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1.
Oncogene ; 2021 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-34667275

RESUMO

Calcineurin is a calcium- and calmodulin-dependent serine/threonine protein phosphatase that connects the Ca2+-dependent signalling to multiple cellular responses. Calcineurin inhibitors (CNIs) have been widely used to suppress immune response in allograft patients. However, CNIs significantly increase cancer incidence in transplant recipients compared with the general population. Accumulating evidence suggests that CNIs may promote the malignant transformation of cancer cells in addition to its role in immunosuppression, but the underlying mechanisms remain poorly understood. Here, we show that calcineurin interacts with pyruvate dehydrogenase complex (PDC), a mitochondrial gatekeeper enzyme that connects two key metabolic pathways of cells, glycolysis and the tricarboxylic acid cycle. Mitochondrial-localized calcineurin dephosphorylates PDHA1 at Ser232, Ser293 and Ser300, and thus enhances PDC enzymatic activity, remodels cellular glycolysis and oxidative phosphorylation, and suppresses cancer cell proliferation. Hypoxia attenuates mitochondrial translocation of calcineurin to promote PDC inactivation. Moreover, CNIs promote metabolic remodelling and the Warburg effect by blocking calcineurin-mediated PDC activation in cancer cells. Our findings indicate that calcineurin is a critical regulator of mitochondrial metabolism and suggest that CNIs may promote tumorigenesis through inhibition of the calcineurin-PDC pathway.

2.
Nat Commun ; 12(1): 5716, 2021 09 29.
Artigo em Inglês | MEDLINE | ID: mdl-34588438

RESUMO

Mutations in SPOP E3 ligase gene are reportedly associated with genome-wide DNA hypermethylation in prostate cancer (PCa) although the underlying mechanisms remain elusive. Here, we demonstrate that SPOP binds and promotes polyubiquitination and degradation of histone methyltransferase and DNMT interactor GLP. SPOP mutation induces stabilization of GLP and its partner protein G9a and aberrant upregulation of global DNA hypermethylation in cultured PCa cells and primary PCa specimens. Genome-wide DNA methylome analysis shows that a subset of tumor suppressor genes (TSGs) including FOXO3, GATA5, and NDRG1, are hypermethylated and downregulated in SPOP-mutated PCa cells. DNA methylation inhibitor 5-azacytidine effectively reverses expression of the TSGs examined, inhibits SPOP-mutated PCa cell growth in vitro and in mice, and enhances docetaxel anti-cancer efficacy. Our findings reveal the GLP/G9a-DNMT module as a mediator of DNA hypermethylation in SPOP-mutated PCa. They suggest that SPOP mutation could be a biomarker for effective treatment of PCa with DNA methylation inhibitor alone or in combination with taxane chemotherapeutics.


Assuntos
Metilação de DNA/genética , Antígenos de Histocompatibilidade/metabolismo , Histona-Lisina N-Metiltransferase/metabolismo , Proteínas Nucleares/genética , Neoplasias da Próstata/genética , Proteínas Repressoras/genética , Animais , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Azacitidina/farmacologia , Azacitidina/uso terapêutico , Linhagem Celular Tumoral , DNA (Citosina-5-)-Metiltransferases/antagonistas & inibidores , DNA (Citosina-5-)-Metiltransferases/metabolismo , Metilação de DNA/efeitos dos fármacos , Docetaxel/farmacologia , Docetaxel/uso terapêutico , Regulação para Baixo/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/genética , Sinergismo Farmacológico , Epigênese Genética/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Genes Supressores de Tumor , Humanos , Masculino , Camundongos , Mutação , Proteínas Nucleares/metabolismo , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/patologia , Estabilidade Proteica/efeitos dos fármacos , Proteólise/efeitos dos fármacos , Proteínas Repressoras/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
3.
Front Genet ; 12: 630650, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34504512

