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1.
Pak J Pharm Sci ; 36(1): 89-97, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36967501

RESUMEN

Development of adjuvant chemotherapy drugs against drug-resistant lung cancer cells is necessary. The use of non-toxic adjuvant natural product combined with chemotherapy drugs will be an important treatment mode in the future. The purpose of the study investigates that fucoidan enhances chemotherapy drug poisoning drug-resistant lung cancer cell. Drug-resistant lung cancer cells are established in the study. Cell culture, MTT assay, wound healing assay, gelatin zymography assay, DNA fragmentation assay, apoptosis assay, reverse transcription polymerase chain reaction (RT-PCR) western blot analysis was adopted. The results showed that fucoidan synergized with doxorubicin increased efficacy of poisoning drug-resistant lung cancer cells and enhanced the ability of doxorubicin to inhibit the migration of drug-resistant lung cancer cells. It was observed that fucoidan synergized with doxorubicin induced the increase of apoptosis and inhibited expression of MMP-9, LC3, Beclin-1 and ß-catenin in drug-resistant lung cancer cells. Fucoidan synergized with doxorubicin significantly inhibited proliferation, migration and metastasis of drug-resistant lung cancer cells. Fucoidan strengthened doxorubicin to induce apoptosis and autophagy of drug-resistant lung cancer cells. This study confirms that the combined use of fucoidan and chemotherapeutic drugs can effectively poison drug-resistant lung cancer cells.


Asunto(s)
Neoplasias Pulmonares , Humanos , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/metabolismo , Apoptosis , Polisacáridos/farmacología , Polisacáridos/uso terapéutico , Doxorrubicina/farmacología , Doxorrubicina/uso terapéutico , Proliferación Celular , Línea Celular Tumoral
2.
Eur J Cell Biol ; 100(5-6): 151169, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34273665

RESUMEN

Vascular smooth muscle cells (SMCs) are important vascular components that are essential for the regulation of vascular functions during vascular atherosclerogenesis and vascular injury. Oxidized low-density lipoprotein (oxLDL) is known to induce SMC activation and foam cell transformation. This study characterized the role of hepatoma-derived growth factor (HDGF) in oxLDL-induced foam cell formation in cultured primary rat aortic SMCs. OxLDL exposure significantly increased HDGF expression and extracellular release. It also upregulated atherogenic regulators in SMCs, including TLR4, MyD88, LOX-1, and CD36. Exogenous HDGF stimulation not only increased the expression of cognate receptor nucleolin, but also the innate immunity regulators TLR4/MyD88 and lipid metabolism regulators, including LOX-1 and CD36. Oil red O staining showed that HDGF did not initiate, but enhanced oxLDL-driven foam cell formation in SMCs. Further signaling characterization demonstrated that oxLDL evoked activation of PI3K/Akt and p38 MAPK signaling pathways, both of which were involved in the upregulation of HDGF, LOX-1, and CD36 induced by oxLDL. Gene knockdown experiments using LOX-1 targeted siRNA demonstrated that LOX-1 expression was critical for oxLDL-induced HDGF upregulation, while HDGF gene depletion completely abolished oxLDL-triggered TLR4, LOX-1, and CD36 overexpression and foam cell formation in SMCs. These findings strongly suggest that oxLDL-induced HDGF upregulation participates in subsequent LOX-1 and CD36 expression in aortic SMCs and mechanistically contributes to the formation of SMC-derived foam cells. The oxLDL/LOX-1/HDGF axis may serve as a target for anti-atherogenesis therapy.


Asunto(s)
Células Espumosas , Músculo Liso Vascular , Animales , Células Cultivadas , Células Espumosas/metabolismo , Péptidos y Proteínas de Señalización Intercelular , Lipoproteínas LDL/metabolismo , Fosfatidilinositol 3-Quinasas , Ratas , Regulación hacia Arriba
3.
Life Sci ; 256: 117964, 2020 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-32534036

