Mir-204-5p alleviates mitochondrial dysfunction by targeting IGFBP5 in diabetic cataract.

BACKGROUND: Cataract contributes to visual impairment worldwide, and diabetes mellitus accelerates the formation and progression of cataract. Here we found that the expression level of miR-204-5p was diminished in the lens epithelium with anterior lens capsule of cataract patients compared to normal donors, and decreased more obviously in those of diabetic cataract (DC) patients. However, the contribution and mechanism of miR-204-5p during DC development remain elusive. METHODS AND RESULT: The mitochondrial membrane potential (MMP) was reduced in the lens epithelium with anterior lens capsule of DC patients and the H2O2-induced human lens epithelial cell (HLEC) cataract model, suggesting impaired mitochondrial functional capacity. Consistently, miR-204-5p knockdown by the specific inhibitor also attenuated the MMP in HLECs. Using bioinformatics and a luciferase assay, further by immunofluorescence staining and Western blot, we identified IGFBP5, an insulin-like growth factor binding protein, as a direct target of miR-204-5p in HLECs. IGFBP5 expression was upregulated in the lens epithelium with anterior lens capsule of DC patients and in the HLEC cataract model, and IGFBP5 knockdown could reverse the mitochondrial dysfunction in the HLEC cataract model. CONCLUSIONS: Our results demonstrate that miR-204-5p maintains mitochondrial functional integrity through repressing IGFBP5, and reveal IGFBP5 may be a new therapeutic target and prognostic factor for DC.

Human Primary Lens Epithelial Cultures on Basal Laminas Studied by Synchrotron-Based FTIR Microspectroscopy for Understanding Posterior Capsular Opacification.

Human primary lens epithelial cultures serve as an in vitro model for posterior capsular opacification (PCO) formation. PCO occurs when residual lens epithelial cells (LECs) migrate and proliferate after cataract surgery, differentiating into fibroblastic and lens fiber-like cells. This study aims to show and compare the bio-macromolecular profiles of primary LEC cultures and postoperative lens epithelia LECs on basal laminas (bls), while also analyzing bls and cultured LECs separately. Using synchrotron radiation-based Fourier transform infrared (SR-FTIR) (Bruker, Karlsruhe, Germany) microspectroscopy at the Spanish synchrotron light source ALBA, we observed that the SR-FTIR measurements were predominantly influenced by the strong collagen absorbance of the bls. Cultured LECs on bls showed a higher collagen contribution, indicated by higher vas CH3, CH2 and CH3 wagging and deformation, and the C-N stretching of collagen. In contrast, postoperative LECs on bls showed a higher cell contribution, indicated by the vsym CH2 peak and the ratio between vas CH2 and vas CH3 peaks. The primary difference revealed using SR-FTIR is the greater LEC contribution in spectra recorded from postoperative lens epithelia compared to cultured LECs on bls. IR spectra for bl, cultured LECs and postoperative lens epithelia could be valuable for future research.

[Spontaneous rupture of the anterior lens capsule in Alport syndrome (case study)]. / Samoproizvol'noe vskrytie perednei kapsuly khrustalika pri sindrome Al'porta (klinicheskoe nablyudenie).

Alport syndrome is a hereditary disease characterized by glomerulopathy, manifested by hematuria and/or proteinuria, progressive decline in renal function, often combined with hearing and vision pathology. This article presents a clinical case of spontaneous opening of the anterior lens capsule in a patient with Alport syndrome, accompanied by uveitis and ophthalmic hypertension, and describes the features of the surgical aid and the postoperative period.

[Application of optical coherence tomography in the assessment of the posterior lens capsule during anti-angiogenic therapy]. / Primenenie opticheskoi kogerentnoi tomografii v otsenke zadnei kapsuly khrustalika na fone provedeniya antiangiogennoi terapii.

