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1.
Bioorg Chem ; 150: 107514, 2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38870704

RESUMO

Alzheimer's disease (AD), a progressive neurodegenerative disorder, has garnered increased attention due to its substantial economic burden and the escalating global aging phenomenon. Amyloid-ß deposition is a key pathogenic marker observed in the brains of Alzheimer's sufferers. Based on real-time, safe, low-cost, and commonly used, near-infrared fluorescence (NIRF) imaging technology have become an essential technique for the detection of AD in recent years. In this work, NIRF probes with hemicyanine structure were designed, synthesized and evaluated for imaging Aß aggregates in the brain. We use the hemicyanine structure as the parent nucleus to enhance the probe's optical properties. The introduction of PEG chain is to improve the probe's brain dynamice properties, and the alkyl chain on the N atom is to enhance the fluorescence intensity of the probe after binding to the Aß aggregates as much as possible. Among these probes, Z2, Z3, Z6, X3, X6 and T1 showed excellent optical properties and high affinity to Aß aggregates (Kd = 24.31 âˆ¼ 59.60 nM). In vitro brain section staining and in vivo NIRF imaging demonstrated that X6 exhibited superior discrimination between Tg mice and WT mice, and X6 has the best brain clearance rate. As a result, X6 was identified as the optimal probe. Furthermore, the docking theory calculation results aided in describing X6's binding behavior with Aß aggregates. As a high-affinity, high-selectivity, safe and effective probe of targeting Aß aggregates, X6 is a promising NIRF probe for in vivo detection of Aß aggregates in the AD brain.

2.
Cell ; 2024 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-38936359

RESUMO

Duplication is a foundation of molecular evolution and a driver of genomic and complex diseases. Here, we develop a genome editing tool named Amplification Editing (AE) that enables programmable DNA duplication with precision at chromosomal scale. AE can duplicate human genomes ranging from 20 bp to 100 Mb, a size comparable to human chromosomes. AE exhibits activity across various cell types, encompassing diploid, haploid, and primary cells. AE exhibited up to 73.0% efficiency for 1 Mb and 3.4% for 100 Mb duplications, respectively. Whole-genome sequencing and deep sequencing of the junctions of edited sequences confirm the precision of duplication. AE can create chromosomal microduplications within disease-relevant regions in embryonic stem cells, indicating its potential for generating cellular and animal models. AE is a precise and efficient tool for chromosomal engineering and DNA duplication, broadening the landscape of precision genome editing from an individual genetic locus to the chromosomal scale.

3.
Pharmacol Rev ; 76(3): 414-453, 2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38697854

RESUMO

Since its discovery over 35 years ago, MDM2 has emerged as an attractive target for the development of cancer therapy. MDM2's activities extend from carcinogenesis to immunity to the response to various cancer therapies. Since the report of the first MDM2 inhibitor more than 30 years ago, various approaches to inhibit MDM2 have been attempted, with hundreds of small-molecule inhibitors evaluated in preclinical studies and numerous molecules tested in clinical trials. Although many MDM2 inhibitors and degraders have been evaluated in clinical trials, there is currently no Food and Drug Administration (FDA)-approved MDM2 inhibitor on the market. Nevertheless, there are several current clinical trials of promising agents that may overcome the past failures, including agents granted FDA orphan drug or fast-track status. We herein summarize the research efforts to discover and develop MDM2 inhibitors, focusing on those that induce MDM2 degradation and exert anticancer activity, regardless of the p53 status of the cancer. We also describe how preclinical and clinical investigations have moved toward combining MDM2 inhibitors with other agents, including immune checkpoint inhibitors. Finally, we discuss the current challenges and future directions to accelerate the clinical application of MDM2 inhibitors. In conclusion, targeting MDM2 remains a promising treatment approach, and targeting MDM2 for protein degradation represents a novel strategy to downregulate MDM2 without the side effects of the existing agents blocking p53-MDM2 binding. Additional preclinical and clinical investigations are needed to finally realize the full potential of MDM2 inhibition in treating cancer and other chronic diseases where MDM2 has been implicated. SIGNIFICANCE STATEMENT: Overexpression/amplification of the MDM2 oncogene has been detected in various human cancers and is associated with disease progression, treatment resistance, and poor patient outcomes. This article reviews the previous, current, and emerging MDM2-targeted therapies and summarizes the preclinical and clinical studies combining MDM2 inhibitors with chemotherapy and immunotherapy regimens. The findings of these contemporary studies may lead to safer and more effective treatments for patients with cancers overexpressing MDM2.


