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1.
Bioorg Chem ; 128: 106095, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36049321

RESUMO

Ribosome assisted protein synthesis in all prokaryotes begins with a formylated methionine. Deformylation and demethionylation of these newly synthesized proteins are critical co-translational events carried out by peptide deformylase (PDF) and methionine aminopeptidase (MetAP) in all living cells. Since the mechanism of N-terminal modification is common between the infectious microbes and the host human cells, it is a challenge to identify selective inhibitors. Given that both MetAP and PDF are metalloenzymes, and have strong affinity for hydroxamic acids, we reasoned that the azaindole-based hydroxamic acids could inhibit the PDF enzymes. In the present study we describe the screening of a 17-compound library with 4- and 5- substituted azaindole hydroxamic acid derivatives against PDF enzyme from H. influenzae (HiPDF), M. tuberculosis (MtPDF) and human PDF (HsPDF). Several of these molecules showed nanomolar inhibition against HiPDF enzyme, best at 21 nM (15). On the other hand, none of these compounds inhibited the human enzyme while only two molecules showed moderate inhibition against Mtb enzyme. Surprisingly only 5-substituted azaindole derivatives inhibited the PDF enzymes. Some of the 5-substituted azaindole compounds inhibited the growth of different microbes indicating their potential application in antimicrobial therapy. Crystallographic and modeling studies provided the mechanistic view of regioselective inhibition.


Assuntos
Haemophilus influenzae , Ácidos Hidroxâmicos , Amidoidrolases , Antibacterianos/farmacologia , Compostos Aza , Inibidores Enzimáticos/química , Escherichia coli , Haemophilus influenzae/metabolismo , Humanos , Ácidos Hidroxâmicos/química , Indóis , Metionina/metabolismo
2.
Cell Metab ; 34(9): 1280-1297.e9, 2022 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-36070681

RESUMO

Epstein-Barr virus (EBV) subverts host epigenetic pathways to switch between viral latency programs, colonize the B cell compartment, and reactivate. Within memory B cells, the reservoir for lifelong infection, EBV genomic DNA and histone methylation marks restrict gene expression. But this epigenetic strategy also enables EBV-infected tumors, including Burkitt lymphomas, to evade immune detection. Little is known about host cell metabolic pathways that support EBV epigenome landscapes. We therefore used amino acid restriction, metabolomic, and CRISPR approaches to identify that an abundant methionine supply and interconnecting methionine and folate cycles maintain Burkitt EBV gene silencing. Methionine restriction, or methionine cycle perturbation, hypomethylated EBV genomes and de-repressed latent membrane protein and lytic gene expression. Methionine metabolism also shaped EBV latency gene regulation required for B cell immortalization. Dietary methionine restriction altered murine Burkitt xenograft metabolomes and de-repressed EBV immunogens in vivo. These results highlight epigenetic/immunometabolism crosstalk supporting the EBV B cell life cycle and suggest therapeutic approaches.


Assuntos
Infecções por Vírus Epstein-Barr , Herpesvirus Humano 4 , Animais , Epigênese Genética , Epigenoma , Infecções por Vírus Epstein-Barr/metabolismo , Herpesvirus Humano 4/genética , Herpesvirus Humano 4/metabolismo , Humanos , Metionina/metabolismo , Camundongos , Latência Viral/genética
3.
Int J Mol Sci ; 23(17)2022 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-36077461

RESUMO

The progression of nonalcoholic fatty liver disease (NAFLD) is associated with alterations of the gut-liver axis. The activation of toll-like receptor 4 (TLR4) pathways by endotoxins, such as lipopolysaccharide (LPS), contributes to liver injury. The aim of the present study was to evaluate the possible beneficial effects of a calcium-sulphate-bicarbonate natural mineral water on the gut-liver axis by evaluating liver and terminal ileum histopathology in a murine model of NAFLD. NAFLD was induced in mice by administrating a methionine-choline-deficient (MCD) diet. The following experimental groups were evaluated: controls (N = 10); MCD+Tap water (MCD; N = 10); MCD+Calcium-sulphate-bicarbonate water (MCD/Wcsb; N = 10). Mice were euthanised after 4 and 8 weeks. Liver and terminal ileum samples were collected. Samples were studied by histomorphology, immunohistochemistry, and immunofluorescence. In mice subjected to the MCD diet, treatment with mineral water improved inflammation and fibrosis, and was associated with a reduced number of activated hepatic stellate cells when compared to MCD mice not treated with mineral water. Moreover, MCD/Wcsb mice showed lower liver LPS localization and less activation of TLR4 pathways compared to the MCD. Finally, Wcsb treatment was associated with improved histopathology and higher occludin positivity in intestinal mucosa. In conclusion, calcium-sulphate-bicarbonate water may exert modulatory activity on the gut-liver axis in MCD mice, suggesting potential beneficial effects on NAFLD.


