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1.
Nature ; 557(7703): 112-117, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29695863

RESUMO

The linear ubiquitin chain assembly complex (LUBAC) is required for optimal gene activation and prevention of cell death upon activation of immune receptors, including TNFR1 1 . Deficiency in the LUBAC components SHARPIN or HOIP in mice results in severe inflammation in adulthood or embryonic lethality, respectively, owing to deregulation of TNFR1-mediated cell death2-8. In humans, deficiency in the third LUBAC component HOIL-1 causes autoimmunity and inflammatory disease, similar to HOIP deficiency, whereas HOIL-1 deficiency in mice was reported to cause no overt phenotype9-11. Here we show, by creating HOIL-1-deficient mice, that HOIL-1 is as essential for LUBAC function as HOIP, albeit for different reasons: whereas HOIP is the catalytically active component of LUBAC, HOIL-1 is required for LUBAC assembly, stability and optimal retention in the TNFR1 signalling complex, thereby preventing aberrant cell death. Both HOIL-1 and HOIP prevent embryonic lethality at mid-gestation by interfering with aberrant TNFR1-mediated endothelial cell death, which only partially depends on RIPK1 kinase activity. Co-deletion of caspase-8 with RIPK3 or MLKL prevents cell death in Hoil-1-/- (also known as Rbck1-/-) embryos, yet only the combined loss of caspase-8 with MLKL results in viable HOIL-1-deficient mice. Notably, triple-knockout Ripk3-/-Casp8-/-Hoil-1-/- embryos die at late gestation owing to haematopoietic defects that are rescued by co-deletion of RIPK1 but not MLKL. Collectively, these results demonstrate that both HOIP and HOIL-1 are essential LUBAC components and are required for embryogenesis by preventing aberrant cell death. Furthermore, they reveal that when LUBAC and caspase-8 are absent, RIPK3 prevents RIPK1 from inducing embryonic lethality by causing defects in fetal haematopoiesis.


Assuntos
Proteínas de Transporte/metabolismo , Morte Celular , Desenvolvimento Embrionário , Hematopoese , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitina/metabolismo , Animais , Proteínas de Transporte/química , Proteínas de Transporte/genética , Caspase 8/genética , Caspase 8/metabolismo , Morte Celular/genética , Perda do Embrião/genética , Desenvolvimento Embrionário/genética , Células Endoteliais/citologia , Feminino , Hematopoese/genética , Camundongos , Camundongos Endogâmicos C57BL , Domínios Proteicos , Proteínas Quinases/genética , Proteína Serina-Treonina Quinases de Interação com Receptores/deficiência , Receptores Tipo I de Fatores de Necrose Tumoral/metabolismo , Transdução de Sinais , Ubiquitina-Proteína Ligases/deficiência , Ubiquitina-Proteína Ligases/genética
2.
Digestion ; 105(3): 232-242, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38527451

RESUMO

INTRODUCTION: 5-aminosalicylic acid (5-ASA) is the first-line drug for the treatment of mild-to-moderate ulcerative colitis (UC). Three oral sustained-release formulations are often used. However, no unified view of their actual use in routine medical practice has been presented to date. METHODS: Using a health insurance claims database, we extracted patients with an initial diagnosis of mild-to-moderate UC during the period from December 1, 2017, to March 31, 2022. For the three types of oral 5-ASA formulation, we calculated and compared descriptive statistics of medication persistence rates (MPR), proportions of days covered (PDC), and adherence proportion (PDC ≥80%) in the extracted population. RESULTS: An oral 5-ASA formulation was used in combination with a topical preparation (cohort 1) in 899 patients, and oral 5-ASA was used alone (cohort 2) in 1,829 patients. In cohort 1, MPR at days 151-180 with concomitant use of topical formulation was significantly higher for the Multi Matrix System™ (MMX) formulation (65.2%) compared with that for pH-dependent formulation (51.7%, p < 0.025), while MPR tended to be higher for MMX than for the time-dependent formulation (56.4%, not significant). During days 151-180 after starting the oral formulation, MPR for MMX (66.7% and 65.8%) was higher than for pH-dependent (55.9% and 55.3%) and time-dependent (57.6% and 55.9%) formulations in cohorts 1 + 2 and 2, respectively. In cohort 1, there was a significant difference between MMX (68.3%) and pH-dependent (57.1%) formulations, but no significant difference was seen with time-dependent formulations (61.8%). In terms of the proportion of adherence until day 180, MMX was significantly better than the other formulations. CONCLUSION: The analyses of the three oral 5-ASA formulations suggested that both MPR and medication adherence were better for the MMX formulation than for time-dependent or pH-dependent formulations.


