Department of Ophthalmology, Ehime University Graduate School of Medicine, Shitsukawa, Toon, Ehime, 791-0295, Japan.
Clinical Laboratory Division, Ehime University Hospital, Shitsukawa, Toon, Ehime, 791-0295, Japan.
Sci Rep. 2024 Apr 5;14(1):8024. doi: 10.1038/s41598-024-58659-7.
Diabetes mellitus is recognized as a major predisposing factor for Moraxella keratitis. However, how diabetes mellitus contributes to Moraxella keratitis remains unclear. In this study, we examined Moraxella keratitis; based on the findings, we investigated the impact of advanced glycation end products (AGEs) deposition in the cornea of individuals with diabetic mellitus on the adhesion of Moraxella isolates to the cornea. A retrospective analysis of 27 culture-proven cases of Moraxella keratitis at Ehime University Hospital (March 2006 to February 2022) was performed. Moraxella isolates were identified using matrix-assisted laser desorption ionization time-of-flight mass spectrometry. Among the patients, 30.4% had diabetes mellitus and 22.2% had the predominant ocular condition of using steroid eye drops. The species identified were Moraxella nonliquefaciens in 59.3% and Moraxella lacunata in 40.7% of patients. To investigate the underlying mechanisms, we assessed the effects of M. nonliquefaciens adherence to simian virus 40-immortalized human corneal epithelial cells (HCECs) with or without AGEs. The results demonstrated the number of M. nonliquefaciens adhering to HCECs was significantly increased by adding AGEs compared with that in controls (p < 0.01). Furthermore, in the corneas of streptozotocin-induced diabetic C57BL/6 mice treated with or without pyridoxamine, an AGE inhibitor, the number of M. nonliquefaciens adhering to the corneas of diabetic mice was significantly reduced by pyridoxamine treatment (p < 0.05). In conclusion, the development of Moraxella keratitis may be significantly influenced by the deposition of AGEs on the corneal epithelium of patients with diabetes mellitus.
糖尿病被认为是导致莫拉氏菌角膜炎的主要诱发因素。然而，糖尿病如何导致莫拉氏菌角膜炎尚不清楚。在这项研究中，我们检查了莫拉氏菌角膜炎；基于这些发现，我们研究了糖尿病患者角膜中晚期糖基化终产物（AGEs）沉积对莫拉氏菌分离株与角膜黏附的影响。对爱媛大学医院（2006 年 3 月至 2022 年 2 月）确诊的 27 例培养阳性莫拉氏菌角膜炎病例进行回顾性分析。使用基质辅助激光解吸电离飞行时间质谱法鉴定莫拉氏菌分离株。在这些患者中，30.4%有糖尿病，22.2%主要眼部状况是使用皮质类固醇眼药水。鉴定出的物种是 59.3%的莫拉氏非液化菌和 40.7%的莫拉氏陷窝菌。为了研究潜在机制，我们评估了 M. nonliquefaciens 与或不与 AGEs 结合到猴病毒 40 永生化人角膜上皮细胞（HCEC）的附着效应。结果表明，与对照组相比，添加 AGEs 后，M. nonliquefaciens 附着到 HCEC 的数量显著增加（p<0.01）。此外，在链脲佐菌素诱导的糖尿病 C57BL/6 小鼠的角膜中，用或不用 AGE 抑制剂吡哆胺治疗后，糖尿病小鼠角膜中附着的 M. nonliquefaciens 数量显著减少（p<0.05）。总之，AGEs 在糖尿病患者角膜上皮的沉积可能显著影响莫拉氏菌角膜炎的发展。