Intravitreal injection (IVI) of anti-angiogenic drugs is one of the most common therapeutic procedures in ophthalmology. In recent years, a new non-contact study method has been developed - anterior segment optical coherence tomography (AS-OCT), which allows the formation of three-dimensional images of the lens and provides more detailed information about its structure and morphology. PURPOSE: This study uses optical coherence tomography method to analyze the risks of developing changes in the posterior lens capsule in patients after IVI of an anti-angiogenic drug. MATERIAL AND METHODS: The study involved 100 people (14 men and 86 women) with a natural lens and neovascular age-related macular degeneration (nAMD). The average age was 70.57±7.98 years. During the study (12 months), all patients underwent IVI of an anti-angiogenic drug aflibercept in the treat-and-extend (T&E) mode. All subjects were divided into 2 groups: with a total number of IVI less than 10 - group 1 (50 patients), and more than 10 IVI - group 2 (50 patients, of which 49 were included in the study). All patients underwent OCT using the Optopol REVO NX device (Poland) with the Anterior B-scan Wide protocol before inclusion in the study, as well as after 3, 6 and 12 months. RESULTS: It was found that the risk of developing a posterior lens capsule rupture, visualized using OCT, depends on the total number of IVI (correlation coefficient 0.473 p=0.001): the more IVI, the higher the probability that damage to the posterior capsule will occur after the next IVI, and after the 15th injection the risk of developing damage to the posterior capsule increases sharply. CONCLUSION: The astudy analyzed the risk factors for the development of posterior lens capsule damage that can be detected using OCT, and presented three risk groups for the development of rupture (or damage) of the posterior lens capsule depending on the number of intravitreal injections performed.

Prevalence and outcome of lens capsule disruption in routine canine cataract surgery: A retrospective study of 520 eyes (2012-2019).

OBJECTIVE: To investigate the prevalence and surgical outcome of lens capsule disruption (LCD) in dogs undergoing cataract removal. ANIMALS STUDIED: Medical records of 924 eyes undergoing phacoemulsification were analyzed retrospectively. PROCEDURES: Routine cataract surgeries with or without LCD were included. Any LCD other than routine anterior capsulorhexis was defined as LCD and classified according to location and etiology. Odds ratios (OR) were calculated for maintaining vision, implantation of an artificial intraocular lens (IOL), and enucleation. RESULTS: In total, 520 eyes were included. A LCD occurred in 145 eyes (27.8%; 145/520) and affected the posterior (85.5%; 124/145), anterior (6.2%; 9/145), and equatorial lens capsule (4.8%; 7/145) and at multiple locations (3.4%; 5/145). The etiology of the LCD was spontaneous preoperative in 41 eyes (28.3%; 41/145), accidental intraoperative in 57 eyes (39.3%; 57/145), and planned in 47 eyes (32.4%; 47/145). Disruption did not increase the odds of enucleation (OR = 1.48, 95% confidence interval [CI] 0.56-3.67; p = .36). The presence of LCD significantly increased the risk of losing vision 1 year post-operatively (OR = 8.17, 95% CI 1.41-84.93; p = .007) associated with retinal detachment. However, this was not present at 2 years follow-up or in PCCC cases at any time point. An IOL was implanted in 108 eyes (108/145; 75.2%) with LCD and in 45/47 (95.7%) eyes with a PCCC. CONCLUSION: Increased surgeon awareness of possible intraoperative, accidental LCDs is important, as LCDs were relatively common and associated with increased odds for vision loss after 1 year in the present study. A prospective study investigating the causes of intraoperative, accidental LCD is warranted.

[Hybrid (femtolaser) phacoemulsification: technical aspects and functional results]. / Gibridnaya (femtolazernaya) fakoemul'sifikatsiya: tekhnologicheskie aspekty i funktsional'nye rezul'taty.

This article summarizes scientific and practical results of hybrid femtosecond laser-assisted phacoemulsification (HFE) including study of clinical and technical aspects of the intervention and evaluation of post-surgical functional state of the eye on the basis of clinical, morphological and biomechanical data. The HFE technology should be considered the method of choice for microinvasive phaco surgery, its main advantage being the possibility of controlled handling of such important surgical stages as anterior circular continuous capsulorhexis and nucleus fragmentation on a closed eyeball, which significantly reduces the risk of complications and decreases of effective ultrasound time.

