The Role Of CD40 In Atherosclerosis And The Regulatory Effect Of Micro RNA-145

Objective The purpose of this study was to explore the role and mechanism of mi R–145 and CD40 in the process of atherosclerosis(atherosclerosis,AS)and the inflammatory process by establishing inflammatory injury cell model.Methods1.Ten eight week-old male wild-type C57BL/6J mice were fed with normal diet,as the control group.Ten eight week-old apolipoprotein E gene knockout(Apo E-/-)mice were fed with high fat diet,it was the model group whose target was to build the AS model.After feeding for 12 weeks,levels of inflammatory cytokines(IL–1,IL–6,TNF–?)were determined by cardiac puncture,and detection of blood lipid(TC,TG,LDL,HDL)level by automatic biochemical detector.The mice were sacrificed and stained with HE staining and immunohistochemistry.2.Mouse macrophage cell line RAW 264.7 cells cultured in vitro were randomly divided into mi R–145 mimic group(mimic)and its negative control group(NC),mi R–145 inhibitor group(inhibitor)and its negative control group(i NC),silencing CD40 sequence group(si CD40)and its negative control group(si NC).Then transfected mi R–145 mimic,NC,mi R–145 inhibitor,i NC,si CD40,si NC(5ul/ml)into the cells.Stimulate 48 h with oxidized low density lipoprotein(ox–LDL)(3.20mg/ml)to establish immune inflammatory damage cell model.Quantitative real-time polymerase chain reaction(RT–q PCR)and western blot were used to detect the levels of the expression of CD40 m RNA and protein;enzyme linked immunosorbent assay(ELISA)were used to detect the levels of inflammatory factors(IL–1,IL–6,TNF–?)in cell supernatant.Results1.AS model can be successfully established by feeding high-fat diet to 8 week-old male mice.Apo E-/-mouse has more visible plaque formation in the aorta,more significantly increased of the expression level of CD40 protein,more obvious increased of the levels of inflammatory factors(IL–1,IL–6,TNF–?)in blood(P<0.05),more significantly increased of TC?LDL levels(P<0.05),evidently decreased of HDL levels(P<0.05),and there was no significant difference in TG level(P>0.05).2.Compared with NC group,the levels of CD40 m RNA,CD40 protein and inflammatory factors(IL–1,IL–6,TNF–?)in mimic group were all significantly decreased(P<0.05).Compared with i NC group,the levels of CD40 m RNA,CD40 protein and inflammatory factors(IL–1,IL–6,TNF–?)in inhibitor group were all evidently increased(P<0.05).Compared with si NC group,the levels of CD40 m RNA,CD40 protein and inflammatory factors(IL–1,IL–6,TNF–?)in si NC group were all obviously decreased(P<0.05).Conclusions Mi R–145 regulated the immune inflammatory process of atherosclerosis through the target gene CD40,inhibit the activation of CD40/CD40 L signaling pathway and inhibit inflammatory response,so as to inhibit the occurrence and development of AS.