Assuntos
Deficiência de Colina , Águas Minerais , Hepatopatia Gordurosa não Alcoólica , Animais , Bicarbonatos/metabolismo , Cálcio/metabolismo , Sulfato de Cálcio , Colina/metabolismo , Deficiência de Colina/complicações , Deficiência de Colina/metabolismo , Modelos Animais de Doenças , Lipopolissacarídeos/metabolismo , Fígado/metabolismo , Metionina/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Hepatopatia Gordurosa não Alcoólica/metabolismo , Sulfatos/metabolismo , Receptor 4 Toll-Like/metabolismo
4.
Int J Mol Sci ; 23(16)2022 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-36012485

RESUMO

All forms of restriction, from caloric to amino acid to glucose restriction, have been established in recent years as therapeutic options for various diseases, including cancer. However, usually there is no direct comparison between the different restriction forms. Additionally, many cell culture experiments take place under static conditions. In this work, we used a closed perfusion culture in murine L929 cells over a period of 7 days to compare methionine restriction (MetR) and glucose restriction (LowCarb) in the same system and analysed the metabolome by liquid chromatography mass spectrometry (LC-MS). In addition, we analysed the inhibition of glycolysis by 2-deoxy-D-glucose (2-DG) over a period of 72 h. 2-DG induced very fast a low-energy situation by a reduced glycolysis metabolite flow rate resulting in pyruvate, lactate, and ATP depletion. Under perfusion culture, both MetR and LowCarb were established on the metabolic level. Interestingly, over the period of 7 days, the metabolome of MetR and LowCarb showed more similarities than differences. This leads to the conclusion that the conditioned medium, in addition to the different restriction forms, substantially reprogramm the cells on the metabolic level.


Assuntos
Desoxiglucose , Glucose , Animais , Desoxiglucose/farmacologia , Glucose/metabolismo , Glicólise , Espectrometria de Massas , Metionina/metabolismo , Camundongos , Perfusão
5.
Int J Mol Sci ; 23(16)2022 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-36012717

RESUMO

The sesquiterpenoid hormone methyl farnesoate (MF) plays a vital role during crustacean development, which is mainly evidenced by its varied titers during different developmental stages. However, the biosynthesis pathways of MF remain obscure to some extent. In this study, we identified the complete MF biosynthesis and related pathway genes in Scylla paramamosain, including three involved in acetyl-CoA metabolism, eight in the mevalonate pathway, five in the sesquiterpenoids synthesis pathway, and five in the methionine cycle pathway. Bioinformatics, genomic structure, and phylogenetic analysis indicated that the JH biosynthesis genes might have experienced evolution after species differentiation. The mRNA tissue distribution analysis revealed that almost all genes involving in or relating to MF syntheses were highly expressed in the mandibular organ (MO), among which juvenile hormone acid methyltransferase was exclusively expressed in the MO, suggesting that most of these genes might mainly function in MF biosynthesis and that the methionine cycle pathway genes might play a crucial regulatory role during MF synthesis. In addition, the phylogenetic and tissue distribution analysis of the cytochrome P450 CYP15-like gene suggested that the epoxidized JHs might exist in crustaceans, but are mainly synthesized in hepatopancreas rather than the MO. Finally, we also found that betaine-homocysteine S-methyltransferase genes were lost in insects while methionine synthase was probably lost in most insects except Folsomia candida, indicating a regulatory discrepancy in the methionine cycle between crustaceans and insects. This study might increase our understanding of synthetic metabolism tailored for sesquiterpenoid hormones in S. paramamosain and other closely related species.


Assuntos
Braquiúros , Ácidos Graxos Insaturados , Animais , Braquiúros/genética , Braquiúros/metabolismo , Ácidos Graxos Insaturados/biossíntese , Metionina/metabolismo , Filogenia
6.
Zhonghua Gan Zang Bing Za Zhi ; 30(6): 649-655, 2022 Jun 20.
Artigo em Chinês | MEDLINE | ID: mdl-36038328

