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1.
Medicine (Baltimore) ; 99(35): e21488, 2020 08 28.
Artículo en Inglés | MEDLINE | ID: mdl-32871870

RESUMEN

BACKGROUND: Celiac disease is an autoimmune enteropathy characterized by an aberrant immune response to ingested gluten in genetically predisposed individuals. Studies have pointed to a rising prevalence of celiac disease in recent decades. Changes in diet and use of medication that may impact the gut microbiome have been suggested as potential contributors. Exposure to proton pump inhibitors (PPIs) was recently found to be associated with an increased risk for subsequent diagnosis of celiac disease. We aimed to investigate potential mechanisms for this link by examining the relationship between PPI use and gluten-related immune responses in the context of changes in gut microbiome. METHODS: We performed a post hoc analysis of blood and fecal samples from a recent randomized trial in order to assess the potential association between PPI use and development of celiac disease serology in conjunction with alterations in gastrointestinal microbial composition. The study included 12 healthy participants who were administered a PPI (Omeprazole; 40 mg twice daily) for 4 or 8 weeks. RESULTS: The analysis did not reveal an overall significant change in levels of serologic markers of celiac disease for the study cohort in response to PPI treatment. However, one individual developed a marked increase in the celiac disease-specific autoantibody response to transglutaminase 2 in conjunction with enhanced immune reactivity to gluten during the trial. Genotyping revealed positivity for the celiac disease-associated HLA-DQ2 and -DQ8 alleles. Furthermore, the observed elevation in antibody responses was closely associated with a sharp increase in fecal abundance of bacteria of the order Actinomycetales. CONCLUSIONS: The results of this exploratory analysis support further investigation of molecular mechanisms involved in the contribution of PPIs to celiac disease risk through the potential enhancement of gluten immunopathology and changes in gut microbial population.


Asunto(s)
Enfermedad Celíaca/sangre , Enfermedad Celíaca/inducido químicamente , Microbioma Gastrointestinal/efectos de los fármacos , Omeprazol/efectos adversos , Inhibidores de la Bomba de Protones/efectos adversos , Actinomycetales/crecimiento & desarrollo , Adulto , Alelos , Enfermedad Celíaca/epidemiología , Enfermedad Celíaca/metabolismo , Heces/microbiología , Femenino , Proteínas de Unión al GTP/sangre , Proteínas de Unión al GTP/efectos de los fármacos , Tracto Gastrointestinal/efectos de los fármacos , Tracto Gastrointestinal/microbiología , Genotipo , Glútenes/efectos adversos , Glútenes/inmunología , Antígenos HLA-DQ/metabolismo , Humanos , Masculino , Persona de Mediana Edad , Omeprazol/administración & dosificación , Omeprazol/uso terapéutico , Prevalencia , Proteína Glutamina Gamma Glutamiltransferasa 2 , Inhibidores de la Bomba de Protones/administración & dosificación , Inhibidores de la Bomba de Protones/uso terapéutico , Transglutaminasas/sangre , Transglutaminasas/efectos de los fármacos
2.
Arch Toxicol ; 94(11): 3861-3875, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-32749514

RESUMEN

Organophosphate compounds (OPs) induce both acute and delayed neurotoxic effects, the latter of which is believed to involve their interaction with proteins other than acetylcholinesterase. However, few OP-binding proteins have been identified that may have a direct role in OP-induced delayed neurotoxicity. Given their ability to disrupt Ca2+ homeostasis, a key aim of the current work was to investigate the effects of sub-lethal neurite outgrowth inhibitory levels of OPs on the Ca2+-dependent enzyme tissue transglutaminase (TG2). At 1-10 µM, the OPs phenyl saligenin phosphate (PSP) and chlorpyrifos oxon (CPO) had no effect cell viability but induced concentration-dependent decreases in neurite outgrowth in differentiating N2a neuroblastoma cells. The activity of TG2 increased in cell lysates of differentiating cells exposed for 24 h to PSP and chlorpyrifos oxon CPO (10 µM), as determined by biotin-cadaverine incorporation assays. Exposure to both OPs (3 and/or 10 µM) also enhanced in situ incorporation of the membrane permeable substrate biotin-X-cadaverine, as indicated by Western blot analysis of treated cell lysates probed with ExtrAvidin peroxidase and fluorescence microscopy of cell monolayers incubated with FITC-streptavidin. Both OPs (10 µM) stimulated the activity of human and mouse recombinant TG2 and covalent labelling of TG2 with dansylamine-labelled PSP was demonstrated by fluorescence imaging following SDS-PAGE. A number of TG2 substrates were tentatively identified by mass spectrometry, including cytoskeletal proteins, chaperones and proteins involved protein synthesis and gene regulation. We propose that the elevated TG2 activity observed is due to the formation of a novel covalent adduct between TG2 and OPs.


Asunto(s)
Diferenciación Celular/efectos de los fármacos , Proteínas de Unión al GTP/efectos de los fármacos , Neuroblastoma/metabolismo , Proyección Neuronal/efectos de los fármacos , Organofosfatos/toxicidad , Transglutaminasas/efectos de los fármacos , Aminas/metabolismo , Animales , Biotina/análogos & derivados , Biotina/metabolismo , Línea Celular Tumoral , Supervivencia Celular , Cloropirifos/análogos & derivados , Cloropirifos/toxicidad , Humanos , Ratones , Compuestos Organofosforados/toxicidad , Proteína Glutamina Gamma Glutamiltransferasa 2 , Proteómica , Ratas , Especies Reactivas de Oxígeno
3.
Int J Mol Sci ; 21(7)2020 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-32260198

RESUMEN

In a recent report, no significance of transglutaminase 2 (TGase 2) was noted in the analyses of expression differences between normal and clear cell renal cell carcinoma (ccRCC), although we found that knock down of TGase 2 induced significant p53-mediated cell death in ccRCC. Generally, to find effective therapeutic targets, we need to identify targets that belong specifically to a cancer phenotype that can be differentiated from a normal phenotype. Here, we offer precise reasons why TGase 2 may be the first therapeutic target for ccRCC, according to several lines of evidence. TGase 2 is negatively regulated by von Hippel-Lindau tumor suppressor protein (pVHL) and positively regulated by hypoxia-inducible factor 1-α (HIF-1α in renal cell carcinoma (RCC). Therefore, most of ccRCC presents high level expression of TGase 2 because over 90% of ccRCC showed VHL inactivity through mutation and methylation. Cell death, angiogenesis and drug resistance were specifically regulated by TGase 2 through p53 depletion in ccRCC because over 90% of ccRCC express wild type p53, which is a cell death inducer as well as a HIF-1α suppressor. Although there have been no detailed studies of the physiological role of TGase 2 in multi-omics analyses of ccRCC, a life-long study of the physiological roles of TGase 2 led to the discovery of the first target as well as the first therapeutic treatment for ccRCC in the clinical field.


