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1.
Nutrients ; 16(13)2024 Jun 23.
Artículo en Inglés | MEDLINE | ID: mdl-38999741

RESUMEN

BN-202M is derived from humans and consists of two strains, Lacticaseibacillus paracasei BEPC22 and Lactiplantibacillus plantarum BELP53. Body fat reduction effect and safety of BN-202M were assessed in overweight participants. A total of 150 participants were randomly assigned to the BN-202M and placebo groups at a 1:1 ratio. Dual-energy X-ray absorptiometry was used to objectively measure body fat. After 12 weeks of oral administration, the body fat percentage (-0.10 ± 1.32% vs. 0.48 ± 1.10%; p = 0.009) and body fat mass (-0.24 ± 1.19 kg vs. 0.23 ± 1.05 kg; p = 0.023) of the BN-202M group decreased significantly compared to those of the placebo group. The body weight (-0.58 kg, p = 0.004) and body mass index (BMI; -0.23, p = 0.003) was found to decrease significantly at 12 weeks in the BN-202M group, but not in the placebo group. Metabolome analysis revealed that ß-alanine, 3-aminoisobutyric acid, glutamic acid, and octopamine decreased in the weight-decreased BN-202M post-intake group. In the gut microbiota analysis, Akkermansia showed a statistically significant increase in the BN-202M group post-intake compared to the placebo group. No serious adverse events were observed in either group. These results suggest that BN-202M is safe and effective for reducing body fat and weight.


Asunto(s)
Tejido Adiposo , Sobrepeso , Probióticos , Humanos , Masculino , Femenino , Método Doble Ciego , Probióticos/administración & dosificación , Adulto , Persona de Mediana Edad , Tejido Adiposo/metabolismo , Lacticaseibacillus paracasei , Índice de Masa Corporal , Lactobacillus plantarum , Absorciometría de Fotón
2.
Food Funct ; 15(2): 647-662, 2024 Jan 22.
Artículo en Inglés | MEDLINE | ID: mdl-38099933

RESUMEN

This study evaluated the effects of formulations with Lacticaseibacillus paracasei BEPC22 and Lactiplantibacillus plantarum BELP53 on adiposity, the alteration of microbiota, and the metabolome in high-fat diet-fed mice. The strains were selected based on their fat and glucose absorption inhibitory activities and potential metabolic interactions. The optimal ratio of the two strains in the probiotic formulation was determined based on their adipocyte differentiation inhibitory activities. Treatment of formulations with BEPC22 and BELP53 for 10 weeks decreased body weight gain at 6 weeks; it also decreased the food efficiency ratio, white adipose tissue volume, and adipocyte size. Moreover, it decreased the expression of the lipogenic gene Ppar-γ in the liver, while significantly increasing the expression of the fat oxidation gene Ppar-α in the white adipose tissue. Notably, treatment with a combination of the two strains significantly reduced the plasma levels of the obesity hormone leptin and altered the microbiota and metabolome. The omics data also indicated the alteration of anti-obesity microbes and metabolites such as Akkermansia and indolelactic acid, respectively. These findings suggest that treatment with a combination of BEPC22 and BELP53 exerts synergistic beneficial effects against obesity.


Asunto(s)
Microbioma Gastrointestinal , Lacticaseibacillus paracasei , Animales , Ratones , Dieta Alta en Grasa/efectos adversos , Receptores Activados del Proliferador del Peroxisoma/metabolismo , Obesidad/genética , Metaboloma , Ratones Endogámicos C57BL
3.
Oral Dis ; 2023 Sep 19.
Artículo en Inglés | MEDLINE | ID: mdl-37724481

RESUMEN

OBJECTIVE: This study investigated the effects of Lactobacillus fermentum BELF11 on periodontitis in mice (LIP). METHODS: Sixty mice were randomly assigned to a control group (CTL), LIP/PBS group (LIP and PBS applied), or LIP/BELF11 group (LIP and L. fermentum BELF11 applied). For 14 days, PBS or L. fermentum BELF11 was applied twice daily to the mice in the LIP/PBS or LIP/BELF11 group, respectively. After 14 days, radiographic, histological, and pro-inflammatory cytokine assessments were conducted. RESULTS: The LIP/PBS and LIP/BELF11 groups demonstrated greater alveolar bone loss than the CTL group (p < 0.05). The LIP/BELF11 group showed significantly reduced alveolar bone loss on the mesial side compared to the LIP/PBS group. Histologically, the LIP/BELF11 group showed consistent patterns of connective tissue fiber arrangement, lower levels of inflammatory infiltration, less alveolar bone loss, and higher alveolar bone density than the LIP/PBS group, despite showing more signs of destruction than the CTL group. The LIP/BELF11 group also exhibited significantly lower levels of pro-inflammatory cytokines than the LIP/PBS group. CONCLUSIONS: L. fermentum BELF11 inhibits alveolar bone loss and periodontitis progression by regulating pro-inflammatory cytokine production. These findings suggest that L. fermentum BELF11 may be a potential adjunctive therapy in periodontal treatment.

