Akito Shimouchi

Neuroprotective effect of water-dispersible hesperetin in retinal ischemia reperfusion injury

PurposeTo determine whether water-dispersible hesperetin (WD-Hpt) can prevent degeneration of ganglion cell neurons in the ischemic retina.MethodsIschemia reperfusion (I/R) injury was induced by increasing the intraocular pressure of mice to 110xa0mmHg for 40xa0min. Mice received daily intraperitoneal injections with either normal saline (NS, 0.3xa0ml/day) or WD-Hpt (0.3xa0ml, 200xa0mg/kg/day). Reactive oxygen species (ROS) was assessed by dihydroethidium and nitrotyrosine formation. Inflammation was estimated by microglial morphology in the retina. Lipopolysaccharide (LPS)-stimulated BV-2 cells were used to explore the anti-inflammatory effect of WD-Hpt on activated microglia by quantifying the expression of IL-1β using real-time quantitative reverse transcription-polymerase chain reaction. Ganglion cell loss was assessed by immunohistochemistry of NeuN. Glial activation was quantified with glial fibrillary acidic protein (GFAP) immunoreactivity. Apoptosis was evaluated with a terminal deoxynucleotidyl transferase (TUNEL) assay and immunohistochemistry of cleaved caspase-3. Phosphorylation of extracellular signal-regulated kinase (p-ERK) was surveyed by western blotting.ResultsWD-Hpt decreased I/R-induced ROS formation. WD-Hpt alleviated microglial activation induced by I/R and reduced mRNA levels of IL-1β in LPS-stimulated BV-2. I/R resulted in a 37xa0% reduction in the number of ganglion cells in the NS-treated mice, whereas the reduction was only 5xa0% in the WD-Hpt-treated mice. In addition, WD-Hpt mitigated the immunoreactivity of GFAP, increased expression of cleaved caspase-3, increased number of TUNEL positive cells and p-ERK after I/R.ConclusionsWD-Hpt protected ganglion cells from I/R injury by inhibiting oxidative stress and modulating cell death signaling. Moreover, WD-Hpt had an anti-inflammatory effect through the suppression of activated microglia.

Vitreomacular interface in patients with familial exudative vitreoretinopathy

Familial exudative vitreoretinopathy (FEVR) is a rare hereditary vitreoretinal disease that occurs in young patients and results in an avascular peripheral retina, retinal neovascularization, and tractinal retinal detachment. Patients occasionally have concurrent macular diseases. However, the vitreomacular relationship in FEVR remains unclear. We report two cases, a 22-year-old woman (case 1) and a 14-year-old boy (case 2) with FEVR who have the characteristic findings of the disease in the vitreomacular interface and the macular morphology, observed using spectral-domain optical coherence tomography (SD-OCT). In case 1, the best-corrected visual acuity (BCVA) was 20/20 bilaterally. SD-OCT showed a perifoveal posterior vitreous detachment (PVD) with vitreofoveal adhesion in the left eye. In case 2, SD-OCT showed a perifoveal PVD in the right eye (BCVA, 20/30) with numerous small deposits that appeared as rod-shaped attachments perpendicular to the parafoveal face without intraretinal and subretinal materials beneath the posterior hyaloid face that corresponded to white material on the fundus examination. Fluorescein angiography showed a circumferential peripheral avascular area and peripheral neovascularization in both cases. These SD-OCT findings suggested that a perifoveal PVD and small deposits, which appeared as rod-shaped attachments perpendicular to the parafoveal face in patients with FEVR, may carry the risk of macular disease and decreased visual acuity.

Serum prorenin levels are not associated with ocular diseases in non-diabetic subjects.

Introduction: To determine if the serum prorenin level is useful for detecting ocular disease in a non-diabetic population. Materials and methods: We enrolled non-diabetic men (n = 402) and women (n = 349) in our study. We used the antibody-activating direct enzyme kinetic assay of human prorenin to determine serum prorenin levels. We performed multiple regression analysis to determine the factors that affect serum prorenin levels, such as: age, body mass index (BMI), systolic blood pressure (SBP), diastolic blood pressure (DBP), total cholesterol, fasting blood sugar, and HbA1c or estimated glomerular filtration rate. Our study subjects were divided into groups by their ophthalmologic diagnosis. One-way analysis of variance (ANOVA) was performed to detect a significant difference in the serum prorenin levels among the groups. Results: There were no significant differences in serum prorenin levels among the ocular diseases and disorders. The DBP was negatively correlated with serum prorenin levels in men (r = − 0.1992; p = 0.021) and in women (r = − 0.2067; p = 0.031). Conclusion: Considering the current results and those of previous studies together, we found that the prorenin value is useful solely for predicting development of diabetic retinopathy in adults.