Assuntos
Anti-Inflamatórios não Esteroides , Colite Ulcerativa , Bases de Dados Factuais , Adesão à Medicação , Mesalamina , Humanos , Colite Ulcerativa/tratamento farmacológico , Mesalamina/administração & dosagem , Mesalamina/uso terapêutico , Adesão à Medicação/estatística & dados numéricos , Masculino , Feminino , Administração Oral , Pessoa de Meia-Idade , Adulto , Japão , Anti-Inflamatórios não Esteroides/administração & dosagem , Anti-Inflamatórios não Esteroides/uso terapêutico , Idoso , Preparações de Ação Retardada , Estudos Retrospectivos , Adulto Jovem , Administração Tópica , População do Leste Asiático
3.
EMBO J ; 36(9): 1147-1166, 2017 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-28258062

RESUMO

The linear ubiquitin chain assembly complex (LUBAC) is the only known E3 ubiquitin ligase which catalyses the generation of linear ubiquitin linkages de novo LUBAC is a crucial component of various immune receptor signalling pathways. Here, we show that LUBAC forms part of the TRAIL-R-associated complex I as well as of the cytoplasmic TRAIL-induced complex II In both of these complexes, HOIP limits caspase-8 activity and, consequently, apoptosis whilst being itself cleaved in a caspase-8-dependent manner. Yet, by limiting the formation of a RIPK1/RIPK3/MLKL-containing complex, LUBAC also restricts TRAIL-induced necroptosis. We identify RIPK1 and caspase-8 as linearly ubiquitinated targets of LUBAC following TRAIL stimulation. Contrary to its role in preventing TRAIL-induced RIPK1-independent apoptosis, HOIP presence, but not its activity, is required for preventing necroptosis. By promoting recruitment of the IKK complex to complex I, LUBAC also promotes TRAIL-induced activation of NF-κB and, consequently, the production of cytokines, downstream of FADD, caspase-8 and cIAP1/2. Hence, LUBAC controls the TRAIL signalling outcome from complex I and II, two platforms which both trigger cell death and gene activation.


Assuntos
Morte Celular , Receptores do Ligante Indutor de Apoptose Relacionado a TNF/metabolismo , Ligante Indutor de Apoptose Relacionado a TNF/metabolismo , Ativação Transcricional , Ubiquitina-Proteína Ligases/metabolismo , Linhagem Celular , Humanos
4.
Angew Chem Int Ed Engl ; 60(4): 2036-2041, 2021 01 25.
Artigo em Inglês | MEDLINE | ID: mdl-33044791

RESUMO

The transformation of glycals into 2,3-unsaturated glycosyl derivatives, reported by Ferrier in 1962, is supposed to involve an α,ß unsaturated glycosyl cation, an elusive ionic species that has still to be observed experimentally. Herein, while combination of TfOH and flow conditions failed to observe this ionic species, its extended lifetime in superacid solutions allowed its characterization by NMR-based structural analysis supported by DFT calculations. This allyloxycarbenium ion was further exploited in the Ferrier rearrangement to afford unsaturated nitrogen-containing C-aryl glycosides and C-alkyl glycosides under superacid and flow conditions, respectively.

5.
Anal Chem ; 91(4): 3125-3130, 2019 02 19.
Artigo em Inglês | MEDLINE | ID: mdl-30667211

RESUMO

We propose a highly selective, sensitive, accurate, and high-throughput bioanalysis method for bevacizumab utilizing an anti-idiotype DNA aptamer. With this method, bevacizumab in a plasma sample was reacted in a 96-well plate immobilized with the aptamer and further reacted with a protein A-HRP conjugate. The resulting HRP activity was colorimetrically detected using a microplate reader. The calibration curve of bevacizumab ranged from 0.05 to 5.0 µg/mL, and showed a good correlation coefficient ( r2 = 1.000). The limit of detection was 2.09 ng/mL. We also demonstrated both the possibility of highly sensitive detection using luminol chemiluminescence and the repeated use of affinity plates. The proposed method is applicable for planning optimal therapeutic programs and for an evaluation of the biological equivalencies in the development of biosimilars.


