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1.
Nat Commun ; 11(1): 4958, 2020 10 02.
Artigo em Inglês | MEDLINE | ID: mdl-33009395

RESUMO

Striatal dopamine (DA) is critical for action and learning. Recent data show that DA release is under tonic inhibition by striatal GABA. Ambient striatal GABA tone on striatal projection neurons can be determined by plasma membrane GABA uptake transporters (GATs) located on astrocytes and neurons. However, whether striatal GATs and astrocytes determine DA output are unknown. We reveal that DA release in mouse dorsolateral striatum, but not nucleus accumbens core, is governed by GAT-1 and GAT-3. These GATs are partly localized to astrocytes, and are enriched in dorsolateral striatum compared to accumbens core. In a mouse model of early parkinsonism, GATs are downregulated, tonic GABAergic inhibition of DA release augmented, and nigrostriatal GABA co-release attenuated. These data define previously unappreciated and important roles for GATs and astrocytes in supporting DA release in striatum, and reveal a maladaptive plasticity in early parkinsonism that impairs DA output in vulnerable striatal regions.


Assuntos
Corpo Estriado/metabolismo , Dopamina/metabolismo , Regulação para Baixo , Proteínas da Membrana Plasmática de Transporte de GABA/metabolismo , Transtornos Parkinsonianos/metabolismo , Ácido gama-Aminobutírico/metabolismo , Animais , Astrócitos/metabolismo , Membrana Celular/metabolismo , Modelos Animais de Doenças , Glutamato Descarboxilase/metabolismo , Camundongos Endogâmicos C57BL , Modelos Biológicos , Núcleo Accumbens/metabolismo
2.
Zhonghua Zhong Liu Za Zhi ; 42(8): 629-634, 2020 Aug 23.
Artigo em Chinês | MEDLINE | ID: mdl-32867453

RESUMO

Objective: To investigate the effect of esculin on the proliferation of triple negative breast cancer cells and its molecular mechanism. Methods: MDA-MB-231 cells were treated with 28, 56, 112, 225, 450 and 900 µmol/L of esculin for 24, 48 and 72 h, respectively, and the cell viability was detected by cell counting kit 8 (CCK-8) assay. In addition, MDA-MB-231 cells were treated with 0, 225, 450 and 900 µmol/L of esculin for 48 h. And then the changes in cell morphology were observed by inverted microscope. The clone-forming ability was detected by colony formation assay. The mRNA expression levels of FBI-1, p53 and p21 were detected using real-time fluorescence quantitative polymerase chain reaction. The protein expression levels of FBI-1, p53, p21 and Ki67 were detected by western blot. Results: Compared with the blank control group, the cell viability of MDA-MB-231 cells that treated with esculin significantly decreased in a dose-dependent and time-dependent manners. After treatment with esculin, MDA-MB-231 cells shrunk, flattened, adhered poorly to the culture dish and the cell spacing became larger. Meanwhile, shedding and incomplete cells appeared, of which 900 µmol/L of esculin treatment group showed the most dramatic changes. In addition, the colony formation ratios were decreased to (77.18±5.13)%, (65.94±4.98)% and (45.92±3.70)% in the 225, 450 and 900 µmol/L of esculin treatment groups compared with blank control, respectively (P<0.01). Furthermore, the mRNA and protein expressions of FBI-1 increased, while the levels of p53 and p21 mRNA and protein, as well as the protein expression of Ki67 decreased in a concentration-dependent manner (P<0.01). Conclusion: Esculin may regulate cell cycle-related p53-p21 pathway via FBI-1 mediated DNA replication, thus inhibit the proliferation of triple negative breast cancer cells.


Assuntos
Neoplasias da Mama/patologia , Proliferação de Células/efeitos dos fármacos , Esculina/farmacologia , RNA Mensageiro/genética , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Neoplasias de Mama Triplo Negativas/genética , Neoplasias da Mama/metabolismo , Ciclo Celular , Linhagem Celular Tumoral , Proteínas de Ligação a DNA , Regulação para Baixo/efeitos dos fármacos , Feminino , Humanos , Fatores de Transcrição , Neoplasias de Mama Triplo Negativas/patologia
3.
PLoS Pathog ; 16(8): e1008131, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32866196

RESUMO

Invasion of hepatocytes by Plasmodium sporozoites initiates the pre-erythrocytic step of a malaria infection. Subsequent development of the parasite within hepatocytes and exit from them is essential for starting the disease-causing erythrocytic cycle. Identification of signaling pathways that operate in pre-erythrocytic stages provides insight into a critical step of infection and potential targets for chemoprotection from malaria. We demonstrate that P. berghei homologs of Calcium Dependent Protein Kinase 1 (CDPK1), CDPK4 and CDPK5 play overlapping but distinct roles in sporozoite invasion and parasite egress from hepatocytes. All three kinases are expressed in sporozoites. All three are required for optimal motility of sporozoites and consequently their invasion of hepatocytes. Increased cGMP can compensate for the functional loss of CDPK1 and CDPK5 during sporozoite invasion but cannot overcome loss of CDPK4. CDPK1 and CDPK5 expression is downregulated after sporozoite invasion. CDPK5 reappears in a subset of late stage liver stages and is present in all merosomes. Chemical inhibition of CDPK4 and depletion of CDPK5 in liver stages implicate these kinases in the formation and/or release of merosomes from mature liver stages. Furthermore, depletion of CDPK5 in merosomes significantly delays initiation of the erythrocytic cycle without affecting infectivity of hepatic merozoites. These data suggest that CDPK5 may be required for the rupture of merosomes. Our work provides evidence that sporozoite invasion requires CDPK1 and CDPK5, and suggests that CDPK5 participates in the release of hepatic merozoites.


