Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 132
Filtrar
Mais filtros

Base de dados
País/Região como assunto
Tipo de documento
País de afiliação
Intervalo de ano de publicação
1.
J Exp Med ; 184(5): 1987-97, 1996 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-8920885

RESUMO

Leukocyte migration from circulation into tissue depends on leukocyte integrin-mediated adhesion to endothelium, but integrins cannot function until activated. However, it remains to be understood how tumor cells adhere to endothelium and infiltrate into underlying tissue. We studied mechanisms of extravasation of leukemic cells using adult T cell leukemia (ATL) cells and report the following novel features of cell surface heparan sulfate proteoglycan on ATL cells in ATL cell adhesion to endothelium: ATL cells adhere to endothelial cells through already activated integrins without exogenous stimulation; different from any other hematopoietic cells, ATL cells express a characteristic heparan sulfate capable of immobilizing heparin-binding chemokine macrophage inflammatory protein (MIP)-1 beta, a potent T cell integrin trigger, produced by the cells themselves; competitive interruption of endogenous heparan sulfate proteoglycan synthesis reduces cell surface MIP-1 beta and prevents ATL cells from integrin-mediated adhesion to endothelial cells or intercellular adhesion molecule-1 triggered through G-protein. We propose that leukemic cells adhere to endothelial cells through the adhesion cascade, similar to normal leukocyte, and that the cell surface heparan sulfate, particularly on ATL cells, is pivotally involved in chemokine-dependent autocrine stimulation of integrin triggering by immobilizing the chemokine on them.


Assuntos
Adesão Celular , Endotélio Vascular/metabolismo , Heparitina Sulfato/metabolismo , Integrinas/metabolismo , Leucemia de Células T/metabolismo , Proteoglicanas/metabolismo , Linfócitos T CD4-Positivos/metabolismo , Adesão Celular/efeitos dos fármacos , Linhagem Celular , Membrana Celular/química , Quimiocina CCL4 , Endotélio Vascular/citologia , Citometria de Fluxo , Glicosídeos/farmacologia , Proteoglicanas de Heparan Sulfato , Heparitina Sulfato/análise , Humanos , Molécula 1 de Adesão Intercelular/farmacologia , Leucemia Prolinfocítica de Células T/metabolismo , Infiltração Leucêmica , Proteínas Inflamatórias de Macrófagos/biossíntese , Proteínas Inflamatórias de Macrófagos/genética , Modelos Biológicos , Metástase Neoplásica , Fenótipo , Proteoglicanas/análise , RNA Mensageiro/análise , RNA Neoplásico/análise , Células Tumorais Cultivadas
2.
J Clin Invest ; 66(3): 612-5, 1980 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-6156957

RESUMO

In vivo androgen kinetics were determined in six young (21--49 yr) and elderly men (62-77 yr) with prostatge hyperplasia (BPH). Steady-state infusions of [14C]testosterone and [3H]androstanediol (3 alpha diol) were given, which allowed determination of the conversions testosterone leads to dihydrotesterone (DHT) in equilibrium or formed from 3 alpha diol. These infusions also yield metabolic clearance data which, together with meaurement of nonisotopic steroid levels, yield estimations of blood production rates. The production rate for testosterone was 6.04 +/- 1.66 vs. 3.69 +/- 0.62 mg/d, whereas the production rate for 3 alpha diol was 319 +/- 57 and 193 +/- 34 micrograms/d (P < 0.05 both groups). The irreversible conversion rate of testosterone to DHT was 3.1 +/- 0.4 and 3.5 +/- 0.9% (NS). The back conversion of 3 alpha diol to dHT was high (68 +/- 25 vs. 81 +/- 17, NS) indicating that 3 alpha diol might cause BPH as a result of conversion to DHT in vivo. The conversion of DHT to 3 alpha diol is reduced in the elderly group (15.8 +/- 2.6 and 6.3 +/- 1.4, P < 0.001). Since DHT formation in the prostate is a key event in the development of BPH and blood DHT appears to be a measure of extrasplanchnic sexual target tissue activity, our in vivo studies suggest that the tissue increase in DHT may result from reduced metabolism and the activity of 3 alpha-oxidoreduction favors the oxidative pathway in elderly men.


Assuntos
Envelhecimento , Di-Hidrotestosterona/metabolismo , Hiperplasia Prostática/metabolismo , Adulto , Idoso , Androstano-3,17-diol/sangue , Biotransformação , Di-Hidrotestosterona/sangue , Humanos , Cinética , Masculino , Taxa de Depuração Metabólica , Pessoa de Meia-Idade , Testosterona/sangue
3.
Cancer Res ; 58(18): 4138-45, 1998 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-9751626

RESUMO

Tumor-reactive T cells, known as tumor-infiltrating lymphocyte(TIL)s are known to infiltrate various tumors. Although TILs exert cytotoxic activities against tumor cells, only a small percentage of tumors usually contain TILs that specifically react to tumor antigens. Because the exact role of these lymphocytes is unclear, we investigated the mechanisms of migration and adhesion of TILs to bone metastatic tumors, particularly to osteoblasts and bone marrow-derived stromal cell(BMSC)s. Histopathological examination showed that most TILs in secondary bone metastatic tumors (from primary tumors in the lung or breast) were found in the supporting tissue stroma between the bone and tumor mass. Cultured TILs (obtained from breast tumors) adhered spontaneously to osteoblasts and BMSCs (obtained from patients with osteoarthritis) without exogenous stimulation. Adhesion was further enhanced by chemokines macrophage inflammatory protein (MIP)-1alpha and MIP-1beta. TILs highly expressed activation antigens CD25 and CD69. A spontaneous activation of an integrin, lymphocyte function-associated antigen-1 (LFA-1), was also detected on TILs. TILs produced high concentrations of MIP-1alpha and MIP-1beta and spontaneous polymerization of cytoskeletal F-actin was observed in these cells. Adhesion of TILs to osteoblasts and BMSCs via LFA-1 and very late antigen-4 was associated with the production of osteoclastogen interleukin 6 by the latter cells. Our results indicate that integrins on TILs are activated in an autocrine manner by MIP-1alpha and MIP-1beta, and that treatment with the chemokines increases the binding of TILs on osteoblasts and stromal cells via a mechanism involving intercellular adhesion molecule-1 and vascular cell adhesion molecule-1 as targets for the integrin. Our data also indicated that interactions between TILs and osteoblasts/stromal cells lead to the secretion by the latter of the osteoclastogenic cytokine interleukin 6.


