RESUMO
MicroRNAs (miRNAs) are potential biomarkers for cancer diagnosis and prognosis, methods for detecting miRNAs with high sensitivity, selectivity, and stability are urgently needed. Various nucleic acid probes that have traditionally been for this purpose suffer several drawbacks, including inefficient signal-to-noise ratios and intensities, high cost, and time-consuming method establishment. Computing tools used for investigating the thermodynamics of DNA hybridization reactions can accurately predict the secondary structure of DNA and the interactions between DNA molecules. Herein, NUPACK was used to design a series of nucleic acid probes and develop a phosphorothioated-terminal hairpin formation and self-priming extension (PS-THSP) signal amplification strategy, which enabled the ultrasensitive detection of miR-200a in serum samples. The free and binding energies of the DNA detection probes calculated using NUPACK, as well as the biological experimental results, were considered synthetically to select the best sequence and experimental conditions. A unified dynamic programming framework, NUPACK analysis and the experimental data, were complementary and improved the designed model in all respects. Our study demonstrates the feasibility of using computer technology such as NUPACK to simplify the experimental process and provide intuitive results.
Assuntos
MicroRNAs , Ácidos Nucleicos , Sondas de DNA/genética , MicroRNAs/genética , Razão Sinal-Ruído , TermodinâmicaRESUMO
AIMS: FoxO1 is an important target in the treatment of Alzheimer's disease (AD). However, FoxO1-specific agonists and their effects on AD have not yet been reported. This study aimed to identify small molecules that upregulate the activity of FoxO1 to attenuate the symptoms of AD. METHODS: FoxO1 agonists were identified by in silico screening and molecular dynamics simulation. Western blotting and reverse transcription-quantitative polymerase chain reaction assays were used to assess protein and gene expression levels of P21, BIM, and PPARγ downstream of FoxO1 in SH-SY5Y cells, respectively. Western blotting and enzyme-linked immunoassays were performed to explore the effect of FoxO1 agonists on APP metabolism. RESULTS: N-(3-methylisothiazol-5-yl)-2-(2-oxobenzo[d]oxazol-3(2H)-yl) acetamide (compound D) had the highest affinity for FoxO1. Compound D activated FoxO1 and regulated the expression of its downstream target genes, P21, BIM, and PPARγ. In SH-SY5Y cells treated with compound D, BACE1 expression levels were downregulated, and the levels of Aß1-40 and Aß1-42 were also reduced. CONCLUSIONS: We present a novel small-molecule FoxO1 agonist with good anti-AD effects. This study highlights a promising strategy for new drug discovery for AD.
Assuntos
Doença de Alzheimer , Neuroblastoma , Humanos , Doença de Alzheimer/tratamento farmacológico , Peptídeos beta-Amiloides/metabolismo , Secretases da Proteína Precursora do Amiloide/genética , Ácido Aspártico Endopeptidases/genética , Ácido Aspártico Endopeptidases/metabolismo , Regulação para Baixo , PPAR gama/genéticaRESUMO
BACKGROUND: Long noncoding RNAs (lncRNAs) and microRNAs (miRNAs) have been reported to play regulatory roles in ulcerative colitis (UC). In this study, we aimed to determine the specific roles and action mechanism of the nuclear paraspeckle assembly transcript 1 (NEAT1) in UC. METHODS: Reverse transcription-quantitative polymerase chain reaction (RT-qPCR) was used to determine the lncRNA NEAT1 and miR-493-5p expression levels in patients with UC and healthy volunteers. We determine the forecast linkage points of NEAT1 and miR-493-5p using Starbase and those of miR-493-5p and Rab27A using TargetScan, and further verified them using a double luciferase gene reporter kit. RT-qPCR and Western blot analysis were used to determine the lncRNA NEAT1, miR-493-5p, and Rab27A expression levels in lipopolysaccharide (LPS)-induced Caco-2 cells. Flow cytometry and cell counting kit-8 were used to assess Caco-2 cell viability. Tumor necrosis factor-α, interleukin (IL)-6, IL-8, and IL-1ß levels were determined via an enzyme-linked immunosorbent assay. RESULTS: Expression levels of NEAT1 were upregulated and those of miR-493-5p were downregualted in 10 ng/mL LPS-treated Caco-2 cells and patients with UC. Dual-luciferase gene reporter assay revealed that miR-493-5p is linked to NEAT1, and Rab27A is a downstream target of miR-493-5p. Overexpression of miR-493-5p inhibited the apoptosis and inflammation in LPS-treated Caco-2 cells. Moreover, downregulation of lncRNA NEAT1 expression also inhibited the apoptosis and inflammation in LPS-treated Caco-2 cells, which was reversed by Rab27A plasmid cotransfection. CONCLUSION: Our results revealed that NEAT1 participates in UC progression by inhibiting miR-493-5p expression.
