RESUMEN
Retinitis pigmentosa (RP) is a heterogeneous inherited retinal disorder. Mutations in KIZ cause autosomal recessive (AR) RP. We aimed to characterize the genotype, expression pattern, and phenotype in a large cohort of KIZ cases. Sanger and whole exome sequencing were used to identify the KIZ variants. Medical records were reviewed and analyzed. Thirty-one patients with biallelic KIZ mutations were identified: 28 homozygous for c.226C>T (p.R76*), 2 compound heterozygous for p.R76* and c.3G>A (p.M1?), and one homozygous for c.247C>T (p.R83*). c.226C>T is a founder mutation among patients of Jewish descent. The clinical parameters were less severe in KIZ compared to DHDDS and FAM161A cases. RT-PCR analysis in fibroblast cells revealed the presence of four different transcripts in both WT and mutant samples with a lower percentage of the WT transcript in patients. Sequence analysis identified an exonic sequence enhancer (ESE) that includes the c.226 position which is affected by the mutation. KIZ mutations are an uncommon cause of IRD worldwide but are not rare among Ashkenazi Jews. Our data indicate that p.R76* affect an ESE which in turn results in the pronounced skipping of exon 3. Therefore, RNA-based therapies might show low efficacy since the mutant transcripts are spliced.
Asunto(s)
Mutación , Retinitis Pigmentosa , Adolescente , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Secuenciación del Exoma/métodos , Proteínas del Ojo/genética , Judíos/genética , Linaje , Fenotipo , Retinitis Pigmentosa/genética , Retinitis Pigmentosa/patologíaRESUMEN
Importance: Data regarding the prevalence of various inherited retinal diseases (IRDs) are limited and vary across populations; moreover, nationwide prevalence studies may be limited to a specific IRD phenotype, potentially leading to inaccurate prevalence estimations. Therefore, nationwide prevalence data are needed. Objective: To determine the prevalence of 67 IRD phenotypes in the Israeli population. Design, Setting, and Participants: This cohort study collected nationwide data regarding the number of individuals affected with IRD phenotypes assessed in 10 clinical and academic centers in Israel as part of the research activity of the Israeli inherited retinal disease consortium. Data were collected in May 2023 on 9396 individuals residing in Israel who were diagnosed by an ophthalmologist with an IRD using either electroretinography or retinal imaging where included. Individuals with retinal diseases known to have a nonmendelian basis or without a clear genetic basis and those who were reported as deceased at the time of data collection were excluded from this study. Main Outcomes and Measures: Prevalence of 67 IRD phenotypes. Results: Among the 9396 participants in our cohort, the most common IRD in Israel was retinitis pigmentosa with a disease prevalence of approximately 1:2400 individuals, followed by cone-rod dystrophy (approximately 1:14â¯000), Stargardt disease (approximately 1:16â¯000), Usher syndrome (approximately 1:16,000), and congenital stationary night blindness (approximately 1:18â¯000). The prevalence of all IRDs combined was 1:1043 individuals. Conclusions and Relevance: The current study provides large prevalence dataset of 67 IRD phenotypes, some of which are extremely rare, with only a single identified case. This analysis highlights the potential importance of performing additional nationwide prevalence studies to potentially assist with determining the prevalence of IRDs worldwide.
Asunto(s)
Electrorretinografía , Enfermedades de la Retina , Humanos , Israel/epidemiología , Prevalencia , Masculino , Femenino , Adulto , Enfermedades de la Retina/epidemiología , Enfermedades de la Retina/genética , Enfermedades de la Retina/diagnóstico , Persona de Mediana Edad , Fenotipo , Adolescente , Adulto Joven , Anciano , Niño , Enfermedades Hereditarias del Ojo/epidemiología , Enfermedades Hereditarias del Ojo/genética , PreescolarRESUMEN
Amyloid-beta (Aß), a family of aggregation-prone and neurotoxic peptides, has been implicated in the pathophysiology of age-related macular degeneration (AMD). We have previously shown that oligomeric and fibrillar species of Aß42 exerted retinal toxicity in rats, but while the consequences of exposure to amyloid were related to intracellular effects, the mechanism of Aß42 internalization in the retina is not well characterized. In the brain, the 67 kDa laminin receptor (67LR) participates in Aß-related neuronal cell death. A short peptide derived from pigment epithelium-derived factor (PEDF), formerly designated PEDF-335, was found to mitigate experimental models of ischemic retinopathy via targeting of 67LR. In the present study, we hypothesized that 67LR mediates the uptake of pathogenic Aß42 assemblies in the retina, and that targeting of this receptor by PEDF-335 may limit the internalization of Aß, thereby ameliorating its