Assuntos
Regulação para Baixo , Regulação Enzimológica da Expressão Gênica , Malária/epidemiologia , Merozoítos/enzimologia , Plasmodium berghei/enzimologia , Proteínas Quinases/biossíntese , Proteínas de Protozoários/biossíntese , Esporozoítos/enzimologia , Animais , Eritrócitos/enzimologia , Eritrócitos/parasitologia , Feminino , Células Hep G2 , Humanos , Fígado/enzimologia , Fígado/parasitologia , Malária/patologia , Camundongos
4.
Nat Commun ; 11(1): 4664, 2020 09 16.
Artigo em Inglês | MEDLINE | ID: mdl-32938919

RESUMO

Cardiorenal syndrome type 4 (CRS4) is a common complication of chronic kidney disease (CKD), but the pathogenic mechanisms remain elusive. Here we report that morphological and functional changes in myocardial mitochondria are observed in CKD mice, especially decreases in oxidative phosphorylation and fatty acid metabolism. High phosphate (HP), a hallmark of CKD, contributes to myocardial energy metabolism dysfunction by downregulating peroxisome proliferator-activated receptor gamma coactivator 1 alpha (PGC1α). Furthermore, the transcriptional factor interferon regulatory factor 1 (IRF1) is revealed as the key molecule upregulated by HP through histone H3K9 acetylation, and responsible for the HP-mediated transcriptional inhibition of PGC1α by directly binding to its promoter region. Conversely, restoration of PGC1α expression or genetic knockdown of IRF1 significantly attenuates HP-induced alterations in vitro and in vivo. These findings demonstrate that IRF1-PGC1α axis-mediated myocardial energy metabolism remodeling plays a crucial role in the pathogenesis of CRS4.


Assuntos
Síndrome Cardiorrenal/metabolismo , Fator Regulador 1 de Interferon/metabolismo , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismo , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Síndrome Cardiorrenal/patologia , Modelos Animais de Doenças , Regulação para Baixo , Metabolismo Energético , Técnicas de Silenciamento de Genes , Taxa de Filtração Glomerular , Glucuronidase/genética , Insuficiência Cardíaca/etiologia , Insuficiência Cardíaca/metabolismo , Humanos , Fator Regulador 1 de Interferon/genética , Masculino , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Knockout , Pessoa de Meia-Idade , Mitocôndrias Cardíacas/metabolismo , Mitocôndrias Cardíacas/patologia , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/genética , Fosfatos/metabolismo , Regiões Promotoras Genéticas , Ratos , Insuficiência Renal Crônica/complicações , Insuficiência Renal Crônica/metabolismo , Adulto Jovem
5.
Anesth Analg ; 131(4): 993-999, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32925314

RESUMO

BACKGROUND: The cellular immune system is of pivotal importance with regard to the response to severe infections. Monocytes/macrophages are considered key immune cells in infections and downregulation of the surface expression of monocytic human leukocyte antigen-DR (mHLA-DR) within the major histocompatibility complex class II reflects a state of immunosuppression, also referred to as injury-associated immunosuppression. As the role of immunosuppression in coronavirus disease 2019 (COVID-19) is currently unclear, we seek to explore the level of mHLA-DR expression in COVID-19 patients. METHODS: In a preliminary prospective monocentric observational study, 16 COVID-19-positive patients (75% male, median age: 68 [interquartile range 59-75]) requiring hospitalization were included. The median Acute Physiology and Chronic Health Evaluation-II (APACHE-II) score in 9 intensive care unit (ICU) patients with acute respiratory failure was 30 (interquartile range 25-32). Standardized quantitative assessment of HLA-DR on monocytes (cluster of differentiation 14+ cells) was performed using calibrated flow cytometry at baseline (ICU/hospital admission) and at days 3 and 5 after ICU admission. Baseline data were compared to hospitalized noncritically ill COVID-19 patients. RESULTS: While normal mHLA-DR expression was observed in all hospitalized noncritically ill patients (n = 7), 89% (8 of 9) critically ill patients with COVID-19-induced acute respiratory failure showed signs of downregulation of mHLA-DR at ICU admission. mHLA-DR expression at admission was significantly lower in critically ill patients (median, [quartiles]: 9280 antibodies/cell [6114, 16,567]) as compared to the noncritically ill patients (30,900 antibodies/cell [26,777, 52,251]), with a median difference of 21,508 antibodies/cell (95% confidence interval [CI], 14,118-42,971), P = .002. Reduced mHLA-DR expression was observed to persist until day 5 after ICU admission. CONCLUSIONS: When compared to noncritically ill hospitalized COVID-19 patients, ICU patients with severe COVID-19 disease showed reduced mHLA-DR expression on circulating CD14+ monocytes at ICU admission, indicating a dysfunctional immune response. This immunosuppressive (monocytic) phenotype remained unchanged over the ensuing days after ICU admission. Strategies aiming for immunomodulation in this population of critically ill patients should be guided by an immune-monitoring program in an effort to determine who might benefit best from a given immunological intervention.