Asunto(s)
Antineoplásicos/farmacología , Carcinoma de Células Renales/genética , Proteínas de Unión al GTP/genética , Neoplasias Renales/genética , Transglutaminasas/genética , Antineoplásicos/uso terapéutico , Carcinoma de Células Renales/tratamiento farmacológico , Carcinoma de Células Renales/metabolismo , Resistencia a Antineoplásicos , Proteínas de Unión al GTP/efectos de los fármacos , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Humanos , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Neoplasias Renales/tratamiento farmacológico , Neoplasias Renales/metabolismo , Terapia Molecular Dirigida , Medicina de Precisión , Proteína Glutamina Gamma Glutamiltransferasa 2 , Transglutaminasas/efectos de los fármacos , Proteína p53 Supresora de Tumor/metabolismo , Proteína Supresora de Tumores del Síndrome de Von Hippel-Lindau/genética , Proteína Supresora de Tumores del Síndrome de Von Hippel-Lindau/metabolismo
4.
J Am Heart Assoc ; 5(7)2016 06 30.
Artículo en Inglés | MEDLINE | ID: mdl-27364991

RESUMEN

BACKGROUND: The pathogenesis of essential hypertension is multifactorial with different underlying mechanisms contributing to disease. We have recently shown that TNF superfamily member 14 LIGHT (an acronym for homologous to lymphotoxins, exhibits inducible expression, and competes with herpes simplex virus glycoprotein D for herpes virus entry mediator, a receptor expressed by T lymphocytes, also known as TNFSF14) induces hypertension when injected into mice. Research reported here was undertaken to examine the role of transglutaminase (TGase) in LIGHT-induced hypertension. METHODS AND RESULTS: Initial experiments showed that plasma and kidney TGase activity was induced by LIGHT infusion (13.91±2.92 versus 6.75±1.92 mU/mL and 19.86±3.55 versus 12.00±0.97 mU/10 µg) and was accompanied with hypertension (169±7.16 versus 117.17±11.57 mm Hg at day 14) and renal impairment (proteinuria, 61.33±23.21 versus 20.38±9.01 µg/mg; osmolality, 879.57±93.02 versus 1407.2±308.04 mmol/kg). The increase in renal TGase activity corresponded to an increase in RNA for the tissue TGase isoform, termed TG2. Pharmacologically, we showed that LIGHT-induced hypertension and renal impairment did not occur in the presence of cystamine, a well-known competitive inhibitor of TGase activity. Genetically, we showed that LIGHT-mediated induction of TGase, along with hypertension and renal impairment, was dependent on interleukin-6 and endothelial hypoxia inducible factor-1α. We also demonstrated that interleukin-6, endothelial hypoxia inducible factor-1α, and TGase are required for LIGHT-induced production of angiotensin receptor agonistic autoantibodies. CONCLUSIONS: Thus, LIGHT-induced hypertension, renal impairment, and production of angiotensin receptor agonistic autoantibodies require TGase, most likely the TG2 isoform. Our findings establish TGase as a critical link between inflammation, hypertension, and autoimmunity.


Asunto(s)
Presión Sanguínea/efectos de los fármacos , Hipertensión/inmunología , Inflamación/inmunología , Transglutaminasas/efectos de los fármacos , Miembro 14 de la Superfamilia de Ligandos de Factores de Necrosis Tumoral/farmacología , Animales , Autoanticuerpos/inmunología , Presión Sanguínea/inmunología , Proteínas de Unión al GTP/efectos de los fármacos , Proteínas de Unión al GTP/genética , Proteínas de Unión al GTP/metabolismo , Hipertensión/metabolismo , Subunidad alfa del Factor 1 Inducible por Hipoxia/genética , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Inflamación/metabolismo , Interleucina-6/genética , Interleucina-6/inmunología , Riñón/inmunología , Riñón/metabolismo , Ratones , Ratones Noqueados , Proteína Glutamina Gamma Glutamiltransferasa 2 , Proteinuria/inmunología , Proteinuria/metabolismo , Receptores de Angiotensina/inmunología , Insuficiencia Renal/inmunología , Insuficiencia Renal/metabolismo , Transglutaminasas/genética , Transglutaminasas/metabolismo
5.
Osteoarthritis Cartilage ; 23(10): 1743-54, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26045176

