• We are sorry, but NCBI web applications do not support your browser and may not function properly. More information
Logo of nihpaAbout Author manuscriptsSubmit a manuscriptNIH Public Access; Author Manuscript; Accepted for publication in peer reviewed journal;
Arterioscler Thromb Vasc Biol. Author manuscript; available in PMC Nov 29, 2009.
Published in final edited form as:
PMCID: PMC2784896
NIHMSID: NIHMS126292

Athsq1 is an atherosclerosis modifier locus with dramatic effects on lesion area and prominent accumulation of versican

Abstract

Objective

Susceptibility to atherosclerosis is genetically complex and modifier genes that do not operate via traditional risk factors are largely unknown. A mouse genetics approach can simplify the genetic analysis as well as provide tools for mechanistic studies.

Methods and Results

We previously identified Atherosclerosis susceptibility QTL (Athsq1) on chromosome 4 acting independently of systemic risk factors. We now report confirmation of this locus in congenic strains carrying the MOLF-derived susceptibility allele in the C57BL/6J-Ldlr-/- genetic background. Homozygous congenic mice exhibited 4.5-fold greater lesion area compared to non-congenic littermates (p < 0.0001). Analysis of extracellular matrix composition revealed prominent accumulation of versican, a presumed proatherogenic matrix component abundant in human lesions but almost absent in the widely-used C57BL/6 murine atherosclerosis model. The results of a bone marrow transplantation experiment suggested that both the accelerated lesion development and versican accumulation are mediated, at least in part, by macrophages. Interestingly, comparative mapping revealed that the Athsq1 congenic interval contains the mouse region homologous to a widely-replicated CHD locus on human chromosome 9p21.

Conclusion

These studies confirm the proatherogenic activity of a novel gene(s) in the MOLF-derived Athsq1 locus and provide in vivo evidence for a causative role of versican in lesion development.

Keywords: atherosclerosis, congenic strain, genetics, extracellular, matrix, quantitative trait locus

Susceptibility to atherosclerosis is influenced by both genetic and environmental factors, with approximately 40-60% of inter-individual variation attributed to genetic factors.1 The complex etiology has hampered genetic studies of atherosclerosis in humans per se but some important recent advances have been made, especially for genome-wide single nucleotide polymorphism (SNP) association studies. Early studies utilized the candidate gene approach to identify rare genetic variants contributing to traditional risk factors including plasma levels of LDL/VLDL, HDL, lipoprotein (a), and homocysteine as well as measures of coagulation and blood pressure.2-5 Importantly, many of these genes have recently been shown to contribute to population variation using large-scale genome-wide SNP association studies.6-8 Attempts to identify genes directly underlying coronary artery disease (CAD)/myocardial infarct (MI) have been pursued through linkage studies of families enriched for disease9-13 and large-scale association studies.14-17 While these studies have suggested a number of candidate loci, including the identification of several pro-inflammatory genes, most still require replication. Most recently, whole-genome SNP association studies have revealed a common variant on chromosome (chr) 9p21 for CHD.18-21 The novel CHD locus on chr 9 resides in an apparent gene desert and the underlying gene and mechanism of action are unknown. However, the locus is the first to be widely-replicated for CHD. Thus, while a number of genes contributing to traditional risk factors have been identified, few of the genes underlying non-traditional risk factors are known.

Animal models, especially mice and rats, offer an alternative approach for the genetic analysis of complex diseases such as atherosclerosis. In early work, the existence of atherosclerosis susceptibility loci in the mouse model was suggested using recombinant inbred strains of mice.22-25 More recently, the chromosomal locations of such loci have been mapped using linkage analysis of experimental crosses.26-30 With the exception of a locus on distal chr 1, these loci exert their effects independent of traditional risk factors including plasma cholesterol and triglyceride levels, fasting plasma insulin levels and body weight. We previously mapped a locus affecting atherosclerotic lesion area in a cross between strains MOLF/Ei (MOLF) and C57BL/6J(B6)-Ldlr-/-.27 Atherosclerosis susceptibility QTL 1 (Athsq1) was identified on chr 4 with susceptibility derived from the MOLF strain. The effect of Athsq1 was independent of systemic risk factors, suggesting a local effect within the vessel wall. We now report confirmation of Athsq1 in congenic strains, with prominent accumulations of versican, a major extracellular matrix proteoglycan component of human lesions not previously observed in mouse lesions. We also show that both the accelerated atherogenesis and versican accumulation are mediated, at least in part, by bone marrow (BM)-derived cells.

