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1.
Sci Rep ; 11(1): 21514, 2021 11 02.
Artigo em Inglês | MEDLINE | ID: mdl-34728695

RESUMO

Coronavirus disease 2019 (COVID-19) is associated with systemic inflammation. A wide range of adipokines activities suggests they influence pathogenesis and infection course. The aim was to assess concentrations of chemerin, omentin, and vaspin among COVID-19 patients with an emphasis on adipokines relationship with COVID-19 severity, concomitant metabolic abnormalities and liver dysfunction. Serum chemerin, omentin and vaspin concentrations were measured in serum collected from 70 COVID-19 patients at the moment of admission to hospital, before any treatment was applied and 20 healthy controls. Serum chemerin and omentin concentrations were significantly decreased in COVID-19 patients compared to healthy volunteers (271.0 vs. 373.0 ng/ml; p < 0.001 and 482.1 vs. 814.3 ng/ml; p = 0.01, respectively). There were no correlations of analyzed adipokines with COVID-19 severity based on the presence of pneumonia, dyspnea, or necessity of Intensive Care Unit hospitalization (ICU). Liver test abnormalities did not influence adipokines levels. Elevated GGT activity was associated with ICU admission, presence of pneumonia and elevated concentrations of CRP, ferritin and interleukin 6. Chemerin and omentin depletion in COVID-19 patients suggests that this adipokines deficiency play influential role in disease pathogenesis. However, there was no relationship between lower adipokines level and frequency of COVID-19 symptoms as well as disease severity. The only predictive factor which could predispose to a more severe COVID-19 course, including the presence of pneumonia and ICU hospitalization, was GGT activity.


Assuntos
Adipocinas/sangue , Quimiocinas/sangue , Citocinas/sangue , Lectinas/sangue , Serpinas/sangue , Idoso , Índice de Massa Corporal , Proteína C-Reativa/análise , COVID-19/complicações , COVID-19/metabolismo , COVID-19/patologia , COVID-19/virologia , Estudos de Casos e Controles , Feminino , Proteínas Ligadas por GPI/sangue , Hospitalização , Humanos , Fígado/metabolismo , Masculino , Síndrome Metabólica/complicações , Pessoa de Meia-Idade , SARS-CoV-2/isolamento & purificação , gama-Glutamiltransferase/metabolismo
2.
Pol J Vet Sci ; 24(2): 225-233, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34250771

RESUMO

This study details the relationship between maternal plasma oxidant-antioxidant enzymes with colostrum quality, serum gamma glutamyl transferase (GGT), immunoglobulin G (IgG) and IgM concentrations of calves in the different calving seasons. Holstein breed cows between two and eight lactations and their calves were enrolled in the study. Holstein cows calving in winter (n=45) and their calves (n=45) were assigned to the winter group, while cows calving in summer (n=45) and their calves (n=45) were assigned to the summer group. Samples for malondialdehyde (MDA) and glutathione peroxidase (GSH-Px) were collected on day -21±3 before expected calving and also on calving day (Day 0). IgG and the specific gravity of the colostrum were determined after calving. Serum GGT and IgG and IgM were measured before the feeding, with colostrum, of calves (0 hours) and also in the 24th hour following the feeding of colostrum. Plasma MDA levels at -21±3 and 0 days in the summer cows were determined to be higher. GSH-Px activity was higher in the winter cows. IgG levels and the specific gravity of the colos- trum were also higher in the winter cows. Calf IgG levels at the 24th hour of life were higher in the winter cows. In the winter group, IgM levels at 0 and 24 hours were also higher. While MDA was negatively correlated with IgG, IgM, GGT, IgG and the specific gravity of colostrum, GSH-Px activity had a positive correlation with IgG, IgM, GGT, IgG and the specific gravity of colostrum. The observed differences in plasma MDA, GSH-Px, calf serum IgG and IgM levels, and colostrum quality between both groups suggest a possible seasonal effect. The relationship between maternal oxidant-antioxidant enzymes, colostrum quality, and passive calf immunity revealed that these enzymes could be used as indicators in the evaluation of calf health and colos- trum quality.


Assuntos
Antioxidantes/metabolismo , Bovinos/fisiologia , Colostro/fisiologia , Imunidade Materno-Adquirida/fisiologia , Estresse Oxidativo/fisiologia , Estações do Ano , Animais , Feminino , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Parto , Gravidez , gama-Glutamiltransferase/sangue , gama-Glutamiltransferase/metabolismo
3.
Theranostics ; 11(14): 7045-7056, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34093870

RESUMO

Rationale: Precise treatment of tumors is attracting increasing attention. Molecular probes simultaneously demonstrating the diagnostic signal and pharmacological effect in response to tumor microenvironment are highly desired. γ-glutamyl transpeptidase (GGT) is a biomarker with significantly up-regulated expression in the tumor area. We developed a GGT responsive near-infrared (NIR) nanoassembly for tumor-specific fluorescence imaging-guided photothermal therapy. Methods: The GGT responsive NIR probe was constructed by conjugating GGT-specific substrate γ-glutamic acid (γ-Glu) with cyanine fluorophore (NRh-NH2) via amide reaction. The resulting NRh-G spontaneously assembled into nanoparticles (NRh-G-NPs) around 50 nm. The NPs were characterized and the properties evaluated in the presence or absence of GGT. Subsequently, we studied fluorescence imaging and photothermal therapy of NRh-G-NPs in vitro and in vivo. Results: NRh-G-NPs, upon specific reaction with GGT, turned into NRh-NH2-NPs, showing a ~180-fold fluorescence enhancement and excellent photothermal effect recovery. NRh-G-NPs could selectively light up U87MG tumor cells while their fluorescence was weak in L02 human normal liver cells. The NPs also showed excellent tumor cell ablation upon laser irradiation. After intravenous injection into tumor-bearing mice, NRh-G-NPs could arrive in the tumor area and specifically light up the tumor. Following laser irradiation, the tumor could be completely erased with no tumor reoccurrence for up to 40 days. Conclusions: NRh-G-NPs were specifically responsive to GGT overexpressed in U87MG tumor cells and selectively lit up the tumor for imaging-guided therapy. Besides, the recovery of photothermal property in the tumor area could improve cancer therapy precision and decreased side effects in normal tissues.


