RESUMO
This study focuses on the synthesis and structural characterization of new compounds that integrate thiazolidine-2,4-dione, acridine moiety, and an acetamide linker, aiming to leverage the synergistic effects of these pharmacophores for enhanced therapeutic potential. The newly designed molecules were efficiently synthesized through a multi-step process and subsequently transformed into their hydrochloride salts. Comprehensive spectroscopic techniques, including nuclear magnetic resonance (NMR), high-resolution mass spectrometry (HRMS), infrared (IR) spectroscopy, and elemental analysis, were employed to determine the molecular structures of the synthesized compounds. Biological evaluations were conducted to assess the therapeutic potential of the new compounds. The influence of these derivatives on the metabolic activity of various cancer cell lines was assessed, with IC50 values determined via MTT assays. An in-depth analysis of the structure-activity relationship (SAR) revealed intriguing insights into their cytotoxic profiles. Compounds with electron-withdrawing groups generally exhibited lower IC50 values, indicating higher potency. The presence of the methoxy group at the linking phenyl ring modulated both the potency and selectivity of the compounds. The variation in the acridine core at the nitrogen atom of the thiazolidine-2,4-dione core significantly affects the activity against cancer cell lines, with the acridin-9-yl substituent enhancing the compounds' antiproliferative activity. Furthermore, compounds in their hydrochloride salt forms demonstrated better activity against cancer cell lines compared to their free base forms. Compounds 12c·2HCl (IC50 = 5.4 ± 2.4 µM), 13d (IC50 = 4.9 ± 2.9 µM), and 12f·2HCl (IC50 = 4.98 ± 2.9 µM) demonstrated excellent activity against the HCT116 cancer cell line, and compound 7d·2HCl (IC50 = 4.55 ± 0.35 µM) demonstrated excellent activity against the HeLa cancer cell line. Notably, only a few tested compounds, including 7e·2HCl (IC50 = 11.00 ± 2.2 µM), 7f (IC50 = 11.54 ± 2.06 µM), and 7f·2HCl (IC50 = 9.82 ± 1.92 µM), showed activity against pancreatic PATU cells. This type of cancer has a very high mortality due to asymptomatic early stages, the occurrence of metastases, and frequent resistance to chemotherapy. Four derivatives, namely, 7e·2HCl, 12d·2HCl, 13c·HCl, and 13d, were tested for their interaction properties with BSA using fluorescence spectroscopic studies. The values for the quenching constant (Ksv) ranged from 9.59 × 104 to 10.74 × 104 M-1, indicating a good affinity to the BSA protein.
Assuntos
Acridinas , Antineoplásicos , Desenho de Fármacos , Tiazolidinedionas , Humanos , Antineoplásicos/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Tiazolidinedionas/química , Tiazolidinedionas/farmacologia , Tiazolidinedionas/síntese química , Acridinas/química , Acridinas/farmacologia , Acridinas/síntese química , Linhagem Celular Tumoral , Relação Estrutura-Atividade , Proliferação de Células/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Estrutura MolecularRESUMO
The synthesis, anticancer, and antioxidant activities of a series of indole-derived hybrid chalcones are reported here. First, using the well-known Claisen-Schmidt condensation method, a set of 29 chalcones has been designed, synthesized, and consequently characterized. Subsequently, screening for the antiproliferative activity of the synthesized hybrid chalcones was performed on five cancer cell lines (HCT116, HeLa, Jurkat, MDA-MB-231, and MCF7) and two non-cancer cell lines (MCF-10A and Bj-5ta). Chalcone 18c, bearing 1-methoxyindole and catechol structural features, exhibited selective activity against cancer cell lines with IC50 values of 8.0 ± 1.4 µM (Jurkat) and 18.2 ± 2.9 µM (HCT116) and showed no toxicity to non-cancer cells. Furthermore, antioxidant activity was evaluated using three different methods. The in vitro studies of radical scavenging activity utilizing DPPH radicals as well as the FRAP method demonstrated the strong activity of catechol derivatives 18a-c. According to the ABTS radical scavenging assay, the 3-methoxy-4-hydroxy-substituted chalcones 19a-c were slightly more favorable. In general, a series of 3,4-dihydroxychalcone derivatives showed properties as a lead compound for both antioxidant and antiproliferative activity.
