WS6 and 5-iodotubercidin small molecules and growth factors; TGF, HGF, and EGF synergistically enhance proliferation of β-like human induced pluripotent stem cells (iPSCs).

Objectives: It has been shown that growth factors and small molecules play an essential role in the proliferation of β cells and insulin production. In this study, we investigated the effects of small molecules (WS6 and 5-iodotubercidin) and growth factors (TGFβ, HGF, and EGF) on the proliferation of β-like human ipSCs.

Methods: iPSCs derived β cells were treated with small molecules and growth factors. Cytotoxic activity of small molecules and growth factors was determined using MTT assay. Insulin gene expression and secretion were measured by qPCR and ELISA, respectively. The protein expression of insulin was evaluated by western blot as well.

Results: Simltananeous addition of WS6 and Harmine into the culture media increased insulin gene expression compared to treatment by each molecule alone ( < 0.05). It was found that the simultaneous recruitment of EGH, HGF, and TGF-β increased insulin expression compared to treatment by each molecule alone ( < 0.05). Results showed that EGF, HGF, TGF-β growth factors increased insulin gene expression, eventually leading to insulin secretion from β cells ( < 0.05).

Conclusions: Growth factors and small molecules synergistically enhanced the proliferation of β cells and insulin production.