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1.
Cell ; 173(7): 1728-1741.e13, 2018 06 14.
Artigo em Inglês | MEDLINE | ID: mdl-29804833

RESUMO

The ketogenic diet (KD) is used to treat refractory epilepsy, but the mechanisms underlying its neuroprotective effects remain unclear. Here, we show that the gut microbiota is altered by the KD and required for protection against acute electrically induced seizures and spontaneous tonic-clonic seizures in two mouse models. Mice treated with antibiotics or reared germ free are resistant to KD-mediated seizure protection. Enrichment of, and gnotobiotic co-colonization with, KD-associated Akkermansia and Parabacteroides restores seizure protection. Moreover, transplantation of the KD gut microbiota and treatment with Akkermansia and Parabacteroides each confer seizure protection to mice fed a control diet. Alterations in colonic lumenal, serum, and hippocampal metabolomic profiles correlate with seizure protection, including reductions in systemic gamma-glutamylated amino acids and elevated hippocampal GABA/glutamate levels. Bacterial cross-feeding decreases gamma-glutamyltranspeptidase activity, and inhibiting gamma-glutamylation promotes seizure protection in vivo. Overall, this study reveals that the gut microbiota modulates host metabolism and seizure susceptibility in mice.


Assuntos
Dieta Cetogênica , Microbioma Gastrointestinal , Convulsões/dietoterapia , Animais , Antibacterianos/farmacologia , Bacteroides/efeitos dos fármacos , Bacteroides/genética , Bacteroides/isolamento & purificação , Modelos Animais de Doenças , Fezes/microbiologia , Microbioma Gastrointestinal/efeitos dos fármacos , Ácido Glutâmico/metabolismo , Hipocampo/metabolismo , Mucosa Intestinal/metabolismo , Canal de Potássio Kv1.1/deficiência , Canal de Potássio Kv1.1/genética , Metaboloma/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos C3H , Camundongos Knockout , Análise de Componente Principal , RNA Ribossômico 16S/genética , RNA Ribossômico 16S/metabolismo , Convulsões/patologia , Ácido gama-Aminobutírico/metabolismo , gama-Glutamiltransferase/metabolismo
2.
PLoS Genet ; 19(7): e1010834, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37418503

RESUMO

Sulfur is an indispensable element for bacterial proliferation. Prior studies demonstrated that the human pathogen Staphylococcus aureus utilizes glutathione (GSH) as a source of nutrient sulfur; however, mechanisms of GSH acquisition are not defined. Here, we identify a five-gene locus comprising a putative ABC-transporter and predicted γ-glutamyl transpeptidase (ggt) that promotes S. aureus proliferation in medium supplemented with either reduced or oxidized GSH (GSSG) as the sole source of nutrient sulfur. Based on these phenotypes, we name this transporter operon the glutathione import system (gisABCD). Ggt is encoded within the gisBCD operon, and we show that the enzyme is capable of liberating glutamate using either GSH or GSSG as substrates, demonstrating it is a bona fide γ-glutamyl transpeptidase. We also determine that Ggt is expressed in the cytoplasm, representing only the second example of cytoplasmic Ggt localization, the other being Neisseria meningitidis. Bioinformatic analyses revealed that Staphylococcus species closely related to S. aureus encode GisABCD-Ggt homologs. However, homologous systems were not detected in Staphylococcus epidermidis. Consequently, we establish that GisABCD-Ggt provides a competitive advantage for S. aureus over S. epidermidis in a GSH- and GSSG-dependent manner. Overall, this study describes the discovery of a nutrient sulfur acquisition system in S. aureus that targets GSSG in addition to GSH and promotes competition against other staphylococci commonly associated with the human microbiota.


Assuntos
Staphylococcus aureus , gama-Glutamiltransferase , Humanos , Staphylococcus aureus/genética , gama-Glutamiltransferase/genética , Dissulfeto de Glutationa , Glutationa/genética , Enxofre
3.
Hum Genomics ; 18(1): 71, 2024 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-38915066

RESUMO

OBJECTIVE: To investigate the association between liver enzymes and ovarian cancer (OC), and to validate their potential as biomarkers and their mechanisms in OC. Methods Genome-wide association studies for OC and levels of enzymes such as Alkaline phosphatase (ALP), Aspartate aminotransferase (AST), Alanine aminotransferase, and gamma-glutamyltransferase were analyzed. Univariate and multivariate Mendelian randomization (MR), complemented by the Steiger test, identified enzymes with a potential causal relationship to OC. Single-cell transcriptomics from the GSE130000 dataset pinpointed pivotal cellular clusters, enabling further examination of enzyme-encoding gene expression. Transcription factors (TFs) governing these genes were predicted to construct TF-mRNA networks. Additionally, liver enzyme levels were retrospectively analyzed in healthy individuals and OC patients, alongside the evaluation of correlations with cancer antigen 125 (CA125) and Human Epididymis Protein 4 (HE4). RESULTS: A total of 283 single nucleotide polymorphisms (SNPs) and 209 SNPs related to ALP and AST, respectively. Using the inverse-variance weighted method, univariate MR (UVMR) analysis revealed that ALP (P = 0.050, OR = 0.938) and AST (P = 0.017, OR = 0.906) were inversely associated with OC risk, suggesting their roles as protective factors. Multivariate MR (MVMR) confirmed the causal effect of ALP (P = 0.005, OR = 0.938) on OC without reverse causality. Key cellular clusters including T cells, ovarian cells, endothelial cells, macrophages, cancer-associated fibroblasts (CAFs), and epithelial cells were identified, with epithelial cells showing high expression of genes encoding AST and ALP. Notably, TFs such as TCE4 were implicated in the regulation of GOT2 and ALPL genes. OC patient samples exhibited decreased ALP levels in both blood and tumor tissues, with a negative correlation between ALP and CA125 levels observed. CONCLUSION: This study has established a causal link between AST and ALP with OC, identifying them as protective factors. The increased expression of the genes encoding these enzymes in epithelial cells provides a theoretical basis for developing novel disease markers and targeted therapies for OC.