Methods

Mice

MOLF/Ei (MOLF) and B6.129S7-Ldlrtm1Her (B6-Ldlr-/-) were purchased from The Jackson Laboratory (Bar Harbor, ME). B6.MOLF-Athsq1 congenic mice were generated by introgression of the MOLF donor interval into the B6-Ldlr-/- background using a marker-assisted method.31 In total, 100 microsatellite markers were used for congenic interval and background screening. N7 generation mice were weaned onto standard laboratory chow (PicoLab Rodent 20, #5053) at 21 days of age and switched to a Western-type diet (WTD) containing 21% butterfat and 0.15% cholesterol (Harlan Teklad Adjusted Calories TD 88137, Madison, WI) at 8-12 weeks (wks) of age. Mice were sacrificed after six or 12 wks of WTD feeding as indicated. The breeding colony was produced and maintained in a specific pathogen-free facility. All mice were given ad libitum access to food and water and maintained on a standard 12-h light-dark cycle. All procedures were in accordance with institutional guidelines.

DNA Extraction and Ldlr Genotyping

DNA was extracted from tail tips and microsatellite markers and Ldlr alleles were typed by PCR as previously described.27

Atherosclerotic Lesion Measurements

Serial sections were prepared from the aortic root as previously described.(REFs) Every tenth section, for a total of six sections per mouse, was stained with hematoxylin and eosin (H&E) and lesion area quantified by video microscopy. Average lesion size was determined from 5-6 sections per mouse. Necrotic core area was determined from H&E stained sections as the acellular area beneath the fibrous cap. Cap thickness was determined from Verhoeff's stained sections using a scoring system based on numbers of elastic layers as described previously.32 Collagen was detected with Masson's trichrome stain (Poly Scientific), hyaluronan with biotinylated hyaluronan binding protein (Tom –source?), and total proteoglycans with Movatts stain. Frozen sections were used for all 12-wk WTD data and paraffin sections for 6-wk data.

Immunohistochemistry

Sections were immunostained for versican using a a rabbit polyclonal antibody against the β-gag domain of mouse versican, at 7 μg/ml (Chemicon International, Temecula, CA). Color was developed using a biotinylated secondary antibody, the Vectastain Elite ABC kit (Vector Laboratories, Burlingame, CA), and DAB or the NovaRed peroxidase substrate (Vector Laborartories, Burlingame, CA). Nuclei were counterstained with methyl green (DAB) or Gills #3 hematoxylin (NovaRed). Omission of the primary antibody or use of an irrelevant rabbit IgG antibody served as negative control.

Protein and mRNA Quantification of Versican

Expanded methods are available in the online data supplement. Briefly, proximal aortas were collected from 6-wk WTD-fed mice, cleared of adipose tissue and flash-frozen. Proteoglycans were isolated from protein extracts by DEAE Sephacel chromatography and digested with chondroitin ABC lyase.33 Digestion products were analyzed by SDS-Page followed by Western blotting with anti-mouse β-gag antibody. Relative abundance of versican was determined by quantitative image analysis.34-36 cDNA synthesis from total RNA was carried out using standard procedures. Real-time PCR was performed using Taqman Gene Expression Assay Mm_00490179_ml for mouse versican (detects all splice variants) with an ABI 7900 HT instrument. Assays were performed in triplicate and normalized to endogenous eukaryotic 18s (Taqman Gene Expression Assay Hs_99999901_sl).

BM Transplantation

BM transplantation was performed as described.37 Irradiated B6-Ldlr-/- mice were injected with BM derived from either congenic (carrying the MOLF interval from D4Mit185-D4Mit70) or non-congenic mice. Reconstitution of the BM with donor cells was checked at 6-wks post-injection using the UltraClean DNA BloodSpin kit (MO BIO Laboratories, Carlsbad, CA) and genotyping at D4Mit185. Mice were then fed the WTD for 11 wks, sacrificed, and aortic root dissected as above.

Statistical Analysis

ANOVA or Mann Whitney (if unequal variance) was performed using STATVIEW 5.0 (Abacus Concepts, Inc.). Data are mean ± SEM.

The authors had full access to the data and take responsibility for its integrity. All authors have read and agree to the manuscript as written,

Results

B6.MOLF-Athsq1 congenic mice exhibit accelerated lesion development

To confirm the Athsq1 susceptibility locus and test its amenability to fine mapping, we created congenic mice carrying one or two copies of the MOLF-derived susceptibility allele from chr 4 on a B6-Ldlr-/- background. The full congenic interval extended from D4Mit185 (43 cM) to D4Mit42 (81 cM) (Figure 1A). However, homozygous mice carrying the full interval exhibited a high rate of mortality shortly after weaning. Mice carrying a shorter interval, extending from D4Mit185 (43 cM) to D4Mit70 (62 cM) (Figure 1A), developed normally in the homozygous state. After 12-wks of WTD feeding, mean atherosclerotic lesion area was significantly greater in Athsq1 heterozygotes (b/m) and Athsq1 homozygotes carrying the full interval (m/m) or the shorter interval (m*/m*) compared to non-congenic littermates (b/b). Homozygous mice were thus maintained as m*/m* (carrying the shorter interval) for the remaining experiments. The effect of Athsq1 on lesion area was more dramatic at the 6-wk timepoint when b/m heterozygotes exhibited almost 2-fold and m*/m* homozygotes greater than 4-fold greater lesion area compared to non-congenic b/b controls. The lesion area values at the 6-wk timepoint were 93,000 ± 9,000 μm2/section, mean ± SEM (b/m), 220,000 ± 35,000 μm2/section (m*/m*), and 53,000 ± 5,000 μm2/section (b/b); p<0.0003 and p<0.0001, respectively) (Figure 1B). The differences in lesion area were independent of plasma cholesterol levels (data not shown).

