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1.
Cell ; 158(1): 143-156, 2014 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-24995985

RESUMO

Mechanical forces have been proposed to modulate organ growth, but a molecular mechanism that links them to growth regulation in vivo has been lacking. We report that increasing tension within the cytoskeleton increases Drosophila wing growth, whereas decreasing cytoskeletal tension decreases wing growth. These changes in growth can be accounted for by changes in the activity of Yorkie, a transcription factor regulated by the Hippo pathway. The influence of myosin activity on Yorkie depends genetically on the Ajuba LIM protein Jub, a negative regulator of Warts within the Hippo pathway. We further show that Jub associates with α-catenin and that its localization to adherens junctions and association with α-catenin are promoted by cytoskeletal tension. Jub recruits Warts to junctions in a tension-dependent manner. Our observations delineate a mechanism that links cytoskeletal tension to regulation of Hippo pathway activity, providing a molecular understanding of how mechanical forces can modulate organ growth.


Assuntos
Citoesqueleto/metabolismo , Proteínas de Drosophila/metabolismo , Drosophila/crescimento & desenvolvimento , Proteínas com Domínio LIM/metabolismo , Transdução de Sinais , Asas de Animais/crescimento & desenvolvimento , Animais , Fenômenos Biomecânicos , Drosophila/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Proteínas Nucleares/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Transativadores/metabolismo , Asas de Animais/metabolismo , Proteínas de Sinalização YAP
2.
Mol Cell ; 81(6): 1216-1230.e9, 2021 03 18.
Artigo em Inglês | MEDLINE | ID: mdl-33606996

RESUMO

Interferon-γ (IFN-γ)-mediated adaptive resistance is one major barrier to improving immunotherapy in solid tumors. However, the mechanisms are not completely understood. Here, we report that IFN-γ promotes nuclear translocation and phase separation of YAP after anti-PD-1 therapy in tumor cells. Hydrophobic interactions of the YAP coiled-coil domain mediate droplet initiation, and weak interactions of the intrinsically disordered region in the C terminus promote droplet formation. YAP partitions with the transcription factor TEAD4, the histone acetyltransferase EP300, and Mediator1 and forms transcriptional hubs for maximizing target gene transcriptions, independent of the canonical STAT1-IRF1 transcription program. Disruption of YAP phase separation reduced tumor growth, enhanced immune response, and sensitized tumor cells to anti-PD-1 therapy. YAP activity is negatively correlated with patient outcome. Our study indicates that YAP mediates the IFN-γ pro-tumor effect through its nuclear phase separation and suggests that YAP can be used as a predictive biomarker and target of anti-PD-1 combination therapy.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Resistencia a Medicamentos Antineoplásicos , Inibidores de Checkpoint Imunológico/farmacologia , Imunoterapia , Interferon gama/metabolismo , Neoplasias Experimentais , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Fatores de Transcrição/metabolismo , Células A549 , Proteínas Adaptadoras de Transdução de Sinal/genética , Animais , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/genética , Células HEK293 , Humanos , Interferon gama/genética , Camundongos , Camundongos Knockout , Neoplasias Experimentais/genética , Neoplasias Experimentais/metabolismo , Neoplasias Experimentais/patologia , Neoplasias Experimentais/terapia , Receptor de Morte Celular Programada 1/genética , Receptor de Morte Celular Programada 1/metabolismo , Fatores de Transcrição/genética , Proteínas de Sinalização YAP
3.
Nat Chem Biol ; 20(6): 710-720, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38200110

RESUMO

Biomolecular condensates have been proposed to mediate cellular signaling transduction. However, the mechanism and functional consequences of signal condensates are not well understood. Here we report that LATS2, the core kinase of the Hippo pathway, responds to F-actin cytoskeleton reduction and forms condensates. The proline-rich motif (PRM) of LATS2 mediates its condensation. LATS2 partitions with the main components of the Hippo pathway to assemble a signalosome for LATS2 activation and for its stability by physically compartmentalizing from E3 ligase FBXL16 complex-dependent degradation, which in turn mediates yes-associated protein (YAP)-transcriptional coactivator with PDZ-binding motif (TAZ) recruitment and inactivation. This oncogenic FBXL16 complex blocks LATS2 condensation by binding to the PRM region to promote its degradation. Disruption of LATS2 condensation leads to tumor progression. Thus, our study uncovers that the signalosomes assembled by LATS2 condensation provide a compartmentalized and reversible platform for Hippo signaling transduction and protein stability, which have potential implications in cancer diagnosis and therapeutics.