Assuntos
Medula Óssea/imunologia , Neoplasias Ósseas/imunologia , Imunoterapia Adotiva/métodos , Integrinas/metabolismo , Linfócitos do Interstício Tumoral/fisiologia , Actinas/metabolismo , Antígenos CD/metabolismo , Antígenos de Diferenciação de Linfócitos T/metabolismo , Medula Óssea/metabolismo , Neoplasias Ósseas/secundário , Neoplasias Ósseas/terapia , Adesão Celular/fisiologia , Movimento Celular/fisiologia , Quimiocina CCL3 , Quimiocina CCL4 , Feminino , Humanos , Molécula 1 de Adesão Intercelular/metabolismo , Interleucina-6/metabolismo , Lectinas Tipo C , Antígeno-1 Associado à Função Linfocitária/metabolismo , Linfócitos do Interstício Tumoral/metabolismo , Proteínas Inflamatórias de Macrófagos/metabolismo , Osteoblastos/imunologia , Osteoblastos/metabolismo , Polímeros , Receptores de Interleucina-2/metabolismo , Células Estromais/metabolismo , Regulação para Cima , Molécula 1 de Adesão de Célula Vascular/metabolismo
4.
J Bone Miner Res ; 12(10): 1657-63, 1997 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9333126

RESUMO

The articular cartilage consists of resident chondrocytes embedded within the extracellular matrix which contains several components such as collagen and hyaluronic acids (HA). CD44 is a major cell surface receptor for HA and is homologous to cartilage-link proteins. Although CD44 is present in cartilage, it is not clear if chondrocytes adhere to HA through CD44 or whether such adhesion changes the function of chondrocytes. We studied the molecular mechanisms of CD44-related chondrocyte adhesion to HA and the effects of such adhesion on chondrocyte function. Experiments were performed using the human chondrosarcoma-derived chondrocyte-like cell line HCS-2/8. Our results showed that (a) HCS-2/8 cells highly expressed CD44; (b) HCS-2/8 cells efficiently adhered to HA without any stimuli; (c) monoclonal antibody (mAb)-blocking studies indicated that adhesion of HCS-2/8 cells to HA was mainly mediated by the CD44/HA pathway; (d) cellular adhesion to HA increased the proliferation of HCS-2/8 cells, independent of transforming growth factor-beta (TGF-beta), but this was inhibited by CD44 mAb; (e) the adhesion of chondrocytes to HA also induced c-myc mRNA expression and this was also inhibited by CD44 mAb; and (f) the adhesion of cells to HA augmented TGF-beta mRNA expression, a process also reduced by CD44 mAb. Thus, HCS-2/8 cells effectively adhered to HA through cell surface CD44. The adhesion was also involved in cellular signaling which induced cellular proliferation and expression of c-myc mRNA as well as TGF-beta mRNA expression within the cells. Our results indicate that CD44 on chondrocytes plays an important role in normal and abnormal functions of cartilage through its adhesion to HA, which induces a variety of stimulatory signals to regulate chondrocyte proliferation as well as matrix synthesis in cartilage microenvironment.


Assuntos
Adesão Celular/fisiologia , Condrócitos/fisiologia , Receptores de Hialuronatos/fisiologia , Ácido Hialurônico/fisiologia , Anticorpos Monoclonais , Northern Blotting , Divisão Celular/fisiologia , Condrócitos/imunologia , Citometria de Fluxo , Genes myc/genética , Humanos , Receptores de Hialuronatos/imunologia , RNA Mensageiro/biossíntese , Transdução de Sinais/genética , Fator de Crescimento Transformador beta/biossíntese , Fator de Crescimento Transformador beta/genética , Células Tumorais Cultivadas
5.
J Bone Miner Res ; 10(10): 1462-9, 1995 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-8686501

RESUMO

The two major processes of bone metabolism--bone formation and resorption--are regulated by cellular interactions. Osteoblasts and osteoclasts play a significant role in bone metabolism, which is known to be regulated by local soluble factors and systemic hormones. Although bone is a heterogeneous tissue comprised of osteogenic and hematopoietic cells, cellular adhesion of osteoblasts and its regulation remains to be understood. We first demonstrate that cellular adhesion by which osteoblasts communicate with opposing cells in bone milieu is involved in the osteoblast activation: (a) purified human osteoblasts obtained from osteoarthritis patients expressed particular adhesion molecules, ICAM-1, VCAM-1, and LFA-3; (b) toe osteoblasts adhered to T cells which were used as representative adhesive partners, since T cells possess all the receptors to these adhesion molecules; (c) mRNA transcription and secretion of IL-1beta and IL-6 were induced in the osteoblasts by the cellular adhesion to T cells and they were reduced by interrupting the adhesion; (d) cross-linking of ICAM-1 and VCAM-1 on the osteoblasts induced IL-6 secretion from the osteoblasts. These results indicate that osteoblasts adhere to opposing cells through particular adhesion molecules on their surface and that the adhesion molecules on the osteoblasts not only function as glue with opposing partners but transduce activation signals that facilitate the production of bone-resorbing cytokines. We propose that cellular adhesion of osteoblasts as well as soluble factors is significant for the regulation of bone metabolism.