Increased Desmosine in the lens capsules is associated with augmented elastin turnover in Pseudoexfoliation syndrome.

Pseudoexfoliation syndrome (PXF) is an idiopathic disease with a high prevalence rate. The elastosis disorder is contributed by genetic and non-genetic factors. Elastin dysregulation associated with the disease mechanism is incompletely understood. This study evaluated the molecules of the elastogenesis machinery in PXF. Lens capsule and aqueous humor (aqH) samples (age/sex-matched) were collected from the eyes with PXF alone and PXF with glaucoma (PXF-G) undergoing Extra Capsular Cataract Extraction (ECCE) surgery. The Elastin turnover was assessed by estimating Desmosine levels in the lens capsules by HPLC analysis. Expression of elastogenesis genes [EMILIN1, CLU, FBN1, FN1, FBLN5, FBLN4 and LOXL1] were evaluated in the lens capsule by qPCR while the proteins were assessed in aqH by western blot analysis. The Desmosine content in the lens capsules were 3-fold and 6-fold elevated in PXF (P = 0.02) and PXF-G (P = 0.01) respectively compared to the cataract-alone, indicating increased elastin degradation. A significant increase in the transcript levels of the CLU, FBLN4, EMILIN1, FBLN5, FN1, FBN1, LOXL1 along with significant changes in protein expression of CLU, FBLN5, FBN1 and LOXL1 signified up-regulation of the elastogenesis machinery. The study provides direct evidence of augmented elastin degradation and turnover in the lens capsule of PXF marked by increased Desmosine content and the expression of proteins involved in mature elastin formation.

Role of fibronectin and IOL surface modification in IOL: Lens capsule interactions.

Posterior Capsule Opacification (PCO) is one of the most common complications of cataract surgery. While studies have shown that IOL material properties and fibronectin adsorption may affect IOL-induced PCO in the clinical setting, the mechanism governing such interactions is not totally understood. Since strong adhesion forces between IOLs and posterior capsules (PCs) have been shown to impede cell infiltration and thus reduce PCO formation, this study was designed to assess whether fibronectin adsorption and IOL material properties would impact the IOL:PC adhesion force and cell infiltration using a PCO predictive in vitro model and a macromolecular dye imaging model, respectively. Our results showed that fibronectin adsorption significantly increased the adhesion forces and reduced simulated cell infiltration between acrylic foldable IOLs and the PC at physiological temperature in comparison to fibronectin-free controls. This fibronectin-mediated strong IOL: PC bond may be contributing to low PCO rates in the clinic for acrylic foldable IOLs. In addition, acrylic foldable IOLs coated with Di(ethylene glycol) (Diglyme), a hydrophilic coating known to reduce protein adsorption, was tested for its ability to alter adhesion force and cell infiltration. We observed that IOLs coated with Diglyme coating greatly reduced surface hydrophobicity and fibronectin adsorption of acrylic foldable IOLs. Furthermore, Diglyme coated IOLs showed significantly reduced adhesion force and increased simulated cell infiltration at the IOL:PC interface. The overall results support the hypothesis that IOL surface properties and their ability to adsorb fibronectin may have great impact on the IOL:PC adhesion force. A tight binding between IOLs and PC may contribute to the reduction of cell infiltration and thus the PCO incidence rate in the clinic.

[On studying the mechanisms and assessing the safety of Nd:YAG laser irradiation of the posterior lens capsule (experimental and clinical study)]. / K voprosu ob izuchenii mekhanizmov i otsenke bezopasnosti Nd:YAG-lazernoi destruktsii zadnei kapsuly khrustalika (eksperimental'no-klinicheskoe issledovanie).

