Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 39
Filtrar
Más filtros










Intervalo de año de publicación
1.
J Mol Neurosci ; 68(4): 590-602, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31054091

RESUMEN

Erythropoietin, a multitarget molecule exhibited neuroprotective properties, especially against cerebral ischemia. However, little effort has been made to determinate both the administration pathway and doses that diminishes neuronal damage. In this study, we investigate the effect on CA1 region of different intranasal doses of rHuEPO (500, 1000 and 2500 IU/kg) applied in distinct post-damage times (1, 6, and 24 h) against ischemic cellular damage. Furthermore, most effective dose and time were used to evaluate gen and protein expression changes in 3 key molecules (EPO, EPOR, and ßcR). We established that CA1-region present histopathological damage in this ischemia model and that rHuEPO protects cells against damage, particularly at 1000 IU dose. Molecular data shows that EPO and EPOR gene expression are upregulated in a short term after damage treatment with rHuEPO (1 h); oppositely, BcR is upregulated in ischemic and Isc + EPO. Protein expression data displays no changes on EPO expression in evaluated times after treatment, but a tendency to increase 24 h after damage; in the opposite way, EPOR is upregulated significantly 6 h after treatment and this effect last until 24 h. So, our data suggest that a single intranasal dose of rHuEPO (1 h post-injury) provides histological neurorestoration in CA1 hippocampal region, even if we did not observe a dose-dependent dose effect, the medium dose evaluated (1000 UI/kg of b.w.) was more effective and sufficient for induces molecular changes that provides a platform for neuroprotection.


Asunto(s)
Isquemia Encefálica/tratamiento farmacológico , Región CA1 Hipocampal/efectos de los fármacos , Eritropoyetina/uso terapéutico , Fármacos Neuroprotectores/uso terapéutico , Administración Intranasal , Animales , Región CA1 Hipocampal/metabolismo , Eritropoyetina/administración & dosificación , Eritropoyetina/farmacología , Humanos , Masculino , Fármacos Neuroprotectores/administración & dosificación , Fármacos Neuroprotectores/farmacología , Ratas , Ratas Wistar
2.
Clin Exp Immunol ; 130(1): 140-9, 2002 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-12296865

RESUMEN

The aim of the study was to determine whether collagen-polyvinylpyrrolidone (collagen-PVP) modifies some proinflammatory responses in synovium cultures from rheumatoid arthritis (RA) patients. Synovium from 10 RA patients were cultured with or without 1% collagen-PVP. Tissues on the 3rd, 5th and 7th culture day were sectioned and stained by the Herovici technique. Total collagen and type I/III collagen ratios were evaluated by the Woessner micromethod and by interrupted gel electrophoresis, respectively. Collagenolytic activity was assessed by degradation of [3H]-collagen in supernatants. TIMP-1, IL-1beta and TNF-alpha were determined in supernatants by ELISA, and the results were normalized by DNA concentration. IL-1beta, TNF-alpha, IL-6, IL-8, MMP-1, TIMP-1, Cox-1, VCAM-1, ICAM-1 and Fas/APO95 expression was evaluated by immunohistochemistry. Apoptosis was detected by TUNEL technique. The histological analysis and electrophoresis revealed a 1.7-fold increase of type III collagen in a time-dependent fashion in collagen-PVP-treated cultures. Proinflammatory cytokines (IL-1beta: 58 +/- 9 versus 22 +/- 10; TNF-alpha: 41 +/- 6 versus 11 +/- 3; IL-8: 59 +/- 12 versus 29 +/- 9; treated versus untreated), adhesion molecule (ICAM-1: 57 +/- 11 versus 29 +/- 15; VCAM-1: 49 +/- 7 versus 21 +/- 13; treated versus untreated) as well as Cox-1 (59 +/- 10 versus 20 +/- 3) expression was down-regulated in RA synovium treated. Meanwhile, TIMP-1 (36 +/- 7 versus 57 +/- 11) and Fas expression (20 +/- 10 versus 55 +/- 13) and apoptosis (14 +/- 3 versus 55 +/- 5) were up-regulated in treated cultures compared with controls. In supernatants, the collagenolytic activity, as well as IL-1beta and TNF-alpha, levels were all down-regulated in treated cultures (two, three, fourfold, respectively). The addition of collagen-PVP to synovium-induced down-modulation of some inflammatory parameters and an increase in apoptosis of synovial cells. Perhaps this mechanism could contribute to inhibit outgrowth of pannus formation and to down-regulate inflammation of joints in patients with RA.


