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1.
Nutrients ; 15(7)2023 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-37049468

RESUMO

Cellular senescence induces inflammation and is now considered one of the causes of organismal aging. Accumulating evidence indicates that age-related deterioration of mitochondrial function leads to an increase in reactive oxygen species (ROS) and DNA damage, which in turn causes cellular senescence. Thus, it is important to maintain mitochondrial function and suppress oxidative stress in order to inhibit the accumulation of senescent cells. Sesamin and its isomer episesamin are types of lignans found in sesame oil, and after being metabolized in the liver, their metabolites have been reported to exhibit antioxidant properties. However, their effects on cellular senescence remain unknown. In this study, the effects of sesamin, episesamin, and their metabolites SC1 and EC1-2 on replicative senescence were evaluated using human diploid lung fibroblasts, and TIG-3 cells. The results showed that sesamin and episesamin treatment had no effect on proliferative capacity compared to the untreated late passage group, whereas SC1 and EC1-2 treatment improved proliferative capacity and mitigated DNA damage of TIG-3 cells. Furthermore, other cellular senescence markers, such as senescence-associated secretory phenotype (SASP), mitochondria-derived ROS, and mitochondrial function (ROS/ATP ratio) were also reduced by SC1 and EC1-2 treatment. These results suggest that SC1 and EC1-2 can maintain proper mitochondrial function and suppress the induction of cellular senescence.


Assuntos
Lignanas , Fígado , Humanos , Espécies Reativas de Oxigênio/metabolismo , Fígado/metabolismo , Lignanas/farmacologia , Lignanas/metabolismo , Senescência Celular
2.
Neurosurg Rev ; 46(1): 85, 2023 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-37058150

RESUMO

Optical coherence tomography (OCT) is a useful tool for predicting visual recovery after the removal of pituitary tumors. However, the utility of OCT in patients with pituitary tumors and a normal visual field is unclear. We aimed to analyze OCT features in pituitary tumors without visual field defects. Pituitary tumors without visual field defects were selected. A total of 138 eyes from 69 patients, assessed by the Humphrey visual field test and OCT, were enrolled in this study. Using preoperative coronal sections of MR images, patients were divided into chiasmal compression (CC) and non-chiasmal compression (non-CC) groups, and OCT characteristics were examined. The CC and non-CC groups consisted of 40 and 29 patients, respectively. There were no differences in age, sex, tumor type, or degree of visual field testing, but the tumor size was different between the two groups. On OCT, macular thickness ganglion cell complex (mGCC) was significantly thinner in the CC group than that in the non-CC group (112.5 vs 117.4 um, P < 0.05). Based on a database of healthy participants, 24% and 2% of eyes in the CC and non-CC groups had abnormal mGCC thickness (P < 0.01), respectively. In a sub-analysis of the CC group, patients with an abnormal mGCC thickness were older than a normal one (58.2 vs 41.1 years, p < 0.01). OCT can detect early optic nerve damage due to optic CC by pituitary tumors, even in normal visual fields. The degree of mGCC thinning may provide an appropriate surgical timing for pituitary tumors that compress the optic chiasm.


Assuntos
Traumatismos do Nervo Óptico , Neoplasias Hipofisárias , Humanos , Testes de Campo Visual , Campos Visuais , Tomografia de Coerência Óptica/métodos , Neoplasias Hipofisárias/complicações , Neoplasias Hipofisárias/diagnóstico por imagem , Neoplasias Hipofisárias/cirurgia , Células Ganglionares da Retina/patologia , Transtornos da Visão/etiologia , Quiasma Óptico/diagnóstico por imagem
3.
Neuroophthalmology ; 45(5): 320-323, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34483410

RESUMO

Recurrent painful ophthalmoplegic neuropathy (RPON) is a rare disorder, which typically occurs in children, and causes headaches and unilateral oculomotor palsy. Early high-dose corticosteroid therapy is recommended to rapidly resolve acute episodes. However, the pathophysiology and therapeutic options for this disorder remain to be fully elucidated. We report a case with typical clinical features of RPON successfully treated with beta-blocker eye drop instillation after the effects of high-dose corticosteroid and other therapies were not sufficient. We propose that beta-blocker eye drop instillation should be considered for patients with corticosteroid-resistant RPON.

