Case of Spontaneous Closure and Recurrence of Macular Hole in Vitrectomized Eye.

Rationale: Development and spontaneous closure of a macular hole (MH) in a vitrectomized eye is relatively rare. We report our findings in a case in which vitrectomy was performed successfully to treat a vitreous hemorrhage (VH), but a MH developed eight months later. The MH spontaneously closed 2 weeks later, but then reopened. A second vitrectomy was performed with insertion of the internal limiting membrane flap into the MH which led to the successful closure of the MH. The purpose of this article is to present an explanation of how MH developed in this eye without vitreous traction. Patient: A 64-year-old woman visited an eye clinic with vision reduction in her right eye of 3 days duration. A VH was detected in the right eye and pars plana vitrectomy (PPV) was performed. A retinal tear was detected which was the origin of the VH. The vision was restored to a decimal visual acuity of 1.2. Eight months later, the patient noticed that her vision was distorted and was referred to our hospital. Diagnosis: Optical coherence tomographic (OCT) images showed a thin epiretinal membrane on the macula, cystoid changes in the macular area, and a full-thickness MH. Interventions: The MH closed spontaneously in two weeks, however a lamellar MH with an epiretinal proliferation (EP) developed 11 months later. Two months later, OCT showed cyst-like changes in the retina and a full-thickness MH. A second PPV was performed with the insertion of the ILM flap and EP into the MH to close the MH. Her visual acuity improved, and distorted vision was not present. Lessons: Clinicians should be aware that a MH can develop in a vitrectomized eye without vitreous traction but can close spontaneously. We conclude that careful follow-up examinations are necessary even in vitrectomized eyes.

Electroretinographic and Optical Coherence Tomographic Evaluations of Eyes with Vitreoretinal Lymphoma.

Vitreoretinal lymphomas (VRLs) present with different clinical characteristics. However, only a few case reports have been published that evaluated the retinal function and the retinal morphology. The relationship between retinal morphology and function of eyes with a vitreoretinal lymphoma (VRL) was investigated via optical coherence tomography (OCT) and electroretinography (ERG). The ERG and OCT findings in 11 eyes of 11 patients (69.4 ± 11.5 years old) who were diagnosed with VRL at the Saitama Medical University Hospital between December 2016 to May 2022 were studied. The decimal best-corrected visual acuity ranged from hand movements to 1.2 (median 0.2). Histopathological studies of the vitreous specimens showed class II VRL in one eye, class III VRL in seven eyes, class IV VRL in two eyes, and class V VRL in one eye. The IgH gene rearrangement was positive in three of the six eyes tested. The OCT images showed morphological abnormalities in 10 of the 11 (90.9%) eyes. Severe attenuation was found for the amplitudes of the b-wave of the DA 0.01 ERG in 6 of 11 eyes (54.5%), the DA 3.0 a-wave in 5 of 11 eyes (45.5%), the DA 3.0 b-wave in 36.4%, the LA 3.0 a-wave in 36.4%, the LA 3.0 b-wave in 18.2%, and flicker responses in 36.4% of the eyes. None of the DA 3.0 ERGs had a negative shape (b/a < 1.0). In the five eyes in which the a-wave was severely attenuated, hyperreflective dots were observed subretinally. The ERG analysis in eyes with a VRL indicates a relatively severe dysfunction of the outer retinal layer and was helpful in determining the site of the morphological changes in eyes with VRL.

Evaluation of macular visibility through a high-order aspheric intraocular lens using a simulated model eye.

We evaluated the macular visibility of a newly designed extended depth of focus (EDOF) intraocular lenses (IOL) using a wide viewing system for macular manipulation (Risight;60D, Carl Zeiss Meditec AG) in a model eye and compared it with various other types of IOLs. We used a model eye that was constructed based on the Glustrand model to compare a newly designed EDOF IOL (DIB00V; Johnson & Johnson Surgical Vision), an EDOF IOL with a diffraction grating (ZXR00V; Johnson & Johnson surgical Vision), and a monofocal aspheric (DCB00V; Johnson & Johnson Vision, XY-1; HOYA Surgical Optics, Tokyo, Japan) or spherical IOL (NX70s; Santen Pharmaceutical Co., Ltd). In the model eye, a 1951 United States Air Force (USAF) test was placed at the location of the macula. The contrasts in a range of spatial frequencies were quantified using the images obtained from the 1951 USAF test target. The contrast at each spatial frequency was plotted and integrated to calculate the area under the curve contrast (AUC-contrast). Qualitative evaluations showed that good-quality images were obtained for all IOLs. At a spatial frequency of 16 LP/mm, the average contrast was the highest for the DIB00V and NX70s (0.216 each). The highest average contrast at 32 LP/mm was obtained using the NX70s (0.128), and at 64 LP/mm using the DIB00V (0.123). The horizontal AUC-contrast was the highest for the NX70s (8.754), and the vertical AUC-contrast was the highest for the DIB00V (8.334). On average, the DIB00V had the highest AUC-contrast value (8.227). The high-order aspheric IOL, DIB00V, was found to exhibit good macular visibility despite being an EDOF IOL.