Assuntos
Colite Ulcerativa , MicroRNAs , RNA Longo não Codificante , Proteínas rab27 de Ligação ao GTP , Humanos , Células CACO-2 , Proliferação de Células/genética , Colite Ulcerativa/genética , Inflamação , Lipopolissacarídeos , MicroRNAs/genética , Proteínas rab27 de Ligação ao GTP/metabolismo , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismoRESUMO
Aortic dissection (AD) develops pathological changes in the separation of the true and false aortic lumen, with high lethality. m6A methylation and oxidative stress have also been shown to be involved in the onset of AD. Through bioinformatics methods, three differentially expressed m6A regulators (YTHDC1, YTHDC2, and RBM15) were excavated from the GSE52093 dataset in the Gene Expression Omnibus (GEO) database, and functional enrichment analysis of the differentially expressed genes (DEGs) regulated by m6A regulators was performed. Then, the genes with oxidative stress-related functions among these genes were found. The protein interaction network of the oxidative stress-related genes and the competing endogenous RNA- (ceRNA-) miRNA-mRNA network were constructed. Among them, DHCR24, P4HB, and PDGFRA, which have m6A differences in AD samples, were selected as key genes. We also performed immune infiltration analysis, as well as cell-gene correlation analysis, on samples from the dataset. The results showed that YTHDC1 was positively correlated with macrophage M1 and negatively correlated with macrophage M2. Finally, we extracted AD and healthy aorta RNA and protein from human tissues that were taken from AD patients and patients who received heart transplants, performed quantitative real-time PCR (qRT-PCR) on YTHDC2 and RBM15, and performed qRT-PCR and western blot (WB) detection on YTHDC1 to verify their differences in AD. The mRNA and protein levels of YTHDC1 were consistent with the results of bioinformatics analysis and were downregulated in AD. Immunofluorescence (IF) was used to colocalize YTHDC1 and endothelial cell marker CD31. After knocking down YTHDC1 in human umbilical vein endothelial cells (HUVECs), reactive oxygen species (ROS) levels had a tendency to increase and the expression of peroxide dismutase SOD2 was decreased. This study provides assistance in discovering the role of m6A regulator YTHDC1 in AD. In particular, m6A modification participates in oxidative stress and jointly affects AD.
Assuntos
Dissecção Aórtica , MicroRNAs , Humanos , Células Endoteliais , Estresse Oxidativo , Adenosina , Fatores de Processamento de RNA , Proteínas do Tecido NervosoRESUMO
Cadmium (Cd) as a ubiquitous toxic heavy metal in the environment, causes severe hazards to human health, such as cellular stress and organ injury. Selenium (Se) was reported to reduce Cd toxicity and the mechanisms have been intensively studied so far. However, it is not yet crystal clear whether the protective effect of Se against Cd-induced cytotoxicity is related to selenoproteins in nerve cells or not. In this study, we found that Cd inhibited selenoprotein thioredoxin reductase 1 (TrxR1; TXNRD1) and decreased the expression level of TrxR1, resulting in cellular oxidative stress, and Se supplements ameliorated Cd-induced cytotoxicity in SH-SY5Y cells. Mechanistically, the detoxification of Se against Cd is attributed to the increase of the cellular TrxR activity and upregulated TrxR1 protein level, culminating in strengthened antioxidant capacity. Results showed that Se supplements attenuated the ROS production and apoptosis in SH-SY5Y cells, and significantly mitigated Cd-induced SH-SY5Y cell death. This study may be a valuable reference for shedding light on the mechanism of Cd-induced cytotoxicity and the role of TrxR1 in Se-mitigated cytotoxicity of Cd in neuroblast cells, which may be helpful for understanding the therapeutic potential of Cd and Se in treating or preventing neurodegenerative diseases, like Alzheimer's disease (AD) and Parkinson's disease (PD).
