Abstract
Inhibitors of cholesterol absorption have been sought for decades as a means to treat and prevent cardiovascular diseases (CVDs) associated with hypercholesterolemia. Ezetimibe is the one clear success story in this regard, and other compounds with similar efficacy continue to be sought. In the last decade, the laboratory mouse, with all its genetic power, has become the premier experimental model for discovering the mechanisms underlying cholesterol absorption and has become a critical tool for preclinical testing of potential pharmaceutical entities. This chapter briefly reviews the history of cholesterol absorption research and the various gene candidates that have come under consideration as drug targets. The most common and versatile method of measuring cholesterol absorption is described in detail along with important considerations when interpreting results, and an alternative method is also presented. In recent years, reverse cholesterol transport (RCT) has become an area of intense new interest for drug discovery since this process is now considered another key to reducing CVD risk. The ultimate measure of RCT is sterol excretion and a detailed description is given for measuring neutral and acidic fecal sterols and interpreting the results.
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References
Hui DY, Howles PN (2005) Molecular mechanisms of cholesterol absorption and transport in the intestine. Semin Cell Dev Biol 16:183–192
Levy E, Spahis S, Sinnett D, Peretti N, Maupas-Schwalm F et al (2007) Intestinal cholesterol transport proteins: an update and beyond. Curr Opin Lipidol 18:310–318
Hui DY, Labonté ED, Howles PN (2008) Development and physiological regulation of intestinal lipid absorption III. Intestinal transporters and cholesterol absorption. Am J Physiol Gastrointest Liver Physiol 294:839–843
Westergaard H, Dietschy JM (1976) The mechanism whereby bile acid micelles increase the rate of fatty acid and cholesterol uptake into the intestinal mucosal cells. J Clin Invest 58:97–108
Thurnhofer H, Hauser H (1990) Uptake of cholesterol by small intestinal brush border membrane is protein-mediated. Biochemistry 29:2142–2148
Borja CR, Vahouny GV, Treadwell CR (1964) Role of bile and pancreatic juice in cholesterol absorption and esterification. Am J Physiol 206:223–228
Gallo LL, Clark SB, Myers S, Vahouny GV (1984) Cholesterol absorption in rat intestine: role of cholesterol esterase and acyl coenzyme A:cholesterol acyl transferase. J Lipid Res 25:604–612
Fernandez E, Borgström B (1989) Effects of tetrahydrolipstatin, a lipase inhibitor, on absorption of fat from the intestine of the rat. Biochim Biophys Acta 1001:249–255
McKean ML, Commons TJ, Berens MS, Hsu PL, Ackerman DM et al (1992) Effect of inhibitors of pancreatic cholesterol ester hydrolase (PCEH) on 14C-cholesterol absorption in animal models. FASEB J 6:A1388
Krause BR, Sliskovic DR, Anderson M, Homan R (1998) Lipid-lowering effects of WAY-121,898, an inhibitor of pancreatic cholesteryl ester hydrolase. Lipids 33:489–498
Howles PN, Carter CP, Hui DY (1996) Dietary free and esterified cholesterol absorption in cholesterol esterase (bile salt-stimulated lipase) gene-targeted mice. J Biol Chem 271:7196–7202
Weng W, Li L, van Bennekum AM, Potter SH, Harrison EH et al (1999) Intestinal absorption of dietary cholesteryl ester is decreased but retinyl ester absorption is normal in carboxyl ester lipase knockout mice. Biochemistry 38:4143–4149