Assuntos
Glioma/tratamento farmacológico , Glioma/radioterapia , Hipertermia Induzida/métodos , Nanopartículas/química , Terapia Fototérmica/métodos , Microambiente Tumoral/efeitos dos fármacos , Microambiente Tumoral/efeitos da radiação , gama-Glutamiltransferase/metabolismo , Animais , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos da radiação , Feminino , Fluorescência , Corantes Fluorescentes/química , Ácido Glutâmico/química , Humanos , Lasers , Camundongos , Camundongos Nus , Microscopia Eletrônica de Transmissão , Microscopia de Fluorescência , Nanopartículas/administração & dosagem , Nanopartículas/ultraestrutura , Espectroscopia de Luz Próxima ao Infravermelho , gama-Glutamiltransferase/genética
4.
Life Sci ; 278: 119572, 2021 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-33964294

RESUMO

AIM: Cisplatin is a potent chemotherapeutic agent whose therapeutic application is hindered by the associated nephrotoxicity. Cisplatin-evoked nephrotoxicity has been largely attributed to the induction of oxidative stress and inflammatory responses. The current study aimed at investigating the ability of ergothioneine to mitigate cisplatin-evoked nephrotoxicity and to elucidate the underlining molecular mechanisms. MAIN METHODS: Wistar rats were treated with a daily dose of ergothioneine (70 mg/kg, po) for fourteen days and a single dose of cisplatin (5 mg/kg, ip) on day ten. On day fifteen, kidneys and blood specimens were collected and subjected to Western blotting, ELISA, histopathological, and spectrophotometric analysis. KEY FINDINGS: Ergothioneine significantly enhanced renal function in cisplatin-treated rats as manifested by increased GFR and decreased serum creatinine and blood urea nitrogen. Ergothioneine effectively reduced the cisplatin-induced oxidative stress and mitigated apoptosis and the histopathological changes. Mechanistically, ergothioneine induced the expression of the antioxidant transcription factor Nrf2 and up-regulated its downstream targets NQO1 and HO-1. Equally important, ergothioneine inhibited γ-glutamyl transpeptidase that plays crucial roles in biotransformation of cisplatin into a toxic metabolite. Additionally, it reduced the pro-apoptotic protein p53 and the inflammatory transcription factor NF-κB along with its downstream pro-inflammatory cytokines TNF-α and IL-1ß. SIGNIFICANCE: The results of the current work shed the light on the ameliorating effect of ergothioneine on cisplatin-evoked nephrotoxicity that is potentially mediated through modulation of Nrf2, p53, and NF-κB signaling and inhibition of γ-glutamyl transpeptidase. This findings support the potential application of ergothioneine in controlling cisplatin-associated nephrotoxicity although clinical investigations are warranted.


Assuntos
Cisplatino/farmacologia , Ergotioneína/farmacologia , Rim/efeitos dos fármacos , Fator 2 Relacionado a NF-E2/metabolismo , NF-kappa B/metabolismo , gama-Glutamiltransferase/antagonistas & inibidores , Animais , Antineoplásicos/farmacologia , Antioxidantes/farmacologia , Apoptose , Caspase 3/metabolismo , Fragmentação do DNA , Masculino , Estresse Oxidativo , Ratos , Ratos Wistar , Transdução de Sinais , Proteína Supressora de Tumor p53/metabolismo , Regulação para Cima , gama-Glutamiltransferase/metabolismo
5.
Sci Rep ; 11(1): 10664, 2021 05 21.
Artigo em Inglês | MEDLINE | ID: mdl-34021168

RESUMO

Diagnosis of peritoneal metastasis in gastric cancer (GC) is essential for determining appropriate therapeutic strategies and avoiding non-essential laparotomy or gastrectomy. Recently, a variety of activatable fluorescence probes that can detect enzyme activities have been developed for cancer imaging. The aim of this study was to identify the key enzyme involved in peritoneal metastasis in GC. The enzymatic activity of gamma-glutamyl transpeptidase, dipeptidyl peptidase IV, and ß-galactosidase (ß-Gal) was assessed in lysates prepared from preserved human GC (n = 89) and normal peritoneal (NP; n = 20) samples. ß-Gal activity was significantly higher in the human GC samples than in NP samples, whereas no differences were observed in the activities of the other enzymes. Therefore, we used SPiDER-ßGal, a fluorescent probe that can be activated by ß-Gal, for imaging GC cell lines, peritoneal metastasis in a mouse model, and fresh human resected GC samples (n = 13). All cell lines showed fluorescence after applying SPiDER-ßGal, and metastatic nodules in the mice gradually developed high fluorescence that could be visualized with SPiDER-ßGal. The human GC samples showed significantly higher fluorescence than NP samples. ß-Gal is a useful target enzyme for fluorescence imaging of peritoneal metastasis in GC.


