Abstract

Up-to-date molecular biological methods permit efficient identification and characterization of new genes. Using Affimetrix microarrays, we studied gene expression in thoracic aorta of ApolipoproteinE − / − ( ApoE − / − ) animals fed either a normal or a high cholesterol diet (HCD) for 4 weeks. Over 200 genes were differentially regulated under these conditions. Interestingly, most components of the complement pathway were upregulated after a HCD, with the complement component 3a receptor (C3aR) exhibiting the highest induction. To study the relevance of the complement pathway in atherogenesis, ApoE − / − C3aR − / − mice and ApoE − / − controls were compared after 12 weeks of a HCD. ApoE − / − C3aR − / − animals had on average 14.11%±3.16% of descending aortas occupied by atherosclerotic plaques, which was nearly 2-fold more than controls (7.11%±1.01%). This effect was associated with increased accumulation of leukocytes in atherosclerotic plaques of ApoE − / − C3aR − / − mice. Moreover, production of the proinflammatory cytokines interferon gamma (IFN γ ), chemokine (C-C) ligand-5 (CCL5), tumor necrosis factor beta (TNF β ), interleukin-12 (IL-12), and interleukin-18 (IL-18) was higher upon C3aR deletion. This study demonstrates that C3aR protects from atherosclerosis development, emphasizing the complex role of the complement cascade in the development of inflammation during atherogenesis.

Full Text
Published version (Free)

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call