Gastrointestinal cholecystokinin signaling pathway drugs modulate osteogenic/cementogenic differentiation of human periodontal ligament stem cells.

Objectives: Understanding the complexities of periodontal regeneration, particularly the unpredictable osteogenic/cementogenic differentiation of low-potential PDLSCs (LOP-PDLSCs), remains challenging. Identifying new therapeutic targets is crucial for enhancing regeneration. This study investigates the modulation of the Cholecystokinin (CCK) pathway, a key signaling cascade with roles in the gastrointestinal system, as a potential osteogenic/cementogenic pathway in PDLSCs.

Methods: Gastrointestinal CCK-related drugs, Lorglumide and Sincalide, were tested for their effects on mineralization in PDLSCs. Lorglumide blocked the CCK pathway in high-potential PDLSCs (HOP-PDLSCs), while Sincalide enhanced mineralization in low-potential PDLSCs (LOP-PDLSCs). Cellular viability was tested under different drug concentrations, followed by a mineralization assay (AR-S) using non-toxic doses. RT-qPCR for osteogenic-related genes (IGF1, OCN, RUNX2) and CCK pathway-related genes (CCK, CCKAR, CCKBR, COX2, FOS, JNK3, RGS2) assessed gene modulation. Alkaline phosphatase (ALP) activity, Ca²⁺ quantification, and IP3 receptor phosphorylation were also evaluated.

Results: Lorglumide reduced mineralization, ALP activity, and RUNX2, OCN, and IGF1 transcripts in HOP-PDLSCs (p < 0.05). It decreased CCK and CCKAR expression, modulated COX2, FOS, JNK3, and RGS2 genes, reduced IP3 receptor phosphorylation, and lowered calcium levels (p < 0.05). Conversely, Sincalide enhanced mineralization in LOP-PDLSCs, increasing ALP activity and OCN and IGF1 expression (p < 0.05). It upregulated COX2, FOS, JNK3, and RGS2 genes, phosphorylated IP3 receptors in LOP1, and increased calcium levels in all LOP-PDLSCs (p < 0.05).

Conclusions: Sincalide and Lorglumide modulate PDLSCs' osteogenesis/cementogenesis, revealing the complex interplay of gastrointestinal drugs in periodontal tissue regeneration and offering insights for innovative therapies.

Clinical Significance: This study demonstrates the potential of gastrointestinal drugs targeting the CCK signaling pathway as innovative modulators for periodontal regeneration. By regulating osteogenic/cementogenic differentiation in hPDLSCs, these findings may pave the way for the development of novel biomaterials and therapies, promising improved outcomes in periodontal tissue regeneration for clinical applications.