(Circulation. 1999;99:276-283.)
© 1999 American Heart Association, Inc.
Basic Science Reports |
From the Departments of Cardiology (E.L., P.D., H.W., E.D.d.M.) and Pathology (M.D.), Cardiovascular Research Institute Maastricht, Universiteit Maastricht, and the Department of Human Genetics, University of Leiden (M.H.) and TNO-PG Gaubius Laboratory, Leiden (L.H.), Netherlands; and the Department of Pathology (M.K.), AZ Middelheim, Antwerp, Belgium.
Correspondence to Ebo D. de Muinck, MD, PhD, Department of Cardiology, Academic Hospital Maastricht, PO Box 5800, P. Debeyelaan 25, 6202 AZ Maastricht, 6229 HX Maastricht, Netherlands. E-mail e.demuinck{at}cardio.azm.nl
| Abstract |
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Methods and ResultsDiet duration was correlated with a craniocaudal progression of lesion development and with an increase in severity of the lesion. Typically, the lesions contained smooth muscle cells, macrophages, and T lymphocytes and were covered by an intact endothelium. Whereas DNA synthesis (BrdU uptake) was usually elevated in type II lesions (8.6±0.8% versus 1.0±0.2% in the nondiseased arterial wall; P<0.05), apoptosis was found primarily in advanced lesions (type IV, 1.3±0.1% and type V, 1.2±0.2% versus 0.04±0.04% in the nondiseased arterial wall [P<0.05]). Cell phenotyping revealed that the majority of DNA synthesis and apoptosis was confined to the macrophage-derived foam cell (68.6±3.0% and 82.2±4.6%, respectively).
ConclusionsThis study shows that in APOE*3-Leiden mice, duration of an HFC diet is associated with (1) a craniocaudal progression of lesion development and (2) an increased complexity of atherosclerotic lesions. Furthermore, DNA synthesis is predominant in early lesions, whereas apoptosis is present mainly in more advanced lesions. Both parameters of cell turnover are confined primarily to the macrophage-derived foam cell.
Key Words: atherosclerosis genetics apoptosis
| Introduction |
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The data published so far show that APOE*3-Leiden mice exhibit severe hypercholesterolemia when they are fed a high-fat/high-cholesterol (HFC) diet. However, atherosclerosis in these mice has been described only after relatively short periods of cholesterol feeding.3 5 6 To date, no detailed description of lesion morphology including data on cell turnover is available. Also, data on the progression of lesions along the entire arterial tree and long-term observations on the progression of plaque extent and complexity are lacking. This study was initiated to provide these data.
| Methods |
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Diet
Before entry into the study, animals were kept on standard mouse
chow (SRM-A, Hope Farms). At the age of 37±0.6 weeks (mean±SEM), the
animals were put on a diet containing 15% cacao butter, 0.5% cholate,
1% cholesterol, 40.5% sucrose, 10% corn starch, 1% corn
oil, and 4.7% cellulose (Hope Farms)7 for 1 (n=4), 4
(n=9), 6 (n=12), 9 (n=12), and 12 (n=12) months. Control APOE*3-Leiden
(n=6) and C57Bl/6J (n=6) mice received standard mouse chow for 9
months. To label DNA-synthesizing cells, 6 transgenic animals of the
6-month diet group received 5'-bromo-2'-deoxyuridine (BrdU, Serva;
infusion rate, 13 mg · kg-1 ·
d-1) by an osmotic minipump (Alzet 2001, Alza
Corp) for the 7 days before they were euthanized. Pumps were placed
subcutaneously between the shoulder blades under ether
anesthesia. All mice were housed under standard conditions.
The study was approved by the institutional committee for the welfare
of laboratory animals of the University of Maastricht.
Tissue Handling
After completion of the diet according to protocol, each mouse
was anesthetized with xylazine 0.0025 mL/g and ketamine
0.001 mL/g IP. Blood (0.5 to 1 mL) was collected from the caval vein
for the assessment of lipid profile, and the arterial tree
was perfused with 0.9% NaCl (3 minutes) and 10% phosphate-buffered
formalin (pH 7.4, 3 minutes), both containing 20%
nitroglycerin, through a catheter into the left
ventricular apex. Subsequently, the complete
arterial tree was taken out and fixed overnight in 10%
phosphate-buffered formalin.
