Publications by authors named "Yoko Ozawa"

144 Publications

ADIPOR1 deficiency-induced suppression of retinal ELOVL2 and docosahexaenoic acid levels during photoreceptor degeneration and visual loss.

Cell Death Dis 2021 May 7;12(5):458. Epub 2021 May 7.

Laboratory of Retinal Cell Biology, Tokyo, Japan.

Lipid metabolism-related gene mutations can cause retinitis pigmentosa, a currently untreatable blinding disease resulting from progressive neurodegeneration of the retina. Here, we demonstrated the influence of adiponectin receptor 1 (ADIPOR1) deficiency in retinal neurodegeneration using Adipor1 knockout (KO) mice. Adipor1 mRNA was observed to be expressed in photoreceptors, predominately within the photoreceptor inner segment (PIS), and increased after birth during the development of the photoreceptor outer segments (POSs) where photons are received by the visual pigment, rhodopsin. At 3 weeks of age, visual function impairment, specifically photoreceptor dysfunction, as recorded by electroretinography (ERG), was evident in homozygous, but not heterozygous, Adipor1 KO mice. However, although photoreceptor loss was evident at 3 weeks of age and progressed until 10 weeks, the level of visual dysfunction was already substantial by 3 weeks, after which it was retained until 10 weeks of age. The rhodopsin mRNA levels had already decreased at 3 weeks, suggesting that reduced rhodopsin may have contributed to early visual loss. Moreover, inflammation and oxidative stress were induced in homozygous KO retinas. Prior to observation of photoreceptor loss via optical microscopy, electron microscopy revealed that POSs were present; however, they were misaligned and their lipid composition, including docosahexaenoic acid (DHA), which is critical in forming POSs, was impaired in the retina. Importantly, the expression of Elovl2, an elongase of very long chain fatty acids expressed in the PIS, was significantly reduced, and lipogenic genes, which are induced under conditions of reduced endogenous DHA synthesis, were increased in homozygous KO mice. The causal relationship between ADIPOR1 deficiency and Elovl2 repression, together with upregulation of lipogenic genes, was confirmed in vitro. Therefore, ADIPOR1 in the retina appears to be indispensable for ELOVL2 induction, which is likely required to supply sufficient DHA for appropriate photoreceptor function and survival.
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http://dx.doi.org/10.1038/s41419-021-03741-5DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8105316PMC
May 2021

Myopia, corneal endothelial cell density and morphology in a Japanese population-based cross-sectional study: the JPHC-NEXT Eye Study.

Sci Rep 2021 Mar 18;11(1):6366. Epub 2021 Mar 18.

Department of Public Health, Graduate School of Medicine, Osaka University, Suita, Japan.

This population-based cross-sectional study was performed to determine the mean corneal endothelial cell density (ECD), coefficient of variation (CV), and hexagonality (HEX), and their associations with myopia in Japanese adults living in Chikusei city. Of 7109 participants with available data, 5713 (2331 male and 3382 female) participants were eligible for analysis. After assessing the relationship between participant characteristics and spherical equivalent refraction (SER), the association of SER with the abnormal value of ECD (< 2000 cells/mm), CV (≥ 0.40), and HEX (≤ 50%) were determined using the logistic regression models adjusting for potential confounders (age, intraocular pressure, keratometric power, height, and antihypertensive drug use). In male participants, there was no statistically significant relationships between SER and endothelial parameters. In female participants, compared to emmetropia, SER ≤ - 6 D had significantly higher odds ratio (OR) of having the abnormal value of CV (OR = 2.07, 95% confidence interval [CI] 1.39-3.10) and HEX (OR = 2.04, 95% CI 1.29-3.23), adjusted for potential confounders, indicating that the high myopia was associated with the abnormal values of CV and HEX. Further adjustment for contact lenses wear partly attenuated these associations. Association between the SER and ECD was not detected.
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http://dx.doi.org/10.1038/s41598-021-85617-4DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7973534PMC
March 2021

Taurine rescues mitochondria-related metabolic impairments in the patient-derived induced pluripotent stem cells and epithelial-mesenchymal transition in the retinal pigment epithelium.

Redox Biol 2021 May 28;41:101921. Epub 2021 Feb 28.

Laboratory of Retinal Cell Biology, Department of Ophthalmology, Keio University School of Medicine, 35 Shinanomachi, Shinjukuku, Tokyo, 160-8582, Japan; Department of Ophthalmology, Keio University School of Medicine, 35 Shinanomachi, Shinjukuku, Tokyo, 160-8582, Japan; Department of Ophthalmology, St. Luke's International Hospital, 9-1 Akashi-cho, Chuo-ku, Tokyo, 104-8560, Japan; St. Luke's International University, 9-1 Akashi-cho, Chuo-ku, Tokyo, 104-8560, Japan. Electronic address:

Mitochondria participate in various metabolic pathways, and their dysregulation results in multiple disorders, including aging-related diseases. However, the metabolic changes and mechanisms of mitochondrial disorders are not fully understood. Here, we found that induced pluripotent stem cells (iPSCs) from a patient with mitochondrial myopathy, encephalopathy, lactic acidosis, and stroke-like episodes (MELAS) showed attenuated proliferation and survival when glycolysis was inhibited. These deficits were rescued by taurine administration. Metabolomic analyses showed that the ratio of the reduced (GSH) to oxidized glutathione (GSSG) was decreased; whereas the levels of cysteine, a substrate of GSH, and oxidative stress markers were upregulated in MELAS iPSCs. Taurine normalized these changes, suggesting that MELAS iPSCs were affected by the oxidative stress and taurine reduced its influence. We also analyzed the retinal pigment epithelium (RPE) differentiated from MELAS iPSCs by using a three-dimensional culture system and found that it showed epithelial mesenchymal transition (EMT), which was suppressed by taurine. Therefore, mitochondrial dysfunction caused metabolic changes, accumulation of oxidative stress that depleted GSH, and EMT in the RPE that could be involved in retinal pathogenesis. Because all these phenomena were sensitive to taurine treatment, we conclude that administration of taurine may be a potential new therapeutic approach for mitochondria-related retinal diseases.
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http://dx.doi.org/10.1016/j.redox.2021.101921DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7944050PMC
May 2021

Cytomegalovirus retinitis after allogeneic hematopoietic stem cell transplantation under cytomegalovirus antigenemia-guided active screening.