Assuntos
Biomarcadores Tumorais , Neoplasias Peritoneais/diagnóstico , Neoplasias Peritoneais/metabolismo , Neoplasias Peritoneais/secundário , Neoplasias Gástricas/patologia , beta-Galactosidase/metabolismo , Idoso , Idoso de 80 Anos ou mais , Linhagem Celular Tumoral , Ativação Enzimática , Feminino , Imunofluorescência , Humanos , Masculino , Imagem Óptica , Prognóstico , Curva ROC , gama-Glutamiltransferase/metabolismo
6.
J Am Chem Soc ; 143(15): 5674-5679, 2021 04 21.
Artigo em Inglês | MEDLINE | ID: mdl-33844539

RESUMO

Fluorogenic probes in the near-infrared (NIR) region have the potential to provide stimuli-dependent information in living organisms. Here, we describe a new class of fluorogenic probes based on the heptamethine cyanine scaffold, the most broadly used NIR chromophore. These compounds result from modification of heptamethine norcyanines with stimuli-responsive carbamate linkers. The resulting cyanine carbamates (CyBams) exhibit exceptional turn-ON ratios (∼170×) due to dual requirements for NIR emission: carbamate cleavage through 1,6-elimination and chromophore protonation. Illustrating their utility in complex in vivo settings, a γ-glutamate substituted CyBam was applied to imaging γ-glutamyl transpeptidase (GGT) activity in a metastatic model of ovarian cancer. Overall, CyBams have significant potential to extend the reach of fluorogenic strategies to intact tissue and live animal imaging applications.


Assuntos
Carbamatos/química , Carbocianinas/química , Corantes Fluorescentes/química , Animais , Linhagem Celular Tumoral , Modelos Animais de Doenças , Feminino , Transferência Ressonante de Energia de Fluorescência , Humanos , Camundongos , Microscopia Confocal , Metástase Neoplásica , Neoplasias Ovarianas/diagnóstico por imagem , Neoplasias Ovarianas/metabolismo , Espectroscopia de Luz Próxima ao Infravermelho , Transplante Heterólogo , gama-Glutamiltransferase/química , gama-Glutamiltransferase/metabolismo
7.
Am J Cardiol ; 149: 103-111, 2021 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-33762175

RESUMO

In non-ischemic dilated cardiomyopathy (DC) patients at risk of developing right heart failure (RHF), early depiction of congestive heart failure (CHF) is pivotal to inform about the hemodynamic status and tailor medical therapy. We hypothesized increased liver relaxation times measured at routine cardiovascular magnetic resonance (CMR), reflecting passive hepatic congestion, may be a valuable imaging biomarker to depict congestive heart failure. The study cohort consisted of DC patients with LV dysfunction (i.e., ejection fraction <35%) with (n = 48) and without (n = 46) right ventricular dysfunction (RVD), defined as a right ventricular ejection fraction <35%, and >45%, respectively, and a control group (n = 40). Native T1, T2, and extracellular volume (ECV) liver values were measured on routinely acquired cardiac maps. DC+RVD patients had higher C-reactive protein, troponin I and NT-pro BNP values, and worse LV functional parameters than DC-RVD patients (all p <0.001). T1, T2 and ECV Liver values were significantly higher in DC+RVD compared to DC-RVD patients and controls, that is, T1: 675 ± 88 ms verses 538 ± 39 ms and 540 ± 34 ms; T2: 54± 8 ms versus 45 ± 5 ms and 46 ± 4 ms; ECV: 36 ± 7% versus 29 ± 4% and 30 ± 3% (all p <0.001). Gamma-glutamyltranspeptidase (GGT) correlated moderately but significantly with native T1 (r2 = 0.34), T2 (r2 = 0.27), and ECV liver (r2 = 0.23) (all p <0.001). Using right atrial (RA) pressure, as surrogate measure of RHF (i.e., RA pressure >5 mm Hg), native T1 liver yielded at ROC analysis the highest area under the curve (0.906), significantly higher than ECV liver (0.813), GGT (0.806), T2 liver (0.797), total bilirubin (0.737) and alkaline phosphatase (0.561)(p = 0.04). A T1 value of 617 ms yielded a sensitivity of 79.5% and specificity of 91.0% to depict RHF. Excellent intra-/inter-observer agreement was found for assessment of native T1/T2/ECV liver values. In conclusion, in DC patients, assessment of liver relaxation times acquired on a cardiovascular magnetic resonance exam, may provide valuable information with regard to the presence of RHF.


Assuntos
Cardiomiopatia Dilatada/diagnóstico por imagem , Insuficiência Cardíaca/diagnóstico por imagem , Hiperemia/diagnóstico por imagem , Fígado/diagnóstico por imagem , Volume Sistólico , Disfunção Ventricular Esquerda/diagnóstico por imagem , Disfunção Ventricular Direita/diagnóstico , Adulto , Idoso , Fosfatase Alcalina/metabolismo , Pressão Atrial , Bilirrubina/metabolismo , Cardiomiopatia Dilatada/fisiopatologia , Estudos de Casos e Controles , Feminino , Insuficiência Cardíaca/fisiopatologia , Humanos , Hiperemia/fisiopatologia , Fígado/irrigação sanguínea , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Sensibilidade e Especificidade , Disfunção Ventricular Esquerda/fisiopatologia , Disfunção Ventricular Direita/metabolismo , Disfunção Ventricular Direita/fisiopatologia , gama-Glutamiltransferase/metabolismo
8.
Biosci Biotechnol Biochem ; 85(6): 1295-1313, 2021 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-33713104

RESUMO

The enzymatic characteristics of γ-glutamyltranspeptidase were elucidated. The catalytic nucleophile of the enzymatic reaction of Escherichia coli γ-glutamyltranspeptidase was identified as the Oγ of the N-terminal Thr-residue of the small subunit. It was demonstrated that the inactive precursor of γ-glutamyltranspeptidase is processed autocatalytically and intramolecularly into the active heterodimeric mature enzyme via an ester intermediate. The catalytic nucleophile of this processing reaction was identified as the same Oγ atom of the N-terminal Thr-residue of the small subunit. These results were also supported by the three-dimensional structures of the γ-glutamyl enzyme intermediate and of the precursor-mimicked T391A nonprocessable mutant enzyme. Applications of transpeptidation and hydrolysis activities of bacterial γ-glutamyltranspeptidases were developed. Using transpeptidation activity, efficient enzymatic production of useful γ-glutamyl compounds, such as prodrug for Parkinson's disease, theanine and kokumi compound, was enabled. Hydrolysis activity was used as glutaminase and the mutant enzymes gaining glutaryl-7-aminocephalosporanic acid acylase activity were isolated.


