Yoshinori Mitamura

The University of Tokushima, Tokusima, Tokushima, Japan

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Publications (144)291.32 Total impact

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    ABSTRACT: We report changes of choroidal structure determined by binarization of enhanced depth imaging optical coherence tomographic (EDI-OCT) images after treatment for primary intraocular lymphoma (PIOL). Five eyes of four patients with PIOL were examined by EDI-OCT before and 6 months after intravitreal methotrexate injections. In addition, 15 eyes of 15 normal individuals controlled by age and refractive error were examined by EDI-OCT. Binarization of the EDI-OCT images was performed using publicly accessible software (ImageJ). The examined area of the subfoveal choroid was 1,500 μm wide, and the dark areas that represented the luminal areas were traced by the Niblack method. Wilcoxon signed rank test was used to determine the significance of changes in the subfoveal choroidal thickness, interstitial area, and luminal area. Mann–Whitney U test was used to compare the parameters in the eyes with pretreatment PIOL and normal control eyes. The subfoveal choroidal thickness was significantly decreased after treatment (P = 0.0431). In the binarized images, the interstitial area was significantly decreased after treatment (P = 0.0431), while the luminal area was not significantly changed (P = 0.8927). After delayed onset of PIOL, increased interstitial area, thickened choroid and unchanged luminal area were observed in one eye. The interstitial area and choroidal thickness were significantly increased in the eyes with pretreatment PIOL compared with the normal control eyes (P = 0.0207, P = 0.0495, respectively), while the luminal area was not significantly different (P = 0.2752). After treatment for PIOL, the EDI-OCT images showed a thinner choroid, and binarization of the EDI-OCT images showed significantly decreased interstitial areas compared with the luminal areas. The binarized EDI-OCT images can provide useful information on choroidal structure in eyes with PIOL, and combining these images with intraocular interleukin levels or fundus autofluorescence images should provide valuable information for determining the PIOL activity.
    Preview · Article · Dec 2015 · BMC Ophthalmology
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    ABSTRACT: To report a thicker choroid and larger choroidal luminal area in an eye with Wyburn-Mason syndrome. To the best of our knowledge, this is the first report demonstrating an increase in the choroidal thickness and the luminal area in a case of Wyburn-Mason syndrome. In addition, we report the changing appearance of retinal arteriovenous malformations over a 16-year period. A 27-year-old woman, who was diagnosed with Wyburn-Mason syndrome at age 11 years, visited our clinic. Her best-corrected visual acuity was 20/12.5 in the right eye and light perception in the left eye. Severely dilated, tortuous vascular loops were distributed from the optic disc over all four quadrants of the left fundus. The vascular loops in some areas were more dilated and tortuous than 16 years earlier. Optical coherence tomography (OCT) showed retinal edema with cystic changes and enlarged choroidal vessel lumens in the left eye. The subfoveal choroidal thickness was manually measured by the caliper function in the enhanced depth imaging OCT (EDI-OCT) images. Binarization of the EDI-OCT images was performed with publicly accessible ImageJ software. The examined area of the subfoveal choroid was 1,500 μm wide, and the dark areas representing the luminal areas were traced by the Niblack method. After determining the distance of each pixel, the luminal area was automatically calculated. The subfoveal choroidal thickness was 250 μm in the right eye and 462 μm in the left eye. The luminal area of the 1,500-μm-wide subfoveal choroid was computed to be 307,165.6 μm(2) in the right eye and 545,780.7 μm(2) in the left eye. The EDI-OCT images showed a thicker choroid, and binarization of the EDI-OCT images showed that the luminal areas were significantly larger in the affected eye, suggesting a dilatation of the choroidal vessels. The results demonstrated that conversion of EDI-OCT images to binary images was a useful method to quantify the choroidal structure.