Asunto(s)
Apoptosis/efectos de los fármacos , Artritis Reumatoide/metabolismo , Enfermedades Autoinmunes/metabolismo , Colágeno/farmacología , Regulación de la Expresión Génica/efectos de los fármacos , Mediadores de Inflamación/metabolismo , Povidona/farmacología , Membrana Sinovial/efectos de los fármacos , Adulto , Anciano , Apoptosis/fisiología , Artritis Reumatoide/patología , Enfermedades Autoinmunes/patología , Moléculas de Adhesión Celular/biosíntesis , Moléculas de Adhesión Celular/genética , Ciclooxigenasa 1 , Citocinas/biosíntesis , Citocinas/genética , Inducción Enzimática/efectos de los fármacos , Proteína Ligando Fas , Femenino , Humanos , Interleucinas/biosíntesis , Interleucinas/genética , Isoenzimas/biosíntesis , Isoenzimas/genética , Masculino , Metaloproteinasa 1 de la Matriz/biosíntesis , Metaloproteinasa 1 de la Matriz/genética , Glicoproteínas de Membrana/biosíntesis , Glicoproteínas de Membrana/genética , Proteínas de la Membrana , Persona de Mediana Edad , Técnicas de Cultivo de Órganos , Prostaglandina-Endoperóxido Sintasas/biosíntesis , Prostaglandina-Endoperóxido Sintasas/genética , Membrana Sinovial/metabolismo , Inhibidor Tisular de Metaloproteinasa-1/biosíntesis , Inhibidor Tisular de Metaloproteinasa-1/genética , Receptor fas/biosíntesis , Receptor fas/genética
3.
Bone Marrow Transplant ; 24(9): 1029-31, 1999 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-10556964

RESUMEN

A 24-year-old woman with CML underwent allogeneic BMT in August 1995 from a one-antigen HLA mismatched brother. Conditioning included BuCy2 and CsA and MTX were used to prevent GVHD. In July 1997 she developed right leg pain, lytic bone lesions of distal femur and a solid mass of soft tissue. Histological diagnosis of malignant fibrous histiocytoma was made. Despite treatment with surgery and chemotherapy (doxorubicin and ifosfamide), the patient died 1 year later with local recurrence of the tumor and liver, lung and brain metastases. The CML was in CR.


Asunto(s)
Trasplante de Médula Ósea/efectos adversos , Histiocitoma Fibroso Benigno/etiología , Leucemia Mieloide de Fase Crónica/terapia , Neoplasias Primarias Secundarias/etiología , Adulto , Femenino , Neoplasias Femorales/diagnóstico , Neoplasias Femorales/etiología , Histiocitoma Fibroso Benigno/diagnóstico , Humanos , Masculino , Neoplasias Primarias Secundarias/diagnóstico , Neoplasias de los Tejidos Blandos/diagnóstico , Neoplasias de los Tejidos Blandos/etiología , Trasplante Homólogo
4.
Hybridoma ; 18(4): 377-83, 1999 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-10571269

RESUMEN

The need for increased antibody production by hybridomas has been approached by the addition to cell cultures of different growth factors; in vitro addition of estradiol-17beta (E2) to human blood lymphocytes increases the accumulation of plasma-blasts and Ig-secreting cells. Four different murine-murine hybridomas secreting different monoclonal antibodies (MAbs) were treated with E2. Specific antibody concentration was measured by enzyme-linked immunoadsorbent assay (ELISA) in culture supernatants whereas expression of E2-receptor in the hybridoma cells was determined by polymerase chain reaction (PCR). When E2 was added as a growth supplement to alpha-estrogen receptor positive murine-murine hybridomas it enhanced MAb secretion by as much as 255%, in a dose-dependant manner. This effect lasted for as long as the alpha-estrogen receptor was detected in the hybridoma cells, was inhibited by tamoxifen and was not observed in alpha-estrogen receptor negative hybridomas. The synthetic estrogen analogue diethylstilbestrol had no effect. Estradiol-17beta should be added to the list of hybridoma-inducing growth factors.


