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1.
Food Funct ; 14(24): 10747-10758, 2023 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-37975749

RESUMO

Herein, we studied the in vitro-simulated intestinal flora fermentation of Porphyra haitanensis polysaccharides (PHPs) with microwave, ultrasonic, ultra-high pressure-assisted extraction and the protective effect of their fermented products against HT-29 human colon cancer cells. The results showed that PHPs were largely degraded at the 18 h stage of ascending colon fermentation, further greatly increasing the contents of reducing sugars and short-chain fatty acids (p < 0.05). Particularly, the PHPs subjected to ultra-high pressure-assisted extraction (UHP-PHP) showed the highest reducing sugar content of 1.68 ± 0.01 mg mL-1 and butyric acid content of 410.77 ± 7.99 mmol mL-1. Moreover, UHP-PHP showed a better effect in increasing the ratio of Bacteroidetes/Firmicutes and decreasing the abundance of Proteobacteria and Escherichia coli. PHPs could protect against HT-29 cells by increasing the ROS levels in a concentration-dependent manner, especially UHP-PHP fermented in a descending colon for 24 h. This was related to the up-regulated apoptosis-related genes (Bax and Bak), down-regulated protein expression of Bcl-2 and activation of the p-AKT protein, thereby promoting the apoptosis of HT-29 cells. Our results can facilitate the modification of PHPs and their practical application in the development of intestinal health improving products.


Assuntos
Neoplasias do Colo , Microbioma Gastrointestinal , Porphyra , Humanos , Células HT29 , Fermentação , Polissacarídeos/farmacologia , Polissacarídeos/metabolismo , Neoplasias do Colo/tratamento farmacológico , Ácido Butírico
2.
Neurooncol Adv ; 5(1): vdad095, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37781087

RESUMO

Background: Medulloblastoma is the most common malignant pediatric brain tumor, and leptomeningeal dissemination (LMD) of medulloblastoma both portends a poorer prognosis at diagnosis and is incurable at recurrence. The biological mechanisms underlying LMD are unclear. The Abelson (ABL) tyrosine kinase family members, ABL1 and ABL2, have been implicated in cancer cell migration, invasion, adhesion, metastasis, and chemotherapy resistance, and are upstream mediators of the oncogene c-MYC in fibroblasts and lung cancer cells. However, their role in medulloblastoma has not yet been explored. The purpose of this work was to elucidate the role of ABL1/2 in medulloblastoma LMD. Methods: ABL1 and ABL2 mRNA expression of patient specimens was analyzed. shRNA knockdowns of ABL1/2 and pharmacologic inhibition of ABL1/2 were used for in vitro and in vivo analyses of medulloblastoma LMD. RNA sequencing of ABL1/2 genetic knockdown versus scrambled control medulloblastoma was completed. Results: ABL1/2 mRNA is highly expressed in human medulloblastoma and pharmacologic inhibition of ABL kinases resulted in cytotoxicity. Knockdown of ABL1/2 resulted in decreased adhesion of medulloblastoma cells to the extracellular matrix protein, vitronectin (P = .0013), and significantly decreased tumor burden in a mouse model of medulloblastoma LMD with improved overall survival (P = .0044). Furthermore, both pharmacologic inhibition of ABL1/2 and ABL1/2 knockdown resulted in decreased expression of c-MYC, identifying a putative signaling pathway, and genes/pathways related to oncogenesis and neurodevelopment were differentially expressed between ABL1/2 knockdown and control medulloblastoma cells. Conclusions: ABL1 and ABL2 have potential roles in medulloblastoma LMD upstream of c-MYC expression.