Assuntos
Infecções por Coronavirus/imunologia , Estado Terminal , Antígenos HLA-DR/biossíntese , Antígenos HLA-DR/imunologia , Tolerância Imunológica/imunologia , Pneumonia Viral/imunologia , APACHE , Idoso , Anticorpos/análise , Anticorpos/imunologia , Infecções por Coronavirus/terapia , Cuidados Críticos , Regulação para Baixo/imunologia , Feminino , Humanos , Imunoterapia , Receptores de Lipopolissacarídeos/imunologia , Masculino , Pessoa de Meia-Idade , Monócitos/imunologia , Pandemias , Pneumonia Viral/terapia , Estudos Prospectivos , Insuficiência Respiratória/imunologia , Insuficiência Respiratória/fisiopatologia
6.
N Engl J Med ; 383(12): 1149-1155, 2020 09 17.
Artigo em Inglês | MEDLINE | ID: mdl-32937047

RESUMO

Daratumumab, a human monoclonal antibody that targets CD38, depletes plasma cells and is approved for the treatment of multiple myeloma. Long-lived plasma cells are implicated in the pathogenesis of systemic lupus erythematosus because they secrete autoantibodies, but they are unresponsive to standard immunosuppression. We describe the use of daratumumab that induced substantial clinical responses in two patients with life-threatening lupus, with the clinical responses sustained by maintenance therapy with belimumab, an antibody to B-cell activating factor. Significant depletion of long-lived plasma cells, reduction of interferon type I activity, and down-regulation of T-cell transcripts associated with chronic inflammation were documented. (Supported by the Deutsche Forschungsgemeinschaft and others.).


Assuntos
ADP-Ribosil Ciclase 1/antagonistas & inibidores , Anticorpos Monoclonais/uso terapêutico , Imunossupressores/uso terapêutico , Lúpus Eritematoso Sistêmico/tratamento farmacológico , Glicoproteínas de Membrana/antagonistas & inibidores , Plasmócitos/efeitos dos fármacos , ADP-Ribosil Ciclase 1/metabolismo , Adulto , Anticorpos Monoclonais Humanizados/uso terapêutico , Creatinina/sangue , Creatinina/urina , Regulação para Baixo , Feminino , Humanos , Interferon Tipo I/antagonistas & inibidores , Quimioterapia de Manutenção , Glicoproteínas de Membrana/metabolismo , Pessoa de Meia-Idade , Proteinúria , Linfócitos T/efeitos dos fármacos , Linfócitos T/metabolismo
7.
Ecotoxicol Environ Saf ; 203: 111019, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-32888606

RESUMO

Sulfur dioxide (SO2) is one of the most common and harmful air pollutants. High concentrations of SO2 can induce a series of defensive responses in Arabidopsis plants. However, the role of photosynthesis in the plant response to SO2 stress is not clear. Here, we report the photosynthetic responses of Arabidopsis plants to SO2 stress. Exposure to 30 mg/m3 SO2 decreased stomatal conductance (Gs) and transpiration rate (Tr) but increased photosynthetic pigments and net photosynthetic rate (Pn). The contents of carbohydrates and sucrose were not altered. The transcript levels of most genes related to photosystem II (PSII), cytochrome b6/f (Cytb6f), photosystem I (PSI) and carbon fixation were upregulated, revealing one important regulatory circuit for the maintenance of chloroplast homeostasis under SO2 stress. Exposure to SO2 triggered reactive oxygen species (ROS) generation, accompanied by increases in superoxide dismutase (SOD) activity and the contents of cysteine (Cys), glutathione (GSH) and non-protein thiol (NPT), which maintained cellular redox homeostasis. Together, our results indicated that chloroplast photosynthesis was involved in the plant response to SO2 stress. The photosynthetic responses were related to photosynthetic pigments, photosynthesis gene expression and redox regulation.


Assuntos
Poluentes Atmosféricos/toxicidade , Arabidopsis/efeitos dos fármacos , Expressão Gênica/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Fotossíntese/efeitos dos fármacos , Pigmentos Biológicos/metabolismo , Dióxido de Enxofre/toxicidade , Arabidopsis/genética , Arabidopsis/metabolismo , Cloroplastos/metabolismo , Regulação para Baixo , Fotossíntese/genética , Complexo de Proteína do Fotossistema I/metabolismo , Complexo de Proteína do Fotossistema II/metabolismo , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/metabolismo , Regulação para Cima
8.
PLoS One ; 15(9): e0238301, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32881954

RESUMO

BACKGROUND: Neuromyelitis optica spectrum disorders (NMOSD) is a primary astrocytopathy driven by antibodies directed against the aquaporin-4 water channel located at the end-feet of the astrocyte. Although blood-brain barrier (BBB) breakdown is considered one of the key steps for the development and lesion formation, little is known about the molecular mechanisms involved. The aim of the study was to evaluate the effect of human immunoglobulins from NMOSD patients (NMO-IgG) on BBB properties. METHODS: Freshly isolated brain microvessels (IBMs) from rat brains were used as a study model. At first, analysis of the secretome profile from IBMs exposed to purified NMO-IgG, to healthy donor IgG (Control-IgG), or non-treated, was performed. Second, tight junction (TJ) proteins expression in fresh IBMs and primary cultures of brain microvascular endothelial cells (BMEC) was analysed by Western blotting (Wb) after exposition to NMO-IgG and Control-IgG. Finally, functional BBB properties were investigated evaluating the presence of rat-IgG in tissue lysate from brain using Wb in the rat-model, and the passage of NMO-IgG and sucrose in a bicameral model. RESULTS: We found that NMO-IgG induces functional and morphological BBB changes, including: 1) increase of pro-inflammatory cytokines production (CXCL-10 [IP-10], IL-6, IL-1RA, IL-1ß and CXCL-3) in IBMs when exposed to NMO-IgG; 2) decrease of Claudin-5 levels by 25.6% after treatment of fresh IBMs by NMO-IgG compared to Control-IgG (p = 0.002), and similarly, decrease of Claudin-5 by at least 20% when BMEC were cultured with NMO-IgG from five different patients; 3) a higher level of rat-IgG accumulated in periventricular regions of NMO-rats compared to Control-rats and an increase in the permeability of BBB after NMO-IgG treatment in the bicameral model. CONCLUSION: Human NMO-IgG induces both structural and functional alterations of BBB properties, suggesting a direct role of NMO-IgG on modulation of BBB permeability in NMOSD.