RESUMO
Derivatives combining acridine, pyrrole, and thiazolidine rings have emerged as promising candidates in the field of antitumor drug discovery. This paper aims to highlight the importance of these three structural motifs in developing potent and selective anticancer agents. The integration of these rings within a single molecule offers the potential for synergistic effects, targeting multiple pathways involved in tumor growth and progression. Spiro derivatives were efficiently synthesized in a two-step process starting from isothiocyanates and 2-cyanoacetohydrazide. The thiourea side chain in spiro derivatives was utilized as a key component for the construction of the thiazolidine-4-one ring through regioselective reactions with bifunctional reagents, namely methyl-bromoacetate, dietyl-acetylenedicarboxylate, ethyl-2-bromopropionate, and ethyl-2-bromovalerate. These reactions resulted in the formation of a single regioisomeric product for each derivative. Advanced spectroscopic techniques, including 1D and 2D NMR, FT-IR, HRMS, and single-crystal analysis, were employed to meticulously characterize the chemical structures of the synthesized derivatives. Furthermore, the influence of these derivatives on the metabolic activity of various cancer cell lines was assessed, with IC50 values determined via MTT assays. Notably, derivatives containing ester functional groups exhibited exceptional activity against all tested cancer cell lines, boasting IC50 values below 10 µM. Particularly striking were the spiro derivatives with methoxy groups at position 3 and nitro groups at position 4 of the phenyl ring. These compounds displayed remarkable selectivity and exhibited heightened activity against HCT-116 and Jurkat cell lines. Additionally, 4-oxo-1,3-thiazolidin-2-ylidene derivatives demonstrated a significant activity against MCF-7 and HCT-116 cancer cell lines.
Assuntos
Acridinas , Antineoplásicos , Humanos , Pirróis/farmacologia , Tiazolidinas/farmacologia , Espectroscopia de Infravermelho com Transformada de Fourier , Antineoplásicos/farmacologia , Células HCT116RESUMO
Dual-specificity mitogen-activated protein kinases kinases (MAPKKs) are the immediate upstream activators of MAPKs. They simultaneously phosphorylate the TXY motif within the activation loop of MAPKs, allowing them to interact with and regulate multiple substrates. Often, the activation of MAPKs triggers their nuclear translocation. However, the spatiotemporal dynamics and the physiological consequences of the activation of MAPKs, particularly in plants, are still poorly understood. Here, we studied the activation and localization of the Medicago sativa stress-induced MAPKK (SIMKK)-SIMK module after salt stress. In the inactive state, SIMKK and SIMK co-localized in the cytoplasm and in the nucleus. Upon salt stress, however, a substantial part of the nuclear pool of both SIMKK and SIMK relocated to cytoplasmic compartments. The course of nucleocytoplasmic shuttling of SIMK correlated temporally with the dual phosphorylation of the pTEpY motif. SIMKK function was further studied in Arabidopsis plants overexpressing SIMKK-yellow fluorescent protein (YFP) fusions. SIMKK-YFP plants showed enhanced activation of Arabidopsis MPK3 and MPK6 kinases upon salt treatment and exhibited high sensitivity against salt stress at the seedling stage, although they were salt insensitive during seed germination. Proteomic analysis of SIMKK-YFP overexpressors indicated the differential regulation of proteins directly or indirectly involved in salt stress responses. These proteins included catalase, peroxiredoxin, glutathione S-transferase, nucleoside diphosphate kinase 1, endoplasmic reticulum luminal-binding protein 2, and finally plasma membrane aquaporins. In conclusion, Arabidopsis seedlings overexpressing SIMKK-YFP exhibited higher salt sensitivity consistent with their proteome composition and with the presumptive MPK3/MPK6 hijacking of the salt response pathway.