4.
Transl Vis Sci Technol ; 9(5): 8, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32821480

RESUMO

Purpose: We assessed the ability to detect preperimetric glaucoma (PPG) based on asymmetry in the thickness of the macular inner retinal layers measured by spectral-domain optical coherence tomography. Methods: We studied 45 normal eyes and 50 PPG eyes retrospectively. Three-dimensional optical coherence tomography macular area scans were used to obtain the thickness of the retinal nerve fiber layer (RNFL), ganglion cell layer/inner plexiform layer (GCL/IPL), and ganglion cell complex (GCC). We calculated the thickness differences between the upper and lower macular hemispheres for the corresponding superpixels, then evaluated the mean absolute value of the thickness differences and the number of superpixels in which the thickness difference was greater than X µm, where X is an integer number from 1 to 10. Areas under the receiver operating characteristic curves (AUCs) for their PPG diagnostic performances were compared to the average thickness measurements of the total and hemiretinal sectors. X was determined at the maximum AUC value. Results: The AUC for the mean absolute value of the difference in GCL/IPL thickness (0.923) was higher than the difference in RNFL and GCC thickness (0.710 and 0.905, respectively). The AUC for the number of superpixels in which the GCL/IPL thickness difference was greater than 8 µm (X = 8) was 0.914. The ability to diagnose PPG using these GCL/IPL parameters was statistically higher than for total or superior and inferior hemiretinal GCL/IPL thicknesses. Conclusions: Asymmetry in the thickness of the GCL/IPL shows good PPG diagnostic performance. Translational Relevance: This approach would be useful in the early detection of glaucoma.


Assuntos
Glaucoma , Macula Lutea , Animais , Glaucoma/diagnóstico , Pressão Intraocular , Macula Lutea/diagnóstico por imagem , Fibras Nervosas , Células Ganglionares da Retina , Estudos Retrospectivos , Tomografia de Coerência Óptica
5.
NPJ Sci Food ; 4: 4, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32133417

RESUMO

Sesamin [(7α,7'α,8α,8'α)-3,4:3',4'-bis(methylenedioxy)-7,9':7',9-diepoxylignane] is a major lignan in sesame seeds. Sesamin is converted to the catechol metabolite, SC1 [(7α,7'α,8α,8'α)-3',4'-methylenedioxy-7,9':7',9-diepoxylignane-3,4-diol] with anti-inflammatory effects after oral administration. However, its molecular target remains unknown. Analysis using high-performance affinity nanobeads led to the identification of annexin A1 (ANX A1) as an SC1-binding protein. SC1 was found to bind to the annexin repeat 3 region of ANX A1 with a high-affinity constant (Kd = 2.77 µmol L-1). In U937 cells, SC1 exhibited an anti-inflammatory effect dependent on ANX A1. Furthermore, administration of sesamin or SC1 attenuated carbon tetrachloride-induced liver damage in mice and concurrently suppressed inflammatory responses dependent on ANX A1. The mechanism involved SC1-induced ANX A1 phosphorylation at serine 27 that facilitates extracellular ANX A1 release. Consequently, the ANX A1 released into the extracellular space suppressed the production of tumor necrosis factor α. This study demonstrates that ANX A1 acts as a pivotal target of sesamin metabolites to attenuate inflammatory responses.

6.
Nutrients ; 11(7)2019 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-31336975

RESUMO

Sesame lignans, which are biologically active compounds present in sesame seeds and oil, are known to have neuroprotective effects in several models of brain dysfunction. However, the effects of sesame lignans on age-related brain dysfunction are not clear and were thus investigated in the present study using a senescence-accelerated mouse (SAMP10). Two-month-old male SAMP10 mice were administrated a basal diet with 0% or 0.05% sesame lignans for two months, or with 0%, 0.02%, or 0.05% sesame lignans for 10 months and subjected to step-through passive avoidance tasks and forced swim tests. Reactive carbonyl species (RCs) were evaluated as markers of oxidative stress using a recently developed comprehensive analytical method. Both learning time in passive avoidance tasks and immobile time in forced swim tests became longer with aging (p < 0.05). However, the administration of sesame lignans significantly ameliorated age-related effects in both tests (p < 0.05). Age-related increases in RCs such as 4-hydroxy-2-nonenal in the cerebral cortex and liver were reduced in mice fed sesame lignans. These results suggest that sesame lignans can prevent age-related brain dysfunction via anti-oxidative activity.