A Case of Intraocular Lymphoma Diagnosed by Subretinal Fluid Biopsy.

Although intraocular lymphoma (IOL) mainly has have vitreous opacity and subretinal infiltration, its clinical symptoms are diverse. We report a case of IOL that mainly showed exudative retinal detachment in which analysis of IgH gene rearrangement (AIGHR) of the collected subretinal fluid sample was useful for diagnosis. A 77-year-old woman developed decreased left visual acuity for 1 month. She had been treated for dermatomyositis, diabetes mellitus, and right parotid tumor for 3 years. Visual acuity was 0.1 OD and counting fingers OS. Slit-lamp examination showed grade 4 (Emery-Little classification) nuclear cataract in both eyes and keratoprecipitates and tan vitreous opacity in the left eye. Fundoscopy details were unclear except for a vaguely observable optic nerve head due to yellow-brown vitreous opacity, which we judged as an old vitreous hemorrhage. Phacovitrectomy was performed and almost total retinal detachment was found, except for a part of the superior periphery. Since no retinal break was found and a wide range of thin membrane-like tissue was found on the surface of the retina, the surgeon suspected primary IOL and performed unplanned biopsy. The peripheral vitreous was collected as a sample, and then the subretinal fluid was collected through an intentional break to prevent mixing with other fluids. The subretinal strand was gently removed and collected. Cytology showed class III, the IL10/IL6 ratio was low, and AIGHR was positive. Postoperatively, fundus autofluorescence showed no abnormality, no leakage was observed on fluorescein and indocyanine green angiography, and the location of typical infiltration lesions under the retina was unclear. There were no positive findings on systemic examinations and a diagnosis of primary IOL was made. The main symptoms of this case were vitreous opacity and exudative retinal detachment, and AIGHR using subretinal fluid was useful for diagnosis.

Noninferiority of Microhook to Trabectome: Trabectome versus Ab Interno Microhook Trabeculotomy Comparative Study (Tram Trac Study).

PURPOSE: To elucidate the noninferiority of ab interno microhook trabeculotomy (µTLO) using a recently developed reusable stainless spatula-type microhook device to incise the trabecular meshwork to Trabectome (Neomeix, Inc) surgery in terms of the 1-year postoperative outcomes of Japanese patients with glaucoma by means of propensity score analyses. DESIGN: Multicenter, retrospective cohort study. PARTICIPANTS: We enrolled 553 and 392 patients who underwent Trabectome surgery and µTLO, respectively, between January 2014 and March 2020 at 10 facilities. METHODS: Logistic regression analysis was conducted to calculate the propensity score, which indicates the likelihood of treatment assignment (Trabectome or µTLO). We set the following factors as outcome-related covariates: age, sex, facility, glaucoma disease types, preoperative intraocular pressure (IOP), glaucoma drug score, mean deviation of Humphrey visual field test results, antithrombotic drug use, the presence or absence of combined cataract surgery, and incision range of the trabecular meshwork (1 or 2 quadrants). We analyzed 4 different methods (matching, inverse probability of treatment weighting [IPTW], stratification, and regression adjustment) using the propensity score. We set 15% as the noninferiority margin based on previous Trabectome meta-analysis results. MAIN OUTCOME MEASURES: The primary outcome was surgical success at 1 year after surgery. We defined surgical success as satisfying all 3 criteria: (1) IOP within 5 to 21 mmHg, (2) IOP reduction of 20% or more from preoperative IOP, and (3) no additional glaucoma surgery. RESULTS: The 95% confidence interval of risk difference of surgical failure in µTLO in reference to Trabectome surgery was -12.1% to +9.5% in matching, -12.7% to +11.1% in IPTW, -12.2 to +7.0 in stratification, and -9.7% to +8.1% in regression adjustment, all of which fell within the predetermined noninferiority margin of 15%. CONCLUSIONS: Surgical success of µTLO at 1 year after was not inferior to that of Trabectome surgery.