Assuntos
Aptâmeros de Nucleotídeos/química , Bevacizumab/sangue , Ensaio de Imunoadsorção Enzimática , Ensaios de Triagem em Larga Escala , Peroxidase do Rábano Silvestre/química , Proteína Estafilocócica A/química , Aptâmeros de Nucleotídeos/metabolismo , Peroxidase do Rábano Silvestre/metabolismo , Humanos , Proteína Estafilocócica A/metabolismo
6.
Molecules ; 24(5)2019 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-30823418

RESUMO

This study presents a simple, accurate, and selective bioanalytical method of bevacizumab detection from plasma samples based on aptamer affinity purification⁻high-temperature reversed-phased liquid chromatography (HT-RPLC) with fluorescence detection. Bevacizumab in plasma samples was purified using magnetic beads immobilized with an anti-idiotype DNA aptamer for bevacizumab. The purified bevacizumab was separated with HT-RPLC and detected with its native fluorescence. Using aptamer affinity beads, bevacizumab was selectively purified and detected as a single peak in the chromatogram. HT-RPLC achieved good separation for bevacizumab with a sharp peak within 10 min. The calibration curves of the two monoclonal antibodies ranged from 1 to 50 µg/mL and showed good correlation coefficients (r² > 0.999). The limit of detection (LOD) and lower limit of quantification (LLOQ) values for bevacizumab were 0.15 and 0.51 µg/mL, respectively. The proposed method was successfully applied to the bioanalysis of the plasma samples obtained from the patients with lung cancer and may be extended to plan optimal therapeutic programs and for the evaluation of biological equivalencies in the development of biosimilars.


Assuntos
Aptâmeros de Nucleotídeos , Neoplasias Pulmonares/sangue , Neoplasias Pulmonares/tratamento farmacológico , Idoso , Aptâmeros de Nucleotídeos/química , Aptâmeros de Nucleotídeos/isolamento & purificação , Bevacizumab/administração & dosagem , Bevacizumab/farmacocinética , Cromatografia Líquida de Alta Pressão , Cromatografia de Fase Reversa , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
7.
Immunol Rev ; 266(1): 190-207, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26085216

RESUMO

Linear ubiquitination is a post-translational protein modification recently discovered to be crucial for innate and adaptive immune signaling. The function of linear ubiquitin chains is regulated at multiple levels: generation, recognition, and removal. These chains are generated by the linear ubiquitin chain assembly complex (LUBAC), the only known ubiquitin E3 capable of forming the linear ubiquitin linkage de novo. LUBAC is not only relevant for activation of nuclear factor-κB (NF-κB) and mitogen-activated protein kinases (MAPKs) in various signaling pathways, but importantly, it also regulates cell death downstream of immune receptors capable of inducing this response. Recognition of the linear ubiquitin linkage is specifically mediated by certain ubiquitin receptors, which is crucial for translation into the intended signaling outputs. LUBAC deficiency results in attenuated gene activation and increased cell death, causing pathologic conditions in both, mice, and humans. Removal of ubiquitin chains is mediated by deubiquitinases (DUBs). Two of them, OTULIN and CYLD, are constitutively associated with LUBAC. Here, we review the current knowledge on linear ubiquitination in immune signaling pathways and the biochemical mechanisms as to how linear polyubiquitin exerts its functions distinctly from those of other ubiquitin linkage types.