Figure 1
Increased atherosclerotic lesion area in Athsq1 congenic mice. A, Genetic map of mouse chr 4 and genotypes (B6, black; MOLF, white) of congenic (b/m, m/m, m*/m*) and non-congenic (b/b) strains across the Athsq1 region. B, Mean lesion areas following 12- ...

Detailed analysis of lesion composition revealed dramatic differences comparing congenic and non-congenic mice. While non-congenic littermate controls exhibited small, focal, fatty streak lesions (Figure 1A, D, G and J), Athsq1 b/m heterozygotes developed both fatty streak lesions and more advanced fatty-fibrous lesions characterized by fibrous cap and necrotic core formation (Figure 1B, E, H and K). In stark contrast to Athsq1 b/b controls, Athsq1 m*/m* homozygotes exhibited advanced fibrous lesions, often covering the entire circumference of the vessel wall (Figure 1C, F, I and L). The most advanced lesions from control mice exhibited thin (single elastic layer) fibrous caps while advanced lesions from Athsq1 b/m and Athsq1 m*/m* mice exhibited intermediate (two to four elastic layers) or thick (greater than four elastic layers) fibrous caps (p<0.0002 for homozygotes versus controls) 32. Mean necrotic core area, defined as the acellular area encapsulated by the cellular regions of the cap and shoulders, was significantly greater in congenic mice (10,000 ± 4,000 μm2/section for Athsq1 b/m and 32,000 ± 11,000 μm2/section for Athsq1 m*/m*) compared to non-congenic controls (300 ± 1200 μm2/section; p<0.04 and p<0.0006, respectively). Thus, the congenic mice exhibited greatly accelerated atherosclerotic lesion development in a gene dosage-dependent manner.

Atherosclerotic lesions of Athsq1 congenic mice exhibit prominent accumulation of the proatherogenic matrix component, versican

Atherogenesis is initiated by lipoprotein retention and modification, extracellular matrix deposition, and inflammatory cell recruitment. To gain insight into the mechanism of accelerated atherogenesis in Athsq1 congenic mice, we examined extracellular matrix composition of atherosclerotic lesions using a variety of special stains and antibodies. Staining for collagen, elastin, and hyaluronan showed no differences in comparable lesions derived from Athsq1 m*/m* congenic and Athsq1 b/b non-congenic mice (data not shown). We also stained for versican using a polyclonal antibody specific for the intact core protein. Immunostaining revealed dramatic accumulations of versican in lesions derived from congenic mice but not controls (Figure 3A-D). Staining was most prominent at the medial area just beneath the plaques and extending into the media. Staining was also observed in the cellular regions of the intima in congenic mice but rarely in non-congenics. These findings were confirmed by morphometric analysis of the immunostained regions (Figure 3E). In 6-wk WTD-fed mice, the mean versican-positive medial area was more than 10-fold greater in Athsq1 m*/m* mice compared to Athsq1 b/b controls (p < 0.0001). Mean intimal lesion staining covered 21% of the total lesion area in congenics compared to 4% in controls (p = 0.0008). Similar results were observed in 12-wk WTD-fed mice (Figure 3E).

Figure 3
Increased abundance of versican in Athsq1 congenic atherosclerotic plaques. A-D, Immunostaining for versican (brown) in the aortic root of B6-Ldlr-/- (b/b) and congenic (m*/m*) mice. M, media; Pl, plaque. 400× magnification. E, Quantification ...

To confirm the immunohistochemistry data, we performed biochemical analysis of versican in lesion extracts using the same polyclonal antibody specific for the intact core protein. Indeed, a 2.5-fold increase in versican protein level was observed in extracts from Athsq1 m*/m* congenics compared to Athsq1 b/b controls after 6-wk WTD feeding (Figure 4A, B). Using a probe-based quantitative PCR assay, we observed no difference in versican mRNA levels between the strains (Figure 4C). These data suggest a post-transcriptional mechanism regulating accumulation of versican.

Figure 4
Versican protein and mRNA levels in aortic homogenates from Athsq1 congenic (m*/m*) and non-congenic (b/b) mice. A, Immunoblot using an antibody against versican intact core protein. B, Quantification by densitometry. C, Relative abundance of mRNA measured ...

