Targeting the senescence-associated secretory phenotype to modify osteoarthritis in aging

Osteoarthritis (OA) is a common joint condition correlated with aging, characterized by the gradual degradation of cartilage, alterations in the subchondral bone, and ongoing low-level inflammation. There is growing evidence that the senescence-associated secretory phenotype (SASP) of chondrocytes, which includes the continuous release of IL1β, IL6, TNFα, MMP3, and MMP13, offers a crucial function in driving the pathology of OA. In this review, we consolidate the existing knowledge on the molecular processes that lead to chondrocyte aging, such as NFκB/MAPK signaling, oxidative stress, mitochondrial dysfunction, and epigenetic changes. We also critically assess senotherapeutic strategies, including senolytics (dasatinib + quercetin, ABT263), senomorphics (rapamycin, metformin, pterostilbene), anti-oxidant nanomaterials, and therapies based on extracellular vesicles that specifically reduce SASP while maintaining cartilage health. This study looks at SASP biomarkers in different joint tissues. It also examines how nanotechnology and EV strategies can help renew aging chondrocytes. This review examines the impact of cartilage changes on the aging process. It offers guidance on delaying osteoarthritis, identifies early indicators, and proposes innovative treatments to maintain joint health as grow older.