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1.
Cell Mol Life Sci ; 81(1): 314, 2024 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-39066814

RESUMO

This study examines the interplay between ambient temperature, brown adipose tissue (BAT) function, and bone metabolism, emphasizing the effects of cold exposure and BAT mitochondrial activity on bone health. Utilizing ovariectomized (OVX) mice to model primary osteoporosis and BAT-specific mitochondrial dysfunction (BKO) mice, we evaluated the impact of housing temperature on bone density, immune modulation in bone marrow, and the protective role of BAT against bone loss. Cold exposure was found to universally reduce bone mass, enhance osteoclastogenesis, and alter bone marrow T-cell populations, implicating the immune system in bone remodeling under cold stress. The thermogenic function of BAT, driven by mitochondrial oxidative phosphorylation, was crucial in protecting against bone loss. Impaired BAT function, through surgical removal or mitochondrial dysfunction, exacerbated bone loss in cold environments, highlighting BAT's metabolic role in maintaining bone health. Furthermore, cold-induced changes in BAT function led to systemic metabolic shifts, including elevated long-chain fatty acids, which influenced osteoclast differentiation and activity. These findings suggest a systemic mechanism connecting environmental temperature and BAT metabolism with bone physiology, providing new insights into the metabolic and environmental determinants of bone health. Future research could lead to novel bone disease therapies targeting these pathways.


Assuntos
Tecido Adiposo Marrom , Temperatura Baixa , Mitocôndrias , Osteoporose , Animais , Tecido Adiposo Marrom/metabolismo , Feminino , Camundongos , Mitocôndrias/metabolismo , Osteoporose/metabolismo , Osteoporose/patologia , Osteoclastos/metabolismo , Camundongos Endogâmicos C57BL , Densidade Óssea , Termogênese , Ovariectomia/efeitos adversos , Osso e Ossos/metabolismo , Osso e Ossos/patologia , Osteogênese
2.
Endocrinol Metab (Seoul) ; 39(3): 521-530, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38858821

RESUMO

BACKGRUOUND: Aging leads to sarcopenia, which is characterized by reduced muscle mass and strength. Many factors, including altered muscle protein turnover, diminished neuromuscular function, hormonal changes, systemic inflammation, and the structure and composition of muscle fibers, play a crucial role in age-related muscle decline. This study explored differences in muscle fiber types contributing to overall muscle function decline in aging, focusing on individuals with hip fractures from falls. METHODS: A pilot study at Chungnam National University Hospital collected muscle biopsies from hip fracture patients aged 20 to 80 undergoing surgical treatment. Muscle biopsies from the vastus lateralis and gluteus maximus were obtained during hip arthroplasty or internal fixation. Handgrip strength, calf and thigh circumference, and bone mineral density were evaluated in individuals with hip fractures from falls. We analyzed the relationships between each clinical characteristic and muscle fiber type. RESULTS: In total, 26 participants (mean age 67.9 years, 69.2% male) were included in this study. The prevalence of sarcopenia was 53.8%, and that of femoral and lumbar osteoporosis was 19.2% and 11.5%, respectively. Vastus lateralis analysis revealed an age-related decrease in type IIx fibers, a higher proportion of type IIa fibers in women, and an association between handgrip strength and type IIx fibers in men. The gluteus maximus showed no significant correlations with clinical parameters. CONCLUSION: This study identified complex associations between age, sex, handgrip strength, and muscle fiber composition in hip fracture patients, offering insights crucial for targeted interventions combating age-related muscle decline and improving musculoskeletal health.