RESUMEN

OBJECTIVE: To describe gene expression in murine chondrocytes stimulated with IL-6 family cytokines and the impact of deleting Suppressor of Cytokine Signaling-3 (SOCS-3) in this cell type. METHOD: Primary chondrocytes were isolated from wild type and SOCS-3-deficient (Socs3(Δ/Δcol2)) mice and stimulated with oncostatin M (OSM), IL-6 plus the soluble IL-6 receptor (IL-6/sIL-6R), IL-11 or leukemia inhibitory factor (LIF) for 4 h. Total RNA was extracted and gene expression was evaluated by microarray analysis. Validation of the microarray results was performed using Taqman probes on RNA derived from chondrocytes stimulated for 1, 2, 4 or 8 h. Gene ontology was characterized using DAVID (database for annotation, visualization and integrated discovery). RESULTS: Multiple genes, including Bcl3, Junb, Tgm1, Angptl4 and Lrg1, were upregulated in chondrocytes stimulated with each gp130 cytokine. The gene transcription profile in response to OSM stimulation was pro-inflammatory and was highly correlated to IL-6/sIL-6R, rather than IL-11 or LIF. In the absence of SOCS-3, OSM and IL-6/sIL-6R stimulation induced an interferon (IFN)-like gene signature, including expression of IL-31ra and S100a9. CONCLUSION: While each gp130 cytokine induced a transcriptional response in chondrocytes, OSM- and IL-6/sIL-6R were the most potent members of this cytokine family. SOCS-3 plays an important regulatory role in this cell type, as it does in hematopoietic cells. Our results provide new insights into a hierarchy of gp130-induced transcriptional responses in chondrocytes that is normally restrained by SOCS-3 and suggest therapeutic inhibition of OSM may have benefit over and above antagonism of IL-6 during inflammatory arthritis.


Asunto(s)
Condrocitos/efectos de los fármacos , Regulación de la Expresión Génica/efectos de los fármacos , Inhibidores de Crecimiento/farmacología , Interleucina-11/farmacología , Interleucina-6/farmacología , Factor Inhibidor de Leucemia/farmacología , Oncostatina M/farmacología , ARN Mensajero/efectos de los fármacos , Proteínas Supresoras de la Señalización de Citocinas/genética , Proteína 4 Similar a la Angiopoyetina , Angiopoyetinas/genética , Animales , Proteínas del Linfoma 3 de Células B , Calgranulina B/efectos de los fármacos , Calgranulina B/genética , Cartílago Articular/citología , Condrocitos/metabolismo , Glicoproteínas/efectos de los fármacos , Glicoproteínas/genética , Inflamación/genética , Ratones , Ratones Noqueados , Proteínas Proto-Oncogénicas/efectos de los fármacos , Proteínas Proto-Oncogénicas/genética , ARN Mensajero/metabolismo , Receptores de Interleucina/efectos de los fármacos , Receptores de Interleucina/genética , Receptores de Interleucina-6 , Proteína 3 Supresora de la Señalización de Citocinas , Factores de Transcripción/efectos de los fármacos , Factores de Transcripción/genética , Transglutaminasas/efectos de los fármacos , Transglutaminasas/genética , Regulación hacia Arriba
6.
J Alzheimers Dis ; 42 Suppl 3: S289-303, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24685636

RESUMEN

Protein misfolding and the formation of stable insoluble protein complexes by self-interacting proteins, in particular amyloid-ß and tau protein, play a central role in the pathogenesis of Alzheimer's disease (AD). Unfortunately, the underlying mechanisms that trigger the misfolding of self-interacting proteins that eventually results in formation of neurotoxic dimers, oligomers, and aggregates remain unclear. Elucidation of the driving forces of protein complex formation in AD is of crucial importance for the development of disease-modifying therapies. Tissue transglutaminase (tTG) is a calcium-dependent enzyme that induces the formation of covalent ε-(γ-glutamyl)lysine isopeptide bonds, which results in both intra- and intermolecular protein cross-links. These tTG-catalyzed intermolecular cross-links induce stable, rigid, and insoluble protein complexes, whereas intramolecular cross-links change the conformation of proteins. Inhibition of tTG-catalyzed cross-linking counteracts the formation of protein aggregates, as observed in disease-models of other protein misfolding diseases, in particular Parkinson's and Huntington's diseases. Although data of tTG activity in AD models is limited, there is compelling evidence from both in vitro and postmortem human brain tissue of AD patients that point toward a crucial role for tTG in the pathogenesis of AD. Here, we review these data on the role of tTG in the initiation and development of protein aggregates in AD, and discuss the possibility to use inhibitors of the cross-linking activity of tTG as a new therapeutic approach for AD.


Asunto(s)
Enfermedad de Alzheimer/metabolismo , Enfermedad de Alzheimer/terapia , Proteínas de Unión al GTP/metabolismo , Transglutaminasas/metabolismo , Péptidos beta-Amiloides/metabolismo , Animales , Antipsicóticos/uso terapéutico , Proteínas de Unión al GTP/efectos de los fármacos , Humanos , Proteína Glutamina Gamma Glutamiltransferasa 2 , Transglutaminasas/efectos de los fármacos
7.
J Periodontol ; 84(10): 1469-75, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23173828

RESUMEN

BACKGROUND: Transglutaminase-2 (TGM-2) has been implicated in several fibrotic disorders and can be induced by reactive oxygen species (ROS). Hence, the authors hypothesize that cyclosporin A (CsA) may regulate TGM-2 via ROS, and this regulation may have a role in the pathogenesis of CsA-induced gingival overgrowth. METHODS: Cytotoxicity, 2',7'-dichlorodihydrofluorescein diacetate assay, and Western blot were used to investigate the effects of CsA in human gingival fibroblasts (HGFs). In addition, extracellular signal-regulated kinase (ERK) inhibitor PD98059, phosphatidylinositol 3-kinase inhibitor LY294002, glutathione precursor N-acetyl-L-cysteine (NAC), curcumin, epigallocatechin-3 gallate (EGCG), and p38 inhibitor SB203580 were added to find the possible regulatory mechanisms. RESULTS: Concentrations of CsA >500 ng/mL demonstrated cytotoxicity to HGFs (P < 0.05). CsA enhanced the generation of intracellular ROS at concentrations >200 ng/mL (P <0.05). TGM-2 protein induced by CsA was found in HGFs in a dose- and time-dependent manner (P <0.05). The addition of PD98059, LY294002, NAC, curcumin, EGCG, and SB203580 markedly inhibited TGM-2 expression induced by CsA (P <0.05). CONCLUSIONS: These results demonstrate that CsA significantly upregulates intracellular ROS generation and elevates TGM-2 expression in HGFs. In addition, TGM-2 induced by CsA is downregulated by PD98059, LY294002, NAC, curcumin, EGCG, and SB203580.