4.
Oncotarget ; 6(27): 24047-60, 2015 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-26090722

RESUMEN

The growth factors derived from the microenvironment create an environment conducive to tumor growth and survival. HGF deprivation using neutralizing antibody enhanced chemosensitivity in colorectal cancer cells (CRC). We determined secreted HGF in fibroblast conditioned medium (CM). Combination treatment of anti-HGF antibody and irinotecan (CPT-11) directly enhanced CPT-11 sensitivity in CRC. We generated xenograft in NOD/SCID mice inoculating HCT-116 human colorectal cancer cells subcutaneously with or without fibroblast. We found that the combination of CPT-11 and anti-HGF antibody induced marked suppression of tumor development. These results suggest that HGF produced by fibroblast induce CPT-11 resistance, and that anti-HGF antibody abrogate such resistance in vivo. fibroblast-derived HGF is important determinant of chemoresistance. Anti-HGF monoclonal antibody treatment confirmed the importance of this growth factor for chemoresistance in CRC. These results present new options toward the early diagnosis of chemoresistance and suggest novel combinations of chemotherapy and anti-HGF agents to prevent or significantly delay the onset of therapy resistance.


Asunto(s)
Anticuerpos Monoclonales/farmacología , Camptotecina/análogos & derivados , Neoplasias Colorrectales/tratamiento farmacológico , Resistencia a Antineoplásicos/efectos de los fármacos , Factor de Crecimiento de Hepatocito/inmunología , Animales , Anticuerpos Monoclonales/inmunología , Apoptosis/fisiología , Camptotecina/farmacología , Línea Celular Tumoral , Proliferación Celular , Medios de Cultivo Condicionados/farmacología , Activación Enzimática , Fibroblastos/metabolismo , Células HCT116 , Células HT29 , Humanos , Irinotecán , Neoplasias Pulmonares/tratamiento farmacológico , Ratones , Ratones Endogámicos NOD , Ratones SCID , Proteínas Proto-Oncogénicas c-met/metabolismo
5.
J Cancer Res Clin Oncol ; 136(1): 47-53, 2010 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-19572147

RESUMEN

PURPOSE: GPR56 is an orphan G-protein-coupled receptor of the adhesion family involved in brain development. In some cancer cells and tissues, GPR56 is highly expressed and may contribute to tumorigenesis phenotypes such as cell adhesion and metastasis. Although the ligand for GPR56 is unknown, the overexpression of the receptor induces the activity of several transcription factors. We identified Wve splicing forms of GPR56 by searching the genome database. In this study, we tried to assess the properties of the splicing variants on the activation of the transcription factors. METHODS: Genome structure of human GPR56 genes was analyzed using the Ensembl genome browser. All splicing variants were constructed using PCR with the GPR56 wildtype gene as template and the appropriate primers and their expression was verified by western blotting. We examined the effect of GPR56 splicing forms on the cellular responses through reporter gene assay with various promoters. We also confirmed the GPR56-mediated transcriptional activity by silencing GPR56 expression through shRNA-mediated RNA interference. RESULTS: We found that the coding sequence of GPR56 consist of 13 exons and alternative splicing occurs in the second and tenth exons. In reporter gene assays, GPR56 overexpression increased the activity of the serum-response element, NFAT, and E2F response elements, whereas this overexpression downregulated c-myc and p53 response element activity. Furthermore, increased promoter activity of the COX2, iNOS, and VEGF genes was observed. Variants 1 and 2 potently enhanced SRE-mediated transcription compared with wild-type GPR56. Variants 3 and 4 hardly aVect the activity of the promoters. CONCLUSION: These results suggested that the splicing of GPR56 may induce differential tumorigenic responses owing to their varied ability to activate transcription factors.


Asunto(s)
Empalme Alternativo , Neoplasias/genética , Receptores Acoplados a Proteínas G/genética , Factores de Transcripción/genética , Western Blotting , Ciclooxigenasa 2/genética , Regulación de la Expresión Génica , Células HEK293 , Humanos , Luciferasas/genética , Luciferasas/metabolismo , Neoplasias/metabolismo , Neoplasias/patología , Óxido Nítrico Sintasa de Tipo II/genética , Regiones Promotoras Genéticas/genética , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Interferencia de ARN , Receptores Acoplados a Proteínas G/metabolismo , Factores de Transcripción/metabolismo , Factor A de Crecimiento Endotelial Vascular/genética
6.
J Vet Med Sci ; 71(11): 1499-508, 2009 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-19959902