Assuntos
Endopeptidases/metabolismo , Proteínas Supressoras de Tumor/metabolismo , Animais , Morte Celular , Enzima Desubiquitinante CYLD , Humanos , Imunidade , Camundongos , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , Complexos Multiproteicos , NF-kappa B/metabolismo , Processamento de Proteína Pós-Traducional , Transdução de Sinais , Ubiquitinação
8.
Hepatology ; 65(6): 1963-1978, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28120397

RESUMO

Linear ubiquitination is a key posttranslational modification that regulates immune signaling and cell death pathways, notably tumor necrosis factor receptor 1 (TNFR1) signaling. The only known enzyme complex capable of forming linear ubiquitin chains under native conditions to date is the linear ubiquitin chain assembly complex, of which the catalytic core component is heme-oxidized iron regulatory protein 2 ubiquitin ligase-1-interacting protein (HOIP). To understand the underlying mechanisms of maintenance of liver homeostasis and the role of linear ubiquitination specifically in liver parenchymal cells, we investigated the physiological role of HOIP in the liver parenchyma. To do so, we created mice harboring liver parenchymal cell-specific deletion of HOIP (HoipΔhep mice) by crossing Hoip-floxed mice with albumin-Cre mice. HOIP deficiency in liver parenchymal cells triggered tumorigenesis at 18 months of age preceded by spontaneous hepatocyte apoptosis and liver inflammation within the first month of life. In line with the emergence of inflammation, HoipΔhep mice displayed enhanced liver regeneration and DNA damage. In addition, consistent with increased apoptosis, HOIP-deficient hepatocytes showed enhanced caspase activation and endogenous formation of a death-inducing signaling complex which activated caspase-8. Unexpectedly, exacerbated caspase activation and apoptosis were not dependent on TNFR1, whereas ensuing liver inflammation and tumorigenesis were promoted by TNFR1 signaling. CONCLUSION: The linear ubiquitin chain assembly complex serves as a previously undescribed tumor suppressor in the liver, restraining TNFR1-independent apoptosis in hepatocytes which, in its absence, is causative of TNFR1-mediated inflammation, resulting in hepatocarcinogenesis. (Hepatology 2017;65:1963-1978).


Assuntos
Apoptose/efeitos dos fármacos , Hepatite/imunologia , Neoplasias Hepáticas/patologia , Fator de Necrose Tumoral alfa/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitina/farmacologia , Animais , Apoptose/fisiologia , Carcinogênese/patologia , Caspase 8/metabolismo , Morte Celular/efeitos dos fármacos , Modelos Animais de Doenças , Hepatite/patologia , Hepatócitos/metabolismo , Hepatócitos/patologia , Neoplasias Hepáticas/fisiopatologia , Camundongos , Camundongos Endogâmicos C57BL , Distribuição Aleatória , Valores de Referência , Células Tumorais Cultivadas , Ubiquitina-Proteína Ligases/deficiência , Ubiquitinação/efeitos dos fármacos
9.
Biochem Biophys Res Commun ; 457(3): 479-84, 2015 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-25603054

RESUMO

Derived from mature adipocytes, dedifferentiated fat (DFAT) cells represent a special group of multipotent cells. However, their phenotype and cellular nature remain unclear. Our study found that human DFAT cells adopted perivascular characteristics and behaviors. Flow cytometry and immunofluorescent staining revealed that human DFAT cells positively expressed markers highly related to perivascular cell lineages, such as CD140b, NG2 and desmin, but were negative for common endothelial markers, including CD31, CD34, and CD309. Furthermore, DFAT cells displayed vascular network formation ability in Matrigel, and they noticeably promoted and stabilized the vessel structures formed by human umbilical vascular endothelial cells (HUVECs) in vitro. These results provide novel evidence on the pericyte nature of human DFAT cells, further supporting the recent model for the perivascular origin of adult stem cells, in which tissue-specific progenitor cells in mesenchymal tissues associate with blood vessels, exhibiting perivascular characteristics and functions.