RESUMEN

AIMS: Vascular smooth muscle cells (VSMCs) are important regulators of vascular functions and their conversion to osteoblasts is a key to development of vascular calcification. This study aimed to characterize in vitro effect of hepatoma-derived growth factor (HDGF) on phenotypic conversion of cultured aortic VSMCs into osteoblast-like cells. MATERIALS AND METHODS: Cell proliferation and migration assays were used to examine cell behaviors. Western blotting, alkaline phosphatase activity and calcium staining were used to evaluate osteoblastic marker expression and function, respectively. KEY FINDINGS: Recombinant HDGF treatment enhanced VSMC growth and motility. Treatment of osteogenic medium (OM) increased expression of not only HDGF but also osteoblastic markers, including Runx2 and osteopontin (OPN), while VSMC marker α-smooth muscle actin (α-SMA) declined. Coincidentally, HDGF and OM treatment alone stimulated signaling activities in both PI3K/Akt and MAPK pathways. Conversely, inhibition of Akt and p38 significantly blocked the OM-upregulated HDGF, Runx2, and OPN expression and NF-κB phosphorylation, but did not reversed the α-SMA downregulation, implicating the involvement of Akt and p38 activities in the osteoblastic transformation of VSMCs. Small interfering RNA-mediated HDGF gene silencing effectively prevented the Runx2 and OPN upregulation, alkaline phosphatase activation, and calcium deposition, but did not affect the α-SMA levels in the transformed cells, supporting the involvement of HDGF in regulation of Runx2 and OPN expression. SIGNIFICANCE: In conclusion, in synergism with other osteogenic factor, HDGF may promote the progression of osteobastic transformation of VSMCs via Akt and p38 signaling pathways and contribute to vascular calcification in arteriosclerosis. CHEMICAL COMPOUNDS STUDIED IN THIS STUDY: HDGF (PubChem CID:); LY294002 (PubChem CID: 3973); PD98059 (PubChem CID: 4713); SB203580 (PubChem CID: 176155); SB431542 (PubChem CID: 4521392); SP600125 (PubChem CID: 8515); Wortmannin (PubChem CID: 312145).


Asunto(s)
Péptidos y Proteínas de Señalización Intercelular/farmacología , Músculo Liso Vascular/citología , Miocitos del Músculo Liso/citología , Osteoblastos/citología , Animales , Biomarcadores/metabolismo , Línea Celular Transformada , Movimiento Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Células Cultivadas , Subunidad alfa 1 del Factor de Unión al Sitio Principal/metabolismo , Silenciador del Gen/efectos de los fármacos , Cinética , Miocitos del Músculo Liso/efectos de los fármacos , Osteoblastos/efectos de los fármacos , Osteoblastos/metabolismo , Osteogénesis/efectos de los fármacos , Osteopontina/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Ratas Sprague-Dawley , Regulación hacia Arriba/efectos de los fármacos , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo
4.
J Cosmet Dermatol ; 19(2): 540-552, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31243886

RESUMEN

BACKGROUND: Farnesol is an acyclic sesquiterpene presents in various natural sources including fruits, vegetables, and herbs. In this study, we successfully prepared a farnesol-containing gel with ultraviolet B-screening and skin-repairing capabilities. Furthermore, the advantageous potential of farnesol-containing facial masks for UVB-caused sunburnt skin was evaluated. AIMS: Thus, the objectives of this study are to design and prepare optimal facial masks possessing collagen production and smoothness-enhancing capabilities for the skin. METHODS: A series of formulations consisting of hydroxypropyl methylcellulose, hyaluronan, and farnesol were used to prepare the facial masks. The effects of the facial masks on collagen production by skin fibroblasts in vitro were examined. The effects of the prepared masks on collagen synthesis, smoothness, and inflammation of the skin were further evaluated in vivo using two modes (mask administration interspersed with UVB exposure and mask administration after UVB exposure) of a rat model. RESULTS: Facial masks containing both 0.3 and 0.8 mM farnesol improved skin smoothness and enhanced collagen content and arrangement in the skin of rats with mask administration interspersed with and after UVB exposure. The masks containing 0.8 mM farnesol exerted the greatest effects on collagen production/arrangement and smoothness improvement in vivo model. Histopathologically observed inflammation was alleviated, and interleukin (IL)-6 was decreased in the 0.8 mM farnesol-containing facial mask-covered skin compared with that without facial masks. CONCLUSIONS: The farnesol-containing facial masks prepared in this study may have collagen production-increasing, smoothness-improving, and anti-inflammatory properties for UVB-caused sunburn; thus, farnesol is potentially a beneficial component in facial masks.