All arterial segments indicated in Figure 1
were processed and embedded in
paraffin, and 4-µm sections were stained with hematoxylin and eosin.
Atherosclerotic lesions were classified according to the guidelines
given by the American Heart Association (AHA)8 by 1
investigator (E.L.), who was blinded to presence or absence as well as
duration of diet and to genotype.
|
Assessment of Lipid Profile
Total serum cholesterol and
triglycerides (but not free glycerol) were measured as
described previously.3
Immunohistochemistry
Study 1: Diet-Dependent Lesion Progression
Because of its size and because all lesion types also
developed in the aortic arch, we concentrated the immunohistochemical
analyses on this segment. Parallel sections of the aortic arch
were immunolabeled with either ED-19 for the detection of
macrophage-derived foam cells, CD-3 (CD-3, monoclonal,
1:200, Dako A0452) for the detection of T lymphocytes,
-smooth
muscle actin (monoclonal, 1:500, FITC-labeled, Sigma Chemical Co) or
desmin (monoclonal, 1:100, Organon MDEII, Eurodiagnostics)
as smooth muscle cell markers, or factor VIII (polyclonal, 1:2000, Dako
A0082) for the detection of endothelial cells.
Immunostaining was performed according to conventional
methods with biotin- or FITC (
-smooth muscle actin)labeled
secondary antibodies and 3,3'-diaminobenzidine (DAB) as a chromogen.
Sections were counterstained with hematoxylin and mounted with
coverslips. In all immunohistochemistry, sections treated without the
respective primary antibody served as controls.
Study 2: Cell Turnover in Atherosclerotic Lesions
BrdU Staining.
After dehydration, the sections were incubated for 2 hours in 3% EDTA
(Merck) at pH 7.2 to block nonspecific staining of calcium-containing
vesicles.10 BrdU staining was performed as described
previously,11 with DAB as the chromogen.
TUNEL Staining.
Parallel sections were used for the TUNEL staining. After dehydration,
sections were incubated with 3% citric acid to inhibit aspecific
binding of the nucleotides to calcium-containing vesicles.
TUNEL staining was performed as described previously.10
Amino-3-9-ethylcarbazole (AEC) was used as chromogen. Sections were
counterstained with hematoxylin and mounted with coverslips. Negative
controls included omission of TdT from the labeling mixture. Tonsils
were used as a positive control.
Cell Phenotypes.
Parallel sections of atherosclerotic lesions of the 6 APOE*3-Leiden
mice were immunolabeled with ED-1,
-smooth muscle actin, CD-3, and
factor VIII as described above.
| Cell Counting |
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The labeling index, defined as the total number of positive cells divided by the total number of cells, was calculated for the entire atherosclerotic lesion, including the underlying media. This was performed separately for the BrdU- and TUNEL-stained sections. Labeling indices were also determined in different sites of the lesion: the underlying media, the endothelial coverage, the shoulder region, the lipid core, and the fibrous cap. Furthermore, the distribution of the different immunophenotypes of BrdU- or TUNEL-positive cells was quantified. The immunophenotype of 89.1±1.4% of the DNA-synthesizing cells and 97.3±2.2% of the apoptotic cells could be determined by the above-described panel of antibodies (CD3, ASMA, FVIII, ED-1).
All measurements were performed by 1 investigator (E.L.). Intraobserver variation was <10%.
| Statistical Analysis |
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Study 2: Cell Turnover in Atherosclerotic Lesions
Data are expressed as mean±SEM.
To test whether lesions of the same type in different mice and lesions of the same type at different sites of the arterial tree were comparable, a 1-way ANOVA was performed on both parameters. This was performed for both BrdU- and TUNEL-stained sections. Because no significant difference was found, lesions of the different mice and at the different sites of the arterial tree were assumed to be comparable.
