C-reactive protein deficiency ameliorates experimental abdominal aortic aneurysms

Area of Science:

• Vascular Biology
• Inflammation Research
• Biochemistry

Background:

• Elevated C-reactive protein (CRP) levels are observed in patients with abdominal aortic aneurysms (AAAs).
• The specific role of CRP in the pathogenesis of AAA remains largely uninvestigated.

Purpose of the Study:

• To investigate the contribution of C-reactive protein (CRP) to the development of abdominal aortic aneurysms (AAAs).

Main Methods:

• Experimental abdominal aortic aneurysms (AAAs) were induced in C-reactive protein (CRP) deficient and wild-type (WT) mice using porcine pancreatic elastase.
• Aortic diameters were measured, and histological and immunohistochemical analyses were performed to assess AAA pathologies.
• Macrophage activation was evaluated in peritoneal macrophages in vitro.

Main Results:

• CRP deficiency significantly suppressed AAA development, evidenced by reduced aortic dilation compared to WT mice.
• CRP deficient mice exhibited preserved medial elastin and reduced macrophage accumulation in aneurysmal aortas.
• Matrix metalloproteinase 2 expression was attenuated in CRP deficient mice, while effects on smooth muscle loss, lymphocyte accumulation, and MMP-9 were not significant.

Conclusions:

• C-reactive protein (CRP) deficiency attenuates experimental abdominal aortic aneurysms (AAAs).
• Key mechanisms include reduced elastin destruction, decreased macrophage accumulation, and suppressed matrix metalloproteinase 2 expression.