Assuntos
Fraturas do Quadril , Músculo Quadríceps , Sarcopenia , Humanos , Masculino , Feminino , Idoso , Fraturas do Quadril/patologia , Sarcopenia/patologia , Músculo Quadríceps/patologia , Pessoa de Meia-Idade , Projetos Piloto , Idoso de 80 Anos ou mais , Força da Mão , Adulto , Densidade Óssea , Fibras Musculares Esqueléticas/patologia , Fibras Musculares Esqueléticas/metabolismo , Adulto Jovem , Envelhecimento/fisiologia , Envelhecimento/patologia , Fibras Musculares de Contração Rápida/patologia , Fibras Musculares de Contração Rápida/metabolismo
3.
Front Oncol ; 14: 1376831, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38774409

RESUMO

Background: Cancer metastasis is dependent on cell migration. Several mechanisms, including epithelial-to-mesenchymal transition (EMT) and actin fiber formation, could be involved in cancer cell migration. As a downstream effector of the Hippo signaling pathway, transcriptional coactivator with PDZ-binding motif (TAZ) is recognized as a key mediator of the metastatic ability of breast cancer cells. We aimed to examine whether TAZ affects the migration of breast cancer cells through the regulation of EMT or actin cytoskeleton. Methods: MCF-7 and MDA-MB-231 cells were treated with siRNA to attenuate TAZ abundance. Transwell migration assay and scratch wound healing assay were performed to study the effects of TAZ knockdown on cancer cell migration. Fluorescence microscopy was conducted to examine the vinculin and phalloidin. Semiquantitative immunoblotting and quantitative real-time PCR were performed to study the expression of small GTPases and kinases. Changes in the expression of genes associated with cell migration were examined through next-generation sequencing. Results: TAZ-siRNA treatment reduced TAZ abundance in MCF-7 and MDA-MB-231 breast cancer cells, which was associated with a significant decrease in cell migration. TAZ knockdown increased the expression of fibronectin, but it did not exhibit the typical pattern of EMT progression. TGF-ß treatment in MDA-MB-231 cells resulted in a reduction in TAZ and an increase in fibronectin levels. However, it paradoxically promoted cell migration, suggesting that EMT is unlikely to be involved in the decreased migration of breast cancer cells in response to TAZ suppression. RhoA, a small Rho GTPase protein, was significantly reduced in response to TAZ knockdown. This caused a decrease in the expression of the Rho-dependent downstream pathway, i.e., LIM kinase 1 (LIMK1), phosphorylated LIMK1/2, and phosphorylated cofilin, leading to actin depolymerization. Furthermore, myosin light chain kinase (MLCK) and phosphorylated MLC2 were significantly decreased in MDA-MB-231 cells with TAZ knockdown, inhibiting the assembly of stress fibers and focal adhesions. Conclusion: TAZ knockdown inhibits the migration of breast cancer cells by regulating the intracellular actin cytoskeletal organization. This is achieved, in part, by reducing the abundance of RhoA and Rho-dependent downstream kinase proteins, which results in actin depolymerization and the disassembly of stress fibers and focal adhesions.

4.
Am J Physiol Renal Physiol ; 326(1): F69-F85, 2024 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-37855039

RESUMO

Poly(ADP-ribosyl)ation (PARylation), as a posttranslational modification mediated by poly(ADP-ribose) polymerases (PARPs) catalyzing the transfer of ADP-ribose from NAD+ molecules to acceptor proteins, involves a number of cellular processes. As mice lacking the PARP-1 gene (Parp1) produce more urine, we investigated the role of PARP-1, the most prevalent member of the PARP family, in the vasopressin-responsive expression of aquaporin-2 (AQP2). In biotin-conjugated nicotinamide adenine dinucleotide (biotin-NAD+) pulldown and immunoprecipitation assays of poly(ADP)-ribose in mpkCCDc14 cells, immunoblots demonstrated that 1-deamino-8-D-arginine vasopressin (dDAVP) induced the PARylation of total proteins, associated with an increase in the cleavage of PARP-1 and cleaved caspase-3 expression. By inhibiting PARP-1 with siRNA, the abundance of dDAVP-induced AQP2 mRNA and protein was significantly diminished. In contrast, despite a substantial decrease in PARylation, the PARP-1 inhibitor (PJ34) had no effect on the dDAVP-induced regulation of AQP2 expression. The findings suggest that PARP-1 protein expression itself, and not PARP-1-mediated PARylation, is necessary for dDAVP-regulated AQP2 expression. Bioinformatic analysis revealed that 408 proteins interact with PARP-1 in the collecting duct (CD) cells of the kidney. Among them, the signaling pathway of the vasopressin V2 receptor was identified for 49 proteins. In particular, ß-catenin, which is phosphorylated at Ser552 by dDAVP, was identified as the PARP-1-interacting protein. A significant decrease of ß-catenin phosphorylation (Ser552) in response to dDAVP was associated with siRNA-mediated PARP-1 knockdown. Taken together, PARP-1 is likely to play a role in vasopressin-induced AQP2 expression by interacting with ß-catenin in renal CD cells.NEW & NOTEWORTHY The poly(ADP-ribose) polymerase (PARP) family catalyzes poly(ADP-ribosylation) (PARylation), which is one of the posttranslational modifications of largely undetermined physiological significance. This study investigated the role of PARP-1, the most prevalent member of the PARP family, in the vasopressin-responsive expression of aquaporin-2 (AQP2). The results demonstrated that PARP-1 protein expression itself, and not PARP-1-mediated PARylation, is necessary for dDAVP-regulated AQP2 expression. ß-Catenin, which is phosphorylated at Ser552 by dDAVP, was identified as the PARP-1-interacting protein.