RESUMO

Objective: To analyze and compare the differentially expressed genes (DEGs) of Yes-associated protein (YAP)-positive and negative hepatocytes and further understand the preliminary functional characteristics of YAP-positive hepatocytes in an early mouse model of nonalcoholic steatohepatitis (NASH) with transcriptome sequence (RNA-Seq). Methods: C57BL/6 mice were fed with methionine-choline deficiency (MCD) diet for 2 weeks to establish an early NASH model, and the control group was fed with normal diet. Liver tissue was stained with hematoxylin-eosin (HE) and Sirius red, and the pathological score was recorded. The expression of YAP and P-YAP were determined by immunohistochemistry (IHC) in liver tissues. Primary hepatocytes with viability greater than 90% were isolated and purified by collagenase perfusion combined with Percoll density gradient centrifugation. YAP-positive and negative hepatocytes were assessed by YAP antibody, flow cytometry and RNA-Seq analyses. Sequencing results were screened by GO, KEGG and interaction network analysis methods. RT-PCR was used to verify the expression levels of YAP and some DEGs in liver tissue model group. Two samples mean was compared by independent samples t-test. Results: Compared with the control group, the HE-stained liver tissue of MCD-induced mice at 2 weeks showed steatosis (pathological score 1.07±0.21), accompanied by lobular inflammation (pathological score 1.13±0.32) and ballooned hepatocyte (pathological score 0.80) ±0.20). Sirius red staining showed non-significant liver fibrosis (pathological score 0.40±0.40). IHC showed partial YAP-positive hepatocytes expression in an early stage of NASH. RNA-Seq analysis showed that clean reads of YAP-positive and negative hepatocytes were 49 310 604 and 5 4820 036, respectively. Compared with YAP-negative hepatocytes, YAP-positive hepatocytes had differential expression of 5 565 genes, including 1 662 up-regulated genes and 3 903 down-regulated genes. GO analysis of up-regulated genes showed that the metabolic processes related to mitochondrial functions, such as purine nucleoside triphosphate and nucleoside triphosphate were significantly enriched in biological processes (BP), while down-regulated gene analysis showed that olfactory-related receptor were significantly enriched in BP. KEGG analysis showed that DEGs were enriched in 292 pathways, and oxidative phosphorylation (OXPHOS) pathway was significantly enriched in signaling pathway. RT-PCR validated that inflammatory factors (interleukin-1ß, interleukin-6), YAP and its target genes (Cyr61, Ankrd1), and Cox5b and Sdhc genes were significantly up-regulated in the OXPHOS pathway, which was consistent with the sequencing results. In addition, eight key genes with interaction network analysis were predicted. Conclusion: Changes in hepatocyte metabolic levels may be associated with increased YAP activity in an early stage of NASH.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Animais , Modelos Animais de Doenças , Hepatócitos/metabolismo , Fígado/patologia , Metionina/genética , Metionina/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Hepatopatia Gordurosa não Alcoólica/patologia , Análise de Sequência , Transcriptoma
7.
Ann Med ; 54(1): 2233-2245, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-35950602

RESUMO

BACKGROUND: Immune responses are important in the progression of non-alcoholic fatty liver disease (NAFLD). Natural killer T (NKT) cells are main components of the innate immune system that modulate immunity. However, the role of NKT cells in NAFLD remains controversial. OBJECTIVE: We aimed to investigate the role of NKT cells in non-alcoholic steatohepatitis (NASH)-related fibrosis in fast food diet (FFD)- and methionine choline-deficient (MCD) diet-induced mouse models. METHODS: Hepatic NKT cells were analysed in wild-type (WT) and CD1d-/- mice fed FFD or MCD diets. Hepatic pathology, cytokine profiles and liver fibrosis were evaluated. Furthermore, the effect of chronic administration of α-galactosylceramide (α-GalCer) on liver fibrosis was investigated in both FFD- and MCD-treated mice. RESULTS: FFD induced a significant depletion of hepatic NKT cells, thus leading to mild to moderate NASH and early-stage fibrosis, while mice fed MCD diets developed severe liver inflammation and progressive fibrosis without a significant change in hepatic NKT cell abundance. FFD induced a similar liver fibrogenic response in CD1d-/- and WT mice, while MCD induced a higher hepatic mRNA expression of Col1α1 and TIMP1 as well as relative fibrosis density in CD1d-/- mice than WT mice (31.8 vs. 16.3, p = .039; 40.0 vs. 22.6, p = .019; 2.24 vs. 1.59, p = .036). Chronic administration of α-GalCer induced a higher hepatic mRNA expression of TIMP1 in MCD-treated mice than controls (36.7 vs. 14.9, p = .005). CONCLUSION: NKT cells have protective roles in NAFLD as the disease progresses. During diet-induced steatosis, mild to moderate NASH and the early stage of fibrosis, hepatic NKT cells are relatively depleted, leading to a proinflammatory status. In severe NASH and the advanced stage of liver fibrosis, NKT cells play a role in inhibiting the NASH-related fibrogenic response. Chronic administration of α-GalCer induces NKT cell anergy and tolerance, which may play a role in promoting the liver fibrogenic response.


