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1.
Endocr J ; 71(3): 253-264, 2024 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-38143085

RESUMEN

Maintenance of islet function after in vitro culture is crucial for both transplantation and research. Here we evaluated the effects of encapsulation in alginate fiber on the function of human islets which were distributed by the Alberta Islet Distribution Program. Encapsulated human islets from 15 deceased donors were cultured under 5.5 or 25 mM glucose conditions in vitro. The amounts of C-peptide and glucagon secreted from encapsulated islets into the culture media were measured periodically, and immunohistochemical studies were performed. Encapsulated islets maintained C-peptide and glucagon secretion for more than 75 days in 5 cases; in two cases, their secretion was also successfully detected even on day 180. α- and ß-cell composition and ß-cell survival in islets were unaltered in the fiber after 75 or 180 days of culture. The encapsulated islets cultured with 5.5 mM glucose, but not those with 25 mM glucose, exhibited glucose responsiveness of C-peptide secretion until day 180. We demonstrate that alginate encapsulation enabled human islets to maintain their viability and glucose responsiveness of C-peptide secretion after long-term in vitro culture, potentially for more than for 180 days.


Asunto(s)
Trasplante de Islotes Pancreáticos , Islotes Pancreáticos , Humanos , Glucagón/farmacología , Péptido C , Alginatos/farmacología , Glucosa/farmacología , Insulina/farmacología
2.
Heliyon ; 9(9): e19972, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37809993

RESUMEN

Human pluripotent stem cell (hPSCs) derived-pancreatic islets (hSC-islets) are good candidates for cell replacement therapy for patients with diabetes as substitutes for deceased donor-derived islets, because they are pluripotent and have infinite proliferation potential. Grafted hSC-islets ameliorate hyperglycemia in diabetic mice; however, several weeks are needed to normalize the hyperglycemia. These data suggest hSC-islets require maturation, but their maturation process in vivo is not yet fully understood. In this study, we utilized two kinds of streptozotocin (STZ)-induced diabetes model mice by changing the administration timing in order to examine the time course of maturation of hSC-islets and the effects of hyperglycemia on their maturation. We found no hyperglycemia in immune-compromised mice when hSC-islets had been transplanted under their kidney capsules in advance, and STZ was administered 4 weeks after transplantation. Of note, the blood glucose levels of those mice were stably maintained under 100 mg/dl 10 weeks after transplantation; this is lower than the mouse glycemic set point (120-150 mg/dl), suggesting that hSC-islets control blood glucose levels to the human glycemic set point. We confirmed that gene expression of maturation markers of pancreatic beta cells tended to upregulate during 4 weeks after transplantation. Periodical histological analysis revealed that revascularization was observed as early as 1 week after transplantation, but reinnervation in the grafted hSC-islets was not detected at all, even 15 weeks after transplantation. In conclusion, our hSC-islets need at least 4 weeks to mature, and the human glycemic set point is a good index for evaluating ultimate maturity for hSC-islets in vivo.

3.
Microbiol Spectr ; 10(6): e0349022, 2022 12 21.
Artículo en Inglés | MEDLINE | ID: mdl-36314907

RESUMEN

We newly generated two human induced pluripotent stem cell (hiPSC)-derived spheroid lines, termed Spheroids_4MACE2-TMPRSS2 and Spheroids_15M63ACE2-TMPRSS2, both of which express angiotensin-converting enzyme 2 (ACE2) and transmembrane protease serine 2 (TMPRSS2), which are critical for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Both spheroids were highly susceptible to SARS-CoV-2 infection, and two representative anti-SARS-CoV-2 agents, remdesivir and 5h (an inhibitor of SARS-CoV-2's main protease), inhibited the infectivity and replication of SARS-CoV-2 in a dose-dependent manner, suggesting that these human-derived induced spheroids should serve as valuable target cells for the evaluation of anti-SARS-CoV-2 activity. IMPORTANCE The hiPSC-derived spheroids we generated are more expensive to obtain than the human cell lines currently available for anti-SARS-CoV-2 drug evaluation, such as Calu-3 cells; however, the spheroids have better infection susceptibility than the existing human cell lines. Although we are cognizant that there are human lung (and colonic) organoid models for the study of SARS-CoV-2, the production of those organoids is greatly more costly and time consuming than the generation of human iPSC-derived spheroid cells. Thus, the addition of human iPSC-derived spheroids for anti-SARS-CoV-2 drug evaluation studies could provide the opportunity for more comprehensive interpretation of the antiviral activity of compounds against SARS-CoV-2.