Asunto(s)
Ciclosporina/farmacología , Fibroblastos/efectos de los fármacos , Proteínas de Unión al GTP/efectos de los fármacos , Encía/efectos de los fármacos , Inmunosupresores/farmacología , Estrés Oxidativo/fisiología , Transglutaminasas/efectos de los fármacos , Acetilcisteína/farmacología , Adulto , Antioxidantes/farmacología , Catequina/análogos & derivados , Catequina/farmacología , Técnicas de Cultivo de Célula , Células Cultivadas , Cromonas , Curcumina/farmacología , Ciclosporina/toxicidad , Relación Dosis-Respuesta a Droga , Inhibidores Enzimáticos/farmacología , Quinasas MAP Reguladas por Señal Extracelular/antagonistas & inhibidores , Femenino , Flavonoides/farmacología , Depuradores de Radicales Libres/farmacología , Proteínas de Unión al GTP/antagonistas & inhibidores , Encía/citología , Humanos , Imidazoles/farmacología , Inmunosupresores/toxicidad , Masculino , Morfolinas , Inhibidores de las Quinasa Fosfoinosítidos-3 , Inhibidores de Proteasas/farmacología , Proteína Glutamina Gamma Glutamiltransferasa 2 , Piridinas/farmacología , Especies Reactivas de Oxígeno/metabolismo , Transglutaminasas/antagonistas & inhibidores , Regulación hacia Arriba/efectos de los fármacos
8.
Life Sci ; 92(2): 154-60, 2013 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-23201552

RESUMEN

AIMS: Alpinia katsumadai was recently found in our previous study to have anti-migratory and anti-invasion activities against HT-1080 cells. However, the study did not demonstrate the exact component of Alpinia katsumadai with anti-migratory and anti-invasive activities. We tested the effects and relevant mechanism of cardamonin (CDN) on the migration and invasion of cancer cells. MAIN METHODS: Migration and invasion of cancer cells were measured using multi-well chambers. Zymography and Western blots were used to examine the effects of CDN on the activities of matrix metalloproteinases (MMPs) and expression of transglutaminase-2 (Tgase-2). KEY FINDINGS: CDN, but not alpinetin, dose-dependently suppressed the migration and 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced invasion of HT-1080 sarcoma cells. CDN suppressed the expression of Tgase-2, MMP-2, NF-κB and MMP-9 in HT-1080 cells, and suppressed MMP-2 and MMP-9 activities. Gene silencing of Tgase-2 suppressed the migration and invasion of HT-1080 cells and suppressed the activities of MMP-2 and MMP-9. Migration of various cancer cells having high levels of Tgase-2 were also inhibited by CDN. CDN and Alpinia katsumadai extracts also directly inhibited the activity of Tgase-2. SIGNIFICANCE: CDN inhibits migration of several cancer cell lines expressing Tgase-2 via suppression of Tgase-2 expression and inhibition of Tgase-2 activity. The finding that CDN has Tgase-2 inhibitory activity will give us a new scaffold or clue of pharmacophore for the development of more effective Tgase-2 inhibitors.


Asunto(s)
Movimiento Celular/efectos de los fármacos , Chalconas/farmacología , Proteínas de Unión al GTP/efectos de los fármacos , Invasividad Neoplásica/fisiopatología , Transglutaminasas/efectos de los fármacos , Línea Celular Tumoral , Ensayos de Migración Celular , Movimiento Celular/fisiología , Relación Dosis-Respuesta a Droga , Proteínas de Unión al GTP/biosíntesis , Proteínas de Unión al GTP/fisiología , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Regulación Neoplásica de la Expresión Génica/fisiología , Silenciador del Gen/efectos de los fármacos , Silenciador del Gen/fisiología , Humanos , Metaloproteinasa 2 de la Matriz/biosíntesis , Metaloproteinasa 2 de la Matriz/efectos de los fármacos , Metaloproteinasa 2 de la Matriz/fisiología , Metaloproteinasa 9 de la Matriz/biosíntesis , Metaloproteinasa 9 de la Matriz/efectos de los fármacos , Metaloproteinasa 9 de la Matriz/fisiología , FN-kappa B/biosíntesis , FN-kappa B/efectos de los fármacos , FN-kappa B/fisiología , Invasividad Neoplásica/prevención & control , Proteína Glutamina Gamma Glutamiltransferasa 2 , Transglutaminasas/biosíntesis , Transglutaminasas/fisiología
9.
Dig Liver Dis ; 44(7): 555-62, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22381211

RESUMEN

BACKGROUND AND AIM: Searching for alternative therapies that are effective, safe and less expensive of those currently used for ulcerative colitis, we investigated the efficacy of a polyphenol extract from apple in rat colitis. METHODS: Rats with trinitrobenzensulphonic acid-induced colitis were treated daily with rectal administration of apple polyphenols 10(-4) M for 14 days. COX-2, TNF-α, tissue transglutaminase and calpain in colon mucosa samples were assessed by reverse transcription-polymerase chain reaction and western blot analyses. To ascertain the role of tissue transglutaminase in mucosal healing, wounded rat fibroblasts were incubated with cystamine (a tissue transglutaminase activity inhibitor). RESULTS: Colitis was associated with increased COX-2, TNF-α, calpain, and tissue transglutaminase mRNA. The protein expression of COX-2, TNF-α and calpain was increased whilst tissue transglutaminase was decreased. Apple extract treatment reduced the severity of colitis (p<0.05) and restored all the considered biomarkers at the baseline level. Apple polyphenols reduced the degradation of tissue transglutaminase protein occurring through calpain action. Apple polyphenols-treated wounded fibroblast recovered within 24h showing intense immunoreactivity for tissue transglutaminase. CONCLUSION: The efficacy of apple extract is mediated by its effects on COX-2 and TNF-α. The unbalance between calpain and tissue transglutaminase may play a role in colonic damage and future therapeutic interventions in ulcerative colitis can target this mechanisms.


