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1.
Nucleic Acids Res ; 52(12): 6945-6963, 2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38783095

RESUMO

Cellular senescence, a major driver of aging, can be stimulated by DNA damage, and is counteracted by the DNA repair machinery. Here we show that in p16INK4a-deficient cells, senescence induction by the environmental genotoxin B[a]P or ionizing radiation (IR) completely depends on p21CIP1. Immunoprecipitation-based mass spectrometry interactomics data revealed that during senescence induction and maintenance, p21CIP1 specifically inhibits CDK4 and thereby activates the DREAM complex. Genome-wide transcriptomics revealed striking similarities in the response induced by B[a]P and IR. Among the top 100 repressed genes 78 were identical between B[a]P and IR and 76 were DREAM targets. The DREAM complex transcriptionally silences the main proliferation-associated transcription factors E2F1, FOXM1 and B-Myb as well as multiple DNA repair factors. Knockdown of p21CIP1, E2F4 or E2F5 diminished both, repression of these factors and senescence. The transcriptional profiles evoked by B[a]P and IR largely overlapped with the profile induced by pharmacological CDK4 inhibition, further illustrating the role of CDK4 inhibition in genotoxic stress-induced senescence. Moreover, data obtained by live-cell time-lapse microscopy suggest the inhibition of CDK4 by p21CIP1 is especially important for arresting cells which slip through mitosis. Overall, we identified the p21CIP1/CDK4/DREAM axis as a master regulator of genotoxic stress-induced senescence.


Assuntos
Senescência Celular , Quinase 4 Dependente de Ciclina , Inibidor de Quinase Dependente de Ciclina p21 , Dano ao DNA , Proteínas Interatuantes com Canais de Kv , Senescência Celular/efeitos da radiação , Senescência Celular/genética , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Inibidor de Quinase Dependente de Ciclina p21/genética , Quinase 4 Dependente de Ciclina/metabolismo , Quinase 4 Dependente de Ciclina/genética , Humanos , Proteínas Interatuantes com Canais de Kv/metabolismo , Proteínas Interatuantes com Canais de Kv/genética , Radiação Ionizante , Reparo do DNA , Regulação da Expressão Gênica/efeitos da radiação , Proteínas Repressoras
2.
Trends Cancer ; 10(6): 481-485, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38503638

RESUMO

Pathogenic variants (PVs) in DNA repair-linked adult-onset cancer predisposition genes, including double heterozygosity, are increasingly identified in pediatric patients with cancer. Their role in childhood cancer, however, remains poorly understood. Integrating comprehensive tumor analysis is integral for understanding the contribution of such PVs in cancer development and personalized cancer care.


Assuntos
Idade de Início , Predisposição Genética para Doença , Neoplasias , Adulto , Criança , Humanos , Reparo do DNA , Neoplasias/genética , Neoplasias/patologia , Neoplasias/etiologia
3.
J Agric Food Chem ; 72(33): 18606-18618, 2024 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-39110027

RESUMO

Some germination is known to occur during the process of fermentation in cocoa beans. The impact of this biological process on the course of cocoa fermentation is not known and was thus investigated. In order to determine the impact of germination at the molecular level as well as on flavor, an untargeted metabolomics approach using Ultra Performance Liquid Chromatography-Electrospray Ionization-Time of Flight-Mass Spectrometry (UPLC-ESI-ToF-MS) with simultaneous acquisition of low- and high-collision energy mass spectra (MSe) was performed. Extracts of raw and germinated cocoa beans of the same origin were measured and compared for characteristic differences by unsupervised principal component analysis. OPLS-DA revealed 12-hydroxyjasmonic acid (HOJA) sulfate, (+)-catechin and (-)-epicatechin as most down-regulated compounds as well as two hydroxymethylglutaryl (HMG) glucosides A and B among others as decisive up-regulated compounds in the germinated material. Additionally, further HMG glucosides and 12-hydroxyjasmonic acid could be identified in cocoa for the first time by coelution with isolated and synthesized reference compounds. HOJA sulfate, which has been postulated in cocoa, and HOJA were revealed to impart bitter and astringent taste qualities.