Asunto(s)
Células Madre Pluripotentes Inducidas , SARS-CoV-2 , Humanos , Enzima Convertidora de Angiotensina 2 , COVID-19 , Evaluación de Medicamentos , Células Madre Pluripotentes Inducidas/metabolismo , SARS-CoV-2/efectos de los fármacos , Serina
4.
PLoS One ; 16(1): e0245204, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33428669

RESUMEN

Diabetes mellitus is caused by breakdown of blood glucose homeostasis, which is maintained by an exquisite balance between insulin and glucagon produced respectively by pancreatic beta cells and alpha cells. However, little is known about the mechanism of inducing glucagon secretion from human alpha cells. Many methods for generating pancreatic beta cells from human pluripotent stem cells (hPSCs) have been reported, but only two papers have reported generation of pancreatic alpha cells from hPSCs. Because NKX6.1 has been suggested as a very important gene for determining cell fate between pancreatic beta and alpha cells, we searched for the factors affecting expression of NKX6.1 in our beta cell differentiation protocols. We found that BMP antagonism and activation of retinoic acid signaling at stage 2 (from definitive endoderm to primitive gut tube) effectively suppressed NKX6.1 expression at later stages. Using two different hPSCs lines, treatment with BMP signaling inhibitor (LDN193189) and retinoic acid agonist (EC23) at Stage 2 reduced NKX6.1 expression and allowed differentiation of almost all cells into pancreatic alpha cells in vivo after transplantation under a kidney capsule. Our study demonstrated that the cell fate of pancreatic cells can be controlled by adjusting the expression level of NKX6.1 with proper timing of BMP antagonism and activation of retinoic acid signaling during the pancreatic differentiation process. Our method is useful for efficient induction of pancreatic alpha cells from hPSCs.


Asunto(s)
Proteínas Morfogenéticas Óseas/metabolismo , Células Secretoras de Glucagón/metabolismo , Células Madre Pluripotentes Inducidas/metabolismo , Transducción de Señal/efectos de los fármacos , Tretinoina/farmacología , Animales , Línea Celular , Células Secretoras de Glucagón/trasplante , Xenoinjertos , Humanos , Masculino , Ratones , Ratones Endogámicos NOD , Ratones SCID
5.
Regen Ther ; 11: 65-72, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31193869

RESUMEN

INTRODUCTION: Although immunosuppressants are required for current islet transplantation for type 1 diabetic patients, many papers have already reported encapsulation devices for islets to avoid immunological attack. The aim of this study is to determine the optimal number of cells and optimal transplantation site for human iPS-derived islet-like cells encapsulated in alginate fiber using diabetic model mice. METHODS: We used a suspension culture system for inducing islet-like cells from human iPS cells throughout the islet differentiation process. Islet-like spheroids were encapsulated in the alginate fiber, and cell transplantation experiments were performed with STZ-induced diabetic NOD/SCID mice. We compared the efficacy of transplanted cells between intraperitoneal and subcutaneous administration of alginate fibers by measuring blood glucose and human C-peptide levels serially in mice. Grafts were analyzed histologically, and gene expression in pancreatic ß cells was also compared. RESULTS: We demonstrated the reversal of hyperglycemia in diabetic model mice after intraperitoneal administration of these fibers, but not with subcutaneous ones. Intraperitoneal fibers were easily retrieved without any adhesion. Although we detected human c-peptide in mice plasma after subcutaneous administration of these fibers, these fibers became encased by fibrous tissue. CONCLUSIONS: These results suggest that the intraperitoneal space is favorable for islet-like cells derived from human iPS cells when encapsulated in alginate fiber.

6.
Int J Dev Biol ; 63(6-7): 271-280, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31250910

RESUMEN

Human pluripotent stem cells (hPSCs), such as embryonic stem cells (ESCs) and induced pluripotent stem cells (iPSCs), are very attractive cell sources for the treatment of diabetes mellitus, because numerous cells can be obtained using their infinite proliferation potential to overcome the paucity of donor islets. Advances in differentiation protocols make it possible to generate glucose responsive hPSC-beta cells, which can ameliorate hyperglycemia in diabetic mice. These protocols have mainly been based on an adherent culture system. However, in clinical applications, suspension culture methods are more suitable for large-scale culture. There are reports that suspension culture and spheroid formation promote differentiation in various cell types, including hPSCs, but, to our knowledge, there are no reports comparing gene expression patterns between suspension and adherent cultured human iPSCs (hiPSCs) during definitive endoderm (DE) differentiation. In this study, we chose several stage marker genes, not only for DE but also for posterior epiblast and primitive streak, and we examined their time course expression in suspension and adherent cultures by quantitative PT-PCR (qPCR), western blot, flow cytometry and immunocytochemistry. Our results demonstrate that expressions of these marker genes are faster and more strongly induced in suspension culture than in adherent culture during the DE differentiation process, indicating that suspension culture favors DE differentiation.


