than in the control group (74.1% vs. 67.6% of the patients were alive and free from recurrence or second cancer at 5 years; hazard ratio for recurrence, second cancer, or death, 0.70; 95% confidence interval [CI], 0.53 to 0.92; P=0.01). Overall survival was longer in the capecitabine group than in the control group (89.2% vs. 83.6% of the patients were alive at 5 years; hazard ratio for death, 0.59; 95% CI, 0.39 to 0.90; P=0.01). Among patients with triple-negative disease, the rate of disease-free survival was 69.8% in the capecitabine group versus 56.1% in the control group (hazard ratio for recurrence, second cancer, or death, 0.58; 95% CI, 0.39 to 0.87), and the overall survival rate was 78.8% versus 70.3% (hazard ratio for death, 0.52; 95% CI, 0.30 to 0.90). The hand-foot syndrome, the most common adverse reaction to capecitabine, occurred in 73.4% of the patients in the capecitabine group. CONCLUSIONS: After standard neoadjuvant chemotherapy containing anthracycline, taxane, or both, the addition of adjuvant capecitabine therapy was safe and effective in prolonging disease-free survival and overall survival among patients with HER2-negative breast cancer who had residual invasive disease on pathological testing. (Funded by the Advanced Clinical Research Organization and the Japan Breast Cancer Research Group; CREATE-X UMIN Clinical Trials Registry number, UMIN000000843 .).


Assuntos
Antimetabólitos Antineoplásicos/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Capecitabina/uso terapêutico , Adulto , Idoso , Antimetabólitos Antineoplásicos/efeitos adversos , Neoplasias da Mama/mortalidade , Neoplasias da Mama/cirurgia , Capecitabina/efeitos adversos , Quimioterapia Adjuvante/efeitos adversos , Feminino , Síndrome Mão-Pé/etiologia , Humanos , Pessoa de Meia-Idade , Terapia Neoadjuvante , Estadiamento de Neoplasias , Cuidados Pré-Operatórios , Receptor ErbB-2 , Análise de Sobrevida , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Neoplasias de Mama Triplo Negativas/mortalidade
20.
Eur J Clin Microbiol Infect Dis ; 39(1): 75-83, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31482420

RESUMO

This study aimed to evaluate the impact of the intervention targeting the redundant combination of antianaerobic antimicrobials on its incidence and associated antimicrobial consumption. To reveal the characteristics of the combination and the change in the related workload over time was an additional aim of the study. The combinations of metronidazole or clindamycin with antianaerobic antimicrobials were classified into redundant or acceptable, according to the target indications. A pharmacist-based prospective audit and feedback targeting the redundant antianaerobic combination was conducted. Segmented regression analysis was performed to evaluate the impact of the intervention. As a quantitative index of the interventional activity, the change in the number of signed consultation notes was evaluated. After the initiation of the intervention, the median monthly cumulative incidence of the redundant combination decreased from 5.29 (Interquartile range [IQR] 4.94-5.70) to 3.33 (IQR 2.87-3.71) (p < 0.001) per 1000 admissions per month. The consumption of concurrently administered metronidazole and clindamycin decreased from 3.34 (IQR 2.97-4.10) to 1.74 (IQR 1.19-1.93) (p < 0.001) per 1000 patient-days per month. Segmented regression analysis revealed that the monthly cumulative incidence decreased by 28.5% after the initiation of the intervention (change in level - 1.640, p = 0.019) and the monthly consumption decreased by 33.9% (change in level - 1.409, p = 0.009). The number of consultation notes per 1000 admissions per month decreased over time (regression coefficient - 0.004, p < 0.001). The pharmacist-based intervention significantly reduced the incidence and associated antimicrobial consumption of the redundant antianaerobic combination. The overall related workload reduced steadily over time.


Assuntos
Antibacterianos/administração & dosagem , Farmacêuticos , Prescrições/normas , Qualidade da Assistência à Saúde , Bactérias Anaeróbias/efeitos dos fármacos , Clindamicina/administração & dosagem , Humanos , Prescrição Inadequada , Metronidazol/administração & dosagem , Médicos , Estudos Prospectivos
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