YAG laser interventions are associated with the risk of complications, including corneal. PURPOSE: To study the mechanisms of laser destruction in exposing the posterior lens capsule (PLC) tissue to Nd:YAG laser irradiation, and to evaluate its side effects on the cornea. MATERIAL AND METHODS: The experiment involved 6 autopsy samples of human posterior lens capsule with different optical and mechanical properties, which were exposed to laser irradiation. We used the Nd:YAG ophthalmic laser LPULSA SYL-9000 Premio manufactured by «LightMed¼ (Taiwan/USA) and an experimental Nd:YAG laser system (1.064 µm). The following parameters were compared: the power of the incident radiation and radiation transmitted through the PLC, the mechanical stresses in the PLC tissue, the kinetic energy of the laser ablation products, and the pressure of gas bubbles during laser exposure in capsule samples of different densities. In the clinical part of the work, the negative effects of Nd:YAG laser on the cornea at different PLC densities were assessed using the endothelial microscope SP 3000P («Topcon¼, Japan). RESULTS: The experiment showed that in hard samples of PLC there are star-shaped point perforations with a diameter of 50±20 µm with partial rarefaction around the point defects. Damage to soft PLC samples in the form of large complete perforations was up to 200 µm in size. The temperature of laser irradiation necessary to achieve breakdown in soft PLC samples was 90 °C, in hard samples - 120 °C. The results of the experiment indicate that the final outcome - destruction of the PLC tissue - is safer to achieve not by increasing the energy, but by increasing the number of laser pulses. Clinical study results confirm a significant effect of the density of PLC on the values of laser energy and on the state of the cornea after laser intervention. CONCLUSION: The experimental data on the mechanisms of laser destruction of the lens capsule should contribute to the development of new and improvement of already known technologies aimed at reducing the risks associated with laser surgeries.

[Anatomical, morphological and biomechanical aspects of accommodation]. / Anatomo-morfologicheskie i biomekhanicheskie aspekty akkomodatsii.

The article reviews the findings on the anatomy, morphological and biomechanical features of the accommodation apparatus. Modern methods of imaging and biometry confirm the validity of the Helmholtz lenticular theory of accommodation, according to which its mechanism involves three main components: the ciliary body, the zonular fibres and the lens capsule, the lens itself. Based on this, there is certain interest in studying the degree of participation of each of these components in the development of age-related changes in accommodation (presbyopia).

Lysyl hydroxylase 3 is required for normal lens capsule formation and maintenance of lens epithelium integrity and fate.

Lens abnormalities are a major cause of reduced vision and blindness. One mechanism that can lead to reduced lens transparency, i.e. cataract, is abnormal behavior of lens epithelial cells (LECs), the precursors of the transparent lens fiber cells. Here we describe a zebrafish mutation causing the embryonic lens epithelium to generate cellular masses comprising partially differentiated lens fiber cells. We identify the mutant gene as plod3, which encodes for Lysyl hydroxylase 3 (Lh3), an enzyme essential for modification of collagens, including Collagen IV, a main component of the lens capsule. We show that plod3-deficient lenses have abnormal lens epithelium from an early developmental stage, as well as abnormal lens capsules. Subsequently, upregulation of TGFß signaling takes place, which drives the formation of lens epithelial cellular masses. We identify a similar phenotype in Collagen IVα5-deficient embryos, suggesting a key role for the defective lens capsule in the pathogenesis. We propose that plod3 and col4a5 mutant zebrafish can serve as useful models for better understanding the biology of LECs during embryonic development and in formation of lens epithelium-derived cataract.

Advanced glycation end products in human diabetic lens capsules.

Advanced glycation end products (AGEs) accumulate with age in human lens capsules. AGEs in lens capsules potentiate the transforming growth factor beta-2-mediated mesenchymal transition of lens epithelial cells, which suggests that they play a role in posterior capsule opacification after cataract surgery. We measured AGEs by liquid chromatography-mass spectrometry in capsulorhexis specimens obtained during cataract surgery from nondiabetic and diabetic patients with and without established retinopathy. Our data showed that the levels of most AGEs (12 out of 13 measured) were unaltered in diabetic patients and diabetic patients with retinopathy compared to nondiabetic patients. There was one exception: glucosepane, which was significantly higher in diabetic patients, both with (6.85 pmol/µmol OH-proline) and without retinopathy (8.32 pmol/µmol OH-proline), than in nondiabetic patients (4.01 pmol/µmol OH-proline). Our study provides an explanation for the similar incidence of posterior capsule opacification between nondiabetic and diabetic cataract patients observed in several studies.