Assuntos
Cacau , Germinação , Sementes , Cacau/química , Cacau/metabolismo , Cacau/crescimento & desenvolvimento , Sementes/química , Sementes/crescimento & desenvolvimento , Sementes/metabolismo , Cromatografia Líquida de Alta Pressão , Espectrometria de Massas por Ionização por Electrospray , Catequina/metabolismo , Catequina/análise , Paladar , Oxilipinas/metabolismo , Ciclopentanos/metabolismo
4.
J Agric Food Chem ; 72(31): 17524-17535, 2024 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-39074251

RESUMO

A recently published untargeted metabolomics approach toward marker compounds of cocoa germination revealed and identified 12-hydroxyjasmonic acid sulfate, (+)-catechin, and (-)-epicatechin as the most downregulated compounds and two hydroxymethylglutaryl glucosides (HMG gluc) A and B, among others, as the decisive upregulated compounds in the germinated material. These findings were quantitatively evaluated using ultrahigh-performance liquid chromatography-tandem mass spectrometry not only in previously examined sample material but also in a vastly expanded array of cocoa samples of different provenience and process and in cocoa products such as cocoa liquor and chocolate. Hereby, yields of newly identified HMG gluc derivatives could be determined in raw, fermented, germinated, and alternatively processed cocoa, and isomers of HMG gluc A and B could be established as key process indicators. Based on unsupervised clustering and supervised classification, models could identify germinated samples in testing sets consisting of raw, fermented, and germinated samples.


Assuntos
Cacau , Germinação , Sementes , Cacau/química , Cacau/metabolismo , Cacau/crescimento & desenvolvimento , Cacau/genética , Sementes/química , Sementes/crescimento & desenvolvimento , Sementes/metabolismo , Cromatografia Líquida de Alta Pressão , Espectrometria de Massas em Tandem , Catequina/metabolismo , Catequina/análise , Catequina/análogos & derivados , Metabolômica
5.
J Agric Food Chem ; 72(29): 16423-16437, 2024 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-39010731

RESUMO

A sensitive high-performance liquid chromatography-triple quadrupole mass spectrometry (HPLC-MS/MSMRM) method, leveraging both technique and internal calibration, was developed for the simultaneous and comprehensive quantitative analysis of 46 antioxidants and antioxidant precursors in different beer types without any cleanup procedure. Combined with their in vitro antioxidant activity, a dose-activity estimation exposed a group of 10 key antioxidants, namely, tryptophan, tyrosine, hordatine A, hordatine B, procyanidin B3, prodelphinidin B3, tachioside (3-methoxy-4-hydroxyphenyl-ß-d-glucopyranoside), (+)-catechin, tyrosol, and ferulic acid. To study the effect of antioxidants in spiking and aging studies, another liquid chromatography-MS (LC-MS)-based method was developed, monitoring markers for oxidation in beer. A positive effect of the antioxidants on the flavor stability at naturally relevant concentrations was shown by a slowing of oxygen-dependent aging reactions highlighted in beer storage trials under oxygen atmosphere. Thereby, a doubling of the natural concentration of all investigated antioxidants in beer revealed a limit inhibition of 67% on the degradation of cis-isocohumulone to hydroxy-cis-alloisocohumulone.


Assuntos
Antioxidantes , Cerveja , Oxirredução , Cerveja/análise , Antioxidantes/química , Antioxidantes/análise , Cromatografia Líquida de Alta Pressão , Espectrometria de Massas em Tandem
6.
J Agric Food Chem ; 2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38833300

RESUMO

The application of high-performance liquid chromatography-mass spectrometry (HPLC-MS/MS) revealed the origin and evolution of antioxidants during the brewing process of hopped and unhopped reference beer. As tachioside (3-methoxy-4-hydroxyphenyl-ß-d-glucopyranoside), arbutin (4-hydroxyphenyl-ß-d-glucopyranoside), and hordatines clearly increased during the fermentation step, the raw material barley was investigated as a source of the corresponding precursors. Therefore, 4-hydroxyphenyl-ß-d-glucopyranosyl-(1 → 6)-ß-d-glucopyranosyl-(1 → 6)-ß-d-glucopyranoside, 4-hydroxy-3-methoxyphenyl-ß-d-glucopyranosyl-(1 → 6)-ß-d-glucopyranoside, 4-hydroxy-3-methoxyphenyl-ß-d-glucopyranosyl-(1 → 6)-ß-d-glucopyranosyl-(1 → 6)-ß-d-glucopyranoside, and 4-hydroxy-2-methoxyphenyl-ß-d-glucopyranosyl-(1 → 6)-ß-d-glucopyranosyl-(1 → 6)-ß-d-glucopyranoside were isolated from barley for the first time, and identified using liquid chromatography-mass spectrometry (LC-MS) and one-dimensional/two-dimensional-nuclear magnetic resonance (1D/2D-NMR) experiments. Moreover, hordatine glucosides A, B, and C were isolated and identified from barley, and hordatine C glucoside was characterized for the first time. A fermentation model followed by HPLC-MS/MS analysis substantiated the release of tachioside from 4-hydroxy-3-methoxyphenyl-ß-d-glucopyranosyl-(1 → 6)-ß-d-glucopyranoside by Saccharomyces cerevisiae. Quantitation experiments monitoring the content in wheat, barley, and different barley malt types demonstrated a wide range of concentrations, providing a basis for further comprehensive investigations to optimize the antioxidant yield in beer to contribute to improved flavor stability.