Asunto(s)
Formación de Anticuerpos/efectos de los fármacos , Estradiol/inmunología , Estradiol/farmacología , Hibridomas/efectos de los fármacos , Hibridomas/inmunología , Animales , Células Productoras de Anticuerpos/química , Linfocitos B/química , Linfocitos B/efectos de los fármacos , Linfocitos B/inmunología , Dietilestilbestrol/inmunología , Dietilestilbestrol/farmacología , Femenino , Hibridomas/química , Inmunoglobulina G/efectos de los fármacos , Masculino , Ratones , Receptores de Estrógenos/análisis , Receptores de Estrógenos/inmunología
6.
Int J Dev Biol ; 43(1): 59-67, 1999 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-10213083

RESUMEN

Cell surface adhesion and extracellular matrix proteins are known to play a key role in the formation of cell condensations during skeletal development, and their formation is crucial for the expression of cartilage-specific genes. However, little is known about the relationship between adhesion molecules (N-cadherin and N-CAM), extracellular matrix proteins (fibronectin and tenascin) and TGF-beta1, TGF-beta2 and TGF-beta3 during in vitro precartilage condensations in mouse chondrogenesis. On these bases, we determined the participation of mammalian TGF-beta1, TGF-beta2 and TFG-beta3 and Xenopus TGF-beta5 on the expression of cell surface adhesion and extracellular matrix proteins during the formation of precartilage condensations. Also, we characterized the effects of TGF-betas on proteoglycan metabolism at different cellular densities in mouse embryonic limb bud mesenchymal cells. In TGF-beta1 and TGF-beta5-treated cultures, proteoglycan biosynthesis was higher than in controls, while there were no differences in proteoglycan catabolism, which caused the accumulation of cartilage extracellular matrix. When mesenchymal cells were seeded at three different cellular densities in the presence of TGF-betas, only high density cultures presented increased stimulation of proteoglycan biosynthesis, compared to low and intermediate densities. To determine whether the effect of TGF-betas on precartilage condensations is mediated through the expression of N-cadherin, N-CAM, fibronectin and tenascin, we evaluated their expression. Results showed that TGF-beta1, TGF-beta2, TGF-beta3, and TGF-beta5 differentially enhanced the expression of N-cadherin, N-CAM, fibronectin and tenascin in precartilage condensations, suggesting that TGF-beta isoforms play an important role in the establishment of cell-cell and cell-extracellular matrix interactions during precartilage condensations.


Asunto(s)
Cadherinas/metabolismo , Cartílago/embriología , Moléculas de Adhesión Celular/metabolismo , Fibronectinas/metabolismo , Mesodermo/metabolismo , Tenascina/metabolismo , Factor de Crecimiento Transformador beta/farmacología , Animales , Western Blotting , Células Cultivadas , Relación Dosis-Respuesta a Droga , Técnica del Anticuerpo Fluorescente , Glicosaminoglicanos/biosíntesis , Mesodermo/citología , Ratones , Ratones Endogámicos BALB C , Proteoglicanos/biosíntesis , Factores de Tiempo
7.
J Invest Dermatol ; 111(5): 828-34, 1998 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-9804346

RESUMEN

We evaluated the in situ expression of adhesion molecules (E-selectin and vascular cell-adhesion molecule) and proinflammatory/fibrogenic cytokines (IL-1beta, TNF-alpha, TGF-beta1, and PDGF) in sections of normal skin, hypertrophic scar, and hypertrophic scar previously treated with an irradiated mixture of collagen-polyvinylpyrrolidone and completely resolved. Expression of these proteins was detected by indirect immunoperoxidase staining. The hypertrophic scar group displayed an increased amount of IL-1beta, TNF-alpha, TGF-beta1, and PDGF compared with the normal skin and treated scar groups. Values were statistically significant when cytokines in hypertrophic scar and hypertrophic treated sections were compared. Surprisingly, no differences were detected between normal skin and treated scars. On the other hand, differences in levels of E-selectin and vascular cell-adhesion molecule were not statistically significant between the groups, except for vascular cell-adhesion molecule, which decreased in treated scars. Also, supernatants from fibroblast cultures derived from treated hypertrophic scar, showed a reduction in TGF-beta1 and PDGF expression, although apparently collagen synthesis was not affected. Based on previous data from clinical studies in human dermal fibrosis remodeling, and the results presented here, we suggest that collagen-polyvinylpyrrolidone modulates extracellular matrix turnover, mainly of collagen, because expression levels of IL-1beta, TNF-alpha, TGF-beta1, and PDGF were diminished. We infer that collagen-polyvinylpyrrolidone participation could also modify the inflammatory process observed in hypertrophic scarring, by diminishing the expression of adhesion molecules, as a consequence of lower levels of proinflammatory cytokines, mainly IL-1beta and TNF-alpha.