retinotoxicity. To test this assumption ARPE-19 cells in culture were incubated with PEDF-335 before treatment with fibrillar or oligomeric structures of Aß42. Immunostaining confirmed that PEDF-335 treatment substantially prevented amyloid internalization into ARPE-19 cells and maintained their viability in the presence of toxic oligomeric and fibrillar Aß42 entities in vitro. FRET competition assay was performed and confirmed the binding of PEDF-335 to 67LR in RPE-like cells. Wild-type rats were treated with intravitreal PEDF-335 in the experimental eye 2 days prior to administration of retinotoxic Aß42 oligomers or fibrils to both eyes. Retinal function was assessed by electroretinography through 6 weeks post injection. The ERG responses in rats treated with oligomeric or fibrillar Aß42 assemblies were near-normal in eyes previously treated with intravitreal PEDF-335, whereas those measured in the control eyes treated with injection of the Aß42 assemblies alone showed pathologic attenuation of the retinal function through 6 weeks. The retinal presence of 67LR was determined ex vivo by immunostaining and western blotting. Retinal staining demonstrated the constitutional expression of 67LR mainly in the retinal nuclear layers. In the presence of Aß42, the levels of 67LR were increased, although its retinal distribution remained largely unaltered. In contrast, no apparent differences in the retinal expression level of 67LR were noted following exposure to PEDF-335 alone, and its pattern of localization in the retina remained similarly concentrated primarily in the inner and outer nuclear layers. In summary, we found that PEDF-335 confers protection against Aß42-mediated retinal toxicity, with significant effects noted in cells as well as in vivo in rats. The effects of PEDF-335 in the retina are potentially mediated via binding to 67LR and by at least partial inhibition of Aß42 internalization. These results suggest that PEDF-335 may merit further consideration in the development of targeted inhibition of amyloid-related toxicity in the retina. More broadly, our observations provide evidence on the importance of extracellular versus intracellular Aß42 in the retina and suggest concepts on the molecular mechanism of Aß retinal pathogenicity.
Asunto(s)
Péptidos beta-Amiloides , Electrorretinografía , Proteínas del Ojo , Factores de Crecimiento Nervioso , Serpinas , Animales , Serpinas/metabolismo , Proteínas del Ojo/metabolismo , Factores de Crecimiento Nervioso/metabolismo , Ratas , Péptidos beta-Amiloides/toxicidad , Péptidos beta-Amiloides/metabolismo , Epitelio Pigmentado de la Retina/efectos de los fármacos , Epitelio Pigmentado de la Retina/metabolismo , Fragmentos de Péptidos/toxicidad , Modelos Animales de Enfermedad , Receptores de Laminina/metabolismo , Masculino , Retina/efectos de los fármacos , Retina/metabolismo , Humanos , Inyecciones Intravítreas , Western Blotting , Enfermedades de la Retina/prevención & control , Enfermedades de la Retina/metabolismo , Enfermedades de la Retina/inducido químicamente , Células CultivadasRESUMEN
Age-related macular degeneration (AMD) is a complex disease in which inflammation is implicated as a key factor but the precise molecular mechanisms are poorly understood. AMD lesions contain an excess of the pro-inflammatory S100A9 protein, but its retinal significance was yet unexplored. S100A9 was shown to be intrinsically amyloidogenic in vitro and in vivo. Here, we hypothesized that the retinal effects of S100A9 are related to its supramolecular conformation. ARPE-19 cultures were treated with native dimeric and fibrillar S100A9 preparations, and cell viability was determined. Wild-type rats were treated intravitreally with the S100A9 solutions in the right eye and with the vehicle in the left. Retinal function was assessed longitudinally by electroretinography (ERG), comparing the amplitudes and configurations for each intervention. Native S100A9 had no impact on cellular viability in vitro or on the retinal function in vivo. Despite dispersed intracellular uptake, fibrillar S100A9 did not decrease ARPE-19 cell viability. In contrast, S100A9 fibrils impaired retinal function in vivo following intravitreal injection in rats. Intriguingly, low-dose fibrillar S100A9 induced contrasting in vivo effects, significantly increasing the ERG responses, particularly over 14 days postinjection. The retinal effects of S100A9 were further characterized by glial and microglial cell activation. We provide the first indication for the retinal effects of S100A9, showing that its fibrils inflicted retinal dysfunction and glial activation in vivo, while low dose of the same assemblies resulted in an unpredicted enhancement of the ERG amplitudes. These nonlinear responses highlight the consequences of self-assembly of S100A9 and provide insight into its pathophysiological and possibly physiological roles in the retina.