Assuntos
Neuroblastoma , Selênio , Humanos , Cádmio/toxicidade , Cádmio/metabolismo , Regulação para Baixo , Espécies Reativas de Oxigênio/metabolismo , Ácido Selenioso/metabolismo , Selênio/farmacologia , Selênio/metabolismo , Selenoproteínas/genética , Selenoproteínas/metabolismo , Tiorredoxina Redutase 1/metabolismo , Regulação para CimaRESUMO
In recent years, epigenetic modifications have been increasingly regarded as an important hallmark of cancer. Histone acetylation, as an important part of epigenetic modification, plays a key role in the progress, treatment, and prognosis of many cancers. In this study, based on the TCGA database, we performed LASSO regression and the Cox algorithm to establish a prognostic signature of ovarian cancer associated with histone acetylation modulator genes and verified it externally in the GEO database. Subsequently, we performed an immunological bioinformatics analysis of the model from multiple perspectives using the CIBERSORT algorithm, ESTIMATE algorithm, and TIDE algorithm to verify the accuracy of the model. Based on the prognostic model, we divided ovarian cancer patients into high-risk and low-risk groups, and assessed survival and the efficacy of accepting immunosuppressive therapy. In addition, based on the analysis of characteristics of the model, we also screened targeted drugs for high-risk patients and predicted potential drugs that inhibit platinum resistance through the connectivity map method. We ultimately constructed a histone acetylation modulator-related signature containing 10 histone acetylation modulators, among which HDAC1, HDAC10, and KAT7 can act as independent prognostic factors for ovarian cancer and are related to poor prognosis. In the analysis of the tumor microenvironment, the proportion of the B-infiltrating cells and the macrophages was significantly different between the high- and low-risk groups. Also, the samples with high-risk scores had higher tumor purity and lower immune scores. In terms of treatment, patients in the high-risk group who received immunotherapy had a higher likelihood of immune escape or rejection and were less likely to respond to platinum/paclitaxel therapy. Finally, we screened 20 potential drugs that could target the model for reference.
RESUMO
Deep vein thrombosis (DVT) is a vascular disease. The long non-coding RNA (lncRNA), metastasis-associated lung adenocarcinoma transcript 1 (MALAT1), is positively expressed in DVT tissues, and regulates the biological behavior of endothelial progenitor cells. Here, we explored whether MALAT1 affected the physiology of human vascular endothelial cells (HUVECs) and analyzed its underlying mechanism. To overexpress/silence the expression of MALAT1 in HUVECs, MALAT1-plasmid/MALAT1-small interfering RNA (siRNA) was used. The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide and flow cytometry analyses were performed to observe the cell viability and apoptosis. Reverse transcription-quantitative polymerase chain reaction and western blotting were used to determine the apoptosis-related protein and gene expression levels. We used Starbase software to predict the associations among MALAT1, microRNA (miR)-383-5p, and BCL2-like 11 (BCL2L11). Luciferase reporter assay was used to validate their relationship. Compared to the control vector group, MALAT1-plasmid suppressed the viability and induced apoptosis of HUVECs, while improving Bcl-2-associated X protein (Bax) expression and decreasing Bcl-2 expression. There was an interaction between MALAT1 and miR-383-5p. Compared to the control siRNA group, MALAT1-siRNA increased the cell viability, reduced cell apoptosis, upregulated Bcl-2 expression, and suppressed Bax expression. These changes were reversed by the miR-383-5p inhibitor. Additionally, we verified that BCL2L11 is a target of miR-383-5p. miR-383-5p improved the cell proliferation, while decreasing cell apoptosis in HUVECs by targeting BCL2L11. Therefore, the lncRNA-MALAT1/miR-383-5p/BCL2L11 axis may be effective for DVT treatment.
