Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 25.798
Filtrar
1.
Microb Biotechnol ; 17(4): e14441, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38568774

RESUMO

Rhizoctonia solani is a polyphagous necrotrophic fungal pathogen that causes sheath blight disease in rice. It deploys effector molecules as well as carbohydrate-active enzymes and enhances the production of reactive oxygen species for killing host tissues. Understanding R. solani ability to sustain growth under an oxidative-stress-enriched environment is important for developing disease control strategies. Here, we demonstrate that R. solani upregulates methionine biosynthetic genes, including Rs_MET13 during infection in rice, and double-stranded RNA-mediated silencing of these genes impairs the pathogen's ability to cause disease. Exogenous treatment with methionine restores the disease-causing ability of Rs_MET13-silenced R. solani and facilitates its growth on 10 mM H2O2-containing minimal-media. Notably, the Rs_MsrA gene that encodes methionine sulfoxide reductase A, an antioxidant enzyme involved in the repair of oxidative damage of methionine, is upregulated upon H2O2 treatment and also during infection in rice. Rs_MsrA-silenced R. solani is unable to cause disease, suggesting that it is important for the repair of oxidative damage in methionine during host colonization. We propose that spray-induced gene silencing of Rs_MsrA and designing of antagonistic molecules that block MsrA activity can be exploited as a drug target for effective control of sheath blight disease in rice.


Assuntos
Metionina Sulfóxido Redutases , Oryza , Rhizoctonia , Oryza/microbiologia , Metionina , Peróxido de Hidrogênio/farmacologia , Racemetionina/farmacologia , Doenças das Plantas/microbiologia
2.
Nat Commun ; 15(1): 2931, 2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-38575566

RESUMO

Cystathionine beta-synthase (CBS) is an essential metabolic enzyme across all domains of life for the production of glutathione, cysteine, and hydrogen sulfide. Appended to the conserved catalytic domain of human CBS is a regulatory domain that modulates activity by S-adenosyl-L-methionine (SAM) and promotes oligomerisation. Here we show using cryo-electron microscopy that full-length human CBS in the basal and SAM-bound activated states polymerises as filaments mediated by a conserved regulatory domain loop. In the basal state, CBS regulatory domains sterically block the catalytic domain active site, resulting in a low-activity filament with three CBS dimers per turn. This steric block is removed when in the activated state, one SAM molecule binds to the regulatory domain, forming a high-activity filament with two CBS dimers per turn. These large conformational changes result in a central filament of SAM-stabilised regulatory domains at the core, decorated with highly flexible catalytic domains. Polymerisation stabilises CBS and reduces thermal denaturation. In PC-3 cells, we observed nutrient-responsive CBS filamentation that disassembles when methionine is depleted and reversed in the presence of SAM. Together our findings extend our understanding of CBS enzyme regulation, and open new avenues for investigating the pathogenic mechanism and therapeutic opportunities for CBS-associated disorders.


Assuntos
Cistationina beta-Sintase , Metionina , Humanos , Cistationina beta-Sintase/metabolismo , Microscopia Crioeletrônica , S-Adenosilmetionina/metabolismo , Domínio Catalítico
3.
Int J Mol Sci ; 25(7)2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38612469

RESUMO

Dietary methionine restriction (MetR) offers an integrated set of beneficial health effects, including delaying aging, extending health span, preventing fat accumulation, and reducing oxidative stress. This study aimed to investigate whether MetR exerts entero-protective effects by modulating intestinal flora, and the effect of MetR on plasma metabolites in rats. Rats were fed diets containing 0.86% methionine (CON group) and 0.17% methionine (MetR group) for 6 weeks. Several indicators of inflammation, gut microbiota, plasma metabolites, and intestinal barrier function were measured. 16S rRNA gene sequencing was used to analyze the cecal microbiota. The MetR diet reduced the plasma and colonic inflammatory factor levels. The MetR diet significantly improved intestinal barrier function by increasing the mRNA expression of tight junction proteins, such as zonula occludens (ZO)-1, claudin-3, and claudin-5. In addition, MetR significantly increased the levels of short-chain fatty acids (SCFAs) by increasing the abundance of SCFAs-producing Erysipclotxichaceae and Clostridium_sensu_stricto_1 and decreasing the abundance of pro-inflammatory bacteria Proteobacteria and Escherichia-Shigella. Furthermore, MetR reduced the plasma levels of taurochenodeoxycholate-7-sulfate, taurocholic acid, and tauro-ursodeoxycholic acid. Correlation analysis identified that colonic acetate, total colonic SCFAs, 8-acetylegelolide, collettiside I, 6-methyladenine, and cholic acid glucuronide showed a significant positive correlation with Clostridium_sensu_stricto_1 abundance but a significant negative correlation with Escherichia-Shigella and Enterococcus abundance. MetR improved gut health and altered the plasma metabolic profile by regulating the gut microbiota in rats.