Assuntos
Aquaporina 2 , Inibidores de Poli(ADP-Ribose) Polimerases , Animais , Camundongos , Aquaporina 2/genética , beta Catenina/metabolismo , Biotina/metabolismo , Desamino Arginina Vasopressina/farmacologia , Rim/metabolismo , NAD/metabolismo , Poli(ADP-Ribose) Polimerase-1/genética , Poli(ADP-Ribose) Polimerase-1/metabolismo , Poli Adenosina Difosfato Ribose/metabolismo , Poli(ADP-Ribose) Polimerases/genética , Poli(ADP-Ribose) Polimerases/metabolismo , RNA Interferente Pequeno , Vasopressinas/farmacologia , Vasopressinas/metabolismo
5.
Cell Death Dis ; 14(9): 618, 2023 09 21.
Artigo em Inglês | MEDLINE | ID: mdl-37735474

RESUMO

Immunosenescence and exhaustion are involved in the development and progression of type 2 diabetes (T2D) and metabolic liver diseases, including fatty liver, fibrosis, and cirrhosis, in humans. However, the relationships of the senescence and exhaustion of T cells with insulin resistance-associated liver diseases remain incompletely understood. To better define the relationship of T2D with nonalcoholic fatty liver disease, 59 patients (mean age 58.7 ± 11.0 years; 47.5% male) with T2D were studied. To characterize their systemic immunophenotypes, peripheral blood mononuclear cells were analyzed using flow cytometry. Magnetic resonance imaging (MRI)-based proton density fat fraction and MRI-based elastography were performed using an open-bore, vertical-field 3.0 T scanner to quantify liver fat and fibrosis, respectively. The participants with insulin resistance had a significantly larger population of CD28 - CD57+ senescent T cells among the CD4+ and CD8 + T cells than those with lower Homeostatic Model Assessment for Insulin Resistance (HOMA-IR) values. The abundances of senescent CD4+ and CD8 + T cells and the HOMA-IR positively correlated with the severity of liver fibrosis, assessed using MRI-based elastography. Interleukin 15 from hepatic monocytes was found to be an inducer of bystander activation of T cells, which is associated with progression of liver disease in the participants with T2D. Furthermore, high expression of genes related to senescence and exhaustion was identified in CD4+ and CD8 + T cells from the participants with nonalcoholic steatohepatitis or liver cirrhosis. Finally, we have also demonstrated that hepatic T-cell senescence and exhaustion are induced in a diet or chemical-induced mouse model with nonalcoholic steatohepatitis. In conclusion, we have shown that T-cell senescence is associated with insulin resistance and metabolic liver disease in patients with T2D.


