I.–B. Kim

Lycium Barbarum Polysaccharides Protects Retina From Ischemia/Reperfusion Injury

PURPOSE The effects of small interfering (si)RNA of nuclear factor kappa B (NF-kappaB) on the development of posterior capsule opacification (PCO) were investigated both in vitro and in vivo in rabbits. METHODS After application of p105 NF-kappaB siRNA to lens epithelial cells (LECs), Western blot analyses were performed to detect p105 and p50 NF-kappaB and a scratch assay was used to determine cell migration. In the capsular bag model, immunocytochemistry was performed to determine expression of p50 NF-kappaB and Western blot analyses for the presence of epithelial-to-mesenchymal transition (EMT) markers. Two sequences of p105 NF-kappaB siRNA were used in cataract surgery in 15 New Zealand White rabbits. PCO grading was conducted by slit lamp biomicroscopy and a computer-based PCO grading program. One month after surgery, the eyes of the rabbits were enucleated, and sections were prepared for examination of the posterior capsule and other ocular tissues by light microscopy. RESULTS Application of p105 NF-kappaB siRNA to LECs decreased p105 NF-kappaB and p50 NF-kappaB expression, and migration of LECs was shown to be inhibited on the scratch assay. In the capsular bag model, the LEC count was significantly decreased, and immunocytochemistry showed reduced p50 NF-kappaB expression on the posterior capsule. EMT markers were significantly decreased after application of p105 NF-kappaB siRNA in the capsular bag model. In the in vivo study in rabbits, p105 NF-kappaB siRNA effectively decreased PCO, as determined by both slit lamp examination and the PCO grading program. CONCLUSIONS NF-kappaB seems to be related to migration and proliferation of LECs. NF-kappaB siRNA was effective in inhibiting the migration and proliferation of LECs in vitro and decreased PCO formation after cataract surgery in an in vivo rabbit model.

Anti-Angiogenic Effect of KR-31831 on Corneal and Choroidal Neovascularization in Rat Models

PURPOSE We attempt to determine the effect and mechanism of KR-31831 in rat models of corneal neovascularization and choroidal neovascularization (CNV). METHODS Corneal neovascularization was induced by silver nitrate cauterization. Balanced salt solution (for control), KR-31831 (0.1 mg/mL), and bevacizumab (10 mg/mL) were applied topically with or without subsequent subconjunctival injection (10 μL). The degree of corneal neovascularization was compared among treatments. The effects of intravitreal (0.1 and 0.3 mg/mL) and intraperitoneal (25 mg/kg) of KR-31831, and intravitreal injection of bevacizumab (2.5 mg/mL) were compared in a laser-induced CNV model. FITC-dextran was used to observe the choroid vessels and to evaluate vessel leakage by fluorescence intensity. RESULTS In the silver nitrate cauterized rat, topical KR-31831 (P = 0.008) or bevacizumab (P = 0.008) reduced effectively the area of corneal neovascularization compared to control on day 14. This was reduced further by additional subconjunctival injection of KR-31831 (P = 0.024) and bevacizumab (P = 0.016). After KR-31831 application, vascular endothelial growth factor (VEGF) receptor 2 and matrix metalloproteinase (MMP)-2 expression was decreased in the cornea. In the CNV model, intravitreal (0.3 mg/mL) and intraperitoneal KR-31831 inhibited significantly the CNV area (P = 0.008 and P = 0.008, respectively) and fluorescence leakage (P = 0.008 and P = 0.032, respectively). This effect was more significant compared to intravitreal bevacizumab in terms of the CNV area (P = 0.032 and P = 0.008, respectively) and fluorescence leakage (P = 0.016 and P = 0.008, respectively). CONCLUSIONS The anti-angiogenic effect of KR-31831 was comparable in the cornea and more effective in the choroid compared to that of bevacizumab, and it may exert its effect by VEGF signaling and MMP-2.

Postoperative Astigmatic Outcomes Based on the Haptic Axis of Intraocular Lenses Inserted in Cataract Surgery

Purpose This study was conducted to compare post-operative astigmatic outcomes of two groups, with-the-rule (WTR) and against-the-rule (ATR) astigmatism patients, according to the haptic axis of intraocular lenses (IOLs) inserted in cataract surgery. Methods Seventy-two eyes with WTR astigmatism and 79 eyes with ATR astigmatism had cataract surgery through a clear corneal temporal incision. These two groups of eyes were then each divided into 2 groups based on whether the haptic axis of the inserted IOL was at 180° or 90°. For ATR patients, the outcomes were analyzed according to the three types of IOLs. Results There was no difference in corneal astigmatism, but WTR patients with a 180° haptic axis of the inserted IOL and ATR patients with a 90° hepatic axis of the inserted IOL had a significant decrease in postoperative refractive astigmatism (p < 0.05). The changes in ATR astigmatism according to the IOL type were more effective in single-piece acrylic IOLs than in the three-piece polymethylmethacrylate haptic IOL group. Conclusions Insertion of the IOL at the 180° haptic axis in WTR patients and at 90° in ATR patients during cataract surgery may have an effect in reducing pre-existing astigmatism. This observed effect was not consistent among the different types of IOLs.