Maki Miyauchi

Violet Light Exposure Can Be a Preventive Strategy Against Myopia Progression

Prevalence of myopia is increasing worldwide. Outdoor activity is one of the most important environmental factors for myopia control. Here we show that violet light (VL, 360–400 nm wavelength) suppresses myopia progression. First, we confirmed that VL suppressed the axial length (AL) elongation in the chick myopia model. Expression microarray analyses revealed that myopia suppressive gene EGR1 was upregulated by VL exposure. VL exposure induced significantly higher upregulation of EGR1 in chick chorioretinal tissues than blue light under the same conditions. Next, we conducted clinical research retrospectively to compare the AL elongation among myopic children who wore eyeglasses (VL blocked) and two types of contact lenses (partially VL blocked and VL transmitting). The data showed the VL transmitting contact lenses suppressed myopia progression most. These results suggest that VL is one of the important outdoor environmental factors for myopia control. Since VL is apt to be excluded from our modern society due to the excessive UV protection, VL exposure can be a preventive strategy against myopia progression.

A highly efficient murine model of experimental myopia

Despite the global pandemic of myopia, the precise molecular mechanism of the onset of myopia remains largely unknown. This is partially because of the lack of efficient murine myopic models that allow genetic manipulation at low cost. Here we report a highly practical and reproducible lens-induced myopia model by specially designed frames and lenses for mice. A lens power dependent myopic induction in mice was shown until minus 30 diopter lenses. The phenotype was significantly stronger than form-deprivation myopia. We presented the protocol for precise evaluations of the state of myopia, including refraction, corneal curvature and axial length using up-to-date devices. We also found that myopic mouse eyes showed decreased visual acuity on optokinetic response examination. Finally, we confirmed the anti-myopic effect of 1% atropine using this model, which showed its potential in drug screening. The strong phenotype, stable evaluation and the potential for gene manipulation utilizing the presented method in mice will accelerate the translational research of myopia.