Assuntos
Células T Matadoras Naturais , Hepatopatia Gordurosa não Alcoólica , Animais , Dieta , Fibrose , Humanos , Fígado/metabolismo , Cirrose Hepática/etiologia , Cirrose Hepática/patologia , Metionina/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Células T Matadoras Naturais/metabolismo , Células T Matadoras Naturais/patologia , Hepatopatia Gordurosa não Alcoólica/metabolismo , RNA Mensageiro/metabolismo
8.
Cell Rep ; 40(9): 111290, 2022 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-36044860

RESUMO

Adaptive stress resistance in microbes is mostly attributed to the expression of stress response genes, including heat-shock proteins. Here, we report a response of E. coli to heat stress caused by degradation of an enzyme in the methionine biosynthesis pathway (MetA). While MetA degradation can inhibit growth, which by itself is detrimental for fitness, we show that it directly benefits survival at temperatures exceeding 50°C, increasing survival chances by more than 1,000-fold. Using both experiments and mathematical modeling, we show quantitatively how protein expression, degradation rates, and environmental stressors cause long-term growth inhibition in otherwise habitable conditions. Because growth inhibition can be abolished with simple mutations, namely point mutations of MetA and protease knockouts, we interpret the breakdown of methionine synthesis as a system that has evolved to halt growth at high temperatures, analogous to "thermal fuses" in engineering that shut off electricity to prevent overheating.


Assuntos
Proteínas de Escherichia coli , Escherichia coli , Resposta ao Choque Térmico , Homoserina O-Succiniltransferase , Escherichia coli/genética , Escherichia coli/fisiologia , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Proteínas de Choque Térmico/genética , Proteínas de Choque Térmico/metabolismo , Resposta ao Choque Térmico/genética , Resposta ao Choque Térmico/fisiologia , Temperatura Alta , Metionina/metabolismo , Temperatura
9.
J Dairy Sci ; 105(9): 7787-7804, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35879168

RESUMO

We investigated effects of rumen-protected Met (RPM) during a heat stress (HS) challenge on (1) hepatic abundance of mTOR, insulin, and antioxidant signaling proteins, (2) enzymes in 1-carbon metabolism, and (3) innate immunity. Holstein cows (n = 32; mean ± standard deviation, 184 ± 59 d in milk) were randomly assigned to 1 of 2 environmental groups, and 1 of 2 diets [total mixed ration (TMR) with RPM (Smartamine M; 0.105% dry matter as top-dress) or TMR without (CON); n = 16/diet] in a split-plot crossover design. There were 2 periods with 2 phases. During phase 1 (9 d), all cows were in thermoneutral conditions (TN; temperature-humidity index = 60 ± 3) and fed ad libitum. During phase 2 (9 d), half the cows (n = 8/diet) were exposed to HS using electric heat blankets. The other half (n = 8/diet) remained in TN, but was pair-fed to HS counterparts. After a 14-d washout and 7-d adaptation period, the study was repeated (period 2) and environmental treatments were inverted relative to phase 2, but dietary treatments were the same. Blood was collected on d 6 of each phase 2 to measure immune function and isolate whole-blood RNA. Liver biopsies were performed at the end of each period for cystathione ß-synthase (CBS) and methionine adenosyltransferase activity, glutathione concentration, and protein abundance. Data were analyzed using PROC MIXED in SAS. Abundance of CUL3, inhibitor of antioxidant responses, tended to be downregulated by HS suggesting increased oxidative stress. Heat-shock protein 70 abundance was upregulated by HS. Phosphorylated mTOR abundance was greater overall with RPM, suggesting an increase in pathway activity. An environment × diet (E × D) effect was observed for protein kinase B (AKT), whereas there was a tendency for an interaction for phosphorylated AKT. Abundance of AKT was upregulated in CON cows during HS versus TN, this was not observed in RPM cows. For phosphorylated AKT, tissue from HS cows fed CON had greater abundance compared with all other treatments. The same effect was observed for EIF2A (translation initiation) and SLC2A4 (insulin-induced glucose uptake). An E × D effect was observed for INSR due to upregulation in CON cows during HS versus TN cows fed CON or RPM. There was an E × D effect for CBS, with lower activity in RPM versus CON cows during HS. The CON cows tended to have greater CBS during HS versus TN. An E × D effect was observed for methionine adenosyltransferase, with lower activity in RPM versus CON during HS. Although activity increased in CON during HS versus TN, RPM cows tended to have greater activity during TN. Neutrophil and monocyte oxidative burst and monocyte phagocytosis decreased with HS. An (E × D) effect was observed for whole-blood mRNA abundance of CBS, SOD1 and CSAD; RPM led to upregulation during TN versus HS. Regardless of diet, CDO1, CTH, and SOD1 decreased with HS. Although HS increased hepatic HSP70 and seemed to alter antioxidant signaling, feeding RPM may help cows maintain homeostasis in mTOR, insulin signaling, and 1-carbon metabolism. Feeding RPM also may help maintain whole-blood antioxidant response during HS, which is an important aspect of innate immune function.