Assuntos
Microbioma Gastrointestinal , Metionina , Animais , Ratos , RNA Ribossômico 16S/genética , Racemetionina , Metabolômica
4.
Nutrients ; 16(7)2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38613029

RESUMO

Methionine dependence is a characteristic of most cancer cells where they are unable to proliferate when the essential amino acid methionine is replaced with its precursor homocysteine in the growing media. Normal cells, on the other hand, thrive under these conditions and are referred to as methionine-independent. The reaction that adds a methyl group from 5-methyltetrahydrofolate to homocysteine to regenerate methionine is catalyzed by the enzyme methionine synthase with the cofactor cobalamin (vitamin B12). However, decades of research have shown that methionine dependence in cancer is not due to a defect in the activity of methionine synthase. Cobalamin metabolism has been tied to the dependent phenotype in rare cell lines. We have identified a human colorectal cancer cell line in which the cells regain the ability to proliferation in methionine-free, L-homocystine-supplemented media when cyanocobalamin is supplemented at a level of 1 µg/mL. In human SW48 cells, methionine replacement with L-homocystine does not induce any measurable increase in apoptosis or reactive oxygen species production in this cell line. Rather, proliferation is halted, then restored in the presence of cyanocobalamin. Our data show that supplementation with cyanocobalamin prevents the activation of the integrated stress response (ISR) in methionine-deprived media in this cell line. The ISR-associated cell cycle arrest, characteristic of methionine-dependence in cancer, is also prevented, leading to the continuation of proliferation in methionine-deprived SW48 cells with cobalamin. Our results highlight differences between cancer cell lines in the response to cobalamin supplementation in the context of methionine dependence.


Assuntos
Neoplasias Colorretais , Metionina , Humanos , Metionina/farmacologia , 5-Metiltetra-Hidrofolato-Homocisteína S-Metiltransferase , Vitamina B 12/farmacologia , Homocistina , Racemetionina , Linhagem Celular , Homocisteína , Neoplasias Colorretais/tratamento farmacológico
5.
Metabolomics ; 20(2): 36, 2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38446263

RESUMO

INTRODUCTION: Sepsis is a highly morbid condition characterized by multi-organ dysfunction resulting from dysregulated inflammation in response to acute infection. Mitochondrial dysfunction may contribute to sepsis pathogenesis, but quantifying mitochondrial dysfunction remains challenging. OBJECTIVE: To assess the extent to which circulating markers of mitochondrial dysfunction are increased in septic shock, and their relationship to severity and mortality. METHODS: We performed both full-scan and targeted (known markers of genetic mitochondrial disease) metabolomics on plasma to determine markers of mitochondrial dysfunction which distinguish subjects with septic shock (n = 42) from cardiogenic shock without infection (n = 19), bacteremia without sepsis (n = 18), and ambulatory controls (n = 19) - the latter three being conditions in which mitochondrial function, proxied by peripheral oxygen consumption, is presumed intact. RESULTS: Nine metabolites were significantly increased in septic shock compared to all three comparator groups. This list includes N-formyl-L-methionine (f-Met), a marker of dysregulated mitochondrial protein translation, and N-lactoyl-phenylalanine (lac-Phe), representative of the N-lactoyl-amino acids (lac-AAs), which are elevated in plasma of patients with monogenic mitochondrial disease. Compared to lactate, the clinical biomarker used to define septic shock, there was greater separation between survivors and non-survivors of septic shock for both f-Met and the lac-AAs measured within 24 h of ICU admission. Additionally, tryptophan was the one metabolite significantly decreased in septic shock compared to all other groups, while its breakdown product kynurenate was one of the 9 significantly increased. CONCLUSION: Future studies which validate the measurement of lac-AAs and f-Met in conjunction with lactate could define a sepsis subtype characterized by mitochondrial dysfunction.