Assuntos
Arabidopsis/metabolismo , Medicago sativa/enzimologia , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/metabolismo , Arabidopsis/genética , Arabidopsis/crescimento & desenvolvimento , Ativação Enzimática , Expressão Gênica , Medicago sativa/genética , Quinases de Proteína Quinase Ativadas por Mitógeno/genética , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/crescimento & desenvolvimento , Transporte Proteico , Sais/metabolismo , Plântula/genética , Plântula/crescimento & desenvolvimento , Plântula/metabolismoRESUMO
The amount of clinically relevant, allergy-related proteins in wheat grain is still largely unknown. The application of proteomics may create a platform not only for identification and characterization, but also for quantitation of these proteins. The aim of this study was to evaluate the data-independent quantitative mass spectrometry (MS(E)) approach in combination with 76 wheat allergenic sequences downloaded from the AllergenOnline database ( www.allergenonline.org ) as a starting point. Alcohol soluble extracts of gliadin and glutenin proteins were analyzed. This approach has resulted in identification and quantification of 15 allergenic protein isoforms that belong to amylase/trypsin inhibitors, γ-gliadins, and high or low molecular weight glutenins. Additionally, several peptides carrying four previously discovered epitopes of γ-gliadin B precursor have been detected. These data were validated against the UniProt database, which contained 11764 Triticeae protein sequences. The identified allergens are discussed in relation to Baker's asthma, food allergy, wheat dependent exercise induced anaphylaxis, atopic dermatitis, and celiac disease (i.e., gluten-sensitive enteropathy). In summary, the results showed that the MS(E) approach is suitable for quantitative analysis and allergens profiling in wheat varieties and/or other food matrices.
Assuntos
Epitopos/genética , Extratos Vegetais/genética , Proteínas de Plantas/metabolismo , Triticum/química , Antígenos de Plantas/genética , Antígenos de Plantas/metabolismo , Bases de Dados Genéticas , Espectrometria de Massas/métodos , Proteínas de Plantas/genética , ProteômicaRESUMO
Glycocylation represents the most complex and widespread post-translational modifications in human proteins. The variation of glycosylation is closely related to oncogenic transformation. Therefore, profiling of glycans detached from proteins is a promising strategy to identify biomarkers for cancer detection. This study identified candidate glycan biomarkers associated with hepatocellular carcinoma by mass spectrometry. Specifically, mass spectrometry data were analyzed with a peak selection procedure which incorporates multiple random sampling strategies with recursive feature selection based on support vector machines. Ten peak sets were obtained from different combinations of samples. Seven peaks were shared by each of the 10 peaksets, in which 7-12 peaks were selected, indicating 58-100% of peaks were shared by the 10 peaksets. Support vector machines and hierarchical clustering method were used to evaluate the performance of the peaksets. The predictive performance of the seven peaks was further evaluated by using 19 newly generated MALDI-TOF spectra. Glycan structures for four glycans of the seven peaks were determined. Literature search indicated that the structures of the four glycans could be found in some cancer-related glycoproteins. The method of this study is significant in deriving consistent, accurate, and biological significant glycan marker candidates for hepatocellular carcinoma diagnosis.
Assuntos
Biomarcadores Tumorais/sangue , Carcinoma Hepatocelular/sangue , Polissacarídeos/sangue , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Algoritmos , Análise por Conglomerados , Glicosilação , Humanos , Polissacarídeos/químicaRESUMO
Partially O-acetylated xylo-oligosaccharides (DXO) isolated from almond shells by autohydrolysis as well as their de-acetylated form (DeXO) were subjected to chemical, molecular, and structural analyses. They represent a mixture of neutral and acidic oligomers and low-molecular weight polymers related to (4-O-methyl-D-glucurono)-D-xylan. DXO and DeXO showed direct mitogenic activity and enhancement of the T-mitogen-induced proliferation of rat thymocytes, indicating the immunostimulatory potential of the almond shell xylo-oligosaccharides.
Assuntos
Adjuvantes Imunológicos/química , Adjuvantes Imunológicos/farmacologia , Oligossacarídeos/química , Oligossacarídeos/farmacologia , Prunus/química , Xilose , Espectroscopia de Ressonância Magnética , Prunus/imunologia , Espectroscopia de Infravermelho com Transformada de Fourier , Xilanos/análiseRESUMO
A series of 2-glycosyl-benzimidazoles with alpha-d-arabinopyranosyl, beta-d-galactopyranosyl, beta-d-glucopyranosyl, beta-d-mannopyranosyl, and beta-l-rhamnopyranosyl configurations were obtained in 52-73% yields from the corresponding C-glycosylmethanal dimethyl acetals and o-phenylenediamine under catalysis with hydrogen chloride or a strongly acidic cation-exchange resin. Intermediate benzimidazolines were spontaneously oxidized by air to produce the final products in the one-pot procedure. The prepared compounds did not show any inhibitory effect on the growth of 12 strains of five different species of pathogenic yeasts.