Subsequently, a Mann-Whitney U test was used for comparisons between the lesion types. In all tests, the level of statistical significance was assumed to be at P<0.05.
| Results |
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Atherosclerotic Lesions in APOE*3-Leiden Transgenic Mice
Atherosclerotic lesions developed in the aorta and large vessels
in all APOE*3-Leiden mice on an HFC diet (Figure 1
). Lesions
developed in the proximal coronary arteries (Figure 2A
), the aortic root, the aortic arch and
its main branch points (Figure 2B
), the thoracic aorta, the
abdominal aorta, the renal artery branch points (Figure 2C
), the
abdominal aorta bifurcation, and the iliac artery bifurcations. Almost
all lesion types were observed: initial lesions with isolated
macrophage foam cells (type I), fatty streaks with mainly
intracellular lipid accumulation (type II, Figure 3A
), and intermediate lesions with type
II changes and small extracellular lipid pools (type III). Also, more
advanced lesions could be detected, such as an atheroma
with type II changes and a core of extracellular lipid (type IV,
Figures 2B
and 3D
) as well as fibroatheromata
with a lipid core and a fibrotic layer (Figure 2A
and 2C
), or with multiple lipid cores and fibrotic layers (type Va),
or mainly calcific (type Vb, Figures 2D
and 3E
) or
fibrotic (type Vc) fibroatheromata. Type VI lesions with
plaque rupture, thrombus formation, and hemorrhage were not
observed.
|
|
In the APOE*3-Leiden mice on normal chow, only initial type I and II lesions were observed. Wild-type mice on normal chow did not develop atherosclerosis.
Immunophenotype
Macrophages were not present in the normal media but
were found in the media and intima of all lesion types (Figure 3A
). In advanced lesion types, lipid-filled macrophages
were present primarily in the shoulder region of the lesion. T
lymphocytes were present primarily in advanced lesion types (IV to
Vb), especially in the shoulder region and fibrous cap (Figure 3B
).
Both the media of nondiseased vessel segments and the nondiseased
media below an atherosclerotic lesion showed no desmin-positive
vascular smooth muscle cells (VSMCs) (Figure 3C
and 3D
).
However, desmin-positive VSMCs were present in the intima and
fibrous cap of advanced lesions (Figure 3D
). All atherosclerotic
lesions contained
-smooth muscle actinpositive VSMCs, both in the
nondiseased media below the lesion and in the lesion itself (Figure 3E
). They were most numerous in the fibrous cap of advanced
lesion types. The endothelial coverage of the lesions
remained intact, even in very advanced lesions (Figure 3F
).
Effect of Diet Duration on Lesion Progression
The variability in the development of atherosclerotic lesions
between mice in 1 diet group was remarkably low, and diet duration
seemed to predict lesion type and site (data not shown). After 1 month
of HFC diet, initial type II lesions were observed only in the aortic
root, the aortic arch and its main branches, the carotid artery
bifurcations, and the thoracic aorta. Below the diaphragm, no lesions
were observed.
After 4 months of HFC diet, initial type II lesions were present in
the coronary arteries. Advanced atherosclerotic lesions (type
IV) with a core of extracellular lipid were present in the aortic
root, the aortic arch and its main branch points, and the right carotid
artery bifurcation. Below the diaphragm, only initial lesions (type I
and II) with foam cells in the subendothelium were
observed (Figure 1
).
After 6 months of HFC, advanced type IV lesions had developed in the
coronary arteries (Figure 2A
). Furthermore, type V
lesions with a fibrous cap and a lipid core were present in the
aortic arch and its main branches (Figure 2B
). Type IV lesions
had also developed in the abdominal aorta and renal artery branch
points.
After a diet period of 9 months, severe calcification of the
atherosclerotic lesions (type Vb) was observed in the aortic arch and
its main branch points (Figure 2D
). Type V lesions were
present in the right carotid artery bifurcation. Type IV lesions
had developed in the thoracic aorta, in the abdominal aorta, and at the
renal artery branch points. However, in the abdominal aorta and the
iliac artery bifurcations, only type II lesions could be observed.
After 12 months of HFC diet, lesions in the aortic arch showed
calcification (type Vb), and type V lesions were observed at both the
right and left carotid artery bifurcations. Moreover, 5 of 12 mice
showed calcifications in their coronary arteries. Furthermore,
at the abdominal aorta bifurcation and the iliac artery bifurcations,
advanced lesions (type IV) had developed (Figure 1
).
Study 2: Cell Turnover in Atherosclerotic Lesions
In total, 135 lesions were investigated throughout the
arterial tree of the 6 APOE*3-Leiden mice fed an HFC diet
for 6 months. BrdU- and TUNEL-positive nuclei were counted in all
lesion types except in type I lesions, because the total number of
nuclei in this lesion type was too small. Thirty nondiseased
arterial segments served as controls.