3.
J Transl Med ; 21(1): 712, 2023 10 10.
Artigo em Inglês | MEDLINE | ID: mdl-37817192

RESUMO

Maintenance of internal homeostasis is a sophisticated process, during which almost all organs get involved. Liver plays a central role in metabolism and involves in endocrine, immunity, detoxification and storage, and therefore it communicates with distant organs through such mechanisms to regulate pathophysiological processes. Dysfunctional liver is often accompanied by pathological phenotypes of distant organs, including the eyes. Many reviews have focused on crosstalk between the liver and gut, the liver and brain, the liver and heart, the liver and kidney, but with no attention paid to the liver and eyes. In this review, we summarized intimate connections between the liver and the eyes from three aspects. Epidemiologically, we suggest liver-related, potential, protective and risk factors for typical eye disease as well as eye indicators connected with liver status. For molecular mechanism aspect, we elaborate their inter-organ crosstalk from metabolism (glucose, lipid, proteins, vitamin, and mineral), detoxification (ammonia and bilirubin), and immunity (complement and inflammation regulation) aspect. In clinical application part, we emphasize the latest advances in utilizing the liver-eye axis in disease diagnosis and therapy, involving artificial intelligence-deep learning-based novel diagnostic tools for detecting liver disease and adeno-associated viral vector-based gene therapy method for curing blinding eye disease. We aim to focus on and provide novel insights into liver and eyes communications and help resolve existed clinically significant issues.


Assuntos
Oftalmopatias , Hepatopatias , Humanos , Inteligência Artificial , Inflamação
4.
Int J Biol Macromol ; 252: 126401, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37597638

RESUMO

κ-Carrageenase can degrade κ-carrageenan to produce bioactive κ-carrageenan oligosaccharides (KCOs) that have potential applications in pharmaceutical, food, agricultural, and cosmetics industries. Immobilized enzymes gain their popularity due to their good reusability, enhanced stability, and tunability. In this study, the previously characterized catalytic domain of Pseudoalteromonas purpurea κ-carrageenase was covalently immobilized on the synthesized amine-modified zeolitic imidazolate framework-8 nanoparticles with the formation of cross-linked enzyme aggregates, and the immobilized κ-carrageenase was further characterized. The immobilized κ-carrageenase demonstrated excellent pH stability and good reusability, and exhibited higher optimal reaction temperature, better thermostability, and extended storage stability compared with the free enzyme. The KCOs produced by the immobilized κ-carrageenase could significantly decrease the TC, TG, and LDL-C levels in HepG2 cells, increase the HDL-C level in HepG2 cells, and reduce the free fatty acids level in Caco-2 cells. Biochemical assays showed that the KCOs could activate AMPK activity, increase the ratios of p-AMPK/AMPK and p-ACC/ACC, and downregulate the expression of the lipid metabolism related proteins including SREBP1 and HMGCR in the hyperlipidemic HepG2 cells. This study provides a novel and effective method for immobilization of κ-carrageenase, and the KCOs produced by the immobilized enzyme could be a potential therapeutic agent to prevent hyperlipidemia.


Assuntos
Proteínas Quinases Ativadas por AMP , Proteínas de Bactérias , Humanos , Carragenina/química , Células CACO-2 , Células Hep G2 , Proteínas de Bactérias/química , Glicosídeo Hidrolases/química , Oligossacarídeos/química , Enzimas Imobilizadas
5.
Cancers (Basel) ; 15(15)2023 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-37568717

RESUMO

Glioblastoma (GBM) is the most common malignant primary brain tumor in adults. Despite standard therapies, including resection and chemoradiation, recurrence is virtually inevitable. Current treatment for recurrent glioblastoma (rGBM) is rapidly evolving, and emerging therapies aimed at targeting primary GBM are often first tested in rGBM to demonstrate safety and feasibility, which, in recent years, has primarily been in the form of immunotherapy. The purpose of this review is to highlight progress in clinical trials of immunotherapy for rGBM, including immune checkpoint blockade, oncolytic virotherapy, chimeric antigen receptor (CAR) T-cell therapy, cancer vaccine and immunotoxins. Three independent reviewers covered literature, published between the years 2000 and 2022, in various online databases. In general, the efficacy of immunotherapy in rGBM remains uncertain, and is limited to subsets/small cohorts of patients, despite demonstrating feasibility in early-stage clinical trials. However, considerable progress has been made in understanding the mechanisms that may preclude rGBM patients from responding to immunotherapy, as well as in developing new approaches/combination strategies that may inspire optimism for the utility of immunotherapy in this devastating disease. Continued trials are necessary to further assess the best therapeutic avenues and ascertain which treatments might benefit each patient individually.

