RESUMO
Mannoproteins have traditionally been recognized as effective wine organoleptic modulators, however, ambiguous understanding of the relationship between their organoleptic functions and physiochemical characteristics often lead to inappropriate application in winemaking. To reveal the possible role the physiochemical characteristics of mannoproteins play in modulating wine color and aroma properties, three water-soluble mannoproteins (MP1, MP2, MP3) with different physiochemical characteristics have been prepared, and accelerated red wine aging, malvidin pigments formation experiments, accelerated aroma release experiments have been designed to observe their organoleptic modulating functions in this research. Results suggest that the phenolic/chromatic stability of red wines could be enhanced by MP3, probably due to its low steric hindrance potential, high reactivity, and good hydro-alcoholic stability conferred by its high Mannan/Glucan ratio (8.68), abundant hydrophobic/hydrophilic amino acids (65.29 % of total protein), and low/medium molecular weight level (30.71-57.77 kDa), respectively, which protected the phenolic compounds and promoted the formation of pyranoanthocyanins. Mannoproteins could modulate the volatility of aroma compounds by expelling or retention effects, which depended on the duration of mannoprotein application (the expelling effect was firstly observed possibly because of the significant adsorption of free H2O by MPs) and the types of mannoproteins. MP1 and MP2 were prone to retain and expel aroma compounds, respectively, probably due to their medium/high molecular weight levels (60.48-135.39 kDa) that conferred abundant interacting sites, and the high proportion of hydrophobic and hydrophilic components in MP1 (97.71 % polysaccharides of total mannoprotein, 34.58 % hydrophobic amino acids of total protein) and MP2 (97.96 % polysaccharides of total mannoprotein, 28.36 % hydrophobic amino acids of total protein) guaranteed a relatively higher interacting frequency with aroma compounds and free H2O molecules, respectively.
Assuntos
Glicoproteínas de Membrana , Odorantes , Vinho , Vinho/análise , Glicoproteínas de Membrana/metabolismo , Odorantes/análise , Cor , Mucoproteínas/química , Interações Hidrofóbicas e Hidrofílicas , Humanos , Compostos Orgânicos Voláteis/análise , Compostos Orgânicos Voláteis/químicaRESUMO
The anterior gradient protein 2 (AGR2) plays a crucial role in facilitating the formation of protein disulfide bonds within the endoplasmic reticulum (ER). Research suggests that AGR2 can function as an oncogene, with its heightened expression linked to the advancement of hepatobiliary and pancreatic cancers through invasion and metastasis. Notably, AGR2 not only serves as a pro-oncogenic agent but also as a downstream targeting protein, indirectly fostering cancer progression. This comprehensive review delves into the established functions and expression patterns of AGR2, emphasizing its pivotal role in cancer progression, particularly in hepatobiliary and pancreatic malignancies. Furthermore, AGR2 emerges as a potential cancer prognostic marker and a promising target for immunotherapy, offering novel avenues for the treatment of hepatobiliary and pancreatic cancers and enhancing patient outcomes.
Assuntos
Mucoproteínas , Proteínas Oncogênicas , Neoplasias Pancreáticas , Humanos , Mucoproteínas/metabolismo , Mucoproteínas/genética , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/terapia , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/patologia , Proteínas Oncogênicas/metabolismo , Proteínas Oncogênicas/genética , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/terapia , Neoplasias Hepáticas/patologia , Animais , Neoplasias do Sistema Biliar/genética , Neoplasias do Sistema Biliar/metabolismo , Neoplasias do Sistema Biliar/tratamento farmacológico , Neoplasias do Sistema Biliar/terapia , Neoplasias do Sistema Biliar/patologia , Regulação Neoplásica da Expressão Gênica , Biomarcadores Tumorais/metabolismo , Biomarcadores Tumorais/genéticaRESUMO
The genus Utricularia (bladderworts) species are carnivorous plants that prey on invertebrates using traps with a high-speed suction mechanism. The outer trap surface is lined by dome-shaped glands responsible for secreting water in active traps. In terminal cells of these glands, the outer wall is differentiated into several layers, and even cell wall ingrowths are covered by new cell wall layers. Due to changes in the cell wall, these glands are excellent models for studying the specialization of cell walls (microdomains). The main aim of this study was to check if different cell wall layers have a different composition. Antibodies against arabinogalactan proteins (AGPs) were used, including JIM8, JIM13, JIM14, MAC207, and JIM4. The localization of the examined compounds was determined using immunohistochemistry techniques and immunogold labeling. Differences in composition were found between the primary cell wall and the cell secondary wall in terminal gland cells. The outermost layer of the cell wall of the terminal cell, which was cuticularized, was devoid of AGPs (JIM8, JIM14). In contrast, the secondary cell wall in terminal cells was rich in AGPs. AGPs localized with the JIM13, JIM8, and JIM14 epitopes occurred in wall ingrowths of pedestal cells. Our research supports the hypothesis of water secretion by the external glands.