Asunto(s)
Cosmecéuticos/administración & dosificación , Farnesol/administración & dosificación , Envejecimiento de la Piel/efectos de los fármacos , Piel/efectos de los fármacos , Quemadura Solar/tratamiento farmacológico , Animales , Línea Celular , Cosmecéuticos/química , Modelos Animales de Enfermedad , Cara , Farnesol/química , Femenino , Fibroblastos , Geles , Humanos , Ácido Hialurónico/administración & dosificación , Ácido Hialurónico/química , Derivados de la Hipromelosa/administración & dosificación , Derivados de la Hipromelosa/química , Ratones , Ratas , Piel/efectos de la radiación , Envejecimiento de la Piel/efectos de la radiación , Rayos Ultravioleta/efectos adversos
5.
Environ Toxicol ; 33(4): 488-507, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29380558

RESUMEN

Farnesol, a natural 15-carbon organic compound, has various microbiological and cellular activities. It has been found to exert apoptosis-inducing effects against carcinoma cells as well as antiallergic and anti-inflammatory effects in vivo. In the current study, a series of formulations composed of various concentrations of hydroxypropyl methylcellulose (HPMC) with the addition of hyaluronan (HA) and xanthan gum (XG) was designed to evaluate the UVB-screening and H2 O2 -eliminating effects of farnesol in normal fibroblasts. Farnesol at 0.005, 0.0075, and 0.01% exhibited significant capacity for H2 O2 scavenging; at 0.0025%, it showed insignificant effects. Under 120-min UVB exposure, screening with plural gel composed of 0.0025% farnesol, 0.5% HA, and 0.5% XG containing 1.5% or 2% HPMC retained normal fibroblast viability. After 60-min exposure to UVB, screening with plural gel composed of farnesol, HA, XG, and 0.5%, 1.0%, 1.5%, or 2% HPMC decreased the ratio of the G1 phase and increased ratio of the S phase in comparison with the accumulated cell cycle of the normal fibroblasts without screening. The gel with 2% HPMC displayed the strongest cell cycle-reversal ability. In vivo histopathological results showed that the prepared plural gels with 0.5% or 2% HPMC and farnesol, HA, and XG had greater antiphotoaging and reparative effects against UVB-induced changes and damage in the skin. In conclusion, the current in vitro and in vivo results demonstrated that the prepared plural composed of 0.0025% farnesol, 0.5% HA, 0.5% XG, and 2% HPMC possessed the greatest UVB-screening capacity and the strongest restorative effects on UVB-induced sunburned skin.


Asunto(s)
Farnesol/uso terapéutico , Quemadura Solar/tratamiento farmacológico , Ciclo Celular/efectos de los fármacos , Fibroblastos/efectos de los fármacos , Fibroblastos/patología , Ácido Hialurónico , Peróxido de Hidrógeno/toxicidad , Derivados de la Hipromelosa , Polisacáridos Bacterianos , Piel/efectos de los fármacos , Piel/patología , Quemadura Solar/patología , Protectores Solares , Rayos Ultravioleta
6.
Toxicol In Vitro ; 42: 101-104, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28412505

RESUMEN

UVB is a potent modulator of cell growth and differentiation in the skin. The UVB irradiation has been used in treating hyperproliferative dermatoses. Otherwise, UVB radiation is also the major risk factor for developing skin cancer. Nitric oxide (NO) has been suggested to be a physiological modulator of cell proliferation. Raf-1 kinase inhibitory protein (RKIP) was involved in cell growth, transformation, and differentiation. The purpose of this study was to search for the possible cause of UVB-inhibited hyperplasia and UVB-resulted hyperproliferation. We evaluated various UVB dose whether affect the expression of RKIP, iNOS, NO and proliferation in keratinocyte. Normal human keratinocytes were treated with UVB dose of 40mJ/cm2, 80mJ/cm2, 120mJ/cm2, 160mJ/cm2 and 0mJ/cm2 (control group) respectively. The results showed that RKIP, iNOS and NO of keratinocytes with doses of 40mJ/cm2 and 80mJ/cm2 UVB treatment significantly higher than control group (P<0.01). The proliferation of keratinocyte with doses of 40mJ/cm2 and 80mJ/cm2 UVB treatment was significantly lower than control group (P<0.01). However, RKIP, iNOS and NO of keratinocytes with doses of 120mJ/cm2 and 160mJ/cm2 UVB treatment significantly lower than control group (P<0.01). The proliferation of keratinocyte with doses of 120mJ/cm2 and 160mJ/cm2 UVB treatment was significantly higher than control group (P<0.01). In conclusion, these results showed that the different UVB dosages induced various alteration of RKIP, NO, iNOS and proliferation may provide important information on the therapeutic molecular mechanism of UVB-inhibited hyperplasia and UVB resulted hyperproliferation.