Accelerated atherosclerosis and versican accumulation in Athsq1 congenic mice is mediated, at least in part, by bone marrow-derived cells

To determine the role of macrophages in Athsq1-mediated atherogenesis, we performed a BM transplantation experiment. Lethally-irradiated B6-Ldlr-/- recipient mice were injected with donor BM derived from congenic or non-congenic mice (both on the B6-Ldlr-/- background). The mice were fed WTD for eleven weeks following recovery/repopulation of the BM-derived cells with donor cells, Lesion area was significantly increased in mice receiving BM derived from Athsq1 m*/m* congenic mice compared to mice receiving BM from non-congenic b/b controls (p = 0.0016) (Figure 5A). There was also greater accumulation of versican in mice receiving congenic-derived BM (Fig 5B, C): a 2.5-fold increase in versican-positive medial area (Figure 5D) and 6/15 mice were positive for intimal staining (1-5% of lesion area) compared to none of the mice receiving control bone marrow. These results suggest that BM-derived cells play an important role in development of the lesion susceptibility phenotype, including versican accumulation in lesions. However, the fold difference in lesion area (1.6-fold) was not as great as in the congenic strain comparison (4-fold) and the overall abundance of versican was less. Thus, it is likely that vascular cells also contribute to lesion development in this model.

Figure 5
Increased lesion area and versican accumulation in B6-Ldlr-/- mice transplanted with Athsq1 congenic (m*/m*) BM compared to non-congenic (b/b) BM. A, Quantification of lesion area by morphometric analysis. Horizontal bars represent group means. B,C Immunostaining ...

Discussion

We have confirmed the atherosclerosis susceptibility QTL, Athsq1 on mouse chr 4, in a congenic strain. Homozygous congenic mice have a dramatic phenotype with 4.5-fold greater lesion area and prominent accumulation of aortic versican compared to controls. Mechanistic and morphological studies in human lesions have suggested a pro-atherogenic role for versican. The association of prominent versican accumulation with accelerated atherogenesis in the congenic strains provides in vivo evidence supporting a causal relationship between versican accumulation and atherogenesis. Our findings suggest that the MOLF-derived gene(s) underlying Athsq1 acts to post-transcriptionally regulate versican accumulation during lesion development.

Although prominent in human atherosclerotic lesions, versican does not appear to be a major matrix component in mouse models of atherosclerosis in the C57BL/6J background.38 Using immunohistochemistry, Kunjathoor and colleagues reported little to no accumulation of versican in early, intermediate, and advanced lesions of both B6-Ldlr-/- and B6-Apoe-/- mice.38 Our study is in good agreement with this earlier work as lesions derived from non-congenic B6-Ldlr-/- mice had very little versican accumulation (Figures 3 and and4).4). Thus, the prominent accumulation of aortic versican observed in Athsq1 congenic strains was surprising and suggests a causative role in determining disease susceptibility in the Athsq1 congenic mouse model.

Versican has been indirectly implicated in the pathogenesis of vascular diseases, including atherosclerosis and restenosis.39 In atherosclerosis, versican is prominent in the ECM of both early intimal thickenings as well as advanced lesions. It is also prominent in restenotic lesions following angioplasty.40 Versican binds LDL particles with high affinity41 and it has been speculated that accumulation of versican in the vessel wall may promote both extracellular lipoprotein retention as well as intracellular uptake leading to foam cell formation.39 Versican also binds hyaluronan, forming expanded viscoelastic matrices required for SMC proliferation and migration in cell culture.42 Migration of SMCs from the media into the intima occurs early in atherogenesis and promotes lesion progression. Versican-hyaluronan structures also promote mononuclear leukocyte aggregation and adhesion43, 44 via interaction with leukocyte cell surface receptors including CD44,45 and L- and P-selectins.46 Interestingly, versican accumulation in lesions from Athsq1 congenic mice was prominent in the medial area just beneath the plaques and was also observed in the cellular regions of the plaques. Thus, accumulation of versican may provide a local niche for rapid expansion of atherosclerotic plaques via multiple mechanisms.

The original linkage peak for Athsq1 was located distal to the recombination breakpoint of the shorter m*/m* congenic interval. However, the distal end of the m*/m* interval (between 62.3 cM and 66 cM) does fall within the 2-LOD-unit confidence interval for the QTL (57-97 cM). It is possible that the original QTL was detected due to atherogenic effects of more than one gene (perhaps one located closer to the peak and one more proximally). However, the phenotype of the homozygous full m/m congenics was similar to that of the shorter m*/m* congenics, suggesting that the main gene(s) are located within the m*/m* interval. This shorter interval is still relatively large in terms of numbers of genes and any discussion about possible candidate genes would be highly speculative. However, it is interesting to note that comparative mapping of mouse and human chromosomes revealed that the m*/m* congenic interval contains the mouse homologous region to the human CHD locus on 9p21. Two flanking markers for the human locus include Cdkn2a (at 89.1 Mb) and Dmrta1 (at 89.5 Mb); the m*/m* congenic interval covers 82.2 –134.2 Mb. An interesting question is whether the MOLF strain utilized in our study carries a variant of the gene underlying the human 9p locus and whether this contributes to the pro-atherogenic phenotype. Further studies, including fine-mapping of the congenic interval, will be required to identify the gene(s) underlying the Athsq1 locus. However, this study illustrates the potential usefulness of the mouse genetics approach when used in conjunction with detailed lesion analysis in terms of defining the underlying pathophysiology.