Assuntos
Doenças Mitocondriais , Sepse , Choque Séptico , Humanos , Aminoácidos , N-Formilmetionina , Metabolômica , Metionina , Ácido Láctico , Racemetionina
6.
Sci Rep ; 14(1): 5555, 2024 03 06.
Artigo em Inglês | MEDLINE | ID: mdl-38448604

RESUMO

Methionine (Met) rich diet inducing oxidative stress is reported to alter many organs. Proteasome as a regulator of oxidative stress can be targeted. This study was performed to investigate if excessive methionine supplementation causes hepatotoxicity related to proteasome dysfunction under endogenous oxidative stress in rats. Male Wistar albino rats (n = 16) were divided into controls and treated groups. The treated rats (n = 08) received orally L-methionine (1 g/kg/day) for 21 days. Total homocysteine (tHcy), total oxidant status (TOS), total antioxidant status (TAS), hepatic enzymes levels: aspartate aminotransferase (AST), alanine aminotransferase (ALT), lactate dehydrogenase (LDH), alkaline phosphatase (ALP), with total bilirubin (TBil), albumin (Alb), and C-reactive protein (CRP) were determined in plasma by biochemical assays. Liver supernatants were used for malondialdehyde (MDA), protein carbonyls (PC), glutathione (GSH), catalase (CAT), superoxide dismutase (SOD), glutathione peroxidase (GPx), 20S proteasome activities and their subunits expression, tumor necrosis factor-α (TNF-α), and interleukin 6 (IL-6) evaluation by appropriate methods and light microscopy for liver histological examination. Methionine treatment increased homocysteine, TOS, oxidative stress index (OSI), MDA and PC but decreased TAS, GSH, CAT, SOD, GPx with the 20S proteasome activities and their ß subunits expression. Liver proteins: AST, ALT, LDH, ALP, TBil and CRP were increased but Alb was decreased. Liver histology was also altered. An increase in liver TNF-α and IL-6 levels were observed. These findings indicated that methionine supplementation associated oxidative stress and proteasome dysfunction, caused hepatotoxicity and inflammation in rat. Further investigations should be to better understand the relation between methionine, oxidative stress, proteasome, and liver injuries.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas , Metionina , Masculino , Animais , Ratos , Ratos Wistar , Complexo de Endopeptidases do Proteassoma , Interleucina-6 , Fator de Necrose Tumoral alfa , Racemetionina , Dieta , Estresse Oxidativo , Antioxidantes , Proteína C-Reativa , Albuminas , Homocisteína , Superóxido Dismutase
7.
Food Microbiol ; 120: 104467, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38431319

RESUMO

The luxS mutant strains of Shewanella putrefaciens (SHP) were constructed to investigate the regulations of gene luxS in spoilage ability. The potential regulations of AI-2 quorum sensing (QS) system and activated methyl cycle (AMC) were studied by analyzing the supplementation roles of key circulating substances mediated via luxS, including S-adenosylmethionine (SAM), S-adenosylhomocysteine (SAH), methionine (Met), homocysteine (Hcy) and 4,5-dihydroxy-2,3-pentanedione (DPD). Growth experiments revealed that the luxS deletion led to certain growth limitations of SHP, which were associated with culture medium and exogenous additives. Meanwhile, the decreased biofilm formation and diminished hydrogen sulfide (H2S) production capacity of SHP were observed after luxS deletion. The relatively lower total volatile base nitrogen (TVB-N) contents and higher sensory scores of fish homogenate with luxS mutant strain inoculation also indicated the weaker spoilage-inducing effects after luxS deletion. However, these deficiencies could be offset with the exogenous supply of circulating substances mentioned above. Our findings suggested that the luxS deletion would reduce the spoilage ability of SHP, which was potentially attributed to the disorder of AMC and AI-2 QS system.