Assuntos
Molécula 1 de Adesão Intercelular/fisiologia , Osteoblastos/fisiologia , Molécula 1 de Adesão de Célula Vascular/fisiologia , Sequência de Bases , Adesão Celular , Linhagem Celular , Citocinas/biossíntese , Humanos , Ativação Linfocitária , Dados de Sequência Molecular , Osteoblastos/química , Osteoblastos/citologia , Fenótipo , Linfócitos T/imunologia , Linfócitos T/fisiologia , Acetato de Tetradecanoilforbol
6.
J Bone Miner Res ; 9(10): 1533-9, 1994 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-7817798

RESUMO

We examined the in vivo effects of recombinant murine IL-4 (rmIL-4) on spontaneous and stimulated mouse osteoclast formation. EC-GI cells, which produce PThrP and IL-1 alpha, were explanted in nude mice. These EC-GI cell-bearing nude mice developed hypercalcemia (4.90 +/- 0.68 mM), and the calcium levels were decreased to near normal (3.48 +/- 0.73 mM, p < 0.05) at day 3 by continuous infusion of rmIL-4 at a dose of 7 micrograms/day. When infused with 0.6 nmol/day of PTHrP(1-34) in ICR mice, rmIL-4 at a dose of 1 or 5 micrograms/day for 3 days caused a marked inhibitory effect on hypercalcemia induced by PTHrP(1-34) (3.73 +/- 0.56-2.54 +/- 0.14 mM, p < 0.01). However, rmIL-4 alone did not change the serum calcium in mice. Histomorphometric analysis revealed that rmIL-4 inhibits both spontaneous and PTHrP(1-34)-stimulated osteoclast formation in mice, with a decrease in osteoclastic surface and in the number of osteoclasts per mm bone surface, respectively. We conclude that IL-4 inhibits spontaneous and stimulated bone resorption resulting from inhibition of osteoclast formation and modulates the development of humoral hypercalcemia of malignancy.


Assuntos
Interleucina-4/farmacologia , Osteoclastos/efeitos dos fármacos , Proteína Relacionada ao Hormônio Paratireóideo , Fragmentos de Peptídeos/toxicidade , Proteínas/toxicidade , Animais , Reabsorção Óssea/tratamento farmacológico , Cálcio/sangue , Carcinoma de Células Escamosas/patologia , Contagem de Células , Modelos Animais de Doenças , Neoplasias Esofágicas/patologia , Feminino , Fêmur/citologia , Fêmur/efeitos dos fármacos , Humanos , Hipercalcemia/tratamento farmacológico , Hipercalcemia/metabolismo , Hipercalcemia/patologia , Bombas de Infusão Implantáveis , Interleucina-4/administração & dosagem , Interleucina-4/uso terapêutico , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos ICR , Camundongos Nus , Transplante de Neoplasias , Osteoclastos/fisiologia , Hormônio Paratireóideo/farmacologia , Proteínas Recombinantes/administração & dosagem , Proteínas Recombinantes/farmacologia , Proteínas Recombinantes/uso terapêutico , Células Tumorais Cultivadas
7.
Endocrinology ; 138(5): 2066-72, 1997 May.
Artigo em Inglês | MEDLINE | ID: mdl-9112406

RESUMO

PTH and PTH-related peptide (PTHrP) bind to a type I PTH/PTHrP receptor expressed in bone and kidney or a type II receptor in nonclassical target tissue with equal affinity and similar bioactivities. PTHrP is abundant in the central nervous system, but its physiological role remains unknown. Herein, we examined the role of PTHrP-(1-34) on arginine vasopressin (AVP) release from the rat supraoptic nucleus (SON). Application of PTHrP-(1-34) to SON slices caused an increase in AVP release in a concentration-dependent manner. Neither PTHrP-(7-34) nor PTH-(1-34) had any effect on AVP release from the SON. PTHrP-(1-34)-induced AVP release was antagonized by a large excess of PTHrP-(7-34) and by H89, an inhibitor of cAMP-dependent protein kinase (A kinase), but not by PTH-(1-34) or PTH-(13-34). PTHrP-(1-34), but not PTH-(1-34), also dose-dependently increased the levels of cAMP in the SON. 125I-Labeled PTHrP-(1-34) bound specifically to crude membranes isolated from the SON. Scatchard analysis showed a single class of binding sites for PTHrP-(1-34) with a Kd of 36.4 nM and a maximum binding capacity of 3.94 pmol/mg protein. No specific binding for 125I-labeled PTH-(1-34) was noted. The binding of 125I-labeled PTHrP-(1-34) was displaced by unlabeled PTHrP-(1-34) and unlabeled PTHrP-(7-34), but not by unlabeled PTH-(1-34). These findings suggest that PTHrP-(1-34), but not PTH-(1-34), causes the release of AVP from the SON through a novel receptor distinct from type I or II PTH/PTHrP receptors.