    Full-text · Article · Dec 2015 · BMC Ophthalmology
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    ABSTRACT: Purpose: To determine whether the choroidal folds in patients with Vogt-Koyanagi-Harada disease can be detected by retromode of a scanning laser ophthalmoscopy (SLO) with infrared laser light source. Methods: The authors examined two patients with Vogt-Koyanagi-Harada disease at the acute stage by retromode imaging scanning laser ophthalmoscopy with an infrared laser before and after steroid treatment. Results: The retromode imaging by scanning laser ophthalmoscopy clearly and noninvasively delineated the choroidal folds in both cases. The folds disappeared after steroid treatment and reappeared with recurrences of uveitis. Conclusion: The retromode imaging by scanning laser ophthalmoscopy can detect the choroidal folds and should be useful for detecting and monitoring the choroidal folds in Vogt-Koyanagi-Harada disease.
    No preview · Article · Oct 2015
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    ABSTRACT: To determine the 2-year results of metamorphopsia, visual acuity, and optical coherence tomographic (OCT) parameters after epiretinal membrane (ERM) removal, and to evaluate the correlations among them. We studied 75 eyes of 75 patients with an ERM who underwent vitrectomy and membrane peeling. The best-corrected visual acuity (BCVA), metamorphopsia scores, and OCT parameters were measured at the baseline, and 1, 3, 6, 9, 12, 18, and 24 months postoperatively. M-CHARTS were used to quantify the degree of metamorphopsia. The mean BCVA, degree of metamorphopsia, and all of the OCT parameters except the photoreceptor outer segment (PROS) length improved significantly from that at the baseline at 24 months (P < 0.001). However, they were not significantly different from those at 12 months. The better BCVA at 24 months was correlated with the longer PROS length at the baseline (P < 0.01). The degree of metamorphopsia at 24 months was significantly correlated with that at baseline (P < 0.01). A postoperative follow-up period of 12 months may be sufficient to assess the improvements induced by the ERM surgery. The preoperative PROS length was the prognostic factor for the postoperative BCVA. The preoperative degree of metamorphopsia was the prognostic factor for the postoperative degree of metamorphopsia, suggesting that surgery for ERM should be performed before development of severe metamorphopsia.
    No preview · Article · Aug 2015 · Albrecht von Graæes Archiv für Ophthalmologie
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    ABSTRACT: Purpose. To evaluate the movement of the anterior and posterior lens poles during naturally stimulated accommodation in children using anterior segment optical coherence tomography (OCT). Methods. This is a prospective, observational, noncomparative case series including 18 eyes of nine children. Analysis of the anterior segment in the accommodated and unaccommodated state (with cycloplegia) was done using anterior segment OCT. The main outcome measures were the position of the anterior and posterior lens poles (in relation to the cornea) and lens thickness (LT). Results. A Statistically significant forward movement of the anterior lens pole and backward movement of the posterior lens pole with an increase in LT were found during accommodation ( P < 0.001 ). There was no significant difference between the degree of movement of the anterior lens pole and the posterior lens pole during accommodation ( P = 0.944 ). Conclusions. Anterior segment OCT provides a rapid noncontact method for studying accommodation in children. The backward movement of the posterior lens pole during accommodation nearly equals the forward movement of its anterior pole. These data minimize the theoretical hydraulic effect of the vitreous during accommodation, adding more support to the capsular theory of Helmholtz.
    Preview · Article · Aug 2015 · Journal of Ophthalmology
  • K. Akaiwa · T. Katome · A. Fujihara · F. Hotta · T. Naito · Y. Mitamura
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    ABSTRACT: Purpose: To report the outcome of reduced-fluence photodynamic therapy for multiple posterior pigment epitheliopathy (MPPE) in 4 eyes of 2 cases. Cases: Both were males aged 61 and 67 years respectively. One case had been receiving peroral corticosteroid for one year. The other had had multiple osteoma and been treated by peroral prednisolone for 10 years. He had been diagnosed with MPPE 3 years before. Multiple sessions of photocoagulation were ineffective. Findings and Clinical Course: Both cases were diagnosed with bilateral MPPE. One case had cystoid macular edema. The affected 4 eyes received reduced-fluence photodynamic therapy using one-half dosis of verteporfin. Three eyes showed reduction of serous retinal detachment and subfoveal choroidal thickness. Visual acuity improved in 2 eyes. One eye failed to respond to treatment. Conclusion: Reduced-fluence photodynamic therapy was effective in 3 out of 4 eyes with multiple posterior pigment epitheliopathy. The treatment was ineffective in one eye.