Camarota LM, Chapman JM, Hui DY, Howles PN (2004) Carboxyl ester lipase cofractionates with scavenger receptor BI in hepatocyte lipid rafts and enhances selective uptake and hydrolysis of choelsteryl esters from HDL3. J Biol Chem 279:27599–27606
Chaikoff IL, Bloom B, Siperstein MD, Kiyasu JY, Reinhardt WO et al (1952) C14-cholesterol I: lymphatic transport of absorbed cholesterol-4-C14. J Biol Chem 194:407–412
Heider JG, Pickens CE, Kelly LA (1983) Role of acyl CoA:cholesterol acyltransferase in cholesterol absorption and its inhibition by 57–118 in the rabbit. J Lipid Res 24:1127–1134
Clark SB, Tercyak AM (1984) Reduced cholesterol transmucosal transport in rats with inhibited mucosal acyl CoA:cholesterol acyltransferase and normal pancreatic function. J Lipid Res 25:148–159
Gallo LL, Wadsworth JA, Vahouny GV (1987) Normal cholesterol absorption in rats deficient in intestinal acyl coenzyme A:cholesterol acyltransferase activity. J Lipid Res 28:381–387
Buhman KK, Accad M, Novak S, Choi RS, Wong JS et al (2000) Resistance to diet-induced hypercholesterolemia and gallstone formation in ACAT2-deficient mice. Nat Med 6:1341–1347
Yagu H, Kitamine T, Osuga J, Tozawa R, Chen Z et al (2000) Absence of ACAT-1 attenuates atherosclerosis but causes dry eye and cutaneous xanthomatosis in mice with congenital hyperlipidemia. J Biol Chem 275:21324–21330
Leon C, Hill JS, Wasan KM (2005) Potential role of acyl-coenzyme A:cholesterol transferase (ACAT) inhibitors as hypolipidemic and antiatherosclerosis drugs. Pharm Res 22:1578–1588
Rudel LL, Lee RG, Parini P (2005) ACAT2 is a target for treatment of coronary heart disease associated with hyperchoelsterolemia. Arterioscler Thromb Vasc Biol 25:1112–1118
Lada AT, Davis M, Kent C, Chapman J, Tomoda H et al (2004) Identification of ACAT1- and ACAT2-specific inhibitors using a novel, cell-based fluorescence assay: individual ACAT uniqueness. J Lipid Res 45:378–386
VanHeek M, France CF, Compton DS, McLeon RL, Yumibe NP et al (1997) In vivo metabolism-based discovery of a potent absorption cholesterol inhibitor, SCH58235, in the rat, and rhesus monkey through the identification of the active metabolites of SCH48461. J Pharmacol Exp Therap 283:157–163
Altmann SW, Davis HR, Zhu L, Yao X, Hoos LM et al (2004) Niemann-Pick C1 like 1 protein is critical for intestinal cholesterol absorption. Science 303:1201–1204
Garcia-Calvo M, Lisnock HG, Bull BE, Hawes DA, Burnett MP et al (2005) The target of ezetimibe is Niemann-Pick C1-like 1 (NPC1L1). Proc Natl Acad Sci U S A 102:8132–8137
Ziajka PE, Reis M, Kreul S, King H (2004) Initial low-density lipoprotein response to statin therapy predicts subsequent low-density lipoprotein response to the addition of ezetimibe. Am J Cardiol 93:779–780
Richmond BL, Boileau AC, Zheng S, Huggins KW, Gramholm NA et al (2001) Compensatory phospholipid digestion is required for cholesterol absorption in pancreatic phospholipase A(2)-deficient mice. Gastroenterology 120:1193–1202
Huggins KW, Boileau AC, Hui DY (2002) Protection against diet-induced obesity and insulin resistance in group 1B PLA2 deficient mice. Am J Physiol Endocrinol Metab 283:E994–E1001
Homan R, Hamelehle KL (1998) Phospholipase A2 relieves phosphatidylcholine inhibition of micellar cholesterol absorption and transport by human intestinal cell line Caco-2. J Lipid Res 39:1197–1209
Huggins KW, Camarota LM, Howles PN, Hui DY (2003) Pancreatic triglyceride lipase deficiency minimally affects dietary fat absorption but dramatically decreases dietary cholesterol absorption in mice. J Biol Chem 278:42899–42905