Assuntos
Acetais/química , Benzimidazóis/síntese química , Benzimidazóis/química , Glicosilação , Estrutura MolecularRESUMO
Fragmentation mechanisms of phytoalexin analogs, including brassitin and brassinin and their glucosylated analogs, have been studied by electrospray (ESI) ion trap (IT) multistage (MS(n), n = 1-4) mass spectrometry, matrix-assisted laser desorption/ionization time-of-flight (MALDI ToF/ToF) and ESI-Q/ToF tandem mass spectrometry techniques. At the fragmentation of sodium adducts a hitherto not described process has been elucidated The proposed mechanism of this process includes cyclization of the brassitin and brassinin cationized adducts through a six-membered cycle of the molecules and the elimination of isocyanate or isothiocyanate from the thio- or dithiocarbamate moiety, giving rise to [M + Na - 43](+) or [M + Na - 59](+) adducts. The elimination of NH=C=O or NH=C=S molecules has been confirmed by the high resolution measurement of the elemental composition of the ions produced and quantum-chemical calculations of the six-membered transition state. Other fragmentation routes include cleavage of an alkane linker, while numerous characteristic hexopyranose pathways are taking place in the glucosylated compounds. The presented theoretical data on the ESI and MALDI behavior of the saccharidic, as well as of the indole aglycon parts, can facilitate structural elucidation of the analogous compounds.
Assuntos
Anti-Infecciosos/química , Anticarcinógenos/química , Indóis/química , Espectrometria de Massas por Ionização por Electrospray/métodos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Espectrometria de Massas em Tandem/métodos , Tiocarbamatos/química , Cátions/química , Medicamentos de Ervas Chinesas/química , Glicosídeos/química , Estrutura Molecular , Extratos Vegetais/químicaRESUMO
Actin cytoskeleton is a vital cellular structure primarily known for controlling cell integrity, division and expansion. Here we present a proteomic dissection of Arabidopsis roots treated by actin depolymerizing agent latrunculin B. Pharmacological disintegration of the actin cytoskeleton by latrunculin B caused downregulation of several proteins involved in the actin organization and dynamics. Moreover, this approach helped to identify new protein candidates involved in gene transcription, due to the altered abundance of proteins involved in mRNA nuclear export. Finally, latrunculin B negatively affected the abundance of abscisic acid (ABA) responsive proteins. SIGNIFICANCE: This article substantially contributes to the current knowledge about the importance of actin organization and dynamics in proteome remodelling. We employed gel based and gel free proteomic analyses and identified several new protein candidates and protein networks linking actin dynamics to the gene transcription and to the ABA response in Arabidopsis.
Assuntos
Actinas/química , Arabidopsis/química , Raízes de Plantas/química , Proteoma/efeitos dos fármacos , Ácido Abscísico/fisiologia , Citoesqueleto de Actina/efeitos dos fármacos , Actinas/metabolismo , Proteínas de Arabidopsis/análise , Proteínas de Arabidopsis/química , Proteínas de Arabidopsis/metabolismo , Compostos Bicíclicos Heterocíclicos com Pontes/farmacologia , Polimerização/efeitos dos fármacos , Proteoma/análise , Proteômica/métodos , Tiazolidinas/farmacologiaRESUMO
Oligosaccharides (mono- to hexamers) that mimic the terminal epitopes of O-antigens of Vibrio cholerae O:1, serotypes Ogawa and Inaba, have been studied by electrospray ion trap (ESI IT) mass spectrometry. Sodium or potassium-cationized adducts are characteristic ions under the conditions of ESI-MS analysis. The tentative pathways of fragmentation have been proven by multistage ion trap MS (MS(n), n = 1-3). The predominant pathway of fragmentation of the oligomers is the neutral loss of monosaccharide residue shortening the length of the oligosaccharide. In this way, conversion of the Ogawa to Inaba fragments takes place under the conditions of measurement. ESI MS/MS provided sufficient information about molecular mass, the number of saccharide residues, and the structure of saccharides, about the C (4)-amide of 3-deoxy-L-glycero-tetronic acid (DGT) of the compounds investigated, and allows to distinguish between Ogawa and Inaba serotypes.
