Role of calcifying nanoparticles in the calcification process of mesenchymal stem cells in vitro

The role of calcifying nanoparticles (CNPs) in the calcification process of the outer cyst wall of hepatic cystic echinococcosis is still unknown. CNPs were isolated from the tissues of patients with cystic hepatic echinococcosis. Western blotting, alkaline phosphatase (ALP) staining, and Alizarin-Red S staining were performed to detect cellular calcium ion deposition induced by CNPs. CCK-8 and flow cytometry assays were conducted to determine the effect of CNPs on the apoptosis of mesenchymal stem cells (MSCs). Western blot experiments were performed to examine the expression level of apoptosis-related factors and TGF-β1/Smad signaling pathway activation. CNPs treatment induced the MSCs to differentiate into osteoblast-like cells. Calcification-related proteins including OPN, BMP-2, and RUNX2 were upregulated under CNPs treatment. Similarly, the CNPs exposure also increased cellular calcium ion deposition in MSCs. Furthermore, the expression of Bax and Caspase-8 was elevated by CNPs in MSCs. Treatment of CNPs promoted MSC apoptosis and inhibited the growth of MSCs. The TGF-β1/Smad signaling pathway was also activated after CNPs treatment. This study demonstrated that CNPs may play a critical role in initiating the calcification of the outer cyst wall of cystic hepatic echinococcosis and promoting the decay of the echinococcosis, providing a new strategy for the treatment of hepatic echinococcosis.