6.
Invest Ophthalmol Vis Sci ; 64(4): 12, 2023 04 03.
Artigo em Inglês | MEDLINE | ID: mdl-37043340

RESUMO

Purpose: The proliferation, migration, and epithelial-mesenchymal transition (EMT) of lens epithelial cells (LECs) are believed to be the pathological mechanisms underlying anterior subcapsular cataract (ASC). Bone morphogenetic proteins (BMPs) inhibit transforming growth factor-beta (TGF-ß)-induced fibrosis in the lens. Herein, we aimed to further clarify the roles of BMP-4/BMP-7 in the progression and the underlying mechanisms of fibrotic cataract. Methods: BMP-4/BMP-7, TGF-ß2, jagged-1 peptide, or DAPT were applied in a mouse injury-induced ASC model and in the human LEC cell line SRA01/04. The volume of opacity was examined by a slit lamp and determined by lens anterior capsule whole-mount immunofluorescence. Global gene expression changes were assessed by RNA sequencing, and the levels of individual mRNAs were validated by real-time PCR. Protein expression was determined by the Simple Western sample dilution buffer. Cell proliferation was examined by CCK8 and EdU assays, and cell migration was measured by Transwell and wound healing assays. Results: Anterior chamber injection of BMP-4/BMP-7 significantly suppressed subcapsular opacification formation. RNA sequencing of the mouse ASC model identified the Notch pathway as a potential mechanism involved in BMP-mediated inhibition of ASC. Consistently, BMP-4/BMP-7 selectively suppressed Notch1 and Notch3 and their downstream genes, including Hes and Hey. BMP-4/BMP-7 or DAPT suppressed cell proliferation by inducing G1 cell cycle arrest. BMP-4/BMP-7 also inhibited TGF-ß2-induced cell migration and EMT by modulating the Notch pathway. Conclusions: BMP-4/BMP-7 attenuated ASC by inhibiting proliferation, migration, and EMT of LECs via modulation of the Notch pathway, thereby providing a new avenue for ASC treatment.


Assuntos
Opacificação da Cápsula , Catarata , Cristalino , Camundongos , Animais , Humanos , Fator de Crescimento Transformador beta2/farmacologia , Transição Epitelial-Mesenquimal , Proteína Morfogenética Óssea 7/farmacologia , Inibidores da Agregação Plaquetária/farmacologia , Catarata/metabolismo , Cristalino/metabolismo , Transdução de Sinais , Proliferação de Células , Movimento Celular , Células Epiteliais/metabolismo , Opacificação da Cápsula/patologia
7.
J Immunother Cancer ; 11(4)2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-37072349

RESUMO

BACKGROUND: Antitumor mechanisms of CD4+ T cells remain crudely defined, and means to effectively harness CD4+ T-cell help for cancer immunotherapy are lacking. Pre-existing memory CD4+ T cells hold potential to be leveraged for this purpose. Moreover, the role of pre-existing immunity in virotherapy, particularly recombinant poliovirus immunotherapy where childhood polio vaccine specific immunity is ubiquitous, remains unclear. Here we tested the hypothesis that childhood vaccine-specific memory T cells mediate antitumor immunotherapy and contribute to the antitumor efficacy of polio virotherapy. METHODS: The impact of polio immunization on polio virotherapy, and the antitumor effects of polio and tetanus recall were tested in syngeneic murine melanoma and breast cancer models. CD8+ T-cell and B-cell knockout, CD4+ T-cell depletion, CD4+ T-cell adoptive transfer, CD40L blockade, assessments of antitumor T-cell immunity, and eosinophil depletion defined antitumor mechanisms of recall antigens. Pan-cancer transcriptome data sets and polio virotherapy clinical trial correlates were used to assess the relevance of these findings in humans. RESULTS: Prior vaccination against poliovirus substantially bolstered the antitumor efficacy of polio virotherapy in mice, and intratumor recall of poliovirus or tetanus immunity delayed tumor growth. Intratumor recall antigens augmented antitumor T-cell function, caused marked tumor infiltration of type 2 innate lymphoid cells and eosinophils, and decreased proportions of regulatory T cells (Tregs). Antitumor effects of recall antigens were mediated by CD4+ T cells, limited by B cells, independent of CD40L, and dependent on eosinophils and CD8+ T cells. An inverse relationship between eosinophil and Treg signatures was observed across The Cancer Genome Atlas (TCGA) cancer types, and eosinophil depletion prevented Treg reductions after polio recall. Pretreatment polio neutralizing antibody titers were higher in patients living longer, and eosinophil levels increased in the majority of patients, after polio virotherapy. CONCLUSION: Pre-existing anti-polio immunity contributes to the antitumor efficacy of polio virotherapy. This work defines cancer immunotherapy potential of childhood vaccines, reveals their utility to engage CD4+ T-cell help for antitumor CD8+ T cells, and implicates eosinophils as antitumor effectors of CD4+ T cells.