Effect of time and temperature-dependent changes of IOL material properties on IOL: Lens capsule interactions.

Posterior Capsule Opacification (PCO) is the most common complication associated with Intraocular Lens (IOL) implantation. Based on the assumption that the interactions between an IOL and the lens capsule (LC) may influence the extent of PCO formation, a new in vitro model was developed to quantify the adhesion force of an IOL to simulated LC using a custom-designed micro-force tester. Using this system, we examined the influence of temperature (room temperature vs. body temperature) and incubation time (0 vs. 24 h) on the adhesion force between IOLs and LCs. The results show that, in line with clinical observations of PCO incidence, the adhesion force increased at body temperature and with increase in incubation time in the following order, Acrylic foldable IOLs > Silicone IOLs > PMMA IOLs. By examining the changes of surface properties as a function of temperature and incubation time, we found that acrylic foldable IOLs showed the largest increase in their hydrophilicity and reported the lowest surface roughness in comparison to other IOL groups. Coincidentally, using a newly established macromolecular dye imaging system to simulate cell migration between IOLs and LC, we observed that the amount of macromolecular dye infiltration between IOLs and LCs was in the following order: PMMA IOLs > Silicone IOLs > Acrylic foldable IOLs. These results support a new potential mechanism that body temperature, incubation time, surface hydrophilicity and smoothness of IOLs greatly contribute to their tight binding to LCs and such tight binding may lead to reduced IOL: LC space, cell infiltration, and thus PCO formation.

An in vitro system to investigate IOL: Lens capsule interaction.

Posterior capsule opacification (PCO) is the most common complication associated with intraocular lens (IOL) implantation. Unfortunately, current in vitro models cannot be used to assess the potential of PCO due to their failure to simulate the posterior curvature of the lens capsule (LC) and IOL, a factor known to affect PCO pathogenesis in clinic. To overcome such a challenge, a new system to study IOL: LC interaction and potentially predict PCO was developed in this effort. It is believed that the interactions between an IOL and the lens capsule may influence the extent of PCO formation. Specifically, strong adhesion force between an IOL and the LC may impede lens epithelial cell migration and proliferation and thus reduce PCO formation. To assess the adhesion force between an IOL and LC, a new in vitro model was established with simulated LC and a custom-designed micro-force tester. A method to fabricate simulated LCs was developed by imprinting IOLs onto molten gelatin to create simulated three dimensional (3D) LCs with curvature resembling the bag-like structure that collapses on the IOL post implantation. By pushing the LC mold vertically downward, while measuring the change in position of the bending bar with respect to its start position, the adhesion force between the IOLs and LCs was measured. An in vitro system that can measure the adhesion force reproducibly between an IOL and LC with a resolution of ~1 µN was established in this study. During system optimization, the 10% high molecular weight gelatin produced the best LC with the highest IOL: LC adhesion force with all test lenses that were fabricated from acrylic foldable, polymethylmethacrylate (PMMA) and silicone materials. Test IOLs exerted different adhesion force with the 3D simulated LCs in the following sequence: acrylic foldable IOL > silicone IOL > PMMA IOL. These results are in good agreement with the clinical observations associated with PCO performance of IOLs made of the same materials. This novel in vitro system can provide valuable insight on the IOL: LC interplay and its relationship to clinical PCO outcomes.

Lens Epithelial Surface Disorders in Exfoliation Syndrome: A Scanning and Transmission Electron Microscopy Study.