Assuntos
Antineoplásicos , Neoplasias , Proteínas Proto-Oncogênicas c-mdm2 , Humanos , Proteínas Proto-Oncogênicas c-mdm2/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-mdm2/metabolismo , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Animais , Antineoplásicos/uso terapêutico , Antineoplásicos/farmacologia , Terapia de Alvo Molecular
4.
Pathol Res Pract ; 259: 155371, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38820929

RESUMO

BACKGROUND: Targeted therapy with combined dabrafenib and trametinib has been proven to provide clinical benefits in patients with BRAF V600E mutation-positive NSCLC. Nevertheless, the treatment strategy for NSCLC patients with BRAF non-V600E mutations remains limited. CASE PRESENTATION: Here, we present a NSCLC patient with a BRAF N581S mutation, which is a class III BRAF mutation, and this patient had a durable response to targeted therapy with combined anlotinib and tislelizumab. CONCLUSION: We hope to bring more attention to rare non-V600 BRAF mutations by presenting this case of NSCLC.


Assuntos
Adenocarcinoma de Pulmão , Anticorpos Monoclonais Humanizados , Protocolos de Quimioterapia Combinada Antineoplásica , Indóis , Neoplasias Pulmonares , Proteínas Proto-Oncogênicas B-raf , Quinolinas , Humanos , Adenocarcinoma de Pulmão/tratamento farmacológico , Adenocarcinoma de Pulmão/genética , Adenocarcinoma de Pulmão/patologia , Anticorpos Monoclonais Humanizados/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Indóis/uso terapêutico , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Mutação , Proteínas Proto-Oncogênicas B-raf/genética , Quinolinas/uso terapêutico , Resultado do Tratamento
5.
J Med Chem ; 67(4): 2986-3003, 2024 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-38347756

RESUMO

Although ß2-agonists are crucial for treatment of chronic respiratory diseases, optimizing ß2-agonistic activity and selectivity remains essential for achieving favorable therapeutic outcomes. A structure-based molecular design workflow was employed to discover a novel class of ß2 agonists featuring a 5-hydroxy-4H-benzo[1,4]oxazin-3-one scaffold, which potently stimulated ß2 adrenoceptors (ß2-ARs). Screening for the ß2-agonistic activity and selectivity led to the identification of compound A19 (EC50 = 3.7 pM), which functioned as a partial ß2-agonist in HEK-293 cells containing endogenous ß2-ARs. Compound A19 exhibited significant relaxant effects, rapid onset time (Ot50 = 2.14 min), and long duration of action (>12 h) on isolated guinea pig tracheal strips, as well as advantageous pharmacokinetic characteristics in vivo, rendering A19 suitable for inhalation administration. Moreover, A19 suppressed the upregulation of inflammatory cytokines and leukocytes and improved lung function in a rat model of COPD, thereby indicating that A19 is a potential ß2 agonist candidate for further study.


Assuntos
Agonistas de Receptores Adrenérgicos beta 2 , Receptores Adrenérgicos beta 2 , Humanos , Ratos , Animais , Cobaias , Células HEK293 , Agonistas de Receptores Adrenérgicos beta 2/farmacologia
7.
Eur J Med Chem ; 265: 116071, 2024 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-38157596