Assuntos
Aquaporina 4/imunologia , Barreira Hematoencefálica/metabolismo , Imunoglobulina G/farmacologia , Neuromielite Óptica/patologia , Permeabilidade/efeitos dos fármacos , Animais , Barreira Hematoencefálica/efeitos dos fármacos , Células Cultivadas , Quimiocinas/metabolismo , Claudina-5/metabolismo , Citocinas/metabolismo , Modelos Animais de Doenças , Regulação para Baixo/efeitos dos fármacos , Células Endoteliais/citologia , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/metabolismo , Humanos , Imunoglobulina G/isolamento & purificação , Microvasos/citologia , Microvasos/metabolismo , Neuromielite Óptica/metabolismo , Ratos
9.
BMJ Open ; 10(9): e040644, 2020 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-32928868

RESUMO

OBJECTIVE: To review evidence on routinely prescribed drugs in the UK that could upregulate or downregulate ACE2 and potentially affect COVID-19 disease. DESIGN: Systematic review. DATA SOURCE: MEDLINE, EMBASE, CINAHL, the Cochrane Library and Web of Science. STUDY SELECTION: Any design with animal or human models examining a currently prescribed UK drug compared with a control, placebo or sham group, and reporting an effect on ACE2 level, activity or gene expression. DATA EXTRACTION AND SYNTHESIS: MEDLINE, EMBASE, CINAHL, the Cochrane Library, Web of Science and OpenGrey from inception to 1 April 2020. Methodological quality was assessed using the SYstematic Review Centre for Laboratory animal Experimentation (SYRCLE) risk-of-bias tool for animal studies and Cochrane risk-of-bias tool for human studies. RESULTS: We screened 3360 titles and included 112 studies with 21 different drug classes identified as influencing ACE2 activity. Ten studies were in humans and one hundred and two were in animal models None examined ACE2 in human lungs. The most frequently examined drugs were angiotensin receptor blockers (ARBs) (n=55) and ACE inhibitors (ACE-I) (n=22). More studies reported upregulation than downregulation with ACE-I (n=22), ARBs (n=55), insulin (n=8), thiazolidinedione (n=7) aldosterone agonists (n=3), statins (n=5), oestrogens (n=5) calcium channel blockers (n=3) glucagon-like peptide 1 (GLP-1) agonists (n=2) and Non-steroidal anti-inflammatory drugs (NSAIDs) (n=2). CONCLUSIONS: There is an abundance of the academic literature and media reports on the potential of drugs that could attenuate or exacerbate COVID-19 disease. This is leading to trials of repurposed drugs and uncertainty among patients and clinicians concerning continuation or cessation of prescribed medications. Our review indicates that the impact of currently prescribed drugs on ACE2 has been poorly studied in vivo, particularly in human lungs where the SARS-CoV-2 virus appears to enact its pathogenic effects. We found no convincing evidence to justify starting or stopping currently prescribed drugs to influence outcomes of COVID-19 disease.


Assuntos
Antagonistas de Receptores de Angiotensina/farmacologia , Inibidores da Enzima Conversora de Angiotensina/farmacologia , Bloqueadores dos Canais de Cálcio/farmacologia , Infecções por Coronavirus , Estrogênios/farmacologia , Inibidores de Hidroximetilglutaril-CoA Redutases/farmacologia , Hipoglicemiantes/farmacologia , Pandemias , Peptidil Dipeptidase A/efeitos dos fármacos , Pneumonia Viral , Anti-Inflamatórios não Esteroides/farmacologia , Betacoronavirus/metabolismo , Regulação para Baixo , Peptídeo 1 Semelhante ao Glucagon/agonistas , Humanos , Insulina/farmacologia , Antagonistas de Receptores de Mineralocorticoides/farmacologia , Peptidil Dipeptidase A/metabolismo , Tiazolidinedionas/farmacologia , Reino Unido , Regulação para Cima
10.
Medicine (Baltimore) ; 99(38): e22241, 2020 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-32957369

RESUMO

BACKGROUND: Quercetin, a major flavonol, wildly exists in plantage, which has been reported to have an anti-apoptosis and anti-inflammation effects on vascular endothelial cells, but its underlying molecular mechanisms remain unclear. OBJECTIVE: The aim of this study was to investigate the mechanisms of how quercetin inhibits tumor necrosis factor alpha (TNF-α) induced human umbilical vein endothelial cells (HUVECs) apoptosis and inflammation. METHODS AND RESULTS: HUVECs were preconditioned with quercetin for 18 hours, and subsequently treated with TNF-α for 6 hours to induce apoptosis. The expression of intercellular cell adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule 1 (VCAM-1), E-selectin, ß-actin mRNA was then detected by RT-PCR. Flow cytometry was used to estimate the apoptosis rates, and the expression of activator protein 1 (AP-1) and nuclear factor kappa B (NF-κB) was measured by Western blot. TNF-α induced elevated apoptosis rates and upregulation of VCAM-1, ICAM-1, and E-selectin were meaningfully reduced in HUVECs by pretreatment with quercetin. In addition, quercetin also inhibited the activation of AP-1and NF-κB. CONCLUSION: Results indicate that quercetin could suppress TNF-α induced apoptosis and inflammation by blocking NF-κB and AP-1 signaling pathway in HUVECs, which might be one of the underlying mechanisms in treatment of coronary heart disease.