Assuntos
Fosfatase Alcalina , Biomarcadores Tumorais , Estudo de Associação Genômica Ampla , Análise da Randomização Mendeliana , Neoplasias Ovarianas , Polimorfismo de Nucleotídeo Único , Análise de Célula Única , Humanos , Feminino , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/patologia , Polimorfismo de Nucleotídeo Único/genética , Análise de Célula Única/métodos , Fosfatase Alcalina/genética , Fosfatase Alcalina/sangue , Biomarcadores Tumorais/genética , Proteína 2 do Domínio Central WAP de Quatro Dissulfetos/genética , Proteína 2 do Domínio Central WAP de Quatro Dissulfetos/metabolismo , Aspartato Aminotransferases/genética , Aspartato Aminotransferases/sangue , Fígado/patologia , Fígado/metabolismo , Alanina Transaminase/sangue , Alanina Transaminase/genética , gama-Glutamiltransferase/genética , gama-Glutamiltransferase/sangue , Antígeno Ca-125/genética , Regulação Neoplásica da Expressão Gênica/genética , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Proteínas de Membrana/genética , Pessoa de Meia-Idade
4.
Nature ; 567(7747): 244-248, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30842656

RESUMO

Germinal centres are important sites for antibody diversification and affinity maturation, and are also a common origin of B cell malignancies. Despite being made up of motile cells, germinal centres are tightly confined within B cell follicles. The cues that promote this confinement are incompletely understood. P2RY8 is a Gα13-coupled receptor that mediates the inhibition of migration and regulates the growth of B cells in lymphoid tissues1,2. P2RY8 is frequently mutated in germinal-centre B cell-like diffuse large B cell lymphoma (GCB-DLBCL) and Burkitt lymphoma1,3-6, and the ligand for this receptor has not yet been identified. Here we perform a search for P2RY8 ligands and find P2RY8 bioactivity in bile and in culture supernatants of several mouse and human cell lines. Using a seven-step biochemical fractionation procedure and a drop-out mass spectrometry approach, we show that a previously undescribed biomolecule, S-geranylgeranyl-L-glutathione (GGG), is a potent P2RY8 ligand that is detectable in lymphoid tissues at the nanomolar level. GGG inhibited the chemokine-mediated migration of human germinal-centre B cells and T follicular helper cells, and antagonized the induction of phosphorylated AKT in germinal-centre B cells. We also found that the enzyme gamma-glutamyltransferase-5 (GGT5), which was highly expressed by follicular dendritic cells, metabolized GGG to a form that did not activate the receptor. Overexpression of GGT5 disrupted the ability of P2RY8 to promote B cell confinement to germinal centres, which indicates that GGT5 establishes a GGG gradient in lymphoid tissues. This work defines GGG as an intercellular signalling molecule that is involved in organizing and controlling germinal-centre responses. As the P2RY8 locus is modified in several other types of cancer in addition to GCB-DLBCL and Burkitt lymphoma, we speculate that GGG might have organizing and growth-regulatory roles in multiple human tissues.


Assuntos
Linfócitos B/metabolismo , Receptores Purinérgicos P2Y/metabolismo , Animais , Linfócitos B/citologia , Linfócitos B/imunologia , Linhagem Celular , Movimento Celular/efeitos dos fármacos , Quimiocinas/imunologia , Feminino , Centro Germinativo/citologia , Centro Germinativo/imunologia , Humanos , Ligantes , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Tonsila Palatina/citologia , Tonsila Palatina/imunologia , Fosforilação , Proteínas Proto-Oncogênicas c-akt/metabolismo , Receptores Purinérgicos P2Y/genética , Linfócitos T Auxiliares-Indutores/citologia , Linfócitos T Auxiliares-Indutores/imunologia , gama-Glutamiltransferase/metabolismo
5.
Proc Natl Acad Sci U S A ; 119(28): e2122840119, 2022 07 12.
Artigo em Inglês | MEDLINE | ID: mdl-35867762

RESUMO

Chromophobe (Ch) renal cell carcinoma (RCC) arises from the intercalated cell in the distal nephron. There are no proven treatments for metastatic ChRCC. A distinguishing characteristic of ChRCC is strikingly high levels of reduced (GSH) and oxidized (GSSG) glutathione. Here, we demonstrate that ChRCC-derived cells exhibit higher sensitivity to ferroptotic inducers compared with clear-cell RCC. ChRCC-derived cells are critically dependent on cystine via the cystine/glutamate antiporter xCT to maintain high levels of glutathione, making them sensitive to inhibitors of cystine uptake and cyst(e)inase. Gamma-glutamyl transferase 1 (GGT1), a key enzyme in glutathione homeostasis, is markedly suppressed in ChRCC relative to normal kidney. Importantly, GGT1 overexpression inhibits the proliferation of ChRCC cells in vitro and in vivo, suppresses cystine uptake, and decreases levels of GSH and GSSG. Collectively, these data identify ferroptosis as a metabolic vulnerability in ChRCC, providing a potential avenue for targeted therapy for these distinctive tumors.