Quantitative assessment of macular function after surgery for optic disc pit maculopathy: A case report.

RATIONALE: We describe a case of optic disc pit maculopathy (ODP-M) in which vitrectomy with juxtapapillary laser (JPL) treatment led to the reattachment of retinoschisis (RS) as well as serous retinal detachment (SRD). PATIENT CONCERNS: An 80-year-old man complained of distorted vision and decreased visual acuity (VA) in his left eye for 12 months. DIAGNOSIS: We conducted quantitative functional evaluation on the area of RS and SRD using the Humphrey visual field analyzer. Fundus examination and optical coherence tomography showed SRD and RS in connection with the optic disc. The best-corrected logarithm of the minimum angle of resolution (logMAR) VA was 0.7. INTERVENTIONS: The patient underwent JPL treatment combined with pars plana vitrectomy. During surgery, posterior vitreous detachment and tamponade were created with sulfur hexafluoride. OUTCOMES: After surgery, SRD (and subsequently RS) gradually reduced and had completely disappeared at 31 months. VA gradually improved and was 0.0 (logMAR) at 28 months. The analysis of the mean macular thickness of the central 3-mm diameter showed that the macula thickness recovered to 300 µm at 17 months postoperatively. Retinal sensitivity began to improve at 24 months postoperatively and had increased at 48 months postoperatively. LESSONS: In conclusion, vitrectomy with JPL treatment for ODP-M had a favorable anatomical outcome as well as a long-term functional outcome. These findings provide useful information for clinicians who are planning a therapeutic strategy, including the choice of surgical procedure for ODP-M.

Development and spontaneous closure of a secondary macular hole associated with submacular hemorrhage due to polypoidal choroidal vasculopathy: a case report.

BACKGROUND: Macular hole (MH) is a retinal break in the fovea involving partial or complete dehiscence of the neural retinal layers affecting the visual quality by decreasing visual acuity (VA) and visual deformation. We describe a case of secondary MH associated with submacular hemorrhage (SMH) due to polypoidal choroidal vasculopathy (PCV), which showed spontaneous closure. CASE PRESENTATION: A 67-year-old man developed decreased VA in his right eye due to an SMH. The VA was 20/50, and monthly intravitreal injection of aflibercept was administered three times. The SMH gradually decreased, and 10 months later the external limiting membrane was found to be perforated, resulting in MH. The old clot disappeared, and the MH remained for 10 months. Twenty-three months later, serous retinal detachment (SRD) involving the macula appeared and the MH had disappeared. SRD gradually disappeared, and macular configuration recovered. VA gradually improved and became 20/20 38 months later. CONCLUSION: Dynamic change of the ultrastructure in an unusual case of secondary-developed and spontaneously closed MH was clearly observed. Although the mechanism was unknown, the small diameter size and exudative PCV are thought to have contributed to the closure.

Heads-Up 3D Surgery under Low Light Intensity Conditions: New High-Sensitivity HD Camera for Ophthalmological Microscopes.

PURPOSE: To determine the feasibility of performing intraocular surgeries in a heads-up position with low illuminance conditions by observing a display of the surgical field created by a three-dimensional imaging (3D) system. METHODS: Seventy-four eyes of 56 patients underwent cataract surgery (72 eyes) with the heads-up 3D surgery system; 60 eyes with cataract surgery alone, 7 eyes with combined cataract and glaucoma microdevice implant surgery, 5 eyes with combined cataract and vitrectomy surgery, and two eyes with vitrectomy surgery alone were studied. The illuminance from the surgical microscope was set to be dimmer (Leica M822F40 main light 2%; otto-flex 6%) than the usual setting to minimize the discomfort and glare for the patient. The surgeries were performed under topical anesthesia. The luminance of the images observed through the eyepieces of the operating microscope and the image of a 3D system created by a high-sensitivity sensor Exmor R 3CMOS HD camera (Sony MCC-1000MD) were measured. RESULTS: All surgeries were completed without any complications under the low illumination conditions. The surgical field on the display monitor was created by a 3D system using a high-sensitivity sensor camera and was observed in a heads-up position. The patients did not report any intolerable discomfort or glare during the surgery. Cataract surgeries were performed with a good view of the surgical field under the extremely low illumination from the surgical microscope. The high-sensitivity sensors and electronic amplifications of the image signals made the surgical field brighter and allowed the surgeon to perform the surgery confidently and safely. CONCLUSIONS: Heads-up, 3D-assisted intraocular surgeries can be performed safely and efficiently with low illuminance of the surgical field. This trial is registered with UMIN000037838.