Assuntos
Anti-Inflamatórios/farmacologia , Apoptose/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/citologia , Inflamação/prevenção & controle , NF-kappa B/metabolismo , Quercetina/farmacologia , Fator de Transcrição AP-1/metabolismo , Regulação para Baixo , Selectina E/metabolismo , Humanos , Inflamação/metabolismo , Inflamação/patologia , Molécula 1 de Adesão Intercelular/metabolismo , Transdução de Sinais , Fator de Necrose Tumoral alfa/farmacologia , Molécula 1 de Adesão de Célula Vascular/metabolismo
11.
Medicine (Baltimore) ; 99(39): e22172, 2020 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-32991410

RESUMO

Osteoporosis is a severe chronic skeletal disorder that increases the risks of disability and mortality; however, the mechanism of this disease and the protein markers for prognosis of osteoporosis have not been well characterized. This study aims to characterize the imbalanced serum proteostasis, the disturbed pathways, and potential serum markers in osteoporosis by using a set of bioinformatic analyses. In the present study, the large-scale proteomics datasets (PXD006464) were adopted from the Proteome Xchange database and processed with MaxQuant. The differentially expressed serum proteins were identified. The biological process and molecular function were analyzed. The protein-protein interactions and subnetwork modules were constructed. The signaling pathways were enriched. We identified 209 upregulated and 230 downregulated serum proteins. The bioinformatic analyses revealed a highly overlapped functional protein classification and the gene ontology terms between the upregulated and downregulated protein groups. Protein-protein interactions and pathway analyses showed a high enrichment in protein synthesis, inflammation, and immune response in the upregulated proteins, and cell adhesion and cytoskeleton regulation in the downregulated proteins. Our findings greatly expand the current view of the roles of serum proteins in osteoporosis and shed light on the understanding of its underlying mechanisms and the discovery of serum proteins as potential markers for the prognosis of osteoporosis.


Assuntos
Mineração de Dados/métodos , Osteoporose/sangue , Proteoma/fisiologia , Biomarcadores , Adesão Celular/fisiologia , Biologia Computacional , Citoesqueleto/metabolismo , Regulação para Baixo , Humanos , Mediadores da Inflamação/metabolismo , Mapas de Interação de Proteínas/fisiologia , Proteômica , Regulação para Cima
12.
Anticancer Res ; 40(9): 4895-4905, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32878777

RESUMO

BACKGROUND/AIM: Nicotinamide phosphoribosyl-transferase (NAMPT) is a rate-limiting enzyme in the pathway synthesizing nicotinamide adenine dinucleotide (NAD (+)) from nicotinamide (NAM). Glioma tissues exhibit up-regulated NAMPT expression associated with a poor prognosis of patients. To determine if NAMPT can be a molecular therapeutic target, we investigated the effects of short hairpin RNA (shRNA)-mediated NAMPT down-regulation. MATERIALS AND METHODS: We designed shRNA to NAMPT and transfected to T98G cells. The characteristics of these cells were analyzed. RESULTS: The NAMPT shRNA-transfected cells exhibited delayed cell growth. However, there was no difference in the increase of sensitivity to temozolomide (TMZ) or X-ray irradiation between the NAMPT and scramble shRNA-transfected cells. The expression of NAMPT in the NAMPT shRNA-transfected cells increased with cell passage. Additionally, the shRNA-mediated transfection was associated with enhanced expression of quinolinic acid phosphoribo-syltransferase (QPRT). CONCLUSION: shRNA-mediated NAMPT down-regulation may not decrease the NADt to a sufficient level to increase TMZ/radiation sensitivity.


Assuntos
Citocinas/metabolismo , Regulação para Baixo , Glioma/enzimologia , Nicotinamida Fosforribosiltransferase/metabolismo , Antineoplásicos Alquilantes/farmacologia , Linhagem Celular Tumoral , Proliferação de Células , Citocinas/genética , Glioma/metabolismo , Glioma/patologia , Humanos , NAD/metabolismo , Nicotinamida Fosforribosiltransferase/genética , Pentosiltransferases/genética , Pentosiltransferases/metabolismo , RNA Interferente Pequeno/genética , Temozolomida/farmacologia
13.
Nan Fang Yi Ke Da Xue Xue Bao ; 40(8): 1090-1096, 2020 Aug 30.
Artigo em Chinês | MEDLINE | ID: mdl-32895173

RESUMO

OBJECTIVE: To investigate the effect of down-regulation of pannexin 2 (Panx-2) channels on cisplatin-induced apoptosis in I-10 cells. METHODS: The expression of Panx-2 protein in testicular cancer cells was detected with Western blotting. The testicular cancer cell line I-10 was transfected with two short hairpin RNA (shRNA1 and shRNA2) via Lipofectamine2000, the empty vector (NC group) or Lipofectamine2000 (blank control group), and the changes in the expression of Panx-2 was detected with Western blotting. The effects of transfection with a Panx-2 inhibitor on surviving fraction of the cells treated with cisplatin (16 µmol/L) for 24 h, 48 h and 72 h was assessed with MTT assay, and the clonogenic capacity of the cells was evaluated with colony-forming assay. At 8 h after incubation with 16 µmol/L cisplatin, AnnexinV/PI double staining was used to detect the early apoptosis of the cells. After 24 h of treatment with 16 µmol/L cisplatin, the cells were examined for expressions of caspase-3, Bcl-2 and Bax using Western blotting. RESULTS: The expression of Panx-2 was significantly increased in cisplatin-resistant I-10/DDP (P < 0.001) cells and Tcam-2/DDP (P < 0.01) cells as compared with I-10 cells and Tcam-2 cells. Transfection of I-10 cells with shRNA1 and shRNA2 resulted in significantly decreased Panx-2 expression (P < 0.05) and significantly reduced cell surviving fraction (P < 0.001). In the presence of cisplatin, the cells in NC group showed a higher clonogenic efficiency than those in shRNA1 and shRNA2 groups (P < 0.001). The early-stage apoptosis rate of the cells in shRNA1 and shRNA2 groups were significantly higher than that in NC group (P < 0.01). Panx-2 knockdown in I-10 cells significantly increased caspase-3 and Bax expressions (P < 0.05) and significantly decreased the expression of Bcl-2 (P < 0.01). CONCLUSIONS: Down-regulation of Panx-2 channel enhances cisplatin-induced apoptosis in cultured testicular cancer cells.


