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1.
Diabet Med ; 32(2): 213-9, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25255697

RESUMEN

AIM: To analyse the effects of thyroid hormones on ß-cell function and glucose metabolism in people with prediabetes who are euthyroid. METHODS: A total of 111 people who were euthyroid underwent 75-g oral glucose tolerance tests, of whom 52 were assigned to the normal glucose tolerance and 59 to the prediabetes groups. Homeostatic model assessment of ß-cell function, insulinogenic index and areas under the curve for insulin and glucose were evaluated as indices of pancreatic ß-cell function. RESULTS: In both groups, BMI, fasting insulin, homeostasis model assessment ratio and HDL cholesterol correlated significantly with all indices of pancreatic ß-cell function. Free triiodothyronine correlated positively with all insulin secretion indices in the prediabetes group. Multiple linear regression analysis showed that free triiodothyronine was an independent variable that had a positive correlation with all indices of ß-cell function in the prediabetes group. By contrast, no such correlation was found in the normal glucose tolerance group. CONCLUSIONS: Free triiodothyronine is associated with both basal and glucose-stimulated insulin secretion in people with prediabetes who are euthyroid; therefore, the regulation of insulin secretion by thyroid hormones is a potentially novel therapeutic target for the treatment of diabetes.


Asunto(s)
Células Secretoras de Insulina/metabolismo , Insulina/metabolismo , Estado Prediabético/fisiopatología , Glándula Tiroides/metabolismo , Triyodotironina/metabolismo , Regulación hacia Arriba , Adulto , Anciano , Índice de Masa Corporal , HDL-Colesterol/sangre , Femenino , Prueba de Tolerancia a la Glucosa , Humanos , Insulina/sangre , Resistencia a la Insulina , Secreción de Insulina , Masculino , Persona de Mediana Edad , Sobrepeso/complicaciones , Estado Prediabético/sangre , Estado Prediabético/complicaciones , Estado Prediabético/metabolismo , Índice de Severidad de la Enfermedad , Solubilidad , Triyodotironina/sangre , Triyodotironina/química
2.
Bone ; 187: 117203, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39019130

RESUMEN

INTRODUCTION: We performed consecutive checkups of the 1964 Tokyo Olympic contestants every 4 years for 50 years. This study evaluated bone mineral density (BMD) and its related factors in former Tokyo Olympic athletes. OBJECTIVES: The study population comprised 181 former Olympians (141 men and 40 women) who had undergone BMD measurement in at least one of the four checkups performed every 4 years since 2005. The mean age of the 104 subjects who participated in the last checkup in 2016 was 76.1 years for men and 74.0 years for women. METHODS: Health-related information regarding medical history, regular physical activity, alcohol consumption, and smoking was obtained using questionnaires. The areal BMD of the total body was measured using dual-energy X-ray absorptiometry (DXA). The relationship between BMD and anthropometric measurements, medical history, and health behaviors was examined. Furthermore, we assessed the influence of the mode and magnitude of weight-bearing and impact loading during athletic events during their active careers on BMD. RESULTS: The mean Z-scores of BMD of the total body, lumbar spine, pelvis, and upper and lower limbs were > 0 in both male and female subjects at each checkup. The subjects had a higher mean height and weight than the Japanese age- and sex-matched individuals. Furthermore, the subjects had higher grip strength than the age- and sex-matched individuals. BMD showed a positive correlation with body weight, lean body mass (LBM), muscle mass, and grip strength, with higher correlation coefficients found between BMD of the pelvis or lower limbs and LBM or muscle mass volume. When the association with current participation in sports activities was examined, male subjects who exercised weekly had significantly higher grip strength and greater muscle mass volume; however, no significant differences were observed among female subjects. After adjusting for age and LMB, BMD was significantly higher in both the lumbar spine and lower limbs of male subjects with relatively more impact loading in sports events during their active careers. CONCLUSION: The Tokyo Olympic contestants maintained a high muscle mass even at an older age, regardless of their medical history, which may be one of the reasons for their ability to maintain a high BMD.


Asunto(s)
Atletas , Densidad Ósea , Humanos , Densidad Ósea/fisiología , Masculino , Femenino , Anciano , Tokio , Deportes/fisiología , Persona de Mediana Edad , Absorciometría de Fotón , Japón , Pueblos del Este de Asia
3.
J Cell Biol ; 154(5): 1069-79, 2001 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-11535623

RESUMEN

Evidence is provided that proteolytic cleavage of collagen type IV results in the exposure of a functionally important cryptic site hidden within its triple helical structure. Exposure of this cryptic site was associated with angiogenic, but not quiescent, blood vessels and was required for angiogenesis in vivo. Exposure of the HUIV26 epitope was associated with a loss of alpha1beta1 integrin binding and the gain of alphavbeta3 binding. A monoclonal antibody (HUIV26) directed to this site disrupts integrin-dependent endothelial cell interactions and potently inhibits angiogenesis and tumor growth. Together, these studies suggest a novel mechanism by which proteolysis contributes to angiogenesis by exposing hidden regulatory elements within matrix-immobilized collagen type IV.