RESUMO

In this study, a series of carbamate derivatives incorporating multifunctional carrier scaffolds were designed, synthesized, and evaluated as potential therapeutic agents for Alzheimer's disease (AD). We used tacrine to modify the aliphatic substituent, and employed rivastigmine, indole and sibiriline fragments as carrier scaffolds. The majority of compounds exhibited good inhibitory activity for cholinesterase. Notably, compound C7 with sibiriline fragment exhibited potent inhibitory activities against human acetylcholinesterase (hAChE, IC50 = 30.35 ± 2.07 nM) and human butyrylcholinesterase (hBuChE, IC50 = 48.03 ± 6.41 nM) with minimal neurotoxicity. Further investigations have demonstrated that C7 exhibited a remarkable capacity to safeguard PC12 cells against H2O2-induced apoptosis and effectively suppressed the production of reactive oxygen species (ROS). Moreover, in an inflammation model of BV2 cells induced by lipopolysaccharide (LPS), C7 effectively attenuated the levels of pro-inflammatory cytokines. After 12 h of dialysis, C7 continued to exhibit an inhibitory effect on cholinesterase activity. An acute toxicity test in vivo demonstrated that C7 exhibited a superior safety profile and no hepatotoxicity compared to the parent nucleus tacrine. In the scopolamine-induced AD mouse model, C7 (20 mg/kg) significantly reduced cholinesterase activity in the brain of the mice. C7 was tested in a pharmacological AD mouse model induced by Aß1-42 and attenuated memory deficits at doses as low as 5 mg/kg. The pseudo-irreversible cholinesterase inhibitory properties and multifunctional therapeutic attributes of C7 render it a promising candidate for further investigation in the treatment of AD.


Assuntos
Doença de Alzheimer , Inibidores da Colinesterase , Ratos , Camundongos , Humanos , Animais , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/induzido quimicamente , Butirilcolinesterase/metabolismo , Tacrina/farmacologia , Tacrina/uso terapêutico , Acetilcolinesterase/metabolismo , Carbamatos/farmacologia , Peróxido de Hidrogênio/farmacologia , Peptídeos beta-Amiloides , Barreira Hematoencefálica/metabolismo , Desenho de Fármacos , Relação Estrutura-Atividade
9.
Front Public Health ; 11: 1119710, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36778568

RESUMO

As a part of China's efforts to mitigate and control air pollution in key areas, the Air Pollution Prevention and Control Action Plan was implemented in 2013, and several regulatory measures were introduced. Based on the data from 271 prefecture-level cities between 2008 and 2018, the difference-in-differences model is used to explore the effect of it on sulfur dioxide intensity in our study, and several significant results are as follows: (1) The baseline results suggest a 23% reduction in sulfur dioxide intensity in pilot cities compared to non-pilot cities. (2) The total factor productivity fails to play a partial mediating role in reducing the sulfur dioxide intensity under the implementation of the policy. (3) The results of the triple differences model suggest that the policy still exerts significant adverse effects on sulfur dioxide intensity in the pilot areas of the carbon emission trading scheme.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Dióxido de Enxofre/análise , Poluentes Atmosféricos/análise , Poluição do Ar/prevenção & controle , Poluição do Ar/análise , China , Cidades
10.
Pathol Res Pract ; 240: 154235, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36434856

RESUMO

BACKGROUND: Triple-negative breast cancer (TNBC) is a special kind of breast cancer with strong ability of invasion and metastasis. UCHL1 belongs to the ubiquitin carboxy-terminal hydrolase family and is found to be increased in a variety of malignancies, but its expression in TNBC is unknown. METHODS: First, we analyzed the expression of UCHL1 in 128 TNBC specimens and paired adjacent normal tissues from 17 TNBC patients undergoing curative resection by immunohistochemistry. Then, the relationship between UCHL1 and cancer stemness was investigated by cell flow cytometry, spheroid formation assays and western blot. Moreover, cell scratch assay and Transwell assays were performed to explore whether UCHL1 promotes the migration and invasion of TNBC cells. Finally, we constructed a xenografts model of TNBC cell lines to observe the effect of UCHL1 on tumorigenesis in vivo. RESULTS: UCHL1 was overexpressed in TNBC tissues and associated with poor prognosis. UCHL1 promoted stem cancer cells properties, including the percentage of CD44+/CD24- cells, sphere-forming ability and CSCs related markers. Furthermore, Scratch assay and Transwell assay proved that UCHL1 enhanced the migration and invasion of TNBC cells. The experimental results of xenografts model in nude mice showed that UCHL1 promoted tumorigenesis of TNBC in vivo. CONCLUSION: UCHL1 may play a role in the malignant progression of TNBC by maintaining the stemness and promoting cell invasion and is expected to become a potential therapeutic target for TNBC patients.


