Novel cataract-causing variant c.177dupC in c-MAF regulates the expression of crystallin genes for cell apoptosis via a mitochondria-dependent pathway.

Congenital cataract (CC) is regarded as the most common hereditary ophthalmic disease in children. Mutations in CC-associated genes play important roles in CC formation, which provides the basis for molecular diagnosis and therapy. Among these CC-associated genes, v-maf avian musculoaponeurotic fibrosarcoma oncogene homolog (c-MAF) is considered an important transcription factor for eye and lens development. In this study, we recruited a three-generation Chinese Han family with CC. Gene sequencing revealed a novel duplication mutation in c-MAF (NM_005360.5: c.177dup) that caused frameshifting at residue 60 (p. M60fs) of c-MAF. Additionally, in the patient blood samples, the expression levels of related crystallin and noncrystallin genes confirmed that this novel duplication variant impaired the transactivation of c-MAF. Further functional analyses suggested that the c-MAF mutant induces the transcriptional inhibition of CRYAA and CRYGA and subsequently influences ME and G6PD expression levels, ultimately resulting in ROS generation and further leading to cell apoptosis via mitochondria-dependent pathways. In conclusion, we report a novel c-MAF heterozygous mutation that plays a vital role in CC formation in a Chinese family, broadening the genetic spectrum of CC.

GJA8 missense mutation disrupts hemichannels and induces cell apoptosis in human lens epithelial cells.

Autosomal dominant congenital cataract (ADCC), the most common hereditary disease, is a major cause of eye disease in children. Due to its high genetic and clinical heterogeneity, the identification of ADCC-associated gene mutations is essential for the development of molecular therapies. In this study, we examined a four-generation Chinese pedigree with ADCC and identified putative mutations in ADCC candidate genes via next-generation sequencing (NGS) followed by Sanger sequencing. A novel missense mutation in GJA8 (c.T217C) in ADCC patients causes a serine-to-proline substitution at residue 73 of connexin 50 (Cx50); no mutation was found in unaffected family members and unrelated healthy individuals. Functional analysis revealed that this missense mutation disrupts protein function in human lens epithelial cells (HLEpiCs), which fails to form calcium-sensitive hemichannels. Furthermore, mutant Cx50 leads to decreased ROS scavenging by inhibiting G6PD expression and thus induces cell apoptosis via aberrant activation of the unfolded protein response (UPR). In conclusion, we report a novel GJA8 heterozygous mutation in a Chinese family with a vital role in ADCC, broadening the genetic spectrum of this disease.

Comparison of botulinum toxin with surgery for the treatment of acute acquired comitant esotropia and its clinical characteristics.

We compared the therapeutic effects between botulinum toxin and surgery for acute acquired comitant esotropia (AACE) and analyze its clinical characteristics. The data of the 29 cases, who received treatment for AACE in the Ophthalmic Center of the First Affiliated Hospital of Zhengzhou University and Henan Provincial Ophthalmology Hospital between January 2016 and January 2017, were collected. The 29 cases with AACE were followed for 6 months or more, and received either botulinum toxin injection (group A with 13 cases) or squint correction (group B with 16 cases). The distant and near deviation angles were compared between the two groups before and after treatment. The success rate (total horizontal deviation of 10 prism diopters or less) and stereopsis were compared between the two groups at post-treatment 6 months. At the same time, the relations between distant and near deviation angles were analyzed among different myopia levels and different AACE types. Results indicated that he success rate was not significantly different at post-treatment 6 months (84.6% vs 81.3%, P = 1.00). The distant and near deviation angles were all significantly different one day and one month after treatment (all P < 0.05); but at post-treatment 6 months, they were not significantly different (all P > 0.05) between the two groups. There were no significant differences in the distant and near stereoacuity between the two groups at post-treatment 6 months (all P > 0.05). Among the 25 cases with myopia, the pre-treatment distant deviation angle was significantly higher than pre-treatment near deviation angle in the cases with myopia level >-2.5 D (P < 0.05), and the pre-treatment distant and near deviation angles were all significantly higher in the cases with type-IIAACE than in the cases with type-IIIAACE (all P < 0.05). This study suggests that Botulinum toxin is as effective as surgery in the treatment of AACE at post-treatment 6 months. For the cases with myopia level >-2.5 D, the pre-treatment distant deviation angle is significantly higher than pre-treatment near deviation angle; and both pre-treatment distant and near deviation angles are greater in the cases with type-IIAACE than in the cases with type-IIIAACE.

