ABSTRACT
The review of our retinal studies performed on Japanese quail Coturnix japonica in 2010–2017 years is presented. There are data on: (a) age-related morphological changes in retinal pigment epithelium (RPE) and choroid; (b) the dependence of the age-related changes in RPE and choroid on the spectral composition of everyday illumination; (c) evaluation of retinal structures age resistance to the photodamaged effect of blue light; and (d) study of RPE cellular activity photomodulation by low-dose light emitting diodes radiation. Methods of light-optical and electron microscopy, biochemical studies with the use of vital fluorescent dyes were applied. It is shown that pronounced age-related disorders are manifested in deformations of the RPE cell nuclei and the structures of the hemato-retinal barrier. The presumed causes of senile retinal disorders are genetic aging, as well as the accumulation of lipofuscin granules in RPE. There were adaptive 180responses to compensate for age-related disorders at the level of RPE mitochondria and choriocapillaris. The study on the dependence of the age-related changes on the spectral composition of daily illumination was performed with the use of blue (440–470 nm) and yellow (500–650 nm) light in the physiological range. In the data we obtained, blue everyday illumination compared to yellow light had a notable activation effect in an increase in the number of RPE mitochondria and choriocapillaris at a young age. The overall picture of RPE and choroid cells aging under blue and yellow light was approximately the same. In studies on blue light damage (440–460 nm, 4 J/cm2), it was found that blue irradiation induced RPE cells of young animals’ changes similar to the usual age-related state of RPE (deformation of the cell nuclei and basal processes and adaptive changes in the mitochondria shapes). Studies on the photomodulatory action of weak blue light (0.001–1 J/cm2) on the cellular activity were carried out on a suspension of the RPE cells. We revealed that such illumination led to a marked activation of cellular and mitochondrial activity (estimated by an increase in the fluorescence of resazurin and tetramethylrhodamine ethyl ester), as well as to the increase in the number of RPE mitochondria (detected by electron microscopy). All the obtained results correlate with the data known for human.