Assuntos
Via de Sinalização Hippo , Proteínas Serina-Treonina Quinases , Transdução de Sinais , Proteínas Supressoras de Tumor , Proteínas Serina-Treonina Quinases/metabolismo , Humanos , Proteínas Supressoras de Tumor/metabolismo , Células HEK293 , Animais , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Linhagem Celular Tumoral , Camundongos , Proteínas de Sinalização YAP/metabolismo , Fatores de Transcrição/metabolismo
4.
Crit Rev Food Sci Nutr ; : 1-16, 2023 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-38116946

RESUMO

Peptides are important components of human nutrition and health, and considered as safe, nontoxic, and easily absorbed potential drugs. Anti-hypoxia peptides are a kind of peptides that can prevent hypoxia or hypoxia damage. In this paper, the sources, preparations, and molecular mechanisms of anti-hypoxia peptides were systemically reviewed. The combination of bioinformatics, chemical synthesis, enzymatic hydrolysis, and microbial fermentation are recommended for efficient productions of anti-hypoxic peptides. The mechanisms of anti-hypoxic peptides include interference with glycolytic process and HIF-1α pathway, mitochondrial apoptosis, and inflammatory response. In addition, bioinformatics analysis, including virtual screening and molecular docking, provides an alternative or auxiliary method for exploring the potential anti-hypoxic activities and mechanisms of peptides. The potential challenges and prospects of anti-hypoxic peptides are also discussed. This paper can provide references for researchers in this field and promote further research and clinical applications of anti-hypoxic peptides in the future.

5.
Crit Rev Food Sci Nutr ; : 1-15, 2022 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-36315046

RESUMO

Quinoa is known to be a rich source of nutrients and bioactive components. Quinoa bran, used mainly as animal feed in processing by-products, is also a potential source of bioactive ingredients being conducive to human health. The importance of nutrition and function of quinoa seed has been discussed in many studies, but the bioactive properties of quinoa bran often are overlooked. This review systemically summarized the progress in bioactive components, extraction, and functional investigations of quinoa bran. It suggests that chemically assisted electronic fractionation could be used to extract albumin from quinoa bran. Ultrasound-assisted extraction method is a very useful method for extracting phenolic acids, triterpene saponins, and flavonoids from quinoa bran. Based on in vitro and in vivo studies for biological activities, quinoa bran extract exhibits a wide range of beneficial properties, including anti-oxidant, anti-diabetes, anti-inflammation, anti-bacterial and anti-cancer functions. However, human experiments and action mechanisms need to investigate. Further exploring quinoa bran will promote its applications in functional foods, pharmaceuticals, and poultry feed in the future.

6.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 38(9): 838-840, 2021 Sep 10.
Artigo em Zh | MEDLINE | ID: mdl-34487525

RESUMO

OBJECTIVE: To explore the genetic basis for a Chinese pedigree affected with resistance to thyroid hormone syndrome (RTH). METHODS: Exons 7 to 10 of the THRbeta gene were sequenced for the proband and members of his pedigree. RESULTS: Three patients from the pedigree were identified. All have presented with palpitation, fatigue, goiter, elevated free thyroid hormone and free triiodothyronine, and normal or elevated thyrotropin. Genetic testing revealed that the proband, his mother, second sister and one of her daughters had carried a heterozygous c.1336T>A variant of the THRbeta gene, which resulted in substitution of Cysteine by Serine at position 446. The variant was unreported previously. Based on the American College of Medical Genetics and Genomics standards and guidelines, the c.1336T>A(p.Cys446Ser) variant of THRbeta gene was predicted to be lilely pathogenic(PM1+PM2+PM5+PP3). CONCLUSION: The c.1336T>A variant, identified in the exon 10 of the THRbeta gene, probably underlay the RTH in this pedigree. Genetic testing has validated the clinical diagnosis for this pedigree.