Influence of sclerotomy size on intraocular lens tilt after intrascleral intraocular lens fixation.

PURPOSE: To determine whether differences in sclerotomy size during intrascleral intraocular lens (IOL) fixation influence IOL tilt and visual acuity after surgery. SETTING: University of Fukui Hospital and Japanese Red Cross Fukui Hospital, Japan. DESIGN: Retrospective case series. METHODS: The study reviewed the records of patients who had intrascleral IOL fixation with transconjunctival 25-gauge pars plana vitrectomy and a follow-up longer than 6 months. The preoperative and postoperative visual outcomes, degree of IOL tilt, and intraoperative and postoperative complications were statistically compared between the sclerotomy groups. RESULTS: The study included 65 eyes (60 patients). Postoperatively, the maximum degree of IOL tilt was significantly smaller in the 24-gauge sclerotomy group than in the 30-gauge sclerotomy group (P = .003). The degree of IOL tilt was significantly correlated with the amount of postoperative IOL astigmatism (total astigmatism - corneal astigmatism) (P = .0001, R2 = 0.23). There were no statistically significant differences in the preoperative or postoperative corrected distance visual acuity (CDVA) or the complication rate between the sclerotomy groups. CONCLUSION: A smaller sclerotomy for intrascleral IOL fixation was associated with greater IOL tilt and IOL astigmatism after surgery; however, this did not clinically or significantly affect the postoperative CDVA.

Macular Structure Recovery after Surgery for Optic Disc Pit Maculopathy.

The present report aimed to describe the macular structure's recovery process in a case of optic disc pit maculopathy (ODP-M) with outer layer hole following pars plana vitrectomy (PPV) with juxtapapillary laser treatment (JPL). We performed repeated optical coherence tomography (OCT) examinations to evaluate the macular structural changes. An 80-year-old man presented with distorted vision and decreased visual acuity (VA) in his left eye, experienced for 1 year, prior to presentation. Fundus examination and OCT showed intraretinal fluid (IRF) in the inner and outer retinal layers. Serous retinal detachment (SRD) with an outer layer hole in the macula was also evident. The IRF was connected to the optic disc; however, the SRD was isolated. Best-corrected VA was 20/100. PPV combined with JPL was performed. Posterior vitreous detachment creation and tamponade with sulfur hexafluoride was performed. Postoperatively, the inner retinal IRF at the fovea disappeared. The outer layer hole gradually closed and had completely disappeared 1 month postoperatively. After resolution of the outer layer hole, SRD reduced gradually and disappeared 8 months postoperatively, although the macular outer retinal IRF remained. The outer retinal IRF had partially resolved by the 18th postoperative month. Macular structure was completely recovered 31 months postoperatively, with an improved VA of 20/20. In conclusion, SRD might be associated with outer retinal IRF and outer layer holes. In cases of ODP-M, outer layer holes might induce optic disc-isolated SRD.

Novel transgenic mouse models develop retinal changes associated with early diabetic retinopathy similar to those observed in rats with diabetes mellitus.