Assuntos
Glutamatos/metabolismo , gama-Glutamiltransferase/metabolismo , Biocatálise , Escherichia coli/enzimologia
9.
Int J Med Sci ; 18(8): 1899-1909, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33746607

RESUMO

The morbidity and mortality rates associated with non-small-cell lung carcinoma (NSCLC) are increasing every year, placing new demands on existing therapies and drugs. Ammonium ferric citrate (AFC) is often used as a food additive for iron supplementation; however, to our knowledge, no studies have investigated whether AFC can induce ferroptosis in NSCLC. In this study, we demonstrated that specific concentrations of AFC effectively inhibit the proliferation and invasion of lung cancer cell lines in vitro using a cell proliferation inhibition test, a transwell assay, and flow cytometry analysis of cell cycle and apoptosis. In addition, AFC significantly induced oxidative stress injury in lung cancer cell lines. A quantitative polymerase chain reaction assay showed that AFC markedly reduced the expression levels of cell growth factors, negative regulators of ferroptosis, and autophagy regulators. Lastly, a protein-protein interaction analysis revealed that glutathione peroxidase 4 (GPX4) exerted its biological role through the regulation of the GSS/GSR complex and downstream GGT family proteins. When the expression of GPX4 changes, its biological activities, such as the glutathione metabolic process, cellular biosynthetic process, cellular response to chemical stimulus, and antioxidant activity, change accordingly, thereby affecting the survival quality and physiological and biochemical activities of cells. Overall, this study verifies that AFC has the biological activity of activating oxidative stress injury in NSCLC cell lines, leading to a decrease in their autophagy and inducing ferroptosis. We also confirmed that the GPX4-GSS/GSR-GGT axis is a crucial target of AFC-induced ferroptosis.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Compostos Férricos/farmacologia , Ferroptose/efeitos dos fármacos , Neoplasias Pulmonares/tratamento farmacológico , Compostos de Amônio Quaternário/farmacologia , Carcinoma Pulmonar de Células não Pequenas/patologia , Linhagem Celular Tumoral , Ensaios de Seleção de Medicamentos Antitumorais , Compostos Férricos/uso terapêutico , Glutationa Redutase/metabolismo , Glutationa Sintase/metabolismo , Humanos , Neoplasias Pulmonares/patologia , Estresse Oxidativo/efeitos dos fármacos , Fosfolipídeo Hidroperóxido Glutationa Peroxidase/metabolismo , Compostos de Amônio Quaternário/uso terapêutico , Transdução de Sinais/efeitos dos fármacos , gama-Glutamiltransferase/metabolismo
10.
Eur J Med Chem ; 215: 113288, 2021 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-33640763

RESUMO

Kinesin spindle protein (KSP) is expressed only in cells undergoing cell division, and hence represents an attractive target for the treatment of cancer. Several KSP inhibitors have been developed and undergone clinical trial, but their clinical use is limited by their toxicity to rapidly proliferating non-cancerous cells. To create new KSP inhibitors that are highly selective for cancer cells, we optimized the amino acid moiety of S-trityl-l-cysteine (STLC) derivative 1 using in silico modeling. Molecular docking and molecular dynamics simulation were performed to investigate the binding mode of 1 with KSP. Consistent with the structure activity relationship studies, we found that a cysteine amino moiety plays an important role in stabilizing the interaction. Based on these findings and the structure of GSH, a substrate of γ-glutamyltransferase (GGT), we designed and synthesized the prodrug N-γ-glutamylated STLC derivative 9, which could be hydrolyzed by GGT to produce 1. The KSP ATPase inhibitory activity of 9 was lower than that of 1, and LC-MS analysis indicated that 9 was converted to 1 only in the presence of GGT in vitro. In addition, the cytotoxic activity of 9 was significantly attenuated in GGT-knockdown A549 cells. Since GGT is overexpressed on the cell membrane of various cancer cells, these results suggest that compound 9 could be a promising prodrug that selectively inhibits the proliferation of GGT-expressing cancer cells.


Assuntos
Antineoplásicos/farmacologia , Cisteína/farmacologia , Dibenzocicloeptenos/farmacologia , Cinesina/antagonistas & inibidores , Pró-Fármacos/farmacologia , Compostos de Tritil/farmacologia , Animais , Antineoplásicos/síntese química , Antineoplásicos/metabolismo , Bovinos , Linhagem Celular Tumoral , Cisteína/síntese química , Cisteína/metabolismo , Dibenzocicloeptenos/síntese química , Dibenzocicloeptenos/metabolismo , Humanos , Cinesina/metabolismo , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Estrutura Molecular , Pró-Fármacos/síntese química , Pró-Fármacos/metabolismo , Ligação Proteica , Relação Estrutura-Atividade , Termodinâmica , Compostos de Tritil/síntese química , Compostos de Tritil/metabolismo , gama-Glutamiltransferase/metabolismo
11.
Proc Natl Acad Sci U S A ; 118(8)2021 02 23.
Artigo em Inglês | MEDLINE | ID: mdl-33602816

