Abstract:Aim To investigate the effect of simvastatin on reactive oxygen species(ROS) expression in stretch stress(SS) induced macrophage cells. Methods RAW264.7 macrophage cells were cultured in vitro, treated with SS, or pretreated with simvastatin for 60 min and then stimulated with SS, the expression of ROS was detected by Hoechst33342 and H2DCFDA fluorescent probe, the fluorescence intensity of ROS was detected and the positive ratio of ROS was analysed by SPSS statistical software. The expression of NADPH oxidase 1(NOX1) was evaluated by Western blot.Results SS increased the expression of ROS in a time dependent manner, and the expression of ROS reached the most significant at 60 min(P<0.05). Simvastatin could inhibit the effect induced by SS in a concentration dependent manner, the inhibition effect of simvastatin was the most significant in 0.3 μmol/L(P<0.05). The expression of NOX1 was significantly inhibited by simvastatin after SS. Conclusion Simvastatin repressed ROS expression of RAW264.7 macrophage cells induced by SS through inhibiting the expression of NOX1.

Abstract:Aim Macrophage apoptosis plays an important role in development of atherosclerotic plaques, necrotic lesions, plaque instability and acute vascular events, so the study of the regulation of Daxx macrophage apoptosis is favorable to reveal new drug targets, providing a theoretical basis for the occurrence of atherosclerosis. Methods The eukaryotic vector of Daxx and pCDNA3.1 were constructed to be stably transfected into RAW264.7 cells, the mRNA and protein expressions of Daxx were used by RT- PCR and Western blot respectively. The intracellular lipid droplets and lipid levels was assayed by enzyme fluorescent analysis. The growth inhibition and apoptotic effect of RAW264.7 cells induced by Chol∶MβCD were analyzed by MTT and flow cytometric analysis. The protein expressions of caspase3 was assayed by western blotting. Results RT-PCR and Western blot analysis showed that the expression of Daxx was significantly increased in gene-transfected RAW264.7 cells. Chol∶MβCD induced cholesterol accumulation and apoptosis in RAW264.7 cells was increased by Daxx. Caspase3 protein levels were significantly elevated in Daxx transfected cells. Conclusion Daxx overexpression could increase Chol∶MβCD induced apoptosis in macrophages.

Abstract:Aim To investigate the effects of baicalin on the expression of toll-like receptor 4(TLR4),inhibitor of κB(I-κB),and the production of tumor necrosis factor-α(TNF-α) in macrophage cells RAW264.7 induced by lipopolysaccharide(LPS).Methods RAW264.7 cells were cultured in vitro,and treated with different concentration of baicalin in the presence or absence of LPS.The mRNA and protein expression of TLR4 were determined by reverse transcription PCR and Western Blot,respectively.The expression of I-κB was detected by Western Blot.The concentrations of TNF-α in the supernatant was determined by enzyme linked immunosorbnent assay.Results LPS significantly up-regulated the expression of TLR4 and production of TNF-α in macrophage cells,and markedly inhibited the expression of I-κB.Pretreated with baicalin down-regulated LPS-induced TLR4 expression in both mRNA and protein levels,as well reduced the secretion of TNF-α.Baicalin significantly inhibited the degradation of I-κB.Conclusion Baicalin might effectively down-regulate TNF-α production in LPS-induced macrophage cells through inhibiting the expression of TLR4 and degradation of I-κB.The antiinflammation effects may be associated with the amelioration of atherosclerosis damage by baicalin.

Abstract:Aim To investigate the effects of noradrenalin on the expressions of transforming growth factor(TGF-)β1 in human THP-1 macrophage cells.Methods THP-1 macrophage cells were incubated with different concentrations of noradrenalin(10 pmol/L ～10 μmol/L)for 24 hour.Then the mRNA levels of TGF-?1 were determined by reverse transcription polymerase chain reaction(RT-PCR).Levels of TGF-β1 in the supernatants of cells were determined by enzyme-linked immunosorbent assay(ELISA).Results THP-1 macrophage cells which treated with 100 nmol/L,1 μmol/L and 10 μmol/L noradrenalin,the mRNA levels of TGF-β1 decreased 9.3%(p<0.05),39.5%(p<0.01)and 47.8%(p<0.01)respectively.THP-1 macrophage cells which treated with 1 μmol/L and 10 μmol/L noradrenalin,the protein levels of TGF-β1 decreased 24.7%(p<0.01)and 32.8%(p<0.01)respectively.Conclusion Stress induced increase of noradrenalin concentrations cause TGF-β1 expression decreased in human THP-1 macrophage cells.