Induction of buccal mucosal apoptosis with chronic alcohol ingestion

In this study we investigated buccal mucosal cells apoptosis and the expression of regulatory cytokines, tumor necrosis factor-alpha (TNF-alpha) and interleukin-4(IL-4) with chronic ethanol ingestion. The buccal mucosa of rats maintained for 23 days on alcohol-containing and control liquid diet was assessed for IL-4 and TNF-alpha content, and the extent of epithelial cells apoptosis. While the expression of TNF-alpha in alcohol diet group showed a significant increase (1.9-fold) over that of the controls, less apparent differences between the two groups were observed in the content of IL-4 (141.8 +/- 28.2 vs. 119.8 +/- 7.3 pg/mg protein). The DNA fragmentation assays revealed that alcohol diet group also exhibited a 3.5-fold enhancement in buccal mucosal cells apoptosis. Moreover, the apoptotic index showed positive correlation (r = 0.53) with the extent of induced changes in TNF-alpha. These results demonstrate that ethanol-induced buccal mucosal cells apoptosis is triggered by the enhancement in TNF-alpha expression.