Asunto(s)
Queratinocitos/efectos de la radiación , Óxido Nítrico Sintasa de Tipo II/metabolismo , Óxido Nítrico/metabolismo , Proteínas de Unión a Fosfatidiletanolamina/metabolismo , Rayos Ultravioleta , Proliferación Celular/efectos de la radiación , Células Cultivadas , Humanos , Queratinocitos/metabolismo
7.
Environ Toxicol ; 32(3): 1079-1082, 2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-27255443

RESUMEN

Arsenic is associated with cancers of kidney and liver. Raf kinase inhibitor protein (RKIP) has been identified as a member of a novel class of molecules that suppress the metastatic spread of tumors. In order to investigate the effect of arsenic to RKIP of liver and kidney, the expression of RKIP of liver and kidney with As (III) was explored in this study. Thirty male mice were chronically fed with 42.5 ppm, 85 ppm NaAsO2 and water for 180 days. The kidney and liver accumulation levels of As (III) in mice were determined by electro-thermal atomic absorption spectrometry. The method of RT-PCR, Western blotting analysis and immunohistochemistry were used to determine gene expression and protein expression of RKIP. The results showed that arsenic level was significantly increased in kidney and liver of As (III)-exposed mice as compared with control group. The gene expression and protein expression of RKIP was significantly decreased in kidney and liver of As (III)-exposed mice in comparison with these of control mice. These data suggested that RKIP decrease of liver and kidney with As (III) may be dangerous index in formation of cancer. © 2016 Wiley Periodicals, Inc. Environ Toxicol 32: 1079-1082, 2017.


Asunto(s)
Arsénico/toxicidad , Riñón/efectos de los fármacos , Hígado/efectos de los fármacos , Proteínas de Unión a Fosfatidiletanolamina/genética , Animales , Intoxicación por Arsénico/genética , Intoxicación por Arsénico/metabolismo , Intoxicación por Arsénico/patología , Western Blotting , Regulación de la Expresión Génica/efectos de los fármacos , Inmunohistoquímica , Riñón/metabolismo , Hígado/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Proteínas de Unión a Fosfatidiletanolamina/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
8.
J Appl Toxicol ; 31(8): 730-40, 2011 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-21437922

RESUMEN

Hexavalent chromium (CrVI) is considered to be a risk factor in the formation of human cancer. Raf kinase inhibitor protein (RKIP), Rho-GDIα, galectin, c-Myc and p53 play important roles in cancer formation. The purpose of this study was to determine if Cr(VI) induces the formation of gastrointestinal cancer. We explored the expression of RKIP, Rho-GDIα, galectin, c-Myc and p53 in the colon and stomach in rats exposed to chromium (CrVI). Thirty Wistar rats were divided into six groups which were chronically fed with 250, 500, 750, 1000 and 1250 ppm Na(2) Cr(2) O(7) and water for 60 days. The level of Cr(VI) was determined by electrothermal atomic absorption spectrometry. The expression of RKIP, Rho-GDIα, galectin, c-Myc and p53 of stomach and colon was measured by western blot. The gene expression of RKIP, Rho-GDIα, galectin, c-Myc and p53 of the stomach and colon was determined by RT-PCR. The results showed that the expression of p53 and Rho-GDIα was decreased in the stomach and colon of rats with Cr(VI) treatment. The expression of RKIP was decreased in the stomach and colon of rats treated with high-dose Cr(VI). The expression of c-Myc and gelectin-1 was increased in the stomach and colon of rats with Cr(VI) treatment. We concluded that the anomalous expression of RKIP, Rho-GDIα, galectin, c-Myc and p53 might be a dangerous index of cancer formation in the stomach and colon of rats with Cr(VI) exposure.


Asunto(s)
Cromo/toxicidad , Galectinas/genética , Tracto Gastrointestinal/efectos de los fármacos , Inhibidores de Disociación de Guanina Nucleótido/genética , Proteínas de Unión a Fosfatidiletanolamina/genética , Proteínas Proto-Oncogénicas c-myc/genética , Proteína p53 Supresora de Tumor/genética , Animales , Apoptosis/efectos de los fármacos , Western Blotting , Galectinas/metabolismo , Tracto Gastrointestinal/patología , Regulación de la Expresión Génica , Inhibidores de Disociación de Guanina Nucleótido/metabolismo , Masculino , Proteínas de Unión a Fosfatidiletanolamina/metabolismo , Proteínas Proto-Oncogénicas c-myc/metabolismo , Ratas , Ratas Wistar , Espectrofotometría Atómica , Proteína p53 Supresora de Tumor/metabolismo , Inhibidor alfa de Disociación del Nucleótido Guanina rho , Inhibidores de la Disociación del Nucleótido Guanina rho-Específico
9.
Phytomedicine ; 17(6): 469-74, 2010 May.
Artículo en Inglés | MEDLINE | ID: mdl-19683908

