Osteoarthritis Research Unit, University of Montreal Hospital Research Center (CRCHUM), Montreal, QC, Canada.
LBEES, Genetics and Immune Cell Therapy Unit, Faculty of Sciences, University Mohamed Premier, Oujda, Morocco.
Inflamm Res. 2023 Dec;72(12):2145-2153. doi: 10.1007/s00011-023-01805-0. Epub 2023 Oct 24.
15-Lipoxygenase-1 (15-LOX-1) catalyzes the biosynthesis of many anti-inflammatory and immunomodulatory lipid mediators and was reported to have protective properties in several inflammatory conditions, including osteoarthritis (OA). This study was designed to evaluate the expression of 15-LOX-1 in cartilage from normal donors and patients with OA, and to determine whether it is regulated by DNA methylation.
Cartilage samples were obtained at autopsy from normal knee joints and from OA-affected joints at the time of total knee joint replacement surgery. The expression of 15-LOX-1 was evaluated using real-time polymerase chain reaction (PCR). The role of DNA methylation in 15-LOX-1 expression was assessed using the DNA methyltransferase inhibitor 5-Aza-2'-desoxycytidine (5-Aza-dC). The effect of CpG methylation on 15-LOX-1 promoter activity was evaluated using a CpG-free luciferase vector. The DNA methylation status of the 15-LOX-1 promoter was determined by pyrosequencing.
Expression of 15-LOX-1 was upregulated in OA compared to normal cartilage. Treatment with 5-Aza-dC increased 15-LOX-1 mRNA levels in chondrocytes, and in vitro methylation decreased 15-LOX-1 promoter activity. There was no difference in the methylation status of the 15-LOX-1 gene promoter between normal and OA cartilage.
The expression level of 15-LOX-1 was elevated in OA cartilage, which may be part of a repair process. The upregulation of 15-LOX-1 in OA cartilage was not associated with the methylation status of its promoter, suggesting that other mechanisms are involved in its upregulation.
15-脂氧合酶-1（15-LOX-1）催化许多抗炎和免疫调节脂质介质的生物合成，并被报道在几种炎症性疾病中具有保护作用，包括骨关节炎（OA）。本研究旨在评估 15-LOX-1 在正常供体和 OA 患者软骨中的表达，并确定其是否受 DNA 甲基化调控。
尸检时从正常膝关节和全膝关节置换术时受 OA 影响的关节中获取软骨样本。使用实时聚合酶链反应（PCR）评估 15-LOX-1 的表达。使用 DNA 甲基转移酶抑制剂 5-Aza-2'-去脱氧胞苷（5-Aza-dC）评估 DNA 甲基化在 15-LOX-1 表达中的作用。使用无 CpG 荧光素酶载体评估 CpG 甲基化对 15-LOX-1 启动子活性的影响。通过焦磷酸测序确定 15-LOX-1 启动子的 DNA 甲基化状态。
与正常软骨相比，OA 中的 15-LOX-1 表达上调。5-Aza-dC 处理增加软骨细胞中的 15-LOX-1 mRNA 水平，体外甲基化降低 15-LOX-1 启动子活性。正常和 OA 软骨中 15-LOX-1 基因启动子的甲基化状态没有差异。
OA 软骨中 15-LOX-1 的表达水平升高，这可能是修复过程的一部分。OA 软骨中 15-LOX-1 的上调与启动子的甲基化状态无关，表明其上调涉及其他机制。
