[HTML][HTML] TGF-β activity protects against inflammatory aortic aneurysm progression and complications in angiotensin II–infused mice

Y Wang, H Ait-Oufella, O Herbin… - The Journal of …, 2010 - Am Soc Clin Investig
Y Wang, H Ait-Oufella, O Herbin, P Bonnin, B Ramkhelawon, S Taleb, J Huang, G Offenstadt…
The Journal of clinical investigation, 2010Am Soc Clin Investig
Complicated abdominal aortic aneurysm (AAA) is a major cause of mortality in elderly men.
Ang II–dependent TGF-β activity promotes aortic aneurysm progression in experimental
Marfan syndrome. However, the role of TGF-β in experimental models of AAA has not been
comprehensively assessed. Here, we show that systemic neutralization of TGF-β activity
breaks the resistance of normocholesterolemic C57BL/6 mice to Ang II–induced AAA
formation and markedly increases their susceptibility to the disease. These aneurysms …
Complicated abdominal aortic aneurysm (AAA) is a major cause of mortality in elderly men. Ang II–dependent TGF-β activity promotes aortic aneurysm progression in experimental Marfan syndrome. However, the role of TGF-β in experimental models of AAA has not been comprehensively assessed. Here, we show that systemic neutralization of TGF-β activity breaks the resistance of normocholesterolemic C57BL/6 mice to Ang II–induced AAA formation and markedly increases their susceptibility to the disease. These aneurysms displayed a large spectrum of complications on echography, including fissuration, double channel formation, and rupture, leading to death from aneurysm complications. The disease was refractory to inhibition of IFN-γ, IL-4, IL-6, or TNF-α signaling. Genetic deletion of T and B cells or inhibition of the CX3CR1 pathway resulted in partial protection. Interestingly, neutralization of TGF-β activity enhanced monocyte invasiveness, and monocyte depletion markedly inhibited aneurysm progression and complications. Finally, TGF-β neutralization increased MMP-12 activity, and MMP-12 deficiency prevented aneurysm rupture. These results clearly identify a critical role for TGF-β in the taming of the innate immune response and the preservation of vessel integrity in C57BL/6 mice, which contrasts with its reported pathogenic role in Marfan syndrome.
The Journal of Clinical Investigation