Assuntos
Diabetes Mellitus Tipo 2 , Resistência à Insulina , Hepatopatia Gordurosa não Alcoólica , Humanos , Masculino , Animais , Camundongos , Pessoa de Meia-Idade , Idoso , Feminino , Diabetes Mellitus Tipo 2/complicações , Leucócitos Mononucleares , Exaustão das Células T , Cirrose Hepática , Modelos Animais de Doenças
6.
Int J Mol Sci ; 24(2)2023 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-36675199

RESUMO

mpkCCDc14 cells, a polarized epithelial cell line derived from mouse kidney cortical collecting ducts, are known to express the vasopressin V2 receptor (V2R) and aquaporin-2 (AQP2) that are responsive to vasopressin. However, a low abundance of the endogenous AQP2 protein in the absence of vasopressin and heterogeneity of AQP2 protein abundance among the cultured cells may limit the further application of the cell line in AQP2 studies. To overcome the limitation, we aimed to establish mpkCCDc14 cells constitutively expressing V2R and AQP2 via CRISPR/Cas9-mediated genome engineering technology (i.e., V2R-AQP2 cells). 3'- and 5'-Junction PCR revealed that the V2R-AQP2 expression cassette with a long insert size (~2.2 kb) was correctly integrated. Immunoblotting revealed the expression of products of integrated Aqp2 genes. Cell proliferation rate and dDAVP-induced cAMP production were not affected by the knock-in of Avpr2 and Aqp2 genes. The AQP2 protein abundance was significantly higher in V2R-AQP2 cells compared with control mpkCCDc14 cells in the absence of dDAVP and the integrated AQP2 was detected. Immunocytochemistry demonstrated that V2R-AQP2 cells exhibited more homogenous and prominent AQP2 labeling intensity in the absence of dDAVP stimulation. Moreover, prominent AQP2 immunolabeling (both AQP2 and pS256-AQP2) in the apical domain of the genome-edited cells was observed in response to dDAVP stimulation, similar to that in the unedited control mpkCCDc14 cells. Taken together, mpkCCDc14 cells constitutively expressing V2R and AQP2 via genome engineering could be exploited for AQP2 studies.


Assuntos
Aquaporina 2 , Túbulos Renais Coletores , Camundongos , Animais , Aquaporina 2/metabolismo , Desamino Arginina Vasopressina/metabolismo , Túbulos Renais Coletores/metabolismo , Vasopressinas/metabolismo , Membrana Celular/metabolismo
7.
Biochimie ; 188: 52-60, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33894294

RESUMO

Aquaporins (AQPs) are water channel proteins facilitating passive transport of water and other small molecules across biomembranes. Regulation of osmotic homeostasis via AQPs is accompanied by dynamic participation of various cellular signaling pathways. Recently emerging evidence reveals that functional roles of AQPs are further extended from the osmotic regulation via water permeation into the cell proliferation and differentiation. In particular, anomalous expression of AQPs has been demonstrated in various types of cancer cells and cancer stem-like cells and it has been proposed as markers for proliferation and progression of cancer cells. Thus, a more comprehensive view on AQPs could bring a great interest in the cell stemness accompanied by the expression of AQPs. AQPs are broadly expressed across tissues and cells in a cell type- and lineage-specific manner during development via spatiotemporal transcriptional regulation. Moreover, AQPs are expressed in various adult stem cells and cells associated with a stem cell niche as well as cancer stem-like cells. However, the expression and regulatory mechanisms of AQP expression in stem cells have not been well understood. This review highlighted the AQPs expression in stem cell niches/stem cells and the involvement of AQPs in the cell proliferation and signaling pathways associated with cell stemness.


