Dysregulation of Glypicans and Notum in Osteoarthritis: Plasma Levels, Bone Marrow Mesenchymal Stromal Cells and Osteoblasts.

Study of alterations in Osteoarthritis (OA) of Glypicans 1 to 6 (GPCs) and Notum in plasma, bone marrow mesenchymal stromal cells (BM-MSCs) and osteoblasts. Plasma levels of GPCs and Notum were measured of 25 patients and 24 healthy subjects. In addition, BM-MSCs from eight OA patients and eight healthy donors were cultured during 21 days with culture me-dium and osteogenic medium. Protein and gene expression levels of GPCs and Notum were de-termined by ELISA and qPCR at 0, 7 ,14 and 21 days. GPC5 and Notum have been found de-creased in OA patients’ plasma. OA BM-MSCs showed downexpression of GPC6 and upregula-tion of Notum. A decrease in GPC5 and Notum proteins and an increase in GPC3 were found. During osteogenic differentiation, elevated GPC2, 4, 5, 6 and Notum mRNA levels and decreased GPC3 were observed in OA. Furthermore, the protein levels of GPC2, GPC5 and Notum de-creased and GPC3 increased. Glypicans and Notum are altered in BM-MSCs and during osteo-genic differentiation from patients with OA. Furthermore, GPC5 and Notum can be proposed as new biomarkers of the pathology. The alterations found indicate that Notum could be a prom-ising therapeutic strategy for Osteoarthritis.