Determination Of Osmotic Proteins In Lens Capsules Of Patients With Diabetes Mellitus.
Published 2025 - 43rd Congress of the ESCRS
Reference: FP10.09 | Type: Free paper | DOI: 10.82333/pnc1-pw82
Authors: Yujie Deng* 1 , Zheng Wang 1
1Refractive surgery center,Guangzhou Aier Eye Hospital,Guangzhou,China
Purpose
The polyol pathway is a metabolic pathway in which glucose is reduced to sorbitol within the lens as a result of high intracellular glucose levels. It has been postulated that the accumulation of sorbitol within the cells leads to changes in the avascular microcirculation system of the lens and osmotic damage. Kir4.1, TRPV4 and LRRC8A are osmotic proteins that have been studied as important mediators of the retinal microenvironment and aqueous humor secretion; but their expression and role in the physiology of the lens have not been ellucidated.The purpose of this study is to determine by immunofluorescence the expression and distribution pattern of Kir4.1, TRPV4 and LRRC8A in cataracts of patients with and without diabetes mellitus (DM).
Setting
The study was conducted in the Research Unit of the "“Asociación Para Evitar la Ceguera en México” (APEC), recruiting lens capsular samples during cataract surgery from patients at the same hospital throughout the period August 2022 – May 2024. The study adhered to the statutes of the Declaration of Helsinki and was approved by the research and ethics committees of APEC. The number of participants in the project was developed as appropriate, since it is an exploratory study.
Methods
We recruited 50 patients in the “Asociación Para Evitar la Ceguera en México” (25 diabetic and 25 non-diabetic), all candidate for cataract phacoemulsification. We obtained the capsules for each group transoperatively by a continuous circular capsulorhexis. The capsules were fixed, permeabilized and incubated with a primary antibody and a secondary antibody coupled with a fluorophore for immunofluorescence studyig. We performed a descriptive statistic, obtaining the mean and standard deviation, in addition to a t-student test for the statistical significance of the fluorescence intensity through the study of 1000 cells per field in three independent experiments for each osmotic protein using the software Cytation 5 microscope analysis.
Results
We observed that Kir4.1, TRPV4 and LRRC8A were expressed in the lens capsules of both populations. The capsules of the non-diabetic group showed a heterogeneous fluorescent expression for Kir4.1 and TRPV4 throughout the tissue, with some isolated foci of intense fluorescence; while the diabetic group presented a similar inespecific pattern for Kir4.1 and TRPV4. LRRC8A showed a more homogeneous fluorescent expression in the control group with evident foci of higher fluorescence in comparison to the more attenuated expression in the diabetic group. However, the quantitative analysis identified a lower expression intensity of Kir4.1, TRPV4 and LRRC8A in the capsules of the diabetic group and statistically significant for TRPV4 and LRRC8A.
Conclusions
This is the first clinical research work that studies the expression of the osmotic proteins Kir4.1, TRPV4 and LRRC8A in lens capsules. The lower fluorescent cellular expression of Kir4.1, TRPV4 and LRRC8A within the capsules of the diabetic group suggests that persistent high intracellular levels of glucose can lead to alterations in the avascular microcirculation system of the lens, compromising the ion and water homeostasis and precipitating the cataract formation in this vulnerable population. The identification of these ionic markers and the understanding of their role in the formation of cataract in diabetic patients may be relevant for the development of future therapeutical targets.