Asunto(s)
Cicatriz Hipertrófica/metabolismo , Colágeno/fisiología , Citocinas/biosíntesis , Povidona/farmacología , Adolescente , Adulto , Moléculas de Adhesión Celular/biosíntesis , Niño , Colágeno/metabolismo , Medios de Cultivo/química , Regulación hacia Abajo , Selectina E/biosíntesis , Femenino , Fibroblastos/citología , Humanos , Interleucina-1/biosíntesis , Masculino , Factor de Crecimiento Derivado de Plaquetas/biosíntesis , Piel/metabolismo , Factor de Crecimiento Transformador beta/biosíntesis , Factor de Necrosis Tumoral alfa/biosíntesis , Molécula 1 de Adhesión Celular Vascular/biosíntesis
8.
Rev Invest Clin ; 50(2): 97-104, 1998.
Artículo en Inglés | MEDLINE | ID: mdl-9658927

RESUMEN

OBJECTIVE: To investigate the spontaneous cytokine gene expression in fibroblasts from patients with diffuse cutaneous systemic sclerosis. Their pattern of expression was correlated with the production of collagen. METHODS: Fibroblasts were obtained from skin biopsies of nine patients diagnosed with systemic sclerosis (mean 16 +/- 8.7 years of disease duration) and ten control individuals. The cytokine gene expression was detected by coupled reverse transcriptase polymerase chain reaction for interleukins 1 beta, 6, 8, tumour necrosis factor-alpha, and transforming growth factor beta. In addition, collagen synthesis was measured by [14C]-proline uptake in fibroblast cultures. RESULTS: All fibroblast samples from patients expressed the interleukin-6 gene (p = 0.04 compared with controls). Eight of the nine patients expressed interleukin-8 (p = 0.02 compared with controls). Four of them expressed also transforming growth factor beta and two more weakly expressed the tumour necrosis factor-alpha gene. Only one patient showed transcription for the interleukin-1 beta gene. In accordance with such immune activation, collagen synthesis was higher in fibroblasts from patients with systemic sclerosis (p = 0.028) as compared with normal controls. Indeed, a positive correlation was found between the expression of IL-6 gene and collagen production (rs = 1). CONCLUSION: The constitutive expression of IL-6 and IL-8 genes by fibroblasts may play an important role in the perpetuation of local immune dysregulation, thus leading to a permanent fibroblast activation in patients with systemic sclerosis.


Asunto(s)
Colágeno/biosíntesis , Citocinas/genética , Expresión Génica , Esclerodermia Sistémica/genética , Adolescente , Adulto , Estudios de Casos y Controles , Células Cultivadas , ADN/análisis , Femenino , Fibroblastos , Humanos , Masculino , Persona de Mediana Edad , Prolina/metabolismo , Esclerodermia Sistémica/inmunología
9.
Clin Genet ; 53(2): 108-13, 1998 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-9611070

RESUMEN

A female with clinical features of familial articular hypermobility syndrome (FAHS) and her family were studied. The subject showed generalized hypermobility, except for a painful shoulder which presented functional limitation with a diagnosis of painful shoulder syndrome. Biochemical studies demonstrated that collagen and glycosaminoglycans (GAGs) contents from skin biopsies of the subject and her family were almost normal. Nevertheless, the densitometric analysis of electrophoretic patterns showed differences in the relative proportions of their collagenous components. They were characterized by changes in type I and III collagens and the presence of type V collagen, in the subject, her father and brother. Also, they presented changes in the types of GAGs, when compared with those of normal skin. Morphological studies revealed a general disorganization of dermal components, a loose collagen network characterized by thick bundles. Also, besides cellular elements, the presence of an abundant darkly staining material was observed. Biochemical and morphological findings permit us to suggest a connective tissue defect, initially described in the FAHS, otherwise known as Ehlers Danlos syndrome (EDS) type XI.