Assuntos
Proteína 11 Semelhante a Bcl-2 , MicroRNAs , RNA Longo não Codificante , Trombose Venosa , Apoptose/genética , Proteína 11 Semelhante a Bcl-2/genética , Linhagem Celular Tumoral , Células Endoteliais/metabolismo , Humanos , MicroRNAs/genética , RNA Longo não Codificante/genética , RNA Interferente Pequeno , Trombose Venosa/genética , Proteína X Associada a bcl-2RESUMO
Lipid droplets (LDs) are intracellular droplets containing phospholipids and neutral lipids. It is well known that LDs are organelles with a rich proteome. In the nervous system, these droplets may play an important role in maintaining the normal physiological function of nerve cells. Moreover, LDs may relate to the neurodegenerative disorders, such as Alzheimer's disease (AD). However, more information is still needed about the function of LDs. In the study presented here, we identified the protein composition of mouse neuroblastoma (N2a) cell LDs using immunodetection and high-performance liquid chromatography (HPLC) coupled with mass spectrometry (MS). Seventy three LDs proteins were identified. Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses were performed to investigate the potential functions of these proteins. Subsequently, the relationships among the proteins were analyzed by constructing a protein-protein interaction (PPI) network. N2a cell LDs contain multiple Rab GTPases, chaperones, and proteins involved in ubiquitination and transport. Some of these proteins were known to modulate LD formation and were related to the function of nerve cells. This work presents the proteome of N2a cell LDs and will help to identify the role of LDs in the nervous system.
Assuntos
Neuroblastoma , Proteômica , Animais , Gotículas Lipídicas/metabolismo , Metabolismo dos Lipídeos/fisiologia , Camundongos , Proteoma/análise , Proteômica/métodosRESUMO
The protective innate immune response of ß-amyloid peptide (Aß) has been indicated as a risk factor for Alzheimer's disease (AD) due to the rapid amyloidosis. In order to obtain molecular-level insights into the protective and pathogenic roles of Aß, the binding modes between Aß1-42 and the envelop glycoprotein D (gD) of Herpes simplex virus-1 (HSV-1)/Aß1-42 were theoretically investigated by using molecular docking, molecular dynamics (MD) simulations and binding free energy decomposition methods in the present study. The Aß1-42 stably binds to the envelop gD via intermolecular hydrogen bonds and van der Waals (vdW) interactions. The Aß1-42 acquires its equilibrium with higher fluctuation amplitude and a better structured C-terminal in the HSV-1 gD-Aß1-42 complex comparing to that in the Aß1-42-Aß1-42 complex. The amino acid residues of Aß1-42 involved in the formation of the Aß1-42 dimer are fully free and accessible in the HSV-1 gD-Aß1-42 complex. It is favorable for the Aß1-42 monomer to interact with the HSV-1 gD-Aß1-42 complex. It may be responsible for the rapid amyloidosis which entraps the herpesvirus as well as causing AD.
Assuntos
Doença de Alzheimer , Infecções por Herpesviridae , Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/química , Humanos , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Fragmentos de Peptídeos/químicaRESUMO
Physalin B (PB), one of the major active steroidal constituents of Solanaceae Physalis plants, has a wide variety of biological activities. We found that PB significantly down-regulated ß-amyloid (Aß) secretion in N2a/APPsw cells. However, the underlying mechanisms are not well understood. In the current study, we investigated the changes in key enzymes involved in ß-amyloid precursor protein (APP) metabolism and other APP metabolites by treating N2a/APPsw cells with PB at different concentrations. The results indicated that PB reduced Aß secretion, which was caused by down-regulation of ß-secretase (BACE1) expression, as indicated at both the protein and mRNA levels. Further research revealed that PB regulated BACE1 expression by inducing the activation of forkhead box O1 (FoxO1) and inhibiting the phosphorylation of signal transducer and activator of transcription 3 (STAT3). In addition, the effect of PB on BACE1 expression and Aß secretion was reversed by treatment with FoxO1 siRNA and STAT3 antagonist S3I-201. In conclusion, these data demonstrated that PB can effectively down-regulate the expression of BACE1 to reduce Aßsecretion by activating the expression of FoxO1 and inhibiting the phosphorylation of STAT3.
