Violet light suppresses lens-induced myopia via neuropsin (OPN5) in mice

Abstract

Purpose : Myopia has become a major public health concern, particularly across much of Asia. It has been shown in multiple studies that outdoor activity has a protective effect on myopia. It is also known that short-wavelength visible violet light is the component of sunlight that appears to play an important role in preventing myopia progression in the chick and in humans. The mechanism underlying this effect has not been understood.

Methods : Lens defocus-induced myopia (LIM) in mice was performed by attaching 0 diopter (D) lenses on the left eyes and -30 D lenses on the right eyes with a frame on their skull. Combined with 50 lux of white background fluorescent lamp light from 08:00 to 20:00 every day, 400 μw/cm² (360 nm ~ 400 nm) of violet light was added either 3 hours pre-dawn (05:00~08:00), all daytime exposure (08:00~20:00), continuous violet light, 3 hours of evening (17:00~20:00), or 3 hours of post-dusk (20:00~23:00) for three weeks of the LIM period. The violet light sensitive atypical opsin neuropsin (OPN5) is specifically deleted in the retina by crossing Chx10-Cre⁺ mice with Opn5^flox/flox mice (OPN5 cKO).

Results : 3 hours of evening violet light combined with white light significantly suppressed both the refractive shift (p=0.006) and axial lengthening (p=0.045) compared to white light only in control mice. By contrast, OPN5 cKO mice with violet light showed a refractive shift and an axial length change indistinguishable from the normal white light condition.

Conclusions : These findings identify OPN5 expressing retinal cells as crucial for emmetropization in mice and further suggest a strategy for myopia prevention in humans.

This is a 2021 ARVO Annual Meeting abstract.