Asunto(s)
Síndrome de Ehlers-Danlos/fisiopatología , Inestabilidad de la Articulación/fisiopatología , Adulto , Colágeno/análisis , Síndrome de Ehlers-Danlos/clasificación , Síndrome de Ehlers-Danlos/patología , Femenino , Glicosaminoglicanos/análisis , Humanos , Inestabilidad de la Articulación/patología , Masculino , Linaje , Piel/química , Piel/patología
13.
Arch Med Res ; 29(4): 291-5, 1998.
Artículo en Inglés | MEDLINE | ID: mdl-9887545

RESUMEN

BACKGROUND: This paper describes the inhibitory effect produced by propranolol pre-treatment on lipid synthesis in flank organs from intact, gonadectomized, and isoproterenol-treated male hamsters. Furthermore, the effect induced by the same treatments on gland sebum composition is reported. METHODS: Different groups of male hamsters were injected daily with propranolol, isoproterenol or propranolol plus isoproterenol. Treatment-effect was evaluated determining the in vitro incorporation of radioactive acetate into lipids in hamster flank organs from intact and castrated animals. Additionally, radiolabeled lipids were isolated and identified using TLC and autoradiography as methods. RESULTS: Results demonstrate that castration significantly decreases lipid synthesis in male hamster flank organs. In addition, propranolol treatment inhibits such synthesis in glands from intact, gonadectomized, and isoproterenol-treated animals. However, isoproterenol treatment was ineffective when compared to intact or gonadectomized control vehicle-treated animals. Lipid classes isolated and identified lipids either in castrated or in drug-treated animals were phospholipids, cholesterol, monoglycerides, fatty acids, waxes and cholesterol esters. CONCLUSIONS: Results indicate an inhibitory effect induced on lipid synthesis by beta-adrenergic receptor antagonists; however, beta-adrenergic agonists drugs do not stimulate it. Data suggest a permissive role of adrenergic hormones on lipid synthesis in intact and in gonadectomized animals. Furthermore, castration decreased the synthesis, suggesting that a tight coupling between beta-adrenergic receptors and androgen receptors may be a prerequisite for lipogenesis in this tissue. Pre-treatment does not modify sebum composition in gonadectomized animal glands. These data support the evidence that activation of beta-adrenergic receptors could be an independent factor in the lipid composition regulation process.


Asunto(s)
Lípidos/antagonistas & inhibidores , Propranolol/farmacología , Glándulas Sebáceas/efectos de los fármacos , Animales , Cromatografía en Capa Delgada , Cricetinae , Metabolismo de los Lípidos , Lípidos/biosíntesis , Masculino , Mesocricetus , Orquiectomía , Glándulas Sebáceas/metabolismo
14.
Cell Calcium ; 22(1): 31-8, 1997 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-9232350

RESUMEN

Maitotoxin (MTX), a water-soluble polyether obtained from the marine dinoflagellate Gambierdiscus toxicus increased intracellular calcium in a concentration-dependent manner in fibroblasts obtained from human skin. The effect of this toxin was both saturable and of high affinity, showing an apparent half activation constant of 450 fM. The toxin did not release intracellular calcium storage compartments nor did the release of these compartments with thapsigargin or ionomycin affect the toxin response. The toxin effect was reduced significantly by pre-incubating the cells with 0.1% trypsin for 30 min, strongly suggesting that the toxin receptor is a plasmalemmal protein. The effect of MTX was partially inhibited by diphenoxylate.


Asunto(s)
Calcio/metabolismo , Toxinas Marinas/farmacología , Oxocinas , Piel/metabolismo , Compartimento Celular , Membrana Celular/química , Membrana Celular/efectos de los fármacos , Membrana Celular/metabolismo , Difenoxilato/farmacología , Relación Dosis-Respuesta a Droga , Fibroblastos/efectos de los fármacos , Fibroblastos/metabolismo , Humanos , Proteínas de la Membrana/efectos de los fármacos , Proteínas de la Membrana/metabolismo , Piel/citología , Piel/efectos de los fármacos , Tripsina/farmacología
15.
Anim Reprod Sci ; 47(3): 211-28, 1997 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-9329863