Figure 2
Accelerated lesion development is accompanied by more complex lesions in Athsq1 congenic mice. Sections from B6-Ldlr-/- mice c(b/b) and congenic mice carrying one (b/m) or two (m*/m*) copies of a MOLF-derived interval (6-wk WTD). NC, necrotic core; arrow, ...

Acknowledgments

We thank Daniel Teupser for the processing and quantification of hearts from the first phase of this project. The technical assistance of Kadesha Collins-Fletcher is gratefully acknowledged.

Funding Sources

This work was supported by Program Project Grants HL 54591, HL 18645, HL_______ and Reynolds' Foundation Grant _________.

Footnotes

Disclosures

None.

References

1. Motulsky AGBJ. Genetics of coronary artery disease. In: King RARJ, Motulsky AG, editors. The Genetic Basis of Common Disease. New York, NY: Oxford University Press; 2002.
2. Lusis AJ, Mar R, Pajukanta P. Genetics of atherosclerosis. Annu Rev Genomics Hum Genet. 2004;5:189–218. [PubMed]
3. Abifadel M, Varret M, Rabes JP, Allard D, Ouguerram K, Devillers M, Cruaud C, Benjannet S, Wickham L, Erlich D, Derre A, Villeger L, Farnier M, Beucler I, Bruckert E, Chambaz J, Chanu B, Lecerf JM, Luc G, Moulin P, Weissenbach J, Prat A, Krempf M, Junien C, Seidah NG, Boileau C. Mutations in PCSK9 cause autosomal dominant hypercholesterolemia. Nat Genet. 2003;34:154–156. [PubMed]
4. Cohen J, Pertsemlidis A, Kotowski IK, Graham R, Garcia CK, Hobbs HH. Low LDL cholesterol in individuals of African descent resulting from frequent nonsense mutations in PCSK9. Nat Genet. 2005;37:161–165. [PubMed]
5. Cohen JC, Kiss RS, Pertsemlidis A, Marcel YL, McPherson R, Hobbs HH. Multiple rare alleles contribute to low plasma levels of HDL cholesterol. Science. 2004;305:869–872. [PubMed]
6. Willer CJ, Sanna S, Jackson AU, Scuteri A, Bonnycastle LL, Clarke R, Heath SC, Timpson NJ, Najjar SS, Stringham HM, Strait J, Duren WL, Maschio A, Busonero F, Mulas A, Albai G, Swift AJ, Morken MA, Narisu N, Bennett D, Parish S, Shen H, Galan P, Meneton P, Hercberg S, Zelenika D, Chen WM, Li Y, Scott LJ, Scheet PA, Sundvall J, Watanabe RM, Nagaraja R, Ebrahim S, Lawlor DA, Ben-Shlomo Y, Davey-Smith G, Shuldiner AR, Collins R, Bergman RN, Uda M, Tuomilehto J, Cao A, Collins FS, Lakatta E, Lathrop GM, Boehnke M, Schlessinger D, Mohlke KL, Abecasis GR. Newly identified loci that influence lipid concentrations and risk of coronary artery disease. Nat Genet. 2008;40:161–169. [PubMed]
7. Kathiresan S, Melander O, Guiducci C, Surti A, Burtt NP, Rieder MJ, Cooper GM, Roos C, Voight BF, Havulinna AS, Wahlstrand B, Hedner T, Corella D, Tai ES, Ordovas JM, Berglund G, Vartiainen E, Jousilahti P, Hedblad B, Taskinen MR, Newton-Cheh C, Salomaa V, Peltonen L, Groop L, Altshuler DM, Orho-Melander M. Six new loci associated with blood low-density lipoprotein cholesterol, high-density lipoprotein cholesterol or triglycerides in humans. Nat Genet. 2008;40:189–197. [PMC free article] [PubMed]
8. Kooner JS, Chambers JC, Aguilar-Salinas CA, Hinds DA, Hyde CL, Warnes GR, Gomez Perez FJ, Frazer KA, Elliott P, Scott J, Milos PM, Cox DR, Thompson JF. Genome-wide scan identifies variation in MLXIPL associated with plasma triglycerides. Nat Genet. 2008;40:149–151. [PubMed]
9. Broeckel U, Hengstenberg C, Mayer B, Holmer S, Martin LJ, Comuzzie AG, Blangero J, Nurnberg P, Reis A, Riegger GA, Jacob HJ, Schunkert H. A comprehensive linkage analysis for myocardial infarction and its related risk factors. Nat Genet. 2002;30:210–214. [PubMed]
