Human visceral preadipocytes

Human visceral preadipocytes, preadipocyte growth supplement and preadipocyte differentiation supplement were purchased from ScienCell Research Laboratories (San Diego, California, USA). Fetal calf serum was purchased from Gibco (Carlsbad, California, USA), and penicillin‐streptomycin‐amphotericin B solution was purchased from Biological Industries (Cromwell, Connecticut, USA). Human visceral preadipocytes were maintained in Dulbecco's modified Eagle's medium/F12 medium containing 5% Fetal calf serum, preadipocyte growth supplement and penicillin‐streptomycin‐amphotericin B solution according to the manufacturer's protocol. Post‐confluent preadipocytes were replaced with medium containing pre‐adipocyte differentiation supplement and then continued onto differentiation for 5 days. The medium was changed every 3 days. VAP‐1 concentrations in cell culture supernatants were measured using the VAP‐1 human enzyme‐linked immunosorbent assay kit according to the manufacturer's protocol (Abcam, Cambridge, UK). Relative VAP‐1 levels were normalized to total cell counts.