RESUMEN

Use of porcine tissues has been suggested as a promising solution for severe shortage of transplantable human organs. The immediate hurdle for xenotransplantation is acute immune/inflammatory vascular rejection of the transplant. Because endothelial cells play a key role in the initiation and the amplification of inflammation, alteration of gene expression in human endothelial cells, by various inflammatory stimulators has been studied extensively. However, transcriptional changes induced by human and other inflammatory stimulators in porcine endothelial cells have thus far not been studied. In this study, we treated porcine endothelial cells with human tumor necrosis factor (TNF)-alpha, porcine interferon (IFN)-gamma, H(2)O(2) and lypopolysaccharide (LPS) and profiled transcriptional change at 1 hr, 6 hr and 24 hr, using pig oligonucleotide 13K microarray. We found that mRNA species such as chemokine (C-X-C motif) ligand 6 (CXCL6) and Cathepsin S were significantly induced in porcine endothelial cells, as was previously reported with human endothelial cell. We also found that mRNA species including secreted frizzled-related protein 2 (SFRP2), radical S-adenosyl methionine domain containing 2 (RSAD2), structure specific recognition protein 1 (SSRP1) also were highly overexpressed in porcine endothelial cells. This result shows clues to understand underlying mechanisms of xenotransplantation rejection and the highly responsive porcine genes may serve as novel targets to be regulated for improving the function of grafted porcine donor organs.


Asunto(s)
Aorta/citología , Células Endoteliales/efectos de los fármacos , Peróxido de Hidrógeno/farmacología , Interferón gamma/farmacología , Lipopolisacáridos/farmacología , Factor de Necrosis Tumoral alfa/farmacología , Animales , Regulación de la Expresión Génica , Glicoproteínas/genética , Glicoproteínas/metabolismo , Humanos , Inflamación , Porcinos
7.
J Cancer Res Clin Oncol ; 135(1): 45-52, 2009 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-18592268

RESUMEN

PURPOSE: Lysophosphatidic acid (LPA) is a multifunctional lipid mediator involved in triggering tumor cell invasion and metastasis, as well as malignant cell growth. LPA is also known to modulate the colony scattering of epithelial cancers, which is a prerequisite for cell invasion. However, the underlying details of how this is accomplished are not clear. Here we have investigated the roles of specific LPA receptor subtypes in cell scattering. METHODS: Gastrointestinal carcinoma cell lines were examined for cell scattering activity in response to LPA, and the expression of LPA receptor subtypes was determined by RT-PCR. The effect of down regulation of each LPA receptor in DLD1 cells was determined using a shRNA-lentivirus system. In addition, the effect of overexpression of LPA receptors on cell scattering was investigated using lentivirus expression constructs. RESULTS: The colonies of AGS and DLD1, but not MKN74, cells were dispersed in response to LPA. RT-PCR analysis revealed that the mRNAs of LPA1, LPA2, and LPA3 were present in AGS and DLD1 cells, but only LPA2 mRNA was detected in MKN74 cells. In DLD1 cells, the scattering activity induced by LPA was partially blocked by pretreatment with PP2 and PD98059, inhibitors of src kinase and MEK, respectively. LPA1 knockdown with shRNA decreased the degree of cell scattering induced by LPA. Knockdown of LPA2 or LPA3 had no effect on LPA-induced scattering. In addition, overexpression of LPA1 in DLD1 cells slightly decreased the response time of LPA-induced cell scattering. On the contrary, MKN74 cells expressing exogenous LPA1 did not respond to LPA by scattering. CONCLUSION: These results demonstrate that LPA1 mediates LPA-stimulated cell scattering of gastrointestinal carcinomas, but that activation of other intracellular pathways, besides those contributing to ERK phosphorylation, is also necessary for cell scattering in response to LPA.


Asunto(s)
Neoplasias Gastrointestinales/metabolismo , Lisofosfolípidos/metabolismo , Receptores del Ácido Lisofosfatídico/genética , Transducción de Señal , Western Blotting , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Neoplasias Gastrointestinales/genética , Neoplasias Gastrointestinales/patología , Humanos , Lentivirus/genética , ARN Mensajero/genética , ARN Mensajero/metabolismo , ARN Interferente Pequeño/farmacología , Receptores del Ácido Lisofosfatídico/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Células Tumorales Cultivadas
8.
Exp Mol Med ; 40(5): 495-504, 2008 Oct 31.
Artículo en Inglés | MEDLINE | ID: mdl-18985007

RESUMEN

Exposure to light can induce photoreceptor cell death and exacerbate retinal degeneration. In this study, mice with genetic knockout of several genes, including rhodopsin kinase (Rhok-/-), arrestin (Sag-/-), transducin (Gnat1-/-), c-Fos (c-Fos-/-) and arrestin/transducin (Sag-/-/Gnat1-/-), were examined. We measured the expression levels of thousands of genes in order to investigate their roles in phototransduction signaling in light-induced retinal degeneration using DNA microarray technology and then further explored the gene network using pathway analysis tools. Several cascades of gene components were induced or inhibited as a result of corresponding gene knockout under specific light conditions. Transducin deletion blocked the apoptotic signaling induced by exposure to low light conditions, and it did not require c-Fos/AP-1. Deletion of c-Fos blocked the apoptotic signaling induced by exposure to high intensity light. In the present study, we identified many gene transcripts that are essential for the initiation of light-induced rod degeneration and proposed several important networks that are involved in pro- and anti-apoptotic signaling. We also demonstrated the different cascades of gene components that participate in apoptotic signaling under specific light conditions.