DNA Synthesis
In all lesion types, DNA synthesis was significantly elevated
compared with the nondiseased arterial wall (Figure 4
). The highest BrdU labeling was
found in type II (fatty streak) lesions (8.6±0.8% versus 1.0±0.2%
in the nondiseased arterial wall; P<0.05)
(Figure 4A
). With progression of severity of the lesion, DNA
synthesis decreased to 5.8±0.7% in complex type V lesions
(P<0.05 versus type 2).
|
Not only the level but also the site of DNA synthesis changed with
progression of the lesion (Figure 4D
). In type II lesions, most
DNA-synthesizing cells were found in the media (77.9% of all
DNA-synthesizing cells), whereas in type III, IV, and V lesions, only a
small amount of DNA-synthesizing cells was found in the media (17.1%,
14.1%, and 12.1%, respectively, P<0.05). With the
development of a shoulder region in type III and IV lesions, DNA
synthesis shifted to that region (32.9% and 41.0% of all
DNA-synthesizing cells, respectively) as well as to the
endothelial cells covering the lesion (30.0% and
32.1%, respectively). The percentage of DNA synthesis of
endothelial cells covering type III and IV lesions, was
significantly increased compared with both type II lesions and the
nondiseased arterial wall (P<0.05). When
atherosclerosis had progressed to advanced type V
lesions with a fibrous cap and a lipid core, DNA-synthesizing cells
were located in the shoulder region (36.2%) and fibrous cap (29.3%),
whereas the fraction of DNA-synthesizing cells of
endothelial cells covering the fibrous cap showed a
significant decrease to 12.1% compared with type IV lesions
(P<0.05). DNA synthesis in the lipid core of type IV and V
lesions was low (12.8% and 12.1% of all DNA-synthesizing cells,
respectively).
Subsequent immunolabeling (Figure 4
) showed that 68.6±3.0% of
the DNA-synthesizing cells were macrophage-derived foam
cells, 14.5±2.5% VSMCs, 1.3±0.3% T lymphocytes, and 5.3±1.2%
endothelial cells of the endothelial
coverage. In all lesion types, the majority of DNA-synthesizing cells
were foam cellderived macrophages, but the ratio of
macrophage-derived foam cells to VSMCs decreased with
lesion development. In early type II lesions, this ratio was 76.9,
whereas in complex type V lesions, this ratio had decreased to 3.7
(P<0.05).
Apoptosis
The distribution of apoptotic nuclei in the different
lesion types differed from the distribution of DNA-synthesizing nuclei
(Figure 5
). In type II and III lesions,
the apoptotic labeling index was not different from the
apoptotic labeling index in the nondiseased
arterial wall. The percentage of apoptotic nuclei
was elevated only in type IV and V lesions (1.3±0.1% in type IV and
1.2±0.2% in type V versus 0.04±0.04% in the nondiseased
arterial wall). The majority of apoptotic nuclei
was located in the lipid core of these type IV and V lesions (81.9%
and 79.5% of all apoptotic cells, respectively). Furthermore,
only low levels of apoptosis were found in the fibrous cap
(9.0% of all apoptotic cells)
|
Cell phenotyping revealed that the majority of apoptosis was
confined to the macrophage-derived foam cells (82.2±4.6%)
(Figure 5
). Apoptosis in other cell types was rarely
observed.
