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BACKGROUND: Macular neovascularization (MNV) has been evaluated by optical coherence tomography (OCT) imaging using various approaches. However, few studies have examined their differences. This study analyzed type 1 MNV with a combination of two approaches: scale bar and binarization. METHODS: We enrolled 84 patients with untreated type 1 MNV. We measured choroidal parameters using a scale bar and defined the ratios of superficial choroidal thickness to choroidal vessel diameter (SV ratios). We also used binarization and calculated the ratios of the luminal to the choroidal area (LC ratios) in two directions (horizontal and vertical). RESULTS: Fifty-one patients (61%) were classified as having polyps. SV ratios in the group with polyps were significantly lower than in the group without (p < 0.001). The receiver operating characteristic (ROC) curve showed that the SV ratio was predictive of polyps (AUC 0.733, 95% CI: 0.621-0.844). In patients without polyps, horizontal LC ratios were significantly higher in a subgroup with subretinal fluid than in those without (p = 0.047). The ROC curve showed that the LC ratio was predictive of subretinal fluid (AUC 0.722, 95% CI: 0.517-0.926). CONCLUSION: The SV ratio reflects the MNV disease type, whereas the LC ratio reflects MNV disease activity. Establishing cut-off values for each ratio may be useful for MNV diagnosis.
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BACKGROUND: The effect of laparoscopic surgery on short-term outcomes in colorectal cancer patients over 90 years old has remained unclear. METHODS: We reviewed 87 colorectal cancer patients aged over 90 years who underwent surgery between 2016 and 2022. Patients were divided into an open surgery group (n = 22) and a laparoscopic surgery group (n = 65). The aim of this study was to investigate the effect of laparoscopic surgery on postoperative outcome in elderly colorectal cancer patients, as compared to open surgery. RESULTS: Seventy-eight patients (89.7%) had comorbidities. Frequency of advanced T stage was lower with laparoscopic surgery (p = 0.021). Operation time was longer (open surgery 146 min vs. laparoscopic surgery 203 min; p = 0.002) and blood loss was less (105 mL vs. 20 mL, respectively; p < 0.001) with laparoscopic surgery. Length of hospitalization was longer with open surgery (22 days vs. 18 days, respectively; p = 0.007). Frequency of infectious complications was lower with laparoscopic surgery (18.5%) than with open surgery (45.5%; p = 0.021). Multivariate analysis revealed open surgery (p = 0.026; odds ratio, 3.535; 95% confidence interval, 1.159-10.781) as an independent predictor of postoperative infectious complications. CONCLUSIONS: Laparoscopic colorectal resection for patients over 90 years old is a useful procedure that reduces postoperative infectious complications.
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Neoplasias Colorretais , Laparoscopia , Idoso de 80 Anos ou mais , Humanos , Colectomia/efeitos adversos , Colectomia/métodos , Neoplasias Colorretais/cirurgia , Japão/epidemiologia , Laparoscopia/efeitos adversos , Laparoscopia/métodos , Complicações Pós-Operatórias/epidemiologia , Estudos Retrospectivos , Resultado do TratamentoRESUMO
Retinal vein occlusion (RVO) is a major retinal disease caused by venous thrombosis. Although several studies have proposed an association between venous thrombosis and von Willebrand factor (VWF), the association between RVO and VWF remains unclear. We aimed to investigate the association between RVO and VWF and the alteration of VWF levels under anti-vascular endothelial growth factor (VEGF) treatment. We enrolled 55 patients with RVO involved cystoid macular edema. They received intravitreal injection of anti-VEGF drugs, either ranibizumab or aflibercept. We examined the clinical data and measured plasma VWF antigen and a disintegrin and metalloproteinase with a thrombospondin type 1 motif, member 13 (ADAMTS13) activity to identify variabilities during treatment. At baseline, there was no significant difference between the RVO group and age-matched controls in both VWF antigen and ADAMTS13 activity levels, but ADAMTS13 activity was significantly lower in central RVO than in branch RVO (P = 0.015). In branch RVO, VWF antigen was negatively correlated with central choroidal thickness (r = -0.51, P < 0.001). In branch RVO after anti-VEGF treatment, VWF antigen levels decreased significantly from 134% at baseline to 109% at 1 day (P = 0.002) and 107% at 1 month (P = 0.030) after treatment. In contrast, ADAMTS13 activity showed no significant difference during this period. In branch RVO at 1 month after treatment, VWF antigen was negatively correlated with central choroidal thickness (r = -0.47, P = 0.001). Our findings suggest an association between VWF and central choroidal thickness in patients with branch RVO, thus the measurement of VWF may be useful for evaluating disease activity and prognosis.