Asunto(s)
Perfilación de la Expresión Génica , Fototransducción/genética , Degeneración Retiniana/genética , Animales , Apoptosis/efectos de la radiación , Quinasa 1 del Receptor Acoplado a Proteína-G/genética , Subunidades alfa de la Proteína de Unión al GTP/genética , Genes fos/genética , Luz/efectos adversos , Fototransducción/fisiología , Fototransducción/efectos de la radiación , Ratones , Ratones Noqueados , Análisis de Secuencia por Matrices de Oligonucleótidos , Retina/metabolismo , Retina/patología , Retina/efectos de la radiación , Degeneración Retiniana/etiología , Degeneración Retiniana/fisiopatología , Transducina/genética
9.
J Food Prot ; 71(10): 2048-52, 2008 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-18939751

RESUMEN

Amygdalin (laterile) is a cyanogenic glycoside commonly found in the pits of many fruits and raw nuts. When amygdalin-containing seeds are crushed and moistened, free cyanide is formed. Pits and nuts containing unusually high levels of amygdalin can therefore cause cyanide poisoning, and detection of amygdalin in food extracts can be a life-saving measure. In this study, we generated recombinant antibodies against amygdalin from a phage display of a combinatorial rabbit/human chimeric antibody library and used it in a sensitive competition enzyme immunoassay system to detect amygdalin in extracts of pits and nuts. The detection limit was determined to be 1 x 10(-9) M.


Asunto(s)
Amigdalina/análisis , Amigdalina/inmunología , Contaminación de Alimentos/análisis , Nueces/química , Semillas/química , Amigdalina/toxicidad , Animales , Enfermedades Transmitidas por los Alimentos/prevención & control , Frutas/química , Humanos , Técnicas para Inmunoenzimas/métodos , Conejos
10.
Cell Signal ; 20(11): 2127-33, 2008 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-18755269

RESUMEN

The transcriptional activation of NF-kappaB, a critical player in both physiological and pathological cellular responses to diverse cytokines, is dependent on IKK activation. Although molecular mechanisms underlying IKK activation have been well elucidated, the processes that negatively regulate IKK activity are still largely unknown. Using yeast two-hybrid screening, we have identified GbetaL as an interacting partner of IKKbeta. In this study, we demonstrate that GbetaL interacts with IKKalpha and IKKbeta in vitro and in vivo. The C-terminal WD domains of GbetaL are required for the interaction with both the kinase domain and leucine zipper domain of IKKbeta. Overexpression of GbetaL inhibits TNFalpha-induced activation of NF-kappaB signaling, while down-regulation of GbetaL expression by small interfering RNA enhances NF-kappaB activity. GbetaL constitutively interacts with IKKbeta, and this interaction is enhanced by TNFalpha treatment. GbetaL also inhibits TNFalpha-induced phosphorylation of IKKs. Taken together, these data suggest that GbetaL is involved in the negative regulation of TNFalpha-stimulated NF-kappaB signaling through a direct interaction with IKK.


Asunto(s)
Quinasa I-kappa B/metabolismo , Péptidos y Proteínas de Señalización Intracelular/metabolismo , FN-kappa B/metabolismo , Transducción de Señal/efectos de los fármacos , Factor de Necrosis Tumoral alfa/farmacología , Proteínas Adaptadoras Transductoras de Señales , Animales , Línea Celular , Activación Enzimática/efectos de los fármacos , Humanos , Quinasa I-kappa B/química , Proteínas I-kappa B/metabolismo , Péptidos y Proteínas de Señalización Intracelular/química , Ratones , Fosforilación/efectos de los fármacos , Unión Proteica/efectos de los fármacos , Mapeo de Interacción de Proteínas , Procesamiento Proteico-Postraduccional/efectos de los fármacos , Estructura Terciaria de Proteína , Homóloga LST8 de la Proteína Asociada al mTOR
11.
J Cancer Res Clin Oncol ; 134(1): 45-50, 2008 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-17622559

RESUMEN

PURPOSE: Cancer cells release a multitude of cytokines and growth factors that influence neighboring cells and help establish a favorable environment for tumor development. As part of our studies designed to elucidate the complex cellular interactions within the tumor microenvironment that facilitate tumor development, we investigated cancer cell-induced changes in gene expression in endothelial cells. METHODS: After treatment of human umbilical vein endothelial cells (HUVEC) with conditioned medium (CM) of SNUC5 colon cancer cells, gene expression profile in HUVEC was analyzed using cDNA microarray. Neutralizing antibodies against pro-inflammatory cytokines were used to identify the major effecter in SNUC5 CM. RESULTS: IL-8 was one of the four genes up-regulated over fourfold, and IL-1alpha in SNUC5 CM was revealed as a major effecter of IL-8 over-expression and release, which was nearly completely neutralized by anti-IL-1alpha antibody. Constitutive secretion of IL-1alpha was confirmed in many other human cancer cells. CONCLUSIONS: IL-1alpha is constitutively expressed in many human cancer cells and directly induces IL-8 secretion in neighboring endothelial cells.