Assuntos
Neoplasias de Mama Triplo Negativas , Ubiquitina Tiolesterase , Humanos , Animais , Camundongos , Camundongos Nus , Carcinogênese , Transformação Celular Neoplásica , Modelos Animais de Doenças
11.
J Am Chem Soc ; 144(30): 13973-13980, 2022 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-35878396

RESUMO

We report here an iterative synthesis of long helical perylene diimide (hPDI[n]) nanoribbons with a length up to 16 fused benzene rings. These contorted, ladder-type conjugated, and atomically precise nanoribbons show great potential as organic fast-charging and long-lifetime battery cathodes. By tuning the length of the hPDI[n] oligomers, we can simultaneously modulate the electrical conductivity and ionic diffusivity of the material. The length of the ladders adjusts both the conjugation for electron transport and the contortion for lithium-ion transport. The longest oligomer, hPDI[6], when fabricated as the cathode in lithium batteries, features both high electrical conductivity and high ionic diffusivity. This electrode material exhibits a high power density and can be charged in less than 1 min to 66% of its maximum capacity. Remarkably, this material also has exceptional cycling stability and can operate for up to 10,000 charging-discharging cycles without any appreciable capacity decay. The design principles described here chart a clear path for organic battery electrodes that are sustainable, fast-charging, and long lasting.

12.
Vet Med Sci ; 8(5): 2076-2085, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35894780

RESUMO

OBJECTIVE: In quantitative reverse transcription-polymerase chain reaction (RT-qPCR) studies, the selection and validation of reference genes are crucial for the accurate analysis of MicroRNAs (miRNAs) expression. In this work, the optimal reference genes for RT-qPCR normalisation in plasma samples of rat middle cerebral artery occlusion (MCAO) models were identified. METHODS: Six rat MCAO models were established. Blood samples were collected before modelling and approximately 16-24 h after modelling. Two commonly used reference genes (U6 and 5S) and three miRNAs (miR-24, miR-122 and miR-9a) were selected as candidate reference genes, and the expression of these genes was detected with RT-qPCR. The acquired data were analysed using geNorm, Normfinder, BestKeeper, RefFinder and comparative delta threshold cycle statistical models. RESULTS: The analysed results consistently showed that miR-24 was the most stably expressed reference gene. The 'optimal combination' calculated by geNorm was miR-24, U6 and5S. The expression level of the target gene miR124 was similar when the most stable reference gene miR-24 or the 'optimal combination' was used as a reference gene. However, compared with miR24 or the 'optimal combination', the less stable reference genes influenced the fold change and the data accuracy with a large standard deviation. CONCLUSION: These results confirmed the importance of selecting suitable reference genes for normalisation to obtain reliable results in RT-qPCR studies and demonstrated that the identified reference gene miR-24 or the 'optimal combination' could be used as an internal control for gene expression analysis in the rat MCAO model.


Assuntos
MicroRNAs , Doenças dos Roedores , Animais , Infarto da Artéria Cerebral Média/genética , Infarto da Artéria Cerebral Média/veterinária , MicroRNAs/genética , Ratos , Reação em Cadeia da Polimerase em Tempo Real/métodos , Reação em Cadeia da Polimerase em Tempo Real/veterinária
13.
Protein Sci ; 31(8): e4367, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35900024

RESUMO

Mouse double minute 2 homolog (MDM2) is an E3 ubiquitin-protein ligase that is involved in the transfer of ubiquitin to p53 and other protein substrates. The expression of MDM2 is elevated in cancer cells and inhibitors of MDM2 showed potent anticancer activities. Many inhibitors target the p53 binding domain of MDM2. However, inhibitors such as Inulanolide A and MA242 are found to bind the RING domain of MDM2 to block ubiquitin transfer. In this report, crystal structures of MDM2 RING domain in complex with Inulanolide A and MA242 were solved. These inhibitors primarily bind in a hydrophobic site centered at the sidechain of Tyr489 at the C-terminus of MDM2 RING domain. The C-terminus of MDM2 RING domain, especially residue Tyr489, is required for ubiquitin discharge induced by MDM2. The binding of these inhibitors at Tyr489 may interrupt interactions between the MDM2 RING domain and the E2-Ubiquitin complex to inhibit ubiquitin transfer, regardless of what the substrate is. Our results suggest a new mechanism of inhibition of MDM2 E3 activity for a broad spectrum of substrates.