Association between endoplasmic reticulum stress and risk factors of diabetic retinopathy.

Diabetic retinopathy (DR) is one of the most common and challenging ocular complications of diabetes mellitus. As a chronic, progressive ocular disease that poses a serious threat to vision, DR has gradually become a leading cause of blindness worldwide. Emerging evidence points to an important role of endoplasmic reticulum (ER) stress in not only maintaining the steady-state equilibrium in the body, but also in intracellular synthesis, protein folding, and other essential functions. Recent studies have demonstrated clear associations between ER stress-related physiological functions and the pathogenesis of DR. When cells are stimulated by external stimuli, UPR pathway is activated firstly to protect it. However, long-term harmful factors can induce ER stress. which interferes with the physiological metabolism of retinal cells and participates in the occurrence of DR via the ATF6 pathway, PERK pathway and IRE1 pathway. At present, ER stress blocker is expected to become a new anti-DR therapy. Thus, understanding the relationship between ER stress and DR will help to develop new effective preventative treatments. In this review, we summarize the risk factors of DR pathogenesis induced by ER stress toward revealing potentially new therapeutic targets.

Two novel mutations identified in ADCC families impair crystallin protein distribution and induce apoptosis in human lens epithelial cells.

Congenital cataract (CC) is a clinical and genetically heterogeneous eye disease that primarily causes lens disorder and even amblyopic blindness in children. As the mechanism underlying CC is genetically inherited, identification of CC-associated gene mutations and their role in protein distribution are topics of both pharmacological and biological research. Through physical and ophthalmic examinations, two Chinese pedigrees with autosomal dominant congenital cataract (ADCC) were recruited for this study. Mutation analyses of CC candidate genes by next-generation sequencing (NGS) and Sanger sequencing revealed a novel missense mutation in CRYBB2 (p.V146L) and a deletion mutation in CRYAA (p.116_118del). Both mutations fully co-segregated were not observed in unaffected family members or in 100 unrelated healthy controls. The CRYBB2 missense mutation disrupts the distribution of CRYBB2 in human lens epithelial cells (HLEpiCs), and the CRYAA deletion mutation causes hyperdispersion of CRYAA. Furthermore, these two crystallin mutations result in aberrant expression of unfolded protein response (UPR) marker genes as well as apoptosis in HLEpiCs. Collectively, these findings broaden the genetic spectrum of ADCC.

Surgical treatment and visual outcomes of cataract with persistent hyperplastic primary vitreous.

AIM: To evaluate the surgical treatment and visual outcomes of eyes with cataract and persistent hyperplastic primary vitreous (PHPV). METHODS: This retrospective study included patients with cataract and PHPV treated with various strategies. Anterior PHPV was treated using phacoemulsification with underwater electric coagulation on posterior capsule neovascularization, posterior capsulotomy, anterior vitrectomy, and intraocular lens (IOL) implantation. Posterior PHPV was treated with lensectomy, posterior vitrectomy, retinal photocoagulation, and IOL implantation or silicone oil tamponade. Visual acuity (VA), pattern visual evoked potential (P-VEP), anatomic recovery, postoperative complications, and amblyopia outcome were examined. Subjects were followed-up for 3-48mo after surgery. RESULTS: Of the 30 patients (33 eyes) with congenital cataract and PHPV included (average age, 39.30±35.47mo), 9 eyes had anterior PHPV and 24 had posterior PHPV. Thirty-two eyes were surgically treated. Eyes with anterior PHPV received an IOL during one-stage (6 eyes) and two-stage (3 eyes) implantation. Postoperative complications included retinal detachment (1 eye) and recurrent anterior chamber hemorrhage (1 eye). In eyes with posterior PHPV, 6 and 11 eyes received IOLs in one- and two-stage procedures, respectively. Silicone oil was retained in 2 eyes, and IOLs were not implanted in 4 eyes. VA significantly improved in 25 eyes following operations and 3-48mo of amblyopia treatment. P-VEP P100 was improved following surgery in both PHPV types. CONCLUSION: Our surgical strategies are appropriate and effective for anterior and posterior PHPV. Early surgical intervention and amblyopia therapy result in positive treatment outcomes.

Long-term outcomes of wedge resection at the limbus for high irregular corneal astigmatism after repaired corneal laceration.