10. Francke S, Manraj M, Lacquemant C, Lecoeur C, Lepretre F, Passa P, Hebe A, Corset L, Yan SL, Lahmidi S, Jankee S, Gunness TK, Ramjuttun US, Balgobin V, Dina C, Froguel P. A genome-wide scan for coronary heart disease suggests in Indo-Mauritians a susceptibility locus on chromosome 16p13 and replicates linkage with the metabolic syndrome on 3q27. Hum Mol Genet. 2001;10:2751–2765. [PubMed]
11. Pajukanta P, Cargill M, Viitanen L, Nuotio I, Kareinen A, Perola M, Terwilliger JD, Kempas E, Daly M, Lilja H, Rioux JD, Brettin T, Viikari JS, Ronnemaa T, Laakso M, Lander ES, Peltonen L. Two loci on chromosomes 2 and X for premature coronary heart disease identified in early- and late-settlement populations of Finland. Am J Hum Genet. 2000;67:1481–1493. [PMC free article] [PubMed]
12. Wang Q, Rao S, Shen GQ, Li L, Moliterno DJ, Newby LK, Rogers WJ, Cannata R, Zirzow E, Elston RC, Topol EJ. Premature myocardial infarction novel susceptibility locus on chromosome 1P34-36 identified by genomewide linkage analysis. Am J Hum Genet. 2004;74:262–271. [PMC free article] [PubMed]
13. Shen GQ, Li L, Girelli D, Seidelmann SB, Rao S, Fan C, Park JE, Xi Q, Li J, Hu Y, Olivieri O, Marchant K, Barnard J, Corrocher R, Elston R, Cassano J, Henderson S, Hazen SL, Plow EF, Topol EJ, Wang QK. An LRP8 variant is associated with familial and premature coronary artery disease and myocardial infarction. Am J Hum Genet. 2007;81:780–791. [PMC free article] [PubMed]
14. Ozaki K, Inoue K, Sato H, Iida A, Ohnishi Y, Sekine A, Odashiro K, Nobuyoshi M, Hori M, Nakamura Y, Tanaka T. Functional variation in LGALS2 confers risk of myocardial infarction and regulates lymphotoxin-alpha secretion in vitro. Nature. 2004;429:72–75. [PubMed]
15. Ozaki K, Ohnishi Y, Iida A, Sekine A, Yamada R, Tsunoda T, Sato H, Hori M, Nakamura Y, Tanaka T. Functional SNPs in the lymphotoxin-alpha gene that are associated with susceptibility to myocardial infarction. Nat Genet. 2002;32:650–654. [PubMed]
16. Helgadottir A, Manolescu A, Thorleifsson G, Gretarsdottir S, Jonsdottir H, Thorsteinsdottir U, Samani NJ, Gudmundsson G, Grant SF, Thorgeirsson G, Sveinbjornsdottir S, Valdimarsson EM, Matthiasson SE, Johannsson H, Gudmundsdottir O, Gurney ME, Sainz J, Thorhallsdottir M, Andresdottir M, Frigge ML, Topol EJ, Kong A, Gudnason V, Hakonarson H, Gulcher JR, Stefansson K. The gene encoding 5-lipoxygenase activating protein confers risk of myocardial infarction and stroke. Nat Genet. 2004;36:233–239. [PubMed]
17. McCarthy JJ, Parker A, Salem R, Moliterno DJ, Wang Q, Plow EF, Rao S, Shen G, Rogers WJ, Newby LK, Cannata R, Glatt K, Topol EJ. Large scale association analysis for identification of genes underlying premature coronary heart disease: cumulative perspective from analysis of 111 candidate genes. J Med Genet. 2004;41:334–341. [PMC free article] [PubMed]
18. Helgadottir A, Thorleifsson G, Manolescu A, Gretarsdottir S, Blondal T, Jonasdottir A, Jonasdottir A, Sigurdsson A, Baker A, Palsson A, Masson G, Gudbjartsson DF, Magnusson KP, Andersen K, Levey AI, Backman VM, Matthiasdottir S, Jonsdottir T, Palsson S, Einarsdottir H, Gunnarsdottir S, Gylfason A, Vaccarino V, Hooper WC, Reilly MP, Granger CB, Austin H, Rader DJ, Shah SH, Quyyumi AA, Gulcher JR, Thorgeirsson G, Thorsteinsdottir U, Kong A, Stefansson K. A common variant on chromosome 9p21 affects the risk of myocardial infarction. Science. 2007;316:1491–1493. [PubMed]
19. McPherson R, Pertsemlidis A, Kavaslar N, Stewart A, Roberts R, Cox DR, Hinds DA, Pennacchio LA, Tybjaerg-Hansen A, Folsom AR, Boerwinkle E, Hobbs HH, Cohen JC. A common allele on chromosome 9 associated with coronary heart disease. Science. 2007;316:1488–1491. [PMC free article] [PubMed]
