Triptolide Attenuates Traumatic Heterotopic Ossification via Modulation of Inflammatory and Differentiation Pathways: Implications for Biochemical Toxicology

Traumatic heterotopic ossification (THO) is a pathological process characterized by ectopic bone formation in soft tissues following trauma or surgical interventions, leading to pain, swelling, and restricted mobility. Current therapeutic strategies remain limited, with surgical excision often associated with recurrence and complications. Triptolide (TP), a diterpenoid triepoxide derived from Tripterygium wilfordii, has potent anti-inflammatory and immunomodulatory effects, making it a promising candidate for THO treatment. This study explored the molecular mechanisms underlying the therapeutic potential of TP in THO, focusing on its effects on inflammatory and differentiation pathways. Using in vitro models with mouse tendon stem/progenitor cells (TSPCs) and RAW264.7 macrophages, as well as an in vivo mouse model of THO, we demonstrated that TP significantly inhibits key signalling pathways involved in THO pathogenesis, including the NF-κB, TGF-β-Smad, and Notch pathways. TP reduces the levels of Pro-inflammatory cytokines (IL-1β and TNF-α) and suppresses the osteogenic and chondrogenic differentiation of mesenchymal stem cells, which are critical processes in THO development. Moreover, compared with the commonly used anti-inflammatory drug indomethacin, TP markedly reduces ectopic bone formation in vivo, exhibiting superior efficacy. These findings highlight the potential of TP as a novel therapeutic agent for THO, providing new insights into its biochemical and molecular effects relevant to toxicology and inflammation regulation.