Human fgf21

The human THP-1 cells were obtained from the Type Culture Collection of the Chinese Academy of Sciences (Shanghai, China). THP-1 cells were cultured in Roswell Park Memorial Institute medium 1640 (RPMI 1640, Hyclone) containing 10 % fetal bovine serum and 2 mM L-glutamine. The cells were differentiated into macrophages by adding 100 ng/mL phorbol 12-myristate-13-acetate for 24 h, and the medium was then replaced with that containing ox-LDL (50 mg/mL) and human FGF21 (Peprotech, 20 nmol/L) for 24 h to obtain fully differentiated foam cells before use in experiments. And human FGF21 (Peprotech, 20 nmol/L) was added to cotreat the THP1 macrophage derived foam cell.

Progenitor‐enriched cell populations were isolated from muscle samples as described previously (Vaughan & Lamia, 2019 ), and cultured on Matrigel (BD Biosciences, Franklin Lake, NJ, USA) at 39°C in Dulbecco's modified Eagle's medium (DMEM) high glucose with 1% P/S, supplemented with 20% fetal bovine serum (FBS) (Life Technologies, Carlsbad, CA, USA) and 5 ng mL^–1 basic FGF (PeproTech, London, UK). Cells were trypsinized and passaged every 2−3 days. MPCs were differentiated using a protocol adapted from Hausman & Poulos (2005 (link)). In short, MPCs were plated on rh‐Laminin 521 (Life Technologies)‐coated wells (1000 cells mm^–2) and, when they reached 70% confluency, media was changed to DMEM high glucose with antibiotics supplemented with 10% FBS and 80 nm dexamethasone (Sigma‐Aldrich). Forty‐eight hours later or when cells reached full confluence (day 0), media was changed to DMEM high glucose with antibiotics supplemented with 2% FBS, 1% of insulin‐transferrin‐selenium (Life Technologies) and, in some experiments, human FGF21 (1−100 ng mL^–1; #100‐42; PeproTech), and maintained for up to 7 days. All experiments with cells were performed using triplicate wells.