AIM: To evaluate the clinical value of wedge resection at corneal limbus in patients with traumatic corneal scarring and high irregular astigmatism. METHODS: Patients with traumatic corneal astigmatism received wedge resection at least 6mo after suture removal from corneal wound. The uncorrected distance visual acuities (UCVA) and best corrected distance visual acuities (BCVA), pre- and post-operation astigmatism, spherical equivalent (SE), safety and complications were evaluated. RESULTS: Ten eyes (10 patients) were enrolled in this study. Mean follow-up time after wedge resection was 37.8±15.4mo (range, 20-61mo). The mean UCVA improved from +1.07±0.55 logMAR to +0.43±0.22 logMAR (P=0.000) and the mean BCVA from +0.50±0.30 logMAR to +0.15±0.17 logMAR (P=0.000). The mean astigmatism power measured by retinoscopy was -2.03±2.27 D postoperatively and -2.83±4.52 D preoperatively (P=0.310). The mean SE was -0.74±1.61 D postoperatively and -0.64±1.89 D preoperatively (P=0.601). Two cases developed mild pannus near the sutures. No corneal perforation, infectious keratitis or wound gape occurred. CONCLUSION: Corneal-scleral limbal wedge resection with compression suture is a safe, effective treatment for poor patients with high irregular corneal astigmatism after corneal-scleral penetrating injury. Retinoscopy can prove particularly useful for high irregular corneal astigmatism when other measurements are not amenable.

[Experimental study of TGF-ß2 antisense oligonucleotide on inhibiting corneal scar hyperplasia in rabbits].

OBJECTIVE: To investigate the influence of TGF-ß2 antisense oligonucleotide (ASON) on preventing corneal scar hyperplasia in rabbits and to provide experimental evidence for its clinical application. METHODS: It was an experimental study. One hundred and ninety two New Zealand white rabbits were randomly divided into 4 groups (groups A, B, C and D). Corneal injury models were established in all groups. There were 48 experimental animals in each group. TGF-ß2 ASON was dropped into right eyes in group A, dexamethasone was dropped into right eyes in group B, deionized water was dropped into right eyes in group C and nothing was dropped into right eyes in group D after the operation. The corneas were surgically removed and assessed by hematoxylin eosin (HE) staining, immunohistochemical study and real time PCR at four different time points (4 d, 7 d, 14 d and 28 d) after surgery. RESULTS: HE staining: at the same time point, fibroblasts in the groups A and B were significantly fewer than that in the groups C and D, the difference was statistically significant (P < 0.05), but there was no significant difference between groups A and B or groups C and D. Immunohistochemical observation found that the expression of α-smooth muscle actin (α-SMA) positive fibroblasts could be observed by the 4th day (9.44 ± 0.47/HP), reached a climax by the 7th day (12.50 ± 0.81/HP), and returned to the baseline levels by the 14th day (0.85 ± 0.43/HP) in the group A, which was similar to that in the group B (9.49 ± 0.95, 12.42 ± 0.70, 0.86 ± 0.79/HP) at the same time point (P > 0.05), but it was significantly fewer than that in the group C(20.14 ± 0.78, 18.19 ± 1.28, 4.87 ± 0.58/HP) and group D(20.21 ± 0.92, 18.25 ± 1.39, 5.00 ± 2.217/HP), which was statistical significant (P < 0.05). The staining intensity of fibronectin (FN) in groups A and B was significantly weaker than that in groups C and D. Real time PCR analysis showed that at each time point, the expression of TGF-ß2 mRNAs in groups A and B was significantly lower than that in groups C and D (P < 0.05). CONCLUSIONS: TGF-ß2 ASON can effectively prevent the proliferation of corneal tissue by inhibiting the activity of TGF-ß2 after injury. The early stage of corneal repair is 7 days after injury, so it is important to use TGF-ß2 ASON at this stage to inhibit the scar hyperplasia. In addition, it is safe to apply TGF-ß2 ASON topically to protect the cornea from obvious side effects.

[Evaluation of calcium dobesilate for its anti-cataract potential in experimental rat models].