Assuntos
Adipócitos/citologia , Células-Tronco Adultas/citologia , Desdiferenciação Celular , Células-Tronco Multipotentes/citologia , Adipócitos/metabolismo , Adulto , Células-Tronco Adultas/metabolismo , Antígenos/metabolismo , Antígenos CD/metabolismo , Antígeno CD146/metabolismo , Células Cultivadas , Técnicas de Cocultura , Células Endoteliais da Veia Umbilical Humana , Humanos , Células-Tronco Multipotentes/metabolismo , Neovascularização Fisiológica , Fenótipo , Proteoglicanas/metabolismo , Receptor beta de Fator de Crescimento Derivado de Plaquetas/metabolismo
10.
Int Immunol ; 26(3): 139-47, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24215907

RESUMO

Salmon roe has a high allergic potency and often causes anaphylaxis in Japan. The major allergic protein of salmon roe is ß'-component, which is a 35kDa vitellogenin fragment consisting of two subunits. To elucidate structural information and immunological characteristics, ß'-component and the subunit components were purified from chum salmon (Onchorhincus keta) roe and vitellogenin-encoding mRNA was used to prepare ß'-component subunit-encoding cDNA. This was PCR-amplified, cloned and sequenced and the deduced amino acid sequence compared with partial sequences of ß'-component obtained by peptide mapping. The recombinant ß'-component subunit was produced by bacterial expression in Escherichia coli and its IgE-binding ability was measured by ELISA using the sera of a patient allergic to salmon roe. This was then compared with that of the native ß'-component with and without carboxymethylation. Following successful cloning of the cDNA encoding the ß'-component subunit, 170 amino acid residues were deduced and matched with the amino acid sequences of 121 and 88 residues in the 16kDa and 18kDa subunits, respectively. The sequences of both ß'-component subunits were almost identical, and the predicted secondary structure of the ß'-component showed a high content of ß-pleated sheets and no α-helices. There was no difference in IgE-binding ability between the native and recombinant ß'-component subunits at the same protein concentration, regardless of carboxymethylation. In conclusion, ß'-component is a homodimer protein composed of two isoform subunits having the same level of IgE-binding ability and, therefore, allergenic identity.


Assuntos
Alérgenos/metabolismo , Escherichia coli/genética , Hipersensibilidade Alimentar/imunologia , Fragmentos de Peptídeos/metabolismo , Proteínas Recombinantes/metabolismo , Alérgenos/genética , Alérgenos/imunologia , Sequência de Aminoácidos , Anafilaxia/etiologia , Animais , Criança , Pré-Escolar , Clonagem Molecular , Proteínas do Ovo/imunologia , Mapeamento de Epitopos , Proteínas de Peixes/genética , Proteínas de Peixes/imunologia , Proteínas de Peixes/metabolismo , Hipersensibilidade Alimentar/complicações , Humanos , Imunoglobulina E/metabolismo , Lactente , Japão , Masculino , Dados de Sequência Molecular , Oncorhynchus keta/imunologia , Fragmentos de Peptídeos/genética , Fragmentos de Peptídeos/imunologia , Ligação Proteica , Proteínas Recombinantes/genética , Proteínas Recombinantes/imunologia
11.
Biosci Biotechnol Biochem ; 79(9): 1518-27, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25884412

RESUMO

Salmon myofibrillar protein (Mf) was investigated as a source of edible anti-inflammatory products. Peptides produced by stepwise digestion of Mf (without carbohydrate) with pepsin and trypsin had little effect on the secretion of inflammation-related compounds from lipopolysaccharide-stimulated RAW 264.7 macrophage cells. However, peptides prepared from Mf conjugated with alginate oligosaccharide (AO; 19 µg/mg protein) (dMSA) through the Maillard reaction in the presence of sorbitol significantly reduced the secretion of the pro-inflammatory mediators nitric oxide, tumor necrosis factor (TNF)-α and interleukin (IL)-6, as well as mRNA expression of TNF-α, IL-6, inducible nitric oxide synthase and cyclooxygenase-2. Additionally, dMSA inhibited acute inflammation in a carrageenan-induced model of paw edema in mice, but had no effect on natural killer cell cytotoxic activity or macrophage phagocytosis. These results suggest that fish Mf conjugated with AO may be a potential food material with anti-inflammatory function.


