Objective To explore the role and the possible molecular mechanisms of natural anti-oxLDL IgM monoclonal antibody played and involved in pathogenesis of atherosclerosis. Methods Natural anti-oxLDL IgM monoclonal antibody 3A6 was generated by using standard hybridoma production techniques. Influence of 3A6 on formation of foam cells was observed by Oil Red O staining and affinity of Na125I-conjugated oxLDL on the naive and LPS-activated macrophages. After LPS stimulation on macrophages, anti-TLR4 neutralizing mAb, p38MAPK specific inhibitor SB203580, NF-kB specific inhibitor PDTC or RNAi targeting Fcα/μ receptor (Fcamr) were applied, respectively. Results Natural anti-oxLDL IgM monoclonal antibody 3 A6 were found specifically inhibit the binding of CuoxLDL to naive macrophages but not the binding of CuoxLDL to LPS-activated macrophages. It also promoted the formation of CuoxLDL-mediated foam macrophages. 3A6 F(ab')2 or pre-incubation with un-related IgM inhibited the binding of 3A6/CuoxLDL complex to LPS-activated macrophages. LPS up-regulated the expression of Fcamr in macrophages in a dose- and time-dependent manner, which was attenuated by treatment with anti-TLR4. LPS induced the phosphorylation of p38MAPK and translocation of NF-kB p65, contributing to the up-regulated expression of Fcα/μ receptor in macrophages. Conclusions Natural anti-oxLDL IgM monoclonal antibody 3A6 specifically inhibited the binding of CuoxLDL to naive macrophages in vitro. However, LPS, through the Toll-like receptor (TLR)4 receptor, activated the p38MAPK and NF-kB pathways and up-regulated the expression of Fcα/μ receptor in macrophages, which promoted the binding of 3A6/CuoxLDL complex to macrophages through binding with Fc fragments and the formation of foam macrophages. Therefore, our findings provide a new explanation why bacterial infection deteriorates the pathogenesis of atherosclerosis.

AIM: To examine the effects of L-carnitine on apoptosis and oxidant injury in cultured neonatal rat cardiomyocytes induced by hypoxia/reoxygenation and its possible mechanism. METHODS: The cultured cardiomyocytes were divided into three groups, control, A/R group (anoxia for 120 min, reoxygenation for 240 min) and L-carnitine treatment group, in which cells were exposed to 20 mg/L, 50 mg/L, 100 mg/L, 200 mg/L L-carnitine respectively at 2 h before anoxia. The superoxide dismutase (SOD), succinate dehydrogenase (SDH) activities and malondialdehyde (MDA) content were examined, and the apoptosis was determined by flow of cytometry (FCM). In addition, the ultrastructure was observed by transmission electron microscopy. RESULTS: In A/R group, SOD and SDH activities were lower, the apoptosis rate and MDA content were higher than those in control group (P

AIM: To examine the effects of L-carnitine on apoptosis in cultured neonatal rat cardiomyocytes induced by hypoxia/reoxygenat ion and its possible mechanism. METHODS: A cell culture model of neonatal rat cardiacmyocytes wa s used. The cultured cardiomyocytes were classified into three groups: control g roup, I/R group (anoxia for 120 min, reoxygenation for 240 min) and L-carnitine group (L-carnitine, which was classified into four different concentrations, was added to the cells 2 h before anoxia). The activities of superoxide dismutase ( S OD), the content of malondialdehyde (MDA) and the apoptosis were determined by f low cytometry (FCM). RESULTS: In I/R group SOD activities were lower, and the apoptos is rate and MDA were higher than those in control group and they were statistica lly significant (P

Objectives:We aimed to compare the impact of dissection and re-entry(DR)recanalizing pattern with non-DR on the in-hospital results and prognostic outcomes of patients treated successfully by percutaneous coronary intervention(PCI)of chronic total occlusion(CTO)and examine the benefit of DR in CTO PCI. Methods:A total of 815 consecutive patients with CTO meeting the inclusion criteria in the Department of Cardiology of the First Affiliated Hospital of PLA Air Force Military Medical University from January 2018 to December 2020 were enrolled and divided into DR group(n=239)and non-DR group(n=576)according to whether DR recanalizing pattern was used in the procedure.The clinical characteristics,coronary angiographic characteristics,procedure results,and complications were collected,and the prognostic outcomes within one year after the procedure were observed.Propensity score matching by the clinical and coronary angiographic characteristics was performed and results were compared with 208 matched patients in each group.The endpoints were the major adverse cardiovascular events(MACE)consisting of all-cause death and myocardial infarction,clinically driven target vessel revascularization(TVR)one year after the procedure,and in-hospital outcomes. Results:The mean age of all patients was(60.9±10.9)years old,and 87.4%were male.As compared with the non-DR group,the proportion of blunt cap,ambiguous,calcification,angle＞45°,and diseased landing zone,as well as mean J-CTO score was higher in the DR group(all P＜0.05).The mean stent length and median procedure time were longer in the DR group,median guidewires and consumed contrast volume was also higher in the DR group(all P＜0.001).Incidence of in-hospital death,myocardial infarction,perforation,side branch loss,bleeding of BARC 3rd grade and above,and contrast-related impairment of renal function were similar between the two groups(all P＞0.05).However,peripheral vascular complications occurred more frequently in the DR group(P=0.007).One year after the procedure,the incidence of MACE(2.9%vs.2.4%,log-rank P=0.750)and clinically driven TVR(5.8%vs.3.9%,log-rank P=0.365)as well as all-cause death(2.9%vs.1.0%,log-rank P=0.154)and myocardial infarction(0.5%vs.1.9%,log-rank P=0.184)were similar between the two matched groups.Multivariate Cox regression analysis showed no significant association between DR and MACE(HR=1.129,95%CI:0.427-2.979,P=0.807)and TVR(HR=0.606,95%CI:0.213-1.722,P=0.347).LVEF≤40%(HR=2.775,95%CI:1.137-6.774,P=0.025)and elevated residual SYNTAX score(HR=1.089,95%CI:1.032-1.150,P=0.002)were risk factors for MACE,and diseased landing zone(HR=2.144,95%CI:1.019-4.513,P=0.045),rescued ADR(HR=3.479,95%CI:1.109-10.919,P=0.033),and prolonged procedure time(HR=1.007,95%CI:1.002-1.013,P=0.007)were risk factors for TVR. Conclusions:CTO lesion recanalized with PCI utilizing DR operation pattern was associated with more complex characteristics,more devices and time consumed,and longer stent length,while no significant association was observed between DR operation pattern and MACE and TVR one year after the procedure,as well as in-hospital complication..