Mittendorf B, Ostlund RE, Patterson BW, Klein S (2001) Orlistat inhibits dietary cholesterol absorption. Obes Res 9:599–604
Drew BS, Dixon AF, Drew JB (2007) Obesity management: update on orlistat. Vasc Health Risk Manag 3:817–821
Quintão E, Grundy SM, Ahrens EH (1971) An evaluation of four methods for measuring cholesterol absorption by the intestine in man. J Lipid Res 12:221–232
Sanders DJ, Minter HJ, Howes D, Hepburn PA (2000) The safety evaluation of phytosterol esters. Part 6. The comparative absorption and tissue distribution of phytosterols in the rat. Food Chem Toxicol 38:485–491
Igel M, Giesa U, Lutjohann D, von Bergmann K (2003) Comparison of the intestinal uptake of cholesterol, plant sterols, and stanols in mice. J Lipid Res 44:533–538
Kastelein JJ, van Leuven SI, Burgess L, Evans GW, Kuivenhoven JA, Barter PJ, Revkin JH, Grobbee DE, Riley WA, Shear CL, Duggan WT, Bots ML, RADIANCE 1 investigators (2007) Effect of torcetrapib on carotid atherosclerosis in familial hypercholesterolemia. N Engl J Med 356:1620–1630
Forrester JS, Makkar R, Shah PK (2005) Increasing high-density lipoprotein cholesterol in dyslipidemia by cholesteryl ester transfer protein inhibition. Circulation 111:1847–1854
Tchoua U, D'Souza W, Mukhamedova N, Blum D, Niesor E, Mizrahi J, Maugeais C, Sviridov D (2008) The effect of cholesteryl ester transfer protein overexpression and inhibition on reverse cholesterol transport. Cardiovasc Res 77:732–739
Post SM, de Crom R, van Haperen R, van Tol A, Princen HM (2003) Increased fecal bile acid excretion in transgenic mice with elevated expression of human phospholipid transfer protein. Arterioscler Thromb Vasc Biol 23:892–897
Zhang YZ, Zanotti I, Reilly MP, Glick JM, Rothblat GH et al (2003) Overexpression of apolipoprotein A-I promotes reverse cholesterol transport from macrophages to feces in vivo. Circulation 108:661–663
Carter CP, Howles PN, Hui DY (1997) Genetic variation in cholesterol absorption efficiency among inbred strains of mice. J Nutr 127:1344–1348
Zilversmit DB, Hughes LB (1974) Validation of a dual-isotope plasma ratio for measurement of cholesterol absorption in rats. J Lipid Res 15:465–473
Millar JS, Cromley DA, McCoy MG, Rader DJ, Billheimer JT (2005) Determining hepatic triglyceride production in mice: comparison of poloxamer 407 with Triton WR-1339. J Lipid Res 46:2023–2028
Jandacek RJ, Heubi JE, Tso P (2004) A novel, noninvasive method for the measurement of intestinal fat absorption. Gastroenterology 127:139–144
LaBonté ED, Camarota LM, Rojas JC, Jandacek RJ, Gilham DE et al (2008) Reduced absorption of saturated fatty acids and resistance to diet-induced obesity and diabetes by ezetimibe-treated and Npc1l1 −/− mice. Am J Physiol Gastrointest Liver Physiol 295:G776–G783
Osono Y, Woollett LA, Herz J, Dietschy JM (1995) Role of the low density lipoprotein receptor in the flux of cholesterol across the tissues of the mouse. J Clin Invest 95:1124–1132
Acknowledgments
This work was supported by NIH grants R01HL078900 and R01DK077170-ARRA.
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Howles, P.N. (2016). Cholesterol Absorption and Metabolism. In: Proetzel, G., Wiles, M. (eds) Mouse Models for Drug Discovery. Methods in Molecular Biology, vol 1438. Humana Press, New York, NY. https://doi.org/10.1007/978-1-4939-3661-8_11
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DOI: https://doi.org/10.1007/978-1-4939-3661-8_11
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