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

Abstract

Prcis: Alterations in the PTEN-induced kinase 1 (PINK)-mediated mitophagy pathway play an important role in pseudoexfoliation syndrome (PEX) disease.

Purpose: 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.

Materials and methods: Anterior lens capsules were obtained from cataract patients with and without PEX to constitute the PEX group and age-matched controls during microincision cataract surgery. PINK1-mediated mitophagy markers were evaluated on the transcriptional and translational level via reverse transcriptionquantitative polymerase chain reaction and immunohistochemistry analysis, respectively.

Results: The lens epithelial cells of PEX patients were characterized by significantly higher PINK1 gene expression compared with 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 microtubule-associated protein 1A/1B-light chain 3 B ( P <0.01) were all statistically higher in PEX, compared with 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.