Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 46
Filtrar
Más filtros

Banco de datos
Tipo del documento
Intervalo de año de publicación
1.
J Biomed Sci ; 29(1): 29, 2022 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-35534851

RESUMEN

BACKGROUND: Castration-resistant prostate cancer (CRPC) with sustained androgen receptor (AR) signaling remains a critical clinical challenge, despite androgen depletion therapy. The Jumonji C-containing histone lysine demethylase family 4 (KDM4) members, KDM4A‒KDM4C, serve as critical coactivators of AR to promote tumor growth in prostate cancer and are candidate therapeutic targets to overcome AR mutations/alterations-mediated resistance in CRPC. METHODS: In this study, using a structure-based approach, we identified a natural product, myricetin, able to block the demethylation of histone 3 lysine 9 trimethylation by KDM4 members and evaluated its effects on CRPC. A structure-based screening was employed to search for a natural product that inhibited KDM4B. Inhibition kinetics of myricetin was determined. The cytotoxic effect of myricetin on various prostate cancer cells was evaluated. The combined effect of myricetin with enzalutamide, a second-generation AR inhibitor toward C4-2B, a CRPC cell line, was assessed. To improve bioavailability, myricetin encapsulated by poly lactic-co-glycolic acid (PLGA), the US food and drug administration (FDA)-approved material as drug carriers, was synthesized and its antitumor activity alone or with enzalutamide was evaluated using in vivo C4-2B xenografts. RESULTS: Myricetin was identified as a potent α-ketoglutarate-type inhibitor that blocks the demethylation activity by KDM4s and significantly reduced the proliferation of both androgen-dependent (LNCaP) and androgen-independent CRPC (CWR22Rv1 and C4-2B). A synergistic cytotoxic effect toward C4-2B was detected for the combination of myricetin and enzalutamide. PLGA-myricetin, enzalutamide, and the combined treatment showed significantly greater antitumor activity than that of the control group in the C4-2B xenograft model. Tumor growth was significantly lower for the combination treatment than for enzalutamide or myricetin treatment alone. CONCLUSIONS: These results suggest that myricetin is a pan-KDM4 inhibitor and exhibited potent cell cytotoxicity toward CRPC cells. Importantly, the combination of PLGA-encapsulated myricetin with enzalutamide is potentially effective for CRPC.


Asunto(s)
Antineoplásicos , Productos Biológicos , Flavonoides , Neoplasias de la Próstata Resistentes a la Castración , Andrógenos/farmacología , Andrógenos/uso terapéutico , Animales , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Productos Biológicos/farmacología , Productos Biológicos/uso terapéutico , Línea Celular Tumoral , Proliferación Celular , Resistencia a Antineoplásicos , Flavonoides/farmacología , Glicolatos , Glicoles/farmacología , Glicoles/uso terapéutico , Humanos , Histona Demetilasas con Dominio de Jumonji/genética , Histona Demetilasas con Dominio de Jumonji/farmacología , Masculino , Nitrilos/farmacología , Nitrilos/uso terapéutico , Neoplasias de la Próstata Resistentes a la Castración/tratamiento farmacológico , Neoplasias de la Próstata Resistentes a la Castración/genética , Neoplasias de la Próstata Resistentes a la Castración/metabolismo , Receptores Androgénicos/genética , Receptores Androgénicos/metabolismo , Receptores Androgénicos/uso terapéutico
2.
Entropy (Basel) ; 24(11)2022 Nov 13.
Artículo en Inglés | MEDLINE | ID: mdl-36421501

RESUMEN

Data representation has been one of the core topics in 3D graphics and pattern recognition in high-dimensional data. Although the high-resolution geometrical information of a physical object can be well preserved in the form of metrical data, e.g., point clouds/triangular meshes, from a regular data (e.g., image/audio) processing perspective, they also bring excessive noise in the course of feature abstraction and regression. For 3D face recognition, preceding attempts focus on treating the scan samples as signals laying on an underlying discrete surface (mesh) or morphable (statistic) models and by embedding auxiliary information, e.g., texture onto the regularized local planar structure to obtain a superior expressive performance to registration-based methods, but environmental variations such as posture/illumination will dissatisfy the integrity or uniform sampling condition, which holistic models generally rely on. In this paper, a geometric deep learning framework for face recognition is proposed, which merely requires the consumption of raw spatial coordinates. The non-uniformity and non-grid geometric transformations in the course of point cloud face scanning are mitigated by modeling each identity as a stochastic process. Individual face scans are considered realizations, yielding underlying inherent distributions under the appropriate assumption of ergodicity. To accomplish 3D facial recognition, we propose a windowed solid harmonic scattering transform on point cloud face scans to extract the invariant coefficients so that unrelated variations can be encoded into certain components of the scattering domain. With these constructions, a sparse learning network as the semi-supervised classification backbone network can work on reducing intraclass variability. Our framework obtained superior performance to current competing methods; without excluding any fragmentary or severely deformed samples, the rank-1 recognition rate (RR1) achieved was 99.84% on the Face Recognition Grand Challenge (FRGC) v2.0 dataset and 99.90% on the Bosphorus dataset.

