Insulin enhances epidermal growth factor- and transforming growth factor- αstimulated growth in primary cultures of Guinea pig gastric mucous epithelial cells

Rutten MJ, Harmon P, Campbell DR. Insulin enhances epidermal growth factor-and transforming growth factor-αstimulated growth in primary cultures of guinea pig gastric mucous epithelial cells. Scand J Gastroenterol 1991, 26, 965-973 The effect of insulin on epidermal growth factor (EGF)- and transforming growth factor-α (TGFαinduced cell proliferation was examined in primary cultures of gastric surface mucous epithelial cells by using changes in cell counts and DNA as indices of cell growth. With 1.0 % fetal bovine serum and Dulbecco's modified Eagle medium (low-serum DMEM) there was no effect of bovine insulin (0.1-10.0 μg/ml) on cell growth. Higher doses of insulin (20.0 μg/ml) in low-serum DMEM were able to stimulate growth of these cells compared with controls. In low-serum DMEM with no insulin the lowest effective dose of EGF or TGFα for stimulating cell growth was 10 nM and 5 nM, respectively. In low-serum DMEM containing 2.5 μg/ml insulin there was a dose-dependent increase in cell growth with EGF and TFGα at concentrations of 0.5-10.0 nM. The addition of insulin alone at 2.5 μg/ml, EGF alone at 2 nM, or TGFα alone at 2 nM in serum-free DMEM media had no effect on gastric surface mucous cell DNA. In serum-free DMEM media with 2.5 μg/ml insulin, the addition of 2 nM EGF or 2 nM TGFα caused an increase in both cell counts and DNA of 1.80- and 3.50-fold, respectively. The present study demonstrates that insulin, at concentrations that are not mitogenic, will enhance the proliferative effects of EGF and TGFα on the growth of primary cultures of guinea pig gastric surface mucous epithelial cells.