OBJECTIVE: To investigate the preventive and therapeutic effects of agent calcium dobesilate(CDO) with different doses on the galactose cataract of rats. METHODS: We chose fifty Wistar rats at 20- day old. Then, they were divided into 3 groups at random. Choose 10 rats as the control group and gave normal diet; 10 rats as the model group and fed with Gal solution ( drink 12.5% Gal solution from 1 to 7 days and 10%Gal solution from 8 to 21 days except for normal diet ) ; 30 rats as the treatment group and fed with the same Gal solution as the model group, besides they were divided into high dosage group, medium dosage group and low dosage group equally and gave 300 mg×kg(-1)×d(-1), 150 mg×kg(-1)×d(-1), 75 mg×kg(-1)×d(-1) dose of calcium dobesilate respectively from the first day to the end of experiment. The experiment lasts 21 days. Lens opacity were observed and recorded by slit-lamp examination regularly. Activity of superoxide dismutase (SOD) and glutathione peroxidase (GSH-px) and content of malondialdehyde (MDA) were determined to estimate the effect of CDO . Lens fibers changes and Histological changes were observed by scanning electron microscope (SEM) and light microscope (LM) separately. The apoptosis rate of lens epithelium were determined by TUNEL assay. RESULTS: The appearance of Lens opacity in model group was more quickly than that in treatment group in model group, 3 eyes in degree IV, 7 eyes in degree V, while in treatment group, 5 eyes in degree III, 3 eyes in degree IV, 2 eyes in degree V (H = 7.12, P < 0.05). The activity of SOD and GSH-px in treatment group is higher than mode group, but lower than control group on 8th day, there was difference noticed in the activity of SOD (50.01 ± 1.19), (39.39 ± 1.70) , treatment group (46.57 ± 1.09, 46.42 ± 0.87, 45.70 ± 1.46) U/mgProt (F = 88.70, P < 0.05) and the activity of GSH-px (42.92 ± 0.97) , (12.70 ± 1.17) , treatment group (29.16 ± 1.05, 29.08 ± 0.98, 28.25 ± 0.98) nmol/mgprot (F = 1071.89, P < 0.05) ]in 3 groups. The content of MDA in model group (3.43 ± 0.15)nmol/mgprot is higher than treatment group (2.89 ± 0.11, 2.99 ± 0.12, 2.99 ± 0.09)nmol/mgprot (F = 64.62; P < 0.05). There were no statistic significant differences among high dosage group, medium dosage group and low dosage group . The texture of lens fibres detected by SEM in the rats of model was more disorder than treatment group. After HE staining, Lens epithelial cell detected by LM in control group have a clear structure, however, Lens epithelial cell both in model group and treatment group have changed from the initial single layer to multi-storey. Junction between lenses fibers became decreased even disappeared . The apoptosis rate of lens epithelium in treatment group[(2.37 ± 0.17)%, (2.46 ± 0.26)%, (2.79 ± 0.41)%] is higher than control group (0.23 ± 0.07) %, but is much fewer than model group (4.99 ± 0.51) % (χ(2) = 40.41;P < 0.05). CONCLUSION: CDO with different doses could protect lens of rats against galactose damage and there were no significant differences among the different doses of groups.

[Clinical observation of visual quality after aspherical intraocular lens implantation in traumatic cataract].