RESUMO

Prader-Willi syndrome (PWS) is a complex genetic syndrome caused by the loss of function of genes in 15q11-q13 that are subject to regulation by genomic imprinting and expressed from the paternal allele only. The main clinical features of PWS patients are hypotonia during the neonatal and infantile stages, accompanied by delayed neuropsychomotor development, hyperphagia, obesity, hypogonadism, short stature, small hands and feet, mental disabilities, and behavioral problems. However, PWS has a clinical overlap with other disorders, especially those with other gene variations or chromosomal imbalances but sharing part of the similar clinical manifestations with PWS, which are sometimes referred to as Prader-Willi syndrome-like (PWS-like) disorders. Furthermore, it is worth mentioning that significant obesity as a consequence of hyperphagia in PWS usually develops between the ages of 1 and 6 years, which makes early diagnosis difficult. Thus, PWS is often not clinically recognized in infants and, on the other hand, may be wrongly suspected in obese and intellectually disabled patients. Therefore, an accurate investigation is necessary to differentiate classical PWS from PWS-like phenotypes, which is imperative for further treatment. For PWS, it is usually sporadic, and very rare family history and affected siblings have been described. Here, we report the clinical and molecular findings in a three-generation family with a novel 550-kb microdeletion affecting the chromosome 15 imprinting center (IC). Overall, the present study finds that the symptoms of our patient are somewhat different from those of typical PWS cases diagnosed and given treatment in our hospital. The familial occurrence and clinical features were challenging to our diagnostic strategy. The microdeletion included a region within the complex small nuclear ribonucleoprotein polypeptide protein N (SNRPN) gene locus encompassing the PWS IC and was identified by using a variety of techniques. Haplotype studies suggest that the IC microdeletion was vertically transmitted from an unaffected paternal grandmother to an unaffected father and then caused PWS in two sibling grandchildren when the IC microdeletion was inherited paternally. Based on the results of our study, preimplantation genetic diagnosis (PGD) was applied successfully to exclude imprinting deficiency in preimplantation embryos before transfer into the mother's uterus. Our study may be especially instructive regarding accurate diagnosis, differential diagnosis, genetic counseling, and PGD for familial PWS patients.

4.
Front Immunol ; 12: 679897, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34367139

RESUMO

Intestinal microbiota dysbiosis is an established characteristic of ulcerative colitis (UC). Regulating the gut microbiota is an attractive alternative UC treatment strategy, considering the potential adverse effects of synthetic drugs used to treat UC. Kaempferol (Kae) is an anti-inflammatory and antioxidant flavonoid derived from a variety of medicinal plants. In this study, we determined the efficacy and mechanism of action of Kae as an anti-UC agent in dextran sulfate sodium (DSS)-induced colitis mice. DSS challenge in a mouse model of UC led to weight loss, diarrhea accompanied by mucous and blood, histological abnormalities, and shortening of the colon, all of which were significantly alleviated by pretreatment with Kae. In addition, intestinal permeability was shown to improve using fluorescein isothiocyanate (FITC)-dextran administration. DSS-induced destruction of the intestinal barrier was also significantly prevented by Kae administration via increases in the levels of ZO-1, occludin, and claudin-1. Furthermore, Kae pretreatment decreased the levels of IL-1ß, IL-6, and TNF-α and downregulated transcription of an array of inflammatory signaling molecules, while it increased IL-10 mRNA expression. Notably, Kae reshaped the intestinal microbiome by elevating the Firmicutes to Bacteroidetes ratio; increasing the linear discriminant analysis scores of beneficial bacteria, such as Prevotellaceae and Ruminococcaceae; and reducing the richness of Proteobacteria in DSS-challenged mice. There was also an evident shift in the profile of fecal metabolites in the Kae treatment group. Serum LPS levels and downstream TLR4-NF-κB signaling were downregulated by Kae supplementation. Moreover, fecal microbiota transplantation from Kae-treated mice to the DSS-induced mice confirmed the effects of Kae on modulating the gut microbiota to alleviate UC. Therefore, Kae may exert protective effects against colitis mice through regulating the gut microbiota and TLR4-related signaling pathways. This study demonstrates the anti-UC effects of Kae and its potential therapeutic mechanisms, and offers novel insights into the prevention of inflammatory diseases using natural products.


Assuntos
Anti-Inflamatórios/farmacologia , Colite/metabolismo , Microbioma Gastrointestinal/efeitos dos fármacos , Quempferóis/farmacologia , NF-kappa B/metabolismo , Transdução de Sinais/efeitos dos fármacos , Receptor 4 Toll-Like/metabolismo , Animais , Biomarcadores , Colite/etiologia , Colite/patologia , Colite/terapia , Sulfato de Dextrana/efeitos adversos , Modelos Animais de Doenças , Transplante de Microbiota Fecal , Feminino , Mucosa Intestinal/metabolismo , Mucosa Intestinal/microbiologia , Lipopolissacarídeos/efeitos adversos , Camundongos , Permeabilidade , RNA Ribossômico 16S
5.
J Immunother Cancer ; 9(7)2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34326168