| Discussion |
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So far, few human data on DNA synthesis during the entire process of atherogenesis are available.14 Orekhov et al14 report peak levels of DNA synthesis in lipid-rich lesions, whereas DNA synthesis in fibrous lesions is much lower. The majority of data on DNA synthesis in human atherosclerosis are confined to advanced lesions only. They show low levels of DNA synthesis (0% to 2%),15 16 17 18 but this level is significantly higher than in the nondiseased arterial wall.14 15 18 19 One study on DNA synthesis in early fatty-streak lesions also reports low values of DNA synthesis (0% to 2%).20 DNA synthesis in these human lesions is confined primarily to either the macrophage-derived foam cell15 17 18 or the VSMC.16 As in human in vitro studies21 and rabbit models,22 23 24 the APOE*3-Leiden mouse exhibits a DNA-synthesis peak in early lesion types. DNA synthesis in advanced lesion types is low, which is in accordance with the low levels of DNA synthesis found in advanced human atheromata.15 16 17 18 Interestingly, we observed 2 kinds of type II lesions. The early type II lesion contained macrophage-derived foam cells that were located only in the media, whereas the late type II lesion contained macrophage-derived foam cells in the intima. We defined them as type IIa and IIb, respectively. In the early type IIa lesions, DNA synthesis was significantly elevated compared with the late type IIb lesions (10.3±0.8% in type IIa versus 6.0±1.3% in type IIb). In both lesion types, the majority of DNA-synthesizing cells were macrophage-derived foam cells (91.1% and 94.2%, respectively). The fact that the intima of a nondiseased vessel in the mouse consists of only a very small subendothelial layer may explain our observation that early lesions contain medial macrophage-derived foam cells, whereas in advanced lesions, these macrophages are present in the intima. Thus, it seems that the first migrating macrophage-derived foam cells are transported from the blood into the most luminal layer of the media. With the accumulation of increased numbers of macrophage-derived foam cells (type IIb through Vb), a neointima develops.
Enhanced rates of apoptotic cell death have also been observed in advanced human atherosclerosis.25 26 27 28 In a recent study, we found that fatty streak lesions are characterized by very low levels of apoptosis, whereas advanced atherosclerotic lesions showed remarkable levels of cell death.29 In human atheromata, the apoptotic labeling index varies from 0% to 40%, and apoptotic nuclei are present primarily in the lipid core and regions adjacent to the lipid core, but also in the fibrous cap.25 27 28 The majority of apoptotic nuclei have been found in macrophages25 27 and T lymphocytes.26 Also, in APOE*3-Leiden mice, apoptosis was confined to the advanced stages, albeit at fairly low levels. Moreover, apoptosis in the fibrous cap was a rare phenomenon. Whether this phenomenon can be an explanation for the apparent plaque stability observed in these mice remains to be investigated.
One of the major differences of atherosclerosis in the APOE*3-Leiden mouse with human atherosclerosis is the absence of plaque rupture, thrombus formation, and/or hemorrhage in the atherosclerotic plaque.30 We have no explanation for the apparent stability of the atherosclerotic plaques in the APOE*3-Leiden mouse. One of the possibilities is that the morphologically intact endothelial layer that covers all lesion types in the APOE*3-Leiden mouse prevents lesions from rupturing. Another explanation is the low level of apoptosis in the fibrous cap in these mice.
The data presented here may have clinical implications. It is known that treatment with HMG-CoA reductase inhibitors can slow the progression of atherosclerosis.31 One of the mechanisms that have been described is the inhibition of DNA synthesis in both VSMCs and macrophages.32 33 Our data imply that these agents may be most successful in slowing the progression of atherosclerosis when they are applied early in the disease process, when DNA synthesis is usually elevated. Conversely, it may be more interesting to look at agents that modulate apoptosis. Because apoptosis is a late event in atherogenesis, inhibition of apoptosis may both slow the progression of atherosclerosis and be effective in preventing the conversion from stable into unstable atherosclerotic lesions.
In the present article, we demonstrate that APOE*3-Leiden mice show a highly reproducible diet- and time-dependent craniocaudal progression of atherosclerosis extent and plaque complexity. We found a peak in DNA synthesis in early lesions and a peak in apoptosis in late lesions, both which are confined to macrophage-derived foam cells. Diet dependency, predilection site, plaque composition, and cell turnover make the APOE*3-Leiden mouse a suitable model to study different aspects of early atherogenesis and the evaluation of pharmacological and nonpharmacological interventions.
| Acknowledgments |
|---|
Received April 29, 1998; revision received August 28, 1998; accepted September 8, 1998.
