Researchers fed mice a high-fat diet to model obesity-related osteoarthritis, then dissected three parallel mechanisms driving joint damage: (1) DNA damage in chondrocytes activates a p53-FOXO3 signaling loop that accelerates cartilage breakdown; (2) subchondral bone osteoclasts undergo ferroptosis — an iron-dependent cell death — driven by inflammatory signals from senescent adipocytes; and (3) bone marrow mesenchymal stem cells shift toward fat cell production, whose senescence-associated secretory phenotype (SASP) then fuels osteoclast ferroptosis. Delivering FOXO3-expressing lentivirus directly into mouse joints reduced cartilage degeneration and abnormal bone remodeling. Human joint samples from arthroplasty patients validated the mouse findings, suggesting these pathways operate in clinical obesity-related OA.