Assuntos
Neoplasias Testiculares , Antineoplásicos , Apoptose , Linhagem Celular Tumoral , Proliferação de Células , Cisplatino , Conexinas , Regulação para Baixo , Resistencia a Medicamentos Antineoplásicos , Humanos , Masculino
14.
Nat Commun ; 11(1): 4454, 2020 09 08.
Artigo em Inglês | MEDLINE | ID: mdl-32901001

RESUMO

Chronic viral infections are often associated with impaired CD8+ T cell function, referred to as exhaustion. Although the molecular and cellular circuits involved in CD8+ T cell exhaustion are well defined, with sustained presence of antigen being one important parameter, how much T cell receptor (TCR) signaling is actually ongoing in vivo during established chronic infection is unclear. Here, we characterize the in vivo TCR signaling of virus-specific exhausted CD8+ T cells in a mouse model, leveraging TCR signaling reporter mice in combination with transcriptomics. In vivo signaling in exhausted cells is low, in contrast to their in vitro signaling potential, and despite antigen being abundantly present. Both checkpoint blockade and adoptive transfer of naïve target cells increase TCR signaling, demonstrating that engagement of co-inhibitory receptors curtails CD8+ T cell signaling and function in vivo.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Coriomeningite Linfocítica/imunologia , Receptores de Antígenos de Linfócitos T/imunologia , Transferência Adotiva , Animais , Antígeno B7-H1/antagonistas & inibidores , Antígeno B7-H1/imunologia , Linfócitos T CD8-Positivos/virologia , Doença Crônica , Citotoxicidade Imunológica , Modelos Animais de Doenças , Regulação para Baixo , Tolerância Imunológica , Imunidade Celular , Técnicas In Vitro , Ativação Linfocitária , Coriomeningite Linfocítica/genética , Vírus da Coriomeningite Linfocítica/imunologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Membro 1 do Grupo A da Subfamília 4 de Receptores Nucleares/genética , Membro 1 do Grupo A da Subfamília 4 de Receptores Nucleares/imunologia , Receptor de Morte Celular Programada 1/imunologia , RNA-Seq , Transdução de Sinais/imunologia
15.
BMJ Open Respir Res ; 7(1)2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32913008

RESUMO

We and others propose vimentin as a possible cellular target for the treatment of COVID-19. This innovative idea is so recent that it requires further attention and debate. The significant role played by vimentin in virus-induced infection however is well established: (1) vimentin has been reported as a co-receptor and/or attachment site for SARS-CoV; (2) vimentin is involved in viral replication in cells; (3) vimentin plays a fundamental role in both the viral infection and the consequent explosive immune-inflammatory response and (4) a lower vimentin expression is associated with the inhibition of epithelial to mesenchymal transition and fibrosis. Moreover, the absence of vimentin in mice makes them resistant to lung injury. Since vimentin has a twofold role in the disease, not only being involved in the viral infection but also in the associated life-threatening lung inflammation, the use of vimentin-targeted drugs may offer a synergistic advantage as compared with other treatments not targeting vimentin. Consequently, we speculate here that drugs which decrease the expression of vimentin can be used for the treatment of patients with COVID-19 and advise that several Food and Drug Administration-approved drugs be immediately tested in clinical trials against SARS-CoV-2, thus broadening therapeutic options for this type of viral infection.


Assuntos
Antivirais/farmacologia , Betacoronavirus/fisiologia , Infecções por Coronavirus , Pandemias , Pneumonia Viral , Vimentina/fisiologia , Internalização do Vírus/efeitos dos fármacos , Animais , Infecções por Coronavirus/tratamento farmacológico , Infecções por Coronavirus/metabolismo , Infecções por Coronavirus/virologia , Regulação para Baixo , Descoberta de Drogas/métodos , Humanos , Camundongos , Pneumonia/tratamento farmacológico , Pneumonia/imunologia , Pneumonia/metabolismo , Pneumonia Viral/tratamento farmacológico , Pneumonia Viral/metabolismo , Pneumonia Viral/virologia , Receptores Virais , Replicação Viral/fisiologia
16.
Medicine (Baltimore) ; 99(37): e21963, 2020 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-32925730

RESUMO

This study aims to identify differentially expressed microRNAs (miRNAs) in gastric cancer by comparing gastric cancerous tissues with normal tissues, explore the potential roles.The miRNA expression microarray was employed on gastric cancer tissues, and apparently normal para-cancerous tissues from 3 patients undergoing radical surgery were matched. Quantitative RT-PCR was performed on the other 7 patients to validate the findings of the microarray. Furthermore, Gene Ontology (GO) analysis and enrichment analysis of KEGG Pathway were performed for 5 dysregulated candidate miRNAs, including 3 upregulated (miR-31-3p, miR-6736-3p, and miR-147b) and 2 downregulated (miR-3065-5p and miR-3921) miRNAs, in order to determine the role of miRNAs in tumorigenesis and development.Among these miRNAs, 17 miRNAs were found to be upregulated, and 19 miRNAs were found to be downregulated. The dysregulated expression of 5 candidate miRNAs, including miR-31-3p, miR-147b, miR-6736-3p, miR-3065-5p, and miR-3921, were verified by quantitative RT-PCR in the validation set. Among these miRNAs, miR-31-3p, miR-6736-3p, miR-3065-5p, and miR-3921 had 551 target gene intersections. The GO and KEGG Pathway analyses Revealed that miR-31-3p, miR-6736-3p, miR-3065-5p, and miR-3921 may participate in multiple pathophysiological processes, such as foreign substance metabolism and chemical carcinogenesis.The profile of differentially expressed miRNAs was successfully screened, and 4 miRNAs (i.e., miR-31-3p, miR-6736-3p, miR-3065-5p, and miR-3921) appeared to be involved in gastric carcinogenesis. These might serve as promising biomarkers for gastric cancer.


