BackgroundAniridia is a severe autosomal dominant panocular disorder associated with pathogenic sequence variants of the PAX6 gene or 11p13 chromosomal aberrations encompassing the coding and/or regulatory regions of the PAX6 gene in a heterozygous state. Patients with aniridia display several ocular anomalies including foveal hypoplasia, cataract, keratopathy, and glaucoma, which can vary in severity and combination.MethodsA cohort of 155 patients from 125 unrelated families with identified point PAX6 pathogenic variants (118 patients) or large chromosomal 11p13 deletions (37 patients) was analyzed. Genetic causes were divided into 6 types. The occurrence of 6 aniridic eye anomalies was analyzed. Fisher’s exact test was applied for 2×2 contingency tables assigning numbers of patients with/without each sign and each type of the PAX6 variants or 11p13 deletions with Benjamini–Hochberg correction. The age of patients with different types of mutation did not differ.ResultsPatients with 3′-cis-regulatory region deletions had a milder aniridia phenotype without keratopathy, nystagmus, or foveal hypoplasia. The phenotypes of the patients with other rearrangements involving 11p13 do not significantly differ from those associated with point pathogenic variants in the PAX6 gene. Missense mutations and genetic variants disrupting splicing are associated with a severe aniridia phenotype and resemble loss-of-function mutations. It is particularly important that in all examined patients, PAX6 mutations were found to be associated with multiple eye malformations. The age of patients with keratopathy, cataract, and glaucoma was significantly higher than the age of patients without these signs.ConclusionWe got clear statistically significant genotype-phenotype correlations in congenital aniridia and evident that aniridia severity indeed had worsened with age.

Purpose: to assess the level of catecholamines norepinephrine and dopamine in rat retina with experimental retinopathy of prematurity (EROP) at a time corresponding to the peak of neovascularization.Material and methods. The study was performed on 41 infant Wistar rats (82 eyes). The rats were divided into 2 groups: the experimental group (with EROP, n = 21) and the control group (n = 20). In order to reproduce the EROP, the newborn rats were placed for 14 days in the incubator together with their mother. Every 12 hours, the oxygen concentration in the incubator ranged from 60 to 15 %. The control group consisted of pups who were held in conditions with a normal oxygen content (21 %) from the moment of birth. The pups were withdrawn from the experiment on the 10th, 14th, 23rd and 28th day, whereupon they were subjected to binocular enucleation followed by histological examination, in addition, the content of noradrenaline and one of the metabolites of dopamine (L-DOPA) was determined in retinal samples of the eyeballs obtained on the 23rd day by highly effective liquid chromatography technique with electrochemical detection.Results. Histological examination showed that in our EROP model the neovascularization peak occurs on the 23rd day of the experiment. At this time rat pups with EROP showed a significantly lower retinal L-DOPA level as compared to the control values (13.99 ng/g and 30.5 ng/g, respectively), and the norepinephrine level significantly exceeded such values (63.7 ng/g and 7.69 ng/g, respectively).Conclusion. A relative deficiency of dopamine and a relative excess of norepinephrine of the rat pups with EROP is noted at the time of the highest vascular activity of the retina. The obtained data confirm anti-angiogenic properties of dopamine and pro-angiogenic properties of noradrenaline in the second phase of EROP development.

No abstract

In premature babies, plastic changes develop in the neural retina, which, depending on the severity of retinopathy of prematurity (ROP), are a manifestation of adaptive or non-adaptive plasticity. In various experimental studies on animal ROP models, the conditioning effects of intermittent white light stimulation and various mechanisms of the positive effect of red and ultraviolet radiation on the plasticity of the retina have been demonstrated, which allows phototherapy to be considered as a promising modifying treatment for ROP supplementing the main therapy. Taking into account that light-dependent processes are involved in the pathogenesis of ROP, we also hypothesize that fractal phototherapy with complex-structured optical stimuli, as a method of activating adaptive neuroplasticity, can be most effective in the complex of methods for preventing and treating ROP.

Exogenous melatonin, due to its strong antiangiogenic and antioxidant activity, helps stabilize the blood-retinal barrier in OIR.