3.
Biochem Biophys Res Commun ; 527(1): 283-288, 2020 06 18.
Artículo en Inglés | MEDLINE | ID: mdl-32446381

RESUMEN

Lysyl oxidase (LOX) is involved in fibrosis by catalyzing collagen cross-linking. Previous work observed that Triptolide (TPL) alleviated radiation-induced pulmonary fibrosis (RIPF), but it is unknown whether the anti-RIPF effect of TPL is related to LOX. In a mouse model of RIPF, we found that LOX persistently increased in RIPF which was significantly lowered by TPL. Excessive LOX aggravated fibrotic lesions in RIPF, while LOX inhibition mitigated RIPF. Irradiation enhanced the transcription and synthesis of LOX by lung fibroblasts through IKKß/NFκB activation, and siRNA knockdown IKKß largely abolished LOX production. By interfering radiation induced IKKß activation, TPL prevented NFκB nuclear translocation and DNA binding, and potently decreased LOX synthesis. Our results demonstrate that the anti-RIPF effect of TPL is associated with reduction of LOX production which mediated by inhibition of IKKß/NFκB pathway.


Asunto(s)
Diterpenos/farmacología , Proteínas de la Matriz Extracelular/antagonistas & inhibidores , Quinasa I-kappa B/antagonistas & inhibidores , Fenantrenos/farmacología , Proteína-Lisina 6-Oxidasa/antagonistas & inhibidores , Fibrosis Pulmonar/tratamiento farmacológico , Traumatismos por Radiación/tratamiento farmacológico , Animales , Diterpenos/administración & dosificación , Relación Dosis-Respuesta a Droga , Compuestos Epoxi/administración & dosificación , Compuestos Epoxi/farmacología , Proteínas de la Matriz Extracelular/biosíntesis , Femenino , Quinasa I-kappa B/metabolismo , Inyecciones Intravenosas , Ratones , Ratones Endogámicos C57BL , Estructura Molecular , Fenantrenos/administración & dosificación , Proteína-Lisina 6-Oxidasa/biosíntesis , Fibrosis Pulmonar/metabolismo , Traumatismos por Radiación/metabolismo , Relación Estructura-Actividad
4.
Langmuir ; 34(4): 1441-1446, 2018 01 30.
Artículo en Inglés | MEDLINE | ID: mdl-29307176

RESUMEN

The adsorption of methyl red (MR) isomers (ortho, meta, and para) on metal-organic frameworks (MOFs) was investigated by using a fluorescence quenching technique. All three MR isomers were found to quench the fluorescence of MOFs effectively. Nonlinear fluorescence quenching trends were observed in Stern-Volmer plots. A modified nonlinear Stern-Volmer equation with the concepts of multiple adsorption sites, adsorption strength, and quencher accessibility was successfully adopted to fit the fluorescence quenching data. The fitted parameters were correlated with the structural properties of MRs and MOFs. The order of quenching efficiency was found to be m-MR > p-MR > o-MR for all MOFs. This indicates that MR molecules not only adsorb via carboxylate-metal bonding but also adsorb through π-π interactions between the aromatic rings of MR and linker molecules in MOFs. The position of the carboxylate group in MRs and the structure of the linkers in MOFs are the key factors affecting the fluorescence quenching efficiency.

5.
Bioorg Med Chem ; 24(18): 4263-4271, 2016 09 15.
Artículo en Inglés | MEDLINE | ID: mdl-27448774

RESUMEN

In an effort to develop new drug candidates with enhanced anticancer activity, our team synthesized and assessed the cytotoxicity of a series of novel xanthone derivatives with two longer 3,6-disubstituted amine carbonyl methoxy side chains on either benzene ring in selected human cancer cell lines. An MTT assay revealed that a set of compounds with lower IC50 values than the positive control, 5-FU, exhibited greater anticancer effects. The most potent derivative (XD8) exhibited anticancer activity in MDA-MB-231, PC-3, A549, AsPC-1, and HCT116 cells lines with IC50 values of 8.06, 6.18, 4.59, 4.76, and 6.09µM, respectively. Cell cycle analysis and apoptosis activation suggested that the mechanism of action of these derivatives includes cell cycle regulation and apoptosis induction.