Assuntos
Parede Celular , Mucoproteínas , Proteínas de Plantas , Parede Celular/metabolismo , Mucoproteínas/metabolismo , Proteínas de Plantas/metabolismo , Lamiales/metabolismo , Imuno-HistoquímicaRESUMO
BACKGROUND: Oxygen concentration is a key characteristic of the fruit storage environment determining shelf life and fruit quality. The aim of the work was to identify cell wall components that are related to the response to low oxygen conditions in fruit and to determine the effects of such conditions on the ripening process. Tomato (Solanum lycopersicum) fruits at different stages of the ripening process were stored in an anoxic and hypoxic environment, at 0% and 5% oxygen concentrations, respectively. We used comprehensive and comparative methods: from microscopic immunolabelling and estimation of enzymatic activities to detailed molecular approaches. Changes in the composition of extensin, arabinogalactan proteins, rhamnogalacturonan-I, low methyl-esterified homogalacturonan, and high methyl-esterified homogalacturonan were analysed. RESULTS: In-depth molecular analyses showed that low oxygen stress affected the cell wall composition, i.e. changes in protein content, a significantly modified in situ distribution of low methyl-esterified homogalacturonan, appearance of callose deposits, disturbed native activities of ß-1,3-glucanase, endo-ß-1,4-glucanase, and guaiacol peroxidase (GPX), and disruptions in molecular parameters of single cell wall components. Taken together, the data obtained indicate that less significant changes were observed in fruit in the breaker stage than in the case of the red ripe stage. The first symptoms of changes were noted after 24 h, but only after 72 h, more crucial deviations were visible. The 5% oxygen concentration slows down the ripening process and 0% oxygen accelerates the changes taking place during ripening. CONCLUSIONS: The observed molecular reset occurring in tomato cell walls in hypoxic and anoxic conditions seems to be a result of regulatory and protective mechanisms modulating ripening processes.
Assuntos
Parede Celular , Frutas , Oxigênio , Pectinas , Proteínas de Plantas , Solanum lycopersicum , Parede Celular/metabolismo , Frutas/crescimento & desenvolvimento , Frutas/metabolismo , Solanum lycopersicum/crescimento & desenvolvimento , Solanum lycopersicum/metabolismo , Solanum lycopersicum/fisiologia , Oxigênio/metabolismo , Proteínas de Plantas/metabolismo , Pectinas/metabolismo , Mucoproteínas/metabolismoRESUMO
Gum arabic finds extensive application and typically undergoes sterilization prior to utilization in the food industry. This study explored the impact of steam sterilization temperature and duration on the physicochemical and emulsification characteristics of gum arabic, accompanied by proposed mechanisms elucidating observed effects. The results showed that when gum arabic was treated with high temperature sterilization (110 °C â¼ 140 °C), the emulsion prepared turned unstable. The interfacial tension decreased from 8.26 mN/m to 6.77 mN/m after sterilization, while the elastic modulus decreased from 23.65 mN/m to 16.16 mN/m. Moreover, the circular dichroic chromatographic results indicated that the arabinogalactan protein (AGP) structure of gum arabic was more relaxed after high temperature treatment with ß-sheets content decreased from 36.2 % to 29.8 % and random coil content increased from 41.3 % to 51.8 %. Quartz crystal microbalance with dissipation (QCM-D) results demonstrated that emulsion surface film thickness and toughness decreased after sterilization treatment of gum arabic. The study indicates that high temperature sterilization may change protein structure in gum arabic and reduce the stability of prepared emulsions.
Assuntos
Emulsões , Goma Arábica , Vapor , Goma Arábica/química , Emulsões/química , Fenômenos Químicos , Proteínas de Plantas/química , Temperatura , Mucoproteínas/química , Esterilização/métodos , Tensão SuperficialRESUMO
Species in the genus Utricularia are carnivorous plants that prey on invertebrates using traps of leaf origin. The traps are equipped with numerous different glandular trichomes. Trichomes (quadrifids) produce digestive enzymes and absorb the products of prey digestion. The main aim of this study was to determine whether arabinogalactan proteins (AGPs) occur in the cell wall ingrowths in the quadrifid cells. Antibodies (JIM8, JIM13, JIM14, MAC207, and JIM4) that act against various groups of AGPs were used. AGP localization was determined using immunohistochemistry techniques and immunogold labeling. AGPs localized with the JIM13, JIM8, and JIM14 epitopes occurred in wall ingrowths of the pedestal cell, which may be related to the fact that AGPs regulate the formation of wall ingrowths but also, due to the patterning of the cell wall structure, affect symplastic transport. The presence of AGPs in the cell wall of terminal cells may be related to the presence of wall ingrowths, but processes also involve vesicle trafficking and membrane recycling, in which these proteins participate.
