Dietary induction of pancreatic cholesterol esterase: a regulatory cycle for the intestinal absorption of cholesterol

1996 ◽  
Vol 74 (2) ◽  
pp. 257-264 ◽  
Author(s):  
Terry Sasser ◽  
Chakradhar Buddhiraju ◽  
Vijaya B. Kumar ◽  
Angel Lopez-Candales ◽  
Jackie Grosjlos ◽  
...  
Keyword(s):  
Dietary Cholesterol ◽  
Cholesterol Absorption ◽  
Cholesterol Esterase ◽  
Intestinal Cholesterol Absorption ◽  
Sterol Esters ◽  
Mrna Induction ◽  
High Fraction ◽  
Dietary Sterol ◽  
Human Intestinal Cells

Atherosclerosis has a strong dietary basis without a proven molecular mechanism for cholesterol absorption. To investigate the potential role of pancreas in this process and its interaction with the two dietary forms of cholesterol (free and esterified), we undertook to study the role of pancreatic cholesterol esterase in cholesterol absorption. The results showed that (i) cholesterol esters contribute a disproportionately high fraction of absorbed dietary cholesterol, (ii) rates of intestinal cholesterol absorption are related to pancreatic cholesterol esterase activity, (iii) mRNA specific for pancreatic cholesterol esterase is induced 15-fold by dietary sterol esters and 10-fold by free sterol, (iv) the induction of cholesterol esterase mRNA is reversible, and (v) free cholesterol transport into cultured human intestinal cells is enhanced 300% by pancreatic cholesterol esterase. These data implicate pancreatic cholesterol esterase as pivotal in a metabolic loop under positive feedback control for the absorption of dietary cholesterol, whether free or esterified.Key words: cholesterol esterase, diet, transport, mRNA, induction.

Role of bile and pancreatic juice in cholesterol absorption and esterification

1964 ◽  
Vol 206 (1) ◽  
pp. 223-228 ◽  
Author(s):  
C. R. Borja ◽  
George V. Vahouny ◽  
C. R. Treadwell
Keyword(s):  
Pancreatic Juice ◽  
Bile Salts ◽  
Intestinal Tract ◽  
Dietary Cholesterol ◽  
Cholesterol Absorption ◽  
Cholesterol Esterase ◽  
Thoracic Duct Lymph ◽  
Intragastric Administration ◽  
Rate Limiting Step

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.

scholarly journals A role for NPC1 and NPC2 in intestinal cholesterol absorption – the hypothesis gutted

2007 ◽  
Vol 408 (1) ◽  
Author(s):  
Laura Liscum
Keyword(s):  
Endoplasmic Reticulum ◽  
Dietary Cholesterol ◽  
Cholesterol Absorption ◽  
Cholesterol Transport ◽  
Intestinal Epithelial ◽  
Intestinal Cholesterol Absorption ◽  
Biochemical Journal ◽  
Good Target ◽  
Type C ◽  
Niemann Pick

Dietary and biliary cholesterol are taken up by intestinal epithelial cells and transported to the endoplasmic reticulum. At the endoplasmic reticulum, cholesterol is esterified, packaged into chylomicrons and secreted into the lymph for delivery to the bloodstream. NPC1L1 (Niemann–Pick C1-like 1) is a protein on the enterocyte brush-border membrane that facilitates cholesterol absorption. Cholesterol's itinerary as it moves to the endoplasmic reticulum is unknown, as is the identity of any cellular proteins that facilitate the movement. Two proteins that play an important role in intracellular cholesterol transport and could potentially influence NPC1L1-mediated cholesterol uptake are NPC1 and NPC2 (Niemann–Pick type C disease proteins 1 and 2). In this issue of the Biochemical Journal, Dixit and colleagues show that the absence or presence of NPC1 and NPC2 has no effect on intestinal cholesterol absorption in the mouse. Thus neither protein fills the gap in our knowledge of intra-enterocyte cholesterol transport. Furthermore, the NPC1/NPC2 pathway would not be a good target for limiting the uptake of dietary cholesterol.