Bone Marrow Transplant 2020 Dec 12. Epub 2020 Dec 12.

Division of Hematology, Department of Medicine, Keio University School of Medicine, Tokyo, Japan.

Although cytomegalovirus (CMV) remains a leading cause of morbidity and mortality after allogeneic hematopoietic stem cell transplantation (HSCT), the incidence of CMV retinitis is considered to be lower than the incidence of CMV infection in other organs following allogeneic HSCT. In this study, the incidence and characteristics of CMV retinitis were retrospectively evaluated in recipients of allogeneic HSCT. Ophthalmological screening was performed at the development of ocular symptoms or positive CMV infection using peripheral blood evaluated by pp65 antigenemia or polymerase chain reaction. Of the 514 patients, 13 patients developed CMV retinitis. The median onset of CMV retinitis was day 34 (range, 21-118) post transplant, and the cumulative incidence was 2.5% (95% CI, 1.6-4.2) at 6 months after transplantation. Five patients presented ocular symptoms at the onset. In the remaining eight asymptomatic patients, the diagnosis of CMV retinitis was made by the screening guided by positive CMV infection. All evaluable patients responded to antiviral treatment but three showed incomplete improvement with ocular sequela. Our results suggest that the incidence of CMV retinitis after allogeneic HSCT is not negligible and active ophthalmological screening based not only on symptoms but also positive CMV infection monitoring contributes to the early diagnosis of CMV retinitis.
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http://dx.doi.org/10.1038/s41409-020-01176-8DOI Listing
December 2020

Renin-angiotensin system impairs macrophage lipid metabolism to promote age-related macular degeneration in mouse models.

Commun Biol 2020 Dec 9;3(1):767. Epub 2020 Dec 9.

Laboratory of Retinal Cell Biology, Department of Ophthalmology, Keio University School of Medicine, 35 Shinanomachi, Shinjukuku, Tokyo, 160-8582, Japan.

Metabolic syndrome, a condition involving obesity and hypertension, increases the risk of aging-associated diseases such as age-related macular degeneration (AMD). Here, we demonstrated that high-fat diet (HFD)-fed mice accumulated oxidized low-density lipoprotein (ox-LDL) in macrophages through the renin-angiotensin system (RAS). The ox-LDL-loaded macrophages were responsible for visual impairment in HFD mice along with a disorder of the retinal pigment epithelium (RPE), which is required for photoreceptor outer segment renewal. RAS repressed ELAVL1, which reduced PPARγ, impeding ABCA1 induction to levels that are sufficient to excrete overloaded cholesterol within the macrophages. The ox-LDL-loaded macrophages expressed inflammatory cytokines and attacked the RPE. An antihypertensive drug, angiotensin II type 1 receptor (AT1R) blocker, resolved the decompensation of lipid metabolism in the macrophages and reversed the RPE condition and visual function in HFD mice. AT1R signaling could be a future therapeutic target for macrophage-associated aging diseases, such as AMD.
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http://dx.doi.org/10.1038/s42003-020-01483-2DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7725839PMC
December 2020

Oxidative stress in the light-exposed retina and its implication in age-related macular degeneration.

Authors:
Yoko Ozawa

Redox Biol 2020 10 2;37:101779. Epub 2020 Nov 2.

St Luke's International University, Department of Ophthalmology, St Luke's International Hospital, 9-1 Akashi-cho, Chuo-ku, Tokyo, 104-8560, Japan; Laboratory of Retinal Cell Biology, Department of Ophthalmology, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo, 160-8582, Japan. Electronic address:

The retina continuously receives light to enable vision, and the related processes require a marked amount of energy. During active metabolism, reactive oxygen species (ROS) are generated in exchange. Although physiologically generated ROS may be removed by endogenous antioxidant systems, and the effects of oxidative stress may be recovered by repair systems to retain homeostasis and health, when ROS and oxidative stress exceed the capacity of the antioxidant and repair systems, the condition becomes pathological. Multiple mechanisms of oxidative stress and the effects of antioxidant and repair systems in the retina have long been analyzed using light-induced retinal degeneration models. Among the mechanisms, a positive feedback loop of oxidative stress and related inflammation may be involved in the pathogenesis of a blinding aging disease, age-related macular degeneration. Treatments for suppressing ROS and oxidative stress by administrating antioxidant products may support the tissue-protective function of antioxidant systems. Moreover, recent studies have proposed a new concept for maintaining homeostasis by supplying sufficient energy to activate the repair systems. The current review will help elucidate the influence of oxidative stress and guide future analyses to explore new therapeutic approaches for oxidative stress-mediated diseases.
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http://dx.doi.org/10.1016/j.redox.2020.101779DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7767731PMC
October 2020

Association between axial length and choroidal thickness in early age-related macular degeneration.

PLoS One 2020 9;15(10):e0240357. Epub 2020 Oct 9.

Department of Ophthalmology, Keio University School of Medicine, Tokyo, Japan.

The clinical course of age-related macular degeneration (AMD) is related to choroidal conditions, and can be determined by the evaluation of the central choroidal thickness (CCT). The aim of this study was to determine the association between the axial length (AL) and choroidal thickness in AMD by measuring these parameters in patients with and without AMD. Seventy eyes of 70 patients (34 men and 36 women; age, 64-88 years; mean age, 77.0 ± 6.5 years) who underwent cataract surgery from February 2015 to March 2020 at the Department of Ophthalmology, Keio University School of Medicine were retrospectively analyzed. The AMD group (29 patients, 29 eyes) included eyes with early AMD, whereas the control group (41 patients, 41 eyes) included those without ocular diseases other than cataract. Optical coherence tomography images were used to measure the CCT and the choroidal vessel diameter (CVD). The IOL Master was used to measure the AL. The results revealed that mean CCT was greater in the AMD group (238.3 ± 108.3 μm) compared with the age-matched control group (187.2 ± 66.8 μm) (p = 0.03). The CCT was negatively correlated with AL in the overall sample (r = -0.42, p = 0.001), the AMD group (r = -0.42, p = 0.02), and the control group (r = -0.42, p = 0.006). Note that all eyes with CCT > 350 μm were included in the AMD group. CCT and CVD were positively correlated in the overall sample (r = 0.76, p < 0.001) as well as in the individual groups (AMD: r = 0.82, p < 0.001; control: r = 0.76, p = 0.004). Given that CCT is an important parameter for predicting the prognosis of subfoveal diseases, routine evaluation of AL may be valuable for a better understanding of the pathogenesis of AMD.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0240357PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7546466PMC
December 2020

Risk of newly developing visual field defect and neurodegeneration after pars plana vitrectomy for idiopathic epiretinal membrane.