BACKGROUND: Hydrodissection was recently reported to occur more easily in patients with exfoliation syndrome (XFS). Transmission electron microscopy (TEM) studies have already revealed alterations of the lens epithelial cells (LECs) and their apical membrane towards the lens fibers. OBJECTIVE: The aim of this work was to examine the three-dimensional appearance of the lens epithelium in patients with XFS. METHODS: Fourteen patients with senile cataract, 7 of whom had XFS, were included. Anterior lens capsules (aLCs) were obtained with continuous curvilinear capsulorrhexis (CCC) during phacoemulsification and were examined with scanning electron microscopy (SEM) and TEM. RESULTS: Exfoliation samples exhibited an overall more irregular apical surface of the lens epithelium compared to control aLCs. The height of LECs varied extensively. On the apical surface of LECs, amorphous, crystalline-like, or microgranular extracellular material and membranous, oval-shaped structures were documented with SEM. All findings were connected to corresponding observations with TEM and were not correlated to the type of cataract. CONCLUSIONS: In XFS patients, the lens epithelial surface exhibited a highly irregular margin, with extracellular material covering the apical membrane of LECs. We suggest that XFS probably causes both epithelial and lens fiber degeneration which, during CCC and mechanical extraction of the aLC from the lens cortex, result in diverse alterations.

UV Effect on Human Anterior Lens Capsule Macro-Molecular Composition Studied by Synchrotron-Based FTIR Micro-Spectroscopy.

Ultraviolet (UV) irradiation is an important risk factor in cataractogenesis. Lens epithelial cells (LECs), which are a highly metabolically active part of the lens, play an important role in UV-induced cataractogenesis. The purpose of this study was to characterize cell compounds such as nucleic acids, proteins, and lipids in human UV C-irradiated anterior lens capsules (LCs) with LECs, as well as to compare them with the control, non-irradiated LCs of patients without cataract, by using synchrotron radiation-based Fourier transform infrared (SR-FTIR) micro-spectroscopy. In order to understand the effect of the UV C on the LC bio-macromolecules in a context of cataractogenesis, we used the SR-FTIR micro-spectroscopy setup installed on the beamline MIRAS at the Spanish synchrotron light source ALBA, where measurements were set to achieve a single-cell resolution with high spectral stability and high photon flux. UV C irradiation of LCs resulted in a significant effect on protein conformation with protein formation of intramolecular parallel ß-sheet structure, lower phosphate and carboxyl bands in fatty acids and amino acids, and oxidative stress markers with significant increase of lipid peroxidation and diminishment of the asymmetric CH3 band.

Clinical course of lens capsule fragment adherent to the posterior corneal surface after cataract surgery.

PURPOSE: The purpose of the study was to evaluate the clinical features and outcomes of lens capsule fragment (LCF) adherent to the posterior corneal surface after cataract surgery. Methods A total of 12 eyes from 12 patients were included with a mean follow-up duration of 19.4 ± 12.6 months. Demographics and clinical features were collected by reviewing medical records and slitlamp photographs. Outcome parameters included corrected distance visual acuity (CDVA), central corneal thickness, and anterior segment optical coherence tomography (AS-OCT) features. Results All LCF located centrally and remained fixed and turned to semitransparent in a mean time of 28.7 ± 20.1 days. The AS-OCT revealed an extra membrane at the posterior corneal surface, with an underlying intact Descemet membrane in 9 eyes. All patients experienced corneal edema associated with LCF, which was medically managed and resolved in a mean time of 58.1 ± 40.2 days. CDVA improved from logarithm of minimum angle of resolution scores of 0.91 ± 0.63 preoperatively to 0.25 ± 0.18 at 2 months after surgery. None of the patients expressed subjective visual complaints. Conclusions LCF adherent to the posterior corneal surface caused prolonged corneal edema after cataract surgery, but exhibited no clinically significant complications in the midterm follow-up. AS-OCT provided useful diagnostics and differentiating features.

[Assessment of age-related changes in lens capsule biomechanics using atomic force microscopy]. / Otsenka vozrastnykh izmenenii «biomekhaniki¼ kapsuly khrustalika na osnove atomno-silovoi mikroskopii.