Assuntos
Arginina Vasopressina/metabolismo , Proteína Relacionada ao Hormônio Paratireóideo , Fragmentos de Peptídeos/farmacologia , Proteínas/farmacologia , Sulfonamidas , Núcleo Supraóptico/efeitos dos fármacos , Núcleo Supraóptico/metabolismo , Animais , Membrana Celular/metabolismo , AMP Cíclico/metabolismo , Proteína Quinase Tipo II Dependente de AMP Cíclico , Proteínas Quinases Dependentes de AMP Cíclico/antagonistas & inibidores , GMP Cíclico/metabolismo , Inibidores Enzimáticos/farmacologia , Isoquinolinas/farmacologia , Masculino , Fragmentos de Peptídeos/metabolismo , Proteínas/metabolismo , Ratos , Ratos Wistar
8.
Endocrinology ; 139(1): 383-8, 1998 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9421437

RESUMO

It has been suggested that PTH-related protein (PTHrP) is an endogenous modulator of cardiovascular systems. We have reported that PTHrP(1-34), but not PTH(1-34), causes the release of arginine-vasopressin (AVP) from the supraoptic nucleus (SON) of the hypothalamus in vitro through a novel receptor distinct from the PTH/PTHrP receptors (type I or type II) described previously. In this study, we have investigated the in vivo effects of PTHrP(1-34) on AVP secretion and its, messenger RNA (mRNA) expression in the SON in conscious rats. Intracerebroventricular (i.c.v.) administration of PTHrP(1-34) resulted in an increase in plasma AVP concentration in a dose-dependent manner (0-400 pmol/rat). The maximal effect was obtained at 15 min after i.c.v. administration of PTHrP(1-34). Neither PTHrP(7-34) nor PTH(1-34) had any effect on plasma AVP levels. PTHrP(1-34)-induced AVP secretion was antagonized by pretreatment with PTHrP(7-34) but not by that with PTH(1-34). In addition, in situ hybridization study revealed that AVP mRNA expression in the SON and paraventricular nucleus was significantly increased 30 min after i.c.v. administration of PTHrP(1-34) and reached a maximum at 180 min. Furthermore, in Northern blot analyses, AVP mRNA expression in the SON was increased to approximately a 2-fold of basal level by PTHrP(1-34). On the other hand, neither PTHrP(7-34) or PTH(1-34) had any effect on the mRNA expression. The PTHrP(1-34)-stimulated AVP mRNA expression was eliminated by pretreatment with PTHrP(7-34) but not with PTH(1-34). These results suggest that, in the central nervous system, PTHrP(1-34) is involved in AVP secretion through a novel receptor distinct from the PTH/PTHrP receptors reported previously, playing a role in the body water and electrolyte homeostasis.


Assuntos
Arginina Vasopressina/metabolismo , Proteínas/farmacologia , Núcleo Supraóptico/metabolismo , Teriparatida/farmacologia , Animais , Arginina Vasopressina/genética , Northern Blotting , Hibridização In Situ , Injeções Intraventriculares , Masculino , Proteína Relacionada ao Hormônio Paratireóideo , Proteínas/administração & dosagem , RNA Mensageiro/análise , Ratos , Ratos Wistar , Receptor Tipo 1 de Hormônio Paratireóideo , Receptores de Hormônios Paratireóideos/fisiologia , Teriparatida/administração & dosagem
9.
J Clin Endocrinol Metab ; 52(4): 772-8, 1981 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-7204542

RESUMO

The in vivo origin of androstanediol (3 alpha diol) and its glucuronide was studied in six young and five elderly men undergoing cardiac catheterization. Constant infusions of [14C]testosterone and [3H]3 alpha diol were given, and blood was obtained from the aorta and hepatic vein in order to measure metabolic clearance, splanchnic extraction, and the possibility of splanchnic production of both 3 alpha diol and its glucuronide. In young elderly men, the concentrations of labeled and unlabeled testosterone, dihydrotestosterone, and 3 alpha diol were lower in the hepatic vein than in the aorta. The specific activities of dihydrotestosterone and 3 alpha diol were the same in blood entering and leaving the splanchnic compartment. The plasma concentration of 3 alpha diol was 18 +/- 2 in the young men and 15 +/- 4 ng/dl in the elderly group. However, the blood production rate of 3 alpha diol determined from the metabolic clearance and morning plasma concentration was reduced (324 vs. 199 micrograms/day) as a result of lower clearance in the elderly men. Plasma 3 alpha diol glucuronide concentrations were 197 +/- 68 and 96 +/- 35 ng/dl in the two groups. No difference in the concentration of 3 alpha diol glucuronide was observed across the splanchnic tissues by mass, radioactive levels, specific activity, or 14C to 3H ratios. The 14C to 3H ratio for 3 alpha diol glucuronide was 10 times higher than for the free steroid, indicating that more than 90% of the glucuronide originates from a pool separate from blood 3 alpha diol. Both the splanchnic extraction of 3 alpha diol and the metabolic clearance were reduced in elderly men. These studies indicate that both 3 alpha diol and its glucuronide in blood result from extrasplanchnic events. A major reduction in the plasma concentration of 3 alpha diol glucuronide occurs in the aging male, although no difference is seen in the levels of the unconjugated 3 alpha diol. 3 alpha diol and its glucuronide are derived principally by extrahepatic (target) tissue events.