    No preview · Article · Jul 2015
  • H. Sano · T. Katome · F. Hotta · T. Naito · Y. Mitamura
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    ABSTRACT: Purpose: To report a case of white retinal patches after vitreous surgery for rhegmatogenous retinal detachment. Case: A 45-year-old male was referred to us for rhegmatogenous retinal detachment in the right eye. Findings: Corrected visual acuity was 0.02 in the affected eye. A retinal break was present in the superior temporal periphery, with retinal detachment extending to the macula. The right eye received vitreous surgery, evacuation of subretinal fluid through the retinal break, and vitreous-air exchange followed by injection of sulfur fluoride. The retina became reattached the following day. When seen 2 weeks after surgery, numerous white patches were located along the previous border of retinal detachment. The patches showed intense autofluorescence. The spontaneously resolved 12 weeks after surgery. Conclusion: The white patches seen in the present case may have derived from material originating from outer segments of photoreceptors in the residual subretinal fluid.
    No preview · Article · Jun 2015
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    ABSTRACT: We describe a case of untreated adult-onset Coats' disease with a proliferative epiretinal membrane (ERM) treated successfully with 25-gauge pars plana vitrectomy (25GPPV). A 26-year-old man presented with a 3-week history of decreased vision in his left eye. At the initial examination, the decimal best-corrected visual acuity (BCVA) was 0.7 in the left eye. Ophthalmoscopy revealed the typical appearance of Stage 2A Coats' disease but with a proliferative ERM in the posterior pole. The patient received 2 monthly intravitreal injections of 2.5 mg bevacizumab, 5 laser photocoagulations to the area of telangiectasia, and 1 session of cryoretinopexy. Nine months after the initial visit, a traction by the ERM on the parafoveal area developed causing macular edema which reduced the BCVA to 0.3. He underwent 25GPPV with the removal of the ERM. In addition, the peripheral telangiectasia was treated intraoperatively with both laser photocoagulation and cryoretinopexy. Postoperatively, the traction to the parafoveal area was released and the BCVA improved to 0.6 which remained stable during the follow-up period of 13 months. We conclude that 25GPPV combined with ERM peeling, laser photocoagulation, and cryoretinopexy can be effective for adult-onset Coats' disease associated with an ERM. J. Med. Invest. 62: 85-88, February, 2015.
    Preview · Article · Mar 2015 · The Journal of Medical Investigation
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    ABSTRACT: To investigate the surfaces and principal elements of the colorants of cosmetically tinted contact lenses (Cos-CLs). We analyzed the surfaces and principal elements of the colorants of five commercially available Cos-CLs using scanning electron microscopy with energy-dispersive x-ray analysis. In two Cos-CLs, the anterior and posterior surfaces were smooth, and colorants were found inside the lens. One lens showed colorants located to a depth of 8 to 14 μm from the anterior side of the lens. In the other lens, colorants were found in the most superficial layer on the posterior surface, although a coated layer was observed. The colorants in the other three lenses were deposited on either lens surface. Although a print pattern was uniform in embedded type lenses, uneven patterns were apparent in dot-matrix design lenses. Colorants used in all lenses contained chlorine, iron, and titanium. In the magnified scanning electron microscopy images of a certain lens, chlorine is exuded and spread. Cosmetically tinted contact lenses have a wide variety of lens surfaces and colorants. Colorants may be deposited on the lens surface and consist of an element that has tissue toxicity.This is an open-access article distributed under the terms of the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License, where it is permissible to download and share the work provided it is properly cited. The work cannot be changed in any way or used commercially.