Asunto(s)
Colágeno/metabolismo , Neoplasias/patología , Neovascularización Patológica , Neovascularización Fisiológica , Animales , Anticuerpos Monoclonales/metabolismo , Anticuerpos Monoclonales/farmacología , Anticuerpos Monoclonales/uso terapéutico , Membrana Basal/química , Membrana Basal/metabolismo , Sitios de Unión , Adhesión Celular/fisiología , Movimiento Celular/fisiología , Embrión de Pollo , Colágeno/química , Colágeno/inmunología , Neovascularización de la Córnea/inducido químicamente , Retinopatía Diabética/metabolismo , Retinopatía Diabética/patología , Endotelio Vascular/metabolismo , Epítopos/metabolismo , Humanos , Metaloproteinasa 2 de la Matriz/genética , Metaloproteinasa 2 de la Matriz/metabolismo , Melanoma/irrigación sanguínea , Melanoma/patología , Ratones , Microscopía Fluorescente , Trasplante de Neoplasias , Neoplasias/tratamiento farmacológico , Neoplasias/metabolismo , Péptido Hidrolasas/metabolismo , Unión Proteica , Desnaturalización Proteica , Estructura Terciaria de Proteína , Ratas , Receptores de Vitronectina/metabolismo , Vasos Retinianos/metabolismo , Piel/irrigación sanguínea , Piel/metabolismo , Células Tumorales Cultivadas
4.
Hum Gene Ther ; 12(10): 1311-21, 2001 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-11440624

RESUMEN

Retinal and choroidal neovascularization are the most frequent causes of severe and progressive vision loss. Studies have demonstrated that Tie2, an endothelial-specific receptor tyrosine kinase, plays a key role in angiogenesis. In this study, we determined whether adenovirus-mediated gene delivery of extracellular domain of the Tie2 receptor (ExTek) could inhibit experimental retinal and choroidal neovascularization. Immunofluorescence histochemistry with a monoclonal antibody to human Tie2 showed that Tie2 expression is prominent around and within the base of newly formed blood vessels of retinal and choroidal neovascular lesions. A single intramuscular injection of adenovirus expressing ExTek genes achieved plasma levels of ExTek exceeding 500 microg/ml in mice for 10 days (in neonates) and 7 days (in adults). This treatment inhibited retinal neovascularization by 47% (p < 0.05) in a murine model of ischemia-induced retinopathy. The same treatment reduced the incidence and extent of sodium fluorescein leakage from choroidal neovascular lesions by 52% (p < 0.05) and 36% (p < 0.01), respectively, in a laser-induced murine choroidal neovascularization model. The same mice showed a 45% (p < 0.001) reduction of integrated area of the choroidal neovascularization. These findings indicate that Tie2 signaling is a common component of the angiogenic pathway in both retinal and choroidal neovascularization, providing a potentially useful target in the treatment of intraocular neovascular diseases.


Asunto(s)
Inhibidores de la Angiogénesis/farmacología , Coroides/irrigación sanguínea , Terapia Genética/métodos , Proteínas de Neoplasias/genética , Neovascularización Patológica , Proteínas Proto-Oncogénicas , Vasos Retinianos/metabolismo , Adenoviridae/genética , Factores de Edad , Animales , Fluoresceína/farmacología , Isquemia , Ratones , Microscopía Fluorescente , Proteínas de Neoplasias/sangre , Proteínas de Neoplasias/química , Estructura Terciaria de Proteína , Receptor TIE-2 , Transducción de Señal , Factores de Tiempo
5.
Invest Ophthalmol Vis Sci ; 37(13): 2678-85, 1996 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-8977482

RESUMEN

PURPOSE: To determine whether a reporter gene can be introduced into rat and mouse retinas in vivo using the authors' novel liposome system. METHODS: Cytomegalovirus-promoted LacZ genes and nonhistone nuclear protein, high mobility group 1 (HMG1), were coencapsulated in liposomes by agitation and sonication. The liposomes were then coated with the envelope of inactivated hemagglutinating virus of Japan (HVJ; Sendai virus) by fusion (HVJ liposome). The HVJ liposome solution was injected into the vitreous cavity of adult Sprague-Dawley rats (n = 30) or the subretinal space of adult CD-1 mice (n = 42). LacZ expression was assessed by beta-galactosidase assay. RESULTS: LacZ expression was demonstrated in the photoreceptors as long as 30 days after intravitreal and subretinal injections. beta-Gal activity was observed also in neurons and glial cells in the ganglion cell layer of the intravitreally injected rats and, although at lower intensity, in the retinal pigment epithelium of both animals. No inflammation or toxic effects secondary to the HVJ liposomes were detected on histologic examination. CONCLUSIONS: In vivo transfer and expression of a reporter gene into adult mammalian retina can be achieved using HVJ liposomes. This method offers a promise as a nonviral system for in vivo gene transfer into adult mammalian neural retina.


Asunto(s)
Técnicas de Transferencia de Gen , Operón Lac/genética , Retina/enzimología , beta-Galactosidasa/metabolismo , Animales , Citomegalovirus/genética , Expresión Génica , Proteínas del Grupo de Alta Movilidad/genética , Técnicas para Inmunoenzimas , Inyecciones , Liposomas , Masculino , Ratones , Virus de la Parainfluenza 1 Humana/genética , Ratas , Ratas Sprague-Dawley , Retina/virología , Cuerpo Vítreo
6.
Invest Ophthalmol Vis Sci ; 39(3): 509-16, 1998 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-9501860

RESUMEN

PURPOSE: To evaluate the feasibility of introducing exogenous genes and phosphorothioate oligonucleotides into the anterior chamber tissues of rats and monkeys using the authors' fusogenic liposomes. METHODS: Hemagglutinating virus of Japan liposomes containing LacZ DNA-high-mobility group 1 complexes or fluorescein isothiocyanate (FITC)-labeled phosphorothioate oligonucleotides were prepared and injected into the anterior chambers of rats (3 microliters) and rhesus monkeys (30 microliters). The expression of LacZ DNA was visualized histochemically by beta-Galactosidase assay and was followed for as long as 60 days in rats and 30 days in monkeys. FITC-labeled phosphorothioate oligonucleotides were observed by fluorescence microscopy for as long as 14 days in rats and 7 days in monkeys. RESULTS: Injection of LacZ DNA-high-mobility group 1 complexes encapsulated in hemagglutinating virus of Japan liposomes resulted in blue staining in the trabecular meshwork and iris-ciliary body of rats and selectively in the trabecular meshwork of monkeys at the concentrations used. This LacZ expression lasted for as long as 14 days after injection in both animals. Phosphorothioate oligonucleotides (3 microM) also were introduced into the rat trabecular meshwork and iris-ciliary body and into the primate trabecular meshwork when encapsulated in hemagglutinating virus of Japan liposomes, although the injection of naked FITC-labeled phosphorothioate oligonucleotides at the same concentration resulted in little fluorescence in any anterior chamber tissue. CONCLUSIONS: This study shows that the use of hemagglutinating virus of Japan liposomes can transfer LacZ DNA and phosphorothioate oligonucleotides to adult rat and primate trabecular meshwork. This system may enable progress in glaucoma research and in the development of nonviral somatic gene therapy of the trabecular meshwork to treat glaucoma.