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Edema Macular , Oclusão da Veia Retiniana , Inibidores da Angiogênese/uso terapêutico , Desintegrinas , Fatores de Crescimento Endotelial/uso terapêutico , Humanos , Injeções Intravítreas , Edema Macular/etiologia , Ranibizumab/uso terapêutico , Oclusão da Veia Retiniana/complicações , Oclusão da Veia Retiniana/tratamento farmacológico , Oclusão da Veia Retiniana/metabolismo , Trombospondinas , Tomografia de Coerência Óptica/efeitos adversos , Fator A de Crescimento do Endotélio Vascular/uso terapêutico , Acuidade Visual , Fator de von WillebrandRESUMO
BACKGROUND: Hemodialysis patients who undergo surgery have a high risk of postoperative complications. The aim of this study was to determine whether colon cancer surgery can be safely performed in hemodialysis patients. METHODS: This multicenter retrospective study included 1372 patients who underwent elective curative resection surgery for colon cancer between April 2016 and March 2020. RESULTS: Of the total patients, 19 (1.4%) underwent hemodialysis, of whom 19 (100%) had poor performance status and 18 had comorbidities (94.7%). Minimally invasive surgery was performed in 78.9% of hemodialysis patients. The postoperative complication rate was significantly higher in hemodialysis than non-hemodialysis patients (36.8% vs. 15.5%, p = 0.009). All postoperative complications in the hemodialysis patients were infectious type. Multivariate analysis revealed a significant association of hemodialysis with complications (odds ratio, 2.9362; 95%CI, 1.1384-7.5730; p = 0.026). CONCLUSION: Despite recent advances in perioperative management and minimally invasive surgery, it is necessary to be aware that short-term complications can still occur, especially infectious complications in hemodialysis patients.
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Neoplasias do Colo/cirurgia , Procedimentos Cirúrgicos do Sistema Digestório/mortalidade , Procedimentos Cirúrgicos Eletivos/mortalidade , Complicações Pós-Operatórias/mortalidade , Diálise Renal/estatística & dados numéricos , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias do Colo/patologia , Feminino , Seguimentos , Humanos , Japão/epidemiologia , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/epidemiologia , Prognóstico , Estudos Retrospectivos , Fatores de Risco , Taxa de Sobrevida , Adulto JovemRESUMO
Pachychoroid neovasculopathy (PNV) is a new concept of macular disorder. Some cases diagnosed as age-related macular degeneration (AMD) have been re-diagnosed as PNV. However, the biological features of PNV are still uncertain. The purpose of this study was to compare PNV and AMD by analyses focusing on von Willebrand factor (VWF) and complement factor H (CFH). Ninety-seven patients who were previously diagnosed with treatment naïve AMD were enrolled in this study. They were re-classified as either PNV or AMD based on the clinical criteria and 33 patients were classified as PNV and 64 patients as AMD. We examined the clinical data, analyzed VWF multimer and two genetic polymorphisms (I62V and Y402H) in the CFH. PNV group was significantly younger than AMD group (P = 0.001). In both I62V and Y402H, there were no significant differences between PNV and AMD while the recessive homozygous (AA) was found only in PNV group in I62V. The presence of unusually large VWF multimers (UL-VWFMs) and subretinal hemorrhages were significantly higher in PNV than in AMD (P = 0.045, P = 0.020, respectively). Thus, the residual UL-VWFMs may result in platelet thrombosis and hemorrhages in the choriocapillaris of PNV. In conclusion, our results suggest the biological differences between PNV and AMD.
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Neovascularização de Coroide/genética , Degeneração Macular/genética , Fator de von Willebrand/análise , Idoso , Idoso de 80 Anos ou mais , Neovascularização de Coroide/sangue , Neovascularização de Coroide/patologia , Fator H do Complemento/análise , Fator H do Complemento/genética , Estudos Transversais , Feminino , Humanos , Japão , Degeneração Macular/sangue , Degeneração Macular/patologia , Masculino , Polimorfismo Genético , Hemorragia Retiniana , Fator de von Willebrand/genéticaRESUMO
AMPA receptors are responsible for fast excitatory synaptic transmission in the mammalian brain. Post-translational protein S-palmitoylation of AMPA receptor subunits GluA1-4 reversibly regulates synaptic AMPA receptor expression, resulting in long-lasting changes in excitatory synaptic strengths. Our previous studies have shown that GluA1 C-terminal palmitoylation-deficient (GluA1C811S) mice exhibited hyperexcitability in the cerebrum and elevated seizure susceptibility without affecting brain structure or basal synaptic transmission. Moreover, some inhibitory GABAergic synapses-targeting anticonvulsants, such as valproic acid, phenobarbital, and diazepam, had less effect on these AMPA receptor palmitoylation-deficient mutant mice. This work explores pharmacological effect of voltage-gated ion channel-targeted anticonvulsants, phenytoin and trimethadione, on GluA1C811S mice. Similar to GABAergic synapses-targeting anticonvulsants, anticonvulsive effects were also reduced for both sodium channel- and calcium channel-blocking anticonvulsants, which suppress excess excitation. These data strongly suggest that the GluA1C811S mice generally underlie the excessive excitability in response to seizure-inducing stimulation. AMPA receptor palmitoylation site could be a novel target to develop unprecedented type of anticonvulsants and GluA1C811S mice are suitable as a model animal for broadly evaluating pharmacological effectiveness of antiepileptic drugs.