Asunto(s)
Calgranulina B , Degeneración Macular , Ratas , Animales , Calgranulina B/metabolismo , Retina/metabolismo , Degeneración Macular/tratamiento farmacológico , Degeneración Macular/metabolismo , Electrorretinografía , Inflamación/metabolismo , Modelos Animales de EnfermedadRESUMEN
- Objective: To explore the clinical validity of elastic deformation of optical coherence tomography (OCT) images for data augmentation in the development of deep-learning model for detection of diabetic macular edema (DME). METHODS: Prospective evaluation of OCT images of DME (n = 320) subject to elastic transformation, with the deformation intensity represented by ([Formula: see text]). Three sets of images, each comprising 100 pairs of scans (100 original & 100 modified), were grouped according to the range of ([Formula: see text]), including low-, medium- and high-degree of augmentation; ([Formula: see text] = 1-6), ([Formula: see text] = 7-12), and ([Formula: see text] = 13-18), respectively. Three retina specialists evaluated all datasets in a blinded manner and designated each image as 'original' versus 'modified'. The rate of assignment of 'original' value to modified images (false-negative) was determined for each grader in each dataset. RESULTS: The false-negative rates ranged between 71-77% for the low-, 63-76% for the medium-, and 50-75% for the high-augmentation categories. The corresponding rates of correct identification of original images ranged between 75-85% ([Formula: see text]0.05) in the low-, 73-85% ([Formula: see text]0.05 for graders 1 & 2, p = 0.01 for grader 3) in the medium-, and 81-91% ([Formula: see text]) in the high-augmentation categories. In the subcategory ([Formula: see text] = 7-9) the false-negative rates were 93-83%, whereas the rates of correctly identifying original images ranged between 89-99% ([Formula: see text]0.05 for all graders). CONCLUSIONS: Deformation of low-medium intensity ([Formula: see text] = 1-9) may be applied without compromising OCT image representativeness in DME. Clinical and Translational Impact Statement-Elastic deformation may efficiently augment the size, robustness, and diversity of training datasets without altering their clinical value, enhancing the development of high-accuracy algorithms for automated interpretation of OCT images.
Asunto(s)
Aprendizaje Profundo , Diabetes Mellitus , Retinopatía Diabética , Edema Macular , Humanos , Edema Macular/diagnóstico por imagen , Retinopatía Diabética/diagnóstico , Tomografía de Coherencia Óptica/métodos , RetinaRESUMEN
PURPOSE: To establish the clinical necessity of routine targeted ophthalmic examination of newborns with congenital cytomegalovirus (CMV) infection during the neonatal period. METHODS: This retrospective study included consecutive neonates that were referred for ophthalmological screening within the context of a proven congenital CMV infection. The presence of CMV-related ocular and systemic findings was determined. RESULTS: Among the 91 patients included in this study, 72 (79.12%) were symptomatic with one or more of the following manifestations: abnormal brain ultrasound (42; 46.15%), small for gestational age (29; 31.87%), microcephaly (23; 25.27%), thrombocytopenia (14; 15.38%), sensory neural hearing loss (13; 14.29%), neutropenia (12; 13.19%), anemia (4; 4.4%), skin lesions (4; 4.4%), hepatomegaly (3; 3.3%), splenomegaly (3; 3.3%), direct hyperbilirubinemia (2; 2.2%). Not one single neonate in this cohort had any of the ocular findings surveyed. CONCLUSION: The presence of ophthalmological findings among neonates with congenital CMV infection during the neonatal period is infrequent, suggesting that routine ophthalmological screening may be safely deferred for the post-neonatal period.
Asunto(s)
Infecciones por Citomegalovirus , Citomegalovirus , Humanos , Recién Nacido , Estudios Retrospectivos , Infecciones por Citomegalovirus/diagnóstico , Encéfalo , OjoRESUMEN
Purpose: To describe ocular findings in individuals with primary hyperoxaluria type 1 (PH1), focusing on the correlations between retinal anatomy and retinal function. To characterize the retinal alterations that occur at different disease stages by evaluating individuals with diverse degrees of renal impairment associated with PH1. Design: A cross-sectional study. Participants: Patients diagnosed with PH1 based on clinical criteria and genetic testing, treated in the Pediatric Nephrology Unit of the Ruth Children's Hospital, Rambam Health Care Campus, Haifa, Israel between 2013 and 2021. Methods: The ophthalmological assessment included a slit-lamp biomicroscopy of the anterior and posterior segment or indirect ophthalmoscopy. Electroretinography was employed for assessment of the retinal function, and retinal imaging included spectral-domain OCT and fundus autofluorescence. A systematic evaluation of the disease stage was based on clinical criteria including physical examination, purposeful imaging (X-ray, echocardiography, and US abdomen), and laboratory tests as needed. Main Outcome Measures: Anatomical and functional assessment of the retina in patients with PH1, and the relationship between retinal dysfunction and kidney impairment. Results: A total of 16 eyes were examined in the study of 8 children ranging in age from 4 to 19 years. Four eyes (25%) showed normal structural and functional retinal findings, 8 eyes (50%) presented functional impairment in the absence of pathological structural findings, and 4 eyes (25%) had advanced retinal damage that manifested as significant morphological and functional impairment. There was no direct relationship between the severity of the renal disease and the severity of the retinal phenotype. Conclusions: Subjects with PH1 present varying severity levels of the retinal phenotype, with possible discrepancy between the clinical retinal morphology and the retinal function noted on electroretinography. These findings raise questions about the molecular basis of the retinal manifestations in PH1. The presence of functional impairment in the absence of evident crystal deposition in the retina suggests that, in addition to oxalate crystal accumulation, other biomolecular processes may play a role in the development of retinopathy.
