Thermoresponsive GenisteinNLC-dexamethasone-moxifloxacin multi drug delivery system in lens capsule bag to prevent complications after cataract surgery.

Cataract surgery is the most common intraocular procedure. To decrease postsurgical inflammation, prevent infection and reduce the incidence of secondary cataract, we built a temperature-sensitive drug delivery system carrying dexamethasone, moxifloxacin and genistein nanostructured lipid carrier (GenNLC) modified by mPEG-PLA based on F127/F68 as hydrogel. Characterizations and release profiles of the drug delivery system were studied. In vitro functions were detected by CCK-8 test, immunofluorescence, wound-healing assay, real time-PCR and western blotting. The size of GenNLCs was 39.47 ± 0.69 nm in average with surface charges of - 4.32 ± 0.84 mV. The hydrogel gelation temperature and time were 32 °C, 20 s with a viscosity, hardness, adhesiveness and stringiness of 6.135 Pa.s, 54.0 g, 22.0 g, and 3.24 mm, respectively. Transmittance of the gel-release medium was above 90% (93.44 ± 0.33% to 100%) at range of 430 nm to 800 nm. Moxifloxacin released completely within 10 days. Fifty percent of dexamethasone released at a constant rate in the first week, and then released sustainably with a tapering down rate until day 30. Genistein released slowly but persistently with a cumulative release of 63% at day 40. The thermoresponsive hydrogel inhibited the proliferation, migration and epithelial-mesenchymal transition of SRA 01/04 cells, which were confirmed by testing CCK-8, wound-healing assay, western blot, real time-PCR (RT-PCR) and immunofluorescence. These results support this intracameral thermoresponsive in situ multi-drug delivery system with programmed release amounts and release profiles to cut down the need of eye drops for preventing inflammation or infection and to reduce posterior capsular opacification following cataract surgery.

Resveratrol Inhibits Wound Healing and Lens Fibrosis: A Putative Candidate for Posterior Capsule Opacification Prevention.

Purpose: Posterior capsule opacification (PCO) is a common complication of cataract surgery. In addition to improved surgical methods and IOL designs, it is likely additional agents will be needed to improve patient outcomes. Presently no pharmacological agent is in clinical use to prevent PCO. Here we investigate the putative ability of resveratrol (RESV), a naturally occurring polyphenol, as a therapeutic agent. Methods: The human lens epithelial cell line FHL124, a human lens capsular bag model, and central anterior epithelium were used as experimental systems. Standard culture was in 5% fetal calf serum Eagle's minimum essential medium; 10 ng/mL transforming growth factor-ß2 (TGFß2) was used to induce fibrotic changes. A scratch wound assay was used to measure cell migration and the patch assay was used to assess matrix contraction by FHL124 cells. Protein expression was assessed by immunocytochemistry and Western blot and gene expression by quantitative RT-PCR. In capsular bags, cell growth across the posterior lens capsule, capsular wrinkling, and epithelial-to-mesenchymal transition were determined by image analysis. Results: In FHL124 cells, addition of 30 µM RESV significantly impeded cell migration in a wound-healing assay. RESV significantly inhibited TGFß2-induced expression of the myofibroblast marker alpha-smooth muscle actin (α-SMA) at both the message and protein levels, as well as significantly inhibiting matrix contraction induced by TGFß2. In human capsular bags, 30 µM RESV significantly inhibited cell growth. TGFß2-induced α-SMA expression and capsular wrinkling were also significantly inhibited by RESV treatment. RESV significantly suppressed expression of TGFß2-induced genes associated with fibrotic disease, including matrix metalloproteinase-2 in FHL124 cells, capsular bags, and central anterior epithelium. Conclusions: RESV can counter PCO-related physiological events in two human lens model systems. RESV therefore has the potential to be used as a candidate agent for the prevention of PCO, which in turn could benefit millions of cataract patients.

Topical administration of a ROCK inhibitor prevents anterior subcapsular cataract induced by UV-B irradiation.