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During development, neural progenitors are in proliferative and immature states; however, the molecular machinery that cooperatively controls both states remains elusive. Here, we report that cyclin D1 (CCND1) directly regulates both proliferative and immature states of cerebellar granule cell progenitors (GCPs). CCND1 not only accelerates cell cycle but also upregulates ATOH1 protein, an essential transcription factor that maintains GCPs in an immature state. In cooperation with CDK4, CCND1 directly phosphorylates S309 of ATOH1, which inhibits additional phosphorylation at S328 and consequently prevents S328 phosphorylation-dependent ATOH1 degradation. Additionally, PROX1 downregulates Ccnd1 expression by histone deacetylation of Ccnd1 promoter in GCPs, leading to cell cycle exit and differentiation. Moreover, WNT signaling upregulates PROX1 expression in GCPs. These findings suggest that WNT-PROX1-CCND1-ATOH1 signaling cascade cooperatively controls proliferative and immature states of GCPs. We revealed that the expression and phosphorylation levels of these molecules dynamically change during cerebellar development, which are suggested to determine appropriate differentiation rates from GCPs to GCs at distinct developmental stages. This study contributes to understanding the regulatory mechanism of GCPs as well as neural progenitors.
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Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Cerebelo/crescimento & desenvolvimento , Cerebelo/metabolismo , Ciclina D1/metabolismo , Grânulos Citoplasmáticos/metabolismo , Fosforilação/fisiologia , Células-Tronco/metabolismo , Animais , Ciclo Celular/genética , Diferenciação Celular/fisiologia , Divisão Celular/fisiologia , Proliferação de Células/fisiologia , Células Cultivadas , Proteínas Hedgehog/metabolismo , Camundongos , Neurogênese/fisiologia , Transdução de Sinais/fisiologia , Fatores de TranscriçãoRESUMO
Cerebellar granule cells (GCs) are cells which comprise over 50% of the neurons in the entire nervous system. GCs enable the cerebellum to properly regulate motor coordination, learning, and consolidation, in addition to cognition, emotion and language. During GC development, maternal GC progenitors (GCPs) divide to produce not only postmitotic GCs but also sister GCPs. However, the molecular machinery for regulating the proportional production of distinct sister cell types from seemingly uniform GCPs is not yet fully understood. Here we report that Notch signaling creates a distinction between GCPs and leads to their proportional differentiation in mice. Among Notch-related molecules, Notch1, Notch2, Jag1, and Hes1 are prominently expressed in GCPs. In vivo monitoring of Hes1-promoter activities showed the presence of two types of GCPs, Notch-signaling ON and OFF, in the external granule layer (EGL). Single-cell RNA sequencing (scRNA-seq) and in silico analyses indicate that ON-GCPs have more proliferative and immature properties, while OFF-GCPs have opposite characteristics. Overexpression as well as knock-down (KD) experiments using in vivo electroporation showed that NOTCH2 and HES1 are involved cell-autonomously to suppress GCP differentiation by inhibiting NEUROD1 expression. In contrast, JAG1-expressing cells non-autonomously upregulated Notch signaling activities via NOTCH2-HES1 in surrounding GCPs, eventually suppressing their differentiation. These findings suggest that Notch signaling results in the proportional generation of two types of cells, immature and differentiating GCPs, which contributes to the well-organized differentiation of GCs.
