23.10 Inhibition of ADAMTS-4 Prevents the Development of Aortic Aneurysms and Dissections in Mouse

P. Ren1,2, M. Hughes1,2, L. Zhang1,2, Y. Zheng1,2, S. Krishnamoorthy1,2, J. Coselli1,2,3, Y. Shen1,2,3, S. LeMaire1,2,3  1Baylor College of Medicine,Cardiothoracic Surgery,Houston, TEXAS, USA 2Texas Heart Institute,Cardiovascular Surgery,Houston, TEXAS, USA 3Baylor College of Medicine,Cardiovascular Research Institute,Houston, TEXAS, USA

Introduction: We have previously shown that ADAMTS-4, a disintegrin and metalloproteinase with thrombospondin motifs 4, was significantly elevated in aortic tissue from patients with aortic aneurysms and dissections (AAD), and that ADAMTS-4 contributed to aortic destruction and sporadic AAD development in a mouse model. The current study aimed to determine whether pharmacologic inhibition of ADAMTS-4 can prevent AAD development in mice.

Methods: Four-week old male wild type C57BL/6J mice (n=83) were challenged with high-fat diet for 8 weeks and received angiotensin II infusion during the last 4 weeks. The challenged mice were randomly assigned to receive water (control group, n=50) or 75mg/kg/day of ADAMTS inhibitor pentosan polysulfate sodium (NaPPS) (treatment group, n=33). Incidence of AAD was evaluated by two independent observers. Aortic inflammatory cell infiltrate, ECM destruction, SMC apoptosis, and ADAMTS-4 levels were measured.

Results: NaPPS treatment reduced the development of AAD. The overall incidence of AAD decreased from 78% in the control group to 58% in the NaPPS treatment group (P=0.05). AAD reduction was particularly significant in the descending aorta (36% in control group vs 15% in NaPPS treatment group [P=0.05]) and in the suprarenal aorta (60% in control group vs 33% in NaPPS treatment group [P=0.03]). Furthermore, aortas from the NaPPS treatment group showed greater reductions in ADAMTS-4 expression, macrophage infiltration, elastic fiber destruction and SMC apoptosis as compared to controls. 

Conclusion: ADAMTS inhibitor NaPPS partially reduced the challenge-induced aortic destruction, inflammation, and the development of AAD in mice. Thus, pharmacologically targeting ADAMTS-4 may be a promising therapeutic strategy for preventing AAD formation and progression.