Asunto(s)
Antineoplásicos/farmacología , Xantonas/farmacología , Antineoplásicos/síntesis química , Apoptosis/efectos de los fármacos , Caspasa 3/metabolismo , Caspasa 7/metabolismo , Línea Celular Tumoral , Ensayos de Selección de Medicamentos Antitumorales , Puntos de Control de la Fase G1 del Ciclo Celular/efectos de los fármacos , Puntos de Control de la Fase G2 del Ciclo Celular/efectos de los fármacos , Humanos , Relación Estructura-Actividad , Xantonas/síntesis química
6.
Adv Exp Med Biol ; 812: 149-155, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24729227

RESUMEN

The tumor vascular system, which is critical to the survival and growth of solid tumors, has been an attractive target for anticancer research. Building on studies that show that some flavonoids have anticancer vascular effects, we developed and analyzed the flavonoid derivative R24 [3, 6-bis (2-oxiranylmethoxy)-9H-xanthen-9-one]. A CAM assay revealed that R24 disrupted neovascular formation; fewer dendrites were detected and overall dendritic length was shorter in the R24-treated chicken embryos. The antiproliferative effect of R24 was measured by MTT assay in A549 (lung cancer), AsPC-1 (pancreatic cancer), HCT-116 (colorectal cancer), and PC-3 (prostate cancer) cell lines. R24 reduced proliferation with an IC50 of 3.44, 3.59, 1.22, and 11.83 µM, respectively. Cell-cycle analysis and Annexin-V/propidium iodide staining showed that R24 induced apoptosis. In addition, R24 regulated intracellular ROS production in a dose-dependent manner. CM-H2DCFDA staining indicated that intracellular ROS production increased with the R24 dose. In summary, we found that R24 exhibits potent antiangiogenic and antiproliferative effects, induces apoptosis, and promotes ROS production.


Asunto(s)
Flavonoides/farmacología , Neoplasias/irrigación sanguínea , Neovascularización Patológica/prevención & control , Especies Reactivas de Oxígeno/metabolismo , Línea Celular Tumoral , Humanos
7.
Adv Exp Med Biol ; 765: 47-53, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-22879013

RESUMEN

In this study, we compared two in vitro collagen production assays ([(3)H]-proline incorporation and Sirius Red) for their ability to determine the pattern shift from soluble to deposited collagen. The effect of the antifibrotic agent, triptolide (TPL), on collagen production was also studied. The results showed that: (1) 48 h after NIH 3T3 (murine embryo fibroblast) and HFL-1(human fetal lung fibroblast) were exposed to transforming growth factor-beta 1 (TGF-ß), there was an increase in soluble collagen in the culture medium; (2) on day 4, soluble collagen declined, whereas deposited collagen increased; (3) Sirius Red was easier to use than [(3)H]-proline incorporation and more consistently reflected the collagen pattern shift from soluble to deposited; (4) the in vitro Sirius Red assay took less time than the in vivo assay to determine the effect of TPL. Our results suggest that: (a) the newly synthesized soluble collagen can sensitively evaluate an agent's capacity for collagen production and (b) Sirius Red is more useful than [(3)H]-proline because it is easier to use, more convenient, less time consuming, and does not require radioactive material.


Asunto(s)
Compuestos Azo , Bioensayo , Colágeno/metabolismo , Embrión de Mamíferos/metabolismo , Feto/metabolismo , Fibroblastos/metabolismo , Pulmón/metabolismo , Animales , Antineoplásicos Alquilantes/farmacología , Células Cultivadas , Colorantes , Diterpenos/farmacología , Embrión de Mamíferos/citología , Embrión de Mamíferos/efectos de los fármacos , Compuestos Epoxi/farmacología , Feto/citología , Feto/efectos de los fármacos , Fibroblastos/citología , Fibroblastos/efectos de los fármacos , Humanos , Pulmón/citología , Pulmón/efectos de los fármacos , Ratones , Células 3T3 NIH , Fenantrenos/farmacología , Prolina/metabolismo , Factor de Crecimiento Transformador beta/farmacología
8.
Adv Exp Med Biol ; 765: 147-153, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-22879027

RESUMEN

Although glycoproteins possess a variety of functional and structural roles in intracellular and intercellular activities, the effect of ionizing radiation (IR) on glycosylation is largely unknown. To explore this effect, we established a sandwich assay in which PHA-L, a phytohaemagglutinin that agglutinates leukocytes, was used as a coating layer to capture glycoproteins containing complex oligosaccharides; the bound glycoproteins were then measured. C57BL/6 mice were exposed to 0, 3, 6, or 10 Gy, and the plasma was collected at 6, 12, 18, 24, 48, 72, or 168 h and then analyzed for galactose/N-acetylgalactosamine (Gal/GalNAc) containing proteins. We found that (1) the sandwich assay accurately measured the level of glycoproteins, (2) 6-12 h after IR, the amount of glycoproteins containing GalNAc increased, and (3) at 72 and 168 h, 10 Gy was associated with a decrease in Gal/GalNAc. These IR-induced alterations might relate to the release of glycoproteins into the blood and the damage of the proteins and genes that are related to the glycosylation process.