Assuntos
Disfunção Cognitiva/tratamento farmacológico , Lignanas/farmacologia , Sesamum/química , Envelhecimento , Animais , Peso Corporal/efeitos dos fármacos , Encéfalo/efeitos dos fármacos , Humanos , Lignanas/administração & dosagem , Masculino , Camundongos , Camundongos Endogâmicos , Tamanho do Órgão , Análise de Sobrevida
7.
J Agric Food Chem ; 67(27): 7640-7649, 2019 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-30951310

RESUMO

Sesamin, a representative sesame lignan, has health-promoting activities. Sesamin is converted into catechol derivatives and further into their glucuronides or sulfates in vivo, whereas the biological activities of sesamin metabolites remain unclear. We examined the inhibitory effects of sesamin metabolites on the lipopolysaccharide (LPS)-induced nitric oxide (NO) production in mouse macrophage-like J774.1 cells and found that a monocatechol derivative SC1, (7α,7'α,8α,8'α)-3,4-dihydroxy-3',4'-methylenedioxy-7,9':7',9-diepoxylignane, has a much higher activity than sesamin and other metabolites. The inhibitory effects of SC1 glucuronides were time-dependently enhanced, associated with the intracellular accumulation of SC1 and the methylated form. SC1 glucuronides and SC1 attenuated the expression of inducible NO synthase (iNOS) and upstream interferon-ß (IFN-ß) in the LPS-stimulated macrophages. The inhibitory effects of SC1 glucuronides against NO production were canceled by the ß-glucuronidase inhibitor and enhanced by the catechol-O-methyltransferase inhibitor. Our results suggest that SC1 glucuronides exert the anti-inflammatory effects by inhibiting the IFN-ß/iNOS signaling through macrophage-mediated deconjugation.


Assuntos
Anti-Inflamatórios , Catecóis/farmacologia , Dioxóis/farmacologia , Glucuronídeos/farmacologia , Interferon beta/antagonistas & inibidores , Lignanas/farmacologia , Óxido Nítrico Sintase Tipo II/antagonistas & inibidores , Animais , Catecol O-Metiltransferase/metabolismo , Catecóis/química , Catecóis/metabolismo , Linhagem Celular , Sistema Enzimático do Citocromo P-450/metabolismo , Dioxóis/metabolismo , Glucuronidase/metabolismo , Glucuronídeos/química , Lignanas/metabolismo , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Camundongos , Estrutura Molecular
8.
Invest Ophthalmol Vis Sci ; 60(2): 677-684, 2019 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-30786279

RESUMO

Purpose: To investigate the effect of trabeculectomy on the waveform changes of laser speckle flowgraphy (LSFG) in the optic nerve head (ONH) in patients with glaucoma. Methods: Forty-eight eyes of 48 patients with open angle glaucoma were included in this prospective study. LSFG was performed before and 1, 3, and 6 months after trabeculectomy. Longitudinal changes in average mean blur rate (MBR), blow out score (BOS), resistivity index (RI), falling rate, skew, acceleration time index, and blow out time in the tissue area of the ONH were analyzed by using mixed-effects models. Results: Intraocular pressure (IOP) decreased and ocular perfusion pressure increased significantly at each postoperative time point (P < 0.001, each). BOS increased (P < 0.001, each) and RI decreased (P < 0.001, each) significantly at each postoperative time point, although average MBR and other waveform parameters did not change significantly. Multivariate analyses revealed that younger age (coefficients = -0.13 and 0.0014, P = 0.006 and 0.03 for BOS change and RI change, respectively), worse baseline mean deviation of visual fields (coefficients = -0.18 and 0.0026, P = 0.009 and 0.005), larger IOP reduction (coefficients = -0.29 and 0.0037, P < 0.001, each), and larger pulse rate increase (coefficients = 0.17 and -0.0024, P < 0.001, each) are significantly associated with postoperative BOS increase and RI decrease. Conclusions: Given that postoperative BOS increased and RI decreased with the average MBR remaining unchanged, IOP reduction by trabeculectomy may contribute to stable blood flow throughout the duration of the heartbeat in the tissue area of the ONH.