Assuntos
Percepção de Quorum , Shewanella putrefaciens , Animais , Percepção de Quorum/genética , Shewanella putrefaciens/genética , Shewanella putrefaciens/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Metionina/genética , Metionina/metabolismo , Biofilmes , Regulação Bacteriana da Expressão Gênica
9.
Gut Microbes ; 16(1): 2300847, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38439565

RESUMO

Dietary patterns and corresponding gut microbiota profiles are associated with various health conditions. A diet rich in polyphenols, primarily plant-based, has been shown to promote the growth of probiotic bacteria in the gastrointestinal tract, subsequently reducing the risk of metabolic disorders in the host. The beneficial effects of these bacteria are largely due to the specific metabolites they produce, such as short-chain fatty acids and membrane proteins. In this study, we employed a metabolomics-guided bioactive metabolite identification platform that included bioactivity testing using in vitro and in vivo assays to discover a bioactive metabolite produced from probiotic bacteria. Through this approach, we identified 5'-methylthioadenosine (MTA) as a probiotic bacterial-derived metabolite with anti-obesity properties. Furthermore, our findings indicate that MTA administration has several regulatory impacts on liver functions, including modulating fatty acid synthesis and glucose metabolism. The present study elucidates the intricate interplay between dietary habits, gut microbiota, and their resultant metabolites.


Assuntos
Desoxiadenosinas , Microbioma Gastrointestinal , Doenças Metabólicas , Tionucleosídeos , Humanos , Metionina , Bifidobacterium , Racemetionina
10.
Biotechnol J ; 19(3): e2300650, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38479990

RESUMO

S-Adenosyl-L-methionine (SAM) is a substrate for many enzyme-catalyzed reactions and provides methyl groups in numerous biological methylations, and thus has vast applications in the agriculture and medical field. Saccharomyces cerevisiae has been engineered as a platform with significant potential for producing SAM, but the current production has room for improvement. Thus, a method that consists of a series of metabolic engineering strategies was established in this study. These strategies included enhancing SAM synthesis, increasing ATP supply, down-regulating SAM metabolism, and down-regulating competing pathway. After combinatorial metabolic engineering, Bayesian optimization was conducted on the obtained strain C262P6S to optimize the fermentation medium. A final yield of 2972.8 mg·L-1 at 36 h with 29.7% of the L-Met conversion rate in the shake flask was achieved, which was 26.3 times higher than that of its parent strain and the highest reported production in the shake flask to date. This paper establishes a feasible foundation for the construction of SAM-producing strains using metabolic engineering strategies and demonstrates the effectiveness of Bayesian optimization in optimizing fermentation medium to enhance the generation of SAM.


Assuntos
Metionina , S-Adenosilmetionina , Metionina/metabolismo , S-Adenosilmetionina/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Engenharia Metabólica/métodos , Teorema de Bayes , Fermentação , Racemetionina/metabolismo
11.
J Am Chem Soc ; 146(10): 6493-6505, 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38426440

RESUMO

PylB is a radical S-adenosyl-l-methionine (SAM) enzyme predicted to convert l-lysine into (3R)-3-methyl-d-ornithine, a precursor in the biosynthesis of the 22nd proteogenic amino acid pyrrolysine. This protein highly resembles that of the radical SAM tyrosine and tryptophan lyases, which activate their substrate by abstracting a H atom from the amino-nitrogen position. Here, combining in vitro assays, analytical methods, electron paramagnetic resonance spectroscopy, and theoretical methods, we demonstrated that instead, PylB activates its substrate by abstracting a H atom from the Cγ position of l-lysine to afford the radical-based ß-scission. Strikingly, we also showed that PylB catalyzes the reverse reaction, converting (3R)-3-methyl-d-ornithine into l-lysine and using catalytic amounts of the 5'-deoxyadenosyl radical. Finally, we identified significant in vitro production of 5'-thioadenosine, an unexpected shunt product that we propose to result from the quenching of the 5'-deoxyadenosyl radical species by the nearby [Fe4S4] cluster.