Asunto(s)
ADN/metabolismo , Operón Lac/genética , Respirovirus/genética , Tionucleótidos/genética , Malla Trabecular/metabolismo , Transfección , Animales , Cuerpo Ciliar/metabolismo , Fluoresceína-5-Isotiocianato , Técnicas para Inmunoenzimas , Iris/metabolismo , Liposomas , Macaca mulatta , Masculino , Microscopía Fluorescente , Oligonucleótidos/genética , Oligonucleótidos/metabolismo , Ratas , Ratas Sprague-Dawley , Respirovirus/metabolismo , Malla Trabecular/virología , beta-Galactosidasa/metabolismo
7.
Invest Ophthalmol Vis Sci ; 36(3): 571-8, 1995 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-7890488

RESUMEN

PURPOSE: To determine in rats whether there are time-dependent changes in interleukin-1 alpha (IL-1 alpha) and interleukin-1 beta (IL-1 beta) gene expression in transient retinal ischemia and to localize their mRNAs in the retina. METHODS: Retinal ischemia was induced in Sprague-Dawley rats by ligating the optic nerve. Two hours later, the ligature was released and reperfusion occurred. The levels of IL-1 alpha and IL-1 beta gene expression in the sensory retina were then compared at various times after reperfusion by a semiquantitative polymerase chain reaction method. Localization of their expressed mRNAs was examined by in situ hybridization histochemistry. RESULTS: Little expression of IL-1 alpha and IL-1 beta genes was observed in normal retina. IL-1 alpha gene expression rapidly increased (about 30-fold greater than that of the control) as early as 1 hour after cessation of ischemia, reached a peak (about 50-fold) at 3 to 12 hours, and then gradually decreased to near baseline levels. IL-1 beta gene expression began to increase 2 hours later than did that of IL-1 alpha and had two peaks. IL-1 beta gene was found by in situ hybridization histochemistry to be expressed by retinal glial cells, endothelial cells, and neutrophils infiltrating the retina and vitreous. No gene expression was found in the control retinas. CONCLUSIONS: Expression of IL-1 alpha and IL-1 beta genes was dramatically upregulated during reperfusion after induced retinal ischemia. IL-1 beta gene was expressed by retinal glial cells, endothelial cells, and neutrophils recruited into the retina. From these results, it appeared that IL-1 may have an important role in retinal ischemia-reperfusion injury.


Asunto(s)
Interleucina-1/biosíntesis , Isquemia/metabolismo , Vasos Retinianos/metabolismo , Animales , Secuencia de Bases , Cartilla de ADN , Endotelio/metabolismo , Expresión Génica , Hibridación in Situ , Interleucina-1/genética , Isquemia/patología , Masculino , Datos de Secuencia Molecular , Neuroglía/metabolismo , Neutrófilos/metabolismo , ARN Mensajero/biosíntesis , Ratas , Ratas Sprague-Dawley , Retina/metabolismo , Vasos Retinianos/patología
8.
Invest Ophthalmol Vis Sci ; 35(3): 1107-13, 1994 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-8125721

RESUMEN

PURPOSE: To localize and determine the levels of interleukin-1 alpha (IL-1 alpha), interleukin-1 beta (IL-1 beta), and tumor necrosis factor (TNF) gene expression in the process of endotoxin-induced uveitis (EIU) in rats. METHOD: EIU was induced by lipopolysaccharide (LPS) injection in male Lewis rats weighing 150 to 200 g. The levels of IL-1 alpha, IL-1 beta, and TNF gene expression in the iris-ciliary body (ICB) were quantified by a semiquantitative polymerase chain reaction (PCR) method; in situ hybridization histochemistry was carried out to localize the gene transcripts. RESULTS: Little expression of IL-1 alpha, IL-1 beta, and TNF genes was observed in normal ICB. IL-1 alpha gene expression began to increase (about 10-fold greater than that of the control) as early as 1 hour after the LPS treatment, reached a peak (about 100-fold) at 3 to 6 hours. A second peak (60-fold) was observed at 24 hours, and the expression returned to near basal levels (3-fold) at 48 hours. Expression of IL-1 beta and TNF genes showed a pattern similar to that of IL-1 alpha. Three hours after LPS treatment, IL-1 beta and TNF genes were found by in situ hybridization histochemistry to be expressed by "histiocyte-like" cells in the stroma of the ICB. None of these genes were detected in the control rats. CONCLUSIONS: Expression of IL-1 alpha, IL-1 beta, and TNF genes was dramatically up-regulated in the process of EIU. These genes were found to be expressed in "histiocyte-like" cells in the ICB, and may have an important role in EIU.


