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Xiaolei Wang,1,2,* Jier Su,2,3,* Jingwen Ding,4 Song Han,2 Wei Ma,2,5 Hong Luo,2 Guy Hughes,6 Zhaoyang Meng,1 Yi Yin,1 Yanling Wang,1 Junfa Li2 1Department of Ophthalmology, Beijing Friendship Hospital, 2Department of Neurobiology, Beijing Institute for Brain Disorders, Capital Medical University, Beijing, 3Ningbo College of Health Sciences, Ningbo, 4Department of Ophthalmology, Beijing Tongren Hospital, Capital Medical University, Beijing, 5Beijing Stomatological Hospital, Capital Medical University, Beijing, People’s Republic of China; 6University of California, Irvine School of Medicine, Irvine, CA, USA *These authors contributed equally tothis work Objective: Ocular hypertension is an important risk factor for glaucoma. The purpose of this study was to investigate the gliotoxic effects of α-aminoadipic acid (AAA) in a rat model of AOH and its underlying mechanisms. Materials and methods: In the rat model of acute ocular hypertension (AOH), intraocular pressure was increased to 110mmHg for 60minutes. Animals were divided into four groups: sham operation (Ctrl), AOH, AOH + phosphate-buffered saline (PBS), and AOH + AAA. Cell apoptosis in the ganglion cell layer was detected with the terminal deoxynucleotidyl transferase-mediated uridine 5'-triphosphate-biotin nick end labeling (TUNEL) assay, and retinal ganglion cells (RGCs) immunostained with Thy-1 were counted. Müller cell activation was detected using immunostaining with glutamine synthetase and glial fibrillary acidic protein. Tumor necrosis factor-α (TNF-α) was examined using Western blot. Results: In the rat model of AOH, cell apoptosis was induced in the ganglion cell layer and the number of RGCs was decreased. Müller cell gliosis in the retinas of rats was induced, and retinal protein levels of TNF-α were increased. Intravitreal treatment of AAA versus PBS control attenuated these retinal abnormalities to show protective effects in the rat model of AOH. Conclusion: In the retinas of the rat model of AOH, AAA treatment attenuated retinal apoptosis in the ganglion cell layer and preserved the number of RGCs, likely through the attenuation of Müller cell gliosis and suppression of TNF-α induction. Our observations suggest that AAA might be a potential therapeutic target in glaucoma. Keywords: glaucoma, acute ocular hypertension, α-aminoadipic acid, retina, Müller cells, retinal ganglion cells, TNF-&alpha

Considerable time and effort has been spent removing nonnative ungulates from sensitive subalpine and forest areas in Hawai'i, with less effort dedicated to documenting changes in plant community structure after feral animal removal. Abundance of native and nonnative vegetation was quantified in a study comparing plots both before (1994) and 14 yr after (2008) removal of feral animals from windward East Maui subalpine and forest habitat in Waikamoi Preserve. An analysis of changes in abundance in two vegetation layers documented increases in relative cover of native subalpine vegetation: bryophytes tripled and lichens increased over nine times in the subalpine shrubland habitat within the ground cover (0 to 1 m) layer, and alien grass cover was halved. In the understory (1 to 2 m) layer, native ferns increased significantly, and native shrub cover tripled. In the forest habitat, bryophytes increased in both layers, and lichens increased in the understory layer. Higher-elevation plots in 2008 mor...

Age-related macular degeneration (AMD) is a common cause of blindness in older individuals. To accelerate the understanding of AMD biology and help design new therapies, we executed a collaborative genome-wide association study, including >17,100 advanced AMD cases and >60,000 controls of European and Asian ancestry. We identified 19 loci associated at P