RESUMO

Cell membrane-targeted bioimaging is a prerequisite for studying the roles of membrane-associated biomolecules in various physiological and pathological processes. However, long-term in situ bioimaging on the cell membrane with conventional fluorescent probes leads to diffusion into cells from the membrane surface. Therefore, we herein proposed a de novo strategy to construct an antidiffusion probe by integrating a fluorochrome characterized by strong hydrophobicity and low lipophilicity, with an enzyme substrate to meet this challenge. This precipitating fluorochrome HYPQ was designed by conjugating the traditionally strong hydrophobic solid-state fluorochrome 6-chloro-2-(2-hydroxyphenyl) quinazolin-4(3H)-one (HPQ) with a 2-(2-methyl-4H-chromen-4-ylidene) malononitrile group to obtain closer stacking to lower lipophilicity and elongate emission to the far-red to near-infrared wavelength. As proof-of-concept, the membrane-associated enzyme γ-glutamyltranspeptidase (GGT) was selected as a model enzyme to design the antidiffusion probe HYPQG. Then, benefiting from the precipitating and stable signal properties of HYPQ, in situ imaging of GGT on the membrane was successfully realized. Moreover, after HYPQG was activated by GGT, the fluorescence signal on the cell membrane remained unchanged, with incubation time even extending to 6 h, which is significant for in situ monitoring of enzymatic activity. In vivo testing subsequently showed that the tumor region could be accurately defined by this probe after long-term in situ imaging of tumor-bearing mice. The excellent performance of HYPQ indicates that it may be an ideal alternative for constructing universal antidiffusion fluorescent probes, potentially providing an efficient tool for accurate imaging-guided surgery in the future.


Assuntos
Membrana Celular , Corantes Fluorescentes/química , Imagem Molecular/métodos , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Animais , Linhagem Celular Tumoral , Membrana Celular/química , Membrana Celular/metabolismo , Difusão , Corantes Fluorescentes/síntese química , Corantes Fluorescentes/metabolismo , Células Hep G2 , Humanos , Camundongos , Células NIH 3T3 , Neoplasias Experimentais/diagnóstico por imagem , Estudo de Prova de Conceito , Quinazolinonas/química , Ensaios Antitumorais Modelo de Xenoenxerto , gama-Glutamiltransferase/análise , gama-Glutamiltransferase/metabolismo
12.
PLoS One ; 16(2): e0246131, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33544719

RESUMO

BACKGROUND: Gamma-glutamyl transferase (GGT) has recently been reported as a biomarker for cardiovascular (CVD) risk in general populations. We investigated the associations of GGT with cardio-metabolic diseases and CVD risk in South Africans living with HIV. METHODS: In this cross-sectional study, HIV-infected adults were randomly recruited across 17 HIV clinics in the Western Cape Province. Homeostatic model assessment for insulin resistance (HOMA-IR), hypertension, diabetes, metabolic syndrome by Joint Interim Statement criteria (JIS-MS), a ≥5% and ≥10% predicted risk for a CVD event within 10 years by the Framingham risk score (10-years-CVD risk) were computed. Associations between GGT and cardio-metabolic trait were explored using linear and binomial logistic regressions adjusted for age, gender, lifestyle behaviours and HIV-related characteristics. RESULTS: Among 709 participants (561 women, mean age 38.6 years), log-GGT was positively associated with waist circumference (ß=2.75; p<0.001), diastolic blood pressure (ß=1.65; p=0.006), total cholesterol (ß=0.21; p<0.001), low-density lipoprotein-cholesterol (ß=0.16; p<0.001), high-density lipoprotein-cholesterol and log-triglycerides (both ß=0.12; p<0.001), fasting plasma glucose (ß=0.19; p=0.031), 2-hour-post-glucose-load plasma glucose (ß=0.26; p=0.007), HOMA-IR (ß=0.13; p=0.001), log-high-sensitivity C-reactive-protein (ß=0.3; p<0.001) in linear regression analyses; with hypertension [OR=1.41 (95%CI, 1.13-1.75); p=0.001], JIS-MS [OR=1.33 (1.05-1.68); p=0.016], ≥5% 10-year-CVD risk [OR=1.55 (1.24-1.9400); p<0.001] and ≥10% 10-year-CVD risk [OR=1.56 (1.08-2.23); p=0.016] but not with diabetes [OR=1.24 (0.88-1.71), p=0.205] in logistic regression analyses. CONCLUSIONS: In this study, GGT levels were associated with cardio-metabolic variables independent of HIV specific attributes. If confirmed in longitudinal studies, GGT evaluation maybe included in CVD risk monitoring strategies in people living with HIV.


Assuntos
Proteína C-Reativa/metabolismo , Colesterol/sangue , Infecções por HIV/enzimologia , Síndrome Metabólica/diagnóstico , gama-Glutamiltransferase/metabolismo , Adulto , Pressão Sanguínea , Estudos Transversais , Feminino , Infecções por HIV/sangue , Humanos , Modelos Logísticos , Masculino , Síndrome Metabólica/sangue , Síndrome Metabólica/enzimologia , Pessoa de Meia-Idade , África do Sul , Circunferência da Cintura
13.
Hematology ; 26(1): 58-64, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33402059

RESUMO

OBJECTIVES: The remarkable effect of arsenic trioxide (ATO) was verified, but elevated gamma-glutamyltransferase (GGT), aminotransferases (ALT and AST) are generally observed in acute promyelocytic leukemia (APL) patients undergoing ATO treatment. However, utilization of hepatoprotective agents or discontinuation of ATO may inhibit ATO efficacy. In order to maintain ATO effect from hepatoprotective agents' influence so we investigate relationships between single elevation in GGT and hepatocellular injury in this study. METHODS: Correlation of GGT variation and leukocyte counts were analyzed in all 81 APL patients, correlations among liver enzymes (ALT, AST and GGT) were also analyzed in patients without prophylactic hepatoprotective agents. In following study, we take the clinical observation of changes in aminotransferases in patients with single elevation in GGT without hepatoprotective agents. RESULTS: The average elevated GGT in the WBC abnormal group was more than the normal group (53.86U/L vs. 31.03U/L, P = 0.008), a positive Pearson's correlation of GGT variation and changed leukocyte counts in patients without prophylactic hepatoprotective agents. There are no significant correlation between aminotransferases (ALT and AST) and GGT but correlation between ALT and AST was statistically significant (R = 0.649, P = 0.000). For APL patients with single elevation in GGT, ALT and AST levels were normal throughout the ATO treatment without hepatoprotective agents. CONCLUSION: Single elevation in GGT without elevated aminotransferases can't be identified as hepatotoxicity, and the elevated levels of GGT are associated with increasing leukocyte counts. Continue single-agent ATO without prophylactic hepatoprotective agents is recommended in APL patients with single elevation in GGT, in order to maintain ATO effect.