Br J Ophthalmol 2020 Oct 5. Epub 2020 Oct 5.

Department of Ophthalmology, Keio University School of Medicine, Shinjuku-ku, Tokyo, Japan

Background/aims: Pars plana vitrectomy (PPV) is widely performed in patients with idiopathic epiretinal membrane (iERM) to improve vision. Postoperative visual field defects (VFDs) have been previously reported. However, whether they occur when using the most recent PPV system, and the frequency of VFDs as measured by standard automated perimetry, remain poorly documented and were examined in this study.

Methods: Data of 30 eyes (30 patients; mean age, 66.1 years; 15 men) who underwent PPV for iERM during February 2016-June 2019 and had preoperative and postoperative visual field measurements using standard automated perimetry (Humphrey visual field analyser 30-2 program) were retrospectively analysed. Eyes with diseases other than iERM, including moderate-to-severe cataract or preoperative VFDs were excluded.

Results: VFD, defined by the Anderson and Patella's criteria, was found in 73.3% of the eyes 1 month after PPV. After age adjustment, internal limiting membrane (ILM) peeling was identified as a risk factor for postoperative VFD (p=0.035; 95% CI 1.173 to 92.8). Postoperative VFD was frequently observed nasally (86.4%, p=0.002), and on optical coherence tomography measurements, ganglion cell layer (GCL) thinning was found temporal to the fovea (p=0.008). Thinning of the superior and inferior retinal nerve fibre layers and of the GCL temporal to the fovea were significant in eyes after ILM peeling (all p<0.05).

Conclusion: ILM peeling may cause inner retinal degeneration and lead to the development of VFDs after PPV, which should be further examined.
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http://dx.doi.org/10.1136/bjophthalmol-2020-317478DOI Listing
October 2020

Hyperreflective Material in Optical Coherence Tomography Images of Eyes with Myopic Choroidal Neovascularization May Affect the Visual Outcome.

J Clin Med 2020 Jul 27;9(8). Epub 2020 Jul 27.

Department of Ophthalmology, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582, Japan.

The visual outcome of myopic choroidal neovascularization (CNV) after anti-vascular endothelial growth factor (anti-VEGF) therapy varies among individuals. We retrospectively analyzed the data of 24 eyes (24 patients) with treatment-naïve myopic CNV who underwent anti-VEGF monotherapy following a pro-re-nata regimen at the Division of Medical Retina Clinic, Department of Ophthalmology, Keio University Hospital between May 2014 and December 2017. The mean age was 70.6 ± 2.1 years, and 16 (66.7%) patients were female. Overall, the mean best-corrected visual acuity (BCVA) improved ( = 0.034), and the mean height of the hyperreflective material (HRM), involving the CNV lesion recorded by optical coherence tomography, decreased ( < 0.01) 12 months after the initial treatment. Fifteen eyes (62.5%) achieved a BCVA of better than 0.10 in LogMAR at 12 months; they had a better BCVA ( = 0.015) and lower HRM intensity ( = 0.033) at baseline than the others. Remarkably, the BCVA improved ( < 0.05) and the HRM height ( < 0.01) decreased only in eyes with a final BCVA better than 0.10 as early as 1 month after the initial treatment, which was still present at 12 months. The HRM height and intensity, not only the BCVA, would be valuable in evaluating the prognosis of myopic CNV after anti-VEGF therapy, although further study is required.
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http://dx.doi.org/10.3390/jcm9082394DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7466026PMC
July 2020

Ocular and Systemic Effects of Antioxidative Supplement Use in Young and Healthy Adults: Real-World Cross-Sectional Data.

Antioxidants (Basel) 2020 Jun 3;9(6). Epub 2020 Jun 3.

Department of Ophthalmology, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582, Japan.

Randomized controlled studies have shown that antioxidative supplements are effective in suppressing the progression of age-related macular degeneration and visual display terminal syndrome. However, effects of their general use in the real-world and by young and healthy individuals have not been well documented. We analyzed 27 participants who were under 35 years of age and had no diagnosed diseases. Mean functional visual acuity (FVA) score and visual maintenance ratio, which represent quick recognition of a target, both measured using FVA system, were better (both < 0.01) in subjects who had had regular antioxidative supplement intake for more than 2 months (11 participants) compared with those who had not. Systemic data, i.e., total cholesterol, hemoglobin A1c (HbA1c), and high-sensitivity C-reactive protein (hs-CRP) levels, which correspond to chronic low-grade inflammation, were lower (all < 0.05) in the former. Overall, hs-CRP levels had a correlation with total cholesterol ( < 0.05) and a trend of correlation with HbA1c ( = 0.054) levels. Thus, current real-world data showed that young, healthy participants who had a regular intake of antioxidative supplements had better visual acuity and systemic levels of metabolic and low-grade inflammation markers. This study will help promote future research into the effects of general antioxidative supplement use.
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http://dx.doi.org/10.3390/antiox9060487DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7346213PMC
June 2020

The Area and Number of Intraretinal Cystoid Spaces Predict the Visual Outcome after Ranibizumab Monotherapy in Diabetic Macular Edema.

J Clin Med 2020 May 8;9(5). Epub 2020 May 8.

Laboratory of Retinal Cell Biology, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582, Japan.

