Heparin-modulated Binding of Pancreatic Lipase and Uptake of Hydrolyzed Triglycerides in the Intestine

Bosner, Matthew S.; Gulick, Tod; Riley, D. J. S.; Spilburg, Curtis A.; Lange, Louis G.

doi:10.1016/s0021-9258(19)47056-7

Cited by 32 publications

(11 citation statements)

References 10 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…One experiment describing the 3Hhexadecylglycerol absorption at 4 0 C is included, emphasizing the lack of temperature dependence of 3H-hexadecylglycerol absorption (open circles, Figure 3). Also included in Figure 3 is the pseudo-first-order rate constant obtained with enterocytes treated with heparin, indicating that removal of triacylglycerol lipase from BBM (Bosner et al, 1989) did not impair 3H-hexadecylglycerol absorption (triangle, Figure 3).…”

Section: Resultsmentioning

confidence: 99%

See 1 more Smart Citation

Absorption of Monoacylglycerols by Small Intestinal Brush Border Membrane

Schulthess¹,

Lipka²,

Compassi³

et al. 1994

Biochemistry

View full text Add to dashboard Cite

The absorption of monoacylglycerol by small intestinal brush border membrane is a passive process, i.e., the movement of monoacylglycerol from small unilamellar phospholipid vesicles as donor particles through the aqueous medium and the incorporation into the outer monolayer of the lipid bilayer of the brush border membrane are passive processes involving diffusion of the lipid along a concentration gradient. Small unilamellar vesicles of egg phosphatidylcholine containing 1 mol% of radiolabeled hexadecylglycerol were used as donor, and rabbit small intestinal brush border membrane vesicles or intact enterocytes isolated from pig jejunum, as acceptor. Hexadecylglycerol was employed as a lipase-resistant model compound for monoacylglycerols. Both acceptor membranes behave similarly in terms of hexadecylglycerol absorption: the kinetics of hexadecylglycerol absorption are biphasic. The initial fast phase is due to the movement of hexadecylglycerol from the donor particle through the aqueous medium to the outer lipid monolayer of the acceptor membrane, and the second slow phase probably involves the flip-flop motion of hexadecylglycerol from the outer to the inner monolayer of the acceptor membrane. The values for the pseudo-first-order rate constants of the initial fast phase for hexadecylglycerol absorption are relatively large and primarily determined by the high solubility (cmc) of hexadecylglycerol in aqueous media. The pseudo-first-order rate constants depend linearly on the protein (lipid) concentration of the acceptor membrane, indicating that the on rate of the hexadecylglycerol into the brush border membrane is rate limiting. The mechanism of the hexadecylglycerol absorption involves mainly monomer diffusion and probably collision-induced transfer.

show abstract

Section: Resultsmentioning

confidence: 99%

“…Heparin was reported to liberate BBM-associated enzymes such as triacylglycerol lipase (Bosner et al, 1989). Since these proteins have been implicated in lipid digestion and absorption, the lack of an effect of heparin eliminates these proteins as direct contributors to monoacylglycerol absorption.…”

Section: Discussionmentioning

confidence: 99%

Absorption of Monoacylglycerols by Small Intestinal Brush Border Membrane

Schulthess¹,

Lipka²,

Compassi³

et al. 1994

Biochemistry

View full text Add to dashboard Cite

show abstract

“…Other lipid binding proteins, such as 100 nM pancreatic triglyceride lipase or 100 nM liver fatty acid binding protein (Teerlink et al, 1984), have no effect on cholesterol uptake (Figure 1 A). Importantly, triglyceride lipase also binds to heparin (Bosner et al, 1989) so the enhanced cholesterol absorption seen with CEase is not due to a modification of the thickness/structure of the unstirred water layer. Therefore, these results show that, under physiological conditions, pancreatic CEase specifically and significantly stimulates cholesterol uptake into Caco-2 cells.…”