Retinal capillary pericyte degeneration has been linked to aldose reductase (AR) activity in diabetic retinopathy (DR). Since the development of DR in mice and rats has been reported to differ and that this may be linked to differences in retinal sorbitol levels, we have established new murine models of early onset diabetes mellitus as tools for investigating the role of AR in DR. Transgenic diabetic mouse models were developed by crossbreeding diabetic C57BL/6-Ins2(Akita)/J (AK) with transgenic C57BL mice expressing green fluorescent protein (GFP), human aldose reductase (hAR) or both in vascular tissues containing smooth muscle actin-α (SMAA). Changes in retinal sorbitol levels were determined by HPLC while changes of growth factors and signaling were investigated by Western Blots. Retinal vascular changes were quantitatively analyzed on elastase-digestion flat mounts. Results show that sorbitol levels were higher in neural retinas of diabetic AK-SMAA-GFP-hAR compared to AK-SMAA-GFP mice. AK-SMAA-GFP-hAR mice showed induction of the retinal growth factors VEGF, IGF-1, bFGF and TGFß, as well as signaling changes in P-Akt, P-SAPK/JNK, and P-44/42 MAPK. Increased loss of nuclei per capillary length and a significant increase in the percentage of acellular capillaries presented in 18 week old AK-SMAA-GFP-hAR mice. These changes are similar to those observed in streptozotocin-induced diabetic rats. Retinal changes in both mice and rats were prevented by inhibition of AR. These studies confirm that the increased expression of AR in mice results in the development of retinal changes associated with the early stages of DR that are similar to those observed in rats.

Novel diabetic mouse models as tools for investigating diabetic retinopathy.

OBJECTIVE: Mouse models possessing green fluorescent protein (GFP) and/or human aldose reductase (hAR) in vascular tissues have been established and crossed with naturally diabetic Akita mice to produce new diabetic mouse models. RESEARCH DESIGN AND METHODS: Colonies of transgenic C57BL mice expressing GFP (SMAA-GFP), hAR (SMAA-hAR) or both (SMAA-GFP-hAR) in vascular tissues expressing smooth muscle actin were established and crossbred with C57BL/6-Ins2(Akita)/J (AK) mice to produce naturally diabetic offspring AK-SMAA-GFP and AK-SMAA-GFP-hAR. Aldose reductase inhibitor AL1576 (ARI) was administered in chow. Retinal and lenticular sorbitol levels were determined by HPLC. Retinal functions were evaluated by electroretinography (ERGs). Growth factor and signaling changes were determined by Western Blots using commercially available antibodies. Retinal vasculatures were isolated from the neural retina by enzymatic digestion. Flat mounts were stained with PAS-hematoxylin and analyzed. RESULTS: Akita transgenics developed DM by 8 weeks of age with blood glucose levels higher in males than females. Sorbitol levels were higher in neural retinas of AK-SMAA-GFP-hAR compared to AK-SMAA-GFP mice. AK-SMAA-GFP-hAR mice also had higher VEGF levels and reduced ERG scotopic b-wave function, both of which were normalized by AL1576. AK-SMAA-GFP-hAR mice showed induction of the retinal growth factors bFGF, IGF-1, and TGFß, as well as signaling changes in P-Akt, P-SAPK/JNK and P-44/42 MAPK that were also reduced by ARI treatment. Quantitative analysis of flat mounts in 18 week AK-SMAA-GFP-hAR mice revealed increased loss of nuclei/capillary length and a significant increase in the percentage of acellular capillaries present which was not seen in AK-SMAA-GFP-hAR treated with ARI. CONCLUSIONS/SIGNIFICANCE: These new mouse models of early onset diabetes may be valuable tools for assessing both the role of hyperglycemia and AR in the development of retinal lesions associated with diabetic retinopathy.

Orally active multi-functional antioxidants delay cataract formation in streptozotocin (type 1) diabetic and gamma-irradiated rats.

BACKGROUND: Age-related cataract is a worldwide health care problem whose progression has been linked to oxidative stress and the accumulation of redox-active metals. Since there is no specific animal model for human age-related cataract, multiple animal models must be used to evaluate potential therapies that may delay and/or prevent cataract formation. METHODS/PRINCIPAL FINDINGS: Proof of concept studies were conducted to evaluate 4-(5-hydroxypyrimidin-2-yl)-N,N-dimethyl-3,5-dioxopiperazine-1-sulfonamide (compound 4) and 4-(5-hydroxy-4,6-dimethoxypyrimidin-2-yl)-N,N-dimethyl-3,5-dioxopiperazine-1-sulfonamide (compound 8), multi-functional antioxidants that can independently chelate redox metals and quench free radicals, on their ability to delay the progression of diabetic "sugar" cataracts and gamma radiation-induced cataracts. Prior to 15 Gy of whole head irradiation, select groups of Long Evans rats received either diet containing compound 4 or 8, or a single i.p. injection of panthethine, a radioprotective agent. Compared to untreated, irradiated rats, treatment with pantethine, 4 and 8 delayed initial lens changes by 4, 47, and 38 days, respectively, and the average formation of posterior subcapsular opacities by 23, 53 and 58 days, respectively. In the second study, select groups of diabetic Sprague Dawley rats were administered chow containing compounds 4, 8 or the aldose reductase inhibitor AL1576. As anticipated, treatment with AL1576 prevented cataract by inhibiting sorbitol formation in the lens. However, compared to untreated rats, compounds 4 and 8 delayed vacuole formation by 20 days and 12 days, respectively, and cortical cataract formation by 8 and 3 days, respectively, without reducing lenticular sorbitol. Using in vitro lens culture in 30 mM xylose to model diabetic "sugar" cataract formation, western blots confirmed that multi-functional antioxidants reduced endoplasmic reticulum stress. CONCLUSIONS/SIGNIFICANCE: Multi-functional antioxidants delayed cataract formation in two diverse rat models. These studies provide a proof of concept that a general cataract treatment focused on reducing oxidative stress instead of a specific mechanism of cataractogenesis can be developed.