Asunto(s)
Interleucina-1/metabolismo , Factor de Necrosis Tumoral alfa/metabolismo , Uveítis Anterior/metabolismo , Animales , Toxinas Bacterianas , Secuencia de Bases , Cuerpo Ciliar/metabolismo , Cartilla de ADN , Endotoxinas , Enterotoxinas , Expresión Génica , Hibridación in Situ , Interleucina-1/genética , Iris/metabolismo , Masculino , Datos de Secuencia Molecular , Reacción en Cadena de la Polimerasa , Ratas , Ratas Endogámicas Lew , Salmonella , Factor de Necrosis Tumoral alfa/genética , Regulación hacia Arriba , Uveítis Anterior/inducido químicamente , Uveítis Anterior/patología
9.
Invest Ophthalmol Vis Sci ; 37(5): 826-32, 1996 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-8603867

RESUMEN

PURPOSE: The authors previously reported that in vitro treatment with N(G)-nitro L-arginine (L-NNA), an inhibitor of nitric oxide synthase (NOS), reduces aqueous humor (AH) protein and cellular infiltration in endotoxin-induced uveitis in the rat eye. The objective of the current study was to determine the role(s) of respective major forms (constitutive and inducible) of NOS by comparing the effects of relatively selective inhibitors of these NOS isozymes. METHODS: N(G)-nitro L-arginine (L-NNA), a relatively selective inhibitor for constitutive NOS (c-NOS), and N-iminoethyl L-ornithine (L-NIO), a more selective inhibitor for inducible NOS (i-NOS), were administered in vivo. Male Lewis rats were footpad injected with bacterial lipopolysaccharide (LPS, 200 microgram) and were injected intraperitoneally at 0 hours, 6 hours, or both, after LPS injection with 10 mg of NIO, NNA, or saline as a control. Nitric oxide synthase activity in the ocular tissue and AH protein and cell content were determined at various times after treatment with LPS. RESULTS: After in vivo treatment, L-NIO was found to be a more potent inhibitor than L-NNA for ocular i-NOS (87% versus 43% inhibition), and L-NNA was more potent than L-NIO for ocular c-NOS (81% versus 39%). Two injections of L-NNA, one at time 0 and one 6 hours after LPS injection, inhibited the AH protein increase by 71%, but L-NIO did so by only 30%. L-NNA inhibited cellular infiltration by 86%, whereas L-NIO had no significant effect on cellular infiltration. A significant inhibition of cellular infiltration and AH protein increase also was observed with a single injection of 10 mg of L-NNA but not of L-NIO when the inhibitors were given simultaneously with LPS. Thus, reduction of uveitis symptoms correlates with the inhibition of c-NOS. CONCLUSIONS: The constitutive form of NOS in ocular tissue, presumably in vascular endothelial cells, appears to play a critical role at the onset of the development of endotoxin-induced uveitis.


Asunto(s)
Isoenzimas/fisiología , Óxido Nítrico Sintasa/fisiología , Uveítis Anterior/enzimología , Animales , Humor Acuoso/enzimología , Arginina/análogos & derivados , Arginina/farmacología , Recuento de Células , Modelos Animales de Enfermedad , Endotelio Vascular/efectos de los fármacos , Endotelio Vascular/enzimología , Inhibidores Enzimáticos/farmacología , Isoenzimas/antagonistas & inhibidores , Lipopolisacáridos , Masculino , Óxido Nítrico Sintasa/antagonistas & inhibidores , Nitroarginina , Ornitina/análogos & derivados , Ornitina/farmacología , Fagocitos/efectos de los fármacos , Fagocitos/enzimología , Ratas , Ratas Endogámicas Lew , Salmonella , Uveítis Anterior/inducido químicamente
10.
Invest Ophthalmol Vis Sci ; 40(2): 450-8, 1999 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-9950605

RESUMEN

PURPOSE: Nitric oxide is a reactive species that could be protective or destructive to the retina depending on the stage of the evolving ischemic process. This study was conducted to obtain a better understanding of the roles of constitutive nitric oxide synthase (cNOS) during reperfusion after ischemia in rat retina. METHODS: Retinal ischemia was induced for 60 minutes in Sprague-Dawley rats by ligating the optic nerve. Gene expression for endothelial and neuronal nitric oxide synthases (eNOS and nNOS) was studied by reverse transcription-polymerase chain reaction (RT-PCR). To inhibit cNOS, NG-nitro-L-arginine (L-NNA) was injected intraperitoneally four times (every 6 hours) beginning 2 hours after reperfusion, for a total dose of 80 mg/kg. Retinal damage was assessed by the rate of a- and b-wave recovery on electroretinograms and by the thickness of the retinal layers. Retinal circulation and vessel diameter were evaluated by the dye-dilution technique. RESULTS: After ischemia ended, eNOS mRNA initially decreased until 6 hours, then increased to a peak at 12 hours, and decreased progressively beyond 24 hours until the final measurement at 96 hours of reperfusion. nNOS mRNA decreased to nearly undetectable levels during the same measurement periods. L-NNA treatment enhanced reduction of a- and b-wave amplitudes and increased thinning of the inner retina in postischemic eyes. Retinal mean circulation time was markedly prolonged in L-NNA-treated postischemic eyes. Arterial mean transit times were 2.1-fold and 4.5-fold longer in L-NNA-treated postischemic eyes than in L-NNA-treated nonischemic eyes and in D-NNA-treated postischemic eyes, respectively. CONCLUSIONS: This study shows that postischemic inhibition of NOS worsens retinal damage after ischemia-reperfusion and alters postischemic retinal circulation. Nitric oxide may play an important role in protecting the retina from ischemic injury, possibly by preventing postischemic hypoperfusion.