OBJECTIVE: To observe the visual quality of aspherical intraocular lens (IOL) implantation in traumatic cataract patients. METHODS: Prospective clinical study.96 traumatic cataract patients (96 eyes) suffered from penetrating corneal trauma chosen from the first affiliated hospital of Zhengzhou university during June 2009 to June 2012. They were divided into two groups based on the different type of intraocular lens. The experimental group (48 eyes) was implanted with aspherical IOL and the control group (48 eyes) was implanted with traditional sphere IOL.Uncorrected visual acuity (UCVA), best corrected visual acuity (BCVA), contrast sensitivity (CS) and stereoscopic vision were observed at 1 month, 3 months, and 6 months after surgery. At the same time, questionnaire survey about the satisfaction of patients was also performed. The t test was used to compare the preoperative general condition, postoperative visual acuity, contrast sensitivity and stereoscopic vision of the two groups, and the rank sum test was used to compare the astigmatism and the satisfaction of patients. RESULTS: There was no significant difference in UCVA (t = 1.37, 1.28,0.71, P > 0.05) between the experimental group (0.56 ± 0.22, 0.68 ± 0.13,0.84 ± 0.15) and the control group (0.51 ± 0.17, 0.61 ± 0.20,0.81 ± 0.17) at three time points. There was no significant difference in BCVA (t = 0.87, 1.38, 1.39, P > 0.05) between the experimental group (0.62 ± 0.13, 0.74 ± 0.21, 0.87 ± 0.10) and the control group (0.57 ± 0.25,0.69 ± 0.22,0.84 ± 0.15) . The same result happened in stereoscopic vision at 6 months after surgery (far stereopsis:123.5 ± 7.8 vs 126. 9 ± 5.9, t = 0.64, P > 0.05;near stereopsis:90.5 ± 7.8 vs 95.2 ± 3.5; t = 1.36, P > 0.05) between experimental group and control group. The contrast sensitivity of the experimental group in every stage (3 c/d:1.52 ± 0.18, 6 c/d:1.68 ± 0.19, 12 c/d:1.29 ± 0.14, 18 c/d:1.04 ± 0.20) was superior to the control group (3 c/d:1.49 ± 0.27, 6 c/d:1.57 ± 0.21, 12 c/d:1.14 ± 0.20, 18 c/d:0.85 ± 0.14) , especially on the glare sensitivity (the experimental group:3 c/d:1.40 ± 0.15, 6 c/d:1.52 ± 0.22, 12 c/d:1.21 ± 0.18, 18 c/d:0.91 ± 0.14, the control group:3 c/d:1.13 ± 0.13, 6 c/d:1.13 ± 0.28, 12 c/d:0.92 ± 0.13, 18 c/d:0.54 ± 0.16) Compared two groups of difference have statistical significance (free from glare:3 c/d:t = 2.829, 6 c/d:t = 4.092, 12 c/d:t = 3.055, 18 c/d:t = 2.093;glare:3 c/d:t = 2.650, 6 c/d:t = 3.105, 12 c/d:t = 3.395, 18 c/d:t = 2.215;P < 0.05) .Questionnaire survey showed the experimental group (72.9%) was statistically significantly higher (t = 3.016, P < 0.05) than that in the control group (54.1%) on the satisfaction of patients. CONCLUSIONS: The visual quality with implantation of aspherical IOL in traumatic cataract patients is superior to traditional sphere IOL. Aspherical IOL is more appropriate for the patients with small and peripheral corneal scar.It can reduce the visual function damage to minimum caused by trauma.

[Quantitative observation on changes of anterior segment by ultrasound biomicroscopy after posterior chamber phakic intraocular lens implantation].

OBJECTIVE: The objective is to study the safety and effectiveness of implantation of posterior chamber phakic intraocular contact lens (ICL) by observing the changes in anterior segment using ultrasound biomicroscopy (UBM). METHODS: It was a perspective study. The study sampled 30 high myopia patients (30 eyes) who were treated with posterior chamber phakic ICL implant. Central anterior chamber depth (ACD), trabecular-iris angle (TIA), angle opening distance (AOD500), trabecular-ciliary processes distance (TCPD) and iris-ciliary processes distance (ICPD) were measured using UBM preoperatively, 3 months and 1 year postoperatively. The distance from ICL to the central surface of lens and peripheral lens and intra-ocular pressure were measured postoperatively and examined using slit-lamp biomicroscope. One-way ANOVA was used to analyze the distance between peripheral surface of ICL and the lens. One-way repeated measures ANOVA and Bonferroni were conducted. RESULTS: Preoperatively, 3 months and 1 year postoperatively, ACD were (3.16±0.08) mm, (2.76±0.13) mm, (2.74±0.14) mm; AOD500 were (0.45±0.04) mm, (0.41±0.04) mm, (0.41±0.03) mm; TIA were (35.00±3.24)°, (32.47±3.56)°, (32.40±3.23)°, respectively. There were significant difference in TIA, ACD and AOD (P<0.05) between preoperative and postoperative data. There was no significant difference between the two postoperative periods tested. TCPD and ICPD showed no significant difference between various time points (F=0.49, F=0.57; P>0.05). CONCLUSIONS: The decrease in ACD depth and correction in TIA and AOD were the noticeable changes observed in morphological structure of the ocular anterior segment after the ICL treatment. The incidence of complication did not increase as the result of the minor changes in morph structure during the course of the study. However, the long-term effects would require further long-term observation.

Contrast sensitivity and higher-order aberrations in patients with astigmatism.

