Influence of bile acid on proliferation and ERK expression in human normal esophageal epithelial cells

    JIANG Zhiª²Ru, GONG Jun, ZHANG Zhenª²Ni, ZENG Wenª²Bin

    Department of Gastroenterology, Department of Anesthesiology, Second Affiliated Hospital, Xi¬ðan Jiaotong University, Xi¬ðan 710004, China, Department of Anesthesiology, Cancer Hospital of Shannxi Province, Xi¬ðan 710061, China

    ¡¾Abstract¡¿ AIM: To observe the influence of bile acid on cell proliferation and the expression of extracellular signalª²regulated protein kinase (ERK) in human normal esophageal epithelial cells in vitro. METHODS: Human normal esophageal epithelial cells cultured in vitro were exposed to media containing 6 different kinds of bile acids (250 ¦Ìmol/L) respectively for 3ª²60 min, in comparison with the control group (in normal media without bile acid). Cell proliferation was assessed using MTT and flow cytometry. The expression of phosphorylated ERK1/2 protein was determined by the immunoblotting technique. RESULTS: Bile acidª²exposed (3ª²12 min) esophageal epithelial cells exhibited a significant increase in proliferation, especially in S phase of the cell cycle, and the level of phosphorylated ERK1/2 protein. While the bile acidª²exposed period exceeded 20 min, esophageal epithelial cells exhibited a degression in proliferation and proportion on S phase of the cell cycle. CONCLUSION: The brief exposure in bile acid increases the proliferation in human normal esophageal epithelial cells by activating the ERK pathway. ......