Assuntos
Tétano , Vacinas , Camundongos , Humanos , Animais , Linfócitos T CD8-Positivos , Eosinófilos , Ligante de CD40 , Imunidade Inata , Linfócitos , Linfócitos T Reguladores
8.
Neuro Oncol ; 25(9): 1631-1643, 2023 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-36864784

RESUMO

BACKGROUND: Malignant gliomas commandeer dense inflammatory infiltrates with glioma-associated macrophages and microglia (GAMM) promoting immune suppression, evasion, and tumor progression. Like all cells in the mononuclear phagocytic system, GAMM constitutively express the poliovirus receptor, CD155. Besides myeloid cells, CD155 is widely upregulated in the neoplastic compartment of malignant gliomas. Intratumor treatment with the highly attenuated rhino:poliovirus chimera, PVSRIPO, yielded long-term survival with durable radiographic responses in patients with recurrent glioblastoma (Desjardins et al. New England Journal of Medicine, 2018). This scenario raises questions about the contributions of myeloid versus neoplastic cells to polio virotherapy of malignant gliomas. METHODS: We investigated PVSRIPO immunotherapy in immunocompetent mouse brain tumor models with blinded, board-certified neuropathologist review, a range of neuropathological, immunohistochemical, and immunofluorescence analyses, and RNAseq of the tumor region. RESULTS: PVSRIPO treatment caused intense engagement of the GAMM infiltrate associated with substantial, but transient tumor regression. This was accompanied by marked microglia activation and proliferation in normal brain surrounding the tumor, in the ipsilateral hemisphere and extending into the contralateral hemisphere. There was no evidence for lytic infection of malignant cells. PVSRIPO-instigated microglia activation occurred against a backdrop of sustained innate antiviral inflammation, associated with induction of the Programmed Cell Death Ligand 1 (PD-L1) immune checkpoint on GAMM. Combining PVSRIPO with PD1/PD-L1 blockade led to durable remissions. CONCLUSIONS: Our work implicates GAMM as active drivers of PVSRIPO-induced antitumor inflammation and reveals profound and widespread neuroinflammatory activation of the brain-resident myeloid compartment by PVSRIPO.


Assuntos
Neoplasias Encefálicas , Glioma , Terapia Viral Oncolítica , Poliomielite , Animais , Camundongos , Microglia/metabolismo , Antígeno B7-H1 , Glioma/terapia , Neoplasias Encefálicas/metabolismo , Poliomielite/terapia , Inflamação
9.
Food Funct ; 14(2): 1133-1147, 2023 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-36594623

RESUMO

A combination of polysaccharides and tea polyphenols can enhance immune activity synergistically, depending on the type and structure of polysaccharides, but the mechanism remains unknown. This study is aimed to investigate the regulating effects of different seaweed polysaccharide (ι-carrageenan, agarose) and tea polyphenol blends on intestinal flora and intestinal inflammation using an in vitro ascending-transverse-descending colon fermentation system and RAW264.7 cell model. The results showed that seaweed polysaccharides in the presence of tea polyphenol were almost completely degraded at transverse colon fermentation for 36 h. Agarose significantly enhanced the butyric acid production content by increasing the abundance of Lachnospiraceae, whereas agarose and tea polyphenol blends did not have a synergistic effect. On the contrary, ι-carrageenan and tea polyphenol blends synergistically increased the abundance of beneficial bacteria (e.g., Bacteroidetes and Bifidobacterium) and promoted the production of short-chain fatty acids (SCFAs), such as isobutyric acid. Such changes tended to alter the impacts of different seaweed polysaccharides and tea polyphenol blends on intestinal inflammation. Among them, ι-carrageenan and tea polyphenol blends were the most effective in inhibiting lipopolysaccharide-induced NO, ROS, IL-6, and TNF-α production in RAW264.7 cells, indicating the alleviated intestinal inflammation. The results suggest that the seaweed polysaccharide and tea polyphenol blends have prebiotic potential and can benefit intestinal health.