Assuntos
Sistema y+ de Transporte de Aminoácidos , Carcinoma de Células Renais , Cistina , Ferroptose , Glutationa , Neoplasias Renais , Sistema y+ de Transporte de Aminoácidos/metabolismo , Transporte Biológico , Carcinoma de Células Renais/tratamento farmacológico , Carcinoma de Células Renais/metabolismo , Carcinoma de Células Renais/patologia , Cistina/metabolismo , Glutationa/metabolismo , Dissulfeto de Glutationa/deficiência , Humanos , Neoplasias Renais/tratamento farmacológico , Neoplasias Renais/metabolismo , Neoplasias Renais/patologia , Terapia de Alvo Molecular , gama-Glutamiltransferase/metabolismo
6.
Biochem Biophys Res Commun ; 714: 149977, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38663093

RESUMO

Malignant tumors are characterized by a hypoxic microenvironment, and metabolic reprogramming is necessary to ensure energy production and oxidative stress resistance. Although the microenvironmental properties of tumors vary under acute and chronic hypoxia, studies on chronic hypoxia-induced metabolic changes are limited. In the present study, we performed a comprehensive metabolic analysis in a chronic hypoxia model using colorectal cancer (CRC) organoids, and identified an amino acid supply system through the γ-glutamyl cycle, a glutathione recycling pathway. We analyzed the metabolic changes caused by hypoxia over time and observed that chronic hypoxia resulted in an increase in 5-oxoproline and a decrease in oxidized glutathione (GSSG) compared to acute hypoxia. These findings suggest that chronic hypoxia induces metabolic changes in the γ-glutamyl cycle. Moreover, inhibition of the γ-glutamyl cycle via γ-glutamyl cyclotransferase (GGCT) and γ-glutamyl transferase 1 (GGT1) knockdown significantly reversed chronic hypoxia-induced upregulation of 5-oxoproline and several amino acids. Notably, GGT1 knockdown downregulated the intracellular levels of γ-glutamyl amino acids. Conclusively, these results indicate that the γ-glutamyl cycle serves as an amino acid supply system in CRC under chronic hypoxia, which provides fresh insight into cancer metabolism under chronic hypoxia.


Assuntos
Aminoácidos , Neoplasias Colorretais , Organoides , gama-Glutamiltransferase , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Humanos , Organoides/metabolismo , Organoides/patologia , gama-Glutamiltransferase/metabolismo , Aminoácidos/metabolismo , Hipóxia Celular , Microambiente Tumoral , Glutationa/metabolismo , Hipóxia/metabolismo , Hipóxia Tumoral , gama-Glutamilciclotransferase/metabolismo , gama-Glutamilciclotransferase/genética
7.
Cancer Immunol Immunother ; 73(7): 131, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38748299

RESUMO

PURPOSE: The variable responses to immunotherapy observed in gastric cancer (GC) patients can be attributed to the intricate nature of the tumor microenvironment. Glutathione (GSH) metabolism significantly influences the initiation and progression of gastric cancer. Consequently, targeting GSH metabolism holds promise for improving the effectiveness of Immune checkpoints inhibitors (ICIs). METHODS: We investigated 16 genes related to GSH metabolism, sourced from the MSigDB database, using pan-cancer datasets from TCGA. The most representative prognosis-related gene was identified for further analysis. ScRNA-sequencing analysis was used to explore the tumor heterogeneity of GC, and the results were confirmed by  Multiplex immunohistochemistry (mIHC). RESULTS: Through DEGs, LASSO, univariate and multivariate Cox regression analyses, and survival analysis, we identified GGT5 as the hub gene in GSH metabolism with the potential to promote GC. Combining CIBERSORT, ssGSEA, and scRNA analysis, we constructed the immune architecture of GC. The subpopulations of T cells were isolated, revealing a strong association between GGT5 and memory CD8+ T cells. Furthermore, specimens from 10 GC patients receiving immunotherapy were collected. mIHC was used to assess the expression levels of GGT5 and memory CD8+ T cell markers. Our results established a positive correlation between GGT5 expression, the enrichment of memory CD8+ T cells, and a suboptimal response to immunotherapy. CONCLUSIONS: Our study identifies GGT5, a hub gene in GSH metabolism, as a potential therapeutic target for inhibiting the response to immunotherapy in GC patients. These findings offer new insights into strategies for optimizing immunotherapy of GC.


Assuntos
Linfócitos T CD8-Positivos , Glutationa , Imunoterapia , Neoplasias Gástricas , Microambiente Tumoral , gama-Glutamiltransferase , Feminino , Humanos , Masculino , Biomarcadores Tumorais/metabolismo , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , gama-Glutamiltransferase/metabolismo , Glutationa/metabolismo , Inibidores de Checkpoint Imunológico/uso terapêutico , Inibidores de Checkpoint Imunológico/farmacologia , Imunoterapia/métodos , Linfócitos do Interstício Tumoral/imunologia , Linfócitos do Interstício Tumoral/metabolismo , Prognóstico , Neoplasias Gástricas/imunologia , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/tratamento farmacológico , Neoplasias Gástricas/patologia , Microambiente Tumoral/imunologia
8.
Metab Eng ; 85: 26-34, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38802041

RESUMO

Integration of novel compounds into biological processes holds significant potential for modifying or expanding existing cellular functions. However, the cellular uptake of these compounds is often hindered by selectively permeable membranes. We present a novel bacterial transport system that has been rationally designed to address this challenge. Our approach utilizes a highly promiscuous sulfonate membrane transporter, which allows the passage of cargo molecules attached as amides to a sulfobutanoate transport vector molecule into the cytoplasm of the cell. These cargoes can then be unloaded from the sulfobutanoyl amides using an engineered variant of the enzyme γ-glutamyl transferase, which hydrolyzes the amide bond and releases the cargo molecule within the cell. Here, we provide evidence for the broad substrate specificity of both components of the system by evaluating a panel of structurally diverse sulfobutanoyl amides. Furthermore, we successfully implement the synthetic uptake system in vivo and showcase its functionality by importing an impermeant non-canonical amino acid.