Assuntos
Androstano-3,17-diol/sangue , Androstanóis/sangue , Adulto , Fatores Etários , Idoso , Androgênios/sangue , Androstano-3,17-diol/análogos & derivados , Aorta , Di-Hidrotestosterona/sangue , Veias Hepáticas , Humanos , Masculino , Taxa de Depuração Metabólica , Pessoa de Meia-Idade , Testosterona/sangue
10.
J Clin Endocrinol Metab ; 76(1): 127-33, 1993 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-8421076

RESUMO

We reported first in this study that human thyroid cell line NIM 1 established from a patient with papillary adenocarcinoma of the thyroid associated with hypercalcemia and peripheral neutrocytosis produced interleukin (IL)-1 alpha and IL-1 beta in the culture supernatant and cell lysate as detected by murine thymocyte proliferative response and enzyme-linked immunosorbent assay. Production of IL-1 alpha and IL-1 beta was further confirmed by the demonstration of IL-1 alpha and IL-1 beta messenger ribonucleic acid expression with Northern blot hybridization analysis. The in vitro growth of NIM 1 cells was inhibited by the addition of anti-IL-1 alpha and IL-1 beta antibody. The growth of NIM 1 cells was further enhanced by the addition of recombinant human IL-1 alpha and IL-1 beta, whereas this enhancement was also inhibited by the addition of anti-IL-1 antibody. IL-1 receptors were expressed on NIM 1 cells. These results suggest that IL-1 plays a regulatory role in the growth of NIM 1 cells by an autocrine mechanism.


Assuntos
Adenocarcinoma/patologia , Divisão Celular/efeitos dos fármacos , Interleucina-1/farmacologia , Neoplasias da Glândula Tireoide/patologia , Adenocarcinoma/genética , Adenocarcinoma/imunologia , Animais , Anticorpos/farmacologia , Fator Estimulador de Colônias de Granulócitos e Macrófagos/farmacologia , Humanos , Interleucina-1/genética , Interleucina-1/imunologia , Camundongos , Camundongos Nus , Transplante de Neoplasias , RNA Mensageiro/análise , Receptores de Interleucina-1/análise , Receptores de Interleucina-1/metabolismo , Proteínas Recombinantes/farmacologia , Linfócitos T/imunologia , Neoplasias da Glândula Tireoide/genética , Neoplasias da Glândula Tireoide/imunologia , Transplante Heterólogo , Células Tumorais Cultivadas
11.
J Clin Endocrinol Metab ; 75(2): 632-5, 1992 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-1379259

RESUMO

The conversion of testosterone to dihydrotestosterone (DHT) by 5 alpha-reductase and the interconversion between DHT and 5 alpha-Androstane-3 alpha,17 beta-diol (3 alpha-diol) by 3 alpha-hydroxysteroid oxidoreductase (3 alpha-HSOR) were studied in fibroblasts derived from the genital skin of 15 prepubertal boys (2-10 yr), 17 young men (20-40 yr), 13 elderly men (60-78 yr) without clinically evident prostatic pathology, and 17 elderly men (61-88 yr) with benign prostatic hyperplasia (BPH). Respective DHT formations from testosterone (5 alpha-reduction) and 3 alpha-diol (3 alpha-HSOR oxidation) were not different among genital skin fibroblasts of the 4 groups. However, DHT degradation to 3 alpha-diol (3 alpha-HSOR reduction) was significantly lower in fibroblasts from elderly men with BPH than in those from the prepubertal boys (P less than 0.01), the young men (P less than 0.01), and the elderly men without BPH (P less than 0.05). 3 beta-HSOR reduction in fibroblasts of the BPH group was significantly lower (P less than 0.05) than in those of the elderly men without BPH; however, it did not differ from values for the prepubertal boys and the young men. (3 alpha + 3 beta)-HSOR reduction was also significantly lower (P less than 0.05) in the BPH group than respective values of the three other groups. These results indicate that DHT accumulation may occur in genital skin fibroblasts from elderly men with BPH, resulting from a shift in the overall balance of androgen metabolism, which favors the net formation of DHT.


Assuntos
Envelhecimento/metabolismo , Di-Hidrotestosterona/metabolismo , Genitália Masculina/metabolismo , Hiperplasia Prostática/metabolismo , Pele/metabolismo , Idoso , Androstano-3,17-diol/metabolismo , Células Cultivadas , Fibroblastos/metabolismo , Genitália Masculina/patologia , Humanos , Masculino , Hiperplasia Prostática/patologia , Pele/patologia
12.
J Clin Endocrinol Metab ; 56(5): 915-9, 1983 May.
Artigo em Inglês | MEDLINE | ID: mdl-6300176

RESUMO

This is the first autopsy case of male 17 alpha-hydroxylase deficiency with malignant hypertension. The subject had hypertension, hypokalemic alkalosis, and pseudohermaphroditism. At age 21, 17 alpha-hydroxylase deficiency was diagnosed by low urinary excretion of 17-hydroxysteroids, low secretion rate of cortisol, and low plasma testosterone level in association with high urinary excretion of pregnanediol and high plasma progesterone and corticosterone. Urinary excretion of aldosterone and PRA were suppressed, and plasma ACTH was elevated. Hypertension and hypokalemic alkalosis were normalized with dexamethasone therapy. After missing 5 yr of follow-up, malignant hypertension developed, and PRA and aldosterone were elevated. Histological examination revealed some characteristic arteriolar lesions as in malignant nephrosclerosis. Juxtaglomerular hyperplasia and an increase of renin granules were observed, which reflected high PRA. Abnormal histological findings of endocrine organs were observed in the breast, the pituitary gland, the adrenal glands, and the testis.