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Cerebelo , Transdução de Sinais , Animais , Diferenciação Celular , Grânulos Citoplasmáticos , Camundongos , Células-TroncoRESUMO
INTRODUCTION: The impact of obesity on short-term outcomes after laparoscopic colorectal surgery (LAC) in Asian patients is unclear. The purpose of the present multicenter study was to evaluate the safety and feasibility of LAC in obese Japanese patients. METHODS: We retrospectively reviewed 1705 patients who underwent LAC between April 2016 and February 2019. Patients were classified according to body mass index (BMI): non-obese (BMI < 25 kg/m2 , n = 1335), obese I (BMI 25-29.9 kg/m2 , n = 313), and obese II (BMI ≥30 kg/m2 , n = 57). Clinical characteristics and surgical outcomes were compared among the three groups. RESULTS: The proportion of patients with comorbidities (non-obese, 58.1%; obese I, 69.6%; obese II, 75.4%; P < .001) and median operation time (non-obese, 224 minutes; obese I, 235 minutes; obese II, 258 minutes; P = .004) increased significantly as BMI increased. The conversion rate was similar among the groups (P = .715). Infectious complications were significantly high in obese II patients (non-obese, 10.4%; obese I, 8.3%; obese II, 28.1%; P < .001). Multivariate analysis revealed that in obese II patients, BMI was an independent predictive factor of infectious postoperative complications (odds ratio 2.648; 95% confidence interval, 1.421-4.934; P = .002). CONCLUSION: LAC has an increased risk of postoperative infectious complications in obese II patients, despite improvements in surgical technique. Management of obese II colorectal cancer patients requires meticulous perioperative management.
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Neoplasias Colorretais , Laparoscopia , Obesidade/complicações , Adulto , Idoso , Idoso de 80 Anos ou mais , Índice de Massa Corporal , Colectomia , Neoplasias Colorretais/complicações , Neoplasias Colorretais/cirurgia , Feminino , Humanos , Japão , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Resultado do Tratamento , Adulto JovemRESUMO
PURPOSE: We investigated 10-year changes in baseline best-corrected visual acuity (BCVA), as well as functional and anatomical changes at 1 and 2 years after initial treatment, in eyes with treatment-naïve neovascular age-related macular degeneration (nAMD). METHODS: This retrospective, multicenter, case series reviewed patients with treatment-naïve nAMD who underwent initial treatment from 2006 to 2015, using photodynamic therapy (PDT), anti-vascular endothelial growth factor (VEGF), or a combination of PDT and anti-VEGF. BCVA and central retinal subfield thickness (CRST), were measured at baseline and at 1 or 2 years of follow-up. RESULTS: In total, 3096 eyes of 3096 patients were included from 14 hospitals. Mean BCVA at baseline became significantly better over the 10-year study period (P < 0.001). BCVA at 1 year significantly improved from baseline in patients who underwent initial treatment from 2009 to 2015 (P = 0.001, 2009; P = 0.004, 2010; P = 0.01, 2011; P < 0.001, 2012-2015). BCVA at 2 years significantly improved from baseline in patients who underwent initial treatment from 2012 to 2015 (P < 0.001, 2012; P < 0.001, 2013-2015). CRST at 1 year decreased significantly from CRST at baseline, each year from 2006 to 2015 (P < 0.001, 2006-2015). CRST at 2 years decreased significantly from CRST at baseline, each year from 2006 to 2015 (P = 0.03, 2006; P < 0.001, 2007-2015). CONCLUSION: Baseline BCVA with treatment-naïve nAMD tended to become better during the study period. BCVA at 1 year improved in the era of anti-VEGF; BCVA at 2 years improved in patients who underwent initial treatment in 2012 or later; and CRST decreased in each year during the study period.
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Inibidores da Angiogênese , Degeneração Macular , Inibidores da Angiogênese/uso terapêutico , Humanos , Injeções Intravítreas , Japão/epidemiologia , Degeneração Macular/diagnóstico , Degeneração Macular/tratamento farmacológico , Ranibizumab , Estudos Retrospectivos , Tomografia de Coerência Óptica , Resultado do Tratamento , Fator A de Crescimento do Endotélio Vascular , Acuidade VisualRESUMO
A proper balance between proliferation and differentiation of cerebellar granule cell precursors (GCPs) is required for appropriate cerebellar morphogenesis. The Skp1-Cullin1-F-box (SCF) complex, an E3 ubiquitin ligase complex, is involved in polyubiquitination and subsequent degradation of various cell cycle regulators and transcription factors. However, it remains unknown how the SCF complex affects proliferation and differentiation of GCPs. In this study, we found that the scaffold protein Cullin1, and F-box proteins Skp2, ß-TrCP1 and ß-TrCP2 are expressed in the external granule layer (EGL). Knockdown of these molecules in the EGL showed that Cullin1, Skp2 and ß-TrCP2 enhanced differentiation of GCPs. We also observed accumulation of cyclin-dependent kinase inhibitor p27 in GCPs when treated with a Cullin1 inhibitor or proteasome inhibitor. Furthermore, knockdown of p27 rescued enhancement of differentiation by Cullin1 knockdown. These results suggest that the SCF complex is involved in the maintenance of the proliferative state of GCPs through p27 degradation. In addition, inhibition of Cullin1 activity also prevented cell proliferation and enhanced accumulation of p27 in Daoy cells, a cell line derived from the sonic hedgehog subtype of medulloblastoma. This suggested that excess degradation of p27 through the SCF complex causes overproliferation of medulloblastoma cells.