Assuntos
Genômica , Mães , Feminino , Heterozigoto , Humanos , Mutação , Linhagem
7.
J Food Sci Technol ; 57(4): 1351-1361, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32180631

RESUMO

In this study, the physicochemical properties (total volatile basic nitrogen (TVB-N), pH, and peroxide value) and the volatile flavors of yak meat were systematically evaluated during chilled (0 °C) and controlled freezing-point (- 2 °C) storage. The TVB-N reached 15.21 mg/100 g after 18 days of storage at 0 °C, which exceeded the secondary freshness value according to the Chinese national standard. For storage at - 2 °C, the TVB-N did not exceed 15 mg/100 g until 24 days. Compared with storage at 0 °C, the samples stored at - 2 °C had a slower rate of increase in TVB-N, pH, and peroxide values. The changes in volatile compounds in yak meat during storage at - 2 °C and 0 °C for 24 days were investigated using headspace solid-phase microextraction (HS-SPME) followed by gas chromatography-mass spectrometry (GC-MS). The correlations between the changes in the volatile compound contents and meat quality deterioration revealed significant negative correlations (r min = 0.902, p < 0.05) between some aldehyde flavor components (nonanal, heptanal, benzaldehyde, decanal, and myristal) and TVB-N in the samples stored at controlled freezing-point and chilled temperatures. The decreases in nonanal, benzaldehyde, and myristal contents in yak meat followed zero order reaction kinetics. This result indicated, because of the highly selective and sensitive colorimetric detection method, that volatile compounds can effectively predict the decay in quality of yak meat stored at low temperature in advance. Thus, based on physicochemical and volatile flavor analyses, a new method is proposed to investigate the storage and preservation of yak meat.

8.
Yi Chuan ; 39(7): 537-545, 2017 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-28757469

RESUMO

The discovery of Hippo signaling pathway is another breakthrough of fly genetics. Similar to the other signaling pathways, Hippo pathway also functions crucially in tremendous physiological and pathological conditions, like organ size control and cancer. There are three main stages of Hippo pathway study: Firstly, identifications of core components by fly genetic screens; secondly, regulations by versatile upstream cues, like cytoskeleton, mechanical tension, and nutrition; thirdly, functions in different biological processes, like cell proliferation regulation, stem cell biology, and immunology. In this review, we summarize the current understanding of Hippo pathway and highlight its regulations and transcriptional complex assembly. We also discuss the potential future directions in Drosophila model system.


Assuntos
Proteínas de Drosophila/fisiologia , Peptídeos e Proteínas de Sinalização Intracelular/fisiologia , Proteínas Serina-Treonina Quinases/fisiologia , Transdução de Sinais/fisiologia , Animais , Drosophila , Transcrição Gênica
9.
Bioprocess Biosyst Eng ; 38(10): 2023-34, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26224655

RESUMO

A simple optimization method of immobilization of avidin on magnetic nanoparticles (MNPs)' surface was proposed in this study. The avidin-immobilized MNPs were then developed and used to immobilize a model enzyme [Horseradish peroxidase (HRP)]. The loading capacity (LC) and activity of avidin-immobilized MNPs were optimized through selecting the most appropriate nanoparticle's size and shape, glutaraldehyde concentration, cross-linking reaction time, ultrasonic processing time, and initial concentration of avidin. The LC under optimized conditions was 63.37 ± 1.29 mg avidin/g MNPs, and the immobilized protein was still able to maintain its high biological activity of 10.86 ± 0.13 U/mg (biotin-binding activity of nature avidin was 14.1 U/mg) and better thermal stability compared to free avidin. A highly reusable, stable, and easily recovered immobilized HRP was obtained using MNPs as carriers. The immobilized HRP was reused repeatedly more than 9 times and retained more than 65 % of its original activity.


