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1.
Drug Resist Updat ; 76: 101122, 2024 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-39079407

RESUMO

O6-methylguanine DNA methyltransferase (MGMT) is a crucial determinant of temozolomide (TMZ) sensitivity in patients with glioblastoma (GBM). The therapeutic potential of small interfering RNA (siRNA) targeting MGMT to enhance TMZ sensitivity has been hampered by serum nuclease degradation, off-target effects, poor accumulation at tumor sites, and low circulation in blood stream. In this study, we developed a framework nucleic acid-based nanoparticles (FNN), which is constructed from a six-helix DNA bundle, to encapsulate and protect siMGMT for improving TMZ sensitivity in GBM treatment. For better blood-brain barrier (BBB) penetration and GBM targeting, we conjugated Angiopep-2 (ANG) targeting modules to each end of the FNN. Nucleolin (NCL)-responsive locks were engineered along the sides of the six-helix DNA bundle, which safeguard siMGMT before tumor entry. Upon interaction with tumor-overexpressed NCL, these locks unlock, exposing siMGMT, this allows for effective suppression of MGMT, resulting in a significant improvement of TMZ therapeutic efficacy in GBM. This innovative strategy has the potential to transform the current treatment landscape for GBM.

2.
Adv Sci (Weinh) ; 11(19): e2309290, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38477507

RESUMO

Temozolomide (TMZ) resistance remains the major obstacle in the treatment of glioblastoma (GBM). Lactylation is a novel post-translational modification that is involved in various tumors. However, whether lactylation plays a role in GBM TMZ resistance remains unclear. Here it is found that histone H3K9 lactylation (H3K9la) confers TMZ resistance in GBM via LUC7L2-mediated intron 7 retention of MLH1. Mechanistically, lactylation is upregulated in recurrent GBM tissues and TMZ-resistant cells, and is mainly concentrated in histone H3K9. Combined multi-omics analysis, including CUT&Tag, SLAM-seq, and RNA-seq, reveals that H3K9 lactylation is significantly enriched in the LUC7L2 promoter and activates LUC7L2 transcription to promote its expression. LUC7L2 mediates intron 7 retention of MLH1 to reduce MLH1 expression, and thereby inhibit mismatch repair (MMR), ultimately leading to GBM TMZ resistance. Of note, it is identified that a clinical anti-epileptic drug, stiripentol, which can cross the blood-brain barrier and inhibit lactate dehydrogenase A/B (LDHA/B) activity, acts as a lactylation inhibitor and renders GBM cells more sensitive to TMZ in vitro and in vivo. These findings not only shed light on the mechanism of lactylation in GBM TMZ resistance but also provide a potential combined therapeutic strategy for clinical GBM treatment.


Assuntos
Resistencia a Medicamentos Antineoplásicos , Glioblastoma , Histonas , Íntrons , Proteína 1 Homóloga a MutL , Temozolomida , Animais , Humanos , Camundongos , Antineoplásicos Alquilantes/farmacologia , Antineoplásicos Alquilantes/uso terapêutico , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/metabolismo , Linhagem Celular Tumoral , Modelos Animais de Doenças , Resistencia a Medicamentos Antineoplásicos/genética , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Glioblastoma/genética , Glioblastoma/tratamento farmacológico , Glioblastoma/metabolismo , Histonas/metabolismo , Histonas/genética , Íntrons/genética , Camundongos Nus , Proteína 1 Homóloga a MutL/genética , Proteína 1 Homóloga a MutL/metabolismo , Temozolomida/farmacologia , Feminino
3.
iScience ; 26(8): 107377, 2023 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-37520713

RESUMO

The prognosis of glioblastoma (GBM) patients is poor, and temozolomide (TMZ) resistance has become an important obstacle to its treatment effect. A growing number of researches have revealed the special characteristics of iron metabolism in GBM chemosensitivity. Iron regulatory protein 1 (IRP1) is an important protein for maintaining intracellular iron homeostasis. IRP1 has been indicated to have additional vital roles beyond its conventional metabolic activity, but the underlying mechanisms and biological consequences remain elusive. Here, we unprecedentedly demonstrated that amplifying IRP1 signals can reverse TMZ resistance and suppress tumor growth in vivo via inhibiting NFKB2 in the noncanonical NF-κB signaling pathway. In addition, we identified that NFKB2 affected TMZ sensitivity of GBM by modulating the expression of LCN2 and FPN1. Taken together, this study established a role for the IRP1/NFKB2 pathway in regulating LCN2/FPN1 signaling axis among the progression of TMZ resistance, suggesting a potential innovative GBM therapeutic strategy.

