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1.
Small ; : e2401713, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38693076

RESUMO

Aqueous zinc-based energy storage devices possess superior safety, cost-effectiveness, and high energy density; however, dendritic growth and side reactions on the zinc electrode curtail their widespread applications. In this study, these issues are mitigated by introducing a polyimide (PI) nanofabric interfacial layer onto the zinc substrate. Simulations reveal that the PI nanofabric promotes a pre-desolvation process, effectively desolvating hydrated zinc ions from Zn(H2O)6 2+ to Zn(H2O)4 2+ before approaching the zinc surface. The exposed zinc ion in Zn(H2O)4 2+ provides an accelerated charge transfer process and reduces the activation energy for zinc deposition from 40 to 21 kJ mol-1. The PI nanofabric also acts as a protective barrier, reducing side reactions at the electrode. As a result, the PI-Zn symmetric cell exhibits remarkable cycling stability over 1200 h, maintaining a dendrite-free morphology and minimal byproduct formation. Moreover, the cell exhibits high stability and low voltage hysteresis even under high current densities (20 mA cm-2, 10 mAh cm-2) thanks to the 3D porous structure of PI nanofabric. When integrated into full cells, the PI-Zn||AC hybrid zinc-ion capacitor and PI-Zn||MnVOH@SWCNT zinc-ion battery achieve impressive lifespans of 15000 and 600 cycles with outstanding capacitance retention. This approach paves a novel avenue for high-performance zinc metal electrodes.

2.
Cancers (Basel) ; 16(8)2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38672694

RESUMO

The Cancers Editorial Office retracts the article, "MicroRNA-21 Plays Multiple Oncometabolic Roles in the Process of NAFLD-Related Hepatocellular Carcinoma via PI3K/AKT, TGF-ß, and STAT3 Signaling" [...].

3.
Cancers (Basel) ; 16(2)2024 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-38254907

RESUMO

Acute leukemia is a particularly problematic collection of hematological cancers, and, while somewhat rare, the survival rate of patients is typically abysmal without bone marrow transplantation. Furthermore, traditional chemotherapies used as standard-of-care for patients cause significant side effects. Understanding the evolution of leukemia to identify novel targets and, therefore, drug treatment regimens is a significant medical need. Genomic rearrangements and other structural variations (SVs) have long been known to be causative and pathogenic in multiple types of cancer, including leukemia. These SVs may be involved in cancer initiation, progression, clonal evolution, and drug resistance, and a better understanding of SVs from individual patients may help guide therapeutic options. Here, we show the utilization of optical genome mapping (OGM) to detect known and novel SVs in the samples of patients with leukemia. Importantly, this technology provides an unprecedented level of granularity and quantitation unavailable to other current techniques and allows for the unbiased detection of novel SVs, which may be relevant to disease pathogenesis and/or drug resistance. Coupled with the chemosensitivities of these samples to FDA-approved oncology drugs, we show how an impartial integrative analysis of these diverse datasets can be used to associate the detected genomic rearrangements with multiple drug sensitivity profiles. Indeed, an insertion in the gene MUSK is shown to be associated with increased sensitivity to the clinically relevant agent Idarubicin, while partial tandem duplication events in the KMT2A gene are related to the efficacy of another frontline treatment, Cytarabine.

4.
J Med Virol ; 95(12): e29325, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-38108211

RESUMO

Hepatitis B virus (HBV) hijacks autophagy for its replication. Nucleos(t)ide analogs (NUCs) treatment suppressed HBV replication and reduced hepatocellular carcinoma (HCC) incidence. However, the use of NUCs in chronic hepatitis B (CHB) patients with normal or minimally elevated serum alanine aminotransferase (ALT) levels is still debated. Animal models are crucial for studying the unanswered issue and evaluating new therapies. MicroRNA-122 (miR-122), which regulates fatty acid and cholesterol metabolism, is downregulated during hepatitis and HCC progression. The reciprocal inhibition of miR-122 with HBV highlights its role in HCC development as a tumor suppressor. By crossbreeding HBV-transgenic mice with miR-122 knockout mice, we generated a hybrid mouse model with a high incidence of HCC up to 89% and normal ALT levels before HCC. The model exhibited early-onset hepatic steatosis, progressive liver fibrosis, and impaired late-phase autophagy. Metabolomics and microarray analysis identified metabolic signatures, including dysregulation of lipid metabolism, inflammation, genomic instability, the Warburg effect, reduced TCA cycle flux, energy deficiency, and impaired free radical scavenging. Antiviral treatment reduced HCC incidence in hybrid mice by approximately 30-35% compared to untreated mice. This effect was linked to the activation of ER stress-responsive transcription factor ATF4, clearance of autophagosome cargo p62, and suppression of the CHOP-mediated apoptosis pathway. In summary, this study suggests that despite minimal ALT elevation, HBV replication can lead to liver injury. Endoplasmic reticulum stress, reduced miR-122 levels, mitochondrial and metabolic dysfunctions, blocking protective autophagy resulting in p62 accumulation, apoptosis, fibrosis, and HCC. Antiviral may improve the above-mentioned pathogenesis through HBV suppression.