    Preview · Article · Mar 2015 · Eye & contact lens
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    ABSTRACT: Purpose: To report the effect of palliative radiotherapy in a case of advanced sebaceous carcinoma presumably originating from the lacrimal gland. Case: A 37-year-old male presented with proptosis of the right eye since 6 months before associated with pain. Corrected visual acuity was 1.2 right and visual acuity was 1.5 (n.c.) left. Computed tomography showed right orbital tumor with bone destruction. Positron emitting tomography-computed tomography showed metastasis to the lymph glands and multiple osseous metastases. The patient elected palliative therapy only. The pain increased 4 months later, necessitating radiotherapy totaling 39 Gy. The orbital lesion decreased together with improved cosmetic outlook and decreased pain. The effect lasted until the patient died of pancytopenia 8 months after his first visit. Conclusion: Palliative radiotherapy was effective for advanced carcinoma of sebaceous gland and improved quality of life.
    No preview · Article · Mar 2015
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    ABSTRACT: Optic neuritis is inflammation of the optic nerve and is strongly associated with multiple sclerosis (MS), an inflammatory demyelinating syndrome of the central nervous system. It leads to retinal ganglion cell (RGC) death and can cause severe vision loss. Brimonidine (BMD) is a selective α2-adrenergic receptor agonist that is used clinically for the treatment of glaucoma. BMD lowers intraocular pressure, but recent evidence suggests that its therapeutic efficacy may also mediate through mechanisms independent of modulation of intraocular pressure. In this study, we examined the effects of topical administration of BMD on retinal degeneration during optic neuritis in experimental autoimmune encephalomyelitis (EAE), an animal model of MS. EAE was induced with MOG35-55 in C57BL/6J mice and BMD eyedrops were applied daily. In the EAE retina, the number of RGCs was significantly decreased and this effect was suppressed with BMD treatment. Consistent with histological analyses, the visual impairment observed in EAE mice was inhibited with BMD treatment, indicating the functional significance of the neuroprotective effect of BMD. Furthermore, BMD increased the expression level of basic fibroblast growth factor in the EAE retina, particularly in Müller glial cells and RGCs. Our findings suggest that topical administration of BMD may be available for RGC protection during optic neuritis, as well as for glaucoma. Copyright © 2015. Published by Elsevier Ireland Ltd.
    Full-text · Article · Feb 2015 · Neuroscience Letters
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    ABSTRACT: To determine the correlation between the changes in metamorphopsia in daily life environment and the M-CHARTS scores after epiretinal membrane (ERM) removal, and to determine the criterion for determining whether clinically significant changes in the metamorphopsia score have occurred in M-CHARTS. We studied 65 eyes undergoing vitrectomy for unilateral ERM. Self-administered questionnaires were used to examine the metamorphopsia in their daily life. The degree of metamorphopsia was determined by M-CHARTS. The receiver operating characteristic curve was used to determine the best predictor of the changes in metamorphopsia in daily life. To determine the reproducibility of the M-CHARTS score, another set of 56 eyes with ERM was tested twice on two different days. The postoperative changes in the logarithm of the M-CHARTS score was defined as M2-value. The area under the receiver operating characteristic curve for the M2-value as a predictor of the changes in metamorphopsia in daily life was larger than area under the receiver operating characteristic curve obtained for any other parameter. The optimal cutoff value was -0.4. The 95% limits of agreement between test and retest measurements had a reproducibility of ±0.3 logarithm of the M-CHARTS score. Taking into account not only the reproducibility but also the consistency with the subjective changes, we determined the criterion for clinically significant changes in the M-CHARTS scores as a change of the M2-value by ≥0.4. Evaluating the changes in the M-CHARTS scores in logarithmic form is favorable not only theoretically but also from the perspective of consistency with the subjective changes.
