Year-end Sale % OFF 
Abstract
BackgroundThe proprotein convertase subtilisin/kexin type 9 (PCSK9) is an important factor in the etiology of familial hypercholesterolemia (FH) and is also an attractive therapeutic target to reduce low density lipoprotein (LDL) cholesterol. PCSK9 accelerates the degradation of hepatic low density lipoprotein receptor (LDLR) and low levels of hepatic PCSK9 activity are associated with reduced levels of circulating LDL-cholesterol.Methodology/Principal FindingsThe present study presents the first evidence for the efficacy of a locked nucleic acid (LNA) antisense oligonucleotide (LNA ASO) that targets both human and mouse PCSK9. We employed human hepatocytes derived cell lines HepG2 and HuH7 and a pancreatic mouse β-TC3 cell line known to express high endogenous levels of PCSK9. LNA ASO efficiently reduced the mRNA and protein levels of PCSK9 with a concomitant increase in LDLR protein levels after transfection in these cells. In vivo efficacy of LNA ASO was further investigated in mice by tail vein intravenous administration of LNA ASO in saline solution. The level of PCSK9 mRNA was reduced by ∼60%, an effect lasting more than 16 days. Hepatic LDLR protein levels were significantly up-regulated by 2.5–3 folds for at least 8 days and ∼2 fold for 16 days. Finally, measurement of liver alanine aminotransferase (ALT) levels revealed that long term LNA ASO treatment (7 weeks) does not cause hepatotoxicity.Conclusion/SignificanceLNA-mediated PCSK9 mRNA inhibition displayed potent reduction of PCSK9 in cell lines and mouse liver. Our data clearly revealed the efficacy and safety of LNA ASO in reducing PCSK9 levels, an approach that is now ready for testing in primates. The major significance and take home message of this work is the development of a novel and promising approach for human therapeutic intervention of the PCSK9 pathway and hence for reducing some of the cardiovascular risk factors associated with the metabolic syndrome.
Highlights
In 2003, the proprotein convertase subtilisin/kexin-9 (PCSK9; a 692 amino acid protein) was discovered [1] and its high expression levels in liver and small intestine and the chromosomal localization of its gene (,22 kb proprotein convertase subtilisin/kexin type 9 (PCSK9)) on 1p32.3, suggested a possible relationship to cholesterol metabolism [1]
These findings support the hypothesis that higher levels and/or activity of plasma PCSK9 increase the levels of circulating low density lipoprotein (LDL)-C and total cholesterol (TC), suggesting that long-term lowering of PCSK9 might be beneficial in reducing the incidence of coronary artery disease (CAD), and PCSK9 is an attractive target for treatment of dyslipidemia [22,23,24]
We present the first evidence for the efficacy of a short locked nucleic acid (LNA) antisense oligonucleotide (ASO) that targets both human and mouse PCSK9
Summary
In 2003, the proprotein convertase subtilisin/kexin-9 (PCSK9; a 692 amino acid protein) was discovered [1] and its high expression levels in liver and small intestine and the chromosomal localization of its gene (,22 kb PCSK9) on 1p32.3, suggested a possible relationship to cholesterol metabolism [1]. More than 60% reduction in PCSK9 mRNA levels in human HepG2 (panel A; P,0.01), and approximately 50% in HuH7 (panel B; P,0.02) and mouse bTC3 (panel C; P,0.05) cells were achieved after 24 h using either 10 or 25 nM LNA ASO.
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