Asunto(s)
Adhesión Celular , Diferenciación Celular , Células Madre Embrionarias/citología , Endodermo/citología , Células Madre Pluripotentes Inducidas/citología , Esferoides Celulares/citología , Técnicas de Cultivo de Célula , Células Cultivadas , Células Madre Embrionarias/metabolismo , Endodermo/metabolismo , Humanos , Células Madre Pluripotentes Inducidas/metabolismo , Esferoides Celulares/metabolismo
7.
PLoS One ; 14(5): e0217110, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31145732

RESUMEN

Maturity-onset diabetes of the young (MODY) is a heterozygous monogenic diabetes; more than 14 disease genes have been identified. However, the pathogenesis of MODY is not fully understood because the patients' pancreatic beta cells are inaccessible. To elucidate the pathology of MODY, we established MODY3 patient-derived iPS (MODY3-iPS) cells using non-integrating Sendai virus (SeV) vector and examined the mutant mRNA and protein of HNF1A (Hepatocyte Nuclear factor 1A) after pancreatic lineage differentiation. Our patient had a cytosine insertion in the HNF1A gene (P291fsinsC) causing frameshift and making a premature termination codon (PTC). We confirmed these MODY3-iPS cells possessed the characteristics of pluripotent stem cells. After we differentiated them into pancreatic beta cells, transcripts of HNF1A gene were cloned and sequenced. We found that P291fsinsC mutant transcripts were much less frequent than wild ones, but they increased after adding cycloheximide (CHX) to the medium. These results suggested that mutant mRNA was destroyed by nonsense-mediated mRNA decay (NMD). Moreover, we were not able to detect any band of mutant proteins in pancreatic lineage cells which were differentiated from MODY3-iPSCs by western blot (WB) analysis. A scarcity of the truncated form of mutant protein may indicate that MODY3 might be caused by a haplo-insufficiency effect rather than a dominant negative manner.


Asunto(s)
Diabetes Mellitus Tipo 2/metabolismo , Factor Nuclear 1-alfa del Hepatocito/metabolismo , Células Madre Pluripotentes Inducidas/patología , Células Secretoras de Insulina/patología , Mutación , ARN Mensajero/genética , Células Cultivadas , Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/patología , Femenino , Haploinsuficiencia , Factor Nuclear 1-alfa del Hepatocito/genética , Humanos , Células Madre Pluripotentes Inducidas/metabolismo , Células Secretoras de Insulina/metabolismo , ARN Mensajero/metabolismo
8.
Regen Ther ; 10: 69-76, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-30623004

RESUMEN

INTRODUCTION: To complement islet transplantation for type1 diabetic patients, cell-based therapy using pluripotent stem cells such as ES cells and iPS cells is promising. Many papers have already reported the induction of pancreatic ß cells from these cell types, but a suspension culture system has not usually been employed. The aim of this study is to establish a suspension culture method for inducing functional islet-like cells from human iPS cells. METHODS: We used 30 ml spinner type culture vessels for human iPS cells throughout the differentiation process. Differentiated cells were analyzed by immunostaining and C-peptide secretion. Cell transplantation experiments were performed with STZ-induced diabetic NOD/SCID mice. Blood human C-peptide and glucagon levels were measured serially in mice, and grafts were analyzed histologically. RESULTS: We obtained spherical pancreatic beta-like cells from human iPS cells and detected verifiable amounts of C-peptide secretion in vitro. We demonstrated reversal of hyperglycemia in diabetic model mice after transplantation of these cells, maintaining non-fasting blood glucose levels along with the human glycemic set point. We confirmed the secretion of human insulin and glucagon dependent on the blood glucose level in vivo. Immunohistological analysis revealed that grafted cells became α, ß and δ cells in vivo. CONCLUSIONS: These results suggest that differentiated cells derived from human iPS cells grown in suspension culture mature and function like pancreatic islets in vivo.

9.
Invest Ophthalmol Vis Sci ; 59(5): 1844-1854, 2018 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-29677344

RESUMEN

Purpose: To explore interactions between pilocarpine and the ROCK inhibitor, ripasudil, on IOP and pupil diameter in human eyes, and morphological and functional changes in outflow tissues in vitro. Methods: IOP and pupil diameter were measured after pilocarpine and/or ripasudil, which were topically applied in healthy subjects. Human trabecular meshwork (HTM) cells were used in a gel contraction assay, for the evaluation of phosphorylation of myosin light chain and cofilin, and immunostaining for cytoskeletal proteins. Porcine ciliary muscle (CM) was used in a CM contraction assay. The permeability of human Schlemm's canal endothelial (SCE) cells was evaluated by measuring transendothelial electrical resistance and fluorescein permeability. Results: Both pilocarpine and ripasudil significantly reduced IOP in human eyes, but pilocarpine interfered with ripasudil-induced IOP reduction when concomitantly introduced. Ripasudil significantly inhibited gel contraction, TGFß2-induced stress fiber formation, α-smooth muscle actin expression, and phosphorylation of both myosin light chain and cofilin in HTM cells. Pilocarpine reduced these effects, significantly inhibited the ripasudil-induced HTM cell responses to TGFß2 stimulation, and increased the permeability in SCE cells. In CM, ripasudil inhibited pilocarpine-stimulated contraction, but ripasudil did not have significant effects on pilocarpine-induced miosis. Conclusions: Pilocarpine interfered with the direct effects of ROCK inhibitor on the conventional outflow pathway leading to IOP reduction and cytoskeletal changes in trabecular meshwork cells, but did not affect the relaxation effect of the ROCK inhibitor. It is therefore necessary to consider possible interference between these two drugs, which both affect the conventional outflow.