Assuntos
Doença de Alzheimer , Secretases da Proteína Precursora do Amiloide , Secretases da Proteína Precursora do Amiloide/genética , Secretases da Proteína Precursora do Amiloide/metabolismo , Peptídeos beta-Amiloides/metabolismo , Ácido Aspártico Endopeptidases/genética , Ácido Aspártico Endopeptidases/metabolismo , Regulação para Baixo , Proteína Forkhead Box O1/genética , Humanos , Fosforilação , Fator de Transcrição STAT3/genética , Fator de Transcrição STAT3/metabolismo , SecoesteroidesRESUMO
Four new malonylginsenosides, malonylnotoginsenoside Fe (1), malonylnotoginsenoside Ra1 (2), malonylgypenoside LXXV (3), and malonylginsenoside Mc (4), together with two known analogues, malonylfloralginsenoside Rc1 (5) and malonylginsenoside Rc (6), were isolated from the fresh fruits of Panax notoginseng. Their structures were determined by MS and NMR experiments. The anti-proliferative activities of the malonylginsenosides (1-6) against SH-SY5Y human neuroblastoma cell line were evaluated using the MTT assay.
Assuntos
Antineoplásicos Fitogênicos/farmacologia , Ginsenosídeos/farmacologia , Panax notoginseng/química , Antineoplásicos Fitogênicos/isolamento & purificação , Linhagem Celular Tumoral , China , Frutas/química , Ginsenosídeos/isolamento & purificação , Humanos , Estrutura Molecular , Compostos Fitoquímicos/isolamento & purificação , Compostos Fitoquímicos/farmacologiaRESUMO
Forkhead box O1 (FoxO1), a key molecule in the regulation of cell growth, differentiation and metabolism, is an important transcription factor. However, the effect of FoxO1 on Alzheimer's disease (AD) needs further investigation. In this study, we aimed to explore the function and mechanism of FoxO1 in amyloid-ß (Aß) production and tau phosphorylation in AD. First, compared with the age matched wild-type (WT) mice, we showed that FoxO1 protein levels were reduced in the cortices but nearly unchanged in the hippocampi of 6-month-old APPswe/PSEN1dE9 transgenic mice expressing Swedish APP and Presenilin1 delta exon 9 mutations (APP/PS1 mice). Then, we found that overexpression of FoxO1 significantly attenuated Aß production through inhibiting the amyloidogenic processing of ß-amyloid precursor protein (APP), mediated by the key enzymes BACE1 and PS1, in N2a/APPsw cells. Furthermore, in FoxO1-overexpressing HEK293/Tau cells, the decreased levels of tau phosphorylation at selective sites (S262 and T231) were accompanied by increasing the expression of p-GSK-3ß (S9), and reducing p-ERK. In contrast, the total tau (Tau-5), non-phosphorylated tau (Tau-1), p-Tau (S404), CDK5 and PP2A levels remained unchanged. These findings indicate that FoxO1 is related to AD and suggest FoxO1 as a therapeutic target for AD that reduces the levels of both Aß expression and tau phosphorylation.