The deposition of extracellular matrix (ECM)-which is mainly composed of type I collagen-in anterior subcapsular cataracts (ASCs) during epithelial-to-mesenchymal transition (EMT) of lens epithelial cells (LECs) decreases visual function. Transforming growth factor (TGF)-ß is a key factor in the induction of EMT in LECs. Although Rho kinase (ROCK) plays an important role in EMT induced by TGF-ß, it is unknown whether ROCK inhibition affects type I collagen expression in TGF-ß-stimulated LECs and ASC formation. This was investigated in the present study both in vitro using human lens epithelium (HLE)-B3 cells and in vivo using mice with ultraviolet radiation (UVR)-B-induced cataracts. We found that TGF-ß2 increased type I collagen mRNA expression in HLE-B3 cells; this was inhibited in a dose-dependent manner by treatment with the ROCK inhibitor Y-27632. UVR-B exposure caused ASC formation in mice. A histopathological examination revealed that LECs in the anterior subcapsular area were flattened and multi-layered, and had a spindle shape in cross section. Immunohistochemical analysis revealed the presence of α-smooth muscle actin and type I collagen around these flattened LECs; these opacities were reduced by topical instillation of Y-27632. These findings suggest that suppression of TGF-ß signaling in LECs by topical application of a ROCK inhibitor can prevent the formation of ASCs.

Comparison of trypan blue and Brilliant Blue G for staining of the anterior lens capsule during cataract surgery: short-term results.

PURPOSE: The present study aimed to evaluate the potential corneal endothelial cell toxicity of trypan blue (TB) and Brilliant Blue G (BBG), two dyes used to stain the anterior capsule in cataract surgery. METHODS: We conducted a single-center, prospective, randomized study in which 150 eyes of 117 patients were randomly divided into control (CT), TB, and BBG groups. Preoperative and postoperative (1, 3, and 6 months) values for corrected distance visual acuity (CDVA), corneal endothelial cell count, and central corneal thickness were compared among the three groups. RESULTS: A total of 111 eyes from 88 patients were completely analyzed. The CDVA (logarithm of the minimal angle of resolution) values in the CT, TB, and BBG groups 1 month after surgery were 0.001, 0.023, and 0.019, respectively. The corneal endothelial cell counts 6 months after surgery were 2711 ± 225, 2748 ± 251, and 2680 ± 284 cells/mm2, respectively. The central corneal thicknesses 6 months after surgery were 524.3 ± 35.5, 532.2 ± 36.1, and 531.4 ± 33.0 µm, respectively. There were no significant differences in CDVA, endothelial cell count, or central corneal thickness among the three groups during the follow-up period. CONCLUSIONS: Our findings indicate that neither TB nor BBG was associated with detectable toxicity to corneal endothelial cells during cataract surgery, even when injected directly into the anterior chamber. Additionally, BBG exhibited equivalent staining efficiency to TB.

Prevention of posterior capsule opacification through intracapsular hydrogen peroxide or distilled water treatment in human donor tissue.

In order to determine whether posterior capsule opacification after cataract surgery, could be delayed or inhibited through the application of hydrogen peroxide (H2O2) or distilled water (H2Od),we extracted lens capsules from 25 human donor eye globes. Samples were treated for 5 min with either 30 mM H2O2 or H2Od or used as controls, and cultured for one month, during which dark field and tilt illumination photos were taken. These were used to observe and quantify, time until cellular growth and confluence on the posterior capsule. After culture, histological sections were stained for H&E, α-SMA, Ki-67 and vimentin and evaluated. We prevented cellular growth in 50% of H2Od and 58% H2O2 of treated samples. The overall prevention of cell growth compared to cultured controls was significant for both treatments while there was no significant difference between them. In the cases where cellular growth was not prevented, both treatments significantly delay cellular growth. Until day 28 none of the treated samples of either type that had shown growth reached total confluence. All cultured controls reached total confluence before treated samples (median = day 11.5). Also, histologically, there was a clear morphological difference between cultured controls and treated samples.

Poly(lactic-co-glycolic) Acid as a Slow-Release Drug-Carrying Matrix for Methotrexate Coated onto Intraocular Lenses to Conquer Posterior Capsule Opacification.