Assuntos
Anti-Inflamatórios/administração & dosagem , Edema/tratamento farmacológico , Inflamação/tratamento farmacológico , Peptídeos/administração & dosagem , Alginatos/administração & dosagem , Alginatos/química , Animais , Anti-Inflamatórios/química , Carragenina/toxicidade , Edema/induzido quimicamente , Ácido Glucurônico/administração & dosagem , Ácido Glucurônico/química , Ácidos Hexurônicos/administração & dosagem , Ácidos Hexurônicos/química , Inflamação/induzido quimicamente , Inflamação/patologia , Macrófagos/efeitos dos fármacos , Macrófagos/patologia , Camundongos , Oligossacarídeos/administração & dosagem , Oligossacarídeos/química , Peptídeos/química , Salmão
12.
Odontology ; 102(2): 279-83, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23575885

RESUMO

The aim of this study was to examine defect depths and volumes at the resin composite-dentin (R/D) interface after air polishing with different particles and spray angles. Samples were 54 dentin specimens that were formed in saucer-shaped cavities filled with resin composite. Each specimen was air polished with either sodium bicarbonate (NaHCO3) or one of two glycine (Gly) powders. The air polisher was set at angles of 90° to the interface and at 45° to the interface from both the dentin and resin composite sides. Air polishing with Gly powder produced defects with less depth and volume than NaHCO3 powder (p < 0.05). Air polishing with a spray angle of 45° to the interface from the resin composite side produced fewer defects (p < 0.05) than polishing from the dentin side. Air polishing to the R/D interface from the resin composite side produced fewer defects to the interface because the hardness of the resin composite was higher than that of dentin.


Assuntos
Resinas Compostas , Polimento Dentário , Dentina , Humanos
13.
Food Funct ; 15(7): 3629-3639, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38482590

RESUMO

Inflammation and oxidative stress contribute to noncommunicable diseases (NCDs), with macrophages playing pivotal roles. Glycated collagen through Maillard-type glycation holds promise for enhancing anti-inflammatory properties, but its mechanism remains unclear. This study investigates the cellular mechanism and aims to contribute to expanding collagen utilization. Collagen was glycated with alginate oligosaccharide (AO) and glucose (Glc: as a comparative case) at 60 °C and 35% relative humidity for up to 24 h (C-AO and C-Glc, respectively). The anti-inflammatory activities of both C-AO and C-Glc were evaluated using an LPS-stimulated macrophage model. 18 h AO-glycated collagen (C-AO18 h) was found to significantly reduce the production of nitric oxide and proinflammatory cytokines (TNF-α), interleukin-6 (IL-6), and interleukin-1ß (IL-1ß). In contrast, C-Glc did not exhibit enhanced anti-inflammatory activity during any of the glycation periods. The enhanced anti-inflammatory activity of C-AO18 h was attributed to its downregulating effect on LPS receptors (toll-like receptor 4, Tlr4; cluster of differentiation 14, Cd14) and myeloid differentiation primary response 88 (Myd88) mRNA expression, with suppression in receptor expression resulting in decreased phagocytic ability of macrophages against E. coli. In addition, compared with intact collagen, C-AO18 h exhibited improved antioxidant activity in the LPS-stimulated macrophage model, as it significantly upregulated superoxide dismutase (SOD) and catalase (CAT) activities while reducing malondialdehyde (MDA) levels. Overall, this study contributes to the development of collagen-based functional foods for mitigating inflammation and oxidative stress in NCDs.


Assuntos
Alginatos , Lipopolissacarídeos , Humanos , Lipopolissacarídeos/farmacologia , Alginatos/farmacologia , Alginatos/uso terapêutico , Escherichia coli/metabolismo , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Macrófagos/metabolismo , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Citocinas/metabolismo , Estresse Oxidativo , Antioxidantes/farmacologia
14.
Nat Commun ; 15(1): 4873, 2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38871696

RESUMO

In biosynthesis multiple kinds of reactive intermediates are generated, transported, and reacted across different parts of organisms, enabling highly sophisticated synthetic reactions. Herein we report a convergent synthetic approach, which utilizes dual intermediates of cationic and carbanionic species in a single step, hinted at by the ideal reaction conditions. By reactions of unsaturated precursors, such as enamines, with a superacid in a flow microreactor, cationic species, such as iminium ions, are generated rapidly and irreversibly, and before decomposition, they are transported to react with rapidly and independently generated carbanions, enabling direct C-C bond formation. Taking advantage of the reactivity of these double reactive intermediates, the reaction take place within a few seconds, enabling synthetic reactions which are not applicable in conventional reactions.

