[Deoxycholate induces apoptosis in cultured normal human esophageal mucosal epithelial cells].

Abstract

Objective: To study the effect of deoxycholate in inducing apoptosis of human normal esophageal mucosal epithelial cells in vitro and investigate the molecular mechanism.

Methods: Cultured normal human esophageal mucosal epithelial cells were treated with deoxycholate, and the cell apoptosis were evaluated with TUNEL, DNA ladder, flow cytometry with PI-staining, Annexin V-FITC conjugated with PI staining, and Western blotting.

Results: Flow cytometry, TUNEL and DNA ladder demonstrated that deoxycholate could induce apoptosis in normal human esophageal mucosal epithelial cells in a dose- and time-dependent manner. A percentage of 21.3% of the cell population treated with deoxycholate at 500 micromol/L for 30 min exhibited detectable caspase-3 activity shown by flow cytometry, which was significantly higher than the control level (1.5%, P<0.01). Western blotting suggested that deoxycholate down-regulated Bcl-2 protein expression and up-regulated Bax expression, but Fas was negative in the cells before and after deoxycholate treatment.

Conclusions: Deoxycholate could induce apoptosis in cultured human esophageal mucosal epithelial cells. Aaspase-3 activation, Bcl-2 protein down-regulation and Bax up-regulation are involved in deoxycholate-induced apoptosis, which does not involve Fas-L/Fas.