4.
Mol Ther Nucleic Acids ; 24: 768-779, 2021 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-33996258

RESUMO

N 6-methyladenosine (m6A) is the most abundant modification in eukaryotic cells, and it regulates RNA transcription, processing, splicing, degradation, and translation. Long non-coding RNAs (lncRNAs), as transcriptional products with no or limited protein coding ability more than 200 nt in length, play an important role in epigenetic modification, mRNA transcription, splicing, stability, translation, and other biological functions. Extensive studies have shown that both m6A modification and lncRNAs are involved in the pathogenesis of various diseases, such as kinds of cancers, heart failure, Alzheimer's disease, periodontitis, human abdominal aortic aneurysm, and obesity. To date, m6A modification has been identified as an important biological function in enrichment and regulation of lncRNAs. In this review, we summarize the role of m6A modification in the regulation and function of tumor-related lncRNAs. Moreover, we discuss the potential applications and possible future directions in the field.

5.
PLoS One ; 14(7): e0219803, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31318930

RESUMO

This paper attempts to design an automated, efficient and intelligent tomato grading method that facilitates the graded selling of the fruit. Based on machine vision, the color images of tomatoes with different morphologies were studied, and the color, shape and size were selected as the key features. On this basis, an automated grading classifier was created based on the surface features of tomatoes, and a grading platform was set up to verify the effect of the classifier. Specifically, the Hue value distributions of tomatoes with different maturities were investigated, and the Hue value ranges were determined for mature, semi-mature and immature tomatoes, producing the color classifier. Next, the first-order Fourier descriptor (1D- FD) was adopted to describe the radius sequence of tomato contour, and an equation was established to compute the irregularity of tomato contour, creating the shape classifier. After that, a linear regression equation was constructed to reflect the relationship between the transverse diameters of actual tomatoes and tomato images, and a classifier between large, medium and small tomatoes was produced based on the transverse diameter. Finally, a comprehensive tomato classifier was built based on the color, shape and size diameters. The experimental results show that the mean grading accuracy of the proposed method was 90.7%. This means our method can achieve automated real-time grading of tomatoes.


Assuntos
Aprendizado de Máquina , Fenótipo , Solanum lycopersicum/classificação , Algoritmos , Humanos , Reprodutibilidade dos Testes
6.
Sci Rep ; 8(1): 7574, 2018 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-29765084

RESUMO

The present work was designed to evaluate the antioxidation and hepatoprotective effects of Auricularia cornea var. Li. polysaccharides (APS) and enzymatic-extractable APS (EAPS) on the acute alcohol-induced alcoholic liver diseases (ALD). The in vitro antioxidant activities demonstrated that both APS and EAPS had strong reducing power and potential effects on scavenging reactive oxygen species. The in vivo mice experiments showed that the pretreatment with APS or EAPS showed potential hepatoprotective effects on the ALD possibly by increasing the antioxidant activities, reducing the lipid peroxidation, improving the alcohol metabolism, inhibiting the expression levels of inflammatory mediators and preventing the alcohol-induced histopathological alterations. In addition, the fourier-transform infrared (FT-IR), 1H and 13C nuclear magnetic resonance spectroscopy (NMR) and gas chromatography (GC) had been analyzed to obtained the primarily characteristics. The results indicated that abundant xylose and glucose contents probably had potential effects on possessing the bioactivities. The findings suggested that the A. cornea var. Li. might be considered as promising natural resource on exploring clinical drugs for the prevention and treatment with ALD and its complications.


Assuntos
Agaricales/química , Antioxidantes/administração & dosagem , Polissacarídeos Fúngicos/administração & dosagem , Hepatopatias Alcoólicas/tratamento farmacológico , Animais , Antioxidantes/química , Antioxidantes/farmacologia , Cromatografia Gasosa , Modelos Animais de Doenças , Polissacarídeos Fúngicos/química , Polissacarídeos Fúngicos/farmacologia , Glucose/isolamento & purificação , Glucose/farmacologia , Peroxidação de Lipídeos/efeitos dos fármacos , Hepatopatias Alcoólicas/metabolismo , Masculino , Camundongos , Espectroscopia de Prótons por Ressonância Magnética , Espécies Reativas de Oxigênio/metabolismo , Espectroscopia de Infravermelho com Transformada de Fourier , Resultado do Tratamento , Xilose/isolamento & purificação , Xilose/farmacologia
7.
Sci Rep ; 8(1): 2048, 2018 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-29391516

RESUMO

The present work was designed to investigate the characterization, as well as the antioxidation and renoprotection in streptozocin (STZ)-induced diabetic mice, of exopolysaccharides (EPS) and the enzymatic-EPS (EEPS) and acidic-EPS (AEPS) hydrolysates, which were separated from the fermentation liquor of Hypsizigus marmoreus. Animal results demonstrated that EPS, EEPS and AEPS had potential antioxidant and renoprotective effects, especially EEPS. Additionally, they were the most effective, reflecting increases in superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), catalase (CAT), total antioxidant capacity (T-AOC), and albumin (ALB) of 168.33%, 124.8%, 268.17% 179.49%, and 68.71%, respectively, and decreases in the contents of malondialdehyde (MDA), lipid peroxide (LPO) and levels of serum urea nitrogen (BUN) and creatinine (CRE) by 70.58%, 58.43%, 23.97% and 29.60%, respectively, at a dose of 800 mg/kg compared to those of model mice. Three polysaccharides ameliorated the histopathological alterations which were observed in the kidney of diabetic mice. Furthermore, the characterization of polysaccharides had been expressed. These findings indicated that the EEPS from H. marmoreus possesses more effective renoprotection and antioxidation effects and provided insight into its potential clinical values on preventing diabetes.