RESUMEN

Although magnolol is cytoprotective against warm ischemia/reperfusion injury, its effect on cold preservation has not been fully investigated. This study aimed at examining whether magnolol maintains the liver graft integrity after cold preservation and elucidating the underlying mechanisms in terms of apoptotic signaling under both normothermic and hypothermic conditions. After being preserved in Ringer's lactate (RL) at 4 degrees C for 6h ex vivo, the magnolol-treated grafts demonstrated significantly higher AST, ALT, and LDH levels in perfusates than those from negative controls. TUNEL staining showed no difference in the number of apoptotic nuclei in both groups, whereas a more intense apoptotic signal in magnolol-treated grafts was shown as compared with the controls. In vitro data showed no significant difference in viability of RL-preserved clone-9 hepatocytes between the magnolol-treated and control groups, while magnolol pretreatment at 30min before cold preservation prominently induced hepatocyte cell death. RT-PCR and Western blotting analyses revealed a suppression in Bcl-2, but an up-regulation in Bax expression in clone-9 cells after magnolol treatment. Magnolol suppressed the ratios of NF-kappaB to I-kappaBalpha protein contents and I-kappaBalpha phosphorylation induced by TNF-alpha, and potentiated mitochondrial cytochrome c release and subsequent caspase-3 cleavage. Conversely, caspase-3 inhibitor attenuated magnolol-induced hepatotoxicity. We concluded that magnolol could not protect liver grafts from cold ischemia/reperfusion injury. High concentration of magnolol under serum-reduced conditions attenuates NF-kappaB-mediated signaling and induces intrinsic apoptotic pathway, thereby inducing in vitro hepatotoxicity.


Asunto(s)
Apoptosis/efectos de los fármacos , Compuestos de Bifenilo/toxicidad , Enfermedad Hepática Inducida por Sustancias y Drogas/etiología , Criopreservación , Lignanos/toxicidad , Trasplante de Hígado , Hígado/efectos de los fármacos , Magnolia/química , Extractos Vegetales/toxicidad , Daño por Reperfusión , Transducción de Señal/efectos de los fármacos , Animales , Compuestos de Bifenilo/administración & dosificación , Western Blotting , Caspasa 3/metabolismo , Enfermedad Hepática Inducida por Sustancias y Drogas/metabolismo , Frío , Citocromos c/metabolismo , Proteínas I-kappa B/metabolismo , Etiquetado Corte-Fin in Situ , Lignanos/administración & dosificación , Hígado/metabolismo , Masculino , Mitocondrias/efectos de los fármacos , FN-kappa B/metabolismo , Corteza de la Planta , Extractos Vegetales/química , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Ratas , Ratas Sprague-Dawley , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Suero , Factor de Necrosis Tumoral alfa/metabolismo , Proteína X Asociada a bcl-2
10.
Angiology ; 58(2): 161-8, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17495264

RESUMEN

Blackfoot disease is an endemic arsenic-induced peripheral vascular disease in southern Taiwan. The main pathologic feature is atherosclerosis, which may relate to imbalances of the adrenergic system. The purpose of this study is to investigate the peripheral adrenergic responses of patients with blackfoot disease. Eight patients with blackfoot disease and four age-matched healthy controls were enrolled in this study. Baseline cutaneous perfusion was measured with a laser Doppler flowmeter. The response of alpha-adrenoceptors in the cutaneous microcirculation was assessed with laser Doppler flowmetry with iontophoresis of phenylephrine into the nailfold. In vitro binding with (125)I-cyanopindolol determined beta-adrenoceptor density in lymphocytes. The cyclic adenosine monophosphate (cAMP) level at baseline and after isoproterenol stimulation reflects lymphocyte beta-adrenergic responsiveness. Results revealed persistently decreased skin perfusion in patients with blackfoot disease. In contrast, there was a transient decrease in skin perfusion in healthy controls after iontophoresis of phenylephrine. Both beta-2 receptor density and isoproterenol-stimulated cAMP levels in lymphocytes decreased. Increased peripheral alpha-adrenergic response and decreased beta-2-adrenergic response are related to increased vascular tone and result in atherosclerosis. Our findings of accentuated alpha-adrenergic response in microcirculation and decreased lymphocyte beta-2-adrenoceptor response play an important role in the pathogenesis of atherosclerosis in blackfoot disease.