Visual outcomes in diabetic macular edema (DME) after anti-vascular endothelial growth factor therapy vary across individuals. We retrospectively reviewed the clinical records for 46 treatment-naive eyes of 46 patients with DME who underwent intravitreal ranibizumab (IVR) monotherapy with a pro re nata regimen for 12 months. Overall, mean best-corrected visual acuity (BCVA) improved. Multivariate analyses adjusted for age and baseline BCVA showed that the area ratio, compared with the retinal area, and the number of intraretinal cystoid spaces evaluated on OCT (optical coherence tomography) images at baseline positively correlated with LogMAR BCVA and the extents of ellipsoid zone and external limiting membrane disruption at 12 months, and negatively correlated with central retinal thickness at the time of edema resolution. Therefore, a high area ratio and large number of intraretinal cystoid spaces resulted in a disorganized outer retinal structure at 12 months, a thin and atrophic retina after edema resolution, and a worse visual outcome. The area ratio and number of intraretinal cystoid spaces on initial OCT images were predictors of the visual outcome after IVR therapy in DME irrespective of baseline age and BCVA. The factors were related to retinal neurodegenerative changes in DME and could help in obtaining proper informed consent before treatment.
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http://dx.doi.org/10.3390/jcm9051391DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7290842PMC
May 2020

Macular Pigment Optical Density and Photoreceptor Outer Segment Length as Predisease Biomarkers for Age-Related Macular Degeneration.

J Clin Med 2020 May 5;9(5). Epub 2020 May 5.

Laboratory of Retinal Cell Biology, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582, Japan.

To explore predisease biomarkers, which may help screen for the risk of age-related macular degeneration (AMD) at very early stages, macular pigment optical density (MPOD) and photoreceptor outer segment (PROS) length were analyzed. Thirty late AMD fellow eyes, which are at high risk and represent the predisease condition of AMD, were evaluated and compared with 30 age-matched control eyes without retinal diseases; there was no early AMD involvement in the AMD fellow eyes. MPOD was measured using MPS2 (M.E. Technica Co. Ltd., Tokyo, Japan), and PROS length was measured based on optical coherence tomography images. MPOD levels and PROS length in the AMD fellow eyes were significantly lower and shorter, respectively, than in control eyes. MPOD and PROS length were positively correlated in control eyes (R = 0.386; = 0.035) but not in AMD fellow eyes. Twenty (67%) AMD fellow eyes met the criteria of MPOD < 0.65 and/or PROS length < 35 μm, while only five (17%) control eyes did. After adjusting for age and sex, AMD fellow eyes more frequently satisfied the definition ( < 0.001; 95% confidence interval, 3.50-60.4; odds ratio, 14.6). The combination of MPOD and PROS length may be a useful biomarker for screening predisease AMD patients, although further studies are required in this regard.
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http://dx.doi.org/10.3390/jcm9051347DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7290696PMC
May 2020

A comparison of the features of fluorine-18 fluorodeoxyglucose-positron emission tomography (FDG-PET) between IgG4-related disease with bilateral hilar lymphadenopathy and sarcoidosis.

Nagoya J Med Sci 2020 Feb;82(1):101-111

First Department of Internal Medicine, Shinshu University School of Medicine, Matsumoto, Nagano, Japan.

We aimed to show the differentiation of the degree and distribution on Fluorine-18 fluorodeoxyglucose-positron emission tomography (FDG-PET) between patients with immunoglobulin G4-related disease (IgG4-RD) and sarcoidosis, though both diseases frequently show bilateral hilar lymphadenopathy (BHL). The clinical records were retrospectively reviewed in 25 patients with IgG4-RD with BHL and 15 patients with sarcoidosis (stage I-II) diagnosed at Shinshu University Hospital. All patients underwent FDG-PET at Aizawa Hospital from January 2004 to December 2015. The FDG accumulation pattern and maximum standardized uptake value (SUVmax) of the hilar lymph nodes were compared between the two groups. The IgG4-RD group (21 men; median age 69 years) showed a significant male predominance and older age compared with the sarcoidosis group (3 men, median age 55.4 years). The IgG4-RD group showed a significantly higher incidence of FDG accumulation in the lachrymal gland, submandibular gland, pancreas, prostate and periurethral and periarterial regions compared with the sarcoidosis group. In contrast, the sarcoidosis group showed a significantly higher incidence of FDG accumulation in the supraclavicular and abdominal lymph nodes, muscle and soft tissues compared with the IgG4-RD group. Furthermore, the SUVmax of the hilar lymph nodes was significantly higher in the sarcoidosis group (median 7.20) than in the IgG4-RD group (median 4.20, p=0.002). In conclusion, significant differences were observed in the FDG accumulation patterns and SUVmax values of the hilar lymph nodes between IgG4-RD with BHL and sarcoidosis, although both diseases develop through the lymphatic routes of the lungs and are frequently associated with BHL.
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http://dx.doi.org/10.18999/nagjms.82.1.101DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7103870PMC
February 2020

Correlation between Macular Pigment Optical Density and Neural Thickness and Volume of the Retina.

Nutrients 2020 Mar 25;12(4). Epub 2020 Mar 25.

Laboratory of Retinal Cell Biology, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582, Japan.

Macular pigment (MP), which is composed of lutein/zeaxanthin/mezo-zeaxanthin, is concentrated in the central part of the retina, the macula. It protects the macula by absorbing short-wavelength light and suppressing oxidative stress. To evaluate whether MP levels are related to retinal neural protection and resulting health, we analyzed the association between the MP optical density (MPOD), and the macular thickness and volumes. Forty-three eyes of 43 healthy adult volunteers (21 men and 22 women; age: 22-48 (average 31.4 ± 1.1) years) were analyzed. Highly myopic eyes (<-6 diopters) were excluded. MPOD was measured using MPS2®, and the neural retinal thickness and volume were measured using optical coherence tomography. The mean MPOD was 0.589 ± 0.024, and it positively correlated with the central retinal thickness ( = 0.017, R = 0.360) and retinal volume of the fovea (1-mm diameter around the fovea; = 0.029, R = 0.332), parafovea (1-3-mm diameter; = 0.002, R = 0.458), and macula (6-mm diameter; = 0.003, R = 0.447). In the macular area (diameter: 6 mm), MPOD was correlated with the retinal neural volume of the ganglion cell layer ( = 0.037, R = 0.320), inner plexiform layer ( = 0.029, R = 0.333), and outer nuclear layer ( = 0.020, R = 0.353). Thus, MPOD may help in estimating neural health. Further studies should determine the impact of MP levels on neuroprotection.
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http://dx.doi.org/10.3390/nu12040888DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7230595PMC
March 2020

Relationships of diabetes and hyperglycaemia with intraocular pressure in a Japanese population: the JPHC-NEXT Eye Study.

