circSPG21 protects against intervertebral disc disease by targeting miR-1197/ATP1B3.

The abnormal expression of circular RNAs (circRNAs) is associated with numerous human diseases. This study investigated the mechanism by which circRNA acts as competitive endogenous RNA in the regulation of degenerative intervertebral disc disease (IVDD). Decreased expression of circSPG21 was detected in degenerated nucleus pulposus cells (NPCs), the function of circSPG21 in NPCs was explored and verified, and the downstream target of circSPG21 was investigated. The interaction between circSPG21 and miR-1197 and its target gene (ATP1B3) was studied by online database prediction and molecular biological verification. Finally, the circSPG21/miR-1197/ATP1B3 axis was verified in the mouse tail-looping model. The expression of circSPG21 in the nucleus pulposus in IVDD was directly related to an imbalance of anabolic and catabolic factors, which affected cell senescence. circSPG21 was found to play a role in human NPCs by acting as a sponge of miR-1197 and thereby affecting ATP1B3. The regulation of circSPG21 provides a potentially effective therapeutic strategy for IVDD. A type of non-coding circular RNA implicated in maintaining the cartilaginous discs found between adjacent vertebrae of the spine offers a promising new therapeutic target for treating chronic lower back pain. A team from China led by Bin Fang of China Medical University, Shaoxing, and Jianjun Ma of Zhejiang University School of Medicine, Hangzhou, found that people with degenerative intervertebral disc disease (IVDD) express low levels of a circular RNA known as circSPG21 in the cells that populate the area between spinal discs. The researchers showed how this RNA interacts with a regulatory microRNA to affect the function of a protein involved in warding off cell death. Injections of circSPG21 alleviated the symptoms of IVDD in a mouse model, highlighting its therapeutic potential in humans.