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Cerebelo/citologia , Células-Tronco Neurais/metabolismo , Neurogênese , Proteínas Quinases Associadas a Fase S/metabolismo , Proteínas Contendo Repetições de beta-Transducina/metabolismo , Animais , Linhagem Celular Tumoral , Proliferação de Células , Células Cultivadas , Cerebelo/metabolismo , Proteínas Culina/metabolismo , Inibidor de Quinase Dependente de Ciclina p27/metabolismo , Células HEK293 , Humanos , Camundongos , Camundongos Endogâmicos ICR , Células-Tronco Neurais/citologia , Proteínas Quinases Associadas a Fase S/genética , UbiquitinaçãoRESUMO
BACKGROUND: Polypoidal choroidal vasculopathy (PCV) is one of the disorders within the pachychoroid spectrum diseases. The presence of pachyvessels is one of the characteristics of pachychoroid disorders. However, the relationship between the presence of pachyvessels and the clinical characteristics of PCV eyes has not been determined. The purpose of this study was to determine the relationship between the presence of choroidal pachyvessels and the clinical characteristics of eyes with PCV. METHODS: The medical records of patients who were diagnosed with PCV and were treatment-naïve were reviewed. Fluorescein and indocyanine green angiography, fundus photography, spectral domain optical coherence tomography (SD-OCT), and enhanced depth imaging OCT (EDI-OCT) were used to obtain images of the choroid. The presence of pathologically dilated outer choroidal vessels, pachyvessels, was determined by ICGA images. These pachyvessels were confirmed to correspond with the large choroidal vessels in the EDI OCT images. The PCV eyes were divided into two groups based on the presence or absence of pachyvessels and clinical features and subfoveal choroidal thickness (SFCT) were evaluated between the two groups. RESULTS: Eighty-six eyes of 84 patients with PCV were evaluated. Pachyvessels were detected in 48 eyes (55.8%). The mean SFCT was 203.9 ± 83.9 µm in all 86 eyes, and it was significantly thinner in eyes with pachyvessels (+) than without pachyvessels (-) (183.2 ± 58.4 µm vs 230.2 ± 103.1 µm; P = 0.01). The differences in the incidence of subretinal fluid, pigment epithelial detachments, and hemorrhages between the two groups were not significant. However, the PCV eyes in pachyvessels (+) group with hemorrhage had the thinnest choroid (P = 0.047). The choroidal features of the fellow eyes were similar to those of the PCV affected eyes, that is, the fellow eyes in pachyvessels (+) group had pachyvessels and the fellow eyes in pachyvessels (-) group did not have pachyvessels. CONCLUSIONS: Pachyvessels were presented 55.8% in eyes with PCV, and these eyes had the thin SFCT. The presence of pachyvessels and attenuation of the inner choroid were probably due to the pathological changes in the eyes with PCV.
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Corioide/irrigação sanguínea , Neovascularização de Coroide/diagnóstico , Pólipos/diagnóstico , Idoso , Idoso de 80 Anos ou mais , Neovascularização de Coroide/fisiopatologia , Corantes/administração & dosagem , Feminino , Angiofluoresceinografia , Humanos , Verde de Indocianina/administração & dosagem , Masculino , Pessoa de Meia-Idade , Pólipos/fisiopatologia , Estudos Retrospectivos , Tomografia de Coerência Óptica , Acuidade VisualRESUMO
Cerebellar granule cell precursors (GCPs) and granule cells (GCs) constitute a good model system to investigate proliferation of neural precursors and differentiation of neurons. During development, GCPs proliferate in the outer external granule cell layer (outer EGL) and then exit the cell cycle in the inner EGL to become GCs, which inwardly migrate to the inner granule cell layer (IGL). Misregulation of GCP proliferation or GC differentiation leads to maldevelopment of the cerebellum and the formation of a cerebellar tumor, medulloblastoma. Despite many efforts in this field, the mechanisms underlying GC development remain elusive. In this study, we performed detailed immunostaining in the developing cerebellum, with particular focus on GCPs and GCs, looking at several transcription factors, signaling molecules, cell cycle regulators, some of which are known to regulate neural development. Interestingly, we found distinct distribution patterns of certain proteins within the outer and inner EGL, suggesting the existence of subpopulations of GCPs and GCs in those layers. This study provides a basis for future studies on the cerebellar GC development and medulloblastoma.