Asunto(s)
Colitis/tratamiento farmacológico , Colitis/metabolismo , Mucosa Intestinal/metabolismo , Malus , Fitoterapia , Polifenoles/uso terapéutico , Animales , Calpaína/efectos de los fármacos , Calpaína/metabolismo , Colitis/inducido químicamente , Colitis/patología , Ciclooxigenasa 2/efectos de los fármacos , Ciclooxigenasa 2/metabolismo , Proteínas de Unión al GTP/efectos de los fármacos , Proteínas de Unión al GTP/metabolismo , Mucosa Intestinal/patología , Masculino , Ratones , Células 3T3 NIH , Extractos Vegetales/farmacología , Extractos Vegetales/uso terapéutico , Polifenoles/farmacología , Proteína Glutamina Gamma Glutamiltransferasa 2 , ARN Mensajero/metabolismo , Conejos , Ratas Wistar , Transglutaminasas/efectos de los fármacos , Transglutaminasas/metabolismo , Ácido Trinitrobencenosulfónico , Factor de Necrosis Tumoral alfa/efectos de los fármacos , Factor de Necrosis Tumoral alfa/metabolismo
10.
FEBS J ; 278(24): 4717-39, 2011 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-21902809

RESUMEN

Transglutaminase 2 (TG2) is the first described cellular member of an enzyme family catalyzing Ca(2+)-dependent transamidation of proteins. During the last two decades its additional enzymatic (GTP binding and hydrolysis, protein disulfide isomerase, protein kinase) and non-enzymatic (multiple interactions in protein scaffolds) activities, which do not require Ca(2+) , have been recognized. It became a prevailing view that TG2 is silent as a transamidase, except in extreme stress conditions, in the intracellular environment characterized by low Ca(2+) and high GTP concentrations. To counter this presumption a critical review of the experimental evidence supporting the role of this enzymatic activity in cellular processes is provided. It includes the structural basis of TG2 regulation through non-canonical Ca(2+) binding sites, mechanisms making it sensitive to low Ca(2+) concentrations, techniques developed for the detection of protein transamidation in cells and examples of basic cellular phenomena as well as pathological conditions influenced by this irreversible post-translational protein modification.


Asunto(s)
Calcio/metabolismo , Proteínas de Unión al GTP/metabolismo , Transglutaminasas/metabolismo , Envejecimiento/fisiología , Empalme Alternativo , Enfermedad de Alzheimer/fisiopatología , Secuencia de Aminoácidos , Animales , Sitios de Unión/genética , Reactivos de Enlaces Cruzados/metabolismo , Activación Enzimática , Espacio Extracelular/metabolismo , Proteínas de Unión al GTP/antagonistas & inhibidores , Proteínas de Unión al GTP/efectos de los fármacos , Guanosina Trifosfato/metabolismo , Humanos , Enfermedad de Huntington/fisiopatología , Datos de Secuencia Molecular , Oxidación-Reducción , Proteína Glutamina Gamma Glutamiltransferasa 2 , Procesamiento Proteico-Postraduccional , Alineación de Secuencia , Transglutaminasas/antagonistas & inhibidores , Transglutaminasas/efectos de los fármacos
11.
Tumori ; 95(2): 227-32, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19579870

RESUMEN

GOALS: Expression of GLUT-1 and transglutaminase 2 is increased in aggressive breast cancer, whereas claudin-1, which is expressed in normal tissues, is absent in such tumors. This experimental study was undertaken to establish the aggressiveness and prognosis of DMBA-induced mammary tumors in female Wistar rats based on the assessment of these markers. MATERIALS AND METHODS: The rats were divided into two groups, a control group (n = 70) and a chemoprevention group (n = 70). Breast tumors were induced in both groups by administration of 7,12-dimethylbenz[a] anthracene (DMBA). The chemoprevention group also received alpha-tocopherol and a solution of micronutrients containing ascorbic acid and selenium. Neoplastic lesions of both groups were randomly selected for immunohistochemical assessment of the expression of GLUT-1, transglutaminase 2 and claudin-1. RESULTS: A higher proportion of mammary tumors expressed GLUT-1 and transglutaminase 2 in the chemoprevention group. Claudin-1 expression was absent in all tumors of both groups. CONCLUSIONS: These results are suggestive of increased aggressiveness of tumors not susceptible to chemoprevention by the agents used in this study.


Asunto(s)
Anticarcinógenos/farmacología , Antioxidantes/farmacología , Biomarcadores de Tumor/metabolismo , Neoplasias de la Mama/enzimología , Neoplasias de la Mama/prevención & control , Proteínas de Unión al GTP/efectos de los fármacos , Transportador de Glucosa de Tipo 1/efectos de los fármacos , Transglutaminasas/efectos de los fármacos , 9,10-Dimetil-1,2-benzantraceno , Animales , Anticarcinógenos/administración & dosificación , Antioxidantes/administración & dosificación , Ácido Ascórbico/farmacología , Neoplasias de la Mama/inducido químicamente , Carcinógenos , Femenino , Regulación Enzimológica de la Expresión Génica/efectos de los fármacos , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Inmunohistoquímica , Proteína Glutamina Gamma Glutamiltransferasa 2 , Distribución Aleatoria , Ratas , Ratas Wistar , Compuestos de Selenio/farmacología , Insuficiencia del Tratamiento , alfa-Tocoferol/farmacología
12.
J Dent Res ; 88(2): 170-5, 2009 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-19278990

RESUMEN

Transglutaminase-2 (TGM-2) stabilizes extracellular matrix (ECM) proteins by cross-linking and has been implicated in several fibrotic disorders. Arecoline present in betel quid has been proposed as one of the causative factors for oral submucous fibrosis (OSMF). Hence, we hypothesize that arecoline may regulate TGM-2 and may have a role in the pathogenesis of OSMF. The expression of TGM-2 was studied in OSMF tissues by real-time RT-PCR analysis, and significant overexpression was observed in most OSMF tissues (P=0.0112) compared with normal tissues. Arecoline induced TGM-2 mRNA and protein expression as well as TGM-2 activity in human gingival fibroblast cells. The addition of methocramine hemihydrate (M-2 muscarinic acetylcholine receptor selective antagonist) or 8'-bromo-cAMP abolished arecoline-mediated TGM-2 induction, suggesting a role for M-2 muscarinic acid receptor and a repressor role for cAMP. Our study provides evidence for TGM-2 overexpression in OSMF and its regulation by arecoline in oral fibroblasts.