Section: Resultsmentioning

confidence: 99%

“…We have suggested that anchoring mechanisms may exist to juxtapose neutral lipid binding proteins or enzymes to the plasma membrane to facilitate absorption. Indeed, this appears to be the case for movement of cholesterol and free fatty acid across the brush border membrane via anchored pancreatic cholesterol esterase (CEase)1 and triglyceride lipase (Bosner et al, 1988(Bosner et al, ,1989. In these examples, as well as for lipoprotein lipase, immobilization occurs by a high-affinity, specific interaction with membrane proteoglycans.…”

mentioning

confidence: 99%

Cholesterol transport function of pancreatic cholesterol esterase: Directed sterol uptake and esterification in enterocytes

López‐Candales¹,

Bosner²,

Spilburg³

et al. 1993

Biochemistry

View full text Add to dashboard Cite

We have recently hypothesized that neutral lipids can, in part, move across biological membranes via a mechanism involving enzymes anchored to membrane proteoglycans such as those found in the brush border of the enterocyte [Bosner, M. S., Gulick, T., Riley, D. J. S., Spilburg, C. A., & Lange, L. G. (1988) Proc. Natl. Acad. Sci. U.S.A. 85, 7438-7442]. Present results now show a subsequent, essential protein-mediated sorting of neutral lipids for further intracellular metabolism. Thus, in the absence of enzyme, 0.002 pmol of cellular ester appeared after 2 h, and its level increased only 3.5-fold after 12 h. However, in the presence of cholesterol esterase, the level of cholesterol ester increased 39-fold in the same time period, indicating that the enzyme-mediated uptake accounts for 10-fold greater ester synthesis than that from basal absorption. Kinetic analysis reveals that both enzyme-mediated and background absorption depend on taurocholate concentration and are second-order reactions more likely dependent on collision than diffusion. Other lipid-recognizing proteins such as pancreatic triglyceride lipase and the intestinal fatty acid binding protein are not stimulatory to intracellular cholesterol processing. Taken together, these data suggest that pancreatic cholesterol esterase and possibly other proteoglycan-binding extracellular enzymes of neutral lipid metabolism may facilitate movement of neutral lipids into the plasma membrane and direct them into functional intracellular sites.

show abstract

“…Therefore, the question is how is BSDL transmurally transported from the blood to the urine. One possibility is that BSDL first binds to the glycocalyx of the glomerular endothelium via its heparin-binding site 32 or its cationic clusters. 33 It may then diffuse through selective pores, concentrate at the level of proteoglycans of the basement membrane still by means of its affinity for heparans, and finally filtrate through the slit diaphragm.…”

Section: Discussionmentioning

confidence: 99%

Detection of bile salt-dependent lipase, a 110 kDa pancreatic protein, in urines of healthy subjects

Comte

Franceschi

Sadoulet

et al. 2006

Kidney International

View full text Add to dashboard Cite

Bile salt-dependent lipase (BSDL), a 110 kDa glycoprotein secreted by the pancreatic acinar cells, participates in the duodenal hydrolysis of dietary lipid esters. Recent in vitro and in vivo studies demonstrated that the BSDL reaches the blood via a transcytosis motion through enterocytes, suggesting that this enzyme may play a role in vascular biology. Once in the blood, BSDL should be eliminated. We address the hypothesis that BSDL may be filtered by the glomerulus and eliminated in urines. Immunological methods and proteomic were used to detect and to characterize BSDL in urine. The immunoreactive form of BSDL was detected in urines of 36 male subjects devoid of renal failure. Proteomic demonstrated that the immunoreactive protein is BSDL. Experiments using a monoclonal antibody to the oncofetal glycoform of pancreatic BSDL suggested that the protein is not expressed by renal cells but originates from the pancreas via circulation. We demonstrate that under normal physiological conditions, BSDL, a high-molecular weight blood glycoprotein, can be filtered by the renal glomerulus to be eliminated in urines.

show abstract

Heparin-modulated Binding of Pancreatic Lipase and Uptake of Hydrolyzed Triglycerides in the Intestine

Cited by 32 publications

References 10 publications

Absorption of Monoacylglycerols by Small Intestinal Brush Border Membrane

Absorption of Monoacylglycerols by Small Intestinal Brush Border Membrane

Cholesterol transport function of pancreatic cholesterol esterase: Directed sterol uptake and esterification in enterocytes

Detection of bile salt-dependent lipase, a 110 kDa pancreatic protein, in urines of healthy subjects

Contact Info

Product

Resources

About