Assuntos
Microbioma Gastrointestinal , Alga Marinha , Humanos , Alga Marinha/metabolismo , Fermentação , Carragenina , Sefarose , Polifenóis/farmacologia , Polissacarídeos/farmacologia , Chá/química , Inflamação
10.
Anal Chem ; 95(8): 4104-4112, 2023 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-36688529

RESUMO

Significant progress has been made in nanomaterial-modified electrodes for highly efficient electroanalysis of arsenic(III) (As(III)). However, the modifiers prepared using some physical methods may easily fall off, and active sites are not uniform, causing the potential instability of the modified electrode. This work first reports a promising practical strategy without any modifiers via utilizing only soluble Fe3+ as a trigger to detect trace-level As(III) in natural water. This method reaches an actual detection limit of 1 ppb on bare glassy carbon electrodes and a sensitivity of 0.296 µA ppb-1 with excellent stability. Kinetic simulations and experimental evidence confirm the codeposition mechanism that Fe3+ is preferentially deposited as Fe0, which are active sites to adsorb As(III) and H+ on the electrode surface. This facilitates the formation of AsH3, which could further react with Fe2+ to produce more As0 and Fe0. Meanwhile, the produced Fe0 can also accelerate the efficient enrichment of As0. Remarkably, the proposed sensing mechanism is a general rule for the electroanalysis of As(III) that is triggered by iron group ions (Fe2+, Fe3+, Co2+, and Ni2+). The interference analysis of coexisting ions (Cu2+, Zn2+, Al3+, Hg2+, Cd2+, Pb2+, SO42-, NO3-, Cl-, and F-) indicates that only Cu2+, Pb2+, and F- showed inhibitory effects on As(III) due to the competition of active sites. Surprisingly, adding iron power effectively eliminates the interference of Cu2+ in natural water, achieving a higher sensitivity for 1-15 ppb As(III) (0.487 µA ppb-1). This study provides effective solutions to overcome the potential instability of modified electrodes and offers a practical sensing platform for analyzing other heavy-metal anions.

11.
J Am Chem Soc ; 143(40): 16377-16382, 2021 10 13.
Artigo em Inglês | MEDLINE | ID: mdl-34596400

RESUMO

The targeted degradation of membrane proteins would afford an attractive and general strategy for treating various diseases that remain difficult with the current proteolysis-targeting chimera (PROTAC) methodology. We herein report a covalent nanobody-based PROTAC strategy, termed GlueTAC, for targeted membrane protein degradation with high specificity and efficiency. We first established a mass-spectrometry-based screening platform for the rapid development of a covalent nanobody (GlueBody) that allowed proximity-enabled cross-linking with surface antigens on cancer cells. By conjugation with a cell-penetrating peptide and a lysosomal-sorting sequence, the resulting GlueTAC chimera triggered the internalization and degradation of programmed death-ligand 1 (PD-L1), which provides a new avenue to target and degrade cell-surface proteins.


Assuntos
Proteólise
12.
Nat Commun ; 12(1): 1858, 2021 03 25.
Artigo em Inglês | MEDLINE | ID: mdl-33767151

RESUMO

Activating intra-tumor innate immunity might enhance tumor immune surveillance. Virotherapy is proposed to achieve tumor cell killing, while indirectly activating innate immunity. Here, we report that recombinant poliovirus therapy primarily mediates antitumor immunotherapy via direct infection of non-malignant tumor microenvironment (TME) cells, independent of malignant cell lysis. Relative to other innate immune agonists, virotherapy provokes selective, TBK1-IRF3 driven innate inflammation that is associated with sustained type-I/III interferon (IFN) release. Despite priming equivalent antitumor T cell quantities, MDA5-orchestrated TBK1-IRF3 signaling, but not NFκB-polarized TLR activation, culminates in polyfunctional and Th1-differentiated antitumor T cell phenotypes. Recombinant type-I IFN increases tumor-localized T cell function, but does not mediate durable antitumor immunotherapy without concomitant pattern recognition receptor (PRR) signaling. Thus, virus-induced MDA5-TBK1-IRF3 signaling in the TME provides PRR-contextualized IFN responses that elicit functional antitumor T cell immunity. TBK1-IRF3 innate signal transduction stimulates eventual function and differentiation of tumor-infiltrating T cells.


