Effect of pioglitazone on the calcification of rat vascular smooth muscle cells through the downregulation of the Wnt/[beta]-catenin signaling pathway

The aim of the present study was to investigate the effect and possible mechanism of pioglitazone (PIO) on the calcification of rat vascular smooth muscle cells (VSMCs) in vitro. [beta]-glycerophosphate ([beta]-GP; 10 mmol/l) was used to induce calcification of VSMCs treated with a range of concentrations (5, 10, 15 and 20 [micro]mol/l) of PIO for 12 days. Calcium deposits were revealed by Alizarin red staining. Extracellular calcium content was detected using a calcium assay kit. Western blotting was used to measure the expression of [alpha]-smooth muscle actin ([alpha]-SMA), runt-related transcription factor 2 (Runx2), bone morphogenetic protein-2 (BMP2), [beta]-catenin, glycogen synthase kinase-3[beta] (GSK-3[beta]), phosphorylated (p)-GSK-3[beta] and cyclin-D1. A total of 10 mmol/l [beta]-GP, 20 [micro]mol/l PIO and 20 [micro]mol/l peroxisome proliferator-activated receptor [gamma] (PPAR [gamma]) antagonist GW9662, was added to the cell culture media. The changes of the above indexes were observed. The calcium content in the calcification group, treated with high phosphorus, increased significantly compared with the controls (P