Assuntos
Antígenos de Bactérias/química , Lipopolissacarídeos/química , Espectrometria de Massas por Ionização por Electrospray/métodos , Vibrio cholerae/química , Configuração de Carboidratos , Lipopolissacarídeos/metabolismo , Estrutura Molecular , Espectrometria de Massas em Tandem/métodos , Vibrio cholerae/metabolismoRESUMO
Saccharides (mono through hexasaccharides) that mimic the terminal epitopes of O-antigens of Vibrio cholerae O:1, serotypes Ogawa and Inaba, were studied by electrospray ion trap (ESI IT) mass spectrometry (MS) in the negative mode. Anionized adducts are the characteristic ions formed by the capture of H(3)O(2)(-) under the condition of ESI MS analysis. The reactive species are produced by reaction of hydroxyl anions with the molecule of water. Thus the [M + H(3)O(2)](-) have the highest m/z value in the ESI IT negative mass spectra. After dissociation of adducts by loss of 2H(2)O the [M-H](-) ions are produced. The fragmentation pathways were confirmed by multistage measurements (MS(n)). The predominant pathway of fragmentation of the mono- and oligomers is the elimination of a molecule of alpha- hydroxy--gammabutyrolactone from the 4-(3-deoxy-L-glycero-tetronamido) group. The other characteristic pathway occurs by shortening the length of oligosaccharides. In this way, conversion of the Ogawa to Inaba fragments takes place under the conditions of measurement. Negative ESI MS/MS provided sufficient information about molecular mass, the number of saccharide residues, basic structure of saccharides, about the tetronamide part of the compounds investigated and allowed Ogawa and Inaba serotypes to be distinguished.
Assuntos
Antígenos de Bactérias/química , Polissacarídeos/química , Vibrio cholerae/química , Sequência de Carboidratos , Cromatografia Gasosa-Espectrometria de Massas , Dados de Sequência Molecular , Espectrometria de Massas por Ionização por ElectrosprayRESUMO
Saccharides (mono- to hexamers) that mimic the terminal epitopes of O-antigens of Vibrio cholerae O:1, serotypes Ogawa and Inaba have been studied by matrix-assisted laser desorption/ionization tandem time-of-flight (MALDI ToF/ToF) mass spectrometry (MS). Cationized adducts are the characteristic ions formed through the capture of sodium or potassium cations under MALDI MS conditions. Three characteristic pathways dominate in the fragmentation of model substances under MALDI ToF/ToF collision-induced dissociation MS/MS conditions of measurement. The first is the elimination which shortens the length of the oligosaccharide. In this way, conversion of the Ogawa to Inaba fragments takes place under the conditions of measurement. In the second, the conjugated transfer of electrons in the upstream unit of oligosaccharides takes place. The third route brings about the elimination of one alpha-hydroxy-gamma-butyrolactone molecule from the 4-(3-deoxy-L-glycero-tetronamido) group. The MALDI ToF/ToF MS/MS provided sufficient information about molecular mass, the number of saccharide residues, the structure of saccharides, the C(4)- amide of 3-deoxy-L-glycero-tetronic acid (DGT) of the compounds investigated, and allows to distinguish between Ogawa and Inaba serotypes.
Assuntos
Polissacarídeos/química , Vibrio cholerae O1/química , Aminoácidos/química , Sequência de Carboidratos , Indicadores e Reagentes , Dados de Sequência Molecular , Espectrometria de Massas por Ionização por Electrospray , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Espectrometria de Massas em TandemRESUMO
The aim of the present study is to rationalize acrylamide pendant Phos-Tag™ in-gel discrimination of phosphorylated and non-phosphorylated plant protein species with standard immunoblot analysis, and optimize sample preparation, efficient electrophoretic separation and transfer. We tested variants of the method including extraction buffers suitable for preservation of phosphorylated protein species in crude extracts from plants and we addressed the importance of the cation (Mn(2+) or Zn(2+)) used in the gel recipe for efficient transfer to PVDF membranes for further immunoblot analysis. We demonstrate the monitoring of Medicago sativa stress-induced mitogen activated protein kinase (SIMK) in stress-treated wild type plants and transgenic SIMKK RNAi line. We further show the hyperosmotically-induced phosphorylation of the previously uncharacterized HvMPK4 of barley. The method is validated using inducible phosphorylation of barley and wheat α-tubulin and of Arabidopsis MPK6. Acrylamide pendant Phos-Tag™offers a flexible tool for studying protein phosphorylation in crops and Arabidopsis circumventing radioactive labeling and the use of phosphorylation specific antibodies.