15.
Food Chem ; 398: 133876, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-35969990

RESUMO

Terasi is a fermented shrimp paste in Indonesia. We examined the effect of the Terasi manufacturing process on the abundance of the allergen tropomyosin (TM) and its IgG/IgE-binding ability. Terasi was produced from three shrimps, Akiami (Acetes japonicus), Okiami (Euphausia pacifica), and Isazaami (Neomysis awatchensis). Protein degradation and TM IgE-binding activity were examined by immunoblotting using anti-TM rabbit IgG and competitive enzyme-linked immunosorbent assays using shrimp-allergic patients' sera. The processing caused TM degradation, and the IgG-specific response in Akiami meat disappeared at the second fermentation step but remained in both Okiami and Isazaami Terasi. In contrast, TM IgE-binding in all meats decreased gradually during manufacturing and nearly completely disappeared in Akiami Terasi. Conclusively, Terasi production is an effective manufacturing process to reduce the IgE-binding ability of TM, and Terasi can be recognized as a low allergenic seafood when produced under an appropriate manufacturing condition.


Assuntos
Decápodes , Alimentos Fermentados , Hipersensibilidade Alimentar , Penaeidae , Alérgenos/metabolismo , Animais , Crustáceos/metabolismo , Decápodes/metabolismo , Imunoglobulina E/metabolismo , Imunoglobulina G/metabolismo , Indonésia , Penaeidae/metabolismo , Coelhos , Alimentos Marinhos , Tropomiosina/metabolismo
16.
Food Chem ; 407: 135162, 2023 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-36525806

RESUMO

The role of carboxyl group in uronic acid in enhancing the anti-inflammatory activity of fish myofibrillar protein (Mf) was investigated, when lyophilized Mf was reacted with various reducing sugars at 60 °C and 35% relative humidity through the Maillard reaction. After pepsin and trypsin digestion, the anti-inflammatory activity was evaluated by measuring the secretions of tumor necrosis factor-α, interleukin-6, interleukin-1ß, and nitric oxide in lipopolysaccharide-stimulated RAW 264.7 macrophage. The anti-inflammatory activity of Mf was not affected by glycation with glucose or galactose, whereas strongly enhanced by glycation with uronic acid-type reducing sugars: glucuronic acid, galacturonic acid, and alginate oligosaccharide. These results indicate that the presence of carboxyl group in reducing sugar is important for enhancing the anti-inflammatory activity of Mf. This study also shows that the enhanced effect could depend upon the number of carboxyl group in bound reducing sugar.


Assuntos
Reação de Maillard , Açúcares , Animais , Ácidos Urônicos , Oligossacarídeos , Anti-Inflamatórios/farmacologia
17.
Anal Sci ; 39(11): 1805-1811, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37660341

RESUMO

We report on the development of a versatile and accurate bioanalytical method for bevacizumab using a pretreatment method combining affinity purification with anti-idiotypic DNA aptamers and centrifugal ultrafiltration concentration, followed by liquid chromatography (LC)-fluorescence analysis. An affinity purification method using Sepharose beads as an affinity support removed immunoglobulin G and a large amount of coexisting substances in the serum sample. Purified bevacizumab was separated as a single peak by conventional LC and detected fluorometrically, showing good linearity (R2 = 0.999) in the range of 5-200 µg/mL, sufficient to analyze bevacizumab concentrations in the blood of bevacizumab-treated patients. By combining this purification method with a concentration method using a centrifugal filtration device that inhibits non-specific adsorption of bevacizumab, the quantitative range was reduced by a factor of 10 while showing good linearity (R2 = 0.999) in the 0.5-20 µg/mL range. The developed analytical method is expected to be used not only for general bioanalysis of therapeutic mAbs in clinical settings, but also for next-generation antibody drugs that show drug efficacy at low concentrations and for analysis of trace samples.