Assuntos
Escherichia coli , Escherichia coli/metabolismo , Escherichia coli/genética , Proteínas de Membrana Transportadoras/metabolismo , Proteínas de Membrana Transportadoras/genética , Engenharia Metabólica , gama-Glutamiltransferase/metabolismo , gama-Glutamiltransferase/genética
9.
Hepatology ; 78(3): 863-877, 2023 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-36082508

RESUMO

BACKGROUND AND AIMS: The prevalence of NAFLD is increasing globally and on a path to becoming the most frequent cause of chronic liver disease. Strategies for the prevention and treatment of NAFLD are urgently needed. APPROACH AND RESULTS: A 6-month prospective, randomized, double-blind, placebo-controlled clinical trial was conducted to assess the efficacy of daily NRPT (commercially known as Basis, a combination of nicotinamide riboside and pterostilbene) supplementation in 111 adults with NAFLD. The study consisted of three arms: placebo, recommended daily dose of NRPT (NRPT 1×), and a double dose of NRPT (NRPT 2×). NRPT appeared safe and well tolerated. At the end of the study, no significant change was seen in the primary endpoint of hepatic fat fraction with respect to placebo. However, among prespecified secondary outcomes, a time-dependent decrease in the circulating levels of the liver enzymes alanine aminotransferase (ALT) and gamma-glutamyltransferase (GGT) was observed in the NRPT 1× group, and this decrease was significant with respect to placebo. Furthermore, a significant decrease in the circulating levels of the toxic lipid ceramide 14:0 was also observed in the NRPT 1× group versus placebo, and this decrease was associated with a decrease in ALT in individuals of this group. A dose-dependent effect was not observed with respect to ALT, GGT, or ceramide 14:0 in the NRPT 2× group. CONCLUSIONS: This study demonstrates that NRPT at the recommended dose is safe and may hold promise in lowering markers of hepatic inflammation in patients with NAFLD.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Adulto , Humanos , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Hepatopatia Gordurosa não Alcoólica/complicações , Estudos Prospectivos , gama-Glutamiltransferase , Inflamação/tratamento farmacológico , Inflamação/complicações , Método Duplo-Cego , Alanina Transaminase
10.
Clin Genet ; 106(3): 224-233, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38553872

RESUMO

Exome sequencing (ES) has identified biallelic kinesin family member 12 (KIF12) mutations as underlying neonatal cholestatic liver disease. We collected information on onset and progression of this entity. Among consecutively referred pediatric patients at our centers, diagnostic ES identified 4 patients with novel, biallelic KIF12 variants using the human GRCh38 reference sequence, as KIF12 remains incompletely annotated in the older reference sequence GRCh37. A review of these and of 21 reported patients with KIF12 variants found that presentation with elevated serum transaminase activity in the context of trivial respiratory infection, without clinical features of liver disease, was more common (n = 18) than manifest cholestatic disease progressing rapidly to liver transplantation (LT; n = 7). Onset of liver disease was at age <1 year in 15 patients; LT was more common in this group. Serum gamma-glutamyl transpeptidase activity (GGT) was elevated in all patients, and total bilirubin was elevated in 15 patients. Liver fibrosis or cirrhosis was present in 14 of 18 patients who were biopsied. The 16 different pathogenic variants and 11 different KIF12 genotypes found were not correlated with age of onset or progression to LT. Identification of biallelic pathogenic KIF12 variants distinguishes KIF12-related disease from other entities with elevated GGT.


Assuntos
Cinesinas , Hepatopatias , Mutação , gama-Glutamiltransferase , Humanos , Cinesinas/genética , gama-Glutamiltransferase/sangue , gama-Glutamiltransferase/genética , Masculino , Feminino , Hepatopatias/genética , Hepatopatias/patologia , Lactente , Sequenciamento do Exoma , Recém-Nascido , Predisposição Genética para Doença , Transplante de Fígado , Genótipo , Alelos , Pré-Escolar , Criança
11.
BMC Cancer ; 24(1): 617, 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38773511