Response of rat retinal capillary pericytes and endothelial cells to glucose.

AIM: The purpose of this study was to investigate the effects of hyperglycemia, its fluctuations, and glucose starvation on the expression of glucose-regulated protein 78/binding immunoglobulin protein (GRP78/BiP), one of the most commonly used markers of endoplasmic reticulum stress, in rat capillary pericytes and endothelial cells cultured separately and together. METHODS: Conditionally immortalized rat retinal pericyte and endothelial cell lines were cultured in dishes coated with collagen type I in Dulbecco's modified Eagle's medium containing 5.5 mM glucose. For cocultures, pericytes and endothelial cells were seeded together on rat tail collagen type I-coated cell culture plates. After 24 h of initial culture, the medium was replaced with serum-free medium containing 0-100 mM glucose for periods of up to 72 h. GRP78/BiP, caspase-3, and nuclear factor-κB expression were investigated using western blots. RESULTS: No significant increase in GRP78/BiP expression was observed when pericytes, endothelial cells, or cocultures were exposed to either 25, 50, or 100 mM glucose for 48 h compared with the control level of 5.5 mM glucose. Similarly, no change in expression of GRP78/BiP was observed when media glucose levels were reduced from either 5.5 or 25 to 1 mM. GRP78/BiP expression significantly increased when cells were cultured for 24 h in glucose-deprived medium. This was accompanied by a time-dependent increase in the expression of caspase-3 and nuclear factor-κB. CONCLUSION: In diabetic retinopathy, hyperglycemia has been reported to induce apoptosis in retinal capillary vascular cells, but these studies suggest that the apoptosis is not linked to the expression of GRP78/BiP, one of the most commonly used markers of endoplasmic reticulum stress. However, GRP78/BiP-linked apoptosis may play a role in vascular changes associated with retinal ischemia/reperfusion.

Polyol formation in cell lines of rat retinal capillary pericytes and endothelial cells (TR-rPCT and TR-iBRB).

PURPOSE: The two most widely investigated animal models for diabetic retinopathy (DR) are the rat and dog. In dogs, aldose reductase (AR) is present only in retinal capillary pericytes and their destruction has been linked to polyol accumulation and resulting apoptosis. Since both rat capillary pericytes and endothelial cells have been reported to contain AR, the role of polyol pathway activity in capillary cell destruction has been investigated in rat retinal capillary pericyte (TR-rPCT) and endothelial (TR-iBRB) cells. METHODS: TR-rPCT and TR-iBRB cell lines were recloned and their identities were reconfirmed by characteristic immunostaining. Cells were cultured up to 72 h in media containing 50 mM glucose or galactose with/without the AR inhibitors or a sorbitol dehydrogenase inhibitor (SDI) or with 30 mM 3-fluoro-3-deoxyglucose. Polyol levels were determined by HPLC or (19)F-NMR. Apoptosis was detected with TUNEL/DAPI staining. RESULTS: Smooth muscle actin is present only in pericytes while only endothelial cells stain for von Willebrand factor and accumulate acetylated low-density lipoprotein. AR is present in both cells but AR levels are lower in endothelial cells. Aldehyde reductase is also present in both cells. Cells cultured in 50 mM glucose or galactose show significant polyol accumulation in pericytes but endothelial cells show little accumulation of galactitol and no accumulation of sorbitol. Sorbitol accumulation in pericytes resulted in increased cellular permeability and increased TUNEL staining, which was reduced by AR inhibition. CONCLUSIONS: Although both rat retinal pericytes and endothelial cells contain AR, sorbitol accumulation and TUNEL staining primarily occur in pericytes and are inhibited by AR inhibitors.