RESUMO

BACKGROUND: Tryptophan catabolites suppress immunity. Therefore, blocking tryptophan catabolism with indoleamine 2,3-dioxygenase (IDO) inhibitors is pursued as an anticancer strategy. METHODS: The intracellular level of tryptophan and kynurenine was detected by mass spectrum analysis. The effect of tryptophan and IDO inhibitors on cell surface programmed cell death protein 1 (PD-1) level were measured by flow cytometry. A set of biochemical analyses were used to figure out the underlying mechanism. In vitro co-culture system, syngeneic mouse models, immunofluorescent staining, and flow cytometry analysis were employed to investigate the role of tryptophan and IDO inhibitor in regulating the cytotoxicity of CD8+ T cells. RESULTS: Here, we reported that IDO inhibitors activated CD8+ T cells also by accumulating tryptophan that downregulated PD-1. Tryptophan and IDO inhibitors administration, both increased intracellular tryptophan, and tryptophanyl-tRNA synthetase (WARS) overexpression decreased Jurkat and mice CD8+ T cell surface PD-1. Mechanistically, WARS tryptophanylated lysine 1136 of and activated E3 ligase TRIP12 to degrade NFATc1, a PD-1 transcription activator. SIRT1 de-tryptophanylated TRIP12 and reversed the effects of tryptophan and WARS on PD-1. Tryptophan or IDO inhibitors potentiated CD8+ T cells to induce apoptosis of co-cultured cancer cells, increased cancer-infiltrating CD8+ T cells and slowed down tumor growth of lung cancer in mice. CONCLUSIONS: Our results revealed the immune-activating efficacy of tryptophan, and suggested tryptophan supplemental may benefit IDO inhibitors and PD-1 blockade during anticancer treatments.

6.
Cell Death Dis ; 12(7): 634, 2021 06 19.
Artigo em Inglês | MEDLINE | ID: mdl-34148062

RESUMO

Signal transducer and activator 5a (STAT5A) is a classical transcription factor that plays pivotal roles in various biological processes, including tumor initiation and progression. A fraction of STAT5A is localized in the mitochondria, but the biological functions of mitochondrial STAT5A remain obscure. Here, we show that STAT5A interacts with pyruvate dehydrogenase complex (PDC), a mitochondrial gatekeeper enzyme connecting two key metabolic pathways, glycolysis and the tricarboxylic acid cycle. Mitochondrial STAT5A disrupts PDC integrity, thereby inhibiting PDC activity and remodeling cellular glycolysis and oxidative phosphorylation. Mitochondrial translocation of STAT5A is increased under hypoxic conditions. This strengthens the Warburg effect in cancer cells and promotes in vitro cell growth under hypoxia and in vivo tumor growth. Our findings indicate distinct pro-oncogenic roles of STAT5A in energy metabolism, which is different from its classical function as a transcription factor.


Assuntos
Mitocôndrias/enzimologia , Complexo Piruvato Desidrogenase/metabolismo , Fator de Transcrição STAT5/metabolismo , Proteínas Supressoras de Tumor/metabolismo , Neoplasias do Colo do Útero/enzimologia , Efeito Warburg em Oncologia , Trifosfato de Adenosina/metabolismo , Animais , Proliferação de Células , Feminino , Glicólise , Células HEK293 , Células HeLa , Humanos , Camundongos Endogâmicos BALB C , Camundongos Nus , Mitocôndrias/genética , Mitocôndrias/patologia , Fosforilação Oxidativa , Consumo de Oxigênio , Fator de Transcrição STAT5/genética , Carga Tumoral , Hipóxia Tumoral , Microambiente Tumoral , Proteínas Supressoras de Tumor/genética , Neoplasias do Colo do Útero/genética , Neoplasias do Colo do Útero/patologia
7.
Nat Commun ; 12(1): 3428, 2021 06 08.
Artigo em Inglês | MEDLINE | ID: mdl-34103526

RESUMO

Dysregulated extravillous trophoblast invasion and proliferation are known to increase the risk of recurrent spontaneous abortion (RSA); however, the underlying mechanism remains unclear. Herein, in our retrospective observational case-control study we show that villous samples from RSA patients, compared to healthy controls, display reduced succinate dehydrogenase complex iron sulfur subunit (SDHB) DNA methylation, elevated SDHB expression, and reduced succinate levels, indicating that low succinate levels correlate with RSA. Moreover, we find high succinate levels in early pregnant women are correlated with successful embryo implantation. SDHB promoter methylation recruited MBD1 and excluded c-Fos, inactivating SDHB expression and causing intracellular succinate accumulation which mimicked hypoxia in extravillous trophoblasts cell lines JEG3 and HTR8 via the PHD2-VHL-HIF-1α pathway; however, low succinate levels reversed this effect and increased the risk of abortion in mouse model. This study reveals that abnormal metabolite levels inhibit extravillous trophoblast function and highlights an approach for RSA intervention.