RESUMEN
PURPOSE: Pseudophakic cystoid macular edema (CME) occurs in up to 2% of uneventful cataract surgeries. This study evaluates changes in macular blood flow succeeding uneventful phacoemulsification cataract extraction among otherwise visually healthy subjects. METHODS: This prospective study included 18 eyes of 18 patients undergoing routine phacoemulsification. Optical coherence tomography angiography (OCT-A) was performed using the Angio-Retina 6 × 6 mm protocol with the XR Avanti Angio-Vue system (Optovue Inc., Fremont, California) prior to the surgery and 4-8 weeks thereafter. Exclusion criteria included motion artifacts, segmentation errors and signal strength index (SSI) < 40. The main outcome measure was change in flow index (FI) measured in all 4 retinal segmentation layers within an area of 1 mm diameter around the foveal center. RESULTS: Following surgery, a significant increase in SSI (46.65 ± 8.62 versus 53.12 ± 8.07, p = 0.01), superficial plexus FI (0.98 ± 0.23 versus 1.16 ± 0.16, p = 0.02) and deep plexus FI (0.54 ± 0.46 versus 0.93 ± 0.39, p = 0.01) was found. No significant changes were noted in the outer retina or the choriocapillaris. CONCLUSION: The study demonstrates a significant increase in FI in the superficial and deep retinal plexus following uneventful cataract surgery, with the greatest changes occurring in the latter. These findings corroborate evidence from structural imaging and support the vascular etiology of pseudophakic CME.
Asunto(s)
Catarata , Edema Macular , Humanos , Tomografía de Coherencia Óptica/métodos , Estudios Prospectivos , Retina , Edema Macular/etiología , Angiografía/efectos adversos , Catarata/complicaciones , Angiografía con FluoresceínaRESUMEN
Purpose: To identify the molecular mechanisms of the development of autosomal dominant retinitis pigmentosa (adRP) with incomplete penetrance in an Israeli Muslim Arab family. Methods: Two patients with adRP underwent a detailed ophthalmic evaluation, including funduscopic examination, visual field testing, optical coherence tomography, and electroretinography. Genetic analysis was performed using a combination of whole exome sequencing (WES) and Sanger sequencing. The pathogenicity of the identified intronic variant was evaluated in silico using several web-based tools, in vitro using a minigene-based assay, and in vivo using reverse transcription PCR analysis of lymphocyte-derived RNA. The relative abundance of alternatively spliced transcripts was evaluated using amplicon-based next-generation sequencing. The relative expression levels of PRPF31 and CNOT3 were measured using quantitative PCR (qPCR) analysis. Results: The two patients recruited in this study had childhood-onset RP, with night blindness as the initial symptom, followed by concentric restriction of the visual field. The funduscopic findings included narrowed retinal blood vessels and peripheral bone spicule pigmentation. By the third decade of life, the full-field electroretinography findings had been remarkably attenuated. In these patients, we identified a novel heterozygous intronic variant at position +5 of PRPF31 intron 11 (c.1146+5G>T). The same variant was also detected in one asymptomatic family member. Through in silico analysis, the variant was predicted to alter the splicing of intron 11. An in vitro splicing assay and a reverse transcription PCR analysis of lymphocyte-derived RNA revealed that the mutant allele yielded mainly a shorter transcript in which exon 11 was skipped. The skipping of exon 11 was expected to cause a frameshift and an aberrant truncated protein (p.Tyr359Serfs*29). The qPCR analysis revealed reduced PRPF31 expression levels in the mutation carriers, without a significant difference between the affected patient and his asymptomatic brother. We evaluated several factors that have been suggested to correlate with non-penetrance of PRPF31 mutations, including the number of cis-acting MSR1 elements adjacent to the PRPF31 core promoter, CNOT3 expression level, and CNOT3 rs4806718 single-nucleotide polymorphism. None of these factors correlated with non-penetrance in the family in this study. Conclusions: We report a novel intronic mutation in PRPF31 underlying adRP. This report expands the spectrum of pathogenic mutations in PRPF31 and further demonstrates the importance of intronic mutations. Moreover, it demonstrates the phenomenon of incomplete penetrance previously associated with PRPF31 mutations. The fact that the non-penetrance in the family in this study could not be explained by any of the known mechanisms suggests the possible contribution of a novel modifier of PRPF31 penetrance.
