Effect of Bortezomib on Angiotensin Ⅱ-induced Abdominal Aortic Aneurysm in ApoEMice / 中国医学科学院学报

ABSTRACT

Objective To investigate the role of proteasome inhibitor bortezomib (BTZ) in inflammatory response in abdominal aortic aneurysm (AAA) formation induced by angiotensin Ⅱ (Ang Ⅱ). Methods Ang Ⅱ-induced ApoEmice AAA models were established. Forty male ApoEmice (8-10-week-old) were randomly and equally divided into four groupsSham group,BTZ group,Ang Ⅱ group,and Ang Ⅱ+BTZ group.HE staining,immunohistochemical staining,and flow cytometry were used to analyze the inflammatory response. Real-time quantitative polymerase chain reaction (qPCR) was used to analyze the mRNA expression of intercellular cell adhesion molecule-1 (ICAM-1). Western blotting was used to analyze the activation of nuclear factor κB signaling (NF-κB). Results The mean maximum suprarenal aortic diameter (Dmax) of Sham group,BTZ group,Ang Ⅱ group,and Ang Ⅱ+BTZ group were (1.00±0.01),(0.99±0.01),(1.50±0.13),and (1.20±0.04)mm,respectively (F=8.959,P=0.000). The Dmax of Ang Ⅱ group was significantly larger than those of Sham group (P=0.000) and Ang Ⅱ+BTZ group (P=0.015). The incidence of AAA in Ang Ⅱ group,Ang Ⅱ+BTZ group,and Sham group were 60%,17%,and 0,respectively. HE staining revealed that the abdominal aortic wall thickening was more severe in Ang Ⅱ group than in Sham group and Ang Ⅱ+BTZ group,similar with the infiltration of inflammatory cells. Immunohistochemical staining demonstrated that the CD3T lymphocyte count was significantly higher in Ang Ⅱ group than in Sham group (107.9±15.9 vs. 0,P=0.000) and Ang Ⅱ+BTZ group (107.9±15.9 vs. 0.8±0.5,P=0.000). Flow cytometry also demonstrated that the proportion of the CD3T lymphocytes of the Ang Ⅱ group [(13.50±0.69)%] was significantly higher than that in the Ang Ⅱ+BTZ group [(10.40±0.78)%] at week 1 (t=3.009,P=0.040),and the proportion of the CD3T lymphocytes of the Ang Ⅱ group [(22.70±0.93)%] was significantly higher than that in the Ang Ⅱ+BTZ group [(15.10±0.97)%] at week 4 (t=5.654,P=0.005). The qPCR analysis showed that the mRNA expression of ICAM-1 was significantly up-regulated in Ang Ⅱ group than in Sham group (1.93±0.54 vs. 1.00±0.15,P=0.011) and Ang Ⅱ+BTZ group (1.93±0.54 vs. 0.83±0.08,P=0.009). Western blot analysis showed a lower phosphorylation level of inhibitor of NF-κB in the Ang Ⅱ group compared with the Sham group or Ang Ⅱ+BTZ group,accompanied with an increased phosphorylation level of p65. Conclusion Proteasome inhibitor BTZ can attenuate AAA formation partially by regulating T lymphocytes infiltration through regulating the mRNA expression of ICAM-1 regulated by the activation of NF-κB signaling pathway.