Sci Rep 2020 03 24;10(1):5355. Epub 2020 Mar 24.

Epidemiology and Prevention Group, Centre for Public Health Sciences, National Cancer Centre, 5-1-1 Tsukiji, Chuo-ku, Tokyo, 104-0045, Japan.

Although a meta-analysis previously suggested a positive relationship between diabetes and intraocular pressure (IOP), the interrelationships among diabetes, IOP, and other ocular biometric parameters remain unclear. The present study investigated the relationships of diabetes, haemoglobin A1c (HbA1c), and serum glucose with IOP and ocular hypertension (IOP > 21 mmHg) in non-glaucomatous Japanese adults living in Chikusei City. Diabetes was defined as a self-reported history of diabetes, the use of antidiabetic medication, or HbA1c levels ≥6.5%. Among 6,786 enrolled participants aged 40 years and above, 734 were classified as diabetic (10.8%). After adjusting for several confounders, the IOP values were significantly higher in participants with diabetes than in those without diabetes (14.4 ± 0.1 vs. 13.9 ± 0.1 mmHg, P < 0.001) and were also significantly increased in those with elevated HbA1c and serum glucose levels (both P < 0.001). Moreover, diabetes was significantly related to ocular hypertension (multivariable-adjusted odds ratio, 1.75; 95% confidence interval, 1.09-2.81; P < 0.05). The positive influence of diabetes with ocular hypertension was consistent even after adjustment for central corneal thickness. In conclusion, diabetes, elevated HbA1c, and increased serum glucose are significant contributing factors for elevated IOP.
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http://dx.doi.org/10.1038/s41598-020-62135-3DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7093393PMC
March 2020

Neuroprotective and vision-protective effect of preserving ATP levels by AMPK activator.

FASEB J 2020 04 24;34(4):5016-5026. Epub 2020 Feb 24.

Department of Ophthalmology, Keio University School of Medicine, Tokyo, Japan.

Progression of blinding diseases, such as age-related macular degeneration, is accelerated by light exposure. However, no particular intervention is applied to the photostress. Here, we report neuroprotective effects of the adenosine monophosphate (AMP)-activated protein kinase (AMPK) activator, 5-Aminoimidazole-4-carboxamide ribonucleotide (AICAR), on light-induced visual function impairment, photoreceptor disorders and death in mice. Increase in retinal ATP levels in response to photostress was transient, because oxygen consumption rate (OCR) and cytochrome c oxidase (CcO) activity were reduced under photostress. However, AICAR treatment preserved OCR, CcO activity, and high levels of retinal ATP after light exposure. AMPK knockdown in the photoreceptor-derived cell line revealed that AMPK targeted CcO activity. Further, our data indicated that photostress reduced mitochondrial respiratory function and ATP levels, while AICAR treatment promoted neuronal survival and retained visual function, stabilizing ATP levels through preserved CcO activity. The current study has provided proof of concept for providing cells with sufficient energy to promote cell survival in the presence of cellular stress. This is in contrast to the previous reports which primarily investigated therapeutic approaches to suppress stress signals. Hence, stabilization of the ATP supply may serve as a novel therapeutic approach to support tissue survival under stress and prevent neurodegeneration.
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http://dx.doi.org/10.1096/fj.201902387RRDOI Listing
April 2020

n-3 Fatty Acid and Its Metabolite 18-HEPE Ameliorate Retinal Neuronal Cell Dysfunction by Enhancing Müller BDNF in Diabetic Retinopathy.

Diabetes 2020 04 5;69(4):724-735. Epub 2020 Feb 5.

Department of Ophthalmology, Nagoya University Graduate School of Medicine, Nagoya, Japan.

Diabetic retinopathy (DR) is a widespread vision-threatening disease, and neuroretinal abnormality should be considered as an important problem. Brain-derived neurotrophic factor (BDNF) has recently been considered as a possible treatment to prevent DR-induced neuroretinal damage, but how BDNF is upregulated in DR remains unclear. We found an increase in hydrogen peroxide (HO) in the vitreous of patients with DR. We confirmed that human retinal endothelial cells secreted HO by high glucose, and HO reduced cell viability of MIO-M1, Müller glia cell line, PC12D, and the neuronal cell line and lowered BDNF expression in MIO-M1, whereas BDNF administration recovered PC12D cell viability. Streptozocin-induced diabetic rats showed reduced BDNF, which is mainly expressed in the Müller glia cell. Oral intake of eicosapentaenoic acid ethyl ester (EPA-E) ameliorated BDNF reduction and oscillatory potentials (OPs) in electroretinography (ERG) in DR. Mass spectrometry revealed an increase in several EPA metabolites in the eyes of EPA-E-fed rats. In particular, an EPA metabolite, 18-hydroxyeicosapentaenoic acid (18-HEPE), induced BDNF upregulation in Müller glia cells and recovery of OPs in ERG. Our results indicated diabetes-induced oxidative stress attenuates neuroretinal function, but oral EPA-E intake prevents retinal neurodegeneration via BDNF in Müller glia cells by increasing 18-HEPE in the early stages of DR.
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http://dx.doi.org/10.2337/db19-0550DOI Listing
April 2020

Relationship between nerve fiber layer defect and the presence of epiretinal membrane in a Japanese population: The JPHC-NEXT Eye Study.

Sci Rep 2020 01 21;10(1):779. Epub 2020 Jan 21.

Department of Public Health Medicine, Faculty of Medicine, and Health Services Research and Development Center, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, 305-8575, Japan.