Asunto(s)
Proteínas del Ojo , Retinitis Pigmentosa , Masculino , Humanos , Niño , Proteínas del Ojo/genética , Proteínas del Ojo/metabolismo , Linaje , Retinitis Pigmentosa/diagnóstico , Mutación/genética , ARN , Genes Dominantes , Factores de Transcripción/genéticaRESUMEN
Cell adhesion molecules are membrane-bound proteins predominantly expressed in the central nervous system along principal axonal pathways with key roles in nervous system development, neural cell differentiation and migration, axonal growth and guidance, myelination, and synapse formation. Here, we describe ten affected individuals with bi-allelic variants in the neuronal cell adhesion molecule NRCAM that lead to a neurodevelopmental syndrome of varying severity; the individuals are from eight families. This syndrome is characterized by developmental delay/intellectual disability, hypotonia, peripheral neuropathy, and/or spasticity. Computational analyses of NRCAM variants, many of which cluster in the third fibronectin type III (Fn-III) domain, strongly suggest a deleterious effect on NRCAM structure and function, including possible disruption of its interactions with other proteins. These findings are corroborated by previous in vitro studies of murine Nrcam-deficient cells, revealing abnormal neurite outgrowth, synaptogenesis, and formation of nodes of Ranvier on myelinated axons. Our studies on zebrafish nrcamaΔ mutants lacking the third Fn-III domain revealed that mutant larvae displayed significantly altered swimming behavior compared to wild-type larvae (p < 0.03). Moreover, nrcamaΔ mutants displayed a trend toward increased amounts of α-tubulin fibers in the dorsal telencephalon, demonstrating an alteration in white matter tracts and projections. Taken together, our study provides evidence that NRCAM disruption causes a variable form of a neurodevelopmental disorder and broadens the knowledge on the growing role of the cell adhesion molecule family in the nervous system.
Asunto(s)
Trastornos del Neurodesarrollo , Enfermedades del Sistema Nervioso Periférico , Animales , Axones/metabolismo , Adhesión Celular/genética , Moléculas de Adhesión Celular/genética , Moléculas de Adhesión Celular/metabolismo , Moléculas de Adhesión Celular Neuronal , Humanos , Ratones , Hipotonía Muscular/genética , Hipotonía Muscular/metabolismo , Espasticidad Muscular/metabolismo , Trastornos del Neurodesarrollo/genética , Trastornos del Neurodesarrollo/metabolismo , Pez Cebra/genética , Pez Cebra/metabolismoRESUMEN
BACKGROUND AND OBJECTIVE: Determine the ability of Lambda retinometry to predict post-cataract surgery visual acuity in vitrectomized eyes. PATIENTS AND METHODS: Prospective study including 47 cataract surgery candidates with a history of pars plana vitrectomy (PPV). Lambda retinometry using a hand-held Lambda retinometer and best-corrected visual acuity (BCVA) were measured preoperatively, and BCVA was reassessed postoperatively. RESULTS: Lambda predictions strongly correlated with postoperative BCVA (logarithm of the minimum angle of resolution [logMAR]) (P < .001, r2 = 0.57), especially combined with preoperative BCVA (logMAR) (P < .001, r2 = 0.65). In 89% of cases, postoperative BCVA was equal to or higher than the prediction. Neither cataract grades nor indications for PPV were associated with the accuracy of Lambda predictions (P = .882 and P = .790, respectively). Underestimation of visual outcome was more common than overestimation. A Lambda prediction of ≥ 20/40 (Snellen) had a positive predictive value of 85.7% and a negative predictive value of 73.6% for the postoperative outcome. CONCLUSIONS: Lambda retinometry can reliably predict the postoperative BCVA in cataract patients who previously underwent PPV, with a tendency towards underestimation. [Ophthalmic Surg Lasers Imaging Retina. 2021;52:535-542.].