Assuntos
Metionina , Ornitina/análogos & derivados , S-Adenosilmetionina , S-Adenosilmetionina/metabolismo , Lisina , Racemetionina , Espectroscopia de Ressonância de Spin Eletrônica
12.
Biotechnol J ; 19(3): e2300579, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38494424

RESUMO

Fluorescent initiator tRNAs (tRNAi) play a crucial role in studying protein synthesis, yet generating highly fluorescent tRNAi complexes remains challenging. We present an optimized strategy to effectively generate highly fluorescent initiator-tRNA complexes in living cells. Our strategy allows the generation of Fluo-Met-tRNAiMet complexes. These complexes can have highly chromogenic N-terminal labeling. For generating such complexes, we use either purified fluorescent methionine (PFM) or non-purified fluorescently labeled methionine (NPFM). Furthermore, PFM promotes the active generation of endogenous tRNAi in cells, leading to highly efficient Fluo-Met-tRNAiMet complexes. Finally, PFM-tRNAiMet complexes also facilitate the visualization of native fluorescently labeled Tat binding to beads. This demonstrates the potential of our approach to advance precision protein engineering and biotechnology applications.


Assuntos
Biossíntese de Proteínas , RNA de Transferência de Metionina , RNA de Transferência de Metionina/química , RNA de Transferência de Metionina/genética , RNA de Transferência de Metionina/metabolismo , Metionina/genética , Metionina/metabolismo , Corantes , Racemetionina/metabolismo
13.
J Agric Food Chem ; 72(12): 6414-6423, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38501560

RESUMO

Previous research has demonstrated that in pregnant mice deficient in l-methionine (Met), the mixture of the dipeptide l-methionyl-l-methionine (Met-Met) with Met was more effective than Met alone in promoting mammogenesis and lactogenesis. This study aimed to investigate the role of a novel long noncoding RNA (lncRNA), named mammary gland proliferation-associated lncRNA (MGPNCR), in these processes. Transcriptomic analysis of mammary tissues from Met-deficient mice, supplemented either with a Met-Met/Met mixture or with Met alone, revealed significantly higher MGPNCR expression in the Met group compared to the mixture group, a finding recapitulated in a mammary epithelial cell model. Our findings suggested that MGPNCR hindered mammogenesis and milk protein synthesis by binding to eukaryotic initiation factor 4B (eIF4B). This interaction promoted the dephosphorylation of eIF4B at serine-422 by enhancing its association with protein phosphatase 2A (PP2A). Our study sheds light on the regulatory mechanisms of lncRNA-mediated dipeptide effects on mammary cell proliferation and milk protein synthesis. These insights underscore the potential benefits of utilizing dipeptides to improve milk protein in animals and potentially in humans.


Assuntos
Fatores de Iniciação em Eucariotos , Metionina , RNA Longo não Codificante , Gravidez , Humanos , Feminino , Animais , Camundongos , Metionina/metabolismo , RNA Longo não Codificante/metabolismo , Dipeptídeos/metabolismo , Racemetionina/metabolismo , Proteínas do Leite/metabolismo , Células Epiteliais/metabolismo , Glândulas Mamárias Animais/metabolismo
14.
Sci Rep ; 14(1): 6915, 2024 03 22.
Artigo em Inglês | MEDLINE | ID: mdl-38519576