Assuntos
Aborto Habitual/metabolismo , Vilosidades Coriônicas/metabolismo , Ácido Succínico/metabolismo , Aborto Habitual/enzimologia , Aborto Habitual/genética , Animais , Estudos de Casos e Controles , Hipóxia Celular , Linhagem Celular Tumoral , Ilhas de CpG/genética , Metilação de DNA/genética , Proteínas de Ligação a DNA/metabolismo , Feminino , Regulação da Expressão Gênica , Glicólise , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Metaboloma , Camundongos Endogâmicos C57BL , Gravidez , Regiões Promotoras Genéticas/genética , Ligação Proteica , Proteínas Proto-Oncogênicas c-fos/metabolismo , Fatores de Risco , Succinato Desidrogenase/genética , Succinato Desidrogenase/metabolismo , Fatores de Transcrição/metabolismo , Transcrição Genética , Trofoblastos/metabolismo , Trofoblastos/patologia
8.
Nat Metab ; 3(6): 859-875, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-34140692

RESUMO

Global histone acetylation varies with changes in the nutrient and cell cycle phases; however, the mechanisms connecting these variations are not fully understood. Herein, we report that nutrient-related and cell-cycle-regulated nuclear acetate regulates global histone acetylation. Histone deacetylation-generated acetate accumulates in the nucleus and induces histone hyperacetylation. The nuclear acetate levels were controlled by glycolytic enzyme triosephosphate isomerase 1 (TPI1). Cyclin-dependent kinase 2 (CDK2), which is phosphorylated and activated by nutrient-activated mTORC1, phosphorylates TPI1 Ser 117 and promotes nuclear translocation of TPI1, decreases nuclear dihydroxyacetone phosphate (DHAP) and induces nuclear acetate accumulation because DHAP scavenges acetate via the formation of 1-acetyl-DHAP. CDK2 accumulates in the cytosol during the late G1/S phases. Inactivation or blockade of nuclear translocation of TPI1 abrogates nutrient-dependent and cell-cycle-dependent global histone acetylation, chromatin condensation, gene transcription and DNA replication. These results identify the mechanism of maintaining global histone acetylation by nutrient and cell cycle signals.


Assuntos
Ciclo Celular/fisiologia , Núcleo Celular/metabolismo , Fosfato de Di-Hidroxiacetona/metabolismo , Histonas/metabolismo , Nutrientes/metabolismo , Transdução de Sinais , Acetatos/metabolismo , Acetilação , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Cromatina/genética , Cromatina/metabolismo , Replicação do DNA , Humanos , Fosforilação , Transcrição Genética
9.
Shanghai Kou Qiang Yi Xue ; 30(1): 100-103, 2021 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-33907790

RESUMO

PURPOSE: To study the clinical prognosis of laterally luxated primary teeth after 6-month follow-up without treatment. METHODS: Patients with laterally luxated primary teeth, visiting Department of Pediatric Dentistry, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine from March 2018 to March 2019, were selected for the study. Based on the inclusion and exclusion criteria, totally 45 patients with 57 primary teeth were included. The reposition outcomes and pulp prognosis were reviewed at the end of follow-up. The data were analyzed using SPSS 23.0 software package. RESULTS: During a 6-month follow-up, 92.98% of the luxated teeth showed spontaneous reposition while only 31.58% of the traumatic teeth were back to the original position. Regarding the pulp healing complications, 54.39% of the luxated teeth exhibited no clinical symptoms, and 14.04% of the evaluated teeth displayed pulp canal obliteration, and pulp necrosis happened in 31.58% of the injured teeth. There was significant difference in the reposition outcome between labial-palatal luxation and mesial-distal luxation(P<0.05), but no significant difference was found in pulp prognosis between the two luxation types(P>0.05). Spontaneous reposition and crown discoloration observed in most of the evaluated cases, were the earliest signs after one-month follow-up. Periapical translucent image and root resorption due to periapical inflammation showed within the first three months after injury, pulp canal obliteration appeared after 6 months. CONCLUSIONS: In general, most of the laterally luxated teeth left without treatment can reposition spontaneously and show lower incidence of pulp necrosis compared with mature permanent teeth in half a year after injury. The direction of luxation does not affect pulp prognosis but has an influence on teeth reposition procedure.


Assuntos
Avulsão Dentária , Criança , China , Necrose da Polpa Dentária , Humanos , Prognóstico , Estudos Retrospectivos , Avulsão Dentária/diagnóstico por imagem , Dente Decíduo
10.
Front Cell Dev Biol ; 9: 619475, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33763417