Assuntos
Carcinoma Hepatocelular , Hepatite B Crônica , Neoplasias Hepáticas , MicroRNAs , Humanos , Camundongos , Animais , Vírus da Hepatite B , Hepatite B Crônica/complicações , Hepatite B Crônica/tratamento farmacológico , Camundongos Transgênicos , MicroRNAs/genética , MicroRNAs/metabolismo , Replicação Viral , Antivirais/uso terapêutico , Antivirais/farmacologia
5.
ACS Appl Mater Interfaces ; 15(40): 46812-46828, 2023 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-37773582

RESUMO

Manganese oxide is an effective active material in several electrochemical systems, including batteries, supercapacitors, and electrochemical deionization (ECDI). This work conducts a comprehensive study on the ion-selective behavior of MnOx to fulfill the emptiness in the energy and environmental science field. Furthermore, it broadens the promising application of MnOx in the ion-selective ECDI system. We propose a time-dependent multimechanism ion-selective behavior with the following guidelines by utilizing a microfluidic cell and the electrochemical quartz crystal microbalance (EQCM) analysis. (1) Hydrated radius is the most critical factor for ions with the same valence, and MnOx tends to capture cations with a small hydrated radius. (2) The importance of charge density rises when comparing cations with different valences, and MnOx prefers to capture divalent cations with a strong electrostatic attraction at prolonged times. Under this circumstance, ion swapping may occur where divalent cations replace monovalent cations. (3) NH4+ triggers MnOx dissolution, leading to performance and stability decay. The EQCM evidence has directly verified the proposed mechanisms, and these data provide a novel but simple method to judge ion selectivity preference. The overall ion selectivity sequence is Ca2+ > Mg2+ > K+ > NH4+> Na+ > Li+ with the highest selectivity values of ßCa//Li and ßCa//Na around 3 at the deionization time = 10 min.

6.
Elife ; 112022 05 23.
Artigo em Inglês | MEDLINE | ID: mdl-35604009

RESUMO

Two epigenetic pathways of transcriptional repression, DNA methylation and polycomb repressive complex 2 (PRC2), are known to regulate neuronal development and function. However, their respective contributions to brain maturation are unknown. We found that conditional loss of the de novo DNA methyltransferase Dnmt3a in mouse excitatory neurons altered expression of synapse-related genes, stunted synapse maturation, and impaired working memory and social interest. At the genomic level, loss of Dnmt3a abolished postnatal accumulation of CG and non-CG DNA methylation, leaving adult neurons with an unmethylated, fetal-like epigenomic pattern at ~222,000 genomic regions. The PRC2-associated histone modification, H3K27me3, increased at many of these sites. Our data support a dynamic interaction between two fundamental modes of epigenetic repression during postnatal maturation of excitatory neurons, which together confer robustness on neuronal regulation.


Assuntos
DNA Metiltransferase 3A , Código das Histonas , Neurônios , Sinapses , Animais , Encéfalo/crescimento & desenvolvimento , Encéfalo/metabolismo , Encéfalo/fisiopatologia , DNA Metiltransferase 3A/genética , DNA Metiltransferase 3A/metabolismo , Modelos Animais de Doenças , Código das Histonas/genética , Código das Histonas/fisiologia , Histonas/genética , Histonas/metabolismo , Camundongos , Camundongos Knockout , Neurônios/metabolismo , Neurônios/fisiologia , Complexo Repressor Polycomb 2/genética , Complexo Repressor Polycomb 2/metabolismo , Sinapses/metabolismo , Sinapses/fisiologia
8.
iScience ; 25(2): 103760, 2022 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-35036860

