Effect of Cyclosporin A (CsA) on Periodontal Ligament Stem Cells (PDLSCs)

Objectives: This study investigates the effect of cyclosporin A (CsA) on the osteogenic differentiation, osteoclastogenic-supporting ability, and angiogenic potential of human periodontal ligament stem cells (hPDLSCs).
Methods: hPDLSCs were isolated from human periodontal ligament cells that were harvested from extracted teeth. Cell viability was assessed through 3-[45-dimethylthiazol-2-yl]-2,5-diphenyl tetrazolium bromide assay. Osteogenic differentiation of hPDLSCs was evaluated by ALP and ARS staining. Real-time PCR analysis was used to quantify the related gene expression. Following treatment with conditioned medium of CsA-exposed or non-exposed hPDLSCs, TRAP staining of bone marrow-derived macrophages (BMMs) and tube formation assay of human umbilical vein endothelial cells (HUVECs) were done. Signaling pathways of angiogenic supporting activity were identified by western blotting.
Results: CsA diminished viability of hPDLSCs, whereas it enhanced osteogenic differentiation of hPDLSCs according to ALP, ARS staining and PCR analysis results of osteogenic markers (BMP2, ALP, OCN, and OPN). The expression of osteoclastogenic markers (M-CSF and RANKL) in hPDLSCs and the differentiation of BMMs treated with conditioned medium from CsA-exposed hPDLSCs were not affected by CsA. CsA diminished the expression of angiogenic marker (VEGF, bFGF, and ANGPT1) genes and factors (ERK, p38, and c-fos) that are involved in the pro-angiogenic supporting pathway of hPDLSCs. The conditioned medium decreased tube formation ability of HUVECs.
Conclusions: CsA enhanced the osteogenic differentiation and diminished angiogenic by blocking the ERK, p38/c-fos pathway in hPDLSCs. Its role in osteogenic differentiation and angiogenesis can be utilized for periodontal regeneration, if its application is testified and verified in the future animal studies.