Assuntos
Glaucoma de Ângulo Aberto/fisiopatologia , Glaucoma de Ângulo Aberto/cirurgia , Pressão Intraocular/fisiologia , Disco Óptico/irrigação sanguínea , Vasos Retinianos/fisiologia , Trabeculectomia/métodos , Idoso , Velocidade do Fluxo Sanguíneo , Feminino , Gonioscopia , Frequência Cardíaca/fisiologia , Humanos , Fluxometria por Laser-Doppler , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Fluxo Sanguíneo Regional/fisiologia , Tonometria Ocular , Campos Visuais
9.
Clin Ophthalmol ; 11: 1617-1624, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28979091

RESUMO

PURPOSE: We conducted a prospective study in patients with normal-tension glaucoma (NTG) who received either isopropyl unoprostone or latanoprost. We compared the drugs in terms of their effects on intraocular pressure (IOP) and visual field loss progression over a 3-year period. STUDY DESIGN: Prospective, randomized controlled study. METHODS: We enrolled 48 patients with newly diagnosed NTG at Kanazawa University Hospital. Eligible patients were randomly allocated (1:1) to receive either unoprostone or latanoprost ophthalmic solutions. The primary outcomes were IOP changes and visual field deterioration within 36 months. Visual field changes were analyzed: the cumulative survival rates were calculated in terms of mean deviation, pattern standard deviation, and total deviation of the upper or lower hemi-visual field, each visual field sector, and guided progression analysis. In addition, we evaluated the progression of glaucomatous optic disc changes using fundus photography and confocal scanning laser ophthalmoscopy. RESULTS: The mean pretreatment IOP was 15.0±2.4 mmHg in the Unoprostone group and 15.2±1.9 mmHg in the Latanoprost group. The mean IOP during the treatment period was 13.7±2.3 mmHg in the Unoprostone group and 13.0±1.8 mmHg in the Latanoprost group. In both groups, the IOP decreased significantly (p<0.001) from baseline after treatment. The posttreatment IOP values were significantly lower in the Latanoprost group than in the Unoprostone group (p=0.023). Regarding the 3-year cumulative survival rate of visual field loss progression, there were no significant differences between groups in any parameters of the visual field or guided progression analysis. There were no significant differences between groups in disc changes. CONCLUSIONS: No significant differences were found between groups with regard to the visual field and structural progression in patients with NTG, although unoprostone was less effective than latanoprost in lowering the IOP.

10.
Exp Physiol ; 100(11): 1319-30, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26300535

RESUMO

NEW FINDINGS: What is the central question of this study? Our aim was to examine whether sesamin can prevent a decline in exercise capacity in high-fat diet-induced diabetic mice. Our hypothesis was that maintenance of mitochondrial function and attenuation of oxidative stress in the skeletal muscle would contribute to this result. What is the main finding and its importance? The new findings are that sesamin prevents the diabetes-induced decrease in exercise capacity and impairment of mitochondrial function through the inhibition of NAD(P)H oxidase-dependent oxidative stress in the skeletal muscle. Sesamin may be useful as a novel agent for the treatment of diabetes mellitus. ABSTRACT: We previously reported that exercise capacity and skeletal muscle mitochondrial function in diabetic mice were impaired, in association with the activation of NAD(P)H oxidase. It has been reported that sesamin inhibits NAD(P)H oxidase-induced superoxide production. Therefore, we examined whether the antioxidant sesamin could prevent a decline in exercise capacity in mice with high-fat diet (HFD)-induced diabetes. C57BL/6J mice were fed a normal diet (ND) or HFD, then treated or not with sesamin (0.2%) to yield the following four groups: ND, ND+Sesamin, HFD and HFD+Sesamin (n = 10 each). After 8 weeks, body weight, fat weight, blood glucose, insulin, triglyceride, total cholesterol and fatty acid were significantly increased in HFD compared with ND mice. Sesamin prevented the increases in blood insulin and lipid levels in HFD-fed mice, but did not affect the plasma glucose. Exercise capacity determined by treadmill tests was significantly reduced in HFD mice, but almost completely recovered in HFD+Sesamin mice. Citrate synthase activity was significantly decreased in the skeletal muscle of HFD mice, and these decreases were also inhibited by sesamin. Superoxide anion and NAD(P)H oxidase activity were significantly increased in HFD mice compared with the ND mice and were ameliorated by sesamin. Sesamin prevented the decline in exercise capacity in HFD-induced diabetic mice via maintenance of mitochondrial function, fat oxidation and attenuation of oxidative stress in the skeletal muscle. Our data suggest that sesamin may be useful as a novel agent for the treatment of diabetes mellitus.


