Hepatic lipase and HDL metabolism

Phospholipid transfer protein (PLTP), hepatic lipase (HL), and lipoprotein lipase (LPL) have all been reported to be intricately involved in HDL metabolism but the effect of PLTP on the apolipoprotein B-containing lipoproteins relative to that of HL and LPL has not been established. Due to our previous observation of a positive correlation of PLTP activity with plasma apoB and LDL cholesterol, the relationship of PLTP with the LDL subfractions was investigated and compared with that of HL and LPL. Plasma lipoproteins from 50 premenopausal women were fractionated by density gradient ultracentrifugation. Correlations were calculated between the cholesterol concentration of each fraction and plasma PLTP, HL, and LPL activity. Plasma PLTP activity was highly, positively, and selectively correlated with the cholesterol concentration of the buoyant LDL/dense IDL fractions, yet demonstrated a complete absence of an association with the dense LDL fractions. In contrast, HL was positively correlated with the dense LDL fractions but showed no association with buoyant LDL. LPL was also positively correlated with several buoyant LDL fractions; however, the correlations were weaker than those of PLTP. PLTP and LPL were positively correlated and HL was negatively correlated with HDL fractions.The results suggest that PLTP and HL may be important and independent determinants of the LDL subpopulation density distributions.

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The complementary roles of hepatic lipase and endothelial lipase in HDL metabolism

Atherosclerosis Supplements ◽

10.1016/s1567-5688(02)80614-6 ◽

2002 ◽

Vol 3 (2) ◽

pp. 198

Keyword(s):

Hepatic Lipase ◽

Endothelial Lipase ◽

Hdl Metabolism

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Effect of Thyroid Dysfunction on High-Density Lipoprotein Subfraction Metabolism: Roles of Hepatic Lipase and Cholesteryl Ester Transfer Protein1

The Journal of Clinical Endocrinology & Metabolism ◽

10.1210/jcem.83.8.4938 ◽

1998 ◽

Vol 83 (8) ◽

pp. 2921-2924 ◽

Cited By ~ 1

Author(s):

K. C. B. Tan ◽

S. W. M. Shiu ◽

A. W. C. Kung.

Keyword(s):

High Density Lipoprotein ◽

Cholesteryl Ester ◽

Lipoprotein Lipase ◽

Thyroid Dysfunction ◽

Hepatic Lipase ◽

Density Lipoprotein ◽

High Density ◽

Free T4 ◽

Hdl Metabolism ◽

Hypothyroid Patients

abstract To investigate the effect of thyroid dysfunction on high-density lipoprotein (HDL) metabolism, we measured HDL subfractions, apolipoprotein A-I containing particles (LpA-I and LpA-I:A-II), and the activities of enzymes involved in the remodeling and metabolism of HDL[ namely hepatic lipase (HL), lipoprotein lipase, and cholesteryl ester transfer protein (CETP)] in 18 hyperthyroid and 17 hypothyroid patients before and after treatment. HDL was subfractionated by density gradient ultracentrifugation, and LpA-I was analyzed by electroimmunodiffusion. The major changes were found in the HDL2 subfraction and in LpA-I particles. HDL2-C and LpA-I were reduced in hyperthyroidism (P < 0.01, P < 0.05, respectively) and increased in hypothyroidism (both P < 0.05) compared with their respective euthyroid matched controls. Changes in HDL2-cholesterol were reversed after treatment in both hyper- and hypothyroid patients, and LpA-I also decreased in the hypothyroid patients after treatment. HL (P < 0.05) and CETP activities (P < 0.05) were elevated in hyperthyroidism and reduced in hypothyroidism (P < 0.05, P < 0.01 respectively) and both were related to free T4 levels. The changes in HDL2-C and LpA-I correlated significantly with changes in HL after treatment but not with CETP or lipoprotein lipase. In summary, HDL metabolism was altered in thyroid dysfunction, and the effect of thyroid hormone on HDL was mediated mainly via its effect on HL activity.

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Role of hepatic lipase and cholesteryl ester transfer protein in HDL metabolism

Atherosclerosis ◽

10.1016/0021-9150(94)94354-0 ◽

1994 ◽

Vol 109 (1-2) ◽

pp. 338 ◽

Cited By ~ 2

Author(s):

P.J. Barter ◽

H.-Q. Liang ◽

A.M. Clay ◽

K.-A. Rye

Keyword(s):

Cholesteryl Ester ◽

Cholesteryl Ester Transfer Protein ◽

Hepatic Lipase ◽

Transfer Protein ◽

Hdl Metabolism

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Lipoprotein distribution and serum concentrations of 7α-hydroxy-4-cholesten-3-one and bile acids: effects of monogenic disturbances in high-density lipoprotein metabolism

Clinical Science ◽

10.1042/cs20110482 ◽

2011 ◽

Vol 122 (8) ◽

pp. 385-400 ◽

Cited By ~ 4

Author(s):

Carine Steiner ◽

Adriaan G. Holleboom ◽

Ratna Karuna ◽

Mohammad M. Motazacker ◽

Jan Albert Kuivenhoven ◽

...

