Chlamydia pneumoniae infection accelerates hyperlipidemia induced atherosclerotic lesion development in C57BL/6J mice

Considerable evidence of an association between Chlamydiapneumoniae infections and cardiovascular disease has emerged. Animal models using genetically altered mice and hypercholesterolemic rabbits have shown a pathogenic role of C.pneumoniae in accelerating atherosclerotic plaque development. In the present study, we evaluated the effect of chronic C.pneumoniae infection on atherosclerosis in C57BL/6J mice, fed either a regular chow diet or a high fat, high cholesterol diet. Infected animals on an atherogenic diet developed significantly larger lesion areas compared with control mice at 18 weeks (2.5-fold increase; 4177±777 vs. 1650±808 μm2; P<0.05) and 24 weeks of age (3.3-fold increase; 14 139±4147 vs. 4298±869 μm2; P<0.02). This study shows that chronic C.pneumoniae infection accelerates atherosclerotic lesion development in diet induced hypercholesterolemic mice, indicating that C.pneumoniae is a co-risk factor of hyperlipidemia in atherogenesis.