Assuntos
Antineoplásicos/uso terapêutico , Trióxido de Arsênio/uso terapêutico , Leucemia Promielocítica Aguda/tratamento farmacológico , gama-Glutamiltransferase/metabolismo , Adulto , Idoso , Antineoplásicos/efeitos adversos , Trióxido de Arsênio/efeitos adversos , Feminino , Humanos , Leucemia Promielocítica Aguda/metabolismo , Contagem de Leucócitos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Adulto Jovem
14.
Ann Nucl Med ; 35(2): 195-202, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33387280

RESUMO

OBJECTIVE: The variability of physiologic 18F-FDG uptake in the myocardium has hampered the accurate evaluation of cardiac glucose metabolism. We investigated the effects of multiple factors, including fasting duration and physical activity, on the physiologic uptake of 18F-FDG by the myocardium in healthy participants. METHODS: A total of 446 participants (predominantly male, 91%) in a health screening program were included in this retrospective study. For the visual analysis of myocardial 18F-FDG uptake, the participants were categorized into three groups according to qualitative visual scales (QVS). For the quantitative analysis, the maximum SUV of the left ventricular myocardium was measured. RESULTS: Significant differences were observed in fasting duration (p < 0.001), SUVmax (p < 0.001), aspartate aminotransferase (AST) (p < 0.001), alanine aminotransferase (ALT) (p < 0.001), gamma-glutamyl transpeptidase (γ-GTP) (p = 0.001), and uric acid (p = 0.015) among the QVS groups. Participants who regularly exercised with vigorous activity (p = 0.032) and HbA1c > 6% (p = 0.005) showed significant association with myocardial FDG uptake in the Chi-squared test. The median value of fasting duration decreased significantly as the QVS of the myocardium increased. Twenty-nine of the 31 participants (93.5%) who fasted for 21.5 h or more showed a suppressed FDG uptake (mean SUVmax = 2.1). In multivariate logistic regression analysis, fasting duration (OR = 0.74, 95% CI 0.69-0.80, p < 0.001), HbA1c > 6% (OR = 0.29, 95% CI: 0.12 - 0.66, p = 0.004), uric acid (OR = 0.82, 95% CI 0.68-1.00, p = 0.049) and regular exercise with vigorous activity (OR = 1.75, 95% CI 1.13-2.70, p = 0.012) were significant factors for physiologic myocardial FDG uptake. CONCLUSIONS: Reduced physiologic 18F-FDG uptake of the myocardium was associated with longer fasting duration, higher level of HbA1c, and less frequency of regular exercise with vigorous activity. For the preparation of cardiac 18F-FDG PET, inclusion of longer fasting duration (more than 18 h) might be necessary for the adequate suppression of physiologic 18F-FDG myocardial uptake.


Assuntos
Glicemia/metabolismo , Fluordesoxiglucose F18/farmacocinética , Hemoglobina A Glicada/metabolismo , Miocárdio/metabolismo , Compostos Radiofarmacêuticos/metabolismo , Adulto , Alanina Transaminase/metabolismo , Aspartato Aminotransferases/metabolismo , Exercício Físico , Ventrículos do Coração , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Pessoa de Meia-Idade , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Estudos Retrospectivos , Ácido Úrico/metabolismo , gama-Glutamiltransferase/metabolismo
15.
Angew Chem Int Ed Engl ; 60(4): 2125-2129, 2021 01 25.
Artigo em Inglês | MEDLINE | ID: mdl-33096584

RESUMO

γ-Glutamyltranspeptidase (GGT) is overexpressed in several types of cancer. Existing GGT-targeting fluorescence probes can image these cancers, but the fluorescent hydrolysis product leaks from the target cancer cells during prolonged incubation or fixation. Here, we present a functionalized fluorescence probe for GGT, 4-CH2 F-HMDiEtR-gGlu, which is designed to generate an azaquinone methide intermediate during activation by GGT; this intermediate reacts with intracellular nucleophiles to generate a fluorescent adduct that is trapped inside the cells, without loss of the target enzyme activity. Application of the probe to patient-derived xenograft (PDX) mice enabled in vivo cancer imaging for a prolonged period and was also compatible with fixation and immunostaining of the cancer tissue.


Assuntos
Corantes Fluorescentes/química , Neoplasias/diagnóstico por imagem , Imagem Óptica/métodos , gama-Glutamiltransferase/metabolismo , Animais , Xenoenxertos , Humanos , Camundongos , Espectrometria de Fluorescência/métodos
16.
Cancer Immunol Immunother ; 70(4): 1089-1099, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33113003

