Author + information
To investigate the mechanism of CML/CD36 accelerating atherosclerotic progression via inhibiting foam cell migration.
In vivo investigation, male apoE−/−mice were rendered diabetic at six weeks of age by intraperitoneal injections of streptozotocin (STZ, 40 mg/kg) for five days in succession, the mice with blood glucose levels of ≥300 mg/dL were considered diabetic after the STZ administration for two weeks. Then the mice were divided into four groups: control group (normal diet, n=8), model group (high fat diet, n=8), CML group (high fat diet + the injection of CML 10 mg/kg/day, n=8), and anti-CD36 group (high fat diet + the injection of CML 10 mg/kg/day+ the injection of anti-CD36 antibody 100 μg/week, n=8). The mice were euthanized after four months and performed for serology analysis, morphological analysis, and molecular biology detection. In vitro investigation, foam cell model was formed by RAW264.7 cells loaded with 40μg/mL ox-LDL, the following studies were investigated based on the foam cell: the effect of CML on the foam cell CD36 expression and actin polymerization, the effect of CML on the foam cell migration, the role of CD36 in the foam cell migration induced by CML, and the related pathway of CML/CD36 in foam cell migration were investigated. The related analyses such as Oil red O staining, the enzyme method of cellular cholesterol contents,transwell migration assay and wound-healing assay, immunoprecipitation, immunofluorescence staining, DCF method of ROS generation, western blot assay and quantitative real time PCR were performed.
In vivo investigation, CML can increase the atherosclerotic plaque areas, lipid accumulation and total cholesterol contents in atherosclerotic plaques of apoE−/− mice, while the areas of vascular plaque, lipid accumulation and total cholesterol contents in anti-CD36 group were significantly reduced. While in para-aorta lymph node, lipid accumulation and cholesterol contents increased in anti-CD36 group when compared with CML group. The CD68 protein expression of aortic plaque in anti-CD36 group was obviously lower than that of CML group, but the CD68 protein expression of para-aorta lymph nodes in anti-CD36 group was significantly higher than that of CML group. In vitro investigation, CML/CD36 inhibited the migration of RAW264.7-derived foam cells, and it was related with free cholesterol generation, ROS production, the activation of phosphorylated focal adhesion kinase (FAK), Arp2/3 and actin polymerization.
CML/CD36 inhibited foam cells of plague migrating to para-aorta lymph nodes, accelerating atherosclerotic progression in apoE−/− mice, the corresponding mechanism may be via free cholesterol, ROS generation, p-FAK, Arp2/3, F-actin.