RESUMO

Nonsense variants in KIDINS220/ARMS were identified as the main cause of spastic paraplegia, intellectual disability, nystagmus, and obesity (SINO) syndrome, a rare disease with birth defects in brachycephaly, neurological disorder, and obesity. The cause of neural cell dysfunction by KIDINS220/ARMS were extensively studied while the cause of obesity in SINO syndrome remains elusive. Here, we identified KIDINS220/ARMS as an adipocyte differentiation-regulating gene. A Chinese family, mother and her two sons, all showed severe symptoms of SINO syndrome. G-banding karyotyping, chromosome microarray analysis, and whole exome sequencing revealed a novel amber mutation, c.3934G>T (p. E1312X), which was close to the C-terminal region of KIDINS220/ARMS and resulted in the premature of the protein. Both the mRNA and protein levels of KIDINS220/ARMS gradually decreased during adipocyte differentiation. Knockdown of KINDINS220/ARMS could prompt adipocyte differentiation and lipid accumulation while overexpression of KIDINS220/ARMS decrease the rate of matured adipocytes. Furthermore, we demonstrated that KIDINS220/ARMS inhibits adipocyte maturation through sustained extracellular signal-regulated kinase signaling. In conclusion, this is the first report about a vertical heredity of severe dominant pathogenic mutation of KIDINS220/ARMS, suggested that KIDINS220/ARMS played a negative role in adipocyte maturation, explained the cause of obesity in SINO syndrome and could highlight the importance of adipocyte differentiation in neuron functions.

11.
Signal Transduct Target Ther ; 6(1): 54, 2021 02 09.
Artigo em Inglês | MEDLINE | ID: mdl-33558457

RESUMO

In addition to their use in relieving the symptoms of various diseases, ketogenic diets (KDs) have also been adopted by healthy individuals to prevent being overweight. Herein, we reported that prolonged KD exposure induced cardiac fibrosis. In rats, KD or frequent deep fasting decreased mitochondrial biogenesis, reduced cell respiration, and increased cardiomyocyte apoptosis and cardiac fibrosis. Mechanistically, increased levels of the ketone body ß-hydroxybutyrate (ß-OHB), an HDAC2 inhibitor, promoted histone acetylation of the Sirt7 promoter and activated Sirt7 transcription. This in turn inhibited the transcription of mitochondrial ribosome-encoding genes and mitochondrial biogenesis, leading to cardiomyocyte apoptosis and cardiac fibrosis. Exogenous ß-OHB administration mimicked the effects of a KD in rats. Notably, increased ß-OHB levels and SIRT7 expression, decreased mitochondrial biogenesis, and increased cardiac fibrosis were detected in human atrial fibrillation heart tissues. Our results highlighted the unknown detrimental effects of KDs and provided insights into strategies for preventing cardiac fibrosis in patients for whom KDs are medically necessary.

12.
AMB Express ; 10(1): 101, 2020 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-32472368

RESUMO

Both steatosis and inflammation are key pathological events in the progression of non-alcoholic fatty liver disease (NAFLD). Probiotics are beneficial for the prevention and treatment of NAFLD. Bifidobacterium animalis subsp. lactis V9 (V9) is a newly isolated strain with favorable probiotic properties. The study aims to evaluate the effects and mechanisms of V9 on the hepatic steatosis and inflammatory responses in a rat model of NAFLD induced by high-fat diets (HFD). Our results showed that administration of V9 significantly attenuated the HFD-induced increases in alanine transaminase (ALT) and aspartate aminotransferase (AST) levels, resulting in alleviated hepatic steatosis. V9 supplementation reduced the accumulation of hepatic triglyceride and free fatty acid,while increasing the levels of glycogen. Serum levels of glucose were also decreased in HFD rats administrated with V9. Meanwhile, the transcription of SREBP-1c and FAS was reduced, and the hepatic expression of phosphorylated-AMPK and PPAR-α was restored after V9 administration. V9 suppressed the production of inflammatory cytokines (e.g. IL-6, IL-1ß, and TNF-α) in HFD-fed rats. The anti-inflammatory effects of V9 was found to be associated with the inhibition of hepatic expression of TLR4, TLR9, NLRP3, and ASC mRNA. Furthermore, the activation of ERK, JNK, AKT and NF-κB were suppressed by V9 treatment. These results indicate that Bifidobacterium lactis V9 improves NAFLD by regulating de novo lipid synthesis and suppressing inflammation through AMPK and TLR-NF-κB pathways, respectively.

13.
Immunopharmacol Immunotoxicol ; 42(3): 280-285, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32326777

RESUMO

Background: Sepsis is life-threatening organ dysfunction caused by a dysregulated host response to infection. Inflammatory response and oxidative stress play an important role in the pathophysiological process of sepsis. Thioredoxin-1 (Trx-1) is a small ubiquitous thiol protein with redox/inflammation modulatory properties relevant to the pathogenesis of sepsis. We therefore investigated the expression level and significance of Trx-1, inflammatory factors and oxidative stress in peripheral blood of sepsis patients, and to explore Trx-1 relationship with inflammatory factors and oxidative stress.Methods: Plasma samples were collected from patients with sepsis and those with healthy control. Enzyme-linked immunosorbent assays (ELISA) were used to detect for interleukin (IL-1ß), IL-6, tumor necrosis factor (TNF-α), E-selectin, endothelin-1 (ET-1), thioredoxin-1, C-reactive protein (CRP), procalcitonin (PCT) for human plasma samples; RT-PCR detection of Trx-1 and thioredoxin-interacting protein (TXNIP) mRNA levels. Colorimetric assay for glutathione (GSH) and malondialdehyde (MDA) expression level in peripheral blood of patients with sepsis; Disease severity was assessed as APACHE II.Results: The expression levels of Trx-1, inflammatory factors and oxidative stress in plasma of patients with sepsis were significantly increased, TXNIP opposite.Conclusion: Our results show that Trx-1 play important role in inflammation and oxidative stress in sepsis patients. Trx-1 may be a potential therapeutic target in sepsis.