Assuntos
Aquaporinas/fisiologia , Proliferação de Células , Transdução de Sinais , Células-Tronco/metabolismo , Animais , Biomarcadores , Diferenciação Celular , Humanos , Neoplasias/genética , Neoplasias/metabolismo , Neoplasias/patologia , Células-Tronco/citologia
8.
Kidney Int ; 99(1): 117-133, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32853632

RESUMO

Cell therapy using genome-engineered stem cells has emerged as a novel strategy for the treatment of kidney diseases. By exploiting genome editing technology, human umbilical cord-derived mesenchymal stem cells (hUC-MSCs) secreting an angiogenic factors or an anti-inflammatory factor were generated for therapeutic application in acute kidney injury. Junction polymerase chain reaction analysis verified zinc finger nucleases-assisted integration of the desired gene into the hUC-MSCs. Flow cytometry and differentiation assays indicated that genome editing did not affect the differentiation potential of these mesenchymal stem cells. Protein measurement in conditioned media with the use of ELISA and immunoblotting revealed the production and secretion of each integrated gene product. For cell therapy in the bilateral ischemia-reperfusion mouse model of acute kidney injury, our innovative scaffold-free cell sheets were established using a non-biodegradable temperature-responsive polymer. One of each type of scaffold-free cell sheets of either the angiogenic factor vascular endothelial grown factor or angiopoietin-1, or the anti-inflammatory factor erythropoietin, or α-melanocyte-stimulating hormone-secreting hUC-MSCs was applied to the decapsulated kidney surface. This resulted in significant amelioration of kidney dysfunction in the mice with acute kidney injury, effects that were superior to intravenous administration of the same genome-engineered hUC-MSCs. Thus, our scaffold-free cell sheets of genome-engineered mesenchymal stem cells provides therapeutic effects by inhibiting acute kidney injury via angiogenesis or anti-inflammation.


Assuntos
Injúria Renal Aguda , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais , Injúria Renal Aguda/genética , Injúria Renal Aguda/terapia , Animais , Diferenciação Celular , Camundongos , Cordão Umbilical
9.
Cells ; 9(5)2020 05 13.
Artigo em Inglês | MEDLINE | ID: mdl-32413996

RESUMO

Sorting nexin 27 (SNX27), a PDZ (Postsynaptic density-95/Discs large/Zonula occludens 1) domain-containing protein, cooperates with a retromer complex, which regulates intracellular trafficking and the abundance of membrane proteins. Since the carboxyl terminus of aquaporin-2 (AQP2c) has a class I PDZ-interacting motif (X-T/S-X-Φ), the role of SNX27 in the regulation of AQP2 was studied. Co-immunoprecipitation assay of the rat kidney demonstrated an interaction of SNX27 with AQP2. Glutathione S-transferase (GST) pull-down assays revealed an interaction of the PDZ domain of SNX27 with AQP2c. Immunocytochemistry of HeLa cells co-transfected with FLAG-SNX27 and hemagglutinin (HA)-AQP2 also revealed co-localization throughout the cytoplasm. When the PDZ domain was deleted, punctate HA-AQP2 labeling was localized in the perinuclear region. The labeling was intensively overlaid by Lysotracker staining but not by GM130 labeling, a cis-Golgi marker. In rat kidneys and primary cultured inner medullary collecting duct cells, the subcellular redistribution of SNX27 was similar to AQP2 under 1-deamino-8-D-arginine vasopressin (dDAVP) stimulation/withdrawal. Cell surface biotinylation assay showed that dDAVP-induced AQP2 translocation to the apical plasma membrane was unaffected after SNX27 knockdown in mpkCCD cells. In contrast, the dDAVP-induced AQP2 protein abundance was significantly attenuated without changes in AQP2 mRNA expression. Moreover, the AQP2 protein abundance was markedly declined during the dDAVP withdrawal period after stimulation under SNX27 knockdown, which was inhibited by lysosome inhibitors. Autophagy was induced after SNX27 knockdown in mpkCCD cells. Lithium-induced nephrogenic diabetes insipidus in rats revealed a significant downregulation of SNX27 in the kidney inner medulla. Taken together, the PDZ domain-containing SNX27 interacts with AQP2 and depletion of SNX27 contributes to the autophagy-lysosomal degradation of AQP2.