    Preview · Article · Feb 2015 · Clinical Ophthalmology
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    ABSTRACT: To date, there has been only one published report on the infectious sclerokeratitis caused by Metarhizium anisopliae, which is an entomopathogenic fungus. Regarding corneal infection, three reports have been published to date. Although the prognoses of the corneal infections are favourable, prognosis when scleral infection is involved is very poor. A 76-year-old patient presented with foreign body sensation in the left eye. Microscopic examination with Fungi Flora Y staining of the corneal scraping revealed fungal infection. The conjunctiva was melted by the infection over a wide area. Although intensive medications were administered, an emergency surgery was necessary because scleral thinning, corneal perforation and lens prolapse occurred. The fungal isolate was identified as M. anisopliae by sequencing the internal transcribed spacer region. Herein, we report the second known case worldwide of M. anisopliae sclerokeratitis, and we review the literature related to the ocular infections. © 2015 Blackwell Verlag GmbH.
    No preview · Article · Jan 2015 · Mycoses
  • M. Egawa · K. Semba · T. Miyamoto · T. Naito · Y. Mitamura
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    ABSTRACT: Purpose: To report an unusual case of endogenous endophthalmitis due to Listeria mono-cytogens. Case: A 66-year-old female presented with hypopyon and severe uveitis in the left eye. She had been receiving peroral prednisolone, methotrexate and infliximab for rheumatoic arthritis. Smear of the aqueous humor showed gram-positive bacillus, leading to the diagnosis of infectious endophthalmitis. After treatment with antibiotics, vitrectomy was performed for dense vitreous opacity. Localized peripheral retinal vasculitis and exudates were observed during surgery. The visual acuity improved to 1.0. A strain of Listeria monocytogenes was isolated after cultivation of the aqueous. Conclusion: This case illustrates that Listeria monocytogenes may serve as pathogen for endophthalmitis when systemic immune suppression is present.
    No preview · Article · Dec 2014
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    ABSTRACT: In clinical settings, bacterial infections are usually diagnosed by isolation of colonies after laboratory cultivation followed by species identification with biochemical tests. However, biochemical tests result in misidentification due to similar phenotypes of closely related species. In such cases, 16S rDNA sequence analysis is useful. Herein, we report the first case of an Achromobacter-associated buckle infection that was diagnosed by 16S rDNA sequence analysis. This report highlights the significance of Achromobacter spp. in device-related ophthalmic infections. A 56-year-old woman, who had received buckling surgery using a silicone solid tire for retinal detachment eighteen years prior to this study, presented purulent eye discharge and conjunctival hyperemia in her right eye. Buckle infection was suspected and the buckle material was removed. Isolates from cultures of preoperative discharge and from deposits on the operatively removed buckle material were initially identified as Alcaligenes and Corynebacterium species. However, sequence analysis of a 16S rDNA clone library using the DNA extracted from the deposits on the buckle material demonstrated that all of the 16S rDNA sequences most closely matched those of Achromobacter spp. We concluded that the initial misdiagnosis of this case as an Alcaligenes buckle infection was due to the unreliability of the biochemical test in discriminating Achromobacter and Alcaligenes species due to their close taxonomic positions and similar phenotypes. Corynebacterium species were found to be contaminants from the ocular surface. Achromobacter spp. should be recognized as causative agents for device-related ophthalmic infections. Molecular species identification by 16S rDNA sequence analysis should be combined with conventional cultivation techniques to investigate the significance of Achromobacter spp. in ophthalmic infections.
