PDGF signaling in cartilage regeneration: molecular mechanisms and cellular effects

Cartilage damage has long been a challenge in regenerative medicine research, due to the avascular nature of cartilage tissue and its intrinsically limited reparative capacity. In recent years, more and more studies have found that the regulation of signaling factors at the temporal, spatial, and dose levels is one of the key factors restricting the effective regeneration of cartilage. As a classic growth factor, platelet-derived growth factor (PDGF) plays an important regulatory role in cell recruitment, proliferation, and tissue repair, and has gradually become the focus of cartilage regeneration research. Evidence has shown that PDGF exhibits significant context-dependent regulatory characteristics in different microenvironments. This review systematically reviews the structural characteristics and signal transduction pathways of different PDGF isoforms and their receptors (PDGFR-α and PDGFR-β), focusing on their biological roles at the cellular level, including the regulation of mesenchymal stem cell migration and expansion, the impact on chondrocyte survival and metabolic activity, and their bidirectional regulatory effects in the synovium-cartilage axis and osteoarthritis-related microenvironment.