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F.C. Gibson III, H. Yumoto, Y. Takahashi, H.-H. Chou, and C.A. Genco Innate Immune Signaling and Porphyromonas gingivalis-accelerated Atherosclerosis Journal of Dental Research, February 1, 2006; 85(2): 106 - 121. [Abstract] [Full Text] [PDF] |
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B. M. van den Berg, J. A. E. Spaan, T. M. Rolf, and H. Vink Atherogenic region and diet diminish glycocalyx dimension and increase intima-to-media ratios at murine carotid artery bifurcation Am J Physiol Heart Circ Physiol, February 1, 2006; 290(2): H915 - H920. [Abstract] [Full Text] [PDF] |
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V. L. Sales, G. K. Sukhova, M. A. Lopez-Ilasaca, P. Libby, V. J. Dzau, and R. E. Pratt Angiotensin Type 2 Receptor Is Expressed in Murine Atherosclerotic Lesions and Modulates Lesion Evolution Circulation, November 22, 2005; 112(21): 3328 - 3336. [Abstract] [Full Text] [PDF] |
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L. Verschuren, R. Kleemann, E. H. Offerman, A. J. Szalai, S. J. Emeis, H. M. G. Princen, and T. Kooistra Effect of Low Dose Atorvastatin Versus Diet-Induced Cholesterol Lowering on Atherosclerotic Lesion Progression and Inflammation in Apolipoprotein E*3-Leiden Transgenic Mice Arterioscler Thromb Vasc Biol, January 1, 2005; 25(1): 161 - 167. [Abstract] [Full Text] [PDF] |
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N. M. Morel, J. M. Holland, J. van der Greef, E. W. Marple, C. Clish, J. Loscalzo, and S. Naylor Primer on Medical Genomics Part XIV: Introduction to Systems Biology--A New Approach to Understanding Disease and Treatment Mayo Clin. Proc., May 1, 2004; 79(5): 651 - 658. [Abstract] [PDF] |
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M. Valgimigli, L. Agnoletti, S. Curello, L. Comini, G. Francolini, F. Mastrorilli, E. Merli, R. Pirani, G. Guardigli, P. G. Grigolato, et al. Serum From Patients With Acute Coronary Syndromes Displays a Proapoptotic Effect on Human Endothelial Cells: A Possible Link to Pan-Coronary Syndromes Circulation, January 21, 2003; 107(2): 264 - 270. [Abstract] [Full Text] [PDF] |
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C. Kluft, R. Kleemann, and M.P.M. de Maat How best to counteract the enemies? By controlling inflammation in the coronary circulation Eur. Heart J. Suppl., November 1, 2002; 4(suppl_G): G53 - G65. [Abstract] [PDF] |
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R Ezzahiri, H.J.M.G Nelissen-Vrancken, H.A.J.M Kurvers, F.R.M Stassen, I Vliegen, G.E.L.M Grauls, M.M.L van Pul, P.J.E.H.M Kitslaar, and C.A Bruggeman Chlamydophila pneumoniae (Chlamydia pneumoniae) accelerates the formation of complex atherosclerotic lesions in Apo E3-Leiden mice Cardiovasc Res, November 1, 2002; 56(2): 269 - 276. [Abstract] [Full Text] [PDF] |
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J.H.P. Lardenoye, M.R. de Vries, C.W.G.M. Lowik, Q. Xu, C.R. Dhore, J.P.M. Cleutjens, V.W.M. van Hinsbergh, J.H. van Bockel, and P.H.A. Quax Accelerated Atherosclerosis and Calcification in Vein Grafts: A Study in APOE*3 Leiden Transgenic Mice Circ. Res., October 4, 2002; 91(7): 577 - 584. [Abstract] [Full Text] [PDF] |
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E.V. Rouwet, A.N. Tintu, M.W.M. Schellings, M. van Bilsen, E. Lutgens, L. Hofstra, D.W. Slaaf, G. Ramsay, and F.A.C. le Noble Hypoxia Induces Aortic Hypertrophic Growth, Left Ventricular Dysfunction, and Sympathetic Hyperinnervation of Peripheral Arteries in the Chick Embryo Circulation, June 11, 2002; 105(23): 2791 - 2796. [Abstract] [Full Text] [PDF] |
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S. M. Lessner, H. L. Prado, E. K. Waller, and Z. S. Galis Atherosclerotic Lesions Grow Through Recruitment and Proliferation of Circulating Monocytes in a Murine Model Am. J. Pathol., June 1, 2002; 160(6): 2145 - 2155. [Abstract] [Full Text] [PDF] |