Assuntos
Aquaporina 2/metabolismo , Túbulos Renais Coletores/metabolismo , Lisossomos/metabolismo , Proteólise , Nexinas de Classificação/metabolismo , Animais , Aquaporina 2/genética , Autofagia , Diabetes Insípido/metabolismo , Diabetes Insípido/patologia , Células HEK293 , Células HeLa , Humanos , Lítio , Masculino , Ligação Proteica , RNA Interferente Pequeno/metabolismo , Ratos Sprague-Dawley , Nexinas de Classificação/genética
10.
FASEB J ; 34(2): 3379-3398, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31922312

RESUMO

Aquaporin-5 (AQP5) plays a role in breast cancer cell migration. This study aimed to identify AQP5-targeting miRNAs and examine their effects on breast cancer cell migration through exosome-mediated delivery. Bioinformatic analyses identified miR-1226-3p, miR-19a-3p, and miR-19b-3p as putative regulators of AQP5 mRNA. Immunoblotting revealed a decrease of AQP5 protein abundance when each of these miRNAs was transfected into human breast cancer MDA-MB-231 cells. Quantitative real-time PCR demonstrated the reduction of AQP5 mRNA expression by the transfection of miR-1226-3p and a luciferase reporter assay revealed the reduction of AQP5 translation after the transfection of miR-19b-3p in MDA-MB-231 cells. Consistently, the transfection of each miRNA impeded cell migration. Pathway enrichment analyses showed that these three miRNAs regulate target genes, which were predominantly enriched in the gap junction pathway. For the efficient delivery of AQP5-targeting miRNAs to breast cancer cells, exosomes expressing both miRNAs and a peptide targeting interleukin-4 receptor, which is highly expressed in breast cancer cells, were bioengineered and their inhibitory effects on AQP5 protein expression and cell migration were demonstrated in MDA-MB-231 cells. Taken together, AQP5-regulating miRNAs are identified, which could be exploited for the inhibition of breast cancer cell migration via the exosome-mediated delivery.


Assuntos
Neoplasias da Mama/metabolismo , Movimento Celular , Exossomos/metabolismo , MicroRNAs/metabolismo , Aquaporina 5/genética , Aquaporina 5/metabolismo , Feminino , Células HEK293 , Humanos , Subunidade alfa de Receptor de Interleucina-4/metabolismo , Células MCF-7 , MicroRNAs/genética , Oligopeptídeos/metabolismo
11.
Exp Eye Res ; 121: 58-65, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24534570

RESUMO

Signature ophthalmic characteristics of Wilson's disease (WD) are regarded as diagnostically important manifestations of the disease. Previous studies have proved the common occurrence of copper accumulation in the liver of patients with WD. However, in the case of sunflower cataracts, one of the rare diagnostic signs of WD, no study has demonstrated copper accumulation in the lens capsules of sunflower cataracts in WD patients. To investigate the nanostructure and elemental composition of sunflower cataracts in WD, transmission electron microscopy (TEM) was done on the capsulorhexised anterior lens capsule of sunflower cataracts in WD in order to evaluate anatomical variation and elemental changes. We utilized energy dispersive X-ray spectroscopy (EDS) to investigate the elemental composition of the lens capsule using both point and mapping spectroscopy. Quantitative analysis was performed for relative comparison of the elements. TEM showed the presence of granular deposits of varying size (20-350 nm), appearing mainly in the posterior one third of the anterior capsule. The deposits appeared in linear patterns with scattered dots. There were no electron-dense particles in the epithelial cell layer of the lens. Copper and sulfur peaks were consistently revealed in electron-dense granular deposits. In contrast, copper and sulfur peaks were absent in other tissues, including granule-free lens capsules and epithelial tissue. Most copper was exclusively located in clusters of electron-dense particles, and the copper distribution overlapped with sulfur on mapping spectroscopy. Quantitative analysis presented inconsistent ratios of copper to sulfur in each electron-dense granule. The mean ratio of copper to sulfur was about 3.25 (with a range of 2.39-3.78). This is the first elemental analysis of single electron particles in sunflower cataracts using EDS in the ophthalmic area. Sunflower cataracts with WD are assumed to be the result of accumulation of heterogeneous compounds composed of several materials, including copper, sulfur, and/or copper-binding proteins. Linear patterns of copper and sulfur deposition were detected in various sizes and composition ratios with these elements in cases of WD.