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Cerebelo/metabolismo , Neurônios/metabolismo , Fatores de Transcrição/metabolismo , Animais , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Ciclo Celular , Diferenciação Celular/fisiologia , Divisão Celular , Proliferação de Células , Imuno-Histoquímica/métodos , Antígeno Ki-67/metabolismo , Meduloblastoma/metabolismo , Meduloblastoma/fisiopatologia , Camundongos , Camundongos Endogâmicos ICR , Neurogênese/fisiologia , Transdução de SinaisRESUMO
BACKGROUND: Amyloid beta (Aß) is a constituent of drusen that is a common sign of age-related macular degeneration (AMD). The purpose of this study was to investigate the effect of Aß on human retinal pigment epithelial (RPE) cells in culture. METHODS: Cells from a human RPE cell line (ARPE-19) were exposed to 0 to 25 µM of Aß 1-40 for 48 h, and the number of living cells was determined by WST-8 cleavage. Replicative DNA synthesis was measured by the incorporation of 5'-bromo-2'-deoxyuridine. The cell death pathway was investigated by the WST-8 cleavage assay after the addition of caspase-9 inhibitor, an anti-apoptotic factor. Real-time qRT-PCR was performed using Aß-exposed cellular RNA to determine the level of vascular endothelial growth factor (VEGF)-A and pigment epithelium derived factor (PEDF). To determine the effect of receptor-for-advanced glycation end products (RAGE), the siRNA for RAGE was inserted into ARPE-19 treated with Aß, and the levels of expression of VEGF-A and PEDF were determined. RESULTS: The number of living ARPE-19 cells was increased by exposure to 5 µM Aß but was decreased by exposure to 25 µM of Aß. Replicative DNA synthesis by ARPE-19 cells exposed to 25 µM of Aß was significantly decreased indicating that 25 µM of Aß inhibited cell proliferation. Real-time RT-PCR showed that the level of the mRNA of PEDF was increased by exposure to 5 µM Aß, and the levels of the mRNAs of PEDF and VEGF-A were also increased by exposure to 25 µM Aß. The addition of an inhibitor of caspase-9 blocked the decrease the number of ARPE-19 cells exposed to 25 µM Aß. Exposure to si-RAGE attenuated the increase of VEGF-A and PEDF mRNA expression in ARPE-19 exposed to Aß. CONCLUSIONS: Exposure of ARPE-19 cells to low concentrations of Aß increases the level of PEDF which then inhibits the apoptosis of ARPE-19 cells leading to RPE cell proliferation. Exposure to high concentrations of Aß induces RPE cell death and enhances the expression of the mRNA of VEGF-A in RPE cells. The Aß-RAGE pathway may lead to the expression VEGF-A and PEDF in RPE cells. These results suggest that Aß is strongly related to the pathogenesis of choroidal neovascularization.
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Peptídeos beta-Amiloides/farmacologia , Células Epiteliais/efeitos dos fármacos , Epitélio Pigmentado da Retina/citologia , Morte Celular/efeitos dos fármacos , Células Cultivadas , Relação Dose-Resposta a Droga , Células Epiteliais/metabolismo , Proteínas do Olho/metabolismo , Humanos , Fatores de Crescimento Neural/metabolismo , Receptor para Produtos Finais de Glicação Avançada/metabolismo , Serpinas/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismoRESUMO
BACKGROUND: AMPA receptors predominantly mediate fast excitatory synaptic transmission in the mammalian brain. Post-translational protein S-palmitoylation of AMPA receptor GluA subunits at their C-termini reversibly controls the receptors trafficking to and from excitatory glutamatergic synapses. Excitatory inputs to neurons induce the expression of immediate early genes (IEGs), including Arc, with particular spatial patterns. In the hippocampal dentate gyrus, Arc is mainly expressed in the upper (dorsal) blade at the basal state. GluA1 C-terminal palmitoylation-deficient (GluA1C811S) mice showed enhanced seizure susceptibility and disturbed synaptic plasticity without impaired gross anatomy or basal synaptic transmission. These mutant mice also exhibited an increased expression of IEG products, c-Fos and Arc proteins, in the hippocampus and cerebral cortex. In this report, we further analyzed excitability and Arc expression pattern in the dentate gyrus of GluA1C811S mice. METHODS AND RESULTS: Electrophysiological analysis of granule neurons to measure the evoked excitatory postsynaptic current/evoked inhibitory postsynaptic current ratio revealed that excitatory/inhibitory (E/I) balance was normal in GluA1C811S mice. In contrast, immunohistochemical staining showed an abnormal distribution of Arc-positive cells between upper and lower (ventral) blades of the dentate gyrus in these mutant mice. These data suggest that deficiency of GluA1 palmitoylation causes perturbed neuronal inputs from the entorhinal cortex to the dentate gyrus, which potentially underlies the excessive excitability in response to seizure-inducing stimulation. CONCLUSION: Our findings conclude that an appropriate regulation of Arc expression in the dentate gyrus, ensured by AMPA receptor palmitoylation, may be critical for stabilizing hippocampal neural circuits and may suppress excess excitation.