Asunto(s)
Neoplasias del Colon/genética , Endotelio Vascular/metabolismo , Regulación Neoplásica de la Expresión Génica/fisiología , Interleucina-1alfa/genética , Interleucina-8/genética , Células Cultivadas , Neoplasias del Colon/patología , Medios de Cultivo Condicionados , Endotelio Vascular/efectos de los fármacos , Ensayo de Inmunoadsorción Enzimática , Perfilación de la Expresión Génica , Humanos , Análisis de Secuencia por Matrices de Oligonucleótidos , ARN Mensajero/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Venas Umbilicales/citología , Regulación hacia Arriba
12.
Proc Natl Acad Sci U S A ; 103(37): 13759-64, 2006 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-16945906

RESUMEN

RNAi is proving to be a powerful experimental tool for the functional annotation of mammalian genomes. The full potential of this technology will be realized through development of approaches permitting regulated manipulation of endogenous gene expression with coordinated reexpression of exogenous transgenes. We describe the development of a lentiviral vector platform, pSLIK (single lentivector for inducible knockdown), which permits tetracycline-regulated expression of microRNA-like short hairpin RNAs from a single viral infection of any naïve cell system. In mouse embryonic fibroblasts, the pSLIK platform was used to conditionally deplete the expression of the heterotrimeric G proteins Galpha12 and Galpha13 both singly and in combination, demonstrating the Galpha13 dependence of serum response element-mediated transcription. In RAW264.7 macrophages, regulated knockdown of Gbeta2 correlated with a reduced Ca(2+) response to C5a. Insertion of a GFP transgene upstream of the Gbeta2 microRNA-like short hairpin RNA allowed concomitant reexpression of a heterologous mRNA during tetracycline-dependent target gene knockdown, significantly enhancing the experimental applicability of the pSLIK system.


Asunto(s)
Marcación de Gen/métodos , Terapia Genética/métodos , Vectores Genéticos/genética , Genómica/métodos , Interferencia de ARN , Animales , Células Cultivadas , Fibroblastos/efectos de los fármacos , Fibroblastos/metabolismo , Subunidades alfa de la Proteína de Unión al GTP G12-G13/genética , Proteínas Fluorescentes Verdes/análisis , Proteínas Fluorescentes Verdes/genética , Células Madre Hematopoyéticas/efectos de los fármacos , Células Madre Hematopoyéticas/metabolismo , Lentivirus/genética , Macrófagos/efectos de los fármacos , Macrófagos/metabolismo , Ratones , MicroARNs/genética , MicroARNs/farmacología , Elemento de Respuesta al Suero/genética , Tetraciclina/farmacología , Transgenes
13.
Mol Pharmacol ; 69(6): 1871-8, 2006 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-16540597

RESUMEN

2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) is a widespread environmental pollutant with many toxic effects, including endocrine disruption, reproductive dysfunction, immunotoxicity, liver damage, and cancer. These are mediated by TCDD binding to and activating the aryl hydrocarbon receptor (AhR), a basic helix-loop-helix transcription factor. In this regard, targeting the AhR using novel small molecule inhibitors is an attractive strategy for the development of potential preventive agents. In this study, by screening a chemical library composed of approximately 10,000 compounds, we identified a novel compound, 2-methyl-2H-pyrazole-3-carboxylic acid (2-methyl-4-o-tolylazo-phenyl)-amide (CH-223191), that potently inhibits TCDD-induced AhR-dependent transcription. In addition, CH-223191 blocked the binding of TCDD to AhR and inhibited TCDD-mediated nuclear translocation and DNA binding of AhR. These inhibitory effects of CH-223191 prevented the expression of cytochrome P450 enzymes, target genes of the AhR. Unlike many known antagonists of AhR, CH-223191 did not have detectable AhR agonist-like activity or estrogenic potency, suggesting that CH-223191 is a specific antagonist of AhR. It is noteworthy that CH-223191 potently prevented TCDD-elicited cytochrome P450 induction, liver toxicity, and wasting syndrome in mice. Taken together, these results demonstrate that this novel compound, CH-223191, may be a useful agent for the study of AhR-mediated signal transduction and the prevention of TCDD-associated pathology.