Asunto(s)
Acetilgalactosamina/sangre , Galactosa/sangre , Glicoproteínas/sangre , Glicosilación/efectos de la radiación , Manosa/sangre , Irradiación Corporal Total , Acetilgalactosamina/análogos & derivados , Animales , Ensayo de Inmunoadsorción Enzimática , Masculino , Ratones , Ratones Endogámicos C57BL , Fitohemaglutininas/metabolismo
9.
Adv Exp Med Biol ; 765: 155-161, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-22879028

RESUMEN

Various members of the fibroblast growth factor (FGF) family mitigate radiation-induced damage. We designed and synthesized the binding domain peptide of FGF-2 (FGF-P) with a dimer form resistant to peptidase and examined its mitigatory effect on murine bone marrow cells. NIH Swiss mice were exposed to different doses of total body irradiation (TBI) and treated with ten doses of 5 mg/kg FGF-P. We achieved the following results: (1) FGF-P stimulated the growth of bone marrow cells harvested from mice exposed to 3 Gy; (2) on day 25 after 6 Gy TBI, the number of leukocytes and granulocytes was higher in the FGF-P group than in the vehicle-alone group; (3) FGF-P significantly increased the number of pro-B and pre-B cells; and (4) FGF-P treatment in vivo increased the long-term hematopoietic stem cells (LT-HSC) in bone marrow. These data reveal the underlying mechanism by which FGF-P rescued a significant percentage of the exposed mice. The increase of LT-HSC in bone marrow leads to a concomitant increase of pro-B and pre-B cells followed by leukocytes and granulocytes, which in turn enhance immunity against infection.


Asunto(s)
Linfocitos B/efectos de los fármacos , Médula Ósea/efectos de los fármacos , Médula Ósea/efectos de la radiación , Factores de Crecimiento de Fibroblastos/farmacología , Células Madre Hematopoyéticas/efectos de los fármacos , Fragmentos de Péptidos/farmacología , Irradiación Corporal Total , Animales , Linfocitos B/patología , Linfocitos B/efectos de la radiación , Médula Ósea/patología , Células Cultivadas , Células Madre Hematopoyéticas/patología , Células Madre Hematopoyéticas/efectos de la radiación , Masculino , Ratones
10.
Adv Exp Med Biol ; 765: 335-341, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-22879053

RESUMEN

Inflammatory molecules (IMs) play an important role in ionizing radiation (IR)-induced soft tissue damage. The alteration of IMs as a function of time was studied with a protein array containing 62 IMs in mouse cutaneous soft tissues exposed to 30 Gy. The results showed that: (1) 2 days after irradiation, the levels of TGF-ß1, MIP-1γ, IL-1α, and sTNF RI increased, while IGFBP-3, CXCL16, and IL-1ß decreased in IR skin as compared to control skin; (2) 21 days after IR, TGF-ß1, and MIP-1 γ, IL-1α remained high, while CXCL16 and IL-1ß remained low; (3) 3 months after IR, the cytokine pattern exhibited reversals. The levels of MIP-1γ decreased, while VCAM-1, IGFBP-3, and TGF-ß1 production increased. The data indicated that: (a) IMs change as a function of time after soft tissue irradiation; (b) changing IM levels may reflect the altered balance of the cytokine network, leading to imbalance or homeostasis; and (c) an antibody-based protein array can be used to assess multiple IMs simultaneously, making it useful for bulk screening for changes in tissue cytokine levels.


Asunto(s)
Miembro Posterior/metabolismo , Miembro Posterior/efectos de la radiación , Mediadores de Inflamación/metabolismo , Piel/metabolismo , Piel/efectos de la radiación , Traumatismos de los Tejidos Blandos/metabolismo , Traumatismos de los Tejidos Blandos/patología , Animales , Quimiocinas/metabolismo , Citocinas/metabolismo , Femenino , Miembro Posterior/inmunología , Péptidos y Proteínas de Señalización Intercelular/metabolismo , Ratones , Ratones Endogámicos C57BL , Análisis por Matrices de Proteínas , Piel/inmunología , Factores de Tiempo
11.
Adv Exp Med Biol ; 789: 195-201, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23852495

RESUMEN

Amifostine is a first-line cytoprotective drug used to prevent radiotherapy-induced or chemotherapy-induced injuries. However, its mechanism of action is not well understood. In this study, freshly harvested bone marrow cells were treated with amifostine and analyzed with a series of mitochondrial indices. In vitro results showed that bone marrow cells treated with amifostine 0.5 h before irradiation (0.5 Gy) experienced several benefits, as compared to vehicle controls, including (1) reduced reactive oxygen species levels, which reduced the production of free radicals; (2) better preservation of mitochondria, as indicated by MitoTracker-positive staining and the increased intensity of staining; (3) reduced apoptosis, as demonstrated by Annexin V staining; and (4) a better proliferation rate, as illustrated by MTT assay. Our in vitro studies showed that amifostine-treated mice exhibited (1) higher ATP production; (2) reduced plasma IL-2 levels, suppressing the immune response triggered by radiotoxicity; and (3) enhanced radiation-induced production of granulocyte colony-stimulating factor. All of these processes benefit recovery from radiation-induced damage.