Asunto(s)
Humor Acuoso/fisiología , Presión Intraocular/efectos de los fármacos , Isoquinolinas/administración & dosificación , Pilocarpina/administración & dosificación , Pupila/efectos de los fármacos , Sulfonamidas/administración & dosificación , Malla Trabecular/efectos de los fármacos , Factores Despolimerizantes de la Actina/metabolismo , Administración Oftálmica , Adulto , Animales , Western Blotting , Interacciones Farmacológicas , Impedancia Eléctrica , Inhibidores Enzimáticos/administración & dosificación , Femenino , Voluntarios Sanos , Humanos , Macaca , Masculino , Persona de Mediana Edad , Agonistas Muscarínicos/administración & dosificación , Cadenas Ligeras de Miosina/metabolismo , Soluciones Oftálmicas , Fosforilación , Malla Trabecular/metabolismo , Quinasas Asociadas a rho/antagonistas & inhibidores
10.
Invest Ophthalmol Vis Sci ; 59(1): 21-30, 2018 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-29305605

RESUMEN

Purpose: Dexamethasone (Dex) regulates aqueous humor outflow by inducing reorganization of the cytoskeleton and extracellular matrix (ECM) production. Rho kinase (ROCK) has an important role in this process, but the upstream pathway leading to its activation remains elusive. The purpose of the study was to determine the role of autotaxin (ATX), an enzyme involved in the generation of lysophosphatidic acid (LPA), in the Dex-induced fibrotic response and ECM production in human trabecular meshwork (HTM) cells. Methods: The expression of ATX in specimens from glaucoma patients was investigated by immunohistochemistry. Regulation of ATX expression and the changes in actin cytoskeleton, ECM production, myosin light chain (MLC) and cofilin phosphorylation, ATX secretion, and lysophospholipase D (lysoPLD) activity induced by Dex treatment in HTM cells were determined by immunofluorescence, real-time quantitative PCR, immunoblot, and the two-site immunoenzymetric and lysoPLD assays. Results: Significant ATX expression was found in conventional outflow pathway specimens from glaucoma patients. Dex treatment induced increases in ATX mRNA levels, protein expression, and secretion in HTM cells in association with reorganization of cytoskeleton and ECM accumulation. Significant suppression of these aforementioned changes was observed after ATX/LPA-receptor/ROCK inhibition as well as suppression of fibrotic changes and MLC and cofilin phosphorylation in HTM cells. Conclusions: The results of this study, including the robust induction of ATX by Dex treatment, in association with fibrotic changes and ECM production in HTM cells, collectively suggest a potential role for ATX-LPA pathway in the regulation of aqueous humor outflow and IOP in glaucomatous eyes.


Asunto(s)
Dexametasona/farmacología , Proteínas de la Matriz Extracelular/biosíntesis , Regulación de la Expresión Génica , Glaucoma de Ángulo Abierto/genética , Hidrolasas Diéster Fosfóricas/genética , ARN/genética , Malla Trabecular/enzimología , Humor Acuoso/metabolismo , Western Blotting , Células Cultivadas , Fibrosis/inducido químicamente , Fibrosis/enzimología , Fibrosis/patología , Glaucoma de Ángulo Abierto/enzimología , Glaucoma de Ángulo Abierto/patología , Glucocorticoides/farmacología , Humanos , Inmunohistoquímica , Hidrolasas Diéster Fosfóricas/biosíntesis , Fosforilación , Reacción en Cadena en Tiempo Real de la Polimerasa , Transducción de Señal , Malla Trabecular/patología
11.
J Occup Health ; 59(1): 17-23, 2017 Jan 24.
Artículo en Inglés | MEDLINE | ID: mdl-27885245

RESUMEN

OBJECTIVES: Personal lifestyle, including diet, exercise, and sleep, might have an impact on work engagement, though previous studies have not focused on these relationships. The aim of this study was to examine whether dietary intake of fish, regular exercise, sufficient sleep, abstinence from alcohol, and abstinence from tobacco were positively associated with work engagement. METHODS: We recruited adults aged 40-74 years who attended the health checkups with a particular focus on the metabolic syndrome in central Tokyo. In December 2015, 797 people responded to a questionnaire and 592 (74.3%) who had regular jobs were selected for this study. Work engagement was assessed on the 9-item Utrecht Work Engagement Scale (UWES-9). Bivariate and multivariate regression analyses were performed to examine the relationships between lifestyle and UWES-9. RESULTS: Dietary intake of fish, regular exercise, sufficient sleep, and abstinence from tobacco were significantly correlated with the total UWES-9 score, even after adjusting for age, sex, and depressive and anxiety symptoms. The results suggested a dose-response relationship between dietary fish intake and work engagement. CONCLUSIONS: Dietary fish intake, regular exercise, sufficient sleep, and abstinence from tobacco might be lifestyle factors that can serve as resources for work engagement. These findings could be useful in motivating employees to make lifestyle improvements and convincing employers and managers that lifestyle is important not only for health but also for productivity.