Asunto(s)
Extracción de Catarata , Catarata , Catarata/complicaciones , Catarata/diagnóstico , Humanos , Estudios Prospectivos , Agudeza Visual , VitrectomíaRESUMEN
PURPOSE: To identify risk factors for incorrect self-identification of the treatment eye before intravitreal injections. METHODS: This prospective study included consecutive patients who were asked to designate the eye for which the intravitreal injection was intended and were subsequently divided into two groups according to whether or not they identified the correct eye. RESULTS: Overall, 349 eyes (n = 349) were included, and 8.6% (n = 30) designated the incorrect eye or did not know which eye was intended for treatment. Incorrect designation was associated with diabetic macular edema (odds ratio [OR] = 0.33 [0.15-0.75]), first injection in the intended eye or ≥1 year since previous injection (OR = 0.34 [0.14-0.87]), Arabic native tongue (OR = 0.48 [0.22-1.01]), previous injection to the fellow eye (OR = 0.26 [0.10-0.64]), and concurrent treatment of both eyes (OR = 0.35 [0.16-0.74]). Multivariate analysis showed the first injection or ≥1 year since last injection in the treatment eye (R2 = 2.24%, P = 0.004, OR = 0.20 [0.07-0.57]) and previous injection in the fellow eye (R2 = 6.55%, P < 0.001, OR = 0.20 [0.07-0.52]) as significant independent predictors of incorrect identification. CONCLUSION: Several factors are associated with a greater probability for incorrect patient's self-identification of the eye laterality intended for intravitreal injections. These findings may help identify patients with a higher risk of such potential errors.
Asunto(s)
Bevacizumab/administración & dosificación , Retinopatía Diabética/tratamiento farmacológico , Edema Macular/tratamiento farmacológico , Errores Médicos/estadística & datos numéricos , Medición de Riesgo/métodos , Adulto , Anciano , Anciano de 80 o más Años , Inhibidores de la Angiogénesis/administración & dosificación , Estudios de Casos y Controles , Retinopatía Diabética/complicaciones , Retinopatía Diabética/diagnóstico , Femenino , Estudios de Seguimiento , Humanos , Inyecciones Intravítreas/métodos , Israel/epidemiología , Edema Macular/diagnóstico , Edema Macular/etiología , Masculino , Persona de Mediana Edad , Prevalencia , Estudios Prospectivos , Factores de Riesgo , Tomografía de Coherencia Óptica/métodos , Factor A de Crecimiento Endotelial Vascular/antagonistas & inhibidores , Agudeza VisualRESUMEN
γD-crystallin is among the most abundant γ-crystallins in the human eye lens which are essential for preserving its transparency. Aging, and environmental changes, cause crystallins to lose their native soluble structure and aggregate, resulting in the formation of cataract. Current treatment of cataract is surgical removal which is costly. Pharmaceutical therapeutics of cataract is an unmet need. We report a screen for small molecules capable of inhibiting aggregation of human γD-crystallin. Using a highly amyloidogenic hexapeptide model 41GCWMLY46 derived from the full-length protein, we screened a library of 68 anthraquinone molecules using ThT fluorescence assay. A leading hit, the cochineal Carmine, effectively reduced aggregation of the model GDC6 peptide in dose dependent manner. Similar effect was observed toward aggregation of the full-length γD-crystallin. Transmission electron microscopy, intrinsic Tryptophan fluorescence and ANS fluorescence assays corroborated these results. Insights obtained from molecular docking suggested that Carmine interaction with monomeric GDC6 involved hydrogen bonding with Ace group, Cys, Met residues and hydrophobic contact with Trp residue. Carmine was non-toxic toward retinal cells in culture. It also reduced ex vivo the turbidity of human extracted cataract material. Collectively, our results indicate that Carmine could be used for developing new therapeutics to treat cataract.
Asunto(s)
Amiloide/metabolismo , Carmín/farmacología , gamma-Cristalinas/metabolismo , Proteínas Amiloidogénicas/metabolismo , Carmín/metabolismo , Catarata/metabolismo , Línea Celular , Humanos , Cristalino/metabolismo , Modelos Moleculares , Simulación del Acoplamiento Molecular , Péptidos/metabolismo , Agregado de Proteínas/efectos de los fármacos , Epitelio Pigmentado de la Retina/efectos de los fármacos , Epitelio Pigmentado de la Retina/metabolismo , gamma-Cristalinas/químicaRESUMEN
Amyloid-ß (Aß), reported as a significant constituent of drusen, was implicated in the pathophysiology of age-related macular degeneration (AMD), yet the identity of the major pathogenic Aß species in the retina has remained hitherto unclear. Here, we examined the in-vivo retinal impact of distinct supramolecular assemblies of Aß. Fibrillar (Aß40, Aß42) and oligomeric (Aß42) preparations showed clear biophysical hallmarks of amyloid assemblies. Measures of retinal structure and function were studied longitudinally following intravitreal administration of the various Aß assemblies in rats. Electroretinography (ERG) delineated differential retinal neurotoxicity of Aß species. Oligomeric Aß42 inflicted the major toxic effect, exerting diminished ERG responses through 30 days post injection. A lesser degree of retinal dysfunction was noted following treatment with fibrillar Aß42, whereas no retinal compromise was recorded in response to Aß40 fibrils. The toxic effect of Aß42 architectures was further reflected by retinal glial response. Fluorescence labelling of Aß42 species was used to detect their accumulation into the retinal tissue. These results provide conceptual evidence of the differential toxicity of particular Aß species in-vivo, and promote the mechanistic understanding of their retinal pathogenicity. Stratifying the impact of pathological Aß aggregation in the retina may merit further investigation to decipher the pathophysiological relevance of processes of molecular self-assembly in retinal disorders.