PurposeTo determine whether there is an association between hepatic lipase (LIPC) and age-related macular degeneration (AMD) in two independent Caucasian cohorts.MethodsA discovery cohort of 1626 patients with advanced AMD and 859 normal controls and a replication cohort of 2159 cases and 1150 controls were genotyped for two single-nucleotide polymorphisms (SNPs) in the promoter region of LIPC. The associations between the SNPs and AMD were examined by χ(2) tests.ResultsIn the discovery cohort, rs493258 and rs10468017 were both associated with advanced AMD (P=9.63E-3 and P=0.048, respectively). The association was corroborated in the replication cohort (P=4.48E-03 for rs493258 and P=0.015 for rs10468017). Combined analysis resulted in even more significant associations (P=1.21E-04 for rs493258 and P=1.67E-03 for rs10468017).ConclusionThe LIPC promoter variants rs493258 and rs10468017 were associated with advanced AMD in two independent Caucasian populations, confirming that LIPC polymorphisms may be a genetic risk factor for AMD in the Caucasian population.

AimTo investigate clinical presentation and genotypes in patients with simultaneous geographic atrophy (GA) and choroidal neovascularization (CNV) and to compare with patients with GA or CNV only.Patients and methodsTwenty patients with combined CNV-GA and 154 CNV only and 154 GA only were chosen based on clinical exam and imaging. Six single-nucleotide polymorphisms (SNPs)-rs2274700 and rs1061170 (complement factor H), rs10490924 and rs11200638 (HTRA1/LOC387715), rs2230199 (C3), rs9332739 (C2)-were genotyped using the SNaPshot method. Chi-squared tests were used for genetic analysis.ResultsIn patients with CNV-GA, GA progressed slowly and often preceded CNV. CNV presented as subretinal haemorrhage or fluid, with a sudden drop in visual acuity (VA). Comparing combined CNV-GA to GA and CNV only, patients with both had a higher frequency of at-risk alleles at both SNPs within the HTRA1 gene-rs10490924 (52.5%), rs11200638 (52.6%). Statistical significance was not achieved. CNV-GA patients had no protective alleles at SNP rs9332739 (C2), compared with GA (27%) and CNV only (10%).ConclusionThere is a paucity of reports describing simultaneous CNV-GA. Clinical and genetic results may support the fact that GA and CNV fit on an age-related macular degeneration (AMD)-disease continuum and may clarify the disease processes in AMD.

To determine the genetic basis of myotonia congenita (MC) and strabismus in a large Caucasian family. Seven patients making up four generations of a family with MC and strabismus were recruited. All patients had at least one standard ophthalmic examination, including best-corrected visual acuity, refraction, and ocular motility measurements. CLCN1 and SCN4A genes were sequenced and analysed for mutations. Five out of the seven family members were diagnosed with MC by clinical history and electromyography. Ophthalmic history and exam revealed eyelid myotonia and strabismus. All patients with MC were diagnosed with strabismus between the ages of 3 and 6 and required surgical restoration of ocular alignment. Sequencing results revealed a c. 1333G>A; p. Val445Met mutation in the SCN4A gene. There are few reports describing eyelid myotonia and strabismus in patients diagnosed with MC. We found significant ocular involvement in a family with a mutation in SCN4A. Future studies may confirm that MC with significant ocular involvement can be used to direct genetic analysis.

To determine the genetic basis of early onset autosomal recessive Best vitelliform macular dystrophy (arBVMD) in a family with three affected children. Clinical and family-based genetic study. Seven subjects making up a family with three children affected by Best vitelliform macular dystrophy were studied. Standard ophthalmic exam with dilated ophthalmoscopy and imaging were performed in each individual. The eleven exons of BEST1were directly sequenced. All three affected children have the clinical characteristic features of Best vitelliform macular dystrophy: large macular vitelliform lesions, scattered vitelliform lesions along the arcades and in the peripheral retina, and an accumulation of serous retinal fluid. A novel compound heterozygous mutation in the BEST1gene was found in the three affected individuals (L41P and I201T). The unaffected parents and children only harbor one heterozygous mutation. arBVMD can be caused by the compound heterozygous mutation L41P and I201T in the BEST1gene.

Cystic fibrosis affects about 1 in 2500 live births and involves loss of transmembrane chloride flux due to a lack of a membrane protein channel termed the cystic fibrosis transmembrane conductance regulator (CFTR). We have studied CFTR structure by electron crystallography. The data were compared with existing structures of other ATP-binding cassette transporters. The protein was crystallized in the outward facing state and resembled the well characterized Sav1866 transporter. We identified regions in the CFTR map, not accounted for by Sav1866, which were potential locations for the regulatory region as well as the channel gate. In this analysis, we were aided by the fact that the unit cell was composed of two molecules not related by crystallographic symmetry. We also identified regions in the fitted Sav1866 model that were missing from the map, hence regions that were either disordered in CFTR or differently organized compared with Sav1866. Apart from the N and C termini, this indicated that in CFTR, the cytoplasmic end of transmembrane helix 5/11 and its associated loop could be partly disordered (or alternatively located).

The rs1061170T/C variant encoding the Y402H change in complement factor H (CFH) has been identified by genome-wide association studies as being significantly associated with age-related macular degeneration (AMD). However, the precise mechanism by which this CFH variant impacts the risk of AMD remains largely unknown. Oxidative stress plays an important role in many aging diseases, including cardiovascular disease and AMD. A large amount of oxidized phospholipids (oxPLs) are generated in the eye because of sunlight exposure and high oxygen content. OxPLs bind to the retinal pigment epithelium and macrophages and strongly activate downstream inflammatory cascades. We hypothesize that CFH may impact the risk of AMD by modulating oxidative stress. Here we demonstrate that CFH binds to oxPLs. The CFH 402Y variant of the protective rs1061170 genotype binds oxPLs with a higher affinity and exhibits a stronger inhibitory effect on the binding of oxPLs to retinal pigment epithelium and macrophages. In addition, plasma from non-AMD subjects with the protective genotype has a lower level of systemic oxidative stress measured by oxPLs per apolipoprotein B (oxPLs/apoB). We also show that oxPL stimulation increases expression of genes involved in macrophage infiltration, inflammation, and neovascularization in the eye. OxPLs colocalize with CFH in drusen in the human AMD eye. Subretinal injection of oxPLs induces choroidal neovascularization in mice. In addition, we show that the CFH risk allele confers higher complement activation and cell lysis activity. Together, these findings suggest that CFH influences AMD risk by modulating oxidative stress, inflammation, and abnormal angiogenesis.

Very long chain polyunsaturated fatty acid (VLC-PUFA)-containing glycerophospholipids are highly enriched in the retina; however, details regarding the specific synthesis and function of these highly unusual retinal glycerophospholipids are lacking. Elongation of very long chain fatty acids-4 (ELOVL4) has been identified as a fatty acid elongase protein involved in the synthesis of VLC-PUFAs. Mutations in ELOVL4 have also been implicated in an autosomal dominant form of Stargardt disease (STGD3), a type of juvenile macular degeneration. We have generated photoreceptor-specific conditional knock-out mice and used high performance liquid chromatography-mass spectrometry (HPLC-MS) to examine and analyze the fatty acid composition of retinal membrane glycerophosphatidylcholine and glycerophosphatidylethanolamine species. We also used immunofluorescent staining and histology coupled with electrophysiological data to assess retinal morphology and visual response. The conditional knock-out mice showed a significant decrease in retinal glycerophospholipids containing VLC-PUFAs, specifically contained in the sn-1 position of glycerophosphatidylcholine, implicating the role of Elovl4 in their synthesis. Conditional knock-out mice were also found to have abnormal accumulation of lipid droplets and lipofuscin-like granules while demonstrating photoreceptor-specific abnormalities in visual response, indicating the critical role of Elovl4 for proper rod or cone photoreceptor function. Altogether, this study demonstrates the essential role of ELOVL4 in VLC-PUFA synthesis and retinal function.

Background Truncation mutations in the elongation of very long chain fatty acids-4 (AF277094, MIM #605512) (ELOVL4) gene cause Stargardt-like macular dystrophy type 3 (STGD3). Mice expressing truncated ELOVL4 develop rapid retinal degeneration, but are poor STGD3 models since mice lack a macula. Photoreceptor topography in the pig retina is more similar to that in humans as it includes the cone rich, macula-like area centralis. The authors generated transgenic pigs expressing human disease-causing ELOVL4 mutations to better model the pathobiology of this macular disease. Methods Pronuclear DNA microinjection and somatic cell nuclear transfer were used to produce transgenic pigs for two different ELOVL4 mutations: the 5 base pair deletion (5 bpdel) and the 270 stop mutation (Y270terEYFP). Retinal transgene expression, morphology and electrophysiology were examined. Results The authors obtained four lines of Y270terEYFP and one line of 5 bpdel transgenic animals. Direct fluorescence microscopy indicated that the Y270terEYFP protein is expressed in photoreceptors and mislocalised within the cell. Immunohistochemical examination of transgenic pigs showed photoreceptor loss and disorganised inner and outer segments. Electroretinography demonstrated diminished responses in both transgenic models. Conclusions These transgenic pigs provide unique animal models for examining macular degeneration and STGD3 pathogenesis.

Objectives To evaluate the independent and joint effects of genetic factors and environmental variables on advanced forms of age-related macular degeneration (AMD), including geographic atrophy and choroidal neovascularization, and to develop a predictive model with genetic and environmental factors included. Methods Demographic information, including age at onset, smoking status, and body mass index, was collected for 1844 participants. Genotypes were evaluated for 8 variants in 5 genes related to AMD. Unconditional logistic regression analyses were performed to generate a risk predictive model. Results All genetic variants showed a strong association with AMD. Multivariate odds ratios were 3.52 (95% confidence interval, 2.08-5.94) for complement factor H, CFH rs1061170 CC, 4.21 (2.30-7.70) for CFH rs2274700 CC, 0.46 (0.27-0.80) for C2 rs9332739 CC/CG, 0.44 (0.30-0.66) for CFB rs641153 TT/CT, 10.99 (6.04-19.97) for HTRA1/LOC387715 rs10490924 TT, and 2.66 (1.43-4.96) for C3 rs2230199 GG. Smoking was independently associated with advanced AMD after controlling for age, sex, body mass index, and all genetic variants. Conclusion CFH confers more risk to the bilaterality of geographic atrophy, whereas HTRA1/LOC387715 contributes more to the bilaterality of choroidal neovascularization. C3 confers more risk for geographic atrophy than choroidal neovascularization. Risk models with combined genetic and environmental factors have notable discrimination power. Clinical Relevance Early detection and risk prediction of AMD could help to improve the prognosis of AMD and to reduce the outcome of blindness. Targeting high-risk individuals for surveillance and clinical interventions may help reduce disease burden.

The statistical power of genome-wide association (GWA) studies to detect risk alleles for human diseases is limited by the unfavorable ratio of SNPs to study subjects. This multiple testing problem can be surmounted with very large population sizes when common alleles of large effects give rise to disease status. However, GWA approaches fall short when many rare alleles may give rise to a common disease, or when the number of subjects that can be recruited is limited. Here, we demonstrate that this multiple testing problem can be overcome by a comparative genomics approach in which an initial genome-wide screen in a genetically amenable model organism is used to identify human orthologues that may harbor risk alleles for adult-onset primary open angle glaucoma (POAG). Glaucoma is a major cause of blindness, which affects over 60 million people worldwide. Several genes have been associated with juvenile onset glaucoma, but genetic factors that predispose to adult onset primary open angle glaucoma (POAG) remain largely unknown. Previous genome-wide analysis in a Drosophila ocular hypertension model identified transcripts with altered regulation and showed induction of the unfolded protein response (UPR) upon overexpression of transgenic human glaucoma-associated myocilin (MYOC). We selected 16 orthologous genes with 62 polymorphic markers and identified in two independent human populations two genes of the UPR that harbor POAG risk alleles, BIRC6 and PDIA5. Thus, effectiveness of the UPR in response to accumulation of misfolded or aggregated proteins may contribute to the pathogenesis of POAG and provide targets for early therapeutic intervention. © 2011 Carbone et al.

PURPOSE We investigated the association of genetic factors with primary open angle glaucoma (POAG), including high tension glaucoma (HTG) and normal tension glaucoma (NTG), in a Han Chinese population. METHODS We recruited 1157 POAG cases, including 860 HTG and 297 NTG, and 934 normal controls. A total of 13 previously reported single nucleotide polymorphisms (SNPs) located at four gene regions (TMCO1, CDKN2B-AS1, ATOH7, and SIX1/SIX6) was genotyped. Distributions of allele frequencies were compared between cases and controls as well as in the HTG and NTG subgroups. The IOP, vertical cup-to-disc ratio (VCDR), central corneal thickness (CCT), axial length (AL), and age at diagnosis also were investigated as quantitative phenotypes with genotypes of these SNPs. RESULTS The SNPs rs4656461 and rs7555523 at TMCO1, rs523096 and rs2157719 at CDKN2B-AS1, as well as rs33912345 and rs10483727 at SIX1/SIX6 showed statistically significant association with POAG. The SNPs at ATOH7 did not show statistically significant association with POAG in our dataset. In the subgroup analysis of HTG and NTG, multiple variants at CDKN2B-AS1 and SIX1/SIX6 showed stronger association with NTG than HTG. The SNPs rs523096 and rs2157719 at CDKN2B-AS1 as well as rs33912345 and rs10483727 at SIX1/SIX6 were found to be associated with IOP where the minor alleles were associated with an increase in IOP. In contrast, SNPs at TMCO1 showed significant association with HTG only. CONCLUSIONS Genetic variants in CDKN2B-AS1, SIX1/SIX6, and TMCO1 were associated with POAG in a Han Chinese population. Genes CDKN2B-AS1 and SIX1/SIX6 seem to harbor a tendency toward POAG with lower IOP, while carriers of risk alleles at TMCO1 seem to be predisposed to developing POAG with higher IOP.

PURPOSE To investigate the association of PLEKHA7 and COL11A1 with primary angle closure glaucoma, as well as acute and chronic subphenotype, in a Han Chinese population. METHODS A total of 984 cases, including 606 primary angle closure glaucoma (PACG) and 378 primary angle closure (PAC), and 922 normal controls were recruited. Twelve single nucleotide polymorphisms (SNPs) (rs1676486, rs3753841, rs12138977, rs2126642, rs2622848, rs216489, rs1027617, rs366590, rs11024060, rs6486330, rs11024097, and rs11024102) in the PLEKHA7 gene and COL11A12 gene were genotyped. Distributions of allele frequencies were compared between cases and controls as well as in patient subgroups with or without acute attacks. RESULTS Four of the 12 SNPs, including rs1676486 (P = 0.0060) and rs12138977 (P = 0.028) in COL11A1, as well as rs216489 (P = 0.0074) and rs11024102 (P = 0.038) in PLEKHA7, were found to have a statistically significant association with PAC/PACG. In the subgroup analysis, 6 out of 12 SNPs (rs1676486, rs3753841, rs12138977, rs216489, rs11024060, and rs11024102) showed statistically significant differences between acute PAC/PACG cases and controls. However, none of them showed statistically significant differences between chronic PAC/PACG cases and controls. CONCLUSIONS Our study suggests that rs1676486 and rs12138977 in COL11A1 as well as rs216489 and rs11024102 in PLEKHA7 are associated with an increased risk of PAC/PACG in the Han Chinese population, supporting prior reports of the association of COL11A1 and PLEKH7 with angle closure glaucoma. Both COL11A1 and PLEKHA7 were shown to confer significant risk for acute PAC/PACG. Further work is necessary to confirm the importance of COL11A1 and PLEKHA7 in the pathogenesis of glaucoma.