Assuntos
Cápsula Anterior do Cristalino/metabolismo , Proteínas de Transporte/metabolismo , Catarata/metabolismo , Degeneração Hepatolenticular/metabolismo , Microscopia Eletrônica de Transmissão e Varredura , Espectrometria por Raios X , Compostos de Enxofre/metabolismo , Adulto , Cápsula Anterior do Cristalino/ultraestrutura , Catarata/diagnóstico , Degeneração Hepatolenticular/diagnóstico , Humanos , Imageamento por Ressonância Magnética , Masculino , Facoemulsificação
12.
BMC Ophthalmol ; 13: 67, 2013 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-24188326

RESUMO

BACKGROUND: The purpose of this study was to evaluate the relationship between patterns of localized retinal nerve fiber layer (RNFL) defects and the degree of myopia in patients with normal-tension glaucoma (NTG). METHODS: We retrospectively reviewed medical records of patients with high myopia (42 eyes; spherical equivalent [SE] < -6.0 diopters [D]), low to moderate myopia (93 eyes; SE -6.0D ~ and -0.5D), and emmetropia (65 eyes; SE -0.5D ~ +0.5D), all of which were diagnosed as having NTG with localized RNFL defects. On RNFL photographs, the proximity of the RNFL defect to the center of the fovea (angle I) and the sum of the angular width of the defects (angle II) were determined. The patterns of localized RNFL defects were then compared with respect to differences in angles I and II. RESULTS: Angle I was significantly smaller in the high myopia group than in the low to moderate myopia group (p = 0.028) and the emmetropia group (p = 0.044), while angle II was significantly larger in the high myopia group compared with the low to moderate myopia group and the emmetropia group (p < 0.001, p = 0.007). CONCLUSIONS: Among subjects with NTG, localized RNFL defects are wider and closer to the fovea in eyes with high myopia than those with low to moderate myopia or emmetropia.


Assuntos
Glaucoma de Baixa Tensão/patologia , Miopia/patologia , Fibras Nervosas/patologia , Retina/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos Transversais , Progressão da Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Análise de Regressão , Estudos Retrospectivos , Adulto Jovem
13.
Korean J Ophthalmol ; 26(2): 104-10, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22511836

RESUMO

PURPOSE: To evaluate the effects of various factors on the variability of retinal nerve fiber layer (RNFL) thickness measurements using the Stratus optical coherence tomography (OCT) in normal and glaucomatous eyes. METHODS: Four hundred seventy-four subjects (103 normal eyes and 371 glaucomatous eyes) were scanned to determine the RNFL thickness measurements using the Stratus OCT. Measurements were obtained twice during the same day. The standard deviation (SD) was used to compare the variability in RNFL thickness measurements of the normal subjects to that of the glaucomatous patients. Multivariate regression analysis was used to evaluate which covariates were independent predictors of SD in overall mean RNFL thickness. RESULTS: The mean SD of all RNFL thickness measurements was larger in the glaucoma group except in one sector. In the multivariate regression analysis, the average signal strength (SS) and the relative SS change (difference in SS between initial and repeat scans, divided by initial SS) were independent predictors of the SD in the RNFL thickness measurements (partial R(2) = 0.018, 0.013; p = 0.016, 0.040, respectively). CONCLUSIONS: Glaucomatous eyes tend to be more variable than normal eyes in RNFL thickness measurement using the Straus OCT. The average SS and the relative SS changes appear to correlate with the variability in RNFL thickness measurement. Therefore, the results of the RNFL analysis should not be interpreted independently of these factors.


Assuntos
Glaucoma/patologia , Fibras Nervosas/patologia , Retina/citologia , Retina/patologia , Tomografia de Coerência Óptica/métodos , Tomografia de Coerência Óptica/normas , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Valor Preditivo dos Testes , Valores de Referência , Análise de Regressão , Reprodutibilidade dos Testes
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