20. Samani NJ, Erdmann J, Hall AS, Hengstenberg C, Mangino M, Mayer B, Dixon RJ, Meitinger T, Braund P, Wichmann HE, Barrett JH, Konig IR, Stevens SE, Szymczak S, Tregouet DA, Iles MM, Pahlke F, Pollard H, Lieb W, Cambien F, Fischer M, Ouwehand W, Blankenberg S, Balmforth AJ, Baessler A, Ball SG, Strom TM, Braenne I, Gieger C, Deloukas P, Tobin MD, Ziegler A, Thompson JR, Schunkert H. Genomewide association analysis of coronary artery disease. N Engl J Med. 2007;357:443–453. [PMC free article] [PubMed]
21. Larson MG, Atwood LD, Benjamin EJ, Cupples LA, D'Agostino RB, Sr, Fox CS, Govindaraju DR, Guo CY, Heard-Costa NL, Hwang SJ, Murabito JM, Newton-Cheh C, O'Donnell CJ, Seshadri S, Vasan RS, Wang TJ, Wolf PA, Levy D. Framingham Heart Study 100K project: genome-wide associations for cardiovascular disease outcomes. BMC Med Genet. 2007;8(Suppl 1):S5. [PMC free article] [PubMed]
22. Paigen B, Mitchell D, Reue K, Morrow A, Lusis AJ, Leboeuf RC. Ath-1, a Gene Determining Atherosclerosis Susceptibility and High-Density-Lipoprotein Levels in Mice. Proceedings of the National Academy of Sciences of the United States of America. 1987;84:3763–3767. [PMC free article] [PubMed]
23. Paigen B, Nesbitt MN, Mitchell D, Albee D, LeBoeuf RC. Ath-2, a second gene determining atherosclerosis susceptibility and high density lipoprotein levels in mice. Genetics. 1989;122:163–168. [PMC free article] [PubMed]
24. Paigen B, Ishida BY, Verstuyft J, Winters RB, Albee D. Atherosclerosis susceptibility differences among progenitors of recombinant inbred strains of mice. Arteriosclerosis. 1990;10:316–323. [PubMed]
25. Mehrabian M, Qiao JH, Hyman R, Ruddle D, Laughton C, Lusis AJ. Influence of the apoA-II gene locus on HDL levels and fatty streak development in mice. Arterioscler Thromb. 1993;13:1–10. [PubMed]
26. Mehrabian M, Wong J, Wang X, Jiang Z, Shi W, Fogelman AM, Lusis AJ. Genetic Locus in Mice That Blocks Development of Atherosclerosis Despite Extreme Hyperlipidemia. Circ Res. 2001;89:125–130. [PubMed]
27. Welch CL, Bretschger S, Latib N, Bezouevski M, Guo Y, Pleskac N, Liang CP, Barlow C, Dansky H, Breslow JL, Tall AR. Localization of atherosclerosis susceptibility loci to chromosomes 4 and 6 using the Ldlr knockout mouse model. PNAS. 2001;98:7946–7951. [PMC free article] [PubMed]
28. Dansky HM, Shu P, Donavan M, Montagno J, Nagle DL, Smutko JS, Roy N, Whiteing S, Barrios J, McBride TJ, Smith JD, Duyk G, Breslow JL, Moore KJ. A Phenotype-Sensitizing Apoe-Deficient Genetic Background Reveals Novel Atherosclerosis Predisposition Loci in the Mouse. Genetics. 2002;160:1599–1608. [PMC free article] [PubMed]
29. Colinayo VV, Qiao JH, Wang X, Krass KL, Schadt E, Lusis AJ, Drake TA. Genetic loci for diet-induced atherosclerotic lesions and plasma lipids in mice. Mamm Genome. 2003;14:464–471. [PubMed]
30. Ishimori N, Li RH, Kelmenson PM, Korstanje R, Walsh KA, Churchill GA, Forsman-Semb K, Paigen B. Quantitative trait loci analysis for plasma HDL-cholesterol concentrations and atherosclerosis susceptibility between inbred mouse strains C57BL/6J and 129S1/SvImJ. Arteriosclerosis Thrombosis and Vascular Biology. 2004;24:161–166. [PubMed]
31. Wakeland E, Morel L, Achey K, Yui M, Longmate J. Speed congenics: a classic technique in the fast lane (relatively speaking) Immunol Today. 1997;18:472–477. [PubMed]
32. Kozaki K, Kaminski WE, Tang J, Hollenbach S, Lindahl P, Sullivan C, Yu JC, Abe K, Martin PJ, Ross R, Betsholtz C, Giese NA, Raines EW. Blockade of Platelet-Derived Growth Factor or Its Receptors Transiently Delays but Does Not Prevent Fibrous Cap Formation in ApoE Null Mice. Am J Pathol. 2002;161:1395–1407. [PMC free article] [PubMed]