RESUMO
Fragmentation mechanisms of electrospray ionization (ESI) mass spectrometry of aldobiuronic and pseudoaldobiuronic acid derivatives were elucidated by multistage mass spectrometric (MS(n), n = 2-5) measurements of selected ions. Characteristic under the conditions of ESI-MS analysis is the production of alkali metal (Na and K) cationized adducts. The probability the of locations of Na cations in per-O-methylated compounds was proved by quantum chemical calculations, using the Jaguar program. The most probably position of alkali metal attachment is the carboxy group of the methoxycarbonyl C-5 group of the uronic acid unit. Characteristic cleavages vary according the kind of O-derivatization. In most cases they take place on the acidic part of the dimer and at the interglycosidic oxygen atom. As a result, the criteria for the differentiation of aldobiouronic and pseudoaldobiouronic acids derivatives were elucidated.
Assuntos
Dissacarídeos/química , Polissacarídeos/química , Ácidos Urônicos/química , Configuração de Carboidratos , Indicadores e Reagentes , Espectrometria de Massas por Ionização por Electrospray/métodosRESUMO
Protein phosphorylation is the most abundant and best studied protein posttranslational modification, dedicated to the regulation of protein function and subcellular localization as well as to protein-protein interactions. Identification and quantitation of the dynamic, conditional protein phosphorylation can be achieved by either metabolic labeling of the protein of interest with (32)P-labeled ATP followed by autoradiographic analysis, the use of specific monoclonal or polyclonal antibodies against the phosphorylated protein species and finally by phosphoproteome delineation using mass spectrometry.Hereby we present a fourth alternative which relies on the enforced-affinity-based-electrophoretic separation of phosphorylated from non-phosphorylated protein species by standard SDS-PAGE systems co-polymerized with Phos-Tag™ and Mn(2+) or Zn(2+) cations. Phosphate groups of phosphorylated Ser, Thr, and Tyr residues form complexes with Mn(2+) and Zn(2+) cations with polyacrylamide immobilized Phos-Tag™. Following appropriate treatment of the gels, separated proteins can be quantitatively transferred to PVDF or nitrocellulose membranes and probed with common-not phosphorylation state specific-antibodies and delineate the occurrence of a certain phosphoprotein species against its non-phosphorylated counterpart.
Assuntos
Acrilamida/química , Arabidopsis/enzimologia , Eletroforese em Gel de Poliacrilamida/métodos , Proteínas Quinases Ativadas por Mitógeno/isolamento & purificação , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Fosfoproteínas/isolamento & purificação , Fosfoproteínas/metabolismo , Arabidopsis/crescimento & desenvolvimento , Bacteriófago lambda/enzimologia , Técnicas de Cultura , Membranas Artificiais , Fenol/química , Monoéster Fosfórico Hidrolases/metabolismo , Fosforilação , Polivinil/químicaRESUMO
Precise content of gliadin (Glia) and glutenin (Glu) proteins in wheat grain are largely unknown despite their association with celiac disease, various allergies, and physical processing properties of wheat. Developing methods to quantitatively measure clinically relevant proteins could support advancement in understanding exposure thresholds and clinical study design. The aim of this study was to use a data-independent mass spectrometry (MS(E)) approach for quantifying gliadin and glutenin proteins in wheat grain. The biologically replicated analysis yielded concentrations for 34 gliadin and 22 glutenin proteins. The primary focus of this survey was on measuring celiac disease proteins and baker's asthma associated proteins along with the proteins associated with viscoelastic properties of wheat flour and grain texture. The technical coefficients of variation ranged from 0.12 to 1.39 and indicate that MS(E) proteomics is a reproducible quantitative method for the determination of gliadin and glutenin content in the highly complex matrix of protein extracts from wheat grain. This article is part of a Special Issue entitled: Translational Plant Proteomics.
