Abstract
Purpose :
A neuroprotective effect of glial cell line-derived neurotrophic factor (GDNF) was demonstrated in animal models of glaucoma. It is important to study GDNF content in the human eye and lacrimal fluid for clarification of GDNF role in glaucoma pathogenesis. However, in practice this analysis is impossible except of during surgical interventions. An age-related cataract has relatively weak influence on concentrations of neurotrophic factors. The aim of the study was to measure GDNF levels in the aqueous humor, lacrimal fluid, and blood serum in patients with age-related cataract.
Methods :
Forty-seven patients (47 eyes) operated for age-related cataract were examined. Exclusion criteria were any serious ophthalmic or somatic pathology, high refractive errors. Mean age of patients was 74.0±7.4 years (range 57-88 years); there were 17 men and 30 women. Collection of stimulated lacrimal fluid was performed by a pipette on the day preceding surgery; the aqueous humor of the anterior chamber and the blood were sampled during the phacoemulsification of a cataract. The concentration of GDNF was measured in the studied biological media by an enzyme immunoassay using RayBio® Human GDNF ELISA Kit (RayBiotech, USA) on a ChemWell 2910 automatic analyzer (Awareness Technology Inc., USA).
Results :
Median (interquartile range) of GDNF concentration was 83 (59–119) pg/mL in aqueous humor, 196 (174–239) pg/mL in serum, and 314 (244–422) pg/mL in lacrimal fluid. In 3 cases, GDNF content in aqueous humor was less than minimum detectable value (4 pg/mL). The concentrations of GDNF in the studied biological media did not show significant correlation with each other. Only correlation of GDNF levels in lacrimal fluid and serum showed Pearson’s correlation coefficient r over 0.2 (r=0.27, P=0.07).
Conclusions :
In patients with age-related cataract, the median GDNF concentration in aqueous humor is more than 2 times lower than in blood serum and more than 3.5 times lower than in lacrimal fluid. The concentrations of GDNF in the studied biological media are not correlated with each other. These data could be used for comparison with those of patients with combined glaucoma and age-related cataract.
This is a 2021 ARVO Annual Meeting abstract.