Asunto(s)
Arecolina/farmacología , Proteínas de Unión al GTP/efectos de los fármacos , Encía/enzimología , Fibrosis de la Submucosa Bucal/enzimología , Fibrosis de la Submucosa Bucal/etiología , Transglutaminasas/efectos de los fármacos , 8-Bromo Monofosfato de Adenosina Cíclica/farmacología , Western Blotting , Células Cultivadas , Inducción Enzimática/efectos de los fármacos , Proteínas de la Matriz Extracelular/metabolismo , Fibroblastos/enzimología , Proteínas de Unión al GTP/antagonistas & inhibidores , Proteínas de Unión al GTP/biosíntesis , Encía/citología , Humanos , Proteína Glutamina Gamma Glutamiltransferasa 2 , Receptor Muscarínico M2/antagonistas & inhibidores , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Transglutaminasas/antagonistas & inhibidores , Transglutaminasas/biosíntesis
13.
Toxicol In Vitro ; 22(6): 1511-9, 2008 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-18603402

RESUMEN

Mallory-Denk bodies (MDB) are hepatocyte inclusions containing cytokeratin 8 (CK8) which can develop, along with other steatohepatitis lesions, in patients treated with amiodarone, perhexiline maleate or 4,4'-diethylaminoethoxyhexestrol. These drugs accumulate lipids, whose subsequent peroxidation liberates reactive by-products, like malondialdehyde (MDA). The formation of MDB has been previously reproduced by 3,5-diethoxycarbonyl-1,4-dihydrocollidine or griseofulvin administration which cross-link CK8 by tissue transglutaminase, thus forming an entangled network, from which MDB progressively arise. The present study depicts the mechanisms initiating MDB formation by steatohepatitis-inducing drugs. Short incubation of hepatocytes with amiodarone (50 microM), 4,4'-diethylaminoethoxyhexestrol (50 microM) or perhexiline maleate (25 microM) increased the pool of CK8 monomers and increased cell calcium to activate Ca(++)-dependent transglutaminases which cross-linked the CK8 monomers into CK8-containing oligomers. The present study also provides the first evidence that MDA might directly participate in MDB formation, as this reactive agent cross-linked purified CK8 or albumin in vitro, disrupted the cytokeratin network of isolated hepatocytes, and bridged CK8 molecules. In conclusion, steatohepatitis-inducing drugs increase cell calcium and activate tissue transglutaminase, which cross-links CK8 to form a molecular scaffold, from which MDB might secondarily arise. Malondialdehyde also cross-links CK8, albeit through a different mechanism, and might also contribute to MDB formation.


Asunto(s)
Hepatocitos/efectos de los fármacos , Cuerpos de Inclusión/efectos de los fármacos , Queratina-8/efectos de los fármacos , Malondialdehído/metabolismo , Amiodarona/toxicidad , Animales , Calcio/metabolismo , Hígado Graso/inducido químicamente , Proteínas de Unión al GTP/efectos de los fármacos , Proteínas de Unión al GTP/metabolismo , Hepatocitos/metabolismo , Hexestrol/análogos & derivados , Hexestrol/toxicidad , Cuerpos de Inclusión/metabolismo , Queratina-8/metabolismo , Masculino , Perhexilina/análogos & derivados , Perhexilina/toxicidad , Proteína Glutamina Gamma Glutamiltransferasa 2 , Proteínas , Ratas , Ratas Sprague-Dawley , Transglutaminasas/efectos de los fármacos , Transglutaminasas/metabolismo
14.
Eur J Pharmacol ; 585(2-3): 464-72, 2008 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-18417122

RESUMEN

Alzheimer's disease, Parkinson's disease and Huntington's disease are neurodegenerative diseases, characterized by the accumulation and deposition of neurotoxic protein aggregates. The capacity of specific proteins to self-interact and form neurotoxic aggregates seems to be a common underlying mechanism leading to pathology in these neurodegenerative diseases. This process might be initiated and/or accelerated by proteins that interact with these aggregating proteins. The transglutaminase (TG) family of proteins are calcium-dependent enzymes that catalyze the formation of covalent epsilon-(gamma-glutamyl)lysine isopeptide bonds, which can result in both intra- and intermolecular cross-links. Intramolecular cross-links might modify self-interacting proteins, and make them more prone to aggregate. In addition, intermolecular cross-links could link self-aggregating proteins and thereby initiate and/or stimulate the aggregation process. So far, increased levels and activity of tissue transglutaminase (tTG), the best characterized member of the TG family, have been observed in many neurodegenerative diseases, and the self-interacting proteins, characteristic of Alzheimer's disease, Parkinson's disease and Huntington's disease, are known substrates of tTG. Here, we focus on the role of tTG in the initiation of the aggregation process of self-interacting proteins in these diseases, and promote the notion that tTG might be an attractive novel target for treatment of neurodegenerative diseases.