Asunto(s)
Amifostina/farmacología , Células de la Médula Ósea/efectos de los fármacos , Médula Ósea/efectos de los fármacos , Citocinas/metabolismo , Mitocondrias/efectos de los fármacos , Protectores contra Radiación/farmacología , Adaptación Fisiológica/efectos de los fármacos , Adenosina Trifosfato/metabolismo , Animales , Médula Ósea/crecimiento & desarrollo , Médula Ósea/metabolismo , Células de la Médula Ósea/metabolismo , Masculino , Ratones , Mitocondrias/metabolismo , Especies Reactivas de Oxígeno/metabolismo
12.
Adv Exp Med Biol ; 765: 371-377, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-22879058

RESUMEN

Mitochondrial DNA (mtDNA) is maternally inherited and controls the oxygen-related production of adenosine-5'-triphosphate, which is transported from the mitochondria to other cellular compartments and used as energy for cellular activities. The mtDNA is physically separated from nuclear DNA (nDNA). Ionizing radiation (IR) causes the release of both mtDNA and nDNA into circulation. Our previous study demonstrated that nDNA has potential to be a biodosimeter. In this study, branched DNA technology was used to explore the alteration pattern of mtDNA after IR. C57BL/6 mice were exposed to 0, 1.5, 3, 6, 8, or 10 Gy total body irradiation; thereafter, plasma mtDNA was assessed with samples collected at 3, 6, 9, 15, 24, 48, 72, or 168 h. We found that: (1) the designed probesets were specific for mtDNA extracted from the liver, and they recognized the small amount of mtDNA mixed in the nDNA; (2) plasma mtDNA exhibited a statistically significant increase only at 6 h after 8 Gy irradiation. The alteration of mtDNA was not dose-dependent or time-dependent; hence, it is unlikely to be an effective biodosimeter.


Asunto(s)
Núcleo Celular/genética , Núcleo Celular/efectos de la radiación , ADN Mitocondrial/sangre , ADN Mitocondrial/genética , Traumatismos por Radiación/diagnóstico , Irradiación Corporal Total , Animales , Masculino , Ratones , Ratones Endogámicos C57BL , Dosis de Radiación , Traumatismos por Radiación/sangre , Traumatismos por Radiación/genética , Factores de Tiempo
13.
Adv Exp Med Biol ; 789: 257-264, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23852503

RESUMEN

Interleukin 11 (IL-11) is a multifunctional cytokine isolated from bone marrow (BM)-derived stromal cells that promotes hematopoiesis and prolongs the life span of lethally irradiated animals. However, the underlying mechanism for the protective effect of IL-11 on BM is unclear. In this study, we explored the effect of IL-11 on irradiated BM cells. Freshly harvested BM cells were pretreated with 20 ng/ml of recombinant IL-11 for 30 min, irradiated with a dose of 0.5 Gy, cultured for 24 h, and then subjected to several assays. In vitro data showed that, as compared to the vehicle controls, IL-11: (1) reduced the production of reactive oxygen species; (2) reduced the alteration of mitochondrial membrane potential; (3) increased MitoTracker staining, suggesting that the number of mitochondria and their functions were better maintained; and (4) reduced apoptosis of BM cells and enhanced BM cell proliferation. In vivo studies of mice pretreated with saline or 100 µg/kg of IL-11 at 12 and 2 h before 10-Gy total body irradiation (TBI) demonstrated that G-CSF and IL-6 were significantly upregulated, whereas IL-2 and IL-4 were reduced. We found that IL-11 protects mitochondrial functions, acts with G-CSF and IL-6 to stimulate the growth of radiation-damaged BM, and reduces the immune response to radiation injury.


