Pancreatic Cholesterol Esterase, ES-10, and Fatty Acid Ethyl Ester Synthase III Gene Expression Are Increased in the Pancreas and Liver but Not in the Brain or Heart with Long-term Ethanol Feeding in Rats

Introduction: Chronic alcohol consumption predisposes susceptible individuals to both acute and chronic pancreatitis.

Aims: Our hypothesis was that alcohol increases the risk of pancreatitis by disrupting defense mechanisms and/or enhancing injury-associated pathways through altered gene expression. Hence, we studied the expression of pancreatic genes in rats chronically exposed to ethanol.

Methodology: Male Wistar rats were pair-fed liquid diets without and with ethanol for 4 weeks. Total RNA was extracted from rat pancreas and other organs. The mRNA expression patterns among pancreatic samples from ethanol-fed rats and controls were compared with use of mRNA differential display. The differentially expressed cDNA tags were isolated, cloned, and sequenced.

Results: One cDNA tag that was overexpressed in the pancreas showed 99% sequence homology to a rat pancreatic cholesterol esterase mRNA (CEL; Enzyme Commission number [EC] 3.1.1.13). The differential expression was confirmed by realtime PCR. Gene expression was also increased in the liver but not in the heart or brain of the alcohol-fed rats. Because CEL has fatty acid ethyl ester (FAEE)-generating activity and FAEEs play a major role in acute alcoholic pancreatitis, we determined the expression of other genes encoding for FAEE-generating enzymes and showed similar organ-specific expression patterns.

Conclusion: Our results demonstrate that chronic ethanol consumption induced expression of FAEE-related genes in the pancreas and liver. This upregulation may be a central mechanism leading to acinar cell injury.