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J. H. J. Vernooy, M. A. Dentener, R. J. van Suylen, W. A. Buurman, and E. F. M. Wouters Long-Term Intratracheal Lipopolysaccharide Exposure in Mice Results in Chronic Lung Inflammation and Persistent Pathology Am. J. Respir. Cell Mol. Biol., January 1, 2002; 26(1): 152 - 159. [Abstract] [Full Text] [PDF] |
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S. W.E. van de Poll, T. J. Romer, O. L. Volger, D. J.M. Delsing, T. C. Bakker Schut, H. M.G. Princen, L. M. Havekes, J. W. Jukema, A. van der Laarse, and G. J. Puppels Raman Spectroscopic Evaluation of the Effects of Diet and Lipid-Lowering Therapy on Atherosclerotic Plaque Development in Mice Arterioscler Thromb Vasc Biol, October 1, 2001; 21(10): 1630 - 1635. [Abstract] [Full Text] [PDF] |
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E. Lutgens, E. D. de Muinck, S. Heeneman, and M. J.A.P. Daemen Compensatory Enlargement and Stenosis Develop in ApoE-/- and ApoE*3-Leiden Transgenic Mice Arterioscler Thromb Vasc Biol, August 1, 2001; 21(8): 1359 - 1365. [Abstract] [Full Text] [PDF] |
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D. J. M. Delsing, E. H. Offerman, W. van Duyvenvoorde, H. van der Boom, E. C. M. de Wit, M. J. J. Gijbels, A. van der Laarse, J. W. Jukema, L. M. Havekes, and H. M. G. Princen Acyl-CoA:Cholesterol Acyltransferase Inhibitor Avasimibe Reduces Atherosclerosis in Addition to Its Cholesterol-Lowering Effect in ApoE*3-Leiden Mice Circulation, April 3, 2001; 103(13): 1778 - 1786. [Abstract] [Full Text] [PDF] |
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M. Kliffen, E. Lutgens, M. J A P Daemen, E. D de Muinck, C. M Mooy, and P. T V M de Jong The APO*E3-Leiden mouse as an animal model for basal laminar deposit Br J Ophthalmol, December 1, 2000; 84(12): 1415 - 1419. [Abstract] [Full Text] |
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K. Walsh, R. C. Smith, and H.-S. Kim Vascular Cell Apoptosis in Remodeling, Restenosis, and Plaque Rupture Circ. Res., August 4, 2000; 87(3): 184 - 188. [Full Text] [PDF] |
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J. H. P. Lardenoye, D. J. M. Delsing, M. R. de Vries, M. M. L. Deckers, H. M. G. Princen, L. M. Havekes, V. W. M. van Hinsbergh, J. H. van Bockel, and P. H. A. Quax Accelerated Atherosclerosis by Placement of a Perivascular Cuff and a Cholesterol-Rich Diet in ApoE*3Leiden Transgenic Mice Circ. Res., August 4, 2000; 87(3): 248 - 253. [Abstract] [Full Text] [PDF] |
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E. Lutgens, K. B. J. M. Cleutjens, S. Heeneman, V. E. Koteliansky, L. C. Burkly, and M. J. A. P. Daemen Both early and delayed anti-CD40L antibody treatment induces a stable plaque phenotype PNAS, June 20, 2000; 97(13): 7464 - 7469. [Abstract] [Full Text] [PDF] |
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W. L van Heerde, S. Robert-Offerman, E. Dumont, L. Hofstra, P. A Doevendans, J. F.M Smits, M. J.A.P Daemen, and C. P.M Reutelingsperger Markers of apoptosis in cardiovascular tissues: focus on Annexin V Cardiovasc Res, February 1, 2000; 45(3): 549 - 559. [Abstract] [Full Text] [PDF] |
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M. M Kockx and A. G Herman Apoptosis in atherosclerosis: beneficial or detrimental? Cardiovasc Res, February 1, 2000; 45(3): 736 - 746. [Abstract] [Full Text] [PDF] |
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K. Walsh and J. M. Isner Apoptosis in inflammatory-fibroproliferative disorders of the vessel wall Cardiovasc Res, February 1, 2000; 45(3): 756 - 765. [Abstract] [Full Text] [PDF] |
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B. J.M. van Vlijmen, G. Gerritsen, A. L. Franken, L. S.M. Boesten, M. M. Kockx, M. J. Gijbels, M. P. Vierboom, M. van Eck, B. van de Water, T. J.C. van Berkel, et al. Macrophage p53 Deficiency Leads to Enhanced Atherosclerosis in APOE*3-Leiden Transgenic Mice Circ. Res., April 27, 2001; 88(8): 780 - 786. [Abstract] [Full Text] [PDF] |
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