Asunto(s)
Péptidos beta-Amiloides/toxicidad , Fenómenos Biofísicos , Multimerización de Proteína , Retina/fisiopatología , Péptidos beta-Amiloides/administración & dosificación , Animales , Electrorretinografía , Proteína Ácida Fibrilar de la Glía/metabolismo , Inyecciones Intravítreas , Multimerización de Proteína/efectos de los fármacos , Ratas Sprague-Dawley , Retina/efectos de los fármacos , Retina/patologíaRESUMEN
BACKGROUND: This study assessed the impact of contact lens wear on retinal spectral domain optical coherence tomography (SD-OCT) image quality and macular thickness measurements, among subjects with myopia. METHODS: This was a prospective study including 34 subjects (26.59 ± 3.19 years) with myopia or myopic astigmatism. Twelve were imaged wearing spherical soft contact lenses, eight non-contact lens wearers were imaged with a plano soft contact lens, and 14 with significant astigmatism were fitted with a rigid gas permeable (RGP) contact lens. For each group of contact lens types, the average image quality index (Q-index), and the average macular thickness measurements were compared between macular OCT scans obtained from the same eyes with and without a contact lens. RESULTS: Among the subjects assessed with their habitual spherical soft lenses, the average Q-index was similar for scans acquired with and without a contact lens (30.10 ± 1.94 versus 31.03 ± 2.55; p = 0.18). Among non-contact lens wearers, the average Q-index was slightly higher for scans acquired without a contact lens, compared to scans with a plano contact lens (31.99 ± 2.06 versus 29.51 ± 1.56; p = 0.006). Among 14 subjects imaged wearing a fitted RGP contact lens, the Q-index was similar for scans acquired with and without a contact lens (29.04 ± 2.73 versus 28.75 ± 2.86; p = 0.78). In all groups, there were no correlations between the power of the sphere and change in the Q-index (that is, post- minus pre-contact lens Q-index), and no differences were found between OCT-derived macular thickness measurements from scans with and without a contact lens. The magnitude of cylinder was not correlated with the change in the Q-index in the habitual and RGP contact lens groups. However, an inverse correlation between cylinder power and change in the Q-index was found in the plano contact lens group. CONCLUSION: In low to intermediate levels of myopia, with or without regular astigmatism, macular SD-OCT imaging does not merit placement of a soft or rigid contact lens, nor is there an added benefit from removing a habitual spherical soft lens prior to scanning.
Asunto(s)
Lentes de Contacto Hidrofílicos , Miopía , Humanos , Miopía/terapia , Estudios Prospectivos , Retina/diagnóstico por imagen , Tomografía de Coherencia ÓpticaRESUMEN
The formation of metabolite fibrillar assemblies represents a paradigm shift in the study of human metabolic disorders. Yet, direct clinical relevance has been attributed only to metabolite crystals. A notable example for metabolite crystallization is calcium oxalate crystals observed in various diseases, including primary hyperoxaluria. We unexpectedly observed retinal damage among young hyperoxaluria patients in the absence of crystals. Exploring the possible formation of alternative supramolecular organizations and their biological role, here we show that oxalate can form ordered fibrils with no associated calcium. These fibrils inflict intense retinal cytotoxicity in cultured cells. A rat model injected with oxalate fibrils recaptures patterns of retinal dysfunction observed in patients. Antibodies purified from hyperoxaluria patient sera recognize oxalate fibrils regardless of the presence of calcium. These findings highlight a new molecular basis for oxalate-associated disease, and to our knowledge provide the first direct clinical indication for the pathogenic role of metabolite fibrillar assemblies.
