Objective: To investigate the possible effects of angiotensinⅡ(AngⅡ) on fatty liver injury and its possible mechanism via the construction of AngⅡ perfusion model. Methods: C57BL/6 mice were randomly divided into three groups: the control group, the AngⅡ group and the AngⅡ with angiotensinⅡ type 1 receptor(AT1R) gene knockout group. Lipid accumulation was examined with haematoxylin-eosin(HE) staining, Oil red O staining, Filipin staining, and a quantitative assay of intracellular cholesterol. The protein expressions of low-density lipoprotein receptor(LDLR), sterol regulatory element-binding protein 2(SREBP-2) and its cleavage activating protein(SCAP) were determined by immunochemical staining and Western blotting. Results: AngⅡ stimulation increased lipid deposition in livers of C57BL/6 mice, which was associated with increased protein expression of LDLR,SCAP, and SREBP-2. However, lipid accumulation in hepatic cells of AT1R gene knockout C57BL/6 mice dropped; moreover, the expression of LDLR pathway related protein significantly dropped. Conclusion: AngⅡ disrupts LDLR feed-back regulation via its receptor AT1R to increase cholesterol uptake and induce intracellular lipid accumulation, contributing to the development of liver injury. |
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