Purpurin Alleviates Meniscal Senescence and Osteoarthritis by Blocking the Non‐Metabolic Function of Hexokinase 2

ABSTRACT Meniscal degeneration, characterised by extracellular matrix (ECM) loss and cellular senescence, plays a critical role in osteoarthritis (OA) progression, yet the underlying mechanisms remain unclear. Although hexokinase 2 (HK2) is recognised as a key glycolytic enzyme, its potential non‐metabolic functions in the meniscus remain unexplored. In this study, HK2 expression was evaluated in human OA and normal meniscus tissues, and its non‐metabolic effects were investigated in primary meniscal cells using overexpression, knockdown, and site‐directed mutagenesis; protein interactions were analysed by immunoprecipitation‐mass spectrometry (IP‐MS) and co‐immunoprecipitation (Co‐IP). HK2 was significantly upregulated in OA meniscal tissues, and overexpression of catalytically inactive HK2 promoted meniscal ECM degradation and cellular senescence in an MYH10‐dependent manner. Mechanistically, HK2 enhanced the MYH10–PRKN interaction, inducing K48‐linked ubiquitination of MYH10 at lysine 410 and its subsequent proteasomal degradation, thereby reducing COL1A1 mRNA stability. Purpurin, identified through virtual screening, disrupted the HK2–MYH10 interaction in vitro, prevented MYH10 degradation, and attenuated cellular senescence. In the destabilisation of the medial meniscus (DMM) mouse model, intra‐articular injection of adeno‐associated virus expressing catalytically inactive HK2 exacerbated OA progression, whereas purpurin treatment alleviated meniscal degeneration, ECM loss, and OA‐associated pain. Collectively, HK2 promotes meniscal senescence and OA progression through a non‐metabolic, MYH10‐dependent mechanism, and purpurin represents a promising lead compound for disease‐modifying osteoarthritis drug (DMOAD) development.