Assuntos
Neoplasias da Mama/terapia , Fator Regulador 3 de Interferon/imunologia , Melanoma/terapia , Terapia Viral Oncolítica , Proteínas Serina-Treonina Quinases/imunologia , Microambiente Tumoral/imunologia , Animais , Neoplasias da Mama/imunologia , Neoplasias da Mama/patologia , Linfócitos T CD8-Positivos/imunologia , Feminino , Humanos , Imunidade Inata/imunologia , Interferon Tipo I/imunologia , Helicase IFIH1 Induzida por Interferon/metabolismo , Linfócitos do Interstício Tumoral/imunologia , Melanoma/imunologia , Melanoma/patologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , NF-kappa B/metabolismo , Transdução de Sinais/imunologia , Células Th1/imunologia
13.
J Exp Bot ; 72(5): 1822-1835, 2021 02 27.
Artigo em Inglês | MEDLINE | ID: mdl-33277994

RESUMO

Plant-specific WOX family transcription factors play important roles ranging from embryogenesis to lateral organ development. The WOX1 transcription factors, which belong to the modern clade of the WOX family, are known to regulate outgrowth of the leaf blade specifically in the mediolateral axis; however, the role of WOX1 in compound leaf development remains unknown. Phylogenetic analysis of the whole WOX family in tomato (Solanum lycopersicum) indicates that there are 10 members that represent the modern, intermediate, and ancient clades. Using phylogenetic analysis and a reverse genetic approach, in this study we identified SlLAM1 in the modern clade and examined its function and tissue-specific expression pattern. We found that knocking out SlLAM1 via CRISPR/Cas9-mediated genome editing led to narrow leaves and a reduced number of secondary leaflets. Overexpression of tomato SlLAM1 could rescue the defects of the tobacco lam1 mutant. Anatomical and transcriptomic analyses demonstrated that floral organ development, fruit size, secondary leaflet initiation, and leaf complexity were altered due to loss-of-function of SlLAM1. These findings demonstrate that tomato SlLAM1 plays an important role in the regulation of secondary leaflet initiation, in addition to its conserved function in blade expansion.


Assuntos
Flores/crescimento & desenvolvimento , Folhas de Planta/crescimento & desenvolvimento , Proteínas de Plantas , Solanum lycopersicum , Regulação da Expressão Gênica de Plantas , Solanum lycopersicum/genética , Solanum lycopersicum/metabolismo , Filogenia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
14.
Small ; 16(46): e2004237, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-33107685

RESUMO

Prevention and intervention methods are urgently needed to curb the global pandemic of coronavirus disease-19 caused by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). Herein, a general pro-antigen strategy for subunit vaccine development based on the reversibly formulated receptor binding domain of SARS-CoV-2 spike protein (S-RBD) is reported. Since the poor lymph node targeting and uptake of S-RBD by antigen-presenting cells prevent effective immune responses, S-RBD protein is formulated into a reversible nanogel (S-RBD-NG), which serves as a pro-antigen with enhanced lymph node targeting and dendritic cell and macrophage accumulation. Synchronized release of S-RBD monomers from the internalized S-RBD-NG pro-antigen triggers more potent immune responses in vivo. In addition, by optimizing the adjuvant used, the potency of S-RBD-NG is further improved, which may provide a generally applicable, safer, and more effective strategy for subunit vaccine development against SARS-CoV-2 as well as other viruses.


Assuntos
Antígenos Virais/imunologia , COVID-19/imunologia , COVID-19/prevenção & controle , Imunidade , Nanogéis/química , SARS-CoV-2/imunologia , Glicoproteína da Espícula de Coronavírus/metabolismo , Animais , COVID-19/virologia , Linhagem Celular , Células Dendríticas/metabolismo , Imunização , Linfonodos/imunologia , Macrófagos/metabolismo , Camundongos , Nanogéis/ultraestrutura , Testes de Neutralização , Domínios Proteicos , Glicoproteína da Espícula de Coronavírus/química
15.
ACS Omega ; 5(18): 10415-10422, 2020 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-32426598

