Periodontal Ligament-associated Protein-1/Asporin in Periodontal Health: A Crucial Regulator of Oral and Systemic Function

The periodontal ligament (PDL) is a specialized, vascularized fibrous tissue that anchors teeth to the alveolar bone, supports mechanical actions like chewing, and aids in tissue maintenance, wound repair, and regeneration. It is mainly composed of fibroblasts that form a network of key fibers linking the tooth root’s cementum to the alveolar bone. Recently, PDL-associated protein-1 (PLAP-1), also known as asporin, a member of the small leucine-rich proteoglycan family, has been identified as a crucial protein within the PDL. Asporin plays a key role in maintaining tissue balance by regulating bone morphogenetic protein (BMP) signaling, specifically inhibiting BMP-2 to prevent abnormal bone growth, such as ankylosis. Its unique N-terminal sequence of 16 aspartic acid residues is vital for maintaining periodontal tissue health. Although asporin’s role in conditions such as periodontitis, osteoarthritis, cancer, and heart failure is being studied, its exact function in periodontal health is still under investigation. This review delves into the structure, function, and regulatory roles of PLAP-1/asporin, highlighting its potential protective role in periodontal health and its broader implications for systemic diseases. A deeper understanding of asporin’s multifunctional roles may lead to new therapeutic strategies for both periodontal and systemic conditions.