Effect of Recombinant Human Lecithin Cholesterol Acyltransferase Infusion on Lipoprotein Metabolism in Mice

Pulmonary and Vascular Medicine Branch, Lipoprotein Metabolism Section, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD 20892, USA.
Journal of Pharmacology and Experimental Therapeutics (Impact Factor: 3.97). 10/2010; 335(1):140-8. DOI: 10.1124/jpet.110.169540
Source: PubMed


Lecithin cholesterol acyl transferase (LCAT) deficiency is associated with low high-density lipoprotein (HDL) and the presence of an abnormal lipoprotein called lipoprotein X (Lp-X) that contributes to end-stage renal disease. We examined the possibility of using LCAT an as enzyme replacement therapy agent by testing the infusion of human recombinant (r)LCAT into several mouse models of LCAT deficiency. Infusion of plasma from human LCAT transgenic mice into LCAT-knockout (KO) mice rapidly increased HDL-cholesterol (C) and lowered cholesterol in fractions containing very-low-density lipoprotein (VLDL) and Lp-X. rLCAT was produced in a stably transfected human embryonic kidney 293f cell line and purified to homogeneity, with a specific activity of 1850 nmol/mg/h. Infusion of rLCAT intravenously, subcutaneously, or intramuscularly into human apoA-I transgenic mice showed a nearly identical effect in increasing HDL-C approximately 2-fold. When rLCAT was intravenously injected into LCAT-KO mice, it showed a similar effect as plasma from human LCAT transgenic mice in correcting the abnormal lipoprotein profile, but it had a considerably shorter half-life of approximately 1.23 ± 0.63 versus 8.29 ± 1.82 h for the plasma infusion. rLCAT intravenously injected in LCAT-KO mice crossed with human apolipoprotein (apo)A-I transgenic mice had a half-life of 7.39 ± 2.1 h and increased HDL-C more than 8-fold. rLCAT treatment of LCAT-KO mice was found to increase cholesterol efflux to HDL isolated from mice when added to cells transfected with either ATP-binding cassette (ABC) transporter A1 or ABCG1. In summary, rLCAT treatment rapidly restored the normal lipoprotein phenotype in LCAT-KO mice and increased cholesterol efflux, suggesting the possibility of using rLCAT as an enzyme replacement therapy agent for LCAT deficiency.

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Available from: Xavier Rousset, Jul 03, 2015
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    • "Improving HDL functionality instead of simply increasing HDL-C levels might be much more important. Many HDL-C-based interventions, such as apoA-I-based compounds [41], apoA-I upregulators [42], ABCtransporter up-regulators, including microRNA-mediated therapeutics [43] [44], synthetic liver X receptor agonists [45] and lectincholesterol acyltransferase-based therapy [46], are under development and are still holding great promise for the future. "
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    • "Early successful attempts to correct the biochemical LCAT deficient phenotype through the infusion of normal plasma [9] provide the basis for the development of enzyme replacement therapy as a therapeutic strategy for LCAT deficiency, particularly because of its relatively long half-life, and the fact that LCAT acts in the plasma compartment and does not need to be delivered to a specific tissue or cellular compartment. Indeed, a recombinant LCAT proved to rapidly restore the normal lipoprotein phenotype in LCAT deficient mice [10], and it is presently under clinical development [11]. "
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