The Role Of P-selectin Glycoprotein Ligand-1 In Deoxycorticosterone Acetate Plus Salt Induced Mouse Aortic Aneurysm Model

Objective To investigate the relationship between P-selectin glycoprotein ligand-1and aortic aneurysm and explore its mechanism in deoxycorticosterone acetate（DOCA）plus salt induced mouse aortic aneurysm model.Methods 1.Aortic aneurysm model was induced by DOCA plus salt（DOCA+SALT）treatment in 10-month-old PSGL-1^-/-mouse and PSGL-1^+/+mouse with C57BL/6J background.The DOCA administration method is a DOCA sustained-release tablet（50 mg,21 days release）implanted subcutaneously on the back,and the salt administration method is saline feeding（water containing 0.9%Na Cl and 0.2%KCl）.The mouse were divided into six groups:（1）Wide-type mice+SALT（2）Wide-type mice+SALT+DOCA（3）PSGL-1^+/++SALT（4）PSGL-1^+/++SALT+DOCA（5）PSGL-1^-/-+SALT（6）PSGL-1^-/-+SALT+DOCA.After anesthesia with isoflurane,the degree of dilation of the abdominal aorta and the formation of aneurysms in the mice were observed by ultrasound.2.HE staining,Masson trichrome staining,EVG staining and a-SMA staining to detect the pathological changes of the abdominal aorta.3.RT-PCR,Western blot and immunofluorescence staining were used to detect the expression level of PSGL-1 in the aortic tissue of mice with aneurysm.4.RT-PCR method was used to detect the expression level of inflammatory factors in the aortic tissue of mice with aneurysm.5.Flow cytometry to identify leukocyte populations and detect the expression level of PSGL-1 on leukocytes.Peripheral blood mononuclear cell-endothelial cell adhesion rate to determine the number of peripheral blood mononuclear cells adhering to endothelial cells and RT-PCR was used to detect the expression level of adhesion molecules in aortic tissue.6.Immunofluorescence and Western blot were used to detect the activation status of NF-κB signaling pathway in aortic tissue.7.After TNF-αwas injected in vivo,RT-PCR was used to detect the expression level of adhesion molecules in the aortic tissue.Results 1.A mouse model of aneurysm was successfully established using DOCA+SALT.2.The expression level of PSGL-1 in the aortic tissue of mouse with aortic aneurysm increased.3.PSGL-1 knockout reduces the elastic fiber breakage,collagen accumulation and smooth muscle cell degeneration in aneurysm tissue,and reduces the pathological degree of aortic aneurysm.4.PSGL-1 knockout reduces the expression of pro-inflammatory factors（TNF-α,IL-6,IL-1β,CCL-2）and increases the expression of anti-inflammatory factors（IL-10,IL-13）in the aortic tissue.5.PSGL-1 knockout inhibits the activation of NF-κB signaling pathway and reduces the adhesion ability of peripheral blood mononuclear cells and endothelial cells and the expression of adhesion factors.Conclusion The expression level of PSGL-1 was increased in DOCA plus SALT induced mouse aortic aneurysm tissue.PSGL-1 knockout can reduce the adhesion of leukocytes to endothelial cells,decrease the expression of inflammatory factors in the aortic tissue and ameliorate the pathological injury of aneurysms by inhibiting the activation of NF-κB signaling pathway...