RESUMO

The application of disulfiram can be traced back to the 1920s, from when it was utilized to facilitate alcohol abstinence by producing allergic reactions toward alcohol. In previous research, combination of disulfiram and copper ions has demonstrated significant anti-tumor activity. However, both disulfiram and copper ions lack the ability of specific targeting to tumor tissues and may lead to a high risk of side effects, especially for copper ion, which is a kind of toxic heavy metal. Herein, a ferritin-albumin-Cu nanoparticle (FHC NP) was introduced. The nanoparticle was synthesized by first covalently cross-linking ferritin and albumin and then encapsulating the copper ions in the ferritin nanocage. The nanoparticle showed good accumulation in a tumor and when combined with disulfiram exhibited good in vitro selectivity toward cancer cells and better in vivo anti-tumor activity. Herein, the nanoparticle invented here represented a good strategy to efficaciously deliver copper ions into tumors and thus improve the therapeutic efficacy of disulfiram in tumor therapy.

16.
Nat Commun ; 11(1): 524, 2020 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-31988324

RESUMO

Viruses naturally engage innate immunity, induce antigen presentation, and mediate CD8 T cell priming against foreign antigens. Polioviruses can provide a context optimal for generating antigen-specific CD8 T cells, as they have natural tropism for dendritic cells, preeminent inducers of CD8 T cell immunity; elicit Th1-promoting inflammation; and lack interference with innate or adaptive immunity. However, notorious genetic instability and underlying neuropathogenicity has hampered poliovirus-based vector applications. Here we devised a strategy based on the polio:rhinovirus chimera PVSRIPO, devoid of viral neuropathogenicity after intracerebral inoculation in human subjects, for stable expression of exogenous antigens. PVSRIPO vectors infect, activate, and induce epitope presentation in DCs in vitro; they recruit and activate DCs with Th1-dominant cytokine profiles at the injection site in vivo. They efficiently prime tumor antigen-specific CD8 T cells in vivo, induce CD8 T cell migration to the tumor site, delay tumor growth and enhance survival in murine tumor models.


Assuntos
Linfócitos T CD8-Positivos/fisiologia , Células Dendríticas/imunologia , Poliovirus/imunologia , Animais , Vacinas Anticâncer , Vetores Genéticos/imunologia , Glioma/imunologia , Células HEK293 , Células HeLa , Humanos , Imunidade Inata , Imunoterapia/métodos , Interferon Tipo I/imunologia , Melanoma/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Poliovirus/genética
17.
J Agric Food Chem ; 67(46): 12741-12751, 2019 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-31659899

RESUMO

Tyrosinase inhibitors are important in cosmetic, medical, and food industries due to their regulation of melanin production. A tyrosinase inhibitor was purified from Camellia pollen using high-speed countercurrent chromatography and preparative high-performance liquid chromatography and was identified as caffeine by NMR and mass spectrometry. It showed strong mushroom tyrosinase inhibitory activity with an IC50 of 18.5 ± 2.31 µg/mL in a noncompetitive model. The caffeine did not interact with copper ions in the active center of the enzyme but could quench fluorescence intensity and change the secondary conformation of this tyrosinase. A molecular dynamics simulation showed that caffeine bound this tyrosinase via Lys379, Lys 376, Asp357, Glu356, Thr308, Gln307, Asp312, and Trp358, thus changing the binding sites of l-tyrosine and the loop conformation adjacent to the active center. In vitro cell model analysis revealed that caffeine exhibited significant inhibitory effects on both intracellular tyrosinase activity and melanin production of B16-F10 melanoma cells in a concentration-dependent manner. These comprehensive results suggest that caffeine is a strong tyrosinase inhibitor that has the potential to be developed as skin-whitening agents in the cosmetics and pharmaceutical industries or as antibrowning agents in the food industry.