PURPOSE: Posterior capsule opacification (PCO) still represents the main long-term complication of cataract surgery. Research into pharmacologic PCO prophylaxis is extensive. One promising candidate drug is methotrexate (MTX). Our aim is to determine the in vitro feasibility of MTX-loaded poly(lactic-co-glycolic) (PLGA) biomatrices sprayed on intraocular lenses (IOLs) as a drug-delivery implant. METHODS: Hydrophilic and hydrophobic acrylic IOLs were spray-coated with MTX-loaded PLGA. Unsprayed, solvent only, and solvent-PLGA-sprayed IOLs served as controls. All IOLs were evaluated for their growth-inhibiting properties in an in vitro anterior segment model and the ex vivo human capsular bag. The release kinetics of MTX from the IOLs was determined. The toxicity of MTX on corneal endothelial cells was evaluated by using a dye reduction colorimetric assay. MTX was also used in a scratch assay. RESULTS: MTX-PLGA-IOL showed a significant difference in cell proliferation and migration compared with all controls in the anterior segment model (p < 0.001) and in the human capsular bag model (p = 0.04). No difference in viability was observed on corneal endothelial cells (p = 0.43; p = 0.61). MTX significantly inhibited cells in the scratch assay (p = 0.02). At all measured points, the released MTX dose remained above EC50 and below the toxic dose for the endothelium. CONCLUSIONS: In view of the strong inhibition of PCO in vitro with the lack of toxic effects on a corneal cell line, MTX encapsulating microspheres seem to be a promising method for modifying IOL.

p-Benzoquinone-induced aggregation and perturbation of structure and chaperone function of α-crystallin is a causative factor of cigarette smoke-related cataractogenesis.

Cigarette smoking is a significant risk factor for cataract. However, the mechanism by which cigarette smoke (CS) causes cataract remains poorly understood. We had earlier shown that in CS-exposed guinea pig, p-benzoquinone (p-BQ) derived from CS in the lungs is carried by the circulatory system to distant organs and induces various smoke-related pathogeneses. Here, we observed that CS exposure caused accumulation of the p-BQ-protein adduct in the eye lens of guinea pigs. We also observed accumulation of the p-BQ-protein adduct in resected lens from human smokers with cataract. No such accumulation was observed in the lens of never smokers. p-BQ is a strong arylating agent that forms Michael adducts with serum albumin and haemoglobin resulting in alterations of structure and function. A major protein in the mammalian eye lens is αA-crystallin, which is a potent molecular chaperone. αA-crystallin plays a key role in maintaining the integrity and transparency of the lens. SDS-PAGE indicated that p-BQ induced aggregation of αA-crystallin. Various biophysical techniques including UV-vis spectroscopy, fluorescence spectroscopy, FT-IR, bis-ANS titration suggested a perturbation of structure and chaperone function of αA-crystallin upon p-BQ modification. Our results indicate that p-BQ is a causative agent involved in the modification of αA-crystallin and pathogenesis of CS-induced cataract. Our findings would educate public about the impacts of smoking on eye health and help to discourage them from smoking. The study might also help scientists to develop new drugs for the intervention of CS-induced cataract at an early stage.

Evaluación de la concetracion optima del azul de tripan para la tincion de la capsula anterior del cristalino en la cirugia de catarata / Evaluation of the optimal concentration of trypan blue for the anterior lens capsule staining in cataract surgery

ANTECEDENTES: Las tinciones capsulares constituyen uno de los mayores avances en la cirugía oftálmica al permitir la tinción de la cápsula anterior del cristalino en las cirugías de catarata. El azul de tripán se utiliza en los casos en los que no se visualiza de forma adecuada la cápsula anterior del cristalino cuando el reflejo rojo es pobre o nulo. Diferentes estudios señalan que el azul de tripán es un colorante eficaz y seguro para la tinción de la cápsula anterior del cristalino. METODOLOGIA: En la presente revisión se evaluó las diferencias en la efectividad entre las distintas concentraciones del azul del tripán. RESULTADOS: Los resultados muestran que el azul de tripán es una coloración segura y útil para la tinción de la cápsula anterior del cristalino. CONCLUSION: El azul de tripán tiene una amplia ventana terapéutica que permite ser utilizado a distintas concentraciones (0.0125%, 0.06%, 0.1%, 0.4% y 0.6%). Sin embargo, un estudio indicó que la concentración efectiva más baja para teñir el cristalino fue la de 0.1%.