Asunto(s)
Óxido Nítrico Sintasa/metabolismo , Daño por Reperfusión/enzimología , Enfermedades de la Retina/enzimología , Vasos Retinianos/enzimología , Animales , Cartilla de ADN/química , Electrorretinografía , Inhibidores Enzimáticos/farmacología , Angiografía con Fluoresceína , Expresión Génica , Procesamiento de Imagen Asistido por Computador , Masculino , Óxido Nítrico Sintasa/antagonistas & inhibidores , Óxido Nítrico Sintasa/genética , Óxido Nítrico Sintasa de Tipo I , Óxido Nítrico Sintasa de Tipo III , Nitroarginina/farmacología , ARN Mensajero/metabolismo , Ratas , Ratas Sprague-Dawley , Daño por Reperfusión/patología , Enfermedades de la Retina/patología , Vasos Retinianos/efectos de los fármacos , Vasos Retinianos/patología , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
11.
Invest Ophthalmol Vis Sci ; 40(8): 1783-91, 1999 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-10393049

RESUMEN

PURPOSE: To identify the expression of chondroitin/dermatan sulfate proteoglycan decorin in retina and to elucidate its changes during development and ischemia-reperfusion. METHODS: Expression of decorin in rat retina was investigated by reverse transcription-polymerase chain reaction (RT-PCR) and immunohistochemistry. Distributional changes during development and transient ischemia in model eyes also were investigated by immunohistochemical experiments. RESULTS: Gene expression of decorin core protein was identified in rat retina by RT-PCR. Decorin immunoreactivities were shown throughout the retina, especially in the ganglion cell layer. In developing rat retinas, at embryonic stages (embryonic day 16), decorin was distributed uniformly throughout the retina. As retina matured, the intensity of decorin immunostaining in retinal inner layers and retinal pigment epithelium increased. Furthermore, in experimental transient retinal ischemia, after transient downregulation of the decorin core protein gene between 24 and 48 hours after the ischemia, recovered (or increased) expression was shown by semiquantitative RT-PCR experiments. Immunohistochemical studies revealed strong decorin immunoreactivities in the damaged inner layers 1 week later. CONCLUSIONS: The expression of decorin was identified in adult and developing rat retina. The distributional changes of decorin during the retinal development suggest that this proteoglycan may play a role in the differentiation of retinal ganglion cells. Moreover, in rat ischemia-reperfusion models, the alterations in gene expression and immunohistochemical localization showed the contribution of this proteoglycan to the damage and repair processes in diseased retina.


Asunto(s)
Proteoglicanos/metabolismo , Retina/metabolismo , Animales , Western Blotting , Cartilla de ADN/química , Decorina , Proteínas de la Matriz Extracelular , Femenino , Expresión Génica , Técnicas para Inmunoenzimas , Masculino , Embarazo , Proteoglicanos/genética , ARN Mensajero/metabolismo , Ratas , Ratas Wistar , Daño por Reperfusión/genética , Daño por Reperfusión/metabolismo , Retina/embriología , Retina/crecimiento & desarrollo , Enfermedades de la Retina/genética , Enfermedades de la Retina/metabolismo , Vasos Retinianos/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
12.
Invest Ophthalmol Vis Sci ; 41(8): 2309-17, 2000 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-10892878

RESUMEN

PURPOSE: To determine the antiangiogenic effects of peroxisome proliferator-activated receptor (PPAR)-gamma agonists on ocular cells involved in the pathogenesis of choroidal neovascularization (CNV) in vitro and on experimental laser photocoagulation-induced CNV in vivo. METHODS: PPAR-gamma expression in human retinal pigment epithelial (RPE) cells and bovine choroidal endothelial cells (CECs) was determined using an RNase protection assay and Western blot analysis. Two PPAR-gamma ligands, troglitazone (TRO) and rosiglitazone (RSG; 0.1-20 microM), were used to assess effects on RPE and CEC proliferation and migration and CEC tube formation in response to vascular endothelial growth factor (VEGF). The effects of intravitreal injection of TRO on laser photocoagulation-induced CNV lesions in rat eyes (15 experimental, 15 control, nine burns per eye) and cynomolgus monkey eyes (two experimental, two control, seven paramacular burns per eye) was assessed by fluorescein angiography and histologic evaluation. RESULTS. PPAR-gamma1 was expressed in both RPE and CEC. PPAR-gamma ligands significantly inhibited VEGF-induced migration and proliferation in both cell types and tube formation of CEC in a dose-response manner. CNV in rats was markedly inhibited by intravitreous injection of TRO (P < 0.001). Lesions showed significantly less fluorescein leakage and were histologically thinner in the TRO-treated animals. Similar findings were present in the TRO-treated lesions in two monkey eyes. The drug showed no apparent adverse effects in the adjacent retina or in control eyes. CONCLUSIONS: The inhibition of VEGF-induced choroidal angiogenesis in vitro, and CNV in vivo by PPAR-gamma ligands suggests the potential application of these agents in the large group of patients with age-related macular degeneration complicated by CNV.


Asunto(s)
Neovascularización Coroidal/prevención & control , Cromanos/farmacología , Receptores Citoplasmáticos y Nucleares/metabolismo , Tiazoles/farmacología , Tiazolidinedionas , Factores de Transcripción/metabolismo , Animales , Western Blotting , División Celular/efectos de los fármacos , Movimiento Celular/efectos de los fármacos , Coroides/irrigación sanguínea , Coroides/efectos de los fármacos , Coroides/patología , Neovascularización Coroidal/etiología , Neovascularización Coroidal/patología , Cromanos/administración & dosificación , Relación Dosis-Respuesta a Droga , Factores de Crecimiento Endotelial/toxicidad , Endotelio Vascular/metabolismo , Angiografía con Fluoresceína , Humanos , Inyecciones , Coagulación con Láser , Ligandos , Linfocinas/toxicidad , Macaca fascicularis , Masculino , Epitelio Pigmentado Ocular/metabolismo , Ratas , Ratas Endogámicas BN , Receptores Citoplasmáticos y Nucleares/agonistas , Rosiglitazona , Tiazoles/administración & dosificación , Factores de Transcripción/agonistas , Troglitazona , Factor A de Crecimiento Endotelial Vascular , Factores de Crecimiento Endotelial Vascular
13.
Invest Ophthalmol Vis Sci ; 39(12): 2474-8, 1998 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-9804157