    Preview · Article · Nov 2014 · BMC Ophthalmology
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    ABSTRACT: To determine whether peroxisome proliferator-activated receptor gamma (PPARγ), which is recognized as a component of the exosomes circulating in plasma, is expressed intraocularly in patients with proliferative diabetic retinopathy (PDR). The concentrations of PPARγ and vascular endothelial growth factor (VEGF) in the aqueous humor and vitreous of 50 eyes with PDR and 38 control eyes were determined by ELISA. The levels of the mRNA and protein of PPARγ were determined in proliferative membranes from 12 PDR and 5 control eyes by quantitative RT-PCR and immunohistochemical analyses. PPARγ was detected in the culture media of human umbilical vein endothelial cells indicating that PPARγ can be released into the extracellular fluid. The PPARγ concentrations in the aqueous humor and vitreous fluid were significantly higher in PDR patients than in controls (P<0.0005). There was a significant positive correlation between the PPARγ and VEGF concentrations (P<0.0005). The level of PPARγ increased as the clinical stage advanced. The expressions of the mRNA and protein of PPARγ were higher in the membranes of PDR than those of controls. Anti-VEGF therapy significantly reduced the VEGF concentration (P<0.0001) but not the PPARγ concentration. PPARγ may play an important role in the pathogenesis of PDR. Copyright © 2014 Elsevier Inc. All rights reserved.
    No preview · Article · Oct 2014 · Journal of Diabetes and its Complications
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    ABSTRACT: Aims To study the relationship between the retinal microstructures and the best-corrected visual acuity (BCVA) after cataract surgery in patients with retinitis pigmentosa (RP). Methods 58 eyes of 43 consecutive RP patients who underwent cataract surgery were studied. The BCVA was measured before and 3 months after the surgery. The appearance of the inner segment/outer segment (IS/OS) line of the photoreceptors in the optical coherence tomographic (OCT) images at the fovea was graded; Grade 1, IS/OS line not visible; Grade 2, IS/OS line abnormal or discontinuous; and Grade 3, IS/OS line normal. The central foveal thickness (CFT) and the length of the IS/OS line were measured in the spectral-domain OCT images. Results The postoperative BCVAs in logMAR units (Grade 1, 1.04±0.36; Grade 2, 0.33±0.16; Grade 3, 0.08±0.14) and the improvements in the BCVA in logMAR units (Grade 1, 0.22±0.28; Grade 2, 0.53±0.48; Grade 3, 0.54±0.35) were significantly different among Grade 1, 2 and 3 groups (p<0.0001, p=0.0378; respectively). A postoperative BCVA of <0.2 logMAR units was achieved in 0% in Grade 1, 20% in Grade 2 and 74% in Grade 3 (p<0.0001). There was a significant correlation between the postoperative BCVA and the length of the IS/OS line (r=−0.601 p<0.0001) or the CFT (r=−0.510, p<0.0001). Conclusions The presence of normal IS/OS line in the OCT images is associated with good visual recovery after cataract surgery in RP patients. The integrity of the IS/OS line may be important for predicting good postoperative BCVA.
    No preview · Article · Oct 2014 · British Journal of Ophthalmology
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    ABSTRACT: We present a case of prepapillary vascular loops complicated by a suspected macroaneurysm rupture which was treated with intravitreal bevacizumab (IVB). A 62-year-old woman presented with decreased vision and myodesopsia in her left eye. Her best-corrected visual acuity (BCVA) was 0.6 in the left eye. Fundus examination disclosed an elevated, round, and reddish lesion, retinal hemorrhage at the superior aspect of the optic disc, retinal opacification along the superior branch retinal artery, and a small vitreous hemorrhage. Optical coherence tomography showed a serous retinal detachment, and indocyanine green angiography demonstrated prepapillary vascular loops and a hypofluorescent area with hyperfluorescent margins. These findings suggested the presence of a macroaneurysm. No filling of the dye in the aneurysm-like dilatation suggested a blockage of the lumen with a thrombus which might be associated with a branch retinal artery occlusion (BRAO). A diagnosis of prepapillary vascular loops complicated by a suspected macroaneurysm rupture and BRAO was made. Because of a persistent serous retinal detachment, IVB was performed. One month later, the BCVA improved to 1.0. Fundus examination disclosed an organized yellowish-white macroaneurysm and resolution of the serous retinal detachment. We recommend careful monitoring of patients with prepapillary vascular loops because of complications such as macroaneurysm rupture and BRAO.