Asunto(s)
Dieta/psicología , Ejercicio Físico/psicología , Estilo de Vida , Sueño , Trabajo/psicología , Adulto , Anciano , Consumo de Bebidas Alcohólicas , Animales , Estudios Transversales , Dieta/métodos , Eficiencia , Conducta Alimentaria/psicología , Femenino , Peces , Humanos , Masculino , Persona de Mediana Edad , Análisis de Regresión , Alimentos Marinos , Fumar , Encuestas y Cuestionarios , Tokio
12.
PLoS One ; 11(8): e0160985, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27532664

RESUMEN

PURPOSE: To determine the involvement of sympathetic activity in choroidal neovascularization (CNV) using laser-induced CNV in a mouse model. METHODS: We investigated changes in the proportions of intraocular lymphocytes, granulocytes, and three macrophage subtypes (Ly6Chi, Ly6Cint, and Ly6Clo) after laser injury in mice using flow cytometry, and evaluated CNV lesion size in mice lacking inflammatory cells. Further, we evaluated the lesion size in mice administered the ß3 receptor antagonist, splenic-denervated and splenectomized mice. We also assessed changes in the proportions of intraocular macrophages and peripheral blood monocytes in splenic-denervated and splenectomized mice. Lastly, lesion size was compared between splenic-denervated mice with or without adoptive transfer of macrophages following laser injury. After Ly5.1 mice spleen-derived Ly6Chi cells were transferred into Ly5.2 mice, the proportions of intraocular Ly5.1+Ly6Chi cells were compared. RESULTS: In WT mice, the proportion of CD4+ T cells recruited into the eye increased progressively from day 3 to day 7 after laser injury, whereas, intraocular CD8+ T cells did not change significantly. Proportions of B220+ cells, granulocytes, and two subtypes of intraocular macrophages (Ly6Chi and Ly6Clo) peaked at day 3 following laser injury. In contrast, Ly6Cint/loCD64+ subtype showed a significantly higher percentage at day 7 after laser injury. There were no differences in lesion size between CD4-/-or Rag2-/-mice and controls, whereas lesion size was significantly reduced in CCR2-/- mice and clodronate liposome-treated mice. CNV lesion area was significantly reduced in mice with ß3 blocker treatment, splenic-denervated and splenectomized mice compared with controls. Intraocular Ly6Chi macrophages were also reduced by splenic denervation or splenectomy. Adoptive transfer of spleen-derived Ly6Chi cells increased the lesion size in splenic-denervated mice. Compared with controls, intraocular donor-derived Ly6Chi cells recruited into the eye were reduced in splenic-denervated and splenectomized mice. CONCLUSIONS: Although lymphocytes had little effect on CNV formation, Ly6Chi macrophages/monocytes exacerbated CNV in mice. Sympathetic activity might contribute to CNV via the recruitment of macrophages to the eye.


Asunto(s)
Neovascularización Coroidal/prevención & control , Macrófagos/inmunología , Macrófagos/patología , Bazo/inmunología , Bazo/inervación , Traslado Adoptivo , Animales , Antígenos Ly/metabolismo , Movimiento Celular/inmunología , Neovascularización Coroidal/inmunología , Neovascularización Coroidal/patología , Modelos Animales de Enfermedad , Ojo/inmunología , Ojo/patología , Macrófagos/clasificación , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Receptores CCR2/deficiencia , Receptores CCR2/genética , Bazo/patología , Esplenectomía , Simpatectomía
13.
Invest Ophthalmol Vis Sci ; 57(2): 462-6, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26868748