Bottom-up fabrication of zwitterionic polymer brushes on intraocular lens for improved biocompatibility.

Intraocular lens (IOL) is an efficient implantable device commonly used for treating cataracts. However, bioadhesion of bacteria or residual lens epithelial cells on the IOL surface after surgery causes postoperative complications, such as endophthalmitis or posterior capsular opacification, and leads to loss of sight again. In the present study, zwitterionic polymer brushes were fabricated on the IOL surface via bottom-up grafting procedure. The attenuated total reflection-Fourier transform infrared and contact angle measurements indicated successful surface modification, as well as excellent hydrophilicity. The coating of hydrophilic zwitterionic polymer effectively decreased the bioadhesion of lens epithelial cells or bacteria. In vivo intraocular implantation results showed good in vivo biocompatibility of zwitterionic IOL and its effectiveness against postoperative complications.

FGF2 antagonizes aberrant TGFß regulation of tropomyosin: role for posterior capsule opacity.

Transforming growth factor (TGF) ß2 and fibroblast growth factor (FGF) 2 are involved in regulation of posterior capsule opacification (PCO) and other processes of epithelial-mesenchymal transition (EMT) such as cancer progression, wound healing and tissue fibrosis as well as normal embryonic development. We previously used an in vivo rodent PCO model to show the expression of tropomyosin (Tpm) 1/2 was aberrantly up-regulated in remodelling the actin cytoskeleton during EMT. In this in vitro study, we show the Tpms family of cytoskeleton proteins are involved in regulating and stabilizing actin microfilaments (F-actin) and are induced by TGFß2 during EMT in lens epithelial cells (LECs). Importantly, we found TGFß2 and FGF2 played contrasting roles. Stress fibre formation and up-regulation of α-smooth muscle actin (αSMA) induced by TGFß2 could be reversed by Tpm1/2 knock-down by siRNA. Expression of Tpm1/2 and stress fibre formation induced by TGFß2 could be reversed by FGF2. Furthermore, FGF2 delivery to TGFß-treated LECs perturbed EMT by reactivating the mitogen-activated protein kinase (MAPK)/ extracellular signal-regulated kinase (ERK) pathway and subsequently enhanced EMT. Conversely, MEK inhibitor (PD98059) abated the FGF2-mediated Tpm1/2 and αSMA suppression. However, we found that normal LECs which underwent EMT showed enhanced migration in response to combined TGFß and FGF2 stimulation. These findings may help clarify the mechanism reprogramming the actin cytoskeleton during morphogenetic EMT cell proliferation and fibre regeneration in PCO. We propose that understanding the physiological link between levels of FGF2, Tpm1/2 expression and TGFßs-driven EMT orchestration may provide clue(s) to develop therapeutic strategies to treat PCO based on Tpm1/2.

Effects of peptide ratios in nanofibre-based hydrogels for the prevention of capsular opacification.

PURPOSE: To moderate the capsular opacification (CO) response after lens surgery, an experimental study was performed in which nanofibre-based hydrogels (nanogels) with different ratios of attached peptides were applied to provide extracellular matrix-related cues for lens epithelial cells (LECs) in a porcine eye model. METHODS: The lens content was removed, and the capsules were refilled with nanogel. Lenses were divided into two groups, the first group (n = 34) was refilled with nanogels containing different ratios of two laminin-derived peptides (IKVAV + YIGSR), and the latter group (n = 26) was refilled with nanogel combinations of a fibronectin-derived and a type IV collagen-derived peptide (RGDS + DGEA). Two lenses were refilled with culture medium to investigate the effect of the medium on LECs. After refilling, lenses were extracted and cultured for 3 weeks. Lens epithelial cells (LECs) were assessed for morphology and alpha-smooth muscle actin (αSMA) expression using confocal laser scanning microscopy. RESULTS: Differences were seen in cell morphology between lenses refilled with nanogels with IKVAV + YIGSR and RGDS + DGEA peptides. In nanogels with IKVAV + YIGSR peptides, differences in LEC morphology were largest when ratios between the peptides were unequal, whereas LEC responses from the RGDS + DGEA refilled groups showed variation in LEC morphology dependent on the total quantity of mixed-in peptides. The culture medium did not induce proliferation or transformation of LECs. CONCLUSIONS: Ratios and concentrations of cell adhesion-mediating peptides both can direct the LEC response, depending on the adhesion molecules of origin, by influencing LEC proliferation and transformation. Nanogels with incorporated peptides may be tuned towards CO prevention.