Assuntos
Agaricales/química , Antioxidantes/farmacologia , Polissacarídeos Fúngicos/farmacologia , Rim/efeitos dos fármacos , Animais , Antioxidantes/química , Catalase/metabolismo , Nefropatias Diabéticas/tratamento farmacológico , Polissacarídeos Fúngicos/química , Glutationa Peroxidase/metabolismo , Rim/metabolismo , Peroxidação de Lipídeos , Malondialdeído/metabolismo , Camundongos , Superóxido Dismutase/metabolismo
8.
Oxid Med Cell Longev ; 2017: 5863523, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29430281

RESUMO

In order to contribute to the exploitation and utilization of spent mushroom substrates (SMS) of Laetiporus sulphureus, hot-water-extractable polysaccharides (H-SMPS) and enzymatic-extractable polysaccharides (E-SMPS) were successfully isolated from SMS of L. sulphureus. Both H-SMPS and E-SMPS were found to have high reducing power and potential scavenging activities against hydroxyl, DPPH, and superoxide anion radicals. In vivo assays showed that the administration of H-SMPS and E-SMPS has potential hepatoprotective effects against alcohol-induced alcoholic liver disease (ALD), possibly brought about by improving liver function, increasing antioxidant status, and reducing lipid peroxidation. Furthermore, monosaccharide composition analysis showed that fucose may play a vital role in guaranteeing stronger hepatoprotection. These results may provide references for the exploitation of the SMS of L. sulphureus as a source of H-SMPS and E-SMPS, which in turn can be used as functional foods or natural drugs for the prevention of ALD and other liver diseases.


Assuntos
Agaricales/química , Antioxidantes/uso terapêutico , Hepatopatias Alcoólicas/tratamento farmacológico , Polissacarídeos/metabolismo , Animais , Antioxidantes/farmacologia , Hepatopatias Alcoólicas/patologia , Camundongos
9.
Virus Res ; 191: 62-9, 2014 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-25076104

RESUMO

Multiple plant viruses, including potato virus X (PVX), have been modified as vectors for expressing heterologous genes or silencing endogenous genes in plants. PVX-based vectors facilitate the functional analysis of genes in plant. However, they can only express one protein in a time. In this paper we report the construction of new vectors based on a 35S promoter-driven PVX infectious clone, pCaPVX100. Vector pCaPVX440 contains two additional subgenomic promoters and can be utilized to express two foreign genes at the same time. Plasmid pCaPVX760 is a CP minus vector and can be used to express foreign proteins through the gene substitution strategy. In addition, plasmid pCaPVX100 was engineered into a gene silencing vector (pCaPVX440-LIC) by introducing a ligation independent cloning (LIC) site into the vector. These results indicate that the newly developed PVX vectors are competent for multiple research purposes.


Assuntos
Expressão Gênica , Inativação Gênica , Marcação de Genes/instrumentação , Vetores Genéticos/genética , Plantas/genética , Potexvirus/genética , Clonagem Molecular , Vetores Genéticos/metabolismo , Potexvirus/metabolismo
10.
Virus Genes ; 35(3): 801-6, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17668310

RESUMO

The complete genomic sequence of an isolate of Tobacco vein banding mosaic virus (TVBMV-YND) from Yunnan, China was determined by sequencing overlapping cDNA fragments obtained by RT-PCR with degenerate and/or specific primers. The genome is composed of 9,570 nucleotides (nt) excluding the 3'-terminal poly (A) tail and contains one single open reading frame of 9,240 nt encoding a large polyprotein of 3,079 amino acids with predicted Mr of 348.6 kDa. Phylogenetic analysis of complete genomic sequences confirmed that TVBMV is a distinct species of the genus Potyvirus. Different parts of TVBMV-YND genome shared different levels of identity with other species of potyviruses, while most parts showed greatest identity with Chilli veinal mottle virus among the potyviruses with available complete genomic sequences. TVBMV-YND had a rare Q/N cleavage site for NIb/CP and uncommon RITC motif in HC-Pro that is crucial for aphid transmission of potyviruses.


Assuntos
Genoma Viral , Nicotiana/virologia , Potyvirus/classificação , Potyvirus/genética , Motivos de Aminoácidos/genética , Sequência de Bases , China , DNA Complementar/química , DNA Complementar/genética , Transmissão de Doença Infecciosa , Dados de Sequência Molecular , Peso Molecular , Fases de Leitura Aberta , Filogenia , Poliproteínas/química , Poliproteínas/genética , Potyvirus/isolamento & purificação , RNA Mensageiro/genética , RNA Viral/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Análise de Sequência de DNA , Homologia de Sequência , Proteínas Virais/química , Proteínas Virais/genética
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