Intravenous fish oil emulsion attenuates total parenteral nutrition-induced cholestasis in newborn piglets

Total parenteral nutrition (TPN) causes intrahepatic cholestasis and membra ne phospholipid changes. Fatty acid (FA) composition of bile and hepatocyte phospholipid is influenced by dietary FA composition. We hypothesized that altering FA composition of i.v. lipid emulsions modifies 1) severity of TP N-induced cholestasis; 2) hepatocyte membrane composition and function; 3) bile flow and composition. Newborn piglets received either sow's milk, TPN with i.v. soybean oil or TPN with i.v. fish oil (FO). After 3 wk, basal and stimulated bile flow were measured after bolus injections of 20, 50, and 1 00 mu mol/kg of taurocholate (TCA). Bile was analyzed for bile acids, chole sterol, phospholipids, and phospholipid-FA. Sinusoidal and canalicular memb rane PL-FA, fluidity, and Na+/K+-ATPase were measured. Although the soybean oil-fed animals developed cholestasis, the FO and milk group had similar l iver and serum bilirubin. Basal and stimulated bile flow rates were impaire d in the soybean oil but not in the FO group. Hepatocyte membrane FA compos ition reflected dietary FA. Changes in sinusoidal and canalicular membrane fluidity and sinusoidal Na+/K+-ATPase activity did not explain the effect o f FO on TPN-induced cholestasis. Intravenous FO reduces TPN-induced cholest asis by unknown mechanisms.