CtBP2 Regulates TGFß2-Induced Epithelial-Mesenchymal Transition Through Notch Signaling Pathway in Lens Epithelial Cells.

BACKGROUND: Epithelial-mesenchymal transition (EMT) of human lens epithelial cells (LECs) contributes to posterior capsule opacification (PCO). C-terminal binding protein 2 (CtBP2) has been reported to be essential in EMT and embryonic development. However, the function of CtBP2 in EMT of LECs is unknown. The goal of this study was to investigate the role of CtBP2 through Notch signaling in transforming growth factor ß2 (TGFß2)-induced EMT in LECs. METHODS: The human LEC line SRA01/04 was cultured in the presence of TGFß2 for different periods of time or with γ-Secretase Inhibitor IX (DAPT), a specific inhibitor of Notch receptor cleavage, for 24 h, utilizing plasmid-based method. The levels of protein expression of CtBP2, EMT markers, and Notch signaling molecules were measured by Western bolts. RESULTS: Treatment of SRA01/04 cells with TGFß2 induced typical molecular changes of EMT and increased the expression of CtBP2 in a time-dependent manner. Similarly, the expressions of Jagged1 and Notch1 were increased after TGFß2 treatment. Knockdown of CtBP2 by specific siRNA inhibited TGFß2-induced changes of Connexin 43 (CX43), α-smooth muscle actin (α-SMA), Notch1, and Notch intracellular domain (NICD). In addition, treatment of LECs with ectopic expression of CtBP2 changed the expressions of CX43, α-SMA, Notch1, and NICD, but blockade of Notch pathway with DAPT inhibited CtBP2-induced changes of α-SMA and CX43. CONCLUSION: Our data suggest that CtBP2 plays a critical role in TGFß2-induced EMT via the Jagged/Notch signaling pathway in human LECs and may contribute to the development of PCO.

SIRT1 Protects Human Lens Epithelial Cells Against Oxidative Stress by Inhibiting p53-Dependent Apoptosis.

PURPOSE: This study aims to test the hypothesis that sirtuin type 1 (SIRT1) plays a role in modulating resistance against oxidative stress in lens epithelial cells (LECs), and to determine its mechanism if this hypothesis is found to be true. METHODS: Cultured LECs were treated with resveratrol (RES, an activator of SIRT1) or nicotinamide (NAM, a SIRT1 inhibitor) and incubated with H2O2. Changes in SIRT1, p53, and acetyl-p53 expressions were measured. Cell proliferation was assessed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide assay. TUNEL assay was used to evaluate apoptosis. Pifithrin-α (PFT-α) was applied to block the p53 pathway. RESULTS: SIRT1 expressions significantly increased with H2O2 treatment and further increased with RES treatment in a dose-dependent manner. RES eliminated cellular morphological changes related to H2O2 treatment, increased cell proliferation, and inhibited apoptosis under oxidative stress. In contrast, NAM enhanced cell apoptosis under oxidative stress and decreased cell proliferation. RES caused a dose-dependent decrease in acetyl-p53 levels under oxidative stress, while NAM increased p53 acetylation. Under oxidative conditions, PFT-α, a p53 pathway inhibitor, eliminated the destructive effect of NAM. PFT-α decreased the morphological changes in LECs compared to NAM treatment and increased cell proliferation and inhibited apoptosis. CONCLUSIONS: SIRT1 protected LECs from oxidative stress via the inhibition of the p53 pathway. SIRT1 or SIRT1 activators could potentially be used to prevent ocular aging and cataract in the future.