Assuntos
Perfilação da Expressão Gênica , MicroRNAs/genética , Neoplasias Gástricas/diagnóstico , Neoplasias Gástricas/genética , Regulação para Baixo , Regulação Neoplásica da Expressão Gênica , Humanos , Reação em Cadeia da Polimerase em Tempo Real , Regulação para Cima
17.
Elife ; 92020 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-32930095

RESUMO

Obesity and diabetes are established comorbidities for COVID-19. Adipose tissue demonstrates high expression of ACE2 which SARS- CoV-2 exploits to enter host cells. This makes adipose tissue a reservoir for SARS-CoV-2 viruses and thus increases the integral viral load. Acute viral infection results in ACE2 downregulation. This relative deficiency can lead to disturbances in other systems controlled by ACE2, including the renin-angiotensin system. This will be further increased in the case of pre-conditions with already compromised functioning of these systems, such as in patients with obesity and diabetes. Here, we propose that interactions of virally-induced ACE2 deficiency with obesity and/or diabetes leads to a synergistic further impairment of endothelial and gut barrier function. The appearance of bacteria and/or their products in the lungs of obese and diabetic patients promotes interactions between viral and bacterial pathogens, resulting in a more severe lung injury in COVID-19.


Assuntos
Infecções por Coronavirus/microbiologia , Diabetes Mellitus/microbiologia , Obesidade/microbiologia , Pneumonia Viral/microbiologia , Tecido Adiposo/metabolismo , Tecido Adiposo/virologia , Animais , Betacoronavirus/isolamento & purificação , Comorbidade , Infecções por Coronavirus/complicações , Infecções por Coronavirus/metabolismo , Infecções por Coronavirus/virologia , Complicações do Diabetes/metabolismo , Complicações do Diabetes/microbiologia , Complicações do Diabetes/virologia , Diabetes Mellitus/metabolismo , Diabetes Mellitus/virologia , Regulação para Baixo , Interações entre Hospedeiro e Microrganismos , Humanos , Interações Microbianas , Obesidade/metabolismo , Obesidade/virologia , Pandemias , Peptidil Dipeptidase A/metabolismo , Pneumonia Viral/complicações , Pneumonia Viral/metabolismo , Pneumonia Viral/virologia , Sistema Renina-Angiotensina , Carga Viral
18.
Nat Commun ; 11(1): 4589, 2020 09 11.
Artigo em Inglês | MEDLINE | ID: mdl-32917887

RESUMO

Mandibuloacral dysplasia syndromes are mainly due to recessive LMNA or ZMPSTE24 mutations, with cardinal nuclear morphological abnormalities and dysfunction. We report five homozygous null mutations in MTX2, encoding Metaxin-2 (MTX2), an outer mitochondrial membrane protein, in patients presenting with a severe laminopathy-like mandibuloacral dysplasia characterized by growth retardation, bone resorption, arterial calcification, renal glomerulosclerosis and severe hypertension. Loss of MTX2 in patients' primary fibroblasts leads to loss of Metaxin-1 (MTX1) and mitochondrial dysfunction, including network fragmentation and oxidative phosphorylation impairment. Furthermore, patients' fibroblasts are resistant to induced apoptosis, leading to increased cell senescence and mitophagy and reduced proliferation. Interestingly, secondary nuclear morphological defects are observed in both MTX2-mutant fibroblasts and mtx-2-depleted C. elegans. We thus report the identification of a severe premature aging syndrome revealing an unsuspected link between mitochondrial composition and function and nuclear morphology, establishing a pathophysiological link with premature aging laminopathies and likely explaining common clinical features.


Assuntos
Acro-Osteólise/metabolismo , Predisposição Genética para Doença/genética , Lipodistrofia/metabolismo , Mandíbula/anormalidades , Proteínas de Membrana/metabolismo , Mitocôndrias/metabolismo , Proteínas Mitocondriais/metabolismo , Acro-Osteólise/diagnóstico por imagem , Acro-Osteólise/genética , Acro-Osteólise/patologia , Senilidade Prematura/genética , Senilidade Prematura/metabolismo , Animais , Apoptose , Caenorhabditis elegans , Proliferação de Células , Criança , Regulação para Baixo , Feminino , Fibroblastos/metabolismo , Fibroblastos/patologia , Regulação da Expressão Gênica , Genótipo , Homozigoto , Humanos , Lipodistrofia/diagnóstico por imagem , Lipodistrofia/genética , Lipodistrofia/patologia , Masculino , Mandíbula/diagnóstico por imagem , Proteínas de Membrana/genética , Metaloendopeptidases , Proteínas de Transporte da Membrana Mitocondrial/genética , Proteínas Mitocondriais/genética , Mutação , Fenótipo , Pele , Sequenciamento Completo do Genoma
19.
Int J Nanomedicine ; 15: 6355-6372, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32922006