RESUMEN

PURPOSE: Commercially available enzyme-linked immunosorbent assay (ELISA) kits are often used to monitor vascular endothelial growth factor (VEGF) levels in exudative age-related macular degeneration. To test their accuracy, this study performed measurements using the ELISA kits in the presence of anti-VEGF drugs. METHODS: The concentrations of bevacizumab, pegaptanib, or ranibizumab at 28 days and aflibercept at 28 and 56 days after an injection were estimated based on previous pharmacokinetic studies. Vascular endothelial growth factor concentrations were measured with two widely used VEGF ELISA kits in the presence of anti-VEGF drugs or control mouse immunoglobulin G (IgG). The monocyte chemotactic protein-1 (MCP-1) ELISA kit was used as a non-VEGF ELISA control kit. RESULTS: The concentrations of aflibercept, bevacizumab, pegaptanib, and ranibizumab were estimated at 0.14 to 7.2, 4.9, 8.6, and 0.11 to 1.1 µg/mL, respectively. ELISA underestimated the VEGF concentration 2- to 100-fold lower in the presence of an anti-VEGF drug, except for pegaptanib, at all VEGF concentrations tested (7.8-1500 pg/mL). Vascular endothelial growth factor at 1000 pg/mL was measured as 92, 150, and 170 pg/mL in the presence of aflibercept (7.2 µg/mL), bevacizumab (4.9 µg/mL), and ranibizumab (1.1 µg/mL), respectively (all P < 0.0001), and the measured VEGF concentration decreased proportionately by 90% to 92% with aflibercept, 85% to 94% with bevacizumab, and 83% to 99% with ranibizumab. The control mouse IgG did not interfere with the measurement of VEGF. Ranibizumab did not affect the measurements with MCP-1 ELISA. CONCLUSIONS: Investigators should exercise caution when interpreting measurements of VEGF ELISA in patients being treated with an anti-VEGF drug.


Asunto(s)
Inhibidores de la Angiogénesis/farmacología , Ensayo de Inmunoadsorción Enzimática/normas , Factor A de Crecimiento Endotelial Vascular/análisis , Inhibidores de la Angiogénesis/farmacocinética , Aptámeros de Nucleótidos/farmacocinética , Aptámeros de Nucleótidos/farmacología , Bevacizumab/farmacocinética , Bevacizumab/farmacología , Quimiocina CCL2/metabolismo , Semivida , Humanos , Inyecciones Intravítreas , Degeneración Macular/tratamiento farmacológico , Ranibizumab/farmacocinética , Ranibizumab/farmacología , Juego de Reactivos para Diagnóstico/normas , Receptores de Factores de Crecimiento Endotelial Vascular/farmacocinética , Receptores de Factores de Crecimiento Endotelial Vascular/farmacología , Proteínas Recombinantes de Fusión/farmacocinética , Proteínas Recombinantes de Fusión/farmacología , Reproducibilidad de los Resultados , Factor A de Crecimiento Endotelial Vascular/antagonistas & inhibidores , Cuerpo Vítreo/metabolismo
14.
Sci Rep ; 5: 15702, 2015 Oct 28.
Artículo en Inglés | MEDLINE | ID: mdl-26507897

RESUMEN

In early age-related macular degeneration (AMD), complement component C3 can be observed in drusen, which is the accumulation of material beneath the retinal pigment epithelium. The complement pathways, via the activation of C3, can upregulate the expression of cytokines and their receptors and the recruitment of inflammatory leukocytes, both of which play an important role in the development of choroidal neovascularization (CNV) in exudative AMD. Laser-induced CNV lesions were found to be significantly smaller in C3(-/-) mice than in wild-type mice. By using flow cytometry, we demonstrated that the proportions of intraocular granulocytes, CD11b(+)F4/80(+)Ly6C(hi) and CD11b(+)F4/80(+)Ly6C(lo) cells, were lower in C3(-/-) mice than in wild-type mice as early as day 1 after laser injury, and the proportions of granulocytes and three macrophage/monocyte subsets were significantly lower on day 3. In contrast, C3(-/-) mice had more granulocytes and CD11b(+)F4/80(+)Ly6C(hi) cells in peripheral blood than wild-type mice after injury. Further, the expression levels of Vegfa164 were upregulated in intraocular Ly6C(hi) macrophages/monocytes of C3(-/-) mice, but not as much as in wild-type mice. Collectively, our data demonstrate that despite a more pronounced induction of systemic inflammation, inhibition of complement factor C3 suppresses CNV by decreasing the recruitment of inflammatory cells to the lesion.


Asunto(s)
Neovascularización Coroidal/metabolismo , Neovascularización Coroidal/patología , Complemento C3/metabolismo , Inflamación/patología , Animales , Modelos Animales de Enfermedad , Granulocitos/metabolismo , Granulocitos/patología , Inflamación/metabolismo , Macrófagos/metabolismo , Macrófagos/patología , Degeneración Macular/metabolismo , Degeneración Macular/patología , Masculino , Ratones , Ratones Endogámicos C57BL , Monocitos/metabolismo , Monocitos/patología , Epitelio Pigmentado de la Retina/metabolismo , Epitelio Pigmentado de la Retina/patología
15.
Exp Eye Res ; 131: 77-83, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25576666