RESUMO

Neuronal aging may be, in part, related to a change in DNA methylation. Thus, methyl donors, like folate and methionine, may play a role in cognitive changes associated to neuronal aging. To test the role of these metabolites, we performed stereotaxic microinjection of these molecules into the dentate gyrus (DG) of aged mice (an average age of 21 month). Folate, but not S-Adenosyl-Methionine (SAM), enhances cognition in aged mice. In the presence of folate, we observed partial rejuvenation of DG cells, characterized by the expression of juvenile genes or reorganization of extracellular matrix. Here, we have also tried to identify the mechanism independent of DNA methylation, that involve folate effects on cognition. Our analyses indicated that folate binds to folate receptor α (FRα) and, upon folate binding, FRα is transported to cell nucleus, where it is acting as transcription factor for expressing genes like SOX2 or GluN2B. In this work, we report that a FRα binding peptide also replicates the folate effect on cognition, in aged mice. Our data suggest that such effect is not sex-dependent. Thus, we propose the use of this peptide to improve cognition since it lacks of folate-mediated side effects. The use of synthetic FRα binding peptides emerge as a future strategy for the study of brain rejuvenation.


Assuntos
Receptor 1 de Folato , Rejuvenescimento , Animais , Camundongos , Cognição , Giro Denteado/metabolismo , Receptor 1 de Folato/metabolismo , Ácido Fólico/metabolismo , Metionina , Peptídeos/metabolismo , S-Adenosilmetionina
15.
Microb Biotechnol ; 17(3): e14433, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38528766

RESUMO

l-Methionine (l-Met) has gained remarkable interest due to its multifaceted and versatile applications in the fields of nutrition, pharmaceuticals and clinical practice. In this study, the fluxes of the challenging l-Met biosynthesis in the producer strain Escherichia coli (E. coli) DM2853 were fine-tuned to enable improved l-Met production. The potential bottlenecks identified in sulfur assimilation and l-Met synthesis downstream of O-succinyl-l-homoserine (OSHS) were addressed by overexpressing glutaredoxin 1 (grxA), thiosulfate sulfurtransferase (pspE) and O-succinylhomoserine lyase (metB). Although deemed as a straightforward target for improving glucose-to-Met conversion, the yields remained at approximately 12%-13% (g/g). Instead, intracellular l-Met pools increased by up to four-fold with accelerated kinetics. Overexpression of the Met exporter ygaZH may serve as a proper valve for releasing the rising internal Met pressure. Interestingly, the export kinetics revealed maximum saturated export rates already at low growth rates. This scenario is particularly advantageous for large-scale fermentation when product formation is ideally uncoupled from biomass formation to achieve maximum performance within the technical limits of large-scale bioreactors.


Assuntos
Proteínas de Escherichia coli , Escherichia coli , Escherichia coli/genética , Escherichia coli/metabolismo , Metionina/metabolismo , Racemetionina , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Fermentação
16.
Biomolecules ; 14(3)2024 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-38540746

RESUMO

Amino acid restriction induces cellular stress and cells often respond via the induction of autophagy. Autophagy or 'self-eating' enables the recycling of proteins and provides the essential amino acids needed for cell survival. Of the naturally occurring amino acids, methionine restriction has pleiotropic effects on cells because methionine also contributes to the intracellular methyl pools required for epigenetic controls as well as polyamine biosynthesis. In this report, we describe the chemical synthesis of four diastereomers of a methionine depletion agent and demonstrate how controlled methionine efflux from cells significantly reduces intracellular methionine, S-adenosylmethionine (SAM), S-adenosyl homocysteine (SAH), and polyamine levels. We also demonstrate that human pancreatic cancer cells respond via a lipid signaling pathway to induce autophagy. The methionine depletion agent causes the large amino acid transporter 1 (LAT1) to preferentially work in reverse and export the cell's methionine (and leucine) stores. The four diastereomers of the lead methionine/leucine depletion agent were synthesized and evaluated for their ability to (a) efflux 3H-leucine from cells, (b) dock to LAT1 in silico, (c) modulate intracellular SAM, SAH, and phosphatidylethanolamine (PE) pools, and (d) induce the formation of the autophagy-associated LC3-II marker. The ability to modulate the intracellular concentration of methionine regardless of exogenous methionine supply provides new molecular tools to better understand cancer response pathways. This information can then be used to design improved therapeutics that target downstream methionine-dependent processes like polyamines.