Role of intestinal sterol transporters Abcg5, Abcg8, and Npc1l1 in cholesterol absorption in mice: gender and age effects

2006 ◽  
Vol 290 (2) ◽  
pp. G269-G276 ◽  
Author(s):  
Li-Ping Duan ◽  
Helen H. Wang ◽  
Akira Ohashi ◽  
David Q.-H. Wang
Keyword(s):  
Molecular Mechanisms ◽  
Apical Membrane ◽  
Cholesterol Absorption ◽  
Absorption Efficiency ◽  
Biliary Cholesterol ◽  
Intestinal Cholesterol Absorption ◽  
Gender And Age ◽  
Multistep Process ◽  
17Β Estradiol

Recent studies have indicated that intestinal cholesterol absorption is a multistep process, which is regulated by multiple genes at the enterocyte level. However, the molecular mechanisms whereby there are gender differences in intestinal cholesterol absorption efficiency and the efficiency of cholesterol absorption increases with age have not yet been fully understood. To explore whether aging increases cholesterol absorption via intestinal sterol transporters, we studied the higher cholesterol-absorbing C57L/J vs. the lower cholesterol-absorbing AKR/J mice at 8 (young adult), 36 (older adult), and 50 (aged) wk of age. To test the hypothesis that estrogen receptor (ER )α plays an important regulatory role in cholesterol absorption, we investigated the gonadectomized mice of both genders treated with 17β-estradiol-releasing pellets at 0, 3, or 6 μg/day and antiestrogenic ICI 182,780 at 125 μg/day. We found that hepatic outputs of biliary cholesterol were significantly increased with age and in response to high levels of estrogen. Aging significantly enhances cholesterol absorption by suppressing expression of the jejunal and ileal sterol efflux transporters [ATP-binding cassette ( Abc) g5 and Abcg8] and upregulating expression of the putative duodenal and jejunal sterol influx transporter Npc1l1. Estrogen significantly augmented cholesterol absorption mostly due to an upregulated expression of intestinal Npc1l1, Abcg5, and Abcg8 via the intestinal ERα pathway, which can be fully abolished by the antagonist. We conclude that ERα activated by estrogen and aging enhances cholesterol absorption by increasing biliary lipid output and mediating intestinal sterol transporters favoring influx of intraluminal cholesterol molecules across the apical membrane of the enterocyte.

Role of Pancreatic Digestion in Cholesterol Absorption

1957 ◽  
Vol 190 (2) ◽  
pp. 214-220 ◽  
Author(s):  
T. M. Lin ◽  
Esko Karvinen ◽  
A. C. Ivy
Keyword(s):  
Fatty Acid ◽  
Pancreatic Juice ◽  
Essential Role ◽  
Corn Oil ◽  
Dietary Cholesterol ◽  
Cholesterol Absorption ◽  
Fatty Acid Esters ◽  
Acid Esters ◽  
Endogenous Cholesterol

The exclusion of pancreatic juice had no significant effect on elimination of endogenous cholesterol in the rat but increased it slightly in three dogs. Forty per cent of the dietary cholesterol was absorbed without and with pancreatic exclusion in the presence of a fat-free diet. Hence, pancreatic juice is not specifically necessary for the absorption of cholesterol. Pancreatic exclusion had no effect on the absorption of either dietary cholesterol or fatty acid, or both, when oleic and palmitic acid were fed. This indicates that any effect pancreatic exclusion may exert on cholesterol absorption when a fat containing diet is fed depends on the change in the utilization of the fat resulting from the exclusion. In the case of corn oil, triolein, trielaidin and tallow but not with tripalmitin, pancreatic exclusion was followed by an increased fecal elimination of both fatty acid and cholesterol. The increment of fatty acid elimination was large enough to dissolve the excess cholesterol excreted in the rats with pancreatic exclusion, except in the case of trielaidin. The only statistically significant decrease in the absorption of dietary cholesterol which resulted from pancreatic exclusion occurred when one of the unsaturated fatty acid esters, namely, corn oil, triolein, or trielaidin was the fat fed. These observations fail to show that pancreatic cholesterol esterase plays a specifically essential role in the absorption of free dietary cholesterol.

