Absence of Microbiota (Germ-Free Conditions) Accelerates the Atherosclerosis in ApoE-Deficient Mice Fed Standard Low Cholesterol Diet

作者：Stepankova Renata^*; Tonar Zbynek; Bartova Jirina; Nedorost Lukas; Rossman Pavel; Poledne Rudolf; Schwarzer Martin; Tlaskalova Hogenova Helena

来源：Journal of Atherosclerosis and Thrombosis, 2010, 17(8): 796-804.

DOI：10.5551/jat.3285

• Germ-free mice
• Commensal bacteria
• Atherogenesis

Aim: The aim of our work was to determine the influence of intestinal bacteria on the development of atherosclerotic lesions using apolipoprotein E (ApoE)-deficient knockout mice.
Methods: The experiments were performed on ApoE -/- -deficient mouse strain C57BL/6, bred under germ-free (GF) conditions for two generations or under conventional conditions with defined microflora (CV). The mice were fed a standard low cholesterol diet or cholesterol-rich diet for 3-4 months. We studied the development of advanced lesions in the thoracic and abdominal aorta by histological, morphometric and immunohistological methods.
Results: Conventionally reared ApoE -/- mice (containing no pathogenic intestinal microbiota) and fed a standard low cholesterol diet in contrast to a high cholesterol diet did not develop atherosclerotic aortic plaques. In contrast, ApoE -/- mice reared under germfree conditions for 2 generations and fed a low cholesterol diet exhibited atherosclerotic plaques in the aorta. Characteristic lipid deposition with foam cells and macrophages was found in their arterial walls.
Conclusion: In contrast to the absence of atherosclerotic plaques in conventionally reared ApoE-deficient mice, germ-free ApoE -/- mice consuming the same low cholesterol standard diet developed atherosclerotic plaques in the aorta. Differences in atherosclerotic plaques between GF and CV ApoE -/- mice are not so apparent when mice are fed a high cholesterol diet. Our findings thus document the protective effect of microbiota (commensal bacteria) on atherosclerosis development.

• 出版日期2010