RESUMO

Impressive global efforts have identified both rare and common gene variants associated with severe COVID-19 using sequencing technologies. However, these studies lack the sensitivity to accurately detect several classes of variants, especially large structural variants (SVs), which account for a substantial proportion of genetic diversity including clinically relevant variation. We performed optical genome mapping on 52 severely ill COVID-19 patients to identify rare/unique SVs as decisive predisposition factors associated with COVID-19. We identified 7 SVs involving genes implicated in two key host-viral interaction pathways: innate immunity and inflammatory response, and viral replication and spread in nine patients, of which SVs in STK26 and DPP4 genes are the most intriguing candidates. This study is the first to systematically assess the potential role of SVs in the pathogenesis of COVID-19 severity and highlights the need to evaluate SVs along with sequencing variants to comprehensively associate genomic information with interindividual variability in COVID-19 phenotypes.

9.
Cells ; 10(12)2021 12 06.
Artigo em Inglês | MEDLINE | ID: mdl-34943942

RESUMO

Obesity is closely linked to metabolic diseases, particularly non-alcoholic steatohepatitis (NASH) or non-alcoholic fatty liver disease (NAFLD), ultimately leading to hepatocellular carcinoma (HCC). However, the molecular mechanisms of NASH-associated HCC (NAHCC) remain elusive. To explore the impact of Max dimerization protein 3 (MXD3), a transcription factor that regulates several cellular functions in disorders associated with metabolic diseases, we conditionally expressed Mxd3 proteins using Tet-on mxd3 transgenic zebrafish (MXs) with doxycycline (MXs + Dox) or without doxycycline (MXs - Dox) treatment. Overexpression of global MXD3 (gMX) or hepatic Mxd3 (hMX) was associated with obesity-related NAFLD pathophysiology in gMX + Dox, and liver fibrosis and HCC in hMX + Dox. Oil Red O (ORO)-stained signals were seen in intravascular blood vessels and liver buds of larval gMX + Dox, indicating that Mxd3 functionally promotes lipogenesis. The gMX + Dox-treated young adults exhibited an increase in body weight and visceral fat accumulation. The hMX + Dox-treated young adults showed normal body characteristics but exhibited liver steatosis and NASH-like phenotypes. Subsequently, steatohepatitis, liver fibrosis, and NAHCC were found in 6-month-old gMX + Dox adults compared with gMX - Dox adults at the same stage. Overexpression of Mxd3 also enhanced AR expression accompanied by the increase of AR-signaling pathways resulting in hepatocarcinogenesis in males. Our results demonstrate that global actions of Mxd3 are central to the initiation of obesity in the gMX zebrafish through their effects on adipogenesis and that MXD3 could serve as a therapeutic target for obesity-associated liver diseases.


Assuntos
Carcinoma Hepatocelular/genética , Neoplasias Hepáticas/genética , Obesidade/genética , Receptores Androgênicos/genética , Proteínas Repressoras/genética , Adipogenia/genética , Animais , Animais Geneticamente Modificados/genética , Carcinoma Hepatocelular/complicações , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/patologia , Doxiciclina/farmacologia , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Lipogênese/efeitos dos fármacos , Fígado/metabolismo , Neoplasias Hepáticas/complicações , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/patologia , Hepatopatia Gordurosa não Alcoólica/complicações , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Hepatopatia Gordurosa não Alcoólica/genética , Hepatopatia Gordurosa não Alcoólica/patologia , Obesidade/complicações , Obesidade/tratamento farmacológico , Obesidade/patologia , Transdução de Sinais/genética , Peixe-Zebra/genética
10.
Cancers (Basel) ; 13(21)2021 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-34771727

RESUMO

Colorectal cancer (CRC) is a leading cause of cancer-related mortality worldwide. Patients with inflammatory bowel disease (IBD) have a high risk of developing CRC. Inflammatory cytokines are regulated by complex gene networks and regulatory RNAs, especially microRNAs. MicroRNA-21 (miR-21) is amongst the most frequently upregulated microRNAs in inflammatory responses and cancer development. miR-21 has become a target for genetic and pharmacological regulation in various diseases. However, the association between inflammation and tumorigenesis in the gut is largely unknown. Hence, in this study, we generated a zebrafish model (ImiR-21) with inducible overexpression of miR-21 in the intestine. The results demonstrate that miR-21 can induce CRC or colitis-associated cancer (CAC) in ImiR-21 through the PI3K/AKT, PDCD4/TNF-α, and IL-6/STAT3 signaling network. miR-21 activated the PI3K/AKT and NF-κB signaling pathways, leading to initial inflammation; thereafter, miR-21 and TNF-α repressed PDCD4 and its tumor suppression activity. Eventually, active STAT3 stimulated a strong inflammatory response and activated the invasion/metastasis process of tumor cells. Hence, our findings indicate that miR-21 is critical for the development of CRC/CAC via the PI3K/AKT, STAT3, and PDCD4/TNF-α signaling networks.