Assuntos
Peptídeos beta-Amiloides/metabolismo , Proteína Forkhead Box O1/genética , Proteínas tau/metabolismo , Precursor de Proteína beta-Amiloide/genética , Precursor de Proteína beta-Amiloide/metabolismo , Animais , Proteína Forkhead Box O1/metabolismo , Células HEK293 , Humanos , Camundongos , Camundongos Transgênicos , Fosforilação , Presenilina-1/genética , Presenilina-1/metabolismoRESUMO
Hsp90 (Heat shock protein 90) is involved in various processes in cancer occurrence and development, and therefore represents a promising drug target for cancer therapy. In this work, a virtual screening strategy was employed, leading to the identification of a series of compounds bearing a scaffold of 1,3-dibenzyl-2-aryl imidazolidine as novel Hsp90 inhibitors. Compound 4a showed the highest binding affinity to Hsp90α (IC50 = 12 nM) in fluorescence polarization (FP) competition assay and the strongest anti-proliferative activity against human breast adenocarcinoma cell line (MCF-7) and human lung epithelial cell line (A549) with IC50 values of 21.58 µM and 31.22 µM, respectively. Western blotting assays revealed that these novel Hsp90 inhibitors significantly down-regulated the expression level of Her2, a client protein of Hsp90, resulting in the cytotoxicity of these novel Hsp90 inhibitors. The molecular docking study showed that these novel Hsp90 inhibitors bound to the adenosine triphosphate (ATP) binding site at the N-terminus of Hsp90. Furthermore, structure-activity relationship studies indicated that the N-benzyl group is important for the anti-cancer activity of 1,3-dibenzyl-2-aryl imidazolidines.
Assuntos
Proteínas de Choque Térmico HSP90/antagonistas & inibidores , Imidazolidinas/química , Imidazolidinas/farmacologia , Células A549 , Proliferação de Células/efeitos dos fármacos , Ensaios Clínicos como Assunto , Avaliação Pré-Clínica de Medicamentos , Proteínas de Choque Térmico HSP90/metabolismo , Humanos , Concentração Inibidora 50 , Células MCF-7 , Simulação de Acoplamento Molecular , Relação Estrutura-Atividade , Interface Usuário-ComputadorRESUMO
Crizotinib, a drug for anaplastic lymphoma kinase (ALK) positive and c-ros oncogene 1 receptor tyrosine kinase (ROS1) positive non-small cell lung cancer (NSCLC), was structurally optimized via a strategy of structure-based fragment replacing. Computational study showed it was beneficial for interaction of crizotinib and ALK to increase the distance between pyridyl ring and phenyl ring in crizotinib, and thus, a series of novel glycol diaryl ethers were synthesized. The in vitro anti-tumor activity of synthesized compounds was studied in NSCLC cell line H2228 and neurobalstoma cell line SH-SY5Y. Among the synthesized compounds, 9e exhibits stronger anti-cancer activity than crizotinib toward H2228 cell line with an IC50 value of 0.22 µM. Molecular docking indicated that a longer chain between pyridyl ring and phenyl ring enabled molecule to have new interaction with a neighboring small hydrophobic pocket.
Assuntos
Antineoplásicos/química , Crizotinibe/química , Éteres/química , Quinase do Linfoma Anaplásico/antagonistas & inibidores , Quinase do Linfoma Anaplásico/metabolismo , Antineoplásicos/metabolismo , Antineoplásicos/farmacologia , Sítios de Ligação , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Crizotinibe/metabolismo , Crizotinibe/farmacologia , Desenho de Fármacos , Humanos , Simulação de Acoplamento Molecular , Estrutura Terciária de ProteínaRESUMO
The imbalance between ß-amyloid (Aß) generation and clearance plays a fundamental role in the pathogenesis of Alzheimer's disease (AD). The sporadic form of AD is characterized by an overall impairment in Aß clearance. Immunotherapy targeting Aß clearance is believed to be a promising approach and is under active clinical investigation. Autophagy is a conserved pathway for degrading abnormal protein aggregates and is crucial for Aß clearance. We previously reported that oral vaccination with a recombinant AAV/Aß vaccine increased the clearance of Aß from the brain and improved cognitive ability in AD animal models, while the underlying mechanisms were not well understood. In this study, we first demonstrated that oral vaccination with rAAV/Aß decreased the p62 level and up-regulated the LC3B-II/LC3B-I ratio in APP/PS1 mouse brain, suggesting enhanced autophagy. Further, inhibition of the Akt/mTOR pathway may account for autophagy enhancement. We also found increased anti-Aß antibodies in the sera of APP/PS1 mice with oral vaccination, accompanied by elevation of complement factors C1q and C3 levels in the brain. Our results indicate that autophagy is closely involved in oral vaccination-induced Aß clearance, and modulating the autophagy pathway may be an important strategy for AD prevention and intervention.
