ABSTRACT
Objective To investigate the effect of miRNA-145 (miR-145) on immuno-inflammatory reaction of foam cells by targeting CD40. Methods Mouse macrophage cell line RAW 264.7 cells cultured in vitro were randomly divided into model group (non-transfected), miR-145 mimics group (transfected miR-145 mimics), miR-145 inhibitor group (transfected miR-145 inhibitor) and silencing CD40 sequence group (transfected siCD40). Then oxidized low density lipoprotein (ox-LDL) was used to stimulate for 24 h to establish immune inflammatory damage cell model. Quantitative real-time polymerase chain reaction (RT-qPCR) and Western blot assay were used to detect the levels of CD 40 mRNA and protein of each group. ELISA was used to detect the levels of inflammatory factors interleukin (IL)-1, IL-6 and tumor necrosis factor (TNF) -α in cell supernatant. Results Compared with model group, the levels of CD40 mRNA, CD40 protein and IL-1, IL-6, TNF-αwere all significantly decreased in miR-145 mimics group (P<0.01). After transfected with miR-145 inhibitor, the above indexes were all significantly increased than those of model group and miR-145 mimics group (P<0.01). After transfected with CD40 siRNA, the levels of CD40 mRNA, CD40 protein and IL-1, IL-6, TNF-αwere all obviously decreased compared with those of miR-145 inhibitor group (P<0.01). Conclusion MiR-145 can regulate the immune inflammatory process of foam cells through the target gene CD40, inhibit the activation of CD40/CD40L signaling pathway and inhibit inflammatory response.
ABSTRACT
Objective To investigate the effects of microRNA-155 (miR-155) on immuno-inflammatory reaction of foam cells by targeting MyD88 and the possible mechanism. Methods RAW264.7 macrophages were cultured in vitro and transfected with miR-155 mimics, miR-155 inhibitor, MyD88 siRNA and their negative control respectively, then ox-LDL stimulation was given to build foam cell model. The expression of MyD88 in foam cells was detected by RT-qPCR and Western blot assay. Moreover, the expression levels of interleukin (IL)-10, TGF-β1 and MCP-1 in supernatant were determined by ELISA. Results After being transfected with miR-155 mimics, the mRNA level of MyD88 remained unchanged compared with that of control group (P>0.05). The protein level of MyD88 decreased significantly (P<0.05), and the expression levels of IL-10, TGF-β1 and MCP-1 in supernatant also decreased significantly (P<0.05). After being transfected with miR-155 inhibitor, the mRNA level of MyD88 remained unchanged compared with that of control group (P>0.05). The expression levels of MyD88 protein and inflammatory cytokines increased significantly (P<0.05). After being transfected with MyD88 siRNA, the expression levels of MyD88 mRNA and protein decreased significantly, and the expression levels of inflammatory cytokines also decreased significantly (P<0.05). Conclusion miR-155 can negatively regulate inflammation by targeting MyD88 through the inhibition of translation.
ABSTRACT
Objective To investigate the effects of microRNA-155 (miR-155) on immuno-inflammatory reaction of foam cells by targeting MyD88 and the possible mechanism. Methods RAW264.7 macrophages were cultured in vitro and transfected with miR-155 mimics, miR-155 inhibitor, MyD88 siRNA and their negative control respectively, then ox-LDL stimulation was given to build foam cell model. The expression of MyD88 in foam cells was detected by RT-qPCR and Western blot assay. Moreover, the expression levels of interleukin (IL)-10, TGF-β1 and MCP-1 in supernatant were determined by ELISA. Results After being transfected with miR-155 mimics, the mRNA level of MyD88 remained unchanged compared with that of control group (P>0.05). The protein level of MyD88 decreased significantly (P<0.05), and the expression levels of IL-10, TGF-β1 and MCP-1 in supernatant also decreased significantly (P<0.05). After being transfected with miR-155 inhibitor, the mRNA level of MyD88 remained unchanged compared with that of control group (P>0.05). The expression levels of MyD88 protein and inflammatory cytokines increased significantly (P<0.05). After being transfected with MyD88 siRNA, the expression levels of MyD88 mRNA and protein decreased significantly, and the expression levels of inflammatory cytokines also decreased significantly (P<0.05). Conclusion miR-155 can negatively regulate inflammation by targeting MyD88 through the inhibition of translation.