11.
Biomedicines ; 9(8)2021 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-34440144

RESUMO

The functions of anorexigenic neurons secreting proopiomelanocortin (POMC)/alpha-melanocyte-stimulating hormone (α-MSH) of the melanocortin system in the hypothalamus in vertebrates are energy homeostasis, food intake, and body weight regulation. However, the mechanisms remain elusive. This article reports on zebrafish that have been genetically engineered to produce α-MSH mutants, α-MSH-7aa and α-MSH-8aa, selectively lacking 7 and 8 amino acids within the α-MSH region, but retaining most of the other normal melanocortin-signaling (Pomc-derived) peptides. The α-MSH mutants exhibited hyperphagic phenotypes leading to body weight gain, as observed in human patients and mammalian models. The actions of several genes regulating appetite in zebrafish are similar to those in mammals when analyzed using gene expression analysis. These include four selected orexigenic genes: Promelanin-concentrating hormone (pmch), agouti-related protein 2 (agrp2), neuropeptide Y (npy), and hypothalamic hypocretin/orexin (hcrt). We also study five selected anorexigenic genes: Brain-derived neurotrophic factor (bdnf), single-minded homolog 1-a (sim1a), corticotropin-releasing hormone b (crhb), thyrotropin-releasing hormone (trh), and prohormone convertase 2 (pcsk2). The orexigenic actions of α-MSH mutants are rescued completely after hindbrain ventricle injection with a synthetic analog of α-MSH and a melanocortin receptor agonist, Melanotan II. We evaluate the adverse effects of MSH depletion on energy balance using the Alamar Blue metabolic rate assay. Our results show that α-MSH is a key regulator of POMC signaling in appetite regulation and energy expenditure, suggesting that it might be a potential therapeutic target for treating human obesity.

12.
Cancers (Basel) ; 13(5)2021 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-33668153

RESUMO

MicroRNA-21 (miR-21) is one of the most frequently upregulated miRNAs in liver diseases such as nonalcoholic fatty liver disease (NAFLD) and hepatocellular carcinoma (HCC). However, mechanistic pathways that connect NAFLD and HCC remain elusive. We developed a doxycycline (Dox)-inducible transgenic zebrafish model (LmiR21) which exhibited an upregulation of miR-21 in the liver, which in turn induced the full spectrum of NAFLD, including steatosis, inflammation, fibrosis, and HCC, in the LmiR21 fish. Diethylnitrosamine (DEN) treatment led to accelerated liver tumor formation and exacerbated their aggressiveness. Moreover, prolonged miR-21 expression for up to ten months induced nonalcoholic steatohepatitis (NASH)-related HCC (NAHCC). Immunoblotting and immunostaining confirmed the presence of miR-21 regulatory proteins (i.e., PTEN, SMAD7, p-AKT, p-SMAD3, and p-STAT3) in human nonviral HCC tissues and LmiR21 models. Thus, we demonstrated that miR-21 can induce NAHCC via at least three mechanisms: First, the occurrence of hepatic steatosis increases with the decrease of ptenb, pparaa, and activation of the PI3K/AKT pathway; second, miR-21 induces hepatic inflammation (or NASH) through an increase in inflammatory gene expression via STAT3 signaling pathways, and induces liver fibrosis through hepatic stellate cell (HSC) activation and collagen deposition via TGF-ß/Smad3/Smad7 signaling pathways; finally, oncogenic activation of Smad3/Stat3 signaling pathways induces HCC. Our LmiR21 models showed similar molecular pathology to the human cancer samples in terms of initiation of lipid metabolism disorder, inflammation, fibrosis and activation of the PI3K/AKT, TGF-ß/SMADs and STAT3 (PTS) oncogenic signaling pathways. Our findings indicate that miR-21 plays critical roles in the mechanistic perspectives of NAHCC development via the PTS signaling networks.