Assuntos
Hiperplasia Suprarrenal Congênita , Hipertensão Maligna/etiologia , Esteroide Hidroxilases/deficiência , Hormônio Adrenocorticotrópico/sangue , Adulto , Aldosterona/metabolismo , Alcalose/etiologia , Dexametasona/uso terapêutico , Transtornos do Desenvolvimento Sexual/etiologia , Humanos , Hipertensão Maligna/patologia , Hipertensão Maligna/fisiopatologia , Hipopotassemia/etiologia , Masculino , Renina/sangue
13.
J Clin Endocrinol Metab ; 62(2): 410-2, 1986 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-3753608

RESUMO

Thyroglobulin (Tg) can be detected in the circulation of normal subjects. Serum Tg is increased in patients with various thyroidal disorders including Graves' disease; however, little is known about Tg metabolism. Therefore, a kinetic study of human Tg was carried out in 13 normal men, 19-28 yr old, and 6 untreated hyperthyroid patients with Graves' disease, 3 men (22 to 25 yr old), and 3 women (21 to 63 yr old). Ten milligrams of Tg were injected as a bolus dose. Blood samples were collected before and 10 min, and 2, 4, 6, 8, 12 h and every 12 h up to 72 h after injection. Concentrations of serum Tg were measured by an RIA method developed in our laboratory. Anti-Tg antibody was not detected in any subject. Various indices of this kinetic study were calculated using single compartmental analysis. In 13 normal subjects, the mean serum concentrations of Tg were 17 +/- 12.6 (SD) ng/ml; mean half-life was 29.6 +/- 2.8 h; distribution volume was 11,210 +/- 3,076 ml/60 kg body weight; fractional decay was 2.40 +/- 0.22%/h; MCR was 268.9 +/- 87.8 ml/h X 60 kg; and release rate was 100.3 +/- 50.2 micrograms/day X 60 kg. Serum concentrations of Tg were increased in four of the six untreated hyperthyroid patients with Graves' disease. Their Tg half-lives and MCR were within the normal range. In the two patients who had normal serum concentrations of Tg, the Tg half-lives were shorter and MCR were greater than in normal subjects. The release rates of Tg were increased in all six of these patients. In summary, in hyperthyroid patients, Tg release is significantly greater than normal, whereas Tg metabolism is similar to that in normal subjects.


Assuntos
Doença de Graves/sangue , Tireoglobulina/sangue , Adulto , Idoso , Feminino , Meia-Vida , Humanos , Cinética , Masculino , Taxa de Depuração Metabólica , Pessoa de Meia-Idade , Radioimunoensaio
14.
J Clin Endocrinol Metab ; 64(5): 949-53, 1987 May.
Artigo em Inglês | MEDLINE | ID: mdl-3031123

RESUMO

Thyroid epithelial cells (thyrocytes) in autoimmune thyroid disease have been found to express DR antigens on their surfaces, and interferon-gamma (IFN gamma) induces DR antigen expression. This study was undertaken to determine the effect of IFN gamma on the response of human thyrocytes to TSH stimulation and the relationship between the response to TSH and the expression of DR antigen induced by IFN gamma, using monolayer cultures of Graves' thyrocytes. When confluent thyrocyte monolayers were incubated with TSH or Bu2cAMP (DBcAMP) for 7-9 days, T3 and thyroglobulin concentrations in the culture medium increased gradually in a dose-dependent manner. However, when TSH or DBcAMP was added after the cells had been cultured for 4 days with IFN gamma, T3 and thyroglobulin secretion in response to both 10 mU/mL TSH and 1 mM DBcAMP was significantly inhibited. The inhibition by IFN gamma was dose dependent and correlated with the number of DR antigen-positive thyrocytes present on the last day of culture. IFN alpha and -beta did not affect the response of thyrocytes to TSH or DBcAMP stimulation. These results suggest that DR antigen-positive thyrocytes fail to respond to TSH stimulation at a site located distal to cAMP formation.


Assuntos
Antígenos HLA-D/biossíntese , Antígenos HLA-DR/biossíntese , Interferon gama/farmacologia , Glândula Tireoide/metabolismo , Tireotropina/farmacologia , Bucladesina/farmacologia , Células Cultivadas , Epitélio/imunologia , Epitélio/metabolismo , Humanos , Tireoglobulina/metabolismo , Glândula Tireoide/efeitos dos fármacos , Glândula Tireoide/imunologia , Tri-Iodotironina/metabolismo
15.
J Clin Endocrinol Metab ; 85(1): 382-9, 2000 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10634414

RESUMO

Graves' disease (GD) is an autoimmune thyroid disease characterized by infiltration of lymphocytes into the thyroid, and intrathyroid lymphocytes are known to play an important role in the pathogenesis of GD. However, it remains to be understood how lymphocytes adhere to thyrocytes and regulate the thyrocyte function through cellular adhesion. We studied the mechanisms of T cell adhesion to thyrocytes using intrathyroid mononuclear cells (ITMC) and thyrocytes purified from the thyroids of patients with GD. The following novel features of cellular adhesion of ITMC to thyrocytes in the regulation of the thyrocyte function in GD were observed: 1) GD-ITMC expressed lymphocyte function-associated antigen (LFA)-1, which became an active adhesive configuration much higher than peripheral blood mononuclear cells (PBMC) from normal volunteers and GD patients; 2) GD-thyrocytes expressed a high quantity of intercellular adhesion molecule (ICAM)-1; 3) GD-ITMC adhered to GD-thyrocytes, whereas normal PBMC required activation stimuli by phorbol myriacetate, a pharmacological integrin-trigger, to adhere to GD- thyrocytes; 4) monoclonal antibody-blocking studies showed that the adhesion of the activated PBMC and ITMC to thyrocytes was mainly mediated by the LFA-1/ICAM-1 pathway; 5) the adhesion of GD-thyrocytes to the activated-PBMC or ITMC induced the proliferation of the thyrocytes, which was blocked by the addition of ICAM-1 and/or LFA-1 monoclonal antibodies; and 6) in GD thyrocytes of early cultures, ICAM-1 expression on GD-thyrocytes and its adhesion to LFA-1 on phorbol myriacetate-activated PBMC or ITMC were not modulated by the addition of interleukin-1beta or interferon-gamma, and proliferation of thyrocytes by the cellular adhesion via the ICAM-1/LFA-1 pathway was independent of the proliferative response of these cytokines. Taken together, these results suggest that lymphocytes infiltrating GD thyroid induce proliferation of GD-thyrocyte by the cellular adhesion to thyrocytes via ICAM-1/LFA-1, which may lead to the development of a goiter.