Assuntos
Proteínas Proto-Oncogênicas c-mdm2 , Proteína Supressora de Tumor p53 , Animais , Camundongos , Ligação Proteica , Estrutura Terciária de Proteína , Proteínas Proto-Oncogênicas c-mdm2/metabolismo , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Ubiquitina/química , Ubiquitina-Proteína Ligases/metabolismo
14.
Chem Sci ; 13(12): 3533-3538, 2022 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-35432867

RESUMO

Redox-active two-dimensional polymers (RA-2DPs) are promising lithium battery organic cathode materials due to their regular porosities and high chemical stabilities. However, weak electrical conductivities inherent to the non-conjugated molecular motifs used thus far limit device performance and the practical relevance of these materials. We herein address this problem by developing a modular approach to construct π-conjugated RA-2DPs with a new polycyclic aromatic redox-active building block PDI-DA. Efficient imine-condensation between PDI-DA and two polyfunctional amine nodes followed by quantitative alkyl chain removal produced RA-2DPs TAPPy-PDI and TAPB-PDI as conjugated, porous, polycrystalline networks. In-plane conjugation and permanent porosity endow these materials with high electrical conductivity and high ion diffusion rates. As such, both RA-2DPs function as organic cathode materials with good rate performance and excellent cycling stability. Importantly, the improved design enables higher areal mass-loadings than were previously available, which drives a practical demonstration of TAPPy-PDI as the power source for a series of LED lights. Collectively, this investigation discloses viable synthetic methodologies and design principles for the realization of high-performance organic cathode materials.

15.
Nat Methods ; 19(3): 331-340, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35228726

RESUMO

Targeted insertion of large DNA fragments holds great potential for treating genetic diseases. Prime editors can effectively insert short fragments (~44 bp) but not large ones. Here we developed GRAND editing to precisely insert large DNA fragments without DNA donors. In contrast to prime editors, which require reverse transcription templates hybridizing with the target sequence, GRAND editing employs a pair of prime editing guide RNAs, with reverse transcription templates nonhomologous to the target site but complementary to each other. This strategy exhibited an efficiency of up to 63.0% of a 150-bp insertion with minor by-products and 28.4% of a 250-bp insertion. It allowed insertions up to ~1 kb, although the efficiency remains low for fragments larger than 400 bp. We confirmed efficient insertion in multiple genomic loci of several cell lines and non-dividing cells, which expands the scope of genome editing to enable donor-free insertion of large DNA sequences.


Assuntos
Edição de Genes , RNA Guia de Cinetoplastídeos , Sistemas CRISPR-Cas , DNA/genética , Genoma , Genômica , RNA Guia de Cinetoplastídeos/genética
16.
J Rehabil Med Clin Commun ; 4: 1000069, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34703526

RESUMO

CASE REPORT: We report the effect of a 6-week outpatient (phase II) cardiac rehabilitation in a 38-year-old man with post-stented coarctation of the aorta, moyamoya disease and hypertension. The cardiac rehabilitation programme comprised physiotherapist-guided aerobic exercises, resistance training and relaxation exercises. Clinical and functional assessment was performed before and after the cardiac rehabilitation programme. DISCUSSION: There is a lack of recommendations to guide cardiac rehabilitation in patients with coarctation of the aorta. This case not only had coarctation of the aorta, but also had moyamoya disease and hypertension. A cardiac rehabilitation programme after surgery provided meaningful improvements in all outcomes, including exercise capacity, clinical outcomes, quality of life and depression symptoms. Systematic cardiac rehabilitation was found to be feasible in this patient with coarctation of the aorta, and may have the potential to benefit more patients. CONCLUSION: Cardiac rehabilitation resulted in significant clinical and functional improvements in this case with coarctation of the aorta following surgery. Guidelines should be implemented to provide safe and effective cardiac rehabilitation in such patients. Furthermore, large-scale studies are needed to evaluate the clinical benefits of structured cardiac rehabilitation in patients following cardiac surgery.

