Rosuvastatin suppresses TNF-α-induced matrix catabolism, pyroptosis and senescence via the HMGB1/NF-κB signaling pathway in nucleus pulposus cells: Role of rosuvastatin in alleviating intervertebral disc degeneration

Intervertebral disc degeneration is mainly caused by irregular matrix metabolism in nucleus pulposus cells and involves inflammatory factors such as TNF-α. Rosuvastatin, which is widely used in the clinic to reduce cholesterol levels, exerts anti-inflammatory effects, but whether rosuvastatin participates in IDD remains unclear. The current study aims to investigate the regulatory effect of rosuvastatin on IDD and the potential mechanism. In vitro experiments demonstrate that rosuvastatin promotes matrix anabolism and suppresses catabolism in response to TNF-α stimulation. In addition, rosuvastatin inhibits cell pyroptosis and senescence induced by TNF-α. These results demonstrate the therapeutic effect of rosuvastatin on IDD. We further find that HMGB1, a gene closely related to cholesterol metabolism and the inflammatory response, is upregulated in response to TNF-α stimulation. HMGB1 inhibition or knockdown successfully alleviates TNF-α-induced ECM degradation, senescence and pyroptosis. Subsequently, we find that HMGB1 is regulated by rosuvastatin and that its overexpression abrogates the protective effect of rosuvastatin. We then verify that the NF-κB pathway is the underlying pathway regulated by rosuvastatin and HMGB1. In vivo experiments also reveal that rosuvastatin inhibits IDD progression by alleviating pyroptosis and senescence and downregulating HMGB1 and p65. This study might provide new insight into therapeutic strategies for IDD.