Assuntos
Cafeína/química , Camellia/química , Inibidores Enzimáticos/química , Monofenol Mono-Oxigenase/antagonistas & inibidores , Extratos Vegetais/química , Pólen/química , Animais , Cafeína/isolamento & purificação , Linhagem Celular , Cobre , Melaninas/biossíntese , Camundongos , Simulação de Dinâmica Molecular , Preparações Clareadoras de Pele/química
18.
Chin Med J (Engl) ; 132(18): 2168-2176, 2019 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-31461731

RESUMO

BACKGROUND: Anastomotic leakage is a serious surgical complication in rectal cancer; however, effective evaluation methods for predicting anastomotic leakage individual risk in patients are not currently available. This study aimed to develop a method to evaluate the risk of leakage during surgery. METHODS: The 163 patients with rectal cancer, who had undergone anterior resection and low-ligation procedures for Doppler sonographic hemodynamic measurement from April 2011 to January 2015 in Peking University Cancer Hospital, were prospectively recruited. A predictive model was constructed based on the associations between anastomotic leakage and alterations in the anastomotic blood supply in the patients, using both univariate and multivariate statistical analyses, as well as diagnostic methodology evaluation, including Chi-square test, logistic regression model, and receiver operating characteristic curve. RESULTS: The overall anastomotic leakage incidence was 9.2% (15/163). Doppler hemodynamic parameters whose reduction was significantly associated with anastomotic leakage were peak systolic velocity, pulsatility index, and resistance index. The areas under the receiver operating characteristic curve of residual rates of peak systolic velocity, pulsatility index, and resistance index in predicting anastomotic leakage were 0.703 (95% confidence interval [CI]: 0.552-0.854), 0.729 (95% CI: 0.579-0.879), and 0.689 (95% CI: 0.522-0.856), respectively. The predictive model revealed that the patients with severely reduced blood-flow signal exhibited a significantly higher incidence rate of anastomotic leakage than those with sufficient blood supply (19.6% vs. 3.7%, P = 0.003), particularly the patients with low rectal cancer (25.9% vs. 3.9%, P = 0.007) and those receiving neoadjuvant chemoradiotherapy (32.1% vs. 3.7%, P = 0.001), independent of prophylactic ileostoma. Multivariate analysis revealed that insufficient blood supply of the anastomotic bowel was an independent risk factor for anastomotic leakage (odds ratio: 10.37, 95% CI: 2.703-42.735, P = 0.001). CONCLUSION: Based on this explorative study, Doppler sonographic hemodynamic measurement of the anastomotic bowel presented potential value in predicting anastomotic leakage.


Assuntos
Fístula Anastomótica/diagnóstico por imagem , Fístula Anastomótica/diagnóstico , Ultrassonografia Doppler/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Fístula Anastomótica/epidemiologia , Feminino , Monitorização Hemodinâmica/métodos , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Estudos Prospectivos , Neoplasias Retais/diagnóstico , Neoplasias Retais/diagnóstico por imagem , Neoplasias Retais/epidemiologia
19.
Adv Biosyst ; 3(5): e1900006, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-32627411

RESUMO

The application of ascorbate (vitamin C) for cancer therapy was first proposed in the 1970s and has shown promising results in recent clinical trials. Pharmacological doses of ascorbate selectively induce cell death in different types of cancer cells through the generation of H2 O2. However, some cancer cells are resistant to ascorbate. So increasing the sensitivity of resistant cancer cells to ascorbate has attracted considerable attention. Till now, a few attempts in nanomaterials have been made to improve the effect of ascorbate. In this study, a simple ferritin caged copper nanoparticle (Fn-Cu) significantly improves the susceptibility of ascorbate-resistant cancer cells to pharmacological ascorbate via selective inhibition of catalase activity in cancer cells, while having negligible cytotoxicity to normal cells. Remarkably, combination of Fn-Cu with a lower dose of ascorbate significantly inhibits ascorbate-resistant tumor growth and metastasis in vivo. These data demonstrate Fn-Cu has the therapeutic potential by enhancing the effect of ascorbate in cancer therapy.


Assuntos
Antineoplásicos , Ácido Ascórbico , Ferritinas , Nanopartículas , Neoplasias Experimentais , Animais , Antineoplásicos/química , Antineoplásicos/farmacologia , Ácido Ascórbico/química , Ácido Ascórbico/farmacologia , Linhagem Celular Tumoral , Preparações de Ação Retardada/química , Preparações de Ação Retardada/farmacologia , Ferritinas/química , Ferritinas/farmacologia , Células HEK293 , Humanos , Camundongos , Nanopartículas/química , Nanopartículas/uso terapêutico , Neoplasias Experimentais/tratamento farmacológico , Neoplasias Experimentais/metabolismo , Neoplasias Experimentais/patologia
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