Assuntos
Aminoácidos , Metionina , Humanos , Leucina/metabolismo , Metionina/metabolismo , S-Adenosilmetionina/metabolismo , Poliaminas/metabolismo , Racemetionina
17.
Int J Mol Sci ; 25(6)2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38542431

RESUMO

One-carbon folate metabolites and one-carbon-related amino acids play an important role in human physiology, and their detection in biological samples is essential. However, poor stability as well as low concentrations and occurrence in different species in various biological samples make their quantification very challenging. The aim of this study was to develop a simple, fast, and sensitive ultra-high-performance liquid chromatography MS/MS (UHPLC-MS/MS) method for the simultaneous quantification of various one-carbon folate metabolites (folic acid (FA), tetrahydrofolic acid (THF), p-aminobenzoyl-L-glutamic acid (pABG), 5-formyltetrahydrofolic acid (5-CHOTHF), 5-methyltetrahydrofolic acid (5-CH3THF), 10-formylfolic acid (10-CHOFA), 5,10-methenyl-5,6,7,8-tetrahydrofolic acid (5,10-CH+-THF), and 4-α-hydroxy-5-methyltetrahydrofolate (hmTHF)) and one-carbon-related amino acids (homocysteine (Hcy), methionine (Met), S-ade-L-homocysteine (SAH), and S-ade-L-methionine (SAM)). The method was standardized and validated by determining the selectivity, carryover, limits of detection, limits of quantitation, linearity, precision, accuracy, recovery, and matrix effects. The extraction methods were optimized with respect to several factors: protease-amylase treatment on embryos, deconjugation time, methanol precipitation, and proteins' isoelectric point precipitation on the folate recovery. Ten one-carbon folate metabolites and four one-carbon-related amino acids were detected using the UHPLC-MS/MS technique in various biological samples. The measured values of folate in human plasma, serum, and whole blood (WB) lay within the concentration range for normal donors. The contents of each analyte in mouse plasma were as follows: pABG (864.0 nmol/L), 5-CH3THF (202.2 nmol/L), hmTHF (122.2 nmol/L), Met (8.63 µmol/L), and SAH (0.06 µmol/L). The concentration of each analyte in mouse embryos were as follows: SAM (1.09 µg/g), SAH (0.13 µg/g), Met (16.5 µg/g), 5,10-CH+THF (74.3 ng/g), pABG (20.6 ng/g), and 5-CH3THF (185.4 ng/g). A simple and rapid sample preparation and UHPLC-MS/MS method was developed and validated for the simultaneous determination of the one-carbon-related folate metabolites and one-carbon-related amino acids in different biological samples.


Assuntos
Carbono , Espectrometria de Massas em Tandem , Humanos , Camundongos , Animais , Cromatografia Líquida de Alta Pressão/métodos , Espectrometria de Massas em Tandem/métodos , Ácido Fólico/metabolismo , Metionina , Racemetionina , Ácido Glutâmico , Homocisteína
18.
Nutrients ; 16(6)2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38542805

RESUMO

Caffeine (1,3,7-trimethylxanthine) is a widely consumed bioactive substance worldwide. Our recent study showed that a reduction in both reproduction and yolk protein production (vitellogenesis) caused by caffeine intake were improved by vitamin B12 supplementation, which is an essential co-factor in methionine metabolism. In the current study, we investigated the role of methionine in the reproduction of caffeine-ingested animals (CIAs). We assessed the effect of methionine metabolism on CIAs and found that caffeine intake decreased both methionine levels and essential enzymes related to the methionine cycle. Furthermore, we found that the caffeine-induced impairment of methionine metabolism decreased vitellogenesis and increased germ cell apoptosis in an LIN-35/RB-dependent manner. Interestingly, the increased germ cell apoptosis was restored to normal levels by methionine supplementation in CIAs. These results indicate that methionine supplementation plays a beneficial role in germ cell health and offspring development by regulating vitellogenesis.