Assuntos
Parede Celular , Mucoproteínas , Proteínas de Plantas , Mucoproteínas/metabolismo , Proteínas de Plantas/metabolismo , Parede Celular/metabolismo , Tricomas/metabolismo , Folhas de Planta/metabolismo , Lamiales/metabolismoRESUMO
This study aimed to confirm macrophage-stimulatory component from Korean meadowsweet (Filipendula glaberrima; FG) and characterize its compositional and structural properties. FG-CWH, prepared via cool-water extraction and ethanol precipitation, induced the highest secretion of NO (6.0-8.0 µM), TNF-α (8.7-9.5 ng/mL), and IL-6 (1.0-5.7 ng/mL) compared to other samples at 0.4-10 µg/mL in RAW 264.7 cells. Analytical results revealed that FG-CWH is a high-molecular-weight component with an average molecular weight of 220 kDa, constituting a polysaccharide-protein mixture. Chemical and enzymatic treatment of FG-CWH indicated its primary composition as arabinogalactan protein (AGP)-rich glycoprotein, with activity likely associated with the chemical and structural characteristics of AGP. FG-CWH treatment resulted in significant and concentration-dependent increases in iNOS (20.0-29.6 folds), TNFα (10.6-18.6 folds) and IL6 (10.9-155.6 folds) gene expression, as well as the secretion of NO (5.3-6.3 µM), TNF-α (35.4-44.3 ng/mL), and IL-6 (4.1-8.4 ng/mL) secretion, even at a reduced concentration range of 125-500 ng/mL, compared to the negative control group. Immunoblotting analysis indicated FG-CWH-induced macrophage stimulation significantly associated with the activation of MAPK (ERK, JNK, and p38) and NF-κB (p65 and IκBα). These findings can serve as valuable groundwork for developing FG-derived AGP as novel functional ingredients to enhance human immunity.
Assuntos
Ativação de Macrófagos , Macrófagos , Mucoproteínas , Proteínas de Plantas , Camundongos , Animais , Células RAW 264.7 , Mucoproteínas/química , Mucoproteínas/metabolismo , Ativação de Macrófagos/efeitos dos fármacos , Proteínas de Plantas/química , Proteínas de Plantas/farmacologia , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Óxido Nítrico/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Interleucina-6/metabolismo , Peso Molecular , NF-kappa B/metabolismoRESUMO
A microRNA miR-200c-3p is a regulator of epithelial-mesenchymal transition to control adhesion and migration of epithelial and mesenchymal cells. However, little is known about whether miR-200c-3p affects lymphocyte adhesion and migration mediated by integrins. Using TK-1 (a T lymphoblast cell) as a model of T cell, here we show that repressed expression of miR-200c-3p upregulated α4 integrin-mediated adhesion to and migration across mucosal addressin cell adhesion molecule-1 (MAdCAM-1). Conversely, overexpression of miR-200c-3p downregulated α4 integrin-mediated adhesion and migration. Unlike in epithelial cells, miR-200c-3p did not target talin, a conformation activator of integrin, but, targeted E26-transformation-specific sequence 1 (ETS1), a transcriptional activator of α4 integrin, in T cells. Treatment of the miR-200c-3p-low-expressing TK-1 cells that possessed elevated α4 integrin with ETS1 small interfering RNA (siRNA) resulted in the reversion of the α4 integrin expression, supporting that ETS1 is a target of miR-200c-3p. A potential proinflammatory immune-modulator retinoic acid (RA) treatment of TK-1 cells elicited a significant reduction of miR-200c-3p and simultaneously a marked increase in ETS1 and α4 integrin expression. An anti-inflammatory cytokine TGF-ß1 treatment elevated miR-200c-3p, thereby downregulating ETS1 and α4 integrin expression. These results suggest that miR-200c-3p is an important regulator of α4 integrin expression and functions and may be controlled by RA and TGF-ß1 in an opposite way. Overexpression of miR-200c-3p could be a novel therapeutic option for treatment of gut inflammation through suppressing α4 integrin-mediated T cell migration.