Studies devoted to the assessment of lens capsule biomechanics can be divided into fundamental and applied. The former are oriented towards analysis of various indicators characterizing elasticity of the capsule as a basal membrane that maintains and changes the shape of the lens, and the latter deal with widespread introduction of modern microinvasive methods of phaco surgery into clinical practice. PURPOSE: To assess age-related changes in lens capsule biomechanics based on atomic force microscopy (AFM). MATERIAL AND METHODS: The study included 50 central fragments of the anterior capsule of the human lens obtained intraoperatively during ultrasonic phacoemulsification by continuous circular capsulorhexis. The measurements were carried out in the Fast Force Volume (FFV) mode. The force curves were processed in the Nanoscope Analysis software (Bruker, USA) using the Hertz model that allows calculating the Young's modulus of the capsule sample based on the dependence of the force on the puncture depth. RESULTS: There was no statistically significant difference in the «stiffness¼ of the inner and outer surfaces before and after removal of the subcapsular epithelium (p=0.25). In all cases, the inner surface of the capsule turned out to be «harder¼ than the outer one. In this case, the ratio of Young's modulus of the inner and outer surfaces has a significant dependence on age (p<0.001). With an increase in age from 50 to 90 years, this ratio decreased from ~7 to ~1.5. This was due to a simultaneous change in Young's modulus of the opposite nature: an increase in the stiffness of the outer surface and its decrease in the inner one. CONCLUSION: It is possible to assess lens capsule biomechanics using AFM if the subcapsular epithelium is present. In this case, the objects of study are the areas of the capsule free of epithelium, and the epithelial cells themselves can be used to identify the inner surface of the capsule. Regardless of age, the stiffness of the inner surface of the anterior lens capsule significantly exceeds that of the outer surface.

Requirement for Crk and CrkL during postnatal lens development.

The Crk and CrkL adaptor proteins have SH2 and SH3 domains and play essential overlapping, as well as distinct, roles in many biological processes, ranging from cell structure and motility to proliferation. Conditional ablation of both Crk and CrkL in neuronal progenitor cells, using a Nestin-Cre transgene, resulted in severe defects in postnatal eye development, including progressive eye closure, lens rupture, and retinal malformation. These phenotypes were not observed in the presence of a single wild-type allele of either Crk or CrkL. We found that the lens in knockout mice started to rupture and disintegrate between postnatal days 7 and 12, although the structure of the retina was relatively well maintained. As the lens deteriorated further, the outer nuclear layer in the posterior of the retina enlarged and developed ruffles. Cre recombination occurred in the lens and retina of the knockout mice. Furthermore, the posterior lens capsule of the knockout mouse was thinner at postnatal days 0.5 and 3, suggesting that the defective lens capsule caused rupturing of the lens near the posterior pole. These results indicate that Crk and CrkL play essential overlapping roles in postnatal lens development.

A case of dense pigment deposition of the posterior lens capsule.

BACKGROUND: Pigment dispersion syndrome (PDS) is a well-known entity which can lead to pigmentary glaucoma (PG). This case report presents a rare presentation of PG with bilateral dense pigment deposits of the posterior lens capsule. CASE PRESENTATION: A 72-year-old male came for his first appointment due to an asymmetric worsening of visual acuity. The examination showed unilaterally severely increased intraocular pressure, bilateral dense pigment deposition of the posterior lens capsule, and a shallow unilateral optic disk excavation. Gonioscopy revealed moderate pigmentation of the angle and a concave configuration of the peripheral iris in both eyes. The standard slit lamp examination showed no transillumination defects of either iris. Optical coherence tomography showed retinal nerve fiber layer (RNFL) thinning in the peripapillary and macular regions. An antiglaucoma medication was prescribed with a good lowering effect. CONCLUSION: Pigment deposition of the posterior lens capsule, which has been rarely reported, is a possible important sign of PDS or PG.