RESUMEN
Purpose: To evaluate the correlation between pain during cataract surgery and preoperative anxiety.Methods: This prospective observational masked study included 103 eyes of 103 consecutive patients who underwent routine clear corneal incision phacoemulsification surgery at the Department of Ophthalmology, Rambam Health Care Campus, Haifa, Israel. Patients were interviewed prior to surgery and 5 min following surgery by two separate independent interviewers. Anxiety level was measured by the Visual Analog Scale for Anxiety (VASA) and pain by the Visual Analog Scale (VAS). The main outcome measure was the maximum amount of pain endured during the procedure using VAS.Results: The mean participant age was 68.9 ± 8.9 years, and 46.6% were male. Severe anxiety (VASA ≥ 7) and pain (VAS ≥ 7) were documented in 18.5 and 17.5% of patients, respectively. There was a statistically significant positive correlation between VAS and VASA (r = 0.62, p < .001) as well as between VAS and duration of surgery (r = 0.20, p = .04). There was no association between VAS and all other investigated parameters in the univariate analysis. In backward regression analysis, VASA was the only parameter that was significantly associated with VAS (R2 = 36.61%, p < .001). Patients with severe anxiety were >10 times more likely to experience severe pain, and a VASA > 4 predicted severe pain with a sensitivity of 88.9% and a specificity of 69.4%.Conclusions: One-fifth of patients experienced severe anxiety and pain. Preoperative anxiety levels were the only significant predictor of pain. Reducing preoperative anxiety in cataract patients is warranted.
Asunto(s)
Ansiedad/etiología , Extracción de Catarata/efectos adversos , Complicaciones Intraoperatorias/diagnóstico , Dimensión del Dolor/métodos , Dolor/diagnóstico , Anciano , Ansiedad/epidemiología , Femenino , Estudios de Seguimiento , Humanos , Incidencia , Complicaciones Intraoperatorias/etiología , Israel/epidemiología , Masculino , Dolor/etiología , Periodo Preoperatorio , Pronóstico , Estudios ProspectivosRESUMEN
PURPOSE: To identify factors associated with persistent subretinal fluid (SRF) after small-gauge pars plana vitrectomy for primary rhegmatogenous retinal detachment. METHODS: This retrospective study included patients from 2 tertiary centers who underwent pars plana vitrectomy for repair of rhegmatogenous retinal detachment between 2013 and 2016. Preoperative and intraoperative parameters were examined for association with development of SRF. RESULTS: Overall, 153 eyes of 153 patients, mean age of 55.2 ± 17.9 years were included. Persistent SRF occurred in 15.0% (n = 23) and was associated with high myopia (65.22 vs. 26.15%, P < 0.001), macula-involving retinal detachment (91.30 vs. 66.15%, P = 0.02), phakic lens status (86.96 vs. 66.15%, P = 0.04), and younger age (47.8 ± 18.7 vs. 56.5 ± 17.5, P = 0.04) while drainage retinotomy was protective (13.04 vs. 34.11%, P = 0.04). In multivariate analysis, high myopia (P = 0.009) and macula-involving retinal detachment (P = 0.004) were associated with SRF, while drainage retinotomy was protective (P = 0.03). Persistent SRF was associated with outer retinal band irregularity (30.4 vs. 9.3%, P = 0.005). There were no significant differences in terms of change in best-corrected visual acuity from presentation (P = 0.70), or final best-corrected visual acuity (P = 0.54). CONCLUSION: Eyes with preoperative high myopia and macular involvement, and those in which a drainage retinotomy was not performed, were more likely to develop persistent SRF.
Asunto(s)
Mácula Lútea/patología , Desprendimiento de Retina/cirugía , Líquido Subretiniano/diagnóstico por imagen , Agudeza Visual , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Desprendimiento de Retina/diagnóstico , Estudios Retrospectivos , Tomografía de Coherencia Óptica/métodos , Vitrectomía , Adulto JovenRESUMEN
Inherited retinal diseases (IRDs) cause visual loss due to dysfunction or progressive degeneration of photoreceptors. These diseases show marked phenotypic and genetic heterogeneity. The Israeli IRD consortium (IIRDC) was established in 2013 with the goal of performing clinical and genetic mapping of the majority of Israeli IRD patients. To date, we recruited 2,420 families including 3,413 individuals with IRDs. On the basis of our estimation, these patients represent approximately 40% of Israeli IRD patients. To the best of our knowledge, this is, by far, the largest reported IRD cohort, and one of the first studies addressing the genetic analysis of IRD patients on a nationwide scale. The most common inheritance pattern in our cohort is autosomal recessive (60% of families). The most common retinal phenotype is retinitis pigmentosa (43%), followed by Stargardt disease and cone/cone-rod dystrophy. We identified the cause of disease in 56% of the families. Overall, 605 distinct mutations were identified, of which 12% represent prevalent founder mutations. The most frequently mutated genes were ABCA4, USH2A, FAM161A, CNGA3, and EYS. The results of this study have important implications for molecular diagnosis, genetic screening, and counseling, as well as for the development of new therapeutic strategies for retinal diseases.