RESUMO

BACKGROUND: Hepatocellular carcinoma (HCC) presents a significant threat to individuals and healthcare systems due to its high recurrence rate. Accurate prognostic models are essential for improving patient outcomes. Gamma-glutamyl transpeptidase (GGT) and prealbumin (PA) are biomarkers closely related to HCC. This study aimed to investigate the predictive value of the GGT to PA ratio (GPR) and to construct prognostic nomograms for HCC patients without microvascular invasion. METHODS: We retrospectively analyzed data from 355 HCC patients who underwent radical hepatectomy at Shengjing Hospital of China Medical University between December 2012 and January 2021. Patients were randomly assigned to a training cohort (n = 267) and a validation cohort (n = 88). The linearity of GPR was assessed using restricted cubic spline (RCS) analysis, and the optimal cut-off value was determined by X-tile. Kaplan-Meier survival curves and log-rank tests were used to investigate the associations between GPR and both progression-free survival (PFS) and overall survival (OS). Cox multivariate regression analysis identified independent risk factors, enabling the construction of nomograms. Time-dependent receiver operating characteristic (ROC) and calibration curves were used to evaluate the accuracy of the nomograms. Decision curve analysis (DCA) assessed the predictive value of the models. RESULTS: Patients were categorized into GPR-low and GPR-high groups based on a GPR value of 333.33. Significant differences in PFS and OS were observed between the two groups (both P < 0.001). Cox multivariate analysis identified GPR as an independent risk factor for both PFS (OR = 1.80, 95% CI: 1.24-2.60, P = 0.002) and OS (OR = 1.87, 95% CI: 1.07-3.26, P = 0.029). The nomograms demonstrated good predictive performance, with C-index values of 0.69 for PFS and 0.76 for OS. Time-dependent ROC curves and calibration curves revealed the accuracy of the models in both the training and validation cohorts, with DCA results indicating notable clinical value. CONCLUSIONS: GPR emerged as an independent risk factor for both OS and PFS in HCC patients without microvascular invasion. The nomograms based on GPR demonstrated relatively robust predictive efficiency for prognosis.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Nomogramas , Pré-Albumina , gama-Glutamiltransferase , Humanos , Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/mortalidade , Carcinoma Hepatocelular/sangue , Carcinoma Hepatocelular/cirurgia , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/mortalidade , Neoplasias Hepáticas/sangue , Neoplasias Hepáticas/cirurgia , Feminino , Masculino , Pessoa de Meia-Idade , gama-Glutamiltransferase/sangue , gama-Glutamiltransferase/metabolismo , Estudos Retrospectivos , Prognóstico , Pré-Albumina/análise , Pré-Albumina/metabolismo , Biomarcadores Tumorais/sangue , Biomarcadores Tumorais/metabolismo , Hepatectomia , Adulto , Idoso , Curva ROC , Invasividade Neoplásica , Estimativa de Kaplan-Meier , Microvasos/patologia , Valor Preditivo dos Testes
12.
Cell Commun Signal ; 22(1): 402, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-39148040

RESUMO

BACKGROUND: Helicobacter pylori (H. pylori) infection is critical in the development and occurrence of gastric cancer. H. pylori secretes gamma-glutamyl transferase (GGT), which affects energy metabolism and histone methylation in mesenchymal stem cells. However, its effect on human gastric epithelial cells remains unclear. This study aimed to investigate the effects of GGT on energy metabolism and histone methylation in gastric epithelial cells and determine its role in the development and progression of H. pylori-induced gastric cancer. METHODS: A GGT knockout H. pylori strain and mouse gastric cancer model were constructed, and alpha-ketoglutarate (α-KG) was added. The underlying mechanism was investigated using proteomics, immunohistochemistry, Western blotting, and other experimental assays. RESULTS: H. pylori can colonize the host's stomach and destroy the gastric epithelium. GGT secreted by H. pylori decreased the concentration of glutamine in the stomach and increased H3K9me3 and H3K27me3 expression, which promoted the proliferation and migration of gastric epithelial cells. Additionally, α-KG reversed this effect. GGT increased the tumorigenic ability of nude mice. GGT, secreted by H. pylori, promoted the expression of ribosomal protein L15 (RPL15), while GGT knockout and supplementation with α-KG and trimethylation inhibitors reduced RPL15 expression and Wnt signaling pathway expression. CONCLUSIONS: H. pylori secreted GGT decreased the expression of glutamine and α-KG in gastric epithelial cells, increased the expression of histones H3K9me3 and H3K27me3, and activated the Wnt signaling pathway through RPL15 expression, ultimately changing the biological characteristics of the gastric epithelium and promoting the occurrence of gastric cancer. Altered energy metabolism and histone hypermethylation are important factors involved in this process.


Assuntos
Metabolismo Energético , Células Epiteliais , Helicobacter pylori , Histonas , Neoplasias Gástricas , gama-Glutamiltransferase , Neoplasias Gástricas/microbiologia , Neoplasias Gástricas/patologia , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/genética , Animais , Histonas/metabolismo , Metilação , Células Epiteliais/metabolismo , Células Epiteliais/microbiologia , Células Epiteliais/patologia , gama-Glutamiltransferase/metabolismo , gama-Glutamiltransferase/genética , Camundongos , Humanos , Camundongos Nus , Mucosa Gástrica/metabolismo , Mucosa Gástrica/microbiologia , Mucosa Gástrica/patologia , Proliferação de Células , Infecções por Helicobacter/metabolismo , Infecções por Helicobacter/microbiologia , Infecções por Helicobacter/patologia , Infecções por Helicobacter/complicações , Ácidos Cetoglutáricos/metabolismo
13.
Liver Int ; 44(9): 2329-2340, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38828515

RESUMO

BACKGROUND AND AIMS: Porto-sinusoidal vascular disease (PSVD) is an under-recognized and under-diagnosed disease. The purpose of this study was to investigate the clinical features and prognosis of PSVD. METHODS: The patients who underwent liver biopsies were analyzed retrospectively. The clinical and pathological data were reviewed and screened according to the latest diagnostic criteria of PSVD. RESULTS: A total of 234 patients were diagnosed as PSVD, including 103 patients presented with portal hypertension (PH) and 131 patients without PH. At baseline, the alanine aminotransferase (ALT) and γ-glutamyl transpeptidase (GGT) levels were higher in the no-PH group. The liver stiffness increased in the PH group. In histological review, obliterative portal venopathy, sinusoidal dilatation and architectural disturbance were more common in the PH group, while portal tract abnormalities were more widely distributed in the no-PH group. After a median follow-up of 43.6 months, the survival rate of patients with baseline liver decompensation was 76.0%, and that of patients at a liver compensated stage in the PH group was 98.7%. First variceal bleeding occurred in 13.8% of patients with gastric-oesophageal varices. None of the patients in the no-PH group developed portal hypertension during follow-up. CONCLUSIONS: PSVD can manifest as PH or mild liver enzyme abnormalities. There are significant differences in pathological features among patients with different clinical manifestations. Recurrent ascites are the main cause of death in PSVD patients. However, patients without PH have a slow disease progression, with recurrent elevated GGT levels being their main clinical feature.


