Abstract:Aim To investigate the effect of OX40-OX40L interaction on the expression of nuclear factor of activated T cells c1 (NFATc1) and formation of the atherosclerotic plaques. Methods Atherosclerotic plaque model was randomly divided into the following groups:control group (n=11),OX40 activated group (n=11) and OX40 activated+PLKO.1-shNFATc1 group (n=11). Atherosclerotic plaque model was produced by perivascular carotid collar placement in ApoE－/－ mice. Masson staining was used to detect the composition of the plaque. Immunohistochemistry was used to observe the distribution of NFATc1 and CD68 in plaques. Mouse brain endothelial cells were divided into three groups:control group, OX40 activated group and OX40 inhibited group. The mRNA and protein level of NFATc1 was detected by real-time quantitative PCR (qRT-PCR) and Western blot respectively. Results In vitro, the expression level of NFATc1 was significantly increased in OX40 activated group, and were decreased in OX40 inhibited group(P<0.05). In vivo, the expression level of NFATc1 was significantly increased in OX40 activated group, and were decreased after the gene of NFATc1 being silenced(P<0.05). Masson staining revealed that the area of the plaque and fibrin proliferation was higher than the control group, while were decreased in OX40 activated+PLKO.1-shNFATc1 group. In vivo,compared with the control group, the distribution of NFATc1 and CD68 in the plaque were increased after the addition of agonist-OX40, which can be inhibited by silencing NFATc1. Conclusion OX40-OX40L interaction may regulate the expression of NFATc1 and promote the formation of the atherosclerotic plaque.

Abstract:Aim To investigate effect of OX40-OX40L signal on the expression of cyclophilin A （CyPA） in atherosclerotic plaque of apolipoprotein E gene knockout （ApoE－/－） mice. Methods Atherosclerotic plaque model was produced by perivascular carotid collar placement in ApoE－/－ mice. 48 male ApoE－/－ mice were anesthetized by intraperitoneal injection of ketamine. Subsequently, the right common carotid artery was separated, and Silicone Collar was placed on the right common carotid artery. ApoE-/- mice were randomly allocated to inhibition group （intraperitoneal injection of anti-OX40L 200 μg, once a week, 6 weeks）, stimulation group （intraperitoneal injection of anti-OX40 200 μg, once a week, 6 weeks） and control group （intraperitoneal injection of IgG2b 200 μg, once a week, 6 weeks）, mice were sacrificed after high fat diet and intraperitoneal injection of antibodies was received for 6 weeks. The expression of CyPA protein and mRNA levels in atherosclerotic plaque were detected by immunohistochemisty, Western blot, qRT-PCR, respectively. Results Dealing with perivascular carotid collar placement and high fat diet in ApoE－/－ mice after 6 weeks, plaque formation, part of intima and media thickening and elastic lamina deformation were detected in control. Compared with control group, the carotid sections of plaque area of stimulation group were significantly increased, while those in inhibition group were significantly decreased, the expressions of CyPA protein and mRNA were significantly increased in atherosclerotic plaque （P<0.05）. However, after intraperitoneal injection of anti-OX40L to inhibit OX40-OX40L ligand, the expressions of CyPA protein and mRNA were significantly decreased in atherosclerotic plaque （P<0.05）. Conclusion The expression of CyPA in ApoE－/－ mice is modulated by the OX40-OX40L signal.