ACTIVATION OF APOPTOTIC CASPASE-3 AND NITRIC-OXIDE SYNTHASE-2 IN BUCCAL MUCOSA WITH CHRONIC ALCOHOL INGESTION

Apoptosis, the process of programmed cell death, involves activation o f caspase proteases cascade that remains under the regulatory control of nitric oxide. In this study, we investigated the activity of a key apoptotic protease, caspase-3, and the expression of nitric oxide synt hase-2 (NOS-2) associated with buccal epithelial cells apoptosis induc ed by chronic ethanol diet. The assays revealed that a 7.9-fold enhanc ement in buccal epithelial cells apoptosis, observed in the alcohol di et group, was accompanied by a 37.6-fold increase in caspase-3 activit y and a 10.1-fold increase in NOS-2. Furthermore, the expression of NO S-2 showed a positive correlation (r = 0.92) with the extent of change s induced in caspase-3 activity. These results implicate caspase-3 in the process of alcohol-induced epithelial cells apoptosis, and point t owards participation of NOS-2 in the amplification of the cell death s ignaling cascade.