RESUMO

BACKGROUND: Hepatic immune-related adverse events (irAE) including elevated liver function tests (transaminases) occur in 1.4-22.3% of melanoma patients receiving immune checkpoint inhibitors (ICPI) and constitute a potentially serious toxicity that is challenging to treat. In contrast to the liver transaminases alanine aminotransferase (ALT) and aspartate aminotransferase (AST), only little is known about the frequency and impact of gamma-glutamyl transferase (GGT) elevations. METHODS: GGT determined prior to and during therapy of metastatic melanoma patients treated with ICPI were retrospectively assessed in two independent cohorts (PD-1: n = 218, Ipi + Nivo: n = 148). Overall survival (OS) and best objective response were analyzed according to baseline and immune-related GGT (irGGT) elevations during treatment. RESULTS: In multivariate analysis, OS was reduced in patients with elevated baseline GGT (PD-1 group: hazard ratio [HR] 1.76, p = .0073; Ipi + Nivo group: HR 1.77, p = .032). Immune-related GGT elevation was recorded in 17% (PD-1 group) and 38.5% (Ipi + Nivo group). Of these patients, the majority (81 and 68%, respectively) had normal ALT and AST and showed no clinical signs of hepatotoxicity. Patients who experienced irGGT elevation had superior response (PD-1 group: odds ratio [OR] 3.57, p = .00072; Ipi + Nivo group: OR 1.74, p = .12) and OS (PD-1 group: HR 0.37, p = .0016; Ipi + Nivo group: HR 0.33, p = .00050). CONCLUSIONS: The frequency of hepatic irAE is currently underestimated. The addition of the sensitive enzyme GGT to the laboratory panel before and during therapy with ICPI allows to detect two to three times more patients developing hepatic or hepatobiliary toxicity than known so far. Immune-related GGT elevations correlate with response and favorable survival. Precis for use in the Table of Contents The frequency of hepatotoxicity under immune checkpoint blockade is currently underestimated. We suggest the addition of gamma-glutamyl transferase to the laboratory panel in checkpoint inhibitor patients for the detection of hepatobiliary toxicity.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Biomarcadores Tumorais/metabolismo , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Melanoma/patologia , gama-Glutamiltransferase/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Seguimentos , Humanos , Ipilimumab/administração & dosagem , Masculino , Melanoma/tratamento farmacológico , Melanoma/enzimologia , Pessoa de Meia-Idade , Metástase Neoplásica , Nivolumabe/administração & dosagem , Prognóstico , Estudos Retrospectivos , Taxa de Sobrevida
17.
N Z Vet J ; 69(2): 104-112, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32981484

RESUMO

AIMS: To determine the gross and histological changes developing in the liver of sheep 8 months after a single period of exposure to sporidesmin and to examine associations between the severity of gross and histological changes to the liver and the activity of gamma-glutamyltransferase (GGT) measured in serum in the sheep at the time of intoxication. METHODS: A group of 50 Romney ewes grazing a mixed ryegrass/white clover pasture were accidentally exposed to sporidesmin for up to 5 weeks. Seventeen sheep showed photosensitisation and four were subject to euthanasia. The remaining sheep were moved to safer pasture and a blood sample collected and analysed for serum GGT activity. The sheep were slaughtered 8 months later. Livers were classified into grossly normal, moderately affected, or severely affected and histology performed to assess portal fibrosis, biliary hyperplasia, portal inflammation, and hepatocellular necrosis. RESULTS: Serum GGT activity ranged from 59 to 1571 IU/L (reference range 32-70 IU/L). Thirteen of the 46 sheep developed clinical signs of facial eczema. However, at slaughter all except four sheep had grossly detectable changes to the shape of the liver including atrophy of the left lobe and the lateral part of the right lobe. Hypertrophy was typically limited to the medial part of the right lobe. In severely affected sheep the liver hypertrophy formed a nodular bulging mass. Changes in the liver shape were classified as severe in 25 and moderate in 17 sheep. Severely affected livers contained significantly more fibrosis than moderately affected livers (p = 0.001, Cliff's delta (d) = 0.68). While there was significantly greater fibrosis and biliary hyperplasia in the left than right lobes, histological changes were present throughout all samples taken of affected livers. Serum GGT activity taken during acute intoxication were correlated to subsequent fibrosis and biliary hyperplasia. CONCLUSIONS: Hepatic fibrosis develops in sheep after a single episode of sporidesmin intoxication, even in sheep with only mildly elevated GGT activity at the time of intoxication. Furthermore, the severity of the subsequent hepatic fibrosis was predicted by the degree of elevation of serum GGT activity during intoxication. CLINICAL RELEVANCE: More research is required to determine how the presence and severity of hepatic fibrosis affect animal production. However, if hepatic fibrosis does decrease production, the consistent development of fibrosis after sporidesmin ingestion reinforces the importance of avoiding exposure of livestock to sporidesmin. ABBREVIATIONS: GGT: Gamma-glutamyltransferase; d: Cliff's delta.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas/veterinária , Eczema/veterinária , Face/patologia , Doenças dos Ovinos/induzido quimicamente , Esporidesminas/toxicidade , gama-Glutamiltransferase/metabolismo , Animais , Doença Hepática Induzida por Substâncias e Drogas/patologia , Doença Crônica , Eczema/induzido quimicamente , Eczema/patologia , Feminino , Fígado/patologia , Fármacos Fotossensibilizantes/toxicidade , Ovinos , Doenças dos Ovinos/patologia , gama-Glutamiltransferase/sangue
18.
J Hum Genet ; 66(2): 151-159, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32759993

RESUMO

Biallelic variants in the USP53 gene have recently been reported to segregate with normal gamma glutamyltransferase (GGT) cholestasis. Using whole-exome sequencing (WES), we detected two USP53 homozygous variants (c.951delT; p. Phe317fs and c.1744C>T; p. Arg582*) in five additional cases, including an unpublished cousin of a previously described family with intractable itching and normal GGT cholestasis. Three patients, a child and two adults, presented with recurrent episodes of normal GGT cholestasis, consistent with a diagnosis of benign recurrent intrahepatic cholestasis (BRIC). Cholangiopathic changes, possibly autoimmune in origin, were recognized in some patients. Additional phenotypic details in one patient included an enlarged left kidney, and speech/developmental delay. Notably, two patients exhibited a complete response to rifampicin, and one responded to ursodeoxycholic acid (UDCA). Two adult patients were suspected to have autoimmune liver disease and treated with steroids. This report describes new cases of USP53 disease presenting with normal GGT cholestasis or BRIC in three children and two adults. We also describe the novel finding of a dramatic response to rifampicin. The association of cholangiopathy with normal GGT cholestasis provides a diagnostic challenge and remains poorly understood.