Assuntos
Doença de Graves/patologia , Molécula 1 de Adesão Intercelular/fisiologia , Antígeno-1 Associado à Função Linfocitária/fisiologia , Linfócitos/fisiologia , Glândula Tireoide/patologia , Adesão Celular/fisiologia , Divisão Celular/fisiologia , Células Cultivadas , Citofotometria , Doença de Graves/metabolismo , Humanos , Interferon gama/farmacologia , Interleucina-1/farmacologia , Monócitos/fisiologia , Transdução de Sinais/fisiologia , Glândula Tireoide/metabolismo
16.
J Clin Endocrinol Metab ; 49(3): 381-6, 1979 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-224075

RESUMO

A 35-yr-old woman with Nelson's syndrome presented with amenorrhea and virilization. Serum testosterone (T) concentration was 605 ng/dl and fell to 33 ng/dl when dexamethasone was administered. The MCR of T fell from 1383 to 991 liters/day and the T production rate decreased by 96%. With administration of synthetic ACTH, T concentration rose to 338 ng/dl. Plasma ACTH concentration paralleled T during repeated suppression testing, suggesting that T secretion was dependent on ACTH hypersecretion. Preoperative and intraoperative ovarian vein catheterization suggested that the predominant source of androgen production was from the right ovarian vein. Laporatomy revealed multiple paraovarian tumors in the right mesosalpinyx and mesovarium. Incubation of tumor slices and ovarian tissue with [3H]pregnenolone and [14C]17-hydroxyprogesterone demonstrated conversion of both precursors to T by the tumor and confirmed that the tumors were the source of androgen excess. The microscopic appearance of the tumors closely resembled the morphology of testicular and paratesticular tumors of men with congenital adrenal hyperplasia and Nelson's syndrome. The analogous dependency of the tumors on ACTH hypersecretion in men with paratesticular tumors and in this woman with paraovarian tumors suggests that the tumors may arise in both males and females from a common steroid-secreting cell of adrenogenital origin.


Assuntos
Hormônio Adrenocorticotrópico/metabolismo , Síndrome de Nelson/complicações , Neoplasias Ovarianas/etiologia , Neoplasias Hipofisárias/complicações , Testosterona/biossíntese , Hormônio Adrenocorticotrópico/sangue , Adulto , Dexametasona/farmacologia , Feminino , Humanos , Síndrome de Nelson/fisiopatologia , Neoplasias Ovarianas/metabolismo , Pregnenolona/metabolismo , Testosterona/sangue
17.
Bone ; 22(4): 361-5, 1998 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9556136

RESUMO

Estrogen deficiency contributes to an increase in bone resorption and bone formation characterized by a high rate of bone turnover. Interleukin-4 (IL-4) is a rapid and potent inhibitor of bone resorption. We examined the short term in vivo effects of recombinant murine IL-4 (rmIL-4) on bone remodeling in normal and ovariectomized mice. Eight-week-old mice were randomized into the following five groups: (1) sham-operated mice (sham); (2) sham-operated mice infused with rmIL-4; (3) ovariectomized mice (ovx); (4) ovx infused with rmIL-4; and (5) ovx replaced by 10 or 20 microg of 17beta-estradiol (E2) for 14 or 28 days after ovariectomy, respectively. rmIL-4 at a dose of 5 microg/day was infused into ovx and sham for 3 days prior to sacrifice. Analyses were performed 14 and 28 days after operation. An increase in serum alkaline phosphatase and urinary deoxypyridinoline levels induced by ovariectomy was inhibited by the 3-day infusion of rmIL-4. In ovx, serum and urinary IL-6 levels were also increased significantly 14 days after ovariectomy, which were restored by E2 but not by rmIL-4. Histomorphometrical analysis of trabecular bone revealed that the 3-day infusion of rmIL-4 inhibited the high rate of bone turnover induced by ovariectomy, such as an increase in the osteoclastic surface (Oc.S/BS), number of osteoclasts per mm bone surface (N.Oc/BS), mineralized surface per mm bone surface (MS/BS), and bone mineral apposition rate (MAR). A significant decrease in the bone volume (BV/TV) observed in ovx was not modulated by a 3-day infusion of rmIL-4 prior to sacrifice. In sham, rmIL-4 also caused a significant decrease in the Oc.S/BS, N.Oc/BS, MS/BS, and MAR, but the BV/TV was not modulated by rmIL-4. We conclude that short term infusion of rmIL-4 in vivo rapidly inhibits not only bone resorption but also its formation in both sham-operated and ovariectomized growing mice, resulting in a low rate of bone turnover without modulating bone volume.