Asunto(s)
Antídotos/farmacología , Compuestos Azo/farmacología , Citocromo P-450 CYP1A1/antagonistas & inhibidores , Dioxinas/antagonistas & inhibidores , Pirazoles/farmacología , Receptores de Hidrocarburo de Aril/antagonistas & inhibidores , Animales , Antídotos/química , Compuestos Azo/química , Línea Celular Tumoral , Citocromo P-450 CYP1A1/efectos de los fármacos , Dioxinas/metabolismo , Dioxinas/toxicidad , Evaluación Preclínica de Medicamentos , Humanos , Hígado/efectos de los fármacos , Hígado/patología , Masculino , Ratones , Ratones Endogámicos ICR , Transporte de Proteínas/efectos de los fármacos , Pirazoles/química , Receptores de Hidrocarburo de Aril/metabolismo
14.
Mol Cells ; 19(3): 375-81, 2005 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-15995354

RESUMEN

Phospholipase C-beta (PLC-beta) hydrolyses phosphatidylinositol 4,5-bisphosphate and generates inositol 1,4,5-trisphosphate in response to activation of various G protein-coupled receptors (GPCRs). Using glial cells from knock-out mice lacking either PLC-beta1 [PLC-beta1 (-/-)] or PLC-beta3 [PLC-beta3 (-/-)], we examined which isotype of PLC-beta participated in the cellular signaling events triggered by thrombin. Generation of inositol phosphates (IPs) was enhanced by thrombin in PLC-beta1 (-/-) cells, but was negligible in PLC-beta3 (-/-) cells. Expression of PLC-beta3 in PLC-beta3 (-/-) cells resulted in an increase in pertussis toxin (PTx)-sensitive IPs in response to thrombin as well as to PAR1-specific peptide, while expression of PLC-beta1 in PLC-beta1 (-/-) cells did not have any effect on IP generation. The thrombin-induced [Ca2+]i increase was delayed and attenuated in PLC-beta3 (-/-) cells, but normal in PLC-beta1 (-/-) cells. Pertussis toxin evoked a delayed [Ca2+]i increase in PLC-beta3 (-/-) cells as well as in PLC-beta1 (-/-) cells. These results suggest that activation of PLC-beta3 by pertussis toxin-sensitive G proteins is responsible for the transient [Ca2+]i increase in response to thrombin, whereas the delayed [Ca2+]i increase may be due to activation of some other PLC, such as PLC-beta4, acting via PTx-insensitive G proteins.


Asunto(s)
Calcio/metabolismo , Isoenzimas/fisiología , Neuroglía/metabolismo , Trombina/fisiología , Fosfolipasas de Tipo C/fisiología , Animales , Línea Celular , Activación Enzimática , Estrenos/farmacología , Proteínas de Unión al GTP Heterotriméricas/metabolismo , Fosfatos de Inositol/biosíntesis , Isoenzimas/biosíntesis , Isoenzimas/deficiencia , Ratones , Ratones Noqueados , Neuroglía/citología , Neuroglía/efectos de los fármacos , Toxina del Pertussis/farmacología , Fosfolipasa C beta , Pirrolidinonas/farmacología , Receptor PAR-1/biosíntesis , Tapsigargina/farmacología , Fosfolipasas de Tipo C/deficiencia
15.
Biochem Pharmacol ; 69(9): 1333-41, 2005 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-15826604

RESUMEN

We screened a library of 11,000 small molecular weight chemicals, looking for compounds that affect cell viability. We have identified 2-amino-N-quinoline-8-yl-benzenesulfonamide (QBS) as a potent cytotoxic compound that induces cell cycle arrest and apoptosis. Treatment of Jurkat T cells with QBS increased the levels of cyclin B1 as well as phosphorylated-cdc2, which was accompanied by reduced activity of cdc2 kinase, suggesting that QBS may induce cell cycle arrest at G2 phase. Structural analogues of QBS also exhibited similar effects on cell cycle progression and cell viability. Long-term treatment with QBS resulted in DNA fragmentation, cytochrome C release, and PARP cleavage, and an increase in the number of subdiploidy cells, indicative of cellular apoptosis. Moreover, QBS-induced apoptosis was blocked by z-VAD-fmk, a pan-caspase inhibitor. These results suggest that QBS is a novel and potent compound that induces G2 arrest and subsequent apoptosis, implicating it as a putative candidate for chemotherapy.


Asunto(s)
Apoptosis/efectos de los fármacos , Benceno/toxicidad , Fase G2/efectos de los fármacos , Quinolinas/toxicidad , Linfocitos T/efectos de los fármacos , Benceno/química , Caspasa 3 , Caspasas/metabolismo , Ciclo Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Ensayo Cometa , Ciclina B/metabolismo , Ciclina B1 , Fluoresceína-5-Isotiocianato , Colorantes Fluorescentes , Humanos , Células Jurkat , Propidio , Quinolinas/química , Linfocitos T/ultraestructura
16.
Biochem J ; 389(Pt 1): 181-6, 2005 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-15702972

