In Vitro Effects of Ethanol on Human Gastric and Pancreatic Lipolytic Activities/Enzymes

Abstract

Background: Ethanol ingestion may disturb fat digestion and absorption by affecting gastric, intestinal, hepatic, and pancreatic functions. Involved mechanisms are not well understood. We examined in vitro ethanol effects on gastric and pancreatic lipolytic activity. Methods: Human gastric juice, pure gastric lipase, pancreatic lipase, colipase, carboxyl ester lipase, phospholipase A₂, and duodenal contents were a) preincubated at 37°C with ethanol (0–30%) and then assayed under normal conditions (pH-stat titration), or b) assayed in the presence of various ethanol concentrations (0–30%). Results: Ethanol reduced gastric and pancreatic lipolytic activities in a dose-dependent manner. The effect was more pronounced with alcohol present in the assay medium, with 5% ethanol reducing carboxyl ester lipase activity by 10%, gastric lipase activity by 20%, and pancreatic lipase activity by 46%. Colipase and phospholipase A₂ activities were only slightly affected by ethanol. Conclusions: Observed effects of ethanol on gastric and pancreatic lipases may be important when fat digestion is already impaired due to gastric, intestinal, hepatic, and/or pancreatic diseases.

Key Words:

• Colipase
• digestion
• ethanol
• gastric lipase
• pancreatic carboxyl ester lipase
• pancreatic lipase
• pancreatic phospholipase A₂