Assuntos
Adesão Celular , Movimento Celular , Integrina alfa4 , MicroRNAs , Linfócitos T , MicroRNAs/genética , MicroRNAs/metabolismo , Humanos , Integrina alfa4/metabolismo , Integrina alfa4/genética , Movimento Celular/genética , Adesão Celular/genética , Linfócitos T/metabolismo , Proteína Proto-Oncogênica c-ets-1/metabolismo , Proteína Proto-Oncogênica c-ets-1/genética , Mucoproteínas/genética , Mucoproteínas/metabolismo , Fator de Crescimento Transformador beta1/metabolismo , Imunoglobulinas/genética , Imunoglobulinas/metabolismo , Moléculas de Adesão Celular/metabolismo , Moléculas de Adesão Celular/genética , Linhagem CelularRESUMO
BACKGROUND: Canine mammary tumors (CMTs) in intact female dogs provide a natural model for investigating metastatic human cancers. Our prior research identified elevated expression of Anterior Gradient 2 (AGR2), a protein disulfide isomerase (PDI) primarily found in the endoplasmic reticulum (ER), in CMT tissues, highly associated with CMT progression. We further demonstrated that increased AGR2 expression actively influences the extracellular microenvironment, promoting chemotaxis in CMT cells. Unraveling the underlying mechanisms is crucial for assessing the potential of therapeutically targeting AGR2 as a strategy to inhibit a pro-metastatic microenvironment and impede tumor metastasis. METHODS: To identify the AGR2-modulated secretome, we employed proteomics analysis of the conditioned media (CM) from two CMT cell lines ectopically expressing AGR2, compared with corresponding vector-expressing controls. AGR2-regulated release of 14-3-3ε (gene: YWHAE) and α-actinin 4 (gene: ACTN4) was validated through ectopic expression, knockdown, and knockout of the AGR2 gene in CMT cells. Extracellular vesicles derived from CMT cells were isolated using either differential ultracentrifugation or size exclusion chromatography. The roles of 14-3-3ε and α-actinin 4 in the chemotaxis driven by the AGR2-modulated CM were investigated through gene knockdown, antibody-mediated interference, and recombinant protein supplement. Furthermore, the clinical relevance of the release of 14-3-3ε and α-actinin 4 was assessed using CMT tissue-immersed saline and sera from CMT-afflicted dogs. RESULTS: Proteomics analysis of the AGR2-modulated secretome revealed increased abundance in 14-3-3ε and α-actinin 4. Ectopic expression of AGR2 significantly increased the release of 14-3-3ε and α-actinin 4 in the CM. Conversely, knockdown or knockout of AGR2 expression remarkably reduced their release. Silencing 14-3-3ε or α-actinin 4 expression diminished the chemotaxis driven by AGR2-modulated CM. Furthermore, AGR2 controls the release of 14-3-3ε and α-actinin 4 primarily via non-vesicular routes, responding to the endoplasmic reticulum (ER) stress and autophagy activation. Knockout of AGR2 resulted in increased α-actinin 4 accumulation and impaired 14-3-3ε translocation in autophagosomes. Depletion of extracellular 14-3-3ε or α-actinin 4 reduced the chemotaxis driven by AGR2-modulated CM, whereas supplement with recombinant 14-3-3ε in the CM enhanced the CM-driven chemotaxis. Notably, elevated levels of 14-3-3ε or α-actinin 4 were observed in CMT tissue-immersed saline compared with paired non-tumor samples and in the sera of CMT dogs compared with healthy dogs. CONCLUSION: This study elucidates AGR2's pivotal role in orchestrating unconventional secretion of 14-3-3ε and α-actinin 4 from CMT cells, thereby contributing to paracrine-mediated chemotaxis. The insight into the intricate interplay between AGR2-involved ER stress, autophagy, and unconventional secretion provides a foundation for refining strategies aimed at impeding metastasis in both canine mammary tumors and potentially human cancers.
Assuntos
Proteínas 14-3-3 , Actinina , Autofagia , Quimiotaxia , Estresse do Retículo Endoplasmático , Neoplasias Mamárias Animais , Mucoproteínas , Animais , Cães , Proteínas 14-3-3/metabolismo , Proteínas 14-3-3/genética , Feminino , Actinina/metabolismo , Actinina/genética , Neoplasias Mamárias Animais/metabolismo , Neoplasias Mamárias Animais/genética , Neoplasias Mamárias Animais/patologia , Linhagem Celular Tumoral , Quimiotaxia/genética , Autofagia/genética , Estresse do Retículo Endoplasmático/genética , Mucoproteínas/genética , Mucoproteínas/metabolismo , Proteínas Oncogênicas/metabolismo , Proteínas Oncogênicas/genéticaRESUMO
Integrin α4ß7+ T cells perpetuate tissue injury in chronic inflammatory diseases, yet their role in hepatic fibrosis progression remains poorly understood. Here, we report increased accumulation of α4ß7+ T cells in the liver of people with cirrhosis relative to disease controls. Similarly, hepatic fibrosis in the established mouse model of CCl4-induced liver fibrosis was associated with enrichment of intrahepatic α4ß7+ CD4 and CD8 T cells. Monoclonal antibody (mAb)-mediated blockade of α4ß7 or its ligand mucosal addressin cell adhesion molecule (MAdCAM)-1 attenuated hepatic inflammation and prevented fibrosis progression in CCl4-treated mice. Improvement in liver fibrosis was associated with a significant decrease in the infiltration of α4ß7+ CD4 and CD8 T cells, suggesting that α4ß7/MAdCAM-1 axis regulates both CD4 and CD8 T cell recruitment to the fibrotic liver, and α4ß7+ T cells promote hepatic fibrosis progression. Analysis of hepatic α4ß7+ and α4ß7- CD4 T cells revealed that α4ß7+ CD4 T cells were enriched for markers of activation and proliferation, demonstrating an effector phenotype. The findings suggest that α4ß7+ T cells play a critical role in promoting hepatic fibrosis progression, and mAb-mediated blockade of α4ß7 or MAdCAM-1 represents a promising therapeutic strategy for slowing hepatic fibrosis progression in chronic liver diseases.