17.
Oncogene ; 40(33): 5182-5191, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34218269

RESUMO

Uveal melanoma (UM) is the most prevalent primary intraocular malignancy in adults, and patients that develop metastases (~50%) survive <1 year, highlighting the urgent need for new therapies. TCGA has recently revealed that a hypoxia gene signature is associated with poor UM patient prognosis. Here we show that expression of hypoxia-regulated collagen prolyl-4-hydroxylase genes P4HA1 and P4HA2 is significantly upregulated in UM patients with metastatic disease and correlates with poor prognosis, suggesting these enzymes might be key tumor drivers. We targeted hypoxia-induced expression of P4HA1/2 in UM with KCN1, a hypoxia inducible factor-1 (HIF-1) pathway inhibitor and found potent inhibition of primary and metastatic disease and extension of animal survival, without overt side effects. At the molecular level, KCN1 antagonized hypoxia-induced expression of P4HA1 and P4HA2, which regulate collagen maturation and deposition in the extracellular matrix. The treatment decreased prolyl hydroxylation, induced proteolytic cleavage and rendered a disordered structure to collagen VI, the main collagen produced by UM, and reduced UM cell invasion. Together, these data demonstrate that extracellular collagen matrix formation can be targeted in UM by inhibiting hypoxia-induced P4HA1 and P4HA2 expression, warranting further development of this strategy in patients with uveal melanoma.


Assuntos
Prolina Dioxigenases do Fator Induzível por Hipóxia , Matriz Extracelular , Humanos , Hidroxilação , Melanoma , Ativação Transcricional , Regulação para Cima , Neoplasias Uveais
18.
Int J Mol Sci ; 22(5)2021 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-33801310

RESUMO

BACKGROUND: The molecular regulation of increased MGMT expression in human brain tumors, the associated regulatory elements, and linkages of these to its epigenetic silencing are not understood. Because the heightened expression or non-expression of MGMT plays a pivotal role in glioma therapeutics, we applied bioinformatics and experimental tools to identify the regulatory elements in the MGMT and neighboring EBF3 gene loci. RESULTS: Extensive genome database analyses showed that the MGMT genomic space was rich in and harbored many undescribed RNA regulatory sequences and recognition motifs. We extended the MGMT's exon-1 promoter to 2019 bp to include five overlapping alternate promoters. Consensus sequences in the revised promoter for (a) the transcriptional factors CTCF, NRF1/NRF2, GAF, (b) the genetic switch MYC/MAX/MAD, and (c) two well-defined p53 response elements in MGMT intron-1, were identified. A putative protein-coding or non-coding RNA sequence was located in the extended 3' UTR of the MGMT transcript. Eleven non-coding RNA loci coding for miRNAs, antisense RNA, and lncRNAs were identified in the MGMT-EBF3 region and six of these showed validated potential for curtailing the expression of both MGMT and EBF3 genes. ChIP analysis verified the binding site in MGMT promoter for CTCF which regulates the genomic methylation and chromatin looping. CTCF depletion by a pool of specific siRNA and shRNAs led to a significant attenuation of MGMT expression in human GBM cell lines. Computational analysis of the ChIP sequence data in ENCODE showed the presence of NRF1 in the MGMT promoter and this occurred only in MGMT-proficient cell lines. Further, an enforced NRF2 expression markedly augmented the MGMT mRNA and protein levels in glioma cells. CONCLUSIONS: We provide the first evidence for several new regulatory components in the MGMT gene locus which predict complex transcriptional and posttranscriptional controls with potential for new therapeutic avenues.


Assuntos
Biomarcadores Tumorais/metabolismo , Metilases de Modificação do DNA/metabolismo , Enzimas Reparadoras do DNA/metabolismo , Epigênese Genética , Regulação Neoplásica da Expressão Gênica , Glioma/metabolismo , Sequências Reguladoras de Ácido Nucleico , Proteínas Supressoras de Tumor/metabolismo , Biomarcadores Tumorais/genética , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patologia , Fator de Ligação a CCCTC/genética , Fator de Ligação a CCCTC/metabolismo , Metilação de DNA , Metilases de Modificação do DNA/genética , Enzimas Reparadoras do DNA/genética , Genômica , Glioma/genética , Glioma/patologia , Humanos , Fator 2 Relacionado a NF-E2/genética , Fator 2 Relacionado a NF-E2/metabolismo , Fator 1 Nuclear Respiratório/genética , Fator 1 Nuclear Respiratório/metabolismo , Regiões Promotoras Genéticas , RNA Interferente Pequeno/genética , RNA não Traduzido/genética , Proteínas Supressoras de Tumor/genética
19.
J Control Release ; 333: 339-351, 2021 05 10.
Artigo em Inglês | MEDLINE | ID: mdl-33766692

