Ethanol-induced augmentation of annexin IV expression in rat C6 glioma and human A549 adenocarcinoma cells.

BACKGROUND: We previously reported that the amount of annexin IV significantly increased in the postmortem brains of alcoholics compared with controls. To investigate further whether ethanol directly affects cellular expression of annexins in a cell, we used cell lines and compared the amounts of annexins between ethanol-exposed and control cells.
METHODS: Two kinds of cells (rat glioma C6 cells and human adenocarcinoma A549 cells) were used in the present study. Western blot analysis was performed to quantify expressed amounts of annexins using anti-annexin I, IV, and V antibodies. The mitochondrial enzyme (dehydrogenase) and caspase 3 activities were measured to assess cell damage (apoptosis) by ethanol.
RESULTS: Expressive augmentation of annexin IV was shown in both C6 and A549 cells after a 5-hr exposure to 200 mM of ethanol, whereas amounts of annexins I and V were not changed. Both the mitochondrial dehydrogenase and caspase 3 activities were altered under the same conditions in C6 cells, indicating the induction of cell damage (apoptosis), whereas both of these enzyme activities were unchanged in A549 cells under the same conditions.
CONCLUSIONS: The amount of annexin IV seemed to increase before the induction of cell damage by ethanol. Annexin IV might be one of the specific markers for the effect of ethanol.