RESUMEN

As a part of the visual cycle, all-trans-retinol (all-trans-ROL), the major form of vitamin A in circulating blood, is transported to the retinal pigment epithelium (RPE). All-trans-ROL is essential for normal retina function. However, recent researches have shown that excessive retinol intake can cause increase of all-trans-retinal. This can lead to the accumulation of lipofuscin, which is important in the pathogenesis of retina degeneration disease, such as dry type age-related macular degeneration (AMD). Since there are few reports regarding the involvement of all-trans-ROL in exudative AMD, we investigated the effects of all-trans-ROL in vitro and in vivo. We evaluated vascular endothelial growth factor (VEGF) expression in ARPE-19 cells and THP-1 cells after all-trans-ROL treatment using ELISA and real-time RT-PCR. In-vitro tube formation assay was performed with HUVEC cells using the conditioned medium (CM) obtained from ARPE-19 cells treated with all-trans-ROL. Transcriptional activity of retinoic acid receptor (RAR) was evaluated using luciferase assay. In mice, VEGF expressions were investigated in the retina and RPE/choroid after three weeks of excessive oral retinol intake. Laser-induced choroidal neovascularization (CNV) models were evaluated after they were fed with various doses of retinol. VEGF mRNA expression and VEGF production were significantly increased in all-trans-ROL treated ARPE-19 cells, which were inhibited by an RAR antagonist LE540. In contrast, there were no significant changes in VEGF production in THP-1 cells. Transcriptional activity of RAR was upregulated by all-trans-ROL treatment in ARPE-19 cells. The CM, obtained from ARPE-19 cells treated with all-trans-ROL, induced more capillary-like tube formation than cells treated with control vehicles. In vivo, the high retinol diet group has increased VEGF expression in the RPE/choroid and larger lesion size was induced. Our results suggest that all-trans-ROL is a pro-angiogenic factor. Excessive retinoid intake may be a potential risk factor for exudative AMD.


Asunto(s)
Coroides/metabolismo , Neovascularización Coroidal/metabolismo , ARN/genética , Epitelio Pigmentado de la Retina/metabolismo , Regulación hacia Arriba , Factor A de Crecimiento Endotelial Vascular/genética , Vitamina A/farmacocinética , Animales , Coroides/efectos de los fármacos , Coroides/patología , Neovascularización Coroidal/tratamiento farmacológico , Neovascularización Coroidal/genética , Ensayo de Inmunoadsorción Enzimática , Humanos , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Epitelio Pigmentado de la Retina/efectos de los fármacos , Epitelio Pigmentado de la Retina/patología , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Factor A de Crecimiento Endotelial Vascular/biosíntesis , Vitaminas/farmacocinética
16.
Prim Care Diabetes ; 8(3): 207-14, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24529485

RESUMEN

AIMS: To investigate the effect of a computer-supported indirect-form lifestyle-modification program using Lifestyle Intervention Support Software for Diabetes Prevention (LISS-DP), as a clinically feasible strategy for primary prevention, on diet and physical activity habits in adults with a family history of type 2 diabetes. METHODS: This was a two-arm, randomized controlled trial: (1) lifestyle intervention (LI) group (n=70); (2) control (n=71). Healthy adults aged 30-60 years with a history of type 2 diabetes among their first-degree relatives were recruited. LI group received three times of lifestyle intervention using LISS-DP during six-month intervention period via mail. RESULTS: Lifestyle intervention group showed significantly greater decrease in energy intake six months after baseline, compared to control (-118.31 and -24.79 kcal/day, respectively, p=0.0099, Cohen's d=0.22), though the difference disappeared 1 year after from baseline. No difference was found in physical activity energy expenditure. CONCLUSIONS: A computer-based, non-face-to-face lifestyle intervention was effective on dietary habits, only during the intervention period. Further examination of the long-term effects of such intervention and physical activity is required.


Asunto(s)
Diabetes Mellitus Tipo 2/prevención & control , Conocimientos, Actitudes y Práctica en Salud , Educación del Paciente como Asunto/métodos , Conducta de Reducción del Riesgo , Programas Informáticos , Terapia Asistida por Computador , Actividades Cotidianas , Adulto , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/genética , Dieta/efectos adversos , Ingestión de Energía , Metabolismo Energético , Conducta Alimentaria , Femenino , Predisposición Genética a la Enfermedad , Humanos , Japón , Masculino , Persona de Mediana Edad , Actividad Motora , Folletos , Linaje , Factores de Riesgo , Factores de Tiempo , Resultado del Tratamiento
17.
Radiology ; 270(1): 282-91, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23962418