Assuntos
Moléculas de Adesão Celular , Progressão da Doença , Integrinas , Cirrose Hepática , Fígado , Mucoproteínas , Animais , Feminino , Humanos , Masculino , Camundongos , Anticorpos Monoclonais/farmacologia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD8-Positivos/imunologia , Moléculas de Adesão Celular/metabolismo , Modelos Animais de Doenças , Imunoglobulinas/metabolismo , Inflamação/patologia , Integrinas/metabolismo , Fígado/patologia , Fígado/metabolismo , Cirrose Hepática/induzido quimicamente , Cirrose Hepática/imunologia , Cirrose Hepática/patologia , Camundongos Endogâmicos C57BL , Mucoproteínas/metabolismo , Linfócitos T/imunologia , Linfócitos T/metabolismo , Tetracloreto de Carbono/farmacologia , Tetracloreto de Carbono/toxicidadeRESUMO
Resident memory T cells (TRMs) help control local immune homeostasis and contribute to tissue-protective immune responses. The local cues that guide their differentiation and localization are poorly defined. We demonstrate that mucosal vascular addressin cell adhesion molecule 1, a ligand for the gut-homing receptor α4ß7 integrin, in the presence of retinoic acid and transforming growth factor-ß (TGF-ß) provides a co-stimulatory signal that induces blood cluster of differentiation (CD8+ T cells to adopt a TRM-like phenotype. These cells express CD103 (integrin αE) and CD69, the two major TRM cell-surface markers, along with CD101. They also express C-C motif chemokine receptors 5 (CCR5) , C-C motif chemokine receptors 9 (CCR9), and α4ß7, three receptors associated with gut homing. A subset also expresses E-cadherin, a ligand for αEß7. Fluorescent lifetime imaging indicated an αEß7 and E-cadherin cis interaction on the plasma membrane. This report advances our understanding of the signals that drive the differentiation of CD8+ T cells into resident memory T cells and provides a means to expand these cells in vitro, thereby affording an avenue to generate more effective tissue-specific immunotherapies.
Assuntos
Antígenos CD , Antígenos de Diferenciação de Linfócitos T , Linfócitos T CD8-Positivos , Cadeias alfa de Integrinas , Fator de Crescimento Transformador beta , Tretinoína , Tretinoína/farmacologia , Animais , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Camundongos , Cadeias alfa de Integrinas/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Antígenos CD/metabolismo , Antígenos de Diferenciação de Linfócitos T/metabolismo , Memória Imunológica , Moléculas de Adesão Celular/metabolismo , Caderinas/metabolismo , Lectinas Tipo C/metabolismo , Diferenciação Celular , Mucoproteínas/metabolismo , Receptores CCR/metabolismo , Células T de Memória/imunologia , Células T de Memória/metabolismo , Imunoglobulinas/metabolismo , Camundongos Endogâmicos C57BL , Mucosa Intestinal/imunologia , Mucosa Intestinal/metabolismo , Integrinas/metabolismo , FenótipoRESUMO
Carotenoids are important pigmented nutrients synthesized by tomato fruits during ripening. To reveal the molecular mechanism underlying carotenoid synthesis during tomato fruit ripening, we analyzed carotenoid metabolites and transcriptomes in six development stages of tomato fruits. A total of thirty different carotenoids were detected and quantified in tomato fruits from 10 to 60 DPA. Based on differential gene expression profiles and WGCNA, we explored several genes that were highly significant and negatively correlated with lycopene, all of which encode fasciclin-like arabinogalactan proteins (FLAs). The FLAs are involved in plant signal transduction, however the functional role of these proteins has not been studied in tomato. Genome-wide analysis revealed that cultivated and wild tomato species contained 18 to 22 FLA family members, clustered into four groups, and mainly evolved by means of segmental duplication. The functional characterization of FLAs showed that silencing of SlFLA1, 5, and 13 were found to contribute to the early coloration of tomato fruits, and the expression of carotenoid synthesis-related genes was up-regulated in fruits that changed phenotypically, especially in SlFLA13-silenced plants. Furthermore, the content of multiple carotenoids (including (E/Z)-phytoene, lycopene, γ-carotene, and α-carotene) was significantly increased in SlFLA13-silenced fruits, suggesting that SlFLA13 has a potential inhibitory function in regulating carotenoid synthesis in tomato fruits. The results of the present study broaden the idea of analyzing the biological functions of tomato FLAs and preliminary evidence for the inhibitory role of SlFLA13 in carotenoid synthesis in fruit, providing the theoretical basis and a candidate for improving tomato fruit quality.
