Glucagon like peptide glp 1

IPCs were induced using a modified three-step, 10-day version of the insulin-transferrin-selenium (ITS) induction method first established in tonsil MSCs [60 (link),66 (link)]. In step 1, hUC-MSCs and hAD-MSCs in high-glucose alpha-minimal essential medium (α-MEM; HyClone Laboratories, Logan, UT, USA) were seeded in an uncoated 90 mm × 15 mm dish (Nunc, Naperville, IL, USA) with bovine serum albumin (BSA; Sigma-Aldrich, St. Louis, MO, USA) without 1% fatty acids (Sigma-Aldrich, St. Louis, MO, USA), and ITS media supplement was added at 37 °C in a 5% CO₂ incubator for 2-day. In step 2, 0.3 mM taurine (Sigma-Aldrich, St. Louis, MO, USA) and 10 mM nicotinamide (Sigma-Aldrich, St. Louis, MO, USA) were added to the differentiation medium detailed in step 1, and cells were incubated for 4 d. In step 3 (trans-differentiation), 100 nM glucagon-like peptide (GLP-1, Sigma-Aldrich, St. Louis, MO, USA) and 10 nM exendin-4 (Sigma-Aldrich, St. Louis, MO, USA) were added to the differentiation medium defined in step 2, and cells were incubated for 4 -day. Culture was performed for 10-day.

IPC differentiation was performed by using 10 days 3-step differentiation protocol as performed by Sawangmake et al. (2014) (13). Briefly, 1 × 10⁶ of hDPSCs were seeded in 60 mm non-treated culture dish (Eppendorf, Hamburg, Germany) as a single cell suspension. The cells were maintained in serum-free medium (SFM)-A for 3 days, SFM-B for 2 days and SFM-C for 5 days and the medium were changed every 48 h. The medium used in this experiment were SFM-DMEM (Thermo Fisher Scientific Corporation, USA) with different supplementation. The supplementation of each medium were respectively as follows; SFM-A: 1% BSA (Cohn fraction V, fatty acid free; Sigma, Missouri, USA), 1X insulin-transferrin-selenium (ITS) (Invitrogen, USA), 4 nM activin A (Sigma, Sigma, Missouri, USA), 1 nM sodium butyrate (Sigma, Missouri, USA), and 50 μM beta-mercaptoethanol (Sigma, Missouri, USA); SFM-B: 1% BSA, 1X ITS, and 0.3 mM taurine (Sigma, Missouri, USA); and SFM C: 1.5% BSA, 1X ITS, 3 mM taurine, 100 nM glucagon-like peptide (GLP)-1 (Sigma, Missouri, USA), 1 mM nicotinamide (Sigma, Missouri, USA), and 1x non-essential amino acids (NEAAs) (Sigma, Missouri, USA).