RESUMEN

PURPOSE: To determine if model-based iterative reconstruction (MBIR) can improve visualization of the Adamkiewicz artery on multi-detector row computed tomographic (CT) images compared with adaptive statistical iterative reconstruction (ASIR) and filtered back projection (FBP). MATERIALS AND METHODS: This retrospective study was approved by the institutional review board, and written informed consent for the CT examination was obtained. Thirty-three patients underwent contrast material-enhanced 64-section multi-detector row CT for assessment of aortic aneurysm or dissection. Helical data were reconstructed by using FBP, ASIR, and MBIR. The signal-to-noise ratio of the aorta and contrast-to-noise ratio of the anterior spinal artery relative to the spinal cord were measured on multiplanar reformatted images. Visualization of the Adamkiewicz artery and its continuity with the intercostal or lumbar artery were evaluated by using a four-point scale. All image analyses were performed by two blinded, independent observers. The one-way analysis of variance and the Wilcoxon signed-rank test were used for statistical analysis. RESULTS: MBIR showed significantly better signal-to-noise and contrast-to-noise ratios than did ASIR and FBP (P < .05 for all comparisons) with good interobserver agreement (intraclass correlation coefficient of 0.93 for signal-to-noise ratio and 0.75 for contrast-to-noise ratio). The visualization score of the Adamkiewicz artery was also significantly better when MBIR was used (3.4 ± 0.8 and 3.6 ± 0.7 for observers A and B, respectively) than when ASIR (2.7 ± 1.1 and 3.0 ± 1.0, respectively) or FBP (2.5 ± 1.2 and 3.1 ± 0.9, respectively) was used. CONCLUSION: Use of the MBIR algorithm led to improved multi-detector row CT visualization of the Adamkiewicz artery when compared with the use of ASIR and FBP.


Asunto(s)
Aneurisma de la Aorta/diagnóstico por imagen , Disección Aórtica/diagnóstico por imagen , Tomografía Computarizada por Rayos X/métodos , Adulto , Anciano , Anciano de 80 o más Años , Medios de Contraste , Femenino , Humanos , Yopamidol , Masculino , Persona de Mediana Edad , Interpretación de Imagen Radiográfica Asistida por Computador , Estudios Retrospectivos , Relación Señal-Ruido
18.
Chem Commun (Camb) ; 48(98): 11942-4, 2012 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-23073155

RESUMEN

We report a method for detecting microRNAs encapsulated in exosomes using a microelectrode array in semiconductor-based potentiometry after RT-PCR. The inherent miniaturization of the electrical biosensor meets requirements for massively parallel analysis of circulating microRNA as a noninvasive biomarker.


Asunto(s)
Técnicas Biosensibles , Exosomas/química , MicroARNs/análisis , MicroARNs/genética , Microelectrodos , Potenciometría , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Semiconductores
20.
Arch Intern Med ; 171(15): 1352-60, 2011 Aug 08.
Artículo en Inglés | MEDLINE | ID: mdl-21824948

RESUMEN

BACKGROUND: Previous studies demonstrated that intensive lifestyle modification can prevent type 2 diabetes mellitus among those with impaired glucose tolerance, but similar beneficial results have not been proved among those with impaired fasting glucose levels. We investigated the efficacy of lifestyle modification on type 2 diabetes incidence among those with impaired fasting glucose levels. METHODS: The present study was an unmasked, multicenter, randomized, controlled trial. A total of 641 overweight Japanese (aged 30-60 years) with impaired fasting glucose levels were recruited nationwide in Japan and randomly assigned to a frequent intervention group (n = 311) or a control group (n = 330). For 36 months after randomization, the frequent intervention group received individual instructions and follow-up support for lifestyle modification from the medical staff 9 times. The control group received similar individual instructions 4 times at 12-month intervals during the same period. The primary outcome was type 2 diabetes incidence in annual 75-g oral glucose tolerance tests, diagnosed according to World Health Organization criteria. RESULTS: There were no significant differences between the allocation groups in baseline characteristics and dropout rates. Estimated cumulative incidences of type 2 diabetes were 12.2% in the frequent intervention group and 16.6% in the control group. Overall, the adjusted hazard ratio in the frequent intervention group was 0.56 (95% confidence interval, 0.36-0.87). In the post hoc subgroup analyses, the hazard ratio reduced to 0.41 (95% confidence interval, 0.24-0.69) among participants with impaired glucose tolerance at baseline, and to 0.24 (0.12-0.48) among those with baseline hemoglobin A(1c) levels of 5.6% or more (the Japan Diabetes Society method). Such risk reduction was not observed among those with isolated impaired fasting glucose findings or baseline hemoglobin A(1c) levels of less than 5.6%. CONCLUSIONS: Lifestyle modifications can prevent type 2 diabetes among overweight Japanese with impaired fasting glucose levels. In addition, identifying individuals with more deteriorated glycemic status by using 75-g oral glucose tolerance test findings or, especially, measurement of hemoglobin A(1c) levels, could enhance the efficacy of lifestyle modifications. TRIAL REGISTRATION: umin.ac.jp/ctr Identifier: UMIN000001959.


Asunto(s)
Diabetes Mellitus Tipo 2/prevención & control , Intolerancia a la Glucosa/terapia , Estilo de Vida , Sobrepeso/terapia , Estado Prediabético/terapia , Adulto , Dieta Reductora , Ejercicio Físico , Conducta Alimentaria , Femenino , Humanos , Japón , Masculino , Persona de Mediana Edad
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