Assuntos
Desenvolvimento Ósseo/efeitos dos fármacos , Remodelação Óssea/efeitos dos fármacos , Interleucina-4/farmacologia , Osteoclastos/efeitos dos fármacos , Fosfatase Alcalina/sangue , Aminoácidos/urina , Animais , Densidade Óssea/efeitos dos fármacos , Ensaio de Imunoadsorção Enzimática , Estradiol/administração & dosagem , Estradiol/farmacologia , Feminino , Fêmur/efeitos dos fármacos , Humanos , Interleucina-6/sangue , Interleucina-6/urina , Camundongos , Ovariectomia , Proteínas Recombinantes/farmacologia
18.
Bone ; 26(3): 255-61, 2000 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10709998

RESUMO

Growth hormone (GH) exerts potent effects on bone metabolism, resulting in an increased bone formation in animals and humans. Acromegaly has been associated with increased bone turnover, whereas the net effect of the increased bone metabolism has been obscured because patients with acromegaly are often associated with hypogonadism. We investigated changes in cortical and cancellous bone in adult rats implanted mammosomatotrophic pituitary tumor cells (GH3) as a model of acromegaly with gonadal dysfunction. Acromegaly model rats were prepared by implanting GH3 cells into female Wistar-Furth rats at 17 weeks of age. At 28 weeks of age, GH3-bearing rats (GH rats) showed very high serum GH levels and a moderate increase in serum prolactin levels, resulting in low circulating estradiol levels. The GH rats showed significant increases in body weight and in length and volume of both the femur and vertebral body. Bone mineral content values of either the midfemur or the whole lumbar body were significantly greater in the GH rats compared with littermate controls, while the areal bone mineral density values of the respective bones were not different between the two groups. The parameters of mechanical strength of the femur were significantly larger in the GH rats than in controls, whereas those of the lumbar vertebral body cylinder specimen were not different between the two groups. Respective normalized mechanical parameters of the femur and the vertebral body were the same in the GH rats as in controls. In the midfemur, the GH rats showed a significant increase in the total cross-sectional area without influencing the bone marrow area, resulting in an increase in the cortical bone area and the moment of inertia compared with controls. The indices of periosteal bone formation in the midfemur were greater in the GH rats compared with controls, but the endocortical bone formation and resorption were not different between the two groups. In the vertebral body cancellous bone, the GH rats had an increase in bone turnover rate, whereas the structural parameters were not different between the two groups. These results from GH3-bearing rats demonstrate that an excess of GH increases cortical bone mass in rats accompanied with estrogen deficiency, while no large effect on vertebral body cancellous bone mass is seen.


Assuntos
Acromegalia/etiologia , Osso e Ossos/patologia , Neoplasias Hipofisárias/patologia , Animais , Peso Corporal , Feminino , Hiperprolactinemia/complicações , Hipogonadismo/etiologia , Neoplasias Hipofisárias/complicações , Ratos , Ratos Wistar
19.
J Nucl Med ; 28(7): 1115-22, 1987 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-3598702

RESUMO

Follow-up examinations to determine the frequency of thyroidal disorders were conducted by the Radiation Effects Research Foundation (RERF) on individuals in Hiroshima and Nagasaki who were less than 20 yr of age at the time of exposure to the atomic bomb. Concentrations of serum thyroid stimulating hormone (TSH), thyroglobulin (TG), and anti-TG antibody 30 yr after exposure were also determined. Nontoxic uninodular goiter was found in 13 cases of the 100 + rad exposed group (n = 477) and in three cases of the nonexposed group (n = 501). The prevalence in the 100+ rad exposed group was significantly higher (chi-squared = 6.584, p less than 0.01). Thyroid cancer was found in eight exposed cases, all of whom were in the 100+ rad group, and the prevalence was significantly greater (chi-squared = 7.919, p less than 0.01). Regardless of the presence or absence of thyroid disorders, serum TSH and TG levels were not statistically different between the 100 rad + exposed and nonexposed groups. Although hypothyroidism was found in 23 of the total cases, there was no correlation between its development and exposure to ionizing irradiation.


Assuntos
Guerra Nuclear , Lesões por Radiação/sangue , Tireoglobulina/sangue , Doenças da Glândula Tireoide/sangue , Tireotropina/sangue , Adolescente , Feminino , Seguimentos , Bócio Nodular/sangue , Bócio Nodular/etiologia , Humanos , Japão , Masculino , Neoplasias Induzidas por Radiação/sangue , Lesões por Radiação/etiologia , Doenças da Glândula Tireoide/etiologia , Neoplasias da Glândula Tireoide/sangue , Neoplasias da Glândula Tireoide/etiologia
20.
J Nucl Med ; 27(9): 1475-9, 1986 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-3528414

RESUMO

We developed a new ultrasonic scanner for the thyroid and, in this study, the estimated volumes of the thyroids by this scanner were compared with the weights of those obtained at operation. In this ultrasonic scanner, an annular array transducer was employed instead of the conventional single element concave transducer. The distance of the focused area by this transducer was as long as 5 cm compared to 1 cm by the conventional transducer; therefore, the image obtained by the new scanner was so clear that it was not difficult to draw accurately the outlines of the thyroids. The volumes of the thyroids were calculated by a computerized digitizer. The estimated volumes of the thyroids by the ultrasonic scanner were closely correlated with their weights calculated by adding the actual weights of the thyroids removed to the estimates of the thyroids left at operation. Their correlation coefficients were as high as 0.99. This suggests that this new ultrasonic scanner is very useful in the determination of the volumes of the thyroids, since the measurement is very accurate, simple, and reproducible.


Assuntos
Glândula Tireoide/anatomia & histologia , Ultrassonografia , Adenoma/patologia , Adulto , Idoso , Feminino , Doença de Graves/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Valores de Referência , Glândula Tireoide/patologia , Neoplasias da Glândula Tireoide/patologia , Ultrassonografia/instrumentação , Ultrassonografia/métodos
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA