Obligatory role of bile for the intestinal absorption of vitamin E

Abstract

Normal, white female rats subjected to cannulation of the abdominal thoracic duct have been utilized for a study on the essentiality of biliary and pancreatic secretions for the intestinal absorption of vitamin E. In all animals the thoracic duct lymph was collected. Some rats had the enterohepatic circulation undisturbed and in others bile or pancreatic juice or both were drained to the exterior by appropriate catheters in the common bile duct. On the first postoperative day, the animals received intragastrically an emulsion containing protein, carbohydrate, monoolein, 2 mg ofd,l‐α‐tocopheryl acetate plus 50 μC ofd,l‐α‐tocopheryl‐1’,2’‐3H‐acetate. The appearance of radioactive α‐tocopherol and its derivatives was determined in lymph, hourly, after emulsion administration. The obligatory role of bile in intestinal absorption ofd,l‐α‐tocopheryl‐1’,2’‐3H‐acetate has been established. Pancreatic juice seems to be necessary for the hydrolysis of the vitamin E acetate ester. The simultaneous infusion of bile and pancreatic juice promotes absorption of about 10% of the administered dose into the lymph. A chromatographic separation of the radioactive vitamin E fractions revealed that most of the vitamin E, which is actively transfered from the intestinal lumen to the lymph, is nonesterified. An oxidation product of α‐tocopherol, presumably itsp‐quinone, appears in small amounts in the lymph, but almost no labeled α‐tocopheryl acetate could be detected under these experimental conditions.

Tocopherol transport and absorption

“…The bile salts are synthesized by the liver and secreted into the small intestine from the gall bladder. The obligatory requirement of bile for the intestinal absorption of vitamin E has been demonstrated in patients with liver diseases and biliary obstruction (Harries & Muller, 1971a;Sokol et al 1987) and in experimental animals (Gallo-Torres, 1970;MacMahon & Thompson, 1970). Additional evidence for the importance of bile salts comes from in vitro studies using rat small intestinal slices (Pearson & Legge, 1972) or intestinal cells (Traber et al 19906).…”

Antioxidants vitamin E and C attenuate hepatic fibrosis in biliary-obstructed rats

“…Bile acids especially, enhance reactive oxygen species released by polymorphonuclear leukocytes [11] . In addition, intraluminal bile salt deficiency in extrahepatic biliary obstruction results in vitamin E malabsorption [12] . Serum and hepatic tissue levels of vitamin E are reduced threefold in biliary-obstructed rats [13] .…”

Influence of Selenium on the Time Distribution of Tritium-Labelled Tocopherol in Selected Tissues of the Rat

“…The cornell workers (Desai and Scott, 1965; Thompson and scott, 1970) used cr-tocopherol acetate, whereas in our studies s-tocopherol has been used. Gallo-Torres (1970) …”