Assuntos
Carotenoides , Frutas , Proteínas de Plantas , Solanum lycopersicum , Solanum lycopersicum/genética , Solanum lycopersicum/metabolismo , Solanum lycopersicum/crescimento & desenvolvimento , Carotenoides/metabolismo , Frutas/metabolismo , Frutas/genética , Frutas/crescimento & desenvolvimento , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Regulação da Expressão Gênica de Plantas , Galactanos/metabolismo , Galactanos/biossíntese , Mucoproteínas/metabolismo , Mucoproteínas/genéticaRESUMO
INTRODUCTION: Multiple sclerosis (MS) is an autoimmune disease of the central nervous system. Recent evidence suggests that lymphocyte trafficking in the intestines could play a key role in its etiology. Nevertheless, it is not clear how intestinal tissue is involved in the disease onset nor its evolution. In the present study, we aimed to evaluate intestinal inflammation dynamic throughout the disease course and its potential impact on disease progression. METHODS: We used tissue immunophenotyping (immunohistofluorescence and flow cytometry) and a recently described molecular magnetic resonance imaging (MRI) method targeting mucosal addressin cell adhesion molecule-1 (MAdCAM-1) to assess intestinal inflammation in vivo in two distinct animal models of MS (Experimental Autoimmune Encephalomyelitis - EAE) at several time points of disease progression. RESULTS: We report a positive correlation between disease severity and MAdCAM-1 MRI signal in two EAE models. Moreover, high MAdCAM-1 MRI signal during the asymptomatic phase is associated with a delayed disease onset in progressive EAE and to a lower risk of conversion to a secondary-progressive form in relapsing-remitting EAE. During disease evolution, in line with a bi-directional immune communication between the gut and the central nervous system, we observed a decrease in T-CD4+ and B lymphocytes in the ileum concomitantly with their increase in the spinal cord. CONCLUSION: Altogether, these data unveil a crosstalk between intestinal and central inflammation in EAE and support the use of molecular MRI of intestinal MAdCAM-1 as a new biomarker for prognostic in MS patients.
Assuntos
Biomarcadores , Modelos Animais de Doenças , Encefalomielite Autoimune Experimental , Imageamento por Ressonância Magnética , Camundongos Endogâmicos C57BL , Mucoproteínas , Esclerose Múltipla , Animais , Encefalomielite Autoimune Experimental/metabolismo , Encefalomielite Autoimune Experimental/diagnóstico por imagem , Esclerose Múltipla/diagnóstico por imagem , Esclerose Múltipla/metabolismo , Esclerose Múltipla/patologia , Imageamento por Ressonância Magnética/métodos , Camundongos , Biomarcadores/metabolismo , Mucoproteínas/metabolismo , Feminino , Prognóstico , Progressão da Doença , Moléculas de Adesão Celular/metabolismo , Intestinos/diagnóstico por imagem , Intestinos/patologia , Imunoglobulinas/metabolismo , Inflamação/metabolismo , Inflamação/diagnóstico por imagem , Mucosa Intestinal/metabolismo , Mucosa Intestinal/diagnóstico por imagemRESUMO
Graphene quantum dots (GQDs) have attracted significant attention in biomedicine, while extensive investigations have revealed a reverse regarding the potential biotoxicity of GQDs. In order to supplementing the understanding of the toxicity profile of GQDs, this study employs a molecular dynamics (MD) simulation approach to systematically investigate the potential toxicity of both GQDs and Graphene Oxide Quantum Dots (GOQDs) on the Anterior Gradient Homolog 2 (AGR2) protein, a key protein capable of protecting the intestine. We construct two typical simulation systems, in which an AGR2 protein is encircled by either GQDs or GOQDs. The MD results demonstrate that both GQDs and GOQDs can directly make contact with and even cover the active site (specifically, the Cys81 amino acid) of the AGR2 protein. This suggests that GQDs and GOQDs have the capability to inhibit or interfere with the normal biological interaction of the AGR2 active site with its target protein. Thus, GQDs and GOQDs exhibit potential detrimental effects on the AGR2 protein. Detailed analyses reveal that GQDs adhere to the Cys81 residue due to van der Waals (vdW) interaction forces, whereas GOQDs attach to the Cys81 residue through a combination of vdW (primary) and Coulomb (secondary) interactions. Furthermore, GQDs aggregation typically adsorb onto the AGR2 active site, while GOQDs adsorb to the active site of AGR2 one by one. Consequently, these findings shed new light on the potential adverse impact of GQDs and GOQDs on the AGR2 protein via directly covering the active site of AGR2, providing valuable molecular insights for the toxicity profile of GQD nanomaterials.