Assuntos
Diabetes Mellitus Experimental/fisiopatologia , Dioxóis/farmacologia , Lignanas/farmacologia , Mitocôndrias Musculares/patologia , Músculo Esquelético/fisiopatologia , Condicionamento Físico Animal , Animais , Peso Corporal , Linhagem Celular , Diabetes Mellitus Experimental/tratamento farmacológico , Dieta Hiperlipídica , Tolerância ao Exercício , Masculino , Camundongos Endogâmicos C57BL , NADPH Oxidases/metabolismo , Estresse Oxidativo , Superóxidos/metabolismo
11.
Glob J Health Sci ; 7(6): 1-10, 2015 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-26153159

RESUMO

Sesamin has anti-oxidative functions in vivo. Fatigue is caused in part by oxidative stress. We evaluated whether sesame lignans (sesamin/episesamin=1/1, 10 mg) with vitamin E (55 mg of alpha-tocopherol) (SVE) could improve subjective statuses and anti-oxidative capacity in humans using questionnaires on fatigue, sleep and physical appearance, as well as low-density lipoprotein oxidation lag time. A placebo-controlled, double-blind, parallel-group study was conducted with subjects experiencing daily fatigue. After a run-in period, subjects were administered oral SVE or a placebo (P) for 8 weeks. A questionnaire regarding fatigue, sleep and physical appearance was conducted at 0, 4, and 8 weeks. Plasma low-density lipoprotein oxidation lag time was measured as an indicator of anti-oxidative capacity. The per-protocol analysis revealed significant improvements in fatigue status at 4 and 8 weeks compared to 0 weeks in both groups (p<0.01), and sleep and physical appearance at 8 weeks compared to 0 weeks only in the SVE group (p<0.01). There were no significant differences observed between the groups. According to the 72-subject subgroup analysis (aged 40 and over), the sleep and physical appearance significantly improved compared to the P group (p<0.05), and fatigue status showed a tendency for improvement compared to the P group. Anti-oxidative capacity in the SVE group significantly increased compared to the P group (p<0.01). No adverse events relating to SVE supplementation were confirmed. These results suggest SVE supplementation could safely alleviate daily fatigue and oxidative stress.


Assuntos
Antioxidantes/uso terapêutico , Fadiga/tratamento farmacológico , Lignanas/uso terapêutico , Sesamum , Vitamina E/uso terapêutico , Adulto , Método Duplo-Cego , Feminino , Humanos , Masculino , Estresse Oxidativo , Inquéritos e Questionários , Resultado do Tratamento
12.
Nippon Ganka Gakkai Zasshi ; 119(5): 354-62, 2015 May.
Artigo em Japonês | MEDLINE | ID: mdl-26062392

RESUMO

PURPOSE: We report two cases of Vogt-Koyanagi-Harada disease (VKH) in which shallow anterior chambers were improved after steroid pulse therapy. CASE: The patients were women aged 65 and 72. They had headaches, decreased visual acuity and shallow anterior chamber in both eyes. There was no inflammation in the anterior chamber. Ultrasound biomicroscopy (UBM) showed ciliary edema, ciliochoroidal detachment, and angle closure. One case showed high intraocular pressure (IOP), and a diagnosis of acute primary angle closure was made. Although cataract surgery was performed in the left eye, postoperative optical coherence tomography (OCT) revealed serous retinal detachment in both eyes. The shallow anterior chamber and UBM findings were improved and serous retinal detachment disappeared after steroid pulse therapy in both cases. CONCLUSION: VKH may cause shallow anterior chamber and angle closure. The inflammatory changes of VKH in the anterior segment, i. e. ciliary edema and ciliochoroidal detachment, may exacerbate the shallow anterior chambers and narrow angles and result in an acute increase in IOP in eyes with short axial length. VKH associated with shallow anterior chamber may be misdiagnosed as acute primary angle closure. For differential diagnosis, examinations of the ocular fundus including OCT are useful.


