Effects of Recombinant Human Lecithin Cholesterol Acyltransferase on Lipoprotein Metabolism in Humans.
Arterioscler Thromb Vasc Biol 2024;
44:1407-1418. [PMID:
38695168 DOI:
10.1161/atvbaha.123.320387]
[Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2023] [Accepted: 03/28/2024] [Indexed: 05/24/2024]
Abstract
BACKGROUND
LCAT (lecithin cholesterol acyl transferase) catalyzes the conversion of unesterified, or free cholesterol, to cholesteryl ester, which moves from the surface of HDL (high-density lipoprotein) into the neutral lipid core. As this iterative process continues, nascent lipid-poor HDL is converted to a series of larger, spherical cholesteryl ester-enriched HDL particles that can be cleared by the liver in a process that has been termed reverse cholesterol transport.
METHODS
We conducted a randomized, placebocontrolled, crossover study in 5 volunteers with atherosclerotic cardiovascular disease, to examine the effects of an acute increase of recombinant human (rh) LCAT via intravenous administration (300-mg loading dose followed by 150 mg at 48 hours) on the in vivo metabolism of HDL APO (apolipoprotein)A1 and APOA2, and the APOB100-lipoproteins, very low density, intermediate density, and low-density lipoproteins.
RESULTS
As expected, recombinant human LCAT treatment significantly increased HDL-cholesterol (34.9 mg/dL; P≤0.001), and this was mostly due to the increase in cholesteryl ester content (33.0 mg/dL; P=0.014). This change did not affect the fractional clearance or production rates of HDL-APOA1 and HDL-APOA2. There were also no significant changes in the metabolism of APOB100-lipoproteins.
CONCLUSIONS
Our results suggest that an acute increase in LCAT activity drives greater flux of cholesteryl ester through the reverse cholesterol transport pathway without significantly altering the clearance and production of the main HDL proteins and without affecting the metabolism of APOB100-lipoproteins. Long-term elevations of LCAT might, therefore, have beneficial effects on total body cholesterol balance and atherogenesis.
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