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Proteínas do Citoesqueleto/genética , Giro Denteado/metabolismo , Genes Precoces , Mutação de Sentido Incorreto , Proteínas do Tecido Nervoso/genética , Receptores de AMPA/metabolismo , Animais , Proteínas do Citoesqueleto/metabolismo , Giro Denteado/citologia , Giro Denteado/fisiologia , Potenciais Pós-Sinápticos Excitadores , Potenciais Pós-Sinápticos Inibidores , Lipoilação , Masculino , Camundongos , Proteínas do Tecido Nervoso/metabolismo , Neurônios/metabolismo , Neurônios/fisiologia , Domínios Proteicos , Receptores de AMPA/química , Receptores de AMPA/genéticaRESUMO
Synaptic AMPAR expression controls the strength of excitatory synaptic transmission and plasticity. An excess of synaptic AMPARs leads to epilepsy in response to seizure-inducible stimulation. The appropriate regulation of AMPARs plays a crucial role in the maintenance of the excitatory/inhibitory synaptic balance; however, the detailed mechanisms underlying epilepsy remain unclear. Our previous studies have revealed that a key modification of AMPAR trafficking to and from postsynaptic membranes is the reversible, posttranslational S-palmitoylation at the C-termini of receptors. To clarify the role of palmitoylation-dependent regulation of AMPARs in vivo, we generated GluA1 palmitoylation-deficient (Cys811 to Ser substitution) knock-in mice. These mutant male mice showed elevated seizure susceptibility and seizure-induced neuronal activity without impairments in synaptic transmission, gross brain structure, or behavior at the basal level. Disruption of the palmitoylation site was accompanied by upregulated GluA1 phosphorylation at Ser831, but not at Ser845, in the hippocampus and increased GluA1 protein expression in the cortex. Furthermore, GluA1 palmitoylation suppressed excessive spine enlargement above a certain size after LTP. Our findings indicate that an abnormality in GluA1 palmitoylation can lead to hyperexcitability in the cerebrum, which negatively affects the maintenance of network stability, resulting in epileptic seizures.SIGNIFICANCE STATEMENT AMPARs predominantly mediate excitatory synaptic transmission. AMPARs are regulated in a posttranslational, palmitoylation-dependent manner in excitatory synapses of the mammalian brain. Reversible palmitoylation dynamically controls synaptic expression and intracellular trafficking of the receptors. Here, we generated GluA1 palmitoylation-deficient knock-in mice to clarify the role of AMPAR palmitoylation in vivo We showed that an abnormality in GluA1 palmitoylation led to hyperexcitability, resulting in epileptic seizure. This is the first identification of a specific palmitoylated protein critical for the seizure-suppressing process. Our data also provide insight into how predicted receptors such as AMPARs can effectively preserve network stability in the brain. Furthermore, these findings help to define novel key targets for developing anti-epileptic drugs.
Assuntos
Hipocampo/metabolismo , Hipocampo/fisiopatologia , Palmitatos/metabolismo , Receptores de AMPA/deficiência , Convulsões/metabolismo , Convulsões/fisiopatologia , Animais , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Técnicas de Cultura de Órgãos , Receptores de AMPA/genética , Convulsões/genéticaRESUMO
The mammalian brain undergoes sexual differentiation by gonadal hormones during the perinatal critical period. However, the machinery at earlier stages has not been well studied. We found that Ptf1a is expressed in certain neuroepithelial cells and immature neurons around the third ventricle that give rise to various neurons in several hypothalamic nuclei. We show that conditional Ptf1a-deficient mice (Ptf1a cKO) exhibit abnormalities in sex-biased behaviors and reproductive organs in both sexes. Gonadal hormone administration to gonadectomized animals revealed that the abnormal behavior is caused by disorganized sexual development of the knockout brain. Accordingly, expression of sex-biased genes was severely altered in the cKO hypothalamus. In particular, Kiss1, important for sexual differentiation of the brain, was drastically reduced in the cKO hypothalamus, which may contribute to the observed phenotypes in the Ptf1a cKO. These findings suggest that forebrain Ptf1a is one of the earliest regulators for sexual differentiation of the brain.