The study subjects were residents of Chikusei city, Japan, aged 40 years or older who attended annual health check-up programs and participated in the JPHC-NEXT Eye Study which performed non-mydriatic fundus photography of both eyes. The relationship of glaucomatous fundus changes such as optic disc cupping (cup to disc ratio ≥ 0.7) and retinal nerve fiber layer defect (NFLD) with the presence of epiretinal membrane (ERM) were examined cross-sectionally. A total of 1990 persons gave consent to participate in this study in 2013. The overall prevalence of ERM was 12.9%. Of these, 1755 had fundus photographs of sufficient quality and no history of intraocular surgery (mean age: 62.3 ± 10.0 years). After adjusting for age, sex and refractive error, NFLD was positively associated with the presence of ERM (odds ratio [OR]: 2.48; 95% confidence interval [CI]: 1.24, 4.96; P = 0.010), but optic disc cupping was not (OR: 1.33; CI: 0.71, 2.48; P = 0.37). The results did not necessarily suggest an association between glaucoma and ERM, but indicated an association between NFLD and ERM.
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http://dx.doi.org/10.1038/s41598-019-57260-7DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6972763PMC
January 2020

Effect of axial length and age on the visual outcome of patients with idiopathic epiretinal membrane after pars plana vitrectomy.

Sci Rep 2019 12 13;9(1):19056. Epub 2019 Dec 13.

Department of Ophthalmology, Keio University School of Medicine, Tokyo, Japan.

We evaluated predictive factors for visual outcomes in patients with idiopathic epiretinal membrane (iERM) after pars plana vitrectomy (PPV). Clinical records for 114 eyes (114 patients, mean age: 70.6 years) with iERM treated by PPV between March 2012 and March 2018 were retrospectively reviewed. Overall, the mean postoperative best-corrected visual acuity (BCVA) and central retinal thickness measured by optical coherence tomography improved as early as 1 month after surgery, and further improved until 3 months (P < 0.01). Multiple linear regression analyses adjusted for the preoperative BCVA showed that older age (B, 0.010; 95% confidence interval, 0.003 to 0.016; P = 0.003) and a shorter axial length (AL; B, -0.059; 95% confidence interval, -0.099 to -0.019; P = 0.005) predicted worse postoperative BCVA. The Mann-Whitney U test showed that the postoperative BCVA was worse in eyes with AL < 23.6 mm than in eyes with AL ≥ 23.6 mm (P = 0.037), and in patients aged ≥69 years than in patients aged <69 years (P = 0.024). The findings may help in evaluating surgical indications for each patient to obtain satisfactory outcomes, irrespective of the preoperative BCVA.
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http://dx.doi.org/10.1038/s41598-019-55544-6DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6911110PMC
December 2019

Dynamic changes in neural retinal images during the development of a lamellar macular hole: A case report.

Medicine (Baltimore) 2019 Dec;98(49):e18297

Department of Ophthalmology, Keio University, School of Medicine, Shinjukuku, Tokyo, Japan.

Rationale: Lamellar macular hole (LMH) comprises a partial-thickness defect of the macula, the central part of the neural retina. Classification of LMHs into degenerative and tractional types has been proposed based on macular morphology observed on optical coherence tomography (OCT) imaging. Although LMHs are assumed to develop from aborted full-thickness macular holes, the clinical course of LMH development is not fully understood.

Patient Concerns: A 67-year-old man noticed slight changes in his central vision, and exhibited gradual change in macular morphology.

Diagnosis: The patient was first diagnosed with macular hole, which closed spontaneously. He then developed an LMH.

Interventions: The patient was placed under observation.

Outcomes: The patient first exhibited a macular hole, which resolved spontaneously. However, the tractional force at the surface of the macula became more severe, thereby causing retinoschisis-like appearance, which is the characteristic finding of a tractional LMH. The same eye then developed a lamellar hole-associated epiretinal proliferation (LHEP)-like structure, which is often observed in a degenerative LMH; importantly, the retinoschisis-like appearance persisted. Finally, the macula formed a typical degenerative LMH, characterized by intraretinal cavitation with persistent LHEP and disappearance of the retinoschisis-like structure.

Lessons: The present report shows dynamic changes of neural retinal morphology during development of an LMH: a tractional LMH developed initially; it then transformed into a degenerative LMH, which comprises a neurodegenerative disease. The findings in this report may help to understand the pathogenesis of LMHs and to elucidate the neurodegenerative disease process in various fields.
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http://dx.doi.org/10.1097/MD.0000000000018297DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6919539PMC
December 2019

Spatial-sweep steady-state pattern electroretinography can detect subtle differences in visual function among healthy adults.

Sci Rep 2019 12 2;9(1):18119. Epub 2019 Dec 2.

Department of Ophthalmology, Keio University School of Medicine, Tokyo, Japan.

We aimed to establish a highly sensitive method for measuring visual function using spatial-sweep steady-state pattern electroretinography (swpPERG). Overall, 35 eyes of 35 healthy adults (18 men; mean age, 32.3 years) were examined using swpPERG, and the data were recorded using spatial-patterned and contrast-reversed stimuli of size 1 (thickest) to 6. Data were converted into frequency-domain using a Fourier transform and expressed by signal-to-noise ratio (SNR). The number of participants who showed SNR ≥ 1 was significantly lesser at stimulus sizes 5 and 6 compared with those at greater stimulus sizes. Among the data with SNR ≥ 1, SNRs were negatively correlated with age at stimulus size 5 (r = -0.500, P = 0.029), and positively correlated with macular volume evaluated by optical coherence tomography (OCT) within a 6-mm circle diameter from the fovea of the retinal nerve fibre layer at size 4 (r = 0.409, P = 0.025) and of the ganglion cell layer at size 5 (r = 0.567, P = 0.011). We found that SNRs of swpPERG, recorded using the EvokeDx system, were correlated with age and macular morphology in participants without diagnosed eye diseases. The system detected subtle differences in retinal function, which may help in early disease diagnosis and visual evaluation in neuroprotective interventions in the future.
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http://dx.doi.org/10.1038/s41598-019-54606-zDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6889279PMC
December 2019

Dietary Spirulina Supplementation Protects Visual Function From Photostress by Suppressing Retinal Neurodegeneration in Mice.

Transl Vis Sci Technol 2019 Nov 20;8(6):20. Epub 2019 Nov 20.

Laboratory of Retinal Cell Biology, Keio University School of Medicine, Tokyo, Japan.

Purpose: We investigated whether daily consumption of Spirulina, an antioxidant generating cyanobacterial nutritional supplement, would suppress photostress-induced retinal damage and prevent vision loss in mice.

