Objective To review the research progress on lactylation modification in the pathogenesis of osteoarthritis (OA). Methods Relevant studies published in recent years on lactate metabolism and lactylation modification in OA were retrieved and analyzed, summarizing the molecular mechanisms of lactylation and its regulatory roles in different cells and pathological processes. Results Lactate, as the major metabolic product of glycolysis, not only participates in energy metabolism but also plays a crucial role in OA progression through lactylation modification. Lactate-driven histone and non-histone lactylation regulate gene transcription and cellular functions, contributing to chondrocyte metabolic reprogramming, extracellular matrix (ECM) synthesis and degradation, cell proliferation and apoptosis, as well as ferroptosis. In fibroblast-like synoviocytes, lactylation modification promotes cellular senescence and the release of inflammatory factors; in immune cells, lactylation regulates inflammatory responses by influencing macrophage polarization and intercellular communication. Overall, lactylation modification exhibits a dual effect in OA: it aggravates ECM degradation and inflammation on the one hand, but under specific microenvironments, it also promotes repair and regeneration. However, the site-specificity, cell-type heterogeneity, and cross-talk of lactylation with other epigenetic modifications remain to be further clarified. Conclusion Lactylation modification provides a novel perspective for understanding the metabolic and epigenetic mechanisms of OA and may serve as a potential biomarker and therapeutic target. Future studies combining multi-omics approaches to map the global lactylation landscape, together with small-molecule inhibitors, epigenetic editing tools, and regenerative medicine strategies, may enable precise regulation of lactylation, offering new strategies to delay or even reverse OA progression.