RESUMEN

Metalloproteinases are an important group of hydrolytic enzymes which participate in interstitial matrix degradation during tissue remodelling processes and therefore may be required during follicular growth and maturation. The activity of metalloproteinases (collagenases, gelatinase, and Pz-peptidase), was measured during growth, maturation and atresia of goat antral follicles. These follicles (n = 67) were separated by size and also classified into four groups: non-atretic (Group I); early atretic (Stage I) (Group II); moderately atretic (Stage II) (Group IIIa); and, late atretic (Stage III) (Group IIIb). Pz-peptidase was greater in granulosa than in thecal cells, and almost absent in follicular fluid. In non-atretic follicles, activity in granulosa cells increased with increasing follicle size, whereas activity peaked in 3-6 mm follicles in thecal cells. Atresia was associated with declining activity in thecal cells from follicles in the 3-6 mm range and in granulosa cells from the > 6 mm range. Interstitial collagenase activity was significant and similar in granulosa and thecal cell extracts and low in follicular fluid from non-atretic follicles. Activity increased significantly in thecal cells, but decreased significantly in granulosa cells from large (> 6 mm) non-atretic follicles. Atresia was associated with declining activity in both types cells and increasing activity in follicular fluid. Gelatinase activity was some times associated with five regions corresponding to molecular weights of 22.1, 30.7, 39.6, 63.8 and 71.4 kDa, and rarely at 91.3 and 81.2 kDa. Overall activity declined with atresia in thecal cells from follicles in the 3-6 mm range, but not in those > 6 mm. In granulosa cells from follicles 3-6 mm, activity varied widely with stage of atresia, while in cells from follicles > 6 mm, activity was greatly increased in atretic follicles.


Asunto(s)
Atresia Folicular/fisiología , Cabras/fisiología , Metaloendopeptidasas/análisis , Folículo Ovárico/enzimología , Animales , Colagenasas/análisis , Colagenasas/metabolismo , Densitometría , Femenino , Líquido Folicular/enzimología , Líquido Folicular/metabolismo , Gelatinasas/análisis , Gelatinasas/metabolismo , Células de la Granulosa/enzimología , Células de la Granulosa/metabolismo , Metaloendopeptidasas/metabolismo , Folículo Ovárico/citología , Folículo Ovárico/fisiología , Embarazo , Células Tecales/enzimología , Células Tecales/metabolismo
16.
Int J Dev Biol ; 41(1): 91-102, 1997 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-9074941

RESUMEN

The present study was performed to determine whether mammalian TGF-beta isoforms and Xenopus TGF-beta 5 elicit a differential chondrogenic response on mesenchymal cells during mouse limb development. Results showed that TGF-beta isoforms produced a distinct chondrogenic pattern depending on embryonic stage. When they were applied to 5 day micromass cultures of limb mesenchymal cells from embryonic stages 19, 20 and 21, a differential response to all four TGF-beta isoforms assayed was observed. By stage 19 the cells formed a uniform sheet of cartilage cells; by stage 20, mesenchymal cells were more responsive to TGF-beta 1 and TGF-beta 5 than at stages 19 and 21, showing an entire cell layer of chondrogenic cells with higher accumulation of extracellular matrix. The diminished effect of TGF-beta 2 and TGF-beta 3 at stages 20 and 21 was accompanied by a nodular pattern of chondrogenic cells rather than by a uniform sheet, as seen at stage 19. At stage 20 TGF-beta 1 and TGF-beta 5 enhanced the expression of sulfated proteoglycans, type II collagen, cartilage link protein and alkaline phosphatase activity. In contrast, TGF-beta 2 and TGF-beta 3 caused less expression in the same parameters. Only a transient exposure to TGF-beta isoforms at days 1 and 2 of culture stimulate chondrogenesis, indicating that TGF-beta isoforms could regulate chondrogenesis at early stages of chondrocyte differentiation. However, when TGF-beta isoforms were applied to low density cultures of mesenchymal cells, chondrogenesis was enhanced only by 25%, suggesting that TGF-beta isoforms enhanced cartilage differentiation to higher levels in micromass cultures than in situations in which little or no chondrogenic differentiation normally occurs.


Asunto(s)
Cartílago/embriología , Proteínas de la Matriz Extracelular , Extremidades/embriología , Factor de Crecimiento Transformador beta/fisiología , Fosfatasa Alcalina/metabolismo , Animales , Colágeno/metabolismo , Matriz Extracelular/metabolismo , Femenino , Edad Gestacional , Masculino , Mesodermo/citología , Ratones , Ratones Endogámicos BALB C , Proteínas/metabolismo , Proteoglicanos/metabolismo , Sulfatos/metabolismo , Xenopus laevis
17.
Biochem Pharmacol ; 52(2): 289-99, 1996 Jul 26.
Artículo en Inglés | MEDLINE | ID: mdl-8694854

