Department of Orthopaedic Surgery, The 12839Jikei University School of Medicine, Tokyo, Japan.
Mol Pain. 2021 Jan-Dec;17:17448069211014059. doi: 10.1177/17448069211014059.
Osteoarthritis of the knee impairs activities of daily living of those affected. Its irreversible degenerative changes to the knee joint induce functional disturbance and unpleasant arthralgia. The pain has inflammatory components and often is manifested with mechanical allodynia and hyperalgesia. Sustained weight bearing and joint movements increase pain sensitivity in knee osteoarthritis. Understanding the mechanisms underlying the mechanical allodynia and hyperalgesia might provide a therapeutical target for pain relief in patients with such symptoms. Piezo channel is a mechanically activated ion channel that may be involved in mechanical transduction in the articular cartilage. Although it has been shown that inflammation potentiates Piezo channel current induced by mechanical stimulation, whether Piezo expression levels are influenced by knee osteoarthritis has remained unknown. We measured Piezo mRNA in knee joints and dorsal root ganglia after establishing a model of knee osteoarthritis in rats using monosodium iodoacetate and found Piezo mRNA level is not upregulated. This finding raises a question as whether and how Piezo channels may be involved in mechanically induced pain in osteoarthritis.
膝骨关节炎会损害患者的日常生活活动能力。其膝关节的不可逆转退行性变化会引起功能障碍和不适的关节痛。这种疼痛具有炎症成分，常常表现为机械性痛觉过敏和痛觉过敏。持续的负重和关节运动增加了膝骨关节炎患者的疼痛敏感性。了解机械性痛觉过敏和痛觉过敏的机制可能为有此类症状的患者提供缓解疼痛的治疗靶点。Piezo 通道是一种机械激活的离子通道，可能参与关节软骨的机械转导。虽然已经表明炎症增强了机械刺激引起的 Piezo 通道电流，但 Piezo 表达水平是否受膝骨关节炎影响尚不清楚。我们在大鼠膝骨关节炎模型中用单钠碘乙酸盐建立模型后，测量了膝关节和背根神经节中的 Piezo mRNA，发现 Piezo mRNA 水平没有上调。这一发现提出了一个问题，即 Piezo 通道是否以及如何参与骨关节炎中的机械性疼痛。