Assuntos
Doença de Alzheimer/metabolismo , Vacinas contra Alzheimer/administração & dosagem , Peptídeos beta-Amiloides/metabolismo , Autofagia/efeitos dos fármacos , Encéfalo/metabolismo , Fragmentos de Peptídeos/administração & dosagem , Administração Oral , Doença de Alzheimer/prevenção & controle , Peptídeos beta-Amiloides/administração & dosagem , Precursor de Proteína beta-Amiloide/genética , Animais , Encéfalo/efeitos dos fármacos , Dependovirus , Modelos Animais de Doenças , Células HEK293 , Humanos , Masculino , Camundongos , Camundongos Transgênicos , Presenilina-1/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Recombinantes/administração & dosagem , Serina-Treonina Quinases TOR/metabolismoRESUMO
Surgical stress induced depression and anxiety like behavior are common complications among aged individuals suffering from surgery. Recent studies proposed that accumulation of oxidative stress is involved in the etiology of stress induced depression and anxiety. Dapsone possesses antioxidant properties, however, whether dapsone is effective in modulating surgical stress induced brain oxidative damage remains uncertain. The present study aimed to investigate the effect of dapsone on surgical stress induced depressive and anxiety like behavior, and brain oxidative stress in a well-established surgical stress model. Depressive and anxiety like behavior accompanied by elevated brain oxidative stress were observed in aged mice underwent abdominal surgery. Pretreatment with 5 mg/kg dapsone significantly improved the behavioral disorder and ameliorated brain oxidative stress in this model. Further investigation, revealed that surgical stress increased brain NADPH oxidase level, while pretreatment with dapsone abrogated the elevation of NADPH oxidase triggered by surgical stress. These findings suggest that dapsone is effective in improving surgical stress induced brain oxidative damage via down-regulating NADPH oxidase level in aged mice.
Assuntos
Antioxidantes/uso terapêutico , Ansiedade/tratamento farmacológico , Dapsona/uso terapêutico , Depressão/tratamento farmacológico , NADPH Oxidases/metabolismo , Estresse Psicológico/enzimologia , Procedimentos Cirúrgicos Operatórios/efeitos adversos , Envelhecimento/metabolismo , Envelhecimento/psicologia , Animais , Ansiedade/etiologia , Ansiedade/psicologia , Encéfalo/efeitos dos fármacos , Encéfalo/enzimologia , Depressão/etiologia , Depressão/psicologia , Masculino , Camundongos Endogâmicos C57BL , Estresse Oxidativo/efeitos dos fármacos , Estresse Psicológico/complicaçõesRESUMO
Excess manganese (Mn) in brain can be neurotoxic, implicated in several neurodegenerative disorders such as sporadic Alzheimer's disease (AD). However, little is known about the altered metal environment including elevated Mn in the progressive cognitive impairment of AD. Indeed, whether high Mn is associated with AD risk remains elusive. In the study, we recruited 40 Chinese elders with different cognitive statuses and investigated concentrations of Mn in whole blood and plasma amyloid-ß (Aß) peptides. Surprisingly, there were significant correlations of Mn with Mini-Mental State Examination score and Clinical Dementia Rating Scale score. In addition, plasma Aß peptides increased with elevated Mn. Further studies both in vitro and in vivo demonstrated dose-related neurotoxicity and increase of Aß by Mn treatment, which was probably caused by disrupted Aß degradation. These data suggested that high Mn may be involved in the progress of AD as an essential pathogenic factor.