Asunto(s)
Médula Ósea/efectos de los fármacos , Médula Ósea/efectos de la radiación , Interleucina-11/farmacología , Mitocondrias/efectos de los fármacos , Mitocondrias/efectos de la radiación , Traumatismos Experimentales por Radiación/metabolismo , Traumatismos Experimentales por Radiación/prevención & control , Animales , Apoptosis/efectos de los fármacos , Apoptosis/efectos de la radiación , Médula Ósea/metabolismo , Células de la Médula Ósea/metabolismo , Células de la Médula Ósea/efectos de la radiación , Procesos de Crecimiento Celular/efectos de los fármacos , Procesos de Crecimiento Celular/efectos de la radiación , Factor Estimulante de Colonias de Granulocitos/metabolismo , Interleucina-11/metabolismo , Interleucina-6/metabolismo , Masculino , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Potencial de la Membrana Mitocondrial/efectos de la radiación , Ratones , Mitocondrias/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Irradiación Corporal Total/métodos
14.
Adv Exp Med Biol ; 789: 273-280, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23852505

RESUMEN

In this study, we investigated the response of irradiated bone marrow cells to granulocyte colony-stimulating factor (G-CSF). Freshly harvested bone marrow cells were treated with either saline (vehicle control) or 20 ng/ml of G-CSF. Thereafter, cells were separated into nonirradiated (no-IR) and irradiated (IR, 0.5 Gy) groups. IR cells exhibited a higher proliferation rate in response to G-CSF, as compared to the no-IR cells. Reduced levels of reactive oxygen species indicated that G-CSF-treated IR cells produced fewer free radicals, as compared to the no-IR cells. The G-CSF-treated IR cells also had a lower apoptotic rate than their no-IR counterparts. Furthermore, G-CSF-treated IR cells exhibited less alteration of mitochondrial membrane potential, as compared to the no-IR cells. Finally, the mitochondrial number increased in the G-CSF-treated IR cells. The radiation-induced increase in plasma IL-6 in vivo could be enhanced by the administration of G-CSF. The data suggest that radiation potentiates the response of bone marrow cells to G-CSF treatment.


Asunto(s)
Médula Ósea/efectos de los fármacos , Médula Ósea/efectos de la radiación , Factor Estimulante de Colonias de Granulocitos/farmacología , Animales , Médula Ósea/metabolismo , Células de la Médula Ósea/efectos de los fármacos , Células de la Médula Ósea/metabolismo , Células de la Médula Ósea/efectos de la radiación , Radicales Libres/metabolismo , Interleucina-6/sangre , Masculino , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Potencial de la Membrana Mitocondrial/efectos de la radiación , Ratones , Mitocondrias/efectos de los fármacos , Mitocondrias/metabolismo , Mitocondrias/efectos de la radiación , Especies Reactivas de Oxígeno/metabolismo
15.
Cytokine ; 58(2): 169-77, 2012 May.
Artículo en Inglés | MEDLINE | ID: mdl-22277799

RESUMEN

PURPOSE: To determine the plasma concentrations of acute responding cytokines/chemokines following 9-Gy ionizing radiation in C57BL/6 (radiation tolerant) and C3H/HeN (radiation sensitive) murine strains. METHODS AND MATERIALS: Mice (5/group) received 9-Gy total body irradiation (TBI), and the plasma from each mouse was collected at 6h or 1, 2, 4, or 10 days after TBI. A multiplex bead array was used to assess the levels of 32 cytokines/chemokines in plasma to determine their common and strain-specific temporal responses. RESULTS: The plasma levels of five cytokines/chemokines (Axl, FasL, ICAM-1, TARC, and TSLP) were beyond the detectable level. Five (VEGF, IL-2, IL-5, IL-17, and CD30) were unaffected by irradiation in either strain. Temporal patterns were similar in both murine strains for 10 of the cytokines tested, including G-CSF, IL-6, TCA-3, MCP-1, MIP-1γ, KC, CXCL 13, CXCL 16, MDC, and TIMP-1; the other 12 molecules (GM-CSF, IL-3, SCF, IL-1ß, IL-4, IL-10, IL-12p70, MIP-1α, Eotaxin, TNF-α, sTNF-R1, and CD40) showed strain-specific response patterns. While a number of cytokines had temporal response patterns following TBI, the strains exhibited quantitatively different results. CONCLUSIONS: The levels of 27 of the 32 plasma cytokines measured indicate the following: (1) different cytokine concentrations and temporal patterns in the two strains may partly explain different radiation sensitivities and sequelae following irradiation; (2) many of the cytokines/chemokines exhibit similar temporal responses in the two strains. These responses suggest the potential value of using a panel of cytokine/chemokine temporal patterns for radiation dosimetry. Although radiation doses will be difficult to quantitate due to the large variation in levels and temporal responses exhibited in the two murine strains, serial measurements of cytokines might help identify subjects exposed to radiation.


