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Aims To determine if 'Defocus Incorporated Soft Contact' (DISC) lens wear slows childhood myopia progression. Methods A 2-year double-blind randomised controlled trial was carried out in 221 children aged 8-13 years, with myopia between -1.00 and -5.00 Dioptres (D) and astigmatism ≤1.00 D. Subjects were randomly assigned to the DISC (n=111) or single vision (SV; n=110) contact lens group. DISC lenses incorporated concentric rings, which provided an addition of +2.50 D, alternating with the normal distance correction. Refractive error (cycloplegic autorefraction) and axial length were measured at 6-month intervals. Differences between groups were analysed using unpaired t test. Results In total, 128 children completed the study, n=65 in the DISC group and n=63 in the SV group. Myopia progressed 25% more slowly for children in the DISC group compared with those in the control group (0.30 D/year; 95% CI -0.71 to -0.47 vs 0.4 D/year; 95% CI -0.93 to -0.65, p=0.031). Likewise, there was less axial elongation for children in the DISC versus SV groups (0.13 mm/year; 95% CI 0.20 to 0.31 vs 0.18 mm/year; 95% CI 0.30 to 0.43, p=0.009). Treatment effect correlated positively with DISC lens wearing time (r=0.342; p=0.005). Indeed, myopia in children who wore the DISC lenses for five or more hours/day progressed 46% (mean difference=-0.382 D, p=0.001; 95% CI -0.59 to -0.17) less than those in the SV group. Conclusions The daily wearing of DISC lens significantly slowed myopia progression and axial elongation in Hong Kong schoolchildren. The findings demonstrated that simultaneous clear vision with constant myopic defocus can retard myopia progression. [ABSTRACT FROM AUTHOR]

Retinal aging has been recognized as a significant risk factor for various retinal disorders, including diabetic retinopathy, age-related macular degeneration, and glaucoma, following a growing understanding of the molecular underpinnings of their development. This comprehensive review explores the mechanisms of retinal aging and investigates potential neuroprotective approaches, focusing on the activation of transcription factor EB. Recent meta-analyses have demonstrated promising outcomes of transcription factor EB-targeted strategies, such as exercise, calorie restriction, rapamycin, and metformin, in patients and animal models of these common retinal diseases. The review critically assesses the role of transcription factor EB in retinal biology during aging, its neuroprotective effects, and its therapeutic potential for retinal disorders. The impact of transcription factor EB on retinal aging is cell-specific, influencing metabolic reprogramming and energy homeostasis in retinal neurons through the regulation of mitochondrial quality control and nutrient-sensing pathways. In vascular endothelial cells, transcription factor EB controls important processes, including endothelial cell proliferation, endothelial tube formation, and nitric oxide levels, thereby influencing the inner blood-retinal barrier, angiogenesis, and retinal microvasculature. Additionally, transcription factor EB affects vascular smooth muscle cells, inhibiting vascular calcification and atherogenesis. In retinal pigment epithelial cells, transcription factor EB modulates functions such as autophagy, lysosomal dynamics, and clearance of the aging pigment lipofuscin, thereby promoting photoreceptor survival and regulating vascular endothelial growth factor A expression involved in neovascularization. These cell-specific functions of transcription factor EB significantly impact retinal aging mechanisms encompassing proteostasis, neuronal synapse plasticity, energy metabolism, microvasculature, and inflammation, ultimately offering protection against retinal aging and diseases. The review emphasizes transcription factor EB as a potential therapeutic target for retinal diseases. Therefore, it is imperative to obtain well-controlled direct experimental evidence to confirm the efficacy of transcription factor EB modulation in retinal diseases while minimizing its risk of adverse effects., (Copyright © 2025 Copyright: © 2025 Neural Regeneration Research.)

Aim: To investigate the retinal toxicity and pharmacokinetics of simvastatin intravitreally injected into mice., Methods: Forty-eight 6-8-week-old C57BL/6J mice were used in this study. Simvastatin was intravitreally injected into the right eye of each mouse; the left eye was injected with vehicle and was used as a control. Bilateral dark-adapted electroretinography (ERG) was performed 1 and 7d following injection. Histology was examined using a combination of light, fluorescence and electron microscopy. High-performance liquid chromatography (HPLC) was used to determine the decay in the retinal simvastatin concentration., Results: ERG revealed no significant changes in the simvastatin-injected eyes compared to control. Histologic studies showed normal retinal morphology in eyes injected with simvastatin up to a final vitreal concentration of 200 µmol/L. No significant changes in the number of photoreceptors, bipolar cells or ganglion cells were found. The retinal simvastatin concentration decayed exponentially, with a half-life of 1.92-2.41h., Conclusion: Intravitreal injection of up to 200 µmol/L simvastatin produced no signs of adverse effects in the mouse retina. Simvastatin reaches the retina shortly after intravitreal injectionand has a short half-life.

Purpose: The immediate early gene Egr-1 is thought to form part of the pathway that mediates abnormal ocular growth. This study investigated whether the mRNA expression levels of Egr-1 in a mammalian retina are modulated differentially, depending on the direction of ocular growth., Methods: To induce accelerated growth and myopia, guinea pigs wore a -5 diopter (D) lens over one eye from 4 to 11 days of age. To induce inhibited growth, the lens was removed after 7 days of -5 D lens wear, and the eye allowed to recover from myopia for 3 days. Ocular parameters and Egr-1 mRNA levels were subsequently assessed, and compared to untreated fellow eyes and eyes from untreated littermates. Possible circadian changes in Egr-1 mRNA levels were also determined in 18 additional animals by taking measures every 4 hours during a 24-hour cycle., Results: Ocular compensation to a -5 D lens occurred after 7 days (Δ -4.8 D, Δ +147 μm growth, N = 20). In 5 highly myopic eyes (Δ -7.4 D), Egr-1 mRNA levels in the retina were significantly downregulated relative to contralateral control (51%) and age-matched untreated (47%) eyes. Three days after the -5 D lens was removed, eyes had recovered from the myopia (Δ -0.5 D, relative change of +2.9 D, N = 4) and Egr-1 mRNA levels were significantly elevated relative to contralateral (212%) and untreated (234%) eyes, respectively. Normal Egr-1 mRNA expression was higher in the middle of the day than in the middle of the night. Immunolabeling showed strong Egr-1 reactivity in cell bodies in the inner nuclear and ganglion cell layers., Conclusions: Egr-1 mRNA levels in a mammalian retina show a bi-directional persistent response to opposing ocular growth stimuli. This suggests retinal Egr-1 might act as a signal for the direction of ocular growth in different species., (Copyright 2014 The Association for Research in Vision and Ophthalmology, Inc.)