HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Full Text (PDF) Submit a Letter to Editor Alert me when this article is cited Alert me when eLetters are posted Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Request Permissions Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Hime, N. J. Articles by Rye, K.-A. Search for Related Content PubMed PubMed Citation Articles by Hime, N. J. Articles by Rye, K.-A. Social Bookmarking                      What's this?

J Biol Chem, Vol. 273, Issue 42, 27191-27198, October 16, 1998

The Influence of Apolipoproteins on the Hepatic Lipase-mediated Hydrolysis of High Density Lipoprotein Phospholipid and Triacylglycerol

Neil J. Hime^§, Philip J. Barter^§, and Kerry-Anne Rye^§

From the  Department of Medicine, University of Adelaide and  Division of Cardiovascular Services, Royal Adelaide Hospital, Adelaide, South Australia, Australia 5000 and the ^§ Lipid Research Laboratory, The Hanson Centre for Cancer Research, Frome Road, Adelaide, South Australia, Australia 5000

This study describes the influence of apolipoproteins on the hepatic lipase (HL)-mediated hydrolysis of phospholipids and triacylglycerol in high density lipoproteins (HDL). HL-mediated hydrolysis was assessed in well characterized, homogeneous preparations of spherical reconstituted high density lipoproteins (rHDL). The rHDL were comparable in size and lipid composition and contained either apoA-I ((A-I)rHDL) or apoA-II ((A-II)rHDL) as their sole apolipoprotein constituent. Preparations of rHDL containing only cholesteryl esters (CE) in their core, (A-I/CE)rHDL and (A-II/CE)rHDL, were used to assess phospholipid hydrolysis. Preparations of rHDL that contained triacylglycerol as their predominant core lipid, (A-I/TG)rHDL and (A-II/TG)rHDL, were used to assess both triacylglycerol and phospholipid hydrolysis. The rHDL contained trace amounts of either radiolabeled phospholipid or radiolabeled triacylglycerol. Hydrolysis was measured as the release of radiolabeled nonesterified fatty acids (NEFA) from the rHDL. Kinetic analysis showed that HL had a greater affinity for the phospholipids in (A-II/CE)rHDL (K_m(app) = 0.2 mM) than in (A-I/CE)rHDL (K_m(app) = 3.1 mM). This was also evident when hydrolysis was measured directly by quantitating NEFA mass. HL also had a greater affinity for the phospholipids and triacylglycerol in (A-II/TG)rHDL than in (A-I/TG)rHDL. The V_max for phospholipid hydrolysis was, by contrast, greater for (A-I/CE)rHDL than for (A-II/CE)rHDL: 309.3 versus 49.1 nmol of NEFA formed/ml of HL/h. Comparable V_max values were obtained for the hydrolysis of the phospholipids in (A-II/TG)rHDL and (A-I/TG)rHDL. In the case of triacylglycerol hydrolysis, the respective V_max values for (A-I/TG)rHDL and (A-II/TG)rHDL were 1154.8 and 240.2 nmol of NEFA formed/ml of HL/h. These results show that apolipoproteins have a major influence on the kinetics of HL-mediated phospholipid and triacylglycerol hydrolysis in rHDL.

CiteULike

Complore

Connotea

Del.icio.us

Digg

Reddit

Technorati

This article has been cited by other articles:

				K.-A. Rye, C. A. Bursill, G. Lambert, F. Tabet, and P. J. Barter The metabolism and anti-atherogenic properties of HDL J. Lipid Res., April 1, 2009; 50(Supplement): S195 - S200. [Abstract] [Full Text] [PDF]

				N. Settasatian, P. J. Barter, and K.-A. Rye Remodeling of apolipoprotein E-containing spherical reconstituted high density lipoproteins by phospholipid transfer protein J. Lipid Res., January 1, 2008; 49(1): 115 - 126. [Abstract] [Full Text] [PDF]

				L. Freeman, M. J. A. Amar, R. Shamburek, B. Paigen, H. B. Brewer Jr., S. Santamarina-Fojo, and H. Gonzalez-Navarro Lipolytic and ligand-binding functions of hepatic lipase protect against atherosclerosis in LDL receptor-deficient mice J. Lipid Res., January 1, 2007; 48(1): 104 - 113. [Abstract] [Full Text] [PDF]