Injectable intraocular telescope: Pilot study.

PURPOSE: To assess the feasibility of a new injectable telescopic intraocular lens (IOL). SETTING: London Eye Hospital, London, United Kingdom. DESIGN: Prospective interventional pilot study. METHOD: Eyes with bilateral, intermediate, or advanced dry age-related macular degeneration (AMD); preoperative decimal corrected distance visual acuity (CDVA) of 0.25 or less; and improvement with extraocular simulation of the intervention had implantation of 2 IOLs designed for use together in a Galilean telescope configuration (iolAMD). Patients were followed for 4 months. Safety was assessed by monitoring visual acuity, intraocular pressure, specular microscopy, and anterior segment and macular optical coherence tomographies. Fixation stability and macular sensitivity were determined using microperimetry in some eyes. RESULTS: There were no significant intraoperative or postoperative complications. In 1 eye, an anterior sulcus IOL was replaced; there were no sequelae. The mean endothelial cell density was reduced by 18%. The mean decimal CDVA improved from 0.12 preoperatively to 0.20 at 4 months, a 67% gain. The mean change in spherical equivalent after implantation was -1.5 diopters (D) with 0.5 D of induced astigmatism. Microperimetric testing indicated a magnification effect and a deviation of the retinal image by up to 5 degrees, with improved fixation stability. CONCLUSIONS: This injectable intraocular miniature telescope appears safe in the short to medium term and capable of improving visual function. No significant issues were encountered regarding candidate eye selection or patient retention and cooperation. Further work is needed to evaluate the safety and efficacy of the device, particularly with respect to daily-living activities and the range of indications. FINANCIAL DISCLOSURE: Dr. Qureshi has a financial interest in London Eye Hospital Pharma. No other author has a financial or proprietary interest in any material or method mentioned.

Glued capsular hook: technique for fibrin glue-assisted sutureless transscleral fixation of the capsular bag in subluxated cataracts and intraocular lenses.

We describe a technique that uses a capsular hook to obtain sutureless fibrin glue-assisted transscleral fixation of the capsular bag. The hook passes through a sclerotomy created under a scleral flap and engages the capsulorhexis rim, providing scleral fixation intraoperatively and postoperatively. A standard capsular tension ring expands the capsular fornix. The haptic of the hook is tucked into a scleral tunnel for postoperative fixation. The scleral flap is closed with fibrin glue. The glued capsular hook is used for subluxated cataracts and IOLs. It anchors the capsular bag to the sclera, providing vertical and horizontal stability, and stabilizes the bag intraoperatively and postoperatively. The technique was used in 7 patients, who were followed for more than 4 months.

Prevention of capsule opacification after accommodating lens refilling: pilot study of strategies evaluated in a monkey model.

PURPOSE: To test 2 strategies to prevent capsule opacification after accommodating lens refilling in a rhesus monkey model. SETTING: Animal laboratory and laboratory of European university medical centers. DESIGN: Experimental study. METHODS: Six rhesus monkeys had refilling of the lens capsular bag. In the first strategy, before it was filled with a silicone polymer, the capsular bag was treated with noncommercial sodium hyaluronate 1.0% containing cytotoxic substances. In the second strategy, the capsular bag was filled with clinically used sodium hyaluronate 1.0% (Healon) after treatment with actinomycin-D. Slitlamp inspection was performed during a follow-up of 40 to 50 weeks. After enucleation, magnetic resonance images were obtained and confocal fluorescence imaging was performed. RESULTS: Using the first strategy, capsule opacification developed in all eyes. Using the second strategy, 1 monkey did not develop capsule opacification after a 9-month follow-up. In a second monkey, the lens capsule remained clear for 3 months, after which the hyaluronate refill material was exchanged with a silicone polymer and capsule opacification developed. Combining these results with those in a previous study, the difference in opacification between silicone and sodium hyaluronate as refilling materials was statistically significant (P<.01). CONCLUSIONS: That no capsular bag fibrosis occurred in the presence of hyaluronate suggests that the properties of hyaluronate are the reason that remaining lens epithelial cells do not develop into fibrotic cells. The choice of a suitable lens-refilling material prevents the development of capsule opacification. FINANCIAL DISCLOSURE: Mr. Terwee was an employee of Abbott Medical Optics B.V. during the study period. No other author has a financial or proprietary interest in any material or method mentioned.

