title: Hypercholesterolemia Induced by a PCSK9 Gain-of-Function Mutation Augments Angiotensin II-Induced Abdominal Aortic Aneurysms in C57BL/6 Mice-Brief Report.
abstract: Gain-of-function mutations of PCSK9 (proprotein convertase subtilisin/kexin type 9) lead to hypercholesterolemia. This study was to determine whether infection of normocholesterolemic mice with an adeno-associated viral (AAV) vector expressing a gain-of-function mutation of mouse PCSK9 increased angiotensin II (AngII)-induced abdominal aortic aneurysms.
  
  
  
  In an initial study, male C57BL/6 mice were injected intraperitoneally with either an empty vector or PCSK9 gain-of-function mutation (D377Y). AAV at 3 doses and fed a saturated fat-enriched diet for 6 weeks. Two weeks after AAV injection, mice were infused with AngII for 4 weeks. Plasma PCSK9 concentrations were increased dose dependently in mice injected with AAV containing PCSK9D377Y mutation and positively associated with elevations of plasma cholesterol concentrations. Infection with intermediate and high doses of PCSK9D377Y.AAV led to equivalent increases of maximal width of abdominal aortas in C57BL/6 mice infused with AngII. Therefore, the intermediate dose was used in subsequent experiments. We then determined effects of PCSK9D377Y.AAV infection on 5 normolipidemic mouse strains, demonstrating that C57BL/6 mice were the most susceptible to this AAV infection. PCSK9D377Y.AAV infected male C57BL/6 mice were also compared with age-matched male low-density lipoprotein receptor(-/-) mice. Although plasma cholesterol concentrations were lower in mice infected with PCSK9D377Y.AAV, these mice had equivalent abdominal aortic aneurysmal formation, compared to low-density lipoprotein receptor(-/-) mice. In a separate study, reduced plasma PCSK9 concentrations by PCSK9 antisense oligonucleotides in male low-density lipoprotein receptor(-/-) mice did not influence AngII-induced abdominal aortic aneurysms.
  
  
  
  AAV-mediated infection with a mouse PCSK9 gain-of-function mutation is a rapid, easy, and efficient approach for inducing hypercholesterolemia and promoting abdominal aortic aneurysms in C57BL/6 mice infused with AngII.
authors.affiliation: From the Department of Physiology (H.L., A.D.), Saha Cardiovascular Research Center (H.L., D.A.H., A.B., A.D.), University of Kentucky, Lexington; and Antisense Drug Discovery, Ionis Pharmaceuticals, Inc., Carlsbad, CA (M.J.G., A.E.M.). Hong.Lu@uky.edu Alan.Daugherty@uky.edu.
authors.forename: Hong
authors.initials: H
authors.lastname: Lu
authors.affiliation: From the Department of Physiology (H.L., A.D.), Saha Cardiovascular Research Center (H.L., D.A.H., A.B., A.D.), University of Kentucky, Lexington; and Antisense Drug Discovery, Ionis Pharmaceuticals, Inc., Carlsbad, CA (M.J.G., A.E.M.).
authors.forename: Deborah A
authors.initials: DA
authors.lastname: Howatt
authors.affiliation: From the Department of Physiology (H.L., A.D.), Saha Cardiovascular Research Center (H.L., D.A.H., A.B., A.D.), University of Kentucky, Lexington; and Antisense Drug Discovery, Ionis Pharmaceuticals, Inc., Carlsbad, CA (M.J.G., A.E.M.).
authors.forename: Anju
authors.initials: A
authors.lastname: Balakrishnan
authors.affiliation: From the Department of Physiology (H.L., A.D.), Saha Cardiovascular Research Center (H.L., D.A.H., A.B., A.D.), University of Kentucky, Lexington; and Antisense Drug Discovery, Ionis Pharmaceuticals, Inc., Carlsbad, CA (M.J.G., A.E.M.).
authors.forename: Mark J
authors.initials: MJ
authors.lastname: Graham
authors.affiliation: From the Department of Physiology (H.L., A.D.), Saha Cardiovascular Research Center (H.L., D.A.H., A.B., A.D.), University of Kentucky, Lexington; and Antisense Drug Discovery, Ionis Pharmaceuticals, Inc., Carlsbad, CA (M.J.G., A.E.M.).
authors.forename: Adam E
authors.initials: AE
authors.lastname: Mullick
authors.affiliation: From the Department of Physiology (H.L., A.D.), Saha Cardiovascular Research Center (H.L., D.A.H., A.B., A.D.), University of Kentucky, Lexington; and Antisense Drug Discovery, Ionis Pharmaceuticals, Inc., Carlsbad, CA (M.J.G., A.E.M.). Hong.Lu@uky.edu Alan.Daugherty@uky.edu.
authors.forename: Alan
authors.initials: A
authors.lastname: Daugherty
mesh_terms: D000804:Angiotensin II; D000818:Animals; D017544:Aortic Aneurysm, Abdominal / Q000097:blood / Q000139:chemically induced* / Q000201:enzymology / Q000235:genetics; D015415:Biomarkers / Q000097:blood; D002784:Cholesterol / Q000097:blood; D000229:Dependovirus / Q000235:genetics; D004195:Disease Models, Animal; D018014:Gene Transfer Techniques; D020022:Genetic Predisposition to Disease; D005822:Genetic Vectors; D006937:Hypercholesterolemia / Q000097:blood / Q000150:complications / Q000201:enzymology / Q000235:genetics*; D008297:Male; D057507:Mice, 129 Strain; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D008811:Mice, Inbred DBA; D018345:Mice, Knockout; D009154:Mutation; D016376:Oligonucleotides, Antisense / Q000235:genetics / Q000378:metabolism; D000071449:Proprotein Convertase 9 / Q000097:blood / Q000235:genetics*; D011973:Receptors, LDL / Q000172:deficiency / Q000235:genetics; D013045:Species Specificity; D013997:Time Factors
chemical_list: D015415:Biomarkers; D016376:Oligonucleotides, Antisense; D011973:Receptors, LDL; D000804:Angiotensin II; D002784:Cholesterol; C472126:Pcsk9 protein, mouse; D000071449:Proprotein Convertase 9
keywords: Pcsk9 protein, mouse; aortic aneurysms; atherosclerosis; hypercholesterolemia; low-density lipoprotein