Assuntos
Prosencéfalo/embriologia , Diferenciação Sexual , Fatores de Transcrição/metabolismo , Animais , Linhagem da Célula , Embrião de Mamíferos/metabolismo , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Gônadas/anormalidades , Hipotálamo/embriologia , Hipotálamo/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Camundongos Knockout , Diferenciação Sexual/genética , Comportamento Sexual Animal , Fatores de Transcrição/deficiênciaRESUMO
PURPOSE: To determine the effects of an intravitreal injection of ranibizumab (IVR) on the choroidal structure and blood flow in eyes with diabetic macular edema (DME). METHODS: Twenty-eight consecutive patients with DME who received an IVR and 20 non-diabetic, age-matched controls were followed for 1 month. The eyes with DME were divided into those with prior panretinal photocoagulation (PRP, n = 16) and those without prior PRP (no-PRP, n = 12). The enhanced depth imaging optical coherence tomography (EDI-OCT) scans and Niblack's image binarization were performed to determine the choroidal structure. The choroidal blood flow was determined by laser speckle flowgraphy. RESULTS: The subfoveal choroidal thickness at the baseline was significantly thicker in the no-PRP group than in the PRP-treated group. After IVR, the best-corrected visual acuity (BCVA) and central retinal thickness in eyes with DME were significantly improved compared to the baseline values. There were significant differences in the choroidal thickness, total choroidal area, and choroidal vascularity index between the groups after IVR. Choroidal vascular index and choroidal blood flow were significantly reduced only in the no-PRP group and not in the PRP-treated group. In addition, the correlation between the central retinal thickness and the choroidal blood flow was significant in the no-PRP group (r = 0.47, P < 0.05). CONCLUSIONS: A single IVR will reduce the central retinal thickness and improve the BCVA in eyes with DME in both the no-PRP and PRP-treated group. IVR affected the choroidal vasculature and blood flow significantly, and a significant correlation was found between the central retinal thickness and the choroidal blood flow in eyes without PRP.
Assuntos
Inibidores da Angiogênese/uso terapêutico , Corioide/irrigação sanguínea , Corioide/patologia , Retinopatia Diabética/tratamento farmacológico , Edema Macular/tratamento farmacológico , Ranibizumab/uso terapêutico , Fluxo Sanguíneo Regional/fisiologia , Idoso , Velocidade do Fluxo Sanguíneo/fisiologia , Retinopatia Diabética/fisiopatologia , Feminino , Angiofluoresceinografia , Seguimentos , Humanos , Injeções Intravítreas , Fotocoagulação a Laser , Fluxometria por Laser-Doppler , Edema Macular/fisiopatologia , Masculino , Pessoa de Meia-Idade , Tomografia de Coerência Óptica , Fator A de Crescimento do Endotélio Vascular/antagonistas & inibidores , Acuidade Visual/fisiologiaRESUMO
We investigated the association between von Willebrand factor (VWF) and exudative age-related macular degeneration (AMD) in 114 Japanese patients. Intravitreal injection of vascular endothelial growth factor (VEGF) inhibitor is the most effective therapy for AMD. Therefore, we analyzed changes of VWF antigen (VWF:Ag) and VWF multimers (VWFMs) after intravitreal injection of aflibercept, an anti-VEGF antagonist. The relationship between polymorphisms in complement factor H (p.Y402H and p.I62V) and AMD was previously reported. In our patients, p.I62V, but not p.Y402H, was significantly associated with an increased risk of AMD. Pre-treatment plasma levels of VWF:Ag in patients with AMD were significantly higher than those in controls. Unusually large VWFMs (UL-VWFMs) were detected in the majority of AMD patients with concurrent vitreous or subretinal hemorrhage. After intravitreal injection of aflibercept, plasma levels of VWF:Ag and VEGF-A were significantly decreased. UL-VWFMs disappeared after aflibercept injection in three cases, but persisted even 1 month after injection in the other five cases. In conclusion, plasma VWF:Ag levels were significantly elevated in patients with AMD, and decreased after intravitreal aflibercept injection. VWF may play an important role in the pathophysiology of AMD, and aflibercept might improve AMD by reducing plasma levels of VWF in addition to VEGF-A.