BACKGROUND: Astigmatism is one of the most significant obstacles for achieving satisfactory visual function. This study was to evaluate the influence of astigmatism on contrast sensitivity (CS) and higher-order aberrations. METHODS: CS, accommodation response and wavefront aberration were measured in 113 patients with astigmatism, aged 18 - 36 years. Both single and binocular visual performance were examined under four lighting conditions: photopia, photopia with glare, scotopia and scotopia with glare respectively. Accommodation response was classified as normal, abnormal and low. The contribution of the power and axis of astigmatism to CS, accommodation response and wavefront aberration was analyzed. RESULTS: As the dioptric power of astigmatism increased, the loss of CS spatial frequency changed from high to intermediate, and then to low frequency. CS scores varied at different illuminance levels, descending in the following sequence: photopia, photopia with glare, scotopia, and scotopia with glare. However, the normal accommodation group showed better CS values under photopia with glare than without glare. The range of influenced direction of sine-wave gratings remained mostly at the meridian line of high dioptric power, which would be expanded when optical accommadation attenuated. The patients with symmetrical astigmatism got higher CS scores with binoculus vision than with dominant eye vision, while the patients with asymmetrical astigmatism did this only at scotopia with glare. Among higher-order aberrations, coma aberration, secondary coma aberration and the total higher order aberration were influenced by astigmatism, all of which rising with the power of astigmatism increased. CONCLUSIONS: Reducing astigmatism might improve the performance of visual function. Not only the power of astigmatism should be cut down, but also the binocular axes should be made symmetrically.

[Tissue culture of bovine lens as an in vitro model for posterior capsule opacification and the effects of pranoprofen on the cell confluence].

OBJECTIVE: To establish an in vitro model of posterior capsule opacification (PCO) by culturing the posterior capsule of bovine lens, to observe the proliferation and differentiation of lens epithelial cells and to study the influence of serum and pranoprofen eyedrops on cell confluence of this model. METHODS: The bovine lens posterior capsule was spread on the surface of a 25 ml culture flask with cell layer upward. DMEM with 0%, 10% and 20% fetal calf serum was used as culture medium. The cell coverage and confluence time on the posterior capsule were observed by inverted microscope and the cell morphology was observed by Giemsa staining and scanning electron-microscope. Pranoprofen was added to the culture medium at a concentration similar to the aqueous humor concentration (0.23 mg/L), which was presented at 4 hours after the instillation of pranoprofen eyedrops. The difference of confluence time between the treated group and the control group was compared. RESULTS: The lens epithelial cells migrated and proliferated rapidly on the posterior capsule from the equatorial region to the center. The cell coverage was increased and the confluence time was shortened with the increase of serum concentration (P < 0.05). The PCO and wrinkles were presented. Pranoprofen at 0.23 mg/L could inhibit the confluence of lens epithelial cells (P < 0.01). CONCLUSIONS: The in vitro model for PCO was an useful method to study the mechanism of PCO formation. Pranoprofen can inhibit the proliferation of lens epithelial cells and is a safe and efficient drug for preventing the occurrence of PCO and can be used as a routine medication after the cataract operation.

Early activation of caspase-1 after retinal ischemia and reperfusion injury in mice.

BACKGROUND: Caspases are important in the signaling pathway of cellular apoptosis. Caspase-3 protein expression has been shown to increase and parallel to neuronal apoptosis in retinal ischemia injury. This study was to determine whether caspase-1 is involved in neuronal cell death or in retinal ischemia and reperfusion injury. METHODS: In twenty-one adult mice, ischemia was induced by increasing the intraocular pressure. The animals were sacrificed at 1 hour, 3 hours, 6 hours, 1 day, 3 days and 7 days after reperfusion. Frozen sections were used for caspase-1 immunostaining and TUNEL labeling. RESULTS: In normal retina, no caspase-1 positive cells were seen. One hour after ischemia, numerous positive cells were noted in the ganglion cell layer (GCL) and inner side of inner nuclear layer (INL). At 3 hours, caspase-1 positive cells continued to increase and peaked at 6 hours, then decreased significantly at 1 day. TUNEL positive cells were detected at 3 hours and peaked at 1 day after ischemia. Double labeling of caspase-1 and TUNEL only showed few cells with co-localization after ischemia. CONCLUSION: Caspase-1 immunoreactivity preceds to the TUNEL labeling in the GCL and INL after retinal ischemia and reperfusion injury and its early activation may play an important role in the initiation of neuronal apoptosis.