Assuntos
Varizes Esofágicas e Gástricas , Hipertensão Portal , Fígado , gama-Glutamiltransferase , Humanos , Hipertensão Portal/etiologia , Feminino , Masculino , Estudos Retrospectivos , Pessoa de Meia-Idade , China/epidemiologia , gama-Glutamiltransferase/sangue , Adulto , Varizes Esofágicas e Gástricas/etiologia , Fígado/patologia , Alanina Transaminase/sangue , Idoso , Veia Porta/patologia , Prognóstico , Hemorragia Gastrointestinal/etiologia , Biópsia
14.
World J Urol ; 42(1): 471, 2024 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-39110171

RESUMO

PURPOSE: Using ex vivo normothermic machine perfusion (NMP) with whole blood we assessed marginal porcine kidneys under reperfusion. The aim was to link measureable machine and clinical blood parameters with the currently used visual assessment. This could serve as a baseline for a standardized evaluation score to identify potentially transplantable kidneys in the future. METHODS: Kidneys and autologous whole blood were procured from slaughterhouse pigs (n = 33) and were perfused for 4 h using NMP. The hemodynamic parameters arterial pressure (AP), renal blood flow (RBF) and intrarenal resistance (IRR) were measured. Activity of aspartate transaminase (AST), gamma-glutamyltransferase (GGT), alkaline phosphatase (ALP), lactate dehydrogenase (LDH) and lactate were assessed in blood at 0/1/2/4 h. Kidneys were grouped into "potentially transplantable" (PT) or "not transplantable" (NT) based on their overall macroscopic appearance after NMP by an experienced physician. RESULTS: PT-kidneys (n = 20) had a significantly lower IRR and higher RBF than NT-kidneys (n = 13). GGT, ALP and LDH did not differ significantly, but at 4 h, AST was significantly higher in PT-kidneys compared to NT-kidneys. Lactate levels kept increasing during NMP in NT-kidneys and were significantly higher at 1/2/4 h than in PT-kidneys. CONCLUSION: The immediately assessed macroscopic aspects of examined kidneys correlated with hemodynamic parameters, increased lactate and lower AST in this study. In the future, NMP with whole blood could be a useful tool to extend the donor pool by allowing the assessment of otherwise unknown characteristics of marginal kidneys before transplantation.


Assuntos
Hemodinâmica , Transplante de Rim , Rim , Preservação de Órgãos , Perfusão , Animais , Suínos , Rim/fisiologia , Hemodinâmica/fisiologia , Preservação de Órgãos/métodos , Aspartato Aminotransferases/sangue , L-Lactato Desidrogenase/sangue , gama-Glutamiltransferase/sangue , Circulação Renal/fisiologia , Fosfatase Alcalina/sangue
15.
Diabetes Obes Metab ; 26(11): 4976-4988, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-39228281

RESUMO

AIM: Low birthweight is an issue during pregnancy associated with an increased risk of developing liver disease later in life. Previous Mendelian randomisation (MR) studies which explored this issue have not isolated the direct impact of the foetus on birthweight. In the present study, MR was used to assess whether direct foetal effects on birthweight were causally associated with liver structure, function and disease risk independent of intrauterine effects. MATERIALS AND METHODS: We extracted single nucleotide polymorphisms (SNPs) from genome-wide association studies (GWAS) about direct foetal-affected birthweight (321 223 cases) to conduct univariable and multivariable MR analyses to explore the relationships between birthweight and 4 liver structure measures, 9 liver function measures and 18 liver diseases. A two-step MR analysis was used to further assess and quantify the mediating effects of the mediators. RESULTS: When isolating direct foetal effects, genetically predicted lower birthweight was associated with a higher risk of non-alcoholic fatty liver disease (NAFLD) (odds ratios [OR], 95% confidence interval [CI]: 1.61, 1.29-2.02, p < 0.001), higher magnetic resonance imaging [MRI] proton density fat fraction (PDFF) and higher serum gamma glutamyltransferase (GGT). Two-step MR identified two candidate mediators that partially mediate the direct foetal effect of lower birthweight on NAFLD, including fasting insulin (proportion mediated: 22.29%) and triglycerides (6.50%). CONCLUSIONS: Our MR analysis reveals a direct causal association between lower birthweight and liver MRI PDFF, as well as the development of NAFLD, which persisted even after accounting for the potential influence of maternal factors. In addition, we identified fasting insulin and triglycerides as mediators linking birthweight and hepatic outcomes, providing insights for early clinical interventions.


Assuntos
Peso ao Nascer , Estudo de Associação Genômica Ampla , Fígado , Análise da Randomização Mendeliana , Hepatopatia Gordurosa não Alcoólica , Polimorfismo de Nucleotídeo Único , Humanos , Feminino , Gravidez , Fígado/patologia , Hepatopatia Gordurosa não Alcoólica/genética , Fatores de Risco , Imageamento por Ressonância Magnética , Recém-Nascido de Baixo Peso , Masculino , Recém-Nascido , gama-Glutamiltransferase/sangue
16.
BMC Gastroenterol ; 24(1): 109, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38491451

