A high fat/high carbohydrate diet induces aortic valve disease in C57BL/6J mice.
OBJECTIVE
The purpose of this study was to compare aortic valve function and morphology in adult wild-type (WT) mice and in low-density lipoprotein receptor-deficient (LDLr-/-) mice fed or not fed a high-fat/high-carbohydrate (HF/HC) diet.


BACKGROUND
Observations suggest a link between degenerative aortic valve stenosis (AS) and atherosclerosis. Aortic valve stenosis has been successfully induced in animal models of extreme hypercholesterolemia, but these models are less relevant to humans. It is not known if a proatherogenic HF/HC diet without added cholesterol could have the same negative impacts.


METHODS
Forty C57BL/6J mice were divided into four groups: WT + normal diet, WT + HF/HC diet, LDLr-/- with a normal diet, and LDLr-/- with a HF/HC diet. Aortic valve function and histology were evaluated by echocardiography after four months.


RESULTS
Wild-type mice on a HF/HC diet became mildly hypercholesterolemic, obese, and hyperglycemic. As expected, LDLr-/- mice became severely hypercholesterolemic. Both WT and LDLr-/- mice on a HF/HC diet displayed smaller valve areas and higher transvalvular velocities (p < 0.01) after four months. Aortic valve leaflets were thicker and infiltrated with lipids and macrophages in both HF/HC groups.


CONCLUSIONS
A HF/HC diet in mice results in significant aortic valve abnormalities. Putting WT mice on a HF/HC diet reproduced a combination of atherogenic factors (obesity, mild dyslipidemia, and hyperglycemia) more commonly encountered in humans than isolated severe hypercholesterolemia. Severe hypercholesterolemia was not a prerequisite in our model. This experimental model suggests that AS development is multifactorial and that hypercholesterolemia should not be the only target in this disease.
Groupe de recherche en valvulopathies, Institut de cardiologie de Québec, Québec, Canada.
Marie-Claude
MC
Drolet
Elise
E
Roussel
Yves
Y
Deshaies
Jacques
J
Couet
Marie
M
Arsenault
D000818:Animals; D001024:Aortic Valve Stenosis / Q000209:etiology*; D050197:Atherosclerosis / Q000209:etiology; D004040:Dietary Carbohydrates / Q000009:adverse effects*; D004041:Dietary Fats / Q000009:adverse effects*; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL
D004040:Dietary Carbohydrates; D004041:Dietary Fats