RESUMEN

PURPOSE: To determine the feasibility of experimental gene transfer to laser-induced choroidal neovascular membrane (CNVM) in rats, with a retroviral vector containing the reporter construct beta-galactosidase (beta-gal). METHODS: Laser photocoagulation was used to induce CNVM in rats. To ascertain the duration of beta-gal expression in the CNVM, 23 rats received 10 burns (75 microm, 100 mW, 0.1 seconds) in their right eyes, and beta-gal expression was examined from day 3 to 4 months. In addition, 14 pigmented rats were treated with 3 photocoagulation burns in their right eyes. beta-gal vector was injected into the vitreous or subretinal space 2 days later. On day 14, fluorescein angiography was performed to detect choroidal neovascularization. Then, beta-gal expression in each photocoagulation-induced CNVM was examined by observing the exposed fundus of the eyes stained with the beta-gal substrate X-Gal. RESULTS: beta-gal expression was identified in the CNVM induced by photocoagulation from day 5 (16.2% +/- 6.8% of the lesions) to 4 months (3.7% +/- 2.4%). Histopathologic examination revealed beta-gal-transduced macrophages and spindle-shaped cells, which amounted to 1.12% +/- 0.58% (at 2 weeks) of the total cells in the CNVM. beta-gal expression was restricted to the CNVM, and there was no beta-gal transduction in surrounding normal retinochoroidal tissue. There was no correlation between choroidal neovascularization formation and beta-gal expression. CONCLUSIONS: The feasibility of gene transduction targeted to the photocoagulation-induced CNVM was demonstrated using retroviral vectors. By transducing functional genes, this model could be useful for investigating the possibility of gene therapy to inhibit formation of the CNVM in age-related macular degeneration.


Asunto(s)
Neovascularización Coroidal/enzimología , Técnicas de Transferencia de Gen , Coagulación con Láser/efectos adversos , Retroviridae/genética , beta-Galactosidasa/genética , Animales , Neovascularización Coroidal/etiología , Neovascularización Coroidal/patología , Angiografía con Fluoresceína , Terapia Genética , Vectores Genéticos , Histocitoquímica , Masculino , Ratas , Ratas Endogámicas BN , beta-Galactosidasa/metabolismo
14.
Invest Ophthalmol Vis Sci ; 42(7): 1617-25, 2001 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-11381069

RESUMEN

PURPOSE: To determine whether vascular endothelial growth factor (VEGF) regulates angiopoietin (Ang)-1 and -2 expression in retinal pigment epithelial (RPE) cells. METHODS: Expression of VEGF, Ang1, and Ang2 in surgically removed human choroidal neovascular membranes (CNVMs) was analyzed by double-label confocal immunofluorescence microscopy. Total RNA was extracted from cultured human RPE cells treated with VEGF for mRNA analysis. Northern blot analysis was performed to examine the time course and dose response of Ang1 and Ang2 mRNA expression. mRNA stability and nuclear run-on analyses were performed. Secreted Ang1 and Ang2 protein levels in conditioned media from RPE cells were examined by Western blot analysis. RESULTS: Ang1 and Ang2 immunostaining colocalized with VEGF-positive stromal cells in human CNVMS: Ang1 and Ang2 mRNAs were expressed by cultured serum-starved RPE cells. VEGF upregulated Ang1 mRNA in a time- and dose-dependent manner without a significant change in Ang2 mRNA. Ang1 and Ang2 mRNAs in RPE cells were as stable as that of S18. VEGF stimulation further increased the half-life of Ang1 mRNA, but did not alter its transcription rate. VEGF increased the amount of Ang1, but not Ang2, protein secreted into the medium. CONCLUSIONS: The colocalization of Ang1 and Ang2 with VEGF in CNVM stromal cells and the upregulation of Ang1 expression by VEGF in cultured RPE cells suggest that VEGF may selectively modulate Ang expression during CNV.


Asunto(s)
Factores de Crecimiento Endotelial/farmacología , Linfocinas/farmacología , Glicoproteínas de Membrana/metabolismo , Epitelio Pigmentado Ocular/efectos de los fármacos , Angiopoyetina 1 , Angiopoyetina 2 , Northern Blotting , Western Blotting , Células Cultivadas , Neovascularización Coroidal/metabolismo , Relación Dosis-Respuesta a Droga , Factores de Crecimiento Endotelial/genética , Factores de Crecimiento Endotelial/metabolismo , Inhibidores Enzimáticos/metabolismo , Técnica del Anticuerpo Fluorescente Indirecta , Expresión Génica , Humanos , Linfocinas/genética , Linfocinas/metabolismo , Glicoproteínas de Membrana/genética , Microscopía Confocal , Persona de Mediana Edad , Epitelio Pigmentado Ocular/metabolismo , Proteínas/genética , Proteínas/metabolismo , ARN Mensajero/metabolismo , Factores de Tiempo , Regulación hacia Arriba/efectos de los fármacos , Factor A de Crecimiento Endotelial Vascular , Factores de Crecimiento Endotelial Vascular
15.
Invest Ophthalmol Vis Sci ; 40(2): 273-9, 1999 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-9950584

RESUMEN

PURPOSE: To evaluate the abilities of recombinant adenovirus carrying the basic fibroblast growth factor (bFGF) gene to (1) produce bFGF protein in vitro and (2) rescue retinal photoreceptors in Royal College of Surgeons (RCS) rats in vivo. METHODS: Cultured human retinal pigment epithelial cells were infected with one of the following two replication-deficient adenoviral vectors that drive inserted genes by beta-actin promoter with cytomegalovirus enhancer: AxCAJSbFGF, which expresses the human bFGF gene, and AxCAlacZ, carrying the cDNA of bacterial beta-galactosidase as a viral control. These viruses and recombinant bFGF protein were also injected into the subretinal space of RCS rats at the age of 21 days. The production of bFGF was evaluated by an immunohistochemical method in vitro and in vivo. The secretion of bFGF produced in vitro was quantified by an enzyme-linked immunosorbent assay. The thickness of the outer nuclear layer (ONL) as a marker of photoreceptor cell rescue was estimated at 2, 28, and 56 days after the injections. RESULTS: AxCAJSbFGF produced human bFGF protein effectively both in vitro and in vivo. The semiquantitative analysis of ONL thickness revealed a significant protective effect of AxCAJSbFGF and the recombinant bFGF protein injection up to 56 days after injection. CONCLUSIONS: These results demonstrate that a recombinant adenoviral vector can achieve the transfer of bFGF gene in vitro and have a protective effect for photoreceptor cells in vivo. Gene therapy with a bFGF-expressing recombinant adenoviral vector may provide a new strategy with which to target retinal degenerative diseases.