Assuntos
Avidina/química , Biotina/química , Materiais Revestidos Biocompatíveis/síntese química , Peroxidase do Rábano Silvestre/química , Imunoensaio/métodos , Nanopartículas de Magnetita/química , Adsorção , Enzimas Imobilizadas/química , Nanopartículas de Magnetita/ultraestrutura , Tamanho da Partícula , Propriedades de Superfície
10.
J Sci Food Agric ; 94(15): 3195-200, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24652764

RESUMO

BACKGROUND: Some hydrolyzed peptides derived from food proteins possess antioxidant and anti-fatigue activities. In this study, egg white protein powder (EWPP) was hydrolyzed with pepsin for various times, and four peptide fractions were separated from the hydrolysates by ultrafiltration. The antioxidant activity of the four peptide fractions was determined. The peptide fraction with the strongest antioxidant activity was used to evaluate its anti-fatigue effect and probable mechanisms. RESULTS: The egg white peptides (EWPs) fraction with molecular weight 2-5 kDa (named EWPs2) showed stronger antioxidant activity than the other peptide fractions (P < 0.05). The swimming time to exhaustion of mice administered EWPs2 was longer (P < 0.05) than that of the control group. EWPs2 increased the levels of blood glucose (by 28.4-42.2%), muscle glycogen (by 6.4-10.6%) and liver glycogen (by 10.7-23.8%) and significantly decreased the levels of lactic acid in muscle and urea nitrogen in blood (P < 0.05). CONCLUSION: Among the four peptide fractions, EWPs2 possessed the strongest antioxidant activity and exhibited an anti-fatigue effect. The experimental data could clarify partially the anti-fatigue mechanisms of EWPs and provide an important basis for developing EWPs as safe and natural antioxidants and anti-fatigue agents for wide use.


Assuntos
Antioxidantes/farmacologia , Proteínas do Ovo/química , Proteínas do Ovo/metabolismo , Fadiga Muscular/efeitos dos fármacos , Pepsina A/metabolismo , Peptídeos/farmacologia , Aminoácidos/análise , Animais , Glicemia/análise , Sequestradores de Radicais Livres , Glicogênio/análise , Hidrólise , Ácido Láctico/análise , Peroxidação de Lipídeos/efeitos dos fármacos , Glicogênio Hepático/análise , Masculino , Camundongos , Peso Molecular , Músculo Esquelético/química , Peptídeos/isolamento & purificação , Peptídeos/metabolismo , Natação , Ultrafiltração
11.
Food Chem X ; 22: 101452, 2024 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-38808161

RESUMO

The purpose of this study was to compare the structural and functional of protein from yak milk residue, which collected from different elevations (MRP1 and MRP2) in Tibet, as well as their potential for enhancing the quality of non-fat yogurt. The results showed that MRP1 exhibited higher levels of ß-sheet, turbidity, particle size, and gel properties. MRP2 had better flexibility, emulsification, foaming, water/oil absorption capacity. The addition of MRP1 (3%) could improve texture and sensory properties of yogurt. Although MRP2 yogurt had higher hardness, gumminess, chewiness and water holding capacity, poor mouthfeel. Rheological test showed that MRPs yogurt exhibited typical gel-like and shear-thinning behavior. Moreover, the fortification of non-fat yogurts with MRP1 brought the formation of larger protein clusters with a more tightly knit network of smaller pores. These results indicate that MRP1 can be used as a fat substitute to improve the quality of non-fat yogurt.

12.
Food Chem X ; 21: 101166, 2024 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-38322764

RESUMO

Efficient and comprehensive analysis of lipid profiles in yak ghee samples collected from different elevations is crucial for optimal utilization of these resources. Unfortunately, such research is relatively rare. Yak ghee collected from three locations at different altitudes (S2: 2986 m; S5: 3671 m; S6: 4508 m) were analyzed by quantitative lipidomic. Our analysis identified a total of 176 lipids, and 147 s lipid of them were upregulated and 29 lipids were downregulated. These lipids have the potential to serve as biomarkers for distinguishing yak ghee from different altitudes. Notably, S2 exhibited higher levels of fatty acids (21:1) and branched fatty acid esters of hydroxy fatty acids (14:0/18:0), while S5 showed increased levels of phosphatidylserine (O-20:0/19:1) and glycerophosphoric acid (19:0/22:1). S6 displayed higher levels of triacylglycerol (17:0/20:5/22:3), ceramide alpha-hydroxy fatty acid-sphingosine (d17:3/34:2), and acyl glucosylceramides (16:0-18:0-18:1). Yak ghee exhibited a high content of neutralizing glycerophospholipids and various functional lipids, including sphingolipids and 21 newly discovered functional lipids. Our findings provide insights into quantitative changes in yak ghee lipids during different altitudes, development of yak ghee products, and screening of potential biomarkers.