Assuntos
Doença de Alzheimer/complicações , Transtornos Cognitivos/metabolismo , Manganês/efeitos adversos , Manganês/metabolismo , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/induzido quimicamente , Doença de Alzheimer/genética , Precursor de Proteína beta-Amiloide/genética , Animais , Encéfalo/metabolismo , Estudos de Casos e Controles , Linhagem Celular Tumoral , Transtornos Cognitivos/genética , Transtornos Cognitivos/patologia , Comportamento Exploratório/efeitos dos fármacos , Comportamento Exploratório/fisiologia , Líquido Extracelular/efeitos dos fármacos , Líquido Extracelular/metabolismo , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Regulação da Expressão Gênica/genética , Humanos , L-Lactato Desidrogenase/metabolismo , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , Aprendizagem em Labirinto/fisiologia , Entrevista Psiquiátrica Padronizada , Camundongos , Camundongos Transgênicos , Mutação/genética , Neuroblastoma/patologia , Presenilina-1/genéticaRESUMO
Hypoxia-inducible factor (HIF)-1 is the key transcriptional activator mediating both adaptive and pathological responses to hypoxia. The purpose of this study was to find the role of HIF-1 in regulating neprilysin (NEP) at the early stage of hypoxia and explore the underlying mechanism. In this study, we demonstrated that both NEP mRNA and protein levels in neuroblastoma cells were elevated in early stages of hypoxia. Over-expression of HIF-1α gene increased NEP mRNA/protein levels, as well as enzyme activity while knockdown of HIF-1α decreased them. Meanwhile, HIF-1α was shown to bind to histone deacetylase (HDAC)-1 and reduced the association of HDAC-1 with NEP promoter, thus activating NEP gene transcription in a de-repression way. In summary, our results indicated that hypoxia in the early stages would up-regulate NEP expression, in which interaction of HIF-1α and HDAC-1 may play a role. This study suggested that NEP up-regulation might be an adaptive response to hypoxia, which was mediated by HIF-1α binding to HDAC-1 at the early stage of hypoxia.
Assuntos
Histona Desacetilase 1/biossíntese , Subunidade alfa do Fator 1 Induzível por Hipóxia/fisiologia , Neprilisina/biossíntese , Neuroblastoma/metabolismo , Regulação para Cima/fisiologia , Animais , Hipóxia Celular/fisiologia , Feminino , Masculino , Camundongos , Camundongos Endogâmicos ICR , Ligação Proteica/fisiologia , RNA Mensageiro/biossínteseRESUMO
Amyloid-ß (Aß) peptide, which can invoke a cascade of inflammatory responses, is considered to play a causal role in the development and progress of Alzheimer's disease (AD). Xylocoside G (XG) is an active compound isolated from a traditional Chinese medicinal plant, Itoa orientalis. We have previously reported that XG has neuroprotective effects, of which the mechanism is yet unknown. In this study, we investigated the possible mechanisms underlying neuroprotection of XG against Aß-induced toxicity in SH-SY5Y cells and primary neurons. Pretreatment with XG significantly attenuated the cell viability reduction induced by Aß exposure in a dose dependent manner which was testified by 3-[4,5-Dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide (MTT) and lactate dehydrogenase release assay. In addition, pretreatment with XG countered the effect of Aß on Bax and Bcl-2 expression and repressed Aß-induced caspase-3 activation, suggesting that the neuroprotective effect of XG is associated with apoptosis regulation. Neuroinflammation has been implicated in Aß-induced neuronal death. XG significantly attenuated Aß-stimulated release of inflammatory factors such as tumor necrosis factor-α, interleukin-1ß, and prostaglandin E2. It also downregulated the expression of cyclooxygenase-2 in SH-SY5Y cells. Further molecular mechanism studies demonstrated that XG inhibited Aß-induced NF-κB p65 translocation, which was probably the result of inhibition of JNK phosphorylation but not ERK or p38 MAPK pathway by XG. This is the first study to demonstrate that XG protects SH-SY5Y cells against Aß-induced inflammation and apoptosis by down-regulating NF-κB signaling pathways.