7.
J Agric Food Chem ; 72(18): 10558-10569, 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38668637

RESUMO

As a traditional Thai condiment, Pla-ra is used to add flavor and richness to dishes. Nine treatment combinations of Pla-ra formulations created from 3 types of fish (Mor fish, Kradee fish, and Mor + Kradee fish) and 4 different carbohydrate sources (none, rice bran, roasted rice, and rice bran─roasted rice mixture) were studied through a 12 month fermentation period (1, 3, 5, 7, 8, 9, 10, 11, and 12 months). 16S rRNA Next Generation Sequencing (NGS) and LC-MS/MS techniques were used to analyze the microbial diversity and identify taste-enhancing peptides. Descriptive sensory analysis was performed on the extracts of the 108 Pla-ra samples mixed in a model broth. Koku perception and saltiness-enhancing attributes were clearly perceived and dominant in all samples, even though glutamyl peptides, including γ-Glu-Val-Gly, were found at subthreshold levels. The samples from mixed fish and Mor fish fermented with roasted ground rice and rice bran for 12 months had the most typical Pla-ra odors and tastes and had high taste-enhancing activities. NGS analysis revealed the presence of bacteria containing a large number of protease and aminopeptidase genes in the samples. Bacillus spp., Gallicola spp., and Proteiniclasticum spp. correlated well with the generation of glutamyl and arginyl peptides and typical odors in the samples. These results confirmed the typical sensory quality of Pla-ra depended on protein sources, carbohydrate sources, and bacteria communities. Further optimization of the microbial composition found could lead to the development of starter cultures to control and promote flavor development in fermented fish products.


Assuntos
Fermentação , Peixes , Aromatizantes , Microbiota , Peptídeos , Paladar , Animais , Feminino , Humanos , Masculino , Bactérias/classificação , Bactérias/genética , Bactérias/isolamento & purificação , Bactérias/metabolismo , Condimentos/análise , Condimentos/microbiologia , Alimentos Fermentados/análise , Alimentos Fermentados/microbiologia , Produtos Pesqueiros/análise , Produtos Pesqueiros/microbiologia , Peixes/microbiologia , Aromatizantes/química , Aromatizantes/metabolismo , Odorantes/análise , Oryza/química , Oryza/microbiologia , Oryza/metabolismo , Peptídeos/metabolismo , RNA Ribossômico 16S/genética , População do Sudeste Asiático , Tailândia , Adulto Jovem
8.
J Agric Food Chem ; 72(25): 14284-14293, 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38869215

RESUMO

Several compounds with taste-modulating properties have been investigated, improving the taste impression without having a pronounced intrinsic taste. The best-known representatives of umami taste-modulating compounds are ribonucleotides and their derivatives. Especially the thio derivatives showed high taste-modulating potential in structure-activity relationship investigations. Therefore, this study focuses on the formation of guanosine 5'-monophosphate derivatives consisting of Maillard-type generated compounds like the aroma-active thiols (2-methyl-3-furanthiol, 3-mercapto-2-pentanone, 2-furfurylthiol) and formaldehyde to gain insights into the potential of combinations of taste and aroma-active compounds. One literature-known (N2-(furfurylthiomethyl)-guanosine 5'-monophosphate) and three new derivatives (N2-(2-methyl-1-furylthiomethyl)-guanosine 5'-monophosphate, N2-((5-hydroxymethyl)-2-methyl-1-furylthiomethyl)-guanosine 5'-monophosphate, N2-((2-pentanon-1-yl)thiomethyl)-guanosine 5'-monophosphate) were successfully produced using green natural deep eutectic solvents and isolated, and their structures were completely elucidated. Besides the intrinsic taste properties, the kokumi and umami taste-modulating effects of the four derivatives were evaluated via psychophysical investigations, ranging from 19 to 22 µmol/L.


