Evidence of Mitophagy in Lens Capsule Epithelial Cells of Patients with Pseudoexfoliation Syndrome.

Abstract

Prcis: Alterations in the PINK-mediated mitophagy pathway play an important role in PEX disease.

Purpose: Pseudoexfoliation Syndrome (PEX) is a condition in which aberrant fibrillary protein builds up in various components of the eye and other extraocular tissues. In this study, we aim to investigate the functionality of intracellular auto-degradative machinery -especially mitophagy- and related genes and proteins in PEX.

Methods: Anterior lens capsules were obtained from cataracts patients with and without PEX to constitute the PEX group and age-matched controls during microincision cataracts surgery. PINK1-mediated mitophagy markers were evaluated on the transcriptional and translational level via RT-qPCR and immunohistochemistry analysis, respectively.

Results: The lens epithelial cells of PEX patients were characterized by significantly higher PINK1 gene expression compared to that of the controls (P<0.05). In terms of intensity of staining of expressed proteins, PINK1 (P<0.05), Parkin (P<0.01) and LC3B (P<0.01) were all statistically higher in PEX, compared to the controls.

Conclusion: Altered auto-degradative response -specifically mitophagy- is a component of increased oxidative stress in PEX patients. The role of this mechanism in emerging complications warrants further research.