33. Schonherr E, Kinsella MG, Wight TN. Genistein selectively inhibits platelet-derived growth factor-stimulated versican biosynthesis in monkey arterial smooth muscle cells. Arch Biochem Biophys. 1997;339:353–361. [PubMed]
34. Sandy JD, Westling J, Kenagy RD, Iruela-Arispe ML, Verscharen C, Rodriguez-Mazaneque JC, Zimmermann DR, Lemire JM, Fischer JW, Wight TN, Clowes AW. Versican V1 proteolysis in human aorta in vivo occurs at the Glu441-Ala442 bond, a site that is cleaved by recombinant ADAMTS-1 and ADAMTS-4. J Biol Chem. 2001;276:13372–13378. [PubMed]
35. Kenagy RD, Plaas AH, Wight TN. Versican degradation and vascular disease. Trends Cardiovasc Med. 2006;16:209–215. [PMC free article] [PubMed]
36. Lemire JM, Chan CK, Bressler S, Miller J, LeBaron RG, Wight TN. Interleukin-1beta selectively decreases the synthesis of versican by arterial smooth muscle cells. J Cell Biochem. 2007;101:753–766. [PubMed]
37. Han S, Liang CP, DeVries-Seimon T, Ranalletta M, Welch CL, Collins-Fletcher K, Accili D, Tabas I, Tall AR. Macrophage insulin receptor deficiency increases ER stress-induced apoptosis and necrotic core formation in advanced atherosclerotic lesions. Cell Metab. 2006;3:257–266. [PubMed]
38. Kunjathoor VV, Chiu DS, O'Brien KD, LeBoeuf RC. Accumulation of Biglycan and Perlecan, but Not Versican, in Lesions of Murine Models of Atherosclerosis. Arterioscler Thromb Vasc Biol. 2002;22:462–468. [PubMed]
39. Wight TN, Merrilees MJ. Proteoglycans in Atherosclerosis and Restenosis: Key Roles for Versican. Circ Res. 2004;94:1158–1167. [PubMed]
40. Chung IM, Gold HK, Schwartz SM, Ikari Y, Reidy MA, Wight TN. Enhanced extracellular matrix accumulation in restenosis of coronary arteries after stent deployment. Journal of the American College of Cardiology. 2002;40:2072–2081. see comment. [PubMed]
41. Llorente-Cortes V, Otero-Vinas M, Hurt-Camejo E, Martinez-Gonzalez J, Badimon L. Human coronary smooth muscle cells internalize versican-modified LDL through LDL receptor-related protein and LDL receptors. Arterioscler Thromb Vasc Biol. 2002;22:387–393. [PubMed]
42. Evanko SP, Angello JC, Wight TN. Formation of hyaluronan- and versican-rich pericellular matrix is required for proliferation and migration of vascular smooth muscle cells. Arterioscler Thromb Vasc Biol. 1999;19:1004–1013. [PubMed]
43. de La Motte CA, Hascall VC, Calabro A, Yen-Lieberman B, Strong SA. Mononuclear leukocytes preferentially bind via CD44 to hyaluronan on human intestinal mucosal smooth muscle cells after virus infection or treatment with poly(I.C) Journal of Biological Chemistry. 1999;274:30747–30755. [PubMed]
44. Wilkinson TS, Bressler SL, Evanko SP, Braun KR, Wight TN. Overexpression of hyaluronan synthases alters vascular smooth muscle cell phenotype and promotes monocyte adhesion. Journal of Cellular Physiology. 2006;206:378–385. [PubMed]
45. Kawashima H, Hirose M, Hirose J, Nagakubo D, Plaas AH, Miyasaka M. Binding of a large chondroitin sulfate/dermatan sulfate proteoglycan, versican, to L-selectin, P-selectin, and CD44. Journal of Biological Chemistry. 2000;275:35448–35456. [PubMed]
46. Zheng PS, Vais D, Lapierre D, Liang YY, Lee V, Yang BL, Yang BB. PG-M/versican binds to P-selectin glycoprotein ligand-1 and mediates leukocyte aggregation. Journal of Cell Science. 2004;117:5887–5895. [PubMed]
PubReader format: click here to try

Formats:

Related citations in PubMed

See reviews...See all...

Cited by other articles in PMC

See all...

Links

Recent Activity

    Your browsing activity is empty.

    Activity recording is turned off.

    Turn recording back on

    See more...