Role of bile and pancreatic juice in cholesterol absorption and esterification

Abstract

Absence of bile and pancreatic juice in the intestinal tract totally abolished absorption of cholesterol-4-C14 into thoracic duct lymph. Similarly, intestinal cholesterol esterase activity approached zero in animals lacking both bile and pancreatic juice. Intestinal cholesterol esterase could still be demonstrated in animals deprived of pancreatic juice, but which received an infusion or intragastric administration of bile salts. Absorption of cholesterol was shown to occur even in the complete absence of pancreatic juice, provided bile salts were present in the intestinal tract. Some synthesis of cholesterol esterase by the intestinal or reactivation of residual cholesterol esterase in the presence of bile salts is postulated. Thus, pancreatic secretion is not absolutely required for cholesterol absorption, although it has a stimulating effect in the presence of bile salts. This effect is attributed to its cholesterol esterase content. In the presence of bile salts, the process of esterification is postulated to be a rate-limiting step during intestinal absorption of dietary cholesterol.

Purification and Characterization of a Novel Cholesterol Esterase fromPseudomonas aeruginosa, with Its Application to Cleaning Lipid-stained Contact Lenses

“…[1][2][3][4][5] In addition to cholesteryl esters, acylglycerols, retinyl esters, vitamin esters, and phospholipids are also among the physiological substrates of the enzyme. 6) On the other hand, in spite of the widespread distribution and variety of sterols and fatty acids in fungi and yeasts, production of microbial cholesterol esterase has been demonstrated only from Pseudomonas (P.) ‰uorescens,…”

Tissue and species differences in bile salt-dependent neutral cholesteryl ester hydrolase activity and gene expression.

“…Diversion of pancreatic secretions in rats results in a rapid and significant decline in CEH activity in the intestine. 5 ' 27 Gallo et al 5 and de la Porte et al, 28 using immunological and ultrastructural methods, respectively, have shown that at least part of the intracellular CEH pool in rat enterocytes was derived from uptake of pancreatic enzyme from the intestinal lumen. The intracellular enzyme is catalytically active and can be exported from the cells into the mesenteric lymph (References 5 and 29 and R. Zolfaghari and E. Fisher, unpublished observations).…”

Factors Affecting Intestinal Absorption of Cholesterol and Plant Sterols and Stanols

“…It was suggested that cholesterol esterase accelerates intestinal absorption and esterification of unesterified cholesterol 26,27 . Gallo et al reported that depletion of cholesterol esterase in the intestinal lumen following antibody administration led to a reduction of lymphatic cholesterol absorption in rats 28 .…”