Asunto(s)
Proteínas del Tejido Nervioso/toxicidad , Enfermedades Neurodegenerativas/tratamiento farmacológico , Enfermedades Neurodegenerativas/enzimología , Transglutaminasas/efectos de los fármacos , Transglutaminasas/metabolismo , Enfermedad de Alzheimer/tratamiento farmacológico , Animales , Humanos , Enfermedad de Huntington/tratamiento farmacológico , Enfermedades Neurodegenerativas/genética , Fármacos Neuroprotectores/farmacología , Fármacos Neuroprotectores/uso terapéutico , Enfermedad de Parkinson/tratamiento farmacológico
15.
FASEB J ; 22(7): 2498-507, 2008 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-18353867

RESUMEN

Transglutaminase 2 (TGase2) is a ubiquitously expressed enzyme that catalyzes irreversible post-translational modification of protein, forming cross-linked protein aggregates. We previously reported that intracellular TGase2 is activated by oxidative stress. To elucidate the functional role of TGase2 activation in cells under the oxidatively stressed condition, we identified the mediator that activates TGase2. In this study, we showed that low levels of oxidative stress trigger the release of TGFbeta, which subsequently activates TGase2 through the nuclear translocation of Smad3. Analysis of substrate proteins reveals that TGase2-mediated protein modification results in a decrease of protein solubility and a collapse of intermediate filament network, which leads to aggregation of proteins. We confirm these results using lens tissues from TGase2-deficient mice. Among several antioxidants tried, only N-acetylcysteine effectively inhibits TGFbeta-mediated activation of TGase2. These results indicate that TGFbeta mediates oxidative stress-induced protein aggregation through activation of TGase2 and suggest that the formation of protein aggregation may not be a passive process of self-assembly of oxidatively damaged proteins but may be an active cellular response to oxidative stress. Therefore, TGFbeta-TGase2 pathway may have implications for both the pathogenesis of age-related degenerative diseases and the development of pharmaceutics.


Asunto(s)
Calcio/metabolismo , Proteínas de Unión al GTP/metabolismo , Estrés Oxidativo/fisiología , Factor de Crecimiento Transformador beta/farmacología , Transglutaminasas/metabolismo , Línea Celular , Activación Enzimática/efectos de los fármacos , Células Epiteliales/efectos de los fármacos , Células Epiteliales/enzimología , Proteínas de Unión al GTP/efectos de los fármacos , Humanos , Cristalino/efectos de los fármacos , Cristalino/enzimología , Estrés Oxidativo/efectos de los fármacos , Proteína Glutamina Gamma Glutamiltransferasa 2 , Transfección , Transglutaminasas/efectos de los fármacos
16.
Am J Pathol ; 167(1): 81-8, 2005 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-15972954

RESUMEN

Thrombospondin (TSP)-2-null dermal fibroblasts display an attachment defect that results from increased matrix metalloproteinase (MMP)-2 levels in their conditioned media. To investigate the molecular mechanisms responsible for this defect, we analyzed the activity of tissue transglutaminase (tTG) in TSP-2-null dermal fibroblasts and in tissues of TSP-2-null mice. tTG functions as a co-receptor for beta1 and beta3 integrins and stabilizes extracellular matrix proteins by introduction of isopeptide cross-links. Cell-surface tTG activity was reduced in TSP-2-null cells (0.50 +/- 0.05 arbitrary units versus 0.84 +/- 0.07 for wild type; P < or = 0.05), and addition of MMP-2 to the culture medium of wild-type cells caused a 35% reduction in cell-surface tTG activity. tTG was susceptible to proteolysis by MMP-2 in vitro, and addition of the MMP inhibitor TIMP-2 to TSP-2-null cells restored tTG activity (0.3 +/- 0.08 for untreated cells; 0.71 +/- 0.09 with TIMP-2). TSP-2-null mice had reduced tTG activity in skin, as measured by incorporation of fluorescein isothiocyanate-labeled cadaverine, and a threefold increase in acetic acid-extracted dermal collagen. Furthermore, isopeptide cross-links were reduced in both uninjured skin and in excisional wounds of TSP-2-null mice, as determined by morphometric immunohistochemical analysis, indicating that isopeptide cross-links are important for the stabilization of the collagenous matrix in dermis. These findings provide a mechanism for the reduced adhesion of TSP-2-null fibroblasts and an explanation for the increased collagen solubility and fragility of TSP-2-null skin.


Asunto(s)
Adhesión Celular/fisiología , Citoesqueleto/metabolismo , Fibroblastos/enzimología , Metaloproteinasa 2 de la Matriz/metabolismo , Transglutaminasas/metabolismo , Animales , Glicoproteínas de Membrana/efectos de los fármacos , Glicoproteínas de Membrana/metabolismo , Ratones , Ratones Transgénicos , Piel/enzimología , Trombospondinas/genética , Inhibidores Tisulares de Metaloproteinasas/farmacología , Transglutaminasas/efectos de los fármacos
17.
Mini Rev Med Chem ; 5(4): 367-79, 2005 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-15853627

RESUMEN

1,2,4-Thiadiazole is a distinctive class of small heterocyclic thiol trapping agents that serve as an interesting pharmacophore in the design of inhibitors targeting the cysteine residues of proteins. X-Ray crystal structures of enzyme-inhibitor complex indicate that the cysteine thiol reacts with the N-S bond of the thiadiazole moiety to form a disulfide bond resulting in the inactivation of the enzymes. This review addresses the medicinal chemistry and various properties of 1,2,4-thiadiazoles in their potential as new electrophilic "warheads" for targeting the cysteine residues of biomolecules (e.g, H+/K+ ATPase), and cysteine-dependent enzymes (e.g., cathepsin B and transglutaminase).


Asunto(s)
Inhibidores Enzimáticos/química , Inhibidores Enzimáticos/farmacología , Tiadiazoles/química , Tiadiazoles/farmacología , Catepsina B/química , Catepsina B/efectos de los fármacos , Cisteína/química , ATPasa Intercambiadora de Hidrógeno-Potásio/química , ATPasa Intercambiadora de Hidrógeno-Potásio/efectos de los fármacos , Transglutaminasas/química , Transglutaminasas/efectos de los fármacos
18.
Comp Biochem Physiol B Biochem Mol Biol ; 140(3): 395-402, 2005 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-15694587

RESUMEN

Scallop hemocytes contain a transglutaminase (TGase) that is electrophoretically different from the TGase in the adductor muscle. The optimum temperature of the hemocyte TGase was lower (about 15 degrees C), compared with the muscle TGase (35-40 degrees C). Other properties, such as the high sodium chloride (NaCl) and CaCl2 concentrations required for activation, instability in salt solutions, and the Km values against monodansylcadaverine (MDC) and succinylated casein, were similar for both enzymes. When hemocyte homogenate was incubated with MDC at 10 degrees C, MDC was incorporated into the 230 k and 100 k proteins of the hemocytes. The 100 k protein was only detected in the supernatant, the 230 k protein was insoluble, and the 210 k protein was detected in both fractions. In the absence of MDC, the 230 k, 210 k, and 100 k proteins were cross-linked by endogenous transglutaminase. The 230 k protein was most quickly cross-linked and formed huge polymers within 5 min. These results suggest that if scallop tissues are injured, hemocyte transglutaminase may be activated, initially cross-linking the insoluble hemocyte 230 k protein, followed by the 210 k and 100 k proteins, to form a cross-linked protein matrix with inter cross-linking of hemocyte sheets, to stop the bleeding.