Assuntos
Aromatizantes , Guanosina Monofosfato , Reação de Maillard , Paladar , Guanosina Monofosfato/química , Humanos , Aromatizantes/química , Masculino , Feminino , Estrutura Molecular , Adulto , Adulto Jovem
9.
J Agric Food Chem ; 72(28): 15875-15889, 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-38957928

RESUMO

This study investigated the mechanism underlying the flavor improvement observed during fermentation of a pea protein-based beverage using Lactobacillus johnsonii NCC533. A combination of sensomics and sensoproteomics approach revealed that the fermentation process enriched or generated well-known basic taste ingredients, such as amino acids, nucleotides, organic acids, and dipeptides, besides six new taste-active peptide sequences that enhance kokumi and umami notes. The six new umami and kokumi enhancing peptides, with human recognition thresholds ranging from 0.046 to 0.555 mM, are produced through the degradation of Pisum sativum's storage protein. Our findings suggest that compounds derived from fermentation enhance umami and kokumi sensations and reduce bitterness, thus improving the overall flavor perception of pea proteins. In addition, the analysis of intraspecific variations in the proteolytic activity of L. johnsonii and the genome-peptidome correlation analysis performed in this study point at cell-wall-bound proteinases such as PrtP and PrtM as the key genes necessary to initiate the flavor improving proteolytic cascade. This study provides valuable insights into the molecular mechanisms underlying the flavor improvement of pea protein during fermentation and identifies potential future research directions. The results highlight the importance of combining fermentation and senso(proteo)mics techniques in developing tastier and more palatable plant-based protein products.


Assuntos
Fermentação , Aromatizantes , Lactobacillus , Proteínas de Ervilha , Pisum sativum , Paladar , Humanos , Proteínas de Ervilha/metabolismo , Proteínas de Ervilha/química , Lactobacillus/metabolismo , Lactobacillus/genética , Pisum sativum/química , Pisum sativum/metabolismo , Aromatizantes/metabolismo , Aromatizantes/química , Proteômica , Adulto , Masculino , Feminino , Adulto Jovem , Bebidas/análise , Bebidas/microbiologia
10.
J Agric Food Chem ; 72(26): 14830-14843, 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38888424

RESUMO

Beyond the key bitter compound kaempferol 3-O-(2‴-O-sinapoyl-ß-d-sophoroside) previously described in the literature (1), eight further bitter and astringent-tasting kaempferol glucosides (2-9) have been identified in rapeseed protein isolates (Brassica napus L.). The bitterness and astringency of these taste-active substances have been described with taste threshold concentrations ranging from 3.3 to 531.7 and 0.3 to 66.4 µmol/L, respectively, as determined by human sensory experiments. In this study, the impact of 1 and kaempferol 3-O-ß-d-glucopyranoside (8) on TAS2R-linked proton secretion by HGT-1 cells was analyzed by quantification of the intracellular proton index. mRNA levels of bitter receptors TAS2R3, 4, 5, 13, 30, 31, 39, 40, 43, 45, 46, 50 and TAS2R8 were increased after treatment with compounds 1 and 8. Using quantitative UHPLC-MS/MSMRM measurements, the concentrations of 1-9 were determined in rapeseed/canola seeds and their corresponding protein isolates. Depending on the sample material, compounds 1, 3, and 5-9 exceeded dose over threshold (DoT) factors above one for both bitterness and astringency in selected protein isolates. In addition, an increase in the key bitter compound 1 during industrial protein production (apart from enrichment) was observed, allowing the identification of the potential precursor of 1 to be kaempferol 3-O-(2‴-O-sinapoyl-ß-d-sophoroside)-7-O-ß-d-glucopyranoside (3). These results may contribute to the production of less bitter and astringent rapeseed protein isolates through the optimization of breeding and postharvest downstream processing.


Assuntos
Brassica napus , Glicosídeos , Quempferóis , Proteínas de Plantas , Receptores Acoplados a Proteínas G , Paladar , Humanos , Receptores Acoplados a Proteínas G/genética , Receptores Acoplados a Proteínas G/metabolismo , Brassica napus/química , Brassica napus/metabolismo , Brassica napus/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Proteínas de Plantas/química , Glicosídeos/química , Extratos Vegetais/química , Sementes/química , Sementes/metabolismo , Brassica rapa/química , Brassica rapa/metabolismo
11.
J Agric Food Chem ; 72(28): 15890-15905, 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-38953212