Assuntos
Câmara Anterior/patologia , Descolamento Retiniano/patologia , Síndrome Uveomeningoencefálica/patologia , Idoso , Segmento Anterior do Olho/patologia , Feminino , Humanos , Inflamação/tratamento farmacológico , Inflamação/patologia , Descolamento Retiniano/diagnóstico , Descolamento Retiniano/tratamento farmacológico , Resultado do Tratamento , Síndrome Uveomeningoencefálica/diagnóstico , Síndrome Uveomeningoencefálica/tratamento farmacológico , Acuidade Visual/fisiologia
13.
J Cell Biol ; 169(3): 527-38, 2005 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-15883201

RESUMO

Tight junction (TJ)-like structures have been reported in Schwann cells, but their molecular composition and physiological function remain elusive. We found that claudin-19, a novel member of the claudin family (TJ adhesion molecules in epithelia), constituted these structures. Claudin-19-deficient mice were generated, and they exhibited behavioral abnormalities that could be attributed to peripheral nervous system deficits. Electrophysiological analyses showed that the claudin-19 deficiency affected the nerve conduction of peripheral myelinated fibers. Interestingly, the overall morphology of Schwann cells lacking claudin-19 expression appeared to be normal not only in the internodal region but also at the node of Ranvier, except that TJs completely disappeared, at least from the outer/inner mesaxons. These findings have indicated that, similar to epithelial cells, Schwann cells also bear claudin-based TJs, and they have also suggested that these TJs are not involved in the polarized morphogenesis but are involved in the electrophysiological "sealing" function of Schwann cells.


Assuntos
Axônios/patologia , Proteínas de Membrana/genética , Fibras Nervosas Mielinizadas/patologia , Nervos Periféricos/anormalidades , Células de Schwann/patologia , Junções Íntimas/patologia , Animais , Axônios/metabolismo , Axônios/ultraestrutura , Membrana Celular/metabolismo , Membrana Celular/patologia , Membrana Celular/ultraestrutura , Claudinas , Feminino , Masculino , Proteínas de Membrana/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Bainha de Mielina/metabolismo , Bainha de Mielina/patologia , Bainha de Mielina/ultraestrutura , Fibras Nervosas Mielinizadas/metabolismo , Fibras Nervosas Mielinizadas/ultraestrutura , Condução Nervosa/genética , Nervos Periféricos/metabolismo , Nervos Periféricos/ultraestrutura , Nós Neurofibrosos/metabolismo , Nós Neurofibrosos/patologia , Nós Neurofibrosos/ultraestrutura , Células de Schwann/metabolismo , Células de Schwann/ultraestrutura , Junções Íntimas/metabolismo , Junções Íntimas/ultraestrutura
14.
EMBO J ; 24(7): 1477-88, 2005 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-15775964

RESUMO

The L1 family of cell adhesion molecules is predominantly expressed in the nervous system. Mutations in human L1 cause neuronal diseases such as HSAS, MASA, and SPG1. Here we show that sax-7 gene encodes an L1 homologue in Caenorhabditis elegans. In sax-7 mutants, the organization of ganglia and positioning of neurons are abnormal in the adult stage, but these abnormalities are not observed in early larval stage. Misplacement of neurons in sax-7 mutants is triggered by mechanical force linked to body movement. Short and long forms of SAX-7 exhibited strong and weak homophilic adhesion activities in in vitro aggregation assay, respectively, which correlated with their different activities in vivo. SAX-7 was localized on plasma membranes of neurons in vivo. Expression of SAX-7 only in a single neuron in sax-7 mutants cell-autonomously restored its normal neuronal position. Expression of SAX-7 in two different head neurons in sax-7 mutants led to the forced attachment of these neurons. We propose that both homophilic and heterophilic interactions of SAX-7 are essential for maintenance of neuronal positions in organized ganglia.


Assuntos
Proteínas de Caenorhabditis elegans/metabolismo , Caenorhabditis elegans/metabolismo , Gânglios dos Invertebrados/metabolismo , Moléculas de Adesão de Célula Nervosa/metabolismo , Neurônios/metabolismo , Animais , Baculoviridae , Western Blotting , Bombyx , Proteínas de Caenorhabditis elegans/genética , Adesão Celular/fisiologia , Agregação Celular/genética , Agregação Celular/fisiologia , Células Cultivadas , Clonagem Molecular , DNA Complementar/genética , Componentes do Gene , Vetores Genéticos , Proteínas de Fluorescência Verde , Proteínas de Membrana/metabolismo , Modelos Biológicos , Mutação/genética , Molécula L1 de Adesão de Célula Nervosa/genética , Moléculas de Adesão de Célula Nervosa/genética , Filogenia
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