Assuntos
Citocinas/genética , Expressão Gênica , Estresse Oxidativo/imunologia , Sepse/sangue , Tiorredoxinas/genética , Estudos de Casos e Controles , Estudos de Coortes , Citocinas/sangue , Ensaio de Imunoadsorção Enzimática , Feminino , Expressão Gênica/imunologia , Humanos , Masculino , Pessoa de Meia-Idade , Estresse Oxidativo/genética , Reação em Cadeia da Polimerase em Tempo Real , Sepse/imunologia , Tiorredoxinas/sangue
14.
Plant Physiol Biochem ; 150: 80-89, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32126511

RESUMO

Genome resequencing was carried out on two varieties of flue-cured tobacco (LY1306 and Qinyan 96), one variety of sun-cured tobacco (Wanmao 3), and one variety of air-cured Maryland tobacco (Wufeng 1), for a comparative analysis of genomic variation across the four varieties. Single nucleotide polymorphisms (SNPs), insertions and deletions (InDels), structural variations (SVs), and copy-number variations (CNVs) were then identified in each tobacco variety. Furthermore, a functional analysis of mutated genes was carried out. Through in-depth comparative analysis of genomes of different tobacco varieties, we identified genome variations in a number of SNPs, InDels, SVs, and CNVs, respectively. Computational analysis to predict the function of mutated genes containing these differential SNPs, InDels, SVs, and CNVs showed that they were mainly involved in different functions, such as carbohydrate metabolism and secondary metabolites biosynthesis. We mainly focused on genes that were involved in the biosynthesis of secondary metabolites and nicotine metabolism. In addition, we identified five simple sequence repeat (SSR)-based markers and verified them by PCR amplification in 10 tobacco varieties. Taken together, our study increases the understanding of genetic differences between tobacco types or varieties and identifies five SSR markers to classify tobacco varieties or types.


Assuntos
Variação Genética , Genoma de Planta , Sequenciamento de Nucleotídeos em Larga Escala , Repetições de Microssatélites , Tabaco , Genoma de Planta/genética , Genômica , Mutação INDEL , Repetições de Microssatélites/genética , Polimorfismo de Nucleotídeo Único , Tabaco/classificação , Tabaco/genética
15.
Cell Metab ; 31(3): 580-591.e5, 2020 03 03.
Artigo em Inglês | MEDLINE | ID: mdl-32032542

RESUMO

It is well documented that the rate of aging can be slowed, but it remains unclear to which extent aging-associated conditions can be reversed. How the interface of immunity and metabolism impinges upon the diabetes pandemic is largely unknown. Here, we show that NLRP3, a pattern recognition receptor, is modified by acetylation in macrophages and is deacetylated by SIRT2, an NAD+-dependent deacetylase and a metabolic sensor. We have developed a cell-based system that models aging-associated inflammation, a defined co-culture system that simulates the effects of inflammatory milieu on insulin resistance in metabolic tissues during aging, and aging mouse models; and demonstrate that SIRT2 and NLRP3 deacetylation prevent, and can be targeted to reverse, aging-associated inflammation and insulin resistance. These results establish the dysregulation of the acetylation switch of the NLRP3 inflammasome as an origin of aging-associated chronic inflammation and highlight the reversibility of aging-associated chronic inflammation and insulin resistance.


Assuntos
Envelhecimento/patologia , Inflamassomos/metabolismo , Inflamação/patologia , Resistência à Insulina , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Acetilação , Sequência de Aminoácidos , Animais , Doença Crônica , Modelos Animais de Doenças , Glucose/metabolismo , Homeostase , Camundongos Endogâmicos C57BL , Camundongos Knockout , Modelos Biológicos , Proteína 3 que Contém Domínio de Pirina da Família NLR/química , Hipernutrição/patologia , Peptídeos/química , Sirtuína 2/metabolismo
16.
EMBO Mol Med ; 12(3): e9469, 2020 03 06.
Artigo em Inglês | MEDLINE | ID: mdl-32003121