Assuntos
Caenorhabditis elegans , Metionina , Animais , Metionina/farmacologia , Metionina/metabolismo , Cafeína/farmacologia , Cafeína/metabolismo , Apoptose , Células Germinativas , Racemetionina/metabolismo , Suplementos Nutricionais
19.
Biomed Res ; 45(2): 67-76, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38556264

RESUMO

We previously reported that tenascin-X (Tnxb) aggravates hepatic fibrosis in mice fed a high-fat and high-cholesterol diet with high levels of phosphorus and calcium (HFCD). In this study, we investigated Tnxb expression in livers with fibrosis caused by administration of a methionine-chorine-deficient (MCD) diet in mice. Whole transcriptome analysis showed that Tnxb was one of the genes with increased expression in livers of MCD diet-fed mice compared with that in livers of normal diet (ND)-fed mice. In microarray and subsequent microRNA (miRNA) network analyses, miR-378a-5p and miR-486-5p were identified in livers of MCD diet-fed mice as downregulated miRNAs, which have their predicted target sites in the 3' untranslated region of Tnxb mRNA and might suppress the translation of Tnxb mRNA. RT-qPCR analyses of livers of MCD diet-fed mice compared with livers of ND-fed mice verified the upregulation of Tnxb and fibrosis-triggering genes and conversely the downregulation of miR-378a-5p and miR-486-5p. Overexpression of miR-378a-5p and miR-486-5p resulted in decreased level not only of the FLAG-tagged fibrinogen-like domain of Tnxb protein (FLAG-mTNX-FG) but also of endogenous Tnxb protein in murine cultured cells. These results indicate that expression of Tnxb is regulated by miR-378a-5p and miR-486-5p in hepatic fibrosis following MCD diet feeding.


Assuntos
Metionina , MicroRNAs , Tenascina , Camundongos , Animais , Colina , Cirrose Hepática/genética , MicroRNAs/genética , Dieta/efeitos adversos , Fibrose , Racemetionina , RNA Mensageiro , Camundongos Endogâmicos C57BL
20.
PLoS One ; 19(3): e0301133, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38547097

RESUMO

PURPOSE: Nonalcoholic steatohepatitis (NASH) is the progressive form of nonalcoholic fatty liver disease (NAFLD), which has a high risk of cirrhosis, liver failure, and hepatocellular carcinoma. Piperine (Pip) is an extract of plants with powerful anti-inflammatory effects, however, the function of Pip in NASH remains elusive. Here, we aim to explore the role of Pip in NASH and to find the possible mechanisms. METHODS: Methionine and choline-deficient (MCD) diets were used to induce steatohepatitis, methionine- and choline-sufficient (MCS) diets were used as the control. After Pip treatment, H&E staining, Oil Red O staining, hepatic triglyceride (TG) content and F4/80 expression were performed to analysis liver steatosis and inflammation; Masson's staining, COL1A1 and α-SMA were detected liver fibrosis. Lipopolysaccharide (LPS) -treated AML12 cells were used to as the cell model to induce pyroptosis. Then, pyroptosis-related proteins, IL-1ß and LDH release were detected in vivo and in vitro. Finally, NF-κB inhibitor, BAY11-7082, was used to further demonstrate the mechanism of Pip in NASH. RESULTS: The study found that Pip alleviated liver steatosis, inflammation, hepatocyte injury, and fibrosis in mice fed with MCD diets. Moreover, the pyroptosis markers (NLRP3, ASC, caspase-1 p20, and GSDMD), IL-1ß and LDH release were decreased by Pip treatment. NF-κB activation was suppressed by Pip treatment and pyroptosis-related proteins were down regulated by BAY11-7082. CONCLUSION: Pip ameliorates NASH progression, and the therapeutical effect was associated with inhibition of hepatocyte pyroptosis induced by NF-κB.


Assuntos
Alcaloides , Benzodioxóis , Nitrilas , Hepatopatia Gordurosa não Alcoólica , Piperidinas , Alcamidas Poli-Insaturadas , Sulfonas , Camundongos , Animais , Hepatopatia Gordurosa não Alcoólica/patologia , NF-kappa B/metabolismo , Piroptose , Fígado/metabolismo , Cirrose Hepática/patologia , Fibrose , Inflamação/patologia , Colina/metabolismo , Hepatócitos/metabolismo , Metionina/metabolismo , Camundongos Endogâmicos C57BL
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...