Department of the Joint and Bone Surgery, Yantaishan Hospital, Yantai, Shandong, China.
Department of Pathophysiology, Binzhou Medical University, Binzhou, Shandong, China.
Autoimmunity. 2022 Dec;55(8):559-566. doi: 10.1080/08916934.2022.2114466. Epub 2022 Aug 31.
Studies have reported that megakaryocytic leukemia 1 (MKL1) is closely related to the pathological process of a variety of inflammatory diseases, but its role in osteoarthritis (OA) needs to be clarified. This study aimed to investigate the regulatory role of MKL1 in oxidative stress-induced chondrocyte apoptosis and cartilage matrix degeneration. The expressions of target mRNAs and proteins were measured by using reverse transcription-quantitative polymerase chain reaction and western blotting. ELISA assay was used to measure the levels of IL-6, IL-8, and TNF-α in chondrocytes. And commercial kits based on different spectrophotometry or colorimetry methods were performed to validate oxidative stress. CCK-8 and apoptosis kits were used to determine cell viability and apoptosis. Rat OA model was established by anterior cruciate ligament transection (ACLT), and the expression of MKL1 was interfered by injecting sh-MKL1 lentiviral vector into caudal vein. The results showed that the expression of MKL1was induced by HO in chondrocytes. Knockdown of MKL1 alleviated HO-induced inflammation and cell apoptosis, reduced HO-induced oxidative stress, and improved cartilage matrix degeneration of chondrocytes. Besides, inhibition of MKL1 regulated the activation of TWIST1-mediated PI3K/AKT signaling. Further studies have found that TWIST1-mediated PI3K/AKT signaling was involved in the regulation mechanism of MKL1 on chondrocyte apoptosis and cartilage matrix degeneration. Next, intervention with MKL1 inhibited the progression of OA in rats. These results demonstrated that MKL1 regulate the apoptosis and cartilage matrix degeneration of chondrocytes via TWIST1-mediated PI3K/AKT signaling.
研究报道巨核细胞白血病 1 (MKL1) 与多种炎症性疾病的病理过程密切相关，但它在骨关节炎 (OA) 中的作用尚需阐明。本研究旨在探讨 MKL1 在氧化应激诱导的软骨细胞凋亡和软骨基质降解中的调控作用。采用逆转录定量聚合酶链反应和 Western blot 检测靶 mRNA 和蛋白的表达。ELISA 法检测软骨细胞中 IL-6、IL-8 和 TNF-α的水平。并采用基于不同分光光度法或比色法的商业试剂盒验证氧化应激。CCK-8 和凋亡试剂盒用于检测细胞活力和凋亡。通过前交叉韧带切断术 (ACLT) 建立大鼠 OA 模型，并通过尾静脉注射 sh-MKL1 慢病毒载体干扰 MKL1 的表达。结果表明，HO 诱导软骨细胞中 MKL1 的表达。敲低 MKL1 减轻了 HO 诱导的炎症和细胞凋亡，减少了 HO 诱导的氧化应激，改善了软骨细胞的软骨基质降解。此外，抑制 MKL1 调节了 TWIST1 介导的 PI3K/AKT 信号的激活。进一步的研究发现，TWIST1 介导的 PI3K/AKT 信号参与了 MKL1 调控软骨细胞凋亡和软骨基质降解的机制。接下来，干预 MKL1 抑制了大鼠 OA 的进展。这些结果表明，MKL1 通过 TWIST1 介导的 PI3K/AKT 信号调节软骨细胞的凋亡和软骨基质降解。