13.
J Pers Med ; 11(2)2021 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-33670576

RESUMO

Genomic structural variants comprise a significant fraction of somatic mutations driving cancer onset and progression. However, such variants are not readily revealed by standard next-generation sequencing. Optical genome mapping (OGM) surpasses short-read sequencing in detecting large (>500 bp) and complex structural variants (SVs) but requires isolation of ultra-high-molecular-weight DNA from the tissue of interest. We have successfully applied a protocol involving a paramagnetic nanobind disc to a wide range of solid tumors. Using as little as 6.5 mg of input tumor tissue, we show successful extraction of high-molecular-weight genomic DNA that provides a high genomic map rate and effective coverage by optical mapping. We demonstrate the system's utility in identifying somatic SVs affecting functional and cancer-related genes for each sample. Duplicate/triplicate analysis of select samples shows intra-sample reliability but also intra-sample heterogeneity. We also demonstrate that simply filtering SVs based on a GRCh38 human control database provides high positive and negative predictive values for true somatic variants. Our results indicate that the solid tissue DNA extraction protocol, OGM and SV analysis can be applied to a wide variety of solid tumors to capture SVs across the entire genome with functional importance in cancer prognosis and treatment.

14.
Proc Natl Acad Sci U S A ; 117(49): 31410-31416, 2020 12 08.
Artigo em Inglês | MEDLINE | ID: mdl-33229517

RESUMO

Next-generation sequencing technologies allowed sequencing of thousands of genomes. However, there are genomic regions that remain difficult to characterize, including telomeres, centromeres, and other low-complexity regions, as well as transposable elements and endogenous viruses. Human herpesvirus 6A and 6B (HHV-6A and HHV-6B) are closely related viruses that infect most humans and can integrate their genomes into the telomeres of infected cells. Integration also occurs in germ cells, meaning that the virus can be inherited and result in individuals harboring the virus in every cell of their body. The integrated virus can reactivate and cause disease in humans. While it is well established that the virus resides in the telomere region, the integration locus is poorly defined due to the low sequence complexity (TTAGGG)n of telomeres that cannot be easily resolved through sequencing. We therefore employed genome imaging of the integrated HHV-6A and HHV-6B genomes using whole-genome optical site mapping technology. Using this technology, we identified which chromosome arm harbors the virus genome and obtained a high-resolution map of the integration loci of multiple patients. Surprisingly, this revealed long telomere sequences at the virus-subtelomere junction that were previously missed using PCR-based approaches. Contrary to what was previously thought, our technique revealed that the telomere lengths of chromosomes harboring the integrated virus genome were comparable to the other chromosomes. Taken together, our data shed light on the genetic structure of the HHV-6A and HHV-6B integration locus, demonstrating the utility of optical mapping for the analysis of genomic regions that are difficult to sequence.


Assuntos
Herpesvirus Humano 6/fisiologia , Imagem Óptica , Telômero/metabolismo , Cromossomos Humanos/genética , Genoma Viral , Herpesvirus Humano 6/genética , Interações Hospedeiro-Patógeno , Humanos , Homeostase do Telômero
15.
Neurobiol Dis ; 125: 211-218, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30716470

RESUMO

BACKGROUND: Epidemiological studies suggest that the risk of neurodevelopmental disorders such as autism spectrum disorder (ASD) and schizophrenia is increased by prenatal exposure to viral or bacterial infection during pregnancy. It is still unclear how activation of the maternal immune response interacts with underlying genetic factors to influence observed ASD phenotypes. METHODS: The current study investigated how maternal immune activation (MIA) in mice impacts gene expression in the frontal cortex in adulthood, and how these molecular changes relate to deficits in cognitive flexibility and social behavior, and increases in repetitive behavior that are prevalent in ASD. Poly(I:C) (20 mg/kg) was administered to dams on E12.5 and offspring were tested for social approach behavior, repetitive grooming, and probabilistic reversal learning in adulthood (n = 8 vehicle; n = 9 Poly(I:C)). We employed next-generation high-throughput mRNA sequencing (RNA-seq) to comprehensively investigate the transcriptome profile in frontal cortex of adult offspring of Poly(I:C)-exposed dams. RESULTS: Exposure to poly(I:C) during gestation impaired probabilistic reversal learning and decreased social approach in MIA offspring compared to controls. We found long-term effects of MIA on expression of 24 genes, including genes involved in glutamatergic neurotransmission, mTOR signaling and potassium ion channel activity. Correlations between gene expression and specific behavioral measures provided insight into genes that may be responsible for ASD-like behavioral alterations. CONCLUSIONS: These findings suggest that MIA can lead to impairments in cognitive flexibility in mice similar to those exhibited in ASD individuals, and that these impairments are associated with altered gene expression in frontal cortex.