RESUMO

Background: Cerium oxide nanoparticles (CeO2NPs) are potent scavengers of cellular reactive oxygen species (ROS). Their antioxidant properties make CeO2NPs promising therapeutic agents for bone diseases and bone tissue engineering. However, the effects of CeO2NPs on intracellular ROS production in osteoclasts (OCs) are still unclear. Numerous studies have reported that intracellular ROS are essential for osteoclastogenesis. The aim of this study was to explore the effects of CeO2NPs on osteoclast differentiation and the potential underlying mechanisms. Methods: The bidirectional modulation of osteoclast differentiation by CeO2NPs was explored by different methods, such as fluorescence microscopy, scanning electron microscopy (SEM), transmission electron microscopy (TEM), quantitative real-time polymerase chain reaction (qRT-PCR), and Western blotting. The cytotoxic and proapoptotic effects of CeO2NPs were detected by cell counting kit (CCK-8) assay, TdT-mediated dUTP nick-end labeling (TUNEL) assay, and flow cytometry. Results: The results of this study demonstrated that although CeO2NPs were capable of scavenging ROS in acellular environments, they facilitated the production of ROS in the acidic cellular environment during receptor activator of nuclear factor kappa-Β ligand (RANKL)-dependent osteoclast differentiation of bone marrow-derived macrophages (BMMs). CeO2NPs at lower concentrations (4.0 µg/mL to 8.0 µg/mL) promoted osteoclast formation, as shown by increased expression of Nfatc1 and C-Fos, F-actin ring formation and bone resorption. However, at higher concentrations (greater than 16.0 µg/mL), CeO2NPs inhibited osteoclast differentiation and promoted apoptosis of BMMs by reducing Bcl2 expression and increasing the expression of cleaved caspase-3, which may be due to the overproduction of ROS. Conclusion: This study demonstrates that CeO2NPs facilitate osteoclast formation at lower concentrations while inhibiting osteoclastogenesis in vitro by inducing the apoptosis of BMMs at higher concentrations by modulating cellular ROS levels.


Assuntos
Diferenciação Celular , Cério/química , Osteoclastos/citologia , Espécies Reativas de Oxigênio/metabolismo , Actinas/metabolismo , Animais , Apoptose/efeitos dos fármacos , Apoptose/genética , Células da Medula Óssea/citologia , Células da Medula Óssea/efeitos dos fármacos , Reabsorção Óssea/metabolismo , Diferenciação Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Regulação para Baixo/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Macrófagos/citologia , Macrófagos/efeitos dos fármacos , Macrófagos/ultraestrutura , Masculino , Camundongos Endogâmicos C57BL , NF-kappa B/metabolismo , Nanopartículas/ultraestrutura , Osteoclastos/efeitos dos fármacos , Osteogênese/efeitos dos fármacos , Ligante RANK/farmacologia , Transdução de Sinais/efeitos dos fármacos , Regulação para Cima/efeitos dos fármacos
20.
Ecotoxicol Environ Saf ; 205: 111339, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-32961491

RESUMO

Famoxadone-cymoxanil is a new protective and therapeutic fungicide, but little research has been done on it or its toxicity in aquatic organisms. In this study, we used zebrafish to investigate the cardiotoxicity of famoxadone-cymoxanil and the potential mechanisms involved. Zebrafish embryos were exposed to different concentrations of famoxadone-cymoxanil until 72 h post-fertilization (hpf), then changes of heart morphology in zebrafish embryos were observed. We also detected the levels of oxidative stress, myocardial-cell proliferation and apoptosis, ATPase activity, and the expression of genes related to the cardiac development and calcium-signaling pathway. After famoxadone-cymoxanil exposure, pericardial edema, cardiac linearization, and reductions in the heart rate and cardiac output positively correlated with concentration. Although myocardial-cell apoptosis was not detected, proliferation of the cells was severely reduced and ATPase activity significantly decreased, resulting in a severe deficiency in heart function. In addition, indicators of oxidative stress changed significantly after exposure of the embryos to the fungicide. To better understand the possible molecular mechanisms of cardiovascular toxicity in zebrafish, we studied the transcriptional levels of cardiac development, calcium-signaling pathways, and genes associated with myocardial contractility. The mRNA expression levels of key genes in heart development were significantly down-regulated, while the expression of genes related to the calcium-signaling pathway (ATPase [atp2a1], cardiac troponin C [tnnc1a], and calcium channel [cacna1a]) was significantly inhibited. Expression of klf2a, a major endocardial flow-responsive gene, was also significantly inhibited. Mechanistically, famoxadone-cymoxanil toxicity might be due to the downregulation of genes associated with the calcium-signaling pathway and cardiac muscle contraction. Our results found that famoxadone-cymoxanil exposure causes cardiac developmental toxicity and severe energy deficiency in zebrafish.


Assuntos
Acetamidas/toxicidade , Embrião não Mamífero/efeitos dos fármacos , Fungicidas Industriais/toxicidade , Coração/efeitos dos fármacos , Estrobilurinas/toxicidade , Poluentes Químicos da Água/toxicidade , Peixe-Zebra/metabolismo , Animais , Apoptose/efeitos dos fármacos , Sinalização do Cálcio/efeitos dos fármacos , Sinalização do Cálcio/genética , Cardiotoxicidade , Regulação para Baixo , Embrião não Mamífero/metabolismo , Embrião não Mamífero/patologia , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Coração/embriologia , Frequência Cardíaca/efeitos dos fármacos , Fatores de Transcrição Kruppel-Like/genética , Fatores de Transcrição Kruppel-Like/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Peixe-Zebra/crescimento & desenvolvimento , Proteínas de Peixe-Zebra/genética , Proteínas de Peixe-Zebra/metabolismo
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