Methods: Six-week-old male BALB/cAJcl mice were allowed constant access to either a standard or Spirulina-supplemented diet (20% Spirulina) that included the antioxidants, β-carotene and zeaxanthin, and proteins for 4 weeks. Following dark adaptation, mice were exposed to 3000-lux white light for 1 hour and returned to their cages. Visual function was analyzed by electroretinogram, and retinal histology by hematoxylin and eosin staining, terminal deoxynucleotidyl transferase-mediated, deoxyuridine triphosphate nick-end labeling (TUNEL) assay, and immunohistochemistry. Retinal expression of proteins, reactive oxygen species (ROS), and mRNAs were measured using immunoblot analysis, enzyme-linked immunosorbent assay (ELISA), 2',7'-dichlorofluorescein-diacetate, or ROS Brite 700 Dyes, and real-time reverse-transcription polymerase chain reaction, respectively.

Results: Light-induced visual function impairment was suppressed by constant Spirulina intake. Thinning of the photoreceptor layer and outer segments, photoreceptor cell death, decreased rhodopsin protein, and induction of glial fibrillary acidic protein were ameliorated in the Spirulina-intake group. Increased retinal ROS levels after light exposure were reduced by Spirulina supplementation. Light-induced superoxide dismutase 2 and heme oxygenase-1 mRNAs in the retina, and Nrf2 activation in the photoreceptor cells, were preserved with Spirulina supplementation, despite reduced ROS levels, suggesting two pathways for suppressing ROS, scavenging and induction of endogenous antioxidative enzymes. Light-induced MCP-1 retinal mRNA and proteins were also suppressed by Spirulina.

Conclusions: Spirulina ingestion protected retinal photoreceptors from photostress in the retina.

Translational Relevance: Spirulina has potential as a nutrient supplement to prevent vision loss related to oxidative damage in the future.
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http://dx.doi.org/10.1167/tvst.8.6.20DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6871545PMC
November 2019

Predicting recurrences of macular edema due to branch retinal vein occlusion during anti-vascular endothelial growth factor therapy.

Graefes Arch Clin Exp Ophthalmol 2020 Jan 15;258(1):49-56. Epub 2019 Nov 15.

Laboratory of Retinal Cell Biology, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo, 160-8582, Japan.

Purpose: To determine the predictive factors for recurrent macular edema due to branch retinal vein occlusion (BRVO) during intravitreal ranibizumab (IVR) monotherapy.

Methods: Clinical records were retrospectively reviewed for 65 patients (mean age 66.5 years, 65 eyes) who were diagnosed with macular edema due to BRVO and treated with IVR monotherapy for 12 months at the Medical Retina Division, Department of Ophthalmology, Keio University Hospital between October 2013 and August 2017. Best-corrected visual acuity (BCVA), fundus findings, and sectional optical coherence tomography (OCT) images were analyzed.

Results: Overall BCVA and central retinal thickness (CRT) improved (all p < 0.01). BCVA at 12 months was significantly worse in patients with recurrent macular edema (40 eyes [61.5%]) (p < 0.01) than in those without, while CRT decreased and was comparable in both groups at 12 months. Logistic regression analyses showed association of recurrence with disorganization of the retinal inner layer (DRIL) temporal to the fovea at baseline (odds ratio = 7.74; 95% confidence interval 1.62-37.08, p = 0.01), after adjusting for age, gender, and initial CRT.

Conclusion: Recurrent macular edema due to BRVO affects visual outcome and is associated with initial DRIL temporal to the fovea, evaluated using OCT sectional images before treatments. DRIL may facilitate determination of follow-up schedules in clinical practice.
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http://dx.doi.org/10.1007/s00417-019-04495-9DOI Listing
January 2020

High Myopia and Its Associated Factors in JPHC-NEXT Eye Study: A Cross-Sectional Observational Study.

J Clin Med 2019 Oct 25;8(11). Epub 2019 Oct 25.

Department of Ophthalmology, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582, Japan.

The increasing prevalence of high myopia has been noted. We investigated the epidemiological characteristics and the related factors of high myopia in a Japanese adult population. Japan Public Health Center-Based Prospective Study for the Next Generation (JPHC-NEXT) Eye Study was performed in Chikusei-city, a rural area in mid-east Japan, between 2013 and 2015. A cross-sectional observational analysis was conducted to investigate prevalence and related factors of high myopia. A total of 6101 participants aged ≥40 years without a history of ocular surgeries was included. High myopia was defined as a spherical equivalent refraction of ≤-6.00 diopters according to the American Academy of Ophthalmology. Potential high myopia-related factors included intraocular pressure (IOP), corneal structure, corneal endothelial cell density, age, height, body mass index, heart rate, blood pressure, biochemical profile, and current history of systemic and ocular disorders. The odds ratios of high myopia were estimated using the logistic regression models adjusted for the associated factors. The prevalence of high myopia was 3.8% in males and 5.9% in females with a significant difference. Age was inversely associated, IOP was positively associated, and none of other factors were associated with high myopia in both sexes. In conclusion, only age and IOP were associated with high myopia in this community-based sample.
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http://dx.doi.org/10.3390/jcm8111788DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6912595PMC
October 2019

Subclinical hypopigmentation of the skin and hair in a Japanese patient with Hermansky-Pudlak syndrome type 3.

J Dermatol 2020 Jan 16;47(1):e18-e20. Epub 2019 Oct 16.

Department of Dermatology, Keio University School of Medicine, Tokyo, Japan.

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http://dx.doi.org/10.1111/1346-8138.15118DOI Listing
January 2020

Ultra-Widefield Retinal Imaging for Analyzing the Association Between Types of Pathological Myopia and Posterior Staphyloma.

J Clin Med 2019 Sep 20;8(10). Epub 2019 Sep 20.

Department of Ophthalmology, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582, Japan.