RESUMO

Hyperhomocysteinemia is a common metabolic disorder that imposes major adverse health consequences. Reducing homocysteine levels, however, is not always effective against hyperhomocysteinemia-associated pathologies. Herein, we report the potential roles of methionyl-tRNA synthetase (MARS)-generated homocysteine signals in neural tube defects (NTDs) and congenital heart defects (CHDs). Increased copy numbers of MARS and/or MARS2 were detected in NTD and CHD patients. MARSs sense homocysteine and transmit its signal by inducing protein lysine (N)-homocysteinylation. Here, we identified hundreds of novel N-homocysteinylated proteins. N-homocysteinylation of superoxide dismutases (SOD1/2) provided new mechanistic insights for homocysteine-induced oxidative stress, apoptosis and Wnt signalling deregulation. Elevated MARS expression in developing and proliferating cells sensitizes them to the effects of homocysteine. Targeting MARSs using the homocysteine analogue acetyl homocysteine thioether (AHT) reversed MARS efficacy. AHT lowered NTD and CHD onsets in retinoic acid-induced and hyperhomocysteinemia-induced animal models without affecting homocysteine levels. We provide genetic and biochemical evidence to show that MARSs are previously overlooked genetic determinants and key pathological factors of hyperhomocysteinemia, and suggest that MARS inhibition represents an important medicinal approach for controlling hyperhomocysteinemia-associated diseases.


Assuntos
Cardiopatias Congênitas , Hiper-Homocisteinemia , Metionina tRNA Ligase/antagonistas & inibidores , Defeitos do Tubo Neural , Animais , Feminino , Cardiopatias Congênitas/prevenção & controle , Homocisteína , Humanos , Hiper-Homocisteinemia/genética , Recém-Nascido , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Defeitos do Tubo Neural/prevenção & controle , Ratos , Ratos Sprague-Dawley , Estados Unidos
17.
Nat Commun ; 11(1): 174, 2020 01 10.
Artigo em Inglês | MEDLINE | ID: mdl-31924757

RESUMO

mTORC1 is an important regulator of muscle mass but how it is modulated by oxygen and nutrients is not completely understood. We show that loss of the prolyl hydroxylase domain isoform 1 oxygen sensor in mice (PHD1KO) reduces muscle mass. PHD1KO muscles show impaired mTORC1 activation in response to leucine whereas mTORC1 activation by growth factors or eccentric contractions was preserved. The ability of PHD1 to promote mTORC1 activity is independent of its hydroxylation activity but is caused by decreased protein content of the leucyl tRNA synthetase (LRS) leucine sensor. Mechanistically, PHD1 interacts with and stabilizes LRS. This interaction is promoted during oxygen and amino acid depletion and protects LRS from degradation. Finally, elderly subjects have lower PHD1 levels and LRS activity in muscle from aged versus young human subjects. In conclusion, PHD1 ensures an optimal mTORC1 response to leucine after episodes of metabolic scarcity.


Assuntos
Leucina-tRNA Ligase/metabolismo , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Músculos/metabolismo , Pró-Colágeno-Prolina Dioxigenase/metabolismo , Adulto , Idoso , Envelhecimento/metabolismo , Aminoácidos/metabolismo , Animais , Modelos Animais de Doenças , Feminino , Células HEK293 , Humanos , Hidroxilação , Prolina Dioxigenases do Fator Induzível por Hipóxia/metabolismo , Leucina/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Desenvolvimento Muscular , Músculos/patologia , Oxigênio/metabolismo , Pró-Colágeno-Prolina Dioxigenase/genética , Transdução de Sinais
18.
Cancer Res ; 80(2): 319-333, 2020 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-31690668

RESUMO

The tumorigenic role and underlying mechanisms of lipid accumulation, commonly observed in many cancers, remain insufficiently understood. In this study, we identified an AMP-activated protein kinase (AMPK)-GATA-binding protein 3 (GATA3)-enoyl-CoA hydratase short-chain 1 (ECHS1) pathway that induces lipid accumulation and promotes cell proliferation in clear cell renal cell carcinoma (ccRCC). Decreased expression of ECHS1, which is responsible for inactivation of fatty acid (FA) oxidation and activation of de novo FA synthesis, positively associated with ccRCC progression and predicted poor patient survival. Mechanistically, ECHS1 downregulation induced FA and branched-chain amino acid (BCAA) accumulation, which inhibited AMPK-promoted expression of GATA3, a transcriptional activator of ECHS1. BCAA accumulation induced activation of mTORC1 and de novo FA synthesis, and promoted cell proliferation. Furthermore, GATA3 expression phenocopied ECHS1 in predicting ccRCC progression and patient survival. The AMPK-GATA3-ECHS1 pathway may offer new therapeutic approaches and prognostic assessment for ccRCC in the clinic. SIGNIFICANCE: These findings uncover molecular mechanisms underlying lipid accumulation in ccRCC, suggesting the AMPK-GATA3-ECHS1 pathway as a potential therapeutic target and prognostic biomarker.