Assuntos
Grafite , Mucoproteínas , Pontos Quânticos , Domínio Catalítico , Grafite/toxicidade , Grafite/química , Simulação de Dinâmica Molecular , Óxidos , Pontos Quânticos/toxicidade , Pontos Quânticos/química , Mucoproteínas/metabolismo , Proteínas Oncogênicas/metabolismoRESUMO
BACKGROUND: Pancreatic neuroendocrine tumors (PNETs) with low microvessel density and fibrosis often exhibit clinical aggressiveness. Given the contribution of cancer-associated fibroblasts (CAFs) to the hypovascular fibrotic stroma in pancreatic ductal adenocarcinoma, investigating whether CAFs play a similar role in PNETs becomes imperative. In this study, we investigated the involvement of CAFs in PNETs and their effects on clinical outcomes. METHODS: We examined 79 clinical PNET specimens to evaluate the number and spatial distribution of α-smooth muscle actin (SMA)-positive cells, which are indicative of CAFs. Then, the findings were correlated with clinical outcomes. In vitro and in vivo experiments were conducted to assess the effects of CAFs (isolated from clinical specimens) on PNET metastasis and growth. Additionally, the role of the stromal-cell-derived factor 1 (SDF1)-AGR2 axis in mediating communication between CAFs and PNET cells was investigated. RESULTS: αSMA-positive and platelet-derived growth factor-α-positive CAFs were detected in the hypovascular stroma of PNET specimens. A higher abundance of α-SMA-positive CAFs within the PNET stroma was significantly associated with a higher level of clinical aggressiveness. Notably, conditioned medium from PNET cells induced an inflammatory phenotype in isolated CAFs. These CAFs promoted PNET growth and metastasis. Mechanistically, PNET cells secreted interleukin-1, which induced the secretion of SDF1 from CAFs. This cascade subsequently elevated AGR2 expression in PNETs, thereby promoting tumor growth and metastasis. The downregulation of AGR2 in PNET cells effectively suppressed the CAF-mediated promotion of PNET growth and metastasis. CONCLUSION: CAFs drive the growth and metastasis of aggressive PNETs. The CXCR4-SDF1 axis may be a target for antistromal therapy in the treatment of PNET. This study clarifies mechanisms underlying PNET aggressiveness and may guide future therapeutic interventions targeting the tumor microenvironment.
Assuntos
Fibroblastos Associados a Câncer , Tumores Neuroectodérmicos Primitivos , Tumores Neuroendócrinos , Neoplasias Pancreáticas , Humanos , Fibroblastos Associados a Câncer/metabolismo , Tumores Neuroendócrinos/patologia , Linhagem Celular Tumoral , Neoplasias Pancreáticas/patologia , Tumores Neuroectodérmicos Primitivos/metabolismo , Tumores Neuroectodérmicos Primitivos/patologia , Microambiente Tumoral , Fibroblastos/metabolismo , Mucoproteínas/metabolismo , Mucoproteínas/uso terapêutico , Proteínas Oncogênicas/metabolismoRESUMO
As a key component in cell walls of numerous organisms ranging from green algae to higher plants, AGPs play principal roles in many biological processes such as cell-cell adhesion and regulating Ca2+ signaling pathway as a Ca2+-capacitor. Consistently, AGP structures vary from species to species and from tissue to tissue. To understand the functions of AGPs, it is vital to know their structural differences relative to their location in the plant. Thus, AGPs were purified from different Arabidopsis tissues. Analyses of these AGPs demonstrated that the AGPs comprised covalently linked pectin and AGP, referred to as pectic-AGPs. Importantly, these pectic-AGPs were glycosylated with a remarkable variety of polysaccharides including homogalacturonan, rhamnogalacturonan-I, and type II arabinogalactan at different ratios and lengths. This result not only suggests that pectic-AGP is a major form of Arabidopsis AGPs, but also supports AGPs serve as crosslinkers covalently connecting pectins with structures tailored for tissue-specific functions.
Assuntos
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/metabolismo , Proteínas de Plantas/metabolismo , Mucoproteínas/metabolismo , Pectinas/metabolismo , Proteínas de Arabidopsis/metabolismo , Parede Celular/químicaRESUMO
One of the main obstacles to therapeutic success in colorectal cancer (CRC) is the development of acquired resistance to treatment with drugs such as 5-fluorouracil (5-FU). Whilst some resistance mechanisms are well known, it is clear from the stasis in therapy success rate that much is still unknown. Here, a proteomics approach is taken towards identification of candidate proteins using 5-FU-resistant sublines of human CRC cell lines generated in house. Using a multiplexed stable isotope labelling with amino acids in cell culture (SILAC) strategy, 5-FU-resistant and equivalently passaged sensitive cell lines were compared to parent cell lines by growing in Heavy medium with 2D liquid chromatography and Orbitrap Fusion™ Tribrid™ Mass Spectrometry analysis. Among 3003 commonly quantified proteins, six (CD44, APP, NAGLU, CORO7, AGR2, PLSCR1) were found up-regulated, and six (VPS45, RBMS2, RIOK1, RAP1GDS1, POLR3D, CD55) down-regulated. A total of 11 of the 12 proteins have a known association with drug resistance mechanisms or role in CRC oncogenesis. Validation through immunodetection techniques confirmed high expression of CD44 and CD63, two known drug resistance mediators with elevated proteomics expression results. The information revealed by the sensitivity of this method warrants it as an important tool for elaborating the complexity of acquired drug resistance in CRC.