Assuntos
Lobo Frontal/imunologia , Transtornos do Neurodesenvolvimento/imunologia , Complicações Infecciosas na Gravidez/imunologia , Efeitos Tardios da Exposição Pré-Natal/imunologia , Transcrição Gênica/imunologia , Animais , Comportamento Animal/fisiologia , Cognição/fisiologia , Feminino , Lobo Frontal/fisiopatologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Gravidez , Comportamento Social
16.
Biochim Biophys Acta Mol Cell Biol Lipids ; 1863(8): 844-856, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29678641

RESUMO

Nonalcoholic fatty liver disease (NAFLD) has been associated with the function and changes in expression levels of microRNAs (miRs). MiR-7 has been proven to play an important role in many cellular processes; however, its functions in the context of liver lipogenesis remain unknown. We applied the microRNA-sponge (miR-SP) technology and generated transgenic miR-7a-SP models (hC7aSP and bC7aSP), which disrupted the activities of hepatic miR-7a and induced the early onset of NAFLD and nonalcoholic steatohepatitis (NASH) in zebrafish. We identified a novel miR-7a target, YY1, and demonstrated novel miR-7a functions to regulate zebrafish hepatic lipid metabolism by controlling YY1 stabilization through the regulation of the expression of lipogenic signaling pathways. Correspondingly, liver specific miR-7a depletion functionally promoted lipid accumulation in hC7ASP livers. NASH hC7aSP increased the expression of inflammatory genes (il-1b, il-6, tnf-α, ifn-γ, nfkb2, and NF-kB) and endoplasmic reticulum stress markers (atf6, ern2, ire1, perk, hspa5 and ddit3). Molecular analysis revealed that miR-7a-SP can stabilize YY1 expression and contribute to the accumulation of hepatic triglycerides by reducing the CHOP-10 expression in the hC7aSP and then inducing the transactivation of C/EBP-α and PPAR-γ expression. PPAR-γ antagonists and miR-7a mimic treatment ameliorate hC7aSP NASH phenotypes. CONCLUSION: Our results suggest that miR-7a-SP acts as a lipid enhancer by directly increasing YY1 stability to disrupt CHOP-10-dependent suppression of lipogenic pathways, resulting in increased lipid accumulation. MiR-7a expression improves liver steatosis and steatohepatitis in hC7aSPs, which suggests a novel strategy for the prevention and early treatment of NASH in humans.


Assuntos
Vias Biossintéticas/genética , Modelos Animais de Doenças , Lipogênese/genética , MicroRNAs/metabolismo , Hepatopatia Gordurosa não Alcoólica/genética , Fator de Transcrição YY1/genética , Proteínas de Peixe-Zebra/genética , Peixe-Zebra , Animais , Animais Geneticamente Modificados , Linhagem Celular , Chaperona BiP do Retículo Endoplasmático , Feminino , Humanos , Fígado/metabolismo , Fígado/patologia , Masculino , MicroRNAs/antagonistas & inibidores , MicroRNAs/genética , Hepatopatia Gordurosa não Alcoólica/patologia , Oncorhynchus mykiss , PPAR gama/antagonistas & inibidores , PPAR gama/metabolismo , Estabilidade Proteica , Fator de Transcrição CHOP/metabolismo , Fator de Transcrição YY1/metabolismo , Proteínas de Peixe-Zebra/metabolismo
17.
Int J Mol Sci ; 19(1)2017 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-29286302