13.
Redox Biol ; 75: 103252, 2024 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-38925040

RESUMO

Pulmonary vascular remodeling and inflammation play an important role in the hypoxic-induced lung diseases. Our previous investigations showed that peptide from yak milk residues could alleviate inflammation. In this study, our results suggest that peptide (LV) from yak milk residues peptide had protective effect of lung in the animal models of hypoxic-induced lung injury. LV Gavage could improve pulmonary vascular remodeling in the lung tissues of hypoxic mice. A comprehensive analysis of metabolomics and transcriptomics revealed that 5-KETE, 8,9-EET, and 6-keto-prostaglandin F1a might be potential targets to prevent lung injury in the hypoxic mice. These metabolites can be regulated by MAPK/VEGF and inflammatory pathways. Our data indicated that LV treatment could inhibit apoptosis and inflammation via Nrf2/NF-κB/MAPK/PHD-2 pathway and protected hypoxic-induced lung epithelial cells injury. Taken together, our results suggest that LV provides a novel therapeutic clue for the prevention of hypoxia-induced lung injury and inflammation-related lung diseases.

14.
Cancer Lett ; 585: 216667, 2024 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-38280479

RESUMO

The activation of YAP/TAZ, a pair of paralogs of transcriptional coactivators, initiates a dysregulated transcription program, which is a key feature of human cancer cells. However, it is not fully understood how YAP/TAZ promote dysregulated transcription for tumor progression. In this study, we employed the BioID method to identify the interactome of YAP/TAZ and discovered that YAP/TAZ interact with multiple components of SRCAP complex, a finding that was further validated through endogenous and exogenous co-immunoprecipitation, as well as immunofluorescence experiments. CUT&Tag analysis revealed that SRCAP complex facilitates the deposition of histone variant H2A.Z at target promoters. The depletion of SRCAP complex resulted in a decrease in H2A.Z occupancy and the oncogenic transcription of YAP/TAZ target genes. Additionally, the blockade of SRCAP complex suppressed YAP-driven tumor growth. In a genetically engineered lung adenocarcinoma mouse model and non-small cell lung cancer patients, SRCAP complex and H2A.Z deposition were found to be upregulated. This upregulation was statistically correlated with YAP expression, pathological stages, and poor survival in lung cancer patients. Together, our study uncovers that SRCAP complex plays a critical role in YAP/TAZ oncogenic transcription by coordinating H2A.Z deposition during cancer progression, providing potential targets for cancer diagnosis and prevention.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Animais , Camundongos , Humanos , Neoplasias Pulmonares/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Transdução de Sinais/genética , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas de Sinalização YAP , Histonas/metabolismo , Fosfoproteínas/genética , Fosfoproteínas/metabolismo , Adenosina Trifosfatases/metabolismo
15.
ACS Nano ; 17(13): 12915-12932, 2023 07 11.
Artigo em Inglês | MEDLINE | ID: mdl-37352467

RESUMO

Pancreatic ductal adenocarcinoma (PDAC) is an abysmal disease refractory to most standard therapies. Irreversible electroporation (IRE) is a local ablative technique for the clinical treatment of solid tumors, including locally advanced and unresectable PDAC, by intratumorally delivering high-intensity electric pulses to permanently disrupt cell membranes and induce cell death. But the distribution of electric field is uneven within the tumor, and in some regions, tumor cells only experience temporary perturbation to their cell membrane, a phenomenon denoted as reversible electroporation (RE). These tumor cells may survive and therefore are the main culprit of tumor relapse after IRE. We herein showed that RE, although not killing tumor cells, induced DNA double-strand breaks and activated DNA damage repair (DDR) responses. Using reactive oxygen species-sensitive polymeric micelles coloaded with Olaparib, an inhibitor of poly(ADP-ribose) polymerase (PARP), and AZD0156, an inhibitor of ataxia telangiectasia mutated (ATM), the resultant nanoformulation (M-TK-OA) disrupted both homologous recombination and nonhomologous end joining signaling of the DDR response and impaired colony formation in pancreatic cancer cells after RE. The combination of IRE and M-TK-OA significantly prolonged animal survival in both subcutaneous and orthotopic murine PDAC models and elicited CD8+ T cell-mediated antitumor immunity with a sustained antitumor memory. The efficacy of combined IRE and M-TK-OA treatments was partially attributed to the activation of cyclic GMP-AMP synthase-stimulator of interferon genes innate immune responses. Our study suggests that dual inhibition of PARP and ATM with nanomedicine is a promising strategy to enhance the pancreatic cancer response to IRE.