RESUMO

Enhancing thermogenic energy expenditure via promoting the browning of white adipose tissue (WAT) is a potential therapeutic strategy to manage energy imbalance and the consequent comorbidities associated with excess body weight. Adverse effects and toxicities of currently available methods to induce browning of WAT have retarded exploration of this promising therapeutic approach. Targeted delivery of browning agents to adipose stromal cells (ASCs) in subcutaneous WAT to induce differentiation into beige adipocytes may overcome these barriers. Herein, we report for the first time, ASC-targeted delivery of trans-resveratrol (R), a representative agent, using ligand-coated R-encapsulated nanoparticles (L-Rnano) that selectively bind to glycanation site-deficient decorin receptors on ASCs. After biweekly intravenous administration of L-Rnano to obese C57BL/6 J mice for 5 weeks targeted R delivery significantly induced ASCs differentiation into beige adipocytes, which subsequently resulted in 40% decrease in fat mass, accompanied by improved glucose homeostasis and decreased inflammation. Our results suggest that the ASC-targeted nanoparticle delivery of browning agents could be a transformative technology in combating obesity and its comorbidities with high efficacy and low toxicity.


Assuntos
Nanopartículas , Termogênese , Tecido Adiposo Branco , Animais , Camundongos , Camundongos Endogâmicos C57BL , Obesidade/tratamento farmacológico , Resveratrol , Células Estromais
20.
PLoS One ; 16(1): e0245829, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33493172

RESUMO

BACKGROUND: Current clinical evidence suggests that a well-planned physiotherapeutic scoliosis specific exercise (PSSE) program is effective for scoliosis regression. OBJECTIVES: We investigated the effect of curve patterns on Cobb angles with PSSE. METHODS: This was a non-randomized prospective clinical trial that recruited participants with adolescent idiopathic scoliosis between January and June 2017. Participants were grouped by curve pattern into major thoracic and major lumbar groups. An outpatient-based PSSE program was conducted with the following schedule of intensive exercise: ≥ 1 session of supervised PSSE per month and > 30min of home exercise 5 days/week in the first 6 months, after which exercise frequency was reduced to 1 session of supervised PSSE every three months and > 30min of home exercise 5 days/week until 2 years after study initiation. Radiographic Cobb angle progressions were identified at the 1, 1.5 and 2-year follow-ups. A mixed model analysis of variance (ANOVA) was performed to examine the differences in Cobb angles between groups at four testing time points. The two-tailed significance level was set to 0.05. RESULTS: In total, 40 participants were recruited, including 22 with major thoracic curves (5 males and 17 females; mean age 13.5±1.8 years; Cobb angle 18-45 degrees) and 18 with major lumbar curves (7 males and 11 females; mean age 12.7±1.7 years; Cobb angle 15-48 degrees). Curve regressions, namely the reduction of Cobb angles between 7 to 10 degrees were noted in 9.1% of participants in the major thoracic group; reductions of 6 to 13 degrees were noted in 33.3% of participants in the major lumbar group at the 2-year follow-up. Repeated measurements revealed a significant time effect (F2.2,79.8 = 4.1, p = 0.02), but no group (F2.2,79.8 = 2.3, p = 0.1) or time × group (F1,37 = 0.97, p = 0.3) effects in reducing Cobb angles after 2 years of PSSE. A logistic regression analysis revealed that no correlation was observed between curve pattern and curve regression or stabilization (OR: 0.2, 95% CI: 0.31-1.1, p = 0.068) at the 2-year follow-up. CONCLUSION: This was the first study to investigate the long-term effects of PSSE in reducing Cobb angles on the basis of major curve location. No significant differences in correction were observed between major thoracic and major lumbar curves. A regression effect and no curve deterioration were noted in both groups at the 2-year follow-up. TRIAL REGISTRATION: ChiCTR1900028073.


Assuntos
Terapia por Exercício , Vértebras Lombares/patologia , Escoliose/patologia , Escoliose/terapia , Vértebras Torácicas/patologia , Adolescente , Criança , Feminino , Seguimentos , Humanos , Masculino , Estudos Prospectivos , Resultado do Tratamento
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