Assuntos
Doenças dos Bovinos , Transtornos de Estresse por Calor , Animais , Antioxidantes/metabolismo , Carbono/metabolismo , Bovinos , Doenças dos Bovinos/metabolismo , Dieta/veterinária , Suplementos Nutricionais , Feminino , Transtornos de Estresse por Calor/metabolismo , Transtornos de Estresse por Calor/veterinária , Resposta ao Choque Térmico , Insulina/metabolismo , Lactação/fisiologia , Fígado/metabolismo , Metionina/metabolismo , Metionina Adenosiltransferase , Leite/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Rúmen/metabolismo , Superóxido Dismutase-1 , Serina-Treonina Quinases TOR/metabolismo
10.
mBio ; 13(4): e0075422, 2022 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-35856606

RESUMO

Biodesulfurization is a process that selectively removes sulfur from dibenzothiophene and its derivatives. Several natural biocatalysts harboring the highly conserved desulfurization operon dszABC, which is significantly repressed by methionine, cysteine, and inorganic sulfate, have been isolated. However, the available information on the metabolic regulation of gene expression is still limited. In this study, scarless knockouts of the reverse transsulfuration pathway enzyme genes cbs and metB were constructed in the desulfurizing strain Rhodococcus sp. strain IGTS8. We provide sequence analyses and report the enzymes' involvement in the sulfate- and methionine-dependent repression of biodesulfurization activity. Sulfate addition in the bacterial culture did not repress the desulfurization activity of the Δcbs strain, whereas deletion of metB promoted a significant biodesulfurization activity for sulfate-based growth and an even higher desulfurization activity for methionine-grown cells. In contrast, growth on cysteine completely repressed the desulfurization activity of all strains. Transcript level comparison uncovered a positive effect of cbs and metB gene deletions on dsz gene expression in the presence of sulfate and methionine, but not cysteine, offering insights into a critical role of cystathionine ß-synthase (CßS) and MetB in desulfurization activity regulation. IMPORTANCE Precise genome editing of the model biocatalyst Rhodococcus qingshengii IGTS8 was performed for the first time, more than 3 decades after its initial discovery. We thus gained insight into the regulation of dsz gene expression and biocatalyst activity, depending on the presence of two reverse transsulfuration enzymes, CßS and MetB. Moreover, we observed an enhancement of biodesulfurization capability in the presence of otherwise repressive sulfur sources, such as sulfate and l-methionine. The interconnection of cellular sulfur assimilation strategies was revealed and validated.


Assuntos
Rhodococcus , Cisteína/metabolismo , Metionina/metabolismo , Rhodococcus/genética , Rhodococcus/metabolismo , Sulfatos/metabolismo , Enxofre/metabolismo
11.
FASEB J ; 36(8): e22464, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35881391

RESUMO

In the present experiment, we study the function of methionine on hair follicle development in heat-stressed Rex Rabbits and its potential molecular mechanism. Rex rabbits were randomly divided into 5 groups (30 replicates per group): control group (20-25°C, fed basic diet), heat stress group (30-34°C, fed basic diet), heat stress + methionine group (30-34°C, fed 0.15% methionine in addition to the basic diet). fed basic diet (control), heat stress + methionine group (30-34°C, fed 0.3% methionine in addition to the basic diet), heat stress + methionine group (30-34°C, fed 0.45% methionine in addition to the basic diet). The results show that heat stress decreases the hair follicle density of Rex rabbits, and the diet methionine addition significantly increases the hair follicle density of heat-stressed Rabbits (p < .05). Heat stress increased serum HSP70 concentration and skin HSP70 gene expression, 0.15%-0.3% methionine but not 0.45% addition alleviated the effect of heat stress. Dietary 0.15% methionine addition significantly increases the gene expression of Wnt10b, ß-catenin, LEF, FZD4, LRP6, Shh, HGF, EGF, and Noggin in heat-stressed Rex rabbits and observably decreases the gene expression of BMP2/4 and TGFb. There was no significant effect of methionine on the expression of IGF1 and FGF5/7 gene expression. In conclusion, methionine maybe promotes hair follicle development via TGFß-BMP/Shh-Noggin, Wnt10b/ß-catenin, EGF, and HGF signaling pathways in heat-stressed rabbits.


Assuntos
Metionina , beta Catenina , Animais , Suplementos Nutricionais , Fator de Crescimento Epidérmico/metabolismo , Folículo Piloso/metabolismo , Resposta ao Choque Térmico , Metionina/metabolismo , Preconceito , Coelhos , beta Catenina/metabolismo
12.
Phytomedicine ; 104: 154326, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35853303