Assuntos
Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Animais , Camundongos , Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia , Linhagem Celular Tumoral , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/patologia , Carcinoma Ductal Pancreático/tratamento farmacológico , Carcinoma Ductal Pancreático/patologia , Poli(ADP-Ribose) Polimerases/genética , Quebras de DNA de Cadeia Dupla , Eletroporação , Dano ao DNA , Neoplasias Pancreáticas
16.
Guang Pu Xue Yu Guang Pu Fen Xi ; 32(3): 719-22, 2012 Mar.
Artigo em Zh | MEDLINE | ID: mdl-22582640

RESUMO

The interaction between riboflavin and egg white riboflavin binding protein (RBP) was investigated using fluorescence spectroscopy. The binding mode, binding constants, thermodynamic parameters between riboflavin and RBP and energy transfer were studied. The experimental results showed that riboflavin has the ability to quench the intrinsic fluorescence of RBP because of a complex formed, and the quenching mechanism is static quenching. The binding constants were 5.35 x 10(8), 1.54 x 10(8), 0.56 x 10(8) L x mol(-1) at 298, 308 and 318 K, respectively. The thermodynamic parameters were calculated, which suggested hydrogen bonds and Van der Waals played a major role in the interaction. The distance and efficiency of energy transfer between riboflavin and RBP were 0.70 nm and 0.39, respectively, based on the theory of Forster nonradiative energy transfer. Furthermore, the synchronous fluorescence spectroscopy was utilized to investigate the conformational transformation.


Assuntos
Proteínas de Membrana Transportadoras/química , Riboflavina/química , Espectrometria de Fluorescência , Transferência de Energia , Fluorescência , Ligação Proteica , Termodinâmica
17.
Int J Biol Macromol ; 217: 88-95, 2022 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-35817234

RESUMO

Native broken-rice starch was used to create starch nanoparticles (StNPs) with particle sizes ranging from 100 nm to 800 nm. The fluorescent isothiocyanate poly-l-lysine StNPs (FITC-PLL-StNPs) were created in two steps. First, the StNPs were electrostatically modified by poly-l-lysine (PLL) molecules rich in amino acids. Second, fluorescein isothiocyanate reacted with some amino groups on PLL molecules (FITC). Fluorescence spectrophotometry was used to determine the degree of substitution (DS) and fluorescent properties of fluorescent starches. The study found that FITC-PLL-StNP-200 has higher fluorescence stability, more phagocytic cells, and a better and clearer fluorescence detecting effect than FITC-PLL-St, FITC-PLL-StNP-100, FITC-PLL-StNP-400, and FITC-PLL-StNP-800. The biological evaluation results showed that FITC-PLL-StNP-200 did not affect the viability of HeLa cells at the lysosome labeling concentration. These findings suggest that FITC-PLL-StNP-200 has strong and stable fluorescence, indicating that FITC-PLL-StNP-200 can be used as a fluorescent probe and lysosome marker in a variety of applications, particularly in biomedicine.