Asunto(s)
Quimiocinas/metabolismo , Citocinas/metabolismo , Irradiación Corporal Total , Animales , Masculino , Ratones , Ratones Endogámicos C3H , Ratones Endogámicos C57BL
16.
Adv Exp Med Biol ; 701: 291-7, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21445800

RESUMEN

Fifty-eight semicarbazone and pyrazole derivatives of curcumin have been developed as potential mitigation agents to treat acute radiation syndrome (ARS). Pyridyl (D12, D13), furyl (D56), and phenyl (D68) derivatives of curcumin semi-carbazones were found to provide the highest dose modifying factors (DMF) with respect to survival in sub-TBI (bone marrow sparing) exposures in mouse models. To investigate the basis for the mitigating effects of these agents on ARS, we examined their oxidation potentials and radical scavenging properties in comparison to other semicarbazone and pyrazole curcumin derivatives with less effective DMFs. Comparisons between D12, D13, D56, and D68 and other semicarbazone and pyrazole derivatives of curcumin did not show a sufficient difference in reducing properties and hydrogen atom donating properties for these properties to be the basis of the dose modifying activities of these compounds. Therefore, their DMFs likely reflect structure-activity relationship(s),wherein interaction with key receptors or alteration of enzyme expression result in modifications of cellular or tissue responses to radiation, rather than on the derivatives' ability to modify radiation-induced flux of free radicals through direct interaction with these radicals.


Asunto(s)
Antioxidantes/farmacología , Curcumina/análogos & derivados , Curcumina/farmacología , Pirazoles/química , Protectores contra Radiación/farmacología , Semicarbazonas/química , Animales , Depuradores de Radicales Libres/farmacología , Radicales Libres/metabolismo , Ratones , Ratones Endogámicos BALB C , Molibdeno/metabolismo , Oxidación-Reducción , Ácidos Fosfóricos/metabolismo , Relación Estructura-Actividad , Irradiación Corporal Total
17.
Adv Exp Med Biol ; 701: 283-9, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21445799

RESUMEN

UNLABELLED: Quercetin, a plant-derived aglycone form of flavonoid glycosides, has been used as a nutritional supplement and may be beneficial against a variety of diseases, including cancer. We examined the antioxidant properties of quercetin. The reduction potential of quercetin was measured at various pH values using voltammetric methods, and its total antioxidant capacity (TAC) was measured using the phosphomolybdenum method. The effect of quercetin on production of reactive oxygen species (ROS) and nitric oxide (NO) in LPS-stimulated human THP-1 acute monocytic leukemia cells was determined by flow cytometry using CM-H2DCFDA dye. The results were compared with curcumin, a natural product exhibiting a similar range of reported health benefits. RESULTS: 1) Quercetin has a higher reduction potential compared with curcumin at three different pH settings and is comparable to Trolox at pH 7-9.5; 2) its TAC is 3.5 fold higher than curcumin; 3) it reduced LPS-induced ROS to near normal levels; 4) it reduced LPS-induced NO production. These data provide a physico-chemical basis for comparing antioxidants, with potential benefits individually or in combination.


Asunto(s)
Antioxidantes/farmacología , Leucemia Monocítica Aguda/tratamiento farmacológico , Mitocondrias/efectos de los fármacos , Quercetina/farmacología , Antineoplásicos/farmacología , Curcumina/farmacología , Citometría de Flujo , Humanos , Leucemia Monocítica Aguda/metabolismo , Lipopolisacáridos/farmacología , Mitocondrias/metabolismo , Óxido Nítrico/metabolismo , Oxidación-Reducción , Especies Reactivas de Oxígeno/metabolismo , Células Tumorales Cultivadas
18.
Adv Exp Med Biol ; 645: 43-8, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19227448

RESUMEN

The effect of radiation on the mitochondrial genome in vivo is largely unknown. Though mitochondrial DNA (mtDNA) is vital for cellular survival and proliferation, it has little DNA repair machinery compared with nuclear DNA (nDNA). A better understanding of how radiation affects mtDNA should lead to new approaches for radiation protection. We have developed a new system using real-time PCR that sensitively detects the change in copy number of mtDNA compared with nDNA. In each sample, the DNA sequence coding 18S rRNA served as the nDNA reference in a run simultaneously with a mtDNA sequence. Small bowel collected 24 hours after 2 Gy or 4 Gy total body irradiation (TBI) exhibited increased levels of mtDNA compared with control mice. A 4 Gy dose produced a greater effect than 2 Gy. Similarly, in bone marrow collected 24 hours after 4 Gy or 7 Gy TBI, 7 Gy produced a greater response than 4 Gy. As a function of time, a greater effect was seen at 48 hours compared with 24 hours. In conclusion, we found that radiation increased the ratio of mtDNA:nDNA and that this effect seems to be tissue independent and seems to increase with radiation dose and duration following radiation exposure.