Keyword(s):

High Density Lipoprotein ◽

Hepatic Lipase ◽

Plasma Concentrations ◽

Density Lipoprotein ◽

High Density ◽

Low Density ◽

Serum Concentrations ◽

Very Low Density Lipoproteins ◽

Hdl Metabolism ◽

Lipoprotein Distribution

BA (bile acid) formation is considered an important final step in RCT (reverse cholesterol transport). HDL (high-density lipoprotein) has been reported to transport BAs. We therefore investigated the effects of monogenic disturbances in human HDL metabolism on serum concentrations and lipoprotein distributions of the major 15 BA species and their precursor C4 (7α-hydroxy-4-cholesten-3-one). In normolipidaemic plasma, approximately 84%, 11% and 5% of BAs were recovered in the LPDS (lipoprotein-depleted serum), HDL and the combined LDL (low-density lipoprotein)/VLDL (very-low-density lipoproteins) fraction respectively. Conjugated BAs were slightly over-represented in HDL. For C4, the respective percentages were 23%, 21% and 56% (41% in LDL and 15% in VLDL) respectively. Compared with unaffected family members, neither HDL-C (HDL-cholesterol)-decreasing mutations in the genes APOA1 [encoding ApoA-I (apolipoprotein A-I], ABCA1 (ATP-binding cassette transporter A1) or LCAT (lecithin:cholesterol acyltransferase) nor HDL-C-increasing mutations in the genes CETP (cholesteryl ester transfer protein) or LIPC (hepatic lipase) were associated with significantly different serum concentrations of BA and C4. Plasma concentrations of conjugated and secondary BAs differed between heterozygous carriers of SCARB1 (scavenger receptor class B1) mutations and unaffected individuals (P<0.05), but this difference was not significant after correction for multiple testing. Moreover, no differences in the lipoprotein distribution of BAs in the LPDS and HDL fractions from SCARB1 heterozygotes were observed. In conclusion, despite significant recoveries of BAs and C4 in HDL and despite the metabolic relationships between RCT and BA formation, monogenic disorders of HDL metabolism do not lead to altered serum concentrations of BAs and C4.

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Metabolic and genetic determinants of HDL metabolism and hepatic lipase activity in normolipidemic females

The Journal of Lipid Research ◽

10.1016/s0022-2275(20)33483-0 ◽

1999 ◽

Vol 40 (7) ◽

pp. 1211-1221 ◽

Cited By ~ 5

Author(s):

Elizabeth R. De Oliveira e Silva ◽

Margaret Kong ◽

Zhihua Han ◽

Catherine Starr ◽

Elizabeth M. Kass ◽

...

Keyword(s):

Lipase Activity ◽

Hepatic Lipase ◽

Genetic Determinants ◽

Hepatic Lipase Activity ◽

Hdl Metabolism

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CETP IN RARE DYSLIPIDEMIAS

Clinical & Investigative Medicine ◽

10.25011/cim.v32i6s.11136 ◽

2009 ◽

Vol 32 (6S) ◽

pp. 3

Author(s):

A Al-Sarraf ◽

K Sachs-Barrable ◽

J Hill ◽

K Wasan ◽

J Frohlich

Keyword(s):

New York ◽

Neutral Lipid ◽

Hepatic Lipase ◽

Rare Disorders ◽

Fluorescent Substrate ◽

Laboratory Findings ◽

Transfer Rates ◽

Donor And Acceptor ◽

Lcat Deficiency ◽

Hdl Metabolism

Objective: To determines CETP mass and activity in rare disorders of HDL metabolism. Methods: Patients: Fasting plasma samples were obtained from two individuals with TD and from patients with LCAT deficiency, analphalipoproteinemia, Hepatic lipase deficiency (HL), vasculitis, and hypoalphalipoprteinemia. Their clinical and laboratory findings have been previously reported. Assay: CETP activity was measured using commercial CETP Fluorescence kit (Roar Biomedical Inc., New York, NY). The kit includes donor (without apoA-I) and acceptor lipoprotein particles. Incubation of donor and acceptor with a CETP source results in the CETP mediated transfer of fluorescent neutral lipid from donor to acceptor, rate of which is determined by the increase in fluorescence intensity as the fluorescent neutral lipid is removed from the donor to the acceptor. The amount of fluorescent substrate transferred was expressed as pmoles of fluorescent substrate transferred within 3 hours. CETP concentration was measured by ELISA using specific rabbit antibody against human CETP. Results: While CETP mass correlated with serum HDL-C levels, the activity decreased in patients with LCAT deficiency, FED, HL deficiency and vascultis, but increased in TD. We speculate that the composition of HDL particles in these disorders differs and results in the different CE transfer rates. Conclusion: CETP mass correlates with the HDL-C concentration but the activity differ widely among the patients with rare disorders of HDL metabolism, probably due to the changes in HDL quality.

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