Department of Clinical Chemistry and Biochemistry, Medical University of Lodz, 90-419 Lodz, Poland.
Department of Pathology and Laboratory Medicine, Medical University of South Carolina, Charleston, SC 29425, USA.
Int J Mol Sci. 2024 Jan 5;25(2):728. doi: 10.3390/ijms25020728.
The term glaucoma encompasses various neurodegenerative eye disorders, among which the most common is primary open-angle glaucoma (POAG). Recently, the essential role of human retinal astrocytes (HRA) in glaucoma progression has been placed in the spotlight. It has been found that placing the endoplasmic reticulum (ER) under stress and activating PERK leads to apoptosis of HRA cells, which inhibits their neuroprotective effect in the course of glaucoma. Therefore, the aim of the present study was to evaluate the effectiveness of the small-molecule PERK inhibitor LDN-0060609 in countering ER stress conditions induced in HRA cells in vitro. The activity of LDN-0060609 was studied in terms of protein and mRNA expression, cytotoxicity, genotoxicity, caspase-3 level and cell cycle progression. LDN-0060609 at 25 μM proved to be a potent inhibitor of the major PERK substrate, p-eIF2α (49% inhibition). The compound markedly decreased the expression of pro-apoptotic ER stress-related genes (, , and ). Treatment with LDN-0060609 significantly increased cell viability, decreased genotoxicity and caspase-3 levels, and restored cell cycle distribution in HRA cells with activated ER stress conditions. These findings indicate that the small-molecule PERK inhibitor LDN-0060609 can potentially be developed into a novel anti-glaucoma agent.
青光眼包括各种神经退行性眼病，其中最常见的是原发性开角型青光眼（POAG）。最近，人视网膜星形胶质细胞（HRA）在青光眼进展中的重要作用成为研究焦点。研究发现，内质网（ER）受到压力并激活 PERK 会导致 HRA 细胞凋亡，从而抑制其在青光眼过程中的神经保护作用。因此，本研究旨在评估小分子 PERK 抑制剂 LDN-0060609 对抗体外培养的 HRA 细胞 ER 应激的效果。研究了 LDN-0060609 在蛋白质和 mRNA 表达、细胞毒性、遗传毒性、caspase-3 水平和细胞周期进展方面的活性。25μM 的 LDN-0060609 被证明是主要 PERK 底物 p-eIF2α 的有效抑制剂（抑制率为 49%）。该化合物显著降低了促凋亡 ER 应激相关基因（、、和）的表达。用 LDN-0060609 处理可显著提高细胞活力，降低遗传毒性和 caspase-3 水平，并恢复激活 ER 应激条件下 HRA 细胞的细胞周期分布。这些发现表明，小分子 PERK 抑制剂 LDN-0060609 有可能开发成为一种新型抗青光眼药物。