RESUMEN

PLC (phospholipase C) plays an important role in intracellular signal transduction by hydrolysing phosphatidylinositol 4,5-bisphosphate, a membrane phospholipid. To date, 12 members of the mammalian PLC isoforms have been identified and classified into five isotypes beta, gamma, delta, epsilon and zeta, which are regulated by distinct mechanisms. In the present study, we describe the identification of a novel PLC isoform in the brains of human and mouse, named PLC-eta, which contains the conserved pleckstrin homology domain, X and Y domains for catalytic activity and the C2 domain. The first identified gene encoded 1002 (human) or 1003 (mouse) amino acids with an estimated molecular mass of 115 kDa. The purified recombinant PLC-eta exhibited Ca2+-dependent catalytic activity on phosphatidylinositol 4,5-bisphosphate. Furthermore, molecular biological analysis revealed that the PLC-eta gene was transcribed to several splicing variants. Although some transcripts were detected in most of the tissues we examined, the transcript encoding 115 kDa was restricted to the brain and lung. In addition, the expression of the 115 kDa protein was defined in only nerve tissues such as the brain and spinal cord. In situ hybridization analysis with brain revealed that PLC-eta was abundantly expressed in various regions including cerebral cortex, hippocampus, zona incerta and cerebellar Purkinje cell layer, which are neuronal cell-enriched regions. These results suggest that PLC-eta may perform fundamental roles in the brain.


Asunto(s)
Fosfolipasas de Tipo C/genética , Fosfolipasas de Tipo C/metabolismo , Secuencia de Aminoácidos , Animales , Encéfalo/enzimología , Clonación Molecular , Perfilación de la Expresión Génica , Humanos , Ratones , Datos de Secuencia Molecular , Fosfoinositido Fosfolipasa C , Filogenia , Homología de Secuencia de Aminoácido , Fosfolipasas de Tipo C/química , Fosfolipasas de Tipo C/clasificación
17.
Toxicol Sci ; 83(2): 397-404, 2005 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-15525691

RESUMEN

Polychlorinated biphenyls (PCBs), a group of persistent and widespread environmental pollutants, are considered to be immunotoxic, carcinogenic, and to induce apoptosis. However, the cellular mechanisms underlying the action of PCBs have not been established. Here, we investigated the effects of PCBs on the induction of cyclooxygenase-2 (COX-2). Among the several congeners examined, only 2,2',4,6,6'-pentachlorobiphenyl (PeCB) specifically increased the COX-2 promoter activity, and the levels of COX-2 mRNA and protein, and thereby enhanced prostaglandin E2 (PGE2) synthesis in Rat-1 cells. By conducting mutation analyses of the COX-2 promoter and its transcription factor, we found that the CRE site in COX-2 promoter and c-Jun are important for increased COX-2 promoter activity induced by 2,2',4,6,6'-PeCB. In addition, 2,2',4,6,6'-PeCB-stimulated COX-2 induction was reduced by the specific MAPK kinase (MEK) inhibitor, PD98059, and in p53-deficient cells, implying that COX-2 induction requires the activation of ERK1/2 MAPK and p53. The selective COX-2 inhibitor, NS-398, potentiated the 2,2',4,6,6'-PeCB-induced mitochondrial apoptotic pathway involved in Bcl-xL attenuation, cytochrome c release and the subsequent activation of caspase-3. Furthermore, the cell death was prevented by PGE2 treatment, suggesting that 2,2',4,6,6'-PeCB-induced apoptosis is restricted by prostaglandin upregulation by COX-2. Taken together, these results demonstrate that 2,2',4,6,6'-PeCB-induced COX-2 expression may be an important compensatory mechanism for abating 2,2',4,6,6'-PeCB toxicity.


Asunto(s)
Apoptosis/efectos de los fármacos , Contaminantes Ambientales/toxicidad , Fibroblastos/efectos de los fármacos , Regulación Enzimológica de la Expresión Génica/efectos de los fármacos , Bifenilos Policlorados/toxicidad , Prostaglandina-Endoperóxido Sintasas/biosíntesis , Animales , Células Cultivadas , Ciclooxigenasa 2 , Análisis Mutacional de ADN , Dinoprostona/biosíntesis , Dinoprostona/genética , Inducción Enzimática , Fibroblastos/enzimología , Fibroblastos/patología , Ratones , Prostaglandina-Endoperóxido Sintasas/genética , ARN Mensajero/metabolismo , Ratas , Elementos de Respuesta/efectos de los fármacos , Transfección
18.
Toxicol Sci ; 78(2): 215-21, 2004 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-14737002

RESUMEN

Polychlorinated biphenyls (PCBs), a class of persistent organic pollutants (POPs), have been considered to be involved in cancers, but the underlying mechanisms are not known well. Various cancers are closely related to genetic alteration; therefore, we investigated the effect of PCBs on genetic stability, through p53, a guardian of genome, in NIH 3T3 fibroblasts. Among several congeners examined, 2,2',4,6,6'-pentachlorobiphenyl (PeCB) specifically activated p53-dependent transcription. It also induced p53 nuclear accumulation, but did not cause DNA strand breakage. On the other hand, cell cycle progression that is closely connected to p53 was affected by 2,2',4,6,6'-PeCB, resulting in mitotic arrest. In the arrested cells, mitotic spindle damage was detected. Moreover, in the absence of functional p53, polyploidy was caused by 2,2',4,6,6'-PeCB. These results imply that 2,2',4,6,6'-PeCB induces mitotic arrest by interfering with mitotic spindle assembly, followed by genetic instability which triggers p53-activating signals to prevent further polyploidization. Taking these findings together, we suggest that 2,2',4,6,6'-PeCB could be involved in cancer development by causing genetic instability through mitotic spindle damage, which brings about aneuploidy in p53-deficient tumor cells.