RESUMO

BACKGROUND: Metabolism dysfunction-associated fatty liver disease (MAFLD), is the most common chronic liver disease. Few MAFLD predictions are simple and accurate. We examined the predictive performance of the albumin-to-glutamyl transpeptidase ratio (AGTR), plasma atherogenicity index (AIP), and serum uric acid to high-density lipoprotein cholesterol ratio (UHR) for MAFLD to design practical, inexpensive, and reliable models. METHODS: The National Health and Nutrition Examination Survey (NHANES) 2007-2016 cycle dataset, which contained 12,654 participants, was filtered and randomly separated into internal validation and training sets. This study examined the relationships of the AGTR and AIP with MAFLD using binary multifactor logistic regression. We then created a MAFLD predictive model using the training dataset and validated the predictive model performance with the 2017-2018 NHANES and internal datasets. RESULTS: In the total population, the predictive ability (AUC) of the AIP, AGTR, UHR, and the combination of all three for MAFLD showed in the following order: 0.749, 0.773, 0.728 and 0.824. Further subgroup analysis showed that the AGTR (AUC1 = 0.796; AUC2 = 0.690) and the combination of the three measures (AUC1 = 0.863; AUC2 = 0.766) better predicted MAFLD in nondiabetic patients. Joint prediction outperformed the individual measures in predicting MAFLD in the subgroups. Additionally, the model better predicted female MAFLD. Adding waist circumference and or BMI to this model improves predictive performance. CONCLUSION: Our study showed that the AGTR, AIP, and UHR had strong MAFLD predictive value, and their combination can increase MAFLD predictive performance. They also performed better in females.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Ácido Úrico , Humanos , Feminino , Inquéritos Nutricionais , Albuminas , HDL-Colesterol , gama-Glutamiltransferase
17.
BMC Gastroenterol ; 24(1): 327, 2024 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-39350076

RESUMO

BACKGROUND: Microwave ablation (MWA) is widely used to eliminate colorectal liver metastases (CRLM). However, the risk of tumor recurrence is difficult to predict due to lack of reliable clinical and biological markers. Elevation of gamma-glutamyl transferase (GGT) and aspartate transaminase (AST) provides signals for liver inflammation and cancer progression. The present study evaluated the association between pre-ablation GGT to AST ratio index (GSR) and hepatic recurrence in patients with CRLM after MWA. METHODS: A retrospectively analyzed 192 CRLM patients who underwent MWA from January 2013 to December 2017. Pre-ablation GSR was classified into high (≤ 2.34) or low (> 2.34) using the upper quartile value. The prognostic value of GSR and other risk factors for liver progression-free survival (LPFS) and cancer-specific survival (CSS) were evaluated by univariate and multivariate analyses. RESULTS: High GSR was significantly associated with males (P = 0.041), the presence of cholelithiasis (P = 0.012), but not pre-ablation chemotherapy (P = 0.355), which caused significantly increased levels of GGT (P = 0.015) and AST (P = 0.008). GSR showed a significant association with LPFS and CSS through univariate analysis (P = 0.002 and 0.006) and multivariate analysis (P = 0.043 and 0.037). The subgroup analysis demonstrated no interaction between GSR and all variables except for distribution in the sub-analysis of LPFS. CONCLUSIONS: Our findings suggest that the pre-ablation GSR can be considered as a promising prognostic indicator for poor prognosis of patients with CRLM underwent MWA. TRIAL REGISTRATION: Not applicable.


Assuntos
Aspartato Aminotransferases , Neoplasias Colorretais , Neoplasias Hepáticas , Micro-Ondas , gama-Glutamiltransferase , Humanos , Masculino , Feminino , gama-Glutamiltransferase/sangue , Neoplasias Colorretais/patologia , Neoplasias Colorretais/sangue , Neoplasias Hepáticas/secundário , Neoplasias Hepáticas/sangue , Neoplasias Hepáticas/cirurgia , Neoplasias Hepáticas/mortalidade , Estudos Retrospectivos , Micro-Ondas/uso terapêutico , Pessoa de Meia-Idade , Aspartato Aminotransferases/sangue , Idoso , Prognóstico , Recidiva Local de Neoplasia/sangue , Biomarcadores Tumorais/sangue , Fatores de Risco , Adulto , Idoso de 80 Anos ou mais , Técnicas de Ablação
18.
BMC Gastroenterol ; 24(1): 183, 2024 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-38783185

RESUMO

OBJECTIVE: To evaluate the diagnostic accuracy of aspartate aminotransferase(AST)/ alanine transaminase (ALT), AST to platelet ratio index (APRI), fibrosis-4 score (FIB-4) and gamma-glutamyl transpeptidase to platelet count ratio (GPR) for hepatic fibrosis in patients with chronic hepatitis B (CHB). METHODS: A total of 1210 CHB patients who underwent liver biopsy were divided into two groups: patients with no significant fibrosis (control group) and patients with significant fibrosis, and routine laboratory tests were retrospectively included. Logistic regression models were used for the prediction, and the area under the receiver operating characteristic (AUROC) was used to assess the diagnostic accuracy. RESULTS: A total of 631 (52.1%) and 275 (22.7%) patients had significant fibrosis (≥ S2) and advanced fibrosis (≥ S3), respectively. The GPR showed significantly higher diagnostic accuracy than that of APRI, FiB-4, and AST/ALT to predict ≥ S2(significant fibrosis) and ≥ S3 fibrosis(advanced fibrosis), with an AUROC was 0.69 (95%CI: 0.66-0.71) and 0.72 (0.69-0.75), respectively. After stratified by the status of HBeAg ( positive or negative), GPR, APRI, and FiB-4 showed improved predicting performance for significant fibrosis and advanced fibrosis in HBeAg positive patients, with the most significant improvement was shown for GPR in predicting significant fibrosis (AUROC = 0.74, 95%CI: 0.70-0.78). CONCLUSIONS: Among the four noninvasive models, GPR has the best performance in the diagnosis of hepatic fibrosis in CHB patients and is more valuable in HBeAg-positive patients.