    Full-text · Article · Sep 2014
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    ABSTRACT: The dedicator of cytokinesis 3 (Dock3) is an atypical guanine nucleotide exchange factor that is predominantly expressed in the CNS. Dock3 exerts neuroprotective effects and stimulates optic nerve regeneration. The p38 mitogen-activated protein kinase acts downstream of apoptosis signal-regulating kinase 1 (ASK1) signaling and plays an important role in neural cell death. We assessed a therapeutic efficacy of Dock3 stimulation and p38 inhibition in retinal degeneration induced by optic nerve injury (ONI). In vivo retinal imaging using optical coherence tomography revealed that ONI-induced retinal degeneration was ameliorated in SB203580 (a p38 inhibitor)-treated WT mice and PBS-treated Dock3 overexpressing (Dock3 Tg) mice, and SB203580 further stimulated retinal protection in Dock3 Tg mice. In addition, SB203580 increased the number of regenerating axons after ONI in both WT and Dock3 Tg mice. ONI-induced phosphorylation of ASK1, p38 and the N-methyl-d-aspartate receptor 2B subunit were suppressed in the retina of Dock3 Tg mice. Inhibition of the ASK1 pathway in Dock3 Tg mice suggests that Dock3 may have an antioxidant-like property. These results indicate that overexpression of Dock3 and pharmacological interruption of p38 have synergistic effects for both neuroprotection and axon regeneration, thus combined application may be beneficial for the treatment of ONI.
    Full-text · Article · Aug 2014 · Neuroscience Letters
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    K Semba · K Namekata · A Kimura · C Harada · Y Mitamura · T Harada
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    ABSTRACT: Glaucoma is one of the leading causes of irreversible blindness that is characterized by progressive degeneration of optic nerves and retinal ganglion cells (RGCs). In the mammalian retina, excitatory amino-acid carrier 1 (EAAC1) is expressed in neural cells, including RGCs, and the loss of EAAC1 leads to RGC degeneration without elevated intraocular pressure (IOP). Brimonidine (BMD) is an α2-adrenergic receptor agonist and it is commonly used in a form of eye drops to lower IOP in glaucoma patients. Recent studies have suggested that BMD has direct protective effects on RGCs involving IOP-independent mechanisms, but it is still controversial. In the present study, we examined the effects of BMD in EAAC1-deficient (KO) mice, an animal model of normal tension glaucoma. BMD caused a small decrease in IOP, but sequential in vivo retinal imaging and electrophysiological analysis revealed that treatment with BMD was highly effective for RGC protection in EAAC1 KO mice. BMD suppressed the phosphorylation of the N-methyl-D-aspartate receptor 2B (NR2B) subunit in RGCs in EAAC1 KO mice. Furthermore, in cultured Müller glia, BMD stimulated the production of several neurotrophic factors that enhance RGC survival. These results suggest that, in addition to lowering IOP, BMD prevents glaucomatous retinal degeneration by stimulating multiple pathways including glia-neuron interactions.
    Full-text · Article · Jul 2014 · Cell Death & Disease

Publication Stats

2k Citations
291.32 Total Impact Points

Institutions

  • 2010-2015
    • The University of Tokushima
      • Department of Ophthalmology
      Tokusima, Tokushima, Japan
  • 2012
    • National Center for Global Health and Medicine in Japan
      Japan
  • 2007-2010
    • Chiba University
      • Department of Ophthalmology and Visual Science
      Tiba, Chiba, Japan
  • 2001-2007
    • Sapporo Medical University
      • Division of Ophthalmology
      Sapporo, Hokkaidō, Japan
  • 2000-2003
    • Toho University
      • Department of Ophthalmology
      Edo, Tōkyō, Japan