Asunto(s)
Contaminantes Ambientales/toxicidad , Mitosis/efectos de los fármacos , Bifenilos Policlorados/toxicidad , Poliploidía , Proteína p53 Supresora de Tumor/metabolismo , Animales , Proteína Quinasa CDC2 , Ensayo Cometa , Luciferasas , Ratones , Células 3T3 NIH , Huso Acromático/efectos de los fármacos , Proteína p53 Supresora de Tumor/deficiencia , Proteína p53 Supresora de Tumor/genética
19.
Biochem Pharmacol ; 66(6): 955-63, 2003 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-12963482

RESUMEN

Flavonoids are natural polyphenolic compounds that have anti-inflammatory, cytoprotective and anticarcinogenic effects. In this study, we investigated the effects of several flavonoids on nuclear factor-kappa B (NF-kappa B) activation by using luciferase reporter gene assay. Among the flavonoids examined, luteolin showed the most potent inhibition on lipopolysaccharide (LPS)-stimulated NF-kappa B transcriptional activity in Rat-1 fibroblasts. Luteolin did not inhibit either I kappa B alpha degradation or NF-kappa B nuclear translocation, DNA binding or phosphorylation by LPS. However, luteolin prevented LPS-stimulated interaction between the p65 subunit of NF-kappa B and the transcriptional coactivator CBP. In addition, a specific PKA inhibitor that blocked the phosphorylation of CREB and c-Jun by luteolin partially reversed the inhibitory effect of luteolin on NF-kappa B.CBP complex formation and NF-kappa B transcriptional activity by LPS. These data imply that inhibition of NF-kappa B transcriptional activity by luteolin may occur through competition with transcription factors for coactivator that is available in limited amounts. Taken together, this study provides a molecular basis for the understanding of the anti-inflammatory effects of luteolin.


Asunto(s)
Proteínas de Unión al ADN , Fibroblastos/efectos de los fármacos , Flavonoides/farmacología , FN-kappa B/metabolismo , Transcripción Genética/efectos de los fármacos , Factor de Transcripción Activador 1 , Transporte Activo de Núcleo Celular/efectos de los fármacos , Animales , Células Cultivadas , Proteína de Unión a Elemento de Respuesta al AMP Cíclico/metabolismo , ADN/efectos de los fármacos , ADN/metabolismo , Interacciones Farmacológicas , Fibroblastos/metabolismo , Proteínas I-kappa B/metabolismo , Proteínas Quinasas JNK Activadas por Mitógenos , Lipopolisacáridos/farmacología , Luteolina , Proteínas Quinasas Activadas por Mitógenos/metabolismo , Inhibidor NF-kappaB alfa , Fosforilación/efectos de los fármacos , Ratas , Factores de Transcripción/metabolismo
20.
Neurotoxicology ; 24(3): 425-34, 2003 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-12782107

RESUMEN

The neurotoxicity of dithiocarbamates has been previously reported, however, the detailed mechanism underlying the neurotoxicity is still not fully understood. Among the dithiocarbamates, we investigated thiram and ziram in a neuronal-like pheochromocytoma (PC12) cells. Thiram and ziram strongly induced cell death in both dose- and time-dependent manners with the LC(50) of 0.3 and 2 microM, respectively. The cell death showed typical apoptotic features, such as DNA fragmentation and an increase of subdiploidy nuclei. Interestingly, both thiram and ziram induced rapid and sustained increases of intracellular Ca(2+) in PC12 cells, which were almost completely blocked by flufenamic acid (FFA), an inhibitor of non-selective cation channel. BAPTA-AM, an intracellular Ca(2+) chelator, inhibited the thiram- and ziram-induced apoptotic cell death. These results suggest that thiram and ziram induce apoptotic neuronal cell death by Ca(2+) influx through non-selective cation channels. The present study may provide a clue for understanding the mechanism of neurotoxicity of thiram and ziram.


Asunto(s)
Apoptosis/efectos de los fármacos , Canales Iónicos/metabolismo , Tiram/farmacología , Ziram/farmacología , Animales , Apoptosis/fisiología , Calcio/metabolismo , Supervivencia Celular/efectos de los fármacos , Supervivencia Celular/fisiología , Relación Dosis-Respuesta a Droga , Canales Iónicos/agonistas , Canales Iónicos/antagonistas & inhibidores , Células PC12 , Ratas
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