Assuntos
Alanina Transaminase , Aspartato Aminotransferases , Hepatite B Crônica , Cirrose Hepática , gama-Glutamiltransferase , Humanos , Hepatite B Crônica/complicações , Hepatite B Crônica/patologia , Hepatite B Crônica/sangue , Cirrose Hepática/sangue , Cirrose Hepática/patologia , Cirrose Hepática/diagnóstico , Masculino , Feminino , Contagem de Plaquetas , Aspartato Aminotransferases/sangue , Adulto , Alanina Transaminase/sangue , Estudos Retrospectivos , gama-Glutamiltransferase/sangue , Pessoa de Meia-Idade , Curva ROC , Biópsia , Fígado/patologia , Antígenos E da Hepatite B/sangue , Biomarcadores/sangue , Modelos Logísticos , Valor Preditivo dos Testes , Índice de Gravidade de Doença
19.
BMC Infect Dis ; 24(1): 638, 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38926648

RESUMO

BACKGROUND: This study aimed to evaluate the diagnostic abilities of the non-invasive serum biomarkers to predict liver fibrosis staging and evaluate the progress of hepatitis B. METHODS: We enrolled 433 patients with chronic HBV infection had complete medical data available for the study, who underwent percutaneous liver biopsy. The extent of fibrosis was assessed using the modified METAVIR score. The predictive values of the non-invasive serum biomarkers were evaluated by the areas under the receiving operator characteristics curves (AUROCs) with 95% confidence intervals. RESULTS: The proportion of males with progressive stages of liver fibrosis was relatively larger, and the average age of patients with cirrhosis stages is older than the non-cirrhotic stages. We found PLT, GGT, ALP, TB, FIB4 and GPR to be significantly associated with liver fibrosis in our cohort. GGT showed a sensitivity of 71.4% and specificity of 76.7% in distinguishing cirrhosis (F4) from non-cirrhotic stages (F1-3), with an AUROC of 0.775 (95%CI 0.711-0.840).The AUROCs of the GPR in distinguishing cirrhosis (F4) from non-cirrhotic stages (F1-3) was 0.794 (95%CI 0.734-0.853), but it had a lower sensitivity of 59.2%. Additionally, GGT, FIB4, and GPR could differentiate advanced fibrosis (F3-4) from non-advanced fibrosis (F1-2) among individuals with chronic hepatitis B, with AUROCs of 0.723 (95%CI 0.668-0.777), 0.729 (95%CI 0.675-0.782), and 0.760 (95%CI: 0.709-0.811) respectively. CONCLUSIONS: GGT was a better biomarker to distinguish cirrhosis (F4) from non-cirrhotic stages (F1-3), while GPR was a better biomarker to identify advanced fibrosis (F3-4) and non-advanced fibrosis (F1-2) in patients with chronic hepatitis B.


Assuntos
Biomarcadores , Hepatite B Crônica , Cirrose Hepática , Humanos , Masculino , Cirrose Hepática/sangue , Cirrose Hepática/diagnóstico , Cirrose Hepática/patologia , Hepatite B Crônica/sangue , Hepatite B Crônica/patologia , Hepatite B Crônica/complicações , Biomarcadores/sangue , Feminino , Pessoa de Meia-Idade , Adulto , Curva ROC , Progressão da Doença , Fígado/patologia , Sensibilidade e Especificidade , Índice de Gravidade de Doença , Biópsia , gama-Glutamiltransferase/sangue
20.
Eur J Nutr ; 63(1): 95-105, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37855891

RESUMO

PURPOSE: Recent evidence suggests that adherence to dietary approaches to stop hypertension (DASH) diet can be effective in managing non-alcoholic fatty liver disease (NAFLD). We investigated the effect of DASH diet on hepatic fibrosis, steatosis and liver enzymes in patients with NAFLD. METHODS: This 12-week randomized controlled trial was conducted among seventy patients with NAFLD who were randomly assigned into two groups including intervention group (DASH diet containing 50-55% carbohydrate, 15-20% protein, and 30% total fat) and the control group (a healthy diet containing 50-55% carbohydrate, 15-20% protein, and 30% total fat). Both diets were calorie-restricted (500-700 kcal lower than the energy requirement). The primary outcomes included hepatic fibrosis, hepatic steatosis, alanine transaminase (ALT), aspartate transaminase (AST) and gamma-glutamyl transpeptidase (GGT). RESULTS: At the baseline, there was no significant difference between two groups in the level of hepatic fibrosis (P = 0.63), hepatic steatosis (P = 0.53), ALT (P = 0.93), AST (P = 0.18) and GGT (P = 0.76). A significant reduction was found in the intervention group compared to the control group in hepatic fibrosis (23 grades reduction vs. 7 grades reduction; P = 0.008) and hepatic steatosis (31 grades reduction vs. 9 grades reduction; P = 0.03) after intervention. In addition, a significant change was observed in the intervention group compared to control group in ALT ( - 8.50 ± 8.98 vs. - 2.09 ± 7.29; P = 0.002), and AST ( - 5.79 ± 6.83 vs. - 0.51 ± 6.62; P = 0.002). CONCLUSIONS: Adherence to DASH diet may be effective in management of NAFLD. TRIAL REGISTRATION: The trial was registered on 06 February 2022 at Iranian Registry of Clinical Trials (IRCT20170117032026N3) with URL: https://www.irct.ir/trial/60887 .


Assuntos
Abordagens Dietéticas para Conter a Hipertensão , Hepatopatia Gordurosa não Alcoólica , Humanos , Irã (Geográfico) , Cirrose Hepática , Dieta , gama-Glutamiltransferase , Alanina Transaminase , Aspartato Aminotransferases , Fígado/patologia , Carboidratos
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