RESUMO

BACKGROUND: Non-alcoholic fatty liver disease (NAFLD) especially the later stage non-alcoholic steatohepatitis (NASH) seriously endangers human's health and has become a global public health issue in recent years. Mailuoning Oral Liquid (MLN) is a modern traditional Chinese medicine prescription composed by Lonicerae japonicae flos, Achyranthis bidentatae radix, Scrophulariae radix and Dendrobium Caulis. MLN is generally used to treat the syndrome of blood stasis in clinical practice. PURPOSE: To observe the alleviation of MLN on NASH in vivo, and explore the possible underlying mechanism. Furthermore, this study also aims to find which Chinese medicinal drug contained in MLN exerts the main pharmacological activity. METHODS: NASH model was induced in mice by feeding with methionine and choline deficient (MCD) diet. The effects of MLN on hepatic lipids accumulation, liver inflammation, hepatic fibrosis, and the expression of some molecules were investigated by histological observation, biochemical index analysis, quantitative real-time PCR and western blot. Network pharmacology was applied to predict those involved molecular targets and potential mechanisms, which was further validated in vivo. BODIPY fluorescence staining assay was used to detect cellular lipids accumulation. RESULTS: MLN (7.8, 23.4 ml/kg) improved NASH in MCD-fed mice. Network pharmacology results demonstrated that peroxisome proliferator-activated receptor α (PPARα) signaling pathway was crucially involved in the MLN-provided alleviation on NASH. Further experimental validation results showed that MLN increased the expression of peroxisome proliferator-activated receptor gamma coactivator-1α (PGC-1α) and restored the decreased expression of nuclear PPARα in MCD-fed mice. Further results displayed that Achyranthis bidentatae radix and Lonicerae japonicae flos contributed greatly to the MLN-provided alleviation on NASH in vivo. BODIPY fluorescence staining assay showed that 25R-inokosterone and cynaroside, two compounds from Achyranthis bidentatae radix and Lonicerae japonicae flos, obviously reduced intracellular lipids accumulation in hepatocytes stimulated by non-esterified fatty acid (NEFA). CONCLUSION: MLN improved NASH in MCD-fed mice, and the PGC-1α-PPARα signaling pathway was involved in this process. Moreover, Lonicerae japonicae flos and Achyranthis bidentatae radix contained in MLN contributed greatly to the MLN-provided improvement on NASH.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Animais , Medicamentos de Ervas Chinesas , Lipídeos , Fígado , Metionina/metabolismo , Metionina/farmacologia , Camundongos , Farmacologia em Rede , Hepatopatia Gordurosa não Alcoólica/metabolismo , PPAR alfa/metabolismo
13.
J Med Chem ; 65(14): 9531-9547, 2022 07 28.
Artigo em Inglês | MEDLINE | ID: mdl-35796517

RESUMO

Methionine adenosyltransferase 2A (MAT2A) is a rate-limiting enzyme in the methionine cycle that primarily catalyzes the synthesis of S-adenosylmethionine (SAM) from methionine and adenosine triphosphate (ATP). MAT2A has been recognized as a therapeutic target for the treatment of cancers. Recently, a few MAT2A inhibitors have been reported, and three entered clinical trials to treat solid tumorsor lymphoma with MTAP loss. This review aims to summarize the current understanding of the roles of MAT2A in cancer and the discovery of MAT2A inhibitors. Furthermore, a perspective on the use of MAT2A inhibitors for the treatment of cancer is also discussed. We hope to provide guidance for future drug design and optimization via analysis of the binding modes of known MAT2A inhibitors.


Assuntos
Metionina Adenosiltransferase , Neoplasias , Humanos , Metionina/metabolismo , Metionina Adenosiltransferase/antagonistas & inibidores , Metionina Adenosiltransferase/metabolismo , Neoplasias/tratamento farmacológico , Neoplasias/patologia , S-Adenosilmetionina/metabolismo
14.
Curr Opin Oncol ; 34(5): 546-551, 2022 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-35788128

RESUMO

PURPOSE OF REVIEW: In this review, we summarize the biological roles of methionine, methionine adenosyl transferase 2A (MAT2A) and S -adenosyl methionine (SAM) in methylation reactions during tumorigenesis. Newly emerged inhibitors targeting the methionine-MAT2A-SAM axis will be discussed. RECENT FINDINGS: SAM is the critical and global methyl-donor for methylation reactions regulating gene expression, and in mammalian cells, it is synthesized by MAT2A using methionine. Recent studies have validated methionine and MAT2A as metabolic dependencies of cancer cells because of their essential roles in SAM biosynthesis. MAT2A inhibition leads to synthetic lethality in methylthioadenosine-phosphorylase (MTAP)-deleted cancers, which accounts for 15% of all cancer types. Of note, remarkable progress has been made in developing inhibitors targeting the methionine-MAT2A-SAM axis, as the first-in-class MAT2A inhibitors AG-270 and IDE397 enter clinical trials to treat cancer. SUMMARY: The methionine-MAT2A-SAM axis plays an important role in tumorigenesis by providing SAM as a critical substrate for abnormal protein as well as DNA and RNA methylation in cancer cells. Targeting SAM biosynthesis through MAT2A inhibition has emerged as a novel and promising strategy for cancer therapy.