RESUMO

miR-27b has emerged as a regulatory hub in cholesterol and lipid metabolism, and as a potential therapeutic target for treating atherosclerosis and obesity. However, the impact of miR-27b on lipid levels in vivo remains to be determined. Zebrafish lipids are normally stored as triacylglycerols (TGs) and their main storage sites are visceral, intramuscular, and subcutaneous lipid depots, and not blood vessels and liver. In this study, we applied microRNA-sponge (miR-SP) technology and generated zebrafish expressing transgenic miR-27b-SP (C27bSPs), which disrupted endogenous miR-27b activity and induced intravascular lipid accumulation (hyperlipidemia) and the early onset of nonalcoholic fatty liver disease (NAFLD) and nonalcoholic steatohepatitis (NASH). Oil Red O staining predominantly increased in the blood vessels and livers of larvae and juvenile C27bSPs, indicating that miR-27b depletion functionally promoted lipid accumulation. C27bSPs also showed an increased weight gain with larger fat pads, resulting from adipocyte hyperplasia. Molecular analysis revealed that miR-27b depletion increased the expression of genes that are associated with lipogenesis and the endoplasmic reticulum (ER). Moreover, miR-27b-SP increased peroxisome proliferator-activated receptor γ (PPAR-γ), CCAAT enhancer binding protein-α (C/EBP-α, and sterol regulatory element binding transcription factor 1c (SREBP-1c) expression and contributed to lipogenesis and adipogenesis. CONCLUSION: Our results suggest that miR-27b-SP acts as a lipid enhancer by directly increasing the expression of several lipogenic/adipogenic transcriptional factors, resulting in increased lipogenesis and adipogenesis. In this study, miR-27b expression improved lipid metabolism in C27bSPs, which suggests that miR-27b is an important lipogenic factor in regulating early onset of hyperlipidemia and adipogenesis in zebrafish.


Assuntos
Adipogenia/genética , Hiperlipidemias/genética , Hiperplasia/genética , Larva/genética , MicroRNAs/genética , Hepatopatia Gordurosa não Alcoólica/genética , Adipócitos/metabolismo , Adipócitos/patologia , Animais , Animais Geneticamente Modificados , Antagomirs/genética , Antagomirs/metabolismo , Sequência de Bases , Proteínas Estimuladoras de Ligação a CCAAT/genética , Proteínas Estimuladoras de Ligação a CCAAT/metabolismo , Modelos Animais de Doenças , Embrião não Mamífero , Regulação da Expressão Gênica no Desenvolvimento , Genes Reporter , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Hiperlipidemias/metabolismo , Hiperlipidemias/patologia , Hiperplasia/metabolismo , Hiperplasia/patologia , Larva/crescimento & desenvolvimento , Larva/metabolismo , Metabolismo dos Lipídeos/genética , Proteínas Luminescentes/genética , Proteínas Luminescentes/metabolismo , MicroRNAs/antagonistas & inibidores , MicroRNAs/metabolismo , Hepatopatia Gordurosa não Alcoólica/metabolismo , Hepatopatia Gordurosa não Alcoólica/patologia , PPAR gama/genética , PPAR gama/metabolismo , Transdução de Sinais , Proteína de Ligação a Elemento Regulador de Esterol 1/genética , Proteína de Ligação a Elemento Regulador de Esterol 1/metabolismo , Peixe-Zebra , Proteína Vermelha Fluorescente
18.
Sci Rep ; 7(1): 16362, 2017 11 27.
Artigo em Inglês | MEDLINE | ID: mdl-29180630

RESUMO

Activating transcription factor 4 (ATF4) is constitutively expressed in a variety of tissues, and regulates several pathological features associated with metabolic diseases such as non-alcoholic fatty liver diseases (NAFLD) and obesity. However, the role of ATF4 in animal model systems is poorly understood. To investigate ATF4 functions in zebrafish, we conditionally expressed ATF4 proteins, using a Tet-off transgenic system. We observed early-onset hyperlipidaemia and liver steatosis in ATF4 transgenic zebrafish (ATs) without doxycycline treatment (ATs - Dox). Oil Red O (ORO)-stained signals were predominant in the intravascular blood vessels and liver buds of larval ATs - Dox, indicating that ATF4 functionally promotes lipogenesis. Further, ATF4 overexpression accompanied the stimulation of the unfolded protein response. Therefore, adult ATs - Dox showed increased lipid accumulation, which led, in turn, to liver steatosis. Liver histology and ORO staining of ATs - Dox hepatocytes also indicated oxidative stress and induced NASH-like phenotypes. Moreover, ATF4 overexpression accelerated adipocyte differentiation via CCAAT enhancer binding protein-beta and peroxisome proliferator activated receptor-gamma inducible expression. ATs-Dox zebrafish showed increased weight gain with larger fat pads due to adipocyte hyperplasia. In this study, we report that ATF4 is a potential stimulator of lipid biosynthesis and adipogenesis in zebrafish.