Asunto(s)
Adenoviridae/genética , Factor 2 de Crecimiento de Fibroblastos/biosíntesis , Expresión Génica , Células Fotorreceptoras de Vertebrados/fisiología , Degeneración Retiniana/metabolismo , Animales , Supervivencia Celular , Células Cultivadas , Virus Defectuosos , Ensayo de Inmunoadsorción Enzimática , Factor 2 de Crecimiento de Fibroblastos/genética , Técnica del Anticuerpo Fluorescente Indirecta , Galactósidos/metabolismo , Técnicas de Transferencia de Gen , Terapia Genética , Vectores Genéticos , Histocitoquímica , Indoles/metabolismo , Células Fotorreceptoras de Vertebrados/patología , Epitelio Pigmentado Ocular/virología , Ratas , Ratas Mutantes , Degeneración Retiniana/patología , Degeneración Retiniana/terapia , beta-Galactosidasa/metabolismo
16.
Arch Ophthalmol ; 116(3): 342-8, 1998 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-9514488

RESUMEN

OBJECTIVES: To determine the fate of phosphorothioate oligonucleotides (S-ODNs), which are commonly used for antisense strategy, in murine retina in vivo with the use of fluorescein isothiocyanate (FITC)-labeled S-ODNs, and to evaluate our fusogenic liposome system that may facilitate the delivery of S-ODNs. METHODS: The FITC-labeled S-ODNs were encapsulated in liposomes, which were then coated with the envelope of inactivated hemagglutinating virus of Japan (HVJ; Sendai virus) by fusion (HVJ liposomes). Intravitreal injection of naked FITC-labeled S-ODNs or of the HVJ liposomes was done in ICR mice. After fixation, cryosections and flat-mounted retinas were prepared and examined by fluorescence microscopy. RESULTS: Injection of naked FITC-labeled S-ODNs at 3 micromol/L exhibited weak fluorescence in 13% of the cells in the ganglion cell layer. When the concentration was increased to 30 micromol/L, high fluorescence was seen in 59% of cells in the ganglion cell layer at this time. This fluorescence diminished within a day. In contrast, injection of HVJ liposomes containing FITC-labeled S-ODNs at 3 micromol/L resulted in high fluorescence in 44% of the cells in the ganglion cell layer at 1 hour, and this fluorescence lasted for up to 3 days. This treatment also resulted in high fluorescence within retinal vessel walls, and weak fluorescence in photoreceptor cells. CONCLUSIONS: Intravitreally injected S-ODNs were rapidly eliminated from neural retina, and the use of HVJ liposomes could improve the delivery of S-ODNs. This method may be a potentially useful system for the antisense-based therapies for retinal diseases.


Asunto(s)
Sistemas de Liberación de Medicamentos , Oligonucleótidos Antisentido/farmacocinética , Células Ganglionares de la Retina/metabolismo , Tionucleótidos/farmacocinética , Animales , Fluoresceína-5-Isotiocianato , Colorantes Fluorescentes , Inyecciones , Liposomas , Masculino , Ratones , Ratones Endogámicos ICR , Oligonucleótidos Antisentido/administración & dosificación , Respirovirus , Tionucleótidos/administración & dosificación , Proteínas Virales de Fusión/farmacocinética , Cuerpo Vítreo
17.
Arch Ophthalmol ; 115(6): 752-6, 1997 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-9194727

RESUMEN

OBJECTIVE: To identify molecular mechanisms of retinal responses to intraocular pressure elevation in primate experimental glaucoma. METHODS: An experimental glaucoma model was created by repeated laser trabeculophotocoagulation. After the preparation of complementary DNAs from extracted total RNAs in the retinas, polymerase chain reaction (PCR) experiments were performed for the following screening target genes: beta-tubulin beta 2 and beta 5 and glial fibrillary acidic protein (GFAP). To investigate the amplified sequences derived from the PCR experiments, sequencing, subcloning, and Southern blot analysis of PCR products were performed. In addition, an immunohistochemical analysis was performed in an attempt to show the distribution of the target gene products in the retinas. RESULTS: A series of PCR experiments suggested up-regulation of gene expression for GFAP but not for beta-tubulins. Sequencing of the PCR products and results of the Southern blot analysis showed that the amplified sequences were derived mainly from the target gene, GFAP, and that increased expression of GFAP was found despite the severity of glaucoma. Immunohistochemical studies also demonstrated increased expression of GFAP proteins in Müller cells and astrocytes in the retinas of primate eyes with experimental glaucoma. CONCLUSIONS: Our study showed up-regulation of GFAP at gene and protein levels, which suggests that glial components in the retina may contribute to the pathologic processes induced by elevated intraocular pressure.