Assuntos
Colangite/tratamento farmacológico , Colestase/tratamento farmacológico , Homozigoto , Mutação , Rifampina/farmacologia , Proteases Específicas de Ubiquitina/genética , gama-Glutamiltransferase/metabolismo , Adolescente , Adulto , Criança , Colangite/genética , Colangite/patologia , Colestase/genética , Colestase/patologia , Feminino , Humanos , Lactente , Masculino , Inibidores da Síntese de Ácido Nucleico/farmacologia , Linhagem , Prognóstico , Sequenciamento Completo do Exoma
19.
Hepatology ; 73(3): 937-951, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-32416645

RESUMO

BACKGROUND AND AIMS: Predictive, noninvasive tools are needed to monitor key features of nonalcoholic fatty liver disease (NAFLD) in children that relate to improvement in liver histology. The purpose of this study was to evaluate the relationship between liver chemistries and liver histology using data from the CyNCh (Cysteamine Bitartrate Delayed-Release for the Treatment of NAFLD in Children) clinical trial. APPROACH AND RESULTS: This study included 146 children. Improvement in liver histology, defined as decrease in nonalcoholic fatty liver disease (NAFLD) Activity Score ≥2 points without worsening of fibrosis, occurred in 43 participants (30%). There were 46 participants with borderline zone 1 nonalcoholic steatohepatitis (NASH) at baseline, with resolution in 28% (12 of 46). Multivariate models were constructed using baseline and change in alanine aminotransferase (ALT), aspartate aminotransferase (AST), and gamma-glutamyl transferase (GGT) at 52 weeks, for improvement in (1) liver histology primary outcome, (2) borderline zone 1 NASH, and (3) fibrosis. For improvement in histology, the model (P < 0.0001) retained baseline and change in GGT (area under the receiver operating characteristic [AUROC], 0.79; 95% confidence interval [CI], 0.71-0.87). For borderline zone 1 NASH, the model (P = 0.0004) retained baseline and change in ALT (AUROC, 0.80; 95% CI, 0.67-0.93). For fibrosis, the model (P < 0.001) retained baseline and change in ALT (AUROC, 0.80; 95% CI, 0.67-0.93). Additional clinical parameters were added to the models using Akaike's information criterion selection, and significantly boosted performance: improvement in histology with AUROC of 0.89 (95% CI, 0.82-0.95), borderline zone 1 NASH with AUROC of 0.91 (95% CI, 0.83-0.99), and fibrosis with AUROC of 0.89 (95% CI, 0.82-0.94). Models were validated using data from the TONIC (Treatment of Nonalcoholic Fatty Liver Disease in Children) trial. CONCLUSIONS: In children with NAFLD, dynamic changes in serum ALT and GGT are associated with change in liver histology and appear to be powerful indicators of histological response.


Assuntos
Alanina Transaminase/metabolismo , Fígado/patologia , Hepatopatia Gordurosa não Alcoólica/enzimologia , gama-Glutamiltransferase/metabolismo , Adolescente , Alanina Transaminase/sangue , Aspartato Aminotransferases/sangue , Aspartato Aminotransferases/metabolismo , Criança , Cisteamina/administração & dosagem , Cisteamina/uso terapêutico , Preparações de Ação Retardada , Feminino , Humanos , Masculino , Hepatopatia Gordurosa não Alcoólica/sangue , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Hepatopatia Gordurosa não Alcoólica/patologia , Valor Preditivo dos Testes , Prognóstico , Indução de Remissão , Resultado do Tratamento , gama-Glutamiltransferase/sangue
20.
Biochem Biophys Res Commun ; 534: 286-291, 2021 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-33288198

RESUMO

γ-Glutamyltranspeptidase (GGT) is a ubiquitous enzyme that catalyzes the hydrolysis of the γ-glutamyl linkage of γ-glutamyl compounds and the transfer of their γ-glutamyl moiety to acceptor substrates. Pseudomonas nitroreducens GGT (PnGGT) is used for the industrial synthesis of theanine, thus it is important to determine the structural basis of hydrolysis and transfer reactions and identify the acceptor site of PnGGT to improve the efficient of theanine synthesis. Our previous structural studies of PnGGT have revealed that crucial interactions between three amino acid residues, Trp385, Phe417, and Trp525, distinguish PnGGT from other GGTs. Here we report the role of Trp525 in PnGGT based on site-directed mutagenesis and structural analyses. Seven mutant variants of Trp525 were produced (W525F, W525V, W525A, W525G, W525S, W525D, and W525K), with substitution of Trp525 by nonaromatic residues resulting in dramatically reduced hydrolysis activity. All Trp525 mutants exhibited significantly increased transfer activity toward hydroxylamine with hardly any effect on acceptor substrate preference. The crystal structure of PnGGT in complex with the glutamine antagonist, 6-diazo-5-oxo-l-norleucine, revealed that Trp525 is a key residue limiting the movement of water molecules within the PnGGT active site.


Assuntos
Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Pseudomonas/enzimologia , Pseudomonas/genética , gama-Glutamiltransferase/química , gama-Glutamiltransferase/genética , Proteínas de Bactérias/metabolismo , Domínio Catalítico/genética , Cristalografia por Raios X , Modelos Moleculares , Mutagênese Sítio-Dirigida , Proteínas Mutantes/química , Proteínas Mutantes/genética , Proteínas Mutantes/metabolismo , Eletricidade Estática , Especificidade por Substrato , Triptofano/química , gama-Glutamiltransferase/metabolismo
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