The retina is an ideal target for gene therapy because of its easy accessibility and limited immunological response. We previously reported that intravitreally injected adeno-associated virus (AAV) vector transduced the inner retina with high efficiency in a rodent model. In large animals, however, the efficiency of retinal transduction was low, because the vitreous and internal limiting membrane (ILM) acted as barriers to transduction. To overcome these barriers in cynomolgus monkeys, we performed vitrectomy (VIT) and ILM peeling before AAV vector injection. Following intravitreal injection of 50 μL triple-mutated self-complementary AAV serotype 2 vector encoding EGFP, transduction efficiency was analyzed. Little expression of GFP was detected in the control and VIT groups, but in the VIT+ILM group, strong GFP expression was detected within the peeled ILM area. To detect potential adverse effects, we monitored the retinas using color fundus photography, optical coherence tomography, and electroretinography. No serious side effects associated with the pretreatment were observed. These results indicate that surgical ILM peeling before AAV vector administration would be safe and useful for efficient transduction of the nonhuman primate retina and provide therapeutic benefits for the treatment of retinal diseases.

In phacoemulsification, ultrasound induces hydroxyl radical (·OH) formation, damaging corneal endothelium. Whether H2 can prevent such oxidative damage in phacoemulsification was examined by in vitro and in vivo studies. H2 was dissolved in a commercial irrigating solution. The effects of H2 against ·OH generation were first confirmed in vitro by electron-spin resonance (ESR) and hydroxyphenyl fluorescein (HPF). ESR showed a significantly decreased signal magnitude, and fluorescence intensity by oxidized HPF was significantly less in the H2-dissolved solution. The effects of H2 in phacoemulsification were evaluated in rabbits, comparing H2-dissolved and control solutions. Five hours after the procedure, the whole cornea was excised and subjected to image analysis for corneal edema, real-time semiquantitative PCR (qPCR) for heme oxygenase (HO)-1, catalase (CAT), superoxide dismutase 1 (SOD1), and SOD2 mRNA, and immunohistochemistry. Corneal edema was significantly less and the increases in anti-oxidative HO-1, CAT and SOD2 mRNA expressions were significantly suppressed in the H2 group. In addition, corneal endothelial cell expressions of two oxidative stress markers, 4-HNE and 8-OHdG, were significantly lower in the H2 group. In conclusion, H2 dissolved in the ocular irrigating solution protected corneal endothelial cells from phacoemulsification-induced oxidative stress and damage.

PURPOSE: Hydrogen (H 2 ) has been reported to scavenge free radicals, particularly the hydroxyl radical ($OH). Ultrasound oscillation in an aqueous solution produces $OH. Our recent study demonstrated that H 2 dissolved in an irrigation solution prevented corneal endothelial damage during phacoemulsification in an animal model. We examined the effects of H 2 during clinical phacoemulsification.DESIGN: A single-center, prospective, randomized, double-masked clinical trial.METHODS: Thirty-two patients who had cataracts of similar nucleus hardness in both eyes (age: 75.4±7.68 years; 17 males, 15 females) were recruited. Phacoemulsification was performed using a solution of dissolved H 2 in one eye, and a conventional solution in the contralateral eye. Endothelial cell density (ECD) at the center of the cornea was measured using noncontact specular microscopy preoperatively and at 1 day, 1 week, and 3 weeks postoperatively.RESULTS: Reduction rates of ECD (mean ± standard deviation) were 16.0%±15.7% at 1 day, 15.4%±16.1% at 1 week, and 18.4%±14.9% at 3 weeks in the control group, compared to 6.5%±8.7% at 1 day (P [ .003), 9.3%±11.0% at 1 week (P [ .039), and 8.5%±10.5% at 3 weeks (P [ .004) in the H 2 groups. These rates were significantly smaller in the H 2 group at all time points.CONCLUSIONS: H 2 dissolved in irrigation solution reduced corneal endothelial damage during phacoemulsification. This suggests that a considerable part of the corneal endothelial damage during phacoemulsification is caused by oxidative stress, and that H 2 is useful in clinical phacoemulsification.

Purpose. The aim of this study was to measure the serum levels of brain-derived neurotrophic factor (BDNF) in primary open angle glaucoma (POAG) and normal tension glaucoma (NTG) patients in Japan. Methods. This was a prospective, observational study that examined serum BDNF levels in 78 patients who underwent cataract surgery or trabeculectomy (27 glaucoma patients and 51 non-glaucoma cataract patients as controls). The patients' age was 68.8 ± 11.1 years (mean ± standard deviation; range 35-86 years). The number of patients with POAG and NTG was 16 and 11, respectively. The diagnosis of POAG was done by intraocular pressure measurement, gonioscopy, optic nerve head change, and the presence of a visual field defect. Results. The serum BDNF concentration was significantly lower in the glaucoma group, including both POAG and NTG, than in the control group (7.2 ± 3.6 ng/mL vs. 12.2 ± 9.3 ng/mL, p=0.004). The serum BDNF concentration was lower in the early phase than in the moderate phases of glaucoma. There was no correlation between the serum BDNF concentration and age. When the NTG and POAG patient groups were compared, the serum BDNF concentration was lower in NTG patients than in POAG patients. No significant correlations were found between glaucoma parameters, including optical coherence tomography and visual field defects, and the serum BDNF concentration. Conclusion. This is the first study to have investigated serum BDNF concentrations in glaucoma patients in Japan. Further investigations are needed to evaluate the role of BDNF as a potential biomarker of glaucoma.

Purpose: Because dry eye greatly reduces quality of life, this study aimed to examine rebamipide instillation in patients with dry eye and assess the improvement of signs and symptoms as evaluated with the Ocular Surface Disease Index, which is the most popular index and is highly reliable. Methods:From June 2013 through January 2014, we examined 50 eyes of 25 patients with dry eye (6 men and 19 woman) at our institution. Dry eye was diagnosed on the basis of the presence of symptoms, tear dynamics, and ocular surface abnormalities according to the Japanese criteria for dry eye. Before being enrolled, all patients underwent ocular surface health assessment, including history interviews, and completed the Ocular Surface Disease Index questionnaire. Patients received 2% rebamipide ophthalmic solution 4 times daily for 4 weeks. Signs and symptoms were analyzed before and 4 weeks after rebamipide administration. Tear dynamics, tear break-up time, and ocular surface abnormalities were measured and compared between before and 4 weeks after rebamipide administration. Results:Of the 25 patients, 9 had definite dry eye and 16 had probable dry eye. Tear break-up time and the fluorescein staining score significantly improved after 4 weeks. However, no significant change was observed for the Schirmer test I and the lissamine green staining score. Conclusions:The administration of 2% rebamipide 4 times daily for 4 weeks improves the signs and symptoms of dry eye and improves patients' quality of life. (J Nippon Med Sch 2015; 82: 229 236)