Asunto(s)
Intoxicación por Arsénico/complicaciones , Pierna/irrigación sanguínea , Enfermedades Vasculares Periféricas/inducido químicamente , Enfermedades Vasculares Periféricas/fisiopatología , Receptores Adrenérgicos/efectos de los fármacos , Contaminantes Químicos del Agua/envenenamiento , Abastecimiento de Agua , Agonistas Adrenérgicos beta/farmacología , Anciano , Anciano de 80 o más Años , Intoxicación por Arsénico/epidemiología , Velocidad del Flujo Sanguíneo , Estudios de Casos y Controles , AMP Cíclico/metabolismo , Femenino , Humanos , Iontoforesis , Isoproterenol/farmacología , Flujometría por Láser-Doppler , Linfocitos/efectos de los fármacos , Masculino , Microcirculación , Persona de Mediana Edad , Enfermedades Vasculares Periféricas/epidemiología , Factores de Riesgo , Taiwán/epidemiología
11.
Cancer Lett ; 233(1): 165-71, 2006 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-15905022

RESUMEN

It has been reported that the mutational inactivation of the adenomatous polyposis coli (APC) and beta-catenin genes play important roles in colorectal carcinogenesis. However, alteration of the components in the Wnt signaling pathway in colorectal cancer (CRC) with microsatellite instability (MSI) has been elucidated. To define the precise role of the Wnt signaling components in CRC and leukemia cell lines with MSI, mutational analyses of the T cell factor 4 (TCF4) genes were performed. Here we describe for the first time a TCF4 MSI+ phenotype in leukemia cell lines except in colon cancer cell lines. Moreover, we found that these cell lines exhibited deletion and insertion of 1-2A in an (A)9 repeat so as to result in (A)7, (A)8, (A)10 and (A)11 repeat, respectively. To characterize the cellular function of these special TCF4 mutant clones, transient transfection and fluorescent microscopy were analyzed and the results revealed that the TCF4 frameshift gene products all localized in nuclei. Surprisingly, these TCF4 frameshift mutants lost transcriptional activity with beta-catenin and down-regulate the target gene expression. These results delineate a novel role for MSI+TCF4 in leukemia and colon cancer progression.


Asunto(s)
Neoplasias del Colon/genética , Inestabilidad Genómica , Leucemia/genética , Repeticiones de Microsatélite , Factores de Transcripción TCF/genética , Línea Celular Tumoral , Neoplasias del Colon/patología , Humanos , Leucemia/patología , Mutación , Proteína 2 Similar al Factor de Transcripción 7 , Transcripción Genética , beta Catenina/genética , beta Catenina/fisiología
12.
Arch Toxicol ; 79(1): 1-6, 2005 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-15502967

RESUMEN

To understanding the reversible or irreversible harm to the beta-adrenergic system in the brain of lead-exposed rats, this study sets up an animal model to estimate the change in the sympathetic nervous system of brain after lead exposure was withdrawn. We address the following topics in this study: (a) the relationship between withdrawal time of lead exposure and brain beta-adrenergic receptor, blood lead level, and brain lead level in lead-exposed rats after lead exposure was stopped; and (b) the relationship between lead level and beta-adrenergic receptor and cyclic AMP (c-AMP) in brain. Wistar rats were chronically fed with 2% lead acetate and water for 2 months. Radioligand binding was assayed by a method that fulfilled strict criteria of beta-adrenergic receptor using the ligand [125I]iodocyanopindolol. The levels of lead were determined by electrothermal atomic absorption spectrometry. The c-AMP level was determined by radioimmunoassay. The results showed a close relationship between decreasing lead levels and increasing numbers of brain beta-adrenergic receptors and brain adenylate cyclase activity after lead exposure was withdrawn. The effect of lead exposure on the beta-adrenergic system of the brain is a partly reversible condition.


Asunto(s)
Adenilil Ciclasas/metabolismo , Encéfalo/metabolismo , Intoxicación por Plomo/metabolismo , Plomo/toxicidad , Receptores Adrenérgicos beta/metabolismo , Antagonistas Adrenérgicos beta/farmacología , Animales , Encéfalo/enzimología , AMP Cíclico/metabolismo , Modelos Animales de Enfermedad , Yodocianopindolol/farmacología , Plomo/farmacocinética , Intoxicación por Plomo/enzimología , Masculino , Radioinmunoensayo , Ratas , Ratas Wistar , Factores de Tiempo , Distribución Tisular
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