Asunto(s)
Glaucoma/genética , Proteína Ácida Fibrilar de la Glía/genética , Retina/fisiopatología , Animales , Southern Blotting , Expresión Génica , Glaucoma/metabolismo , Glaucoma/fisiopatología , Proteína Ácida Fibrilar de la Glía/metabolismo , Inmunohistoquímica , Presión Intraocular , Macaca , Reacción en Cadena de la Polimerasa , Retina/metabolismo , Transcripción Genética
18.
Arch Ophthalmol ; 116(12): 1629-32, 1998 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-9869793

RESUMEN

OBJECTIVE: To investigate the localization of N epsilon-(carboxymethyl)lysine (CML), a component and major immunologic epitope of advanced glycation end products, in aged eyes and choroidal neovascular membranes (CNVMs) surgically excised from eyes with age-related macular degeneration. METHODS: Immunohistochemistry for CML was performed using 8 snap-frozen, surgically excised CNVMs. Twelve eyes from patients aged 69 to 82 years and 2 donor eyes, 1 each from a 23-week-old fetus and 21-year-old patient, without age-related macular degeneration or diabetic retinopathy were also examined. To determine if retinal pigment epithelial cells in CNVMs accumulate advanced glycation end products, cytokeratin and CML were stained in paired serial sections. RESULTS: Soft, macular drusen and/or basal laminar and basal linear deposits were observed in 8 of 12 aged eyes. Each case showed CML accumulation, while overlying retinal pigment epithelial cells showed no accumulation in all 12 eyes. In CNVMs, however, retinal pigment epithelial cells showed CML accumulation in their cytoplasm. CONCLUSION: The additional accumulation of advanced glycation end products in soft, macular drusen and/or retinal pigment epithelial cells may play a role in the pathogenesis of CNVM formation in age-related macular degeneration. CLINICAL RELEVANCE: Recently, advanced glycation end products have been found to play a role both in aging changes and neovascularization. Localization of advanced glycation end products in the above-mentioned tissue may lead to a better understanding of the pathogenesis of age-related macular degeneration.


Asunto(s)
Neovascularización Coroidal/metabolismo , Productos Finales de Glicación Avanzada/metabolismo , Lisina/análogos & derivados , Degeneración Macular/metabolismo , Adulto , Anciano , Anciano de 80 o más Años , Neovascularización Coroidal/etiología , Neovascularización Coroidal/patología , Humanos , Técnicas para Inmunoenzimas , Queratinas/metabolismo , Lisina/metabolismo , Degeneración Macular/complicaciones , Epitelio Pigmentado Ocular/metabolismo
19.
J Cataract Refract Surg ; 22(5): 601-6, 1996 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-8784634

RESUMEN

PURPOSE: To compare the results of a triple procedure using either extracapsular cataract extraction (ECCE) or one of two phacoemulsification techniques combined with trabeculotomy ab externo and intraocular lens (IOL) implantation. SETTING: Kyoto University Hospital, Kyoto, Japan, and Nagata Eye Hospital, Nara, Japan. METHODS: In this comparative study, 25 eyes with primary open-angle glaucoma had ECCE combined with trabeculotomy ab externo and IOL implantation and 22 had the same procedure using phacoemulsification instead of ECCE. Of the eyes that had phacoemulsification, 10 had a single-flap and 12 had a double-flap procedure. RESULTS: All 22 eyes that had phacoemulsification had a postoperative IOP of 21 mm Hg or less, as did all ECCE eyes except 2. Although the self-sealing incision might have caused the higher incidence of IOP spikes in the immediate postoperative period, IOPs in the phacoemulsification groups were lower after 3 months. Results were similar in the single-flap and double-flap phacoemulsification groups. There were no significant complications. CONCLUSION: Cataract extraction by phacoemulsification or ECCE combined with IOL implantation and trabeculotomy ab externo is a safe, effective treatment for patients with coexisting glaucoma and cataract.


Asunto(s)
Glaucoma de Ángulo Abierto/cirugía , Lentes Intraoculares , Facoemulsificación/métodos , Trabeculectomía/métodos , Anciano , Catarata/complicaciones , Femenino , Estudios de Seguimiento , Glaucoma de Ángulo Abierto/complicaciones , Humanos , Presión Intraocular , Masculino , Complicaciones Posoperatorias , Resultado del Tratamiento , Agudeza Visual
20.
Curr Eye Res ; 18(5): 321-6, 1999 May.
Artículo en Inglés | MEDLINE | ID: mdl-10372992

RESUMEN

PURPOSE: To test the ability of a mutant herpes simplex virus (HSV) hrR3 to inhibit growth of Y79 human retinoblastoma in vitro and in vivo. METHODS: Cultured Y79 cells were infected with multiplicities of infection (MOI) ranging from 0.004 to 0.1 of hrR3. Surviving cells were counted using trypan blue dye exclusion. Using X-gal staining, expression of the lacZ gene was examined in vitro on day 3 postinfection to evaluate viral replication. Nude mice harboring Y79 tumors subcutaneously received an intraneoplasmic injection of 5 x 10(7) plaque-forming units of hrR3. The tumor sizes were measured weekly. Expression of the lacZ gene was also examined on one week postinfection. RESULTS: There are 31% and 13% cells surviving in cultured Y79 cells infected by hrR3 at an MOI of 0.1 on days 3 and 5 postinfection respectively compared to those of mock-infected cells. Also more than 70% of Y79 cells were stained with X-gal at an MOI of 0.1 which demonstrated active viral replication in vitro. Virus-treated subcutaneous tumors were smaller than control tumors (p<<0.05, Student's t-test) on days 14, 21, and 28 postinfection. Positive X-gal staining was also observed in the tumor nodule which was challenged with this viral vector. CONCLUSIONS: We have demonstrated that hrR3 is capable of inhibiting Y79 tumor growth both in cell culture and in nude mice. These data suggest that gene therapy using this mutant HSV vector can be a new supplementary therapeutic modality for retinoblastoma.


Asunto(s)
Mutación/fisiología , Neoplasias de la Retina/patología , Neoplasias de la Retina/virología , Retinoblastoma/patología , Simplexvirus/genética , Animales , Supervivencia Celular/fisiología , Histocitoquímica , Humanos , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Neoplasias de la Retina/metabolismo , Retinoblastoma/metabolismo , Retinoblastoma/virología , Células Tumorales Cultivadas , beta-Galactosidasa/metabolismo
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