Assuntos
Neoplasias , Animais , Carcinogênese , Humanos , Mamíferos/metabolismo , Metionina/metabolismo , Metionina Adenosiltransferase/antagonistas & inibidores , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , S-Adenosilmetionina/metabolismo
15.
J Pharm Biomed Anal ; 219: 114944, 2022 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-35863169

RESUMO

One-carbon metabolism is an important metabolic pathway involved in many diseases, such as congenital malformations, tumours, cardiovascular diseases, anaemia, depression, cognitive diseases and liver disease. However, the current methods have specific defects in detecting and qualifying the related compounds of one-carbon metabolism. In this study, a validated method was established to simultaneously quantify 22 one-carbon metabolites & co-factors in human plasma and applied to the study of correlation between one-carbon metabolism and colorectal cancer in human plasma samples, which were from 44 healthy subjects and 55 colorectal cancer patients. The method used ultra-high performance liquid chromatography coupled with triple quadrupole mass spectrometry (UPLC-MS/MS), and the analytes included betaine, L-carnitine, L-cystathionine, L-cysteine, dimethylglycine, DL-homocysteic acid, homocysteine, methionine, pyridoxal hydrochloride, pyridoxamine dihydrochloride, pyridoxine dihydrochloride, S-(5'-Adenosyl)-L-homocysteine, serine, choline chloride, folic acid, glycine, pyridoxal phosphate monohydrate, riboflavin, taurine, 5-methyltetrahydrofolate, S-(5'-adenosyl)-L-methionine disulfate salt, trimethylamine oxide. The developed method was successfully applied to the quantification of 22 one-carbon metabolites & co-factors in human plasma from colorectal cancer patients and healthy individuals. The plasma concentrations of dimethylglycine was significantly decreased in the patients compared with the healthy individuals, while L-cystathionine was increased.


Assuntos
Neoplasias Colorretais , Espectrometria de Massas em Tandem , Carbono/metabolismo , Cromatografia Líquida de Alta Pressão , Cromatografia Líquida/métodos , Cistationina , Homocisteína , Humanos , Metionina/metabolismo , Espectrometria de Massas em Tandem/métodos
16.
PLoS Genet ; 18(7): e1010180, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35816552

RESUMO

Methionine residues are particularly sensitive to oxidation by reactive oxygen or chlorine species (ROS/RCS), leading to the appearance of methionine sulfoxide in proteins. This post-translational oxidation can be reversed by omnipresent protein repair pathways involving methionine sulfoxide reductases (Msr). In the periplasm of Escherichia coli, the enzymatic system MsrPQ, whose expression is triggered by the RCS, controls the redox status of methionine residues. Here we report that MsrPQ synthesis is also induced by copper stress via the CusSR two-component system, and that MsrPQ plays a role in copper homeostasis by maintaining the activity of the copper efflux pump, CusCFBA. Genetic and biochemical evidence suggest the metallochaperone CusF is the substrate of MsrPQ and our study reveals that CusF methionines are redox sensitive and can be restored by MsrPQ. Thus, the evolution of a CusSR-dependent synthesis of MsrPQ allows conservation of copper homeostasis under aerobic conditions by maintenance of the reduced state of Met residues in copper-trafficking proteins.


Assuntos
Proteínas de Escherichia coli , Escherichia coli , Cobre/metabolismo , Proteínas de Transporte de Cobre/genética , Escherichia coli/metabolismo , Proteínas de Escherichia coli/metabolismo , Metalochaperonas/genética , Metalochaperonas/metabolismo , Metionina/metabolismo , Oxirredução , Periplasma/metabolismo
17.
Genes (Basel) ; 13(7)2022 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-35885946

RESUMO

Methionine adenosyltransferase I/III deficiency is an inborn error of metabolism due to mutations in the MAT1A gene. It is the most common cause of hypermethioninemia in newborn screening. Heterozygotes are often asymptomatic. In contrast, homozygous or compound heterozygous individuals can develop severe neurological symptoms. Less than 70 cases with biallelic variants have been reported worldwide. A methionine-restricted diet is recommended if methionine levels are above 500-600 µmol/L. In this study, we report on a female patient identified with elevated methionine concentrations in a pilot newborn screening program. The patient carries a previously described variant c.1132G>A (p.Gly378Ser) in homozygosity. It is located at the C-terminus of MAT1A. In silico analysis suggests impaired protein stability by ß-turn disruption. On a methionine-restricted diet, her serum methionine concentration ranged between 49-605 µmol/L (median 358 µmol/L). Her clinical course was characterized by early-onset muscular hypotonia, mild developmental delay, delayed myelination and mild periventricular diffusion interference in MRI. At 21 months, the girl showed age-appropriate neurological development, but progressive diffusion disturbances in MRI. Little is known about the long-term outcome of this disorder and the necessity of treatment. Our case demonstrates that neurological symptoms can be transient and even patients with initial neurologic manifestations can show normal development under dietary management.