18.
Foods ; 11(15)2022 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-35954140

RESUMO

To improve the antioxidant activity of collagen molecules using Maillard-type glycation, the relation between antioxidant activity and progress indexes for the Maillard reaction must be understood. In this study, lyophilized tilapia scale collagen was mixed with a half weight of alginate oligosaccharide (AO) or glucose and incubated at 60 °C and 35% relative humidity for up to 18 h to produce the Maillard-type glycated collagen (C-AO and C-Glu, respectively). As glycation progressed, the amount of conjugated sugar coupled with UV-vis absorbance at 294 nm and 420 nm increased more rapidly in C-Glu than in C-AO, and the available lysine decreased rapidly in C-Glu compared with C-AO. The early-to-middle- and late-stage products of the Maillard reaction were involved in enhanced antioxidant activity of digested C-AO and digested C-Glu, respectively. Additionally, C-AO acquired the antioxidant activity without marked available lysine loss. The cytoprotective effect of collagen in H2O2-induced damage was enhanced by glycation, achieved by reducing malondialdehyde content and increasing superoxide dismutase and catalase activities. These results indicate that AO is an excellent reducing sugar that enhances the health benefits of collagen without excessive loss of lysine, which is a nutritional problem of the Maillard-type glycation.

19.
Adv Ther ; 39(11): 4892-4909, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36048405

RESUMO

INTRODUCTION: Although several studies suggest beneficial effects of low-dose estrogen-progestins (LEPs) and progestins on dysmenorrhea in Japanese women, the difference in efficacy between drugs remains unknown. METHODS: We identified studies by searching the MEDLINE, Cochrane Library, and ICHUSHI databases and included randomized controlled trials (RCTs) that used total dysmenorrhea score and visual analogue scale (VAS) as outcome measures to evaluate LEPs and progestins for primary and secondary dysmenorrhea. We analyzed results by meta-analysis and network meta-analysis (NMA). RESULTS: We identified 10 articles on eight RCTs and included seven drugs (six LEPs and one progestin, i.e., dienogest) and placebo in the analysis. Meta-analysis showed improvements in total dysmenorrhea score and VAS for almost all drugs compared with placebo. In NMA, VAS in secondary dysmenorrhea improved more with dienogest than with norethisterone/ethinylestradiol (mean difference - 25.84 [95% CrI - 44.46 to - 7.15]). In the comparison of administration regimens, VAS improved more with progestin-continuous than LEP-cyclic and the surface under the cumulative ranking (SUCRA) of LEP-extended and progestin-continuous appeared to be higher than that of LEP-cyclic. CONCLUSIONS: We confirmed that LEPs and dienogest are effective for primary and secondary dysmenorrhea and suggest that continuous regimens may be more effective than cyclic regimens in improving outcomes.


Assuntos
Dismenorreia , Gastroenteropatias , Dismenorreia/tratamento farmacológico , Estrogênios/uso terapêutico , Feminino , Humanos , Japão , Metanálise em Rede , Noretindrona/uso terapêutico , Progestinas/uso terapêutico
20.
Biosens Bioelectron ; 203: 114027, 2022 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-35114463

RESUMO

Therapeutic monoclonal antibodies (mAbs) are successful biomedicines; however, evaluation of their pharmacokinetics and pharmacodynamics demands highly specific discrimination from human immunoglobulin G naturally present in the blood. Here, we developed a novel anti-idiotype aptamer (termed A14#1) with extraordinary specificity against the anti-vascular endothelial growth factor therapeutic mAb, bevacizumab. Structural analysis of the antibody-aptamer complex showed that several bases of A14#1 recognized only the complementarity determining region (CDR) of bevacizumab, thereby contributing to its extraordinary specificity. As the CDR of bevacizumab is predicted to be highly positively charged under mildly acidic conditions and that DNA is negatively charged, the affinity of A14#1 to bevacizumab markedly increased at pH 4.7 (KD = 44 pM) than at pH 7.4 (KD = 12 nM). A14#1-based electrochemical detection method capable of detecting 31 pM of bevacizumab at pH 4.7 was thus developed. A14#1 could be potentially useful for therapeutic drug measurement as a novel ligand of bevacizumab.


Assuntos
Aptâmeros de Nucleotídeos , Técnicas Biossensoriais , Anticorpos Monoclonais , Afinidade de Anticorpos , Aptâmeros de Nucleotídeos/química , Regiões Determinantes de Complementaridade/química , Regiões Determinantes de Complementaridade/genética , Humanos , Concentração de Íons de Hidrogênio
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