RESUMEN

Previous results of our group revealed that mebendazole, a broad spectrum anthelmintic drug with antimicrotubular properties, used for the treatment of liver cirrhosis, decreased total collagen content and biosynthesis in liver upon treatment. In the present study, we have evaluated the effects of mebendazole (5-50 micrograms/mL) on protein synthesis, secretion, and deposition in human-derived fibroblast cultures. The results showed a decrease in cell viability (18.5 +/- 0.9%) at 50 micrograms/mL. [3H]Thymidine incorporation diminished gradually with increasing mebendazole concentrations, reaching a plateau (53.67%) between 30 and 50 micrograms/mL. In late logarithmic phase cultures, the drug caused a decrease of [3H]proline incorporation (43.10%) and collagen biosynthesis (58.61%) in the extracellular matrix. This correlated with an increase in radioactivity in total proteins (51.28%) of the intracellular fraction. Similar results were obtained when mebendazole was assayed in post-confluent fibroblast cultures. The electrophoretic patterns of the extracellular matrix showed a decrease of radioactive collagenous components (alpha chains and beta dimers). By contrast, in the intracellular fraction an increase of radioactive collagen precursors (pro alpha chains) was observed. Immunofluorescence studies and immunotransfer analysis, using polyclonal anti-type I collagen antibodies, revealed an accumulation of intracellular collagen which included: collagen pro alpha chains, alpha chains, and low molecular weight peptides. The results obtained suggest that mebendazole interferes with the transcellular mobilization of proteins, resulting in a decrease of secretion and deposition of extracellular matrix proteins, and an accumulation of intracellular collagenous components. The intracellular accumulation of newly synthesized proteins could cause a feedback regulation in fibroblast cultures.


Asunto(s)
Antinematodos/farmacología , Proteínas de la Matriz Extracelular/biosíntesis , Mebendazol/farmacología , Proteínas de Microtúbulos/biosíntesis , Supervivencia Celular/efectos de los fármacos , Células Cultivadas/efectos de los fármacos , Células Cultivadas/metabolismo , Colágeno/biosíntesis , Electroforesis en Gel de Poliacrilamida , Proteínas de la Matriz Extracelular/metabolismo , Fibronectinas/análisis , Técnica del Anticuerpo Fluorescente , Humanos , Proteínas de Microtúbulos/metabolismo , Prolina/metabolismo , Tritio
20.
Steroids ; 60(9): 630-5, 1995 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-8545853

RESUMEN

The 5 alpha-reduction of levonorgestrel (LNG) as well as its binding capacity to the androgen receptors of the hamster flank organ were investigated. Furthermore, the effects of LNG and its 5 alpha-reduced metabolite in the flank organ test and on [U-14C]glucose incorporation into lipids by this tissue were determined. Homogenates from female hamster flank organs were incubated in the presence of [3H]LNG at pH 7.4. The radioactive 5 alpha-LNG metabolite was isolated and its purity was assessed. Competition experiments for androgen binding receptors were carried out with 1.38 nM [3H-7 alpha-17 alpha]dimethyl-19- nortestosterone (DMNT), Kd, plus a range of increasing concentrations of the different unlabeled steroid hormones. The flank organ test was performed in vivo, and [U-14C]glucose incorporation into lipids was determined under organ culture conditions. The 5 alpha-LNG had the same binding capacity to androgen receptors (AR) as LNG in male flank organs. The flank organ test demonstrated that 5 alpha-LNG activity was similar to that observed for levonorgestrel and testosterone (T) on gonadectomized male hamster flank organs. Topical applications of LNG or 5 alpha-LNG increased [U-14C]glucose incorporation into lipids in a way similar to that of T. The overall data indicate that LNG and 5 alpha-LNG produced androgenic activity in the lipid pathway of male flank organs, and that 5 alpha-reduction is not essential for the LNG effect on this tissue.


Asunto(s)
Levonorgestrel/metabolismo , Receptores Androgénicos/metabolismo , Glándulas Sebáceas/metabolismo , Animales , Unión Competitiva , Castración , Cricetinae , Femenino , Glucosa/metabolismo , Técnicas In Vitro , Levonorgestrel/química , Metabolismo de los Lípidos , Masculino , Oxidación-Reducción , Glándulas Sebáceas/efectos de los fármacos , Testosterona/farmacología
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...