The Potential Role of Small-Molecule PERK Inhibitor LDN-0060609 in Primary Open-Angle Glaucoma Treatment

• Published in: International journal of molecular sciences Vol. 22; no. 9; p. 4494
• Main Authors: Rozpędek-Kamińska, Wioletta, Galita, Grzegorz, Siwecka, Natalia, Carroll, Steven L, Diehl, John Alan, Kucharska, Ewa, Pytel, Dariusz, Majsterek, Ireneusz
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI AG 26.04.2021; MDPI
• Subjects: Age; Apoptosis; Apoptosis - drug effects; Caspase-3; Cell cycle; Cell Line; Cell Proliferation - drug effects; Comet assay; Cytology; Cytotoxicity; Deoxyribonucleic acid; Disease; DNA; DNA damage; DNA Damage - drug effects; eIF-2 Kinase - antagonists & inhibitors; eIF-2 Kinase - metabolism; eIF2α; Endoplasmic reticulum; endoplasmic reticulum stress; Endoplasmic Reticulum Stress - drug effects; Enzymes; Eukaryotic Initiation Factor-2 - metabolism; Evaluation; Flow cytometry; Gene expression; Genotoxicity; Glaucoma; Glaucoma, Open-Angle - drug therapy; Glaucoma, Open-Angle - metabolism; Homeostasis; Humans; Kinases; Morphology; Neurodegeneration; Pathogenesis; PERK; Phosphorylation; Protein folding; Protein kinase; Protein Kinase Inhibitors - adverse effects; Protein Kinase Inhibitors - pharmacology; Proteins; Signal transduction; Transcription factors; unfolded protein response; Unfolded Protein Response - drug effects; Western blotting; eIF2α; unfolded protein response; glaucoma; apoptosis; PERK; PERK inhibitor; endoplasmic reticulum stress; glaucoma treatment
• ISSN: 1422-0067; 1661-6596; 1422-0067
• DOI: 10.3390/ijms22094494

Primary open-angle glaucoma (POAG) constitutes the most common type of glaucoma. Emerging evidence suggests that Endoplasmic Reticulum (ER) stress and the protein kinase RNA-like endoplasmic reticulum kinase (PERK)-mediated Unfolded Protein Response (UPR) signaling pathway play a key role in POAG pathogenesis. Thus, the main aim of the study was to evaluate the effectiveness of the PERK inhibitor LDN-0060609 in cellular model of glaucoma using primary human trabecular meshwork (HTM) cells. To evaluate the level of the ER stress marker proteins, Western blotting and TaqMan gene expression assay were used. The cytotoxicity was measured by XTT, LDH assays and Giemsa staining, whereas genotoxicity via comet assay. Changes in cell morphology were assessed by phase-contrast microscopy. Analysis of apoptosis was performed by caspase-3 assay and flow cytometry (FC), whereas cell cycle progression by FC. The results obtained have demonstrated that LDN-0060609 triggered a significant decrease of ER stress marker proteins within HTM cells with induced ER stress conditions. Moreover, LDN-0060609 effectively increased viability, reduced DNA damage, increased proliferation, restored normal morphology, reduced apoptosis and restored normal cell cycle distribution of HTM cells with induced ER stress conditions. Thereby, PERK inhibitors, such as LDN-0060609, may provide an innovative, ground-breaking treatment strategy against POAG.