Assuntos
Carcinoma de Células Renais/genética , Regulação Neoplásica da Expressão Gênica , Neoplasias Renais/genética , Lipogênese/genética , Transdução de Sinais/genética , Proteínas Quinases Ativadas por AMP/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Aminoácidos de Cadeia Ramificada/análise , Aminoácidos de Cadeia Ramificada/biossíntese , Animais , Carcinogênese/genética , Carcinoma de Células Renais/metabolismo , Carcinoma de Células Renais/mortalidade , Carcinoma de Células Renais/patologia , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células , Regulação para Baixo , Enoil-CoA Hidratase/metabolismo , Ácidos Graxos/análise , Ácidos Graxos/biossíntese , Feminino , Fator de Transcrição GATA3/metabolismo , Células HEK293 , Humanos , Rim/patologia , Rim/cirurgia , Neoplasias Renais/metabolismo , Neoplasias Renais/mortalidade , Neoplasias Renais/patologia , Masculino , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Camundongos Knockout , Pessoa de Meia-Idade , Nefrectomia , Prognóstico , Intervalo Livre de Progressão , Adulto Jovem
19.
Leukemia ; 34(5): 1305-1314, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-31776466

RESUMO

Recurrent oncogenic mutations of MyD88 have been identified in a variety of lymphoid malignancies. Gain-of-function mutations of MyD88 constitutively activate downstream NF-κB signaling pathways, resulting in increased cellular proliferation and survival. However, whether MyD88 activity can be aberrantly regulated in MyD88-wild-type lymphoid malignancies remains poorly understood. SPOP is an adaptor protein of CUL3-based E3 ubiquitin ligase complex and frequently mutated genes in prostate and endometrial cancers. In this study, we reveal that SPOP binds to and induces the nondegradative ubiquitination of MyD88 by recognizing an atypical SPOP-binding motif in MyD88. This modification blocks Myddosome assembly and downstream NF-κB activation. SPOP is mutated in a subset of lymphoid malignancies, including diffuse large B-cell lymphoma (DLBCL). Lymphoid malignancies-associated SPOP mutants exhibited impaired binding to MyD88 and suppression of NF-κB activation. The DLBCL-associated, SPOP-binding defective mutants of MyD88 escaped from SPOP-mediated ubiquitination, and their effect on NF-κB activation is stronger than that of wild-type MyD88. Moreover, SPOP suppresses DLBCL cell growth in vitro and tumor xenograft in vivo by inhibiting the MyD88/NF-κB signaling. Therefore, SPOP acts as a tumor suppressor in DLBCL. Mutations in the SPOP-MyD88 binding interface may disrupt the SPOP-MyD88 regulatory axis and promote aberrant MyD88/NF-κB activation and cell growth in DLCBL.


Assuntos
Linfoma Difuso de Grandes Células B/prevenção & controle , Fator 88 de Diferenciação Mieloide/antagonistas & inibidores , NF-kappa B/antagonistas & inibidores , Proteínas Nucleares/metabolismo , Proteínas Repressoras/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitinas/metabolismo , Apoptose , Proliferação de Células , Humanos , Linfoma Difuso de Grandes Células B/genética , Linfoma Difuso de Grandes Células B/metabolismo , Linfoma Difuso de Grandes Células B/patologia , Mutação , Proteínas Nucleares/genética , Proteínas Repressoras/genética , Células Tumorais Cultivadas , Ubiquitina-Proteína Ligases/genética , Ubiquitinação
20.
Biol Proced Online ; 21: 23, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31798349

RESUMO

Background: Lysine post-translational modifications are important regulators of protein function. Proteomic and biochemical approaches have resulted in identification of several lysine modifications, including acetylation, crotonylation, and succinylation. Here, we developed an approach for surveying amide-bonded lysine modifications in the proteome of human tissues/cells based on the observation that many lysine modifications are amide-bonded and that the Salmonella enterica deacetylase, CobB, is an amidase. Results: After the proteome of human tissues/cells was denatured and the non-covalently bonded metabolites were removed by acetone washes, and the amide-bonded modifiers were released by CobB and analyzed using liquid- and/or gas chromatography/mass spectrometry metabolomic analysis. This protocol, which required 3-4 days for completion, was used to qualitatively identify more than 40 documented and unreported lysine modifications from the human proteome and to quantitatively analyze dynamic changes in targeted amide-bonded lysine modifications. Conclusions: We developed a method that was capable of monitoring and quantifying amide-bonded lysine modifications in cells of different origins.

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