Histone deacetylase inhibitors trichostatin A and vorinostat inhibit TGFß2-induced lens epithelial-to-mesenchymal cell transition.

PURPOSE: Posterior capsule opacification (PCO) after cataract surgery is due in part to proliferation of the adhering lens epithelial cells and transdifferentiation into mesenchymal cells. The histone deacetylase (HDAC) inhibitors, trichostatin A (TSA) and vorinostat (suberoylanilidehydroxamic acid [SAHA]) are known to modulate cell proliferation and epithelial-mesenchymal transition (EMT). Studies have shown that TGFß2 can induce EMT similar to that seen during PCO. This study evaluated the effects of TSA and SAHA on TGFß2-induced EMT in lens epithelial explants. METHODS: Epithelial cells adherent to lens capsules were isolated from fresh pig lenses and human donor lenses and cultured for 12 hours. Explants were pretreated with TSA or SAHA for 1 hour and then treated with TGFß2 for up to 3 days. Scratch wound healing assay was used to determine epithelial cell proliferation and migration in the samples. The effects of TSA and SAHA on histone acetylation and HDAC 1 to 6 levels were analyzed by Western blotting. RESULTS: Western blotting and immunocytochemistry demonstrated high expression of α-SMA in lens epithelial cells treated with TGFß2. The HDAC inhibitors exerted dose-dependent inhibition of α-SMA expression, with complete inhibition occurring with 0.5 µM of TSA and 2.5 µM of SAHA. Transforming growth factor ß2-induced EMT was suppressed by TSA and SAHA. Histone deacetylase inhibition in pig lens epithelia led to increased acetylation of histone 3 and 4 at multiple sites. CONCLUSIONS: Histone deacetylase inhibitors, TSA, and SAHA prevent EMT in lens epithelial explants. The results also suggest that the epigenetic modifiers are the potential targets to control PCO after cataract surgery.

Accommodation amplitudes after an accommodating intraocular lens refilling procedure: in vivo update.

PURPOSE: To evaluate whether a new capsular bag-refilling procedure provides some accommodation in monkey eyes and to assess the difference in accommodation with different volumes of capsular bag refilling. SETTING: Jinshikai Medical Foundation, Nishi Eye Hospital, Osaka, Japan. DESIGN: Experimental study. METHODS: A central 3.0 to 4.0 mm continuous curvilinear capsulorhexis was created, after which phacoemulsification was performed in the usual manner. A new accommodating-membrane intraocular lens (IOL) for sealing the capsular opening was implanted in the capsular bag. Silicone polymers were injected beneath the IOL into the capsular bag through the delivery hole. In 3 study groups, each with 6 monkey eyes, the lens capsule was refilled with 0.080 mL of silicone polymers, corresponding to a 65% bag volume; 0.100 mL, corresponding to an 80% bag volume; or 0.125 mL, corresponding to a 100% bag volume. To calculate the accommodation amplitudes achieved, automated refractometry was performed before and 1 hour after topical pilocarpine 4.0% application preoperatively and 4 weeks postoperatively. RESULTS: The refilling technique was successful without polymer leakage in all monkeys. Four weeks after surgery, the mean accommodation amplitudes were 2.56 diopters (D) ± 0.74 (SD), 2.42 ± 1.00 D, and 2.71 ± 0.63 D, respectively, in the 3 study groups. CONCLUSIONS: The technique provided some accommodation in young monkey eyes. Leakage of the injectable silicone polymers and anterior capsule opacification in the visual axis were avoided. The results suggest that the capsular bag-refilling procedure warrants further study for possible clinical application. FINANCIAL DISCLOSURE: All authors have a proprietary interest in the accommodating membrane IOL mentioned in the article.