Assuntos
Metionina Adenosiltransferase , Triagem Neonatal , Erros Inatos do Metabolismo dos Aminoácidos , Feminino , Glicina N-Metiltransferase/deficiência , Glicina N-Metiltransferase/genética , Humanos , Recém-Nascido , Metionina/metabolismo , Metionina Adenosiltransferase/genética , Metionina Adenosiltransferase/metabolismo
18.
Int J Mol Sci ; 23(13)2022 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-35806160

RESUMO

Glioblastoma is a fatal brain tumor with a bleak prognosis. The use of chemotherapy, primarily the alkylating agent temozolomide, coupled with radiation and surgical resection, has provided some benefit. Despite this multipronged approach, average patient survival rarely extends beyond 18 months. Challenges to glioblastoma treatment include the identification of functional pharmacologic targets as well as identifying drugs that can cross the blood-brain barrier. To address these challenges, current research efforts are examining metabolic differences between normal and tumor cells that could be targeted. Among the metabolic differences examined to date, the apparent addiction to exogenous methionine by glioblastoma tumors is a critical factor that is not well understood and may serve as an effective therapeutic target. Others have proposed this property could be exploited by methionine dietary restriction or other approaches to reduce methionine availability. However, methionine links the tumor microenvironment with cell metabolism, epigenetic regulation, and even mitosis. Therefore methionine depletion could result in complex and potentially undesirable responses, such as aneuploidy and the aberrant expression of genes that drive tumor progression. If methionine manipulation is to be a therapeutic strategy for glioblastoma patients, it is essential that we enhance our understanding of the role of methionine in the tumor microenvironment.


Assuntos
Neoplasias Encefálicas , Glioblastoma , Antineoplásicos Alquilantes/uso terapêutico , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/terapia , Epigênese Genética , Glioblastoma/genética , Humanos , Metionina/metabolismo , Temozolomida/uso terapêutico , Microambiente Tumoral
19.
J Mech Behav Biomed Mater ; 133: 105355, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35839634

RESUMO

Rumen protected amino acids are supplements that can enhance ruminal performance, yet the coating designed to protect the amino acids might also lead to different effects. Methionine is an essential methyl donor to synthesize protein, and little data exists on the effects of coating materials on its bioavailability. The purpose of this study was to estimate the effect of rumen-protected methionine (RPM) coatings with different ratios of acrylic resin IV (AR), ethyl cellulose (EC), and a mixture of AR and EC (AREC). Fifteen RPMs were prepared according to a single factor design, with 5 proportions each of AR, EC, and AREC to DL-methionine (DL-Met). Twelve hybrid small-tailed Han sheep with rumen fistula were utilized to evaluate in situ escape of RPMs, followed by in vitro abomasum-intestinal release of the RPMs. The results showed a regular variation in both ruminal disappearance and gastrointestinal release of RPMs with different coating prototypes and retention time. The RPMs that were EC and AREC coated presented high bioavailability compared to those with AR. Bioavailability of RPMs was optimal with the 2:20 AREC: DL-Met ratio, when the proportion of AR:EC is 1:1. Additionally, RPMs with a 1:3 ratio of AR:EC confirmed the optimum effect for the RPM of 2:20 AREC: DL-Met. In conclusion, an RPM with a lower AREC ratio coating can achieve better bioavailability and is synergistic to those with EC and AR.


Assuntos
Metionina , Rúmen , Aminoácidos , Animais , Disponibilidade Biológica , Dieta/veterinária , Suplementos Nutricionais , Metionina/metabolismo , Metionina/farmacologia , Rúmen/metabolismo , Ovinos
20.
Cell Rep ; 40(3): 111120, 2022 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-35858556

RESUMO

Pluripotent stem cells (PSCs) exhibit a unique feature that requires S-adenosylmethionine (SAM) for the maintenance of their pluripotency. Methionine deprivation in the medium causes a reduction in intracellular SAM, thus rendering PSCs in a state potentiated for differentiation. In this study, we find that methionine deprivation triggers a reduction in intracellular protein-bound Zn content and upregulation of Zn exporter SLC30A1 in PSCs. Culturing PSCs in Zn-deprived medium results in decreased intracellular protein-bound Zn content, reduced cell growth, and potentiated differentiation, which partially mimics methionine deprivation. PSCs cultured under Zn deprivation exhibit an altered methionine metabolism-related metabolite profile. We conclude that methionine deprivation potentiates differentiation partly by lowering cellular Zn content. We establish a protocol to generate functional pancreatic ß cells by applying methionine and Zn deprivation. Our results reveal a link between Zn signaling and methionine metabolism in the regulation of cell fate in PSCs.


Assuntos
Células-Tronco Pluripotentes , Zinco , Diferenciação Celular/fisiologia , Metionina/metabolismo , Células-Tronco Pluripotentes/metabolismo , S-Adenosilmetionina/metabolismo , Transdução de Sinais , Zinco/metabolismo
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