Assuntos
Nanopartículas , Oryza , Fluoresceína-5-Isotiocianato , Corantes Fluorescentes , Células HeLa , Humanos , Nanopartículas/química , Polilisina/química , Amido/química
18.
Adv Sci (Weinh) ; 9(10): e2105240, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35128843

RESUMO

Pancreatic cancer is a deadly disease with little response to standard therapies. Irreversible electroporation (IRE) has emerged as a novel ablative technique for the clinical treatment of pancreatic cancer. Combinations of IRE and immunotherapies, including anti-programmed death 1 (αPD1) immune checkpoint blockade, have shown promising efficacy in both preclinical and clinical studies. However, tumor recurrence remains an obstacle that needs to be overcome. It herein is shown that IRE induces a substantial infiltration of neutrophils into pancreatic tumors. These neutrophils are then polarized into a protumor phenotype by immunosuppressive cues, in particular transforming growth factor ß (TGF-ß). Using glutathione-responsive degradable mesoporous silica nanoparticles loaded with SB525334, an inhibitor of TGF-ß1 receptor, it is demonstrated that local inhibition of TGF-ß within the tumor microenvironment promotes neutrophil polarization into an antitumor phenotype, enhances pancreatic cancer response to combined IRE and αPD1 therapy, and induces long-term antitumor memory. The therapeutic efficacy is also attributed to tumor infiltration by CD8+ cytotoxic T cells, depletion of regulatory T cells, and maturation of antigen-presenting dendritic cells. Thus, modulating neutrophil polarization with nanomedicine is a promising strategy for treating pancreatic cancer.


Assuntos
Imunoterapia , Neutrófilos , Neoplasias Pancreáticas , Fator de Crescimento Transformador beta , Linfócitos T CD8-Positivos , Eletroporação/métodos , Humanos , Neoplasias Pancreáticas/terapia , Fator de Crescimento Transformador beta/antagonistas & inibidores , Microambiente Tumoral
19.
Guang Pu Xue Yu Guang Pu Fen Xi ; 31(12): 3319-22, 2011 Dec.
Artigo em Zh | MEDLINE | ID: mdl-22295786

RESUMO

The effect of S-configuration transformation on the microstructure of ovalbumin was studied by CD spectra, XRD spectra, ANS fluorescence probe emission spectra and UV absorption spectra. CD spectra was used to examine the changes in the secondary structure of the ovalbumin during S-ovalbumin information process. When the induction time was prolonged, the mutual transformation between alpha-helix, beta-sheet, beta-turn and the random coil was observed, and the orderliness of the secondary structure was increased with alpha-helix decreasing slightly and beta-sheet increasing correspondingly. XRD spectra analysis showed that the crystal structure content of the ovalbumin increased with prolonging the induction time and the largest data was observed at 72 h, indicating that the orderliness of the secondary structure was increased. The results were similar to CD spectra analysis. The ANS fluorescence probe emission spectra analysis demonstrated that S-configuration transformation induced an increase in surface hydrophobicity with prolonging the induction time, and the largest data was also observed at 72 h. In addition, UV absorption spectra analysis indicated that S-configuration transformation resulted in a decrease in the UV-absorption maximum value with prolonging the induction time, indicating that the aromatic amino acid was buried in the molecular interior. The results indicated that the changes in the microstructure of ovalbumin were relevant to S-configuration transformation.


Assuntos
Ovalbumina/química , Espectrometria de Fluorescência , Corantes Fluorescentes , Interações Hidrofóbicas e Hidrofílicas , Estrutura Secundária de Proteína
20.
STAR Protoc ; 2(2): 100595, 2021 06 18.
Artigo em Inglês | MEDLINE | ID: mdl-34169289

RESUMO

Anti-PD-1/PD-L1 therapy shows long-term effects in many cancer types, but resistance and relapse remain the main limitations of this therapy. Here, we describe a protocol to evaluate the tumor response to immunotherapy in a mouse lung cancer model. The protocol includes the establishment of the lung cancer mouse model, anti-PD-1 treatment, tumor-infiltrating lymphocyte isolation, immunofluorescence, and flow cytometry analysis. This protocol can also be applied to other cancer types and immunotherapies. For complete details on the use and execution of this protocol, please refer to Yu et al. (2021).


Assuntos
Adenocarcinoma de Pulmão/terapia , Neoplasias Pulmonares/terapia , Adenocarcinoma de Pulmão/imunologia , Animais , Separação Celular , Modelos Animais de Doenças , Citometria de Fluxo , Xenoenxertos , Neoplasias Pulmonares/imunologia , Linfócitos do Interstício Tumoral/imunologia , Masculino , Camundongos , Resultado do Tratamento
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