Assuntos
Neoplasias Colorretais , Fluoruracila , Humanos , Fluoruracila/farmacologia , Fluoruracila/uso terapêutico , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/metabolismo , Proteômica , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos , Mucoproteínas , Proteínas OncogênicasRESUMO
Using 7 % KOH, the polysaccharide PAK has been isolated from the coniferous greens of Norway spruce. PAK was found to contain predominantly arabinoglucuronoxylan, xyloglucan and arabinan, but also pectic polysaccharides, glucomannan and arabinogalactan proteins (AGPs), as determined by 1D/2D NMR analysis. It was found that fractionation of PAK on DEAE-cellulose resulted in simultaneous elution of pectins, arabinoglucuronoxylans and AGPs. It was evident that the content of 4-OMe-α-D-GlcpA and xylose, 1,4-ß-D-GlcpA, and T-ß-D-GlcpA increased with an increase in NaCl concentration. However, 1,4-α-D-GalpA content was almost independent of NaCl concentration, indicating unchanged pectic polysaccharide concentration. Interestingly, pectins extracted with 0.1-0.3 M NaCl solutions were richer in rhamnogalacturonan-I (RG-I) than those extracted with water and 0.01 M NaCl. Conclusion: The content of RG-I, AGPs and arabinoglucuronoxylan rises with rising NaCl concentration. An intense signal indicating an intermolecular linkage between the xylan and RG-I domains, i.e. that part of the arabinoglucuronoxylan is covalently bound to RG-I, is observed in the HMBC spectra of the polysaccharides obtained. The discovery here of a new relationship between rhamnogalacturonan I and xylan contradicts the prevailing cell wall model.
Assuntos
Abies , Mucoproteínas , Picea , Xilanos , Abies/metabolismo , Cloreto de Sódio , Polissacarídeos/química , Pectinas/química , Proteínas de PlantasRESUMO
AIMS: The histological subtype of intrahepatic cholangiocarcinoma (iCCA) is associated with different mutational characteristics that impact clinical management. So far, data are lacking on the presence of small duct iCCA (SD-iCCA) and large duct iCCA (LD-iCCA) in a single patient. The aim of the current study was to determine the presence and degree of intratumoural heterogeneity of SD- and LD-iCCA features in different tumour regions. METHODS AND RESULTS: All patients treated with surgically resected iCCA at Frankfurt University Hospital between December 2005 and March 2023 were retrospectively analysed. Histomorphological features of SD- and LD-iCCA were evaluated by an expert hepatobiliary pathologist. Tissue samples suspicious for subtype heterogeneity were further investigated. Immunohistochemistry for N-cadherin, S100P, MUC5AC, MUC6, TFF1 and AGR2 and mutational profiling with the Illumina TruSight Oncology 500 (TSO500) assay were performed separately for the SD- and LD-iCCA regions. Of 129 patients with surgically resected iCCA, features of either SD- or LD-iCCA were present in 67.4% (n = 87) and 24.8% of the patients (n = 32), respectively; 7.8% (n = 10) had histomorphological features of both SD- and LD-iCCA, seven patients (5.4%) of which had sufficient formalin-fixed, paraffin-embedded tissue for further analysis. Heterogeneity of both subtypes could be confirmed with immunohistochemistry. In five of seven (71.4%) patients, molecular profiling revealed intratumoural differences in genetic alterations between the SD- and LD-iCCA region. In one patient, a BRAF mutation (p.V600E) was found in the SD-iCCA but not in the LD-iCCA region of the tumour. CONCLUSIONS: A marked portion of patients with iCCA exhibits both SD- and LD-iCCA in different tumour regions. In case of the presence of histopathological heterogeneity, mutational profiling should be considered to avoid missing therapeutically relevant genetic alterations.
Assuntos
Neoplasias dos Ductos Biliares , Colangiocarcinoma , Humanos , Estudos Retrospectivos , Colangiocarcinoma/genética , Colangiocarcinoma/patologia , Mutação , Ductos Biliares Intra-Hepáticos/patologia , Neoplasias dos Ductos Biliares/genética , Neoplasias dos Ductos Biliares/patologia , Mucoproteínas/genética , Proteínas Oncogênicas/genéticaRESUMO
Effector mechanisms of the unfolded protein response (UPR) in the endoplasmic reticulum (ER) are well-characterised, but how ER proteostasis is sensed is less well understood. Here, we exploited the beta isoform of the UPR transducer IRE1, that is specific to mucin-producing cells in order to gauge the relative regulatory roles of activating ligands and repressing chaperones of the specialised ER of goblet cells. Replacement of the stress-sensing luminal domain of endogenous IRE1α in CHO cells (normally expressing neither mucin nor IRE1ß) with the luminal domain of IRE1ß deregulated basal IRE1 activity. The mucin-specific chaperone AGR2 repressed IRE1 activity in cells expressing the domain-swapped IRE1ß/α chimera, but had no effect on IRE1α. Introduction of the goblet cell-specific client MUC2 reversed AGR2-mediated repression of the IRE1ß/α chimera. In vitro, AGR2 actively de-stabilised the IRE1ß luminal domain dimer and formed a reversible complex with the inactive monomer. These features of the IRE1ß-AGR2 couple suggest that active repression of IRE1ß by a specialised mucin chaperone subordinates IRE1 activity to a proteostatic challenge unique to goblet cells, a challenge that is otherwise poorly recognised by the pervasive UPR transducers.