Dietary Sphingomyelin Metabolism and Roles in Gut Health and Cognitive Development

2021 ◽  
Author(s):  
Chenyu Jiang ◽  
Ling-Zhi Cheong ◽  
Xue Zhang ◽  
Abdelmoneim H Ali ◽  
Qingzhe Jin ◽  
...  
Keyword(s):  
Cognitive Development ◽  
Human Milk ◽  
Neural Development ◽  
Cholesterol Absorption ◽  
Gut Health ◽  
Intestinal Cholesterol Absorption ◽  
Cellular Signal ◽  
Term Functions

Abstract Sphingomyelin (SM) is a widely occurring sphingolipid that is a major plasma membrane constituent. Milk and dairy products are rich SM sources, and human milk has high SM content. Numerous studies have evaluated the roles of SM in maintaining cell membrane structure and cellular signal transduction. There has been a growing interest in exploring the role of dietary SM, especially from human milk, in imparting health benefits. This review focuses on recent publications regarding SM content in several dietary sources and dietary SM metabolism. SM digestion and absorption are slow and incomplete and mainly occur in the middle sections of the small intestine. This review also evaluates the effect of dietary SM on gut health and cognitive development. Studies indicate that SM may promote gut health by reducing intestinal cholesterol absorption in adults. However, there has been a lack of data supporting clinical trials. An association between milk SM and neural development is evident before childhood. Hence, additional studies and well-designed randomized controlled trials that incorporate dietary SM evaluation, SM metabolism, and its long-term functions on infants and children are required.

scholarly journals Dietary Plant Sterol Esters Must Be Hydrolyzed to Reduce Intestinal Cholesterol Absorption in Hamsters

2015 ◽  
Vol 145 (7) ◽  
pp. 1402-1407 ◽  
Author(s):  
Trevor J Carden ◽  
Jiliang Hang ◽  
Patrick H Dussault ◽  
Timothy P Carr
Keyword(s):  
Plant Sterol ◽  
Cholesterol Absorption ◽  
Intestinal Cholesterol Absorption ◽  
Sterol Esters

scholarly journals Dietary cholesterol lowers the activity of butyrylcholinesterase (EC3.1.1.8), but elevates that of esterase-1 (EC3.1.1.1) in plasma of rats

1993 ◽  
Vol 70 (3) ◽  
pp. 721-726 ◽  
Author(s):  
H. A. Van Lith ◽  
A. C. Beynen
Keyword(s):  
Cholesterol Metabolism ◽  
Plasma Cholesterol ◽  
Dietary Cholesterol ◽  
Cholesterol Absorption ◽  
Intestinal Cholesterol Absorption ◽  
Carbohydrate Source ◽  
Butyrylcholinesterase Activity

The question addressed is whether an increased intake of cholesterol affects esterase-1 (EC3.1.1.1; ES-1) and butyrylcholinesterase (EC3.1.1.8) activity in plasma. Rats were fed on a purified diet either without or with cholesterol (10 g/kg) added at the expense of the carbohydrate source. Dietary cholesterol significantly decreased plasma butyrylcholinesterase activity, but raised plasma ES-1 activity. Evidence is discussed, suggesting that plasma butyrylcholinesterase is involved in plasma cholesterol metabolism, whereas esterase-1 is involved in intestinal cholesterol absorption.

The role of cholesterol absorption and hepatic cholesterol content in high and low responses to dietary cholesterol and fat in pedigreed baboons (Papio species)

Metabolism ◽  
1993 ◽  
Vol 42 (6) ◽  
pp. 714-722 ◽  
Author(s):  
Rampratap S. Kushwaha ◽  
Karen S. Rice ◽  
Douglas S. Lewis ◽  
Henry C. McGill ◽  
K.D. Carey
Keyword(s):  
Dietary Cholesterol ◽  
Cholesterol Absorption ◽  
Cholesterol Content ◽  
Hepatic Cholesterol
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