High myopia may develop to pathologic myopia, which brings severe visual impairment; however, the etiology is not fully understood. We, therefore, investigated the relationship between the presence of posterior staphyloma and posterior ocular disorders by assessing the patients with high myopia. A retrospective study was performed for the patients, who have more than 26 mm of the axial length and of whom fundus photography was taken with an ultra-widefield retinal imaging system. The objectives were 138 cases encompassing 229 eyes. In 138 cases, 91 were bilateral and 47 were unilateral. The averages ± SD of axial length of bilateral and unilateral were 28.8 ± 2.2 mm, 27.3 ± 1.2 mm, respectively, showing statistically significant difference. The number of eyes with and without posterior staphyloma were 107 (46.7%) and 122 (53.3%), respectively. Retinal detachment and retinal breaks are more observed in cases without posterior staphyloma ( = 0.017). Myopic choroidal neovascularization (mCNV) ( = 0.002), chorioretinal atrophy ( < 0.001), retinoschisis ( < 0.001), and optic neuropathy ( = 0.038) are more often seen in cases with posterior staphyloma. In conclusion, the prevalence rates of myopic choroidal neovascularization, retinal choroidal atrophy, and optic neuropathy were significantly higher with posterior staphyloma. The rate of periocular disorders such as retinal detachment was significantly higher without posterior staphyloma. These results indicate associations between types of pathological myopia and presence or absence of posterior staphyloma analyzed by ultra-widefield retinal imaging.
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http://dx.doi.org/10.3390/jcm8101505DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6832756PMC
September 2019

Dynamic changes in choroidal conditions during anti-vascular endothelial growth factor therapy in polypoidal choroidal vasculopathy.

Sci Rep 2019 08 6;9(1):11389. Epub 2019 Aug 6.

Laboratory of Retinal Cell Biology, Keio University, School of Medicine, Tokyo, Japan.

We defined the relationships between initial choroidal conditions and their dynamics and exudative changes during anti-vascular endothelial growth factor (anti-VEGF) therapy in polypoidal choroidal vasculopathy (PCV). One hundred treatment-naïve eyes of 100 patients with PCV treated for 24 months at Keio University Hospital with intravitreal ranibizumab or aflibercept monotherapy (three injections and PRN thereafter) were retrospectively analyzed. Wet macula risk after three induction injections, which affected visual prognosis, was predicted by initial pachyvessels in the choroid (foveal greatest vertical choroidal vessel diameter [CVD] ≥180 μm) and pachychoroid (central choroidal thickness [CCT] ≥220 μm) recorded by optical coherence tomography. The risk for recurrent exudative change was greater in the pachyvessel groups irrespective of presence or absence of pachychoroid. Mean CVD and CCT decreased with anti-VEGF therapy when achieving a dry macula, suggesting that exudative changes are regulated by VEGF. Mean CVD and CCT at remission were greater in patients with initial pachyvessels and pachychoroid than in those without; the basal levels of CVD and CCT most likely represent VEGF-unrelated conditions. CVD increase preceded CCT increase and recurrent exudative changes, suggesting that the VEGF-related CVD increase may regulate CCT and exudative change; and that CVD may be a biomarker of exudative change.
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http://dx.doi.org/10.1038/s41598-019-47738-9DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6684594PMC
August 2019

Aquaporin 4 Suppresses Neural Hyperactivity and Synaptic Fatigue and Fine-Tunes Neurotransmission to Regulate Visual Function in the Mouse Retina.

Mol Neurobiol 2019 Dec 12;56(12):8124-8135. Epub 2019 Jun 12.

Department of Ophthalmology, Keio University School of Medicine, 35 Shinanomachi, Shinjukuku, Tokyo, 160-8582, Japan.

The bidirectional water channel aquaporin 4 (AQP4) is abundantly expressed in the neural tissue. The advantages and disadvantages of AQP4 neural tissue deficiency under pathological conditions, such as inflammation, and relationship with neural diseases, such as Alzheimer's disease, have been previously reported. However, the physiological functions of AQP4 are not fully understood. Here, we evaluated the role of AQP4 in the mouse retina using Aqp4 knockout (KO) mice. Aqp4 was expressed in Müller glial cells surrounding the synaptic area between photoreceptors and bipolar cells. Both scotopic and photopic electroretinograms showed hyperactive visual responses in KO mice, gradually progressing with age. Moreover, the amplitude reduction after frequent stimuli and synaptic fatigue was more severe in KO mice. Glutamine synthetase, glutamate aspartate transporter, synaptophysin, and the inward potassium channel Kir2.1, but not Kir4.1, were downregulated in KO retinas. KIR2.1 colocalized with AQP4 in Müller glial cells at the synaptic area, and its expression was affected by Aqp4 levels in primary Müller glial cell cultures. Intraocular injection of potassium in wild-type mice led to visual function hyperactivity, as observed in Aqp4 KO mice. Mitochondria molecules, such as Pgc1α and CoxIV, were downregulated, while apoptotic markers were upregulated in KO retinas. AQP4 may fine-tune synaptic activity, most likely by regulating potassium metabolism, at least in part, via collaborating with KIR2.1, and possibly indirectly regulating glutamate kinetics, to inhibit neural hyperactivity and synaptic fatigue which finally affect mitochondria and cause neurodegeneration.
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http://dx.doi.org/10.1007/s12035-019-01661-2DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6834759PMC
December 2019

QD laser eyewear as a visual field aid in a visual field defect model.

Sci Rep 2019 01 30;9(1):1010. Epub 2019 Jan 30.

Department of Ophthalmology, Keio University School of Medicine, Tokyo, Japan.

Visual field defects interfere with free actions and influence the quality of life of patients with retinitis pigmentosa; the prevalence of this disease is increasing in aging societies. Patients with progressive disease may require visual aids; however, no such devices are currently available. We utilized a retinal projection eyewear system, QD laser eyewear, which includes a projector inside the spectacle frame, to draw the image taken by a connected portable camera with a wide field lens. The images are projected onto the retina using a Maxwellian view optical system, which is not influenced by refractive error or the amount of incident light. Goldmann perimetry and figure recognition tests with the QD laser eyewear showed increased visual field areas and angles, and shortened the time for recognition of the number of figures in a sheet, in a limited visual field model that we developed by using a pin-hole system to simulate the tunnel vision of retinitis pigmentosa in 19 healthy adults. The device supported the quality of vision. Additionally, the visual field defect model used in healthy adults was useful for validating the device in the development stage of the study, to clarify both advantages and future goals for improving the device.
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http://dx.doi.org/10.1038/s41598-018-37744-8DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6353865PMC
January 2019