2.9 | Cell proliferation assay
A tetrazolium-based non-radioactive proliferation assay kit (Quick Cell Proliferation Assay Kit II, BioVision, Cat# K301-500) was used to determine the cell number according to the manufacturer’s protocol (Tong et al., 2016). SKI SMCs were seeded in 96-well plate at a density of 5 × 103 cells per well in DMEM supplemented with 0.2% FBS overnight. Cell proliferation was stimulated by medium supplemented with 10% FBS, and 0.2% FBS medium was used as a control. PDTC (10 μM) or pioglitazone (10 μM) was added to the culture media. DMSO served as a solvent control. Culture medium with high or low serum was changed daily. The cell number in each well was determined 72 hr later.