RESUMO

Pea-protein-based ingredients are gaining attention in the food industry due to their nutritional benefits and versatility, but their bitter, astringent, green, and beany off-flavors pose challenges. This study applied fermentation using microbial cultures to enhance the sensory qualities of pea-protein-based beverages. Using UHPLC-TOF-MS analyses along with sensory profile comparisons, microbial species such as Limosilactobacillus fermentum, Lactococcus lactis, Lactobacillus johnsonii, Lacticaseibacillus rhamnosus, and Bifidobacterium longum were preselected from an entire culture collection and found to be effective in improving the overall flavor impression by reducing bitter off-notes and enhancing aroma profiles. Notably, L. johnsonii NCC533 and L. fermentum NCC660 exhibited controlled proteolytic activities after 48 h of fermentation, enriching the matrix with taste-active amino acids, nucleotides, and peptides and improving umami and salty flavors while mitigating bitterness. This study has extended traditional volatile analyses, including nonvolatile metabolomic, proteomic, and sensory analyses and offering a detailed view of fermentation-induced biotransformations in pea-protein-based food. The results highlight the importance of combining comprehensive screening approaches and sensoproteomic techniques in developing tastier and more palatable plant-based protein products.


Assuntos
Fermentação , Aromatizantes , Proteínas de Ervilha , Pisum sativum , Paladar , Humanos , Proteínas de Ervilha/metabolismo , Proteínas de Ervilha/química , Pisum sativum/química , Pisum sativum/metabolismo , Pisum sativum/microbiologia , Aromatizantes/metabolismo , Aromatizantes/química , Feminino , Masculino , Adulto , Bebidas/análise , Bebidas/microbiologia
12.
Mol Nutr Food Res ; 68(8): e2300831, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38602198

RESUMO

SCOPE: The excretion of dietary odorants into urine and milk is evaluated and the impact of possible influencing factors determined. Furthermore, the metabolic relevance of conjugates for the excretion into milk is investigated. METHODS AND RESULTS: Lactating mothers (n = 20) are given a standardized curry dish and donated one milk and urine sample each before and 1, 2, 3, 4.5, 6, and 8 h after the intervention. The concentrations of nine target odorants in these samples are determined. A significant transition is observed for linalool into milk, as well as for linalool, cuminaldehyde, cinnamaldehyde, and eugenol into urine. Maximum concentrations are reached within 1 h after the intervention in the case of milk and within 2-3 h in the case of urine. In addition, the impact of glucuronidase treatment on odorant concentrations is evaluated in a sample subset of twelve mothers. Linalool, eugenol, and vanillin concentrations increased 3-77-fold in milk samples after treatment with ß-glucuronidase. CONCLUSION: The transfer profiles of odorants into milk and urine differ qualitatively, quantitatively, and in temporal aspects. More substances are transferred into urine and the transfer needs a longer period compared with milk. Phase II metabolites are transferred into urine and milk.


Assuntos
Acroleína/análogos & derivados , Monoterpenos Acíclicos , Benzaldeídos , Eugenol , Leite Humano , Odorantes , Humanos , Leite Humano/química , Feminino , Odorantes/análise , Eugenol/urina , Eugenol/metabolismo , Eugenol/análogos & derivados , Adulto , Benzaldeídos/urina , Monoterpenos Acíclicos/urina , Glucuronidase/metabolismo , Lactação , Acroleína/urina , Acroleína/metabolismo , Monoterpenos/urina
13.
Front Oncol ; 14: 1374592, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38817890

RESUMO

Purpose: The aim of this retrospective analysis was to determine if the response to preoperative radio(chemo)therapy is predictive for survival among patients with locally advanced rectal cancer and may act as a potential surrogate endpoint for disease free survival and overall survival. Results: Eight hundred seventy-eight patients from five centers were analyzed. There were 304 women and 574 men; the median age was 64.7 years. 77.6% and 22.4% of patients received neoadjuvant radiochemotherapy or short-course radiotherapy, resulting in a pathological complete response in 7.3%. T-downstaging and N-downstaging occurred in 50.5% and 37% of patients after neoadjuvant therapy. In patients with T-downstaging, the 10-year DFS and 10-year OS were 64.8% and 66.8% compared to 37.1% and 45.9% in patients without T-downstaging. N-downstaging resulted in 10-year DFS and 10-year OS in 56.2% and 62.5% compared to 47.3% and 52.3% without N-downstaging. Based on routinely evaluated clinical parameters, an absolute risk prediction calculator was generated for 5-year disease-free survival, and 5-year overall survival. Conclusion: T-downstaging and N-downstaging after neoadjuvant radiochemotherapy or short-course radiotherapy resulted in better DFS and OS compared to patients without response. Based on clinical parameters, 5-year DFS, and 5-year OS can be predicted using a prediction calculator.

14.
J Agric Food Chem ; 72(1): 1-3, 2024 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-38197191
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