Evaluation of the vascular targeting agent combretastatin a-4 prodrug on retinal neovascularization in the galactose-fed dog.

PURPOSE: Combretastatin A-4 (CA-4) is a vascular targeting agent known to rapidly shut off blood flow in new vessels and, as a result, regress neovascularization. In this pilot study, the ability of CA-4 to modify retinal neovascularization, which results in altered retinal vessel blood flow and retinal permeability, was evaluated in aphakic long-term galactose-fed beagles, an animal model that develops diabetes-like retinal neovascularization. METHODS: Two (2) groups of aphakic dogs, each group comprised of 4 galactose-fed dogs and 2 age-matched controls dogs, were utilized. Each group initially received the combretastatin A-4-phosphate prodrug (CA-4P) as either sub-Tenon's injections, administered at the corneoscleral junction, or intravitreal injections. Six (6) weeks after this treatment, all dogs also received systemic (intravenous) injections of CA-4P. Retinal vascular changes were monitored at 2-week intervals by fluorescein angiography. RESULTS: All galactose-fed dogs demonstrated the presence of retinal neovascular lesions by fluorescein angiograms. Fluorescein leakage or perfusion through neovascular vessels was not altered by either sub-Tenon's, intravitreal, or systemic CA-4P administration. Whereas CA-4P was well tolerated by the healthy eyes of the control animals, its administration to some galactose-fed dogs was associated with corneal edema and increases in intraocular pressure following sub-Tenon's and intraocular injections. CONCLUSIONS: Neovascularization in the galactose-fed dog progresses over a period of years, similar to that observed with clinical diabetic retinopathy. The failure of CA-4P to ameliorate neovascularization suggests that chronic, long-term administration may be required to destroy the slowly growing retinal endothelial cells.

Functional gene expression analysis uncovers phenotypic switch in aggressive uveal melanomas.

Microarray gene expression profiling is a powerful tool for generating molecular cancer classifications. However, elucidating biological insights from these large data sets has been challenging. Previously, we identified a gene expression-based classification of primary uveal melanomas that accurately predicts metastatic death. Class 1 tumors have a low risk and class 2 tumors a high risk for metastatic death. Here, we used genes that discriminate these tumor classes to identify biological correlates of the aggressive class 2 signature. A search for Gene Ontology categories enriched in our class-discriminating gene list revealed a global down-regulation of neural crest and melanocyte-specific genes and an up-regulation of epithelial genes in class 2 tumors. Correspondingly, class 2 tumors exhibited epithelial features, such as polygonal cell morphology, up-regulation of the epithelial adhesion molecule E-cadherin, colocalization of E-cadherin and beta-catenin to the plasma membrane, and formation of cell-cell adhesions and acinar structures. One of our top class-discriminating genes was the helix-loop-helix inhibitor ID2, which was strongly down-regulated in class 2 tumors. The class 2 phenotype could be recapitulated by eliminating Id2 in cultured class 1 human uveal melanoma cells and in a mouse ocular melanoma model. Id2 seemed to suppress the epithelial-like class 2 phenotype by inhibiting an activator of the E-cadherin promoter. Consequently, Id2 loss triggered up-regulation of E-cadherin, which in turn promoted anchorage-independent cell growth, a likely antecedent to metastasis. These findings reveal new roles for Id2 and E-cadherin in uveal melanoma progression, and they identify potential targets for therapeutic intervention.

Identification of the nuclear export signal in the helix-loop-helix inhibitor Id1.

Id proteins play important roles in cellular differentiation and proliferation by negatively regulating basic helix-loop-helix transcription factors. Although their intracellular localization may change depending on the biological situation, little is known about the molecular determinants underlying such changes. Here we report the identification of a nuclear export signal (NES) in Id1. The identified NES was different from that of Id2, but had the ability to confine heterologous green fluorescent protein to the cytoplasm. Thus, our results indicate that the intracellular localization of Id1 is regulated differently from that of Id2.