				G. C. Shearer, J. W. Newman, B. D. Hammock, and G. A. Kaysen Graded Effects of Proteinuria on HDL Structure in Nephrotic Rats J. Am. Soc. Nephrol., May 1, 2005; 16(5): 1309 - 1319. [Abstract] [Full Text] [PDF]

				J. Boucher, T. A. Ramsamy, S. Braschi, D. Sahoo, T. A-M. Neville, and D. L. Sparks Apolipoprotein A-II regulates HDL stability and affects hepatic lipase association and activity J. Lipid Res., May 1, 2004; 45(5): 849 - 858. [Abstract] [Full Text] [PDF]

				M. C. Cheung, S. D. Sibley, J. P. Palmer, J. F. Oram, and J. D. Brunzell Lipoprotein lipase and hepatic lipase: their relationship with HDL subspecies Lp(A-I) and Lp(A-I,A-II) J. Lipid Res., August 1, 2003; 44(8): 1552 - 1558. [Abstract] [Full Text] [PDF]

				K. Conde-Knape, A. Bensadoun, J. H. Sobel, J. S. Cohn, and N. S. Shachter Overexpression of apoC-I in apoE-null mice: severe hypertriglyceridemia due to inhibition of hepatic lipase J. Lipid Res., December 1, 2002; 43(12): 2136 - 2145. [Abstract] [Full Text] [PDF]

				P. Kee, K.-A. Rye, J. L. Taylor, P. H. R. Barrett, and P. J. Barter Metabolism of ApoA-I as Lipid-Free Protein or as Component of Discoidal and Spherical Reconstituted HDLs: Studies in Wild-Type and Hepatic Lipase Transgenic Rabbits Arterioscler. Thromb. Vasc. Biol., November 1, 2002; 22(11): 1912 - 1917. [Abstract] [Full Text] [PDF]

				F. Blanco-Vaca, J. C. Escola-Gil, J. M. Martin-Campos, and J. Julve Role of apoA-II in lipid metabolism and atherosclerosis: advances in the study of an enigmatic protein J. Lipid Res., November 1, 2001; 42(11): 1727 - 1739. [Abstract] [Full Text] [PDF]

				C. C. Hedrick, L. W. Castellani, H. Wong, and A. J. Lusis In vivo interactions of apoA-II, apoA-I, and hepatic lipase contributing to HDL structure and antiatherogenic functions J. Lipid Res., April 1, 2001; 42(4): 563 - 570. [Abstract] [Full Text]

				J. C. Escolà-Gil, J. Julve, A. Marzal-Casacuberta, J. Ordóñez-Llanos, F. González-Sastre, and F. Blanco-Vaca ApoA-II expression in CETP transgenic mice increases VLDL production and impairs VLDL clearance J. Lipid Res., February 1, 2001; 42(2): 241 - 248. [Abstract] [Full Text]

				K.-A. Rye and M. N. Duong Influence of phospholipid depletion on the size, structure, and remodeling of reconstituted high density lipoproteins J. Lipid Res., October 1, 2000; 41(10): 1640 - 1650. [Abstract] [Full Text]

				K. A. Dugi, M. J. A. Amar, C. C. Haudenschild, R. D. Shamburek, A. Bensadoun, R. F. Hoyt Jr, J. Fruchart-Najib, Z. Madj, H. B. Brewer Jr, and S. Santamarina-Fojo In Vivo Evidence for Both Lipolytic and Nonlipolytic Function of Hepatic Lipase in the Metabolism of HDL Arterioscler. Thromb. Vasc. Biol., March 1, 2000; 20(3): 793 - 800. [Abstract] [Full Text] [PDF]

				W. Weng, N. A. Brandenburg, S. Zhong, J. Halkias, L. Wu, X.-c. Jiang, A. Tall, and J. L. Breslow ApoA-II maintains HDL levels in part by inhibition of hepatic lipase: studies in apoA-II and hepatic lipase double knockout mice J. Lipid Res., June 1, 1999; 40(6): 1064 - 1070. [Abstract] [Full Text]

				T. A. Ramsamy, T. A.-M. Neville, B. M. Chauhan, D. Aggarwal, and D. L. Sparks Apolipoprotein A-I Regulates Lipid Hydrolysis by Hepatic Lipase J. Biol. Chem., October 20, 2000; 275(43): 33480 - 33486. [Abstract] [Full Text] [PDF]