ABSTRACT
OBJECTIVE: To investigate the protective effects and mechanism of extracts of Rehmanniae against atherosclerosis by “IL-34”-Rho/Rock pathway in ApoE-/-mice. METHODS: ①Animal experiment 40 ApoE-/- mice were randomly divided into CTL group, Model group, Reh-L group (5 μg·g-1) and Ren-H group (10 μg·g-1), which were induced by low-density lipoprotein (LDL) for AS models. The serum levels of interleukin-34 (IL-34), LDL, mouse monocyte chemotactic protein 1 (MCP-1), mouse macrophage inflammatory protein 2(MIP-2) and endothelin-1 (ET-1) were detected by ELISA. AS index (AI) was calculated according to the serum lipids levels. ②Macrophage experiment RAW264.7 macrophages were cultured in vitro and divided into con group, ox-LDL group, IL-34 group and Reh group. IL-34-indeced foam cells formation by oil red O staining. The cholesterol ester levels and cholesterol efflux of RAW264.7 macrophages were detected. The immunofluorescence, qRT-PCR, Western blot analysis were used to detect RhoA and Rock1 expression. RESULTS: ①Animal experiment the serum levels of TC, TG, LDL-C, ET-1, IL-34, MCP-1, MIP-2 and AI, atherosclerotic lesion areas of the thoracic aorta of mice in Reh-H group were lower than Model group and Reh-L group, but with higher HDL-C level (P<0.05). Compared with the CTL group, the RhoA and Rock1 levels of aorta tissues in Model group were significantly increased by qRT-PCR and Western blot (P<0.05). But the RhoA and Rock1 levels of aorta tissues in Reh-H group were lower than Model group or Reh-L group (P<0.05). ②Macrophage experiment the cholesterol ester level and cholesterol efflux, RhoA and Rock1 expressions of RAW264.7 macrophages induced by ox-LDL and IL-34 were more than con group and ox-LDL group (P<0.05). Compared with IL-34 group, the cholesterol ester level and cholesterol efflux, RhoA and Rock1 expressions of RAW264.7 macrophages in Reh group were significantly decreased (P<0.05). CONCLUSION: The extracts of Rehmanniae can protectagainst atherosclerosis in ApoE-/- AS mice models induced by LDL through inhibiting “IL-34”-Rho/Rock pathway.