Assuntos
Asma/genética , Doença Celíaca/genética , Gliadina/análise , Glutens/análise , Espectrometria de Massas/métodos , Triticum/química , ProteômicaRESUMO
A series of mono- or disaccharide-protein conjugates were prepared by amide bond formation. Incorporation efficiency of the aminosaccharides on bovine serum albumin was determined by colorimetry and matrix assisted laser desorption/ionization mass spectrometry. Study compares two amide bond coupling agents, 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride and 4-(4,6-dimethoxy-1,3,5-triazin-2-yl)-4-methylmorpholinium chloride. Paper demonstrates a practical usefulness of natural bovine serum albumin succinylation. Large number of its carboxyl groups results in its superior reactivity towards simple aminosaccharides.
Assuntos
Etildimetilaminopropil Carbodi-Imida/química , Glicoconjugados/química , Soroalbumina Bovina/química , Albumina Sérica/química , Animais , BovinosRESUMO
The incidence of hepatocellular carcinoma (HCC) in the United States is increasing and the increase is projected to continue for several decades. The overall survival of HCC patients is poor and treatments are not effective in part because most of the diagnoses come at a late stage. The development of new markers for detection of HCC would significantly improve patient prognosis. This paper describes identification of candidate markers previously reported in our serologic study of an Egyptian population by quantitative comparison of matrix assisted laser desorption ionization time of flight (MALDI-TOF) mass spectra. To identify these marker candidates, we performed LC-MS/MS sequencing that identified nine native peptides associated with HCC, including two reported previously. Four truncations of N terminus of complement C3f and a fibrinopeptide increased in control sera; two complement C4alpha peptides, a zyxin peptide, and a coagulation factor XIII peptide increased in cancer patient sera. We have also identified increased biliverdin diglucuronide in the sera of cancer patients. These peptides could potentially serve as markers of HCC following additional validation studies; however, association of similar peptides with other diseases and cancers dictates a very cautious approach.
Assuntos
Biomarcadores Tumorais/sangue , Carcinoma Hepatocelular/sangue , Neoplasias Hepáticas/sangue , Peptídeos/sangue , Sequência de Aminoácidos , Estudos de Casos e Controles , Cromatografia Líquida , Humanos , Dados de Sequência Molecular , Peso Molecular , Peptídeos/química , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Espectrometria de Massas em TandemRESUMO
OBJECTIVE: Aberrant glycosylation has been implicated in various types of cancers. Cancerous cells with altered glycosylation of their surface proteins shed such proteins into the circulating fluids. Glycomic profiling of such fluids shows the altered glycosylation. We performed glycomic profiling of serum from patients with no known disease, Barrett's without dysplasia, with high-grade dysplasia, and with esophageal adenocarcinoma in an attempt to delineate distinct differences in glycosylation among these groups. METHODS: Serum samples from patients with Barrett's metaplasia (N = 5), high-grade dysplasia (N = 11), and esophageal adenocarcinoma (N = 50) were collected; samples from 18 healthy volunteers were used as control. Serum N-glycans were enzymatically released and then applied to both C18 Sep-Pak (Waters, Milford, MA) cartridges and activated charcoal cartridges. N-glycans were permethylated and then spotted directly onto a matrix-assisted laser desorption ionization plate. Mass spectra were acquired using the Applied Biosystems 4800 MALDI TOF/TOF Analyzer (Applied Biosystems Inc, Framingham, Mass). The obtained matrix-assisted laser desorption ionization-mass spectrometry data were processed using DataExplorer files (Applied Biosystems Inc) listing m/z values and intensities. RESULTS: The intensities of 98 glycans were significantly different among the 3 groups; 26 of these corresponded to known glycan structures. Pairwise comparisons showed that 8 glycans were significantly different in all 3 pairwise comparisons. CONCLUSION: We demonstrated that comparative glycomic profiling of esophageal adenocarcinoma reveals a subset of glycans that can be selected as candidate biomarkers. These markers can differentiate normal from high-grade dysplasia, normal from esophageal adenocarcinoma, and high-grade dysplasia from esophageal adenocarcinoma. Further validation will be necessary to determine the clinical utility of these glycan biomarkers.