Asunto(s)
ADN Mitocondrial/genética , Intestino Delgado/metabolismo , Intestino Delgado/efectos de la radiación , Mitocondrias/efectos de los fármacos , Animales , Dosificación de Gen/genética , Masculino , Ratones , Ratones Endogámicos BALB C , Reacción en Cadena de la Polimerasa , Factores de Tiempo
19.
Clin Cancer Res ; 13(16): 4891-9, 2007 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-17699869

RESUMEN

PURPOSE: The lack of effective treatment for pancreatic cancer results in a very low survival rate. This study explores the enhancement of the therapeutic effect on human pancreatic cancer via the combination of triptolide and ionizing radiation (IR). EXPERIMENTAL DESIGN: In vitro AsPC-1 human pancreatic cancer cells were treated with triptolide alone, IR alone, or triptolide plus IR. Cell proliferation was analyzed with sulforhodamine B (SRB) method and clonogenic survival; comparison of apoptosis induced by the above treatment was analyzed by annexin V-propidium iodide (PI) staining. Furthermore, the expression of apoptotic pathway intermediates was measured by the assay of caspase activity and Western blot. Mitochondrial transmembrane potential was determined by JC-1 assay. In vivo, AsPC-1 xenografts were treated with 0.25 mg/kg triptolide, 10 Gy IR, or triptolide plus IR. The tumors were measured for volume and weight at the end of the experiment. Tumor tissues were tested for terminal nucleotidyl transferase-mediated nick end labeling (TUNEL) and immunohistochemistry. RESULTS: The combination of triptolide plus IR reduced cell survival to 21% and enhanced apoptosis, compared with single treatment. In vivo, tumor growth of AsPC-1 xenografts was reduced further in the group treated with triptolide plus IR compared with single treatment. TUNEL and immunohistochemistry of caspase-3 cleavage in tumor tissues indicated that the combination of triptolide plus IR resulted in significantly enhanced apoptosis compared with single treatments. CONCLUSIONS: Triptolide in combination with ionizing radiation produced synergistic antitumor effects on pancreatic cancer both in vitro and in vivo and seems promising in the combined modality therapy of pancreatic cancer.


Asunto(s)
Antineoplásicos Alquilantes/farmacología , Diterpenos/farmacología , Neoplasias Pancreáticas/terapia , Fenantrenos/farmacología , Animales , Apoptosis/efectos de los fármacos , Apoptosis/efectos de la radiación , Línea Celular Tumoral , Terapia Combinada , Compuestos Epoxi/farmacología , Fase G2/efectos de los fármacos , Fase G2/efectos de la radiación , Humanos , Ratones , Ratones Desnudos , Trasplante de Neoplasias , Neoplasias Pancreáticas/radioterapia , Trasplante Heterólogo
20.
Adv Exp Med Biol ; 614: 179-86, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18290328

RESUMEN

Resveratrol, a phytoalexin found in the skin of grapes, is believed to have multiple bioactivities including anti-cancer, anti-carcinogenesis and antiinflammatory. The mechanisms by which resveratrol might produce these effects are not well understood. In this study, malignant human pancreatic cancer cells were treated without or with resveratrol in combination with ionizing radiation (IR), and then the mitochondrial function of treated cells was evaluated using several standardized assays. They include the Calcein AM method for mitochondria transition pore; the JC-1 staining method for mitochondria membrane potential; the CM-H2DCFDA method for reactive oxygen species; and the Annexin V/propidium iodide (PI) method for apoptosis/cell death. Our results indicated that (1) pore function was partially intact after resveratrol, but resveratrol probably interfered with the accumulation of intracellular Calcein AM; (2) depolarization of the mitochondria membrane was increased in the resveratrol treated cells, consistent with mitochondrial dysfunction; (3) ROS was slightly increased with resveratrol, a phenomenon that was greatly increased when this agent was combined with IR; and (4) in parallel with the above changes in mitochondrial and drug transport, cells treated with resveratrol showed increased apoptosis as measured by Annexin V/PI staining. In summary, the anti-cancer effect of resveratrol is associated with the damage of mitochondrial function that leads to increased ROS, apoptosis, and possibly intracellular drug accumulation via inhibition of proteins involved in multi-drug resistance (MDR).


Asunto(s)
Anticarcinógenos/farmacología , Apoptosis/efectos de los fármacos , Mitocondrias/metabolismo , Estilbenos/farmacología , Apoptosis/fisiología , Bencimidazoles/metabolismo , Carbocianinas/metabolismo , Muerte Celular/efectos de los fármacos , Línea Celular Tumoral , Relación Dosis-Respuesta a Droga , Fluoresceínas/análisis , Fluoresceínas/metabolismo , Colorantes Fluorescentes , Humanos , Potenciales de la Membrana/efectos de los fármacos , Membranas Mitocondriales/efectos de los fármacos , Membranas Mitocondriales/metabolismo , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/patología , Especies Reactivas de Oxígeno/análisis , Especies Reactivas de Oxígeno/metabolismo , Resveratrol
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA