Molecular Vision[JOURNAL]
Sun
200 papers
Prevalence of primary mutations in Leber hereditary optic neuropathy: A five-year report from a tertiary eye care center in India.
Sundaramurthy S, Selvakumar A, Dharani V … +6 more , Soumittra N, Mani J, Thirumalai K, Periyasamy P, Mathavan S, Sripriya S
Mol Vis · 2021 · PMID 35035206
PURPOSE: Genetic testing for primary mutations m.3460G>A, m.11778G>A, and m.14484T>C in and genes of mitochondrial DNA is the recommended assay for Leber hereditary optic neuropathy (LHON; OMIM 535000). This report dis...
PURPOSE: Genetic testing for primary mutations m.3460G>A, m.11778G>A, and m.14484T>C in and genes of mitochondrial DNA is the recommended assay for Leber hereditary optic neuropathy (LHON; OMIM 535000). This report discusses the outcome of molecular genetic screening for these three primary mutations in suspected LHON cases in India. METHODS: Two hundred and seventy-eight unrelated presumed LHON patients who were seen at the neuro-ophthalmology clinic of a tertiary eye care center from 2014-2018 were analyzed. They were genotyped for the three common variants by polymerase chain reaction-based direct sequencing, and their plasmy status was also determined by restriction enzyme digestion. RESULTS: Eighty two of 278 patients were positive for one of the 3 common mutations with m.11778G>A in gene more frequently distributed (N=72) in homoplasmic state (N=59/82). The mean onset age of visual loss was 21.1years (SD, 9.8 years; range, 5-58 years) in patients harboring the primary mutation. The most common clinical presentation was bilateral sequential painless vision loss with central and cecocentral scotomas in the visual field due to optic disc atrophy. CONCLUSIONS: The study subjects are a sample of a much larger number of suspected LHON cases tested for primary mutations in India. (N= 278) and 29.4% (82/278) of patients harbour one of the 3 common mutations. Screening the entire mitochondrial genome and the other nuclear genes encoding mitochondrial protein, would probably aid in identifying the other less common mtDNA mutations causing LHON in Indian population.
Mutational screening of , , , , , and in a Chinese cohort of 103 patients with nonsyndromic high myopia.
Zheng YH, Cai XB, Xia LQ … +8 more , Zhou FY, Wen XR, Chen DF, Han F, Zhou KJ, Jin ZB, Zhuang WJ, Lin B
Mol Vis · 2021 · PMID 35002215
PURPOSE: High myopia (HM) is one of the leading causes of irreversible vision loss in the world. Many myopia loci have been uncovered with linkage analysis, genome-wide association studies, and sequencing analysis. Numer...
PURPOSE: High myopia (HM) is one of the leading causes of irreversible vision loss in the world. Many myopia loci have been uncovered with linkage analysis, genome-wide association studies, and sequencing analysis. Numerous pathogenic genes within these loci have been detected in a portion of HM cases. In the present study, we aimed to investigate the genetic basis of 103 patients with nonsyndromic HM, focusing on the reported causal genes. METHODS: A total of 103 affected individuals with nonsyndromic HM were recruited, including 101 patients with unrelated sporadic HM and a mother and son pair. All participants underwent comprehensive ophthalmic examinations, and genomic DNA samples were extracted from the peripheral blood. Whole exome sequencing was performed on the mother and son pair as well as on the unaffected father. Sanger sequencing was used to identify mutations in the remaining 101 patients. Bioinformatics analysis was subsequently applied to verify the mutations. RESULTS: An extremely rare mutation in (c.2627A>T, p.K876M) was identified in the mother and son pair but not in the unaffected father. Another two mutations in (c.4787C>T, p.P1596L/c.5056G>A, p.G1686S) were identified in two unrelated patients. A total of eight heterozygous variants potentially affecting the protein function were detected in eight of the remaining 99 patients, including c.1350delC, p.V451Cfs*76 and c.1023_1024insA, p.P342Tfs*41 in ; c.244_246delAAG, p.K82del in ; c.545A>G, p.Y182C in ; c.415C>T, p.P139S in ; c.3266A>G, p.Y1089C in ; and c.2252C>T, p.S751L and c.1708C>T, p.R570C in . Multiple bioinformatics analyses were conducted, and a comparison to a group with geographically matched controls was performed, which supported the potential pathogenicity of these variants. CONCLUSIONS: We provide further evidence for the potential role of in HM inheritance and enlarged the current genetic spectrum of nonsyndromic HM by comprehensively screening the reported causal genes.
Tissue plasminogen activator rescues steroid-induced outflow facility reduction via non-enzymatic action.
Gindina S, Barron AO, Hu Y … +2 more , Dimopoulos A, Danias J
Mol Vis · 2021 · PMID 35002214
PURPOSE: Tissue plasminogen activator (tPA) prevents steroid-induced reduction in aqueous humor outflow facility; however, its mechanism of action at the trabecular meshwork (TM) remains unclear. Enzymatic and non-enzyma...
PURPOSE: Tissue plasminogen activator (tPA) prevents steroid-induced reduction in aqueous humor outflow facility; however, its mechanism of action at the trabecular meshwork (TM) remains unclear. Enzymatic and non-enzymatic domains allow tPA to function as both an enzyme and a cytokine. This study sought to determine whether cytokine activity is sufficient to rescue steroid-induced outflow facility reduction. METHODS: Outflow facility was measured in C57BL/6J mice following triamcinolone acetonide exposure and either transfection of the TM using adenoviral vectors, encoding for enzymatically active and inactive tPA, or administration of the respective proteins. Protein injections were also administered to tPA deficient (KO) and deficient (KO) mice to determine the potential to rescue reductions in outflow facility and determine downstream mechanisms. Gene expression of matrix metalloproteinases (, and ) was measured in angle ring tissues containing the TM. RESULTS: Enzymatically active and inactive tPA (either produced after TM transfection or after direct administration) were equally effective in attenuating steroid-induced outflow facility reduction in C57BL/6J mice. They were also equally effective in rescuing outflow reduction in KO mice and causing enhanced expression of matrix metalloproteinases. However, both enzymatically active and enzymatically inactive tPA did not improve outflow reduction in KO mice or increase the baseline outflow facility in naïve C57BL/6J mice. CONCLUSIONS: tPA enzymatic activity is not necessary in the regulation of aqueous humor outflow. tPA can increase the expression of matrix metalloproteinases in a cytokine-mediated fashion. This cascade of events may eventually lead to extracellular matrix remodeling at the TM, which reverses outflow facility reduction caused by steroids.
Lacrimal gland homeostasis is maintained by the pathway by attenuating endoplasmic reticulum stress inflammation in the lacrimal gland of knockout mice.
Hu S, Di G, Cao X … +5 more , Liu Y, Wang Y, Zhao H, Wang D, Chen P
Mol Vis · 2021 · PMID 35002213
PURPOSE: AQP5 mice spontaneously exhibit dry eye symptoms. The purpose of this study was to assess the endoplasmic reticulum (ER) stress-mediated inflammation generated by a deficiency of aquaporin 5 (AQP5) in the lacrim...
PURPOSE: AQP5 mice spontaneously exhibit dry eye symptoms. The purpose of this study was to assess the endoplasmic reticulum (ER) stress-mediated inflammation generated by a deficiency of aquaporin 5 (AQP5) in the lacrimal gland. METHODS: Hematoxylin and eosin (H&E) staining, Oil Red O staining, and transmission electron microscopy (TEM) analysis were performed to identify structural changes in lacrimal gland epithelial cells because of AQP5 deficiency. Corneal epithelial defects were assessed with sodium fluorescein staining. The expression profiles of mRNA and proteins were determined by quantitative real-time reverse transcription PCR (qRT-PCR) and western blot. Mice in the quercetin group were injected intraperitoneally with 40 mg/kg of quercetin, and the control group was injected with an equal volume of dimethyl sulfoxide (DMSO) for 4 weeks. RESULTS: Aqueous tear secretion fell at about 50% in 1- and 6-month-old AQP5 mice compared with that of AQP5 mice. TEM showed that the ER structure was damaged. ER stress was significantly increased in the lacrimal gland of AQP5 mice. Lipid droplets accumulated in the matrix and acinar cells, and changes occurred in the lipid metabolism and gene expression levels for , , and in the AQP5 mice. Immune cell infiltration and increases in the gene expression levels of the chemokines , , and were found in the lacrimal gland of AQP5 mice. Quercetin partially reversed ER stress levels, inflammation, and lipid accumulation, and it inhibited tear secretion. CONCLUSIONS: The study data indicated that a deficiency of AQP5 induced pathophysiological changes and functional decompensation of the lacrimal gland. Quercetin may improve the inflammation in the lacrimal glands of AQP5 mice by regulating the ER stress levels.
Collagen matrix perturbations in corneal stroma of Ossabaw mini pigs with type 2 diabetes.
Sinha NR, Balne PK, Bunyak F … +4 more , Hofmann AC, Lim RR, Mohan RR, Chaurasia SS
Mol Vis · 2021 · PMID 35002212
PURPOSE: Diabetes mellitus (DM) is a metabolic disorder that affects over 450 million people worldwide. DM is characterized by hyperglycemia, causing severe systemic damage to the heart, kidneys, skin, vasculature, nerve...
PURPOSE: Diabetes mellitus (DM) is a metabolic disorder that affects over 450 million people worldwide. DM is characterized by hyperglycemia, causing severe systemic damage to the heart, kidneys, skin, vasculature, nerves, and eye. Type 2 diabetes (T2DM) constitutes 90% of clinical cases and is the most common cause of blindness in working adults. Also, about 70% of T2DM patients show corneal complications including delayed wound healing, often described as diabetic keratopathy (DK). Despite the increasing severity of DM, the research on DK is bleak. This study investigated cellular morphology and collagen matrix alterations of the diabetic and non-diabetic corneas collected from Ossabaw mini pigs, a T2DM animal model with a "thrifty genotype." METHODS: Pig corneas were collected from six-month-old Ossabaw miniature pigs fed on a western diet (WD) for ten weeks. The tissues were processed for immunohistochemistry and analyzed using hematoxylin and eosin staining, Mason Trichrome staining, Picrosirus Red staining, Collage I staining, and TUNEL assay. mRNA was prepared to quantify fibrotic gene expression using quantitative reverse-transcriptase PCR (qRT-PCR). Transmission electron microscopy (TEM) was performed to evaluate stromal fibril arrangements to compare collagen dynamics in WD standard diet (SD) fed Ossabaw pig corneas. RESULTS: Ossabaw mini pigs fed on a WD for 10 weeks exhibit classic symptoms of metabolic syndrome and hyperglycemia seen in T2DM patients. We observed significant disarray in cornea stromal collagen matrix in Ossabaw mini pigs fed on WD compared to the age-matched mini pigs fed on a standard chow diet using Masson Trichome and Picrosirius Red staining. Furthermore, ultrastructure evaluation using TEM showed alterations in stromal collagen fibril size and organization in diabetic corneas compared to healthy age-matched corneas. These changes were accompanied by significantly decreased levels of Collagen IV and increased expression of matrix metallopeptidase 9 in WD-fed pigs. CONCLUSIONS: This pilot study indicates that Ossabaw mini pigs fed on WD showed collagen disarray and altered gene expression involved in wound healing, suggesting that corneal stromal collagens are vulnerable to diabetic conditions.
Increased lacrimal inflammatory mediators in patients with keratoconus.
Moura GS, Santos A, Cenedeze MA … +4 more , Hiyane MI, Camara NOS, Barbosa de Sousa L, Augusto de Oliveira L
Mol Vis · 2021 · PMID 35002211
PURPOSE: This study aimed to characterize the tear film immunologic profile in keratoconus (KC) patients compared with healthy individuals (control group) and to investigate the correlation between the tear film immunolo...
PURPOSE: This study aimed to characterize the tear film immunologic profile in keratoconus (KC) patients compared with healthy individuals (control group) and to investigate the correlation between the tear film immunologic profile and atopy, disease severity, and disease status over time. METHODS: The study involved 30 KC patients and 18 healthy individuals. Tear collection was obtained using microcapillary tubes. Tear film levels of fractalkine, granulocyte-macrophage colony-stimulating factor (GM-CSF), interferon (IFN)-γ, interleukin (IL)-1β, IL-2, IL-4, IL-5, IL-6, IL-7, IL-8, IL-10, IL-12, IL-13, IL-17A, IL-21, IL-23, interferon-inducible T-cell alpha chemoattractant (ITAC), macrophage inflammatory protein-1 alpha (MIP-1α), MIP-1β, MIP-3α, and tumor necrosis factor (TNF)-α were detected. Keratometric measurements and topographic patterns were used to diagnose and define disease progression. Tear immunologic profiles were compared, emphasizing the presence or absence of ocular allergy. Correlations between the cytokine profile, disease severity, and disease status were also analyzed longitudinally in the KC patients. RESULTS: Lacrimal cytokine concentrations were higher in the KC patients than they were in the controls in 14 of 21 cytokines analyzed. IL-6 was the most relevant cytokine found in KC patients, especially when associated with ocular allergy. There was no correlation between KC progression and the level of inflammatory cytokines when analyzed longitudinally. KC severity correlated with IL-6 concentration, where the more severe KC presented a higher IL-6 concentration in tears. CONCLUSIONS: Inflammatory activity seems to be involved in the pathogenesis of KC. Out of 21 cytokines, 14 were more concentrated in the tears of KC patients than healthy subjects. IL-6 was significantly higher in KC patients' tears and was related to disease severity. Disease progression did not correlate with cytokine levels when analyzed longitudinally.
Epigenetic alterations associated with dexamethasone sodium phosphate through DNMT and TET in RPE cells.
Liu W, Mohan SP, Nagaraj NR … +4 more , Sundar Jaganathan S, Wen Y, Ramasubramanyan S, Irudayaraj J
Mol Vis · 2021 · PMID 34924744
PURPOSE: To elucidate the mechanism behind epigenetic alteration associated with dexamethasone (DEX) sodium phosphate treatment. METHODS: We performed enzyme-linked immunosorbent assay to quantify changes in global DNA m...
PURPOSE: To elucidate the mechanism behind epigenetic alteration associated with dexamethasone (DEX) sodium phosphate treatment. METHODS: We performed enzyme-linked immunosorbent assay to quantify changes in global DNA methylation and hydroxymethylation, quantitative real-time PCR (qRT-PCR) of the DNA methylation- and hydroxymethylation-related gene, in vitro DNA methyltransferase (DNMT) enzymatic activity assays with purified DNMTs, and DNA hydroxymethylation pattern with super-resolution imaging. RESULTS: We identified global DNA hypomethylation and hyper-hydroxymethylation upon DEX treatment, associated with aberrant mRNA expression levels of DNMT and ten-eleven translocation (TET) proteins. Additionally, DEX exposure could directly hinder DNMT activities. CONCLUSIONS: We showed that DEX-induced epigenetic alterations are linked to aberrant DNMT and TET expression, potentially through an essential role of DNMT.
Five novel copy number variations detected in patients with familial exudative vitreoretinopathy.
Luo J, Li J, Zhang X … +4 more , Li JK, Chen HJ, Zhao PQ, Fei P
Mol Vis · 2021 · PMID 34924743
PURPOSE: Familial exudative vitreoretinopathy (FEVR) is an inherited retinal vascular disease genetically heterogeneous with multiple causative genes. The aim of this study is to report five novel copy number variation (...
PURPOSE: Familial exudative vitreoretinopathy (FEVR) is an inherited retinal vascular disease genetically heterogeneous with multiple causative genes. The aim of this study is to report five novel copy number variation (CNV) regions in FEVR patients and to investigate the possible contributions of novel CNVs to FEVR. METHODS: In this study, 824 FEVR families were collected. All cases were performed using the targeted next generation sequencing (NGS) assay, and families with no definite pathogenic mutations in FEVR genes were screened for CNVs according to the NGS results. Droplet digital polymerase chain reaction (ddPCR) testing was introduced to validate the screened CNV regions. We also reviewed the clinical presentations of the probands and affected family members associated with the novel CNVs and conducted segregation analysis. RESULTS: Five CNVs in five patients were detected in this study: heterozygous deletions of kinesin family member 11 () exons 2-4, KIF11 exon 11, KIF11 exons 1-10, tetraspanin-12 () exons 1-3, and low-density lipoprotein receptor-related protein 5 () exons 19-21. Among the five affected families, exons 1-3 heterozygous deletion and exons 19-21 heterozygous deletion originate from the mother and the father of the proband, respectively. No other family members manifested as FEVR except for the probands. The correlation between disease severity and CNV loci seems uncertain. CONCLUSIONS: Five novel CNV loci in FEVR patients were uncovered in this study, including one maternally-inherited and one paternally-inherited CNV region. Though there is no evidence of co-segregation between these CNVs and FEVR, our findings suggest novel genetic risk factors for FEVR.
Anti-tumor necrosis factor alpha reduces the proangiogenic effects of activated macrophages derived from patients with age-related macular degeneration.
Hagbi-Levi S, Tiosano L, Rinsky B … +5 more , Levinger N, Elbaz-Hayoun S, Carmi S, Grunin M, Chowers I
Mol Vis · 2021 · PMID 34924742
PURPOSE: Macrophages are believed to promote choroidal neovascularization (CNV) in neovascular age-related macular degeneration (nvAMD); however, the underlying proangiogenic mechanism is poorly understood. Therefore, we...
PURPOSE: Macrophages are believed to promote choroidal neovascularization (CNV) in neovascular age-related macular degeneration (nvAMD); however, the underlying proangiogenic mechanism is poorly understood. Therefore, we examined this mechanism in proinflammatory macrophages derived from patients with nvAMD. METHODS: Monocytes were isolated from patients with nvAMD and polarized to form an M1 proangiogenic phenotype. We then screened for the role of proangiogenic cytokines expressed by these macrophages, including TNF-α, VEGF, IL-6, IL-8, and IL-1β, using an ex vivo choroid sprouting assay and an in vivo rodent model of laser-induced CNV (LI-CNV). We also examined the value of inhibiting TNF-α inhibition with respect to reducing the proangiogenic effects of M1 macrophages. Finally, we analyzed the macrophage cytokine expression database to evaluate the feasibility of modulating the expression of TNF-α. RESULTS: The cytokines above are expressed at high levels in patient-derived M1 macrophages. However, among the cytokines tested only TNF-α significantly increased choroid sprouting. Moreover, adoptive intravitreal transfer of M1 macrophages significantly increased LI-CNV, and blocking TNF-α abolished the proangiogenic effects of M1 macrophages in both models. An analysis of cytokine expression revealed that >50% of TNF-α expression is determined by modifiable factors. CONCLUSIONS: Blocking TNF-α can reduce the proangiogenic effects of M1 macrophages in nvAMD. Thus, activated macrophages may represent a potential therapeutic target for altering TNF-α expression in nvAMD.
Mapping retinal ganglion cell somas in a large-eyed glaucoma model.
Adelman SA, Oikawa K, Senthilkumar G … +3 more , Trane RM, Teixeira LBC, McLellan GJ
Mol Vis · 2021 · PMID 34924741
PURPOSE: The purpose of this study was to identify a robust, representative region of interest (ROI) for studies of retinal ganglion cell (RGC) soma loss in feline congenital glaucoma (FCG), a spontaneous, large-eyed gla...
PURPOSE: The purpose of this study was to identify a robust, representative region of interest (ROI) for studies of retinal ganglion cell (RGC) soma loss in feline congenital glaucoma (FCG), a spontaneous, large-eyed glaucoma model. METHODS: Seven FCG and three wild-type (wt) eyes were collected from 10 adult cats of both sexes. Eyes enucleated postmortem were immediately fixed overnight in 4% paraformaldehyde and then stored in 0.1 M PBS at 4 °C. The retinas were wholemounted, Nissl stained with cresyl violet, and imaged using light microscopy. Somas of RGCs were manually identified according to long-established morphological criteria and quantified using a semiautomated method; their coordinates were used to create density maps and plots of the retinal topography. The RGC axon counts for the corresponding eyes were obtained from glutaraldehyde-fixed, resin-embedded optic nerve cross-sections stained with 0.1% p-phenylenediamine (PPD) using a semiautomated counting method. Correlations between total optic nerve axons and RGC soma counts were assessed by linear regression. A k-means cluster algorithm was used to identify a retinal ROI, with further definition using a probability density algorithm. RESULTS: Interindividual variability in RGC total soma counts was more pronounced in FCG cats (mean = 83,244, range: 0-155,074) than in wt cats (mean = 117,045, range: 97,373-132,972). In general, RGC soma counts were lower in FCG cats than they were in wt cats. RGC axon counts in the optic nerve cross-sections were lower than, but strongly correlated to, the total RGC soma count across all cats (in wt and FCG retinas; R = 0.88) and solely FCG eyes (R = 0.92). The k-means cluster algorithm indicated a region of the greatest mean difference between the normal wt retinas and FCG-affected retinas within the temporal retina, incorporating the region of the area centralis. CONCLUSIONS: As in other species, RGC soma count and topography are heterogeneous between individual cats, but we identified an ROI in the temporal retina for future studies of RGC soma loss or preservation in a large-eyed model of congenital glaucoma. Many of the methods refined and established to facilitate studies in this FCG model will be broadly applicable to studies in other large-eyed models.
A convenient test system for the identification of CYP4V2 inhibitors.
Sharma S, Liu S, Durairaj P … +3 more , Machalz D, Wolber G, Bureik M
Mol Vis · 2021 · PMID 34880593
PURPOSE: Polymorphisms in the gene that codes for the human cytochrome P450 enzyme CYP4V2 are a cause of Bietti crystalline dystrophy (BCD). Therefore, inhibition of CYP4V2 activity may well be a cause of visual disabili...
PURPOSE: Polymorphisms in the gene that codes for the human cytochrome P450 enzyme CYP4V2 are a cause of Bietti crystalline dystrophy (BCD). Therefore, inhibition of CYP4V2 activity may well be a cause of visual disability. However, monitoring the fatty acid hydroxylation reactions catalyzed by this enzyme is tedious and not well suited for inhibitor screening. METHODS: We investigated the use of proluciferin compounds as probe substrates for efficient and convenient determination of CYP4V2 activity. RESULTS: Ten proluciferins were tested for conversion by CYP4V2, and eight were found to be substrates of this enzyme. One point inhibitor assays were performed using luciferin 6' 3-furfuryl ether methyl ester (luciferin-3FEME) as the probe substrate and 12 test compounds. As expected, HET0016 had by far the strongest effect, while two other compounds (including osilodrostat) also displayed statistically significant inhibitory potency. The half maximal inhibitory concentration (IC) for HET0016 was determined to be 179 nM. A recently identified potent inhibitor of human CYP4Z1 was found not to inhibit CYP4V2. To explore the selectivity of this compound between CYP4Z1 and CYP4V2, we developed a homology model of CYP4V2 and conducted docking experiments. CONCLUSIONS: We provide the first protocol for a robust and convenient CYP4V2 inhibitor assay that does not depend on fatty acid analysis but can be simply monitored with luminescence. Moreover, we demonstrate additional evidence for the concern that compounds with CYP-inhibitory properties may inhibit CYP4V2 activity and thus, possibly cause visual disability.
A deep intronic substitution in is one of the major causes of achromatopsia among Jewish patients.
Aweidah H, Salameh M, Yahalom C … +6 more , Blumenfeld A, Macarov M, Weisschuh N, Kohl S, Banin E, Sharon D
Mol Vis · 2021 · PMID 34703197
PURPOSE: Although most (or even all) genes that can cause achromatopsia (ACHM) when mutated are known, some patients are still negative for mutations even after screening the coding sequence of all known genes. Our aim w...
PURPOSE: Although most (or even all) genes that can cause achromatopsia (ACHM) when mutated are known, some patients are still negative for mutations even after screening the coding sequence of all known genes. Our aim was to characterize the genetic and clinical aspects of a deep intronic (c.1663-1205G>A, IVS14-1205G>A) variant. METHODS: Clinical evaluation included visual acuity testing, refractive error, a full clinical eye exam, full-field electroretinography (ffERG), color vision testing, and retinal imaging. Genetic analysis of exons, as well as part of intron 14, was performed by Sanger sequencing of PCR products. RESULTS: Screening for the c.1663-1205G>A variant revealed 17 patients belonging to 12 unrelated families who were either homozygous for this variant (7 cases, 5 families) or heterozygous in combination with another heterozygous known mutation (10 cases, 7 families). All patients were diagnosed with cone-dominated disease, mainly complete ACHM. In all cases, the disease had an early, congenital onset. Visual acuity was markedly impaired, ranging between 0.07 and 0.32 on the Early Treatment Diabetic Retinopathy Study (ETDRS) scale (logarithm of the minimum angle of resolution [LogMAR] +1.18 to +0.50), with a mean visual acuity of 0.15 ETDRS (LogMAR +0.80). Additional typical signs of ACHM, including impaired color vision, light aversion, and nystagmus, were also noted in all patients. As is common in ACHM, fundus exams were largely unremarkable in most patients, with mild foveal RPE changes seen in some cases at older ages. ERG was available for 14 out of 17 patients, and in all of them-including infants from the age of 6 months-cone responses were nondetectable. In a few cases, rod involvement was also evident, with a mild reduction of amplitudes. Optical coherence tomography (OCT) imaging showed irregularity of the ellipsoid zone in the foveal area in some patients. CONCLUSIONS: is the most common cause of ACHM in patients of European descent; this is mainly due to a panethnic founder mutation, c.1148del. Here, we report on an intronic variant that is more frequent than the c.1148del mutation in our cohort of Jewish patients. Among our ACHM cohort, 63.7% of patients had biallelic mutations and 26.4% had biallelic mutations. The phenotype of patients harboring the intronic mutation falls largely within the spectrum commonly seen in ACHM. Since gene therapy for is currently under investigation, these patients might benefit from this promising therapy. Given that this variant is not detectable by current commonly used genetic testing platforms, these patients could easily be missed.
Novel mutations of the , , and genes cause abnormal development of the iris in Vietnamese individuals.
Nguyen HH, Pham CM, Nguyen HTT … +6 more , Vu NP, Duong TT, Nguyen TD, Nguyen BD, Nguyen HV, Nong HV
Mol Vis · 2021 · PMID 34566401
PURPOSE: Congenital iris abnormality is a feature of several genetic conditions, such as aniridia syndrome and anterior segment degeneration (ASD) disorders. Aniridia syndrome is caused by mutations in the gene or its r...
PURPOSE: Congenital iris abnormality is a feature of several genetic conditions, such as aniridia syndrome and anterior segment degeneration (ASD) disorders. Aniridia syndrome is caused by mutations in the gene or its regulatory elements in the locus 11p13 or deletions of contiguous genes, while ASDs are the result of mutations in various genes, such as , , , and . This study aims to identify pathogenic mutations in Vietnamese individuals with congenital anomalies of the iris. METHODS: Genomic DNA was extracted from peripheral blood of 24 patients belonging to 15 unrelated families and their available family members. Multiplex ligation-dependent probe amplification (MLPA) was used to detect the deletions or duplications in the 11p13-14 region, including the gene and its neighboring genes. Direct PCR sequencing was used to screen mutations in 13 exons and flanking sequences of the gene. The patients without mutation in the locus were further analyzed with whole exome sequencing (WES). Identified mutations were tested with segregation analysis in proband family members. RESULTS: We identified a total of 8 novel and 4 recurrent mutations in 20 of 24 affected individuals from 12 families. Among these mutations, one large deletion of the whole gene and another deletion of the downstream region containing the and genes were identified. Eight mutations were detected in , including four nonsense, three frameshift, and one splice site. In addition, two point mutations were identified in the and genes in patients without mutation in . Some of the mutations segregated in an autosomal dominant pattern where family members were available. CONCLUSIONS: This study provides new data on causative mutations in individuals with abnormal development of iris tissue in Vietnam. These results contribute to clinical management and genetic counseling for affected people and their families.
Outcome and genetic analysis of patients affected by retinal capillary hemangioblastoma in von Hippel Lindau syndrome.
Murro V, Lippera M, Mucciolo DP … +8 more , Canu L, Ercolino T, De Filpo G, Giorgio D, Traficante G, Sodi A, Virgili G, Giansanti F
Mol Vis · 2021 · PMID 34566400
PURPOSE: To describe genetic analysis, treatment results, and complications of patients affected by retinal capillary hemangioblastoma (RCH) in von Hippel Lindau (VHL) syndrome. METHODS: We collected 17 patients with VHL...
PURPOSE: To describe genetic analysis, treatment results, and complications of patients affected by retinal capillary hemangioblastoma (RCH) in von Hippel Lindau (VHL) syndrome. METHODS: We collected 17 patients with VHL syndrome, who underwent a molecular test and an ophthalmic evaluation at the Eye Clinic of the University Hospital of Florence from January 2005 to February 2020. We focused on eyes showing RCHs examined using color fundus photographs, fluorescein angiography, and optical coherence tomography. RESULTS: Eight eyes of six patients (6/17; 35%) showed RCHs at the fundoscopic examination. All RCHs were treated with laser therapy. Three eyes underwent episcleral surgery, one eye showing vitreous hemorrhage received three intravitreal (IV) anti-VEGF injections and three cryotherapy procedures, and one eye underwent vitrectomy. In patients with RCHs, five were characterized by a truncating mutation of the VHL protein, and one patient showed a missense mutation. We have reported two VHL mutations not reported in literature. CONCLUSIONS: Patients with multiple RCHs, who developed RCH secondary effects, showed truncating mutations of the VHL protein. We recommend early screening and close monitoring, especially if RCHs are detected at presentation, for every patient with VHL syndrome independently of the results of the molecular test for a missense or a truncating mutation in .
Chemerin promotes microangiopathy in diabetic retinopathy via activation of ChemR23 in rat primary microvascular endothelial cells.
Jun L, Lin-Lin S, Hui S
Mol Vis · 2021 · PMID 34531648
PURPOSE: The correlation between chemerin and diabetic retinopathy (DR) has been demonstrated previously. We aimed to investigate the potential inflammatory and angiogenic roles of chemerin in DR using rat primary retina...
PURPOSE: The correlation between chemerin and diabetic retinopathy (DR) has been demonstrated previously. We aimed to investigate the potential inflammatory and angiogenic roles of chemerin in DR using rat primary retinal microvascular endothelial cells (RRMECs). METHODS: RRMECs were incubated in low- and high-glucose media, and stable chemerin receptor (ChemR23) knockdown in RRMECs was established by lentiviral infection. Real-time quantitative PCR (RT-qPCR), enzyme-linked immunosorbent assay (ELISA), and western blotting were employed to investigate the mRNA and protein expression of intercellular adhesion molecule-1 (ICAM-1), vascular endothelial growth factor (VEGF), tumor necrosis factor-α (TNF-α), and the interleukin-6 receptor (IL-6R) to explore the inflammatory and angiogenic effects of chemerin. A scratch assay was employed to evaluate the effect of chemerin on RRMEC migration. RESULTS: Chemerin and TNF-α markedly increased the mRNA and protein expression of ICAM-1 in RRMECs (p<0.001). ChemR23 knockdown may have decreased the ICAM-1 expression under low- and high-glucose conditions (p<0.001). Even in the ChemR23-knockdown group, TNF-α significantly increased the mRNA and protein levels of ICAM-1 under low- and high-glucose conditions (p<0.001). Chemerin promoted VEGF expression under low- and high-glucose conditions. ChemR23 knockdown markedly decreased VEGF levels under low- and high-glucose conditions (p<0.05) and significantly decreased RRMEC migration (p<0.001). CONCLUSIONS: Chemerin promotes the expression of ICAM-1, the secretion of VEGF, and the migration of RRMECs via the activation of ChemR23.
Elevated histamine levels in aqueous humor of patients with glaucoma.
Gowtham L, Halder N, Angmo D … +4 more , Singh SB, Jayasundar R, Dada T, Velpandian T
Mol Vis · 2021 · PMID 34531647
PURPOSE: Neurotransmitters (NTs) are the key mediators of essential ocular functions, such as processing the visual functions of the retina, maintaining homeostasis of aqueous humor, and regulating ocular blood flow. Thi...
PURPOSE: Neurotransmitters (NTs) are the key mediators of essential ocular functions, such as processing the visual functions of the retina, maintaining homeostasis of aqueous humor, and regulating ocular blood flow. This study aims to determine variations in the levels of L-glutamate and γ-aminobutyric acid (GABA), histaminergic, adrenergic, cholinergic, and serotonergic NTs in patients with primary glaucoma versus patients with cataract. METHODS: This case-control study involved three age-matched groups of patients with primary open angle glaucoma (POAG, n = 14), primary angle closure glaucoma (PACG, n = 21), and cataract (control, n = 19). Patients' aqueous humor and plasma were collected, snap frozen at -80 °C, and subjected to ultrasensitive liquid chromatography tandem mass spectrometry (LC-MS/MS) analysis for quantification of NTs. RESULTS: Baseline intraocular pressure and the cup-to-disc ratio were found to be statistically significantly elevated in the POAG and PACG groups compared to the cataract control group. In aqueous humor, histamine was found to be statistically significantly elevated (5-fold, p<0.0001), whereas 1-methyl histamine was statistically significantly decreased (p<0.05) in POAG compared to the control group. A statistically significant increase in L-glutamate and GABA was observed among both patient groups with glaucoma compared to the cataract control group. Adrenaline was found to be elevated only in the PACG group (2.7-fold, p<0.05). No statistically significant difference was observed among the plasma NT levels between the groups. CONCLUSIONS: This study demonstrated the prominent role of the histaminergic system apart from autonomic mechanisms in the progression of glaucoma. Elevated L-glutamate and GABA could be due to retinal ganglionic cell death. Further studies are required to evaluate the effects of histamine on Müller cell dysfunction.
Identification of a novel mutation in with functional analysis in a cohort of 516 familial patients with exudative vitreoretinopathy.
Wang K, Zhang X, Tian T … +1 more , Zhao P
Mol Vis · 2021 · PMID 34526760
PURPOSE: To identify a novel mutation in with clinical and functional analysis among 516 familial patients with exudative vitreoretinopathy (FEVR). METHODS: Next-generation sequencing was performed on 516 patients with...
PURPOSE: To identify a novel mutation in with clinical and functional analysis among 516 familial patients with exudative vitreoretinopathy (FEVR). METHODS: Next-generation sequencing was performed on 516 patients with FEVR between January 2015 and October 2017. Clinical data were collected from patient charts, including sex, age at presentation, visual acuity if available, axial length, stage, and systemic clinical findings. Protein and mRNA levels were detected with western blotting and real-time quantitative PCR, respectively. Mass spectrometry was used to analyze the interacting protein of KIF11. RESULTS: In total, 304 of 516 patients were identified with at least one mutation in FEVR causative genes. Mutations in were identified in 14.47% of all carriers. The novel mutation p. H718L accounted for the greatest proportion (12/44; 27.30%) among all mutations in . Fundus presentations in these 12 individuals varied from the avascular zone of the peripheral retina to total retinal detachment. The p. H718L mutation can reduce the proliferation of human retinal endothelial cells (HRECs) compared to the wild type. The mRNA level of vascular endothelial growth factor-α, transforming growth factor-α, metalloproteinase-1, and angiopoietin-like 4 were depressed in the (p. H718L) groups under hypoxia stimuli. Mass spectrometry results demonstrated that eukaryotic elongation factor 2 (EEF2) was an interacting protein of KIF11 and that the p. H718L mutation can attenuate the binding activity. CONCLUSIONS: Patients with the most frequent mutation p. H718L showed typical FEVR presentations in this cohort. The mutation in likely plays a role in the proliferation of HRECs, and the p. H718L mutation can reduce the proliferation.
A novel duplication involving in a Turkish family supports its role in North Carolina macular dystrophy (NCMD/MCDR1).
Small KW, Van de Sompele S, Nuytemans K … +11 more , Vincent A, Yuregir OO, Ciloglu E, Sariyildiz C, Rosseel T, Avetisjan J, Udar N, Vance JM, Pericak-Vance MA, De Baere E, Shaya FS
Mol Vis · 2021 · PMID 34526759
PURPOSE: To clinically and molecularly investigate a new family with North Carolina macular dystrophy (NCMD) from Turkey, a previously unreported geographic origin for this phenotype. METHODS: Clinical ophthalmic examina...
PURPOSE: To clinically and molecularly investigate a new family with North Carolina macular dystrophy (NCMD) from Turkey, a previously unreported geographic origin for this phenotype. METHODS: Clinical ophthalmic examinations, including fundus imaging and spectral domain-optical coherence tomography (SD-OCT), were performed on eight members of a two-generation non-consanguineous family from southern Turkey. Whole genome sequencing (WGS) was performed on two affected subjects, followed by variant filtering and copy number variant (CNV) analysis. Junction PCR and Sanger sequencing were used to confirm and characterize the duplication involving at the nucleotide level. The underlying mechanism was assessed with in silico analyses. RESULTS: The proband presented with lifelong bilateral vision impairment and displayed large grade 3 coloboma-like central macular lesions. Five of her six children showed similar macular malformations, consistent with autosomal dominant NCMD. The severity grades in the six affected individuals from two generations are not evenly distributed. CNV analysis of WGS data of the two affected family members, followed by junction PCR and Sanger sequencing, revealed a novel 56.2 kb tandem duplication involving (chr6:99560265-99616492dup, hg38) at the locus. This duplication cosegregates with the NCMD phenotype in the five affected children. No other (likely) pathogenic variants in known inherited retinal disease genes were found in the WGS data. Bioinformatics analyses of the breakpoints suggest a replicative-based repair mechanism underlying the duplication. CONCLUSIONS: We report a novel tandem duplication involving the gene in a family with NCMD from a previously unreported geographic region. The duplication size is the smallest that has been reported thus far and may correlate with the particular phenotype.
Review: Cytoplasmic dynein motors in photoreceptors.
Dahl TM, Baehr W
Mol Vis · 2021 · PMID 34526758
Cytoplasmic dyneins (dynein-1 and dynein-2) transport cargo toward the minus end of microtubules and thus, are termed the "retrograde" cellular motor. Dynein-1 cargo may include nuclei, mitochondria, membrane vesicles, l...
Cytoplasmic dyneins (dynein-1 and dynein-2) transport cargo toward the minus end of microtubules and thus, are termed the "retrograde" cellular motor. Dynein-1 cargo may include nuclei, mitochondria, membrane vesicles, lysosomes, phagosomes, and other organelles. For example, dynein-1 works in the cell body of eukaryotes to move cargo toward the microtubule minus end and positions the Golgi complex. Dynein-1 also participates in the movement of chromosomes and the positioning of mitotic spindles during cell division. In contrast, dynein-2 is present almost exclusively within cilia where it participates in retrograde intraflagellar transport (IFT) along the axoneme to return kinesin-2 subunits, BBSome, and IFT particles to the cell body. Cytoplasmic dyneins are hefty 1.5 MDa complexes comprised of dimers of heavy, intermediate, light intermediate, and light chains. Missense mutations of human are associated with malformations of cortical development (MCD) or spinal muscular atrophy with lower extremity predominance (SMA-LED). Missense mutations in are causative of short-rib polydactyly syndrome type III and nonsyndromic retinitis pigmentosa. We review mutations of the two dynein heavy chains and their effect on postnatal retina development and discuss consequences of deletion of in the mouse retina.
Comparative proteome analysis of form-deprivation myopia in sclera with iTRAQ-based quantitative proteomics.
Yuan Y, Zhu C, Liu M … +1 more , Ke B
Mol Vis · 2021 · PMID 34526757
OBJECTIVE: Scleral remodeling plays a key role in axial elongation in myopia. The aim of the present study was to identify the proteomics changes and specific signaling networks to gain insight into the molecular basis o...
OBJECTIVE: Scleral remodeling plays a key role in axial elongation in myopia. The aim of the present study was to identify the proteomics changes and specific signaling networks to gain insight into the molecular basis of scleral remodeling in myopic eyes. METHODS: Guinea pig form-deprivation myopia was induced with a translucent diffuser on a random eye for 4 weeks, while the other eye served as the contralateral control group. The axial length and refraction were measured at the beginning and end of the treatment. The proteins were extracted from the sclerae of each group and prepared for quantitative isobaric tags for relative and absolute quantification (iTRAQ) labeling combined with liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis. The coexpression networks and protein functions were analyzed using Gene Ontology (GO) and Ingenuity Pathway Analysis (IPA). Quantitative real-time PCR (qRT-PCR) and western blotting were performed to confirm the authenticity and accuracy of the iTRAQ results. RESULTS: After 4 weeks, the form-deprivation eyes developed significant degrees of myopia, and the axial length increased statistically significantly (p<0.05). A total of 2,579 unique proteins with <1% false discovery rate (FDR) were identified. Furthermore, 56 proteins were found to be upregulated, and 84 proteins were found to be downregulated, with a threshold of a 1.2-fold change and p<0.05 in the myopia group, when compared to the control group. Further bioinformatics analysis indicated that 44 of 140 differentially expressed proteins were involved in cellular movement and cellular assembly and organization. The qRT-PCR or western blotting results confirmed that myosin IIB, ACTIN3, and cellular cytoskeletons were downregulated, while RhoA and RAP1A were upregulated in the sclera in myopic eyes. These results were consistent with the proteomics results. CONCLUSIONS: Proteomics and bioinformatics results can be helpful for identifying proteins and providing new insights for better understanding of the molecular mechanism underlying scleral remodeling. These results revealed that the proteins associated with cellular movement and cellular assembly and organization are altered during the development of myopia. Furthermore, RhoA plays a key role in the pathways involved in cellular movement and cellular assembly and organization.
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