Assuntos
Fator 4 Ativador da Transcrição/genética , Adipogenia/genética , Hiperlipidemias/genética , Hiperlipidemias/metabolismo , Hepatopatia Gordurosa não Alcoólica/genética , Hepatopatia Gordurosa não Alcoólica/metabolismo , Peixe-Zebra/genética , Peixe-Zebra/metabolismo , Fator 4 Ativador da Transcrição/metabolismo , Animais , Animais Geneticamente Modificados , Modelos Animais de Doenças , Feminino , Expressão Gênica , Metabolismo dos Lipídeos , Masculino , Hepatopatia Gordurosa não Alcoólica/patologia , Estresse Oxidativo , Fenótipo
19.
World J Psychiatry ; 6(1): 102-17, 2016 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-27014601

RESUMO

Identifying biomarkers that can be used as diagnostics or predictors of treatment response (theranostics) in people with schizophrenia (Sz) will be an important step towards being able to provide personalized treatment. Findings from the studies in brain tissue have not yet been translated into biomarkers that are practical in clinical use because brain biopsies are not acceptable and neuroimaging techniques are expensive and the results are inconclusive. Thus, in recent years, there has been search for blood-based biomarkers for Sz as a valid alternative. Although there are some encouraging preliminary data to support the notion of peripheral biomarkers for Sz, it must be acknowledged that Sz is a complex and heterogeneous disorder which needs to be further dissected into subtype using biological based and clinical markers. The scope of this review is to critically examine published blood-based biomarker of Sz, focusing on possible uses for diagnosis, treatment response, or their relationship with schizophrenia-associated phenotype. We sorted the studies into six categories which include: (1) brain-derived neurotrophic factor; (2) inflammation and immune function; (3) neurochemistry; (4) oxidative stress response and metabolism; (5) epigenetics and microRNA; and (6) transcriptome and proteome studies. This review also summarized the molecules which have been conclusively reported as potential blood-based biomarkers for Sz in different blood cell types. Finally, we further discusses the pitfall of current blood-based studies and suggest that a prediction model-based, Sz specific, blood oriented study design as well as standardize blood collection conditions would be useful for Sz biomarker development.

20.
Schizophr Res ; 169(1-3): 83-88, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26545297

RESUMO

BACKGROUND/OBJECTIVES: Having separated a sub-group of people with schizophrenia based on a marked loss of cortical [(3)H]pirenzepine binding (MRDS); we wished to determine if MRDS had lower levels of [(3)H]pirenzepine and other muscarinic receptor antagonist binding to the striatum and if this was due to loss of pre- or post-synaptic neurons or glia measured using surrogate markers (25 kilodalton synaptosomal-associated protein (SNAP 25), postsynaptic density protein 95 (PSD 95), glial fibrillary acidic protein (GFAP) 41/43) of cell number. METHODS: [(3)H]pirenzepine, [(3)H]AF-DX 384 and [(3)H]4-DAMP binding to the striatum from 37 subjects with schizophrenia (19 MRDS) and 20 controls as well as SNAP 25, PSD 95 and GFAP 41/43 in crude particulate membrane were measured. RESULTS: [(3)H]pirenzepine and [(3)H]AF-DX 384 binding to the striatum were significantly lower in schizophrenia due to lower binding of both radioligands in the striatum from MRDS. Levels of PSD 95 were higher in schizophrenia, predominantly due to higher levels in MRDS. CONCLUSIONS: Our data suggest muscarinic M1 ([(3)H]pirenzepine) and M2 and/or M4 receptors ([(3)H]AF-DX 384) are lower in the striatum from MRDS which could mediate inappropriate adaption to internal and external cues which, in turn, would affect motivation, cognition and motor control. Increased levels of PSD 95 could indicate increased post-synaptic boutons or changes in NMDA receptor-mediated signalling in MRDS.


Assuntos
Corpo Estriado/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Proteínas de Membrana/metabolismo , Neuroglia/metabolismo , Neurônios/metabolismo , Receptores Muscarínicos/metabolismo , Esquizofrenia/metabolismo , Autorradiografia , Western Blotting , Corpo Estriado/patologia , Proteína 4 Homóloga a Disks-Large , Feminino , Proteína Glial Fibrilar Ácida/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Antagonistas Muscarínicos , Neuroglia/patologia , Neurônios/patologia , Piperidinas , Pirenzepina/análogos & derivados , Ensaio Radioligante , Compostos Radiofarmacêuticos , Esquizofrenia/patologia , Proteína 25 Associada a Sinaptossoma/metabolismo , Trítio
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