Asunto(s)
Cadaverina/análogos & derivados , Hemocitos/enzimología , Moluscos/enzimología , Transglutaminasas/química , Animales , Cadaverina/metabolismo , Cadaverina/farmacología , Estabilidad de Enzimas , Hemolinfa/enzimología , Moluscos/citología , Sales (Química)/farmacología , Especificidad por Sustrato , Temperatura , Transglutaminasas/antagonistas & inhibidores , Transglutaminasas/efectos de los fármacos
19.
J Biochem Mol Biol ; 37(2): 185-91, 2004 Mar 31.
Artículo en Inglés | MEDLINE | ID: mdl-15469694

RESUMEN

Tissue transglutaminase (tTGase) regulates various biological processes, including extracellular matrix organization, cellular differentiation, and apoptosis. Here we report the protective role of tTGase in the cell death that is induced by the tumor necrosis factor alpha (TNF-alpha) and ceramide, a product of the TNF-alpha signaling pathway, in human neuroblastoma SH-SY5Y cells. Treatment with retinoic acid (RA) induced the differentiation of the neuroblastoma cells with the formation of extended neurites. Immunostaining and Western blot analysis showed the tTGase expression by RA treatment. TNF-alpha or C(2) ceramide, a cell permeable ceramide analog, induced cell death in normal cells, but cell death was largely inhibited by the RA treatment. The inhibition of tTGase by the tTGase inhibitors, monodansylcadaverine and cystamine, eliminated the protective role of RA-treatment in the cell death that is caused by TNF-alpha or C(2)-ceramide. In addition, the co-treatment of TNF-alpha and cycloheximide decreased the protein level of tTGase and cell viability in the RA-treated cells, supporting the role of tTGase in the protection of cell death. DNA fragmentation was also induced by the co-treatment of TNF-alpha and cycloheximide. These results suggest that tTGase expressed by RA treatment plays an important role in the protection of cell death caused by TNF-alpha and ceramide.


Asunto(s)
Apoptosis/efectos de los fármacos , Cadaverina/análogos & derivados , Neuroblastoma/metabolismo , Neuroblastoma/patología , Transglutaminasas/metabolismo , Factor de Necrosis Tumoral alfa/farmacología , Cadaverina/farmacología , Diferenciación Celular/efectos de los fármacos , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Ceramidas/farmacología , Cicloheximida/farmacología , Cistamina/farmacología , Citoprotección , Inhibidores Enzimáticos/farmacología , Humanos , Inmunohistoquímica , Neuronas/efectos de los fármacos , Neuronas/metabolismo , Neuronas/patología , Inhibidores de la Síntesis de la Proteína/farmacología , Transglutaminasas/antagonistas & inhibidores , Transglutaminasas/efectos de los fármacos , Tretinoina/farmacología
20.
Curr Drug Targets CNS Neurol Disord ; 3(2): 99-104, 2004 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-15078184

RESUMEN

Transglutaminases (TGases) belong to a family of closely related proteins that catalyze the cross linking of a glutaminyl residue of a protein/peptide substrate to a lysyl residue of a protein/peptide co-substrate with the formation of an Nepsilon-(gamma-L-glutamyl)-L-lysine [GGEL] cross link and the concomitant release of ammonia. Such cross-linked proteins are often highly insoluble. Neurodegenerative diseases, such as Alzheimer disease (AD), Parkinson disease (PD), supranuclear palsy and Huntington disease (HD), are characterized in part by aberrant cerebral TGase activity and by increased cross-linked proteins in affected brain. In support of the hypothesis that TGases contribute to neurodegenerative disease, a recent study shows that knocking out TGase 2 in HD-transgenic mice results in increased lifespan. Moreover, recent studies show that cystamine, an in vitro TGase inhibitor, prolongs the lives of HD-transgenic mice. However, these findings are not definitive proof of TGase involvement in HD neuropathology. In neurodegenerative diseases, the brain is under oxidative stress and cystamine can theoretically be converted to the potent antioxidant cysteamine in vivo. Cystamine is also a caspase 3 inhibitor. In addition to neurodegenerative diseases, aberrant TGase activity is associated with celiac disease. Interestingly, a subset of celiac patients develops neurological disorders. This review focuses on the strategies that have been recently employed in the design of TGase inhibitors, and on the possible therapeutic benefits of selective TGase inhibitors to patients with neurodegenerative disorders or to patients with celiac disease.


Asunto(s)
Encéfalo/enzimología , Inhibidores Enzimáticos/farmacología , Enfermedades Neurodegenerativas/enzimología , Procesamiento Proteico-Postraduccional/fisiología , Transglutaminasas/metabolismo , Animales , Enfermedad Celíaca/tratamiento farmacológico , Enfermedad Celíaca/enzimología , Enfermedad Celíaca/fisiopatología , Cistamina/farmacología , Cistamina/uso terapéutico , Inhibidores Enzimáticos/uso terapéutico , Humanos , Ratones , Ratones Transgénicos , Enfermedades Neurodegenerativas/tratamiento farmacológico , Enfermedades Neurodegenerativas/fisiopatología , Procesamiento Proteico-Postraduccional/efectos de los fármacos , Transglutaminasas/efectos de los fármacos
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